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1

Determining the Efficiency of Reverse Osmosis in the Purification of Water from Phosphates

Gomelya Mykola, Shabliy Tetyana, Radovenchyk Iaroslav, Vakulenko Anna

Journal of Ecological Engineering

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2023

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Vol. 24, nr 2

238--246

EN

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.

2

Assessment of the Pressure Driven Membrane for the Potential Removal of Aniline from Wastewater

Salih Miqat Hasan, Al-Yaqoobi Atheer M., Hassan Hassanain A., Al-Alawy Ahmed Faiq

Journal of Ecological Engineering

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2023

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Vol. 24, nr 8

118--127

EN

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.

3

Removal of Iron Compounds from Mechanical Filters of Household Reverse Osmosis Systems Water Purification

Radovenchyk Iaroslav, Ivanenko Olena, Karpenko Victorivna Margaryta, Radovenchyk Vyacheslav

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

163--172

EN

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.

4

Application of Low-Pressure Reverse Osmosis Membranes for Drinking Water Softening

Gomelya Mykola, Shabliy Tetyana, Radovenchyk Iaroslav, Vakulenko Anna

Ecological Engineering & Environmental Technology

|

2023

|

Vol. 24, iss. 5

154--162

EN

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%.

5

Efficiency of Reverse Osmosis and Ion Exchange in Water Purification from Nitrates

Gomelya Mykola, Shabliy Tetyana, Makarenko Iryna, Vakulenko Anna

Journal of Ecological Engineering

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2022

|

Vol. 23, nr 10

172--180

EN

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.

6

Development of Resource-Saving Technologies in the Use of Sedimentation Inhibitors for Reverse Osmosis Installations

Trus Inna, Gomelya Mukola, Skiba Margarita, Pylypenko Tetiana, Krysenko Tamara

Journal of Ecological Engineering

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2022

|

Vol. 23, nr 1

206--215

EN

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.

7

Analysis and Simulation Performance of a Reverse Osmosis Plant in the Al-Maqal Port

Yousif Yasameen T., Abbas Abdulhussain A., Yaseen Dina Ali

Journal of Ecological Engineering

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2022

|

Vol. 23, nr 5

173--186

EN

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%.

8

Remediation of laundry wastewater with a low-pressure aromatic polyamide thin-film composite reverse osmosis membrane for membrane fouling minimisation and reuse application

Morris Bradley Gareth, Aziz Mujahid, Kasongo Godwill

Environment Protection Engineering

|

2022

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Vol. 48, nr 2

43--57

EN

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.

9

Development of Scaling Reagent for Waters of Different Mineralization

Trus Inna, Gomelya Mukola, Levytska Olena, Pylypenko Tetiana

Ecological Engineering & Environmental Technology

|

2022

|

Vol. 23, iss. 4

81--87

EN

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.

10

Design of a solar powered reverse osmosis system in Egypt

Ibrahim Said M. A., Shabak Ahmed G. M.

Journal of Mechanical and Energy Engineering

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2021

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Vol. 5, No 2

125--140

EN

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.

11

The performance assessment of reverse osmosis stations at Al-Mahalabea area

Ahmed Mohammed F.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2020

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Vol. 29, No. 3

332--342

EN

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.

12

The impact of production of silver nanoparticles using soil fungi and its applications for reducing irrigation water salinity

Yaseen Rabaa, Kotp Yousra H., Eissa Doaa

Journal of Water and Land Development

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2020

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no. 46

216--228

EN

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.

13

Doświadczenia z odwróconą osmozą jako czwartym etapem filtracji

Ogier Julien, Doelchow Uli, Warachim Łukasz, Czarnocki Konrad

Technologia Wody

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2019

|

Nr 2 (64)

8--11

PL

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.

14

Quality of Leachate From Landfill with Reverse Osmosis Concentrate Recirculation

Tałałaj Izabela Anna

Journal of Ecological Engineering

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2019

|

Vol. 20, nr 8

205--211

EN

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.

15

Comparative Analysis of the Effectiveness of Reverse Osmosis and Ultraviolet Radiation of Water Treatment

Dirisu Gabriel B., Okonkwo Ugochukwu C., Okokpujie Imhade P., Fayomi Ojo S.I.

Journal of Ecological Engineering

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2019

|

Vol. 20, nr 1

61--75

EN

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.

16

Uzdatnianie wody do hemodializ

Pasieka Grzegorz

Instal

|

2019

|

nr 4

44--47

PL

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.

17

Membrane processes innovation in environmental protection : review

Konieczny Krystyna H., Wszelaka-Rylik Małgorzata, Macherzyński Bartłomiej

Archives of Environmental Protection

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2019

|

Vol. 45, no. 4

20--29

EN

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.

18

Wpływ pH na efektywność pogłębionego utleniania koncentratu odcieków składowiskowych po odwróconej osmozie

Koc-Jurczyk J., Jurczyk Ł., Masłoń A.

Technologia Wody

|

2018

|

Nr 2 (58)

35--40

PL

Wybór optymalnej metody oczyszczania odcieków ze składowisk odpadów komunalnych powinien uwzględniać zmienność ich składu i ilości w czasie, wymagania dotyczące oczyszczonych odcieków oraz możliwości ekonomiczne. Z uwagi na różnorodność związków znajdujących się w odciekach składowiskowych, konieczne jest zatem zastosowanie kombinacji kilku procesów. Metody biologiczne są efektywne w przypadku oczyszczania odcieków z młodych składowisk. Sprawność procesów biologicznych zdecydowanie zmniejsza się wraz z wiekiem składowiska. W związku z tym, preferowanymi metodami są metody fizyczno-chemiczne, czyli np. pogłębione utlenianie, adsorpcja lub metody membranowe. Celem pracy była ocena efektywności usuwania substancji organicznych metodą pogłębionego utleniania z odczynnikiem Fentona z koncentratu odcieków pobranych z funkcjonującej na składowisku instalacji odwróconej osmozy. W badaniach określono wpływ odczynu, w którym prowadzono reakcję, na efektywność usunięcia substancji organicznych wyrażonych wskaźnikami OWO, ChZT i BZT5, a także możliwości podniesienia podatności koncentratu na biodegradację.

EN

The choice of the optimal treatment method of leachate treatment from municipal waste landfills should take into account the variability of their composition and quantity over time, requirements for treated leachate and economic opportunities. Due to the variety of chemical compounds present in landfill leachate, it is therefore necessary to use a combination of several purification processes. Biological methods are effective in the treatment of landfill leachate from young landfills. The efficiency of biological processes declines significantly with the age of the landfill. Therefore, the preferred methods are physico-chemical methods – advanced oxidation processes, adsorption or membrane technology. The aim of the study was to evaluate the removal effectiveness of organic substances using the advanced oxidation processes with Fenton’s reagent from the concentrate of landfill leachate taken from the reverse osmosis plant operating in the landfill. In this studies, the effect of pH, in the reaction, the efficiency of removal of organic substances, expressed indicators TOC, COD and BOD5 as well as the possible increase in the susceptibility of the concentrate to biodegradation were determinated.

19

Influence of Leachate Quality on Reverse Osmosis Performance

Tałałaj I. A., Biedka P., Bartkowska I.

Rocznik Ochrona Środowiska

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2018

|

Tom 20, cz. 1

634--646

EN

In paper an influence of leachate from landfills with different exploitation time on reverse osmosis performance during their treatment was presented. An unstabilized leachate from landfill of two years exploitation and stabilized leachate from landfill with operation time over 10 years were taken to analysis. The analyses were conducted with use of RO system constructed to reflect the actual operating conditions of the reverse osmosis system exploited on municipal landfills. These two kind of leachate was directed to the reverse osmosis system by maintaining during their filtration the same operating parameters (temperature, pressure, flow rate, recovery rate and pH of leachate). The obtained results indicated that filtration of stabilized leachate is characterized by better performance of the RO system, i.e. shorter filtration time, higher permeate flow and higher salt retention. The higher concentration of organic matter in unstabilized leachate contributes to membrane pores blocking decreases the efficiency of the osmotic system. Moreover, high organic content in the leachate from young landfills, with a high concentration of cations, leads to an unfavorable phenomenon of neutralization of the membrane surface.

PL

W pracy przedstawiono wpływ odcieków ze składowisk o różnym czasie eksploatacji na parametry pracy odwróconej osmozy podczas ich oczyszczania. Do badań przyjęto nieustabilizowane odcieki ze składowiska o 2-letnim czasie eksploatacji oraz odcieki ustabilizowane ze składowiska o czasie eksploatacji przekraczającym 10 lat. Analizy prowadzono na układzie odwróconej osmozy, skonstruowanym w ten sposób by odzwierciedlać rzeczywiste warunki pracy układów eksploatowanych na składowiskach odpadów. Odcieki skierowano na układ RO zachowując podczas ich filtracji te same parametry pracy (temperatura, ciśnienie, przepływ, stopień odzysku oraz odczyn odcieków). Uzyskane wyniki wskazały, że proces filtracji odcieków ustabilizowanych charakteryzuje się lepszymi parametrami pracy układu RO, tj. krótszy czas filtracji, wyższy przepływ permeatu oraz wyższy stopień retencji soli. Większa zawartość substancji organicznych zawartych w odciekach młodych (nieustabilizowanych) przyczynia się do blokowania porów membrany i obniża wydajność układu osmotycznego. Ponadto wyższa zawartość substancji organicznej w odciekach z młodych składowiska oraz wyższe stężenie w nich kationów prowadzi do niekorzystnego zjawiska neutralizacji powierzchni membrany.

20

Elimination of Bisphenol A from Wastewater through Membrane Filtration Processes

Dudziak M., Kudlek E., Łaskawiec E., Felis E., Kowalska K., Garbaczewski L.

Journal of Ecological Engineering

|

2018

|

Vol. 19, nr 1

69--74

EN

New priorities for the environment have resulted in a reassessment of modern technology for treatment of urban wastewater. Urban wastewater treatment mainly involves the elimination or reduction of anthropogenic organic micropollutants in the aquatic environment. In this paper, the effectiveness of bisphenol A elimination from wastewater, after biological treatment, through a complex ultrafiltration/reverse osmosis purification process was evaluated. The effectiveness of the wastewater treatment process in the tested system was also evaluated with a number of other physical and chemical analyses for pH, turbidity, colour, absorbance, TOC, phenol index, conductivity and the concentration of selected heavy metals. Within this study, the change in the hydraulic performance of the membranes was also investigated. The effectiveness of the reduction of bisphenol A concentrations during the process of ultrafiltration was small, due to the significant difference between the size of the pores of the membrane and the size of eliminated micropollutants. In the process of reverse osmosis, the wastewater treatment system reported that the concentration of bisphenol A was reduced by 68%. In the tested treatment system, the ultrafiltration/reverse osmosis completely removed colour, lead and chromium. Other contaminants were eliminated by more than 31%. In both membrane processes, there was evidence that the membrane pores were blocked, but this occurred to a greater extent during the process of reverse osmosis.