The function and application of MBR membrane（mbr膜的作用和用途）MBR membrane, also known as membrane bio reactor, is a new type of wastewater treatment system that combines membrane separation technology with biological treatment technology. The following is an explanation from four aspects: principle of action, core functions, application areas, and technological advantages:
1、 Principle of action: Collaborative biodegradation and membrane separation
Biological treatment stage
After sewage enters the bioreactor, microorganisms decompose organic matter (such as COD, BOD) through metabolic processes and remove pollutants such as nitrogen and phosphorus. The system maintains a high concentration of activated sludge (8000-10000mg/L), which is 2-3 times higher than traditional processes, significantly improving treatment efficiency.
Membrane separation stage
Using microfiltration (MF) or ultrafiltration (UF) membrane components (such as PVDF hollow fiber membranes), solid-liquid separation is achieved through physical sieving:
Interception of pollutants: The membrane pore size is ≤ 0.1 μ m, which can intercept activated sludge, macromolecular organic matter, bacteria, and viruses, and the effluent turbidity is close to zero.
Alternative secondary sedimentation tank: No need for traditional sedimentation tanks, reducing land occupation and preventing sludge loss.
2、 Core Function: Deep Purification and Resource Reuse
Water quality improvement
The effluent SS (suspended solids) is almost zero, meeting the Class A standard of the “Pollutant Discharge Standards for Urban Sewage Treatment Plants”, and can be directly used in non drinking scenarios such as greening, flushing, and industrial circulating water.
The removal rate of pathogens (such as Escherichia coli) exceeds 99%, reducing public health risks.
Sludge reduction
By extending the sludge age (SRT>30 days), the remaining sludge production can be reduced by about 30%, and the cost of sludge disposal can be lowered.
Anti impact load
High sludge concentration enhances system stability and adapts to water quality fluctuations (such as industrial wastewater impact).
3、 Application area: Covering multiple scenario requirements
Urban sewage treatment
Treating domestic sewage with a water reuse rate of over 70% can alleviate water scarcity.
Typical case: The “NEWater” project in Singapore achieved a wastewater reuse rate of over 30% after MBR technology treatment.
Industrial wastewater treatment
Applicable industries: high concentration organic wastewater from chemical, pharmaceutical, food processing, and other industries.
Effect: COD removal rate ≥ 90%, meeting emission or reuse standards (such as cooling tower makeup water).
Special Scene
Rural sewage: decentralized treatment to achieve “zero discharge” or resource utilization.
Ship/offshore platform: Small footprint, high automation, and treated wastewater can be directly discharged or reused.
4、 Technical advantages: efficient and flexible at the same time
Small footprint
No need for a secondary sedimentation tank, compact equipment, suitable for land scarce areas such as city centers and scenic spots.
Modular design
Flexible expansion can be achieved by adding or removing membrane components to adapt to changes in water volume.
Energy efficiency
The integrated MBR has low energy consumption (such as suction water) and reduces operating costs by 10% -20% compared to traditional processes.
Summary
MBR membrane achieves deep purification and resource reuse of wastewater through the synergistic effect of biodegradation and membrane separation. It has the advantages of excellent effluent quality, land saving, and strong impact resistance, and is widely used in urban, industrial, and special scenario wastewater treatment. It is one of the key technologies for water resource recycling.
MBR膜即膜生物反应器(Membrane Bio-Reactor)，是膜分离技术与生物处理技术有机结合的新型废水处理系统。以下从作用原理、核心功能、应用领域及技术优势四方面展开说明：
一、作用原理：生物降解与膜分离协同
生物处理阶段
污水进入生物反应器后，微生物通过新陈代谢作用分解有机物(如COD、BOD)，并去除氮、磷等污染物。系统维持高活性污泥浓度(8000-10000mg/L)，是传统工艺的2-3倍，显著提升处理效率。
膜分离阶段
采用微滤(MF)或超滤(UF)膜组件(如PVDF材质中空纤维膜)，通过物理筛分实现固液分离：
截留污染物：膜孔径≤0.1μm，可拦截活性污泥、大分子有机物、细菌及病毒，出水浊度接近零。
替代二沉池：无需传统沉淀池，减少占地面积，并防止污泥流失。
二、核心功能：深度净化与资源回用
水质提升
出水SS(悬浮物)几乎为零，满足《城镇污水处理厂污染物排放标准》一级A标准，可直接用于绿化、冲厕、工业循环水等非饮用场景。
对病原体(如大肠杆菌)去除率超99%，降低公共卫生风险。
污泥减量
通过延长污泥龄(SRT>30天)，减少剩余污泥产量约30%，降低污泥处置成本。
抗冲击负荷
高污泥浓度增强系统稳定性，适应水质波动(如工业废水冲击)。
三、应用领域：覆盖多场景需求
城市污水处理
处理生活污水，出水回用率可达70%以上，缓解水资源短缺。
典型案例：新加坡“NEWater”项目，MBR技术处理后污水回用率超30%。
工业废水处理
适用行业：化工、制药、食品加工等高浓度有机废水。
效果：COD去除率≥90%，满足排放或回用标准(如冷却塔补水)。
特殊场景
农村污水：分散式处理，实现“零排放”或资源化。
船舶/海上平台：占地小、自动化高，处理后污水可直接排放或回用。
四、技术优势：高效与灵活兼备
占地面积小
无需二沉池，设备紧凑，适合用地紧张地区(如城市中心、景区)。
模块化设计
可通过增减膜组件灵活扩容，适应水量变化。
能源效率
一体式MBR能耗低(如抽吸出水)，运行成本较传统工艺降低10%-20%。
总结
MBR膜通过生物降解与膜分离的协同作用，实现污水深度净化与资源回用，兼具出水水质优、占地省、抗冲击强等优势，广泛应用于城市、工业及特殊场景污水处理，是水资源循环利用的关键技术之一。
