Title:
乾式吸着により気体状媒体から物質を分離する方法
Document Type and Number:
Japanese Patent JP3859706
Kind Code:
B2
Abstract:
PCT No. PCT/SE95/01392 Sec. 371 Date Jun. 9, 1997 Sec. 102(e) Date Jun. 9, 1997 PCT Filed Nov. 22, 1995 PCT Pub. No. WO96/15846 PCT Pub. Date May 30, 1996The treatment, through a dry adsorption process, of a gas from a hot electrolytic process for aluminum production comprises at least two stages. Particulate aluminum oxide (the adsorbent) passes through the stages of the adsorption process countercurrently to the gas. Thus, the gas is treated with a partly spent adsorbent in a first dry adsorption stage, whereupon the particulate adsorbent is separated from the gas downstream from the first adsorption stage. Part of the separated particulate adsorbent is removed from the adsorption process for recycling adsorbed fluorine-containing substances to the electrolytic process. The remainder of the separated adsorbent is recirculated in the first adsorption stage in order to optimize the adsorption of fluorine-containing substances and the desorption of sulfur dioxide from the aluminum oxide in this stage. Simultaneously, the gas is transferred to a second dry adsorption stage. In this second stage, the gas is treated with essentially unspent, reactive particulate aluminum oxide, so that any gaseous fluoride remaining in the gas is very efficiently adsorbed, while at the same time a substantial part of the sulfur dioxide in the gas is also adsorbed. Finally, this particulate aluminum oxide is separated from the gas downstream from the second dry adsorption stage, before the gas is discharged into the surrounding atmosphere. The separated aluminum oxide is transferred to the first adsorption stage, optionally after passing a desorption stage for the removal of the adsorbed sulfur dioxide in order to reduce the discharges of sulfur dioxide from the aluminum production. The separation of sulphur dioxide in the second adsorption stage is improved by recycling, to the second adsorption stage, aluminum oxide having undergone the desorption treatment.
Inventors:
Vierne, Odd E.
Wedee, Gale
Wedee, Gale
Application Number:
JP51678296A
Publication Date:
December 20, 2006
Filing Date:
November 22, 1995
Export Citation:
Assignee:
Alstom, power, holding, actie borrag
International Classes:
B01D53/08; C25C3/06; B01D53/10; B01D53/12; B01D53/68; B01D53/83; C01B7/20; C25C3/22; C01B7/19
Domestic Patent References:
| JP50108194A | ||||
| JP58074505A |
Attorney, Agent or Firm:
Kenji Yoshitake
Yukitaka Nakamura
Konno Akio
Noritaka Yokota
Masaharu Takamura
Yukitaka Nakamura
Konno Akio
Noritaka Yokota
Masaharu Takamura