Liu Hao, Wu Sufang
College of Chemical and Biological Engineering, Zhejiang University Hangzhou 310027 China
RSC Adv. 2022 May 4;12(20):12647-12654. doi: 10.1039/d1ra09250b. eCollection 2022 Apr 22.
The solution of decreasing the decomposition temperature of CaCO and the development of the durability of the CaO-based CO adsorbent are the key issues in reducing the energy consumption and cost of CO capture in calcium looping technology. In this work, BeO with high thermal conductivity was chosen as a dopant of the adsorbent to increase the thermal conductivity properties and decomposition properties of CaCO. The endothermic rate of the nano-CaO-BeO/AlO adsorbent with 15.6 wt% BeO dopant increased by 12.3% compared with that of the nano-CaO/AlO adsorbent at 720 °C, leading to an increase of 10.1% of CaCO decomposition rate. The enhancement of the decomposition rate of the nano-CaO-BeO/AlO adsorbent was significant to lower the regeneration temperature by 50 °C compared with that of the nano-CaO/AlO adsorbent under calcium looping conditions, which made the total average deactivation rate decrease by 21.0% and made the total residual stable carbonation conversion increase by 27.0% in infinite calcium looping cycles. Strengthening the heat transfer inside the adsorbent material can effectively decrease the regeneration temperature, so as to improve the sorption durability.
降低碳酸钙分解温度以及提高氧化钙基二氧化碳吸附剂的耐久性是降低钙循环技术中二氧化碳捕集能耗和成本的关键问题。在本工作中,选择具有高导热率的氧化铍作为吸附剂的掺杂剂,以提高碳酸钙的导热性能和分解性能。在720℃下,掺杂15.6 wt%氧化铍的纳米氧化钙-氧化铍/氧化铝吸附剂的吸热速率比纳米氧化钙/氧化铝吸附剂提高了12.3%,导致碳酸钙分解率提高了10.1%。在钙循环条件下,纳米氧化钙-氧化铍/氧化铝吸附剂分解率的提高对于将再生温度比纳米氧化钙/氧化铝吸附剂降低50℃具有重要意义,这使得在无限次钙循环中总平均失活率降低了21.0%,总残余稳定碳酸化转化率提高了27.0%。增强吸附剂材料内部的传热可以有效降低再生温度,从而提高吸附耐久性。