Safety Test Evaluation And Improvement Measures For The Sewage Collection And Conveying System In The Main Urban Area Of Hangzhou

In recent years,with the rapid development of urban construction and the increasing population,the pressure of collection and transfer system of sewage has been increased rapidly.The construction of the subway,viaduct and tunnel,etc.has caused more or less harm to the blood vessels of the city.Recently,a series of sewage system emergencies have caused us to attach great importance to the operation safety of the sewage system.It is urgent for us to evaluate the rationality of the original sewage system layout,the safety of the operation and whether it can meet the require-ments of urban long-term planning development.Adhere to the guidance of Scientific Outlook on Development and to build a healthy urban blood system as the goal need us to utillize scientific methods of analysis to evaluate the problems existing in the current urban sewage system and facility operation comprehensively and systematically.In accordance with the relevant requirements of "five water co-governance and pollution control first",the rationalization proposals for the construction and renovation of urban sewage systems and facilities are put forward to la-y the foundation for the construction of "beautiful Hangzhou".Based on the problems found in operation and management of sewage collection and conveying system,this paper adopts AHP(Analytic Hierarchy Process)to evaluate the safety of sewage collection and conveying system in the main urban area of Hangzhou.The main contents of the paper include:(1)Determine the evaluation method.The theory and method of AHP are studied and discussed.AHP can effectively reflect the characteristics of sewage system.The selection of evaluation index system and weight are scientific,reasonable and in line with the present situation,propose the safety test evaluation scheme for urban sewage collection and transportation system based on analytic hierarchy process.(2)Design the Assess model.According to the group meeting to decide the weight of each part,the final result is obtained through the model calculation,and the health grade of each pipeline network is determined by comparing the health level of the system.The results of the model analysis can be used to evaluate the level of submain of the three fouling systems.① 3-3 submain is in the middle risk level.3-1 submain,3-2 submain,3-4submain and 3-5 submain are under sub-health condition.The evaluation level of the main pipe system of Qi-ge sewage system:The second sewage system is in the middle risk level;② The first sewage system and the Si-bao transfer main pipe are at the light risk level;③ The third sewage systems,fourth sewage systems,fifth sewage systems and sixth sewage systems are in sub-health status.Evaluation level of Qi-ge sewerage system:the Qi-ge sewage system is at a light risk level now.According to the existing problems of system risk,quality risk,capacity risk and operational risk,different corrective measures of adjusting the sewage system,connecting project arrangement,improving existing facilities were proposed then Decision-making basis for the construction and improvement of sewage system was provided.The security performance study of Hangzhou main city sewerage collection and conveying system can cognize the shortage of the sewerage system well,find out the risks and propose improvement measures in time.It is conducive to the healthy development of the urban sewage system follow-up,and provide guarantees for the safe operation of urban sewage facilities.