Reduction Mechanism of Composite Consisted of Coal and Hematite Ore by Volatile Matter at 700–1100 K
Reduction Mechanism of Composite Consisted of Coal and Hematite Ore by Volatile Matter at 700–1100 K
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700~1100 K 煤与赤铁矿复合物挥发分还原机理
DOI：
10.2355/isijinternational.55.1188
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发表时间：
2015
影响因子：
1.8
通讯作者：
E. Kasai
中科院分区：
文献类型：
--
作者：
Yuki Takyu;T. Murakami;S. Son;E. Kasai
为减缓全球变暖，钢铁行业为减少二氧化碳气体排放做出了努力。利用碳质材料和铁矿石组成的复合材料有望成为解决该问题的有效途径。碳质材料中的挥发物有可能通过降低还原温度来减少排放。在这项研究中，从根本上检验了煤/赤铁矿矿石复合物中挥发性物质的减少。选择不同种类的煤作为碳质材料样品。使用所制备的复合材料进行还原实验，在Ar–5%N 2 气流下将加热速率改变为0.08、0.17和0.33 K/s，直至温度达到1 473 K。分析出口气体成分，并用结果计算减少程度。赤铁矿矿石的还原程度最初随煤中挥发分含量的增加而增加。然而，超过某一点后，煤挥发分含量的进一步增加并没有使还原程度发生显着变化。对于所评估的煤，产生的瓦斯的数量和类型彼此没有不同。 H 2 气体似乎通过烃类气体的分解与固体碳一起形成。这些气体和固体碳可能有助于减少。此外，通过降低加热速率，在反应早期促进了H 2 的还原。数据表明，控制加热速率是促进低温还原的一种可能方法。
the drive to mitigate global warming, the iron and steel industry has made efforts to reduce carbon dioxide gas emissions. Utilization of a composite material consisting of carbonaceous material and iron ore is expected to be an effective way to solve the issue. Volatile matters in carbonaceous materials have a potential to reduce emissions by lowering the reduction temperature. In this study, the reduction by volatile matter in a coal/hematite ore composite was fundamentally exam-ined. Different kinds of coal were chosen as carbonaceous material samples. The reduction experiment using the prepared composites was conducted by varying the heating rate as 0.08, 0.17, and 0.33 K/s, up to a temperature of 1 473 K under Ar–5%N 2 gas flow. The outlet gas composition was analyzed and the results were used to calculate the reduction degree. Reduction degree of hematite ore initially increases with increasing content of volatile matter in coal. However, beyond a certain point, further increase in the volatile matter content of the coal did not give a significant change in the reduction degree. For the evaluated coals, the amounts and types of gases generated are not different each other. H 2 gas seems to form together with solid carbon via decomposition of hydrocarbon gases. Such gases and solid carbon may contribute to the reduction. Moreover, reduction by H 2 was promoted in the early stage of the reactions by decreasing heating rate. The data indicate that control of the heating rate is a possible way to promote reduction at low temperature.