摘要
本文评估了处理矿物燃料电厂烟气中 CO_2的5种方法:(1)纯氧燃烧/烟气再循环;(2)可再循环使用的溶剂洗涤(如单乙醇胺);(3)低温分馏烟气中 CO_2;(4)选择性膜扩散分离CO_2;(5)海水洗涤 CO_2。分离后的 CO_2在150atm 下进行液化,采用管道输送,通过扩散器释放 CO_2到海洋深处模式计算表示:适当条件下释放 CO_2能够完全溶解在海水中。方法(1)所需要能量最小,大约为消耗30%煤耗总能量。不包括管道和深海处理的投资费用,那末电价将增加80%,
The capture and disposal of carbon dioxide from the flue gas of fossil-fueled power plants is technically feasible,albeit it requires a significant fraction of the energy content of the fossilfuel and additional equipment with large capital expenditure.The five processes in- vestigated for capturing CO_2 from the flue gas of coal-fired power plants are(a)combus- tion of coal in an atmosphere of oxygen and recycled flue gas;(b)scrubbing the flue gas with a recyclable solvent(monoethanolamine);(c)cryogenic CO_2 fractionation of the flue gas;(d)separation of CO_2 by selective membrane diffusion and(e)scrubbing of the flue gas with seawater.The captured CO_2 is envisioned to be liquefied at 150 atm,piped to the deep ocean,and released through a diffuser,Model calculations show that with appropriate re- lease conditions the formed CO_2 drops can be completely dissolved in seawater.The process that requires least incremental energy is air separation/flue gas recylcing.In this process about 30% of the total energy content of the coal is consumed,and the thermal efficiency of a power plant is reducted from 35% to about 25%.Excluding pipelane and deep water dis- posal costs,we estimate that electricity production costs will increase by about 80%.
