燃煤电厂CO2捕集中烟气预处理系统的优化模拟

摘要

In coal-fired power plant CO2capture, in order to improve capture efficiency, flue gas pretreatment is required. In order to further improve flue gas quality at pretreatment outlet, Aspen Plus simulation was used to optimize flue gas pretreatment to study combination packing, packing layer height, absorbent quantity, and absorbent placed in separated layers,and investigate their influence on content of SO2at outlet, desulfurization efficiency and flue gas outlet temperature to determine the optimal process conditions. Adding different kinds of combination packing, different models of combination packing and absorbent placed in separated layers increased desulfurization efficiency and reduced flue gas pretreatment ioutlet temperature. With the increase of packing layer height and quantity of absorbent, flue gas temperature and content of SO2at flue gas pretreatment outlet decreased. Optimal packing layer height was 2—4m,and optimal absorbent quantity was (250—350)×103kg/h.%在燃煤电厂 CO2捕集中，为了提高其捕集效率，需对进入系统的烟气进行预处理。为进一步提高进入系统烟气的质量，本文用Aspen Plus模拟优化烟气预处理系统，通过研究在预洗塔中组合填料、填料层高度、吸收剂进量和分层进吸收剂对出口烟气中SO2的含量、脱硫效率以及出口烟气温度的影响，得出最佳的工艺条件。模拟结果表明，加入不同种类组合填料，同种类不同型号组合填料和分层进吸收剂都使烟气脱硫效率增加，出口烟气温度降低；随着填料层高度和吸收剂进量的增加，出口烟气中 SO2的含量和出口烟气温度降低，其中最佳的高度为2～4m，最佳的吸收剂进量为(250～350)×103kg/h。