Delayed coking of oil residues

Abstract

This invention relates to petroleum processing, in particular to producing coke with a delayed coking process and to an assembly for trapping the products formed during the coke steaming and cooling processes. Petroleum coke deposits in delayed coking reaction drums. When one drum fills up, the flow of feed into that drum is switched off. The temperature in the switched off drum rises to 420-450° C. To remove coke from the drum, the drum needs to be water-cooled to 60-90° C., but the petroleum vapour products must be removed first and steamed water steam. Low-quality fractionating of the products formed during the steaming and cooling of coke results in losses of petroleum products and in atmospheric pollution.

1 - 2 . (canceled) 
     
     
         3 . A method of delayed coking of petroleum residues, comprising the steps of:
 coking a feedstock, wherein coke is deposited in a coke drum;   fractionating any distillate products in a rectification column into vapour products including light and heavy gas oils and heavy bottoms;   steaming coke with a water steam;   water cooling the coke;   introducing the products of the coke steaming and cooling steps into an absorber equipped with a plurality of mass-exchange assemblies;   fractionating the steaming and cooling products into vapour and liquid phases in the absorber;   producing low-volatility petroleum products from the vapour phase by introducing the heavy bottoms from a bottom part of the absorber into the mass-exchange assembly;   cooling and condensation of the vapour components in a condenser/refrigerator and fractionating the cooling products in a fractionator into gas, petroleum products and water;   wherein the produced heavy gas oil is split into a plurality of flows, wherein a first flow is used as a recirculate and is mixed with the feedstock in the evaporator column prior to coking, wherein a second flow dilutes the products of coke steaming and cooling prior to introducing it into the absorber, wherein a third flow is introduced into a top mass-exchange assembly of the absorber, wherein the heavy bottoms are returned from the bottom part of the absorber into the mass-exchange assembly located in a middle part of the absorber, into a third or fourth mass-exchange assembly, wherein a left-over part of the heavy bottoms from the absorber, as well as the separated petroleum products from the fractionator, are returned into the bottom part of the rectification column.   
     
     
         4 . The method according to  claim 3 , further comprising feeding a wash product including heavy coking gas oil into the condenser/refrigerator.