CO_2煅烧气氛下合成钙基吸收剂的循环反应特性试验

Experiment of the Cyclic Reaction Characteristics of Synthesized Calcium-based Absorbent in the CO_2 Calcination Atmosphere

在热重分析仪内研究了CO2煅烧气氛对新型CaO/MgO(75 wt%/25 wt%)和CaO/Ca9Al6O18(75 wt%/25 wt%)吸收剂循环反应特性的影响。结果表明:两种新型合成吸收剂在CO2气氛下的循环转化率和循环稳定性均明显高于常见的吸收剂。在3种不同煅烧温度下,CO2煅烧气氛下的两种吸收剂的循环转化率均明显高于N2气氛:对于吸收剂CaO/MgO,当煅烧温度为900℃时,CO2气氛下12次循环中的最大循环转化率比N2气氛下高7%;对于吸收剂CaO/Ca9Al6O18,当煅烧温度为900℃时,CO2气氛下12次循环中的最大循环转化率比N2气氛下高25%。在CO2煅烧气氛下,煅烧温度对CaO/MgO吸收剂循环稳定性的影响不大。CaO/Ca9Al6O18吸收剂的循环稳定性和循环转化率都随着煅烧温度的升高而降低。CaO/Ca9Al6O18吸收剂在N2煅烧气氛下发生了自活化。CO2煅烧气氛对两种合成吸收剂循环转化率的影响主要体现在化学反应控制阶段。

In a thermogravimetric analyzer,studied was the influence of the CO 2 calcination atmosphere on the cyclic reaction characteristics of the novel CaO / MgO( 75wt% /25wt%) and CaO / Ca 9 Al 6 O 18( 75 wt % /25 wt %) absorbent. It has been found that both cyclic conversion rate and stability of two kinds of the newly synthesized absorbent in the CO 2 atmosphere are obviously higher than those of the commonly-seen absorbents. At three different calcination temperatures,the cyclic conversion rates of two kinds of the above-mentioned absorbent are conspicuously higher than those in the nitrogen atmosphere: for the absorbent CaO / MgO,when the calcination temperature is 900 ℃,the maximum cyclic conversion rate during 12 cycles in the CO 2 atmosphere is 7% higher than that in the nitrogen atmosphere. For the absorbent CaO / Ca 9 Al 6 O 18,at the same calcination temperature of 900 ℃,the above-mentioned maximum conversion rate is 25% higher than that in the nitrogen atmosphere. In the CO 2 calcination atmosphere,the calcination temperature has little influence on the cyclic stability of the CaO / MgO absorbent. The cyclic stability and conversion rate of the CaO / Ca 9 Al 6 O 18 absorbent will decrease with a rise of the calcination temperature. The CaO / Ca 9 Al 6 O 18 absorbent produces a self activation in the nitrogen calcination atmosphere. The influence of the carbon dioxide calcination atmosphere on the cyclic conversion rates of two kinds of the synthesized absorbent is mainly reflected in the chemical reaction control stage.