Feasibility Study About District Heating And Cooling From The Sewage-source Heat Pump In Urban Sewage Plant

As China’s economy continues to develop, the continuous improvement of people’s living standards, and the amount of sewage produced by the city life is also increasing. China will develop scale municipal wastewater treatment plantin recent years. To the coming of 2015, China?s national domestic sewage treatment rate will reach 85 percent, compared with 77.5% at the end of 2010, an increase of 7.5 percentage points; the corresponding new sewage processing capacity of about 45.69 million cubic meters per day,then the national sewage treatment capacity will reach 208.05 million cubic meters a day. The fact that water from the sewage treatment plant has several apparent merits, including larger water flux, higher water source concentration and better water quality has created good conditions for the application of urban sewage source heat pump. Urban secondary effluent from sewage treatment plants should be developed vigorously to build more urban sewage source heat pump systems, which not only exploits effectively valuable cooling and heating resource in sewage, but also brings enormous economic, environmental benefits for the enterprise and the community.In this paper,The sewage treatment plant construction project water source heat pump system, and the establishment of a comprehensive analysis of sewage source heat pump heating system to the surrounding area of the feasibility of cooling. Use the ?DeST? software to simulate the dynamic load changes by three types of construction, and combined with simulation results and wastewater temperature, flow and other data, discussed the heating and cooling capacity of sewage; and solve the problem of the establishment of the reservoir and discuss the system energy and transport issues distances.In the process of analysis,determined the most unfavorable day in winter. In this day the sewage flow is small and the system load is large,make two cases discussed, that no reservoir and the establishment of the reservoir, only the establishment of the reservoir, heat pump system extracts heat from sewage to meet the load requirements of the system at any time. After the establishment of the reservoir, you can take advantage of water resources, the paper concluded after analyzing: The maximum amount of continuous dry period is the sum of the most unfavorable design capacity of the reservoir.For the design feature of small temperature difference and large flux, we discuss the influence on energy consumption caused by distance of transporting and establish the related model;Under the condition of the economic specific friction resistance, the judge computing formula for the biggest economic transporting distance of sewage heat pump system is shown in this paper, which provides the judging basis for the economical feasibility of actual engineering.