Oil shale upgrading process

摘要

A size fraction of oil shale is upgraded by separating the shale into a first low density fraction containing particles relatively rich in kerogen and a first high density fraction containing particles relatively lean in kerogen, crushing the first low density fraction to produce smaller particles, separating the smaller particles into a second low density fraction and a second high density fraction and recovering the second low density fraction as high grade oil shale rich in kerogen.