Disposal of Flashed Brine Dosed with CaCO3 Scale Inhibitor: What Happens when the Inhibitor is Exhausted

Abstract

A freshly flashed geothermal liquid, previously dosed wlth inhibitor and supersaturated with calcite was injected into another well where It displaced an unflashed counterpart of itself around the wellbore. Back-production of the injectate, and subsequently the natlve fluid, has yielded data for the rate that a scale inhibitor is degraded after injection. The circumstance also dlsplays a novel mechanism whereby two fluids that do not physically mix nevertheless react wlth one another through the reservoir rock's serving a role of intermediary. The results have been further interpreted to conclude that in some circumstances a short lifetime for the scale inhibitor is not necessarily a problem for long-term lnjection.