Method for delayed coking of oil residues

Abstract

The invention relates to the petroleum-processing industry, in particular, to a retarded coking process directed to the production of gas oil fractions (light gas oil and two types of heavy gas oil). The method comprises heating a starting stock, feeding same into an evaporator for mixing with recycled material and forming a secondary stock, coking the secondary stock and fractionating the resulting coking products in a rectification column, thereby producing gas, petrol; light and heavy coking gas oils, and bottoms. Heavy coking gas oil is used as the recycled material. The method envisages feeding cooled heavy gas oil to mass-exchange devices in the lower part of the rectification column, and feeding a metered quantity of cooled light gas oil to mass-exchange devices in the upper part of the rectification column. The quantity of cooled light and heavy gas oils which can be fed in changes depending on the required quantity and quality of the light and heavy gas oils and bottoms being produced.

1 - 3 . (canceled) 
     
     
         4 . A method for delayed coking of oil residues, comprising the steps of:
 heating a source of raw material for coking and feeding it into a vaporizer so as to mix with a recirculate in order to form a secondary raw material for coking;   heating the secondary raw material and feeding it into a coking chamber;   feeding any products of the coking from the coking chamber into a rectification column for fractioning so as to obtain gas, gasoline, light and heavy coking gas oil, and bottom liquid;   feeding the heavy coking gas oil that has cooled to a mass-exchange device in a lower part of the rectification column; and   feeding the light coking gas oil that has cooled to a gas-exchange device in an upper portion of the rectification column   
     
     
         5 . The method according to  claim 4 , wherein a quantity of the fed cooled light and heavy coking gas oil changes depending on a required quantity and quality of the obtained light and heavy coking gas oils and bottom liquid. 
     
     
         6 . The method according to  claim 4 , wherein the heavy coking gas oil is used as a recirculate.