Study On Comprehensive Assessment Of Wastewater Treatment Plants In Jiulong River Catchment Based On The Method Of Life Cycle Assessment

As the urbanization in China, most of population will be living in small and medium-sized towns in the future. At present, the environmental issues of small and medium-sized towns are brought to the forefront more and more, and the main part of wastewatet treatment is transferring from big cities to small and medium towns, consequently, the small and medium-sized wastewater treatment plants are progressively increasing. Exploiting life cycle assessment method to comprehensively assess the wastewater treatment technics of wastewater treatment plants in small and medium town, we could qualitatively and quantitatively analyze the environmental influence of different treatment technics in a whole wastewater treatment life cycle, and provide referenced information for the construction of wastewater treatment plants in the future.As an effective environmental management tool, life cycle assessment has been widely employed by countries and regions in the world. And as a tool to assess the environmental influence of the process from 'cradle' to 'tomb' of a kind of product, technics or service, it tracks the whole course of raw material collection, manufacture, use of product and the disposal of product, and adopt quantitative and qualitative method to evaluate it.As for using life cycle assessment method to evaluate the wastewater treatment technics of wastewater treatment plants, the key is how to correctly apply the life cycle assessment methods to the three parts of wastewater treatment: wastewater collection, wastewater treatment, wastewater disposal and sludge disposition. This dissertation filters 14 factors of influence from economic benefit, technical characteristic and environmental effects, and determines the weight of every factor of influence in the wastewater treatment lify cycle.This dissertation choose Longyan Xinluo District Wastewater Treatment Plant and Changtai County East District Wastewater Treatment Plant as engineering case, in addition, the former employs A/O technics and the later employs Biolak technics. We use life cycle assessment method to compare the wastewater treatment process in detail, and the ultimate aim is to determine which technics is more suitable forsmall and medium-sized town wastewater treatment plants.This dissertation apply environment load method in the environmental influence quatifucation, and apply efficiency coefficient method and analytic hierarchy process in analyze hierarchical chart. Assessment runs through the whole wastewater treatment life cycle course, at last we could gain advantageous advices, and provide basis for environmental managers when they make a strategic decision.