PDF Publication Title:
Text from PDF Page: 036
Review of EGS and Related Technology – Status and Achievements Chapter 4 437 Germany – Falkenberg. The Falkenberg test site was established in northeastern Bavaria in 1978, at a location where the Falkenberg granite essentially extends to the surface. The aim was to conduct fundamental in situ hydromechanical experiments at small depths with a high degree of observational control, which would be relevant to the understanding of HDR systems. The research program at Falkenberg lasted until 1983 (Tenzer, 2001). The principal experiments were aimed at determining the hydromechanical properties that hydro fractures created in jointfree portions of the wellbore. A largescale zone was stimulated using packers in an interval free of joints in the drillhole HB4a in the depth range 252255 m. Six further boreholes intersected the fracture that propagated during this stimulation. The creation of the hydro fracture itself is of particular interest, because it proved that fresh hydrofractures can be propagated over significant distances in fractured crystalline rock. This was contrary to the conventional wisdom that said fluid leakoff into the natural fracture system would prevent this from happening. The fracture was initiated in 1979 by injecting 6 m3 of water into borehole HB4a at a rate of 3.5 kg/s, with a breakdown pressure of 18 MPa. Assuming a pennyshaped crack geometry and allowing for leakoff, a fracture radius at shutin of 44 m and a maximum width of 0.62 mm are inferred. Televiewer images of the induced fracture obtained in several neighboring boreholes indicate multiple parallel fractures near the injection borehole, although it seems that only one of these extended beyond 20 m. At borehole PB8 – about 2 m from the injection point – eight parallel fractures are evident within a zone 1.3 m thick; whereas, at 11 m (borehole SB5), only two fracture traces are evident. At more distant boreholes, ranging up to 50 m from the injection well, only one fracture trace is visible. Multiple fracture growth is commonly seen in sedimentary rocks, where it is often associated with high flow impedance. Microseismicity occurring during the injections was monitored by four downhole, threecomponent seismometers installed in neighboring boreholes. The successful detection of 16 of the induced events concurs with the intersection depth of the created fracture and the boreholes, suggesting a planar structure that strikes EW, dipping 45° to the south. The fracture was extended in 1981 with a 33 m3 injection, and again in 1983 with 52 m3. Numerous inflation/deflation cycles were made during the intervening periods, though always involving volumes smaller than the previous “extension” injection. An extensive program of hydraulic tests was undertaken during the project run time. The longest was a 14 h circulation at 3.4 kg/s, during which a thermal drawdown of 1°C was determined. The variation of fracture hydraulic aperture and transmissivity as functions of inflation pressure were investigated and compared with measurements of mechanical aperture taken with a specially developed caliper sonde. • In the Falkenberg project, a fracture believed to be artificial was stimulated from a well (HB4a) at a depth of 450 m. • Seven additional wells were subsequently drilled in a pattern above the fracture. • Several of these wells intercepted the fracture to the extent that small amounts of water could be circulated through the fracture, and extensive hydraulic and rock mechanical experiments could be conducted.PDF Image | Review of EGS and Related Technology
PDF Search Title:
Review of EGS and Related TechnologyOriginal File Name Searched:
egs_chapter_4.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |