Study on the Predicting Technique of Ash Deposition Tendency in the Entrained-Flow Coal Gasifier. 2nd Report. The Analytical Results of Ash Deposition Tendency in a 2T/D Coal Gasifier Using Numerical Simulation Code with Ash Adhension Model.

Abstract

The phenomenon of coal ash deposition on the walls is observed in an entrained-flow coal gasifier. The deposits interfere with heat transfer, and if they are heavy, they not only interfere with operation but also cause unplanned shutdowns of a gasifier. In order to commercialize IGCC power plant, ash adhesion behavior in a coal gasifier should be predicted when operational conditions of a gasifier or coal types might be changed. CRIEPI has been conducting study on the predicting technique of mineral matter deposition behavior in a coal gasifier. In this study, ash sticking/rebounding discrimination model based on ash liquid phase ratio was evolved. This model was introduced into numerical simulation code which had been developed by CRIEPI. Numerical simulation of ash behavior has been conducted for a 2/day coal gasifier and the ash deposition tendencies in a gasifier were evaluated. Numerical analysis results were in good agreement with experimental results of ash deposition tendency in a 2/day coal gasifier.