Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield
The Second Oil Production Plant of Xinjiang Oilfield produces a large amount of highly emulsified crude oil, which has a serious impact on the subsequent oil–water separation. At present, the concentration of demulsifier has increased to 2000 mg/L, but the demulsification effect is still poor. In th...
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MDPI AG
2023-03-01
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author | Jingui Ma Liqiang Ma Yongdi Gao Yue Qin Zhihao Jiao Ruibo Guo Junwei Hou |
author_facet | Jingui Ma Liqiang Ma Yongdi Gao Yue Qin Zhihao Jiao Ruibo Guo Junwei Hou |
author_sort | Jingui Ma |
collection | DOAJ |
description | The Second Oil Production Plant of Xinjiang Oilfield produces a large amount of highly emulsified crude oil, which has a serious impact on the subsequent oil–water separation. At present, the concentration of demulsifier has increased to 2000 mg/L, but the demulsification effect is still poor. In this paper, the source and physical properties of highly emulsified crude oil are investigated firstly. The results show that highly emulsified crude oil is composed of three kinds of liquid: (1) conventional water flooding (WF); (2) chemical flooding (CF); (3) fracturing backflow fluid (FB). Among them, high zeta potential, low density difference, high viscosity, and small emulsion particles are responsible for the difficulty in the demulsification of the WF emulsion, while the high pH value is the reason why the CF emulsion is difficult to demulsify. Therefore, systematic experiments were implemented to investigate the optimal demulsification approach towards the three liquids above. As for the WF emulsion, it was necessary to raise the temperature to 70 °C and the concentration of the demulsifier to 200 mg/L. Moreover, it was only necessary to add 200 mg/L of demulsifier to break the CF emulsion after adjusting the pH value to 7, while no extra treatments were needed to break the FB emulsion. We hope this study can provide a new insight for the treatment of emulsions in the later stage of oilfield development. |
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issn | 1420-3049 |
language | English |
last_indexed | 2024-03-11T06:05:48Z |
publishDate | 2023-03-01 |
publisher | MDPI AG |
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series | Molecules |
spelling | doaj.art-0aaa45ca32d0443684ae1be65adfcc412023-11-17T12:56:22ZengMDPI AGMolecules1420-30492023-03-01286287310.3390/molecules28062873Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang OilfieldJingui Ma0Liqiang Ma1Yongdi Gao2Yue Qin3Zhihao Jiao4Ruibo Guo5Junwei Hou6State Key Laboratory of Heavy Oil Processing, School of Engineering, China University of Petroleum-Beijing at Karamay, Karamay 834000, ChinaShanghai EHS Value Environment Technology Co., Ltd., Shanghai 202150, ChinaZhoushan High Tech Industrial Zone Development and Construction (Group) Co., Ltd., Zhoushan 316000, ChinaCNCP Auditing Service Center Company Limited, Beijing 100028, ChinaPetroChina Kalamay Petrochemical Company, Karamay 834000, ChinaPetroChina Kalamay Petrochemical Company, Karamay 834000, ChinaState Key Laboratory of Heavy Oil Processing, School of Engineering, China University of Petroleum-Beijing at Karamay, Karamay 834000, ChinaThe Second Oil Production Plant of Xinjiang Oilfield produces a large amount of highly emulsified crude oil, which has a serious impact on the subsequent oil–water separation. At present, the concentration of demulsifier has increased to 2000 mg/L, but the demulsification effect is still poor. In this paper, the source and physical properties of highly emulsified crude oil are investigated firstly. The results show that highly emulsified crude oil is composed of three kinds of liquid: (1) conventional water flooding (WF); (2) chemical flooding (CF); (3) fracturing backflow fluid (FB). Among them, high zeta potential, low density difference, high viscosity, and small emulsion particles are responsible for the difficulty in the demulsification of the WF emulsion, while the high pH value is the reason why the CF emulsion is difficult to demulsify. Therefore, systematic experiments were implemented to investigate the optimal demulsification approach towards the three liquids above. As for the WF emulsion, it was necessary to raise the temperature to 70 °C and the concentration of the demulsifier to 200 mg/L. Moreover, it was only necessary to add 200 mg/L of demulsifier to break the CF emulsion after adjusting the pH value to 7, while no extra treatments were needed to break the FB emulsion. We hope this study can provide a new insight for the treatment of emulsions in the later stage of oilfield development.https://www.mdpi.com/1420-3049/28/6/2873water floodingchemical floodingfracturing backflow fluidprocess optimizationdemulsification |
spellingShingle | Jingui Ma Liqiang Ma Yongdi Gao Yue Qin Zhihao Jiao Ruibo Guo Junwei Hou Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield Molecules water flooding chemical flooding fracturing backflow fluid process optimization demulsification |
title | Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield |
title_full | Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield |
title_fullStr | Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield |
title_full_unstemmed | Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield |
title_short | Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield |
title_sort | study on wastewater demulsification technology of crude oil in xinjiang oilfield |
topic | water flooding chemical flooding fracturing backflow fluid process optimization demulsification |
url | https://www.mdpi.com/1420-3049/28/6/2873 |
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