Antifoam process for delayed coking
AssigneeAmoco Corporation
InventorShri K. Goyal
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Abstract
An improved delayed coking process using an improved method for adding antifoam materials to the delayed coking process. The process is directed to injecting a polysiloxane antifoam material in mixture with an inert gas in the absence or substantial absence of steam and wherein this mixture is heated and thereafter injected into a delayed coking drum. The process allows improved use of antifoam materials and prevents downstream contamination of process units with silica materials which can be broken down when the polysiloxane antifoam material is contacted with large quantities of steam within the coking drum.
Claims27
In a delayed coking process wherein a heavy feed is passed into a coking drum at coking conditions including a temperature above about 800.degree. F., to form solid coke and vapor products, wherein foaming of hydrocarbons in the coke drum is inhibited by addition of an effective amount of a polysiloxane to the hydrocarbons wherein an improvement comprises adding to the upper portion of the coke drum a mixture comprising polysiloxane and an inert gas wherein the mixture has a substantial absence of steam to substantially reduce thermal degradation of said polysiloxane and is heated up to at least about 400.degree. F. prior to contacting any contents of the coking drum.
In a delayed cooking process wherein a heavy feed is passed into a coking drum at coking conditions including a temperature above about 800.degree. F., to form solid coke and vapor products, wherein foaming of hydrocarbons in the coke drum is inhibited by addition of an effective amount of a polysiloxane having an empirical formula as follows:
- ##STR4## wherein n is up to about 2500 and each R group is independently at least one member selected from the group consisting of methyl, ethyl, propyl, lower alkyl (up to about five carbon atoms) having one or more hydroxy groups, lower alkyl (up to about five carbon atoms) having one or more halogen groups, or phenyl, wherein an improvement comprises adding to the upper portion of the coking drum a mixture comprising said siloxane and an inert gas wherein the mixture has a substantial absence of steam to substantially reduce thermal degradation of said polysiloxane is heated to at least above about 750.degree. F. in a heating zone, and thereafter is discharged from said heating zone into the coking drum and admixed with material in the coking drum.
Dependencies are inferred from the claim text.