Heterogeneity determination of the Delft subsurface for heat flow modelling

Heterogeneity determination of the Delft subsurface for heat flow modelling

Gilding, D.T.

Bruining, J. (mentor)
Donselaar, M.E. (mentor)
Wolf, K.H.A.A. (mentor)

Civil Engineering and Geosciences

Geotechnology

Petroleum Engineering

2010-06-18

Geothermal energy is hot and sustainable. A recent run for licences has sparked questions on the optimisation and recovery of geothermal energy from the subsurface of the Netherlands through optimal project placement. The effect of heterogeneities on interference of geothermal projects in the West Netherlands Basin and the target Early Cretaceous Delft Sandstone Member has not been sufficiently studied. The objectives of this study are: (1) to gain a better understanding of the geological setting, the depositional setting and the heterogeneities of the primary target Delft Sandstone Member; (2) to show the effect of heterogeneities in the subsurface on interaction and interference of flow on closely placed geothermal systems; and (3) to build a subsurface dynamic reservoir model with which optimal well performance and placement can be assessed. The basin evolution, depositional setting and depositional processes of the Delft Sandstone Member are determined by combining the available data. The seismic, well, core and cutting data are combined to build a static 3D reservoir architectural model of the Delft subsurface. The static model is incorporated with the flow characteristics from petrophysical log data and used for temperature and fluid flow behaviour simulations. By modelling flow and temperature behaviour, the flow rates and production temperatures of a single geothermal system and the interference of the different geothermal systems were determined and quantified. This study gives new insights and a better understanding of the reservoir architecture of the Delft Sandstone Member. The Vrijenban Syncline is the predominant structure in the Delft subsurface and the sediments of the Delft Sandstone Member are deposited by a meandering fluvial system in three different depositional settings, controlled by tectonic movement. The depositional characteristics related to subsidence and accommodation space increase can have a large impact on the reservoir behaviour of the Delft Sandstone Member. It has therefore been chosen to include this effect in the model. From the flow simulations in the Delft Sandstone Member it shows that different geothermal systems closely placed within one reservoir will have pressure interference. From this study it is concluded that multiple geothermal systems can be placed in one reservoir and sustain economic production temperature for over 30 years. Different geothermal systems in one reservoir will however communicate in the reservoir creating both positive and negative effects on flow that are large enough to respectively improve or badly affect the economics of a project. The results of this study will be a base case for further research as it will form a benchmark for future local and regional geothermal studies. Simulations of multiple well configurations to determine optimal well placement can now be performed. This will ensure and provide the foundation for a true roll out of geothermal systems through the western parts of the Netherlands.

geothermal

http://resolver.tudelft.nl/uuid:b175f4a2-1caa-47c6-8a56-2513aa954ce7

2013-06-18

Student theses

master thesis

(c) 2010 Gilding, D.T.