Research On Waste Heat Recovery System Of Heat Pump On Membrane Wall Desulfurization And Heat Exchanger

Under the background of energy conservation and clean heating,the emission control of flue gas pollution from coal-fired boilers is becoming more and more demanding.Due to the huge desulfurization equipment,complex process and high production cost on site,the construction or renovation period is long,and a large amount of waste heat of flue gas is not utilized,which leads to excessive water evaporation at circulating temperature in the tower,and leads to the problem of flue gas corrosion at low temperature in the tail flue gas.Based on the above problems,this paper designs an integrated desulfurization and heat exchange device that can be pre-manufactured in a factory and quickly assembled on site,and uses the heat pump waste heat recovery system to recover this part of waste heat for urban heating,achieving double benefits of energy conservation and emission reduction.?1?According to the limestone-gypsum wet desulphurization characteristic and the difficulty of recovery of waste heat,the desulfurization diaphragm wall heat transfer heat pump heat recovery system has carried on the simple model building and the nickel base alloy steel anticorrosion materials and glass flake anticorrosive performance was analyzed,and the results show that these two kinds of material construction speed is quick,strong anticorrosion performance,suitable for as the body of the diaphragm wall heat transfer device for desulphurization material.A membrane wall desulfurization heat exchanger heat pump waste heat recovery system is established.Heat exchange is carried out by spraying the wall surface in the tower.The circulating water in the wall is absorbed and used as a low-grade heat source of the heat pump unit to heat the return water of the heat network.?2?The heat transfer principle and thermal resistance model of the device system were analyzed and established,and the optimal flow velocity area under different pipe diameters was given.Also introduces the procession of the desulfurization principle and analyses the influence factors of affecting desulfurization efficiency,quantitative device for flue gas velocity is given in 3-5 m/s spray particle size should be 1.2-1.5 mm,12-18,liquid run Ca/S should be between 1.02-1.05,through the heat transfer effect can effectively keep the serous about 50°C value in the design,absorbing slurry p H should be kept between 5.4-5.7 device can effectively improve the desulfurization rate.Through40T/h boiler desulfurization diaphragm wall heat transfer heat pump heat recovery system has carried on the design case analysis,the results show that should be a reasonable adjustment device of the circulating water flow rate in order to make sure to enter the temperature of the heat pump evaporator can effectively improve the COP of heat pump,heat pump device can provide 9 mw heat for urban heating,can increase the heating area of 180 thousand m².?3?Finally,combining case analysis and calculation results,through the payback period of static and dynamic payback period of two methods of economic evaluation of the device are analyzed in economics,the calculation results show that the use of heat recovery of waste heat to improve the economic benefits of coal heating heat source use efficiency is good,the static payback period can be in 6 years of recovery of the initial investment cost of the equipment system,the dynamic payback period can recycling initial investment cost in the next 10 years.At the same time,the environmental benefits are also considerable.The desulphurization efficiency of the desulfurization unit is maintained at more than 90%,and the annual SO₂ emission is reduced by 4039.2 tons,achieving triple benefits of economy,energy conservation and environmental protection.