Processing of acid containing hydrocarbons

Abstract

A method for thermally cracking an organic acid containing hydrocarbonaceous feed wherein the feed is first processed in a vaporization step operated under conditions designed to disassociate acid species in the feed prior to passing the feed to a thermal cracking furnace.

1 . A method for thermally cracking in at least one thermal cracking furnace a hydrocarbonaceous feedstock composed of at least one hydrocarbonaceous material, at least one of said hydrocarbonaceous materials containing at least one organic acid species, said method comprising preheating said feedstock to form a preheated stream comprising an initial vaporous phase having an initial chemical composition and an initial liquid phase having an initial chemical composition, passing said preheated stream to a vaporization step in which a portion of said initial liquid phase is vaporized in a manner such that the chemical composition of the total of the vapor leaving said vaporization step is different from said initial chemical composition of said initial vaporous phase and the chemical composition of the remaining liquid leaving said vaporization step is different from said initial chemical composition of said initial liquid phase, carrying out said vaporization step in a manner such that at least some of said at least one organic acid species is disassociated therein, and passing at least part of said vapor leaving said vaporization step to said at least one thermal cracking furnace as at least part of the feed therefore. 
     
     
         2 . The method of  claim 1  wherein said hydrocarbonaceous feedstock has a TAN of at least about 1.0 mg KOH/g feedstock. 
     
     
         3 . The method of  claim 1  wherein said hydrocarbonaceous feedstock has a TAN of at least about 0.5 mg KOH/g feedstock. 
     
     
         4 . The method of  claim 1  wherein said hydrocarbonaceous feedstock is at least one of whole crude oil, condensate, residuum, and mixtures of two or more thereof. 
     
     
         5 . The method of  claim 1  wherein said hydrocarbonaceous feedstock is at least one atmospheric residuum. 
     
     
         6 . The method of  claim 1  wherein said at least one organic acid species includes at least one carboxylic acid, and at least some of said at least one carboxylic acid is disassociated in said vaporization step. 
     
     
         7 . The method of  claim 6  wherein said at least one carboxylic acid includes at least one naphthenic acid species. 
     
     
         8 . The method of  claim 1  wherein said vaporization step employs at least first and second vaporization zones, said first vaporization zone receives said preheated feed stock comprising said initial vaporous phase and said initial liquid phase and at least separates said initial vaporous phase from said initial liquid phase, said separated initial vaporous phase materials are passed from said first vaporization zone to said at least one thermal cracking furnace as feed therefore, said second vaporization zone receives from said first vaporization zone preheated initial liquid phase materials that were not present as vapor in said first vaporization zone and subjects such materials to at least one of heating and mild cracking in said second vaporization zone until a significant amount of such materials in said second vaporization zone are vaporized to form additional gaseous materials and leaving a liquid remainder, and said additional gaseous materials formed in said second vaporization zone are removed there from and passed to said at least one thermal cracking furnace as feed therefore, whereby the chemical composition of said additional gaseous materials formed in said second vaporization zone is different from the chemical composition of said initial vaporous phase, and the chemical composition of said liquid remainder leaving said second vaporization zone is different from the chemical composition of said initial liquid phase. 
     
     
         9 . The method of  claim 8  wherein said initial liquid phase materials in said second vaporization zone are subjected to a temperature in the range of from about 700 to about 1,100 F. 
     
     
         10 . The method of  claim 8  wherein initial liquid phase materials that were not present as vapor in said first vaporization zone are subjected in said second vaporization zone to a temperature in the range of from about 700 to about 1,100 F, and an overall steam to hydrocarbon/acid species ratio of from about 0.1/1 to about 5/1. 
     
     
         11 . The method of  claim 8  wherein said separated initial vaporous phase materials from said first vaporization zone contain at least some organic acid species, said removed additional gaseous materials from said second vaporization zone contain a significant amount of dissociated and non-disassociated organic acid species, said separated initial vaporous phase materials from said first vaporization zone and said removed additional gaseous materials from said second vaporization zone are combined, and the combined stream passed to said at least one thermal cracking furnace. 
     
     
         12 . The method of  claim 11  wherein a significant amount of said at least one organic acid species that were originally in said hydrocarbonaceous feedstock is disassociated or otherwise altered in said vaporization step before transmission to said at least one thermal cracking furnace.