Regulation Scheme Study Of Flue Gas Waste Heat Power System In Variable Condition

Energy shortage and environmental pollution are the two major challenges humans face.The medium and high temperature flue gas waste heat for power recycling can achieve energy saving and emission reduction,in line with sustainable development strategy.In practical application,the mass flow and temperature of the flue gas waste heat source fluctuate,and the dynamic system needs to be adjusted accordingly to ensure the safety and optimization of the system.Based on the transcritical circulation system of organic working fluid,five kinds of adjustment schemes to cope with the change of heat source flow and temperature including the minimum mass flow of gas(MMG),variable mass flow of working fluid(VMF),auxiliary heating(AH),heat storage(HS)and the minimum temperature of gas(MTG)were put forward.For the condition of 20% flow fluctuation range and 100 ? temperature fluctuation range,the optimization studies aiming at the optimal system economy and the economic comparison of the five adjustment schemes were carried out.The results show that:(1)VMF is the best in the regulation schemes to deal with the change of heat source temperature,and the greater the fluctuation range of flue gas temperature,the more obvious the economic advantage.When the temperature fluctuation is 100 ?,the energy production cost of VMF is at least lower 4% than that of MTG.(2)In the regulation schemes to solve the flow change,the energy production cost of VMF and AH is lower than the others.In the inspection range of the paper,the difference of energy production cost for the two schemes is less than 4%.(3)In the adjustment scheme of the change of heat source temperature and flow rate,this paper proposes the scheme of VMF,which is superior to both economic performance and waste heat utilization.