Sustainable and Green Drilling Fluid Additives Development

Abstract

Oil and gas drilling requires several components work simultaneously to ensure smooth and safe drilling. Drilling fluid or mud is an inseparable part of drilling oil and gas wells and circulated through out theh drilling operation. Drilling fluid contains a variety of additives or chemicals to provide various properties to drilling fluid namely viscosity, fluid loss control, emulsion stability, lubricity, etc. Developing environment friendly chemicals to provide the above-mentioned drilling fluid properties is a significant step taken towards sustainability and reducing carbon footprint besides suitability for aquifers and offshore environments. Several fatty acid-based chemicals used in drilling fluids as fatty acids offer eco-friendly and bio-degradable properties besides required drilling fluid properties. Vegatable oil contains triglycerides which is a potential source of fatty acids and their derivatives. Waste vegetable oil (WVO) provides a perpetual and sustainable source of raw material for various types of eco-friendly additives development. Waste vegetable oil is subjected to simple chemical modification of base hydrolysis process and mixtures of fatty acids have been obtained after finishing a sequence of clean-up process of reaction mixture. The fatty acids obtained are environment-friendly, bio-degradable and non-toxic. Due to technical, economic and environmental advantages of products derived from waste vegetable oils, we have undertaken several research projects to produce various chemicals from waste vegetable oil for oil and gas field applications. Fatty acid-based products mainly used in drilling fluids as lubricants to reduce torque and drag for water-based mud. In case of oil-based mud systems, fatty acid derived products are used as emulsifiers, wetting agents and rheology modifiers. However, these products have been either mixture of fatty acids and their derivatives or only derivatives of fatty acids. In our study, we have used the mixture of fatty acids obtained from chemical conversion of WVO for applications as lubricant for water-based mud and emulsifier and rheology modifier for invert emulsion oil-based mud systems. In this paper, we described the chemicals process for converting waste vegetable oil to fatty acids by base hydrolysis reaction in the first section. Application of synthesized fatty acids for water-based and oil-based mud formulation as lubricants, emulsifiers and rheology modifiers have been discussed in the second part of the paper.