NOVEMBER 2007
T
he Problem For those of you who may not have heard
yet, for the past year or so, the price of helium has increased dramatically in most parts of the country, and it’s
becoming more and more difficult to get helium from the few suppliers who refine and supply this gas to local distributors. Demand is very close to outstripping supply creating an apparent
“helium shortage”. This situation has led to the inevitable price
increases which some users can protect themselves against by
using helium recovery systems in their vacuum leak checking operations.
Although helium is the 2nd most abundant element in the
universe, amounting to approximately 20% of all known matter,
it’s relatively rare here on earth. Formed as a by-product of radioactive decay in the Earth’s crust, helium is only found in recoverable quantities in natural gas wells. In theory it is believed
that helium, diffusing through the sedimentary rock layers of the
earth, is swept up by overlying regional aquifers which effectively transport and concentrate it underground into natural gas
well “traps”. But because helium easily diffuses through the sedimentary rock column, high concentrations of helium (>0.4%)
can only be found in a very small number of wells that are capped
with high density rock or crystalline salt deposits. Helium which
does escape the ground is quickly dispersed in the air and eventually floats away into outer space, and is gone forever.
The formation of helium is therefore a slow process which occurs only on a geologic time scale. Unlike hydrogen, which can
be extracted from water, helium is inert and does not
combine with other materials and can’t be synthesized in any significant way, nor can it be distilled from the atmosphere
productively as its concentration in air is only 5.2 ppm. Because
helium retention in natural gas wells requires the presence of high
density rock traps, it is not found in every natural gas well in recoverable quantities. In fact, there is only one small region of the
United States in western Kansas, and the Oklahoma and Texas
Panhandles known as the Hugoton and Panhandle Fields where
helium exists in sufficient concentrations for economically viable
extraction. It is important to note that all helium used in the
United States (and most of the helium used throughout the world)
comes from this one region, and flows through a single 425 mile
Figure 1.
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long pipeline that was built by the US Government in 1960 when
the Helium Act Amendments were passed. (See Figure 1) This
legislation recognized that helium was a rare and strategic natural resource critical to the cold war missile program in which helium is used to pressurize the liquid oxygen and hydrogen
propellants. This legislation encouraged many private gas companies to construct helium extraction facilities to feed this
pipeline, enabling them to sell unlimited quantities of crude helium to the US Government, which was put into long term storage underground in the partially depleted Cliffside gas field near
Amarillo, Texas. This government storage site helped to create the
US Helium industry, making the product available for commercial sale to a variety of users, in adequate supply and at an affordable price.
As already mentioned, the US is by far the largest producer
and exporter of helium. Other known helium reserves include
natural gas wells in Qatar, Algeria, Russia, Canada, China and
Poland, but their capacity to refine and export helium to the rest
of the world is still under development, and behind schedule in
Qatar and Algeria. (See Figure 2) However, the demand for helium outside the United States has been increasing in recent years
mainly due to the rise of the middle class and increasing high
technology manufacturing activities in developing countries.
Helium is used for a wide variety of applications, the largest at
Figure 2.
nearly 30% being the liquid helium cooling of superconducting
magnets used in MRI machines. This market has continued to
grow to meet the universal demand for improved healthcare
throughout the world.As standards of living increase, the need for
helium shielded gas welding has also increased, accounting for
approximately 12% of all helium used. Lifting applications for
blimps and weather balloons amounts to 16%, and the
helium leak checking of sealed components (which is difficult to
quantify) has been estimated at perhaps as much as 12%. Other
significant applications include the manufacture of fiber optics,
semiconductors, rocket launches, gas chromatography and mixed
breathing gas used in deep sea saturation diving. However, helium
filled party balloons are virtually unknown outside the United
States.(See Figure 3)
Why there is a problem -- Higher Helium Prices and Delivery Constraints.
Many of these applications which take advantage of the unique
properties of helium are totally dependent upon a continued uninterrupted supply of helium, at an affordable price. However,
today there are reports of helium shortages and severe price increases that appear not to be caused by one single event. We believe it is fair to say that in recent years, with the emergence of the
global economy, the worldwide growth in demand for helium has
increased. When you couple this increased demand with some
helium pipeline pressure problems, and some rather brief scheduled and unscheduled downtime at a few of the plants where helium is refined, as well as a lengthy delay in the new helium
sources in Qatar and Algeria being brought on line you find a
“Perfect Storm” of market forces which have driven up the price
of helium during the past year by 10% to 30% or more. Others
report that helium prices have been increasing from 10% to 20%
for the last three years. It has even been rumored that helium
prices in California could possibly triple. Adding insult to injury,
the helium supply shortage has resulted in some long standing
customers of helium being placed on allocation schedules, which
prevents them from increasing the amount of helium they can
place on order. Major consumers of helium, such as MRI manufacturers and NASA have priority over all other customers for
helium at this point. Should their needs increase, or supply line
problems develop, it will be those customers on the lower end of
the priority list, such as those using helium for leak checking,
who will suffer delivery interruptions. However, everyone will
bear the brunt of price increases if or when they occur. In 2006,
the Macy’s Thanksgiving Day Parade flew fewer helium filled
balloons in response to the worldwide shortage of helium. It is
safe to say that over the next several years, the US will face difficulty to cover domestic demand and to supply the increasing
international consumption. (See Figure 4)
Need for Conservation
Helium refiners are currently outputting all the helium that they
can, and the US Government helium storage facility managed by
the Bureau of Land Management supplied 2.1 billion cu ft of helium to the market in 2006, which is its maximum sustainable
Figure 3.
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November 2007 • Gas Delivery & Diagnostics
FREE
Helium!
Figure 4.
well almost....
rate. There is very little if any excess helium refining capacity
and domestic supplies of crude helium are growing ever tighter
as the existing known reserves and the government helium storage facility are being drawn down. Because of the current unsustainable market conditions of higher than ever worldwide
demand for helium, increasing helium cost, and uncertain supply
(which is likely to continue for another year or more until overseas sources are fully developed), prices will most likely continue
to rise. Currently, helium prices have been quoted at around $300
per T-size cylinder for ultra high purity helium, and around $100
per cylinder for industrial grade helium (which is sufficient for
leak checking work.)
As a result of these unsettled market conditions it makes sense
for large volume users of helium to conserve this material as best
they can in order to shield their production against unexpected
helium cost increases or supply interruptions. For companies performing helium leak tightness checks on sealed parts, one way for
them to reduce their helium expense and conserve their supply of
this gas is to use a helium charging and recovery system which
basically recovers the helium charged inside the part for leak
checking and reuses it on the next part to be tested. ULVAC has
built many of these systems which can achieve production speed
recovery rates in excess of 98%, which reduces helium leak
checking expenses dramatically. It’s important to realize that this
equipment reuses the helium repeatedly, but it does not recycle
the gas, nor strip it of any contaminants that it might pick up along
How about 98% free!
Reduce Leak Checking Costs.
Ulvac’s Helium Recovery and Charging System
can save you thousands of dollars a month
by recovering up to 98% of your lost helium.
The system maintains helium purity and
concentration for reliable leak checking results.
Operation is simple, automatic and seamlessly
integrated into your existing leak checking
operation.
With hundreds installed, leave it to Ulvac, to
recharge your helium and your bottom line.
ULVAC Technologies, Inc.
Methuen, MA
Tel.: 978-686-7550
Web: www.ulvac.com
Figure 5.
Gas Delivery & Diagnostics • November 2007
www.vactechmag.com or www.vtcmag.com
18K
$
Leak
Detection
For $18,000 you can get a full-featured
Heliot 700 helium leak detector with
color touch screen.
The Heliot features onscreen troubleshooting
capabilities and a multiple valve design for
ultimate sensitivity – 10-12 Torr-l/s. Standard
unit prices include:
•
•
•
•
Rotary Vane Pump - $18,000
Dry Diaphragm - $19,995
Large Rotary Pump - $21,070
Dry Scroll Pump - $26,865
the way. Currently there is no supply return path from retail customers back to helium refiners as a common practice, therefore
recycling in the strictest sense of the word is not an option. Rather,
local reuse is the only currently available alternative for the majority of users, and this can be accomplished with a helium charging and recovery system.
How helium recovery systems work
Typically, when a closed part such as a radiator or condenser
coil, or a refrigeration or air conditioning compressor is charged
with helium for leak tightness checking, it is fitted with quick disconnect helium tight couplings and is simply filled with a certain
concentration of helium to a particular pressure and sealed off.
The part is then sniffed or placed inside a vacuum chamber system for leak checking with a mass spectrometer based helium
leak detector. At the conclusion of the test, the part is simply
vented and the helium escapes into the room where it becomes
lost forever eventually to the outside air and then eventually up
into outer space. However, with a helium charging and recovery
system, that helium would be removed from the part via a recovery line connected to a helium compressor, which would
pump it into a high pressure storage tank where it would be ready
for reuse on the next part to be tested. (See Figure 5). Conceptually, this is the extent of the process. However in actual practice
this approach contains a few weak points. For example, unless the
part is pre-evacuated before being charged with helium, the air
contained inside the part will also be recovered by the compressor, and will dilute the helium concentration over time as more
and more parts are leak checked. Furthermore, the use of a single compressor to remove all the helium from the part will actually leave a lot of helium behind – stranded inside the part. These
two pitfalls in recovery system design can be responsible for less
than optimum recovery rates and can also lead to the need for
frequent compressor maintenance.
An improved helium recovery system design (shown in Figure
6) would be one that first pre-evacuates the part to remove most
of the air contained inside the part, thus preventing helium dilution to a great extent. While at this first step in the process (once
For $18K leak detection
email us at:
[email protected]
ULVAC Technologies, Inc.
Methuen, MA
Tel.: 978-686-7550
Web: www.ulvac.com
Figure 6.
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November 2007 • Gas Delivery & Diagnostics
the part is evacuated), a smart idea would be to check for gross
leaking parts by conducting a brief rate of rise test. This quick
check would rule out the possibility of a gross leak in the part,
such as a missing or incomplete weld, or perhaps a bad connection to the charging gun. Once the rate of rise test has been passed,
helium tracer gas would then be charged inside the part from the
high pressure reservoir tank. After checking for leaks by sniffing
or placing the charged part in a vacuum chamber for more sensitive leak testing, the part is then connected to the helium recovery line. The overpressure of helium tracer gas is first
exhausted into a low pressure recovery tank, and then a two-stage
helium tight oil sealed rotary vane pump exhausts the remaining
helium out of the part and into a low pressure recovery tank. The
part is then vented with room air and disconnected from the recovery line. The recovered helium in the low pressure tank is subsequently pumped to the high pressure tank by a helium tight
compressor where it is ready for charging the next part to be
tested. In large recovery systems, two helium compressors connected in parallel, but running alternately is a good idea to extend their mean time between maintenance intervals. In high
production environments, continuous duty short cycling of dry
running helium piston compressors can be very tough on these
compressors.
Under ideal conditions 98% of the charged helium tracer gas
is recovered by the system. But this means that 2% is lost – either
left behind inside the part where it could not be pumped out in
timedue to cycle time demands8, or falls victim to void volume
losses while connecting and disconnecting the charging or recovery lines. The charged helium tracer gas is seldom 100% pure
helium. This means that not only will the volume of gas in the
system be reduced because of the 2% loss, but the concentration
of helium in the tracer gas will be incrementally reduced as a
function of each part tested. To compensate for these losses, a helium concentration monitor is incorporated into to the system design which constantly monitors the helium concentration in the
tracer gas contained in the high pressure tank. If necessary, a solenoid valve opens to raise the helium concentration in the high
pressure tank, or opens to a nitrogen tank to adjust the volume of
gas charged into the system.
About cycle times and production rates
Using vacuum pump assisted helium recovery from a part into
a low pressure tank can increase the helium recovery rate close
to 98%, but this step requires more time than simply
venting the part (which recovers nothing) or exhausting the part
using a compressor alone, which recovers perhaps up to 90%.
In most manufacturing facilities, smaller parts are typically
produced at higher manufacturing speeds, whereas parts with
larger internal volumes are usually produced at a slower tact time.
This means that the additional time required for the
vacuum pump assisted helium recovery from a large part
usually balances out against the slower production speed at which
the larger parts are produced.
Gas Delivery & Diagnostics • November 2007
www.vactechmag.com or www.vtcmag.com
Figure 7.
Energy balance issues
Clearly, operation of two vacuum pumps, two helium
compressors, a helium concentration monitor, numerous
solenoid valves and a PLC controller consumes electricity, which
is not free. However, compared to the cost savings of reducing helium costs by up to 98%, the cost for the electricity typically
required to operate a recovery system is trivial by
comparison. For example, on a per part basis, assuming a
radiator with a 4 liter internal volume is charged with 50%
helium tacer gas to a pressure of 30 psi, the value of the 4 liters
of helium contained in that part would be worth approximately
$1.20. Further assuming the cost for electricity is 13 cents per
kWhr, and it takes 1 minute to charge and recover 98% of the helium from this radiator, the cost for electricity would be roughly
only 2 cents. This means the net savings in helium cost per part
would be in the neighborhood of $1.16. Conversely, the cost for
helium per part drops from roughly $1.20 to just 4 cents.
Case studies
Because ULVAC is a Japan based company with major
operations throughout Asia, where helium availability has long
been a problem, the company has a wealth of experience in
China, with numerous helium charging and recovery systems installed there. Now that the price of helium has increased here domestically for both large and mid-size users to the point where
purchase of a helium recovery system can be amortized in about
a year or less, interest in these systems is increasing.
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November 2007 • Gas Delivery & Diagnostics
meet their manufacturing needs in their plants throughout the
world. Helium leak detection has helped them improve their
product quality, while the use of helium charging and recovery
equipment has successfully lowered their operating cost. Their
current annual production exceeds 10 million units/year, and use
of helium charging and recovery systems have helped them save
millions of dollars per year. (Figure 9)
Smaller production operations can also be candidates for
helium recovery systems. The economics of amortization can be
calculated based upon an average starting price of $60,000 for
this equipment.
In Closing
Figure 8.
Figure 9.
Sanyo in Mexico manufactures residential refrigerators. These
Freon compressor circuits are helium leak tested by sniffing prior
to filling with Freon to ensure leak tightness and long product
life. To save on leak checking costs Sanyo recently purchased a
helium charging and recovery system similar to that shown in
Figure 7.
Like Sanyo, Haier Refrigerator Factory in China also builds
refrigerators. Back in 1996 they wished to improve their
product quality, and switched from Freon leak detection to
helium leak detection of their refrigerator circuits. In Haier’s case,
the average internal volume of their Freon circuits is 5 liters,
which is charged to 8 bar (116 psi), which equates to 40 std liters
of helium being charged into their unit for leak testing. Their local
price for industrial grade helium is equivalent to $133 per 5,500
liter tank (200 cu ft). This is equivalent to 2.4 cents per liter, therefore 40 liters would cost $0.96. Their annual production of refrigerators is 300,000 units, which means if they were venting
the helium to the atmosphere, they would be wasting the equivalent of $288,000 per year in helium. However, with 6 recovery
systems operating at a 98% recovery rate, they wind up saving
$282,240 in helium costs, and actually spending just $5,760 in actual helium.(Figure 8)
In the same application, but with air conditioners, Gree Air
Conditioner, the largest air conditioner supplier in the world has
purchased 50 helium charging and recovery systems to date to
Helium is a unique material that is used for many high tech
applications. Less desirable substitutes for helium can be found
for certain applications, but not all. For example, today it would
be impossible to manufacture silicon wafer based semiconductors, or to do low temperature superconductivity work or low temperature research below 17 kelvin (-256°C), or to launch rockets
(including the space shuttle) into orbit without helium. And the
vast majority of MRI machines would no longer work without
liquid helium.
In an attempt to recoup the $1.4 Billion debt incurred by stocking the Federal Helium Reserve, the US Government passed the
1996 Helium Privatization Act which requires the sale of the 35
billion cu ft of helium currently in storage at the Federal Helium
Reserve by the year 2015. It is currently predicted that by the year
2020, the price of helium will further increase because the United
States will be forced at that point to begin importing helium, most
likely from Qatar and Algeria, because the private and Federal
Helium Reserves in the United States will be drawn down to the
point where production will no longer be able to keep up with
domestic consumption. Helium deposits exist elsewhere throughout the world (and the U.S.) but helium is a curious commodity
in that discovery of reserves and production of helium is a byproduct of the demand for natural gas, not helium. Although
there’s plenty of natural gas left throughout the world, not all of
it contains helium in sufficiently high concentration to make commercial extraction economically viable. It is likely to expect that
the private gas suppliers will sort out this helium dilemma without further government intervention, and will make a profit while
doing so. But as an insurance policy, the government is keeping
some 565 million cu ft of helium in reserve, just in case, and has
tasked the National Academy of Sciences to study and report on
the helium market for any substantial adverse effects that its
health and well being might have on the U.S. scientific, technical, biomedical or national security interests. A few things are
certain — US Helium supplies are running out, and at some point
the US will be forced to import helium, just as we do today with
natural gas, and then the price for helium will increase even
further. However, the use of these straightforward and simply designed helium charging and recovery systems is one way
that manufacturing companies can protect themselves against the
threats of loss of supply or unexpected price increases for helium.
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References
Helium – http://en.wikipedia.org/wiki/Helium
The Helium Market – Demand Floats Higher as Supplies Sink,
Maura D. Garvey, Cryogas International, Vol. 44, No., 9. October 2006
Helium Exploration – A 21st Century Challenge. Steven J. Maione.
Paper presented at the Houston Geological Society Dinner, February
23, 2004 http://www.hgs.org/en/art/?162
Helium – Mineral Information Institute report.
http://www.mii.org/Minerals/petrohelium.html
Edward Frankland6 - http://en.wikipedia.org/wiki/Edward_Frankland
Helium – The Sun Gas, Ebbe Almqvist, Cryogas international, Vol. 44,
No. 9. October 2006.
Challenges to the Worldwide Supply of Helium in the Next Decade. D.
M. Smith et al., Air Products & Chemicals, Inc. paper presented at the
2003 Cryogenic Engineering Conference.
The Federal helium Program: The Reaction Over an Inert Gas. James
E. Mielke. CSR Report for Congress 95-197.
http://www.ncseonline.org/NLE/CRSreports/Natural/nrgen11.cf
m?&CFID=8020441&CFTOKEN=57798360
Where has all the helium gone? Laura Thesiss, Bureau of Land Management National News, January 18, 2007
http://www.blm.gov/wo/st/en/infonewsroom/2007/January/NR07
01_2.print.html
Evan Sohm received a BA degree in Interdisciplinary Science
from Eisenhower College in 1977. He has worked in the vacuum
industry since 1980 and prior to joining ULVAC Technologies,
Inc. in 2000 as Product Marketing Manager for Vacuum Components, he held several positions with both Leybold and Balzers.
Chris Goebel, Sr. Director of Sales and Marketing for ULVAC
Technologies, Inc. earned his BS degree in Mechanical and Electrical Engineering from the University of New Hampshire in 1987.
Before joining ULVAC, he worked as Field Service and Product
Engineering Managers for BTU International. At ULVAC he has
held positions in Engineering, Operations, & Customer Service.
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