Breakthrough of MBR Replacing the Secondary Sedimentation Tank in Activated Sludge Process with Membrane Separation Technology

Membrane Bioreactor (MBR) technology, by integrating membrane separation technology with biological treatment, has successfully replaced the secondary sedimentation tank in the traditional activated sludge process, marking a significant breakthrough in the field of wastewater treatment. This innovation not only improves wastewater treatment efficiency but also significantly enhances effluent quality, bringing revolutionary changes to the water treatment industry.

I. Limitations of Traditional Secondary Sedimentation Tanks

Limited Separation Efficiency: Secondary sedimentation tanks rely on gravity settling, making it difficult to completely separate fine suspended solids and colloidal substances, leading to unstable effluent quality.

Large Footprint: Secondary sedimentation tanks require a large area, increasing the construction costs of wastewater treatment plants.

Poor Operational Stability: Secondary sedimentation tanks are prone to issues such as sludge bulking and floating, resulting in unstable operation.

Complex Sludge Recycle System: Secondary sedimentation tanks require a complex sludge recycle system, increasing operational management difficulties.

II. Breakthroughs of MBR Technology

MBR technology replaces the secondary sedimentation tank with membrane separation, addressing many issues of the traditional activated sludge process. Key breakthroughs include:

Efficient Solid-Liquid Separation: Membrane modules can effectively retain suspended solids, bacteria, and viruses, significantly improving effluent quality with near-zero suspended solids concentration.

Small Footprint: MBR systems integrate the biological reaction tank and membrane separation unit, eliminating the need for a secondary sedimentation tank and greatly reducing the footprint.

High Operational Stability: The membrane separation process is unaffected by sludge settling performance, avoiding issues like sludge bulking and floating, and ensuring more stable system operation.

Simplified Process Flow: MBR technology eliminates the secondary sedimentation tank and sludge recycle system, simplifying the process flow and reducing operational management complexity.

III. Technical Advantages and Application Value

High-Quality Effluent: MBR effluent quality surpasses traditional processes and can be directly reused for irrigation, landscape water, or industrial recycling.

Strong Adaptability: MBR technology can treat high-concentration, hard-to-degrade wastewater, making it suitable for various scenarios such as municipal, industrial, and rural wastewater treatment.

Energy Efficiency and Environmental Protection: MBR systems feature high automation, low energy consumption, and minimal chemical usage, aligning with green environmental principles.

Modular Design: MBR systems can be flexibly scaled according to treatment needs, adapting to different application requirements.

IV. Future Development Directions

Although MBR technology has made significant breakthroughs in replacing secondary sedimentation tanks, challenges such as membrane fouling and high operational costs remain. In the future, with advancements in membrane materials and intelligent management systems, MBR technology will achieve further breakthroughs in the following areas:

Reducing Membrane Fouling: Developing anti-fouling membrane materials and efficient cleaning technologies to extend membrane lifespan.

Lowering Operational Costs: Optimizing system design and operational parameters to further reduce energy consumption and maintenance costs.

Intelligent Management: Integrating IoT and big data technologies to enable intelligent operation and remote monitoring of MBR systems.

In conclusion, MBR technology, by replacing the secondary sedimentation tank with membrane separation, has achieved a major breakthrough in wastewater treatment processes. It provides an efficient, stable, and environmentally friendly solution for the water treatment industry, offering broad application prospects and significant social value.