Olefin production utilizing condensate feedstock
View Patent ↗A method for utilizing natural gas condensate as a feedstock for an olefin production plant wherein the feedstock is subjected to vaporization and separation conditions that remove light hydrocarbons from the condensate for thermal cracking in the plant, and leave liquid distillate for separate recovery.
1. In a method for operating an olefin production plant that employs a pyrolysis furnace to thermally crack hydrocarbon materials for the subsequent processing of said cracked materials in said plant, said furnace having in its interior at least a convection heating section and a separate radiant heating section, said radiant heating section being employed for said cracking, the improvement comprising providing natural gas condensate liquid as the primary feedstock to said furnace, said feedstock consisting essentially of at least one distillate and hydrocarbons that boil at temperatures lower than said at least one distillate, (1) directing said feedstock to a first zone of a vaporization unit and separating a portion of said feedstock in said first zone into a first vapor stream consisting essentially of only hydrocarbons that boil at a temperature lower than said at least one distillate while leaving a first liquid stream consisting essentially of said at least one distillate and remaining hydrocarbons that boil at a temperature lower than said at least one distillate, and (2) passing said first liquid stream to a second zone of said vaporization unit, (3) contacting said first liquid stream with steam in said second zone so that said first liquid stream mixes with said steam to produce a second vapor stream consisting essentially of only remaining hydrocarbons that boil at temperatures lower than said at least one distillate, and a second liquid stream consisting essentially of only said at least one distillate, (4) passing at least one of said first vapor stream and said second vapor stream to said cracking furnace, and (5) recovering said second liquid stream containing said at least one distillate from said second zone and disposing of said second liquid stream other than in said cracking furnace.
2. The method of claim 1 wherein said recovered liquid hydrocarbons are added to a distillate pool.
3. The method of claim 1 wherein said feedstock boils in a temperature range of from about 100 to about 650 F, and contains A) at least one of naphtha, and B) at least one distillate selected from the group consisting of kerosene, diesel fuel, and gas oil.
4. The method of claim 3 wherein said feedstock is heated to vaporize essentially all said naphtha.
5. The method of claim 4 wherein said feedstock is heated to a temperature of from about 150 to about 450 F.
6. The method of claim 3 wherein said feedstock is heated to vaporize a significant portion of said naphtha but leaving finite amounts of naphtha in the liquid state and mixed with said at least one liquid distillate.
7. The method of claim 6 wherein said feedstock is heated to a temperature of from about 200 to about 450 F.