With a Mohs hardness of 1–3, bauxite is the most important aluminum ore containing 30%–60% aluminum oxide. Industrially, Bayer process is commonly used to extract alumina.
Bauxite grinding is a crucial step in alumina production. The grinding process and equipment directly impact the extraction efficiency of Bayer process.
Uses of bauxite powder
Bauxite powder, rich in alumina, is widely used in metallurgy, refractories, building materials, chemicals, ceramics and environmental protection, demonstrating broad economic value.
Bauxite powders of varying fineness are used in different ways across industries.
| Fineness | Uses of bauxite powders |
| Coarse powder (80–200 mesh) | High-alumina cement raw material; general refractory materials |
| Medium-fine powder (200–325 mesh) | High-quality refractory castable; cement clinker additives |
| Fine powder (325–800 mesh) | Ceramic industry; fine refractory products |
| Ultrafine powder (800–3,000 mesh) | High-quality ceramics; composite materials; abrasives |
The bauxite powder grinding process
A complete bauxite powder grinding process consists of crushing, grinding, and collection. The key stage is grinding to produce qualified bauxite powder.
- Crushing: Large bauxite ores are fed through a vibrating feeder into a jaw crusher for initial crushing and an impact crusher for secondary crushing.
- Grinding: The material in the silo is evenly conveyed to the grinding mill. It can be ground to varying fineness based on requirements, generally between 80 and 600 mesh.
- Collection: The powder selector can separate and send qualified bauxite powder to the collector. And the pulse dust collector can remove dust from gases to meet emission standard.
Through scientific bauxite grinding process, it can achieve higher uses and ensure the purity of bauxite powder. It also has low dust emissions and energy consumption.
3 types of bauxite grinding machines
The main goal of grinding is to produce fine bauxite powder with suitable fineness for smelting or further processing. The grinding machine directly determines its fineness, capacity, and quality.
Common bauxite grinding equipments:
- Ball mill
- Vertical grinding mill
- Raymond mill
1. Bauxite ball mill Get a quote
Grinding powder can be used in Bayer process to produce alumina. Our popular ball mills are capable of wet grinding bauxite.
Wet ball mill can operate continuously for the long time, with a production capacity of up to 615 t/h, making them suitable for large-scale bauxite grinding plants.
Bauxite wet ball mill offers the following advantages:
- Grind bauxite with high moisture content (8%–12%).
- Produce bauxite slurry with a fineness of 80%–85% below 200 mesh, suitable for slurrying process.
- Enclosed system, low noise, minimal dust, and environmentally friendly.
- FTM Machinery offers a sufficient parts supply, minimizing maintenance time.
Our best-selling bauxite ball mill models:
| Model | Capacity(t/h) | Feeding size(mm) | Discharge size |
| Φ1830×4500 | 4.5–12 | ＜25 | Below 200 mesh, fineness accounts for 80%–85% |
| Φ2700×4500 | 26–90 | ＜25 | Below 200 mesh, fineness accounts for 80%–85% |
2. Bauxite vertical grinding mill Get a quote
Vertical grinding mill can integrate grinding, classification, and drying for dry grinding of bauxite.
With hydraulic pressure to boost grinding force, bauxite vertical grinding mill can achieve up to 420 t/h output, ideal for large-scale production.
Our FTM Machinery's vertical grinding mill offers the advantages over traditional grinding machines:
- It can process bauxite with 15% humidity. Direct contact with internal hot air reduces finished bauxite powder moisture to ≤1%.
- With a dynamic classifier, the efficiency can be up to 97%, producing 0.37–0.84 mm high-quality bauxite powder.
- It is a vertical structure with minimal space for bauxite grinding and easy to operate. The investment is 70% lower than a ball mill system.
- It operates under full negative pressure with a dust collector capturing 99.9% and no leakage. Energy consumption is 35% lower than ball mill.
- Made of wear-resistant cast steel, grinding rollers and table have a long life.
Our best-selling bauxite vertical grinding mill models:
| Model | Capacity(t/h) | Feeding size(mm) | Discharge size |
| HLM1500K | 13–50 | ≤20 | 0.37–0.84 mm (20-400 mesh) |
| HLM2800K | 50–200 | ≤20 | 0.37–0.84 mm (20-400 mesh) |
3. Bauxite Raymond mill Get a quote
Our FTM Machinery's Raymond mills have helped local grinding plants achieve efficient and stable production in Europe, Africa, Southeast Asia and other places.
With the feed size ≤30 mm, the bauxite powder grinding equipment produces with a fineness of 0.044–0.173 mm and a capacity of 1–22 t/h.
Raymond mill offers the following advantages for bauxite grinding:
- Dust removal rates up to 99%, resulting in high-purity bauxite powder, enabling dust recovery and eco-friendly production.
- Bauxite Raymond mill offers low price and investment cost.
- Flexible control of bauxite powder fineness to meet diverse production needs.
- Suitable for small and medium-sized bauxite powder grinding, high productivity and energy-saving.
- With an integral gearbox and anti-vibration system, it can last over 30 years.
Our best-selling bauxite Raymond mill models:
| Model | Capacity(t/shift) | Feeding size(mm) | Discharge size |
| 4525 | 16–176 | ≤30 | 0.044–0.173 mm (80–325 mesh) |
| 4119 | 8–78 | ≤30 | 0.044–0.173 mm (80–325 mesh) |
Customer case: Vertical grinding machine for sale in Malaysia
A Malaysian alumina plant built a new bauxite grinding line. It uses bauxite with about 8% moisture and needs 50 t/h of bauxite powder with 200–400 mesh and finally chose a vertical grinding mill.
Operational results:
- Bauxite powder fineness remains stable at 400 mesh, with a production capacity of 50 t/h.
- The moisture content of bauxite powder is controlled ≤1% with high quality.
- Automated control ensures continuous production with high efficiency.
- The clean system removes 99% of dust, keeping dust emissions well below local environmental standards.
Customer comment:
"FTM Machinery's vertical grinding machine ensures a stable supply of bauxite powder for our plant's production line and improves alumina extraction efficiency. It also increases profitability."
