摘要
采用流化床反应器并以水蒸气作为汽化-流化介质,研究了800～950℃内以Fe_2O_3为载氧体的煤化学链燃烧循环反应特性。实验表明,气态产物CO_2的体积浓度(干基)随温度单调递增;CO、CH_4的浓度在反应时间内呈单峰特性且随温度单调递减,CH_4浓度值高于CO;H_2被载氧体完全氧化。载氧体与水煤气化产物在温度高于850℃体现了高的反应活性,CO_2干基浓度接近95%。反应器温度900℃时,气态产物CO_2体积浓度随循环数而逐渐降低,CO、CH_4浓度增加。
Chemical-looping combustion （CLC） is an indirect combustion technology with inherent separation of the greenhouse gas CO2. The reactivity of using Fe2O3 as an oxygen carrier during chemical-looping combustion of coal has been investigated experimentally at 800-950℃ in the present work. The experiments were carried out in a fluidized bed, where the steam acts as the gasification-fluidization medium. Coal gasification and the reduction of oxygen carrier with the water gas take place simultaneously in the reactor. The oxygen carrier particles exhibit high reactivity above 850℃, and the dry basis concentration of CO2 in the exit gas of the reactor is nearly 95%. The flue gas composition as a function of the reactor temperature, reaction time and cyclic reduction number are discussed. At 800-950℃, the dry basis concentration of CO2 in the flue gas presents a monotonously increasing trend, whereas the dry basis concentration of CO and CH4 decreases monotonously, the hydrogen is oxidized completely by Fe2O3-based oxygen carriers. The concentration of CO and CH4 in the exhaust as a function of cyclic reduction number presents a para-eurve characteristic at 900℃. With the increase of cyclic reduction number, the dry basis concentration of CO2 decreases, while the dry basis concentration of CO and CH4 increase. Moreover, the peak value of the CO concentration is less than the value of CH4.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2009年第7期1249-1252,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金项目(No.90610016)
国家重点基础研究发展规划基金项目(No 2006CB20030201
No.2006CB705806)
国家863高技术基金项目(No.2006AA05Z318)
关键词
化学链燃烧
Fe2O3载氧体
CO2分离
煤气化
流化床反应器
chemical-looping combustion
Fe2Oa oxygen carrier
COs separation
coal gasification
fluidized bed reactor
