Flat-sheet Ceramic Membrane Research Articles

Treatment of textile wastewater in a single‐step moving bed‐membrane bioreactor: Comparison with conventional membrane bioreactor in terms of performance and membrane fouling

AbstractMembrane bioreactor (MBR) is a promising technology for the treatment of municipal and industrial wastewater, including highly contaminated textile wastewater. However, membrane fouling remains a critical challenge due to reduced flux. This study investigates the efficacy of a moving bed MBR (MB‐MBR) technology for textile wastewater treatment, focusing on chemical oxygen demand (COD) removal, and its impact on mitigating membrane fouling. In a 50‐day study, a conventional MBR (R1) was compared with an MB‐MBR (R2) augmented with free‐floating biocarriers (accounting for 20% of the reactor volume). Both systems used flat sheet ceramic membrane modules. The results indicate that the MB‐MBR achieved superior performance, with COD and colour removal of 89% and 81%, respectively, compared with 87% and 73% in the conventional MBR. Importantly, the introduction of biocarriers eliminated the need for offline physical membrane cleaning in the MB‐MBR. The free‐floating biocarriers lowered transmembrane pressure, reduced capillary suction time and reduced fouling through their scouring action.

The Performance and Spatial Distribution of Membrane Fouling in a Sequencing Batch Ceramic Membrane Bioreactor: A Pilot Study for Swine Wastewater Treatment.

The extensive application of ceramic membranes in wastewater treatment draws increasing attention due to their ultra-long service life. A cost-effective treatment for high-strength swine wastewater is an urgent and current need that is a worldwide challenge. A pilot-scale sequencing batch flat-sheet ceramic membrane bioreactor (ScMBR) coupled with a short-cut biological nitrogen removal (SBNR) process was developed to treat high-strength swine wastewater. The ScMBR achieved stable and excellent removal of COD (95.3%), NH4+-N (98.3%), and TN (92.7%), though temperature went down from 20 °C, to 15 °C, to 10 °C stepwise along three operational phases. The COD and NH4+-N concentrations in the effluent met with the discharge standards (GB18596-2001). Microbial community diversity was high, and the genera Pseudomonas and Comamonas were dominant in denitritation, and Nitrosomonas was dominant in nitritation. Ceramic membrane modules of this pilot-scale reactor were separated into six layers (A, B, C, D, E, F) from top to bottom. The total filtration resistance of both the top and bottom membrane modules was relatively low, and the resistance of the middle ones was high. These results indicate that the spatial distribution of the membrane fouling degree was different, related to different aeration scour intensities demonstrated by computational fluid dynamics (CFD). The results prove that the membrane fouling mechanism can be attributed to the cake layer formation of the middle modules and pore blocking of the top and bottom modules, which mainly consist of protein and carbohydrates. Therefore, different cleaning measures should be adopted for membrane modules in different positions. In this study, the efficient treatment of swine wastewater shows that the ScMBR system could be applied to high-strength wastewater. Furthermore, the spatial distribution characteristics of membrane fouling contribute to cleaning strategy formulation for further full-scale MBR applications.

Heat and water recovery from gaseous stream using a flat-sheet ceramic membrane as a transport membrane condenser

Ceramic-membrane technology has been employed to recover waste heat and vapor from moist gases. In addition to the hydrophilicity, pore size, and porosity of separation materials, a membrane condenser can achieve a high recovery rate. In this study, a transport membrane condenser (TMC) was successfully constructed using a flat-sheet ceramic membrane (FCM) with a large pore size of 45.54 μm. The membrane characteristics, including the mean pore size, pore size distribution, and porosity, were investigated to determine their recovery mechanism. Their water and heat fluxes, recovery rates, and thermal resistance were compared under several experimental conditions. The inlet conditions significantly affect the TMC recovery performance. Higher recovery fluxes were obtained at lower water temperatures, higher gas temperatures, and higher gas flow rates. However, when the Reynolds number of water increased, the heat flux increased rapidly, and the recovered water decreased slightly. The highest TMC water recovery rate was 84.1%. In addition, to further analyze the separation mechanisms, a two-dimensional model was developed using ANSYS Fluent code. The simulation results were compared with the experimental data to verify the accuracy of the numerical method. The comparison results showed a high degree of consistency.

Evaluating the mechanical integrity and reliability of multi-channelled flat-sheet ceramic membranes for filtration applications

Ceramic membranes represent an emergent filtration technology that is receiving increasing research attention, particularly concerning their filtration behaviour (i.e., permeability, selectivity, and fouling) and industrial scalability. Given the inherent brittleness of ceramic materials, mechanical properties of ceramic membranes, especially those related to fracture, are also important pieces of information although nonetheless rarely evaluated. Therefore, a methodological approach for assessing the mechanical integrity and reliability of multi-channelled flat-sheet ceramic membranes is presented here. Specifically, a flat-sheet SiC ceramic membrane designed for submerged outside-inside vacuum-driven filtration was subjected to four-point bending, tensile, and compressive tests, and the experimentally measured failure loads were converted to failure stresses and analysed by Weibull diagrams. It was found that the ceramic membrane is ∼1.4 times stronger and ∼2.9 times less reliable in compression than in bending, and ∼3.3 times stronger and ∼5.4 times more reliable in bending than in tension. These differences in mechanical integrity and reliability are rationalized by considering the fracture modes (i.e., modes I or II) and critical flaw populations (i.e., flaws of the membrane layer or support) responsible for failure. Finally, relevant implications for ceramic “membranologists” interested in mechanical characterisation are discussed.

Long-term performance of ZVI-stimulating anaerobic/aerobic system - PEI modified ceramic membrane SMBR in reusing food wastewater for irrigation: An industrial project and microbial community shift

A large-scale project was carried out using an integrated treatment system composed of anaerobic and aerobic unit followed by ceramic membrane SMBR for reclaiming 200 m3/d of food wastewater for the purpose of irrigation. Utilization of ZVI technology to facilitate the organic contaminants degradation in UASB and aerobic unit in the operation of successive 240 days was investigated. A membrane flux of around 30 LMH was stably attained in a novel PEI-modified flat sheet ceramic membrane SMBR equipped with in situ intensive mechanical cleaning bush system. The ceramic MBR system investigated had significantly alleviated membrane fouling and no severe membrane fouling occurred throughout the whole filtration process. Overall, the combined treatment system can produce high quality reusable water for irrigation and the final effluent had a COD of around 120 mg/L and BOD5 of around 32 mg/L, respectively. Finally, variations in dominant species in both initial sludge Day-1 and sludge Day-240 in ZVI assisting UASB and aerobic unit was further unraveled by the high throughput sequencing analysis.

Impact of salinity on anaerobic ceramic membrane bioreactor for textile wastewater treatment: Process performance, membrane fouling and machine learning models

Anaerobic membrane bioreactor (AnMBR) shows great potential for textile wastewater treatment, but high salinity in the influent may undermine its performance. This study evaluated the impact of salinity on the treatment performance of an upflow anaerobic sludge blanket (UASB) configured AnMBR using a flat sheet ceramic membrane. The salinity was stepwise increased (0, 5, 10 and 20 g/L) in four phases of the AnMBR operation. Results indicated that increased salinity jeopardized the COD removal efficiency of AnMBR from 92% to 73%, but had a marginal effect on dye removal efficacy (90–96%). Low salinity (5 g/L) boosted the biogas production whilst high salinity (>10 g/L) had a negative impact. Additionally, the increase of salinity resulted in the soluble microbial production (SMP) concentration soar and membrane fouling rate increase, peaking at a salinity of 10 g/L (Phase III) and recovering back to a lower level at a salinity of 20 g/L (Phase IV). This indicated a transition occurrence at a salinity of 10 g/L (Phase III). The microbial diversity analyses further suggested a transition from salinity-sensitive microbes (Aminiphilus, Caldatribacterium, Mesotoga, Methanobrevibacter, Methanobacterium, Methanosaeta) to salinity-tolerant microbes (Longilinea, Ignavibacterium, Rhodovarius, Bosea and Flexilinea). This transition can be associated with the increase SMP concentration and more severe membrane fouling in Phase III, which were mitigated after a new equilibrium was reached when the microbial consortium acclimatized to the high salinity. Finally, a machine learning model of the Adaboost algorithm was established to predict COD removal under different salinities. Importantly, this study revealed that AnMBR process performance and membrane operation can be maintained for high salinity textile wastewater treatment with a halophilic microbial community growth under high-salinity selection pressure.

Efficient Recovery of Organic Matter from Municipal Wastewater by a High-Rate Membrane Bioreactor Equipped with Flat-Sheet Ceramic Membranes

High-rate processes have been investigated for the recovery of organic matter from municipal wastewater. High-rate membrane bioreactors (HR-MBRs) may simultaneously achieve the increased recovery of carbon and high effluent quality, although control of membrane fouling is extremely difficult. To address the severe fouling in HR-MBRs, the combination of granular scouring and frequent chemically enhanced backwashing was examined. The use of robust flat-sheet ceramic membranes enabled the application of those cleaning strategies. Experiments were carried out at an existing wastewater treatment plant. To operate as a high-rate system, the bioreactor solid residence time and hydraulic residence time were set at 0.5 days and 1.6 h, respectively. Although a relatively high flux of 20 L m-2 h-1 was applied, the proposed HR-MBR exhibited a very low fouling rate of 1.3 kPa/day. The system could recover >70% of the carbon from raw wastewater, whereas the concentration of chemical oxygen demand in the effluent was lowered to <20 mg/L. The performance of the proposed HR-MBR observed in this study was clearly superior to those reported in previous related studies.

Development of CuCo2O4 integrated ceramic membrane for peroxymonosulfate activation: An efficient oxidation process for bisphenol A degradation

In this study, a new functionalized flat-sheet ceramic membrane (CuCo2O4-CM) was prepared by an impregnation-calcination strategy and used in the removal of Bisphenol A (BPA). Various characterization results indicated that a CuCo2O4 layer was uniformly anchored on the membrane surface and the internal porous channels. The CuCo2O4-CM possessed a smaller mean pore size (80 nm) and better hydrophilicity than the pristine α-Al2O3 substrate after modification. The catalytic degradation in CuCo2O4-CM /PMS system revealed that 92.1% of BPA and 70.0% of TOC could be removed under optimal conditions (pH = 7.0, CBPA = 30 mg/L and CPMS = 2 mM). Meanwhile, the membrane showed good reusability and improved antifouling properties. During the reaction, four reactive oxygen species (·OH, SO4·-, O2·- and 1O2) were generated and they all responded for the degradation of BPA. In addition, the mechanism of PMS activation and BPA degradation were proposed. This study presented an efficient oxidation process for BPA degradation and outlines the synergistic effect of separation and catalytic oxidation.

New insights into membrane fouling during direct membrane filtration of municipal wastewater and fouling control with mechanical strategies

Direct membrane filtration (DMF) technology achieves energy self-sufficiency through carbon recovery and utilization from municipal wastewater. To control its severe membrane fouling and improve DMF technology, targeted research on fouling behaviour and mechanisms is essential. In this study, a DMF reactor equipped with a flat-sheet ceramic membrane was conducted under three scenarios: without control, with intermittent aeration, and with periodic backwash. This system achieved efficient carbon concentration with chemical oxygen demand below 50 mg/L in permeate. Membrane fouling was dominated by intermediate blocking and cake filtration. And reversible external resistance accounted for over 85 % of total resistance. Predominant membrane foulants were free proteins, whose deposition underlies the attachment of cells and biopolymers. Backwash decreased the fouling rate and increased fouling layer porosity by indiscriminately detaching foulants from the membrane surface. While aeration enhanced the back transport of large particles and microbial activity, causing a relatively thin and dense fouling layer containing more microorganisms and β-d-glucopyranose polysaccharides, which implies a higher biofouling potential during long-term operation. In addition, aeration combined with backwash enhanced fouling control fivefold over either one alone. Therefore, simultaneous operation of backwash and other mechanical methods that can provide shear without stimulating aerobic microbial activity is a preferred strategy for minimizing membrane fouling during DMF of municipal wastewater.

Development of Fouling-Control Strategy for Ceramic Membrane Bioreactor Applied in Partial Nitrification Process

A lab-scale ceramic membrane bioreactor (MBR) with active membrane-fouling control system was developed for the partial nitrification (PN) process. The in situ membrane cleaning method was applied to remove the contaminants on the surface of the membrane with no interruption of the wastewater treatment. The results showed that the device increased critical flux and reduced gel layer resistance (Rg) and internal resistance (Ri) of the flat-sheet ceramic membrane by inhibiting the formation of the cake layer. In long-term experiments, nitrite oxidizing bacteria (NOB) was successfully suppressed, and nitrite accumulation rate (NAR) was achieved at a high level, up to 90.09%; the effluent NO2−-N/NH4+-N was maintained in balance dynamically with an average ratio of ~1.30, which would be beneficial to the proliferation of Anammox bacteria and the following autotrophic nitrogen removal (ANR) process. Moreover, with the assistance of in situ cleaning, energy input from aeration was significantly reduced, while over aeration was avoided for more stable PN performance.

Intensive routine cleaning for mitigation of fouling in flat-sheet ceramic membranes used for drinking water production: Unique characteristics of resulting foulants

Ceramic membranes are physically and chemically robust, and intensive membrane cleaning can therefore be used. The use of ceramic membranes may alleviate the problem of membrane fouling. In this study, fouling in flat-sheet ceramic membranes operated with intensive mechanical cleaning (scouring with granular materials) was investigated in the context of drinking water production. Samples collected from multiple drinking water treatment plants were used as the feed. Bench-scale experiments were carried out in a realistic style: with a constant flow rate and periodical hydraulic backwashing. Granular materials for the purpose of scraping off the fouling layer from the membrane surface were placed in the membrane tank (10 % v/v) and they moved freely by the aid of periodical aeration provided during the routine backwashing. Operation under the condition of a high membrane flux of 125 LMH was possible with little fouling when granular scouring was carried out with pretreatment using PACl coagulation. As for irreversible fouling, in-line chemical membrane cleaning at a low frequency (1-hour cleaning/120 h of filtration) using oxalic acid followed by NaClO exhibited a very high cleaning efficiency (permeability recovery of > 99 %). Analysis of the foulants extracted from the fouled ceramic membrane revealed that the properties and compositions of the foulants causing the irreversible fouling in ceramic membranes were different from those in polymeric membranes. Analysis using liquid chromatography with organic carbon detection (LC-OCD) suggested that humics were dominant (35 % of the total organic carbon) in the foulant extracted from the fouled membranes, instead of biopolymers (11 % of the total organic carbon) that have been shown in recent studies to be the major foulants for polymeric membranes. However, spectral analysis of the foulant using infra-red and fluorescence and filtration data obtained with pretreatments suggested the feature of biopolymers, particularly polysaccharides. These discrepancies indicate the necessity for new analytical methods to distinguish overlaps between humics and biopolymers.

Performance of a hybrid process integrating PAC adsorption with ceramic membrane ultrafiltration for drinking water treatment

Membrane separation technologies have broad application prospects in water treatment. Compared with polymeric membranes, ceramic membranes have higher stability for long-term operation in practical applications. Coupling ceramic membranes with other water treatment processes is an effective way to improve membrane treatment effect and alleviate membrane fouling. This study evaluated the water purification efficiency and membrane fouling behaviors of powdered activated carbon (PAC), flat-sheet ceramic membranes and their hybrid process in treating model organic pollutants and natural water. Results showed that the PAC-ceramic membrane hybrid process could alleviate the membrane fouling caused by humic acid but aggravate that caused by sodium alginate. Addition of PAC notably improved the removal performance of the ceramic membrane for organic matters in natural water as well as pharmaceutical and personal care products, and effectively controlled membrane fouling. The PAC adsorption obviously reduced the irreversible fouling of the ceramic membrane under multi-cycle operation. This study can provide a reference for the practical application of ceramic membranes in drinking water treatment.

Study on Interface Thermodynamic Mechanism of Membrane Fouling in flat sheet ceramic membrane treating Oilfield Produced Water

In this study, a flat sheet ceramic membrane experimental device was constructed, and the thermodynamics of membrane fouling interface was studied for oilfield produced water. The flux of ceramic membrane in three kinds of model solutions were measured with time, as well as the surface tension, contact Angle and Zeta potential of solid. The thermodynamic mechanism of membrane fouling interface combined with XDLVO theory were explored for three kinds of model solutions. The thermodynamic study of the interface of ceramic plate membrane shows that the total interaction energy between membrane and oil droplets decreases with the increase of the distance between two interfaces at initial stage of membrane fouling, and finally transforms from the mutual attraction to the mutual repulsion. The total interaction energy between reservoir and oil droplet is shown as mutual attraction, and the total interaction energy decreases with the increase of the distance between reservoir and oil droplet interface. The zeta potential of crude oil was affected by salinity to some extent. The electrostatic shielding effect of the salt ions leads to a decrease in the ζ-potential of the three solutions. They are in the order: model solution A > model solution B > model solution C. This leads to a decrease in the electrostatic interaction (EL). And since the oil layer has the same composition as the oil droplets, the EL interactions in the three solutions can behave as mutual repulsion.

Performance of Newly Developed Intermittent Aerator for Flat-Sheet Ceramic Membrane in Industrial MBR System

An intermittent aerator was newly developed to reduce energy costs in a flat-sheet ceramic membrane bioreactor (MBR) for industrial wastewater treatment. Large air bubbles were supplied over a short time interval by the improved aerator technology at the bottom of the flat-sheet membrane. Performance tests for the intermittent aerator were carried out in a pilot system with two cassettes immersed in a membrane tank of the 1-MGD demonstration plant at Jurong Water Reclamation Plant (JWRP) in Singapore. Stable operation was achieved at an average flow of 19–22 LMH with every-2-days MC and peak flow of 27 to 33 LMH with daily MC with reduced air flow for membrane aeration. This indicates that energy costs for membrane aeration can be reduced by using the intermittent aerator. Stable MBR operation with a projected 43% reduction in the overall operating costs could be achieved with an improved aerator together with improved MC regime and membrane cassette.

Mitigation of membrane fouling of alginate with combined actions of aeration and powdered activated carbon: Fouling behaviors and mechanisms.

A laboratory-scale flat-sheet ceramic microfiltration membrane system was developed to investigate the membrane fouling behaviors and mechanisms of sodium alginate (SA) in the presence of aeration and powdered activated carbon (PAC). When the SA concentration increased from 20 to 500 mg/L, the permeate flux decreased by 81.7%, and the transmembrane pressure (TMP) and resistance increased 1.7 and 24.5 times, respectively. At an SA concentration of 500 mg/L, it was found that the membrane fouling tended to decrease with the increase in the aeration rate, indicating high control of the fouling by air scouring, while PAC-aeration scouring produced a significant improvement in the permeate flux with substantially reduced fouling. In the microfiltration of 500 mg/L SA at an air flow rate of 2.2 L/min and PAC concentrations of 40, 100, and 250 mg/L, the flux increased by 179.3%, 238.0%, and 302.7%, the TMP decreased by 32.6%, 34.8%, and 45.7%, and the cake and pore blocking resistance decreased by 78.0%, 85.1%, and 87.9%, respectively, compared to the corresponding values without PAC-aeration scouring. Intermediate blocking and complete blocking models were confirmed to elucidate the effect of aeration scouring and PAC-aeration scouring on the mitigation of membrane fouling by SA. PRACTITIONER POINTS: Air scouring was effective at mitigating membrane fouling of sodium alginate. The addition of PAC could alleviate membrane fouling of SA. Synergistic scouring by aeration and PAC offers a promising means for more-efficient and cost-effective control of membrane fouling. The fouling mechanisms in various scenarios were elucidated.

3D spray-coated gradient profile ceramic membranes enables improved filtration performance in aerobic submerged membrane bioreactor

Rational design of cross-sectional microstructure in ceramic membranes has shown to improve membrane filtration efficacy without affecting rejection performance. In this work, we adopted 3D spray-coating technique to generate multi-layered membrane layers on macro-porous flat-sheet ceramic supports. The thickness of each layer was controlled by spray-coating cycles, and a gradient membrane layer was rationalized by successively coating three ceramic slurries containing alumina powders of gradually refined particle sizes, followed by co-sintering. Gradient membrane layers on both sides of the various sized flat-sheet ceramic supports were fabricated. Compared to the non-gradient counterpart, the gradient membranes showed both higher pure water flux (at the same TMP) and lower membrane resistance, which clearly evidenced the benefits of gradient profile in the membrane layer. Further, their performance in aerobic membrane bioreactors (AeMBR) was comparably studied for the first time. The treatment performance was not significantly affected by the types of membranes used, while the gradient membrane showed better filtration performance (i.e., a slower rise in TMP). Although the fouling mechanisms were revealed to be similar, the fouling layer in the gradient membrane was composed of a higher percentage of smaller foulants compared to that of the non-gradient counterpart. The observed differences were closely correlated to the larger internal pore structure in the gradient membrane. The present work provides a feasible 3D spray-coating technique for the fabrication of gradient flat-sheet ceramic membranes, and clarifies the benefits in AeMBR for domestic wastewater treatment.

Evaluation of the advanced oxidation process integrated with microfiltration for reverse osmosis to treat semiconductor wastewater

This study evaluated the filtration performance and energy consumption of three different reverse osmosis (RO) membranes (ESPA2-LD, RE4040-BE, and TMG10D) for treating semiconductor wastewater. A ceramic membrane combined with ozone for RO pre-treatment and the influence of ozone injection on the filtration and energy consumption efficiency of RO were investigated. A flat-sheet ceramic membrane comprising Al2O3/SiO2-ZrO2 was used to treat real and synthetic semiconductor wastewater as feed water. The deionized water (DI) permeabilities of RO membranes were 144.6, 94.22, and 156.6 LMH/bar, respectively. The microfiltration process that used ozone reduced the permeability of all RO processes, and the total organic carbon (TOC) removal rate decreased when ozone was applied. The application of ozone on power consumption was inconclusive, and its effect was unclear indicating an increase 3.37%, 4.48%, and 11.6% when filtrated with ozone, respectively. TMG10D showed the highest permeability followed by ESPA2-LD and RE4040-BE, for both, the real and synthetic wastewaters. However, ESPA2-LD showed the highest salt and TOC rejection followed by RE4040-BE and TMG10D. TMG10D exhibited the lowest energy consumption per ton of filtered water followed by ESPA2-LD and RE4040-BE. ESPA2-LD was determined to be the most suitable membrane in terms of the water quality stability and energy consumption in RO to treat semiconductor wastewater.

Catalytic ceramic membrane integrated with granular activated carbon for efficient removal of organic pollutants

A hybrid process of catalytic ceramic membrane integrated with granular activated carbon (GAC) was proposed for removal of organic pollutants in water. By coating flat-sheet ceramic membrane with Co oxide and loading GAC into membrane channels, the integrated catalytic ceramic membrane module (MCo-GAC) with peroxymonosulfate (PMS) activation and GAC adsorption was successfully prepared. The decontamination performance of the MCo-GAC/PMS system was systematically investigated by using bisphenol A (BPA) as target pollutant. Excellent removal efficiency of the MCo-GAC/PMS system was achieved, and hydroxyl radicals (•OH) and sulfate radicals (SO4•−) were identified as the major reactive species responsible for the degradation process. The MCo-GAC/PMS system showed strong resistance to humic acid (HA) and various anions for BPA removal. Moreover, the MCo-GAC/PMS system exhibited excellent universality for various organic pollutants, where MCo-GAC had superior stability and reusability. The integrated process provides a proposed strategy for enhancing the remediation of organic pollutants.

Characteristics of flat-sheet ceramic ultrafiltration membranes for lake water treatment: A pilot study

In order to explore the characteristics of ceramic membranes in the treatment of surface water with high turbidity and high content of organic matters, a pilot-scale test was carried out on the water treatment process composed of pre-zonation, coagulation, sedimentation, and ultrafiltration using flat-sheet ceramic membranes. The water purification effect of the combined process and the influences of different operating parameters on membrane fouling were comprehensively investigated. The results showed that the effluent turbidity of the combined process could be controlled below 0.1 NTU, and the removal rates of CODMn, DOC and UV254 in the raw water were 58%, 49%, and 45%, respectively. The membrane fouling rate largely depended on the permeate flux; when the constant permeate fluxes were set at 80, 100, 120 and 150 L m−2h−1, the rising rates of the transmembrane pressure (TMP) in the early stage were 0.18, 0.42, 1.20 and 2.04 kPa/h, respectively. The permeate production period had a relatively small effect on the membrane fouling rate, and the “high-intensity short-time” mode was demonstrated more efficient than the “low-intensity long-time” mode during backwashing. Under the optimized conditions, no chemical cleaning was required by the ceramic membranes during 12 days of continuous operation, with the TMP increasing by only 20 kPa. A series of characterizations suggested that the irreversible membrane fouling was mainly caused by proteins, humic substances and silicates. The chemical cleaning strategy with the combined use of NaClO and acid cleaning agents was recommended for the recovery of membrane performance.

Enhanced cross-flow filtration with flat-sheet ceramic membranes by titanium-based coagulation for membrane fouling control

Enhanced cross-flow filtration with flat-sheet ceramic membranes by titanium-based coagulation for membrane fouling control