Study On The Treatment Of High Ammonia-nitrogen Wastewater With Immobilized Nitrogen Removal Bacteria

In this study，Immobilized microorganism technique and the short-cut nitrification andde-nitrification process method were integrated to treat High Ammonia-NitrogenWastewater. A way to enrich ammonia oxidizing bacteria is achieved by controlling theenvironment in which high(5mg/L±) and low DO(0.5mg/L) occur alternately in a SBRreactor. By maintain the DO below0.5mg/L, pH=8.6±0.5，and temperature keptbetween25and30℃, the concentrations of free ammonia,CODcr and sludge age willhave no impact on the Shortcut nitrification process. The results showed that to maintainenvironment in which high and low DO occur alternately is the key to achievingshort-cut nitrification. A series of laboratory experiments on optimizing preparationmethods of microorganism particle were conducted by use of PVA and SA material asmain materials respectively. Polyvinyl alcohol (PVA) and SA were employed toimmobilize microbes within the granules, and the optimized formula is8%PVA,0.3%SA,4%Sio2, and linking cross time of24h;4%SA,0.4%activated carbon and linkingcross time of24h. A quality evaluation system of immobilized microbe granules ispresented in aspects of physical, chemical and microbial index. experiment results thatwhen the temperature is29℃, DO is about5.5mg/L, and PH is between7.8-8.2,thetreating effect is best and accumulation of nitrite bacteria is above90%.