The term "Oil Sludge" is used, in general, to designate waste generated due to storage of crude/products, containing mixtures of Oil, water and solids. The ratio of different phases, fluctuates depending upon the origin of the crude oil, or location of the accumulation.

a) Sludge from Crude Oil b) Sludge from products

Sludge from Refineries and installations can be further classified as

1) Tank Bottom Sludges, 2) Lagoon Sludges, 3) Landfills

Oily Sludges are categorized as Hazardous Wastes under the Environment Protection Act and Hazardous Wastes Handling Rules. These sludges cannot be disposed off as landfill, even if they are de-oiled unless they are totally remediated.

What are the treatment options?

Low Oil content sludges in refineries and depots
Solution: Treatment of sludge at the site:

The sludges containing recoverable oil less than 40% are considered as low oil content sludges. Usually the product sludges accumulated at the installations, terminals and depots come under this category. These sludges have to be treated and made harmless before disposal. We have developed our Enhanced Bio remediation Process for this purpose.


High Oil content sludges in refineries
Solution: Recovery of useful oil and treatment of solids and water:

Generally the refinery sludges contain oil content more than 40% and several methods are deployed to separate the oil, water and solids. In this process, the recovered oil is pumped back into the refinery process, while the solids and water are supposed to be treated before disposal.

The equipment used for extraction of oil include decanters, tricanters, centrifuges and hydrocyclones as the per the process design. Large quantities of solvents are needed for these operations and usually refineries provide the same. The cost of plant, machinery, solvents, and operations are very high for all these types of process. The recovery method is adopted only if the sludge quantities are in thousands of cubic metres. In view of the very large quantities of accumulated sludge in the refineries, the value of recovered oil is substantially high and thus profitable to the refineries. We have developed our Bio-mechanical Combination Process for this purpose. More details on this process can be furnished upon requst.