With the rapid development of the global economy, steel industry has been developed rapidly. The increasing demand of iron ore at home and abroad further stimulates the development of the benefication of iron ore. As one of the leading enterprises in domestic mineral processing industry, Xinhai has been dedicated commitment to the research and development of iron extraction process and equipment for more than 20 years. According to the magnetic difference of different iron ore,
This iron extraction plant initially used stage grinding – single magnetic separation - fine screening and regrinding process. Xinhai increased cationic reverse flotation process for undersize concentrate. The final concentrate was obtained after one roughing and one cleaning. The reverse flotation froth was sent to regrinding after thickening and magnetic separation, then magnetic concentrate returned to reverse flotation for reprocessing. Finally, iron concentrate was increased from 65.43% to 68.88%.
Xinhai increased anionic reverse flotation process of magnetic concentrate on the basis of the single magnetic separation process. Iron ore concentrate was obtained directly with a roughing, tailings were discarded with three scavenging, middlings returned to efficient thickener. Finally, iron concentrate was increased from 64.25% to 67.22%.
The qualified iron concentrate of this project was obtained with Xinhai round vibrating screen - Xinhai magnetic separator. Oversize middlings were sent to closed-circuit grinding system (including Xinhai wet grid type ball mill and hydrocyclone) for fine grinding. And other qualified concentrates were gained by magnetic separation - fine screen - magnetic separation, then oversize material returned to thickening and magnetic separation for reprocessing. Finally, iron concentrate was increased from 67 % to 69 %, silicon dioxide was reduced from 6.5% to 4.5 %.
Strong magnetic iron ore belongs to free-milling mine, which can get high-grade iron concentrate with weak magnetic separation process. With the improving demand of iron ore concentrate, Xinhai has speeded up the research and innovation of magnetic iron extraction process and magnetic separation equipment in recent years, and achieved remarkable results.
Xinhai increases fine screening-regrinding process in two stage grinding, stage separation, single weak-magnetic separation process, which timely separates fine minerals, reduces the overgrinding and improves the processing capacity of ball mill. The iron concentrate grade increases by about 8%.
Strong adaptability to iron ore. Continuous grinding to monomial dissociation then separate aiming at the fine dissemination size;
The combination of weak magnetic – strong magnetic and anionic reverse flotation not only improves the iron ore grade of anionic reverse flotation, that is easy to obtain high-quality iron concentrate, but also creates good conditions for anionic reverse flotation;
Easy to get good processing index.
Highly targeted process can obtain concentrate and discard tailings. Coarse-grain and fine-grain beneficiation methods not only save cost, but also ensure technical superiority;
Separation of narrow-sized feed avoids the chaos of flotation process and improves the iron extraction efficiency.
Stage grinding reduces two-stage grinding processing capacity;
Preconcentration discarding tailings, tailings quantity generally accounts for more than 45%, which greatly reduces the ore capacity of subsequent work and equipment loss.
On July 14, 2009, Xinhai signed a deal with customers to undertake one-stop mineral processing service about Liaoning Anshan 500t/d iron extraction plant. The project was completed on July 15, 2010 and then put into operation. The final recovery rate was up to 80.5%, estimated annual output of iron ore concentrate was up to 1.8 million tons, the annual turnover reached 30.7 million, 33.8772 million net profit for the year.
No | Task Name | Equipment Name and Specification | Quantity |
---|---|---|---|
1 | Primary and secondary grinding | MQGg 1836 Grid Type Ball Mill | 5*5 |
2 | Primary grinding and classification | 2FLG-2000 Spiral Classifier | 5 |
3 | secondary grinding and classification | 2FLC-1500 Submerged Spiral Classifier | 1 |
4 | Classification before separate | XC II F 200 Hydrocyclone | 3 |
5 | Gravity separation | BLL-2000 Spiral Chute | 27 |
6 | Magnetic separation | CTBy1030 Magnetic Separator CTGG-0814 Magnetic Drum | 8*4 4*2 |
7 | Flotation (Roughing) | SF-8 Flotation Cell | 16 |
8 | Flotation (CleaningⅠ) | JJF-8 Flotation Cell | 7 |
9 | Flotation (CleaningⅡ) | SF-4 Flotation Cell | 5 |
10 | Flotation (CleaningⅢ) | JJF-4 Flotation Cell | 4 |
11 | Dewatering | VD9 High Frequency Dewatering Screen | 8*4 |
12 | Iron concentrate thickening | NZSG-2.5 Efficient Improved Thickener | 2 |
13 | Filtration | PG27-6 Vacuum Filter | 15 |
Liaoning Anshan 500t/d iron extraction plant originally used weak magnetic - strong magnetic opening process. The practice showed that this process failed to select the final qualified iron ore concentrate, and the recovery rate didn’t reach the standard. Therefore, customers specially commissioned Xinhai mineral processing institute to reform. After testing the samples, Xinhai laboratory decided to adopt stage grinding - coarse and fine separation - magnetic separation - gravity separation - anion reverse flotation process. The grinding system consisted of 10 primary ball mill and 4 secondary ball mill. At the same time, Xinhai used fine screening-regrinding technology, which greatly improved iron concentrate grade. After a series of transformation, the iron concentrate grade was up to 72.25%, and the recovery rate was as high as 80.5%.
One stage closed-circuit grinding and classifying system consists of ball mill and cyclone, which not only guarantees the classification efficiency and classification size, but also separates the qualified concentrate in advance.
Magnetic separation timely separates the qualified coarse grain concentrate and tailings. And this combined process reduces more flotation processing quantity and reagents than direct flotation and saves a lot of flotation production cost.
Strong magnetic process recycles fine grained iron ore that plays a role in desliming and tailings discarding. The reverse floatation process has simple reagent system that greatly reduces reagent into the pulp.