Use of deashed coal as a flushing agent in a coal deashing process

Claim 1

A process for maintaining the fluid-like properties of a heavy phase withdrawn through a withdrawal conduit from a separation zone in a coal deashing process, said separation zone being maintained at elevated temperature and pressure to effect a separation of a feed mixture comprising soluble coal products, insoluble coal products and solvent, said solvent consisting essentially of at least one substance having a critical temperature below 800 degrees F. selected from the group consisting of aromatic hydrocarbons having a single benzene nucleus and normal boiling points below about 310 degrees F., cycloparaffin hydrocarbons having normal boiling points below about 310 degrees F., open chain mono-olefin hydrocarbons having normal boiling points below about 310 degrees F., open chain saturated hydrocarbons having normal boiling points below about 310 degrees F., mono-, di, and tri-open chain amines containing from about 2-8 carbon atoms, carbocyclic amines having a monocyclic structure containing from about 6-9 carbon atoms, heterocyclic amines containing from about 5-9 carbon atoms, and phenols containing from about 6-9 carbon atoms and their homologs, said feed mixture being separated in said separation zone into a light phase and said heavy phase, which comprises: (a) introducing a fluid substance into said withdrawal conduit during periods in which flow of said heavy phase through said conduit is interrupted due to conduit blockage by solids formed from said heavy phase to mix with said solids therein to form a mixture that exhibits fluid-like characteristics; and (b) discharging said mixture formed in step (a) through said withdrawal conduit without the necessity of depressurizing and cooling of said separation zone.