烟气CO_2矿化产品干燥过程能量梯级利用研究

Energy Cascade Utilization Study of Flue Gas CO,Mineralization Product Drying Process

针对50000Nm^3/h烟气CO_2矿化磷石膏联产硫酸铵与碳酸钙工艺,提出了烟气余热梯级利用技术路线。将烟气余热按温度由高到低依次转化为动力以及产品干燥所需热能,动力循环中工质的冷凝则直接作为碳酸钙流化床干燥器的内热源。干燥工段消耗的热量汇集于75℃低温烟气中,利用热循环水直接接触烟气回收该热量为碳酸钙振动流化床预热器供热,同时将降温脱湿后的干燥尾气用作预热器的干燥介质,实现能量的高效利用。

For 50000 Nm3/h flue gas CO_2 mineralization phosphogypsum co-production with ammonium sulfate and calcium carbonate process,this paper proposes the flue gas waste heat cascade utilization technology route.The flue gas waste heat is successively converted into power and heat required by product drying according to the temperature from high to low.The working fluid condensate in power cycle is used directly as an internal heat source for calcium carbonate fluidized bed dryer.The heat consumption in drying section is collected in the 75℃ low-temperature flue gas.By means of hot circulating water direct contacting with the flue gas for heat recovery is to supply heat for calcium carbonate vibration fluidized bed preheater,while the drying tail gas after cooling and dehumidifying is used as drying medium of preheater,which achieve efficient utilization of energy.