PROCESS FOR HEATING SOLIDS IN A TRANSFER LINE

摘要

Oil shale, coal, inert heat transfer material and other carbon-containing solids of varying sizes are preheated with a gas in a transfer line by first separating the solids into a plurality of size fractions and then separately introducing the size fractions into the transfer line at predetermined distances from the transfer line inlet. The predetermined distances are inversely related to the size of the particles comprising each fraction of solids so that the fraction of solids containing the largest particles is produced nearest to the gas inlet and the fraction of solids containing the smallest particles is introduced at a point furthest away from the transfer line inlet. Normally, solids withdrawn from the transfer line will have been heated to a temperature below which any liquids or gases evolve and are ready for further processing in downstream conversion units such as oil shale retorts, coal gasifers and the like.