PYROLYSIS OF THE HYDROCARBON PART OF OIL SLUDGE FORMED AS A RESULT OF OIL REFINING

Abstract

The article proposes a method for obtaining motor fuel components by low-temperature pyrolysis of the hydrocarbon part of long-term storage oil sludge. The advantage of this method is the possibility of processing raw materials of any composition. For the research, oil sludges formed during oil processing at PJSC "Neftokhimik Prykarpattya" (Nadvirna, Ivano-Frankivsk region) were used. Sampling was carried out from a long-term storage pond at different depths. Then, using heat treatment methods with the addition of water, settling, filtering and drying, the organic (hydrocarbon) part was separated from the oil sludges. Based on the results of derivatographic analysis, it was established that the optimal temperature range for thermal destruction of the hydrocarbon part of oil sludges is 420-460°C. The pyrolysis process was carried out on a laboratory batch plant at a temperature of 440 °C, in a metal sealed reactor with a water cooler and a receiving flask. As a result of pyrolysis, liquid pyrocondensate, solid residue in the reactor and pyrolysis gases were obtained. The pyrocondensate was separated into narrow fractions – gasoline, diesel and residue – and their properties were studied to determine the directions of practical application. The gasoline fraction contains a high content of sulfur and unsaturated hydrocarbons, so it can be used as a component of commercial gasoline after hydrotreating and catalytic reforming. Similarly, the diesel fraction, after hydrotreating, is suitable for the production of commercial diesel fuel. The residue after distillation of pyrocondensate can serve as a component of fuel oil or an additive to plastic lubricants. The solid residue formed during pyrolysis is recommended for use in road construction for the arrangement of the lower layers of the road surface. Using X-ray fluorescence spectral analysis, it was established that the content of metals in the pyrocondensate, its fractions and the residue is quite low, which contributes to their further processing by catalytic processes. In the fractions of the studied pyrocondensate, an increase in the concentration of metals is observed with an increase in the boiling point of the fractions.