Analysis of organic tracer tests from reinjection well K-26 and IDDP-1 at the Krafla geothermal field in Iceland

Abstract

Two organic tracer tests were conducted in the Krafla geothermal field in the summer of 2009, conducted by BRGM in collaboration with ÍSOR and Landsvirkjun. The test was performed within the European HITI project, which lent support to the IDDP. The IDDP research program was prepared to evaluate improvements in the efficiency and economics of geothermal energy systems containing supercritical fluids. The goal is to generate electricity from natural supercritical hydrous fluids at least 374°C hot and deep (4- 5km) geothermal reservoirs. This thesis describes the main geological and technical issues that need to be considered when conducting a tracer test. The place where the tracer test was conducted was Krafla high- temperature field located in northern Iceland. The main objectives of the project was to examine if well IDDP- 1 and K- 26 have any hydraulic connection with other wells in the field that are connected to the existing geothermal power plant. Careful planning is required for successful reinjection, in particular when considering reinjection near the magmatic IDDP-1 well. The tracer test was conduct using both an existing reinjection well K- 26 and also the IDDP-1 well to detect the connections between reinjection and existing production wells and also to predict subsequent cooling effect of the reinjection. This thesis provides a description of the principles of sustainable research using mathematical modeling of one dimensional flow provided by ICEBOX software and geophysical literature. The results will be used to simplify the problem of analyzing the experienced low recovery of the organic tracer tests used as input into the model. Polish conditions were based on the actual situation in country and improvement of the tracer test in the low temperature geothermal field as is common in this area.