Geochemical study and fluid flow simulation of a groundwater system in Toyama and Joganji alluvial fans, central Japan, and assessment of suitability for heat utilization. (June 2021)

• Record Type: Journal Article
• Authors: Hirata, Hiromichi; Yoo, Seung-Youl; Iwatake, Kaname; Tebakari, Taichi; Okakita, Nagisa; Zhang, Jing; Ueda, Akira
• Is Part Of: Geothermics. Volume 93(2021)
• Publication Date: 2021-06
• Subjects: Geochemical -- Ground source heat pump system (GSHP) -- Groundwater -- Isotope -- Water flow; 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.2021.102073
• Languages: English
• ISSNs: 0375-6505

Abstract

Highlights: Chemical and isotopic compositions of groundwater in Joganji and Toyama alluvial fans were determined. The water quality and origins and water-flow mode with a 3-D state flow model was discussed. The groundwaters were mainly a mixture of the Joganji River water and precipitation and move from east to west. The groundwater was estimated at 4–10 m/day, and the residence time could reach 10 years. For the safety use of the GSHP, the saturation indices of scaling components such as CaCO3 were discussed. Abstract: For testing the potential and increased usage of a ground source heat pump system (GSHP), chemical and isotopic (D, 18 O) compositions of 50 shallow groundwater and six river water samples in Joganji and Toyama alluvial fans, central Japan, were analyzed to examine their water quality and origins with the simulation of the fluid flow mode using a 3-D state flow (transient) model. Results showed that groundwater was mainly a mixture of the Joganji River water and precipitation and moved from east to west. The groundwater flow velocity was estimated at 4–10 m/day, and the residence time could reach 10 years. The saturation indices of scaling components (deposit on heat exchanger) such as Fe and CaCO3 were discussed for the safe use of the GSHP.