Where does the dust in the air come from?

Dust comes from industrial emissions, combustion smoke and dust, soil dust, etc.

Principles of production:

1, mechanical processing or crushing of solid substances, such as metal grinding, cutting, drilling, blasting, crushing, grinding, processing of agricultural and forestry products, etc.

2. Materials are heated in air, such as dust particles formed by steam condensation or oxidation when metals are melted, welded and cast.

3. Particles formed by incomplete combustion of organic substances, such as smoke and dust generated when wood, oil and coal are burned.

4. Dust is suspended in the air again (secondary dust is generated) during casting operations such as sand turning, sand cleaning, screening, packaging and handling, and dust deposited due to vibration or airflow movement is also the source of dust.

Extended data:

Dust can be roughly divided into two types according to particle size:

A speck of dust

Dust is a kind of dust produced by the breaking of objects and diffused into the air.

Second, condense solid smoke.

Condensed solid smoke is formed in the process of combustion, sublimation, evaporation and condensation. Its particle size is generally 0. 1 μm ~ 1 μm, which is different from dust and has great cohesion. Most of them are gases formed during the melting process of metal substances. After cooling in air, it condenses into solid smoke, and the particle shape is more regular.

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