Study On Energy Utilization And Energy Conservation Technology Reformation Of The Thermal Power Plant

Based on the guidance of energy conservation and environmental protection ideas, a comprehensive analysis of energy cascade utilization is made. The analysis is about the combined heat and power (CHP) system in the production process of a thermal power plant in Qingdao City. The energy loss distribution of the CHP system is scientifically evaluated, which provides the basis for the energy saving and reformation of the system. Through the analysis of energy utilization, a conclusion is drawed that the total thermal efficiency of the whole thermal power plant is relatively high in the heating season, averagely more than 74%; however, not in the heating season, the total thermal efficiency of the whole plant declined sharply, with only 42.1% at the minimum.According to the operation data recorded of the thermal power plant, the first and second laws of thermodynamics are used to quantitatively calculate the major thermal and economic indexs of the twelve months. The energy loss quantity of the main energy using site in the thermal power plant is also calculated. On the basis of these, the key energy loss site is found, which is in the cold-end. The cold-end energy loss is 58.1% of the total energy in July, and that is 23.8% of the total energy in December. In the condenser, stainless steel heat-transfer enhancement tubes with multidirectional turbulent flow takes the place of brass tubes, enhancing the heat transfer effectiveness and corrosion resistance. In the cooling tower, PVC "S" wave ripple splash packings are used, which increase splashing water area and enhance the cooling effect of cooling tower.In summer, the generated power reduces at a result of lower condenser vacuum. In order to solve the problem, an improving technical program about the condenser and cooling tower in the cold end is proposed. The program's argumentation on energy saving and economic efficiency is studied. Based on the original cogeneration system, a combined cooling, heating and power (CCHP) system with the lithium bromide absorption chiller is designed. In summer, the CCHP system uses the extracting and exhausting steam of heating unit as heat source to make about 7℃coolant water in concentrated cooling district. This increases heat load and the power generation capacity in summer, also improves the thermal economy. At the same time, the air-conditioning electric power consumption is saved and the difference between peak and valley power load is reduced. Grid economy is improved meanwhile. If the CCHP system is applied in summer, the total thermal efficiency of the system will reaches 79.6%, which is increased by 36.5% in comparison of the CHP system in July. The primary energy saving rate reaches 45.8%.