Engineering the tail end of tailings
My job is never boring. I have been traveling around the world for a year, visiting mining sites in Latin America, Australia and Africa and of course here in Ireland to discover what makes each of them tick and find the most efficient ways to bring optimal yield and minimal waste. When it comes to tailings dams, I have seen the good, the bad and the ugly. So much has been written about the viability of dams and the dangers associated to their sheer existence, but there is still a long way to go in terms of stepping back from mere observations and consolidating empirical research to allow the development of fool-proof solutions. The more we understand about them, the more we can bring the perfect mining waste management solution to mining operators, with a view to eliminate the need for tailings dams thanks to the advancement in materials wet processing technology.
The total number of active tailings impoundments was loosely estimated at 3,500 in a variety of reports circa 2012, but this figure is disputed and no up to date evidence-based data exists to allow solid comparative research of the actual impact tailings dams across the world have on the environment. Correlatively, this means piecemeal solutions are the norm until a global approach to mining pollution can be considered. But piecemeal is not good enough in times of crisis.
Alarm bells have been resounding across the mining industry for years as numerous tailings dams’ failures have resulted in unspeakable damage to the environment and to the lives of thousands. Dam collapses have been affecting mining operations indiscriminately throughout the world from the Philippines to Russia, via Brazil and the United States to name just a few.
On a trip to Brazil in August to make the case for iron ore tailings management and beneficiation with CDE clients, I witnessed how the Samarco disaster has reshaped the environmental legislation in Brazil, now focused on active prevention coupled with remediation. The Samarco iron ore mine is a case in point when it comes to lessons learned from a disaster that was widely covered by the media in 2015. As the company took stock of the consequences of the dam’s failure on the socio-economic and environmental make-up of the region, this initiated comprehensive solution-led research with a view to ensure this could never happen again.
The Renova Foundation, created following the Samarco disaster to make sense of the tragedy and provide a practical solution to human, environmental and industrial challenges, sets the tone of action: knowledge-based restoration, reconstruction, production, all three strands being addressed in synergy to allow for a comprehensive solution to be achieved. In the context of the Brazilian government’s renewed focus on fighting waste pollution and turning every ounce of earth’s resources into valuable materials, it is timely for CDE to contribute to the edifice of change by developing bespoke modular tailings management and beneficiation solutions that actively contribute to restoring faith in the benefits of mining operations on the local economy and turning mining waste into revenue or materials for use in environmental rehabilitation.
In doing this, CDE seeks to repeat the success of its projects with Vallourec in Brazil. Ahead of the curve for tailings recovery and remediation in the region, Brazilian mining operator Vallourec and CDE have developed and successfully run a CDE dewatering system which has rehabilitated a tailings dam, helping to change the mindset towards tailings management by utilising recovered solids in ground remediation and road brick manufacture.
The proof is in the process: six EvoWash™ washing units dewater 30,000 tonnes per month of materials which are stockpiled as a dry product. Two banks of cyclones remove 30% of the mass (15,000 tonnes per month) to a filter press. The resulting cakes are used in soil composition and road brick manufacture. Strikingly, this bespoke modular wet processing solution allows for 45,000 tonnes of material to be diverted from Vallourec’s tailings dam on a monthly basis.
On the strength of this significant achievement in Brazil – the process being replicated with adequate materials and needs-based variations across the world – CDE is working on becoming a positive actor in the clean-up effort emanating from the Samarco legacy. As the business continues to develop ever more efficient means to manage tailings whilst adding value to mining operations, modular tailings recovery systems are set to become the next priority for companies under pressure to meet both their business and environmental targets.
CDE’s ‘New World of Resource’ ethos runs through every strand of the business, embedding a commitment to reduce waste as well as remediate and turn it into value. Not only does CDE’s patented technologies allow for clean and energy-saving materials wet processing operations, but the company’s innovative approach to waste management also opens up a new world of possibilities that involve the transformation of waste into high value construction products whilst ultimately eliminating the need for settling ponds and tailings dams.
CDE has the solution. Let’s talk.