【作者】 王尚槐； 冯俊小； 赵平；

【Author】 WANG Shanghuai FENG Junxiao ZHAO Ping (University of Science and Technology Beijing)

【机构】 北京科技大学热能工程系； 北京科技大学；

【摘要】 对几种煤基直接还原法(回转窑法、隧道窑法、环形转底炉法和连续炉法)的燃耗进行了对比和分析。其中,隧道窑法燃耗最高,COF连续炉法的燃耗最低。燃耗差别来源于还原工艺、可燃气的燃烬程度、烟气温度、热损失等项。用内配碳还原工艺不需过剩碳,故还原剂的用量最少。在炉内将可燃气体燃烬可获得热量5.57～8.12 GJ/t,它可满足炉料升温和矿石还原所需的热量,出炉烟气温度每降低100℃,可节能1.08～3.90 GJ/t。应在炉子出口处保持适当高的烟温,而在炉膛外充分利用烟气余热,减少热损失,特别是减少蓄热热损失,是降低燃耗的另一重要途径。节约的热量是降低的热损失量的两倍。更多还原

【Abstract】 The coal consumptions of various coal-based direct reduction processes, such as rotary kiln process, tunnel kiln process, rotary hearth funace process and COF continuous furnace process, are compared and analysed. Tunnel kiln process has maximum coal comsumption and COF process has minimum value. The factors affecting coal comsumption are reduction method,degree of complete combustion,flue gas temperature and heat loss etc. Using carbon-bearing pellets needs less reduction agent. Completely post combustion of CO generated in reduction process will release heat energy 5. 57-8. 12 GJ/t, which can meet the energy needs of reduction reaction and temperature rise of pellets. Higher flue gas temperature is necessary for higher out put, however, the heat energy of flue gas must be recovered. One of the main way to save energy is decreasing heat loss, especially decreasing the accumulation heat loss. The saved energy is almost twice of the decreased heat loss.更多还原