Numerical modelling of a pressurised entrained-flow gasification simulator.

In order to study the gasification process of coal particles, two small scale Entrained-Flow Gasification simulators were developed at the Netherlands Energy Research Foundation (ECN). The Atm. Entrained-Flow Gasification Combustion simulator (AEFGC-simulator) offers the possibility to study gasification and combustion processes exptl. at atm. pressures. With the Pressurized Entrained-Flow Gasification simulator (PEFG-simulator) the conditions during the gasification process at high pressures can be simulated exptl. Both simulators consist of a circular tube with three concentric inlets: two burners and an annular inlet for a co-flow. Coal particles can be inserted through the center burner into the simulator. It is possible to use several gas mixts. up to a pressure of 20 bar (only for the PEFG-simulator) by varying the operational conditions of the burners. To select appropriate exptl. settings, a numerical model was developed to predict the compn. and temp. of the gas phase within the simulators without particles. The model focuses on the mixing and reaction processes within the simulators. The inlet boundary conditions are computed by a sep. combustion code, while the reactions within the simulator are assumed to be diffusion limited. All the important coeffs. are temp. and mixt. dependent. Due to the high concn. of radiating species (CO, CO2 and H2O) gas radiation is important. The absorption coeff. is detd. using the Edwards exponential wide band model. Comparison of the preliminary modeling results at one bar with the model predicts the compn. and temps. at the center axis of the AEFGC-simulator reasonably well, although further research is necessary.