Oily Sludge

Every refinery generates oily hazardous solids during the normal day-to-day operations. The oily solids are actually the accumulation of settled and suspended solids in various vessels, such as storage tanks, sumps, and process sewer lines. These oily solids contain crude oil, various forms of grit, dirt, salts and water.

The accumulation of solids in storage tanks reduces valuable storage space and may also interfere with the normal function of the vessel. As such, it is necessary to periodically remove these oily solids to recover storage space, improve functionality and permit periodic internal inspections.

Once the oily solids are removed they must be disposed of in accordance with local regulations. The cost of disposal is relatively high and the impact of these oily solids on the environment may be harmful, if not done properly. The annual mass of solids generated at a typical 250,000 BPD refinery is approximately 1,400 tons of dry matter.

Veolia Water currently provides this solution in over 20 refineries. Total annual oily solids processing volumes are in excess of 3.9 MBPY.

VWNA offers four alternatives for oily solids management:

three-phase centrifugation with solids disposal
three-phase centrifugation with solids injection to the coker quench cycle
three-phase centrifugation with solids converted to a cement kiln fuel or coker feed
three-phase centrifugation, followed by thermal desorption, hazardous waste delisting and industrial land filling