Industry

Emission Control Materials for Alumina Plants

Emission problems, pollutants, operating conditions and recommended materials for the alumina sector.

Typical emission problems

  • NOx from calcination
  • High dust with alumina fines
  • CO from roasting off-gas on some lines

Main pollutants

  • NOx
  • Dust
  • CO

Operating conditions

Alumina calcination exhaust is dusty with fine particulates. Plate-type SCR catalysts with high open area are commonly applied.

Recommended material selection

  • Plate-type SCR DeNOx catalyst for dusty flue gas
  • Combined CO oxidation + SCR sequence where roasting off-gas carries CO

Engineering considerations

Alumina calcination and roasting lines emit NOx in high-temperature process gas with a dust that is abrasive and chemically reactive. The SCR system must sit at a point in the process where the temperature is inside the catalyst window and the dust has been largely removed.

Because alumina plants often operate continuously with limited outage windows, catalyst layer management follows the same principle as power plants: a spare layer position, planned layer replacement and pressure drop monitoring to catch plugging early.

Where CO is also present — roasting off-gas can carry significant CO — a combined CO oxidation + SCR sequence is evaluated on the actual gas data before design.

Tell us about your stream

Gas flow, concentration, temperature, humidity, SO₂ and dust — we will recommend the right catalyst or adsorbent system.