Holych Y. Formulation of New Nonionic Demulsifiers For Dehydration of Complex Crude Oil Emulsions

Ph.D. thesis in Engineering Sciences Majoring in 05.17.07 – Fuels and Lubricants Chemical Engineering. – National Aviation University, Kyiv, 2019. The paper is dedicated to solving a problem of dehydration of complex crude oil emulsions. There have been determined main characteristics of crude oils subject to dehydration and solutions of block co-polymers used as demulsifiers. Effect of emulsion settling duration and amount of added demulsifier on efficiency of emulsion dehydration has been explored. Demulsifiers were tested on artificial crude oil emulsions prepared using crude oils from East-Ukrainian, Orkhovychy, Kokhanivka oilfields and aqueous solution of NaCl that differed in quantitive content and method of preparation. Demulsifier with molecular weight of 3500 and ethylene oxide / propylene oxide ratio of 85/15 has been selected for further research. Technical specification has been developed for this demulsifier as a product with commercial name «DM-3 Demulsifier». There have been determined optimal process parameters of dehydration of artificial emulsions composed of a mixture of crude oils and slop oil. Analysis of the research results showed that an optimal content of slop oil in an emulsion, at which the dehydration process takes place, does not exceed 10 %. To improve detergent properties, polyethylene glycol (PEG) with molecular weight of 400 was added to the demulsifier. It has been found that addition of PEG improves demulsifying capability of the demulsifier by 14–16 % under dehydration temperatures of 60–70 ºС and by 3 % under temperature of 80 ºС. The paper presents DM-3 demulsifier formulation and production process diagram. It has been found that demulsifiers being tested inhibit corrosion processes and demonstrate protective effect. DM-3 has demonstrated the highest protective performance at 42,8 %. Efficiency of DM-3 demulsifier was studied in commercial application. Laboratory and industrial tests have proven high performance of devised DM-3 demulsifier in comparison with known PМ-1441, Dissolvan 4411 and Demtrol. Key words: demulsifiers, crude oil, emulsions, properties, recipes, technology, dehydration.