Industrial dedusting is the process of removing solid particles (dust) from exhaust gases from industrial plants and from the air in production halls. The aim is to protect the health of employees, the environment and machinery and equipment from the consequences of dust pollution. In some industries, the recovery of dust represents an additional economic advantage.
The dedusting process usually includes:
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Dust transport – Suction and transportation of dust-laden air through a duct system to the dust extraction systems.
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Dust separation from the gas – separation of solid particles using physical mechanisms (gravitation, centrifugal force, filtration, electrostatics, wet separation).
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Discharge of purified gas – emission into the atmosphere according to standards or internal recirculation.
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Collection and recovery of dust – Collection in containers, recycling or disposal.
Main dust collection technologies:
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Gravity separators (settling chambers)
Use the slowing down of the gas flow so that heavier particles sink. Mainly used for the pre-separation of large dust fractions.
Advantages: simple design, low cost.
Disadvantages: low efficiency with fine particles.
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Bag filter / fabric filter
The air flows through a porous fabric on which the dust is deposited and forms a filter layer.
Advantages: very high efficiency (over 99%), remove particles from 0.1 µm.
Disadvantages: require regular maintenance and replacement of the bags, sensitive to moisture.
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Electrostatic precipitators
High voltage causes ionization of the particles, which are attracted to the collecting electrodes.
Advantages: high efficiency even with the finest dusts, low flow resistance.
Disadvantages: high investment costs, large space requirement.
System selection
The choice of technology depends on the properties of the dust, the gas parameters, the required efficiency, the costs and the available space. In practice, multi-stage systems that combine different methods (e.g. cyclone + bag filter) are often used to achieve optimum efficiency and operating costs.
