Mechanical equipment in the oil processing industry can operate for years between shutdowns. During this time there is often a tendency for scale, debris and sludges to form within this equipment. During the shutdowns these fouling materials have to be removed before mechanical work or even entry can be allowed. Detergents have been developed to speed the cleaning and decontamination of equipment.
These detergents alone or in combination with other chemicals such as oxidizing agents have reduced the need for caustic and acid washing of refinery equipment. Detergents, however, can interfere with the
subsequent reprocessing of the oil removed. And they may have adverse effects on the refinery's water effluent system. Several criteria for detergent selection and field test methods are presented.