UASB Anaerobic Reactor Introduction
The UASB (Upflow Anaerobic Sludge Blanket) reactor is a high-efficiency Wastewater treatment equipment. With anaerobic granular sludge as the core medium, it decomposes organic pollutants in wastewater through microbial metabolism and is widely applied in high-concentration organic wastewater treatment.
The main body of the UASB reactor is a vertical steel tank equipped with a gas-solid-liquid three-phase separator at the upper part, and a suspended sludge layer and sludge bed at the lower part. Wastewater enters evenly from the bottom and makes full contact with anaerobic sludge for biochemical reaction. Organic matter is decomposed by anaerobic microorganisms into biogas, liquid and solid substances. The three-phase separator realizes efficient separation of gas, solid and liquid, with over 80% of organic matter converted into biogas to complete wastewater treatment. Customized design is available to optimize volumetric load, height-to-diameter ratio and other parameters according to enterprise wastewater characteristics, adapting to different treatment capacities.
Working Principle of UASB Anaerobic Reactor
Wastewater is pumped evenly into the sludge bed from the bottom of the reactor and fully contacts with anaerobic granular sludge. Under the action of anaerobic microorganisms, organic pollutants undergo three degradation stages: hydrolysis acidification, hydrogen-producing acetogenesis and methanogenesis, and are decomposed into biogas, water and a small amount of residual sludge. The mixed liquid rises to the three-phase separator, where biogas is collected and exported; sludge settles back into the reactor by gravity to participate in the reaction continuously; while the supernatant is discharged from the upper part, achieving dual goals of wastewater purification and biogas recovery.
Advantages of UASB Anaerobic Reactor
High treatment efficiency: The volumetric load reaches 3-10kgCODcr/m³·d, featuring high COD removal rate for high-concentration organic wastewater and stable effluent quality.
Low energy consumption & cost saving: Anaerobic reaction requires no aeration, consuming far less energy than aerobic processes. Meanwhile, biogas can be recycled as energy source to reduce operating costs.
Strong shock load resistance: Granular sludge features high activity and good sedimentation performance, adapting to fluctuations in water quality and flow with stable long-term operation.
Low sludge yield: The anaerobic process produces little excess sludge, lowering subsequent sludge treatment and disposal costs.
Small footprint & easy maintenance: Vertical tank design ensures compact structure. Equipped with automatic control system, it is simple to operate and maintain, suitable for centralized industrial wastewater treatment.
Application Fields of UASB Anaerobic Reactor
It is widely used for high, medium and low concentration organic wastewater treatment in industries such as papermaking, citric acid, food processing, brewing, starch production, alcohol production, landfill leachate, soybean product processing, biofuel, pharmaceutical and chemical industry. It is especially suitable for high-concentration wastewater such as alcohol and molasses wastewater, as well as medium and low-concentration wastewater from brewery, slaughterhouse and domestic Wastewater projects.
Process Flow of UASB Anaerobic Reactor
UASB Anaerobic Reactor Process Flow Chart
Pretreatment stage: Wastewater passes through grille and regulating tank to remove large particle impurities and balance water quality and volume, ensuring stable water inflow into the UASB reactor.
Anaerobic reaction stage: Wastewater is pumped into the bottom of the UASB reactor and enters the sludge bed for full contact with anaerobic granular sludge; organic matter is decomposed into biogas, water and sludge.
Three-phase separation stage: The mixed liquid rises to the three-phase separator; biogas is collected for treatment and utilization, sludge settles back to the reactor, and supernatant flows into the subsequent treatment unit.
Subsequent treatment stage: Anaerobic effluent flows into aerobic tank, sedimentation tank and other processes for further treatment to meet discharge standards. Excess sludge is discharged regularly for dewatering and drying treatment.
