What kiln is used to burn bauxite: full analysis of production process and equipment selection
Bauxite (also known as bauxite) is an important raw material for the production of alumina and metallic aluminum. Its calcination process directly affects product quality and energy consumption. This article will systematically analyze the selection of bauxite calcination equipment based on the hot topics on the Internet in the past 10 days, and attach a comparison of the latest industry data.
1. Comparison of bauxite calcining kiln types
| Kiln type | Applicable scale | temperature range | Thermal efficiency | Latest technological improvements |
|---|---|---|---|---|
| Rotary kiln | Large (100,000-500,000 tons/year) | 1200-1500℃ | 55-65% | New sealing structure reduces energy consumption by 15% |
| vertical kiln | Small and medium-sized (50,000-200,000 tons/year) | 900-1300℃ | 60-70% | Intelligent temperature control system improves uniformity |
| tunnel kiln | Specialty products production | 800-1200℃ | 50-60% | Waste heat recovery device saves energy by 30% |
| Suspension roaster | New test line | 700-1000℃ | 75-85% | Low NOx combustion technology |
2. Industry hot technology trends in 2024
1.Wave of energy-saving renovation:Recently, many companies have released energy-saving plans for kilns. For example, a company in Shandong reduced the coal consumption of rotary kilns by 1.2kg/t through preheater modification.
2.Intelligent control:A project in Henan uses an AI temperature prediction system to improve the calcination uniformity by 18%, which has become the focus of the industry.
3.Impact of new environmental protection regulations:The Ministry of Ecology and Environment's latest "Emission Standards for Air Pollutants from Industrial Furnaces" has triggered heated discussions, requiring NOx emissions to be ≤150mg/m³.
3. Analysis of key factors in kiln type selection
| Considerations | Rotary kiln | vertical kiln | Suspension furnace |
|---|---|---|---|
| investment cost | High (about 120 million/piece) | Medium (60-80 million) | Highest (200 million+) |
| operating costs | 0.18-0.22 yuan/kg | 0.15-0.18 yuan/kg | 0.12-0.15 yuan/kg |
| Product adaptability | Broad spectrum applicable | Low to medium grade ore | Requires preprocessing |
| Environmental performance | Requires matching dust removal | Easy to control dust | best |
4. Latest developments of typical enterprises
1.Chinalco Group:In June, it was announced that the world's first intelligent suspension roasting production line would be put into operation in Guangxi, with a designed production capacity of 300,000 tons/year.
2.Nanshan Aluminum:Completed the digital transformation of the old rotary kiln, implemented remote monitoring and energy efficiency analysis, and topped the industry hot search list.
3.International news:Alcoa released a new low-energy-consumption rotary kiln technology patent, triggering domestic technology follow-up discussions.
5. Operation suggestions
1.Large enterprises:Priority is given to rotary kilns with waste heat power generation systems, which have the best overall benefits.
2.Small and medium enterprises:Modular vertical kiln groups can be selected to flexibly respond to market changes.
3.New project:It is recommended to evaluate suspension roasting technology. Although the initial investment is large, it is in line with the long-term low-carbon trend.
Conclusion:With the advancement of the dual-carbon goal, bauxite calcination equipment is facing a critical period of technology iteration. Enterprises need to choose the most suitable kiln type plan based on their own scale, raw material characteristics and environmental protection requirements. The latest data shows that kilns using intelligent control systems will account for 73% of new projects in 2024, and technological upgrading is imperative.
check the details
check the details
en
