Upflow anaerobic sludge bed reactor is an anaerobic biological method for sewage treatment, also known as upflow anaerobic sludge bed.
Sewage flows from bottom to top through UASB. There is a high concentration and high activity sludge bed at the bottom of the reactor. Most organic pollutants in the sewage are degraded to methane and carbon dioxide by anaerobic fermentation.
There is a sludge suspension layer above the sludge bed due to the agitation of water flow and bubbles. The upper part of the reactor is equipped with a three-phase separator for separating digestive gas, digestive liquid and sludge particles. Digestive gas is derived from the top of the reactor; sludge particles automatically slide down and settle to the sludge bed at the bottom of the reactor; digestive liquid is discharged from the clarification zone. UASB has a large load capacity and is suitable for the treatment of high concentration organic wastewater. UASB with good operation has a high removal rate of organic pollutants, does not need stirring, and can adapt to a large range of load shocks, temperature and pH changes.