FIELD: oil pollution removal. SUBSTANCE: cleaning is effected by detergent composition containing, wt %: one or several surfactants 5.0-12.0, electrolyte 1.0-8.0, and soda ash Ц to 100 or composition with the same components wherein 2.0-8.0 of soda ash is substituted by corrosion inhibitor. Detergent composition is prepared by dissolving detergent in water preheated to 20-65 C to concentration 1.0-3.5% and keeping this temperature during cleaning process followed by pumping out detergent solution with removed hydrocarbons into the same tank, from which detergent solution is transferred into cleaning zone. Detergent-hydrocarbon mixture is then settled in the same tank. EFFECT: enhanced cleaning efficiency and reduced process cost and cleaning time. 3 ex
