Patent ID: 7306713

Claim:
A delayed coking process comprising: a) heating a petroleum resid, which is essentially a solid at room temperature, in a first heating zone, to a temperature below coking temperatures wherein it is converted to a pumpable liquid; b) conducting said heated resid to a second heating zone wherein it is heated to an effective coking temperature; c) conducting said heated resid from said second heating zone to a coking zone operating at a temperature between about 410° C. and 475° C. wherein vapor products are collected overhead and coke is formed; d) introducing into said resid at least one substantially metals-free additive that is effective for the formation of substantially free-flowing shot coke, wherein said substantially metals additive is introduced into said resid at a point upstream of said second heating zone, upstream of said coking zone, or both; and e) removing a substantially free-flowing shot coke from the coking zone where said free-flowing shot coke comprises substantially discrete micro-domains having an average size ranging from about 0.5 to about 10 μm.