BOX 1.1 Natural Gas
Natural gas is a naturally occurring mixture of hydrocarbons and other compounds. Like petroleum, natural gas is generated by the deterioration of organic materials under anaerobic conditions. It consists primarily of light hydrocarbons (e.g., methane and ethane) with some heavier hydrocarbons (e.g., butane and propane). Impurities (e.g., sulfur dioxide, carbon dioxide, and helium) can also occasionally be present in various concentrations.
helium was soon discovered in trace quantities from a variety of sources, including the atmosphere.
The supply situation changed dramatically in the early 1900s, when helium was found to exist in rather large quantities in the natural gas wells of the midcontinental United States (see Box 1.1 for a description of natural gas). The best known story concerns the exploratory well drilled in 1903 at Dexter, Kansas, which produced a gas that refused to burn. Subsequent analysis of the gases from this and neighboring wells by Cady and McFarland showed that the helium was at concentrations of around 1 percent by volume. Although geologists and oil producers reported a number of natural gas fields from which helium could potentially be produced, interest in commercial recovery did not develop until the onset of World War I. For example, Kamerlingh Onnes obtained the helium for his early 1908 experiments on the liquefaction of helium by a tedious extraction from a mineral source, monazite sands.
The British government became interested in helium as a lifting gas early in War World I. Although not as buoyant as hydrogen, helium would not burn and thus could withstand enemy fire. The British initiated a research program at the University of Toronto, Ontario, in 1915, and a small experimental plant was operating near Hamilton, Ontario, by 1918. No Canadian helium was actually used in warfare, but the separation technology was demonstrated at Hamilton and later at Calgary, Alberta, in 1919 and 1920.
The task of establishing a domestic source of helium was given to the U.S. Bureau of Mines (BOM) when the United States entered World War I. BOM contracted the construction of three helium extraction plants: two at Fort Worth and one at Petrolia, Texas. The three produced about 200,000 scf (5,500 scm) of helium in experimental runs, and 140,000 scf (4,000 scm) of compressed gas was awaiting shipment to Europe at the war's end. It is not surprising that there was no thought given to long-term storage of helium at this point, except as compressed gas in cylinders ready for immediate use.
Cognizant of Germany's relative success with military zeppelins, the U.S. Navy began a program immediately after the war to develop rigid airships as naval weapons. The first full-scale U.S. helium production plant, completed near Fort Worth in April 1921, was based on the experimental wartime plant designed by Linde Air Products. The plant was operated for the Navy under contract by Linde until 1925, when it was turned over to BOM. With the Petrolia gas field nearing exhaustion, the plant was mothballed in 1929, by which time it had produced some 47 million scf (1.3 million scm) of helium. As before, no thought was given to long-term storage in a reserve.
In anticipation of the Fort Worth closure, BOM decided to build a new plant, the first unit of which went into production in April 1929, followed by a second unit in May 1930. This plant, near Amarillo, Texas, subsisted on natural gas from the Cliffside field, which was connected by a 12-mi (19-km) pipeline. The methane produced was pipelined about 7.5 mi (12 km) to Amarillo, where it was used as fuel. The plant could produce as much as 25 million scf (700,000 scm) of helium per year but never operated at full capacity.