Compositions of oil-based biodegradable drilling fluids and process for drilling oil and gas wells

摘要

Compositions of oil-based biodegradable drilling fluids are described, the compositions comprising an oil phase composed by methyl esters of soybean oil fatty acids, an aqueous phase finely dispersed in the oil phase by specific emulsifiers and several other additives having specific functions for providing suitable performance to the finished drilling fluid composition. The process to manufacture the inverted emulsion and the drilling process that employs the compositions of the invention are described too.