In order to explore methods of improving phosphorous and nitrogen removal in sludge reduction technologies, an advanced process combining sludge reduction and phosphorous and nitrogen removal was developed, for short, HA-A/A-MCO Process (Hydrolysis-Acidogenosis -Anaerobic/Anoxic-Multistep Continuous Oxic tank). Under the condition of this process achieving favorable effect of phosphorous and nitrogen removal and sludge reduction, test results of the process treating campus wastewater showed that when influent COD was 316-407mg/L, effluent COD was lower than 18mg/L, and COD removal rate exceeded 96%. When return ratio of anaerobic P-release sludge entering into hydrolysis-acidification tank was about 2% of influent flow, most anaerobic P-release sludge was translated into organic matter and it mainly contained VFA(about 275mg/L), which was 4.74 times as much as that(58mg/L) in original sewage. Supernatant which was rich in VFA from hydrolysis-acidification tank entered into subsequent A2/O cells, which could provide affluent carbon source for phosphorous and nitrogen removal.

Bacterial community structure of advanced HA-A/A-MCO sludge reduction process is analyzed by DGGE fingerprinting technology. Research results indicates that microbial flora showed the distinction of highly diversity in anaerobic tank, anoxic tank and MCO tank of the HA-A/A-MCO process, and each tank has its own diversified and stable dominant microorganisms, as so the co-activation of such preponderant bacterial community promotes the system to exert favourable and consistent function of phosphorous and nitrogen removal and sludge reduction.