Research On Optimization Of Distrct Heating System Using Petroleum Refining Industrial Waste Heat

The heating area in China is increasing at a rate of 10% yearly, and it results in a shortage of heat resources in the North of China. What is more, a large area of fog generated by heating in winter forces us to look for new district heating resources, so that we can solve the increasingly serious environmental pollution problems.Recently the petroleum refining enterprises are faced with severe pressure in the energy saving and consumption reduction aspects. A large number of low grade heat produced in the production process are discharged directly into natural environment. For lacking of suitable low temperature heat users, solving the problem of low temperature waste heat utilization is one of the key and difficult point for the current industrial energy saving. So utilizing waste heat for district heating can provide a solution to the application of low grade waste heat and reduce the consumption of the petrochemical material of large new central heating heat source, The thesis research the most proper way to use the petroleum refining waste heat for district heating.Base on the actual data of investigation, this thesis summarizes the rules of waste heat such as heat location, quantity of wast heat, in typical refining unit, and presents the characteristics of different kinds of waste heat. This thesis also present a method of waste heat integration and visually show the characteristics of the waste heat distribution in a petroleum refining factory, after analyzing the own demand for the waste heat, we finally conclude the waste heat resource can be used for the district heating.Revealing the essence of district heating system using waste heat, is three heat transfer process for petroleum refining factory, heating stations and heat users. Through studying and comparing the heating station configurations, we select the most efficiency one for the system. Through researching the heat transfer in the refining industry, we change the return water temperature and analyze the fluctuation of pinch point temperature. After rising the supply temperature of heating water, we select the most efficiency configuration for the heat transfer process in the factory. Through analyzing the heat transfer process, we finally determine the initial process of district heating system using waste heat, and analyzes the whole operation mode in the heating season.The thesis reveals the essence of the system configuration optimization and proposes the annual cost as system optimizing index, building the economy mode for the system. Through analyzing the influences of the factors such as temperature, distance and heat removal rate, we finally obtain the optimal system configuration and operation parameters under different conditions.Using of the conclusion of the research above, we design the district heating system using the waste heat of A petroleum refining factory. Through technical and economic analysis, we conclude the feasibility of practical application.