The Application of Organic Shale Inhibitor as A High Performance Water Base Mud (HPWBM) to limit hydration of shale/clays: A Laboratory Study

Abstract

Adding additives such as inorganic shale inhibitor (NaCl, CaCl2, KCl and NaSiO3) and polyamine (MAL-SHALE HIB/MSH) reduce hydration in clay. Inorganic shale inhibitor only effective as long as water-based drilling fluids that contain these salts are in contact with the clays (temporary inhibition), the salt- containing fluid is displaced by fresh water, the clay will swell because  hydration, and destabilizing the drilled formation. Inorganic shale is effective in shale formation where smectite is predominant clay mineral. Inorganic shale inhibitor is ineffective when clay contain a few cation or no exchangeable cation. A large quantity of salts such as brine (high salinity) or other electrolytes have been used to increase the ionic concentration of the water phase in order to retard osmotic hydration. Inorganic shale inhibitor adversely affect the chemical biological ecosystems above limits. This paper study about polyamine shale inhibitor/MSH to limit hydration shale/clay and to mitigate environment issue with salts.  Polyamine/MSH is organic shale inhibitor that is permanent shale inhibitor because due high cationic exchange capacity and smaller hydrated ion radius compare to inorganic shale inhibitor. Single cation exchange mechanism that is shale matrix/surface reacting. Cationic source is cationic amine compounds. MSH is a persistent proprietary of mixture polyamine. Shale inhibitor material that is effective in preventing swelling of shale/clays. MSH properties are appearance clear yellowish to amber liquid, specific gravity around 1.12-1.17, pH: 7-9, and soluble in water that acts as a clay hydration suppressant, by intercalating and reducing the space between the clay platelets so that water molecules will not penetrate and cause shale swelling.