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Removal, conversion and utilization technologies of alkali components in bayer red mud.
Shanliang Ma1, Xiaoming Liu2, Zengqi Zhang1
1School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Journal of Environmental Management
|December 22, 2024
Summary
This study examines Bayer red mud, an alkaline waste from alumina production. It reviews methods to reduce alkalinity and explores alkali utilization in recycling, cement, and environmental applications.
Area of Science:
- Environmental Science
- Materials Science
- Industrial Chemistry
Background:
- Bayer red mud poses environmental risks due to its high alkalinity, hindering its utilization.
- Alkalinity is regulated by soluble free alkali and chemically bound alkali in red mud.
Purpose of the Study:
- To analyze alkaline components in red mud.
- To review dealkalization technologies and alkali utilization strategies.
- To identify research barriers and future directions for red mud management.
Main Methods:
- Systematic analysis of red mud composition and alkaline components.
- Comprehensive review of dealkalization technologies (acid, CO2 neutralization, salt precipitation).
- Evaluation of alkali in-situ conversion and utilization in cement clinker, hydration, and geopolymers.
Main Results:
- Current dealkalization methods have limitations.
- Alkali components play a beneficial role in red mud recycling and applications.
- Red mud shows potential in acid wastewater neutralization and flue gas desulfurization.
Conclusions:
- Effective management of red mud alkalinity is crucial for its sustainable utilization.
- Further research is needed to overcome technical barriers in alkali regulation and application.
- In-situ alkali conversion offers promising avenues for red mud recycling.
Keywords:
Bayer red mudCementitious materialsChemically bound alkaliDealkalizationSoluble free alkaliMore Related Videos
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