In geothermal wells, energy is extracted by circulating water through a network of connected fractures. Highly conductive fractures negatively impact the reservoir sweep efficiency as flow is preferentially concentrated in these fractures and therefore bypasses the majority of the thermal reservoir. Further, the preferential flow can lead to a feedback loop that exacerbates this thermal short-circuiting: cooling of the rock adjacent to the concentrated flow results in rock contraction, increasing the fracture width and conductivity, and results in more preferential flow. Thermal short-circuiting is responsible for thermal breakthrough, decreasing energy extraction efficiency, and reducing service life. Thus, there is a significant need for a method to stop or reduce the short-circuiting and improve energy sweep in geothermal reservoirs.
Researchers at the University of New Mexico are developing innovative polymer-based materials that can be injected into fractures at targeted locations away from geothermal wellbores to modify the fracture permeability and consequently control the resulting flow rate through the fracture and the heat exchange with the formation. The polymer-based material is designed to displace water from the fracture and harden to form a porous material that bonds to the rock formation surface. Porous material allows control of the resulting permeability of the fracture and prevents the treatment from completely sealing the fracture.
These polymer-based injectates offer an innovative engineering solution for problems associated with the preferential flow that can lead to thermal short-circuiting. The nano-modified polymer injectate could be used during the initial stimulation and development of the enhanced geothermal system (EGS) fracture network to tune the fracture network and optimize thermal productivity. The capability to modify fracture permeability and thereby limit thermal short-circuiting addresses one of the most critical challenges that must be overcome in order for EGS to be economically successful.
- Can be selectively placed in large fractures that are responsible for thermal short-circuiting
- Ability to control the flowability of the polymer injectate
- Engineered porosity of polymer allows resulting fracture permeability to be adjustable
- Bonds to rock formation and is therefore not displaced by subsequent flow during operation
- Enhanced Geothermal Systems (EGS)
- Geothermal Wells
- Lost Circulation
UNM Rainforest Innovations has filed intellectual property on this exciting new technology and is currently exploring commercialization options. If you are interested in information about this or other technologies, please contact Arlene Young at firstname.lastname@example.org or 505-272-7886.
About UNM Rainforest Innovations
As the technology-transfer and economic-development organization for the University of New Mexico, UNM Rainforest Innovations protects and commercializes technologies developed at the University of New Mexico (UNM) by filing patents and copyrights and transferring the technologies to the marketplace. We connect the business community (companies, entrepreneurs, and investors) to these UNM technologies for licensing opportunities and the creation of startup companies. Visit http://innovations.unm.edu/
Name: Andrew Roerick