Enabling sustainable mining to lower the environmental impact.
The mining industry, which includes hard rock, coal, and open pit operations, requires chemical solutions to increase efficiency and profitability while improving safety. Construction solutions are provided for tunneling and mining, including solutions for pre-injection, rock bolting, injection, and sprayed concrete.
Backfill involves placing material into the underground voids created by mining. This process is crucial due to trends toward deeper excavation and optimizing the extraction sequence. Backfill operations are a significant cost factor, representing 25 to 30 per cent of the overall mining costs.
| Challenges/Goals of Backfilling | How Admixtures Help (Benefits) | Types of Admixtures Used |
|---|---|---|
| Cost Reduction & Efficiency | Optimizing the backfill process can significantly reduce overall operational costs. Benefits include savings on binders and water, increased production rates, lower maintenance costs, and improved productivity and placement of the fill. | Common admixtures include water reducers, superplasticizers, viscosity modifiers, rheology enhancers, and hydration control solutions. Powder-form admixtures can improve workability, durability, and overall performance of the backfill material. |
| Performance and Stability | Ensures the right balance between early strength and long-term durability while maintaining dimensional stability after placement. Deeper excavations increase geotechnical challenges and stresses. | Admixtures can improve dimensional stability, reduce the risk of fill failure or liquefaction, and promote rapid strength development. Specialized accelerators and sprayed concrete additives are often used in high-stress applications. |
| Logistics and Operations | Backfilling involves the blending of binders, water, and aggregates, often over long distances. Continuous and flexible placement is essential for operational efficiency. | Rheology-controlling admixtures improve pumpability, reduce viscosity issues, and minimize blockage risks, enhancing productivity during placement. |
A major trend in modern mining is the reduction of environmental impact. Admixtures play a role in promoting a 'Total Mining Cycle - Sustainable Approach'. Sustainable benefits specifically achieved through backfilling technologies and concrete admixtures include: