Reverse Osmosis Process Research Articles

Critical Evaluation of Thin Film Composite Membrane on Pesticide Removal

This study focuses on how operating pressure, pesticide characteristics, membrane materials, feed solution and draw solution affect the performance of thin film composite membranes on pesticides removal. The membrane separation discussed in this review involve nanofiltration (NF), reverse osmosis (RO) and forward osmosis processes (FO) (i.e., FO mode and pressure retarded osmosis (PRO) mode). High pressure shows positive effects on NF and RO membranes flux performances, but it could deform PRO membranes. Hydrophobic pesticides that are larger in size, negatively charged with small dipole moments will result in higher retention. Besides, ions in the feed solution increased the rejection efficiency and permeate flux of membrane whereas pesticides concentration has a negative effect on their retention. pH of feed solution determines the zeta potential of membrane. As for the draw solution, NaCl at higher concentration is recommended. This paper is crucial to give an overview on ways to improve the removal of pesticides with various thin film composite membranes.

Membrane biorreactor, reverse osmosis and UV/H2O2 process integration for ethinylestradiol removal: A cost-benefit analysis

The presence of 17α-ethinylestradiol (EE2) in water bodies and its potential risks to human health and the environment have been frequently described in the literature, in addition to its limited removal in conventional wastewater treatment plants. Many studies have evaluated this removal by advanced processes, including photodegradation and membrane separation. A significant number of studies also assess the economic analysis of these technologies. However, few works articulate both perspectives: the specificity involved in estrogen removal and economic analysis. Given this gap, this work evaluates the synergies involved in the integration of reverse osmosis (RO) and advanced oxidative processes by UV/H2O2 (AOP) in the post-treatment of membrane bioreactor (MBR) effluents. To this end, the integrated plant possibilities were represented through a superstructure that integrated EE2 removal and cost models of each process. The use of a Hook and Jeeves optimizer considering these processes standard operating conditions made it possible to determine the percentage of stream division for each equipment and even the absence of any of these in an integrated plant with lower cost and EE2 concentration output below the recommended limit by the European Union (0.035 ng.L−1). For EE2 feed content up to 3 ng.L−1, the lowest cost configuration is to route 20% of the MBR effluent to the AOP, 30% to the RO, and the remainder to a final mixer. For concentrations above 15 ng.L−1, the sufficient and lowest cost configuration is the MBR-RO-AOP series. Intermediate values have a more advantageous integrated process configuration with the parallel and series configurations combined, with a stream distribution dependent on the feed concentration. Moreover, a parameter sensitivity analysis was performed, clarifying paths for design improvements and acting as a systematic guide for future work in this area. This analysis highlights that EE2 removal is more sensitive to temperature (1.04%), feed substrate concentration (−1.18%), solid retention time in the MBR (0.32%), and irradiance in AOP (−0.46%). Investment costs also proved to be decisive in the composition of the total cost, enhancing the relevance of the maturation process of these technologies in light of simple changes in operating parameters.

Application of Nanofiltration and Reverse Osmosis in Wastewater Treatment Containing Ethylene Glycol from South Pars Gas Complex Wastewater

Today, industrial wastewater discharge has become one of the serious problems of governments. Industrial wastewater contains harmful and dangerous compounds that can endanger human health and the environment. In addition, in the oil, gas, and petrochemical industries, ethylene glycol is used for various purposes, and its removal from wastewater has become a challenge. Industries located on the shores of the Persian Gulf are one of the sources of production of this type of wastewater. In this study, the performance of Nanofiltration (NF) and Reverse Osmosis (RO) membrane processes for treatment of wastewater containing ethylene glycol (EG) from South Pars Gas Complex (SPGC) are investigated and compared. Various process parameters such as pressure, flowrate, and EG removal percentage as well as performance and characteristics of the membrane such as flux and fouling are discussed. It has been observed RO has better performance and less fouling than NF. However, the NF membrane has higher flux due to less compression. RO process achieved 80-99% and NF achieved 60-80% EG rejection during various pressure and flowrates.

Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation.

More than 60 years have passed since UCLA first announced the development of an innovative asymmetric cellulose acetate reverse osmosis (RO) membrane in 1960. This innovation opened a gate to use RO for commercial use. RO is now ubiquitous in water treatment and has been used for various applications, including seawater desalination, municipal water treatment, wastewater reuse, ultra-pure water (UPW) production, and industrial process waters, etc. RO is a highly integrated system consisting of a series of unit processes: (1) intake system, (2) pretreatment, (3) RO system, (4) post-treatment, and (5) effluent treatment and discharge system. In each step, a variety of chemicals are used. Among those, sulfites (sodium bisulfite and sodium metabisulfite) have played significant roles in RO, such as dechlorination, preservatives, shock treatment, and sanitization, etc. Sulfites especially became necessary as dechlorinating agents because polyamide hollow-fiber and aromatic thin-film composite RO membranes developed in the late 1960s and 1970s were less tolerable with residual chlorine. In this review, key applications of sulfites are explained in detail. Furthermore, as it is reported that sulfites have some adverse effects on RO membranes and processes, such phenomena will be clarified. In particular, the following two are significant concerns using sulfites: RO membrane oxidation catalyzed by heavy metals and a trigger of biofouling. This review sheds light on the mechanism of membrane oxidation and triggering biofouling by sulfites. Some countermeasures are also introduced to alleviate such problems.

Performance of integrated sequencing batch reactor (SBR) and reverse osmosis (RO) process for leachate treatment: effect of pH

PurposeIn this paper the performance and effectiveness of the reverse osmosis (RO) process for the biologically pretreated leachate was investigated. The RO process was carried out separately for two different pH: 8.0 and 9.3.MethodsA general pollution parameters as well as organic and inorganic indicators were determined in raw, biologically pretreated and RO treated leachate. The performance characteristics of the reverse osmosis system were made on the basis of permeate flux, electroconductivity removal rate, concentration factor and efficiency in removal of analyzed parameters.ResultsThe use of SBR pretreatment had very good efficiency in BOD (97.3%) and ammonia nitrogen (95.4%) removal. The lowest effectivity was observed for chloride (11.6%), boron (3.9%) and TDS (1.2%). Pretreated leachate was subjected to RO system. The normalized average flux was 0.53 (42.3 L/m2·h) for pH = 8.0 and 0.68 (33.5 L/m2·h) for pH = 9.3. The lower membrane fouling at higher pH can be explained by electrostatic repulsion between the negatively charged membrane surface and organic substances. Independently of the process pH, a two-step membrane fouling was observed. The greatest differences in removal rates were observed for boron, which had a higher retention rate at higher pH, and ammonia nitrogen, whose removal rate decreased at higher pH. The obtained permeate pH after RO process was lower than the feed pH in two analyzed value of pH.ConclusionsThe higher flux value at pH = 9.3 is result of high content of organic matter in leachate, which is better rejected at higher pH because of higher electrostatic repulsion between organic matter and membrane surface. This indicates that the organic matter content should be taken into account when determining the operating parameters (pH values) of the RO system.

Coupling of electromembrane processes with reverse osmosis for seawater desalination: Pilot plant demonstration and testing

Reverse osmosis (RO) is the most widespread technology to produce drinking water from seawater (SW). However, the integration of different membrane processes offers interesting alternatives. In this work, electromembrane processes were integrated with RO to desalinate real seawater in a pilot plant with 25 m3/day capacity. Electrodialysis (ED, either two-stage or single stage), shortcut reverse electrodialysis (scRED) and assisted reverse electrodialysis (ARED) pre-desalinated seawater before RO with the ED-ED-RO, ED-RO, and scRED-ARED-RO process schemes. Treated wastewater was used as salt sink in the scRED-ARED tests. The performance of the pilot plant can be summarized as follows: water recovery of ~27–51%, productivity of ~7–14 L/(m2 h) in the electromembrane processes and of ⁓19–31 L/(m2 h) in the RO process, energy consumption of 3.5–8.4 kWh/m3. The ED-RO configuration yielded the maximum productivity of the electromembrane step, while the scRED-ARED-RO integration reached the minimum energy consumption. Overall, the energy performance of the pilot plant (especially in the ED-RO and scRED-ARED-RO schemes) was comparable to that of a standalone SWRO system. The field tests demonstrated that the coupling of electromembrane processes with RO is feasible and suggest the possibility to develop alternative and competitive industrial pants for seawater desalination.

Increased risks of antibiotic resistant genes (ARGs) induced by chlorine disinfection in the reverse osmosis system for potable reuse of reclaimed water

The reverse osmosis (RO) process has been applied extensively in wastewater reclamation for industrial and potable reuse. To prevent biofouling, chlorine disinfection was usually used in pretreatment. However, this study found that chlorine disinfection could significantly increase risks of antibiotic resistant genes (ARGs) in the RO system. With the increase of chlorine concentration from 0 to 5 mg/L, the accumulative relative abundance of 14 common ARGs in the membrane foulants increased by 49.6%. Among these ARGs, tolC, acrA and acrB (resistance to multiple drugs) showed the highest increament after chlorine disinfection. Especially, the relative abundance of tolC in the group with 5 mg/L chlorine increased by 113.3% compared with the control group. These ARGs tended to be enriched in a few bacterial genus, including Candidatus, Thiomonas, Silanimonas, Xanthomonas and Pseudomonas. These results indicated that the foulants on RO membranes might become a potential sink of ARGs. Considering the possibility of membrane breach, the ARGs may contaminate the permeate and bring great biological risks.

Influence of Reverse Osmosis Process in Different Operating Conditions on Phenolic Profile and Antioxidant Activity of Conventional and Ecological Cabernet Sauvignon Red Wine.

Red wine polyphenols are responsible for its colour, astringency, and bitterness. They are known as strong antioxidants that protect the human body from the harmful effects of free radicals and prevent various diseases. Wine phenolics are influenced by viticulture methods and vinification techniques, and therefore, conventionally and ecologically produced wines of the same variety do not have the same phenolic profile. Ecological viticulture avoids the use of chemical adjuvants in vineyards in order to minimise their negative influence on the environment, wine, and human health. The phenolic profile and antioxidant activity of wine can also be influenced by additional treatments, such as concentration by reverse osmosis. The aim of this study was to investigate the influence of four different pressures (2.5, 3.5, 4.5, and 5.5 MPa) and two temperature regimes (with and without cooling) on the phenolic profile and antioxidant activity of conventional and ecological Cabernet Sauvignon red wine during concentration by reverse osmosis. The results showed that retention of individual phenolic compounds depended on the applied processing parameters, chemical composition of the initial wine, and chemical properties of a compound. Higher pressure and retentate cooling favoured the retention of total polyphenols, flavonoids, and monomeric anthocyanins, compared to the opposite conditions. The same trend was observed for antioxidant activity.

A review of reverse osmosis process for seawater desalination

The freshwater availability in many regions of the world has been a rising concern for the last few decades due to disturbing increase in population, urbanization, and industrial advancement. As water consumption is increasing year by year, the obvious solution to the freshwater shortage is to increase its supply. Desalination has been a prominent process to produce fresh water in numerous water-stressed regions to counteract the water shortage issues. Amongst the various desalination methods, the reverse osmosis method is used for generating fresh water from saline or brackish water by removing salts to make it suitable for human utilization, agriculture, and industrial purposes. In the present study, a systematic review of the seawater reverse osmosis process is presented to address the developments in the pretreatment, membrane, and post-treatment processes of reverse osmosis.

Оценка селективности обратноосмотических мембран при разделении бинарных растворов хлоридов натрия

Manufacturers of reverse osmosis filter membranes provide their products with computer programs that allow for technological evaluation calculations for solutions with different concentrations of impurities. The description of the programs does not include the computer methods and algorithms which are necessary for calculating traffic flows. Consequently, it is not possible to evaluate the selectivity of the reversely osmotic stages of membranes. The development of computer algorithms and techniques that would evaluate the operation of reverse osmosis plants taking into account external and internal parameters is an important practical task. The article discusses reverse osmosis processes in installations with membrane filtration associated with the purification of water enriched with salt. The physical mechanisms of purification are considered, and it is shown that the difference between the working and osmotic pressures plays a leading role in this mechanism. Purification of water enriched with salt by a membrane is accompanied by diffusive flows of the salt component of the solution. The reverse osmosis process is simulated, in which salt water is fed under high pressure into a chamber with a membrane permeable only to water. The permeate outlet flow is low-pressure pure water, and the retentate flow is salt-enriched water. The initial parameters are set, namely, the pressure drop on the membrane, the mass fraction of salt at the inlet and the flow rate. An increase in the mixing rate reduces the concentration polarization on the inlet side of the membrane and increases the flow of water through the membrane.

Metal adsorption of Pb and Fe in refillable drinking water in Semarang City using Powdered Activated Carbon (PAC) based on coconut shell and ozonation technology

Drinking Water Refilling Depot (DAMIU) is one of the most common sources of drinking water. Drinking water quality standards have been regulated in PERMENKES No. 492 Year 2010 concerning Drinking Water Requirements. Drinking water samples were taken at two DAMIU, which using a reverse osmosis process, located in Semarang. The sample contained metal contents (Pb and Fe) that exceeded the quality standards. The Pb metal content ranged from 0,17-0,18 mg/L with a quality standard of 0,01 mg/L and Fe metal content ranged from 0,43-0,48 mg/L with a quality standard of 0,3 mg/L. In this study, to reduce the levels of Pb and Fe metals are using adsorption and ozonation technology. Adsorption was carried out using powdered activated carbon from coconut shell with a particle size of 100 mesh, variations of dose used were 2, 3, 4, and 5 g. The variation of adsorption and ozonation contact time were 20, 40, and 60 minutes. The highest adsorption method efficiency with a 2 g dose and a 60 minutes time, with Pb and Fe levels are 97,2% and 97,0%, respectively. Meanwhile, the highest ozone efficiency was at 60 minutes with Pb and Fe levels of 90,7% and 92,3% respectively.

Temporal reverse osmotic salt filtration mechanism of multi-layered porous graphene

Reverse osmosis (RO) technology is currently the most progressive, energy-saving and efficient membrane separation technology . Meanwhile, graphene becomes a promising candidate for fabricating the RO membranes in water desalination due to its high salt rejection and water flux. The concept of “temporal selectivity” is first proposed in our previous work in terms of the time difference between the penetration time of an ion passing through the pore and the tangential slipping time for the ion sliding across the pore. Nevertheless, the temporal selectivity mechanism of multilayered graphene membrane remains ambiguous. In this paper, the RO process of saltwater through porous graphene column RO membrane is studied by using molecular dynamics (MD) simulations method, and the effects of rotating angular velocity and the thickness of RO membrane on desalination performance of seawater are considered first. The MD results show that the salt rejection increases with the rotation speed of porous membrane increasing while the water flux initially increases and then decreases . Meanwhile, the interfacial slip velocity increases linearly with angular velocity increasing. On the other hand, the increasing thickness of porous graphene membrane can enhance the selectivity and reduce the permeability of water molecules. As expected, the tri-layered porous graphene RO membrane can achieve high salt rejection at low interfacial slip velocity. In order to ensure high selectivity and energy conservation and efficient, the pore structure of the porous graphene RO membrane is optimized. The results show that the optimized nanopores can increase the water flux significantly, whereas the salt rejection is not changed appreciably. It is found that the pore size of the innermost layer membrane near the feed region has the most significant effect on the water flux. The water flux increases sharply with the increase of pore diameter and the salt rejection remains totally higher than 80%. Moreover, the RO membrane with a special Type 3 structure exhibits excellent performance in seawater desalination, specifically, the ultrahigh water flux reaches 20029 L·cm<sup>–2</sup>·d<sup>–1</sup> and the super salt rejection arrives at 94%. The research results further clarify and verify the mechanism of the temporal selectivity in RO process, and improve the water flux under the condition of the same membrane thickness by designing gradient hole. The findings can conduce to the in-depth theoretical understanding of porous graphene-based membranes and designing and developing the large-scale seawater desalination devices and water filtration equipment.

Removal, Reuse and Recovery of Carbon-Dioxide by Integrating Membrane Contactors in a High-Ph Single-Pass Seawater Reverse Osmosis Process

Removal, Reuse and Recovery of Carbon-Dioxide by Integrating Membrane Contactors in a High-Ph Single-Pass Seawater Reverse Osmosis Process

Simulation of Reverse Osmosis Process: Novel Approaches and Development Trends

Reverse osmosis is an essential technological separation process that has a large number of practical applications. The mathematical simulation is significant for designing and determining the most effective modes of membrane equipment operation and for a deep understanding of the processes in membrane units. This paper is an attempt at systematization and generalizing the results of the investigations dedicated to reverse osmosis simulation, which was published from 2011 to 2020. The main approaches to simulation were analyzed, and the scope of use of each of them was delineated. It was defined that computational fluid dynamics was the most used technique for reverse osmosis simulation; the intensive increase in using of molecular dynamics methods was pointed out. Since these two approaches provide the deepest insight into processes, it is likely that they will further be widely used for reverse osmosis simulations. At the same time, for the simulation of the membrane plant, it is reasonable to use the models that required the simplest solutions methods. The solution-diffusion model appears to be the most effective and flexible for these purposes. Therefore, this model was widely used in considering the period. The practical problems solved using each of the considered approaches were reviewed. Moreover, the software used for the solution of the mathematical models was regarded.

Application of the reverse osmosis method for the purification of drinking water

The article deals with the problem of clean water, as for Ukraine, which belongs to the states with a limited amount of water resources and a high level of their use. It has been substantiated that deviations from the standards of water quality, both surface and underground sources, reach 70-80%. Almost a third of the population of villages and towns of rural type in Ukraine consumes water from wells, the water in which is recognized as practically unfit for consumption, especially in terms of nitrate indicators, which have a negative impact on human health. Provided a comparative assessment of regulatory documents State sanitary norms and rules 2.2.4-171-10 "Hygienic requirements for drinking water intended for human consumption" and DSTU 7525: 2014 "Drinking water. Requirements and methods of quality control", in force on the territory of Ukraine, Council Directive 98/83/EC, which regulates water quality indicators at the international level. The modern views on the structure of drinking water as a dilute aqueous solution, where water is presented in the form of giant heterophase clusters, are considered and, based on this, the terms "prepared drinking water" and "natural drinking water" are defined. The problem of optimal adjustment of the qualitative and quantitative composition of drinking water is determined, which in the modern world is solved by methods of additional purification of water at the local level. It is shown that according to the principle of operation, household water purifiers can be divided into 4 main groups, namely: installations with a mechanical filter element; household filters of the sorption type; plants of an electrochemical type and plants of a membrane type based on the reverse osmosis process, which are widely represented on the world market today and are actively used at the local level (apartments, houses, kindergartens, schools), but they have a number of features and disadvantages. The mechanism of the processes in the system "initial water – membrane – prepared drinking water" with its outlined components is presented. The consequences of the use of reverse osmosis plants for the purification of drinking water are considered on the example of tap water, which has been purified in a plant with a membrane element TW30-1812-50 manufactured by DOW Chemical (USA) at an operating pressure of 18 atm. The presented results of changes in the quantitative and qualitative composition of water, namely, its fundamental components, as a result of post-treatment by reverse osmosis. Technological and economic disadvantages of reverse osmosis plants are substantiated. It has been confirmed that the reverse osmosis method is used to demineralize water and is capable of retaining almost all ions by 92–99%, and with a two-stage purification system up to 99.9%, that is, water is prepared by reverse osmosis purified from almostall mineral salts, including useful and necessary for normal human life.

Thermodynamic Limitations and Exergy Analysis of Brackish Water Reverse Osmosis Desalination Process.

The reverse osmosis (RO) process is one of the most popular membrane technologies for the generation of freshwater from seawater and brackish water resources. An industrial scale RO desalination consumes a considerable amount of energy due to the exergy destruction in several units of the process. To mitigate these limitations, several colleagues focused on delivering feasible options to resolve these issues. Most importantly, the intention was to specify the most units responsible for dissipating energy. However, in the literature, no research has been done on the analysis of exergy losses and thermodynamic limitations of the RO system of the Arab Potash Company (APC). Specifically, the RO system of the APC is designed as a medium-sized, multistage, multi pass spiral wound brackish water RO desalination plant with a capacity of 1200 m3/day. Therefore, this paper intends to fill this gap and critically investigate the distribution of exergy destruction by incorporating both physical and chemical exergies of several units and compartments of the RO system. To carry out this study, a sub-model of exergy analysis was collected from the open literature and embedded into the original RO model developed by the authors of this study. The simulation results explored the most sections that cause the highest energy destruction. Specifically, it is confirmed that the major exergy destruction happens in the product stream with 95.8% of the total exergy input. However, the lowest exergy destruction happens in the mixing location of permeate of the first pass of RO desalination system with 62.28% of the total exergy input.

Seawater battery desalination with a reverse osmosis membrane for simultaneous brine treatment and energy storage

As it is typically disposed of to the ocean, naturally produced brine water has been an avoidable issue in seawater desalination technology, particularly in the reverse osmosis (RO) process. To address this issue, a seawater battery-desalination (SWB-D) system was used to reduce the concentration of RO brine while also storing electrical energy by harvesting sodium ions from the brine. The SWB equipped with an anion exchange membrane (AEM) can lower the RO brine concentration to seawater levels, but the use of AEM for brine treatment is costly and the slow kinetics of salt transport require long operation times. In this study, we present a proof of concept for using RO membrane as an alternative to AEM in the SWB desalination system. Owing to its low cost and unexpected support for salt removal via diffusion across the RO membrane, using RO membrane is a viable application. The effect of diffusion enables SWB-D with RO membrane to reduce the charging time by 36.8% (up to ∼40.5% salt removal) compared with SWB-D with AEM. In addition, ∼52.5 kWh m−3 of energy (assuming 80% energy recovery) was saved while lowering the concentration of brine to seawater levels (from 1.2 to ∼0.6 M).

Process simulation of modelled reverse osmosis for desalination of seawater

Abstract Model equations for prediction of process parameters of reverse osmosis for desalination of seawater were developed via mathematical derivation from basic equations for the reverse osmosis process. A model equation relating the interfacial solute concentration () with the process pressure difference () was developed. Taking the of reverse osmosis as the basic independent variable, further model equations relating other process parameters such as the solute concentration polarity , water flux , osmotic pressure , water output rate (q), power density (Pd) and specific energy consumption (SEC) were developed. Simulation of hypothetical reverse osmosis data using Microsoft Excel Worksheet and Microsoft Windows 10 on a 64-bit operating system was carried out. Simulation results showed that the optimum fluid bulk concentration was = 0.0004 mole/cm3. The optimum rate of increase in the solute rejection factor per unit rise in ΔP was 0.45%. The optimum solute rejection factor was 97.6%. The optimum water output rate, specific energy consumption and power density were 103.2 L/h, 3.65 kWh/m3 and 6.09 W/m2, respectively.

Concentrating stabilized urine with reverse osmosis: How does stabilization method and pre-treatment affect nutrient recovery, flux, and scaling?

Human urine can be used as a fertilizer, however, due to the high water content (97%), concentration is required to make transportation economically feasible. Reverse osmosis (RO) has been identified as an energy efficient concentration method. Furthermore, to maximize nitrogen recovery from source-separated urine it should be stabilized with an acid or base to prevent urea hydrolysis. However, the method of stabilization will have an impact on the downstream RO process. Calcium hydroxide is often used as a base stabilization method for human urine but would require pre-treatment to remove excess calcium and subsequent membrane scaling. Three pre-treatment methods such as air bubbling, NaHCO3 addition, and NH4HCO3 addition, were investigated in this study. Each method successfully reduced the scaling potential and air bubbling was determined to be the most effective method as it resulted in the highest nutrient recovery during concentration and did not require the addition of any chemicals. Base stabilization with air bubbling pre-treatment was then compared to urine stabilized with citric acid. Acid stabilized urine had a higher nitrogen recovery (7.6% higher). However, solids formed in the real acidified urine and during concentration a brown organic compound formed on the membrane surface. The crystals were identified as uric acid dihydrate and the brown organic fouling resulted in a significant decrease in permeate flux as compared to the base stabilized urine with air bubbling pre-treatment. At a 60% water recovery, 85.5% of the urea and 99.2% of the potassium was recovered in the brine stream and more than 99.9% of the phosphorus was recovered as a separate solid calcium phosphate fertilizer. Whilst nutrient recovery was higher with acid stabilization, the membrane fouling that occurred with this stabilization method meant that base stabilization with air bubbling pre-treatment was the preferred treatment option. It is recommended that acid stabilized urine be concentrated using evaporation processes instead.

Membrane cleaning in membrane distillation of reverse osmosis concentrate generated in landfill leachate treatment.

As a thermally induced membrane separation process, membrane distillation (MD) has drawn more and more attention to the advantages of treating hypersaline wastewaters, especially the concentrate from the reverse osmosis (RO) process. One of the major obstacles in widespread MD application is the membrane fouling. We investigated the feasibility of direct contact membrane distillation (DCMD) for landfill leachate reverse osmosis concentrate (LFLRO) brine treatment and systematically assessed the efficiency of chemical cleaning for DCMD after processing LFLRO brine. The results showed that 80% water recovery rate was achieved when processing the LFLRO brine by DCMD, but membrane fouling occurred during the DCMD process, and manifested as the decreasing of permeate flux and the increasing of permeate conductivity. Analysis revealed that the serious flux reduction was primarily caused by the fouling layer, which consisted of organic matter and inorganic salts. Five cleaning methods were investigated for membrane cleaning, including hydrogen chloride (HCl)-sodium hydroxide (NaOH), ethylene diamine tetraacetic acid (EDTA)-NaOH, citric acid, sodium hypochlorite (NaClO) and sodium dodecyl sulphate (SDS) cleaning. Among the chemical cleaning methods investigated, the 3 wt.% SDS cleaning showed the best efficiency at recovering the performance of fouled membranes.