Cradle to Gate
Identity ID
705bd12f-09bd-4de3-acb3-1b47462771c8
Materials
Associated ID
cb6a31b5-bed3-4c48-aa02-bbe7f76cf2f1
Included activities starts
Included activities ends
Description
This dataset represents iron ore from underground mining in Liaoning. It covers the life cycle inventory (cradle-to-gate) from rock drilling to iron ore production, including all activities related to iron ore mining and production, but excluding the direct or indirect greenhouse gas emissions from the production of drilling rigs, transportation equipment, personnel commuting, and daily office operations during the mining production process. The dataset was compiled from multiple data sources based on 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)', representing the average production level of iron ore mined by shrinkage stoping in Liaoning.
Activity Description
This dataset describes the iron ore mining in Liaoning using the shallow-hole shrinkage stoping method. The process flow is as follows:
1. Orebody exploration and borehole layout design
Orebody exploration: Prior to mining, detailed geological exploration of the orebody is conducted to determine its shape, size, dip angle, and mineral composition. Based on this information, mining design is carried out.
Borehole layout design: According to the shape of the orebody and the thickness of the ore layer, a reasonable shallow-hole layout plan is designed. The depth of the shallow holes is typically several meters to a dozen meters, and the hole spacing and row spacing are determined based on the stability of the orebody and the mining method. During the borehole layout design, the degree of ore liberation and blasting efficiency must also be considered.
2. Drilling and Blasting
Drilling operation: Shallow holes are drilled into the ore body according to the blasthole layout design. Drilling machines typically use handheld or lightweight equipment, offering flexibility and suitability for working in narrow underground mine drifts. The drill hole diameter usually ranges from 50 mm to 100 mm.
Charging and blasting: Explosives are loaded into the drilled holes according to the characteristics of the ore body and the hole design, followed by blasting. The shallow hole blasting technique effectively controls ore fracturing and detachment, minimizing excessive damage to the ore structure. After each blast, the broken ore is recovered by gravity or mechanical means. Ore Extraction
Staged Extraction: Ore extraction is typically carried out in multiple stages. After each blasting section, workers recover the broken ore, usually loading it into trucks or conveying systems via mechanical or manual shoveling equipment for transportation out of the mine.
Pillar Retention: During the extraction process, certain portions of ore are left in place as pillars to support the overlying orebody and surrounding rock, preventing mine collapse. These pillars are retained temporarily and are extracted in the final stage. The layout and extraction timing of the pillars are crucial for stope stability. Pillar recovery
Pillar recovery: After most of the ore in the upper part of the orebody has been extracted, the recovery of pillars is carried out. At this time, smaller blasting forces may be used to detach and collapse the pillars, ensuring the stability of the underground structure.
Support and reinforcement: After pillar recovery, the mine structure may become unstable, requiring reinforcement. Common support methods include rock bolting and shotcreting.
5. Ore Transportation and Haulage
Transport System: In shrinkage stoping, ore transportation typically employs small-scale mechanical equipment (e.g., load-haul-dump machines, belt conveyors) to move ore to the shaft hoisting point. Depending on the geological conditions and mine design, the ore can be transported to the surface via rail cars, belt conveyors, or inclined shaft hoisting systems.
Surface Processing: After the ore is hoisted to the surface, it is sent to the mineral processing plant for crushing, grinding, and beneficiation.
Process Description
Iron ore is the primary raw material for steel production, and steel is one of the core materials for modern industry and infrastructure. China is the world's largest steel producer and has enormous demand for iron ore. However, China's iron ore resources are characterized by low grade and high impurity content, requiring most iron ore to undergo beneficiation before use. Magnetic separation is the main beneficiation technology for iron ore in China, especially suitable for magnetite and vanadium-titanium magnetite. For non-magnetic or weakly magnetic ores such as hematite, limonite, and siderite, a combination of processes including roasting, gravity separation, high-intensity magnetic separation, and flotation is typically required to improve the yield and grade of iron concentrate.
Time period
2022
2026
Geography
China,Liaoning
Geography comment
Forming Liaoning's average data through merging data from multiple sources
Macroeconomic value
Business-as-Usual
Data validation
Yes
Technology
Current Technology
Technology comment
Shallow-hole shrinkage stoping is a mining method commonly used for underground iron ore mining, particularly suitable for orebodies with small thickness and steep dip angles. The main characteristics of this method include staged shallow-hole blasting and ore extraction, combined with support from ore pillars and surrounding rock, to reduce subsidence and surface impact.