Recent Innovations in Pigging Technology for the Removal of Hard Scale from Geothermal Pipelines

Abstract

Scaling of production lines and especially injection piplines and pipelines to brine ponak is common in many geothermal power operations. Previous w r h 9 Stock (1990) and Brown (1995) have discussed methoak to monitor and calculate scale build-up in injection lines by pressure drops and Klein (1995) recently discussed methoak for predicting and suppressing sccling in reinjection lines and wells. i'liese writers have mentioned the process ofpigging to remove scale deposits, but the geothermal literature is virtually devoid of injormation related to the use of pigging operations to remove geothermal scale in pipelines. In developing nav and innovative tooling to tackle the extreme pipeline scaling problems of the Salton Sea geothermal plants, E-P & Associates has gained a wide range of experience in removing very hard scale. By implementing a program of regular monitoring of injection lines as proposed by Stock, Brown and Klein and the scheduling of regular cleaning events using improved pigging techniques; pigging operations 110 longer need to be viewed as a dreaded event, but just routine maintenance.