Study on the proportion of paste filling materials based on fluorogypsum

Area of Science:

• Materials Science
• Geotechnical Engineering
• Environmental Science

Background:

• The high cost of traditional paste filling materials presents a significant challenge in mining operations.
• Industrial waste, such as fluorogypsum and coal gangue, requires effective disposal and utilization strategies.

Purpose of the Study:

• To develop a cost-effective paste filling material using fluorogypsum as a primary raw material.
• To investigate the influence of key components (gangue, fly ash, fluorogypsum, lime) and mass concentration on material properties.
• To evaluate the feasibility of the developed material for consolidating loose rock strata and filling goaf.

Main Methods:

• Formulation optimization by varying proportions of coal gangue, fly ash, fluorogypsum, and lime.
• Assessment of physical properties including slump and extension.
• Characterization of mineral composition and microstructure using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM).
• Mechanical testing to determine compressive strength at 28 days.

Main Results:

• The optimal mix comprised 1000g coal gangue, 300g fly ash, 300g fluorogypsum, and 50g lime at a 78% mass concentration.
• The developed paste filling material achieved a compressive strength of 4-5MPa at 28 days.
• XRD and SEM analyses identified ettringite, calcium sulfate dihydrate, and calcium silicate hydrate gel as hydration products.

Conclusions:

• The novel fluorogypsum-based paste filling material is a viable, cost-effective alternative for mine filling applications.
• This approach effectively addresses the disposal challenges of industrial wastes like fluorogypsum and coal gangue.
• The material contributes to ecological environment management by repurposing waste products.