Utilization of melting techniques for borehole wall stabilization. [Applied to geothermal well production systems]

Conference · Sat Jan 01 04:00:00 EST 1977

OSTI ID:7318048

Altseimer, J H

A research program on the Subterrene concept based on excavation by melting has been completed. Theoretical and experimental studies were made for a broad range of applications. Most recently, a study of Subterrene deep geothermal well production systems predicted that, compared to rotary-drilled wells, significant cost savings are possible, e.g., 2 and 4 million dollars for 10-km-deep wells and geothermal gradients of 25 and 40 K/km, respectively. It was also concluded that for most wells the rate of penetration of the melting bits should be increased several times over that attained in the Subterrene tests. Subterrene melting penetration tests showed that borehole glass liners can be formed in a wide variety of materials and structural characterization tests showed that tuff glass cylinders can be many times stronger in compression than the parent material. Also, the tests showed that the rock-glass liner permeability decreases rapidly with confining pressure. New melting devices are conceivable that could line rotary-drilled boreholes with rock glass or other materials with resultant improvements in well costs. With emphasis on borehole liners, an overview of Subterrene program results, data on rock-glass liners, and suggestions on how molten materials might be applied to the borehole wall as part of a rotary drilling operation are presented.

• Research Organization: Los Alamos Scientific Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 7318048
• Report Number(s): LA-UR-77-840; CONF-770440-1
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150901* -- Geothermal Engineering-- Drilling Technology & Well Hardware
BOREHOLES
CAVITIES
COST
DRILLING
DRILLING EQUIPMENT
DRILLS
EQUIPMENT
GEOTHERMAL WELLS
GLASS
Geothermal Legacy
LINERS
LINING PROCESSES
MELTING
PHASE TRANSFORMATIONS
ROCK DRILLING
STABILIZATION
SUBTERRENE PENETRATORS
USES
WELL DRILLING
WELLS