Device and a method of cleaning an effluent gas from an aluminium production electrolytic cell

Patent metadata

Field	Value
Publication number	US-2016101384-A1
Application number	US-201514969734-A
Country	US
Kind code	A1
Filing date	Dec 15, 2015
Priority date	Feb 18, 2011
Publication date	Apr 14, 2016
Grant date	—

Abstract

A gas cleaning unit for cleaning an effluent gas of at least one aluminium production electrolytic cell comprises a contact reactor in which the effluent gas is brought into contact with alumina, and a dust removal device for removing at least a portion of the alumina. The gas cleaning unit further comprises a wet scrubber in which the effluent gas is brought into contact with an absorption liquid containing water for removing further pollutants from the effluent gas. The wet scrubber is positioned at a point vertically higher than that of the dust removal device.

First claim

1 . A method of cleaning an effluent gas of at least one aluminium production electrolytic cell comprising:
providing a gas cleaning unit comprising
at least one contact reactor configured such that the effluent gas is contactable with alumina,
a dust removal device configured such that at least a portion of the alumina having adsorbed pollutants from the effluent gas in the contact reactor is separable from the effluent gas, and
a wet scrubber configured such that effluent gas flowing from the dust removal device is contactable with an absorption liquid containing water for removing further pollutants from the effluent gas, the wet scrubber being positioned at a point vertically higher than that of the dust removal device;
contacting effluent gas with alumina adsorbing at least a portion of the content of pollutants of the effluent gas in the contact reactor; separating at least a portion of adsorbed pollutants from the effluent gas using the dust removal device; and contacting the effluent gas with an absorption liquid comprising water in the wet scrubber to further remove pollutants from the effluent gas.

2 . The method according to claim 1 , further comprising effluent gas from which at least a portion of the adsorbed pollutants has been separated by the dust removal device flowing into a clean gas plenum arranged at a top of the dust removal device, and flowing further horizontally out of the clean gas plenum with a vertically upward flow into the wet scrubber.

3 . The method according to claim 1 , wherein flowing of effluent gas into the wet scrubber comprises effluent gas flowing vertically upward into a housing of the wet scrubber via a bottom of the wet scrubber housing.

4 . The method according to claim 1 , wherein the effluent gas flows vertically upward when passing from the contact reactor to the dust removal device and wherein the effluent gas flows vertically upward when flowing from the dust removal device to the wet scrubber.

Assignees

• Alstom Technology Ltd

Inventors

• Bjarno Odd Edgar
• Wedde Geir

Classifications

• B01D53/10 Primary

  with dispersed adsorbents · CPC title

• B01D2252/60

  Additives · CPC title

• C25C3/22

  Collecting emitted gases · CPC title

• B01D53/1437

  Pretreatment by adsorption · CPC title

• B01D53/685

  by treating the gases with solids · CPC title