Effect of Additives on Rheological Properties and Fluid Loss of Oil Based Drilling Fluids





Oil-based drilling fluids are often used to drill geothermal or petroleum wells in hot  locations. These fluids normally consist of dispersion of organophilic clays in water-in-oil  emulsions. If loss of fluid to the formation is expected, fibres or other additives for fluid loss  prevention are added.

In the present article results from a study showing the effects of the additions of weight  materials and asphaltic resin-based fluid loss prevention additive on rheological properties of  the drilling fluids are shown. These results show the complex behaviour of the mixture of these  particulate materials into emulsions. Filtration control is measured in a pressure cell where the flow goes through filter paper with 11 and 22 microns opening.

Author Biographies

Blandine Feneuil

Research Scientist

Jan David Ytrehus

Senior Research Scientist

Arild Saasen

Faculty of Science and Technology
Department of Energy and Petroleum Engineering
University of Stavanger


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