Finding value in in-situ recovery

March 12th, 2020

Dr Chris Vernonby Dr Chris Vernon

Is in-situ recovery a viable path for mineral processing operations?

Last month, CSIRO held its inaugural Resources Innovation Showcase that focused on the future of mining and innovations that can reshape the way mines operate.

As part of the day, my colleague, Dr Laura Kuhar, presented on in situ recovery (ISR), a topic that is growing in interest around the globe.

Referring to the recovery of metals through the circulation of a fluid underground and the recovery of the valuable metal from the fluid at the surface for further processing, ISR is being viewed as an important step towards achieving ‘the invisible mine’.

As our industry faces increasing financial, social and environmental pressures that are affecting traditional mining and processing methods, new, sustainable and cost-effective options are required.

But, as with any new process or technology, there are some hurdles to wider adoption of ISR – primarily, that for various reasons, this method is not suitable for all deposits.

Given that this technology doesn’t have generic application, is it worth pursuing?

ISR faces both real and perceived challenges

There are a range of challenges (e.g., focus on productivity, capital usage, safety, declining grades, and community expectations) that have led to our industry exploring alternative metal recovery options.

Particularly with declining grades, the expense of building and maintaining mines and process plants can easily become cost-prohibitive.

This is compounded by investors’ diminishing willingness to finance operations due to perceptions around social license.

Communities are more aware than ever of what happens in their “backyard”, and our industry has responded by actively working towards sustainability and community engagement strategies as part of their operations.  The industry is actively seeking to change.

While in-situ recovery offers several solutions to some of these issues (including reduced disruption to land use and communities, and significantly less movement and processing of vast amounts of rock), it is not without its challenges.

Hurdles to the wider adoption of ISR include:

No guarantee of process viability

First and foremost, not all deposits are suitable for ISR, and considerable research is needed to assess the viability of a given deposit.

For example, the ability of the chosen lixiviant to access the mineral or metal of interest needs to be determined via testing of core permeability.

No generic track record

As with all things new, operations can be wary of investing in something that hasn’t strongly been proven to provide benefits or return on investment (ROI).

With such a small sample size of operations currently using ISR at the commercial scale (and it is predominantly limited to uranium and copper deposits), there is a need for companies to partner with researchers and conduct pilot and field ISR trials to prove viability.

Social perceptions

While established technologies have earned a degree of social acceptance through familiarity, emerging technologies may have to better negotiate a multiplicity of values, contested knowledge, regulatory frameworks, and uncertainty in the mind of the public.

This requires an increased focus on reducing harm (both real and perceived) associated with new and existing operations, decreasing the use of water, energy and other resources, and delivering value for the sector and their host communities, regions and countries.

Society and government effectively place a higher hurdle on new technologies.

Research provides benefits beyond ISR adoption

The biggest draw of ISR is its ability to offer a solution to many of the challenges our industry is currently facing, as mentioned above. ISR directly addresses some of the biggest problems by ensuring:

  • Significantly less movement and processing of vast amounts of rock (energy consumption, cost, tailings, and emissions reduced)
  • Lower-grade ore can be processed, both in greenfields applications and making the most of existing but depleted deposits
  • Less disruption to communities (less dust, noise, and haulage)
  • Possibility to explore areas that aren’t viable using traditional approaches (e.g. proximate to sensitive cultural and environmental sites)

Since not all deposits will prove viable for ISR (in its current state and with the technology currently available), are these benefits largely theoretical? The answer is, not necessarily.

While not every deposit is appropriate for ISR today, our initial research still offers encouraging opportunities for operations to gain significant understanding of their orebody and return on investment on a wider and longer-term scale.

The first step towards ISR is a program of research and testwork to better understand the deposit and mining operation, which involves three major areas:

  1. Containment and hydrogeological control
  2. Leachable value and appropriate in-situ chemistry
  3. Creating access to value minerals through increased permeability

Yes, this research will reveal if your deposit or existing operation is a good candidate for in-situ recovery today – or not.

But even for operations found not yet viable with today’s technology, the results obtained from the research can help identify technology bottlenecks and the innovation necessary to make such deposits viable in the future.

Mining3 are pursuing these ideas as part of their In Place Mining initiative.

It’s important to remember that in-situ recovery is just one stepping stone to overall mine optimisation and the invisible mine, not necessarily the final destination.

Case study: Successful adoption of ISR research at Kapunda

Environmental Copper Recovery is at the forefront of investigating ISR potential to recover stranded mining assets.

Through their collaboration with CSIRO and the University of Adelaide, they are assessing whether the technique can be applied at the Kapunda Copper Mine with potential improved financial and social outcomes.

From mining new deposits to improving outcomes for local communities, the success seen here through research planning, and community involvement, has been an indicator of how successful this technology can be for existing operations.

CSIRO ISR initiative recognising education and collaboration are the first steps to successful adoption

When it comes to in-situ recovery, challenges exist as we work towards wider industry adoption.

But multiple benefits still await those who invest in this avenue at this early stage.

ISR helps operations meet their needs of safety, productivity and lower cost, while also meeting external expectations of sustainability and community engagement.

Every site should consider the possibility when they’re looking to optimise their mine and make the decision based on comprehensive research.

At the Resources Innovation Showcase, we invited our industry partners to join us in our ongoing ISR initiative, which aims to:

  • Conduct research, development and innovation to facilitate the uptake of broader applications of ISR
  • Foster a collaborative ecosystem which brings together the multi-disciplinary expertise necessary to facilitate the uptake of ISR
  • Promote and identify opportunities for pilot-scale tests and field trials, leading to commercial take up

Education and expertise, not just viable technique and technology, are some of the biggest hurdles towards achieving invisible mines.

As the initiator of the ISR initiative, CSIRO and Mining3 are uniquely positioned to work with operations and industry bodies to further the adoption and knowledge of ISR.

A number of our experts will be presenting on the subject at the upcoming ALTA in-situ recovery conference, and we will be exhibiting at the event.

If you are interested in joining the conversation and learning more about ISR and the value it can bring to your operation, visit us at ALTA or contact Laura Kuhar at Laura.Kuhar@csiro.au or on +61 8 9334 8075. Or email me, Chris.Vernon@csiro.au, to discuss how our expertise and experience can help you.

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