Gold Mining Reinvented: Maximizing gold recovery while minimizing cyanide consumption

The following is a guest feature written by CyanoGuard, one of the 15 startups selected to participate in Prospect Mining Studio’s 2020 cohort.

Gold extraction using cyanide was first introduced in 1880s. It is the most common and efficient method of extracting gold, especially for low-grade ore. The process involves treating the ore with an aqueous solution of sodium cyanide. About 90% of today’s gold production involves the use of cyanide, making gold cyanidation one of the most predominant technique in leaching gold. Unfortunately, as cyanide is highly toxic, there have been some serious environmental accidents. In 2000, the cyanide spillage accident in Baia Mare, Romania resulted in cyanide leaks into the Tisza river, part of the Danube river system, killing most of the fish stock and destroying the surrounding biodiversity. Despite the accident, the European Commission rejected a proposed ban on cyanide in mining due to the lack of better alternative technologies. However, the conclusion of the International Cyanide Management Code (Cyanide Code) followed. With no better gold leaching alternatives, cyanide use and management remain one of the key pressing issues facing the gold mining industry.

Research also shows that the operating cost of primary gold mines have been on the rise, driven by fuel cost, electricity and consumables costs (such as cyanide and detox reagents). Declining ore grades also mean that many gold producers are likely to use more cyanide than necessary to ensure maximum gold recovery, resulting in the need for more detox reagent to treat tailings. Finding the right cyanide level is a delicate process and requires technology that can assist mine operators to make accurate measurements at various points in the gold extraction process. Up until today, the process in cyanide monitoring and control remains a very manual and tedious process — not only do mine operators may have to wait for days to get test results, the measurements are prone to error as a result of variations in sample collection. It is estimated that inefficient cyanide and leaching process control result in losses for gold mines exceeding 5 billion USD each year.

Likewise, greater focus on sustainability from investors has also placed an urgency to implement mining processes that fulfills reporting of mining activities according to responsible mining standards. Meeting such reporting standards means mining operators will require tools that will allow them to easily document data points that are necessary for such reporting without causing any unnecessary interruptions and downtime to operations.

Founded in 2016, CyanoGuard is Swiss-based chemtech startup dedicated to shaping the future of cyanide detection, monitoring and optimization for gold mining applications. The novelty of CyanoGuard’s technology lies in the patented single-use test cartridge which changes in color instantaneously based on cyanide concentration in the sample solution. CyanoGuard’s next generation cyanide management solution combines these single-use test cartridges with a handheld device that is connected to an AI-based online monitoring platform. Once the sample solution is passed through the cartridge, the user will only need to insert the cartridge into the handheld device which then reveals digitally the cyanide concentration to a resolution of 0.1 ppm in seconds. This data is then ready to be transmitted together with the GPS location into CyanoGuard’s cloud platform. With such solution, mine operators can make measurements onsite anytime and decide instantaneously on necessary cyanide adjustments that will optimize gold recovery.

First pilot tests suggest that the solution can help to reduce cyanide consumption and costs by 15% and enable mines to increase their gold recovery by 2% without any capital expenditure requirement. The fast, safe and easy-to-use solution brings not only cost savings and operational efficiency for mine operators but also helps mitigate the risks of cyanide-based gold leaching and minimize environmental footprint by reducing the use of cyanide, detox reagent and water. All measured data points are transmitted and secured in real-time in an AI-based cloud platform, allowing mine operators to have an overview of their cyanide usage. The stored data also allows them to keep an overview of their cyanide usage for environmental, social and governance (ESG) reporting purposes and share this data with stakeholders, increasing the transparency of mining operations.

CyanoGuard’s next generation cyanide monitoring solution integrates automation, analytics and artificial intelligence (AI) that helps mine operators make empowered decisions for responsible mining. Particularly against the backdrop of unprecedented COVID-19 pandemic, we are still able to deliver our solutions onsite and onboard mine operators remotely. As the mining industry faces increasing pressure to meet productivity and sustainability standards, the solution is one of a few that can truly have a long-term impact in terms of safeguarding the environment and helping the mining industry make the digital transformation into building smart mines of the future. We are currently in the process of kicking start our pilot studies and will therefore like to invite readers to get in touch, visit our website and join our upcoming webinars to learn more about the opportunities that our technology and our pilot program can offer them.