ALBERT

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 467〈/p〉 〈p〉Author(s): Hyunkyung Lee, Jihun Lim, Min Zhan, Seungkwan Hong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Preoxidation is gaining spotlight in the mitigation of ultrafiltration (UF) membrane fouling caused by algal organic matter (AOM). Although it is known to be beneficial in freshwater, its applicability in seawater treatment has barely been explored. This study first evaluated the effect of UV/permonosulfate (PMS) oxidation for UF process against marine harmful algal blooms (HAB). The transition of AOM released from 〈em〉Pseudo Nitzchia〈/em〉 was investigated which produces a neurotoxin, domoic acid (DA). Specifically, UV light emitting diodes (LED) were employed as UV source. The results indicated UV-LED/PMS treatment effectively reduces the fouling potential of AOM. However, the participation of abundant chloride ions generated free chlorine and disinfection byproducts, thus, PMS addition below 0.5 mM was suggested for seawater applications. With respect to PMS 0.5 mM, TOC and cake layer resistance were reduced by 10% and 85%, respectively, and this was followed by significant improvements in water permeability, flux reversibility and permeate quality of UF process. Furthermore, PMS exhibited significant reactivity for decomposing DA achieving rapid disappearance of 1 ppm of DA within a minute. The aforementioned results encourage the use of PMS as a bulk oxidant in seawater treatment to simultaneously mitigate membrane fouling and improve permeate quality.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418325608-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 470〈/p〉 〈p〉Author(s): Francisco J. Alcalá〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The chloride-to-bromide molar ratio (R ≡ Cl/Br) is widely used in tracing groundwater salinity. Less experience exists on how some industrial processes such as the reverse osmosis (RO) water treatment modify the R value of desalinated water (P) and reject brine (T), and even less on how distinctive for hydrogeological applications the R changes are. This paper assesses the Cl/Br ratio usefulness to identify the effect of P and T on groundwater systems. First, the experimental R changes produced in P and T during standard RO operations and treatments of raw (I) seawater, brackish groundwater, and tertiary-treated domestic wastewater in nine RO plants (three in Gran Canaria Island and six in south-eastern continental Spain) were determined by means of the X〈sub〉P〈/sub〉 = R〈sub〉P〈/sub〉/R〈sub〉I〈/sub〉 (R change in P) and X〈sub〉T〈/sub〉 = R〈sub〉T〈/sub〉/R〈sub〉I〈/sub〉 (R change in T) ratios. X〈sub〉P〈/sub〉 and X〈sub〉T〈/sub〉 were respectively 0.90 and 1.07 for treatment 1 (weak pre-acidification) in one RO plant, 0.82 ± 0.09 and 0.94 ± 0.05 for treatment 2 (weak pre-acidification and weak pre-chlorination) in five RO plants, 0.63 and 0.97 for treatment 3 (moderate pre-acidification and strong pre-chlorination) in one RO plant, and 3.21 ± 2.02 and 1.00 ± 0.00 for treatment 4 (post-chlorination) in two RO plants. P was for irrigation (treatments 1 to 3) and for domestic use (treatment 4). Latter, the experimental X〈sub〉P〈/sub〉 and X〈sub〉T〈/sub〉 ratios were input data for six theoretical mixing scenarios aimed at showing how groundwater R changes in response to progressive contributions of P and T produced from different I water. The Cl/Br ratio enables to identify the effect of P from treatments 3 and 4, is scarcely effective for treatments 1 and 2, and is especially useful when P produced from seawater is used in other aquifer having different R. The Cl/Br ratio did not clearly identify T from any treatment.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419306988-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Jin Tang, Chuyi Wang, Wenjing Xie, Yahao Xia, Tao Yu, Zhili Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Tubular still is one of the most promising desalination devices. This paper presents hydrophilic modification of the outer surface of the seawater trough in a tubular still, so that the hydrophilically modified outer surface can serve as an evaporation surface when it is wetted with the overflowing seawater from the trough. To experimentally verify and examine the effect of hydrophilic surface modification, a small tubular still was constructed with a seawater trough of 63 mm in diameter and 1.9 m in length. The experimental results show that at the operating temperature of 80 °C, the hydrophilically modified surface can increase the yield rate by 24.9%. Under the condition with a constant input power of 100 W, the hydrophilically modified surface can increase the gained output ratio (GOR) of the tubular still by 44.4%. In addition, a heat and mass transfer model of tubular still is also presented for a theoretical performance prediction of the effect of hydrophilic surface modification. A comparison exhibits the maximum deviation of 18.7% between the theoretical and experimental results.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 470〈/p〉 〈p〉Author(s): Suhaib M. Alawad, Atia E. Khalifa〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A detailed theoretical model of water gap membrane distillation process is presented for water desalination. The model predicts the permeate flux through the analysis of the coupled heat and mass transfer and steady-state energy balance through membrane and module layers. Natural convection inside the water gap is studied. Effects of membrane support plate and its geometry are included to account for different areas of heat and mass transfers. Model validation shows that considering the natural convection in the water gap is critical, except for gap widths less than 1 mm, where pure conduction prevails inside the gap. A modified correlation of the gap Nusselt number is adopted and validated. The new correlation provides very good match to experimental results for the water gap module under study. System performance indicators like evaporative efficiency, polarization coefficients, and gain output ratio (GOR) are studied. The efficiency reached a maximum of 93% at high feed temperature of 90 °C and high feed flow rate of 6 L/min. GOR reached a maximum value of about 1.3 at 90 °C and low feed rate of 1.5 L/min. The width of water gap has marginal effects on EE and GOR.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 470〈/p〉 〈p〉Author(s): Yoshiki Okamoto, John H. Lienhard〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Reverse osmosis (RO) technology has progressed steadily over the last few decades. Those gains were achieved through improvements in both RO membrane element performance and energy recovery technologies. However, some recent literature indicates that RO membrane water permeability is approaching performance limits imposed by transport processes and thermodynamic constraints. This paper reviews how RO membrane element performance affects the cost of RO processes, especially the specific energy consumption. RO membrane performance encompasses water permeability, salt permeability, and other some characteristics of the RO element. This paper considers not only conventional RO processes, but also the recently proposed closed-circuit RO and batch RO processes. Even if the membrane water permeability increases, little additional effect is found when the membrane water permeability exceeds around 3 LMH/bar for seawater RO and 8 LMH/bar for brackish water RO in conventional single-stage RO. Increasing membrane water permeability has the potential to decrease membrane surface area and associated costs. A major limitation of most existing literature is that performance is evaluation on in terms of the initial operating conditions. Chronological changes, such as result from fouling, must also be considered to accurately validate how membrane element performance affects RO cost.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 470〈/p〉 〈p〉Author(s): Xiaoru Wen, Meiqi Zhao, Dongxu Zhang, Xiangdong Ma, Zhiqiang Lin, Meidan Ye〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Capacitive deionization (CDI) based on the principle of electrochemical double layers has emerged as a prospective water treatment technology to challenge the water scarcity. Herein, a novel integrated CDI electrode comprised of large-scale and vertically aligned Co(OH)〈sub〉2〈/sub〉 nanosheets on the GP matrix (Co(OH)〈sub〉2〈/sub〉@GP) has been prepared successfully via a facile hydrothermal strategy for the first time. The texture analyses such as TEM, SEM, XPS, XRD and N〈sub〉2〈/sub〉 adsorption indicated that well-grown and interconnected Co(OH)〈sub〉2〈/sub〉 nanosheets on the GP matrix ensured the electrode a high specific surface area (207.62 m〈sup〉2〈/sup〉/g) and superior open pore network. The electrochemical performance investigated by the CV, EIS and GC techniques revealed that the Co(OH)〈sub〉2〈/sub〉@GP electrode combing the merits of Co(OH)〈sub〉2〈/sub〉 nanomaterial and GP efficiently obtained the amazing specific capacitance of 411.02 F/g, good electric conductivity and favourable cyclability. Moreover, the CDI behaviour of Co(OH)〈sub〉2〈/sub〉@GP electrode evaluated by the batch mode experiments in the 300 mg/L of NaCl solution demonstrated an ultrahigh salt removal capacity of 48.21 mg/g and excellent regeneration ability. The highly simplified electrode processing, free binder and outstanding CDI performance render the Co(OH)〈sub〉2〈/sub〉@GP electrode a promising candidate in the highly efficient CDI application.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419312391-ga1.jpg" width="345" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 470〈/p〉 〈p〉Author(s): Jaichander Swaminathan, Emily W. Tow, Richard L. Stover, John H. Lienhard〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Batch operation of reverse osmosis (RO) has been proposed as a method to reduce seawater RO (SWRO) energy consumption and fouling propensity. In this paper, we use a transient numerical model of the RO process to investigate the impact of several practical loss mechanisms on the overall energetic performance of batch SWRO compared to a conventional continuous system. A critical variable that controls the energetic advantage of batch RO is the reset time between cycles. A large reset time necessitates higher operating flux and therefore results in increased energy consumption. On the other hand, ensuring a low cycle reset time requires higher energy for the refilling process. A batch SWRO design with an atmospheric pressure feed tank and pressure exchangers for energy recovery does not show promise for energy savings. Batch SWRO must be designed with a large number of short pressure vessels (with fewer membranes each) and lower energy recovery losses (e.g., by using pressurized feed storage) in order to reduce energy consumption by up to 8〈em〉%〈/em〉. These modifications are more complex and hence capital expenses would determine the overall feasibility of such designs to improve seawater desalination.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Kwanghyun Kim, Sunyoung Yu, Se-Young Kang, Seung-Tak Ryu, Ji-Hyun Jang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The evaporation sites of a solar desalination device were expanded from conventional 2D to a new type of 3D by leaving the side area of the porous water transporter exposed to the air. The 3D solar desalination device permits not only photothermal distillation by the photoabsorbers at the top under sunlight illumination, but also additional non-photothermal evaporation on the side of the water transporter that works even at night by exploiting environmental heat. For the first time, we developed a unique configuration of water transport exposed to the environment with a great contribution to an active site increase and confirmed the significant impact of the active site increase on the solar desalination performance by systematic and strong pieces of evidence. Due to the effective utilization of enormous evaporation sites on the top and side surfaces in the 3D configuration, the device exhibited a significant steam generation rate of ~0.74 g/h under 1 sun illumination, which is ~1.5 times higher than the maximum value achieved with photothermal evaporation only. Our study suggests an innovative change which incorporates additional non-photothermal evaporation in the solar desalination device can be a straightforward and efficient way to address clean water deficiencies worldwide in the future.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 12 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination〈/p〉 〈p〉Author(s): Jongmoon Choi, Pema Dorji, Ho Kyong Shon, Seungkwan Hong〈/p〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Yuquan Li, Zibiao Ding, Junfeng Li, Jiabao Li, Ting Lu, Likun Pan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Hybrid capacitive deionization (HCDI), normally consisting of a faradaic electrode, typically inorganic intercalation compounds, and an electric double layer carbon electrode, is an efficient and high performance alternative to the conventional capacitive deionization. In this work, for the first time we introduced a redox-active polyimide, poly[N,N′-(ethane-1,2-diyl)-1,4,5,8-naphthalenetetracarboxiimide] (PNDIE) as a novel electrode material of HCDI. In 1 M NaCl solution, PNDIE exhibits a capacitor-like fast rate performance and a high specific capacity of 89.9 mAh g〈sup〉−〈/sup〉〈sup〉1〈/sup〉 at 0.2 A g〈sup〉−〈/sup〉〈sup〉1〈/sup〉 (corresponding to 359.6 F g〈sup〉−〈/sup〉〈sup〉1〈/sup〉 at 0.9 V voltage), which outperforms those of most reported carbonaceous and faradaic electrode materials for desalination application. When used as cathode of HCDI with activated carbon anode, PNDIE shows a high sodium uptake capacity of 54.2 mg g〈sup〉−〈/sup〉〈sup〉1〈/sup〉 and excellent electrochemical stability under open-air environment. Moreover, the parasitic side reaction of PNDIE cathode with dissolved oxygen in HCDI was detailedly studied, which should also cause some capacity loss in HCDI with faradaic electrode but was seldom reported in the previous work. The strategy in this work should provide a new insight in exploring novel redox-active and stable HCDI polymer electrode instead of conventional inorganic intercalation compounds for highly efficient and stable desalination application.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419308422-ga1.jpg" width="432" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Yu-Hsuan Chiao, Shu-Ting Chen, Tanmoy Patra, Chen-Hua Hsu, Arijit Sengupta, Wei-Song Hung, Shu-Hsien Huang, Xianghong Qian, Ranil Wickramasinghe, Yung Chang, Kueir-Rarn Lee, Juin-Yih Lai〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, superfast surface modification of forward osmosis (FO) membranes was accomplished using zwitterionic species with improved antibacterial and antifouling properties. Asymmetric thin film composite (TFC) FO membranes were fabricated using superfast second interfacial polymerization (SIP). The active sides of the TFC membranes were modified with zwitterionic polyamide moieties. Subsequently, the effects of surface modification on the surface properties, morphologies, and surface charges of the TFC membranes were investigated. The TFC membranes exhibited drastically improved performance in FO processes with model and real produced water samples. The zwitterion-augmentation significantly enhanced surface hydrophilicity and shielded negative surface charge distribution on the membrane surface. Furthermore, static protein absorption and dynamic protein fouling tests with model foulant sodium alginate (SA) revealed that the antifouling characteristics of the asymmetric TFC membranes had improved remarkably. SIP with zwitterion incorporation reduced protein absorption and promoted consistent flux during permeation with the model foulant solution. The antimicrobial characteristic of these FO membranes is also demonstrated with bacterial attachment on membrane surface using 〈em〉Escherichiacoli〈/em〉. Overall, the zwitterion-augmented surface modification of these FO membranes resulted in enhanced permeability and reduction in surface structure parameter leading to improved antifouling properties with respect to organic proteins and gram-positive bacteria.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419310070-ga1.jpg" width="468" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Zhaohuan Mai, Shuanglin Gui, Jiaqi Fu, Cheng Jiang, Emily Ortega, Yan Zhao, Wenqing Tu, William Mickols, Bart Van der Bruggen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A framework of reformulation of the classic solution-diffusion model is presented by combining the film theory and electrolyte theory to include the concentration polarization and thermodynamic non-idealities in mass transport of NaCl/NH〈sub〉4〈/sub〉Cl solutions during reverse osmosis in a large range of feed concentrations. In this activity-derived model, concentration polarization was evaluated using the film theory to estimate the salt concentrations at the membrane surface. Non-ideal thermodynamic effects from the electrolyte theory were considered to correct the activity coefficients due to the strong concentration dependence. The concentration polarization modulus and salt activities were found to substantially affect the effective local salt transport coefficients (〈em〉B〈/em〉〈sub〉〈em〉a〈/em〉〈/sub〉). At low salt concentrations, the combined result of the two effects was negligible (i.e., 〈em〉B〈/em〉〈sub〉〈em〉a〈/em〉〈/sub〉 ≈ 〈em〉B〈/em〉). However, at high feed concentrations (〉0.09 mol L〈sup〉−〈/sup〉〈sup〉1〈/sup〉 for both NaCl and NH〈sub〉4〈/sub〉Cl), the influence of the two effects was significant: the ratio 〈em〉B〈/em〉〈sub〉〈em〉a〈/em〉〈/sub〉/〈em〉B〈/em〉 ranged from 1.12 to 1.50. The concentration polarization effects on the osmotic coefficient and the effective local water transport coefficient (〈em〉A〈/em〉〈sub〉〈em〉fm〈/em〉〈/sub〉) were very small. This activity-derived model indicates that the concentration dependence of the salt and water transport in RO is a complex function of the combined effects from concentration polarization and thermodynamic non-idealities.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419310586-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): JungGil Lee, Noreddine Ghaffour〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Forward osmosis (FO) is considered as an energy-efficient process for numerous applications. Although its performance is determined by the spatially varied operation factors and the length of the channel, most of the reported simulation studies rely on length-averaged lumped models. Here, we introduce a one-D model based on heat and mass transfer and transport behavior for both bulk draw and feed channel flows. We find prediction results to be in good agreement with two different experimental results at inlet feed temperatures below 25 °C. However, the difference of water flux (J〈sub〉w〈/sub〉) and reverse salt flux (RSF) between measured and predicted data increases when both feed and draw temperatures also increase. Our theoretical simulation study first reveals that the feed temperature near the membrane active layer surface is the main factor for improving water and salt permeabilities. We find that, with a channel width of 0.3 m and a channel length of 2.5 m, J〈sub〉w〈/sub〉 and RSF calculated using the length-averaged based lumped model are overestimated by 13.01% and 13.12%, respectively, compared to those obtained using our new spatial variation model. Our study demonstrates that the length-averaged based lumped model is not an appropriate simulation model to predict the performance of large-scale FO modules at lower inlet velocities.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 468〈/p〉 〈p〉Author(s): Kasra Mohammadi, Mohammad Saghafifar, Kevin Ellingwood, Kody Powell〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Desalination market is experiencing continuous growth due to severe water scarcity in many parts of the globe. Because of the geographical coincidence of serious water scarcity and substantial direct normal irradiation potential, concentrated solar power (CSP) driven desalination presents a potential means to tackle water scarcity. Since CSPs can generate both electricity and thermal energy, they are excellent candidates to drive desalination technologies. This review article provides an overview of the status of state-of-the-art hybrid CSP-desalination systems. The paper reviews published studies on hybrid plants under two categories: only freshwater generation and cogenerating of power and freshwater. This review demonstrates that there are several potential ways to hybridize CSPs with desalination systems. Future research directions on CSP-desalination systems can be classified into researches on CSP technologies, desalination systems and integration schemes. Specifically, improvement of solar collection and desalination equipment, through cost reduction and efficiency enhancement, remains the largest hurdles to overcome. Developing novel hybrid schemes, by maximizing the thermal efficiency and minimizing the costs, offers a potential means to accelerate commercialization of such hybrid plants. Overall, the CSP-desalination plants are technically and environmentally attractive but there is still significant progress to be made for such plants to be economically feasible.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Farah Ejaz Ahmed, Raed Hashaikeh, Ali Diabat, Nidal Hilal〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The growing water demand across the world necessitates the need for new and improved processes as well as for a better understanding of existing processes. This level of understanding includes predicting system performance in scenarios that cannot always be evaluated experimentally. Mathematical modelling is a crucial component of designing new and improved engineering processes. Through mathematically modelling real life systems, we gain a deeper understanding of processes while being able to predict performance more effectively. Advances in computational capacity and the ease of assessing systems allow researchers to study the feasibility of various systems. Mathematical modelling studies enable optimization performance parameters while minimizing energy requirements and, as such, have been an active area of research in desalination. In this review, the most recent developments in mathematical and optimization modelling in desalination are discussed with respect to transport phenomena, energy consumption, fouling predictions, and the integration of multiple scaling evolution on heat transfer surfaces has been reviewed. Similarly, developments in optimization of novel reverse osmosis (RO) configurations have been analyzed from an energy consumption perspective. Transport models for membrane-based desalination processes, including relatively less understood processes such as nanofiltration and forward osmosis are presented, with recent modifications to allow for different solutes and solutions. Mathematical modelling of hybrid systems integrated with RO has also been reviewed. A survey of the literature shows that mathematical and optimization modelling of desalination processes is an exciting area for researchers in which future scholarship includes coupling of renewable energy systems with desalination technologies, as well as more advanced descriptions of fouling evolution other than that of cake filtration in membrane-based processes.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 469〈/p〉 〈p〉Author(s): Michael S. German, Hang Dong, Andrew Schevets, Ryan C. Smith, Arup K. SenGupta〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Desalination of brackish water and municipal wastewater will be integral to water resource resiliency during uncertain climate conditions. Higher efficiency and higher recovery than conventional desalination is achievable if biofouling and inorganic scaling can be avoided on membranes or heating surfaces. Temporary hardness is well addressed through acid and antiscalant dosing, but permanent sulfate hardness lacks selective removal techniques that do not require external chemicals or produce large volumes of sludge. Self-regenerating reversible ion exchange-membrane (RIX-M) processes have been proposed using a tunable anion exchange blend to remove silica and sulfate selectively from influent water with efficient regeneration via brine reject. A 2.5GPM RIX-M process was tested at the US Bureau of Reclamation (USBR) Brackish Groundwater National Desalination Research Facility (BGNDRF, Alamogordo, NM). High sulfate-containing brackish groundwater was desalinated at high recovery (80%) without membrane fouling through selective sulfate removal and regeneration via desalination brine reject, without external chemical addition. Ten treatment-regeneration cycles were performed without degradation in system performance. High efficiency silica removal from complex groundwater backgrounds at BGNDRF was also achieved across varying water chemistries. RIX-M offers a new pre-treatment opportunity to protect RO membranes from sulfate and silica fouling without dosing anti-scalants, while attaining high recovery.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419308811-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 468〈/p〉 〈p〉Author(s): Huan-Yu Shiu, Mengshan Lee, Ying Chao, Kuang-Chih Chang, Chia-Hung Hou, Pei-Te Chiueh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The ultimate goals for the advancement of capacitive deionization (CDI) are high performance and low environmental impact. The aim of this study was to obtain comprehensive knowledge on the improvement of CDIs from environmental aspects. Life cycle assessment (LCA) was utilized to evaluate the environmental friendliness of the CDIs. Five lab-scale design schemes, including CDI, membrane capacitive deionization (MCDI) and scale-up MCDI stacks, were investigated in this study. A technical performance indicator of productivity (L/h/m〈sup〉2〈/sup〉) was also employed to elucidate the efficiency of water production of the CDIs. The LCA results of the CDI stacks indicated that electricity consumption had a relatively lower overall impact (as low as 9.7%) compared to material or chemical usages (ranges from 52% to 89.8%). This result suggested that changing key materials or chemicals in improved stacks could decrease their associated impacts. Our results further pointed out the importance of the management of chemical use of 〈em〉N〈/em〉-methyl-2-pyrrolidone (NMP), the substitute for 〈em〉N〈/em〉, 〈em〉N〈/em〉-Dimethylacetamide (DMAC) in the basic CDI stack. The scale-up MCDI stacks exhibited the highest productivity of 3.62 L/h/m〈sup〉2〈/sup〉, implying that CDI has the potential to be an efficient water technology. LCA was demonstrated to support future improvement decisions for CDI with favorable environmental performance.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419307015-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 468〈/p〉 〈p〉Author(s): Paul Jacob, Tianyi Zhang, Stephanie Laborie, Corinne Cabassud〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study aimed to evaluate the effects of operating parameters (temperature (T〈sub〉f〈/sub〉), Reynolds number (〈em〉Re〈/em〉), and salinity (C〈sub〉f〈/sub〉) on wettability (contact angle, liquid entry pressure and surface free energy) and wetting indicators evaluated with the recently developed Detection of Dissolved Tracer Intrusion (DDTI) method in Vacuum Membrane Distillation (VMD) for desalination. A 0.22 μm PVDF membrane was subjected to VMD considering a large NaCl feed salinity (22 to 310 g/L). In a first step, the effects and interactions of the operating parameters on the totally wetted surface ratio (ω〈sub〉s〈/sub〉) was studied using Box Behnken design of experiments. It was shown that for salt concentrations below 166 g/L the ω〈sub〉s〈/sub〉 is low and is poorly affected by 〈em〉Re〈/em〉 and T〈sub〉f〈/sub〉, whereas for a salt concentration of 310 g/L the influence of T〈sub〉f〈/sub〉 and 〈em〉Re〈/em〉 becomes sensitive, and high T〈sub〉f〈/sub〉 and high 〈em〉Re〈/em〉 are required to avoid wetting. In a second step, the effect of salinity was evaluated as a proportion of the liquid intrusion. Here it appears that the range of salinity influences the wetting mechanisms, with an evidence of total wetting only for hypersaline concentrations (higher than 200 g/L).〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419309774-ga1.jpg" width="345" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 450〈/p〉 〈p〉Author(s): S. Aminfard, F.T. Davidson, M.E. Webber〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Wind and solar energy can potentially be used to power desalination facilities to sustainably meet growing water demands with a smaller carbon footprint than conventional approaches. This work presents a detailed method for assessing the technical and economic viability of using these renewable forms of energy to power desalination facilities. The method relies on a multi-layered, spatial model that incorporated multiple variables such as depth of water resource, salinity levels, magnitude of local renewable energy resources, distance to water infrastructure, and, for comparative purposes, the local price of water. To illustrate this method, it was applied to 1445 site locations on state of Texas lands owned by the General Land Office that overlay brackish aquifer resources. Using this method, 193 potentially economically viable sites were identified that have estimated renewable desalination water production costs lower than local municipal water prices. The results of this analysis showed that using wind to power a desalination facility is economically preferable at 145 of the 193 sites; solar was preferable at the remaining 48 sites. Solar and wind resources are both abundant in Texas; however, the particularly high capacity factors for wind across much of the state helps wind deliver the lowest cost electricity.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 460〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 1 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 461〈/p〉 〈p〉Author(s): H.N.P. Dayarathne, Sanghyun Jeong, Am Jang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉One of the major problems of seawater reverse osmosis (SWRO) process is the formation of inorganic scales (calcium carbonate, CaCO〈sub〉3〈/sub〉) and calcium sulfate, CaSO〈sub〉4〈/sub〉)) on the membrane surface, which degrades the filtration performance. Antiscalants have been applied to SWRO plants to overcome the scaling problem. In this study, we used the air micro-nano bubbles (MNBs) as a chemical-free scale inhibition method to improve the overall membrane performance in the comparison with the commercially available antiscalants. During four days of continuous experiments with MNBs, the permeate fluxes declined to 86.5(0.4)% and 83.0(0.5)% with CaCO〈sub〉3〈/sub〉 and CaSO〈sub〉4〈/sub〉 containing feed solutions, respectively. These values were higher than those obtained with the use of antiscalants in the feed water (CaCO〈sub〉3〈/sub〉–63.5(0.4)% and CaSO〈sub〉4〈/sub〉–55.8(1.0)%). Membrane fouling characterization results showed that the MNBs efficiently controlled the scaling development on the membrane surface without any chemical addition.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418307094-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 461〈/p〉 〈p〉Author(s): Abdelrahman M. Awad, Rem Jalab, Joel Minier-Matar, Samer Adham, Mustafa S. Nasser, S.J. Judd〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The current review appraises the status of forward osmosis (FO) technology implementation and prospective commercial exploitation through examination of its energy consumption and other key process attributes compared with classical desalination technologies. The outcomes of 15 studies conducted at pilot scale revealed the energy associated with the draw solution (DS) recovery to present a significant barrier to implementation of the technology, with a 40–50% decrease in energy consumption required for the DS recovery step for the process to successfully compete with classical reverse osmosis (RO) based processes. Against this, FO can be energetically favoured if deployed: (a) without the DS recovery step, i.e. osmotic concentration (OC) or fertilizer-drawn forward osmosis (FDFO), (b) in competition with evaporative desalination processes, or (c) for combined desalination and wastewater purification, when a comparatively low salinity stream is available for providing osmotic dilution (OD) of the saline feed water. Whilst these specific applications show some promise for the technology, there remains a paucity of pilot and demonstration-scale studies corroborating the theoretical energy benefit of the proposed technology configurations.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): Lutfi Agartan, Brendan Hayes-Oberst, Bryan W. Byles, Bilen Akuzum, Ekaterina Pomerantseva, E. Caglan Kumbur〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The objective of this study is to understand the effects of operating conditions and cathode parameters on the salt removal performance of hybrid capacitive deionization systems (HCDI). Hence, the effects of half cycle length, flow rate, cathode thickness, and conductive additive loading in the cathode are systematically investigated. Hydrothermally synthesized α-MnO〈sub〉2〈/sub〉 was selected as the active material in the cathode. Desalination results indicate notable dependence of HCDI performance on the investigated parameters. For instance, increasing half cycle length increases the salt adsorption capacity (SAC) by ~58% but decreases the peak salt adsorption rate (PSAR) by ~28%. On the other hand, increasing the flow rate leads to an increase of the SAC and PSAR by ~25% and ~115%, respectively. Increase in the cathode thickness also showed a notable decay in performance with 43% drop in SAC. The amount of conductive additive in the cathode was also investigated to observe the impact of electrical conductivity on the CDI performance. Salt adsorption capacity and rate of HCDI systems containing identical active materials show strong dependence on the operation conditions and cathode parameters, which suggests a necessity of developing an understanding of the impact of these conditions on the system performance.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418317260-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): Ahmed Fuwad, Hyunil Ryu, Jun-Hee Lee, Daejoong Kim, Yeong-Eun Yoo, Young-Rok Kim, Sun Min Kim, Tae-Joon Jeon〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Membrane technology has been dominating the water desalination industry for decades due to its high efficiency and reliability. However, conventional membrane materials present performance limitations; thus, the demand for the development of new material is high. In recent years, aquaporin biomimetic membranes have emerged as a next-generation water desalination platform based on natural phenomena. Aquaporin is a natural water-selective protein that possesses exceptional water selectively and permeability properties. However, aquaporin must be embedded in an amphiphilic structure, such as a cell membrane, and the mimetic structure and stability of these environments represent key factors for successful water purification systems. Herein, we report an electrokinetic approach that stabilizes the aquaporin-containing membranes on a porous substrate under an applied electric field, resulting in an exceptionally stable and uniform biomimetic membrane on a solid support. The surface morphological analysis shows that the liposomes retained their perfect shape and size and did not present fusion or aggregation. Moreover, under forward osmosis, our membrane presents a salt rejection rate that reached 97.8 ± 0.7% with 7.45 ± 0.62 Lm〈sup〉−2〈/sup〉h〈sup〉−1〈/sup〉 (LMH) of water flux.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001191641831261X-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 453〈/p〉 〈p〉Author(s): Xu Su, Wende Li, Alan Palazzolo, Shehab Ahmed〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Experiments and Computational Fluid Dynamics (CFD) simulations were performed to investigate the colloidal fouling control of a vibration enhanced reverse osmosis (VERO) membrane system for up to 12 h of operation time. A porous cake mass transfer model for the reverse osmosis (RO) colloidal fouling analysis was derived by combining the cake filtration model, cake enhanced osmotic pressure (CEOP) effect, the critical flux theory, and the solute convection-diffusion model. The process of colloidal particle deposition and fouling formation on the membrane surface were visualized using this model. The permeate flux variation and cake layer distribution along the membrane were depicted. Systematic studies including different initial permeate fluxes, Reynolds numbers, particle concentrations, and vibration frequencies were carried out to investigate the system performance under different operation conditions. The results suggest that colloidal fouling induced permeate flux decline could be improved by the high-frequency vibration in the VERO module. Both simulations and experiments demonstrated that, with a fixed vibration amplitude, membrane module with higher vibration frequencies will have less 〈em〉NaCl〈/em〉 accumulation and higher permeate flux under the influence of colloidal fouling.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 453〈/p〉 〈p〉Author(s): Clare Bales, Peter Kovalsky, John Fletcher, T. David Waite〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Research into desalination of groundwaters for agricultural application in Australia has previously focused on the viability of large scale reverse osmosis plants. Capacitive Deionization (CDI) is an alternative method of desalination that has been demonstrated to be effective for desalting moderately saline (brackish) waters in pilot studies and can be powered using photovoltaics. Using a farm scale economic model coupled to a CDI performance model, potentially viable agricultural applications for CDI have been identified with variation in crop type and CDI configuration enabling optimisation. Scenarios for grapes, oranges, almonds, apples and tomatoes were modelled with maximum internal rates of return (IRR) and annualised profits (AUD$/ha/yr) determined. Groundwater bore salinity thresholds above which the regime is not feasible were found to be 4.2 dS/m for grapes, 5.5 dS/m for oranges, 4.4 dS/m for almonds, 14 dS/m for apples and 8.5 dS/m for tomatoes for a 60 ha crop with an investment period of 10 years. Costing of CDI desalinated water was scenario dependent with a large portion falling below AUD$1/kL. CDI desalination was found to be economically feasible for a range of scenarios and should be explored further as an option to assist with global water and food security concerns.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): Mehzabeen Mannan, Mohamed Alhaj, Abdel Nasser Mabrouk, Sami G. Al-Ghamdi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Comprehensive environmental impact of thermal desalination is poorly understood in Middle Eastern and North African region, especially for multistage flash (MSF) desalination. Nearly 75% of Qatar's municipal water supply is being produced by MSF due to process reliability and other advantages, which is highly energy-intensive and creates an enormous environmental burden. Hence, this paper aimed to develop a multi-faceted, life-cycle based framework that quantifies the overall environmental and human health impacts of MSF desalination in Qatar. Three different MSF systems were examined by varying the gain ratio (GOR) through life cycle assessment. Different environmental loads were examined and evaluated, including climate change, freshwater eutrophication, fossil fuel depletion, ozone depletion, and human toxicity. The results showed that the modified MSF configuration with higher GOR released 7.32 kg CO〈sub〉2〈/sub〉 for 1 m〈sup〉3〈/sup〉 of water production while the plant with lowest GOR released 12.6 kg. Quantitative analysis of the environmental degradation caused by desalination reflects the reality of water use in Qatar and can motivate users to reduce their water consumption as part of the Qatar's national vision 2030. The implication of this study is particularly important at a regional level as it serves as a preliminary baseline for a more efficient water strategy.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): H. Xu, Y. Zhao, Y.J. Dai〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉On-going study on the humidification-dehumidification (HDH) desalination has proved that internal heat recovery is a significant and potential method for improving the system performance and reducing the fresh water cost. In this paper, a novel solar assisted heat pump (SAHP) with internal heat recovery desalination system based on HDH process is proposed and studied experimentally. The objective of this study is to investigate the ability of heat recovery in improving the system performance and obtain the optimal operating parameters. Based on the experimental results, it can be concluded that the fresh water cost of the two-stage HDH desalination system is reduced by 17.36%, and system productivity and gained-output-ratio (〈em〉GOR〈/em〉) are increased by 15.51% and 55.64%, respectively compared with those of the single-stage. Particularly, benefiting from energy cascade utilization, the distribution ratio is introduced to further improve the system performance, which is affected strongly by the cooling seawater flow rate. Furthermore, a comparison of the humidifier materials between plastic polyhedron empty balls (PPEBs) and honey-comb paper indicates that the increment in system productivity by PPEBs is 27.76% lower than that by honey-comb paper with a reasonable specific surface area.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): J. Jaime Sadhwani, M. Sagaseta de Ilurdoz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The production of desalinated water generates multiple environmental impacts of different kinds. One of the most harmful indirect environmental impacts is derived from energy consumption, especially when the sources of energy used have their origin in fossil fuels. In the production of electrical energy in isolated island systems without electric system interconnections (either with other islands or with continental grids) and with limited renewable energy resources, the predominance of fossil fuels is common in the generation of the electrical power required to meet the global needs of the island system. This paper aims to analyse the indirect environmental impact of the origin of the energy used to obtain desalinated water in Gran Canaria. The result shows the indirect environmental impact generated have representative ranges, reaching 1.46 kg of fossil fuels per m〈sup〉3〈/sup〉 of water desalinated in the worst case of 2015. This reflects the need to reduce the desalination water demands, improve the efficiency plants and promote the tandem “renewable energy-desalination”, as proposed in it. This island can be considered a good example of an isolated island location situated in a temperate subtropical climate with severe water limitations, where production of this industrial resource is of extreme importance.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Yi Li, Shishi Yang, Kaisong Zhang, Bart Van der Bruggen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Two dimensional (2 D) layered materials with special properties provide opportunities to design energy-efficient membranes for water desalination. A negatively charged layered graphene analogue, molybdenum disulfide (MoS〈sub〉2〈/sub〉) was synthesized through liquid exfoliation. A novel thin film nanocomposite (TFN) reverse osmosis (RO) membrane was successfully fabricated with prepared laminar MoS〈sub〉2〈/sub〉 as fillers in the organic phase through interfacial polymerization of 〈em〉m〈/em〉-phenylenediamine and trimesoyl chloride monomers. The laminar MoS〈sub〉2〈/sub〉 nanosheets were observed by transmission electron microscopy (TEM), and the nanosheets were dispersed in the polyamide (PA) matrix as well as on the membrane surface. The properties of the resultant TFN membranes were effectively modified by taking the advantage of two dimensional features, i.e., the negative charge and the hydrophilic sites of layered MoS〈sub〉2〈/sub〉. Compared to a classical TFC membrane, the MoS〈sub〉2〈/sub〉 incorporated TFN membranes were found to have an increased salt rejection and higher water flux. Moreover, 0.01 wt% MoS〈sub〉2〈/sub〉-TFN membrane showed a superior fouling resistance against proteins as foulants. The antifouling behavior of this TFN membrane was observed by field-emission scanning electron microscopy (FE-SEM). Stability tests demonstrated that there was a loss of MoS〈sub〉2〈/sub〉 in the initial 2 h filtration, but the process is stable in the long-term.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418311950-ga1.jpg" width="391" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 453〈/p〉 〈p〉Author(s): Mohammed J.A. Hamad, Evans M.N. Chirwa〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Polydiallyldimethylammonium Chloride (PolyDADMAC) is a cationic polyelectrolyte utilised widely in drinking water industry. This study has evaluated the performance of cationic organic polyelectrolyte PolyDADMAC and its monomer DADMAC as osmotic agents in Forward Osmosis (FO) process. The properties of PolyDADMAC and DADMAC draw solutions were initially studied. Thereafter, a series of experiments were conducted to examine the efficiency of these solutions for water recovery using CTA and Aquaporin flatsheet membranes under FO mode. The results show a high electrical conductivity of both draw solutions due to the presence of strong cation electrolyte (〈em〉C〈/em〉〈sub〉8〈/sub〉〈em〉H〈/em〉〈sub〉6〈/sub〉〈em〉N〈/em〉〈sup〉+〈/sup〉) in solutions. The obtained water flux and reverse solute diffusion of DADMAC were higher than PolyDADMAC at same concentrations. Factors contributing to the change of water flux and reverse solutes diffusion through membranes were addressed. CTA membranes accomplished higher water flux than the aquaporin membranes, however; the latter was more selective and provided better results of reverse solutes diffusion. Diluted draw solutions were reconcentrated via Nanofiltration-system. High ion rejection of DADMAC (96%) and poor ion rejection of PolyDADMAC (85%) were observed. Lastly, this article introduced a valuable comparison between cationic polyelectrolyte and its electrolyte based on their behaviours as draw solutes in FO process.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418309834-ga1.jpg" width="334" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Peyman Zanganeh, Ataallah Soltani Goharrizi, Shahab Ayatollahi, Mehrzad Feilizadeh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Wettability is one of the most important factors which significantly influences solar still efficiency. Moreover, it determines the condensation mode, i.e., filmwise or dropwise condensation. In the present study, materials with different wettability were applied as the condensing surface to evaluate the effect of wettability on the distillate production of a single slope solar still. To compare the effects of dropwise and filmwise condensation on the condensate yield, the wettability of the condensing surface was changed by applying a nano-silicon solution according to a dip coating technique. All the experiments were conducted at three surface inclination angles. The results revealed that the nano-coating changed the condensation mechanism from filmwise to dropwise for all the materials. Also, it was concluded that dropwise condensation leads to increased condensate production at higher surface inclination angles. For example, condensate production of a glass surface was increased by 23% after nano-coating at a surface inclination angle of 50°. In addition, the amount of dripping was estimated before and after the coating process by using additional collectors. To illustrate, the amount of dipping from uncoated aluminium surface was 106 ml which increased to 198 ml after the coating process at a surface inclination angle of 30°.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001191641831662X-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 453〈/p〉 〈p〉Author(s): M. Micari, A. Cipollina, F. Giacalone, G. Kosmadakis, M. Papapetrou, G. Zaragoza, G. Micale, A. Tamburini〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The coupling of Reverse Electrodialysis with Membrane Distillation is a promising option for the conversion of waste heat into electricity. This study evaluates the performances of the integrated system under different operating conditions, employing validated model and correlations. This work provides a detailed description of the behaviour of a real RED-MD heat engine and indicates the set of inlet concentrations, velocities and equipment size which returns the highest cycle exergy efficiency. These operating conditions were selected for the pilot plant developed within the EU-funded project RED Heat to Power. For the first time, a perspective analysis was also included, considering highly performing RED membranes and future MD module. Relevant results indicate that technological improvements may lead to interesting system performance enhancement, up to an exergy efficiency of 16.5%, which is considerably higher than the values reported in literature so far.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418317557-ga1.jpg" width="310" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 453〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 453〈/p〉 〈p〉Author(s): Farah Ejaz Ahmed, Raed Hashaikeh, Nidal Hilal〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Growing water demands have led to rapidly increasing desalination installation capacity worldwide. In an attempt to lower carbon footprint resulting from high-energy consuming desalination processes, attention has shifted to using renewable energy sources to power desalination. With solar irradiation ample in regions that heavily rely on desalination, solar powered desalination provides a sustainable solution to meeting water needs. The compatibility of each desalination process with the solar technology is driven by whether the kind of energy needed is thermal or electrical, as well as its availability. With rapid advances in solar energy technologies – both photovoltaic and solar thermal, there has also been growing interest in coupling solar energy with desalination, with a focus on improving energy efficiency. In this review, the most recent developments in photovoltaic powered reverse osmosis (PV-RO), solar thermal powered reverse osmosis (ST-RO) are discussed with respect to membrane materials, process configuration, energy recovery devices and energy storage. In addition, advances in new materials for solar powered membrane distillation (MD) and solar stills in the past two years have also been reviewed. Future outlook considers the use of hybrid renewable energy systems as well as solar powered forward osmosis and dewvaporation. Solar powered desalination systems have been analysed with emphasis on technological and energy consumption aspects.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Michael Heihsel, Manfred Lenzen, Arunima Malik, Arne Geschke〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study examines greenhouse gas emissions for 2005–2015 from seawater desalination in Australia, using conventional energies. We developed a tailor-made multi-regional input-output-model. We complemented macroeconomic top-down data with plant-specific desalination data of the largest 20 desalination plants in Australia. The analysed capacity cumulates to 95% of Australia's overall seawater desalination capacity. We considered the construction and the operation of desalination plants. We measure not only direct effects, but also indirect effects throughout the entire value chain. Our results show the following: We identify the state of Victoria with the highest emissions due to capital and operational expenditures (capex and opex). The contribution of the upstream value chain to total greenhouse gas emissions increases for capex and decreases for opex. For capex, the construction of intake and outfall is the driving factor for carbon emissions. For opex, electricity consumption is the decisive input factor. Both in construction and operation, we identify the critical role of the electricity sector for carbon emissions throughout the supply chain effects. The sector contributes 69% during the zenith of the construction phase and 96% during the operating phase to the entire emissions. We estimate the total emissions for 2015 at 1193 kt CO〈sub〉2〈/sub〉e.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Hye-Won Kim, Taekgeun Yun, Peter K. Kang, Seungkwan Hong, Seongpil Jeong, Seockheon Lee〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A visualization system was designed for a real-time observation of scales during direct contact membrane distillation (DCMD). The system was composed of a MD module, a camera and light sources. Firstly, visibility of the scales with the system and correlation between detected spots and wetting were assessed during the MD process using a polyvinylidene fluoride (PVDF) 0.45 μm membrane. The white spots were observed in the captured images from the visualization system and got broader with the electrical conductivity (EC) increase in permeate. It was verified that the spots indicated the pores blocked by the CaSO〈sub〉4〈/sub〉 scales. The wetting occurred through the white spots if the pressure was applied. Therefore, the high wetting potential area could be identified with the suggested visualization system during the MD operation in real-time. The visualization system was applied to the MD process under different permeate temperatures (20 and 55 °C). The visualization system successfully detected the pore blocking related with different scale formation according to the temperatures at the membrane surface.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418314164-ga1.jpg" width="325" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Zuoyou Zhang, Xuewei Du, Kenneth H. Carlson, Cristian A. Robbins, Tiezheng Tong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We developed an integrated treatment train that enables effective treatment of shale oil and gas produced water generated from the Wattenberg field in northeast Colorado. Membrane distillation (MD) was performed in tandem with simple and inexpensive pretreatment steps, namely precipitative softening (PS) and walnut shell filtration (WSF). PS removed various particulate, organic, and inorganic foulants, thereby mitigating fouling and scaling potential of the produced water. WSF displayed exceptional efficiencies (≥95%) in eliminating volatile toxic compounds including benzene, ethylbenzene, toluene, and xylenes (BTEX) along with additional gasoline and diesel range organic compounds. With pretreatment, the water vapor flux of MD decreased by only 10% at a total water recovery of 82.5%, with boron and total BTEX concentrations in the MD distillate meeting the regulatory requirements for irrigation and typical discharge limits, respectively. The use of pretreatment also led to robust membrane reusability within three consecutive treatment cycles, with MD water flux fully restored after physical membrane cleaning. Our results highlight the necessity of pretreatment prior to MD treatment of produced water and demonstrate the potential of our treatment train to achieve a cost-effective and on-site wastewater treatment system that improves the sustainability of the shale oil and gas industry.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418319714-ga1.jpg" width="402" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Kai Luo, Yu-xiang Jia, Xin-xin Liu, Meng Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Electrodialysis (ED) technology has been paid special attention in reclamation of high salinity effluents. Therein, the attempts on how to separate out scale-forming cations are never ending. Different from a conventional scheme, an on-line endowment of mono-cation permselectivity to a conventional ED stack was put forward in this work by electro-deposition of branched polyethyleneimine with an optimized molecular weight. Subsequently, series of work performances, including limiting current, mono-cation permselectivity, permselectivity between specific anions, water transport behavior, current efficiency and energy consumption, were investigated in reclamation of a typical saline wastewater. The pilot-scale ED experiments showed that the modified ED stack displayed a significant mono-cation permselectivity, for examples, 〈em〉P〈/em〉〈sub〉〈em〉Na〈/em〉〈sup〉+〈/sup〉〈/sub〉〈sup〉〈em〉Ca〈/em〉〈sup〉2+〈/sup〉〈/sup〉 and 〈em〉P〈/em〉〈sub〉〈em〉Na〈/em〉〈sup〉+〈/sup〉〈/sub〉〈sup〉〈em〉Mg〈/em〉〈sup〉2+〈/sup〉〈/sup〉 were reduced from 0.36 and 0.81 to 0.11 and 0.12, respectively. Interestingly, a certain permeability priority for SO42- was also achieved at the same time. Moreover, the five-month service life tests indicated the ED stack can maintain a stable separation performance. On the other hand, some problems induced by the modification were also revealed, such as the facilitated water transport and the increase of energy consumption. Anyway, it is reasonable to believe that the scheme should have broad and promising application perspectives due to its effectiveness, economy and simplicity.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Sergio G. Salinas Rodriguez, Nizordinah Sithole, Nirajan Dhakal, Margot Olive, Jan C. Schippers, Maria D. Kennedy〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉For assessing the particulate fouling of water, the modified fouling index (MFI〈sub〉0.45〈/sub〉) is a superior test to the silt density index (SDI). There is a need to compare both tests in terms of sensitivity, how they are affected by the filter material and the type of support plate and also illustrate their use for monitoring of seawater quality over time. In this work, we studied seven different filter holders with different filter support plates and three different 0.45 μm filter materials, and we applied the tests for monitoring of North Sea water quality. The results illustrated that the type of support plate of the filter holder greatly influences the measured MFI〈sub〉0.45〈/sub〉 values and thus, a correction for the effective membrane area may be needed when carrying out an MFI〈sub〉0.45〈/sub〉 test. An attempt to normalize differences in MFI〈sub〉0.45〈/sub〉 due to filter material with a Formazin solution was tested but proven not successful. When monitoring the seawater, the MFI〈sub〉0.45〈/sub〉 was much more sensitive than SDI to water quality variations in particular during algal growth. As the SDI and MFI〈sub〉0.45〈/sub〉 tests can be measured with help of the same equipment, more alignment in the ASTM protocols for both methods is recommended.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 454〈/p〉 〈p〉Author(s): Mohammad Esrafilian, Rouhollah Ahmadi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this investigation, a polygeneration scheme integrating local desalination units with CCHP systems, providing cold, heat and power for Kish twin towers as well as providing a portion of the fresh water demand of the island, is proposed and evaluated in terms of energy, environment, and economy aspects. The proposed system is compared to the conventional CCHP and desalination system adopting the separate production system as the reference. Here, two types of desalination technologies, namely multi-effect distillation (MED) and reverse osmosis (RO) processes, are used to provide desalinated water. A genetic algorithm is implemented to determine the optimal operating parameters. It results in that in the polygeneration system the yearly average power generation efficiency, the annual primary energy saving ratio (APESR) and the annual total cost saving ratio (ATCSR) of the whole system increase by 3.45%, 9.73%, and 6.49%, respectively, compared to the conventional system. Using the MED process can increase the ATCSR from 9.8% to 16.0%, depending on the fresh water market price. Moreover, the carbon dioxide emission (CDE) decreases by 1460.5 tons each year, compared to the reference. It is also indicated that 93.87% of the MED input heat can be recovered for domestic hot water (DHW) provision.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 452〈/p〉 〈p〉Author(s): David W. Bian, Sterling M. Watson, Natasha C. Wright, Sahil R. Shah, Tonio Buonassisi, Devarajan Ramanujan, Ian M. Peters, Amos G. Winter〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper presents the cost optimization of a photovoltaic-powered electrodialysis reversal (PV-EDR) system for village-scale applications in rural India based on current component costs and performance. A PV-EDR alternative was explored because it requires half the specific energy (and thus half the power system cost), and reduces water wastage from 60% to less than 10%, compared to small-scale reverse osmosis (RO) systems for groundwater salinity levels commonly found in India. Through co-optimization of the PV and EDR subsystems, the optimal system was predicted to cost $23,420 (42% less than a system designed using conventional engineering practice). A key to the cost reduction was flexible water production that accommodates daily changes in solar irradiance with overproduction on sunny days and water buffer storage tanks. A sensitivity analysis revealed that the capital cost of the total system is most sensitive to membrane area; reducing membrane cost by 87% would half the system capital cost. The optimization method presented here, as well as the cost saving strategies of time-variant operation and load matching with solar irradiance availability, provide design strategies that are relevant to other PV-EDR architectures and general off-grid desalination applications.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 471〈/p〉 〈p〉Author(s): R. López-Zavala, N. Velázquez, L.A. González-Uribe, K.M. Quezada-Espinoza, J.A. Aguilar-Jiménez, S. Islas, M. Nakasima-López, E. González〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper presents a novel cooling and desalination system that uses seawater as coolant, and that has a high energetic and internal mass integration, as well as higher capacity and efficiency levels. The proposed system was simulated using Aspen Plus software; its operative behavior was also evaluated in order to prove its technical feasibility. Using a 23 kW simple-effect absorption cooling machine as a basis, and utilizing the produce of desalination as coolant, this technological approach increases the system's capacity by a factor of 87.4, to 2012 kW. It also increases the COP value to 6.15, 8.54 times greater than the 0.72 COP reported for this type of systems. Furthermore, the system produces 73,569 L/day of water, with an RR of 0.56 and a PR of 6.63. The proposed technology presents a setup that allows for a high energetic and internal mass integration, which increases the system's capacity and efficiency.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 474〈/p〉 〈p〉Author(s): Biaowen Wei, Jiancong Pan, Jun Feng, Caidi Chen, Shijun Liao, Yigang Yu, Xiuhua Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A series of series-connected dication ionic ionomers with flexible hydrophobic tails (QPTs) designed for electrodialysis desalination (ED) anion exchange membranes have been synthesized successfully from a monoionic quaternization agent 〈em〉N〈/em〉-(2-(dimethylamino)ethyl)-〈em〉N〈/em〉,〈em〉N〈/em〉-dimethylhexan-1-aminium bromide and brominated poly(2,6-dimethyl-1,4-phenylene oxide). The properties of QPTs membranes were evaluated in terms of ion exchange capacity (IEC), water uptake (WU), swelling ratio (SR), thermal stability, membrane area resistance (R〈sub〉m〈/sub〉), permselectivity (P) and ED experiments. The results confirm that the coaction of the series-connected dications linking by a short chain of two methylene groups and the middle length aliphatic tails offers QPTs excellent conductivity and permselectivity simultaneously. Especially, QPT-4 membrane has an excellent permselectivity of 94.0% and the lowest R〈sub〉m〈/sub〉 of 1.60 Ω cm〈sup〉2〈/sup〉 at the highest IEC of 2.33 mmol g〈sup〉−〈/sup〉〈sup〉1〈/sup〉. Moreover, QPT-4 membrane shows the best ED performances with current efficiency of 89.14%, salt flux of 75.57 mg m〈sup〉−〈/sup〉〈sup〉2〈/sup〉 s〈sup〉−〈/sup〉〈sup〉1〈/sup〉 and energy consumption of 2.16 kWh kg〈sup〉−〈/sup〉〈sup〉1〈/sup〉 in the mostly reported NaCl ED system, which are much higher than those of commercial TWEDA1 (the corresponding values of 83.96%, 71.19 mg m〈sup〉−〈/sup〉〈sup〉2〈/sup〉 s〈sup〉−〈/sup〉〈sup〉1〈/sup〉 and 2.67 kWh kg〈sup〉−〈/sup〉〈sup〉1〈/sup〉). The excellent ED stability in the repeated tests further qualifies QPT-4 to be a very promising candidate for ED application.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉A series of series-cond dication anion exchange membranes appending flexible hexyl tails (QPTs) were tailored successfully for electrodialysis desalination (ED). The QPTs membranes have good conductivity and permselectivity simultaneously and display superior ED performances to that of commercial TWEDA1.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001191641931210X-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Bastiaan Blankert, Youngjin Kim, Hans Vrouwenvelder, Noreddine Ghaffour〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉A facultative hybrid reverse osmosis (RO) – pressure retarded osmosis (PRO) system can switch its operation between i) RO mode, where high quality water is produced from waste-water treatment plant effluent and ii) PRO mode, where the salinity difference between seawater desalination brine and wastewater is converted to energy. This system takes advantage of fluctuating energy pricing, by consuming low cost energy to produce water and producing high value energy.〈/p〉 〈p〉The system was modeled by a local concentration polarization and solution diffusion model, considering several geometries. The system was optimized and for different ratios of the economic value of electricity vs water, to find process settings and switch points. A necessary condition for the feasibility of the facultative hybrid RO-PRO concept is that the permeate value satisfies: i) low enough, to justify electricity production and ii) high enough, to justify water production. With a maximum energy price of 0.25 USD/kWh, the first condition translates into 〈0.10–0.17 USD/m〈sup〉3〈/sup〉 (ALFS) or 〈0.20–0.28 USD/m〈sup〉3〈/sup〉 (ALDS). The facultative hybrid RO-PRO concept is only feasible as improvement to a PRO system, where there is a limited demand for purified WWTP-effluent. It is expected that it is usually preferred to produce purified WWTP-effluent.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419318831-ga1.jpg" width="238" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Lijia Liu, Yueguang Fang, Yujiang Meng, Xinyi Wang, Fuqiu Ma, Chunhong Zhang, Hongxing Dong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Here, reaction of a chloromethylated metal-organic framework (MOF) MIL-101 with diaminomaleonitrile (DAMN) following with an amidoximation reaction successfully produced a novel amidoxime functionalized porous material (〈strong〉MIL-101-AO〈/strong〉). The chelation of amidoxime group to uranium and the large specific surface area afforded 〈strong〉MIL-101-AO〈/strong〉 excellent selective adsorption ability for U (VI) in aqueous solutions (586 mg·g〈sup〉−〈/sup〉〈sup〉1〈/sup〉). Furthermore, 〈strong〉MIL-101-AO〈/strong〉 showed much stronger selective adsorption for U (VI) than other co-existing metallic ions in the artificial seawater (removal rate reached 96%). The influence factors on the adsorption process were evaluated by batch adsorption experiments under different condition. The process of adsorbing uranium on 〈strong〉MIL-101-AO〈/strong〉 fitted with the Langmuir model and the pseudo-second-order kinetic model. The △H° and △G° values of uranium adsorption indicated that it was an endothermic heat process; a higher adsorption temperature could promote the adsorption on 〈strong〉MIL-101-AO〈/strong〉. All the experimental results indicated that 〈strong〉MIL-101-AO〈/strong〉 was an adsorbent with the application value of extracting uranium in seawater.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Lin Xu, Shiming Xu, Xi Wu, Ping Wang, Dongxu Jin, Junyong Hu, Lei Li, Le Chen, Qiang Leng, Debing Wu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effectiveness-number of transfer units (〈em〉ε〈/em〉-NTU) method was used to develop the heat and mass transfer model of air-gap diffusion distillation (AGDD). In this model, the latent heat transfer of vapor in air-gap was regarded as an equivalent convective heat transfer to make a relationship with NTU. Compared with the full numerical model developed in our previous work, the new model was simple and performing with dramatic high computational efficiency. The accuracy of the model was as well as the full numerical model. The influences of structure and operation parameters on the performances of AGDD system were discussed furtherly by employing the model. Results shown that the air-gap height, the inlet temperature and feed flow rate of hot stream could be regarded as the strong parameters effected significantly on the performances of the system in comparison with the air-gap thickness and inlet temperature and salt concentration of cold stream. Therefore, these strong parameters should be considered firstly for improving the heat and mass transfer of AGDD.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Li Feng, Jin Li, Haoran Ma, Guanghao Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A sequencing batch reactor (SBR) was used to study enhanced nitrogen removal of marine anammox bacteria (MAB) treating nitrogen-laden saline wastewater with Fe(II) addition. The reactor was operated at 15 °C with influent pH of 7.5 ± 0.1. At 4 mg/L Fe(II), ammonia removal rate (ARR) and nitrite removal rate (NRR) increased to 0.85 and 0.90 kg/(m〈sup〉3〈/sup〉·d), respectively. Specific anammox activity (SAA) sharply increased to 0.76 kg/(kg·d). Both marine anammox and marine Feammox reaction occurred simultaneously. ΔNO〈sub〉2〈/sub〉〈sup〉−〈/sup〉-N/ΔNH〈sub〉4〈/sub〉〈sup〉+〈/sup〉-N was lower than theoretical ratio due to marine Feammox. When Fe(II) was 〉25 mg/L, the maximal substrate conversion rate increased from 2.97 to 3.47 kg/(m〈sup〉3〈/sup〉·d) within 1 h. High Fe(II) concentration (〉 25 mg/L) had no negative effect on marine anammox but could inhibit marine Feammox process. The optimal Fe(II) dose was 25 mg/L for marine Feammox. The remodified Logistic model was appropriate to analyze nitrogen removal independent of Fe(II) concentration, and the modified Boltzmann model could only be used to analyze nitrogen removal at high Fe(II) concentration. At 10 mg/L Fe(II), the fitted 〈em〉λ〈/em〉 value declined from 0.52 h to 0.34 h. The lag time of MAB was shorten greatly.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Qiuming Ma, Aras Ahmadi, Corinne Cabassud〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This work aims to design a small-scale desalination unit for producing drinking water in remote places (~2 L/person). It considers an equipment where vacuum membrane distillation (VMD) and direct solar heating through solar flat-plate collector (FPC) are coupled within the same intensified module, with photovoltaic (PV) panels providing electricity. An adapted heat pumping strategy is conceived to bridge between the heat-demanding feed recirculation and the heat-releasing vapor condensation, aiming both to recover latent heat of evaporation and to condense vapor without using an additional intensive cooling system. Sensitivity analyses and multi-objective optimizations are provided, based on water production and electric consumption of both pumping and cooling, to orientate the design and to discuss the key issues for an optimal operation. Results reveal that for a tiny module (0.18 m〈sup〉2〈/sup〉), a daily freshwater production of 3.7 L can be obtained with an average electric consumption of 17 W (~0.13 m〈sup〉2〈/sup〉 PV). At a relatively bigger scale (3 m〈sup〉2〈/sup〉), 96 L of freshwater is attained at a consumption of 449 W (~3.26 m〈sup〉2〈/sup〉 PV). The need for PV power capacity per unit water production is almost constant, ranging in 4.2–5 W L〈sup〉−〈/sup〉〈sup〉1〈/sup〉.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916419318867-ga1.jpg" width="316" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Luopeng Yang, Linhua Zhang, Angui Li, Jinyan Wu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Non-condensable gas (NCG) released in the multi-effect distillation associated with a thermal vapor compression (MED-TVC) seawater desalination seriously deteriorates the heat transfer efficiency. Due to the complicated coupled nature between NCG desorption and heat transfer process, little attention has been paid to local NCG desorption conditions which contribute to improving thermal efficiency of MED-TVC. Chemical desorption continuously releases more CO〈sub〉2〈/sub〉 than O〈sub〉2〈/sub〉 and N〈sub〉2〈/sub〉 released by physical desorption. A numerical model, considering heat and mass transfer, flow dynamics and chemical reactions, predicts chemical reaction time, evaporation rate and CO〈sub〉2〈/sub〉 desorption rate for varying thermal and geometrical parameters. The predicted CO〈sub〉2〈/sub〉 desorption rate is in a good agreement with the running data of a venting system in a reference MED-TVC desalination plant. An increasing evaporation temperature, which results in a decrease in chemical reaction time and element volume, contributes to decreasing a specific CO〈sub〉2〈/sub〉 desorption rate. With an increase in inlet heating steam velocity, the specific CO〈sub〉2〈/sub〉 desorption rate decreases due to the increasing element volume and decreasing specific evaporation rate. The specific CO〈sub〉2〈/sub〉 desorption rate increases with an increase in tube diameter and a decrease in dimensionless tube pitch due to the opposite effects of heat transfer and element volume.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Jia-nan Zheng, Mingjun Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Freshwater scarcity has been troubling the high-quality development of many countries and regions, and seawater desalination is a vital source of freshwater. Recently, gas hydrate based desalination (GHBD) technology attracts much attention because of bringing no extra pollution to water. We developed a novel multifunctional desalination apparatus via gas hydrate with various operation modes and separation methods. In this study, the desalination characters under different separation modes were conducted using simulated seawater, and the hydrate-purging method with a desalination efficiency of more than 80% was selected to desalt the natural seawater sample. In addition, the purging method can greatly improve the desalination effects of both squeezed hydrate column and loose hydrates. The experimental results indicate that the removal efficiencies of different ions in the seawater were similar and their difference was related to the strength of ionic hydration. And above all, we designed and conducted a continuous desalination process including multiple injection, separation, washing and purging operations. The ultimate desalination efficiency using hydrate-purging method was over 80%, and the freshwater recovery was above 30% with 200 mL initial seawater in this study. The experimental proposal and results of this study are of great significance to the development of GHBD technology.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 478〈/p〉 〈p〉Author(s): Lijing Bai, Jin Li, Basanta Kumar Biswal, Guanghao Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nitrogen removal performance and key enzyme activities of “〈em〉Candidatus〈/em〉 Brocadia sinica” with sorbitol addition were investigated in nitrogen-laden saline wastewater treatment. Nitrogen removal through “〈em〉Candidatus〈/em〉 Brocadia sinica” first increased and then decreased with sorbitol addition. Optimal ammonia removal rate and nitrite removal rate were 0.53 and 0.67 kg/(m〈sup〉3〈/sup〉·d) at 0.8 mM sorbitol, which increased by 39.5% and 71.8%, respectively. Moreover, appropriate sorbitol content could resist salt stress and decrease extracellular polymeric substances content of “〈em〉Candidatus〈/em〉 Brocadia sinica”. Independent of sorbitol concentration, hydrazine dehydrogenase and nitrite reductase activities were enhanced about 1.37–2.36 folds. Remodified Logistic model was the most appropriate to analyze nitrogen removal process with sorbitol addition. Fitted 〈em〉R〈/em〉〈sub〉〈em〉max〈/em〉〈/sub〉 (%/h) could be converted into 〈em〉V〈/em〉〈sub〉〈em〉max〈/em〉〈/sub〉 (kg/(m〈sup〉3〈/sup〉·d)) to predict optimal substrate conversion rates of “〈em〉Candidatus〈/em〉 Brocadia sinica” treating nitrogen-laden saline wastewater with various sorbitol contents.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 460〈/p〉 〈p〉Author(s): Amal Kanta Giri, Filipe Teixeira, M. Natália D.S. Cordeiro〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Recently, water transport through graphene oxide (GO) nanochannels has gained much attention because of its potential applications in desalination and water filtration. In this work, molecular dynamics (MD) simulations were carried out to elucidate the filtration efficiency and water structure in GO nanochannels of varying oxidation degree (from 0% to 40%) and interlayer spacing (from 0.6 nm to 1.0 nm). The results from these simulations show that ion permeation is observed in 1.0 nm channels, but ion rejection is close to complete for the narrower channels, irrespective of the degree of oxidation. Furthermore, water permeation increases with increasing interlayer separation and decreases with increasing oxidation degree. In general, water molecules prefer flowing through unoxidized regions of the narrower channels, but show no preferential path when flowing through the wider ones. Moreover, the analysis of the interaction between water molecules and the hydroxyl groups inside the GO channel shows that OH groups play a vital role disrupting the solvation sphere of the salt ions. However, with increasing oxidation of the GO wall, the formation of intra-layer hydrogen bonds becomes relevant, decreasing the overall number of hydrogen bonds involving water molecules, and thus preventing further decrease of the water permeance. To sum up, our results indicate that the best GO channel for the desalination is the one with interlayer spacing 0.8 nm and oxidation degree of 10% or lower.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 May 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 458〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 1 June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 459〈/p〉 〈p〉Author(s): Pankaj Dumka, Yash Kushwah, Aman Sharma, Dhananjay R. Mishra〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Experimental and theoretical evaluation of conventional solar still (CSS) and CSS augmented with permanent ferrite ring magnets (MSS) have been reported. Mathematical model proposed by Kumar & Tiwari has been used for the evaluation of internal heat transfer coefficients, internal efficiency, exergy efficiency, and exergy destruction. The average partial pressure difference between basin water and inner condensing cover surface for MSS has been found to be 77.99% higher than CSS when experiments were carried out for 13 h. The maximum value of evaporative heat transfer coefficient of MSS leads over the CSS by 28.65% at 13:00 h. The distillate yield recorded during the experimentation for MSS is 49.22% higher as compared to CSS. It seems that the magnetization of water has enhanced the overall internal efficiency and exergy efficiency of MSS over CSS by 49.17% and 110.26% respectively. In MSS the presence of permanent magnets has remarkably reduced the exergy destruction in the basin area. Augmentation of magnets with the CSS has significantly enhanced the distillate output of MSS. It has been found that the theoretical results obtained from Kumar & Tiwari numerical model are in good agreement with the experimental results obtained from CSS and MSS.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 459〈/p〉 〈p〉Author(s): Ning Liu, Zhongliang Liu, Yanxia Li, Lixia Sang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Leakage in isobaric energy recovery devices (ERDs) is inevitable. Three seal structures are introduced and studied for a fully-rotary valve energy recovery device (FRV-ERD) to reduce leakage. Effects of pressure difference and geometrical parameters of seal structure on leakage are investigated and compared for different seal structures. Results show that, as the key component of this ERD, the fully-rotary valve (FRV) achieves its best seal performance with the bilateral seal. For the FRV-ERD of design parameters, both the efficiency and required clearance are improved by using the bilateral seal to replace the original seal. The calculated efficiency is improved from 89.48% to 92.05% at the clearance of 30 μm under operating pressure and the required clearance increases from 18.1 μm to 20.4 μm. Based on the results of the optimized bilateral seal, an approximate leakage rate equation is proposed and can be used for design calculation. The performance of FRV-ERD with the optimized bilateral seal is improved greatly. Compared with FRV-ERD with the original seal, the efficiency of FRV-ERD with the optimized bilateral seal is improved from 89.48% to 96.33% at the clearance of 30 μm under operating pressure, and the required clearance increases from 18.1 μm to 29.5 μm, easing machining difficulty greatly.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 459〈/p〉 〈p〉Author(s): Muhammad Qasim, Mohamed Badrelzaman, Noora N. Darwish, Naif A. Darwish, Nidal Hilal〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Water scarcity is a grand challenge that has always stimulated research interests in finding effective means for pure water production. In this context, reverse osmosis (RO) is considered the leading and the most optimized membrane-based desalination process that is currently dominating the desalination market. In this review, various aspects of RO desalination are reviewed. Theories and models related to concentration polarization and membrane transport, as well as merits and drawbacks of these models in predicting polarization effects, are discussed. An updated review of studies related to membrane modules (plate and frame, tubular, spiral wound, and hollow fiber) and membrane characterization are provided. The review also discusses membrane cleaning and different pre-treatment technologies in place for RO desalination, such as feed-water pre-treatment and biocides. RO pre-treatment technologies, which include conventional (e.g., coagulation-flocculation, media filtration, disinfection, scale inhibition) and non-conventional (e.g., MF, UF, and NF) are reviewed and their relative attributes are compared. As per the available literature, UF, MF and coagulation-flocculation are considered the most widely used pre-treatment technologies. In addition, this review discusses membrane fouling, which represents a serious challenge in RO processes due to its significant contribution to energy requirements and process economy (e.g., flux decline, permeate quality, membrane lifespan, increased feed pressure, increased pre-treatment and membrane maintenance cost). Different membrane fouling types, such as colloidal, organic, inorganic, and biological fouling, are addressed in this review. Principles of RO process design and the embedded economic and energy considerations are discussed. In general, cost of water desalination has dropped to values that made it a viable option, comparable even to conventional water treatment methods. Finally, an overview of hybrid RO desalination processes and the current challenges faced by RO desalination processes are presented and discussed.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 460〈/p〉 〈p〉Author(s): Yunlong Qian, Xiaoling Zhang, Chuanyao Liu, Chen Zhou, Aisheng Huang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A series of aliphatic terminal diamines with different kinetic diameter length, including 1,2-diaminoethane (A2), 1,3-diaminopropane (A3), 1,4-diaminobutane (A4), 1,5-diaminopentane (A5), 1,6-diaminlhexane (A6), 1,7-diaminoheptane (A7), and 1,8-diaminooctane (A8), were selected as built-in molecules of graphene oxide (GO) to fabricate diamine modified graphene oxide nanosheets (Ax-GO). Through vacuum filtration method, diamine modified Ax-GO membranes with tunable interlayer spacing were deposited on the polydopamine (PDA) modified α-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 supports. The separation performances of the Ax-GO membranes were evaluated for seawater desalination by pervaporation. It is found that the water fluxes of the Ax-GO membranes increase with the enhancement of the interlayer spacing of the Ax-GO. Impressively, A4-GO membrane displays the best performance with water flux of 19.7 kg·m〈sup〉−2〈/sup〉·h〈sup〉−1〈/sup〉 and ion rejection of 99.9% at 90 °C for desalination of 3.5 wt% seawater. Further, A4-GO membrane shows high stability for seawater desalination, and the desalination performance keeps unchanged up to 168 h at 75 °C.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418323579-ga1.jpg" width="385" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 467〈/p〉 〈p〉Author(s): Hilla Shemer, Raphael Semiat, David Hasson〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The corrosive tendency of desalinated water is commonly controlled by dosing acid to water flowing through a packed bed of limestone as to make it slightly supersaturated with respect to calcium carbonate. Acidification is achieved by dosage of either carbonic acid or sulfuric acid. Design models for re-mineralization in packed bed contactors are well established. Reduction of the carbon dioxide consumption required for re-mineralization, may be achieved by partial replacement with sulfuric acid, while maintaining the regulation stipulating a ratio of 1.3 to 2.0 between the equivalent alkalinity and calcium concentrations. The objective of this work was to extend the established kinetic model based on a single acid dissolution to the case of dissolution by a mixture of carbon dioxide and sulfuric acid. The derived model predicts the molar ratio of bicarbonate to calcium, in the product water, as a function of the molar ratio between the two acids. Experimental and predicted dissolution profiles are shown to be in very good agreement.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 462〈/p〉 〈p〉Author(s): Jie Zhou, Yue Wang, Zhongming Feng, Zhisong He, Shichang Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Reciprocating-switcher energy recovery device (RS-ERD) can reduce the energy consumption in membrane desalination system for its high efficiency. However, the initial one-plate structure of the RS-ERD requires a large diameter in plates to ensure its basic capacity, which not only enlarges the switching load of water hydraulic actuator, but also causes a significant fluid fluctuation of the device during the stroke switching. To solve the problem, a modified RS-ERD with the pilot valve plates was designed and experimentally investigated in a SWRO desalination system. The experimental results illustrated that compared to the previous RS-ERD, the starting-up pressure for the new RS-ERD decreased by a half to be about 0.25 MPa, and 72.16% HP brine consumption for water hydraulic actuator was reduced in stroke switching. Thanks to the significant decrease in HP brine consumption, the pressure fluctuation amplitude in HP fluids was declined by 40% under the pressure of 6.00 MPa and the flow rate of 30 m〈sup〉3〈/sup〉/h. Meantime the new RS-ERD remains a competitive energy recovery efficiency of up to 98.50%. This paper provides a practical method to improve the working performance of RS-ERD.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 461〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 462〈/p〉 〈p〉Author(s): Hui Kou, Zixiao Liu, Bo Zhu, Daniel K. Macharia, Sharjeel Ahmed, Binhe Wu, Meifang Zhu, Xiaogang Liu, Zhigang Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Photothermal membranes have shown tremendous potential for solar-driven seawater desalination, but their practical applications are hindered by the relatively high cost and solid salt separation. To overcome these limitations, we have developed low-cost and washable photothermal fabrics by dyeing traditional cotton fabrics with carbon nanotube (CNT)-based ink. CNT dyed cotton (cotton-CNT) fabrics exhibit strong optical absorption in 250–2500 nm with a total solar absorption efficiency of 95.7%. Using a polystyrene (PS) foam as the thermal insulator, cotton-CNT fabrics exhibit a high seawater evaporation rate of 1.59 Kg m〈sup〉−2〈/sup〉 h〈sup〉−1〈/sup〉 under simulated sunlight (1.0 KW m〈sup〉−2〈/sup〉). More importantly, the fabric can be cleaned and recycled by removing the salts formed after evaporation, through a simple hand-washing process. These cotton-CNT fabrics may provide a new platform for low-cost, high-efficient and large-area seawater desalination under sunlight irradiation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Inspired by clothes, CNT-dyed cotton fabrics have been prepared, and they exhibit excellent hydrophilicity, flexibility and high seawater evaporation rate of 1.59 Kg m〈sup〉−2〈/sup〉 h〈sup〉−1〈/sup〉 under the simulated sunlight (1.0 KW m〈sup〉−2〈/sup〉). Importantly, the separated solid salt on fabric can be easily cleaned by a simple hand-washing process, and thus the fabric gets recovered with high stability.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001191641832530X-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 462〈/p〉 〈p〉Author(s): Hadi Rostamzadeh, Amin Shekari Namin, Pejman Nourani, Majid Amidpour, Hadi Ghaebi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Water distillation via solar energy is investigated potentially as an appreciable topic across the globe in recent decades. While many high-efficient solar collectors are developed for this objective, it is discovered that solar pond with big size can be more cost-effective than many types of high-efficient collectors. In pursuance of this objective, plausibility of extracting thermal heat from a salinity-gradient solar pond (SGSP) set-up for water distillation via a humidification-dehumidification (HDH) system is scrutinized under privilege of thermodynamics laws. Furthermore, due to the fact that solar pond's pumps consume more power for their task, two thermoelectric generators (TGEs) are posited to use waste heat of the discarded brine and distilled water to generate electricity for power demands. Single-criterion optimization is executed for the suggested set-up and the results are presented for the Urmia lake in Iran. Considering maximization of distilled water scenario, the findings outlined that 4.5 m〈sup〉3〈/sup〉/h distilled water and 3.16 kW net electricity can be generated with cogeneration Gain-Output-Ratio (CGOR) of 1.56 and exergy-based CGOR (ECGOR) of 4.87%. Also, the designed desalination unit generated more fresh water between 22 May and 22 July for Urmia province, while more electricity is generated between 21 April and 21 May. Among all constituents of the introduced SGSP/HDH system, dehumidifier attributed as the major site of loss by exergy destruction of 15.23 kW. At last, an exhaustive parametric evaluation is established to scrutinize impact of some preeminent design parameters on the targets. It is exhibited that the CGOR can be maximized with desalination flow ratio, while the ECGOR can be maximized with lower-convective zone temperature.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 461〈/p〉 〈p〉Author(s): Naef A.A. Qasem, Syed M. Zubair〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper introduces a novel humidification-dehumidification (HDH) system coupled with adsorption desalination (AD) system to produce freshwater as well as to obtain chilled water for an air-conditioning purpose. Two hybrid HDH-AD schemes are proposed in which the condenser of the AD system replaces the HDH heater. The difference is that the HDH inlet seawater is precooled in the AD evaporator before feeding the HDH system in Scheme # 1, while in Scheme # 2 the seawater is used to cool the adsorption process. Seawater mass flowrate and temperature, heating source mass flowrate and temperature, cycling time, and HDH mass flowrate ratio are the key parameters investigated to influence the hybrid system performance. The results exhibit that the gained output ratio (GOR) and cost values are higher in Scheme #1 (about 7.8 and 0.64 ¢/Liter, respectively). Scheme # 2 achieves an excellent GOR and cost values (about 7.6 and 0.65 ¢/Liter) with a cooling effect as a by-product (coefficient of performance (COP) is 〉0.45 under the same conditions of optimal GOR value). For the hybrid HDH-AD system, the HDH contribution in the total performance is vital while AD system can be used to control the HDH operating conditions.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 463〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 464〈/p〉 〈p〉Author(s): Shuya Li, Baoyu Gao, Yang Wang, Bo Jin, Qinyan Yue, Zhining Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The development of thin film nanocomposite (TFN) reverse osmosis (RO) membranes has promoted the membrane technology for desalination. Novel nanocomposites are urgently being explored to develop superior performance TFN RO membranes. Graphene oxide quantum dots (GOQD) is considered to be an ideal nanofiller for improving membrane permeability due to its rich hydrophilic groups, uniform dispersion and small nanosheet shape. As a silver ion (Ag〈sup〉+〈/sup〉) compound, silver phosphate (AP) possesses higher bactericidal effect than silver particle in membrane application. Accordingly, we synthesized the multifunctional nanocomposite of AP loaded GOQD by a facile electrostatically driven method. Subsequently, GOQD/AP was embedded into the dense polyamide (PA) layer via interfacial polymerization reaction. The GOQD/AP incorporated TFN membrane possessed a high flux of 39.6 L·m〈sup〉−2〈/sup〉·h〈sup〉−1〈/sup〉 at 16 bar, which was 1.5-fold higher than that of the pristine TFC membrane. Meanwhile, the salt rejection was maintained at 98.4%. Noteworthy, the TFN-GOQD/AP membrane exhibited strong bactericidal property against 〈em〉E. coli〈/em〉 with a sterilization rate of 99.9% and good stability as well as excellent antifouling performance during RO process. This work provides a feasible strategy to prepare high permselective and anti-bacterial TFN RO membranes for desalination and wastewater reclamation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001191641832592X-ga1.jpg" width="315" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 467〈/p〉 〈p〉Author(s): Seong-Yong Woo, Ho-Saeng Lee, Ho Ji, Deok-Soo Moon, Young-Deuk Kim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, a prototype of an adsorption desalination (AD) system was designed and manufactured using commercially available alumina silica gel to evaluate and improve its performance. To develop the AD system, the thermophysical properties of the adsorbent were first investigated based on adsorption isotherms of nitrogen and water vapor on the adsorbent; thereby, its applicability as a candidate adsorbent was verified. The performance of the AD system was then evaluated for different types of brine feeders in the evaporator (i.e., perforated plate and spray nozzles) using tap water as a feed over a wide range of key operating conditions such as hot-, cooling-, and chilled-water temperatures. Moreover, the performance of the AD process was assessed to verify the desalination mechanism and consistent desalting performance of the AD process; the process recovered more freshwater from seawater than conventional desalination technologies. The performance of the AD system was demonstrated to be independent of the brine concentration of the evaporator; moreover, the chemical quality of the freshwater recovered was revealed to be comparable to that of deionized water. Spray-assisted evaporation exhibited high water vapor uptake owing to the effect of pressurization during the adsorption process, and hence, exhibited remarkable performance.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 467〈/p〉 〈p〉Author(s): Ye Li, Saren Qi, Miao Tian, Wentalia Widjajanti, Rong Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study focuses on enhancing the mechanical strength of aquaporin (AQP)-based biomimetic membranes for seawater desalination. AQP incorporated vesicles were embedded into the selective layer of an optimized thin film composite (TFC) membrane. The resultant membrane, denoted as ASW, exhibited a stable water flux around 20 L·m〈sup〉−2〈/sup〉·h〈sup〉−1〈/sup〉 and 99% NaCl rejection at a constant pressure of 55 bar using 32,000 mg·L〈sup〉−1〈/sup〉 NaCl solution as feed in reverse osmosis (RO) measurement. The robustness of the ASW membranes were evaluated. The water flux of ASW membrane was almost 100% enhanced compared with that of AQP-free control TFC membranes. The filtration performance of the ASW membrane was further evaluated by a seven-day desalination test using a real seawater secondary effluent collected from a desalination plant in Singapore as feed. To our best knowledge, our study is the first report on the AQP-incorporated RO membrane applied for seawater desalination. A commercial SW30HR membrane was tested in parallel for comparison. The robust ASW membrane exhibited a nearly 80% higher water flux in comparison to the SW30HR membrane with a comparable overall solute rejection, suggesting the advantage and feasibility of Aquaporin based biomimetic membranes for seawater desalination.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 461〈/p〉 〈p〉Author(s): Mohan Qin, Akshay Deshmukh, Razi Epsztein, Sohum K. Patel, Oluwaseye M. Owoseni, W. Shane Walker, Menachem Elimelech〈/p〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 464〈/p〉 〈p〉Author(s): Myoung Jun Park, Sungil Lim, Ralph Rolly Gonzales, Sherub Phuntsho, Dong Suk Han, Ahmed Abdel-Wahab, Samer Adham, Ho Kyong Shon〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study focused on the development of pressure retarded osmosis (PRO) thin film composite (TFC) membranes for enhanced osmotic power using hollow fiber polyethersulfone (PES) support structure modified by incorporating hydrophilic graphene oxide (GO) nanosheets. The GO loadings in the hollow fiber substrates were varied to improve water flux performances without compromising the mechanical strength. GO embedded (≤0.2 wt%) PES hollow fiber supports revealed noticeable improvements in pure water permeability, improved structural morphologies, as well as the hydrophilicity within the support layer, without deteriorating the mechanical properties. The GO (0.2 wt%)-incorporated TFC-PRO membrane appeared to have an initial PRO flux (without any applied pressure) of 43.74 L m〈sup〉−2〈/sup〉 h〈sup〉−1〈/sup〉, lower specific reverse salt flux of 0.04 g L〈sup〉−1〈/sup〉 and structural parameter (〈em〉S〈/em〉) of 522 μm, significantly better than the control membrane. The maximum power density of 14.6 W m〈sup〉−2〈/sup〉 was achieved at an operating pressure of 16.5 bar under the condition of DI water and 1 M NaCl as feed and draw solutions, respectively. The results obtained in this study indicate that modification of PRO hollow fiber support layer by incorporating nanoparticles such as GO nanosheet can be a useful tool to improve the PRO performance.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418325396-ga1.jpg" width="336" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 464〈/p〉 〈p〉Author(s): Mengjuan Mi, Xiaojun Liu, Weiqing Kong, Yongjie Ge, Weiqi Dang, Jiawen Hu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Capacitive deionization (CDI) is a promising technique for water treatment and desalination. To enable high CDI performance, the electrode materials should possess high surface area, conductivity, hydrophilicity, and cycling stability. Here, we report the design and construction of a hierarchical porous composite of N-doped hollow mesoporous carbon sphere and holey graphene hydrogel with in-plane pores, 〈em〉i.e.〈/em〉, N-HMCS/HGH composite, for high-performance CDI. The N-HMCS/HGH composite shows a three-dimensional (3D), hierarchical porous structure with a specific surface area of 337.7 m〈sup〉2〈/sup〉 g〈sup〉−1〈/sup〉, high conductivity, and high hydrophilicity. With these structural characteristics, the optimized N-HMCS/HGH electrode exhibits a large specific capacitance (226.5 F g〈sup〉−1〈/sup〉) in 0.5 M NaCl solution to ensure a large electrosorption capacity of 17.8 and 32 mg g〈sup〉−1〈/sup〉 in a feeding NaCl solution with initial concentration of 500 and 2500 mg L〈sup〉−1〈/sup〉, respectively. Upon 35 CDI-regeneration cycles, the electrosorption capacity of the N-HMCS/HGH electrode shows no obvious attenuation, exhibiting excellent cycling stability. These results indicate that the hierarchical N-HMCS/HGH composite shows great potential for practical application.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0011916418323294-ga1.jpg" width="472" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 464〈/p〉 〈p〉Author(s): Hong Wu, Haoyu Yin, Yulong Li, Xianghua Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Mechanical vapor recompression (MVR) technology has broad prospects for application in saving energy. The compression in the MVR system often involves mixing vapor and liquid, and therefore, studies of the process can help establish a theoretical model to solve the problem of controlling compression temperature and improving the compression process's efficiency. However, the mixed phase-change in water vapor compression is complex and differs from that in air wet compression. In this paper, we studied droplets' effect on water vapor compression performance and the mechanism of heat and mass transfer during the process. A 2D single droplet evaporation model for water vapor compression was established and analyzed with Python, and a 3D numerical simulation was solved with CFD software to investigate the effect on water vapor compression of droplet diameter, ambient pressure and temperature, spray flow rate, and flow velocity. The results showed that the compressor's outlet temperature can be reduced by reducing the droplet diameter and increasing the spray flow rate, thus decreasing the work required for compression. The results also indicated that a high pressure ratio and superheat can enhance the cooling effect greatly.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Desalination, Volume 464〈/p〉 〈p〉Author(s): Shasha An, Jie Liu, Jihong Wang, Huajing Zhu, Zhiyong Ji, Tao Zhang, Yingying Zhao, Junsheng Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Currently, it is commonly observed that ion flux decreases as the separation performance of cation exchange membranes between mono- and double-charged ions improves. Therefore, cation exchange membranes with simultaneously excellent separation performance and high ionic flux must be developed. Herein, a series of pure and organic-inorganic cross-linked membranes were synthesized using UV irradiation. The synthetic membranes showed high ion-exchange capacity (IEC) and large ion flux. The organic-inorganic membranes achieved excellent mechanical properties, thermal stability, and separation properties owing to the addition of SiO〈sub〉2〈/sub〉. When the silica content was 4 wt%, the three ionic perm-selectivity showed their highest separation performances of 1.70 ± 0.03(〈em〉P〈/em〉〈sub〉〈em〉K〈/em〉〈/sub〉〈sup〉〈em〉Na〈/em〉〈/sup〉), 5.84 ± 0.04(〈em〉P〈/em〉〈sub〉〈em〉K〈/em〉〈/sub〉〈sup〉〈em〉Mg〈/em〉〈/sup〉), and 25.67 ± 0.04 (〈em〉P〈/em〉〈sub〉〈em〉K〈/em〉〈/sub〉〈sup〉〈em〉Ca〈/em〉〈/sup〉), representing an increase of 70% (〈em〉P〈/em〉〈sub〉〈em〉K〈/em〉〈/sub〉〈sup〉〈em〉Na〈/em〉〈/sup〉), 279.22% (〈em〉P〈/em〉〈sub〉〈em〉K〈/em〉〈/sub〉〈sup〉〈em〉Mg〈/em〉〈/sup〉), and 1236.98% (〈em〉P〈/em〉〈sub〉〈em〉K〈/em〉〈/sub〉〈sup〉〈em〉Ca〈/em〉〈/sup〉) compared than those of pure membrane. In addition, the limiting current density of the prepared organic-inorganic membranes was all 〉8.74 mA/cm〈sup〉2〈/sup〉, higher than that of commercial membrane. According to these excellent performances, the prepared membranes showed good prospects for separation performance of cation exchange membranes. The addition of a proper amount of inorganic particles can improve the ion perm-selectivity between mono- and double-charged ions.〈/p〉〈/div〉 〈/div〉