The Typical City Secondary Sewage Plant Cost Models And The Optimization Design

This paper through the establishment the cost models of the oxidation ditch technology, ICEAS technology and A2/O technology which are the three typical urban secondary processes, the cost models established from the precision and adaptability are higher than the previous cost models,using the cost models and analytic hierarchy process for the process optimization of urban sewage treatment plants. This paper provides a new way of thinking for the construction of urban sewage treatment plants in the process of scheme argumentation and feasibility study.The cost models of urban sewage treatment plants established consist initial investment cost model and operation cost model, because the differences of scales and the regional differences in building cost models, this paper uses the current market price of kunming, building cost models for oxidation ditch process, ICEAS process and A2/O process, for three processing scale categories of 5-10 million m3/d,2-5 million m3/d,1-2 million m3/d.According to the cost models established and validated, draw the following conclusions:When processing scale is 1-3.7 million m3/d, A2/O invest the most, the oxidation ditch technology needs less investment, ICEAS technology's investment is minimum, When processing scale is 3.7-4.3 million m3/d, A2/O invest the most, ICEAS technology needs less investment, the oxidation ditch technology's investment is minimum, When processing scale is 4.3-4.7 million m3/d, A2/O invest the most, the oxidation ditch technology needs less investment, ICEAS technology's investment is minimum, When processing scale is 4.7-5 million m3/d, ICEAS invest the most, the oxidation ditch technology needs less investment, A2/O technology's investment is minimum, when processing scale is 5-10 million m3/d, ICEAS technology invest the most, the oxidation ditch technology needs less investment, the A2/O technology's investment is minimum. No matter at what processing scale, the unit cost of sewage treatment of the ICEAS process is the biggest, the unit cost of sewage treatment of A2/O process is less, the unit cost of wastewater treatment the oxidation ditch process is the least. According to cost models established, for 5-10 million m3/d of sewage treatment plant suggest compare the A2/O process with the oxidation ditch process. For 1-5 million m3/d of wastewater treatment process, suggest compare the ICEAS process with the oxidation ditch process.In the next place, introduces the analytic hierarchy process (AHP) in choosing the wastewater treatment process, when calculating the benchmark index strata in the model, the paper combine the cost models of urban sewage treatment plants established and AHP together, which can improve the reliability of the decision.