循环热载体无烟燃烧技术的试验研究

Methane Nonflame Combustion in Molten Salt Using CuO Catalyst

提出了一个基于熔融盐循环热载体的无烟燃烧技术 ,即把一个燃烧过程分为氧化剂生成和燃料燃烧两个步骤进行 ,燃烧过程能使助燃空气中的N2 和燃烧产生的CO2 在一套反应装置中进行分离 ,得到较高纯度的N2 和CO2 ,N2 可回收利用 ,CO2 则可捕集起来安全封存。整个燃烧过程避免了向大气排放有害气体 ;以CuO为催化剂 ,对CH4在Li2 CO3 -K2 CO3 -Na2 SO4熔盐体系中的熔融燃烧过程进行的试验研究结果表明 ,CH4能在该熔融盐体系中能完成无烟燃烧过程并放出热 ,失去晶格氧的CuO能与空气反应重新恢复其晶格氧 ,气相色谱分析结果显示 ,理想的反应条件下 ,得到的N2 的纯度为 99 3%以上 ,CO2 的纯度为 95 1%以上。

A nonflame combustion technology using thermal cyclic carrier of molten salt introduced in this paper is developed based on the knowledge of energy chemistry,fuel cell and combustion. In this technology,a whole combustion is divided into two steps,i.e. section of producing oxide and section of combustion. In the first step,oxygen is separated form air,and pure N_2 is simultaneously left which is easily recovered. In the other step,fuels react with oxides formed in the first step,and at the same time,thermal energy,CO_2 and H_2O are produced. The CO_2 is easily separated from water vapour and captured. There are theoretically no environmentally-unfriendly gases such as CO_2,NO_x and SO_2 discharged in the whole combustion process. A typical nonflame combustion system using Li_2CO_3+K_2CO_3+Na_2SO_4 as molten salt system,CH_4 as fuel,CuO as catalyst was experimentally investigated. Experimental results show that the combustion process proceeded as theoretically analyzed,and high concentration CO_2 of 77.0%～95.0% and N_2 of 91.9%～99.3% were obtained. The high concentration of CO_2 is favorable for capturing and storing subsequently. So,the potential of reducing CO_2 emissions of this nonflame combustion technology is huge.