Industrial gasIndustrial gases are the gaseous materials that are manufactured for use in industry. The principal gases provided are nitrogen, oxygen, carbon dioxide, argon, hydrogen, helium and acetylene, although many other gases and mixtures are also available in gas cylinders. The industry producing these gases is also known as industrial gas, which is seen as also encompassing the supply of equipment and technology to produce and use the gases. Their production is a part of the wider chemical Industry (where industrial gases are often seen as "specialty chemicals").
Wood gasWood gas is a fuel gas that can be used for furnaces, stoves, and vehicles. During the production process, biomass or related carbon-containing materials are gasified within the oxygen-limited environment of a wood gas generator to produce a combustible mixture. In some gasifiers this process is preceded by pyrolysis, where the biomass or coal is first converted to char, releasing methane and tar rich in polycyclic aromatic hydrocarbons.
GasificationGasification is a process that converts biomass- or fossil fuel-based carbonaceous materials into gases, including as the largest fractions: nitrogen (N2), carbon monoxide (CO), hydrogen (H2), and carbon dioxide (). This is achieved by reacting the feedstock material at high temperatures (typically >700 °C), without combustion, via controlling the amount of oxygen and/or steam present in the reaction. The resulting gas mixture is called syngas (from synthesis gas) or producer gas and is itself a fuel due to the flammability of the H2 and CO of which the gas is largely composed.
Producer gasProducer gas is fuel gas that is manufactured by blowing through a coke or coal fire with air and steam simultaneously. It mainly consists of carbon monoxide (CO), hydrogen (H2), as well as substantial amounts of nitrogen (N2). The caloric value of the producer gas is low (mainly because of its high nitrogen content), and the technology is obsolete. Improvements over producer gas, also obsolete, include water gas where the solid fuel is treated intermittently with air and steam and, far more efficiently synthesis gas where the solid fuel is replaced with methane.
Dry distillationDry distillation is the heating of solid materials to produce gaseous products (which may condense into liquids or solids). The method may involve pyrolysis or thermolysis, or it may not (for instance, a simple mixture of ice and glass could be separated without breaking any chemical bonds, but organic matter contains a greater diversity of molecules, some of which are likely to break). If there are no chemical changes, just phase changes, it resembles classical distillation, although it will generally need higher temperatures.
TarTar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. Mineral products resembling tar can be produced from fossil hydrocarbons, such as petroleum. Coal tar is produced from coal as a byproduct of coke production. "Tar" and "pitch" can be used interchangeably; asphalt (naturally occurring pitch) may also be called either "mineral tar" or "mineral pitch".
Polycyclic aromatic hydrocarbonA polycyclic aromatic hydrocarbon (PAH) is a class of organic compounds that is composed of multiple aromatic rings. The simplest representative is naphthalene, having two aromatic rings and the three-ring compounds anthracene and phenanthrene. PAHs are uncharged, non-polar and planar. Many are colorless. Many of them are found in coal and in oil deposits, and are also produced by the incomplete combustion of organic matter—for example, in engines and incinerators or when biomass burns in forest fires.
Coal miningCoal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production. In the United Kingdom and South Africa, a coal mine and its structures are a colliery, a coal mine is called a 'pit', and the above-ground structures are a 'pit head'. In Australia, "colliery" generally refers to an underground coal mine.
History of manufactured fuel gasesThe history of gaseous fuel, important for lighting, heating, and cooking purposes throughout most of the 19th century and the first half of the 20th century, began with the development of analytical and pneumatic chemistry in the 18th century. The manufacturing process for "synthetic fuel gases" (also known as "manufactured fuel gas", "manufactured gas" or simply "gas") typically consisted of the gasification of combustible materials, usually coal, but also wood and oil.
Heat of combustionThe heating value (or energy value or calorific value) of a substance, usually a fuel or food (see food energy), is the amount of heat released during the combustion of a specified amount of it. The calorific value is the total energy released as heat when a substance undergoes complete combustion with oxygen under standard conditions. The chemical reaction is typically a hydrocarbon or other organic molecule reacting with oxygen to form carbon dioxide and water and release heat.
FuelA fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy, such as nuclear energy (via nuclear fission and nuclear fusion). The heat energy released by reactions of fuels can be converted into mechanical energy via a heat engine.
AnthraciteAnthracite, also known as hard coal and black coal, is a hard, compact variety of coal that has a submetallic lustre. It has the highest carbon content, the fewest impurities, and the highest energy density of all types of coal and is the highest ranking of coals. Anthracite is the most metamorphosed type of coal (but still represents low-grade metamorphism), in which the carbon content is between 86% and 97%. The term is applied to those varieties of coal which do not give off tarry or other hydrocarbon vapours when heated below their point of ignition.
Wood gas generatorA wood gas generator is a gasification unit which converts timber or charcoal into wood gas, a producer gas consisting of atmospheric nitrogen, carbon monoxide, hydrogen, traces of methane, and other gases, which – after cooling and filtering – can then be used to power an internal combustion engine or for other purposes. Historically wood gas generators were often mounted on vehicles, but present studies and developments concentrate mostly on stationary plants.
Water gasWater gas is a kind of fuel gas, a mixture of carbon monoxide and hydrogen. It is produced by "alternately hot blowing a fuel layer [coke] with air and gasifying it with steam". The caloric yield of this is about 10% of a modern syngas plant. Further making this technology unattractive, its precursor coke is expensive, whereas syngas uses cheaper precursor, mainly methane from natural gas. Synthesis gas is made by passing steam over a red-hot carbon fuel such as coke: (ΔH = +131 kJ/mol) The reaction is endothermic, so the fuel must be continually re-heated to maintain the reaction.
Gas lightingGas lighting is the production of artificial light from combustion of a fuel gas such as hydrogen, methane, carbon monoxide, propane, butane, acetylene, ethylene, coal gas (town gas) or natural gas. The light is produced either directly by the flame, generally by using special mixes (typically propane or butane) of illuminating gas to increase brightness, or indirectly with other components such as the gas mantle or the limelight, with the gas primarily functioning as a heat source for the incandescence of the gas mantle or lime.
Petroleum industryThe petroleum industry, also known as the oil industry or the oil patch, includes the global processes of exploration, extraction, refining, transportation (often by oil tankers and pipelines), and marketing of petroleum products. The largest volume products of the industry are fuel oil and gasoline (petrol). Petroleum is also the raw material for many chemical products, including pharmaceuticals, solvents, fertilizers, pesticides, synthetic fragrances, and plastics.
SyngasSyngas, or synthesis gas, is a mixture of hydrogen and carbon monoxide, in various ratios. The gas often contains some carbon dioxide and methane. It is principally used for producing ammonia or methanol. Syngas is combustible and can be used as a fuel. Historically, it has been used as a replacement for gasoline, when gasoline supply has been limited; for example, wood gas was used to power cars in Europe during WWII (in Germany alone half a million cars were built or rebuilt to run on wood gas).
Coke (fuel)Coke is a grey, hard, and porous coal-based fuel with a high carbon content and few impurities, made by heating coal or oil in the absence of air—a destructive distillation process. It is an important industrial product, used mainly in iron ore smelting, but also as a fuel in stoves and forges when air pollution is a concern. The unqualified term "coke" usually refers to the product derived from low-ash and low-sulphur bituminous coal by a process called coking.
Chemical industryThe chemical industry comprises the companies that develop and produce industrial, specialty and other chemicals. Central to the modern world economy, it converts raw materials (oil, natural gas, air, water, metals, and minerals) into industrial and consumer products. The plastics industry contains some overlap, as some chemical companies produce plastics as well as chemicals. Various professionals are involved in the chemical industry including chemical engineers, chemists and lab technicians.
MethaneMethane (USˈmɛθeɪn , UKˈmiːθeɪn ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes.