[PAH removal from black sludge from aluminium industry by flotation using non-ionic surfactants]

Environ Technol. 2006 Sep;27(9):1019-30. doi: 10.1080/09593332708618716.
[Article in French]

Abstract

The valorization of black sludge is an environmental problem of the aluminium industry because of Polycyclic Aromatic Hydrocarbon (PAH), fluoride and alumina contents. A soil washing operated in a cell flotation with non-ionic surfactants (Brij 35, Igepal CA-720, Triton X-100, Tween 80) at different concentrations has been tested in order to remove the PAH (benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)fluoranthene, fluoranthene) detected in black sludge. The Tween 80 at 0.5% gave the best results with PAH removal rates between 35 and 50%. These percentages remain low due to the presence in large quantity of fine solid particles (45%) in the PAH concentrate produced by the flotation process. The substitution of the cell flotation by a column flotation allowed the reduction of this problem. Thus, the PAH removal rates reached 60%. This removal yield has been obtained with the lowest wash water flow-rate (150 ml min(-1)) and pulp total solids (10% p p(-1)) tested.

MeSH terms

  • Aluminum / chemistry*
  • Industrial Waste*
  • Polycyclic Aromatic Hydrocarbons / chemistry*
  • Sewage / chemistry*
  • Surface-Active Agents / chemistry*
  • Waste Management / methods

Substances

  • Industrial Waste
  • Polycyclic Aromatic Hydrocarbons
  • Sewage
  • Surface-Active Agents
  • Aluminum