Membrane Bio-Reactor (MBR) is a new type of wastewater treatment system that combines membrane separation technology and biological treatment technology.

The membrane module replaces the traditional biological treatment technology end of the secondary sedimentation tank, maintains a high concentration of activated sludge in the bioreactor, improves the organic load of biological treatment, thus reduces the footprint of wastewater treatment facilities, and reduces the amount of residual sludge by maintaining a low sludge load.

Membrane separation equipment is primarily utilized to retain activated sludge and macromolecular organic matter in the water. The concentration of activated sludge (MLSS) in the membrane bioreactor system can be increased to 8,000~10,000mg/L or even higher; the sludge age (SRT) can be extended to more than 30 days.

Membrane bioreactor because of its effective retention effect, can retain the generation cycle of microorganisms, can realize the depth of sewage purification, at the same time, nitrifying bacteria in the system can be fully reproduced, its nitrification effect is obvious, the depth of phosphorus denitrification to provide the possibility.

MBR product applications

Inlet and outlet water quality comparison:

Designed inlet water quality:

BOD5＜300mg/l      CODcr＜500mg/l    SS＜300mg/l T–N＜4-5mg/l

Outlet water quality:

BOD5＜5mg/l NH4+-N＜1.0mg/l   CODcr〈20mg/l   Turbidity＜1NTU

SS=0mg/l  Total number of bacteria＜20 pcs/ml

T-N＜5mg/l  E. coli not detected

MBR membrane technology first through the activated sludge to remove biodegradable organic pollutants in the water, and then use the membrane module to force the retention of activated sludge in the bioreactor and most of the suspended solids, to realize the solid-liquid separation of purified water and activated sludge, which strengthens the biochemical reaction, and improves the effect of wastewater treatment and effluent water quality.

Characteristics of the treatment process

(1) High efficiency, the effluent can be directly reused.

Due to the hollow fiber membrane on the biochemical reactor mixture has a highly efficient in separation, the process can be completely separated from the sludge and effluent, making the effluent SS and turbidity close to zero. At the same time, due to the loss of activated sludge is almost zero, so that the concentration of activated sludge in the biochemical reactor can be about 2-6 times higher than the traditional process, greatly improving the denitrification capacity.

(2) Stable operation, simple process,small floor space.

Due to the high concentration of activated sludge in MBR technology, the volume load of the device is large; good shock resistance to fluctuations in influent water. In addition to this process can greatly reduce the volume of biochemical reactor – aeration tank, so that the miniaturization of equipment and structures, no primary and secondary sedimentation tanks required, so that the system takes small spaces.

(3) Long sludge age and low residual sludge volume.

When the sludge concentration is high and the influent load is low, the nutrient to microorganism ratio (F/M) in the system is low and the sludge age becomes long. When the F/M is maintained at a low value, the growth of activated sludge is close to zero, which reduces the cost of treating the remaining sludge.

(4) Easy automatic operation and management.

As the membrane separation can make the activated sludge completely retained in the bioreactor, so that the hydraulic retention time (HRT) and sludge retention time (SRT) in the bioreactor are completely separate, so it can be flexibly and stably controlled; at the same time, it is very easy to realize the automatic control, and improve the automation level of sewage treatment.

Scope of Application for MBR

Membrane bioreactor is widely used in daily life sewage treatment and reuse for decentralized users such as living quarters, hotels, restaurants, resorts, schools, office buildings, etc. as well as organic sewage treatment for beer, tannery, food, chemical and other industries. The water produced by membrane bioreactor is often used for irrigation, washing, sanitation, landscaping and other non-drinking functions.

The domestic sewage treatment process is based on the utilization of sewage or the discharge requirements, and  natural purification capacity of the water to determine the treatment process of sewage treatment.

The treated water, whether used for industry, agriculture or recharge to replenish groundwater, must meet the relevant water quality standards.

Sewage Water Treatment Process

According to the depth of the treatment, it can be divided into primary, secondary and tertiary treatment processes.

Primary sewage treatment applies physical methods, such as sieving, filtration and sedimentation to remove undissolved suspended solids and floating substances from sewage.

Secondary treatment applies biological treatment methods, through the metabolic action of microorganisms to carry out the process of material transformation, the sewage in a variety of complex organic matter oxidation degradation into simple substances. Biological treatment of sewage water quality, water temperature, dissolved oxygen in the water, pH value, etc. have certain requirements.

Tertiary treatment of sewage is based on primary and secondary treatment, the application of coagulation, filtration, ion exchange, reverse osmosis and other physical and chemical methods to remove insoluble organic matter, phosphorus, nitrogen and other nutrients in sewage. The composition of pollutants in sewage is very complex, often requiring a combination of the above methods to meet the treatment requirements.

Sewage primary treatment is pre-treatment, secondary treatment is the main body of the treated sewage can generally meet the discharge standards. Tertiary treatment is the depth treatment, the effluent water quality is better, can reach the water quality standards for reuse.

Sewage Water Treatment Type

Depending on the amount of wastewater to be treated: Integrated wastewater treatment plant or a treatment plant using a steel mixed structure.