Effect of coal moisture content on coke’s quality and yields of products during coal carbonization

Abstract

The coal with low moisture during carbonization could not only increase the yield of coke, but also promote the coke quality and reduce the energy consumption. In this paper, the influence of the moisture in the blend coal (1.8%–10.13%) on the product yields and coke quality during coal carbonization were investigated. The results show that the coke yield is increased from 75.90% to 77.16%, and the coke qualities such as coke strength after reaction with CO₂ (CSR), coke reactivity index (CRI), fragmentation index (M25) and abrasion index (M10)) are also improved when the moisture of the blend coal decreases from 10.13% to 1.80 % in a bench scale reactor. Due to the secondary reaction, tar become lighter when the moisture is decreased. In order to further prove the above results, the blend coal with 1.8% and 9%–10% (common moisture used in coke plant) moisture is carbonized in a coke oven with 6 m height, the results show that CRI are 23.4% and 27.3%, CRS are 67.1% and 62.2% under 1.8% and 9%–10% moisture of blend coal. Moreover, the variation of the moisture in blend coal has a limited influence on dust emission at the ascension pipe and the charging car.

Keywords

coking coals / low moisture / carbonization / coke / coke qualities

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