Investigations in High Temperature Catalytic Gas Cleaning for Pressurized Gasification Processes

Abstract

One of the main paths for the development of thermochemical conversion processes involve systems with enhanced process pressures; to increase the overall process efficiency but also to improve the environmental performance of the system. Thus there is a need for fundamental experimental knowledge on chemical gas cleanup at elevated pressures.

A flexible and easy to operate pressurized apparatus has been installed for investigations in high temperature gas cleaning by means of thermal and catalytic or chemical procedures. In the current study tar decomposition of a pyrolysis gas from biomass fuels was investigated. A semi continuos fuel feeding concept allows a very constant formation of a gas product at 700 °C. The gas product is subsequently introduced into a fixed bed secondary reactor where the actual gas cleanup may take place. In this study two different catalysts were used as fixed bed material in this secondary reactor: a Swedish dolomite and a commercial nickel-based catalyst. Tests were performed at cracking temperatures between 800–900 °C and at pressures between 1–20 bars.

Novel technical solutions make the test rig an advanced and versatile platform for thermochemical conversion studies at high temperatures and at enhanced pressures.