Abstract: A process for the hydrogenation of a liquid hydrocarbon-containing charge material, comprising the steps of: (i) supplying a high temperature high pressure liquid phase hydrogenation reactor with two separately and indirectly heated charge streams, (a) a primary charge stream comprising liquid hydrocarbon oils, oil residues, syncrudes, tars or pitches and optionally coal, and hydrogen-containing gas, and (b) a directly heated secondary gaseous charge stream comprising hydrogen-containing gas, and combining said indirectly heated primary charge stream and said indirectly and directly heated secondary charge stream prior to said liquid phase hydrogenation reactor, hydrogenating the combined streams to produce a hydrogenation product and separating the hydrogenation product in a hot separator to give a hot separator head product; wherein said indirectly heated primary and secondary charge streams are heated by separate heat exchange means by heat exchange with said hot separator head product, and said secondary