Application Of Membrane Bioreactor Research Articles

Application of modified PVC membranes with GO-ZnO nanoparticles in MBR: sludge characteristics, fouling control and removal performance

BackgroundMembrane fouling is still one crucial impediment in the application of membrane bioreactors (MBR). MethodsAntifouling properties of GO and GO-ZnO embedded PVC membranes in MBR were investigated. ZnO nanoparticles were decorated onto GO nanosheets and then membranes were made by NIPS method. Significant findingsThe results revealed that the contact angle decreased from 80° for pure PVC to 67° for 0.1 wt% GO-ZnO embedded membrane. Pure water flux increased from 33 L/m2h for neat membrane to 128 L/m2h for 0.075 wt% PVC/GO-ZnO membrane. The performance of membranes was evaluated during 35 days MBR filtration system using several analyses including COD, turbidity, SMP, EPS, PSD, and EEM. Results indicated that the presence of GO-ZnO nanoparticles in the membranes has a positive effect on COD and turbidity removal due to the oxygen-containing groups attracting SMP through intermolecular force interaction. In addition, the inclusion of nanoparticles in the membranes leads to a reduction in EPS concentration. Research on PVC membranes with graphene oxide and zinc oxide nanoparticles in membrane bioreactor processes is crucial for advancing water treatment technology. These nanomaterials promise enhanced membrane performance, longevity, and efficiency in treating wastewater, leading to more sustainable and effective water treatment solutions.

Enhanced anaerobic digestion performance and sludge filterability by membrane microaeration for anaerobic membrane bioreactor application

Slow dissolution/hydrolysis of insoluble/macromolecular organics and poor sludge filterability restrict the application potential of anaerobic membrane bioreactor (AnMBR). Bubble-free membrane microaeration was firstly proposed to overcome these obstacles in this study. The batch anaerobic digestion tests feeding insoluble starch and soluble peptone with and without microaeration showed that microaeration led to a 65.7–144.8% increase in methane production and increased critical flux of microfiltration membrane via driving the formation of large sludge flocs and the resultant improvement of sludge settleability. The metagenomic and bioinformatic analyses showed that microaeration significantly enriched the functional genes and bacteria for polysaccharide and protein hydrolysis, microaeration showed little negative effects on the functional genes involved in anaerobic metabolisms, and substrate transfer from starch to peptone significantly affected the functional genes and microbial community. This study demonstrates the dual synergism of microaeration to enhance the dissolution/hydrolysis/acidification of insoluble/macromolecular organics and sludge filterability for AnMBR application.

Study on efficiency and mechanism of ultrasonic controlling membrane fouling in ceramic membrane bioreactors.

In recent years, ceramic membranes have been increasingly used in membrane bioreactors (MBRs). However, membrane fouling was still the core issue restricting the large-scale engineering application of ceramic MBRs. As a novel and alternative technology, ultrasonic could be used to control membrane fouling. This research focused on the efficiency and mechanism of ultrasonic controlling membrane fouling in ceramic MBRs. The results showed that ultrasonic reduced the sludge concentration in MBR, and the average particle size of sludge was always in a high range. The sludge activity of the system was stable at 6-9 (mg O2·(g MLSS·h)-1), indicating that ultrasonic did not destroy the activity of microorganisms in the system. The extracellular polymer substance (EPS) of the ultrasonic group was slightly higher than that of the control group, while the soluble microbial product (SMP) content was relatively stable. The ceramic membrane of the ultrasonic group has a partial retention effect on the organic components. The application of ultrasonic slowed down the decrease of the hydrophilicity of the ceramic membrane. The main pollutants on the membrane surface exist in the form of aromatic and heteroaromatic rings, alkynes, and so forth. Ultrasonic removes the amide substances from the membrane surface. Membrane fouling resistance is mainly due to membrane pore blockage, accounting for 75.53%. PRACTITIONER POINTS: Enrich the research on the mechanism of ultrasonic technology in membrane fouling control. The MBR can still operate normally with ultrasonic applied. The time for the ceramic membrane to reach the fouling end point is 2.4 times that without ultrasonic. The main cause of membrane fouling was pore blocking, accounting for 75.53%.

Predatory Bdellovibrio-and-like organism mixtures on efficient MBR in-situ membrane fouling diminishment and mechanisms

ABSTRACT Membrane fouling is a major hindrance that restricts the application of membrane bioreactors (MBRs). Bdellovibrio-and-like organisms (BALOs), as obligatory parasitic bacteria, prey upon various bacteria. In this study, the BALO mixtures were screened and found more effective in membrane fouling mitigation compared to the single BALO species and extended the membrane filtration period by as long as 33.3%. The higher BALO diversity reduced the potential foulants generation in the activated sludge by decreasing the sludge viscosity as high as 13.8 ± 0.6% than the pure culture of BALO. Meanwhile, the mixed BALOs demonstrated superior biofilm predation capabilities, with the content of soluble microbial products and extracellular polymeric substances on the biofilm decreasing by 26.1 ± 0.5% and 38.3 ± 0.2% as the most compared to the single BALO species involved system. Additionally, the BALO mixtures expanded the single strains’ host lysis spectrum of both the activated sludge and biofilm. The abundance of membrane-fouling-related bacteria such as Flavobacterium, Rhodobacter, and Labilithrix and pioneer bacteria such as Sphingorhabdus and Pseudomonas was significantly reduced. In summary, this study disclosed the significantly better membrane fouling mitigation effects of the BALOs with higher diversity, suggesting that the expansion of the host range is crucial for the further application of BALOs to enhance the anti-fouling performance of the MBR system.

Membrane biofouling control by D-ribose in membrane bioreactor

BackgroundMembrane biofouling is still one major obstacle in the application of membrane bioreactor (MBR). Because of similar chemical structure to quorum sensing (QS) signaling molecule autoinducer-2 (AI-2), D-ribose might be an ideal QS inhibitor to inhibit membrane biofouling. Methods100 μM of D-ribose were periodically added to MBR to investigate the effect of D-ribose on membrane biofouling in MBR. Significant findingsThe fouling cycle was prolonged significantly, and the membrane was covered with larger and looser foulants with the addition of D-ribose. The soluble microbial products (SMP) content were reduced slightly and the secretions of extracellular polymeric substances (EPS) in activated sludge were effectively inhibited by the addition of D-ribose. Moreover, D-ribose could promote catalase (CAT) and superoxide dismutase (SOD) activity of activated sludge, and reduce the accumulation of malondialdehyde (MDA). Furthermore, long-term addition of D-ribose could increase the abundance of quorum-sensing quenching (QQ) bacteria, strengthen the quenching ability of the system and effectively inhibit membrane biofouling.

Heat-activated persulfate for chemical cleaning of ceramic MBR

Irreversible membrane fouling is a major concern in the application of membrane bioreactors (MBRs), and periodic chemical cleaning is required to sustain MBR operation. However, conventional NaClO cleaning exhibited limited efficacy and caused secondary environmental risks (e.g. disinfection by-products). Therefore, it is necessary to develop safe and efficient chlorine-free cleaning methods. Here, we proposed a heat-activated persulfate (peroxymonosulfate PMS and peroxydisulfate PDS) process for efficient cleaning of fouled ceramic membrane in MBR. Results showed much higher chemical cleaning efficiency in heat-activated persulfate process (79–81%) than that in NaClO (34–52%). A medium solution temperature of 60 °C was enough to efficiently activate PMS and PDS, with the optimal persulfate concentration of 1 mM and solution pH of 7. Both SO4•− and •OH were identified as the main reactive oxygen species for membrane cleaning. Compared with PDS, PMS was easier to be activated, and thus more free radicals were generated in heat/PMS system. Further investigations demonstrated radicals degraded polymers and broke microbial cell structure, thereby effectively removing foulants from membrane. This work provides a new idea for developing safe and efficient chemical cleaning method for ceramic MBR.

In-depth insight into improvement of simultaneous nitrification and denitrification/biofouling control by increasing sludge concentration in membrane reactor: performance, microbial assembly and metagenomic analysis

Currently, severe membrane fouling and inefficient nitrogen removal were two main issues that hindered the sustainable operation and further application of membrane bioreactor (MBR). This study aimed to simultaneously alleviate membrane fouling and improve nitrogen removal by applying high sludge concentration in MBR. Results showed that high sludge concentration (12000 mg/L) enhanced total nitrogen removal efficiency (78 %) and reduced transmembrane pressure development rate. Microbial community analysis revealed that high sludge concentration enriched functional bacteria associated with nitrogen removal, increased filamentous bacteria fraction in bio-cake and inhibited Thiothrix overgrowth in bulk sludge. From molecular level, the key genes involved in nitrogen metabolism, electron donor/adenosine triphosphate production and amino acid degradation were up-regulated under high sludge concentration. Overall, high sludge concentration improved microbial assembly and functional gene abundance, which not only enhanced nitrogen removal but also alleviated membrane fouling. This study provided an effective strategy for sustainable operation of MBR.

Performance analysis of microbial fuel cell - membrane bioreactor with reduced graphene oxide enhanced polypyrrole conductive ceramic membrane: Wastewater treatment, membrane fouling and microbial community under high salinity

The application of membrane bioreactor (MBR) in high salinity wastewater treatment was mainly hindered by membrane fouling. Microbial fuel cell (MFC)-MBR coupling system was established to alleviate membrane fouling and save energy. Reduced graphene oxide/polypyrrole ceramic membrane (rGO/PPy CM) with high conductivity and stability was innovatively placed in MFC-MBRs as both cathode and filter, with PPy CM, rGO/PPy CM and CM placed in other reactors. MFC-MBR (rGO/PPy) and MFC-MBR (PPy) achieved higher pollutant removal efficiencies (90.73 % and 90.45 % for TOC, 87.22 % and 86.56 % for NH4+-N, respectively) and superior anti-fouling performance (1.86 and 1.93 kPa/d for average membrane fouling rates) than both conventional MBRs (CMBRs). The stable voltage generation was around 287 and 242 mV, respectively. Through high throughput sequencing, electric field showed a positive correlation with the abundance and activity of most dominant phylum (Bacteroidetes, Chloroflexi, Actinobacteria, and Firmicutes) and functional genes (amoA, hao, narG, napA, nirK, norB, and nosZ), thereby improving pollutant removal efficiency. The higher conductivity of rGO/PPy CM resulted in enhanced electric field intensity, leading to superior performance of anti-fouling and pollutant removal. This study inventively explored the effects of conductive membrane property on electricity generation performance, microbial community, pollutant removal and membrane fouling, providing theoretical support for the selection of electrode materials in MFC-MBR.

Using artificial intelligence-based algorithms to identify critical fouling factors and predict fouling behavior in anaerobic membrane bioreactors

Membrane fouling is one of the major obstacles that hinder the widespread applications of anerobic membrane bioreactors (AnMBRs) for wastewater treatment. Due to the intrinsic complexity of membrane fouling, identifying critical fouling factors and predicting fouling behavior are of great significance in membrane fouling control. Herein, artificial intelligence (AI) algorithms and their modeling framework were developed to predict membrane fouling behaviors in AnMBRs. Operating parameters, biomass properties, and membrane characteristics were considered as input variables for membrane fouling prediction. The results of hyper-parameter optimization showed that the optimal architecture of artificial neural network (ANN) model for membrane fouling prediction was “14-9-6-1” while the best hyper-parameters of random forest (RF) model were n_trees = 1200 and n_features = 14. After hyper-parameter adjusting, RF had more robustness of predictive capabilities (R2=0.906, mean squared error (MSE) = 0.061) for membrane fouling than the ANN model (R2=0.800, MSE = 0.118). More importantly, the feature importance and Shapley additive explanations analysis indicated SMPp/SMPc (0.281) > EPSp/EPSc (0.110) > organic loading rate (0.106), which were the most critical factors affecting membrane fouling. Partial dependence plot analysis further verified the marginal and interaction effects of various input features on membrane fouling. The revealed partial dependence relationships of critical variables can provide theoretical reference for optimization of practical operation. Overall, this study established a novel AI-based approach for predicting membrane fouling and comprehensively understanding the complicated effects of various influencing factors on membrane fouling while overcoming the “black-box” nature of conventional models.

Bioelectrochemical anaerobic membrane bioreactor enables high methane production from methanolic wastewater: Roles of microbial ecology and microstructural integrity of anaerobic biomass

The disintegration of anaerobic sludge and blockage of membrane pores has impeded the practical application of anaerobic membrane bioreactor (AnMBR) in treating methanolic wastewater. In this study, bioelectrochemical system (BES) was integrated into AnMBR to alleviate sludge dispersion and membrane fouling as well as enhance bioconversion of methanol. Bioelectrochemical regulation effect induced by BES enhanced methane production rate from 4.94 ± 0.52 to 5.39 ± 0.37 L/Lreactor/d by accelerating the enrichment of electroactive microorganisms and the agglomeration of anaerobic sludge via the adhesive and chemical bonding force. 16 S rRNA gene high-throughput sequencing demonstrated that bioelectrochemical stimulation had modified the metabolic pathways by regulating the key functional microbial communities. Methanogenesis via the common methylotrophic Methanomethylovorans was partially substituted by the hydrogenotrophic Candidatus_Methanofastidiosum, etc. The metabolic behaviors of methanol are bioelectrochemistry-dependent, and controlling external voltage is thus an effective strategy for ensuring robust electron transfer, low membrane fouling, and long-term process stability.

Application of membrane bioreactor integrated with ultraviolet disinfection for simultaneous greywater treatment and SARS-CoV-2 removal

Application of membrane bioreactor integrated with ultraviolet disinfection for simultaneous greywater treatment and SARS-CoV-2 removal

The Application of Membrane Bioreactor for Greywater Treatment

The Application of Membrane Bioreactor for Greywater Treatment

Fouling mitigation in membrane bioreactors by nanobubble-assisted backwashing

Widespread application of membrane bioreactors (MBRs) is still difficult because of the problem of membrane fouling, which increases operational and maintenance costs. A novel approach to mitigate fouling in MBRs, nanobubble-assisted backwashing (NBB), is presented in this paper. Nanobubbles generated in this study had an average diameter of about 150 nm, and some of the nanobubbles could pass through the pores of microfiltration (MF) membranes used for MBRs. Therefore, nanobubbles introduced from the permeate side during backwashing might exhibit cleaning effects for membranes since applications of nanobubbles for cleaning of various materials such as protein-coated gold electrodes and stainless steel have been reported. The effectiveness of NBB was compared with that of tap water backwashing (TWB) and chemically enhanced backwashing (CEB) using 50 ppm NaClO. Experiments were carried out by using three bench-scale MBRs installed at a local wastewater treatment plant. The three MBRs were operated in parallel with identical operating conditions except for backwashing conditions. Polyethylene glycol (PEG) granular materials were inserted in each membrane tank to scour the membrane surface. Regardless of the variation of the feed, NBB always exhibited better cleaning performance than TWB, and the cleaning efficiency of NBB was sometimes comparable to that of CEB. The degree of reversible fouling observed with TWB was 424 % higher than that with NBB, indicating that NBB is much more effective than TWB for the control of reversible fouling. It was also found that NBB could mitigate irreversible fouling even in the absence of a thick protective layer on the surface of the membrane. It was attempted to reveal the mechanism by which NBB enhances the cleaning effect by carrying out comprehensive analysis of the distribution of filtration resistance, mixed liquor suspension and the fouling layer. Significant changes in microbial activity of the mixed liquor suspension and sludge properties in the MBRs were not observed when NBB was carried out. The results of the analysis suggested that NBB made the structure of the fouling layer more porous, possibly facilitating the removal of the fouling layer from the membrane.

New insight into the irreversible membrane fouling in different pore-sized ultrafiltration ceramic membrane bioreactors (UCMBRs) for high-strength textile wastewater treatment

Despite great achievements in ceramic membrane bioreactor applications, membrane fouling, which decreases the permeability and separation performance of bioreactors and is associated with increased operational costs and energy consumption, remains a problem. The aim of this study was to expand our understanding of the fouling behavior in the long-term performance of ultrafiltration ceramic membrane bioreactors (UCMBRs) for high-strength textile wastewater reclamation. Using real textile wastewater effluent, the effects of ultrafiltration (UF) membrane pore sizes, cleaning strategies, and foulant distribution were systematically evaluated over more than three months of continuous operation. The results showed that UCMBR system achieved chemical oxygen demand and total nitrogen removal efficiencies as high as 91–95% and 39–43%, respectively. The high PN concentration can easily increase the viscosity of mixed liquor samples, contributing to a fouling layer on the membrane surface. In addition, the fouling layer formed on the surface of small-pore-sized ceramic UF membranes was not completely reversible but was difficult to eliminate by simple physical cleaning. Soluble extracellular polymeric substances, especially proteins and low molecular weight neutrals, remained, resulting in irreversible fouling on the UF membrane. However, saturated CO2 backwash showed great potential for enhancing the system through efficient fouling control without using environmentally unfriendly cleaning chemicals. The cake-intermediate and complete-standard models were suitable for explaining the fouling mechanism in the large- and small-pore-sized UF membranes, respectively.

Superhydrophilic micro/nano hierarchical functionalized-CuO/PVDF nanocomposite membranes with ultra-low fouling/biofouling performance for acetate wastewater treatment: MBR application

In membrane bioreactor (MBR) application, there are considerably influencing factors on membrane performance over time making serious problems, including reduced permeation flux and rejection percentage as well as formed thick fouling/biofouling layer. This study provided a new preparation strategy to fabricate extraordinary superhydrophilic CuO/PVDF nanocomposite membranes with micro/nano hierarchical structure, using a wet micro-pattern casting knife with simultaneous bombardment of hydrophilic CuO nanoparticles/non-solvent solution via cold spray coating (s-NIPs method). When compared to the neat membrane, the main characteristics of the superhydrophilic membrane enhanced such as surface area (70%) and pure water flux (PWF) (400%). Protein rejection (PR) and chemical oxygen demand (COD) removal were also obtained as about 96.7% and 97.8% at constant mixed liquor suspended solids (MLSS = 6000 mg/l) in a submerged aerobic MBR, fed by the synthesized sodium acetate wastewater (compared to the neat case: 78% and 91%), respectively. Furthermore, its excellent antifouling/biofouling properties were proved via significantly less formation of biofilm and adherence of extracellular polymeric substances (EPSs) and soluble microbial products (SMPs) on the membrane surface. Low variation of sludge flux and COD removal by increasing MLSS from 6000 (348 LMH and 96.7%) to 12000 mg/L (200 LMH and 94.2%) proved the significant impact of the preparation method on the membrane performance. Stability of the F–CuO coated layer caused superhydrophilicity and antibacterial properties to be maintained under long-period. The obtained results demonstrated potential of the fast, facile, simple, and one-step preparation method without compromising the membrane separation ability, while simultaneously providing superhydrophilicity, antibacterial activity, and ultra-low fouling/biofouling formation.

Low-maintenance anti-fouling and phosphorus removal of an electro-MBR with Fe anode-cathodic membrane

Frequent membrane cleaning and chemical phosphorus removal increase the maintenance burden of membrane bioreactors (MBRs), greatly limiting their application in decentralized wastewater treatment. Herein, an electrochemical MBR (electro-MBR) integrating a Fe anode and a membrane cathode was constructed to simultaneously alleviate membrane fouling and enhance phosphorus removal using a low-maintenance method. Compared with conventional MBR, coagulation by Fe ions released from the sacrificial anode coupled with electrostatic repulsion from the cathodic membrane significantly mitigated membrane fouling in the electro-MBR. The coagulation significantly increased the sludge floc size, favoring the generation of a porous cake layer, and enhanced phosphorus removal by 69.0% without the addition of chemicals. The electrostatic repulsion impeded the adhesion of foulants, particularly extracellular polymeric substances (EPS), onto the conductive membrane. The EPS deposited onto the membrane surface declined by 31.5% under the synergistic effect of coagulation and electrostatic repulsion. Additionally, the applied electric fields increased microbial species diversity and enhanced the adaptability of biochemical systems to water quality variations. The service life of the membrane module in the electro-MBR was extended by 3 times, and the dosing coagulant was replaced by a sacrificial Fe anode with a working life of 600 d, resulting in 66.7% decrease in maintenance costs. This study suggests a low-maintenance method to achieve anti-fouling and phosphorus removal and promotes the development and application of MBRs.

Continuous-flow membrane bioreactor enhances enrichment and culture of autotrophic nitrifying bacteria by removing extracellular free organic carbon.

An activated sludge system can be inoculated with enriched nitrifying bacteria to enhance NH4+-N removal, or enriched nitrifying bacteria can be added directly to a river to remove NH4+-N. However, the enrichment culture is still generally inefficient and the technical bottleneck has not been clarified. Previous studies have shown that extracellular free organic carbon (EFOC) inhibits the growth of some autotrophic bacteria, and separating EFOC during culture with a membrane bioreactor (MBR) promotes the continuous growth of autotrophic bacteria and CO2 fixation. However, whether a membrane bioreactor can also be used to enrich and culture autotrophic nitrifying bacteria by separating EFOC has not been verified. In this study, an MBR was constructed to separate EFOC during the culture of nitrifying bacteria in activated sludge to confirm that the MBR better enriches and cultures nitrifying bacteria than a sequencing batch reactor (SBR). Our results showed that after culture for 34days, the rate of NH4+-N removal and the nitrification rate by nitrifying bacteria in the MBR were 2.20-fold and 1.42-fold higher than in the SBR, respectively. The abundance of Nitrospira in the MBR was also 7.23-fold greater than in the SBR at the end of the experimental period. After 34days, the average concentration of EFOC and the average EFOC/bacterial organic carbon ratio in the MBR were only 53% and 37% of those in the SBR, respectively. A correlation analysis suggested that the timely removal by the MBR of the EFOC generated during the culture process may be an important factor in promoting the growth of autotrophic nitrifying bacteria. The possible mechanism by which the MBR separates EFOC to the growth of promote autotrophic nitrifying bacteria is discussed from the perspective of the inhibitory effect of EFOC on cbb gene transcription. Our experimental results suggest a new approach to enhancing the enrichment of autotrophic nitrifying bacteria and extending the application of MBRs.

Feasibility of hydrophilic polyethylene separator for membrane bioreactor for wastewater treatment: Fouling behaviors and cleaning

The increasing cost of polyvinylidene fluoride has motivated efforts of researchers to seek a cheap membrane material for membrane bioreactors (MBRs). An inexpensive hydrophilic polyethylene (PE) lithium-ion battery separator was used in this study to construct a flat-sheet membrane module for MBRs treating synthetic municipal wastewater (PE-MBR). The PE separator showed an interconnected and open pore structure with a pore size of 50–60 ​nm. Its hydrophilicity was confirmed by the contact angle (77.65°) and relatively high pure water permeability of 412.17 LMH. The operation of the PE-MBR under 15 LMH below the critical flux last more than 50 ​d before the trans-membrane pressure reached 25 ​kPa and the COD removal was higher than 90%. The revised Hermia model fitting suggested that cake formation was the predominant fouling mechanism on the PE separator with polysaccharides as the main organic pollutant. A cleaning efficiency of 76.26% of the PE separator was achieved using 1 ​g/L of Oxalic acid, 3 ​g/L of NaOH, and 100 ​mg/L of EDTA as the cleaning reagents. This study establishes the feasibility of the PE separator in MBRs and provides a new strategy to lower the operation cost and broaden the real applications of MBR in wastewater treatment.

High performance antibiofouling hollow fiber polyethersulfone nanocomposite membranes incorporated with novel surface-modified silver nanoparticles suitable for membrane bioreactor application

Surface-modified silver nanoparticles with amine, thiol, carboxyl, and the thiol-polyvinylpyrroldidone (PVP) functional groups were synthesized as functional filler for nanocomposite membranes for membrane bioreactor (MBR), with the aims to enhance antimicrobial effect of silver, while immobilizing silver nanoparticles inside the matrix of the membrane. Analyses by fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), and dynamic light scattering (DLS) proved successful surface modification for each type of nanoparticles, with average particle sizes of 69, 20, 33, and 34 nm for amine, carboxyl, thiol and thiol-PVP modified silver nanoparticles, respectively. Polyethersulfone (PES) based nanocomposite hollow fiber membranes showed different morphology and performance in ultrafiltration and MBR experiments. The surface modifications were able to immobilize silver nanoparticles inside the membrane by providing proper interactions between the nanoparticles and polymer, reducing silver release compared to the unmodified nanoparticles. Modified nanoparticles changed the phase inversion, resulting in different morphology and average pore size in the range of 7.6–28.0 nm. The surface-modified nanoparticles with enhanced antimicrobial activity improved antifouling properties of the nanocomposite membranes, leading to interesting MBR performance improvements, with 122 % increase of flux, 23 % increase of chemical oxygen demand (COD) removal and flux recovery by over 30 %.

Using an innovative umbrella-shape membrane module to improve MBR for PN-ANAMMOX process.

Membrane fouling has been a key factor limiting the applications of membrane bioreactor (MBR). In this study, a novel umbrella-shape membrane module was applied to construct two MBRs for two-stage partial nitrification-anaerobic ammonia oxidation (PN-ANAMMOX) process. After 55days operation, the ANAMMOX process was started and the PN process was well controlled. Then, the ANAMMOX and PN process were successfully coupled to run the PN-ANAMMOX process. On 103days, the best nitrogen removing effect was achieved with the maximum nitrogen loading rate (NLR) of 0.4kgN·(m3·d)-1 and the corresponding maximum total nitrogen removal rate (TNRR) of 75.23%.The umbrella-shape membrane module in both reactors only needed to be cleaned once during the operation for 105days, indicating that the membrane module had better resistance to membrane fouling. The functional bacteria were cultivated in suspension state; moreover, the cell densities of ammonia oxidizing bacteria (AOB) and ANAMMOX bacteria (AnAOB) reached 58.32 × 1012 copies/g sludge and 28.39 × 1012 copies/g sludge. Their abundances reached 73.25% and 57.80% of the total bacteria, respectively. MBR improved by umbrella-shape membrane module could realize the rapid start-up of ANAMMOX process, effective control of PN process, and stable operation of PN-ANAMMOX process. This study provided a novel approach to control membrane fouling by optimizing the membrane module shape and widened applications of MBRs in PN-ANAMMOX process.