Oil shale retorting process with raw shale preheat prior to pyrolysis

摘要

Disclosed is an improved process for retorting oil shale in a staged turbulent bed retort wherein the raw shale feed particles are classified and deaerated into first and second fractions, said first fraction containing substantially only shale particles above about 25 mesh. The first fraction is then preheated with hot shale fines in a dilute phase lift pipe prior to retorting.