Influence of steam temperature on carbon conversion and product gas composition in entrained coal gasification

In the process of coal gasification steam is expected to increase carbon conversion and hydrogen concentration in the product gas. In some previous investigations of entrained coal gasification, an opposite influence of steam to carbon conversion and product gas composition has been reported. In our experimental investigation of entrained coal gasification steam was produced by hydrogen combustion in a stream of pure oxygen. Influence of steam temperature was realized through comparison of experimental results from two experiments: with and without steam addition. Both experiments were performed with the constant mass flow rates of pulverized coal and steam and with various mass flow rate of oxygen. Hydrogen and carbonmonoxide concentrations decreased with an increase in excess oxygen coefficient, while carbon conversion and carbondioxide concentration increased with an increase in excess oxygen coefficient in the experiment with steam addition. In experiment without steam addition, hydrogen and carbondioxide concentrations decreased with an increase in excess oxygen coefficient, while carbon conversion and carbonmonoxide concentration increased with an increase in excess oxygen coefficient. Hydrogen and carbonmonoxide concentrations and carbon conversion were higher in the experiment with steam addition, while carbondioxide concentration was higher in the experiment without steam addition.