“fluidization”的概念、定义、翻译、参考文献-科学参考

fluidization

Physics

A technique used in some industrial processes in which solid particles suspended in a stream of gas are treated as if they were in the liquid state. Fluidization is useful for transporting powders, such as coal dust. Fluidized beds, in which solid particles are suspended in an upward stream, are extensively used in the chemical industry, particularly in catalytic reactions where the powdered catalyst has a high surface area. They are also used in furnaces, being formed by burning coal in a hot turbulent bed of sand or ash through which air is passed. The bed behaves like a fluid, enabling the combustion temperature to be reduced so that the production of polluting oxides of nitrogen is diminished. By adding limestone to the bed with the fuel, the emission of sulphur dioxide is reduced.

High-pressure fluidized beds are also used in power-station furnaces in a combined cycle in which the products of combustion from the fluidized bed are used to drive a gas turbine, while a steam-tube boiler in the fluid bed raises steam to drive a steam turbine. This system both increases the efficiency of the combustion process and reduces pollution.

Chemistry

A technique used in some industrial processes in which solid particles suspended in a stream of gas are treated as if they were in the liquid state. Fluidization is useful for transporting powders, such as coal dust. Fluidized beds, in which solid particles are suspended in an upward stream, are extensively used in the chemical industry, particularly in catalytic reactions where the powdered catalyst has a high surface area. They are also used in furnaces, being formed by burning coal in a hot turbulent bed of sand or ash through which air is passed. The bed behaves like a fluid, enabling the combustion temperature to be reduced so that the production of polluting oxides of nitrogen is diminished. By adding limestone to the bed with the fuel, the emission of sulphur dioxide is reduced.
High-pressure fluidized beds are also used in power-station furnaces in a combined cycle in which the products of combustion from the fluidized bed are used to drive a gas turbine, while a steam-tube boiler in the fluid bed raises steam to drive a steam turbine. This system both increases the efficiency of the combustion process and reduces pollution.

Chemical Engineering

The process of suspending solid particles in an upward flow of a fluid and is widely used to promote good heat transfer and mass transfer in fluidized beds. In particulate fluidization involving liquids, each particle behaves individually and collides with others remaining a certain distance apart. As the velocity of fluidization is increased, the bed expands. It is used in backwashing of filter beds and ion exchange resin beds. In aggregated fluidization involving gases, similar conditions exist up to the point of incipient fluidization. At higher velocities, flow passes through the bed in the form of bubbles and the bed expands due to the volume of the bubbles.

Geology and Earth Sciences

Process of passing gas through loose, fine-grained particles causing the mixture to flow like a liquid; this facilitates mixing and chemical reaction. The faster the gas flows the more the mixture expands and movement increases. A bubble phase may form which travels upwards until all the solid particles are transported by the gas. Fluidization is used in coal-fired power stations and may occur naturally in volcanic eruptions producing pyroclastic flows and surges. It is the phenomenon which enables pyroclastic flows to travel distances in excess of 100 km and to surmount topographic obstacles hundreds of metres high.

单词	fluidization
释义	fluidization Physics A technique used in some industrial processes in which solid particles suspended in a stream of gas are treated as if they were in the liquid state. Fluidization is useful for transporting powders, such as coal dust. Fluidized beds, in which solid particles are suspended in an upward stream, are extensively used in the chemical industry, particularly in catalytic reactions where the powdered catalyst has a high surface area. They are also used in furnaces, being formed by burning coal in a hot turbulent bed of sand or ash through which air is passed. The bed behaves like a fluid, enabling the combustion temperature to be reduced so that the production of polluting oxides of nitrogen is diminished. By adding limestone to the bed with the fuel, the emission of sulphur dioxide is reduced. High-pressure fluidized beds are also used in power-station furnaces in a combined cycle in which the products of combustion from the fluidized bed are used to drive a gas turbine, while a steam-tube boiler in the fluid bed raises steam to drive a steam turbine. This system both increases the efficiency of the combustion process and reduces pollution. Chemistry A technique used in some industrial processes in which solid particles suspended in a stream of gas are treated as if they were in the liquid state. Fluidization is useful for transporting powders, such as coal dust. Fluidized beds, in which solid particles are suspended in an upward stream, are extensively used in the chemical industry, particularly in catalytic reactions where the powdered catalyst has a high surface area. They are also used in furnaces, being formed by burning coal in a hot turbulent bed of sand or ash through which air is passed. The bed behaves like a fluid, enabling the combustion temperature to be reduced so that the production of polluting oxides of nitrogen is diminished. By adding limestone to the bed with the fuel, the emission of sulphur dioxide is reduced. High-pressure fluidized beds are also used in power-station furnaces in a combined cycle in which the products of combustion from the fluidized bed are used to drive a gas turbine, while a steam-tube boiler in the fluid bed raises steam to drive a steam turbine. This system both increases the efficiency of the combustion process and reduces pollution. Chemical Engineering The process of suspending solid particles in an upward flow of a fluid and is widely used to promote good heat transfer and mass transfer in fluidized beds. In particulate fluidization involving liquids, each particle behaves individually and collides with others remaining a certain distance apart. As the velocity of fluidization is increased, the bed expands. It is used in backwashing of filter beds and ion exchange resin beds. In aggregated fluidization involving gases, similar conditions exist up to the point of incipient fluidization. At higher velocities, flow passes through the bed in the form of bubbles and the bed expands due to the volume of the bubbles. Geology and Earth Sciences Process of passing gas through loose, fine-grained particles causing the mixture to flow like a liquid; this facilitates mixing and chemical reaction. The faster the gas flows the more the mixture expands and movement increases. A bubble phase may form which travels upwards until all the solid particles are transported by the gas. Fluidization is used in coal-fired power stations and may occur naturally in volcanic eruptions producing pyroclastic flows and surges. It is the phenomenon which enables pyroclastic flows to travel distances in excess of 100 km and to surmount topographic obstacles hundreds of metres high.
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