DBPapers
DOI: 10.5593/sgem2017/12/S02.078

NUMERICAL MODELING OF BRACKISH WATER INJECTION TO LOW-MINERALIZED GEOTHERMAL AQUIFER

M. Miecznik, B. Tomaszewska
Sunday 10 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7105-99-5 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 12, 611-618 pp, DOI: 10.5593/sgem2017/12/S02.078

ABSTRACT

Productivity of geothermal reservoirs is often limited by capability of injection wells due to clogging of near-filter zone or increased viscosity of cooled waters. Especially for highly saline reservoirs, injection of cooled waters to water-bearing formation is often the only way of their disposal. In turn, this phenomena has little importance in case of low-mineralized waters. However, several water-treatment procedures can be used to recover valuable minerals, thus producing diluted water and salt concentrate. Diluted water in case of meeting sanitary conditions can be directed to water municipal systems, while salt concentrate can be mixed with the remaining water being injected to the reservoir. Operation of geothermal aquifer in this manner increases the amount of injected water, consequently increases their salinity. To estimate potential risk of salt precipitation and decrease in reservoir permeability a numerical modeling of geothermal reservoir was performed. TOUGH2 numerical simulator was used to investigate variability of flow rate and salinity of injected waters on pressure rise and permeability drop in the Podhale geothermal system (South Poland).

Keywords: brackish water injection, numerical modeling, Podhale geothermal system, geothermal reservoir, TOUGH2