Cradle to Gate
Identity ID
3fe3d5e7-f9f2-442d-b314-ebe501cc8979
Materials
Associated ID
d7910fee-8eb7-4c1b-ac0f-10490aa12940
Included activities starts
Included activities ends
Description
This dataset represents the comprehensive beneficiation technology for lean magnetite in China, processing magnetite. It covers the full life cycle inventory (cradle-to-gate) from crushing to the production of hematite concentrate, encompassing all activities related to iron concentrate beneficiation production, but excluding direct or indirect greenhouse gas emissions from the production of crushing equipment, magnetic separation equipment, personnel travel during the beneficiation process, and daily office operations. The dataset was compiled from multiple data sources based on Chinese national standards such as the 'Manual of Production and Emission Coefficients for the Iron Ore Mining and Processing Industry (0810)', 'Emission standard of pollutants for mining and mineral procressing industry (GB 28661-2012)', 'Cleaning production standard Iron ore mining and mineral processing industry', and 'The norm of the energy consumption per unit product of iron ore dressing(GB31337-2014)'. It represents the average production level of magnetite processing using integrated beneficiation technologies in China's lean magnetite ore sector.
Activity Description
This dataset describes a comprehensive beneficiation technology for low-grade magnetite, with the following process flow:
1. Multi-stage Dry Pre-selection
Process Description: After primary crushing, medium crushing, and fine crushing, the ore enters a magnetic pulley pre-selection system for multi-stage dry pre-selection. The purpose of pre-selection is to remove most of the non-magnetic waste rock through the magnetic pulley system, thereby increasing the ore grade. This stage of dry pre-selection allows for the early separation of a large amount of waste rock, reducing the workload of subsequent grinding and beneficiation processes.
Results: This step can effectively increase the grade of the ore entering the grinding mill, typically increasing the iron grade by 5%~10%, reducing grinding energy consumption, and improving the efficiency of subsequent processing.
2. More Crushing, Less Grinding
Process Description: After pre-selection, the ore enters a multi-stage crushing system for progressive fine crushing, reducing the material load on subsequent grinding processes. Using crushing to replace part of the grinding reduces the amount of material entering the grinding equipment, lowers grinding energy consumption, and simultaneously improves the liberation degree of mineral particles.
Effects: This multi-crushing, multi-grinding process significantly reduces grinding energy consumption while improving ore liberation, providing high-quality feedstock for subsequent beneficiation processes.
3. Stage Magnetic Separation and Tailings Disposal
Process Description: The ore after multi-crushing and multi-grinding enters a magnetic separator for staged magnetic separation. The magnetic separator separates iron minerals from gangue minerals. Magnetic iron minerals are adsorbed by the magnetic separator drum, while non-magnetic gangue is discarded as tailings. The magnetic separation process is carried out in multiple stages. In each stage, the proportion of waste rock in the tailings increases, and the grade of iron concentrate gradually improves.
Effects: Through staged magnetic separation, the grade of iron concentrate can be further improved, while a large amount of low-grade tailings is discarded, reducing the load on subsequent processing.
4. Fine Screening-Magnetic Agglomeration Upgrading
Fine Screening and Classification: After magnetic separation, the slurry is screened through fine screening equipment. Qualified minerals after screening enter the cleaning stage, while unqualified coarse particles are returned to the regrinding system for secondary or tertiary grinding to ensure the degree of mineral particle liberation.
Magnetic Agglomeration Upgrading: Fine-grained minerals that have passed screening enter the magnetic agglomeration system. Magnetic agglomeration technology utilizes the adsorption between magnetic particles to aggregate fine magnetic iron minerals into larger agglomerates, thereby improving the magnetic separation effect. Through magnetic agglomeration, the enrichment degree of mineral particles increases, the impurity content decreases, and the final concentrate grade is improved.
Results: The fine screening-magnetic agglomeration process can increase the iron concentrate grade to 66.8% while significantly reducing the gangue mineral content.
5. Magnetic Scavenging in Tailings
Process Description: After stage magnetic separation, the tailings still contain a small amount of magnetic iron minerals. Through the magnetic scavenging process in the tailings, the residual iron minerals in the tailings are recovered and re-enter the beneficiation system for processing. The magnetic scavenging equipment can further screen the tailings, recovering insufficiently liberated iron minerals, thereby reducing iron mineral waste.
Results: Magnetic scavenging can increase the metal recovery rate to 69%, significantly reducing iron loss in the tailings and improving the overall utilization rate of mine resources.
6. High-Efficiency and Energy-Saving Tailings Treatment and Concentrate Recovery
Ceramic Filter: The refined iron concentrate is dehydrated using a ceramic filter, reducing its moisture content (typically below 10%) and improving its transportability. Ceramic filters are highly efficient and energy-saving, reducing energy consumption while decreasing moisture content, thus improving production efficiency.
Tailings Treatment: Tailings are transported to a tailings dam or dry-discharged via a tailings conveyor system. Highly efficient tailings treatment equipment reduces harmful substances in the tailings, ensuring that tailings emissions meet environmental protection requirements and achieving clean production goals.
Process Description
In this dataset, the iron concentrate has a grade of 66.8% and belongs to transition metals, being the primary product of the mineral beneficiation process. Iron concentrate is typically in powder form and is widely used in downstream processing at sintering and pelletizing plants, serving as a key raw material in steel production.
Time period
2022
2026
Geography
China
Geography comment
Forming China's average data through merging multiple provincial datasets
Macroeconomic value
Business-as-Usual
Data validation
Yes
Technology
Current Technology
Technology comment
Integrated beneficiation technology for lean magnetite. Technical principle: The integrated beneficiation technology for lean magnetite refers to a complete set of comprehensive utilization technology characterized by "multi-stage dry pre-selection, more crushing and less grinding, staged magnetic separation and tailings rejection, fine screening, magnetic agglomeration for quality improvement, and medium-intensity magnetic cleaning of tailings." In the crushing system, multi-stage magnetic pulleys are used for pre-selection and waste rejection, thereby enhancing the grinding feed grade and system processing capacity. Advanced technological processes and equipment are employed to improve the quality of crushed products, achieve more crushing and less grinding, and reduce energy consumption. Staged magnetic separation with tailings rejection ensures sufficient liberation of valuable minerals from gangue minerals, increasing both production and product quality. The "fine screening-magnetic agglomeration" technique is adopted to effectively separate intergrown particles, reduce impurities, and upgrade the final product quality. Improving the grade of iron concentrate; adopting magnetic cleaning technology in tailings to enhance metal recovery rate and reduce iron loss; applying high-efficiency, energy-saving ceramic filtration and tailings transportation technology to achieve clean production. Technical applicability and characteristics: This technology increases metal recovery rate and reduces pollution at the source. Implementing this technology can achieve an iron concentrate grade of 66.8% and an iron recovery rate of 69%. This technology is suitable for lean magnetite ores.