Membrane bioreactor is a new type of wastewater treatment process which is an organic combination of Membrane technology and sewage biological treatment technology.It originated in the United States in the 1970s.
Advantages of MBR in pharmaceutical wastewater treatment
1. High separation efficiency and guaranteed effluent quality
Pharmaceutical wastewater contains a large number of suspended substances, and the suspension and turbidity in the effluent are close to zero through membrane separation.In addition, because the wastewater contains toxic substances, easy to lead to sludge expansion phenomenon, in the membrane separation, will not affect the quality of effluent.
2. High sludge concentration and strong biochemical capacity
Almost all the activated sludge can stay in the reactor, and the sludge concentration of MBR can be effectively improved. The sludge concentration of MBR can reach 3000mg /L.Compared with the traditional process, it can improve the sludge concentration and avoid the loss of activated sludge after sludge bulking.Due to the high fluctuation of the quality and quantity of pharmaceutical wastewater, the increase of sludge concentration increases the treatment capacity of the reactor and can bear a higher impact load.
3. Improve the purification efficiency of refractory organic matter, and shorten the hydraulic retention time
The refractory organics in pharmaceutical wastewater are trapped in the reactor, and the contact time with microorganisms is more than that of traditional biological method, which is beneficial to the cultivation of some obligate microorganisms and improves the purification efficiency of refractory organics.In addition, due to the high purification efficiency of refractory organic compounds, MBR can shorten HRT under the premise of ensuring the effluent quality.
4. Good growth of nitrifying bacteria and good ammonia nitrogen removal effect
The membrane of MBR cannot trap ammonia nitrogen, leading to the high ammonia nitrogen removal rate of MBR mainly due to the presence of a large number of nitrifying bacteria in the reactor.Under the action of membrane separation, slow-growing nitrifying bacteria are kept in the reactor, creating favorable conditions for their growth and reproduction.The accumulation of nitrifying bacteria in the reactor makes MBR have a high removal effect on ammonia nitrogen.In previous engineering cases, suke used the combined process of activated sludge method, hydrolysis and acidification method and MBR to treat the wastewater of a chemical pharmaceutical factory. The ammonia nitrogen concentration in the inlet was 72.8-92.4mg/L, and the results showed that almost all the ammonia nitrogen was removed in the MBR pool, the ammonia nitrogen concentration in the effluent was 1.4-4.1mg/L, and the total removal rate was 94.5-97.6%.