| As the global greenhouse effect intensifies,countries have imposed limits on carbon emissions.The installed capacity of China’s non-fossil-generating units has increased rapidly,and gradually occupied the living space of the firepower generators.In order to save the cost and improve the competitiveness,the thermal power unit has to carry on the transformation of frequency conversion and energy saving to the fan.When the inverter is running,it will heat up and produce a cold load.In this paper,the research work is carried out on the basis of the fan frequency conversion chamber of a coal-fired power plant in Loudi.The existing air-conditioning system in the frequency conversion room of the power plant is a traditional split-type air conditioner,which has the problems of low efficiency,high energy consumption and unstable operation in winter.In view of the problems existing in the existing air-conditioning system,this paper puts forward three new schemes: water-source heat pump system,fresh air natural cooling + existing air-conditioning system,fresh air natural cooling + watersource heat pump system,which can make use of the outdoor natural cold source cooling fan frequency conversion chamber,and compares its annual total energy consumption and economy,from which the optimal scheme is selected.In this paper,the load model of fan frequency conversion chamber is established by using De ST software.The hourly cooling load of fan frequency conversion chamber is between 234 k W-248 k W and no wet load is obtained.The energy consumption models of existing air-conditioning and water-source heat pump systems are established.The total annual energy consumption is 622139.16 k W·h and 331522.74 k W·h,respectively.According to the operating regulation of frequency converter,the outdoor state of 3points on the enthalpy-humidity diagram,there are 4259 hours of fresh air natural cooling,its annual energy consumption of 63021.48 k W·h.In view of the fact that the new air natural cooling system can’t meet the cooling demand of the frequency conversion chamber for 4501 hours,a new scheme of the new air natural cooling + the existing air conditioning system and the new air natural cooling + water source heat pump is put forward.The annual total energy consumption is 415416.57 k W·h and307314.57 k W·h respectively,of which the scheme 4(the new air natural cooling +water source heat pump system)is the most energy-saving scheme.The annual cost value is an important index to evaluate the economy.The annual cost value is composed of initial investment,operation cost and maintenance cost.The initial investment part is the total initial investment of the system,which is allocated to each year of the system life cycle according to the equal amount of time value.Because the thermal power unit can’t run all year round,the utilization rate of the thermal power unit is taken into account when calculating the annual operation cost.The annual cost of scheme 1(existing air conditioning system),scheme 2(water source heat pump system),scheme 3(fresh air natural cooling + existing air conditioning system)and scheme 4(fresh air natural cooling + water source heat pump system)are calculated respectively.The annual cost of scheme 3 is the smallest,which is 984 thousand yuan,which is only 75.46% of the annual cost of existing scheme.Considering the different cost of power supply in different factories,the annual cost chart under different electricity price is also drawn in this paper.The research in this paper has a definite value on the scheme selection and energy-saving transformation of the fan frequency conversion chamber and the industrial plant air-conditioning system similar to the hot and wet environment in the thermal power plant. |
PDF Full Text Request