Removal of Water from Water-in-crude Oil Emulsions with Poly[(acrylic acid)-co-(sodium acrylate)] as Water-absorptive-polymers

• Published in: Journal of the Japan Petroleum Institute 2018/03/01, Vol.61(2), pp.59-71
• Main Authors: Nakano, Chiyu, Takada, Yuta, Chida, Yutaro, Kato, Sumio, Ogasawara, Masataka, Ikeuchi, Takao, Shindo, Takayoshi
• Format: Article
• Language: English
• Subjects: Absorption; Crude oil stockpiling; Demulsification; W/O emulsion; Water-absorptive-polymer
• ISSN: 1346-8804; 1349-273X
• DOI: 10.1627/jpi.61.59

Removal of water from water-in-crude oil (W/O) emulsions was investigated using poly[(acrylic acid)-co-(sodium acrylate)］as water-absorptive-polymer (WAP) at 15-70 °C and under 0.1-1.5 MPa employing a batch or a flow separation system. The W/O emulsions with water content of 1-5 mass% were prepared from Upper Zakum (UZ) crude oil reserved at a domestic oil stockpiling base and distilled water. In each separation system, water absorption rates of both granular and fibrous WAPs from W/O emulsions under ambient conditions were much faster than that of zeolite 4A, indicating an effectiveness of WAPs for water separation. Removal of water from W/O emulsions was enhanced at high temperatures (50-70 °C) and under high pressures (1.0-1.5 MPa). It was found that regeneration of used WAPs was possible by rinsing them in toluene followed by drying. These results indicate that absorption of water from W/O emulsion using WAP is considered as one of the promising physical demulsification methods such as centrifugal separation, thermal treatment, and gravitational sedimentation without using chemical demulsifier.