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[摘要]：Rapid pyrolysis of three typical Chinese coals, lignite from Inner Mongolia, bituminous from Shenfu coal-field, and anthracite from Guizhou, as well as a petroleum coke were carried out in a drop-style high-frequency furnace. The reactor was induction coil heated and had a very small high-temperature zone, which could restrain secondary conversions of nitrogen products. The effects of temperature and coal rank on conversions of fuel-N to primary nitrogen products (char-N, HCN-N, NH3-N and (tar + N-2)-N) have been investigated. The results showed that, the increasing temperature reduced the yields of char-N and promoted the conversion of fuel-N to N-2. Char-N yields increased, while volatile-N yields decreased as the coal rank increased. In most of the conditions, NH3-N yields were higher than HCN-N yields during rapid pyrolysis of coal. In the case of petroleum coke, NH3-N yields increased gradually with the increasing temperature, but no HCN was detected. We argue that NH3-N can be formed directly through the primary pyrolysis without secondary reactions. Although volatile-N yields of lignite were higher than those of bituminous, yields of (HCN + NH3)-N in volatile-N of lignite were lower than those of bituminous. While the (HCN + NH3)-N yields of anthracite were the lowest of the three coals. Both of the (HCN + NH3)-N yields and (HCN + NH3)-N proportions in volatile-N of petroleum coke were lower than the three coals. (C) 2011 Elsevier Ltd. All rights reserved. |
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