化学吸收法CO_2捕集解吸能耗的分析计算

Analysis and calculation of the desorption energy consumption of CO_2 capture process by chemical absorption method

推导出了化学吸收法CO2捕集工艺解吸总能耗的准确计算公式,根据年产量100万吨CO2的捕集工艺流程的节点参数,分析计算了解吸能耗中各项能耗的大小,并与Leites、晏水平、王海波等能耗估算公式结果进行了对比。分析表明,本文推导的能耗计算公式适用于设计后或运行时的能耗计算,在捕集工艺设计前可采用Leites、晏水平、王海波等公式估算解吸能耗。其中晏水平公式考虑了循环倍率,因此能耗估算公式的适用性强,循环倍率和比热容取值偏差不大时,估算精度较高。通过对推导出的解吸能耗公式的分析,即使吸收剂质量浓度、溶液的再生度、贫富液换热器的性能一定,仍能进一步降低解吸总能耗,并提出了进一步降低解吸总能耗的有效措施。

A generalized calculation formula for the desorption energy consumption was derived and described in detail based on the mass conservation,the energy conservation and the desorption process analysis. Based on the node parameters of the 1 Mt/a CO2 capture capacity,the energy consumptions of the desorption process were analyzed and calculated with the results calculated from equations given by Leites,Yan Shuiping and Wang Haibo. The derived formula in this paper was suitable for energy consumption calculations after process design and at run time. The equations given by Leites,Yan Shuiping and Wang Haibo can be used to estimate the desorption energy consumption before the design for the capture process. If the values of the circulation ratio and the specific heat capacity were accurate,the equation given by Yan Shuiping was practical and accurate. Finally,corresponding measures were presented to reduce the desorption energy consumption according to the calculation formula,even though the absorbent concentration,the regeneration degree of the enriched absorbent and the heat exchanger performance were fixed.