Up Flow Anaerobic Sludge Blanket (UASB)

Wastewater treatment, especially by Biological system, is considered to reduce the pollutant concentration. It does it through microbial coagulation and by removing non-settleable organic colloidal solids. UASB (Up flow anaerobic sludge blanket) technology reactor is a form of anaerobic digester. It is used for treating wastewater. A UASB reactor is a methane-producing digester. It is believed to use an anaerobic procedure and form a blanket of granular sludge and is processed by the anaerobic microorganisms.


UASB reactor is designed on the ground of the so-called three-phase separator. It enables the rector to split gas, water and sludge mixtures under high turmoil situation. This allows for compact, cheaper designs. This reactor necessarily has several gas covers to separate biogas. The larger amount of gas or water interfaces helps reduce turbulence to a great level, making moderately high loading rates of 10 – 15 kg/m3.d possible. Separation in the UASB reactor needs just 1.0 meter of height. So it stops flotation effects and, as a result, floating layers.

Usually, at some stage in the performance of UASB reactor, the substrate first passes through an expanded sludge bed. This bed contains a high attentiveness of biomass. Then the left part of substrate passes through a less dense biomass. It is named the sludge blanket.

After this, a peristaltic pump pumps the influent to the UASB reactor from bottom. By this way, the influent moves upwards and gets contacted with the biomass in sludge bed. It continues to go upward. On the contrary, the rest substrates proceed with the biomass again in the sludge blanket, which has a lesser amount of concentration of biomass when compared with the sludge bed below.

It helps make sure a stable effluent quality. The A3 phase separator, which is placed above the sludge blanket helps divide the solid particles from the mixture (gas, liquid, and solid) after treatment. It allows liquid and gas to flow away from the UASB reactor. This, the water is treated