Geochemistry Monitoring in Kamojang Vapor-dominated Geothermal Field from 2010 to 2013

Abstract

During more than 30 years production steam and energy for Indonesia, monitoring activity of Kamojang geothermal field have successfully been done by both reservoir and geochemistry department to maintain steam production sustainably. The last three years (2010-2013) geochemistry monitoring have been done by monitoring pressure, temperature, production and chemistry of non-condensable gas (NCG) also condensate liquid for each production wells. Moreover the condensate injection rate and tracer injection at KMJ-21 injection well also monitored to obtain comprehensively study. NCG trend for 2010 and 2013 are unlikely to change, high in the southern area, southeast, and the east-southeast. In well KMJ-75 the NCG decline which could be an indication of the condensate injection breakthrough because condensate injection rate was increased. The tracer injection study also shown that condensate injected has connection with well which is near and locate at same cluster with KMJ-75. Temperature, pressure and wells production Trend for 2010 and 2013 are also unlikely to change, high in the southeast area. The wells on west-southwest area have the highest superheat value due to the exploitation process is longer than the wells on east-southeast area. Lack of injection of condensate on that area might cause decrease in pressure and an increase superheat in the wells