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Kuglarz, Mariusz, Klaudiusz Grübel, and Jolanta Bohdziewicz. "Post-Digestion Liquor Treatment in the Method Combining Chemical Precipitation with Reverse Osmosis." Archives of Environmental Protection 40, no. 3 (December 11, 2014): 29–42. http://dx.doi.org/10.2478/aep-2014-0030.
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Abstract The aim of the study was to develop an effective treatment of post-digestion liquors highly-loaded with biogenic and organic substances. The scope of the research project encompassed: mesophilic anaerobic digestion of waste activated sludge (WAS) as well as the treatment of post-digestion liquors, coming from the most appropriate HRT value of 25 days, in the process of ammonium magnesium phosphate (struvite) precipitation targeted at ammonia nitrogen binding and a subsequent reverse osmosis (RO) process. It was established that the method combining chemical precipitation and high-pressure filtration ensures a high degree of contaminants removal allowing for a direct release of treated liquors into the natural reservoir. However, in order to decrease the residual NH4+ concentration (6.1 mg NH4+/dm3) in the purified post-digestion liquors below the level allowing for a direct release to the natural reservoir, it turned out to be necessary to apply increased molar ratio of magnesium and phosphates (Mg:NH4+: PO43-= 1.5:1:1.5).
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Baumgarten, G., and C. F. Seyfried. "Experiences and new developments in biological pretreatment and physical post-treatment of landfill leachate." Water Science and Technology 34, no. 7-8 (October 1, 1996): 445–53. http://dx.doi.org/10.2166/wst.1996.0653.
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The leachate treatment plant of the landfill in Mechernich including biological pretreatment, reverse osmosis and evaporation and drying of the concentrate has been in operation since the beginning of 1994. Originally the plant was designed for a capacity of 130 m3/d. In the future, an average leachate amount of ca. 280 m3/d and even considerably higher montly peaks must be assumed. The necessary enlargement of the biological pretreatment will be realized by a second biological contactor plant. Corresponding to the operation of the existing plant a large amount of the ammonium can be eliminated under aerobic conditions by deammonification so no enlargement of the denitrification stage is needed. by simply replacing the reverse osmosis membranes by nanofiltration membranes, an operational capacity of ca. 280 m3/d may easily be achieved at the existing physical post-treatment stage. With the aid of this enlargement conception, the relatively high operational costs at present will be reduced considerably.
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Pham, Duc-Truc, Vanessa J. Stockdale, David Wollan, David W. Jeffery, and Kerry L. Wilkinson. "Compositional Consequences of Partial Dealcoholization of Red Wine by Reverse Osmosis-Evaporative Perstraction." Molecules 24, no. 7 (April 10, 2019): 1404. http://dx.doi.org/10.3390/molecules24071404.
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This study investigated compositional changes in red wines resulting from wine alcohol removal by reverse osmosis-vaporative perstraction (RO-EP) and provides insight into the physical and chemical changes in reduced alcohol wine (RAW). Trial 1 involved RO-EP treatment of three wines that were analyzed pre-treatment, post-treatment, and post-treatment with alcohol adjustment (i.e., addition of ethanol to achieve the original alcohol content). Trial 2 involved partial dealcoholization of two wines and analysis of samples collected during RO-EP treatment, i.e., wine in, wine out, retentate, permeate (pre- and post-EP treatment) and strip water. Wine color was analyzed by spectrophotometric methods, while other compositional changes were determined by WineScan, high performance liquid chromatography (HPLC) and gas chromatography–mass spectrometry (GC–MS) analyses. In general, RAWs were slightly more concentrated than pre-treatment wines, which resulted in greater color intensity and increased phenolics and organic acids. However, partial dealcoholization resulted in lower concentrations of some fermentation volatiles, particularly ethyl esters, which may reflect ester hydrolysis following ethanol removal.
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Bohdziewicz, Jolanta, and Mariusz Kuglarz. "Treatment of post-digestion liquors with the application of struvite precipitation and reverse osmosis." Desalination and Water Treatment 51, no. 1-3 (August 20, 2012): 366–73. http://dx.doi.org/10.1080/19443994.2012.715074.
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Al-Awadi, F., and M. Abdel-Jawad. "Evaluation of the three post-treatment systems at Doha seawater reverse osmosis plant — Kuwait." Desalination 63 (January 1987): 109–17. http://dx.doi.org/10.1016/0011-9164(87)90044-0.
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Slim, J. A., D. G. Devey, and J. W. Vail. "The Feasibility of Tubular Reverse Osmosis for Water Reclamation on a Large Scale." Water Science and Technology 25, no. 10 (May 1, 1992): 299–318. http://dx.doi.org/10.2166/wst.1992.0257.
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The City of Port Elizabeth designed its main sewage treatment works with water reclamation in mind and, as the reverse osmosis process, in earlier pilot plant investigations, had shown promise in its ability to produce potable water from a sewage works tertiary effluent, a full scale tubular reverse osmosis (RO) plant was installed and operated for about 12 000 hours. The investigation showed that, although renovated water of high quality can consistently be produced under normal sewage treatment plant operating conditions, using existing plant operating personnel, frequent mechanical and instrument failures indicated the need for more reliable equipment. Feed flow to the plant averaged 25 475 1/hr with a product recovery rate of 67.5%. A 13% reduction in peak standard flux occurred, indicating that membrane fouling could be controlled within acceptable limits even though the feed received no pre-treatment other than rapid sand filtration and chlorination. No abnormal degradation of the membrane was indicated. The results obtained indicated that chemically the product was of good potable quality with the possible exception of the levels of ammoniacal nitrogen, phenols and organic pollution indicators. Bacteriological quality of the product was not satisfactory but this could easily be rectified by the provision of adequate post disinfection. Daphnia pulex toxicity tests indicated that the RO product was on occasion undesirable for human consumption. The total cost of the RO product was R l.86/kl. Although the tubular RO process has great potential for producing potable water from a tertiary sewage effluent without pre-treatment, a further stage of post-treatment is probably necessary to remove micro-pollutants.
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Wohlmuth da Silva, Salatiel, Carla Venzke, Júlia Bitencourt Welter, Daniela Schneider, Jane Zoppas Ferreira, Marco Siqueira Rodrigues, and Andréa Moura Bernardes. "Electrooxidation Using Nb/BDD as Post-Treatment of a Reverse Osmosis Concentrate in the Petrochemical Industry." International Journal of Environmental Research and Public Health 16, no. 5 (March 6, 2019): 816. http://dx.doi.org/10.3390/ijerph16050816.
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This work evaluated the performance of an electrochemical oxidation process (EOP), using boron-doped diamond on niobium substrate (Nb/BDD), for the treatment of a reverse osmosis concentrate (ROC) produced from a petrochemical wastewater. The effects of applied current density (5, 10, or 20 mA·cm−2) and oxidation time (0 to 5 h) were evaluated following changes in chemical oxygen demand (COD) and total organic carbon (TOC). Current efficiency and specific energy consumption were also evaluated. Besides, the organic byproducts generated by EOP were analyzed by gas chromatography coupled to mass spectrometry (GC–MS). The results show that current densities and oxidation time lead to a COD and TOC reduction. For the 20 mA·cm−2, changes in the kinetic regime were found at 3 h and associated to the oxidation of inorganic ions by chlorinated species. After 3 h, the oxidants act in the organic oxidation, leading to a TOC removal of 71%. Although, due to the evolution of parallel reactions (O2, H2O2, and O3), the specific energy consumption also increased, the resulting consumption value of 66.5 kW·h·kg−1 of COD is considered a low energy requirement representing lower treatment costs. These results encourage the applicability of EOP equipped with Nb/BDD as a treatment process for the ROC.
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Bloetscher, Frederick, David Stambaugh, James Hart, Jon Cooper, Karl Kennedy, Lauren Sher, Anthony P. Ruffini, Augustus Cicala, and Samantha Cimenello. "Use of lime, limestone and kiln dust to stabilize reverse osmosis treated water." Journal of Water Reuse and Desalination 3, no. 3 (February 27, 2013): 277–90. http://dx.doi.org/10.2166/wrd.2013.093.
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The City of Pembroke Pines is embarking on an alternative water supply (AWS) project that includes the potential of using treated wastewater for aquifer recharge. The concept includes the use of reverse osmosis membranes, ultraviolet disinfection and advanced oxidation processes downstream of activated sludge and microfiltration. One of the problems is that the permeate leaves the process grossly under-saturated, because with respect to minerals, virtually everything in the water is removed by the reverse osmosis membranes. The practical natural minimum hardness level for water is 40 mg L−1 as CaCO3, while the permeate water was <7 mg L−1. As a result, a post-treatment system needed to be designed to restore minerals to the water to achieve stability so the water does not dissolve metals, other piping and treatment tank materials. Traditionally reverse osmosis plants for potable water systems use caustic soda, polyphosphates, orthophosphates and other chemicals to address the stability issue. These are costly and for an aquifer recharge project, the costs seemed high. For this project, the research focused on alternative solutions to restore hardness, alkalinity and pH using lime, limestone and kiln dust. All three resolved the pH and stability issues for the pilot process.
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Lee, Chulmin, Yesol Kang, Dong-Ho Kim, and In S. Kim. "Practical Considerations of Wastewater–Seawater Integrated Reverse Osmosis: Design Constraint by Boron Removal." Membranes 11, no. 4 (March 28, 2021): 240. http://dx.doi.org/10.3390/membranes11040240.
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The wastewater–seawater (WW-SW) integrated reverse osmosis (RO) process has gained much attention in and out of academia due to its energy saving capability, economic benefits, and sustainability. The other advantage of this process is to reduce boron concentration in the RO permeate that can exclude the post-treatment process. However, there are multiple design constraints regarding boron removal that restrict process design in the WW-SW integrated system. In this study, uncertainties in design factors of the WW-SW integrated system in consideration of boron removal have been explored. In comprehensive consideration of the blending ratio of between WW and SW, regulatory water quality standard, specific energy consumption (SEC), specific water cost, and RO recovery rate, a range of 15,000~20,000 mg/L feed turned out to be the most appropriate. Furthermore, boron rejection tests with SWRO (seawater reverse osmosis) and BWRO (brackish water reverse osmosis) membranes under actual WW-SW integration found a critical reduction in boron rejection at less than 20 bar of operating pressure. These findings emphasize the importance of caution in the use of BWRO membranes in the WW-SW integrated RO system.
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Myung, S. W., I. H. Choi, S. H. Lee, I. C. Kim, and K. H. Lee. "Use of fouling resistant nanofiltration and reverse osmosis membranes for dyeing wastewater effluent treatment." Water Science and Technology 51, no. 6-7 (March 1, 2005): 159–64. http://dx.doi.org/10.2166/wst.2005.0634.
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Dyeing wastewater was post-treated by using nanofiltration (NF) and reverse osmosis (RO) membranes. To reduce membrane fouling, poly (vinyl alcohol) (PVA) with a neutral charge was coated on NF and RO membranes. The effect of surface charge and surface roughness on membrane fouling was investigated. Dyeing wastewater was pre-treated by using coagulation, activated sludge process, and MF process to investigate the effect of the pre-treatment on the membrane fouling. It is demonstrated that the extent of fouling is significantly influenced by the surface roughness and the surface charge on the NF and RO membranes. A membrane with a smooth and neutral surface was fouled less. The pre-treatment was essential for avoiding NF and RO membranes fouling. The quality of the final permeate was acceptable for water reuse.
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Abuatayef, Mazen, Abedelmajeed Kahail, Hassan Al-Najjar, and Thaer AbuShbak. "APPLICABILITY OF USING REVERSE OSMOSIS MEMBRANE TECHNOLOGY FOR WASTEWATER RECLAMATION IN THE GAZA STRIP." Journal of Engineering Research [TJER] 17, no. 1 (May 22, 2020): 11. http://dx.doi.org/10.24200/tjer.vol17iss1pp11-23.
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Reverse osmosis (RO) technology shows common popularity in the field of water treatment as an advanced stage to eliminate the residual biogenic elements and dissolved impurities after the traditional treatment processes. This article highlights the applicability of using RO membrane technology as a post-treatment stage to treat the discharged effluent from the Gaza wastewater treatment plant. The designed experimental model reveals optimal removal efficiency between 92 and 100% for a number of physical, chemical and biological pollutants. The RO membrane unit demonstrates significant removal efficiency compared to the sand filter where the RO removal efficiency for BOD, TSS, TDS, Fecal Coliform and NO3 were 100, 97.5, 92, 100 and 100%, respectively. The quality of reclaimed wastewater was idealistic where the contents of BOD, Fecal Coliform and NO3 in the permeate were nil, and the concentrations of TDS and TSS were 20 and 296 ppm, respectively. Practically, the results confirm that the wastewater with the reclaimed quality could be used for agricultural activities with no degree of restriction according to FAO’s guidelines water quality for irrigation. According to the Palestinian Standard (PS), the quality of reclaimed wastewater is high, class (A), and it could be used without restrictions to irrigate many crops and for the purposes of groundwater replenishment. Related to energy estimation and cost analysis, the numerical model and the market analysis study demonstrate the energy of 1.23 kWh and total cost, i.e. fixed and energy costs, of 0.58 USD to produce 1 m3 of reclaimed wastewater using the RO membrane in the Gaza Strip over a projected lifespan of 5 years.
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Rozzi, A., F. Malpei, R. Bianchi, and D. Mattioli. "Pilot-scale membrane bioreactor and reverse osmosis studies for direct reuse of secondary textile effluents." Water Science and Technology 41, no. 10-11 (May 1, 2000): 189–95. http://dx.doi.org/10.2166/wst.2000.0640.
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Post-treatment of secondary wastewater (80% textile, 20% municipal) was tested on a pilot scale low-pressure reverse osmosis (RO) module, to produce a polished effluent to be recycled into the textile factories. Two different flow sheets were used. In the first one, the feed to the RO was pre-treated in a coagulation and filtration unit. In the second one, a ZenoGem® membrrane hollow fibre reactor was used to separate the activated sludge from the permeate which was fed to the RO module. Experimental results are discussed as well as advantages and disadvantages of the two alternatives.
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Bick, Amos, and Gideon Oron. "Post-treatment design of seawater reverse osmosis plants: boron removal technology selection for potable water production and environmental control." Desalination 178, no. 1-3 (July 2005): 233–46. http://dx.doi.org/10.1016/j.desal.2005.01.001.
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Mielczarek, Karolina, Jolanta Bohdziewicz, Maria Włodarczyk-Makuła, and Marzena Smol. "Comparison of post-process coke wastewater treatment effectiveness in integrated and hybrid systems that combine coagulation, ultrafiltration, and reverse osmosis." Desalination and Water Treatment 52, no. 19-21 (February 21, 2014): 3879–88. http://dx.doi.org/10.1080/19443994.2014.887500.
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Lopes, Thiago Santos de Almeida, Rainer Heßler, Christoph Bohner, Gilson Barbosa Athayde Junior, and Rennio Felix de Sena. "Pesticides removal from industrial wastewater by a membrane bioreactor and post-treatment with either activated carbon, reverse osmosis or ozonation." Journal of Environmental Chemical Engineering 8, no. 6 (December 2020): 104538. http://dx.doi.org/10.1016/j.jece.2020.104538.
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Kaplan, Aviv, Hadas Mamane, Yaal Lester, and Dror Avisar. "Trace Organic Compound Removal from Wastewater Reverse-Osmosis Concentrate by Advanced Oxidation Processes with UV/O3/H2O2." Materials 13, no. 12 (June 19, 2020): 2785. http://dx.doi.org/10.3390/ma13122785.
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Advanced technologies, such as reverse osmosis (RO), allow the reuse of treated wastewater for direct or indirect potable use. However, even highly efficient RO systems produce ~10–15% highly contaminated concentrate as a byproduct. This wastewater RO concentrate (WWROC) is very rich in metal ions, nutrients, and hard-to-degrade trace organic compounds (TOrCs), such as pharmaceuticals, plasticizers, flame retardants, and detergents, which must be treated before disposal. WWROC could be up to 10 times more concentrated than secondary effluent. We examined the efficiency of several advanced oxidation processes (AOPs) on TOrC removal from a two-stage WWROC matrix in a pilot wastewater-treatment facility. WWROC ozonation or UV irradiation, with H2O2 addition, demonstrated efficient removal of TOrCs, varying between 21% and over 99% degradation, and indicating that radical oxidation (by HO·) is the dominant mechanism. However, AOPs are not sufficient to fully treat the WWROC, and thus, additional procedures are required to decrease metal ion and nutrient concentrations. Further biological treatment post-AOP is also highly important, to eliminate the degradable organic molecules obtained from the AOP.
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Samaei, Seyed Mohsen, Shirley Gato-Trinidad, and Ali Altaee. "Performance evaluation of reverse osmosis process in the post-treatment of mining wastewaters: Case study of Costerfield mining operations, Victoria, Australia." Journal of Water Process Engineering 34 (April 2020): 101116. http://dx.doi.org/10.1016/j.jwpe.2019.101116.
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Song, Zheng Zheng, Zhang Yong Wu, and Zi Yong Mo. "Transmission Performance of Water-Based Nano Fluid Based on Computational Fluid Dynamics." Advanced Materials Research 1095 (March 2015): 58–62. http://dx.doi.org/10.4028/www.scientific.net/amr.1095.58.
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The nanoboron carbide particle size is 60nm, dispersed in RO reverse osmosis membrane treatment water form water-based nanofluid by adding the dispersant. In experiment, Water-based nanoboron carbide fluid has good resistance sedimentation stability when adding sodium carboxymethyl cellulose as a dispersing agent. Prepared three kinds of water-based nanoboron carbide fluid, the mass fraction of nanoparticles is 0.6%, 0.8%, 1.0%. By establishing a model of U-shaped tube, simulated the water-based nanofluids flow field in U-shaped tube using FLUENT, get velocity flow lines picture and pressure variation graph by CFD post-processing. From simulation results obtained: Water-based nanoboron carbide has good transmission fluid performance when nanoparticles mass fraction of 0.8%.
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Siegrist, H., and A. Joss. "Review on the fate of organic micropollutants in wastewater treatment and water reuse with membranes." Water Science and Technology 66, no. 6 (September 1, 2012): 1369–76. http://dx.doi.org/10.2166/wst.2012.285.
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A brief review of the fate of micropollutants in membrane-based wastewater treatment due to sorption, stripping, biological degradation/transformation and membrane separation is discussed, to give an overview of these technologies due to the growing importance for water reuse purposes. Compared with conventional activated sludge treatment (CAS) micropollutant removal in membrane bioreactor (MBR) is slightly improved due to complete suspended solids removal and increased sludge age. For discharge to sensitive receiving waters advanced treatment, such as post-ozonation or activated carbon adsorption, is recommended. In water reuse plants nanofiltration (NF) and reverse osmosis (RO) efficiently reject micropollutants due to size exclusions as well as electrostatic and hydrophobic effects reaching potable quality. To remove micropollutants fully, additionally post-ozone or the addition of powdered activated carbon (PAC) have to be applied, which in parallel also reduce NDMA precursors. The concentrate has to be treated if disposed to sensitive receiving waters due to its high micropollutant concentration and ecotoxicity potential. The present review summarizes principles and capabilities for the most important membrane-based applications for wastewater treatment, i.e. porous membranes in MBRs (micro- or ultrafiltration) and dense membrane applications (NF and RO) for water reuse.
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Karabulut, Benan Yazici, and Ayse Dilek Atasoy. "Comparison of Electrocoagulation Process and Other Treatment Technologies in Fluoride Removal from Groundwater." Academic Perspective Procedia 2, no. 3 (November 22, 2019): 1275–82. http://dx.doi.org/10.33793/acperpro.02.03.142.
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Groundwater is one of the most important natural resources in the world and plays a very important role in the supply of drinking water. Fluoride is probably one of the most common groundwater pollutants in the world for various reasons (structure of soil and rocks, etc.). The concentration of fluoride in groundwater above 1.5 mg/L begins to pose some risks to human health. Various conventional techniques such as adsorption, ion exchange, reverse osmosis, nanofiltration, precipitation have been developed for the removal of fluoride from water. However, they have several limitations, such as post-treatment re-treatment, less efficiency and higher installation costs. The electrocoagulation process is an effective technology for fluoride removal within conventional techniques. In this study, fluoride removal technologies are emphasized, and the studies done in this field are examined. The aim of this study is to investigate the advantages of electrocoagulation method in fluoride removal and to compare electrocoagulation process with other treatment technologies.
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Rozzi, A., M. Antonelli, and M. Arcari. "Membrane Treatment of Secondary Textile Effluents for Direct Reuse." Water Science and Technology 40, no. 4-5 (August 1, 1999): 409–16. http://dx.doi.org/10.2166/wst.1999.0617.
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Post-treatment of secondary textile wastewater was tested at pilot scale on membrane modules (microfiltration MF, nanofiltration NF and reverse osmosis RO) for the direct reuse of polished effluent within the dyeing processes. The main polluting parameters monitored in the post-treatment were: organic compounds (COD), colour, surfactants and salinity (as conductivity). The first treatment scheme was made of ceramic MF followed by NF. Aluminium polychloride was added at high concentrations (of the order of 70 mg Al/L) to avoid MF membrane fouling. The quality of the final permeate, produced by NF fed on the MF permeate, was acceptable for water reuse. Clariflocculation (CF) plus multimedia filtration (MMF) followed by low-pressure RO was also tested. This process performed quite well: the RO module (p = 4 bar) ran for relatively long cycles (up to 80 hours) with 5% reduction of the permeate flow rate at a 10 L m−2 h−1 fluxes. A techno-economical analysis on the experimental data indicate that a high quality effluent (COD < 10 mg/l; conductivity < 40 μS/cm; negligible residual colour), to be recycled in the textile dyeing industry, may be produced at affordable costs (less than 0.25 ECU) from secondary textile wastewater.
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Han, Hongyi, Ruobin Dai, and Zhiwei Wang. "Fabrication of High-Performance Thin-Film Composite Nanofiltration Membrane by Dynamic Calcium-Carboxyl Intra-Bridging during Post-Treatment." Membranes 10, no. 7 (June 30, 2020): 137. http://dx.doi.org/10.3390/membranes10070137.
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Widespread applications of nanofiltration (NF) and reverse osmosis (RO)-based processes for water purification and desalination call for high-performance thin-film composite (TFC) membranes. In this work, a novel and facile modification method was proposed to fabricate high-performance thin-film composite nanofiltration membrane by introducing Ca2+ in the heat post-treatment. The introduction of Ca2+ induced in situ Ca2+-carboxyl intra-bridging, leading to the embedment of Ca2+ in the polyamide (PA) layer. This post modification enhanced the hydrophilicity and surface charge of NF membranes compared to the pristine membrane. More interestingly, the modified membrane had more nodules and exhibited rougher morphology. Such changes brought by the addition of Ca2+ enabled the significant increase of water permeability (increasing from 17.9 L·m−2·h−1·bar−1 to 29.8 L·m−2·h−1·bar−1) while maintaining a high selectivity (Na2SO4 rejection rate of 98.0%). Furthermore, the intra-bridging between calcium and carboxyl imparted the NF membranes with evident antifouling properties, exhibiting milder permeability decline of 4.2% (compared to 16.7% of NF-control) during filtration of sodium alginate solution. The results highlight the potential of using Ca2+-carboxyl intra-bridging post-treatment to fabricate high-performance TFC membranes for water purification and desalination.
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Liang, Juan, Anqi Deng, Rongjing Xie, Mylene Gomez, Jiangyong Hu, Jufang Zhang, Choon Nam Ong, and Avner Adin. "Impact of elevated Ca2+/Mg2+ concentrations of reverse osmosis membrane desalinated seawater on the stability of water pipe materials." Journal of Water and Health 12, no. 1 (September 20, 2013): 24–33. http://dx.doi.org/10.2166/wh.2013.060.
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Hardness and alkalinity are known factors influencing the chemical stability of desalinated water. This study was carried out to investigate the effect of Ca2+ and Mg2+ on corrosion and/or scale formation on the surface of different water distribution pipe materials under tropical conditions. The corrosion rates of ductile iron, cast iron and cement-lined ductile iron coupons were examined in reverse osmosis (RO) membrane desalinated seawater which was remineralised using different concentrations of Ca2+ and Mg2+. The changes in water characteristics and the coupon corrosion rates were studied before and after the post-treatment. The corrosion mechanisms and corrosion products were examined using scanning electron microscope and X-ray diffraction, respectively. We found that the combination of Ca2+ and Mg2+ (60/40 mg/L as CaCO3) resulted in lower corrosion rates than all other treatments for the three types of pipe materials, suggesting that Ca2+/Mg2+ combination improves the chemical stability of desalinated seawater rather than Ca2+ only.
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Oron, G., and A. Bick. "Optimal membrane selection for Brackish water desalination." Water Science and Technology 41, no. 10-11 (May 1, 2000): 165–71. http://dx.doi.org/10.2166/wst.2000.0633.
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An integrative approach for optimal membrane selection concerning desalting of brackish water is proposed. This approach is based on management modeling for the following subsystems: Intake, pretreatment, Reverse-Osmosis (RO) unit, post-treatment and brine disposal. The management modeling takes into account membrane performance considerations that include treatment levels and technical capabilities. Attention is also given to membrane replacement and permeates salinity. The model is based on defining an objective (cost) function to be optimized. The optimum of the objective function is evaluated, subject to a series of technological and economical constraints. The results provide guidelines for optimal membrane selection, pretreatment technology and information regarding the system layout, optimal investment and water cost. According to the results, a design based on gravity filters and high flux membranes is preferred with respect to minimum permeate cost. Analyzing the results, indicates the sensitivity of the solution to interest rate and electric power cost.
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Pearson, Jeffrey L., Peter R. Michael, Noreddine Ghaffour, and Thomas M. Missimer. "Economics and Energy Consumption of Brackish Water Reverse Osmosis Desalination: Innovations and Impacts of Feedwater Quality." Membranes 11, no. 8 (August 12, 2021): 616. http://dx.doi.org/10.3390/membranes11080616.
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Brackish water desalination, using the reverse osmosis (BWRO) process, has become common in global regions, where vast reserves of brackish groundwater are found (e.g., the United States, North Africa). A literature survey and detailed analyses of several BWRO facilities in Florida have revealed some interesting and valuable information on the costs and energy use. Depending on the capacity, water quality, and additional scope items, the capital cost (CAPEX) ranges from USD 500 to USD 2947/m3 of the capacity (USD 690–USD 4067/m3 corrected for inflation to 2020). The highest number was associated with the City of Cape Coral North Plant, Florida, which had an expanded project scope. The general range of the operating cost (OPEX) is USD 0.39 to USD 0.66/m3 (cannot be corrected for inflation), for a range of capacities from 10,000 to 70,000 m3/d. The feed-water quality, in the range of 2000 to 6000 mg/L of the total dissolved solids, does not significantly impact the OPEX. There is a significant scaling trend, with OPEX cost reducing as plant capacity increases, but there is considerable scatter based on the pre- and post-treatment complexity. Many BWRO facilities operate with long-term increases in the salinity of the feedwater (groundwater), caused by pumping-induced vertical and horizontal migration of the higher salinity water. Any cost and energy increase that is caused by the higher feed water salinity, can be significantly mitigated by using energy recovery, which is not commonly used in BWRO operations. OPEX in BWRO systems is likely to remain relatively constant, based on the limitation on the plant capacity, caused by the brackish water availability at a given site. Seawater reverse osmosis facilities, with a very large capacity, have a lower OPEX compared to the upper range of BWRO, because of capacity scaling, special electrical energy deals, and process design certainty.
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Yatskov, Mykola, Natalia Korchyk, Oksana Mysina, and Nadia Budenkova. "Improvement of the technological treatment scheme of iron-containing wastewater from etching operations." EUREKA: Life Sciences, no. 3 (May 31, 2021): 21–28. http://dx.doi.org/10.21303/2504-5695.2021.001883.
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The aim of the research is to improve the technological scheme of treatment of iron-containing wastewater from etching operations by creating combined systems, including reagent wastewater treatment, their mutual neutralization, regeneration of etching solutions, deep post-treatment using a magnetic device. The main volume of wastewater is treated in centralized systems with partial return of water to the production process. Spent solutions from etching operations are subject to regeneration with return to the production process and partial dosing into the main wastewater stream from flushing operations. The consumption of commercial HCl is reduced by 50%. The use of hydrogen peroxide can increase the effect of extracting iron from etching solutions by 30% (total purification effect of 70%). Given that deep purification from iron-containing impurities is provided using a magnetic device, the possibilities of practical implementation of reverse osmosis to obtain "pure" water in centralized systems, which can be used for preparation of process solutions and in a mixture with technical water - for flushing operations, increase. In experimental and industrial conditions the expenses of reagents, their concentrations, dosing time are established
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Jesse, Samuel D., and Paul C. Davidson. "Treatment of Post-Hydrothermal Liquefaction Wastewater (PHWW) for Heavy Metals, Nutrients, and Indicator Pathogens." Water 11, no. 4 (April 24, 2019): 854. http://dx.doi.org/10.3390/w11040854.
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Recycling post-hydrothermal liquefaction wastewater (PHWW) may allow the use of nutrients in the aqueous phase that may otherwise go unused. PHWW is an attractive option for use as fertilizer in systems like crop production. However, there are potential contaminants in the PHWW that may inhibit crop growth or pose a food safety risk. This study investigated the concentrations of heavy metals and nutrients in the PHWW, as well as the presence of indicator pathogens. In addition, four different water treatment methods were used: (1) dilution of raw PHWW, (2) sand filtration after dilution, (3) sand and carbon filtration after dilution, and (4) reverse osmosis after dilution. Our results indicate that the concentrations of cadmium, lead, and arsenic in raw PHWW were well below the maximum recommended concentrations set by the US Environmental Protection Agency (US EPA) for Water Reuse. In addition, the treatment methods in this study achieved percent removals ranging from 82–100% for cadmium, 99–100% for mercury, 75–99.5% for lead, and 71–99% for arsenic. Nitrogen in raw PHWW was predominantly in the total N form, preventing it from being accessible to plants. After nitrification was induced, the concentration of NO3 + NO2 increased by 1.75 mg/L in the untreated 5% PHWW mixture, but remained unchanged or decreased for all other treatments and mixtures. There were no E. coli or coliform colonies detected in the raw PHWW, or in any PHWW mixtures. All PHWW mixtures with and without treatment are within US EPA guidelines for metals for irrigation water reuse. However, fertilizer supplementation may be required for PHWW to be suitable for crop production, as the low concentrations of NO3 + NO2 may prove challenging for growing crops.
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Qin, Jian-Jun, Maung Htun Oo, Guihe Dutková, Eberhard Tao, Kiran Arun Kekre, Bryan Cashion, and Robert Wenta. "Pilot Study on Treatment of Wastewater from an Ethylene Plant with Membrane Bioreactor Technology." Open Chemical Engineering Journal 2, no. 1 (November 13, 2008): 119–24. http://dx.doi.org/10.2174/1874123100802010119.
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Pilot studies were conducted with an anoxic/aerobic concept membrane bioreactor (MBR) technology and a hollow fiber Petro® MBR system with capacity of 12 m3/d was operated continuously (24-hour) during the study. Trials on different membrane fluxes were conducted to obtain the sustainable flux while mixed liquor suspended solid (MLSS) was maintained at 9-11 g/L. The results of the MBR pilot trials showed that no obvious fouling of the membrane was found when the plant was operated at the flux of 12 L /m2/h (LMH) over 3 months and 15 LMH over one month during the pilot study. Design guidelines such as hydraulic retention time (HRT), sludge retention time (SRT), anoxic and aeration volume ratio, re-circulation flow rate and air scouring were obtained for a full-scale plant. It was concluded that treatment of wastewater from an ethylene plant without addition of any chemicals using MBR technology is feasible. The product quality consistently met the requirement for discharge and was suitable for the feed of further reverse osmosis (RO) post-treatment.
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Ward, Laura, Martin Page, John Jurevis, Andrew Nelson, Melixa Rivera, Margaret Hernandez, Mark Chappell, and James Dusenbury. "Assessment of biologically active GAC and complementary technologies for gray water treatment." Journal of Water Reuse and Desalination 5, no. 3 (March 26, 2015): 239–49. http://dx.doi.org/10.2166/wrd.2015.088.
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The reuse of gray water for applications ranging from irrigation to showering is a viable means to reduce net water demand when water supplies are stressed. The objective of this study was to investigate the treatment of gray water using biologically active granular-activated carbon (GAC) and complementary technologies. Technologies were challenged individually or in combination using a synthetic gray water formulation based on NSF/ANSI Standard 350. Specific technologies included: GAC; biologically active GAC (BAC); a newly developed intermittently operated BAC (IOBAC) process; ion exchange (IX); coagulation with a cationic polymer; microfiltration; ultrafiltration (UF); and multi-barrier combinations thereof. For control of organic contaminants such as surfactants, BAC and IOBAC performed well over test periods as long as 6 months. Combinations of IOBAC treatment with coagulation pretreatment and UF post-treatment resulted in sustained chemical oxidant demand and turbidity value reductions in excess of 90 and 99.5%, respectively. Such an approach would be useful for gray water treatment for low tier applications like irrigation or toilet flushing, or as a pretreatment system upstream of reverse osmosis (RO) membranes and/or advanced oxidation processes for high tier reuse applications such as showering.
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Szép, Angéla, and Robert Kohlheb. "Water treatment technology for produced water." Water Science and Technology 62, no. 10 (November 1, 2010): 2372–80. http://dx.doi.org/10.2166/wst.2010.524.
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Large amounts of produced water are generated during oil and gas production. Produced water, as it is known in the oil industry, is briny fluid trapped in the rock of oil reservoirs. The objective of this study was to test produced waters from a Montana USA oilfield using a mobile station to design a plant to cost efficiently treat the produced water for agricultural irrigation. We used combined physical and chemical treatment of produced water in order to comply with reuse and discharge limits. This mobile station consists of three stages: pretreatments, membrane filtration and post treatment. Two spiral-wound membrane units were employed and the rejections of various constituents were examined. The performance of two membranes, 20 kDa weight cut-off (MWCO) ultrafiltration and a polyamide-composite reverse osmosis membrane was investigated. The mobile station effectively decreased conductivity by 98%, COD by 100% and the SAR by 2.15 mgeqv0.5 in the produced water tested in this study. Cost analysis showed that the treatment cost of produced water is less expensive than to dispose of it by injection and this treated water may be of great value in water-poor regions. We can conclude that the mobile station provided a viable and cost-effective result to beneficial use of produced water.
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Sanawar, Huma, Szilárd S. Bucs, Martin A. Pot, Jure Zlopasa, Nadia M. Farhat, Geert-Jan Witkamp, Joop C. Kruithof, Mark C. M. van Loosdrecht, and Johannes S. Vrouwenvelder. "Pilot-Scale Assessment of Urea as a Chemical Cleaning Agent for Biofouling Control in Spiral-Wound Reverse Osmosis Membrane Elements." Membranes 9, no. 9 (September 6, 2019): 117. http://dx.doi.org/10.3390/membranes9090117.
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Routine chemical cleaning with the combined use of sodium hydroxide (NaOH) and hydrochloric acid (HCl) is carried out as a means of biofouling control in reverse osmosis (RO) membranes. The novelty of the research presented herein is in the application of urea, instead of NaOH, as a chemical cleaning agent to full-scale spiral-wound RO membrane elements. A comparative study was carried out at a pilot-scale facility at the Evides Industriewater DECO water treatment plant in the Netherlands. Three fouled 8-inch diameter membrane modules were harvested from the lead position of one of the full-scale RO units treating membrane bioreactor (MBR) permeate. One membrane module was not cleaned and was assessed as the control. The second membrane module was cleaned by the standard alkali/acid cleaning protocol. The third membrane module was cleaned with concentrated urea solution followed by acid rinse. The results showed that urea cleaning is as effective as the conventional chemical cleaning with regards to restoring the normalized feed channel pressure drop, and more effective in terms of (i) improving membrane permeability, and (ii) solubilizing organic foulants and the subsequent removal of the surface fouling layer. Higher biomass removal by urea cleaning was also indicated by the fact that the total organic carbon (TOC) content in the HCl rinse solution post-urea-cleaning was an order of magnitude greater than in the HCl rinse after standard cleaning. Further optimization of urea-based membrane cleaning protocols and urea recovery and/or waste treatment methods is proposed for full-scale applications.
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Kumar, Rajesha, Mansour Ahmed, G. Bhadrachari, and Jibu P. Thomas. "Desalination for agriculture: water quality and plant chemistry, technologies and challenges." Water Supply 18, no. 5 (November 24, 2017): 1505–17. http://dx.doi.org/10.2166/ws.2017.229.
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Abstract The growing scarcity of fresh water has motivated the use of non-conventional and re-used water resources for agriculture by applying some efficient technologies. The desalination technologies for agricultural irrigation play a major role in satisfying growing water demands in water scarce regions. Due to stringent ionic concentration standards for agricultural irrigation water, desalination for agriculture is more energy demanding and additional post-treatment is requisite. Reverse osmosis (RO) has emerged as an efficient technology, but the burning of fossil fuels to fulfil the energy requirements is becoming expensive and emission of greenhouse gases is recognized as harmful to the environment. Thus, efforts should be directed towards cost reduction by integrating renewable energy resources into the process. Many of the bench and pilot scale trials like integrated RO with low energy such as forward osmosis (FO), nanofiltration (NF), microfiltration (MF) and solar energy revealed significant improvements in cost savings. However, all these modern technologies have their own problems which can be overcome by further research and development. This paper aims to review the main benefits and constraints associated with desalination technologies for agriculture. The available water resources, the desired qualities of water for agriculture and the challenges and future of desalination in agriculture are discussed.
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Kim, Mi-Ran, JeongAe Heo, Sang Sook Kim, Eui-Cheol Shin, Chang Guk Boo, and Han Sub Kwak. "Effect of Filter Types on Physicochemical Properties, Volatile Compounds, and Sensory Evaluations of Purified Water by Point-of-Use Water Treatment." Foods 10, no. 8 (August 22, 2021): 1958. http://dx.doi.org/10.3390/foods10081958.
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This study investigated purified water from four different filter types for removing minerals, anions, and volatile organic compounds (VOCs), and affecting sensory perception and consumer acceptability. Ultrafiltration (UF), CSM-ultrafiltration (CU), alumina nanofiber (AN), and reverse osmosis (RO) filters were used for a point-of-use water treatment system with a pre-carbon filter (PR) and post-carbon filter (PO). Filters efficiently removed VOCs, which could negatively affect the sensory perception of water. The total VOC concentration of tap water (TW) (14.97 µg/Kg) was reduced by 70% by the PR, 75.3–88.7% by the PR-main filter, and >97% by the PR-RO-PR. Using the polarized sensory position test, the subjects clearly discriminated TW from the samples; however, most of the purified water was not. The difference in the mean ratings of consumer acceptability among the purified samples was <1 except for PR-RO-PO in consumer testing. These results suggested that although there are differences in the capability of different filter types to eliminate minerals, anions, and VOCs, overall consumers did not identify sensory differences among them, and demonstrated similar consumer acceptability of the purified water produced. Simply applying a pre-carbon filter for TW treatment is enough to minimize VOCs, which negatively influence consumer acceptability.
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Xu, Jia, Xueli Gao, Guohua Chen, Linda Zou, and Congjie Gao. "High performance boron removal from seawater by two-pass SWRO system with different membranes." Water Supply 10, no. 3 (July 1, 2010): 327–36. http://dx.doi.org/10.2166/ws.2010.397.
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Boron in the desalinated water produced by the seawater reverse osmosis (SWRO) system is one of the most challenging issues for drinking or irrigation water uses. In recent years, many post-treatment methods and designs for boron elimination have emerged and attracted lots of attention, but only a few cases have demonstrated high performance and economic efficiency. The main aim of this work was to evaluate the efficiency of boron removal from seawater using a two-pass SWRO system employing different RO membranes at Qingdao Jiaozhou Bay, the Yellow Sea of China. In this study, HYDRANAUTICS SWC3+ and ESPAB were chosen as the first and second pass membrane, respectively. The impact of feed properties including temperature, pH, salinity, boron concentration, and operational conditions such as feed pressure on boron rejection and permeate flux was determined. In addition, a relative long term run of the two-pass SWRO system was investigated and compared with performance of system that uses Filmtec membrane as reported in the literature. Although the pilot system in this study experienced more severe feed conditions with lower pH, higher feed boron concentrations and lower operational pressures: all potential negative factors for boron rejection, it still achieved good performance for boron reduction. The results of three-month long term operation indicated that, at optimum conditions, two-pass SWRO system at Qingdao Jiaozhou Bay achieved a high performance and stability without anti-scalants to produce permeate which has much a lower boron concentration than the World Health Organization (WHO) guideline.
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Kuthati, Yaswanth, Vaikar Navakanth Rao, Prabhakar Busa, and Chih-Shung Wong. "Teneligliptin Exerts Antinociceptive Effects in Rat Model of Partial Sciatic Nerve Transection Induced Neuropathic Pain." Antioxidants 10, no. 9 (September 9, 2021): 1438. http://dx.doi.org/10.3390/antiox10091438.
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Neuropathic pain (NP), is a chronic pain resulting from nerve injury, with limited treatment options. Teneligliptin (TEN) is a dipeptidyl peptidase-4 inhibitor (DPP-4i) approved to treat type 2 diabetes. DPP-4is prevent the degradation of the incretin hormone glucagon-like peptide 1 (GLP-1) and prolong its circulation. Apart from glycemic control, GLP-1 is known to have antinociceptive and anti-inflammatory effects. Herein, we investigated the antinociceptive properties of TEN on acute pain, and partial sciatic nerve transection (PSNT)-induced NP in Wistar rats. Seven days post PSNT, allodynia and hyperalgesia were confirmed as NP, and intrathecal (i.t) catheters were implanted and connected to an osmotic pump for the vehicle (1 μL/h) or TEN (5 μg/1 μL/h) or TEN (5 μg) + GLP-1R antagonist Exendin-3 (9–39) amide (EXE) 0.1 μg/1 μL/h infusion. The tail-flick response, mechanical allodynia, and thermal hyperalgesia were measured for 7 more days. On day 14, the dorsal horn was harvested and used for Western blotting and immunofluorescence assays. The results showed that TEN had mild antinociceptive effects against acute pain but remarkable analgesic effects against NP. Furthermore, co-infusion of GLP-1R antagonist EXE with TEN partially reversed allodynia but not tail-flick latency. Immunofluorescence examination of the spinal cord revealed that TEN decreased the immunoreactivity of glial fibrillary acidic protein (GFAP). Taken together, our findings suggest that TEN is efficient in attenuation of PSNT-induced NP. Hence, the pleiotropic effects of TEN open a new avenue for NP management.
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Harris, James M., Lauren J. Harris, Michael C. Dovey, Claire C. Cutting, Barry H. Paw, Matthew G. Vander Heiden, Wolfram Goessling, and Trista E. North. "Glucose Catabolism with Resultant Formation of Reactive Oxygen Species and Local Hypoxia Modulates the Induction and Expansion of Hematopoietic Stem Cells." Blood 116, no. 21 (November 19, 2010): 408. http://dx.doi.org/10.1182/blood.v116.21.408.408.
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Abstract Abstract 408 Metabolic disorders, including obesity, diabetes, and their related complications have become the leading cause of preventable death in the U.S. While effects of increased blood sugar on the cardiovascular system and other organs are well established, consequences for the hematopoietic system are less well characterized. Specifically, the effects of gestational diabetes on embryonic blood formation have not been elucidated in detail. To determine the impact of elevated glucose concentrations on hematopoietic stem cell (HSC) induction and expansion, we treated zebrafish embryos with D-glucose from 12 to 36 hours post fertilization (hpf). HSCs in the Aorta-Gonad-Mesonephros (AGM) region were expanded in a dose-responsive manner, as assessed by in situ hybridization for the conserved HSC markers, runx1 and cmyb; this effect was verified by analysis of CD41 expression (n≥25–50 embryos/condition). A significant 3-fold enhancement in HSC number was observed after 1% glucose treatment by qPCR for runx1 and FACS analysis of fluorescent HSC reporter embryos, Tg(cmyb:eGFP) and Tg(-6.0itga2b:eGFP)la2 (CD41:GFP). Other mono-, di-, and tri-saccharides exerted similar effects, expanding the number of HSCs. However, L-glucose, the inactive enantiomer, did not affect runx1 expression, implying that the effect of the metabolizable saccharides is independent of osmotic dynamics. Furthermore, treatment with glucose from 12 to 120 hpf resulted in a sustained increase in HSC number throughout the duration of treatment. Increased cellular proliferation was observed in the AGM region following 1% glucose treatment, as assessed by elevated BrdU incorporation and cyclin D1 expression. Additionally, acridine orange staining revealed a decrease in apoptotic cell number. HSC formation was impaired by morpholino knockdown of the glucose transporter glut1, indicating the requirement of glucose uptake for HSC formation. Exposure to chemical inhibitors of glycolysis (ethyl-3-bromopyruvate) and of oxidative phosphorylation (cyanide and oxaloacetate) reversed the beneficial effects of glucose on HSCs. In contrast, pharmacological and genetic modulations of the metabolic endocrine hormones IGF and insulin did not alter the effects of glucose treatment. Treatment with the glycolytic intermediate pyruvate expanded HSCs, while exposure to glucosamine, the first component of the hexosamine biosynthetic pathway, had no effect on blood stem cells. These results suggest that glucose catabolism specifically is responsible for HSC expansion. A potential consequence of heightened glucose metabolism is increased generation of reactive oxygen species (ROS), which may serve as important signaling factors mediating the observed effects on HSCs. In support of this hypothesis, treatment with the antioxidant N-acetylcysteine, which alone decreased HSC formation, could not be rescued by concomitant glucose exposure, while the oxidant, 1-phenyl-2-thiourea, elicited an expansion in HSC number. Using the fluorescent ROS sensor, dihydroethidium, we observed ROS in circulating erythrocytes, a subpopulation of CD41+ cells and in the adjacent somitic muscle. ROS are known inducers of the hypoxia sensor, hif1α, which regulates important hematopoietic genes including vegf and epo, as well as the glut1 glucose transporter, indicating a potential feedback loop controlling HSC induction. Chemical induction of hypoxia by cobalt chloride similarly enhanced HSC formation. Intriguingly, excess glucose can overcome the reduction of HSC number normally observed in silent heart mutants lacking blood circulation, possibly by ROS/hif1α-mediated induction of vegf and NO in the hematopoietic niche. The beneficial effect of glucose on hematopoiesis was conserved in adult zebrafish: FACS analysis of kidney marrow following sublethal irradiation revealed a more rapid recovery of the progenitor population after glucose exposure. Our data suggest that, in conjunction with the cardiovascular system, energy metabolism plays a key role in regulating hematopoetic induction and homeostasis. These results could lead to novel therapeutic approaches for HSC modulation, and may unveil specific risks of obesity and diabetes for hematopoiesis during gestation and in the adult. (equal contribution: WG, TEN). Disclosures: Goessling: Fate Therapeutics: Consultancy, Patents & Royalties. North:Fate Therapeutics: Consultancy, Patents & Royalties.
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Han, Kyu Lee, Cattlena M. Changpriroa, Harry L. Malech, and Elizabeth M. Kang. "Activation of the Adenosine A2A Receptor Promotes the Development of Donor-Derived T Regulatory Cells in a Graft-Versus Host Disease Mouse Model." Blood 114, no. 22 (November 20, 2009): 1339. http://dx.doi.org/10.1182/blood.v114.22.1339.1339.
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Abstract Abstract 1339 Poster Board I-361 Introduction Graft versus host disease (GVHD) remains a significant complication of allogenic stem cell transplantation and is a considerable cause of transplant morbidity and mortality. The recognition of the role of Foxp3+ regulatory T cells in immunomodulation has given rise to interest in using these cells to abrogate or modify the severity of graft versus host disease as well as in methods to increase their development during transplant. A less well known avenue of research is the targeting of the adenosine A2A receptor (A2AR). In ischemia models, activation of the Gs-coupled adenosine receptors play a role in terminating inflammation and improving survival of damaged and/or transplanted organs by directly down regulating the activity of the receptor bound T cell. We have shown previously that the use of a specific A2AR agonist known as ATL146e decreases the incidence and severity of GVHD as well as improves survival of mice in a GVHD transplant model (paper in submission). Methods In order to further understand the role of the agonist in GVHD abrogation we performed studies looking at the possible role of T regulatory cells in relation to the use of the agonist. Using a parental into irradiated F1 offspring transplant model (C57BL/6J [B6, H-2b] → B6D2F1/J [BDF1, H-2b/d]) we can induce GVHD manifested by weight loss and mortality in 100% of mice by infusing an additional 10 million donor T cells into mice previously engrafted with 10 million bone marrow donor cells and 800cGy of radiation. We administered the ATL146e or a PBS control by osmotic mini pumps resulting in continuous subcutaneous infusion for 14days starting one day before the donor T cell infusion. Mice that received only the congenic donor bone marrow transplant and no donor T cells did not develop GVHD and served as an additional control. Post transplant, splenocytes and peripheral blood cells were collected and stained for CD4, CD25 and FoxP3 and were analyzed by flow cytometry. The level of Foxp3 mRNA expression in lymphocytes was analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and the concentration of IL-10 in serum was measured by enzyme-linked immunosorbent assay (ELISA). To identify the origin of activated T regulatory cells, we also performed transplants used a B6.PL-Thy1/CyJ (B6-Thy1.1, H-2b) mouse strain as the donor. Results From these studies we confirmed that the A2AR agonist, ATL146e, inhibited the weight loss and mortality associated with acute GVHD progression and seen in the PBS treated controls. More notably, treatment with ATL146e resulted in a 7 fold increase in CD4+CD25+FoxP3+ T regulatory cells in both the spleen and peripheral blood compared to our PBS treated group at days 14 to 20 after hematopoietic stem cell transplantation. From our Thy-1 disparate transplants we determined that the increased T regulatory cells were of donor origin. We also found that the expression of Foxp3 mRNA in splenocytes and the level of IL-10 in the serum was increased 3 fold and 2.4 fold respectively in the ATL146e treated mice. ATL146e agonist activity is very specific to A2AR. When using an alternate adenosine agonist less specific to A2AR, we did not see the same increases of Foxp3 or IL-10, nor did we see any decrease in the severity of the graft versus host disease. Conclusions Thus we believe that the specific activation of A2AR inhibits acute GVHD through the increase of donor-derived CD4+ CD25+ FoxP3+ immunosuppressive T regulatory cells. Our observation provides an additional mechanistic basis for the anti-inflammatory capacity of A2AR agonist in acute GVHD. Additional studies are ongoing to elucidate further the mechanism of the agonist's ability to increase the T regulatory population as well as the effects of combination therapies. Disclosures No relevant conflicts of interest to declare.
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Gordon, Douglas, BCIT School of Health Sciences, Environmental Health, Marc Zubel, Blair Choquette, and Helen Heacock. "Follow-up study of private well users affected by groundwater arsenic in the Surrey-Langley area." BCIT Environmental Public Health Journal, April 27, 2017. http://dx.doi.org/10.47339/ephj.2017.81.
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Background: Arsenic is a potent toxicant and Group 1 human carcinogen which occurs naturally in certain sediments and can contaminate groundwater. In the Surrey-Langley area of British Columbia, a 2007 study of private wells found that 43% of wells tested contained arsenic concentrations above the maximum acceptable concentration (MAC) prescribed in Health Canada’s Guidelines for Canadian Drinking Water Quality. The well owners who participated in the 2007 study were informed of the results and of effective treatment methods that would remove the arsenic contamination. This is a follow-up study that surveyed affected well users approximately 10 years later in order to identify whether the well users had subsequently made any water treatment or behavioral changes to improve the quality of their drinking water, and also to determine whether knowledge translation of the arsenic risk had been effective. Methodology: This study contacted and enrolled private well users who were living at properties which had previously been included in the 2007 study and, in 2007, were found to have arsenic levels above the MAC in the groundwater. Respondents who agreed to participate completed a questionnaire designed to identify what treatment methods or behavioral methods they use to mitigate the risk posed by arsenic contamination. Pre-treatment and post-treatment samples of their drinking water were collected and the arsenic concentrations were analyzed. The effectiveness of treatment devices for arsenic removal was evaluated. The groundwater arsenic concentrations from approximately 10 years apart were compared to identify if arsenic levels had changed. Results: Of the 42 properties that participated in the 2007 study and had groundwater arsenic levels above the MAC, 17 participated in this follow-up study. 14 of the participants also took part in the 2007 study 10 years ago. 79% of participants had not known prior to taking part in the 2007 study that their drinking water contained arsenic levels above the MAC. All 79% then either installed reverse osmosis treatment devices to remove arsenic from their drinking water, or switched to using bottled water for drinking. This indicates that knowledge translation of the health risk was effective. Of the 8 properties using treatment devices rather than bottled water, to mitigate the arsenic risk, 2/8 (25%) were ineffective at reducing arsenic. In addition, arsenic groundwater concentrations were not found to have changed significantly in 10 years (p = 0.11). Conclusion: Participation in the 2007 study was viewed as useful and informative by participants. Knowledge translation of the health risk and the need for risk mitigation was effective, but 25% of treatment devices were found to be ineffective at removing arsenic from drinking water. These results suggests that further knowledge translation of the need for routine testing for arsenic in post-treated drinking water may be beneficial to affected private well users.
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Siraj, M. A., A. Momen, D. Zarrin Khat, and M. Husain. "P5997GLP-1(28-36) prevents progression of ischemic heart failure in mice." European Heart Journal 40, Supplement_1 (October 1, 2019). http://dx.doi.org/10.1093/eurheartj/ehz746.0718.
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Abstract Background Glucagon-like peptide-1 (GLP-1), its metabolites and related drugs have demonstrated cardioprotective benefits in several animal models of cardiovascular disease (CVD) and select clinical trials. Indeed, large cardiovascular outcome trials (CVOT) of GLP-1 analogs showed significant reductions in major adverse cardiovascular events (MACE). However, smaller studies in patients with heart failure (HF) (e.g. FIGHT), and secondary analyses of some CVOT (e.g. LEADER), have suggested that the cardiovascular benefits of GLP-1 analogs may be muted in select patients. Speculating on how this may be due to undesirable increases in heart rate caused by activation of sinoatrial GLP-1 receptors (Glp1r), we have explored the Glp1r-independent cardioprotective actions of GLP-1(28–36), a neutral endopeptidase (NEP)-derived metabolite of GLP-1. We have shown that the cardioprotective effects of GLP-1(28–36) are mediated by mitochondrial trifunctional protein-α (MTPα)-dependent metabolic shift from fatty acid- to glucose oxidation in coronary vascular cells. As metabolic perturbations are believed to contribute to the pathophysiology of HF, we hypothesized that treatment with GLP-1(28–36) may have beneficial effects on this condition. Purpose To evaluate if treatment with GLP-1(28–36) can prevent onset of HF and/or reverse established HF in a post-MI mouse model. Methods and results Permanent LAD ligation was performed in 10–12wk old male C57BL/6J wild-type mice (wt). Immediately post-MI, mice were assigned to receive either GLP-1(28–36) or scrambled peptide [Scram(28–36)] at 18.5nmol/kg/d (N=30/group) subcutaneously (s.c.) via osmotic mini-pumps for 4wk. Although, treatment with GLP-1(28–36) did not improve post-MI survival, triphenyltetrazolium chloride (TTC)-stained hearts 28d post-MI reveal smaller infarct size in GLP-1(28–36)- vs. Scram(28–36)-treated mice (35.3±1.9% vs. 41.2±1.7%, N=12–15/group, P<0.05). Echocardiography at 28d post-MI showed improved LVEF in mice treated with GLP-1(2–36) (30.1±2.3% vs. 24.2±3.7%, N=12–15/group, P<0.05). Similarly, treatment with GLP-1(28–36) reduced heart/body weight ratio (7.9±0.3 vs. 8.8±0.4 mg/g, N=12–15/group, P<0.05). Next, we tested if GLP-1(28–36) might reverse ischemic HF in this model. After permanent LAD ligation of 10–12wk old male wt mice, only those with echocardiography-defined LVEF between 20–35% at 28d post-MI were randomized to treatment with GLP-1(28–36) or Scram(28–36) [18.5nmol/kg/d (N=15/group)] via s.c. mini-pumps for 4wk. Echocardiography at 56d post-MI (i.e. 28d post-treatment start) revealed that GLP-1(28–36) preserved LV function with no deterioration in LVEF vs. Scram(28–36)-treated controls [−3.1±4.9% vs. −22.8±4%, relative change, N=15/group, P<0.001]. Conclusion In a post-MI mouse model of HF, treatment with GLP-1(28–36) prevents progression to HF, and preserves LV function after the development of established HF. Acknowledgement/Funding This study was funded by a Fellowship from Ted Rogers Centre for Heart Research and a Project Grant from Heart and Stroke Foundation, Canada