Abstract: Today, the use of diesel in oil base mud is either prohibited or severely condemned due to its environmental impact. It also faces the obstacle of high disposal costs enforced by regulations set to lessen the environmental damage caused. This is forcing the industry to shift away from its use as it is becoming less feasible to operate with. A substitute base mud should be formulated in order to decrease the environmental impact, simultaneously abiding by regulations and in turn lower the overall costs. The focus on formulating a substitute-based mud using vegetable oils rather than diesel oil is gaining strong ground in the oil industry. Of these vegetable oils, Soybean oil shows great potential in both its characteristics and formulation cost. This paper is a stepping-stone into researching the feasibility of this oil. It discusses the approach that will be taken to assess Soybean oil base as oil base mud in order to conclude whether it is viable to be used as an OBM. The experimental work carried out showed high potential of Soybean base mud in comparison to oil base in both physiochemical and rheological properties as an oil and drilling fluid, better thermal stability in HPHT wells, safe due to its fire capacity resistance. The prepared Soybean base mud will perform the same function as diesel base mud, but more efficiently with less frictional pressure losses. Finally Soybean oil base mud is less expensive than oil base mud with less environmental impact and can be applied in the industry.

Keywords: soybean oil, oil-Base Mud, Diesel, drilling fluid, biodegradable oils, toxicity.