A New Generation of Refractories to Enable Gasifier Fuel Flexibility

Abstract

Gasification is used by industry to convert low cost carbon into materials for producing electricity and chemical products such as fertilizer, plastics, and Fischer-Tropsch liquids. It is considered a critical technology in the success of the DOE’s Near Zero Emissions Advanced Fossil Fuel Power Plants, could play a key role in defining long-term energy security in both power and liquid fuels, and is considered a leading candidate for H2 production in a hydrogen based economy. Molten slag originating from mineral impurities in the carbon feedstock is of concern to slagging gasifier operation, with some gasifiers generating over 100 tons per day. Molten slag attacks and wears away the internal lining of the gasifier vessel by two major mechanisms, chemical dissolution and spalling. The main component in current refractory linings is chrome oxide. NETL is researching new types of refractory materials as an alternative to the high chrome oxide refractories currently used, with the goal of improving performance and providing a predictable service life. It has previously developed and patented the use of phosphate additives to improve the wear and spalling resistance of high chrome oxide refractories, and is exploring chrome and non-chrome oxide materials through laboratory testing and the use of thermodynamic modeling. In this paper, the results of a different additive (carbon) was evaluated by laboratory testing and found to improve slag penetration resistance. Data on this evaluation will be presented, and is proposed as a means of improving the molten slag wear resistance of the refractory. The use of it as a means of improving refractory service life in the field is patent pending.