Helium is commonly used as a shield gas for non-ferrous welding. Argon can be used instead of Helium and is preferred for certain types of metal. Helium is used for lots of lighter than air applications and Hydrogen is a suitable replacement for many where the flammable nature of Hydrogen is not an issue.
Helium and Argon are commonly used as purge gases thanks to their inertness, but Nitrogen is probably the most widely used purge gas in industrial applications and scarcity of Helium is likely to lead to an increase in use of alternatives for these applications.
Helium is commonly used in controlled atmosphere applications, but Nitrogen offers a cheaper viable option for long-term storage of foodstuffs. Hydrogen offers a number of advantages to Helium for gas chromatography including lower cost, availability through electrolysis of water, and improved sampling speed.
Many chromatography laboratories are actively changing from using Helium to Hydrogen for carrier gas. Ed Connor DR. Prior to joining Peak in February , Ed completed his Dr. To find out more about Peak Scientific's hydrogen, nitrogen and zero air Precision series generators for GC click here or contact us.
Why is there a shortage of helium? Shielding gas for welding Helium is commonly used as a shield gas for non-ferrous welding. Balloons Helium is used for lots of lighter than air applications and Hydrogen is a suitable replacement for many where the flammable nature of Hydrogen is not an issue. In a joint research venture between Durham University and the University of Oxford in the UK, with the financial support of the Norwegian state oil company Statoil, we have used well-established hydrocarbon exploration protocols as a template to develop a similar strategy for helium.
This work has enabled us to begin to answer questions about how and where helium is generated; how it is released from potential source rocks; how it then travels significant distances from source rocks to potential traps; and how helium-rich gas accumulates in the shallow crust, as well as how these accumulations can be destroyed by natural processes. The project is still in its early stages, but we believe our research is an important step towards diversifying the helium supply, so that when another supply crisis occurs, we are better prepared.
There are two stable isotopes of helium: ubiquitous helium-4, which constitutes Helium-3 is used in neutron detectors and is also a candidate fuel for power generation though nuclear fusion. Different rock types produce varying amounts of helium-4, controlled by the original concentrations of uranium and thorium and the age of the rock. Some of the highest accumulations of helium are found in large, stable continental blocks known as cratons that formed in the early Precambrian up to 4. Helium is found in many other geological systems, including groundwater, ancient brines, fluid inclusions in ore deposits, hydrothermal fluids, igneous intrusions and rocks, oil-field brines, lakes, ice sheets, oceanic sediments and coal measures.
To date, however, only a few natural hydrocarbon gas fields contain helium in sufficient concentrations for its extraction to be considered commercially viable. The first economic quantities of helium were discovered in in Dexter, Kansas, US.
However, none of these new helium reserves currently match the concentrations, number of occurrences or estimated reserve volumes associated with the older US fields. From a simplistic sourcing perspective, older rocks will generally have had more time to produce and accumulate helium than younger ones. Therefore, a logical first step in a helium exploration protocol is to identify viable Precambrian-aged crystalline terrains in areas that have remained relatively tectonically stable for long periods of time.
However, age is not the sole determinant of a viable source rock. The helium also needs to have been released from the rock — a process known as primary migration. The primary migration process begins when particles in uranium and thorium-bearing minerals undergo radioactive decay, releasing alpha particles helium-4 nuclei.
While it is not yet known how efficient this escape process is, once helium has diffused out of the mineral it will accumulate in fluid inclusions and fractures within the source rock. For helium to then migrate out of the low-permeability source rocks into overlying layers, another input of energy is required. This typically comes in the form of heat and pressure from tectonic events such as rifting, mountain building or volcanic activity.
We do not fully understand the primary release process; however, we do know that the bulk migration of helium is enhanced by the presence of a carrier fluid or gas. In natural gas formations, high helium concentrations are always associated with high concentrations of nitrogen. The converse is not true, as many nitrogen-rich natural gas sources contain only trace amounts of helium; the explanation being that there are multiple sources of trapped nitrogen in the crust. Analyses have shown that radiogenic helium is consistently associated with nitrogen that has an isotope distribution characteristic of a source in the crystalline basement, indicating that the nitrogen is likely carrying helium out of source rocks.
Early in our research, we sampled well gases from existing helium-producing areas in the midwestern US and southern Canada. More recently, we worked with a helium exploration company, Helium One , to sample helium-rich gas seeps in the Tanzanian section of the East African Rift.
All samples were rigorously analysed for information about the gas composition and the isotopic composition of the separated helium, other noble gases and nitrogen. Most manufacturers could potentially recycle helium but the logistics of doing this would be too difficult and uneconomical. The expense of capturing and purifying the escaped helium far outweighs what it can be sold for. Other main components of balloon gas are nitrogen and oxygen. For some bottling manufacturers — purity is measured at bottling point and a gas certificate is sent with the cylinders if a special mixture is requested.
Depending on the application, the required quality and purity of helium varies. For some scientific applications the required helium purity can be Again, as the helium shortage ended in no priority was set for where helium should be used.
There is nothing stopping science and academic institutions using the mixed gas except the premium cost of re-processing the impure helium to pure helium as high purity is required in science and academia.
How much helium do we have and are we running out? This is difficult to predict as it depends on supply and demand — but no shortage is anticipated.
One manufacturer has advised us they do not foresee any end to helium availability. As an example, a major new helium gas field has been discovered in Tanzania in June Its estimated helium resources may be able to supply 8 years of the current worldwide annual helium consumption. This has been discovered using a new detection technique which will focus on finding new helium reserves instead of obtaining helium from mining natural gas.
Another manufacturer as advised us that to estimate the amount of helium reserves is difficult. Some of this is dependent on finding new reserves such as recently found in Russia and Qatar in , as well as how we use helium i. It has been suggested that one particular project of helium discovery will produce the largest reserves of helium that will be seen. In addition to this, some applications where helium was being used are being developed to use alternative gases such as.
The scare of previous shortages have resulted from a disruption to the supply chain despite reserves being available.
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