Laboratory Study of the Effect of Modified Starch Polymer on the Flow Properties of Drilling Mud

Today, a major part of the cost of drilling oil and gas wells to reach hydrocarbon resources belongs to drilling fluids, and every year large sums of money are spent to buy the raw materials needed to make suitable drilling fluids for drilling formations with special problems. Therefore, the accurate knowledge of the formations and also the selection of the best drilling fluid with the highest efficiency for the purpose of drilling wells, in terms of reducing costs and in the stability of the well wall, as well as improving other factors for the optimization of drilling operations, are very important.In this article, in order to optimize the design of water-based drilling fluid with appropriate rheology, first, an initial water-based drilling mud will be made as the base fluid. Then, in order to check the effect of the appropriate modified starch polymer on it, first this ordinary starch polymer material is added to the base drilling mud and the main parameters and indicators of the drilling fluid, including the weight of mud strainer, thickness of mud cake, viscosity and acidity level of mud are measured. Then the same operation is repeated with modified starch polymer and the best aqueous base fluid made using these additives is selected for use in oil and gas wells.The results of the experiments show that the efficiency of ordinary starch polymer is only at ambient temperature because it is fermented at high temperatures and loses its efficiency. Meanwhile, the modified starch with its special composition shows high resistance to fermentation at high temperatures and has the ability to control drilling mud filtrates in a very large amount.

کلیدواژه ها:

Polymer ، Modified starch ، Drilling mud rheology