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Co-firing
{{No footnotes, date=November 2010 Co-firing is the combustion of two (or more) different types of materials at the same time. One of the advantages of co-firing is that an existing plant can be used to burn a new fuel, which may be cheaper or more environmentally friendly. For example, biomass is sometimes co-fired in existing coal plants instead of new biomass plants. Another example is that biomass primary fuel fractions can be cofired with waste-derived fuels in biomass plants leading to an environmentally friendly destruction of waste fractions and cost-effective heat and power production. Co-firing can also be used to improve the combustion of fuels with low energy content. For example, landfill gas contains a large amount of carbon dioxide, which is non-combustible. If the landfill gas is burned without removing the carbon dioxide, the equipment may not perform properly or emissions of pollutants may increase. Co-firing it with natural gas increases the heat content of the fue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomass
Biomass is plant-based material used as a fuel for heat or electricity production. It can be in the form of wood, wood residues, energy crops, agricultural residues, and waste from industry, farms, and households. Some people use the terms biomass and biofuel interchangeably, while others consider biofuel to be a ''liquid'' or ''gaseous'' fuel used for transportation, as defined by government authorities in the US and EU. The European Union's Joint Research Centre defines solid biofuel as raw or processed organic matter of biological origin used for energy, such as firewood, wood chips, and wood pellets. In 2019, biomass was used to produce 57 EJ (exajoules) of energy, compared to 190 EJ from crude oil, 168 EJ from coal, 144 EJ from natural gas, 30 EJ from nuclear, 15 EJ from hydro and 13 EJ from wind, solar and geothermal combined. Approximately 86% of modern bioenergy is used for heating applications, with 9% used for transport and 5% for electricity. Most of the global b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Power Station
A coal-fired power station or coal power plant is a thermal power station which burns coal to generate electricity. Worldwide, there are about 8,500 coal-fired power stations totaling over 2,000 gigawatts capacity. They generate about a third of the world's electricity, but cause many illnesses and early deaths, mainly from air pollution. A coal-fired power station is a type of fossil fuel power station. The coal is usually pulverized and then burned in a pulverized coal-fired boiler. The furnace heat converts boiler water to steam, which is then used to spin turbines that turn generators. Thus chemical energy stored in coal is converted successively into thermal energy, mechanical energy and, finally, electrical energy. Coal-fired power stations emit over 10 Gt of carbon dioxide each year, about one fifth of world greenhouse gas emissions, so are the single largest cause of climate change. More than half of all the coal-fired electricity in the world is generated in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion Gas
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A sim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retrofitting
Retrofitting is the addition of new technology or features to older systems. Retrofits can happen for a number of reasons, for example with big capital expenditures like naval vessels, military equipment or manufacturing plants, businesses or governments may retrofit in order to reduce the need to replace a system entirely. Other retrofits may be due to changing codes or requirements, such as seismic retrofit which are designed strengthening older buildings in order to make them earthquake-resistant. Retrofitting is also an important part of climate change mitigation and climate change adaptation: because society invested in built infrastructure, housing and other systems before the magnitude of changes anticipated by climate change. Retrofits to increase building efficiency, for example, both help reduce the overall negative impacts of climate change by reducing building emissions and environmental impacts while also allowing the building to be more healthy during extreme wea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stoves
A stove or range is a device that burns fuel or uses electricity to generate heat inside or on top of the apparatus, to be used for general warming or cooking. It has evolved highly over time, with cast-iron and induction versions being developed. Stoves can be powered with many fuels, such as electricity, gasoline, wood, and coal. Due to concerns about air pollution, efforts have been made to improve stove design. Pellet stoves are a type of clean-burning stove. Air-tight stoves are another type that burn the wood more completely and therefore, reduce the amount of the combustion by-products. Another method of reducing air pollution is through the addition of a device to clean the exhaust gas, for example, a filter or afterburner. Research and development on safer and less emission releasing stoves is continuously evolving. Etymology The term "stove" is derived from the Old English word ''stofa'', indicating any individual enclosed space or room; "stove" may sometimes still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blast Furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being "forced" or supplied above atmospheric pressure. In a blast furnace, fuel ( coke), ores, and flux (limestone) are continuously supplied through the top of the furnace, while a hot blast of air (sometimes with oxygen enrichment) is blown into the lower section of the furnace through a series of pipes called tuyeres, so that the chemical reactions take place throughout the furnace as the material falls downward. The end products are usually molten metal and slag phases tapped from the bottom, and waste gases (flue gas) exiting from the top of the furnace. The downward flow of the ore along with the flux in contact with an upflow of hot, carbon monoxide-rich combustion gases is a countercurrent exchange and chemical reaction process. In contrast, air furnaces (such as reverbera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valorization Of Waste
Waste valorization, beneficial reuse, value recovery or waste reclamation is the process of waste products or residues from an economic process being valorized (given economic value), by reuse or recycling in order to create economically useful materials. The term comes from practices in sustainable manufacturing and economics, industrial ecology and waste management. The term is usually applied in industrial processes where residue from creating or processing one good is used as a raw material or energy feedstock for another industrial process. Industrial wastes in particular are good candidates for valorization because they tend to be more consistent and predictable than other waste, such as household waste. Historically, most industrial processes treated waste products as something to be disposed of, causing industrial pollution unless handled properly. However, increased regulation of residual materials and socioeconomic changes, such as the introduction of ideas about sustain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cement Kilns
A cement is a binder, a chemical substance used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel (aggregate) together. Cement mixed with fine aggregate produces mortar for masonry, or with sand and gravel, produces concrete. Concrete is the most widely used material in existence and is behind only water as the planet's most-consumed resource. Cements used in construction are usually inorganic, often lime or calcium silicate based, which can be characterized as hydraulic or the less common non-hydraulic, depending on the ability of the cement to set in the presence of water (see hydraulic and non-hydraulic lime plaster). Hydraulic cements (e.g., Portland cement) set and become adhesive through a chemical reaction between the dry ingredients and water. The chemical reaction results in mineral hydrates that are not very water-soluble and so are quite durable in water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grate Firing
Grate firing is a type of industrial combustion system used for solid fuels. It now is used mainly for burning waste and biomass, but also for smaller coal Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dea ... furnaces. * Capacities 0.3 to 175 MWth in industry and CHP * Fuel fired per grate area 1-2 MW/m2, maximum grate area 100 m2 * Grates are typical only suitable for coarse particles, for fine particles a spreader is required, increases max. capacity * Primary air through the grate (also used for cooling) and secondary air Types ;Travelling grate :A moving grate which is covered with a fuel layer, 10-30 cm. Power control by means of varying the grate velocity ;Reciprocating grate :For ash-rich, low calorific fuels like municipal waste, arrangement of stationary and moving grates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluidized Bed Combustion
Fluidized bed combustion (FBC) is a combustion technology used to burn solid fuels. In its most basic form, fuel particles are suspended in a hot, bubbling fluidity bed of ash and other particulate materials (sand, limestone etc.) through which jets of air are blown to provide the oxygen required for combustion or gasification. The resultant fast and intimate mixing of gas and solids promotes rapid heat transfer and chemical reactions within the bed. FBC plants are capable of burning a variety of low-grade solid fuels, including most types of coal, coal waste and woody biomass, at high efficiency and without the necessity for expensive fuel preparation (e.g., pulverising). In addition, for any given thermal duty, FBCs are smaller than the equivalent conventional furnace, so may offer significant advantages over the latter in terms of cost and flexibility. FBC reduces the amount of sulfur emitted in the form of SO''x'' emissions. Limestone is used to precipitate out sulfate du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
