Custom Concrete Northern was involved in the development of paste backfill technology with Inco in 1987 and started our first paste operation at Kinross mines in 1995. This operation took tailings directly from the cake filter to backfill. Since then we have installed additional Paste plants in various mines across Northern Ontario are supplying the daily paste requirements for mining operations.
What is Paste Backfill?
Paste Backfill is used to safely provide ground support in most underground mining operations. As mines mill down extracted ore from underground and separate out the precious metals they are left with a product called “tailings.” These tailings are often stored in man-made dams or ponds to properly separate them from the environment. Mine tailings are hauled from dams or ponds to our Pastefill plant where a binder, called Portland cement is added to achieve the desired mix. This unique blend is then shipped back underground and used to fill voids of extracted material to increase the structural integrity of mining operations; while also improving environmental conditions for present mining operations. Depending on the anatomic and rheological requirements of the paste other materials like sand or a combination of both may be used.
How Does it Work?
Paste backfill is used in underground hard rock mines primarily to fill the vertical stopes where veins of precious metals are extracted. Rheology, the study of deformation and flow of matter is crucial to ensure the product reaches its destination thousands of meters underground. To do so, small pipes are directed throughout the underground mine accessing the necessary location to deliver the product.
Strength of the material is just as crucial, supporting not only the ground and equipment that travels along the surface of the stopes but also the pillars and walls. The benefits extend beyond that of the mines operations by mitigating the risks associated with tailings storage and reducing the remediation costs.
Why Custom Concrete Northern?
Since being established in Northern Ontario, Custom Concrete Northern has been handling materials and operating batching plants in some of the most extreme conditions found in Canada. Having similar operations throughout our product lines means we have the manpower and scale to start up new projects and immediately run 24 hours a day, 7 days a week, year round. Each project is different, no two mines have the same materials and every plant requires something unique in their design. Our 20+ years’ experience in performing past fill production and designing of facilities give us the expertise to custom design and produce paste for any application. This includes the material science component as well as facility design and operation.