A Study Of UASB-SBR Process On Treating Urban Sewage

Although wastewater treatment plants in large scale have been builded in many large cities, more small cities can not afford the funds of building them. Aiming at the fact that the low concentration and the little amout of domestic sewage in small cities, this paper presents Upflow Anaerobic Sludge Blanket (UASB) as the first part in advance and SBR process to remove N ,P and CODcr. Then we testify its feasibility by experiment, especially the research in little scale and its stability.Some experiments on varying factors on UASB such as temperature, pH and we get the most suitable conditions.The results indicates when hydraulic retention time (HRT) is 4h, theconcentration of CODcr at exportation is 36.05mg/L~95.99mg/L and came to the second class of GB8978—1996.The results also indicated that the UASB working steadily and have good removal effect on organic matter .UASB has a excellent ability of bearing high impact loads. SBR as a process afterward can remove N, P effectively at the most suitable conditions we get through experiments. The water at exportation is perspective and CODcr, N and P measured with the fist class of GB8978-1996.Comparing with the secondary treatment process , the costs of construction and operation of UASB—SBR process is much lower. And every index of the ultimate water is approach to or measured with the demand in water used in life and landscape. Furthermore CODcr, SS and NH3 measured with the demand of cooling water in our country, so it is worth doing more completely research in wastewater reuse and saving up resource of water.