Bradshaw Research Institute for Minerals and Mining

Hope springs eternal, so does life…

Researchers are uncovering life in the harshest places on earth, in places where no one would expect anything to survive, the waste produced from mine sites and illegal mining. These forms of life are leaving researchers clues about how to possibly treat mining waste and recover valuable metals.

According to University of British Columbia Professor Steve Hallam, there are an estimated nonillion (or 1,000,000,000,000,000,000,000,000,000,000) prokaryotic microorganisms on Earth. Their abundance eclipses the number of stars in the known universe, the number of neurons in our brains, and all of our synapses combined.

Scientists have barely developed the capacity to explore and map this micro universe, but new advances in computing and ground breaking research is leading the way to possibly uncover and beginning the process of mapping this micro universe. 

Carlos Alvarez-Rosario is a Postdoctoral Researcher with the University of British Columbia (UBC) department of Chemical and Biological Engineering. His research focuses on recovery of copper from mine-impacted water using native microorganisms isolated from copper mines.

Carlos graduated in Industrial Engineering from the University of Ibague (Colombia) and obtained a PhD in Chemical Engineering at the University of Sao Paulo (Brazil) where he had the opportunity to work in bioprocesses applied to the mining industry. 

Carlos also has studied e-waste recycling by biological methods known as bioleaching and in treatment of industrial effluents with microorganisms.

BRIMM had a chance to interrupt Carlos and his busy schedule to get some personal insights into his research and what is going on at BRIMM. 

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Thank you very much for your time today, let’s begin with a little bit about your background and how you ended up at the UBC?

Carlos Alvarez: I am a trained industrial engineer and I worked in Colombia, in the polymer industry for six to seven years. After that I went to Brazil to complete a Master’s degree and PhD. During these studies,  I worked with bacteria that had bioremediation properties and , I specialised in the microbial treatment of contaminated effluents and solid waste..

I had the opportunity to study bacteria isolated from gold mines, which have a great potential for degrading cyanide in effluents from artisanal gold mining. I also worked with other types of bacteria that play a crucial role in the copper leaching process, using them to recover copper from electronic waste.

I have always had the intention of being part of UBC because it is a world renowned university, especially in mining. My journey to UBC came about through Professor Dr. Susan Baldwin, who is an expert in the field of bioremediation and has experience in metal recovery from mining waste. She is part of the BRIMM Institute and is involved in a copper bioremediation project using microorganisms. It was through this project that I had the opportunity to take part and contribute with the BRIMM project at UBC. 

You studied microorganisms that would treat mine waste?

Carlos Alvarez: Yes. I studied bacteria that help in the treatment of contaminated effluents, such as in the case of cyanide contamination at mine sites. It is a big problem. Cyanide solution is very often used in South America in artisanal mining operations for the extraction of gold from ores. This is a big problem for Colombia, Peru, and Brazil.

I isolated microorganisms from this waste that could tolerate a high concentration of cyanide and which could remove this chemical. This was the focus of my PhD. I found three microorganisms that had tolerance for the toxic conditions in mining waste and have the ability to use cyanide as a carbon source and convert into a less toxic substance.

How did you find these microorganisms? 

Carlos Alvarez: In our case we obtained samples from sites close to the Peruvian Amazon. The samples were obtained from abandoned artisanal gold mines.. Typically, after the artisanal gold extraction process, the sites are abandoned, leaving the mining tailings exposed. We used samples from these tailings to isolate and identify the microorganisms present in them. This work was conducted in collaboration between universities in Peru and Brazil.

Is there life in mining waste and tailings? 

Carlos Alvarez: Yes, of course, there are many microorganisms. depending on the type of tailings and the characteristics of the site, both chemical and physical, we can find different microorganisms. In fact, this is one of the objectives of the Mining Microbiome Analysis Platform (MMAP) project. 

Our focus in this project is to isolate and identify copper tolerant microorganisms from different copper mines. In this case we are using samples of tailings, waste rock, surface water and groundwater from these copper mines to isolate and identify microorganisms.

It appears that nature offers clues about how to survive in toxic environments.

Jetti Resources and Dynasty are companies that are looking to recover copper from lower grade material and remediate tailings waste.  Do these microorganisms offer the same potential? 

Carlos Alvarez: Normally they work with bioleaching processes, which in these cases, they use bacteria that assist in the copper leaching process. This type of bacteria is widely known, such as Thiobacillus Ferroxidans bacteria, which utilise the iron present in the ore to help solubilize copper, but my work shows the applications of microorganisms in mining extend beyond just treating mine waste. 

For instance, a major focus of my PhD work was on obtaining metals from urban mining. We use the same technique and the same bacteria employed in the bioleaching process, but instead of mineral ore –  we used electronic waste like computers, cell phones and other electronic waste. 

Electronic waste materials were separated from their plastic compoenents, leaving only the part containing metals, which is typically the circuit board. This material is then crushed and added to a solution containing the bacteria. This treatment resulted in an increase in the copper recovery rate. I would see recovery rates above 50% using microorganisms. 

It is worth noting that in our current project at UBC, we aim to obtain microorganisms that can tolerate copper and use them in mine impacted water to remediate these effluents while attempting to recover the copper at the same time. This is a different approach from the leaching process.

Are you trying to scale the technology for commercial applications? 

Carlos Alvarez: Currently, we have to focus on the biological mechanisms of these organisms. Before any commercial applications we need to understand what happens between the bacteria and the copper in solution and use this knowledge to develop a new process. 

Can microbes replace traditional mining? If we have these microbes now…can they mine the copper for us?

Carlos Alvarez: No…not yet. We are currently studying how bacteria can help to recover copper. One hypothesis is that the bacteria can help to precipitate the copper in solution. Another hypothesis we are exploring is that the bacteria can produce a biopolymer through a defence mechanism and this biopolymer can sequester the copper and precipitate it.

I think that microorganisms can help in various processes within the mining industry as a complementary approach. It represents a low-cost and environmentally friendly alternative. However, I do not consider it a substitute for the traditional mining process.

What are your thoughts on working with BRIM?

Carlos Alvarez: Being a part of BRIMM has been a great professional experience. It is a pioneering group on a global level, where collaboration between the academic sector and industry has yielded excellent results. What catches my attention is that it is a multidisciplinary group in which different academic profiles, each with extensive experience and knowledge, contribute to the group´s development.. 

Thank you for your time and look forward to seeing what your work discovers.

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Carlos is one among many researchers working at the Bradshaw Research Institute for Minerals and Mining (BRIMM), tackling the legacy issues of the mining industry and building the solutions for the future to ensure the world has the minerals and metals it needs. 

By working across the UBC campus, we have access to top minds in the fields of Mining Engineering, Microbiology, Geology, Business, Policy, Data Science and more. It is through these connections that we build teams of researchers for the big mining problems of today.

One of the key aspects of BRIMM is driving this change through a multidisciplinary approach through our researchers, such as Carlos but also with input from key stakeholders in the mining industry, mining companies, communities and academia. 

If you have any ideas for research projects, please reach out to us here. We look forward to working with you.