Silica Inhibitor Hot Injection Test at Bacman Geothermal Production Field, Botong, Philippines

Abstract

A series of pilot tests were conducted at the Bacman Geothermal Production Field, Philippines, in order to determine the effectiveness of the current silica inhibitor under hot injection conditions. A representative portion of the inhibitor-treated brine was diverted into a series of insulated one-half inch pipes, with retention vessels connected at the end. The test fluid’s velocity, retention time, and flow regime were set to mimic the brine’s characteristics during the actual hot injection scheme. Results of the latest test showed that at the current inhibitor concentration, dosing rate, brine chemistry, and Fluid Collection and Recycling System (FCRS) parameters, the predicted maximum deposition rate is 20 mm per year along the pipes, and an average of 54 mm per year inside the wellbore. The results indicate that a hot brine injection scheme is technically feasible.