Mechanistic Study of Scale Inhibitors' Retention in Carbonate Reservoirs
One of the most effective measures for avoiding the formation of mineral scale is to prevent its deposition by the use of chemical scale inhibitors (SI). These inhibitors are usually applied in the near-well formation by means of a "squeeze" treatment. Once these SI chemicals are placed into the formation, they may interact with the formation minerals through some processes, such as adsorption or precipitation.
It is these interactions that affect the SI retention within the reservoir and the subsequent release of SI in the squeeze treatment. As about 50% of the world's oil production takes place from carbonate formations, especially in the Middle East, understanding the chemistry behind the mode of retention of the inhibitors within carbonate formations is an important issue.
Our experimental results show that different adsorption/precipitation (/) regimes are clearly demonstrated in carbonate mineral substrates for the scale inhibitors, the rather different behaviour of Scale Inhibitors may be ascribed to different functional groups having different strengths of SI – Ca binding.
Professor Ken Sorbie, Mike Singleton and Dr. Lorraine Boak