Spirit-based distillers’ grains and red mud synergistically catalyse the steam gasification of anthracite to produce hydrogen-rich synthesis gas

Abstract

In a fixed-bed reactor, spirit-based distillers’ grains (SDGs) and red mud (RM) are used as disposable catalysts for anthracite steam gasification. The material ratio and reaction temperature influences on gasification reaction characteristics were examined. With the use of single- and two-stage fixed-bed reactors, the synergistic catalytic effect and mechanism of three co-gasification reactions were investigated. The results reveal that SDGs and RM produce a synergistic catalytic effect, which improves the gasification activity and hydrogen production efficiency. An increased temperature weakens the synergistic catalytic effect. At a Coal:SDG:RM ratio of 2:3:1, the synergistic catalytic effect is the strongest. Synergistic catalysis mainly occurs because iron, potassium and calcium produce a uniformly dispersed co-melted substance on the coal char surface, which exerts a catalytic effect on the gasification reaction. The catalytic mechanism is as follows: under the action of high temperature and steam, the cyclic transformation of iron, potassium and calcium between the oxidation and reduction states promotes the water-gas shift reaction.