Posts By: rwallace

Making pyrrhotite waste remediation pay for itself

Researchers at the University of Toronto are working on developing a bioleaching process to extract nickeliferous pyrrhotite waste from tailings ponds in the Sudbury area in order to remediate the land and recover up to $11 billion worth of nickel

University of Toronto researchers are working to develop a bioleaching process that could help mining companies reclaim tailings ponds and recover up to $11 billion worth of nickel from them in the process. Courtesy of Glencore

Bacterial mutants and hydrogen peroxide may be keys to reclaiming value from tailings ponds clean-up

By Alexandra Lopez-Pacheco (Article was originally published in CIM Magazine here. )

While the technology could offset the cost of remediating the tailings ponds, according to the researchers the process to extract nickel from pyrrhotite is complex. A combination of bacterial mutants and hydrogen peroxide may be key to not only remove reactive material from the tailings and leave behind a benign product, but to extract billions of dollars worth of nickel and other metals.


RSVP | Lassonde Pivot Point Event with Zita Cobb at the University of Toronto


Lassonde Pivot Point Event with Zita Cobb

An Unexpected Resource
Exploring mining’s complicated relationship with community

An invite-only evening with guest host Pierre Lassonde and special presentation by Zita Cobb, co-founder of the Shorefast Foundation and member of the Order of Canada.

Lessons from a dying island’s economy and the woman who had the courage to re-imagine a new future.

_____________________

If you are interested in attending this event please reach out to:

Rachel Wallace
Strategic Development & Communications
r.wallace@utoronto.ca

 


Lassonde Mineral Engineering Team Places FIRST in 2018 Goodman Gold Challenge

Team members: Mark Umanec, Ice Peerawattuk, Marko Lopac and Dalton Veintimilla accepting their first place award at the 2018 Goodman Gold Challenge in Sudbury on January 28th.

Beating out competitors from the Schulich School of Business, Laurentian University, Queen’s University and the University of Kentucky, the Lassonde Mineral Engineering won first place in the 2018 Goodman Gold Challenge in Sudbury on January 28th, 2018.

The Goodman Gold Challenge is a hands-on investment mining management competition for business, geology and mining students across North America.  Applying their academic course work, students gain real-life experience interviewing three gold mining company CEOs on their respective current and future financial standings. The gold companies, currently trading on the TSX or TSX-V included: Wesdome, Nighthawk Gold Corp, and Sabina Gold & Silver Corp. Upon evaluation, each team recommended the gold company they thought would provide the best potential investment opportunity.

The winning 2018 Lassonde Mineral Engineering team members Mark Umanec, Ice Peerawattuk, Marko Lopac and Dalton Veintimilla presented their recommended investment deck to a panel of experts from RBC Global Mining & Metals Group, Kinross Gold, Canaccod Genuity, MNDM and Paul Martin, President & CEO of Detour Gold with David Harquail, President & CEO of Franco-Nevada.

“We want to thank Mike Chen (MIN 1T4) for helping us get Waterton Global Resource Management to sponsor our team financially and also giving us the chance to present our pitch to them and get feedback before we competed,” said Marko Lopac, 4th Year Lassonde Mineral Engineering student.

This is the first year the Lassonde Mineral Engineering team participated in the Goodman Gold Challenge however this is not their first title win in a case study challenge. The Lassonde Mineral Engineering team has had some recent great showings in national and international competition including: the Canadian Mining Games, the World Mining Competition and the OMA MINED Open Innovation Challenge. See below for some highlights:

1st Place: 2015 World Mining Competition

Team members: Matthew Hart, Blake Baek, Peter Miskiel and Daryl Li.

3rd Place: 2017 World Mining Competition

Team members: Mark Umanec, Marko Lopac, Romy Done and Icep Peerawattuk.

1st Place: Jackleg Challenge 2017 Canadian Mining Games

Team members: Marko Lopac and Jack Lindsay.

3rd Place: 2017 OMA MINED Open Innovation Challenge

Team members: Matthew Hart, Marina Reny, Yoko Yanagamura and Justin Samardzic.


Lassonde Pivot Point Campus Edition

Registration is now closed.


Elements of bio-mining: Engineering collaboration aims to turn mine waste into valuable metals

  • Mine drainage

    An industry-academic collaboration led by U of T Engineering professors is studying the use of microorganisms to treat mine waste in tailings ponds. The researchers also hope to extract valuable metals that could offset the cost of processing. (Photo: mine drainage- Sean Caffrey)

  • Mine drainage

    An industry-academic collaboration led by U of T Engineering professors is studying the use of microorganisms to treat mine waste in tailings ponds. The researchers also hope to extract valuable metals that could offset the cost of processing. (Photo: mine drainage- Sean Caffrey)

  • Mine drainage

    An industry-academic collaboration led by U of T Engineering professors is studying the use of microorganisms to treat mine waste in tailings ponds. The researchers also hope to extract valuable metals that could offset the cost of processing. (Photo: mine drainage- Sean Caffrey)

 Originally posted on U of T Engineering News by Tyler Irving

They are invisible to the naked eye, able to withstand extreme conditions and capable of breathing rocks. They are the microbes that thrive in tailings ponds at mining sites around the world, and a team of Canadian researchers believes they are the key to transforming waste material into something much more valuable.

“There are bugs that thrive on metabolizing sulfur, others on metabolizing iron,” says Professor Vladimiros Papangelakis (ChemE). “If we can control such biochemical reactions, we could both remediate the waste and recover valuable metals that could pay for the cost of processing.”

Papangelakis, along with Professor Elizabeth Edwards (ChemE) is leading the Elements of Bio-mining project, a multidisciplinary collaboration between U of T Engineering, Laurentian University, and the University of British Columbia (UBC), as well as a number of technology, engineering and mining companies, including Glencore, Vale, Teck, Barrick and Hatch.

For a full list of team members and partners, visit the Elements of Bio-mining website

Together, the team is developing ways to process a number of different types of material left over from mining activities across Canada, from nickel mines in Sudbury, Ont. to coal mines in British Columbia. They aim to understand how native microorganisms at these sites convert chemicals one form to another, and how they might encourage certain beneficial reactions while discouraging others.

Elements of Bio-mining team

Members of the Elements of Bio-Mining project team at the In the Footsteps of Sudbury’s Minersexhibit at Science North in Sudbury, Ont. (Photo: Sean Caffrey)

For example, nickel refining produces tailings, which are rich iron sulfide. When exposed to the oxygen in the atmosphere, chemical reactions begin to convert the sulfides into sulphuric acid. This process — known as Acid Mine Drainage (AMD) — is catalyzed by microorganisms that live in the rainwater or melting snow that washes over the tailings.

The sulphuric acid can dissolve any nickel that remains in the tailings, as well as other metals such as copper and zinc and even toxic elements like arsenic, selenium, cadmium, mercury. Because of its toxic and acidic nature, tailings water cannot be discharged into the environment unless it is collected and treated. Currently, these tailings sit in enormous ponds around the mine sites — the water covers the tailings, acting as an oxygen barrier and slowing the AMD process.

Papangelakis and his collaborators hope to treat these tailings using bioreactors, vessels that enable them to control the temperature, pH, dissolved oxygen levels and other culture conditions. One idea is to encourage the growth of organisms that would convert the sulfide not into sulfuric acid, but into elemental sulfur, which may have some value if recovered. At the same time, the metal-rich wastewater could be captured and refined to recover metals, potentially providing a revenue source to offset the cost of treatment.

Other members of the team are looking at the waste rock that was separated before the refining process. Here sulfur is less of a problem, but there are still potentially valuable metals that could be recovered. Professor Nadia Mykytczuk of Laurentian University is studying ways to encourage bacteria to selectively dissolve these metals from heaps of rock, a process known as in-situ bio-leaching.

“There is a large diversity of organisms out there that we are only starting to understand,” says Mykytczuk. “Some of them like oxygen, but others thrive under anaerobic, or oxygen-free conditions. We’re looking at the whole range of possibilities, and once we find something promising, we can decide how to address specific types of waste.”

A third branch of the team is focusing on waste from coal mines, which is often high in selenium. Though a necessary nutrient in small amounts, too much selenium can be toxic to many forms of life; for example, it can interfere with the development of fish embryos, reducing the number of viable adults in the next generation.

“There are some microorganisms that can actually use selenate, the dissolved form of selenium, for energy,” says Professor Sue Baldwin of UBC, another one of the project partners. “They take the selenate and turn it into elemental selenium, which precipitates out as nanoparticles attached to the organism’s cells. In this form, it’s no longer dissolved and you can just filter it out of the water.”

Baldwin points out that selenium is just one of many pollutants that exist in waste from coal mining. And as with nickel mining, there may also be valuable metals or other materials that could be recovered through biochemical transformations.

Papangelakis says that there may be up to $7 billion dollars worth of nickel alone locked in the tailings from Sudbury’s mines. “The question is, can this value be recovered in a way that makes the treatment and remediation process economically viable?” he says.

In addition to the universities and the industrial partners, the project has attracted support from a number of research funding agencies, including the Natural Sciences and Engineering Research Council (NSERC), Genome British Columbia and Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO). Most recently, the project received $4 million from the Ontario Research Fund.

“It’s a very challenging problem that needs to be solved,” says Papangelakis. “But we have assembled a very good knowledge base, with experienced people in mining, chemistry, biochemistry and process engineering. There will be cross-fertilization and new ideas, which will create a springboard to understand new science and launch initiatives we haven’t thought of yet. To me, this is the most exciting part.”


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