Research On The Configuration And Operation Strategy Of District Heating System Based On Large Temperature Difference

Currently, a lot of wasted energy exists in cogeneration process, the emission heat from traps of power plant is one of the main ways .At the same time,there is a phenomenon that the existing power plant has a shortage of heating capacity. With the gradual progress of the acceleration of urbanization, this phenomenon will be more prominent. General points of view, for the case of insufficient heating capacity of the heat source,usually take a new heat source to solve the problem. Due to limitations of national and local energy and environmental policies,this method has been difficult to use. Even if approved, due to the existing pipeline network has been designed to meet or exceed the original heating capacity, so addition to the new large-scale heat plant, there need to transform the existing pipeline. As we all know, the investment of pipe network occupy a large proportion, so the transformation of the existing pipeline network will be a costly project. Meanwhile, due to the complex urban underground pipelines, it is a huge challenge for pipe network transformation, if not impossible conducted. Tsinghua University, based on the current status of the central heating system, put forward a new technology can alleviate current situation.Firstly, this paper discusses the ways to improve the utilization of waste heat.According to the characteristics of the Northeast Climate, combined with the actual situation of a heat transfer stations in Harbin,the paper chooses a reasonable heating program which would be analyzed in technical aspects. Secondly, through the establishment of a large temperature difference heat exchanger unit model, and simulating key device parameters of large temperature difference heat exchanger unit, the paper obtains operational status at different times during the heating season and operating conditions. Thirdly, rationally design the controlling operation plan of the system to ensure maximum energy efficiency of its operation. Finally, combined with engineering design, estimating the cost of the initial investment and operating and contrasting with the traditional way of heat exchange, the paper obtains recovery period, analysis economic feasibility, and make environmental benefits assessment.