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Methanation
Methanation is the conversion of carbon monoxide and carbon dioxide (COx) to methane (CH4) through hydrogenation. The methanation reactions of COx were first discovered by Sabatier and Senderens in 1902. CO''x'' methanation has many practical applications. It is a means of carbon oxide removal from process gases and is also being discussed as an alternative to PROX in fuel processors for mobile fuel cell applications. Methanation as a means of producing synthetic natural gas has been considered since the 1970s. More recently it has been considered as a way to store energy produced from solar or wind power using power-to-gas systems in conjunction with existing natural gas storage. Chemical reactions The following reactions describe the methanation of carbon monoxide and carbon dioxide respectively: :CO + 3H2 -> CH4 + H2O -206 kJ/mol :CO2 + 4H2 -> CH4 + 2 H2O -164 kJ/mol The methanation reactions are classified as exothermic and their energy of formations are listed. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Methanation
Biological methanation (also: microbiological methanation) is a conversion process to generate methane by means of highly specialized microorganisms (Archaea) within a technical system. This process can be applied in a power-to-gas system to produce biomethane and is appreciated as an important storage technology for variable renewable energy in the context of energy transition. This technology was successfully implemented at a first power-to-gas plant of that kind in the year 2015. Disambiguation Biological methanation contains the principle of the so-called methanogenesis, a specific, anaerobic metabolic pathway where hydrogen and carbon dioxide are converted into methane. By analogy with the biological process, a chemical-catalytic process, also known as Sabatier reaction, exists. Principle of function Numerous and common microorganisms within the domain Archaea convert the compounds hydrogen (H2) and carbon dioxide (CO2) into methane in a bio-catalytic way. The therefore re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power-to-gas
Power-to-gas (often abbreviated P2G) is a technology that uses electric power to produce a gaseous fuel. When using surplus power from wind generation, the concept is sometimes called windgas. Most P2G systems use electrolysis to produce hydrogen. The hydrogen can be used directly, or further steps (known as two-stage P2G systems) may convert the hydrogen into syngas, methane, or LPG. Single-stage P2G systems to produce methane also exist, such as reversible solid oxide cell (rSOC) technology. The gas may be used as chemical feedstock, or converted back into electricity using conventional generators such as gas turbines. Power-to-gas allows energy from electricity to be stored and transported in the form of compressed gas, often using existing infrastructure for long-term transport and storage of natural gas. P2G is often considered the most promising technology for seasonal renewable energy storage. Energy storage and transport Power-to-gas systems may be deployed as adjun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sabatier Reaction
The Sabatier reaction or Sabatier process produces methane and water from a reaction of hydrogen with carbon dioxide at elevated temperatures (optimally 300–400 °C) and pressures (perhaps 3 MPa ) in the presence of a nickel catalyst. It was discovered by the French chemists Paul Sabatier and Jean-Baptiste Senderens in 1897. Optionally, ruthenium on alumina (aluminium oxide) makes a more efficient catalyst. It is described by the following exothermic reaction. :CO2 + 4H2 -> atop 400\ ^\circ\ce\ce] CH4 + 2H2O∆''H'' = −165.0 kJ/mol There is disagreement on whether the CO2 methanation occurs by first associatively adsorbing an adatom hydrogen and forming oxygen intermediates before hydrogenation or dissociating and forming a carbonyl before being hydrogenated. : + 3H2 -> + H2O∆''H'' = −206 kJ/mol CO methanation is believed to occur through a dissociative mechanism where the carbon oxygen bond is broken before hydrogenation with an associative mechanism only being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substitute Natural Gas
Substitute natural gas (SNG), or synthetic natural gas, is a fuel gas (predominantly methane, CH4) that can be produced from fossil fuels such as lignite coal, oil shale, or from biofuels (when it is named bio-SNG) or using electricity with power-to-gas systems. SNG in the form of LNG or CNG can be used in road, rail, air and marine transport vehicles as a substitute for costly diesel, petrol, etc. The carbon footprint of SNG derived from coal is comparable to petroleum products. Bio-SNG has a much smaller carbon footprint when compared to petroleum products. LPG can also be produced by synthesising SNG with partial reverse hydrogenation at high pressure and low temperature. LPG is more easily transportable than SNG, more suitable as fuel in two wheeler or smaller HP vehicles /engines and also fetches higher price in international market due to short supply. Renewable electrical energy can also be used to create SNG (methane) via for example electrolysis of water or via a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Renewable Natural Gas
Renewable natural gas (RNG), also known as sustainable natural gas (SNG) or biomethane, is a biogas which has been upgraded to a quality similar to fossil natural gas and having a methane concentration of 90% or greater. By increasing the concentration of methane to a similar level as natural gas, it becomes possible to distribute the gas to customers via the existing gas grid and use in existing appliances. Renewable natural gas is a subset of synthetic natural gas or substitute natural gas (SNG). Multiple ways of methanising carbon dioxide/ monoxide and hydrogen exist, including biomethanation, the Sabatier process and a new electrochemical process pioneered in the United States currently undergoing trials. Advantages Renewable natural gas can be produced and distributed via the existing gas grid, making it an attractive means of supplying existing premises with renewable heat and renewable gas energy, while requiring no extra capital outlay of the customer. The existin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomethane Renewable natural gas (RNG), also known as sustainable natural gas (SNG) or biomethane, is a biogas which has been upgraded to a quality similar to fossil natural gas and having a methane concentration of 90% or greater. By increasing the concentration of methane to a similar level as natural gas, it becomes possible to distribute the gas to customers via the existing gas grid and use in existing appliances. Renewable natural gas is a subset of synthetic natural gas or substitute natural gas (SNG). Multiple ways of methanising carbon dioxide/ monoxide and hydrogen exist, including biomethanation, the Sabatier process and a new electrochemical process pioneered in the United States currently undergoing trials. Advantages Renewable natural gas can be produced and distributed via the existing gas grid, making it an attractive means of supplying existing premises with renewable heat and renewable gas energy, while requiring no extra capital outlay of the c |
