Field demonstration of the combined use of thermally-degrading and cation-exchanging tracers to predict thermal drawdown in a geothermal reservoir. (January 2020)

• Record Type: Journal Article
• Authors: Reimus, Paul; Caporuscio, Florie; Marina, Oana; Janney, David
• Is Part Of: Geothermics. Volume 83(2020)
• Publication Date: 2020-01
• Subjects: Tracers -- Reactive tracers -- Thermal drawdown -- Hydrolysis -- Cation exchange; Hydrogeology -- Periodicals; Geothermal resources -- Periodicals; Énergie géothermique -- Périodiques; GEOTHERMAL ENGINEERING; GEOTHERMAL ENERGY; GEOTHERMAL EXPLORATION; Geothermal resources; Hydrogeology; Periodicals; Electronic journals; 621.44
• DOI: 10.1016/j.geothermics.2019.101712
• Languages: English
• ISSNs: 0375-6505

Abstract

Highlights: Nonreactive, thermally-degrading, and cation-exchanging tracers were deployed. The thermally-degrading tracer placed constraints on magnitude of thermal drawdown. The cation-exchanging tracer placed constraints on timing of thermal drawdown. Uncertainties associated with the thermal drawdown predictions are discussed. Repeated use of thermally-degrading tracers could reduce predictive uncertainty. Abstract: A tracer test was conducted in a geothermal reservoir using a cation-exchanging tracer to interrogate flow pathway surface area to volume ratios and a thermally-degrading tracer to interrogate average flow pathway temperatures. The test interpretations are used to predict when thermal drawdown will occur at a production well due to injecting cooler spent geothermal water into an injection well. The cation-exchanging tracer provides constraints on the timing of thermal drawdown, and the thermally-degrading tracer provides constraints on the magnitude of thermal drawdown. Uncertainties associated with the method, including assumptions made about flow pathway geometry, are discussed.