Drilling operators worldwide are increasingly facing environmental challenges while selecting high performance drilling fluids. In such a scenario water base drilling fluids are increasingly gaining popularity.
The drilling fluid technically known as mud is a mixture of clay, water, weighting agent (e.g. barite), polymer and other ingredients. This mud helps in dispersion of clay formations and dissolution of salt formation. In water base mud (WBM) system water is the largest component. It may be used in natural state or salt may be added to the system. Water based muds are of two types: Polyol mud and mixed metal-hydroxide mud (MMS).
Polyol mud is a generic term used for a wide class of chemicals based on glycerols, polyglycerols or glycols, such as propylene glycol, that are usually used in conjunction with an encapsulating polymer Partially Hydrolyzed Poly Acryl amide (PHPA) and brine phase KCL.
Polyglycol activated mud system, provide an effective and environmentally safe alternative to oil based drilling fluids to drill troublesome shales. This fluid delivers performance beyond that of conventional polymers and other water base fluids.
These polyglycols can be customised to meet a variety of drilling challenges- large diameter well bores, extended-rich drilling, deep water and sub salt applications and particularly reactive shales. It is also an idea system for drilling high-angle wells in reactive shale formation where wellbore stability, torque and drag are major concerns.