Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Geothermal drilling: High-power laser weakens and fractures hard rock

14.02.2019

Geothermal heat is a renewable energy source, low in emissions and capable of assuming part of the base load in the energy mix. When drilling deep into the earth's crust, the temperature rises by an average of about three degrees Celsius per 100 meters. However, in deep geothermal drilling the drill bits encounter different materials, including hard rock.

Hard rock can only be drilled with low rates of penetration and the drill bit wears more quickly. The cost can be pro-hibitive, frequently preventing investors from going ahead with deep geother-mal projects. The Fraunhofer IPT has therefore developed a method for laser-assisted mechanical drilling of hard rock.


The Aachen researchers have set up a test stand with a laser that achieves a light output of up to 30 kilowatts.

Photo acknowledgment: Fraunhofer IPT


Drill bit of the laser drill string with emerging laser water jet.

Photo acknowledgment: Fraunhofer IPT

In the newly developed process, the researchers equipped the mechanical drill with a high-performance laser whose energy is guided onto the rock via a water-jet.

This makes it possible to weaken the material immediately before the drilling process takes place and facilitates subsequent mechanical removal by the drilling tool. The water-jet not only guides the laser beam to the rock face, but also prevents contamination and damage of the sensitive laser optics.

In order to increase the rate of penetration of the drill bit and to preserve its cutting edge, it is necessary to introduce additional energy into the borehole. Since different and often unpredictable materials have to be processed as the drilling depth increases, the flexible adjustment of the laser output power makes it a particularly efficient tool.

Successful tests of the hybrid tool

In the machine shop at the Fraunhofer IPT, the researchers in Aachen have set up a test rig with a laser capable of an optical output of up to 30 kilowatts. In laboratory tests, the project partners tested the process and made preparations for its transfer to the actual application:

The laser weakened sandstone, granite and quartzite, all of which are hard rocks with a strength of more than 150 megapascals, by up to 80 percent.

In the next step, the engineers used the laser on the drilling rig in a specially developed drill string and, in collaboration with the International Geothermal Centre Bochum, successfully tested the new tool under realistic conditions in field trials.

In future research projects, the partners intend to further enhance the distribution of the laser power and add digital sensors to the hybrid tool in order to obtain feedback from the drilling process and thus to be able to react to changes along the drilling path.

Cost-effective geothermal drilling for the production of regenerative energy

The powerful drilling system will help to reduce the cost of deep geothermal drilling in the future and enable geothermal energy to be exploited as an inexhaustible energy source. This form of energy can take over part of the base load in the energy mix and can support other renewable sources such as sun, wind and water in a comparatively environmentally friendly compared to fossil fuels.

Project Consortium

- Fraunhofer Institute for Production Technology IPT, Aachen
- GZB International Geothermal Centre Bochum e.V.
- Herrenknecht Vertical GmbH, Schwanau, Germany
- IPG Laser GmbH, Burbach, Germany
- KAMAT Pumpen GmbH & Co KG, Witten, Germany
- Synova S.A. (associated partner), Duillier, Switzerland

The LaserJetDrilling research project was funded by the Federal Ministry for Economics Affairs and Energy (BMWi) and supervised by the PTJ (funding number: 0325784A).

Wissenschaftliche Ansprechpartner:

Florian Schmidt M.Sc.

Fraunhofer-Institut für Produktionstechnologie IPT
Steinbachstraße 17
52074 Aachen, Germany

florian.schmidt@ipt.fraunhofer.de

Weitere Informationen:

https://www.ipt.fraunhofer.de/en/Press/Pressreleases/20190214_geothermal-drillin...

Sara Vogelsang | Fraunhofer-Institut für Produktionstechnologie IPT

More articles from Earth Sciences:

nachricht New sensor could shake up earthquake response efforts
11.07.2019 | DOE/Lawrence Berkeley National Laboratory

nachricht NASA satellites find biggest seaweed bloom in the world
09.07.2019 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Megakaryocytes act as „bouncers“ restraining cell migration in the bone marrow

Scientists at the University Würzburg and University Hospital of Würzburg found that megakaryocytes act as “bouncers” and thus modulate bone marrow niche properties and cell migration dynamics. The study was published in July in the Journal “Haematologica”.

Hematopoiesis is the process of forming blood cells, which occurs predominantly in the bone marrow. The bone marrow produces all types of blood cells: red...

Im Focus: Artificial neural network resolves puzzles from condensed matter physics: Which is the perfect quantum theory?

For some phenomena in quantum many-body physics several competing theories exist. But which of them describes a quantum phenomenon best? A team of researchers from the Technical University of Munich (TUM) and Harvard University in the United States has now successfully deployed artificial neural networks for image analysis of quantum systems.

Is that a dog or a cat? Such a classification is a prime example of machine learning: artificial neural networks can be trained to analyze images by looking...

Im Focus: Extremely hard yet metallically conductive: Bayreuth researchers develop novel material with high-tech prospects

An international research group led by scientists from the University of Bayreuth has produced a previously unknown material: Rhenium nitride pernitride. Thanks to combining properties that were previously considered incompatible, it looks set to become highly attractive for technological applications. Indeed, it is a super-hard metallic conductor that can withstand extremely high pressures like a diamond. A process now developed in Bayreuth opens up the possibility of producing rhenium nitride pernitride and other technologically interesting materials in sufficiently large quantity for their properties characterisation. The new findings are presented in "Nature Communications".

The possibility of finding a compound that was metallically conductive, super-hard, and ultra-incompressible was long considered unlikely in science. It was...

Im Focus: Modelling leads to the optimum size for platinum fuel cell catalysts: Activity of fuel cell catalysts doubled

An interdisciplinary research team at the Technical University of Munich (TUM) has built platinum nanoparticles for catalysis in fuel cells: The new size-optimized catalysts are twice as good as the best process commercially available today.

Fuel cells may well replace batteries as the power source for electric cars. They consume hydrogen, a gas which could be produced for example using surplus...

Im Focus: The secret of mushroom colors

Mushrooms: Darker fruiting bodies in cold climates

The fly agaric with its red hat is perhaps the most evocative of the diverse and variously colored mushroom species. Hitherto, the purpose of these colors was...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

Flying Laptop satellite mission extended by two years - Successfully in orbit since July 14, 2017

16.07.2019 | Physics and Astronomy

New safer, inexpensive way to propel small satellites

16.07.2019 | Power and Electrical Engineering

UCI electrical engineering team develops 'beyond 5G' wireless transceiver

16.07.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>