利用能有效避免二次转化反应的高频炉热解装置对3种不同变质程度的煤进行了600～1200℃条件下的快速热解,考察了在煤热解最初阶段焦产率、焦-C产率、热解气产率,热解气4种主要组分H<,2>、CO、CH<,4>和CO<,2>的比例以及热解气热值随煤阶和热解温度的变化规律.结果表明,焦的产率和焦一C的产率均随煤阶的升高而升高,热解气的产率随煤阶的升高而降低;热解温度的提高能显著降低煤焦和焦一C的产率并提高热解气的产率.热解气组分以H<,2>和CO为主,CH<,4>和CO<,2>的含量较低;随着温度的升高,H<,2>和CO的含量升高,CH<,4>和CO<,2>的含量下降.热解气中H<,2>+CO的含量以及H<,2>/CO的比值均随着温度的升高而升高.烟煤和无烟煤热解气热值均随着温度的升高而降低,褐煤热解气热值则先上升后下降.%The rapid pyrolysis of 3 different ranks of coals, including lignite from Inner Mongolia,bituminous from Shenfu coalfield, and anthracite from Guizhou, has been carried out in a high-frequency furnace which could sharply reduce the secondary reactions. The pyrolysis temperatures were ranged from 600℃ to 1200℃ with an interval of 100℃. The effects of coal rank and temperature on the yields of char,char-C, and pyrolysis gas, as well as the percentages of H2, CO, CH4, and CO2 in the pyrolysis gas produced from the primary stage of pyrolysis were investigated. Results show that both of the yields of char and char-C increase, while the yield of pyrolysis gas decreases as the coal rank increases. The yields of char and char-C decrease, and the yield of pyrolysis gas increases with the increasing temperature. The char-C yield of lignite can reach a level lower than 50％ at the temperature of 1200℃. H2 and CO are the main components of the pyrolysis gas, while the contents of CH4 and CO2 are much lower. As the temperature increases, the contents of H2 and CO increase, and the contents of CH4 and CO2 decrease. The contents of H2 +CO in pyrolysis gas increase with the increasing temperature. The H2 +CO contents from 3 coals are all higher than 90％ at the temperature of 1200℃. The H2/CO ratio of pyrolysis gas also increases as the temperature increases. Both the H2 +CO contents and H2/CO ratio in pyrolysis gas from 3 coals are in the order of anthracite＞lignite＞bituminous. The low heating values of pyrolysis gas from all the 3 coals are higher than 11 MJ · m-3. As the pyrolysis temperature increases, the low heating values of pyrolysis gas of bituminous and anthracite decrease, while the heating values of pyrolysis gas of lignite have a peak value at the temperature about 1000℃.
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