Due to the increasing volume of chemical reagents used in oil treatment, repair work and for intensification of oil production, anti-salt deposits, heavy oil deposites, asphaltene sediments, formation of emulsions, corrosion the technological processes of collecting and preparing oil become more complicated, which leads to the formation of intermediate layers and a failure of the technological regime of oil preparation. It leads to the formation of intermediate layers and failure of the technological mode of oil treatment. The research is aimed at studying the effect of the products of hydrochloric acid well treatment reactions on the kinetics of oil-water emulsion destruction, on the performance of oil desalting process, on the quality of water treatment. The research results have shown that products of reactions of hydrochloric acid treatment of wells and decrease in pH value of the aqueous phase influences kinetics of oil-water emulsion destruction at oil treatment plants. The stability of oil-water emulsion increases with decreasing the pH value of water. The amount of oil-water emulsion formed with water with low pH value, which affects the quality of oil treatment, has been determined. The possibility of breaking the stable water-oil emulsion formed by water with low pH value when increasing from pH=3.1 to pH=6.5 by NaOH solution has been evaluated. Laboratory researches have been carried out to determine influence on water treatment quality and time needed for water treatment to the quality required by design documents taking into account products of hydrochloric acid well treatment reactions received at oil treatment unit. It was also found that treatment of oil with hydrochloric acid does not affect the quality of water treatment. Measures to minimize the risks of failure of the technological mode at the oil treatment plants due to the formation of persistent oil-water emulsions are proposed.
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