HYDROGEN SULFIDE-CONTAINING OIL TREATMENT PROCESS Russian patent published in 2003 - IPC

FIELD: crude oil treatment. SUBSTANCE: process, which can be applied for treatment of sulfur-bearing oils and gas condensates with high hydrogen sulfide and mercaptan level, consists in multistage separation including blowing off with hydrocarbon gas at the end of separation stage or in a separate desorption column at 25-70 C and pressure 0.1-0.6 MPa until 60-85% hydrogen sulfide is removed. Subsequent post-treatment of oil to remove remaining amounts of hydrogen sulfide is accomplished by adding small amounts of nitrogen-containing basic and/or alkali agent, aqueous or water-alkali solution of salt or variable-valence metal complex as oxidation catalyst and stoichiometric quantities of compressed air or 20-50% hydrogen peroxide aqueous solution as oxidant, after which mixture is maintained at pressure at least 0.15 MPa and temperature 15-70 C for at least 10 min and then separated by reducing pressure to value close to atmospheric. More particularly, nitrogen-containing basic reagent is water-soluble organic amine and/or ammonia and alkali reagent is 20-40% sodium or potassium hydroxide aqueous solution, preferably corresponding to 0.2-2 mole per 1 mole remaining hydrogen sulfide. Metal salt utilized is preferably copper, nickel, cobalt, manganese, or iron chloride or sulfate, and, as complex, copper, nickel, and cobalt complexes with pyrophosphate or ammonia are utilized. Above-named hydrocarbon gas is preliminarily hydrogen sulfide-freed oil-separation gas, preferably used in quantities corresponding to 3-9 cu.m/1 cu.m oil. EFFECT: reduced hydrogen sulfide and mercaptan level at high yield of oil. 8 cl, 1 dwg, 1 tbl, 10 ex