Biomining '23: a summary of the technical presentations

Biomining '23, MEI's 11th International Symposium on Biomining was held at the National Maritime Museum Cornwall in Falmouth, UK, from June 5-6, 2023. It was organised in consultation with Prof. Sue Harrison, of the University of Cape Town, South Africa and Dr. Chris Bryan, of BRGM, France, with media Partners International Mining and Minerals Engineering and Industry Advocates the Critical Minerals Association.

Following is a summary of the presentations made in the technical sessions over the two days.  The draft papers associated with the presentations are available online as open access. The drafts have not been refereed, but all the presenters have been invited to submit their final papers for peer-review to a virtual special issue of Minerals Engineering.

Monday June 5th

The conference was opened this morning by MEI's Jon Wills, who welcomed the 55 delegates from 14 countries, and then the proceedings got off to a fine start with a keynote from Axel Schippers, who is highly respected in the field of biohydrometallurgy. He has been with the Federal Institute for Geosciences and Natural Resources (FIGNR) in Germany since 2007 and now heads the Geomicrobiology unit. In 2006 he qualified as lecturer in microbiology and geochemistry at the Leibniz University of Hannover and was appointed as Professor in 2011. His keynote lecture showed how biohydrometallurgy offers various process options including bioleaching, biooxidation, biomineralization, bioprecipitation, biosorption and bioelectrochemistry for metal recovery from primary and secondary resources.

Axel was a co-author of the next presentation, by his FIGNR colleague Stefanie Hetz, an environmental microbiologist with focus on nitrogen, sulfur and iron cycles. She did research at the Universities of Bayreuth and Hannover before moving to FIGNR in 2021 and her presentation explored options for stirred-tank reactor and column bioleaching of nickel and cobalt from Brazilian laterite ores.

Stefanie Hetz and Axel Schippers

Ana Santos has presented work at previous MEI biomining conferences as a PhD student at Bangor University, UK, from where she graduated in 2018 before working as a post-doctoral researcher until 2021. She joined London's Natural History Museum in February 2022 as a Research Fellow in Geomicrobiology and she has been working on the development of novel and improved biotechnologies to extract base and rare-earth metals from mine wastes and from new, untapped resources such as marine polymetallic nodules, the subject of her presentation.

Ana Santos (right) with Paula Morais of University of Coimbra, Portugal

Paul Norris, of the University of Exeter, UK is currently biohydrometallurgy consultant for GSL in Cornwall, following fifty years of research at the Universities of London and Warwick, with over 80 publications concerning microbiology of extreme environments, acidophilic microorganisms and biohydrometallurgy. This morning he discussed the continuous bioreactor processing of a nickel sulfide concentrate with moderately thermophilic bacteria and archaea.

Paul Norris (left) with Dave Dew (UK), Anders Sand (Sweden)
and Anne-Gwenaelle Guezennec (France)

Ivan Nancucheo (left) of the Universidad San Sebastián, Spain, has a PhD degree in microbiology from Bangor University, where he was a post-doc in a bioreductive dissolution of laterites project led by Professor Barrie Johnson. He worked in Brazil at Vale Mining Company for three years and during this period he was a visiting scholar at Massachusetts Institute of Technology. He presented work on the recovery of “pure” CuS nanoparticles using biogenic H2S from a complex bioleach liquor.

Alfonso Mazuelos is a Senior Lecturer in Chemical Engineering at the University of Seville, Spain and he discussed continuous ferrous iron biooxidation in a packed-bed bioreactor at very extreme acidity conditions.

Blanca Perdigones is a PhD student at the Department of Chemical Engineering at the University of Seville. She holds a degree in Biochemistry from the Universities of Seville and Malaga, a Master's degree in Water Quality Sciences and Techniques from the University of Granada and a Master's degree in Advanced Studies in Chemistry from the University of Seville. Blanca has collaborated in research in international environments such as in Chile and Argentina. She is currently a grant holder in the European RAWMINA project within the framework of the European Union's Horizon 2020 research and innovation programme, where she is developing her thesis on the starting-up of bioleaching bioreactors. She presented work on adaptation of an iron oxidizing culture to extremely high Fe concentration by a programmed fed batch bioreactor.

Blanca and Alfonso

The presentation from Laura Castro (left), an Assistant Professor at Complutense University of Madrid, Spain took us up to the lunch break. She discussed the isolation of a halotolerant and iron oxidizing bacterium from Rio Tinto, Spain, with potential for seawater bioleaching.

Paul Norris, in his second presentation of the day, discussed the carbon dioxide requirements and fixation by various mineral-sulfide oxidizing bacteria.

Didi Makaula is a scientist in the Biometallurgy Division at Mintek, South Africa. He also works in partnership with commercial organisations to improve the growth of bioleaching cultures at different temperature profiles and he presented work aimed at bridging the temperature gap from thermotolerant mesophilic to moderate thermophilic conditions. The insights gained from these studies will assist with the selection, adaptation and maintenance of the best performing cultures in these higher temperature profiles.  

Didi Makaula (right) with Dave Dew (UK) and Nokubonga Zulu (South Africa)

Megan Barnett (left) has been at the British Geological Survey since 2015. Her biomining research had focused on REE, but she also has interests in the sustainable extraction of other critical metals. Megan discussed changing REE leaching profiles by bioleaching with methylotrophs.

Fernando Vera is a PhD student at the Pontifical Catholic University of Valparaíso, Chile and he explained how copper smelters currently deal with arsenic contamination in processed ores. Chemical processes for removing arsenics are expensive and ineffective, and he evaluated the biological treatment of arsenic in effluents from a copper smelter gas washing plant using a consortium of iron-oxidizing mesophiles (35 °C) adapted to As(III). 

Fernando (left) during one of the morning breaks

Ishaaq Hajee holds an MSc in chemistry, having majored in chemistry and biochemistry at the undergraduate level. He then entered the mining industry and has worked at refineries, froth flotation plants, and various chrome mines across Africa. He is now a PhD student at the University of Cape Town, and presented his work which involves using naturally occurring bacterial phenomena to help prevent acid rock drainage, a process which threatens to pollute the already scarce water resources in South Africa.

Ishaaq (right) with UCT colleagues Sue Harrison and Msimelelo Gcayiya

After completing her BSc and MSc studies in Life Science & Technology at the Technical University of Delft, Charlotte (Lot) van der Graaf went to Wageningen University & Research, both in the Netherlands, for her PhD research. There she focused on microbial and chemical sulfide production at acidic conditions, with the aim of improving process economics of the treatment of metalliferous waste streams (acid mine drainage, metallurgy waters) through metal sulfide precipitation. Lot is currently a postdoctoral researcher at the University of Cadiz, Spain, where she studies metallic copper formation in acid mine drainage biofilms found in the Rio Tinto area (Huelva, Spain), the subject of her presentation.

Lot van der Graaf with Stefanie Hetz (Germany)

Bailee Johnson completed her B. Eng in Materials Engineering at McGill University, Canada. Throughout her Bachelors degree, she worked in Prof. Kristian Waters' mineral processing laboratory as an undergraduate research assistant; as a result of her work, she has contributing authorship on two published academic papers as well as a first-place-winning technical report presented at Canadian Mineral Processors 2018. On graduation, Bailee worked for CiDRA Minerals Processing and supported the development and scale-up of a novel mineral processing technique. Her work took her to concentration plants across North and South America; she served as onsite project lead for two of these projects. Now completing her MSc at McGill University, she is a CMP 2021 Scholarship recipient and McGill Graduate Excellence Fellow for 2021 and her paper, the last of the day, was an investigation of froth flotation of municipal wastewater treatment plant biosolids for phosphorus separation.

Bailee with McGill colleague Ozan Kokkilic 

After a long day it was good to get out into the warm Cornish sunshine for the 3 mile guided coastal path walk, followed by drinks at the Chain Locker pub (see Monday at Biomining '23).

Tuesday June 6th

Karen Hudson-Edwards got the day underway with a keynote lecture reviewing the biomining of copper and other technology metals. Karen is Professor in Sustainable Mining at the Camborne School of Mines and Environment and Sustainability Institute at the University of Exeter, UK. She was the 2012/3 Mineralogical Society of Great Britain and Ireland’s Hallimond Lecturer, the 2016 Australian Institute of Mining and Metallurgy New Zealand's Visiting Lecturer and the 2019 European Association of Geochemistry’s Distinguished Lecturer.

Karen (right) with Sue Harrison and Carmen Falagan at Monday's sundowner at the Chain Locker

Klemens Kremser is a post-doctoral researcher at the University of Natural Resources and Life Science Vienna and the Austrian Centre of Industrial Biotechnology. He discussed Project FuLIBatteR, future lithium-ion battery recycling for the recovery of critical raw materials.

Klemens with Daniel Kupka (Slovakia)

Lidia Garcia Saez (left) is a PhD Researcher at the Universitat Politècnica De Catalunya, Spain, working on the recovery of valuable metals from lithium-ion batteries. Her presentation was on a multi-step bio-based process for recovering valuable metals from spent lithium-ion batteries without extreme pH and temperature.

After graduating in metallurgy in Iran, Mohammad Khoshkhoo worked for a few years there in the mining sector before moving to Luleå, Sweden in 2007, where he completed his master and doctorate studies in process metallurgy. He is now a Senior Development Engineer at Boliden Mineral, Sweden, and he presented results of a pilot campaign for the recovery of battery metals from low-grade mining residues via stirred tank bioleaching.

Mohammad with Blanca Perdigones (Spain)

Jens Markowski is a scientific assistant at the Brandenburg University of Technology, Germany and he described his experiences in the commissioning of a bioleaching plant for the recovery of gold from printed circuit boards.

Jens with Stoyan Gaydardzhiev (Belgium)

Anna Sieber holds a master's degree of Biotechnology from the University of Natural Resources and Life Sciences (BOKU) in Vienna, Austria. After working for 2 years in industrial research, she started her PhD at K1-MET in cooperation with BOKU. Her research focuses on the recovery of metals from various waste stream and her presentation looked at the application of spent brewer’s yeast as a selective biosorbent for metal recovery from polymetallic waste streams.

Rebeka Frueholz is also representing K1-MET in Austria and is currently pursuing a PhD in the field of bioleaching using thermophilic bacteria. She discussed zinc removal from metallurgical dusts with sulfur-oxidizing bacteria.

Rebecca and Anna with their K1-Met colleague Lalropula Lalropula (right) and Stuart Wagland (UK)

Eva Pakostova graduated with a PhD in Biochemistry at the Masaryk University, Czech Republic, in 2016. She then worked as a post-doc at Bangor University, developing a new mining concept for extracting metals from deep ore deposits, using biotechnology. During another post-doc at the University of Waterloo, Canada she contributed with her microbiological expertise to the development of improved strategies for managing mine-waste environments and implementation of the innovative remediation technologies at an industrial scale. Eva joined Coventry University, UK, as Assistant Professor in 2020. She develops novel and improved biotechnologies to extract base and precious metals from primary ores and secondary (mine and electronic wastes) sources. In her presentation, co-authored with Neil Rowson of Bunting-Redditch, UK, she discussed the bioleaching of metals from automotive catalysts, focusing on magnetic separation and base metal removal using acidophilic bacteria.

Eva (right) with Daniel Kupka, Lenka Hagarova and Zuzana Bartova of Slovakia

Antonio David Dorado is a researcher at the Universitat Politècnica De Catalunya, Spain. He has a UPC Doctorate Extraordinary Award in Natural Resources and Environment and has spent time abroad, with postdoctoral studies at the University of Nueva Gales del Sur, Sydney, Australia and the PUC of Valparaíso, Chile. He described a high productivity bioprocess for obtaining metallic copper from printed circuit boards.

Antonio David relaxing at the Chain Locker sundowner

MEI conference consultant Sue Harrison, Director at the Centre For Bioprocess Enineering Research, University of Cape Town, South Africa, needs little introduction. She discussed the bioleaching of printed circuit boards in a continuous two-stage system including a re-circulating packed-bed reactor for improved regeneration of ferric ion.

Lalropuia Lalropuia currently works as a PhD Researcher at K1-MET, Austria and his research focuses on bioleaching of critical metals from spent lithium-ion batteries, the subject of his presentation. Lalropuia has a bachelor's degree in Mining Engineering from Bhagwant University, India and a master's degree in Advanced Mineral Resource Development from TU Bergakademie Freiberg, Germany and Montan University Leoben, Austria.

Carmen Falagan has been working in biomining for the past years in the European project NEMO at the University of Exeter before moving to the University of Portsmouth as a lecturer in Environmental Microbiology. She is interested in bioremediation and in developing new bioleaching approaches for mine tailings to minimise the impact of mining in the environment. Her presentation evaluated a pilot scale study for base metals recovery from low grade sulfidic residue ore.

Stoyan Gaydardzhiev also needs little introduction, as he is a familiar face at MEI Conferences. He is Professor and Head of the Mineral Processing and Recycling Unit at the University of Liege, Belgium, involved in various EU, national and regional research projects in the area of the circular economy and recycling and valorisation of metals. Taking us to the lunch break, he discussed the bioleaching of black mass from spent LiBs.

The final session began with a presentation from Douglas Pino Herrera, a process engineer/researcher at BRGM, France. He has a PhD in Environmental Technology from the University Gustave Eiffel in Paris, and he discussed bioleaching process development and optimization to recover critical raw materials from sulfidic mining wastes.

Douglas (3rd left) at the Chain Locker sundowner

Paula Morais. of the University of Coimbra, Portugal, works in environmental microbiology and she is the curator of the UCCCB Bacterial Culture Collection which constitutes an infrastructure of the University of Coimbra. Her presentation looked at biopolymer stabilization of bioleached mine residue to produce technosol.

Another speaker who needs little introduction is Barrie Johnson, Professor Emeritus at Bangor and Coventry Universities and a Scientific Associate at the Natural History Museum, London. He compared two bioleaching protocols for extracting and recovering nickel from pyrrhotite waste.

Barrie Johnson (left) at the welcoming reception

Zuzana Bártová is a Research Fellow at the Institute of Geotechnics at the Slovak Academy of Sciences, Slovakia. She studied biology as her major at the University of Pavol Jozef Šafárik in Košice, Slovakia. Her main focus is on bioleaching processes using microorganisms, bacterial growth kinetics and raw materials acquisition from acid mine drainage and she discussed metal recovery and remediation of mine water effluent from a siderite deposit at Nižná Slaná, eastern Slovakia.

Zuzana (right) at the Chain Locker sundowner

Jaeheon Lee (left) is an associate professor in the department of mining engineering at Colorado School of Mines, USA. Prior to that he worked for Newmont and Barrick as a corporate metallurgical engineer and held the position as a faculty in the department of mining and geological engineering at the University of Arizona. He discussed the role of biohydrometallurgy for mine tailings repurposing and valorization.

Anne-Gwenaelle Guezennec, of BRGM, France is a well known expert in biohydrometallurgy and more specifically in bioleaching process design. She highlighted pilot-scale demonstrations of innovative biohydrometallurgy for sustainable valorisation of mining waste.

Anne-Gwenaelle (centre) at the welcoming reception

Ipek Tezyapar Kara (left) is a PhD Researcher at Cranfield University, UK. Ipek has a bachelor’s degree in Environmental Engineering from Kocaeli University, Turkey and she completed her M.Sc. degree at the same university in 2019. She discussed the bioleaching of metal ions from Basic Oxygen Furnace sludge and dust by Acidithiobacillus ferrooxidans.

The final presentation of the conference was deferred from yesterday, as Nokubonga Given Zulu was delayed due to the travel disruption. Given was born and raised in South Africa, in a small village in KwaZulu Natal. She is a graduate in Extraction Metallurgy from the University of Johannesburg (UJ) and is currently pursuing an MEng in Extraction Metallurgy at UJ, majoring in bioflotation and bioleaching.  She has also worked at the Kibali Gold Mine (Barrick Gold Corporation) as a trainee metallurgist. Her presentation investigated the application of Acidithiobacillus ferrooxidans in biomodification and pre-concentration of base metal sulphides prior to flotation.

Nokubonga looking after the drinks at the Chain Locker!

After a brief summary of the conference from Prof. Sue Harrison, MEI's Amanda Wills thanked everyone involved with the conference and invited everyone to join us in Cape Town in two years time for Biomining '25, before we all adjourned for a farewell Cornish Cream Tea, making sure that the jam was put on the scones before the cream!

We would greatly appreciate your views on the conference via comments to this posting.  

All the photos on the blog postings, and more, are in a Biomining '23 Album. Please feel free to download photos for your personal use. If you would like to use any photos on a company website, please acknowledge the source (MEI Blog).

#Biomining23   @barrywills