Study On Demestic Wastewater Treatment Of Carrier Performance By Biological Contact Oxidation Process

In the wastewater bio-treatment technology, the BCO (Biological Contact Oxidation) is a high efficient treatment technology, biofilm carrier is the factor of this method, which performance directly influences and restricts the efficiency of the process, choose the suitable biofilm carrier could effectively improve the BCO process treatment effect. In this paper, which experimental research on three representative kinds of biofilm carrier (soft fiber carrier, elastic carrier, suspended spheroidal displacement carrier).By the analyzed the reactor removal effect of COD and ammonia-nitrogen, we could conclude as follows:(1)BCO process has a fast speed for membrane forming. soft fiber carrier has the fastest speed for membrane forming rate, only need six days, suspended spheroidal displacement carrier need eight days, elastic filler need ten days.(2) As to the artificial sewage simulation, when the reactor was operated in the mode of continuous flow and continuous aeration, the suspended spheroidal displacement carrier was better to remove COD and ammonia-nitrogen than soft fiber carrier. Using suspended spheroidal displacement carrier, when HRT=12h, the average effluent COD was 42.8 mg/L, the average removal rates of COD was 86.8%, the average effluent ammonia-nitrogen was 14mg/L, the average removal rates of ammonia-nitrogen was 51.5%. Which can achieve the first class of Integrated Wastewater Discharge Standard (GB8978-1996).(3)When the BCO process intermittent operation, under the constant influent using elastic filler, the reactor is operated 3 times one day (HRT=24h), and the cumulative aeration time was 6 hours, the average effluent COD was 61.8mg/L, the average removal rates of COD was 75.8%, Which can achieve the first class of Integrated Wastewater Discharge Standard (GB8978-1996).(4) The BCO process intermittent operation also has certain removal efficiency of ammonia-nitrogen. The results showed that: under the design flow using elastic carrier, the reactor was operated 3 times one day (HRT=24h), and the cumulative aeration time was12 hours, the average effluent ammonia-nitrogen was14.5mg/L, the average removal rates of ammonia-nitrogen was 52%, Which can achieve the first class of Integrated Wastewater Discharge Standard(GB8978-1996). (5) Based on the Monod equation, by the test results of suspended spheroidal displacement carrier, the dynamics model of the BCO reactor for artificial sewage was proposed as:...