1. technical name

Efficient and energy-saving membrane scrubbing technology and equipment for membrane bioreactor systems.

2. scope of application

MBR membrane modules for large and medium-sized sewage treatment plants.

3. technical content

3.1 technical principle

The high-efficiency and energy-saving membrane scrubbing technology of the MBR system converts the continuous air flow into a pulsed/intermittent air flow through pure hydraulic components without moving parts. After accumulating a certain amount of air, it is released in a very short time, thereby forming a high-intensity scrubbing air flow. Form shear scouring on the surface of the membrane wire to maintain a stable operating flux of the membrane system. The aeration box is made of non-metallic ABS material and is injection molded, with a compact internal structure. The volume of a single aeration box chamber is about 1.7×10-3m3, and the scrubbing air flow is 30 to 40 bubbles per minute. The specific process includes: (1) supplying a small non-directional continuous gas into the gas accumulation chamber. (2) Exhaust pressurized gas from the gas accumulation chamber to release the pressurized pulsed gas flow. (3) Repeatedly accumulate gas in the gas accumulation chamber.

3.2 main innovations

This technology can achieve periodic strong gas pulses through the uniquely designed hydraulic components of the aeration box to scour the membrane wires with high intensity. Compared with continuous gas scrubbing of perforated pipes, the air consumption is reduced by 40% to 60%. Compared with technologies such as "large and small gas periodic regulation scrubbing" and "large bubble continuous scrubbing", the air consumption is reduced by 10% to 20%. By utilizing the hydraulic structure of the aeration box, the actions of valves and equipment of other related technologies are not involved, reducing equipment investment and maintenance costs.

4. Pollution control or environmental restoration effects

In large and medium-sized MBR sewage treatment plants, membrane scrubbing air volume can be saved by 20% to 30%. With the same equipment investment, the operating stability of the MBR system can be significantly improved and the frequency of MBR membrane pollution cleaning can be reduced. The aeration box material is selected from ABS material injection molding, which has no secondary pollution to the environment.

5. Technology demonstration

This technology has been applied in MBR systems of 9 sewage treatment plants, with a corresponding treatment scale of more than 1.1 million m3/d, and the operation effect is good. Beijing Huaifang Reclaimed Water Plant adopted this technology in May 2018, June 2019, September 2020, and September 2021 respectively. At present, the membrane system is operating stably, the scrubbing air volume is reduced by 20% to 30% compared with before the transformation, the number of supporting fans in operation is reduced, and the system energy consumption is reduced. 6. investment estimation

Taking a 75,000 m3/d reclaimed water plant as an example, the investment in large-intensity, high-efficiency and energy-saving membrane scrubbing equipment for the MBR system is about 2.6 million yuan, with an annual economic benefit of 880,000 yuan, and an equipment life of 10 years.

7. investment recovery period

Taking a 75,000 m3/d reclaimed water plant as an example, the static investment payback period for equipment is about 3 years.

8. Prospects for transformation and promotion of technological achievements

This technology can be used for the upgrading of existing MBR systems, the application of MBR systems in new projects, and the technical upgrading of MBR manufacturers 'products. It is estimated that by 2025, the cumulative application scale will reach 10 million m3/d.