Fly ash

from Wikipedia, the free encyclopedia

As airborne dust is dust referred arising from industrial processes and with either exhaust gas is discharged or remains in the waste gas cleaning devices. The term fly ash is mainly used in connection with combustion processes or metallurgical processes. In older publications the term is also used synonymously for dust precipitation . Dust -like adsorbents used for exhaust gas cleaning are also referred to as fly ash.

Origin and composition

Flue dusts arise, among other things, in incineration processes, for example in the incineration of waste or in the production of Portland cement clinker, or in metallurgical processes, such as the extraction of lead . Accordingly, they can have high organic proportions or be of an inorganic nature. Due to their properties as condensation nuclei , flue dusts can contain numerous inorganic and organic substances.

meaning

Airborne dusts can lead to health problems as, among other things, polychlorinated dibenzodioxins and dibenzofurans can be bound to them.

Airborne dust can cause technical problems in exhaust ducts. For example, flue dust can lead to caking that has to be cleaned off regularly. Airborne dust deposited on the heating surfaces of air preheaters can lead to glowing pockets.

In metallurgical processes, flue dust is often returned to the production process. For example, fly ash generated in the manufacture of lead and lead alloys can be used for secondary lead extraction.

Since flue dusts also serve as condensation nuclei , measures for dedusting the exhaust gas are often also effective exhaust gas cleaning measures .

Individual evidence

  1. ^ E. Effenberger: Airborne dust measurements. In: dust . 19, No. 10, 1959, pp. 373-374.
  2. ↑ VDI 3891: 2015-07 emission reduction; Systems for human cremation (emission control; human cremation facilities). Beuth Verlag, Berlin, p. 29.
  3. ↑ VDI 3928: 2017-01 Waste gas cleaning by chemisorption. Beuth Verlag, Berlin, p. 48.
  4. ↑ Julia Vogel, Volker Weiss, Jürgen Oischinger, Robert Daschner, Martin Meiller: Treatment of waste containing nanomaterials in thermal waste treatment plants. In: Hazardous substances - cleanliness. Air . 76, No. 9, 2016, ISSN  0949-8036 , pp. 331-337.
  5. ↑ Klaus Kersting, Uwe Musanke, Reinhold Rühl: DNEL values ​​in the construction industry. In: Hazardous substances - cleanliness. Air. 72, No. 3, 2012, ISSN  0949-8036 , pp. 109-113.
  6. ↑ VDI 2597: 2004-07 emission reduction; Plants for the production of lead and lead alloys. Beuth Verlag, Berlin, p. 12.
  7. ↑ VDI 3462 sheet 4: 2009-03 emission reduction; Woodworking and processing; Burning wood and wood-based materials without wood preservatives, without organic halogenated coatings and without coatings containing heavy metals (Emission control; Wood machining and processing; Combustion of wood and wood-based panels not treated with wood preservatives and not coated with materials containing halogenated organic compounds and heavy metals). Beuth Verlag, Berlin, p. 29.
  8. ↑ VDI 3790 sheet 1: 2015-07 environmental meteorology ; Emissions of gases, odors and dusts from diffuse sources; Basics (Environmental meteorology; Emissions of gases, odors and dusts from diffuse sources; Fundamentals). Beuth Verlag, Berlin, p. 16.
  9. ↑ VDI 2102 sheet 1: 2007-12 emission reduction; Secondary copper smelting and refining plants. Beuth Verlag, Berlin, p. 4.
  10. ↑ VDI 3460 sheet 1 : 2014-02 emission reduction; Thermal waste treatment; Basics (Emission control; Thermal waste treatment; Fundamentals). Beuth Verlag, Berlin. P. 67.
  11. ↑ VDI 3930: 1998-05 exhaust gas cooling and heating. Beuth Verlag, Berlin, p. 44.
  12. ↑ VDI 2597: 2004-07 emission reduction; Plants for the production of lead and lead alloys. Beuth Verlag, Berlin, p. 30.
  13. ↑ VDI 3927 sheet 2: 2015-05 exhaust gas cleaning; Reduction of inorganic and organic trace substances in waste gases from combustion processes (flue gases) (Waste gas cleaning; Reduction of inorganic and organic trace species in combustion flue gases). Beuth Verlag, Berlin. P. 19.