Screening for the phosphate reducer and study on their dephosphorization conditions

The biological reduction for phosphate to phosphine can be used to develop a new biotechnology for phosphate removal from wastewater. A suitable inoculum should be prepared and the conditions of the reaction should be clear. By measuring the contents of total P both at the beginning and at the end of batch cultivation, the phosphate reduction activities of cow manure, swine manure, chicken manure and two kinds of anaerobic activated sludge from different WWTP were compared, and the swine manure was found to be the best of the inocula. Based on that, the swine manure was mixed with two kinds of anaerobic activated sludge at the mass ratio of 3∶1∶1, and the mixture was then used as the seeding sludge to test the optimal conditions for phosphorus removal in anaerobic surroudings. The results showed that the optimal carbon and nitrogen sources were glucose and peptone, respectively. The optimal initial pH value was 6.5 and the temperature was 35℃. Under the optimal conditions the maximal phosphate removal efficiency was 21.31% during the four-day cultivation. No obvious effect on the anaerobic phosphorus removal was found when molybdenum and other trace elements as well as sulfide as a reducing agent were added into the culture media.