Abstract: Method for degassing a storage tank for liquid products containing volatile organic compounds or VOC, in particular petroleum products, comprising a step a) of introducing an aqueous mixture comprising substances able to interact chemically and/or physically with the VOC in the gaseous state inside the tank, which is kept closed, so as to encourage them to pass from the gaseous phase to the liquid phase, and to remain in the liquid phase. Such introduction step being protracted so as to reduce the concentration of the VOC to a predetermined value functional to having an acceptable explosive limit.

Abstract: Method for treating bottom sludge in a storage tank, comprising the step of breaking up the bottom sludge of the tank by the use of one or more jets under pressure. The method is characterized in that it comprises the steps of: monitoring the state of the bottom sludge inside the tank by SONAR means; and adjusting the action of the jets during the breaking-up step according to the effects on the state of the bottom sludge detected by the monitoring by SONAR means.