fluidized-bed combustion

fluidized-bed combustion

[¦flü·ə‚dīzd ¦bed kəm′bəs·chən]
(mechanical engineering)
A method of burning particulate fuel, such as coal, in which the amount of air required for combustion far exceeds that found in conventional burners; the fuel particles are continually fed into a bed of mineral ash in the proportions of 1 part fuel to 200 parts ash, while a flow of air passes up through the bed, causing it to act like a turbulent fluid.

Fluidized-bed combustion

A method of burning fuel in which the fuel is continually fed into a bed of reactive or inert material while a flow of air passes up through the bed, causing it to act like a turbulent fluid. Fluidized beds have long been used for the combustion of low-quality, difficult fuels and have become a rapidly developing technology for the clean burning of coal. See Fluidization

A fluidized-bed combustor is a furnace chamber whose floor is slotted, perforated, or fitted with nozzles. Air is forced through the floor and upward through the chamber. The chamber is partially filled with particles of either reactive or inert material, which will fluidize at an appropriate air flow rate. When fluidization takes place, the bed of material expands (bulk density decreases) and exhibits the properties of a liquid. As air velocity increases, the particles mix more violently, and the surface of the bed takes on the appearance of a boiling liquid. If air velocity were increased further, the bed material would be blown away.

Once the bed is fluidized, its temperature can be increased with ignitors until a combustible material can be injected to burn within the bed. Proper selection of air velocity, operating temperature, and bed material will cause the bed to act as a chemical reactor. The three broad areas of application of fluidized-bed combustion are incineration, gasification, and steam generation. See Coal gasification, Combustion, Gas turbine, Steam-generating unit

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studied the fluidized-bed combustion of oil shale retorting residue and found that for semi-coke with a moisture content more than 10%, about 10% of oil shale must be involved to make it burn [4].
Incineration via fluidized-bed combustion is a clean technology which is employed in the treatment of municipal solid waste (RSM) and its main capabilities are volume reduction and the possibility of energy recovery.
International contributors in computer, electronics, and systems engineering explore areas such as artificial neural networks in solar thermal energy systems, the application of control algorithms for wind speed prediction and active power generation, learning control of fluidized-bed combustion processes for power plants, and the application of computational intelligence techniques to architectural and building acoustics.
Researchers applied a form of flyash gleaned from a coal-burning process called fluidized-bed combustion that is employed by the electric utility industry.
Such systems include fluidized-bed combustion, biomass-integrated gasification, and biomass externally fired gas turbines.
The good news is that new technologies have been introduced in recent years to combat the environmental problems posed by coal consumption, including fluidized-bed combustion and limestone injection.
US engineers Cheremisinoff and Rezaiyan have worked for many years respectively in clean technologies for manufacturing and energy production, and in fluidized-bed combustion and gasification technology development.
Integrated gasification combined-cycle (IGCC) and pressurized fluidized-bed combustion (PFBC) are two examples of types of new-generation advanced coal-fired power plants.
Sulfur in the coal reacts with calcium from the limestone, forming gypsum and calcium oxide in a process called fluidized-bed combustion (FBC).
Of the dozen or more advanced technologies under development, two of the more promising are fluidized-bed combustion and coal gasification.
For application in integrated burning technologies based on circulating fluidized-bed combustion (CFBC) fired with a mixture fuel of fine oil shale and spent shale (shale char), the second zone would be practically favorable since fine shale retorting at temperatures below 550[degrees]C would produce spent shale possessing good combustion properties in terms of fixed carbon and residual organics [18].