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Pulverizer
A pulverizer or grinder is a mechanical device for the grinding of many different types of materials. For example, a pulverizer mill is used to pulverize coal for combustion in the steam-generating furnaces of coal power plants. Types of coal pulverizers Coal pulverizers may be classified by speed, as follows:Coal Pulverising Mill Types, by Glenn Schumacher, 2010 * Low Speed * Medium Speed * High Speed Low speed Ball and tube mills A ball mill is a pulverizer that consists of a horizontal rotating cylinder, up to three diameters in length, containing a charge of tumbling or cascading steel balls, pebbles, or rods. A tube mill is a revolving cylinder of up to five diameters in length used for fine pulverization of ore, rock, and other such materials; the material, mixed with water, is fed into the chamber from one end, and passes out the other end as a slurry. Both types of mill include liners that protect the cylindrical structure of the mill from wear. Thus the main wear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulverized Coal-fired Boiler
A pulverized coal-fired boiler is an industrial or utility boiler that generates thermal energy by burning pulverized coal (also known as powdered coal or coal dust since it is as fine as face powder in cosmetic makeup) that is blown into the firebox. The basic idea of a firing system using pulverised fuel is to use the whole volume of the furnace for the combustion of solid fuels. Coal is ground to the size of a fine grain, mixed with air and burned in the flue gas flow. Biomass and other materials can also be added to the mixture. Coal contains mineral matter which is converted to ash during combustion. The ash is removed as bottom ash and fly ash. The bottom ash is removed at the furnace bottom. This type of boiler dominates coal-fired power stations, providing steam to drive large turbines. History Prior to the developments leading to the use of pulverized coal, most boilers utilized grate firing where the fuel was mechanically distributed onto a moving grate at the bottom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Power Plant
A thermal power station is a type of power station in which heat energy is converted to electrical energy. In a steam-generating cycle heat is used to boil water in a large pressure vessel to produce high-pressure steam, which drives a steam turbine connected to an electrical generator. The low-pressure exhaust from the turbine enters a steam condenser where it is cooled to produce hot condensate which is recycled to the heating process to generate more high pressure steam. This is known as a Rankine cycle. The design of thermal power stations depends on the intended energy source: fossil fuel, nuclear and geothermal power, solar energy, biofuels, and waste incineration are all used. Certain thermal power stations are also designed to produce heat for industrial purposes; for district heating; or desalination of water, in addition to generating electrical power. Fuels such as natural gas or oil can also be burnt directly in gas turbines (internal combustion). These plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal-fired 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 Nameplate capacity, capacity. They generate about a third of the Electric energy consumption, 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 Pulverizer, 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 electric generator, 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 gigatonne, Gt of carbon dioxide each year, about one fifth of world greenhouse gas emissions, so are the single largest Attribution of re ... [...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 prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slurry
A slurry is a mixture of denser solids suspended in liquid, usually water. The most common use of slurry is as a means of transporting solids or separating minerals, the liquid being a carrier that is pumped on a device such as a centrifugal pump. The size of solid particles may vary from 1 micrometre up to hundreds of millimetres. The particles may settle below a certain transport velocity and the mixture can behave like a Newtonian or non-Newtonian fluid. Depending on the mixture, the slurry may be abrasive and/or corrosive. Examples Examples of slurries include: *Cement slurry, a mixture of cement, water, and assorted dry and liquid additives used in the petroleum and other industries *Soil/cement slurry, also called Controlled Low-Strength Material (CLSM), flowable fill, controlled density fill, flowable mortar, plastic soil-cement, K-Krete, and other names *A mixture of thickening agent, oxidizers, and water used to form a gel explosive *A mixture of pyroclastic materi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Bearing
A thrust bearing is a particular type of rotary bearing. Like other bearings they permanently rotate between parts, but they are designed to support a predominantly axial load. Thrust bearings come in several varieties. *''Thrust ball bearings'', composed of bearing balls supported in a ring, can be used in low thrust applications where there is little axial load. *''Cylindrical thrust roller bearing''s consist of small cylindrical rollers arranged flat with their axes pointing to the axis of the bearing. They give very good carrying capacity and are cheap, but tend to wear due to the differences in radial speed and friction which is higher than with ball bearings. *'' Tapered roller thrust bearings'' consist of small tapered rollers arranged so that their axes all converge at a point on the axis of the bearing. The length of the roller and the diameter of the wide and the narrow ends and the angle of rollers need to be carefully calculated to provide the correct taper so that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . The longest human chromosome, chromosome 1, is approximately in length. Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Predictive Maintenance
Predictive maintenance techniques are designed to help determine the condition of in-service equipment in order to estimate when maintenance should be performed. This approach promises cost savings over routine or time-based preventive maintenance, because tasks are performed only when warranted. Thus, it is regarded as condition-based maintenance carried out as suggested by estimations of the degradation state of an item. The main promise of predictive maintenance is to allow convenient scheduling of corrective maintenance, and to prevent unexpected equipment failures. The key is "the right infor equipment lifetime, increased plant safety, fewer accidents with negative impact on environment, and optimized spare parts handling. Predictive maintenance differs from preventive maintenance because it relies on the actual condition of equipment, rather than average or expected life statistics, to predict when maintenance will be required. Typically, Machine Learning approaches are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schwarze Pumpe Power Station
Schwarze Pumpe power station (german: Kraftwerk Schwarze Pumpe translated: ''Black Pump Power Station'') is a modern lignite (brown coal)–fired power station in the "Schwarze Pumpe" (Black Pump) district in Spremberg, Germany consisting of 2 × 800 megawatts (MW) units. The current plant came into service in 1997–1998 and was built by Siemens. The power station was sold by Vattenfall to the Czech energy group EPH and its financial partner PPF Investments on 30September 2016. The cooling towers are high and have an observation deck on top. The site has been a large-scale industrial site processing lignite since the DDR period, when it was first developed (since 1955). The DDR-era plant used the lignite to produce high temperature lignite coke for blast furnaces, coal gas to fire steam turbine electrical generation, motor fuels, and a variety of chemical feedstocks. Carbon capture and storage pilot plant Construction started on 26 May 2006, in the Schwarze Pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mill (grinding)
A mill is a device, often a structure, machine or kitchen appliance, that breaks solid materials into smaller pieces by grinding, crushing, or cutting. Such comminution is an important unit operation in many processes. There are many different types of mills and many types of materials processed in them. Historically mills were powered by hand or by animals (e.g., via a hand crank), working animal (e.g., horse mill), wind ( windmill) or water ( watermill). In modern era, they are usually powered by electricity. The grinding of solid materials occurs through mechanical forces that break up the structure by overcoming the interior bonding forces. After the grinding the state of the solid is changed: the grain size, the grain size disposition and the grain shape. Milling also refers to the process of breaking down, separating, sizing, or classifying aggregate material (e.g. mining ore). For instance rock crushing or grinding to produce uniform aggregate size for construction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burr Mill
A burr mill, or burr grinder, is a mill used to grind hard, small food products between two revolving abrasive surfaces separated by a distance usually set by the user. When the two surfaces are set far apart, the resulting ground material is coarser, and when the two surfaces are set closer together, the resulting ground material is finer and smaller. Often, the device includes a revolving screw that pushes the food through. It may be powered electrically or manually. Burr mills do not heat the ground product by friction as much as blade grinders ("choppers"), and produce particles of a uniform size determined by the separation between the grinding surfaces. Food burr mills are usually manufactured for a single purpose: coffee beans, dried peppercorns, coarse salt, spices, or poppy seeds, for example. Coffee mills for volume consumption are usually powered by electric motors, but fast and precise manual mills have experienced an uptick in popularity in the 2020s for individual- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cement Mill
A cement mill (or finish mill in North American usage) is the equipment used to grind the hard, nodular clinker from the cement kiln into the fine grey powder that is cement. Most cement is currently ground in ball mills and also vertical roller mills which are more effective than ball mills. History Early hydraulic cements, such as those of James Parker, James Frost and Joseph Aspdin were relatively soft and readily ground by the primitive technology of the day, using flat millstones. The emergence of Portland cement in the 1840s made grinding considerably more difficult, because the clinker produced by the kiln is often as hard as the millstone material. Because of this, cement continued to be ground very coarsely (typically 20% over 100 μm particle diameter) until better grinding technology became available. Besides producing un-reactive cement with slow strength growth, this exacerbated the problem of unsoundness. This late, disruptive expansion is caused by hydratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
