Modeling of Coal char gasification with steam-H2 and steam

摘要

The experiments of Shenfu coal char steam gasification with hydrogen and without hydrogen at 875-975 on ambient pressure °Cwere carried out on a thermogravimetric apparatus. The relationship curves of gasification rate (r=dx/dt) and carbon conversion (x) of steam gasification with hydrogen and without hydrogen were different remarkably. The former gasification kinetics models, such as the random pore model, can't predict the curve of shenfu coal char gasification with H2O/H2, therefore, a gasification kinetics model would be proposed for this gasification with H2O/H2. Based on the random pore model hypothesis, this gasification kinetics model is built through inducing an inhibition factor G (x)=ex(1-x)m to the random pore model. In the expression of model,dx/dt=Aoex(1-x)n√1-Ψ ln(1-x),the value of parameter, n, is linear to the reciprocal of gasification temperature (K). Comparing the experimental data and the curve fitted by this model, it could describe the experimental data of coal char gasification with H2O/H2 mixture gases perfectly and relative coefficients were all above 0.99.