Clearly, drilling operations involve the optimization of mechanical and chemical processes to not only make the hole but to keep and deliver it. Such is the dynamism of the drilling fluids as it is one ‘tool’ that fulfills these two processes simultaneously, especially in its interaction with the wellbore and other mostly mechanical tools.
The design of drilling fluids basically considers the harmonization of different chemicals to ensure adequate formation control and compatibility with various mechanical parts, especially elastomeric parts of mud pumps, measurement, and directional tools, etc. A drilling fluid system is designed to specific specifications (technical) based on drilling objectives. For instance, not primarily considering the quantity of lime and emulsifiers to be used, we will require an electrical stability reading above 400v for a typical synthetic base system. These specifications, however, are a function of aggregation and harmonization of different quantities (commercial). Evidently, the most cost-effective option is the chemical additives that have the highest purity level. Overall, the least possible concentration presents the most desirable results. Adulteration is the only means of cheapening a chemical product, and this involves the reduced concentration of the active chemical ingredients in the chemical additives, and in a bid to fulfill the market branding volume and size, this is achieved by the addition of inactive chemicals and these end up making up huge volumes of impurities. For instance, quicklime (CaOH2) is blended with cheaper CaCO3 and comes cheaper. Wherever such is used, more sacks of such low-grade products are required to achieve the desired properties- proper emulsification, else this property would not be achieved, and drilling ops compromised.
This leads straight into another cost- incurring angle because of cheaper but adulterated chemicals- the side effects of impurities. This is akin to the side effect of taking cheaper medicine brands. These impurities themselves are either reactive or inert chemical compounds and materials. At the least, however, they end up impacting the rheological properties of the fluid system, and even this has to be treated out by base fluid dilution (increased treatment cost) or the employ of solids control equipment (increased equipment cost). Like cheap medicine, the employ of more inexpensive chemicals owing to cheap contractual agreement guarantees increased primary treatment cost and the secondary treatment of side effects of impurities if death (as in medicine) or loss of well or tool, will be avoided.