Alkalinity and pH-control additives are used to optimize pH and alkalinity in water-base drilling fluids. The control of many drilling fluid system properties is dependent on pH (e.g., the detection and treatment of contaminants such as cement and soluble carbonates). pH also affects the solubility of many thinners and divalent metal ions such as calcium and magnesium, and influences the dispersion or flocculation of clays. Ph control additives provides a suite of additives designed to control the degree of acidity or alkalinity in drilling fluids.
Controlling the pH of fluids is the function of an alkalinity control agent. Baroid IDP drilling fluid products require an alkaline pH in the range of 8.5 to 9.5 for optimum performance. Soda Ash, the product of choice to raise pH, removes calcium, softening the water and increasing the pH. This combination of treating out hardness and raising pH allows for maximum hydration of products.
The term “pH” denotes the negative logarithm of the hydrogen ion, H+, activity in aqueous solutions: pH = -log (H+) Field measurement of drilling fluid or filtrate pH and adjustments to the pH are fundamental to drilling fluid control. Clay interactions, solubility of various components and contaminants, and effectiveness of additives are all dependent on pH.