Application of Electrical Capacitance Measurements to Study the Collapse of Oil Foams

Daniel Pacho1 and Graham Davies2

1 Facultad de Ingeniería Química, Universidad Autónoma de Yucatán

Av. Juárez 421 Cd Industrial Mérida 97288 Mexico. email: jpacho@tunku.uady.mx

2 Department of Chemical Engineering, UMIST

PO Box 88 Manchester M60 1QD United Kingdom. email: graham.davies@umist.ac.uk

ABSTRACT

The formation of stable oil-gas foams is a significant industrial problem in the production of oil and gas. During primary separation of petroleum, severe foaming could produce serious operational restrictions. Among the current methods used to handle oil foams are knitted wire pads, perforated plates or chemicals. But when stable foams are formed they are conventionally broken by the addition of antifoaming agents. However the functioning of these agents is ill understood and they are often not optimally applied.

Electrical Capacitance techniques have been applied to study the stability and collapse of oil foams as a way to understand foam drainage. The versatility and the non-intrusive nature of Electrical Capacitance techniques make them an attractive tool to carry out a detailed study of foam dynamics aiming to devise an improved strategy of use of antifoaming-agents.

With the use of Electrical Capacitance it was possible to identify the air-foam and foam-liquid interfaces within a range of few millimeters. It was also demonstrated that accurate monitoring of the foam density (liquid content in the foam) was possible, thus allowing the generation of full foam drainage profiles. Data form Electrical Capacitance measurements can be processed to obtain information on liquid distribution in the foam as a function of foam height and time. Additionally the analysis of results showed that it is possible to recognize the main collapse processes taking place during foam collapse as well as the time and section of the foam in which they are occurring.

The application of Electrical Capacitance to study oil foam collapse has yielded promising results that encourage its further exploitation in the development of a novel methodology of foam control.

Keywords Oil Foams, Electrical Capacitance, Drainage, Collapse