For the refining and petrochemical company Slovnaft (a member of MOL GROUP) with an annual processing of 5.5 – 6 million tons of oil, we designed, manufactured and supplied oil sludge pretreatment technology.
During oil processing, sludge containing oil, oil and solids is produced by flushing sewers and production capacities. These sludges are inherently no longer usable as raw materials. SLOVNAFT, a.s. therefore disposes of them in accordance with the Waste Act. Such disposal is currently quite expensive, because the price for disposal depends on the weight of the waste. The aforementioned waste contains variable amounts of water, soluble hydrocarbons, oils and insoluble substances. Under normal circumstances, SLOVNAFT can process these wastes in-house. However, processing at an internal WWTP is prevented by the inhomogeneous composition and the amount of insoluble solids.
In 2018-2019, we conducted a successful pilot sludge pretreatment trial. As a result, the refinery selected us as the supplier of sludge pretreatment technology called Internal Sludge Processing – ISP. The aim of this project was to design, engineer and also deliver, or rather, manufacture a technological unit. A device that allows sludge to be received, pretreated and pumped to an internal WWTP. There, it can then be disposed of in the refinery’s facilities.
The ISP technological device is capable of receiving inhomogeneous oil/oily sludge of various consistencies from tanker trucks as well as from a storage tank. Before entering the homogenization tank, the sludge is treated and mechanically removed from coarse impurities on vibrating screens. The treated sludge is chemically stabilized and diluted with water to the required concentration. As a result, pumpability and further processing in the refinery’s facilities are improved. The ISP device is also equipped with active air extraction and its filtration on a carbon filter. The process is controlled, automated and monitored by a PLC computer. The technological line for internal sludge processing was designed and delivered in the appropriate Atex class for explosive environments. The device has passed the certification process and has been successfully put into operation.
