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Tank bottoms
Tank bottom sludges contain a high percentage of oil that can be recovered as valuable products; not to mention the economic and environmental aspects of reduced waste volumes. These products are generally difficult to handle due to their high solids and emulsion content and high viscosity. The slop oils can vary in their composition and contain 10-70 % oil, 30-90 % water and 5-20 % solids. The oil viscosity can be very high and reach values of up to 600 cSt / 50°C. The specific gravity of the oil (oil density) can vary from 0.8 to 0.96 g / ml.
Furthermore, low pH values and high chloride concentrations are additional challenges, and factors such as abrasive particles (sand), organic solids and the presence of asphaltenes must also be taken into account. If this sludge is not treated on-site, it must either be incinerated or sent to specialized treatment plants for further processing / disposal. Since this waste is also environmentally hazardous and difficult to transport, disposal for the oil industry is costly, driving a high demand for services that are able to process tank bottom sludge efficiently. Tank bottom oil treatment also recovers hydrocarbons that would otherwise be lost, which creates an additional value.
As an alternative to the cost-intensive disposal of slop oil, GEA has developed a method to recycle the oils in an environmentally friendly way. The advantages for customers: added value through 80-95 % recovery of salable hydrocarbons and reduction of the total disposal costs. The technical solution for recovering the valuable oil and minimizing its environmental impact is to combine mechanical separation technology in several stages with heating and the improvement of the separation effect by chemicals.
