Membrane Molecular Weight Research Articles

Effect of the membrane processing on tannin removal from soluble fraction of Persian gum

SummaryTannins, which are known as anti‐nutrient compounds with capability of limiting proteins and minerals bioavailability, are present in Persian gum. Ultrafiltration (UF, polysulfone membrane, 30 and 90 kDa, 1, 2 and 5 bar) and nanofiltration (NF, polysulfone, 400 Da, 2.5 and 5 bar) were used to remove tannin from the soluble fraction of Persian gum. The results revealed that the highest amount of tannin removal was achieved in UF (5 bar) and NF (5 bar). However, the use of the membrane process significantly decreased the apparent viscosity of the permeate, which might have an undesirable effect on the functionality of the gum. The effects of membrane molecular weight cut‐off, feed temperature, ultrasound pre‐treatment, feed concentration and pH, on the amount of tannic acid reduction, and changes in permeate flux, volume concentration factor difference, tannin reduction efficiency, and permeate apparent viscosity were evaluated. The results showed that total tannin removal efficiency was increased by ultrasound pre‐treatment, reduction of feed pH, and higher membrane molecular weight cut‐off. Increasing the feed temperature and concentration enhanced the apparent viscosity of permeate, although its value was lower than the control sample.

Sodium lignosulfonate as an extracting agent of methylene blue dye using a polymer-enhanced ultrafiltration technique

The purpose of this research was to evaluate the efficacy of sodium lignosulfonate (LS) as a dye adsorbent in the removal of methylene blue (MB) from water by polymer-enhanced ultrafiltration. Various parameters were evaluated, such as membrane molecular weight cut-off, pH, LS dose, MB concentration, applied pressure, and the effect of interfering ions. The results showed that the use of LS generated a significant increase in MB removal, reaching an elimination of up to 98.0 % with 50.0 mg LS and 100 mg L−1 MB. The maximum MB removal capacity was 21 g g−1 using the enrichment method. In addition, LS was reusable for up to four consecutive cycles of dye removal-elution. The removal test in a simulated liquid industrial waste from the textile industry was also effective, with a MB removal of 97.2 %. These findings indicate that LS is highly effective in removing high concentrations of MB dye, suggesting new prospects for its application in water treatment processes.

Compositional Consequences of Ultrafiltration Treatment of White and Red Wines.

Clarification and stabilisation processes are routinely performed post-fermentation to 'finish' wines, but traditional methods are slow and energy intensive, create waste, and can affect wine volume and quality. New methods that 'finish' wine rapidly, with higher recovery rates, and reduced waste and input costs, are therefore needed. Ultrafiltration is a separation process that fractionates liquids, nominally, according to molecular weight. By comparing the composition of permeate and retentate derived from pilot-scale fractionation of white and red wine using 75, 20, or 10 kDa membranes and different degrees of permeation (50, 80, 90, or 95%), this study sought to evaluate ultrafiltration as an innovative approach to the clarification and stabilisation of wine. Mass balance analysis confirmed that titratable acidity and alcohol were fractionated according to the degree of permeation; however, proteins, polysaccharides, and phenolic compounds (including anthocyanins for red wine) were concentrated in retentate due both to the membrane molecular weight cut-off (MWCO) specifications and degree of permeation. The retention of wine constituents smaller than the nominal MWCO suggests that interaction with other macromolecules or the membrane surface occurred. Red wine permeates were stripped of much of their essential character and were no longer considered commercially acceptable. In contrast, the removal of protein and phenolic compounds from white wine demonstrated the potential for ultrafiltration to remediate heat unstable or excessively phenolic wines. Findings enabled the identification of other winemaking applications of ultrafiltration technology that could enhance wine quality, process efficiency, and profitability.

Lignin Purification from Mild Alkaline Sugarcane Extract via Membrane Filtration

In this study, the separation of lignin from a mild alkaline sugarcane bagasse extract was studied, and the impacts of different parameters on the filtration performance were evaluated. The tested parameters included transmembrane pressure (0.5–3.0 bar), shear rates (2831–22,696 s−1), temperature (20 and 40 °C), membrane molecular weight cut-off (5 and 10 kDa), and membrane material (polyethersulfone and polysulfone). During the filtration process, the permeate flux and all the main components of the extract were analyzed, including lignins (acid insoluble lignin and acid soluble lignin), sugars (xylose, arabinose, glucose, and galactose), total phenolic compounds, and phenolic acids (p-coumaric acid, ferulic acid, vanillin, and 4-hydroxybenzaldehyde). It was proved that the tested conditions had a great impact on the permeate flux and molecule retention rate. Increasing the temperature from 20 to 40 °C resulted in a much higher permeate flux for the 5 kDa PES membrane, and the impact of shear rate was greater at 40 °C for this membrane. Although the 5 kDa PES membrane could retain slightly more large molecules, i.e., acid-insoluble lignin and xylose, the 10 kDa membrane afforded greater phenolic acid removal capacity, leading to higher purity. For the 10 kDa PS membrane, the polarization layer began to form at TMP below 0.5 bar. This membrane had a lower retention rate for all molecules than the 10 kDa PES membrane.

Physicochemical properties and stability of milk permeate as influenced by ultrafiltration processing parameters

The objective of this study was to determine the effect of membrane molecular weight cut-off (5 and 10 kDa), and filtration temperature (25, 15 and 10 °C) on the physicochemical properties of milk permeate (MP). Although MPs produced had a similar gross chemical composition, MP produced with the 10 kDa membrane at 25 °C had the lowest pH (6.64) and ionic calcium content (2.33 mm), while MP produced with the 5 kDa membrane at 10 °C had the highest levels of 6.82 and 2.85 mm for pH and ionic calcium, respectively. Incubation of MPs at 60 °C resulted in precipitation, with MPs produced with the 10 kDa membrane having larger, less soluble and thermodynamically more stable particles than MPs produced with the 5 kDa membrane. These results demonstrate that filtration parameters significantly affected the physicochemical properties of MPs, with implications for downstream processing.

Efficient synthesis of high-purity carbon dots via self-polymerization driven bottom-up growth for high-selectivity sensing and high-efficiency separation

Carbon dots (CDs) have attracted extensive interest due to their exceptional optical properties and facile synthesis processes. However, achieving high-efficiency synthesis of high-purity CDs with high yield remains an unresolved critical issue. Herein, we report a facile and versatile self-polymerization-driven bottom-up growth strategy for efficient fabrication of high-purity CDs. As a proof-of-concept demonstration, dopamine and its four analogues were used as the self-polymerizable precursors for self-driven synthesis of fluorescent CDs with high-purity. By employing a mixed-solvent system and rationally regulating periodate oxidation process, the highly controllable self-polymerization processes and efficient solvothermal-assisted production of polydopamine and polyphenols derived CDs were readily achieved. Further integrating high molecular weight membrane dialysis, we successfully obtained the highly purified polydopamine-derived CDs with high yield of 21.1 % and quantum yield of 3.6 %, confirmed by nuclear magnetic resonance, capillary electrophoresis and other types of high-resolution characterization techniques. The formation and luminescence mechanisms of the self-polymerized CDs were also elucidated through comparative analysis of their morphological features and elemental compositions. We also demonstrated the broad universality of this self-polymerization driven bottom-up strategy by utilizing by employing four other phenolic compounds, including l-dopa, gallic acid, catechol, and pyrogallol, as readily accessible precursors for high-yield synthesizing highly purified fluorescent CDs. Moreover, the enormous application potential of the high-purity CDs for high-selectivity sensing and high-efficiency electrochromatographic separation was thoroughly demonstrated.

Mathematical and statistical modeling of glucose permeation through ultrafiltration system

Membrane bioreactors (MBRs) have been recently proposed for enhancing enzymatic hydrolysis of lignocelluloses by simultaneously and selectively removing the produced sugars from the reaction system. An inverted dead-end MBR with polyethersulfone membrane was used to investigate glucose permeation. The effects of glucose concentration, water flowrate, and membrane molecular weight cut-offs (MWCO), were investigated. The developed diffusion-convective model predicted glucose permeation with R2 value of 0.96. The statistical analysis showed that the effects of glucose concentration and water flowrate were significant, with P-value less than 0.05 for both, whereas that of the MWCO was insignificant (P-value of 0.66). This is the first attempt to mathematically describe the behavior of glucose across ultrafiltration membrane, while taking into consideration both molecular diffusion and convective flow. The findings of this work are essential for understanding the behavior and enhancing the performance of solute permeation through ultrafiltration membrane, which is the heart of many processes.

Retention of nine micropollutants covering a wide range of physical-chemical properties using polyelectrolyte multilayer hollow fiber NF membranes

Our work investigates the efficiency of two polyelectrolyte multilayer hollow fiber nanofiltration (NF) membranes for the removal of nine micropollutants (MPs) from pre-treated wastewater. The Square Latin method was used to select the contaminants to study according to their molecular weight, hydrophilicity (log Kow), and charge at environmental pH. NF experiments were carried out in batch mode at 20 °C with a crossflow velocity of 1 m.s−1, and a transmembrane pressure of 3 bar. Retentions of MPs and salts were evaluated at various volume reduction ratios (1, 3 or 6), membrane molecular weight cut-off (400 or 800 Da) and fouling potential of the matrix (ultrapure water, synthetic water, or real pre-treated wastewater). Our study identified the 400 Da membrane as the best option as balance between MPs and salts retention was the most acceptable. With this membrane, two thirds of the investigated MPs showed a retention above 90 %, two MPs had a retention around 60 % and only one MP was retained less than 20 % while monovalent salts had a retention lower than 30 %. Our work identified size exclusion and electrostatic interactions as the main mechanisms involved in MPs retention by the negatively charged membrane. This membrane showed its efficiency to maintain high permeation flux during 24 h-filtration of stream with organic matter content comparable to secondary-treated wastewater to a volume reduction ratio up to 6. At this content, organic matter did not modify retention of micropollutants or salts. The selected membrane is an encouraging tool to produce MPs-free water from pre-treated wastewater without producing a highly saline retentate. In the future, permeate would possibly be employed for REUSE purposes.

Ultrafiltration and Nanofiltration for the Removal of Pharmaceutically Active Compounds from Water: The Effect of Operating Pressure on Electrostatic Solute-Membrane Interactions.

The present work investigates nanofiltration (NF) and ultrafiltration (UF) for the removal of three widely used pharmaceutically active compounds (PhACs), namely atenolol, sulfamethoxazole, and rosuvastatin. Four membranes, two polyamide NF membranes (NF90 and NF270) and two polyethersulfone UF membranes (XT and ST), were evaluated in terms of productivity (permeate flux) and selectivity (rejection of PhACs) at pressures from 2 to 8 bar. Although the UF membranes have a much higher molecular weight cut-off (1000 and 10,000 Da), when compared to the molecular weight of the PhACs (253-482 Da), moderate rejections were observed. For UF, rejections were dependent on the molecular weight and charge of the PhACs, membrane molecular weight cut-off (MWCO), and operating pressure, demonstrating that electrostatic interactions play an important role in the removal of PhACs, especially at low operating pressures. On the other hand, both NF membranes displayed high rejections for all PhACs studied (75-98%). Hence, considering the optimal operating conditions, the NF270 membrane (MWCO = 400 Da) presented the best performance, achieving permeate fluxes of about 100 kg h-1 m-2 and rejections above 80% at a pressure of 8 bar, that is, a productivity of about twice that of the NF90 membrane (MWCO = 200 Da). Therefore, NF270 was the most suitable membrane for this application, although the tight UF membranes under low operating pressures displayed satisfactory results.

Use of ultrafiltration/diafiltration for the processing of antisense oligonucleotides.

Ultrafiltration/diafiltration (UF/DF) has been the hallmark for concentrating and buffer exchange of protein and peptide-based therapeutics for years. Here we examine the capabilities and limitations of UF/DF membranes to process oligonucleotides using antisense oligonucleotides (ASOs) as a model. Using a 3 kDa UF/DF membrane, oligonucleotides as small as 6 kDa are shown to have low sieving coefficients (<0.008) and thus can be concentrated to high concentrations (≤200 mg/mL) with high yield (≥95%) and low viscosity (<15 centipoise), provided the oligonucleotide is designed not to undergo self-hybridization. In general, the oligonucleotide should be at least twice the reported membrane molecular weight cutoff for robust retention. Regarding diafiltration, results show that a small amount of salt is necessary to maintain adequate flux at concentrations exceeding about 40 mg/mL. Removal of salts along with residual solvents and small molecule process-related impurities can be robust provided they are not positively charged as the interaction with the oligonucleotide can prevent passage through the membrane, even for common divalent cations such as calcium or magnesium. Overall, UF/DF is a valuable tool to utilize in oligonucleotide processing, especially as a final drug substance formulation step that enables a liquid active pharmaceutical ingredient.

The Application of Polyethersulfone Ultrafiltration Membranes for Separation of Car Wash Wastewaters: Experiments and Modelling.

The wastewater generated as a result of car washes is considered a new source of water. However, recovered water must meet the required quality criteria for reuse. For this purpose, the ultrafiltration (UF) process can be successfully used. The main aim of the present work was to investigate the influence of the membrane's molecular weight cut-off (MWCO) on the UF performance in terms of the fouling phenomenon and retention degree of car wash wastewater. Moreover, for a better understanding of the fouling mechanisms, Hermia's model was used. The experimental studies were conducted with the use of two polyethersulfone (PES) membranes (MWCO of 10 kDa and 100 kDa). It has been noted that the used membranes provided a high-quality permeate and excellent turbidity removal, up to 99%. Moreover, it has been noted that the MWCO membrane has a significant impact on the fouling mechanism. Generally, a much greater intensity of fouling for the membrane with MWCO of 100 kDa was observed. Results obtained in the present study showed that both real wastewaters and the clean solutions used for washing cars cause the fouling phenomenon. It has been proven that rinsing the membranes with water is not sufficient to recover the initial membrane's performance. Hence, periodic chemical cleaning of the membranes was required. Fitting the experimental data to Hermia's model allowed us to indicate that membranes with MWCO of 100 kDa are more prone to intermediate blocking. To sum up, the findings suggest that for the UF of the car wash wastewater, the use of membranes with MWCO equal to 10 kDa is recommended.

Microwave-assisted design of nanoporous graphene membrane for ultrafast and switchable organic solvent nanofiltration

Layered two-dimensional materials can potentially be utilized for organic solvent nanofiltration (OSN) membrane fabrication owing to their precise molecular sieving by the interlayer structure and excellent stability in harsh conditions. Nevertheless, the extensive tortuosity of nanochannels and bulky solvent molecules impede rapid permeability. Herein, nanoporous graphene (NG) with a high density of sp2 carbon domain was synthesized via sequential thermal pore activation of graphene oxide (GO) and microwave-assisted reduction. Due to the smooth sp2 carbon domain surfaces and dense nanopores, the microwave-treated nanoporous graphene membrane exhibited ultrafast organic solvent permeance (e.g., IPA: 2278 LMH/bar) with excellent stability under practical cross-flow conditions. Furthermore, the membrane molecular weight cut-off (MWCO) is switchable from 500 Da size of molecule to sub-nanometer-size molecules depending on the solvent type, and this switching occurs spontaneously with solvent change. These properties indicate feasibility of multiple (both binary and ternary) organic mixture separation using a single membrane. The nanochannel structure effect on solvent transport is also investigated using computation calculations.

Membrane Technology as a Strategy for Improving β-Galactosidase Concentration Processes: The Influence of the pH, Membrane Molecular Weight, Pressure, and Ionic Strength in the Process

The enzyme β-galactosidase catalyzes the hydrolysis of lactose into glucose and galactose, although for its effective application it is necessary to establish techniques for purification, concentration, or polishing, such as membrane separation processes, in particular ultrafiltration. The present study aimed to investigate ultrafiltration and diafiltration applied as initial steps for concentration and salt removal, respectively, in the β-galactosidase purification processes. Additionally, the influence levels of the pH (6.5, 7.7, or 7.5), membrane molecular weight cut-off (30, 50, 60, or 100 kDa), operating pressure (1.5, 2.0, or 2.5 kgf/cm2), and ionic strength of the ultrafiltration using NaCL or KCl (0.01–0.1 M) were evaluated considering the enzyme recovery, purification, retention, and concentration factors in relation to the proteins, volume, activity, and protein flux and yield of the processes. The ultrafiltration of the crude enzyme extract at pH 7.5 and 1.5 kgf/cm2 with a 50 kDa polyethersulfone membrane resulted in a volume concentration of the β-galactosidase extract up to 7.1-fold greater, a purification factor 1.2-fold greater, and an enzyme recovery rate of 108.9% by eliminating metabolites during the purification process. In addition, the lowest flux variation range (16.0 to 13.1 L/m2·h) was observed under these same conditions, thereby representing a decrease of 18.0%. An increase in the operating pressure and the addition of salts results in reduced enzyme recovery (up to 38% of the process yield (734.1 to 453.7 U/h) and up to 40% of the enzyme recovery rate (108.9 to 60.6%) during the ultrafiltration using NaCl, respectively). The operation in the diafiltration mode allowed salt removal after the purification of β-galactosidase (enzymatic recovery rates above 93.4%) via precipitation and ion-exchange chromatography elution and as part of an aqueous two-phase system using 6 diafiltration cycles, thereby revealing its application potential.

On the edge between organic solvent nanofiltration and ultrafiltration: Characterization of regenerated cellulose membrane with aspect on dendrimer purification and recycling

The performance of commercial cellulose membranes with pore size on the border between ultra- and nanofiltration in selected organic solvents was studied focusing on rejection of small solutes and applicability for dendrimer purification. Organic markers in the MW range 100 – 700 Da and polarity range from nonpolar to polar protic compounds (aliphatics, aromatics, ethers, esters and alcohols) were used for membrane characterization. Transmission experiments in mixtures of methanol and dichloromethane of variable ratio showed the suitability of tested membranes for intended purpose, bringing information on structural factors affecting the rejection. Besides solute molar volume, its polarity type, or affinity, most conveniently expressed by Hansen solubility parameters, was found to be a crucial factor; with increasing size of solute molecule the spatial arrangement becomes also important. Solvent composition influences not only the behavior of solutes, but it also affects the membrane structure: poor solvation of cellulose by less polar solvents causes partial pore collapse, resulting in a decrease of membrane molecular weight cutoff. This effect can be used to improve the retention of a target product, as was shown for the first generation amphiphilic dendron. In addition, a simple mathematical model, allowing to estimate the course of nanofiltration and to optimize its conditions in a semicontinuous dead-end setup, is presented.

Fractionation by ultrafiltration of an aqueous extract of chestnut obtained by pressurized hot water extraction

Different types, ceramic and polyethersulfone, ultrafiltration membranes were evaluated to purify a wood extract obtained in pressurized hot water conditions. Tests were performed at transmembrane pressure (TMP) from 0.4 to 2.0 bars with membrane molecular weight cut-offs ranging from 5 kDa to 100 kDa. The results showed the permeate fluxes were lower than 15 L.h-1.m-², except for the 100 kDa organic membrane, with no influence of the feed flowrate. The retention of total phenolic compounds highly depends on the membrane cut-off but the retention rates of gallic and ellagic acid were not directly link to the cut-off. The retention rate of gallic acid is lower than 10%, when ellagic acid had retention ranging from 75 to 95 % for the membrane 5 kDa. It is suggested that other phenomena could be involved in solute retention, i.e. Donnan effect or solubility, that could explain so large differences.

Prediction of organic contaminant rejection by nanofiltration and reverse osmosis membranes using interpretable machine learning models.

Efficiency improvement in contaminant removal by nanofiltration (NF) and reverse osmosis (RO) membranes is a multidimensional process involving membrane material selection and experimental condition optimization. It is unrealistic to explore the contributions of diverse influencing factors to the removal rate by trial-and-error experimentation. However, the advanced machine learning (ML) method is a powerful tool to simulate this complex decision-making process. Here, 4 traditional learning algorithms (MLR, SVM, ANN, kNN) and 4 ensemble learning algorithms (RF, GBDT, XGBoost, LightGBM) were applied to predict the removal efficiency of contaminants. Results reported here demonstrate that ensemble models showed significantly better predictive performance than traditional models. More importantly, this study achieved a compelling tradeoff between accuracy and interpretability for ensemble models with an effective model interpretation approach, which revealed the mutual interaction mechanism between the membrane material, contaminants and experimental conditions in membrane separation. Additionally, feature selection was for the first time achieved based on the aforementioned model interpretation method to determine the most important variable influencing the contaminant removal rate. Ultimately, the four ensemble models retrained by the selected variables achieved distinguished prediction performance (R2adj = 92.4 %-99.5 %). MWCO (membrane molecular weight cut-off), McGowan volume of solute (V) and molecular weight (MW) of the compound were demonstrated to be the most important influencing factors in contaminant removal by the NF and RO processes. Overall, the proposed methods in this study can facilitate versatile complex decision-making processes in the environmental field, particularly in contaminant removal by advanced physicochemical separation processes.

Relationship between the Hansen solubility parameter and changes in membrane mass-transfer channels: A quantitative model

The relationship between swelling, the difference (Δδ) in theoretical Hansen solubility parameters (HSP) between the two substances, and the change of membrane mass-transfer channel has been controversial. In this work, a completely new parameter, Swell-Cavity Ratio (SCR), defined as the ratio of membrane molecular weight cut off (MWCO), was introduced to characterize the changes in mass transfer channels before and after membrane swelling. Models of the relationship between Δδ and SCR were successfully constructed for nanoporous glassy (SCR = 0.19 × Δδ0.40) and rubbery (SCR = 17.7 × Δδ-0.93) membranes, using the swelling as a bridge. Based on this contradiction in models, we speculate that SCR variation is strongly related to the separation mechanism of the membranes. The theoretical model accurately calculates the influence of the solvent on the membrane mass transfer channel, allowing for the selection of the best membrane material and pretreatment process to maximize treatment efficiency.

Cascaded membrane and chromatography technologies for fractionating and purifying of bovine milk oligosaccharides

We previously reported that major bovine milk oligosaccharides (BMO) can qualitatively and quantitatively analyzed using ultra high liquid chromatography on a high sensitivity fluorescence detection instrument; the method does not require the removal of lactose and uses small (only 100 μL) samples. In this study, we extended our strategy to fractionation and purification of BMO using membrane separation and chromatography techniques. The effects of membrane molecular weight cut-off (MWCO) and diafiltration the efficiency of the overall process were evaluated, with process optimization leading to suitable MWCOs for microfiltration (ceramic, 0.1 μm), ultrafiltration (spiral wound organic membrane, 30 kDa), and nanofiltration (spiral wound organic membrane, 500–700 Da). Total BMO recoveries of 97.36, 95.58, and 98.30% were observed for the microfiltration, ultrafiltration, and nanofiltration stages, respectively, with corresponding membrane fluxes of 75.74, 76.90, and 81.68 L/(m2·h), respectively. In addition, the crude BMOs were further purified using size-exclusion chromatography, activated charcoal, lactase digestion, dialysis, crystallization, and anion-exchange chromatography. Anion-exchange chromatography with Q Sepharose Fast Flow anion-exchange resin was found to be more suited to industrial BMO production than other methods; it not only effectively separates lactose and oligosaccharides, but also exhibits dynamic adsorption capacity of 1.20 mg BMOs/mL gel.

Nanocomposite Polymeric Membranes for Organic Micropollutant Removal: A Critical Review.

The prevalence of organic micropollutants (OMPs) and their persistence in water supplies have raised serious concerns for drinking water safety and public health. Conventional water treatment technologies, including adsorption and biological treatment, are known to be insufficient in treating OMPs and have demonstrated poor selectivity toward a wide range of OMPs. Pressure-driven membrane filtration has the potential to remove many OMPs detected in water with high selectivity as a membrane's molecular weight cutoff (MWCO), surface charge, and hydrophilicity can be easily tailored to a targeted OMP's size, charge and octanol-water partition coefficient (Kow). Over the past 10 years, polymeric (nano)composite microfiltration (MF), ultrafiltration (UF), and nanofiltration (NF) membranes have been extensively synthesized and studied for their ability to remove OMPs. This review discusses the fate and transport of emerging OMPs in water, an assessment of conventional membrane-based technologies (NF, reverse osmosis (RO), forward osmosis (FO), membrane distillation (MD) and UF membrane-based hybrid processes) for their removal, and a comparison to the state-of-the-art nanoenabled membranes with enhanced selectivity toward specific OMPs in water. Nanoenabled membranes for OMP treatment are further discussed with respect to their permeabilities, enhanced properties, limitations, and future improvements.

An innovative method for the fractionation and pretreatment of pig farm biogas slurry by ultrafiltration

Humic acids and macromolecular organics in pig farm wastewater can limit the efficacy of biochemical treatment and lead to high chroma. In this work, an ultrafiltration (UF) pretreatment method for building pig farm wastewater was developed. Key process parameters, such as the membrane molecular weight cutoff (MWCO), transmembrane pressure (TMP) and permeate reflux ratio, were explored and optimized. The membrane fouling was evaluated, and the UF permeate underwent sequencing batch reactor (SBR) biochemical treatment. The UF performance was appropriate at 100 kDa and 0.1 MPa. When the permeate reflux ratio was 200%, the UF time was shortened by half. After the UF permeate underwent SBR biochemical treatments, the effluent met the current discharge standards (GB18596-2001). The gas chromatography–mass spectrometry (GC–MS) results showed that UF pretreatment can reduce the concentration and types of organics in the SBR effluent. A new wastewater treatment and resource recovery method for building pig farms is provided.