MBR, also known as Membrane Bio-Reactor, is a new kind of water treatment process which combines the membrane separation unit with the biological treatment unit. Due to the filtration of the membrane, organisms are completely retained in the bio-reactor, which realizes the full separation of HRT (hydraulic retention time) and the sludge retention time, as well as the high MLSS of the bio-reactor. With high nitrification performance and pollutants removal efficiency, Bio-reactors are primarily used to treat Industrial waste water of high concentration and recycling reclaimed water of municipal and domestic sewage.