Securing sustainable access to water resources is a critical concern for all nations bordering the Mediterranean Sea, and Algeria is no exception. Leveraging its extensive 1,200–kilometer coastline, Algeria has embraced desalination as a key strategy, treating both seawater and brackish water sources. This approach provides potable water to inland towns and cities, extending as far as 60 kilometers from the coast. Currently, Algeria boasts an impressive network of 21 desalination plants, with a combined daily production capacity of 2.6 million cubic meters. The majority of these facilities utilize reverse osmosis, a widely employed desalination technology. This study focused on the Bousfer mini-desalination plant situated on Algeria’s western coast. Various water samples were analyzed throughout the desalination process: seawater intake, post-desalination (osmosis) water, remineralized drinking water, and the resulting brine wastewater. A physicochemical and bacteriological analysis was conducted to assess water quality at each stage. Statistical comparisons were performed using paired-sample T-tests for seawater and osmosis water, and one-sample T-tests were used to compare drinking water and wastewater against established international standards. The analysis revealed significant reductions (p-value<0.001) in most physicochemical parameters for the reverse osmosis water, including conductivity, total dissolved solids (TDS), alkalinity, total hardness, chlorides, calcium, and magnesium. Conversely, these parameters were significantly elevated in the brine wastewater. The bacteriological analysis confirmed the absence of harmful bacteria like E. coli, enterococci, and sulphite-reducing clostridia in the final drinking water. However, this study also highlighted a negative environmental externality, the presence of debris and foam layers on the water surface near the desalination plant outlet, attributed to chemical discharges, which poses a potential nuisance for tourists visiting nearby Bousfer beaches.
In connection with the rapidly growing market of reverse osmosis membrane elements, particularly those intended for use in commercial water treatment installations, the problem of their regeneration and reuse has become acute. Today, the service life of such elements does not exceed 6–12 months, after which they turn into plastic waste and end up in landfills in the amount of no less than 60.000 tons per year, which leads to the emergence of serious environmental problems. This paper proposes methods and conditions for achieving almost complete restoration of the properties of used commercial reverse osmosis membrane elements by means of their regeneration and modif ication. The possibility of using restored elements in vending machines for filling safe physiologically complete drinking water has been demonstrated.
The aim of this investigation is to assess the feasibility and benefits of integrating a renewable energy system into a seawater reverse osmosis (SWRO) desalination station in Aqaba, Jordan. It has been determined that the optimal SWRO system configuration produce 109,500.00 m3 daily fresh-water output with high rejection rates for various contaminants. The total water cost is 0.85 $/m3, with a specific energy consumption of 2.67 kWh/m3. Furthermore, the economic and environmental assessments of optimum design of the wind-diesel generator-battery. This conf iguration not only offers the lowest cost of energy but also demonstrates a substantial renewable fraction and significant reduction in CO2 emissions. These results underscore the feasibility and benefits of integrating renewable energy into desalination operations, contributing to both economic sustainability and environmental preservation.
Processes of water purification from phosphates using a low-pressure reverse osmosis membrane were studied. It was shown that the concentration of phosphates in the permeate largely depends on their initial concentration in the water and increases along with the degree of permeate selection. It was established that when using the Filmtec TW3–1812–50 membrane for phosphate concentrations up to 20 mg/dm3, their concentration in the permeate does not exceed 2.5 mg/dm3 with a degree of permeate selection up to 90% when cleaning solutions in distilled and artesian water. This value is below the permissible level for drinking water. When the concentration of phosphates increases to 100 and 1000 mg/dm3, their content in the permeate increases sharply to the values significantly higher than the permissible level in both drinking and wastewater. When sodium orthophosphate was added to artesian water, the effectiveness of its purification on this membrane with respect to chlorides, sulfates, hardness ions, and hydrocarbons was high. This indicates that the cartridges with these membranes can be used both in industrial installations and in households for further purification of artesian and tap water to drinking water quality.
The vast utilizing of aniline in diverse industrial applications makes it predominantly recognized in the eco-geological system. This work investigated the feasibility of reverse osmosis (RO) and nanofiltration (NF) membranes for the removing of aniline from wastewater. The performance of the TFC spiral wound membrane was examined with different operating parameters. The effect of feed concentration (10–200 mg/l) and operating pressure (1–4 bar) on flux and aniline rejection were explored. Additionally, the fouling test for the adopted membranes was conducted for 20 h using NaOH as cleaning agent. The results revealed that a high rejection ratio at noticeable low operation pressure was achieved by using TFC membranes for both of the RO and NF technologies. The maximum aniline rejection was 99.8% and 93.25% under a 1 bar pressure and the concentration of feed 10 mg/l for the RO and NF membranes, respectively. These rejection ratios correspond to the permissible concentration of aniline in the wastewater. The water flux obtained was 6.33 and 13.5 LMH for reverse osmosis and nanofiltration membranes, respectively. The augmentation of operation pressure resulted in decreasing of rejection and rising of the flux. The fouling test showed a reduction in flux of about 0.92 and 4.35% for RO and NF membranes, respectively, from its initial value before membrane cleaning. The results also demonstrated that the reverse osmosis membrane is better than the nanofiltration membrane in terms of removal efficiency.
Today, the most convenient and widespread option for cleaning and purifying drinking water is to install reverse osmosis systems directly at the water intake points. When operating reverse osmosis systems, most owners are not concerned about the negative consequences of using such systems. After 3–6 months of using mechanical filters in the first stage of water treatment, such filters are thrown out together with other household waste. They pose a significant threat to the environment. Currently, companies in Ukraine would not collect and dispose of such filters. This direction is undeveloped. There are no corresponding data in the scientific literature. According to authors’ calculations, about 20,000 household reverse osmosis systems are operated per 1 million people today, so it is easy to calculate that 44,000 cartridges with a total polypropylene volume of 26 m3 enter the environment during the year. It is difficult to imagine the real environmental damage from the cartridges of even one city. Therefore, the regeneration of mechanical filters of reverse osmosis systems is quite relevant and essential today. This work aimed to develop an environmentally safe technology for regenerating mechanical filters with the possibility of repeated use. Filter lifespan can be prolonged by special cleaning with sulfuric acid with a fixed pH level. This article highlights the research results on the regeneration the mechanical filters, describes the characteristics of the cleaning process using sulfuric acid and shows the options for environmentally safe waste processing from such regeneration.
The processes of water purification with increasing selection of permeate were studied, considering selectivity and productivity of membranes, dynamics of changes of contents of components in the concentrate. It is shown that when chlorides and sulfates are removed from water, the increase in their content in the concentrate does not differ practically from the measured and calculated values. At the same time, the nature of dependences on the change in hardness, concentration of calcium and magnesium ions, alkalinity obtained experimentally differ significantly from the dependences obtained by theoretical calculations at permeate selection levels of > 70%. А significant difference in the determined and calculated concentrations of hardness ions in the concentrates was observed after hardness values greater than 30–40 mg-eq/dm3. This indicates the partial removal of hardness ions and carbonates from the concentrates, which may be the reason for the formation of deposits on the membrane. Permissible values of the degree of permeate selection were determined, at which there is no intense deposition of carbonates and hydroxides of hardness ions on the membrane. With the initial water hardness > 8 mg-eq/dm3, the degree of permeate selection could reach 60–70% without the risk of sedimentation on the membrane. Effectiveness of the low-pressure reverse osmosis membrane in the purification of mine water with an increased level of mineralization and hardness was determined. A significant difference between the determined and calculated hardness in concentration was observed already at the degree of permeate selection of 22–33%.
The process of extracting nitrates from water by the methods of reverse osmosis and ion exchange was investigated in the paper. In the formation of reverse osmosis, low-pressure membranes were used, and in ion-exchange processes, highly alkaline anionite AB–17–8 was applied in salt form. The dynamics of changes in the concentration of nitrates in the permeate and the concentration with an increase in the degree of permeate selection from 9 to 90% at initial nitrate concentrations of 18, 50 and 100 mg/dm3 were determined. The indicators of selectivity and productivity of membranes were calculated depending on the degree of permeate selection. It was shown that the low-pressure reverse osmosis membrane is characterized by low selectivity values at high productivity values in the selected part of the nitrate concentration. It was established that the ion exchange method is significantly more effective than reverse osmosis in removing nitrates from water. It ensures the reduction of nitrate content in purified water to a value of less than 1 mg/dm3 when the degree of their extraction is reached at the level of 99%. As the ionite is saturated with nitrates, the efficiency of their extraction decreases. Anionite sorbs nitrates effectively enough, being both in the chloride mixture and in the sulfate form. Nitrates are effectively desorbed by 2H solutions of sodium chloride and sodium or ammonium sulfate.
The processes of desalination of weakly mineralized waters using a reverse osmosis membrane were studied. The operational efficiency of membranes is limited mainly by membrane contamination. It was shown that the preliminary mechanical water purification helps to increase the productivity and selectivity of the membrane. One of the main causes of membrane contamination is the formation of carbonate deposits on their surface. One way to prevent membrane contamination is to dose antiscalants. It was established that the use of hydrolyzed polyacrylonitrile (HPAN) and hydrolyzed polyacrylamide (HPAA) as a stabilizer of scale formation is effective for concentrates of reverse osmosis desalination of water.
The Basrah province (southern of Iraq) was interested in establishing desalination plants to provide drinking water due to the high levels of salinity in its water resources. This work was carried out in order to evaluate and simulate the functionality of the reverse osmosis plant in the Al-Maqal port. From the field and laboratory measurement, this study concluded that the considered parameters of product water by reverse osmosis (RO) plant were within the Iraqi standard (IRS) limits. The calculation of operation indices showed that the recovery rate of plant (72%) and the permeate flux of plant (20 lmh) was within for limitation of brackish surface water. In turn, the plant has a low salt rejection (90.1%) and a high pressure drop (5 bar); therefore, the membranes require backwashing or chemical cleaning. Then, the performance of RO membrane was simulated by the Winflows software. The best operating parameters were identified. The coefficient of determination (R2) between simulated and measured TDS was 0.83. Therefore, the simulated TDS of permeate multiplied by 5.3 was given a good estimation for actual TDS within acceptable an error rate of 17%.
In areas with limited freshwater resources, affordable technologies can remediate greywater for reuse applications and increase the water supply. These wastewaters contain various chemicals, which make them challenging to treat. Reverse osmosis (RO) membrane systems could be the solution to removing these harmful chemicals. Membrane fouling has been investigated and using a commercial antiscalant to treat laundry wastewater effluent with a polyamide (PA) thin-film composite (TFC) reverse osmosis membrane. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM) were used to assess the antiscalant effects. The anionic surfactant rejection was above 99.8% for experimental tests conducted. The average COD removal rate was in the range of 91-96%, irrespective of the antiscalant dosing. However, the presence of antiscalant at the dose of 8 mg/dm3 significantly reduced fouling intensity. The flux decline ratio amounted to 56 and 72% for the RO process with antiscalant and no antiscalant dosing, respectively.
Membrane technologies are widely used for desalination of water. These technologies are environmentally friendly, economical, energy efficient and material efficient. In the absence of pre-treatment of water, the membrane is contaminated, which leads to an increase in the amount of concentrate formation. Discharge of mineralized water leads to physical and chemical pollution of water bodies. Dissolution and removal of these sediments is a complex issue, so the use of sediment inhibitors is important. The use of antiscalants allows to prolong the service life of membrane elements, which, in turn, will reduce the intake of fresh water and reduce the volume of wastewater. The efficiency of gipan as a reagent in the stabilization treatment of low-mineralized, highly mineralized waters at a temperature of 60°C was determined. The dependences of water stability on sediments on the chemical composition of water, inhibitor concentration and time of ultrasonic treatment of gipan were established.
Scarcity of fresh water, forced many countries to get their water needs, or part of it, by means of saline water desalination. Reverse osmosis (RO) systems are useful tools in this concern. In case the grid electricity is not available or costly, photovoltaic (PV) power is necessary to derive RO systems. The present paper is concerned with providing a methodology for complete sizing and design of a photovoltaic reverse osmosis (PVRO) system in Egypt. Egypt has very favorable solar energy. A computer program was constructed to solve the mathematical equations of the model to get the numerical values. The program is capable of calculating the solar irradiation for any city in Egypt. Calculations and selection of the RO system with all connected pumps, the peak PV power needed, and the actual PV area were performed for different water demands ranging from 1-100 m3/day, and various water total dissolved solids (TDSs) of 5000, 15000, and 30000 mg/l. The cost of the complete PVRO system was also determined. The concern of the paper is related to water desalination and solar energy, which are responsible for our existence. The work also aims toward sustainable and clean environment via utilizing solar energy.
The present study assesses RO stations at four sites in Al-Mahalabea area – Nineveh governorate, Iraq during the summer of 2013. The performance of RO stations are ranked by two methods: the Simple Additive Weight (SAW) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Two groups of samples were collected from feed and permeate water for two periods (at zero time of operation and after ten weeks of operation) with eleven parameters for each sample were analysed. The highest overall rejection R efficiency appeared with the first set of parameters more than 90% (SO4, TDS, NO3, TH, and turbidity), while the second set was the least (Cl, Na, and total alkalinity – TA) ranged between 65 and 85%. It is observed that both the SAW and the TOPSIS methods are accurate to predict the performance efficiency.
In the present work, the dried biomass of soil isolated fungus Eurotium cristatum was used for synthesizing silver nanoparticles (AgNPs). The synthesized AgNPs were spherical in shape with average diameter of 16.56 nm and displayed maximum absorbance at 418. Fourier transform infrared (FTIR) study indicated the presence and binding of proteins with myco-produced silver nanoparticles. The optimum conditions for AgNPs biosynthesis were found to be at temperature of 40°C, pH of 8.0, substrate concentration of 500 ppm and fungal biomass wt. of 0.8 g. The AgNPs showed antibacterial activity against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Shigella flexneri. AgNPs was built-in thin film nanocomposite (TFNC) membrane and the impacts of nanomaterial composition on membrane properties and desalination process were studied. The AgNPs produced membrane TFNC had better filtration performances than pure thin film composite membrane TFC. The TFNC membrane had enhanced water flux (32.0 vs. 16.5 dm3∙m–2∙h–1) and advanced NaCl rejection (91.7 vs. 89%) compared to the TFC membrane. A pot experiment was conducted to evaluate the effect of the irrigation with desalinated water on yield and productivity of essential oil of the sweet basil (Ocimum basilicum L.) and lavender (Lavandula multifida L.). The irrigation with desalinated water reduced significantly the soil reaction, soil electrical conductivity (EC), sodium adsorption ratio and exchangeable sodium percent in rhizospheric soil, it also enhanced the growth and oil yield of both plants compared with those irrigated with salt water.
W ciągu ostatnich kilkudziesięciu lat jakość wód powierzchniowych uległa znacznej poprawie dzięki wprowadzeniu nowoczesnych technologii oczyszczania ścieków i zaostrzeniu wymagań co do jej jakości. Jednak dzięki najnowszej technologii analitycznej możliwe jest również przeprowadzenie testów laboratoryjnych stwierdzających obecność substancji, które choć występują w niewielkich ilościach, mogą stanowić znaczne zagrożenie dla ludzi i środowiska.
The purpose of this study was to determine the changes of leachate quality on a selected municipal landfill with recirculation of concentrate from the reverse osmosis (RO) process. The research was carried out on an exploited municipal waste landfill, from which the samples of leachate, permeate and concentrate were collected in the years 2013-2015. The obtained samples were subjected to the physicochemical analysis, including the determination of general pollution parameters as well as organic and inorganic indicators. The obtained results showed that the concentrate recirculation resulted in intensification of the degradation processes in the waste body, expressed by the increase of biodegradability rate (BOD5/COD) and the value of conductivity and dissolved solids. Over time, the value of conductivity and dissolved solids stabilized; however, they reached the values higher than in conventional landfills. A characteristic feature of the long-recirculation landfills was a continuous increase in the concentration of ammonia nitrogen and COD values in the leachate.
Water contamination and pollution pose health hazards to humanity and hence the need for their treatment. This study compared reverse osmosis (RO) and ultra-violet (UV) radiation in treating borehole water (BHW) and surface water (SW). The study area is Omoku community in Rivers State of Nigeria. The RO- and UV-treated waters were determined by their physicochemical characteristics and total Coliform, with the control to check the impact of each one. The obtained results showed slight variations, which were either significant or not. The pH of the treated BHW was slightly acidic with the value of 6.52. Water conductivity ranged from 40.33 µs/cm3 to 42.40 µs/cm3 for the BHW treated with RO, UV and control samples, respectively. SW conductivity attained a range of 425.07–800.0 µs/cm3. Turbidity of BHW were beyond the detectable limit but was higher than the WHO limit of <5.00NTU, while total suspended solid (TSS) of SW ranged from 9.08–46.43 ppm. Total dissolved solids (TDS) values of water were between 3.50 ppm and 16.67 ppm for RO treated BHW and higher than that of SW. There was a reduction of salinity of BHW from 40.7 mg/l to 11.8 and 21.6 mg/l following RO and UV treatment, while SW salinity was also reduced from 75.0 mg/l to 20 mg/l in RO treated water and 16 mg/l in UV treated water. In this study, RO and UV water treatment proved to be effective in producing potable water from both BHW and SW, although RO seemed to produce water with reduced mineral content in comparison to the UV treatment. Both methods effectively reduced heavy metals as well as Coliform. The physicochemical parameters tested were below the WHO recommended limits in most cases. It is recommended that both methods be incorporated in a single WT in order to gain the benefits of both technologies.
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Współczesna dializoterapia, a w szczególności nowoczesne techniki dializ wysoko-przepływowych wymagają zastosowania wody do dializ o odpowiedniej czystości chemicznej i mikrobiologicznej. W artykule omówiono przykładowy system oczyszczania wody do dializ przy zastosowaniu odwróconej osmozy.
EN
Contemporary hemodialysis, and in particular modern high-flow dialysis techniques, requires the use of dialysis water with appropriate chemical and microbiological purity. The article discusses an example of a water purification system for dialysis using reverse osmosis.
The partial solution for the growing contamination of the environment is the implementation of new technologies. The most of the currently operated systems for surface and groundwaters treatment as well as for wastewater treatment characterize with complex technological arrangements based on a number of unit operations. In water-wastewater management membrane processes are more often applied, especially those in which the difference of pressure at both membrane sites is used as a driving force. As an example of such application is the use of nanofiltration for groundwaters treatment at Water Treatment Plant Zawada near Dębica or the treatment of municipal landfill leachate and industrial wastewater at Eko Dolina Waste Utilization Plant in Łężyce near Gdynia (reverse osmosis unit capacity of 120 m3/d). Municipal wastewater treatment based on membrane technologies has already been implemented at domestic wastewater treatment plant. It is especially profitable, when the load of contaminant present in a wastewater varies within a year. In the case of membrane systems use, this issue can be neglected. As an example of membrane based system may serve WWTP in Rowy n/Ustka started up in 2013 and modernized in 2017. The latest trends and developments of selected suppliers of membrane systems are also presented.
PL
Częściowym rozwiązaniem wzrastającego zanieczyszczenia środowiska wodnego jest wdrażanie nowych technologii. Większość współczesnych dużych systemów uzdatniania wód powierzchniowych i podziemnych oraz oczyszczania ścieków charakteryzuje się bardzo złożonymi układami technologicznymi zakładającymi sekwencję wielu procesów. W gospodarce wodno-ściekowej w coraz to większym zakresie wykorzystywane są procesy membranowe, przede wszystkim te, których siłą napędową jest różnica ciśnień po obu stronach membrany. Przykładem jest między innymi zastosowanie nanofiltracji do uzdatniania wód głębinowych w SUW Zawada k. Dębicy oraz oczyszczanie odcieków z wysypisk odpadów stałych i ścieków przemysłowych technologią membranową w zakładzie Unieszkodliwiania Odpadów Eko Dolina w Łężycach k/Gdyni (wydajność RO 120 m3/dobę). Oczyszczanie ścieków komunalnych w oparciu o technologie membranowe zostało już wdrożone w krajowych oczyszczalniach ścieków. Jest to szczególnie opłacalne, gdy ładunek zanieczyszczeń obecnych w ściekach waha się w ciągu roku. W przypadku zastosowania systemów membranowych, problem ten można pominąć. Przykładem wdrożenia systemu membranowego może być WWTP w Rowach k/Ustki, którą zbudowano w 2013 r. i zmodernizowano w 2017 r. Ponadto przedstawiono najnowsze rozwiązania oraz trendy rozwoju w niektórych firmach realizujących technologie membranowe u klientów.
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