The Initial Discussion Of Decision Methodology On Sewage Treatment Facilities Of Town In Changshu

As the early city to put sewage treatment into effect in town,there has a lot of experience about sewage treatment facilities’ construction,operation and management in Changshu,which is worth to be used for reference.It is undeniable that many problems about not only uptime rate but also treatment effect,which exist in built sewage treatment facilities of Changshu,need to be solved.This paper will make a performance assessment about rural sewage treatment facilities of main craft,by means of decision analysis,to provide reference in planning of rural sewage treatment facilities.The specific contents of this paper are as follow.(1)To collect data of rural sewage treatment facilities,that researched by related people in Changshu.To analyze these data,then to summarize the status of rural sewage treatment facilities in Changshu City.(2)To introduce the concept of participatory decision-making that afford someone to make decision in the field of sewage treatment facilities,and to elaborate steps of participatory decision-making process: problem identification,diagnosis,design of solution options,selection of best solution,intervention and evaluation.(3)To elaborate stages of multi-criteria decision analysis method: identification of problems,formulation of objectives,criteria and indicators,listing of options,making a performance matrix,trading off strengths and weaknesses of various options,sensitivity analysis.Multi-objective or multi-criteria decision analysis can be applied to complicated multi-stakeholder decision problems as there are frequently found in the field of infrastructure,but also for personal decisions in which there is only one stakeholder/decision maker.The next sections explain the five different stages of multi-criteria-decision processes: identification of problems,formulation of objectives,criteria and indicators,listing of options,making a consequences table,and trading off strengths and weaknesses of various options in a situation under study.(4)To make a performance assessment about rural sewage treatment facilities of main craft about MBR,biological contact oxidation process,and SBR,using the method of multi-criterion decision analysis.The performance ranking that chief kinds of craft about different criterion in Changshu is showed as follow,about buildingfinance is as follow: Biological filter+ Artificial wetland > MBR > Biological contact oxidation process>SBR.About land-use situation is as follow: MBR>SBR>Biological contact oxidation process>Biological filter+ Artificial wetland.About removing of COD is as follow:MBR > Biological contact oxidation process >Biological filter+ Artificial wetland > SBR.About reliability of craft is as follow:MBR> Biological filter+ Artificial wetland> Biological contact oxidation process> SBR.It takes such ranking of criterion-importance that: reliability of craft >removing of COD > land-use situation > building finance,then the ranking after make trading off about weight allocation is as follow: MBR > Biological contact oxidation process>Biological filter+ Artificial wetland>SBR.