Abstract This study investigates the contribution of single coal in blends on the properties of the char produced. Three kinds of coals with varying rank and caking ability were used for the preparation of the chars at 1150 °C in muffle furnace. Char reactivity towards carbon dioxide (CRI) and char strength after reaction (CSR) were tested through the fixed-bed reactor in a laboratory scale and the tumbler, respectively. X-ray diffraction (XRD), scanning electron microscope (SEM), and nitrogen adsorption test were applied to obtain the information for the chemical and physical structures of the char. The study results show that the CRI of char increases with the increase of subbituminous coal content in blends for its role in increasing the surface area and decreasing the crystallite height (Lc) of the chars; the increase of fat coal content in coal blends causes the decrease of the CRI of chars for its contribution to the more ordered crystallite structure and less surface area. The contribution of single coal property in blends to the CSR of chars is just contrary compared to its contribution to the CRI of the chars. Coal blends with high volatile yield and low GR.I value would cause higher surface area and lower crystallite height of char. The CRI of the char can be well predicted by GR.I value and volatile yield of the coal blends quantitatively: CRI ( % ) = -0 .029 G R . I + 1.995 V daf − 57.937 , which is of certain theoretical guiding significance for gasification of char from coal blends.

中文翻译：

---

单一煤质对混炼焦炭结构和反应性变化的贡献

摘要 本研究调查了混合煤中单一煤对所产生焦炭特性的影响。使用不同等级和粘结能力的三种煤在 1150 °C 的马弗炉中制备焦炭。分别通过实验室规模的固定床反应器和滚筒测试炭对二氧化碳的反应性 (CRI) 和反应后炭强度 (CSR)。应用 X 射线衍射 (XRD)、扫描电子显微镜 (SEM) 和氮吸附试验来获取炭的化学和物理结构信息。研究结果表明，焦炭的 CRI 随混合物中亚烟煤含量的增加而增加，因为它具有增加焦炭表面积和降低焦炭晶粒高度 (Lc) 的作用；混煤中脂肪煤含量的增加导致炭的 CRI 降低，因为它有助于更​​有序的微晶结构和更小的表面积。混合煤中单一煤属性对焦炭 CSR 的贡献与其对焦炭 CRI 的贡献相反。具有高挥发分产率和低 GR.I 值的煤混合物会导致炭的表面积更大和微晶高度更低。炭的 CRI 可以通过 GR.I 值和混合煤的挥发物产率定量预测：CRI (%) = -0 .029 GR。I + 1.995 V daf − 57.937 ，对煤混煤气化具有一定的理论指导意义。混合煤中单一煤属性对焦炭 CSR 的贡献与其对焦炭 CRI 的贡献相反。具有高挥发分产率和低 GR.I 值的煤混合物会导致炭的表面积更大和微晶高度更低。炭的 CRI 可以通过 GR.I 值和混合煤的挥发物产率定量预测：CRI (%) = -0 .029 GR。I + 1.995 V daf − 57.937 ，对煤混煤气化具有一定的理论指导意义。混合煤中单一煤属性对焦炭 CSR 的贡献与其对焦炭 CRI 的贡献相反。具有高挥发分产率和低 GR.I 值的煤混合物会导致炭的表面积更大和微晶高度更低。炭的 CRI 可以通过 GR.I 值和混合煤的挥发物产率定量预测：CRI (%) = -0 .029 GR。I + 1.995 V daf − 57.937 ，对煤混煤气化具有一定的理论指导意义。混合煤的 I 值和挥发分产量：CRI (%) = -0 .029 GR。I + 1.995 V daf − 57.937 ，对煤混煤气化具有一定的理论指导意义。混合煤的 I 值和挥发分产量：CRI (%) = -0 .029 GR。I + 1.995 V daf − 57.937 ，对煤混煤气化具有一定的理论指导意义。