The Effects of Operational Parameters on the Transport Phenomena in COREX Melter–Gasifier
The Effects of Operational Parameters on the Transport Phenomena in COREX Melter–Gasifier
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DOI：
10.2355/isijinternational.40.1073
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发表时间：
2000-11
影响因子：
1.8
通讯作者：
Seung Cheol Lee;Myung-Kyun Shin;S. Joo;J. Yoon
中科院分区：
文献类型：
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作者：
Seung Cheol Lee;Myung-Kyun Shin;S. Joo;J. Yoon
利用开发的模拟COREX熔融气化炉的计算程序，研究了操作参数对熔融气化炉内输运现象的影响。研究了床层高度、碳氧比、操作压力和注汽比等参数。随着床层高度的增加，由于气固两相之间有充分的热交换，燃烧区附近的温度也随之升高。然而，由于热交换停留时间的增加，干舷区温度保持不变。操作压力影响煤中焦油的含量。然而，作为压力函数的演化焦油的变化程度并没有大的变化。碳氧比的变化会影响煤的升温速率，固相和气相的传热传质也会发生剧烈变化。燃烧区和干舷区温度受碳氧比变化的影响较大。碳氧比还通过升温速率的变化改变煤的演化速率。从这些考虑出发，为了稳定运行，应该仔细控制C/O比率。研究了在熔融气化炉中注入蒸汽的效果。当蒸汽注入率达到30%时，燃烧区的温度升高。注汽也影响了气相流出物的组成。随着注汽比的增大，CO/CO 2比值降低，而h2 / h2o比值保持不变。
Using a computational code developed for simulating the COREX melter-gasifier, the effects of operational parameters on the transport phenomena in the melter-gasifier were studied. The parameters studied were the bed height, C/O ratio, operating pressure and steam injection ratio. When the bed height was increased, the temperature near the combustion zone also increased due to there being sufficient heat exchange between the gas and solid phase. However, the freeboard zone temperature remained constant due to the increased residence time for heat exchange. Operational pressures affect the rate of tar in the coal. However, the extent of the change in the evolved tar as a function of pressure did not vary severely. The variation in the C/O ratio affected the heating rate of coal followed by a drastic change in the heat and mass transfer of solid and gas phases. The combustion zone and the freeboard zone temperature were changed largely by variations in the C/O ratio. The C/O ratio also changed the evolution rate of the coal by the changes in heating rate. From these considerations, the C/O ratio should be carefully controlled for the stable operation. The effects of steam injection into the melter-gasifier were also studied. Up to a steam injection rate of 30 %, the temperature of the combustion zone increased. Steam injection also affected the effluent composition of the gas phase. When the steam injection ratio was increased, the CO/CO 2 ratio was decreased while H 2 /H 2 O ratio was remained unchanged.