Research Of Flue Gas Waste Heat In China Resources Power(Fuyang)Co.,Ltd

As the pillar industry of electric power in China,thermal power industry plays an irreplaceable role in national life and production.The four main engines of thermal power plants are boiler,steam turbine,generator and environmental protection facilities.As the main loss of the boiler,the exhaust smoke loss refers to the heat loss taken away by the flue gas.This part of the heat loss accounts for 50%of the heat loss of the boiler,and generally accounts for about 7%of the boiler loss.Effectively using this part of heat can not only bring economic benefits to enterprises,but also is regarded as the major measure that can be taken to promote the country to achieve energy conservation and emission reduction and sustainable development.Installing the flue gas of low temperature economizer behind air preheater and before electric dust removal and heating condensed water with waste heat is a more common method to utilize waste heat from flue gas at present.This kind of low temperature economizer flue gas waste heat utilization system has the advantages of simple structure and convenient operation.However,the low temperature economizer is prone to leakage and ash accumulation after the operation of this kind of utilization mode.The water after leakage is easy to flow into the electric dust removal,which leads to the difficulty of transporting ash of electric dust removal.China Resources Power（Fuyang）Co.,Ltd.adopts a more common low temperature economizer flue gas waste heat utilization system.Since installation and operation,there have been a total of 15 leakage times,and the first wear and leakage place is the windward surface pipe row of each group of low temperature economizer.With the increase of wear and leakage frequency,the second and third heating surface pipe row are also forced to withdraw from operation one after another.Secondly,the leakage of low temperature economizer in China Resources Power（Fuyang）Co.,Ltd.caused four incidents of water intake of ESP,and some electric fields of ESP were forced to withdraw from operation.A large amount of compacted dust was accumulated in the ash hopper,which seriously affected the operation safety of ESP and the safety of equipment structure.Based on the current way of waste heat utilization of China Resources Power（Fuyang）Co.,Ltd.and the level of utilization of low temperature economizer flue gas waste heat system,this essay put forward three different kinds of plans of reforming the use of waste heat,and the thesis carried on the arguments and analyses of the three plans,and then summarized,finally determined the plan which effectively made use of waste heat of flue gas and considered low temperature economizer and the electric reliable running.Based on practice,it has higher pertinence,stronger practicality and better maneuverability.If the retrofit scheme be born,it can effectively solve the most common problem that current level of 600 mw low temperature economizer flue gas waste heat utilization system putting-in-service proactively rate is low,and the problem of high leakage rate,and flue gas waste heat utilization can be made use of well,effectively and the high exhaust temperature chimney corrosion can be effectively eased to prevent the SO₂of rotary GGH leakage,ease the white smoke and smoke chimney rain phenomenon.In addition,it is also good for subsequent large coal-fired boiler system designed to provide a better way of thinking and direction.