The 10-pound sonic tool is intended to remove scale from gas storage wells.
MORGANTOWN, WV - Natural gas companies
looking for better ways to unclog the wells they use to
withdraw gas from underground storage reservoirs may
soon be getting "good vibes" from a low-cost sonic
A Department of Energy-sponsored team of companies
led by Furness-Newburge Inc. of Versailles, KY, has
produced a prototype of a system that uses sound waves
to remove inorganic matter and other debris that clog
the perforations of gas wells.
The technology has the potential to increase
significantly the efficiency at which natural gas is
withdrawn from storage reservoirs, making a larger
amount of gas available to consumers during the winter
The prototype was developed through a cooperative
agreement between Furness-Newburge, Nicor Technologies
and TechSavants Inc., both of Naperville, IL, Baker
Atlas, Houston, TX, and the department's National Energy
Composed of an oscilloscope, a power supply, a wire
line reel for the power cable, an acoustical transducer,
a portable generator and waterproof connections, the
device is about two feet in length, two inches in
diameter, and weighs about 10 pounds.
The tool is lowered into a well where it emits
relatively low-frequency, high-intensity directed sound
waves. After a relatively short time, the sound waves
force scale surrounding the well's opening to fall off.
"Who would have thought that the Navy acoustical
training I received in 1966 would be used to clean out
gas wells!" said Jim Furness, principle investigator and
partner at Furness-Newburge.
The basis for this device stems from a process that
Furness helped develop using acoustics to catalyze ozone
and peroxide to prevent air pollution in foundries.
The technology is not ultra-sound, Furness points
out, "People can hear the sound used for the process."
The device is tunable within the range of subsonic to
About two years of laboratory and bench-scale
development yielded a prototype that achieved impressive
results during testing last year at the Bashore No. 1
Observation Well, operated by Nicor Gas near Pontiac,
IL. More extensive field tests need to be performed
along with additional laboratory work before the tool
can be used commercially, but results so far have been
On average, more than 17,000 gas storage wells lose 5
percent of their ability to inject and withdraw gas from
underground storage fields each year. A Department of
Energy-Gas Research Institute study found that inorganic
precipitate or scale was a leading cause of the problem.
Inorganic matter such as calcium carbonate coats a
well's openings from which gas is withdrawn. Over time,
production can decline to the point where over half of
the field's deliverability can be lost. The gas industry
spends between $60 million and $100 million a year
trying to correct this problem.
Water analyses were conducted during the field tests
demonstrated the device's effectiveness in removing key
constituents found in storage well deposits. Water
samples collected after the sonication tool was used
were compared with samples taken two months earlier. The
water chemistry indicated a significant increase in
mineral salts as well as increased levels of suspended
matter - signs that the sonic cleaning device was doing
The amount of calcium, magnesium, iron, and
bicarbonate in solution increased by 100 percent, 60
percent, 60 percent, and 5,300 percent, respectively,
after sonication. The amount of suspended solids also
increased by 230 percent after sonication.
The acoustic portion of the tool is expected to sell
for less than $15,000 and is compatible with standard
wire-line equipment used routinely in day-to-day field
The second phase of the research will begin this
summer. Along with improving the tool so that it can
operate with more rugged field handling, more field
testing will be done in different types of gas storage
reservoirs. Also, more definitive testing, such as
gas-pressure changes, will be performed to better
quantify the system's performance.