SEARCH FOR METHODS TO INCREASE THE SEDIMENTATION RATE OF THE UPPER FLOATING LAYER OF OIL SLUDGE PITS

Abstract

Traditionally, oil sludge with a liquid-viscous consistency is separated into petroleum product, water and solid mechanical impurities. A large number of technological devices, including separators, centrifuges, hydrocyclones of various designs, have been developed to carry out the operation of interfacial separation of liquid-viscous oil sludge.On the territory of every oil refinery that has been in operation for decades, there are oil sludge ponds — natural settling ponds in which large quantities of oil waste accumulate.The problem of processing barn oil sludge in the oil production and refining industry has not yet been completely solved. This is due to the high stability of barn emulsions, the peculiarities of their composition and properties, which are constantly changing under the influence of temperature and various processes occurring in them.The article presents the results of research aimed at identifying the possibility of destruction of a persistent oil-water emulsion taken from the upper floating layer of an oil sludge pit and its preparation without changing the technological scheme and technological parameters.The results of laboratory studies on the destruction of oily liquid during static sedimentation are considered. Simulation of the oily liquid preparation process was carried out in compliance with the temperature and time conditions of operation, with the use of demulsifiers, by analogy with the process of oily liquid preparation, as at the unit. The results of the simulation showed that at the dosage of the demulsifiers used at the unit, even with an increase in the dosage and an increase in the settling time to 5 days, the oil-water emulsion did not collapse at 60 0C. Further studies were carried out by testing eight brands of demulsifiers at different dosages and elevated temperatures. Based on the results of the research and the conclusions made, a scheme for the preparation of oil-containing liquid at static sludge with the existing set of equipment at the unit is proposed.Further studies were carried out to increase the depth and sedimentation rate of the persistent oil-water emulsion.