Analysis of the effect of polyanionic cellulose on viscosity and filtrate volume in drilling fluid.

The viscosity and filtrate volume of drilling fluid were tested by changing the polyanionic cellulose content in drilling fluid. The effect of polyanionic cellulose on the viscosity and filtrate volume of drilling fluid was analysed. The test results showed that the viscosity of drilling fluid increases with increasing polyanionic cellulose content. When the polyanionic cellulose content is below 1·5%, the viscosity increases slowly, whereas the viscosity increases rapidly when the polyanionic cellulose content is above 1·5%. Equation ( ) is a fitting equation that shows the relationship between viscosity and polyanionic cellulose content. The filtrate volume of drilling fluid decreases approximately linearly with increasing polyanionic cellulose content. Equation ( ) is a fitting equation that shows the relationship between filtrate volume and polyanionic cellulose content. Polyanionic cellulose can effectively improve the viscosity and reduce the filtrate volume of drilling fluid. [ABSTRACT FROM AUTHOR]