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[Spatial Distribution Characteristics and Graded Utilization Path of Coal Gangue in China]
Xin-Ru Cui1, Xue-Ping Huo2, Bing-Jie Zhou2
1Institute of Resources and Environment Engineering, Shanxi University, Taiyuan 030006, China.
Huan Jing Ke Xue= Huanjing Kexue
|April 15, 2025
Summary
China
Area of Science:
- Waste Management
- Environmental Science
- Materials Science
Context:
- China generates 600-800 million tons of coal gangue annually, with cumulative storage reaching 60-70 billion tons.
- Regional variations in coal gangue properties due to lithology and mineral composition are often overlooked.
- Existing utilization rates are around 70%, with significant potential for increase.
Purpose:
- To analyze the current utilization status and potential of coal gangue.
- To propose a regionalized grading and utilization scheme considering industrial policies, spatial heterogeneity, and technological potential.
- To address the limitations posed by regional heterogeneity in coal gangue research and utilization.
Summary:
- Analysis reveals a shift from power generation and building materials to eco-friendly disposal like underground filling and land reclamation.
- Comprehensive utilization increased from 61.9% to 72.2% in the last decade, driven by filling disposal.
- Eco-friendly disposal is identified as the primary growth area for nationwide coal gangue utilization.
Impact:
- A regionalized utilization scheme is proposed, prioritizing filling disposal in high-production areas like Shanxi, Shaanxi, and Inner Mongolia.
- Specific recommendations include alumina extraction from Inner Mongolia's gangue, power generation from Shanxi's high-calorific value gangue, and local building material use in eastern regions.
- "Coal-for-gangue" substitution and underground filling technology development are highlighted for Shandong and Hebei.
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