Silica Inhibition in Low Temperature Brine Disposal

Abstract

Silica inhibitor Geogard SX (GSX) was dosed to a mixture of silica-saturatedlo w temperatureb rine and well 5R13D discharge brine in the Malitbog secfor. GSX solution was injected at well 5R13D two-phase discharge spoo I before the brine is flashed in the twinsi/ encers targeting an effective dosing concentration in the brine mixture. The atmospheric-flashedb rine from well 5R13D /'s mixed with dumped brine from Malitbog main injection line to form a highly silicasaturated brine mixture collected at Pad 5R1 sump. This is subsequentlyp umped to Pad 502 along -2 km of alvenius pipelines frequently clogged by silica scales.

During the 23-days dosing period, a very thin layer of silica deposds were documented in silencer weirboxesa nd Pad 5R13b rine canal. However,G SX dosing did not totally eliminate silica deposition after 23 days as obserued during inspection of the brine flow path. Although, alvenius prpes utilized beyond the dosingp eriod revealed silica deposrfso f soft and easily removable type. Furthermore, throughout well 5R13D discharge period, no downtime was caused by severe silica deposition in the pumps and alvenius pipelines.