Charring is a chemical process of incomplete combustion Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame. Fuels of interest often include organic compounds in the gas, liquid or of a solid when subjected to high heat In physics and thermodynamics, heat is the process of energy transfer from one body or system due to thermal contact, which in turn is defined as an energy transfer to a body in any other way than due to work performed on the body. The resulting residue matter is called Char Char is the solid material that remains after light gases and tar (e.g. coal tar) have been driven-out or released from a carbonaceous material, during the initial stage of combustion, which is known as carbonization, charring, devolatilization or pyrolysis. Further stages of efficient combustion (with or without char deposits) are known as. Charring can be either a deliberate and controlled reaction used in manufacturing or it may be the result of naturally-occurring processes. By the action of heat, charring removes hydrogen Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an atomic weight of 1.00794 u, hydrogen is the lightest and most abundant chemical element, constituting roughly 75 % of the Universe's elemental mass. Stars in the main sequence are mainly composed of hydrogen in its plasma state. Naturally occurring and oxygen Oxygen , from the Greek roots ὀξύς (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter), is the element with atomic number 8 and represented by the symbol O. It is a member of the chalcogen group on the periodic table, and is a highly reactive nonmetallic period 2 element that from the solid, so that the remaining char is composed primarily of carbon Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, with 12C and 13C being stable, while 14C is radioactive, decaying with a half-life of. It often occurs to biological tissue Tissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues (living or dead) and organic compounds like wood or thermosetting polymers.
The mechanism of charring is part of normal combustion of solids. During normal combustion the volatile compounds created by charring are consumed as the visible flames within the fire, while combustion of char is seen as glowing red coals or embers which burn without the presence of flames.
Production of Char
Coke Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous and charcoal Charcoal is the black residue consisting of impure carbon obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood, sugar, bone char, or other substances in the absence of oxygen . The resulting soft, brittle, lightweight, black, porous are both produced by charring, whether on an industrial scale or through normal combustion of coal or wood. Normal combustion consumes the char as well as the gases produced in its creation, while industrial processes seek to recover the purified char with minimal loss to combustion. This is accomplished by either burning the parent fuel (wood or coal) in a low-oxygen environment or by heating it to a high temperature without allowing combustion to occur. In industrial production of coke and charcoal the volatile compounds driven off during charring are often captured for use in other chemical processes.
A "coal burning" blacksmith's A blacksmith is a person who creates objects from iron or steel by forging the metal; i.e., by using tools to hammer, bend, and cut. Blacksmiths produce things like wrought iron gates, grills, railings, light fixtures, furniture, sculpture, tools, agricultural implements, decorative and religious items, cooking utensils, horseshoes and weapons forge The basic smithy contains a forge, also known as a hearth, for heating metals. The forge heats the workpiece to a malleable temperature or to the point where work hardening no longer occurs. The workpiece is transported to and from the forge using tongs. The tongs are also used to hold the workpiece on the smithy's anvil while the smith works it actually produces the heat necessary for high-temperature metalworking Metalworking is the process of working with metals to create individual parts, assemblies, or large scale structures. The term covers a wide range of work from large ships and bridges to precise engine parts and delicate jewellery. It therefore includes a correspondingly wide range of skills, processes, and tools by the continuous production and consumption of coke within a carefully managed fire. An inner ring of burning coke provides heat which converts the encircling coal into coke, which is then itself fed into the center of the fire to provide the required heat and to create more coke; coal itself is incapable of producing the heat required for some blacksmithing operations.
Charring and fire protection
Charring is an important process in the combustion ignition of solid fuels Fuel is any material that is burned or altered to obtain energy and to heat or to move objects. Fuel releases its energy either through a chemical reaction means, such as combustion, or nuclear means, such as nuclear fission or nuclear fusion. An important property of a useful fuel is that its energy can be stored to be released only when needed, and in smouldering Smouldering is the slow, low-temperature, flameless form of combustion, sustained by the heat evolved when oxygen directly attacks the surface of a condensed-phase fuel . Many solid materials can sustain a smouldering reaction, including coal, cellulose, wood, cotton, tobacco, peat, duff, humus, synthetic foams, charring polymers including. In construction of heavy-timbered wood buildings the predictable formation of char is used to determine the fire rating of supporting timbers and is an important consideration in fire protection Fire protection is the study and practice of mitigating the unwanted effects of fires. It involves the study of the behaviour, compartmentalisation, suppression and investigation of fire and its related emergencies, as well as the research and development, production, testing and application of mitigating systems. In structures, be they land-based, engineering. If a wood column is of large enough diameter, during a structure fire its exposed surface will be converted to char until the thickness of char provides sufficient insulation to prevent additional charring. This layer then serves to protect the remaining structurally sound core of wood, which can continue to carry the building loads if appropriately designed.
Legal definitions
Charring had a special meaning under the common law Common law is law developed by judges through decisions of courts and similar tribunals , rather than through legislative statutes or executive branch action. A "common law system" is a legal system that gives great precedential weight to common law, on the principle that it is unfair to treat similar facts differently on different of England England ( /ˈɪŋɡlənd/ ) is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west and the North Sea to the east, with the English Channel to the south separating it from continental Europe. Most of England. Under that system, the crime of arson Arson is the crime of intentionally and maliciously setting fire to structures or wildland areas. It may be distinguished from other causes such as spontaneous combustion and natural wildfires. The study of the causes is the subject of fire investigation. Arson usually describes fires deliberately set to the property of another or to one's own required charring of a dwelling—actual damage to the fiber of the material from which the structure was built—and not mere "scorching" or damage to the surface, or to surface coverings such as carpets and wallpaper.
Categories: Chemical processes Categories: Chemical engineering | Chemistry | Industrial processes | Process chemicals | Coal Categories: Fossil fuels | Economic geology | Sedimentary rocks | Granular materials | Organic minerals |
(muse_sprite)
2008-07-17 15:23:20
muse_sprite posted a photo:. london~. charring. cross hotel. stairway.
