The basic process of preparing fresh water using aluminum hydrochloride is considered. The negative effect of a coagulating reagent on dehydration and desalination during primary oil preparation is shown. It has been laboratory-confirmed that an increased content of suspended particles in suppressed fresh water for desalination naturally worsens the residual water content in oil. It was noted that the presence of the coagulant “hydroxyl chloride aluminum” increases the residual water content in the oil, however, the content of chloride salts decreases. It is assumed that the determination of chloride salts using the titrimetric method according to GOST 21534-76 (method A) is affected by the presence of aluminum ions. The formation of “heavy” aluminum-asphaltene complexes from the point of view of chemical structural interactions is raised. The aluminum ions included in the composition of asphaltene compounds are able to “capture” water molecules and concentrate on the oil-water interface, subsequently forming intermediate layers in technological devices and thereby impair the preparation of oil. During laboratory and field tests, it was found that in the spring flood period, in order to achieve standard indicators for the residual content of water and chloride salts in oil, it is necessary to change the water treatment technology. The use of fresh water after its additional static sludge in reinforced concrete tanks for 8 hours (an increase in sludge time due to available production facilities), as well as strict adherence to the coagulant dosage in the range of 50-60 ppm allow us to achieve standard oil performance in 1 quality group according to GOST R 51858-2002.
References
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2. Muravlenko S.V., Artem'ev V.N., Khisamutdinov N.I. et al., Razrabotka neftyanykh mestorozhdeniy (Oil field development), Part 3, edited by Khisamutdinov N.I., Ibragimov G.Z., Moscow: Publ. of VNIIOENG, 1994, 49 p.
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