The steam-gasification reaction characteristics of coal char was studied in a drop tube furnace (DTF). The effects of various factors, such as coal type, gasification temperature and mass ratio of steam to char(steam/char ratio) on the properties of gas products and carbon conversion had been investigated. The experiment temperatures were1100, 1200, 1300 and 1400℃, steam/char ratios 0.4:1, 0.6:1 and 1:1, respectively. The results showed that, for all coal char studied, H2 content in gaseous products was the largest and CH4 content did the smallest. The char from coal with different coal ranks, change of gasification temperature and steam/char ratio had effects on gas composition and carbon conversion for DTF steam-gasification. At steam/char ratio of 0.4:1, 0.6:1 and 1:1, for Shen-fu’ and Bei-su’char, CO and H2 yield increased continuously and H2/CO ratio decreased gradually when gasification temperature went up. The carbon conversion showed an increasing tendency with temperature increased. At gasification temperature higher than 1200℃, the change of carbon conversion of Shen-fu’ and Bei-su’char was not bigger 5%, although steam/char ratio increased from 0.4:1 to 0.6:1. But the ratio increased from 0.6:1 to 1:1, the carbon conversion of Bei-su’char had a little decreasing, in contrast, for Shen-fu’char the increase of carbon conversion was higher than 15%.%在滴管炉内对煤焦与水蒸气气化反应进行了实验研究，考察了煤阶、气化温度、水蒸气与进料煤焦质量比(气焦比)对气化气体产物释放特性以及煤焦转化率的影响。实验温度为1100、1200、1300和1400℃，气焦比分别为0.4：1、0.6：1和1：1。研究发现：滴管炉内不同煤焦的水蒸气气化气体产物以H2含量最高，CH4含量最低。不同煤阶热解焦、气化温度以及气焦比的变化影响滴管炉内水蒸气气化产物气体组成和转化率的高低。随气化温度的升高，神府煤焦和北宿煤焦气化气体产物中H2和CO产率不断增大，H2/CO的比值则逐渐减小，碳转化率有不断增加的趋势。在气化温度大于1200℃的条件下，当气焦比从0.4：1增至0.6：1，神府煤焦和北宿煤焦的碳转化率变化幅度不大（5%以内）；当气焦比从0.6：1增至1：1，北宿煤焦的碳转化率略微降低，而神府煤焦的碳转化率增幅则在15%以上。
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