The invention relates to a continuous
sedimentation process for production of needle
coke. Under the continuous condition of in-out materials, the process carries out
settling separation on an insoluble substance of
quinoline to obtain a qualified light phase of the insoluble substance of the
quinoline. The mixed ratio of an aliphatic
solvent to an
aromatic solvent is (0.6-1.2) to 1; the mixed ratio of a mixed
solvent to soft
coal-
tar asphalt is (0.6-1.2) to 1; the mixed oil is pumped into
settling separation equipment by a pump for the
settling separation; light liquid slowly rises; and after the insoluble substance of the
quinoline reaches the requirement, the light liquid is continuously discharged from the upper part and distilled to obtain refined
asphalt. The continuous
sedimentation process has the advantages that the prior intermittent
sedimentation process is improved into the continuous
sedimentation process, namely the in-out materials are processed under the continuous operating condition. The
continuous operation can simplify operation, reduce equipment, the floor space and the blocking of the equipment, and is favorable for long-period operation of the process.