Abstract:

Aiming at the increasingly serious greenhouse effect and shortcomings of traditional CO₂-capture and storage technology (CCS), the two-stage and four-bed pressure swing adsorption (PSA) device was investigated to capture carbon dioxide from flue gas of power plant, which used carbon molecular sieve as the adsorbent of the first stage process and 13X zeolite as the adsorbent of the second stage process. In order to improve the recovery of CO₂, a cycle was added into the process. The mathematical model of the above process was established. Then experiment was carried out, and the accuracy of the model was verified by comparison between the results of experiment and simulation. Results of simulation displayed that the trace CO₂ (15%) in the flue gas could be enriched to 95% with a recovery of 93.92%. The productivity was 4.576 mol CO₂·h^-1·kg^-1 while the energy consumption was only 0.847 MJ·(kg CO₂)^-1. By comparing with other processes, this process has the characteristics of high recovery, high purity and large amount of productivity. On this basis, the analysis of energy consumption, the temperature distribution, composition distribution in solid phase and gas phase were carried out within a cycle.

Key words: adsorption, numerical simulation, experimental validation, carbon dioxide capture, carbon molecular sieve, 13X

摘要：

针对日益严重的温室效应及传统CO₂捕集和储存技术的不足，设计带循环的二阶四塔变压吸附装置捕集电厂烟道气中的二氧化碳，采用炭分子筛作为第一阶二塔处理装置吸附剂，采用13X作为第二阶二塔处理装置的吸附剂。建立上述工艺的数学模型，通过实验验证数学模型和模拟结果的准确性。模拟结果表明，本工艺可以将烟道气中的CO₂（15%）富集为纯度95%的产品气，收率为93.92%，工艺处理量为4.576 mol CO₂·h^-1·kg^-1，能耗为0.847 MJ·（kg CO₂）^-1，通过对比，本工艺具有处理量大、回收率高、纯度高的优点。在此基础上，根据数学模型分析二阶床层在一个周期内的压力变化、温度分布、固相和气相组成分布、能耗组成、生产能力。

关键词: 吸附, 数值模拟, 实验验证, 二氧化碳捕集, 炭分子筛, 13X