Study of possibilities and some problems of using cane residues as fuel in a gas turbine for power generation in the sugar industry

Sammanfattning: The potential of cane residuals as a source of energy could help many developing countries to improve their balance of payments by decreasing fossil fuels imports and increasing the electrical power production. A substantial increase of the electricity output in the sugar industry could be achieved by using a combined gas turbine/steam turbine integrated with gasifier supplying combustible gas to the gas turbine combustor. The problem is to find a way to avoid those ash-forming elements in the solid fuel that cause erosion, corrosion and deposits in the gas turbine. A method for avoiding excessive amounts of alkali compounds and particles in producer gas from gasification of cane residues has been studied and evaluated. Powderised cane residue is gasified in a cyclone gasifier. The cyclone gasifier works as a particle separator as well. The advantage with this technique is that the gasification temperature might be kept at a level where the volatilisation of corrosive elements such as sodium and potassium will not occur which could be separated from the product gas in the cyclone. A comparative study between the cyclone gasifier and a bench-scale fluidised bed gasifier have been conducted to evaluate which gasification process is most attractive as regards alkali separation/retention, and to try to elucidate the mechanisms responsible for the retention.