Patent ID: 7374665

Claim:
A method of increasing the capacity of a delayed coking unit using a delayed coker feedstock having less than 250 wppm dispersed metals content and greater than 5.24 API gravity, the method being to shorten the cycle time of the unit by the steps comprising: selecting one or more first delayed coker feedstocks, each having less than about 250 wppm dispersed metals content and greater than about 5.24 API gravity; selecting one or more second delayed coker feedstocks and blending said one or more second delayed coker feedstocks into said one or more first delayed coker feedstocks so that the total dispersed metals content of the blended feedstocks will be greater than about 250 wppm and the API gravity will be less than about 5.24; heating said blend of feedstocks to a temperature from about 70° C. to about 500° C.; conducting said heated blend of feedstocks to a coker furnace wherein the blend of feedstocks is heated to delayed coking temperatures; conducting said heated blend of feedstocks to a coker drum wherein vapor products are collected overhead and a free-flowing solid shot coke product is produced, quenching the coke with water and draining the free-flowing shot coke product with interstitial water from the coker drum by unheading the drum and permitting the shot coke product to pour out of the drum.