由于热电厂废气中含有高湿饱和水蒸气,选用疏水材料活性炭为吸附剂,利用真空变压吸附技术研究了活性炭分离电厂废气中水蒸气和二氧化碳的可行性和优越性,研究了水对CO2捕集的影响.实验分析表明,水在活性炭上的"S"型等温吸附曲线有利于真空条件下被解吸.同时,圆锥模型描述了水蒸气在吸附床内的浓度分布.结果表明,即使水蒸气可以被活性炭吸附,但它的存在不影响CO2的捕集.每个循环操作可在相对较短的解吸时间和较高的解吸压力下完成.实验中单床三步变压吸附工艺可以使CO2回收率高达80%,CO2纯度达43%.%Due to the high absolute humidity of real flue gas, activated carbon, a hydrophobic adsorbent, was used to selectively adsorb CO2 by vacuum swing adsorption in this study. The objective of this work is to study the feasibility and advantage of CO2 capture along with simultaneous moisture removal by activated carbon and the effect of H20 on CO2 capture from wet flue gas streams. Through experiment and analysis, the "S" shape isotherms of water indicated water was easier to be desorbed from activated carbon. Then a cone shape model was proposed to depict water distribution inside the adsorption bed. As a consequence, water vapor hardly influenced the CO2 capture performance. Moreover, the process can be operated under a relatively high vacuum pressure and short evacuation time. The preliminary results showed that our one-bed VSA process could yield a good CO2 recovery of over 80％ and a reasonable purity of 43％.
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