Evaluation Studies of KCl and Amino Acid Mixtures for Clay Stabilization and Rheological Enhancement of Water-Based Fracturing Fluids

Abstract

Summary Conventional stabilizers such as inorganic salts in water-based fluids are restricted for use in gas and oil shales drilling and hydraulic fracturing for drilling due to environmental, economic and performance concerns. For example, 2% use of KCl, a commonly used inorganic salt, contains an excess of 9500ppm chloride. This is considered high and toxic. Apart from environmental problems, KCl inhibiting solutions tend to negatively affect the rheology of the water-based fluids, posing a dilemma for industry operators. The clay and rheological stabilizing effects of KCl and amino acid mixes for hydraulic fracturing operations were investigated in this study. The stabilizing and rheological potentials of mixes of KCl and organic compounds have proven to be superior to the separate compounds in studies. The KCl was used in the study at safe quantities (1%) to prevent toxicity concerns. In this study, the inhibition potentials of KCl+ Arginine and KCl + Alanine solutions, mixed approximately at ecologically safe quantities, were tested at different bentonite wafers using M4600 Linear swell at 25°C and 1000psi in the work. Furthermore, rheological studies on bentonite-based suspensions were carried out using a high-precision Discovery Hybrid Rheometer (DHR-1). This was done to monitor the flow parameters of the inhibiting suspensions and their anti-swelling effects on the bentonite component of the prepared fracturing fluid. The effects of the mixtures were also compared to that of KCl, Arginine and Alanine inhibition solutions. Herschel-Bulkley's model was also used to determine the flow characteristics. After 24 hours of testing, the swelling findings reveal that KCl+ Arginine/KCl + Alanine treated fracturing fluids significantly affect the clay stabilization and rheological properties of the fracturing fluid. The study provides basic information on the inhibition potentials of KCl and natural amino acid mixtures in water-based fracturing fluids for clean clay stabilization.