The embodiments of the present invention are characterized by degasifying a portion of a gas and slurry mixture in a three-phase slurry process and lowering the solids content of the degassed slurry portion to below about 20 wt %. The degassed and lowered solids content slurry portion is then introduced into a fines separation device for separation and removal of fines. The foregoing procedure has been found to increase the effectiveness of the fines separation device.