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Helium is produced in the natural environment continually by the radioactive decay of uranium and escapes into the atmosphere. Since the concentration of helium in air is very minimal, extraction of helium from air is not economically viable. Commercially, it is available from natural gas deposits. At present, the majority of the helium produced in the world comes from the United States.
Most helium occurs as helium-4. Some trace amounts of helium-3 occur in nature with helium-4, and as a result of nuclear reactions. Crude helium usually contains >50% helium (50–70% is typical); the remainder is usually nitrogen, with some hydrogen, hydrocarbons and methane. High-purity helium contains 99.995% or more helium. Helium is typically transported as a liquid in ISO-certified cryogenic containers for longer distances. It can be distributed in large quantities of over 25,000 normal cubic meters. For short distances, it is transported in tube trailers, high-pressure cylinders, or liquid dewars from local trans-fill stations.
About 71% of world helium capacity is located in the United States, with nearly all of the remaining capacity in Algeria, Russia, Qatar and Poland. A small unit may also operate in China. World demand for helium in 2007 is estimated to have been on the order of 6.0 billion standard cubic feet.
The following pie chart shows world resources of helium:
In spring 2006, increasing demand coupled with delayed start-ups of plants in Algeria and Qatar led to significantly higher operating rates at existing helium plants. Capacity utilizations peaked at over 90% compared with the typical mid-80% range. Under these conditions, the U.S. Bureau of Land Management encountered operating difficulties in its pipelines. Also, there were planned maintenance shutdowns by some of the major plants. All of these conditions contributed to a helium shortage situation that affected helium consumers worldwide. The helium market is expected to be in short supply through 2010.
Future growth in consumption of helium is expected to be driven by demand from electronics manufacturers in China, the Republic of Korea and Taiwan. Semiconductor manufacturing, flat panel display manufacturing and optical fiber manufacturing are all significant consumers of helium in Asian markets. While worldwide demand is only expected to grow by 3–5% per year, demand in these countries is growing by 20–40%. With high-tech manufacturing shifting to Asian countries, the U.S. share of worldwide demand is expected to gradually decline. |
