Print Email Facebook Twitter Development of thermal fractures in two Dutch geothermal doublets Title Development of thermal fractures in two Dutch geothermal doublets Author Loeve, D. Veldkamp, J.G. Peters, E. van Wees, J.D.A.M. Publication year 2015 Abstract In the production well of a low-enthalpy geothermal doublet hot water is pumped from reservoirs at about 50-1007deg;C. After passing through a heat exchanger, the cold water is re-injected at about 20-357deg;C in the injection well into the reservoir, which initially has the same temperature as the produced water. Under some circumstances, this may lead to the initiation of thermal fractures around the injection well, an effect known from water injection in oil wells. This will increase the productivity index (PI), thereby also increasing the efficiency and profitability of the doublet. Using a simple analytical approach, we studied whether thermal fractures are theoretically expected under typical reservoir and injection conditions. From data at high temporal resolution of two geothermal doublets were studied over a longer period of injection to check if the development of a thermal fracture is observed The conclusion that can be drawn from the calculations is that cold fractures hardly develop under the assumed conditions. However, the uncertainty on the pressure estimation necessary for the fracture calculation is relatively large. Possible fracture development is very sensitive to value of the minimum horizontal stress and lowering by 10% allows the initiation of fractures in both doublets. Subject GeoPG - Petroleum Geosciences SGE - Sustainable Geo EnergyELSS - Earth, Life and Social SciencesGeological Survey NetherlandsGeosciences2015 EnergyEarth sciencesFractureOil well floodingWater injectionWellsAnalytical approachProductivity index To reference this document use: http://resolver.tudelft.nl/uuid:7bbe9261-b7df-4b1a-8c80-7f973dc08c77 TNO identifier 533272 Publisher SEuropean Association of Geoscientists and Engineers, EAGE ISBN 9781628418620 ISSN 0277-786X Source 3rd Sustainable Earth Sciences Conference and Exhibition: Use of the Sub-Surface to Serve the Energy Transition, 13 October 2015 through 15 October 2015, 116-120 Article number 96520D Document type conference paper Files To receive the publication files, please send an e-mail request to TNO Library.