Polymer Drilling Fluids in the 1990's: Will They Replace Oil-Based Muds?

The 1990's have seen a surge in new water-soluble polymers available to the drilling industry. Many new polymers offer enhancements or significant improvements. It has often been said that this polymer system is just as good as oil mud,'' or this product will replace oil mud.'' These claims have negatively affected acceptance of new polymers, retarding their field applications regardless of technical and/or economic merit. A general understanding of polymer classification and knowledge of the strengths, weaknesses, molecular weight, and functionality can facilitate selection and treatment strategy for polymers. No one polymer chemistry or system will replace all the performance characteristics of oil-based fluids; however, some polymers are being used successfully in some oil-mud applications. This paper compares these various characteristics.