Industrial gas
Industrial gases are used in a wide range of industries, which include oil and gas, petrochemicals, chemicals, power, mining, steelmaking, metals, environmental protection, medicine, pharmaceuticals, biotechnology, food, water, fertilizers, nuclear power, electronics and aerospace.
This business covers the sale or hire of gas cylinders and associated equipment to tradesmen and occasionally the general public.
A wide variety of hand-carried small gas containers, which may be called cylinders, bottles, cartridges, capsules or canisters are available to supply LPG, butane, propane, carbon dioxide or nitrous oxide.
The first gas from the natural environment used by humans was almost certainly air when it was discovered that blowing on or fanning a fire made it burn brighter.
when they discovered the potential to transport gas seeping from the ground in crude pipelines of bamboo to where it was used to boil sea water.
[5] Early understanding consisted of empirical evidence and the protoscience of alchemy; however with the advent of scientific method[6] and the science of chemistry, these gases became positively identified and understood.
The history of chemistry tells us that a number of gases were identified and either discovered or first made in relatively pure form during the Industrial Revolution of the 18th and 19th centuries by notable chemists in their laboratories.
[20] For example, carbonated water was being made from 1772 and commercially from 1783, chlorine was first used to bleach textiles in 1785 [21] and nitrous oxide was first used for dentistry anaesthesia in 1844.
In 1895 refrigeration compression cycles were further developed to enable the liquefaction of air,[25] most notably by Carl von Linde[26] allowing larger quantities of oxygen production and in 1896 the discovery that large quantities of acetylene could be dissolved in acetone and rendered nonexplosive allowed the safe bottling of acetylene.
To achieve the required low distillation temperatures, an Air Separation Unit (ASU) uses a refrigeration cycle that operates by means of the Joule–Thomson effect.
The larger industrial gas companies have often invested in extensive patent libraries in all fields of their business, but particularly in cryogenics.
Air Separation and hydrogen reforming technologies are the cornerstone of the industrial gases industry and also form part of the technologies required for many fuel gasification ( including IGCC), cogeneration and Fischer-Tropsch gas to liquids schemes.
Hydrogen has many production methods and may be almost a carbon neutral alternative fuel if produced by water electrolysis (assuming the electricity is produced in nuclear or other low carbon footprint power plant instead of reforming natural gas which is by far dominant method).
Simpler gas separation technologies, such as membranes or molecular sieves used in pressure swing adsorption or vacuum swing adsorption are also used to produce low purity air gases in nitrogen generators and oxygen plants.
Some gases are simply byproducts from other industries and others are sometimes bought from other larger chemical producers, refined and repackaged; although a few have their own production processes.
Related services and technology can be supplied such as vacuum, which is often provided in hospital gas systems; purified compressed air; or refrigeration.
Some industrial gas companies may also supply related chemicals, particularly liquids such as bromine, hydrogen fluoride and ethylene oxide.
A few gases are vapors that can be liquefied at ambient temperature under pressure alone, so they can also be supplied as a liquid in an appropriate container.
[30] The major industrial gases can be produced in bulk and delivered to customers by pipeline, but can also be packaged and transported.
In United States of America, no official regulation of color coding for gas cylinders exists and none is enforced.
In practice, "industrial gases" are likely to be a pure compound or a mixture of precise chemical composition, packaged or in small quantities, but with high purity or tailored to a specific use (e.g. oxyacetylene).
Materials such as LPG and LNG are complex mixtures often without precise chemical composition that often also changes whilst stored.
These demarcations are based on perceived boundaries of these industries (although in practice there is some overlap), and an exact scientific definition is difficult.
Similarly, projects harnessing Landfill gas or biogas, Waste-to-energy schemes, as well as Hydrogen Production all exhibit overlapping technologies.
[34] These elements are all primordial apart from the noble gas radon which is a trace radioisotope which occurs naturally since all isotopes are radiogenic nuclides from radioactive decay.
[35]) The elements which are stable two atom homonuclear molecules at standard temperature and pressure (STP), are hydrogen (H2), nitrogen (N2) and oxygen (O2), plus the halogens fluorine (F2) and chlorine (Cl2).
Radon is a trace naturally occurring radioactive material (NORM) encountered in the air processed in an ASU.
