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%.