Rheological studies and optimization of Herschel–Bulkley parameters of an environmentally friendly drilling fluid using genetic algorithm

Rheological Properties of Bentonite/Polymer Based Drilling Fluid Under Different pH Conditions

“…The molecular weight of the used PEG is about 6000 g/mol. This polymer prevents foam and syneresis in the bentonite/HEC system [19]. The pH of the base fluid is changed by adding droplets of HCl or NaOH of 0.1 N to the suspension water/bentonite/polymer.…”

“…Using bentonite alone cannot satisfy the rheological and filtration properties of drilling fluids. It represents several drawbacks such as, reducing productivity of the drilling operations, provoking formation damage, and leading to differential pipe sticking [19]. Therefore, the introduction of other additives to formulate drilling fluids is of paramount importance to improve the effectiveness of this fluid.…”

“…Different additives can be used and among them, the water-soluble polymers can be found. It is also found that degradable, nontoxic and environmentally friendly water-soluble polymers are the most performant additives [19]. Hydroxyethyl cellulose (HEC) and polyethylene glycol (PEG) are one of the functional additives that can be lead to an appropriate formulation of drilling fluid.…”

“…This work is devoted to illustrate the changes in bentonite-polymer based mud rheology when changing its pH. The studied drilling fluid is an environmentally friendly one, formulated based on two different Algerian bentonites and two water-soluble polymers as stated in Ouaer et al [19]. The obtained results will help drilling engineers to understand the modifications of drilling fluid rheological properties induced by changing the pH.…”

Study on Attapulgite as Drilling Fluid Clay Additive in Persian Gulf Seawater

“…Also it is evident that an increase in clay (bentonite and attapulgite) concentration results in higher k, yield stress and gel strength values. This is due to the fact that at higher clay concentration a stronger three dimensional network and gel structure is formed between clay particles and water molecules [31]. However, despite of consistency index, yield stress and gel strength, an increase in clay concentration resulted in a slight decrease in n value.…”