Funded Projects

Mining, Manufacturing and Power Generation

Using Thermophilic Metal-Reducing Bacteria to Enhance Metal Recovery

Primary Investigator: Jeffrey Gralnick
Co-Investigators: Victoria Portuguez Molina (Undergraduate Research Scholar)
Industry Partners: NA
Award Type: Undergraduate Research Scholar

Problem: Mass production of electronics has increased demand for a range of elements. Recovery and reuse of metals from electronics is the only sustainable pathway forward. We hypothesize that thermophilic metal-reducing bacteria could be used to mobilize valuable metals from electronic waste.

Solution: Biomining, or the use of microbes to selectively solubilize valuable metals, is an emerging area of research. Thermophillic microbes may present a unique approach to mobilizing high-value metals (cobalt, silver, gold, rare earth elements, etc.) from mine and/or electronic waste streams.

Impact: In this basic research project, we will grow the Gram positive thermophile Thermincola under a variety of laboratory conditions to better understand the conditions that produce abundant cell mass. We will then use model E-waste components to test mobilization of metals under various conditions, quantifying a range of metals with ICP-MS.

Direct Carbon Dioxide Capture for Air Remediation in Minnesota

Primary Investigator: Sam Toan
Co-Investigators: Ian McNicholes (Undergraduate Research Scholar)
Industry Partners: NA
Award Type: Undergraduate Research Scholar 

Problem: The growth in global economies attributed to the emergence of new technologies needed for industrialization and the associated consumption of fossil fuels leads to serious environmental concerns such as climate change, acid rain, and smog formation. Climate change, resulting from the emission of greenhouse gases (GHG)– including carbon dioxide (CO2), which is the most prevalent – is considered the most serious.

Solution: We are proposing using a solvent based technology: catalytic amine based sorbent to capture CO2 from air. A metal based catalysts such as TiO(OH)2, Mg(OH)2, NaOH, TiO2, etc. will be used to combine with amine solution to create an effective capture sorbent. In this project, student will investigate the effectiveness of different metal based catalyst combined amine based sorbent for direct air capture. This technology could be used in Minnesota to remove excessive carbon dioxide from the environment, remediating the effects of carbon dioxide in air and the resulting damages to the ecology and human health.

Impact: If succeed, this proposed novel technology will lead into more compact capture units due to the enhanced reaction kinetics and lead to an open door to the second stage of the project: converting CO2 to fossil fuel replacement energy such as ethanol, and butanol. In addition, it can provide a near zero emissions CO2 capture system if the solar energy is integrated in this DAC and conversion scaled up plant. The laboratory-scale proof of concept can then be easily scaled up due to the compact size of the system and its cost-effectiveness. If the proposed technology is successfully demonstrated on a large scale, there is the promise for investments (from both the public and private sectors) for further scale-up and validation that brings us one step closer to achieving negative carbon emissions, while potentially influencing carbon emission policies in both the state of Minnesota and the U.S. The results of this project will also be published in high-quality, peer-reviewed journals. 

Plant-Microbe Interactions to Phytoremediate Arsenic Contaminated Soils

Primary Investigator: Peter Kang
Co-investigators: Josh Feinberg, Michael Chen, and Sang Lee
Industry Partners: Bay West, LLC

Problem: Soil and groundwater systems, as well as many engineered remediation systems, are controlled by porous media flow. Naturally occurring biofilms often clog these systems, reducing flow rates and lowering the overall performance of a remediation system. Conversely, biofilms can consume contaminants, which may enhance existing remediation in a treatment system. To minimize clogging and fully exploit the bioremediation potential of biofilms, we need to better understand biofilms at a micro-scale within the filtration system itself.

Solution: A microfluidic visualization system can offer a better understanding of biofilms through direct observation of biofilm development in porous media. This new system will allow researchers to investigate the effects of fluid flow, water chemistry, and pore structure on the distribution and morphology of biofilms, as well as their subsequent impact on the overall remediation process. This knowledge can then be used to create optimal operating conditions for a system where bioclogging is minimized and bioremediation is maximized.

Impact: By balancing the detrimental and beneficial effects of biofilm formation in porous media, groundwater remediation system performance can be optimized. We will collaborate with the Science Museum of Minnesota to increase public awareness of bioremediation technologies, as well as the challenges associated with addressing groundwater contamination. This work will also support undergraduate internships that can facilitate entry into the workforce after graduation.

Bacterial Release of Metals in the Environment

Principal Investigator: Claudia Schmidt-Dannert, Biochemistry, Molecular Biology, and Biophysics

Co-Investigators: Maureen Quin, Biochemistry, Molecular Biology, and Biophysics, Alptekin Aksan, Mechanical Engineering

Industrial Partner: Minnepura Technologies

This project is proposing to develop an advanced biocomposite material for the rapid, on-site sequestration and detoxification of heavy metals and organic pollutants via a sustainable bioremediation approach. This material will be adaptable to a range of remediation sites, including heavy metal (e.g. arsenic, cadmium, mercury) contaminated mine drainage streams typical in northern Minnesota, and agricultural soil treated with pesticides and fertilizers. Our material will be built from robust detoxifying “Biohubs” that will be encased in silica to create a stable, portable and reusable material for field-deployment in a range of mitigation systems (e.g. flow-through packed bed reactors, membrane reactors, stirred tank leach reactors). 

Kinetics of Biofilms for Treatment of Airborne Organic Pollutants

Primary Investigator: Ping Wang
Co-Investigators: Joshua Goering (Undergraduate Research Scholar)
Industry Partners: NA
Award Type: Undergraduate Research Scholar

Problem: Airborne organic pollutants present greatly concerned threats to both human health and the environment. Efficient and sustainable onsite treatments for air quality control against very diluted pollutants are highly desired, yet not well developed yet.

Solution: Biodegradation of airborne organic pollutants (volatile organic compounds) using carbon fiber-supported biofilms was recently proven efficient in our lab for air clean up against VOC pollutions, in that it can achieve complete degradation of the VOC with minimum energy requirement and in a safe and sustainable manner. The new process involves no bulk phase aqueous solutions, different from traditional biodegradation systems where large quantities of precious water is demanded. The reaction kinetics for such a gas-biofilm reaction system is a new subject to be explored, and will provide basic info for future development of such biofilms reactors. This project aims to establish fundamental kinetic data and analysis for such a biodegradation system.

Impact: The proposed kinetic studies are expected to establish theoretical basis for evaluation and design of biofilm reactors using nontraditional gaseous substrates. Such reactors, easy to operate and can be applied in a sustainable pattern at adjustable scales for air pollution treatment against VOC emission, protecting both human health and the environment.

Using Fungus to Remediate “Forever Chemicals”

Primary Investigator:  Jiwei Zhang
Co-Investigators: Cara Santelli, Jerry Cohen, Charles Ayers (Graduate Research Scholar)
Industry Partners: SKB Environmental, Wenck-Stantec
Award Type: Seed Grant – Graduate Research Scholar (with NRRI Travel Grant)

ProblemPFAS are persistent and ubiquitous environmental contaminants, and these “Forever chemicals” are amongst Minnesota’s and the world’s greatest environmental challenges. Novel and efficient remediation technologies are needed to address the problem. Bioremediation would be an attractive alternative to physio-chemical methods that are often impractical on the scale required. Despite initial successes in PFAS degradation by microbes, the mechanisms of this degradation are not yet fully understood, particularly for fungi, hindering the development of relevant bioremediation technologies.

Solution: Fungi are an attractive option for the development of biological treatment for PFAS, namely “mycoremediation”. Leveraging the Zhang lab’s expertise in fungal biology with collaborators’ expertise in bioremediation and metabolite chemistry will allow for the development of a fungal platform to concurrently develop a bioremediation application for PFAS. This interdisciplinary collaboration will also allow for elucidating the genetic and chemical pathways of fungal PFAS degradation, providing the basic information required to develop effective mycoremediation technologies.

ImpactOur work will advance the bioremediation research of PFAS and, directly, lead to the development of a fungal method for PFAS leachate control in landfills. This will facilitate industries and environmental managers to meet the goal set in Minnesota’s PFAS Blueprint, sustaining the local environments and economies. We also envision the fungal degradation of PFAS can have even broader applications in other relevant contaminated fields.

Selective Biomining Using Bacteria

Primary Investigator: Jeffrey Gralnick
Co-Investigators: NA
Industry Partners: North Star Manganese Inc.
Award Type: Seed Grant – Postdoctoral Research Scholar

ProblemDue to increasing demands for manganese alloys and rare metals, there is a need to concentrate and recover minerals from low-grade ores, waste rock, and tailings. Many deposits in Minnesota contain mixtures of manganese and iron that represent valuable resources if their constituent metals can be separated. However, hydrometallurgical and pyrometallurgical processes with high energy inputs are unprofitable with these ores, and most microbial bioleaching approaches rely on sulfur release that is undesirable in Minnesota. New, green technologies are needed to passively extract specific metals and separate them for easy downstream purification without sulfate or acid production.

Solution: This proposal describes a new approach where bacteria self-control redox potential without external input, to reductively solubilize specific metals while avoiding production of environmentally harmful products.

Impact: Manganese ore found in Minnesota is commonly contaminated with iron and other metals that have significant economic value. We hypothesize that organisms with built-in redox control can separate these metals.

Biological Remediation of Adhesives

Primary Investigator: Steve Severtson
Co-Investigators: Jiwei Zhang
Industry Partners: H.B. Fuller Company
Award Type: Seed Grant – Postdoctoral Research Scholar

ProblemCompostability without sacrificing functionality is the requirement for the next generation of disposable adhesive products. Although sustainability considerations now play a major role in new adhesive designs, resources and guidance for companies looking to develop more sustainable commercial products are mostly absent. 

Solution: The research proposed herein aims to identify technology and approaches to close the life-cycle loop on PSA, PS labels, and other related consumer products. The project emphasizes water based PSA, which accounts for most of the disposable PSA market. We will work with industrial partners to integrate PSA product design and fungal degradation to enable the engineering of the entire life cycle of pressure-sensitive (PS) products. 

ImpactA number of Minnesota companies produce, coat or use PSA. It is a product whose market steadily increases 5% annually and is expected grow to nearly 13 billion dollars by 2025. This growth is due in large part to the expanding use of labels for applications such as mailing and shipping. In 2021, the United States will manufacture about 20 billion square meters of PS label products worth more than 15 billion dollars and containing more than 300 million dry pounds of PSA. Such products are manufactured, converted, sold, and, ultimately, discarded. The research proposed herein aims to identify technology and approaches to close the life-cycle loop on PSA, PS labels, and other related consumer products. 

Biofiltration of N2O

Primary Investigator: Satoshi Ishii
Co-Investigators: NA
Industry Partners: 3M Corporation
Award Type: Seed Grant – Postdoctoral Research Scholar (with NRRI Travel Grant)

ProblemA large quantity of greenhouse gas N2O is produced by human activities. The chemical decomposition of N2O is too energy-intensive, and therefore, alternative low-cost technology is needed. 

Solution: The proposed research will use bacteria to remove N2O from the air. Aerobic N2O-reducing bacteria identified in the Ishii lab can reduce N2O in ambient conditions, while the industry partner (3M) has highly efficient gas transfer membrane technology. By combining the U of M and the 3M’s technologies, this project will develop a highly efficient N2O-removing biofilter. 

ImpactThe goal of this project is to develop and optimize the biofilter that can remove >99% of the environmentally relevant N2O concentrations. The proposed research should contribute to reducing greenhouse gas N2O from the air with less cost. The proposed biofilter is designed to be easily scaled up; therefore, the biofilters should enhance the opportunities for industries in Minnesota. 

Microbial Conversion of Plastic Waste

Primary Investigator: Boya Xiong
Co-Investigators: Sebastian Behrens
Industry Partners: Ramsey/Washington County Recycling and Energy Team
Award Type: Seed Grant – Postdoctoral Research Scholar

ProblemSingle-use plastic or Polyethylene (PE) is the dominant plastic in the world, at 30% of the total global plastic market. Single-use plastic is a significant contributor to the solid waste stream and production forecasts indicated continued growth over the next few years. PE is the third most abundant form of plastic waste in Minnesota landfills and contributes to the increasing prevalence of nano/microplastics in local and regional waterbodies. PE plastics are both largely non-biodegradable and non-recyclable, and will continue to pollute the environment without a sustainable management plan.

Solution: Recent findings on the biodegradation of PE’s show the potential to biologically recover energy within densely packed PE structures. MnDRIVE researchers recently discovered a consortium of fungus and bacteria in Minnesota that can degrade and utilize PE as their sole carbon source. Dr. Xiong’s Lab will build on this early finding to develop a novel co-treatment process to enhance the microbial conversion of PE into value-added intermediates and energy. By enhancing the degradation of densely packed PE structures, this treatment process will enable the bioconversion rate to meet industry demands. 

Impact: The creation and implementation of this technology could completely alter the current, linear material flow of PE. The transition to a circular flow, where the use of PE products no longer signifies the end of its life, could stimulate and incentivize the collection and separation of such waste. A circular material flow for PE would drastically reduce the negative impacts of plastic waste accumulation. If successful, the product could be integrated with anaerobic microbial degradation and the accompanied production of biohydrogen and/or biomethane.

Can Mining Waste Help Remove Sulfide from Water?

Primary Investigator: Lee Penn
Co-Investigators: Alon McCormick, Spencer Bingham (Graduate Scholar)
Industry Partners: Barr Engineering; Minnesota Pollution Control Agency; Natural Resources Research Institute
Award Type: Seed Grant – Graduate Research Scholar

Problem: In Minnesota, excess sulfate in surface water is harmful to wild rice ecosystems. Current remediation techniques transform excess sulfate to sulfide using naturally occurring microbes. Still, the sulfide produced by microbes must be removed from the wastewater before it can be discharged, creating the need for novel sulfide removal methods.

Solution: The Penn Lab will use iron mining waste materials to remove the sulfide from water and produce iron sulfide solids. MnDRIVE researchers will optimize the conditions of iron sulfides formation to favor more stable products. The stability of the product iron sulfide must be optimized to minimize release of sulfur-species into the environment.

Impact: The ability to remediate sulfide from wastewater by producing stable forms of iron sulfide will prevent release of sulfur species into fresh water sources. Using waste from iron mining activities would employ materials that otherwise have little economic value. Results from MnDRIVE researchers will lead to improved safety in the management of sulfide and create economically useful materials.

Using Fungi to Decontaminate and Repurpose Wasted Lumber Products

Primary Investigator: Jiwei Zhang
Co-Investigators: Ulrike Tschirner, Shri Ramaswamy, Luke Heffernan (Undergraduate Scholar)
Industry Partners: PotlatchDeltic Bemidji Lumber; Andersen Windows and Doors
Award Type: Seed Grant – Undergraduate Research Scholar

Problem: When treated lumber ends up in landfills, harmful chemical preservatives can be leached into nearby groundwater and soil. Despite EPA banning many of these commonly used wood preservatives, products such as Copper Chromium Arsenic (CCA) and creosote continue to generate environmental issues. Moreover, waste lumber is also considered a reusable biomass resource that could provide an additional revenue stream, if harmful chemicals can be  properly removed.

Solution: The Zhang Lab will collect samples from landfills that stack lumber waste and test for the presence of fungi. The team will then examine identified fungi and assess their tolerance to CCA and creosote, as a first step in determining a possible method for decontaminating lumber waste. Additionally, the fungi will be assessed for their ability to decompose wood, also part of the process in creating a source of biomass to be used for bioproducts.

Impact: Identification of fungal species from sources of wasted lumber products could provide new methods of chemical remediation – ultimately preventing CCA and creosote from leaking into wastewater and soil. The use of fungus in remediating waste wood biomass would enhance the potential new revenue stream for chemical-free biomass and bioproducts.

Using Native Minnesotan Plants to Remove Heavy Metals from Contaminated Waters

Primary Investigator: Steven Sternberg, Chemical Engineering, UMD
Co-Investigators: Elayna Meyer (Undergraduate Scholar)
Industry Partners
Award Type: Seed Grant – Undergraduate Research Scholar

Problem: Mining operations in northern Minnesota demand new methods for removal of heavy metals from wastewater. Mining facilities release heavy metals at low concentrations but remain highly toxic to local ecosystems and have the potential to increase in concentration as they are incorporated into food chains.

Solution: MnDRIVE researchers in the Sternberg Lab will test the ability of duckweed, a native Minnesotan plant, to remove three different heavy metals from water. The team will test copper, nickel, and lead at varying concentrations along with anions that commonly associate with the heavy metals: chloride, nitrate, and sulfate. Researchers will use duckweed and water in a lab setting and analyze for changes to biomass, plant health, water quality, and more after exposure to heavy metals and anions.

Impact: Using a native Minnesotan plant to remove heavy metals from water surrounding mining operations would create a natural method of remediation. A successful remediation process would support the health of local ecosystems and prevent heavy metals from being incorporated into food chains.

Metal-Filtering Microbes

Primary Investigator: Cara Santelli
Co-Investigators: Tingying Xu (Postdoctoral Scholar)
Industry PartnersClearWater BioLogic
Award Type: Seed Grant – Postdoctoral Research Scholar 

Problem: A variety of metals mined in northern Minnesota are commonly used in the electronics, communications, and energy industries. However, mining occurs at a cost. High concentrations of metals in surrounding soils and waters can result from improper management of facilities and the mishandling of waste materials, posing significant risk to ecosystems and human health. Currently, few options exist for effective remediation of heavy metal contaminated waters.

Solution: Research shows that bioremediation of metal-laden water using microbial communities as a natural filtration system is effective. Specific Manganese-oxidizing “Mn-oxidizing” microbes act to remove Mn from metal rich fluids through natural redox reactions. Under the right conditions (e.g., pH), these reactions form Mn-oxide minerals that incorporate or adsorb the other metals. This moves manganese and metals from the liquid to solid phase and effectively lowers metal concentrations within the fluid. This project will investigate Mn-oxidizing microbes and their use in a bioremediation system to determine the capacity of this microbial system to simultaneously capture and remove other metals (Cobalt, Copper, Nickel) along with Mn from mining wastewater.

Impact: This research holds potential implications for both Minnesota and the mining industry at large. Development of an effective and low-cost bioremediation system to treat the heavy metal impaired waters of northern MN would provide significant ecosystem benefits. At the same time, Mn-oxidizing microbes offer a unique and valuable technology, if metals captured and enriched by the biominerals are selectively recoverable for downstream applications.

Leveraging Nano-Fluids to Improve Carbon-Capture Methods

Principal Investigator: Sam Toan
Co-Investigators: Richard Davis, Weiguo Xie, and Ye Wu
Industry Partner: Minnesota Power
Award Type: Seed Grant – Postdoctoral Research Scholar

Problem: Over 80 percent of the world’s electricity is produced from fossil fuels, which account for 25 percent of all carbon dioxide (CO2) emissions. New carbon-capture methods are needed for energy production sites, like Minnesota Power’s Boswell Energy Center, to address climate change concerns and meet Minnesota’s greenhouse gas reduction goals.

Solution: Nano-fluids, or fluids that have nanometer sized particles added to them, are known for their ability to make chemical reactions occur more easily, faster, and with greater efficiency. Prior investigation of nano-fluids has demonstrated their ability to improve the ease and efficiency of CO2 absorption and desorption reactions, thereby offering reduced net energy consumption for carbon-capture methods, possibly to zero. The proposed work will evaluate the effectiveness and cost-reduction possibilities through the use of flue gas samples collected from a coal-burning power plant in Cohasset, Minnesota. The investigation will enhance understanding of the kinetic and thermodynamic principles of nano-fluid CO2 capture.

Impact: The use of nano-fluids at the industrial-scale may be able to capture more CO2 and use less energy than traditional carbon-capture methods. Reducing energy requirements would also reduce the overall cost of implementing nano-fluid carbon-capture technologies. The proposed study could also lead to the use of nano-fluids to capture additional emission pollutants like SO2 and H2S.

Understanding How Bacteria Detoxify Harmful, Aromatic Chemicals

Principal Investigator: Kathryn Fixen
Co-Investigators: Jack Reddan (Undergraduate Scholar)
Award Type: Seed Grant – Undergraduate Research Scholar

ProblemMany industrial processes, like gasoline production, release toxic, aromatic (ring-structured) chemical compounds into Minnesota’s groundwater. Some bacteria, like Rhodopseudomonas palustris, are capable of degrading toxic, aromatic rings through the benzoyl-CoA pathway. However, the full chemical process of detoxification is not well understood, thus limiting the ability to utilize bacteria to remediate certain chemicals from the environment.

Solution: In order to degrade aromatic compounds, bacteria must reduce, or add electrons to, benzoyl-CoA. The electrons are supplied to benzoyl-CoA by a different molecule called BadB. It is not clear where BadB and the electrons it supplies to the benzoyl-CoA pathway originate from. In other model bacteria, the enzyme 2-oxoglutarate:ferredoxin oxidoreductase, encoded by the genes korAB, is known to supply electrons to BadB molecules. To see if this also holds true for R. palustris, the Fixen Lab will genetically modify multiple R. palustris strains by deleting the korAB genes and will observe changes in the ability to degrade aromatic rings. 

Impact: The benzoyl-CoA pathway in R. palustris will be better defined through observing bacterial growth and detoxification without the korAB genes. The detoxification of aromatic chemicals already happens naturally on a global scale, but a better understanding of how the benzoyl-CoA pathway in R. palustris will allow bacteria to be used in novel remediation systems that optimize their detoxifying abilities.

Can Algal Growth Prevent Pollution from the Duluth Complex?

Primary Investigator: Joshua Feinberg
Co-Investigators: Dan Jones, Jake Bailey, Kathryn Hobart (PhD Student), ZhaaZhaawaanong Greensky (Undergraduate Scholar)
Industry Partners:  
Award Type: Seed Grant – Undergraduate Research Scholar

Problem: The Duluth Complex rocks of northern Minnesota contain mineral resources such as copper, nickel, and platinum that are valuable to the state and global economy. However, these minerals are found in sulfide bearing rocks. Although natural oxidation of sulfide in mine waste occurs, rapidly enhanced rates of oxidation have been tied to the presence of certain microbial communities in these tailings. This enhanced oxidation results in elevated levels of sulfate and acid being input to the surrounding environment. These environmental contaminants are particularly detrimental to the culturally significant local wild rice populations.

Solution: Prior work has demonstrated that specific microbial species are responsible for enhanced sulfide oxidation of mining waste. One promising mitigation step towards decreasing sulfide oxidation rates is “bio-shrouding”, where sulfide ore is coated with organic material to prevent interaction between microbes and sulfide. Coating mine waste with organic compounds also promotes the growth of microbes that do not actively utilize sulfide, like algae. This creates a further physical barrier between the microbes that oxidize sulfide and the sulfide itself. The Feinberg team researched whether algal growth can be maintained on the surface of materials directly extracted from the Duluth Complex rocks. We found that algal growth on synthetic tailings may impede the growth of sulfide-oxidizing microorganisms and result in diminished sulfate release, but further study is required to determine if this effect scales in an industrially-useful way.

Impact: Contamination from sulfide-hosted mineral mining has the potential to significantly impact the economy of northern Minnesota and the entire state. However, the environmental consequences should not be ignored or overlooked. The predicted impact on ecosystems, particularly those hosting indigenous wild rice, can be positive if solutions like this prove to be sustainable and effective. Undergraduate ZhaaZhaawaanong Greensky received the 2018 SACNAS Student Presentation Award for her presentation on this research project (Society for Advancement of Chicanos/Hispanics and Native Americans in Science).

Using Nanocarbons to Trap and Remediate Air Pollutants

Primary Investigator: Ping Wang 
Co-Investigators: Benjamin Frigo, Chao Xu (Graduate Scholar)
Industry Partners:  3M
Award Type: Seed Grant – Graduate Research Scholar

ProblemMinnesota is home to a large community of ag/food, pharmaceutical, and other manufacturing companies. Many of these manufacturing facilities contribute significant amounts of volatile organic compounds “VOCs” into the atmosphere, as a by-product of their operations. VOCs are hazardous to human and environmental health and are actively monitored by the Minnesota Pollution Control Agency. However, few if any effective measures exist for mitigation of these airborne contaminants, especially at high concentrations.

Solution: When placed within air filtration systems, specific microbes are capable of degrading VOCs, although their effectiveness is limited by the concentration and flux of VOCs through the filter. In other words, the contaminant needs to be present at higher levels so that the microbial community can thrive. Engineered nanocarbon matrices (envision microscopic nets) offer a high surface area structure that enhances accumulation and concentration of VOCs as interaction occurs. The Wang Lab will construct a bioreactor using nanocarbon matrices that will be used to investigate remediation of VOCs contaminated air. The nanocarbon matrix will host biofilms that degrade VOCs, and the system will be analyzed for optimization.

Impact: Development of VOC treatment systems that are based on microbial remediation of contaminated air, would offer significant advancement of this technology. The success of this technology would provide many regional industry organizations a new potential solution in treating VOC emissions. Adoption of such technologies could reduce VOC emissions significantly.

A New Approach to Understanding Plastic-Eating Microbes

Primary Investigator: Brett Barney
Co-Investigators: Bo Hu, Natalia Calixto Mancipe (Graduate Scholar)
Industry PartnersDow Chemical Company
Award Type: Seed Grant – Graduate Student Research

ProblemPlastics in our environment are detrimental to ecosystems. However, we know little about the capacity or efficiency of microbes to degrade these plastics. Are specific microbial communities more efficient than other communities, based on environmental conditions or composition of the plastic?

Solution: Recently, researchers discovered and isolated individual strains of bacteria capable of degrading petroleum-derived plastics. These strains, however, have not yet been studied under community conditions. Professor Barney’s team will evaluate and characterize the ability of entire bacterial and fungal communities to digest common plastics. To do so, the team will build four lab-scale anaerobic digesters to test plastic degradation of different microbial communities under varying conditions. 

Impact: Development of an anaerobic plastic digester and a better understanding of the most effective microbial communities for degradation of plastics would offer a real and potentially scalable solution to the growing abundance of plastic in our environment. Studying microbial performance in a community-based setting should provide valuable insight on characterization under varying conditions, and ultimately the optimization of this remediation solution.

Chromium Removal From Industrial Stormwater Using Peat

Primary InvestigatorBrandy Toner
Co-Investigators: Cody Sheik and Brandy Stewart (Postdoctoral Scholar)
Industry Partners: American Peat Technology, Diamond Chrome Plating Inc., and Global Minerals Engineering, LLC.
Award Type: Seed Grant – Postdoctoral Research Scholar

Problem: Industrial stormwater can require expensive treatment to remove environmentally hazardous materials including heavy metal contaminants. Businesses continually look for cheaper and more efficient treatment products to meet their needs.

Solution: Peat-based systems surpassed initial expectations, especially in removing chromium (Cr) from stormwater. Yet, we know little about why peat is so effective. Toner’s team will analyze both the microbial communities and chemical state of chromium in peat filtration systems operating at Diamond Chrome Plating’s Michigan facility. Their analysis will shed light on the role microbial communities and chemistry play in Cr filtration in order to maximize the efficiency of the treatment system at Diamond Chrome. 

Impact: Identifying the role of microbial communities within peat-based filters may help optimize new microbe-based filtration systems. High efficiency, low-cost, and low-maintenance filtration systems targeting chromium and other heavy metals would be valuable across Minnesota given the abundance of heavy metal contaminated waterways throughout the state.

Stormwater Biofiltration for Duluth-Based Foundry

Primary Investigator: Steve Sternberg
Co-Investigators: Chan Lan Chun, Kristofer Isaacson (Graduate Scholar)
Industry Partners: ME Elecmetal, American Peat Technology
Award Type: Seed Grant – Graduate Research Scholar

ProblemStormwater runoff is recognized as the leading cause of water quality issues nationwide. Here in Minnesota, and specifically, in communities reliant on mineral extraction and manufacturing, stormwater runoff often mobilizes heavy metal and other contaminants, which are detrimental to the ecosystem and human health. While passive bio-reactors are proven tools for treatment and remediation of stormwater, further investigation is required to fully understand which bio-based materials and microbial communities are best combined for the removal of specific contaminants of concern.

Solution: ME Elecmetal is a Duluth-based foundry producing heavy equipment that is also seeking new and effective ways of preventing the release of contaminants from their properties during stormwater events. They are teaming up with the University of Minnesota researchers to analyze and identify bio-materials (e.g., manure, compost, crushed stone, woodchips, and peat) that are effective at removing various contaminants, such as aluminum, copper, iron, zinc, phosphorus, nitrogen, and sulfate from stormwater. The project will collect stormwater samples from ME Elecmetal’s Duluth site and analyze them in different bioreactor systems to determine which bio-based media + microbe + environmental/flow conditions provide an adequate remediation system under multiple conditions.  

Impact: In addition to furthering our understanding of bio-based stormwater treatment technologies, this project will provide specific analysis and insight on the optimized treatment system and remediation approach for a whole category of facilities similar to ME Elecmetal. Once identified, the highest-performing treatment option could be added as a layer underneath permeable pavement or built into retention pond walls. This would not only improve passive heavy metal removal in stormwater at ME Elecmetal’s site, but potentially at numerous other facilities.

Using Biological Oxidation of Sulfide to Protect the Mesabi Iron Range

Primary Investigator:  Jake Bailey
Co-Investigators: Daniel Jones
Industry Partners: Clearwater Layline LLC
Award Type: Seed Grant – Postdoctoral Research Scholar 

ProblemMining operations on the Mesabi Iron Range can elevate sulfate levels in surrounding waters, which is detrimental to wild rice. Minnesota’s strict sulfate limits put technical and economic strain on mining operations and municipal water treatment plants that discharge into wild rice waters. Standard biological sulfate treatment utilizes anaerobic microorganisms to convert sulfate to sulfide. The sulfide is then removed by adding iron, which results in the production of solid iron sulfide. The iron addition creates other environmental issues in sulfate treatment systems, such as low pH and elevated Cl in the effluent.

Solution: Biological oxidation of sulfide, a process that uses microbes to remove sulfide from water, could replace iron addition and produce elemental sulfur (S0) as a valuable end product to be sold to other industrial processes. The Bailey Lab will investigate microbial communities and conditions that promote consistent and predictable Sproduction. Using lab-scale bioreactors to simulate field conditions, they will optimize the biological oxidation process to ultimately test at pilot- or field-scale.

Impact: Maintaining low sulfate concentrations is important for Ojibwe communities in Minnesota, who rely on wild rice, or manoomin, as a culturally, economically, and spiritually important plant. Biological oxidation of sulfide to S0 could help mining companies in northern Minnesota remove sulfate with a more cost-effective, environmentally friendly process. 

A New Approach to Improving Water Quality for the Midcontinent Rift

Primary Investigator: Joshua Feinberg
Co-Investigators: Daniel Jones (Co-PI)
Industry Partners: Kennecott Exploration Company/Rio Tinto
Award Type: Seed Grant – Graduate Research Scholar

ProblemThe Midcontinent Rift (MCR) in Minnesota may contain the planet’s largest undeveloped deposit of copper, nickel, and platinum group elements. Minnesota’s mining industry faces barriers to this important economic opportunity because of water quality concerns. Mining activities can release acidic, metal-rich drainage in the environmentally sensitive region of Northern Minnesota. Current technologies for treating mining drainage cannot be applied to mining within the MCR because sulfide minerals in the MCR are in a different form (pyrrhotite) than in other mines (pyrite).

Solution: Microbiological oxidation of metal sulfides in mining waters intensifies the generation of harmful acidic drainage. Most studies seeking to prevent microbial oxidation focus on the oxidation of pyrite rather than pyrrhotite. The Feinberg Lab will address the gap in knowledge about oxidation of pyrrhotite using mineralogical, microbiological, and geochemical techniques. The researchers will identify and quantify the mechanisms of microbial oxidation in the MCR to reduce acidic drainage.

Impact: Understanding the mechanisms of microbial oxidation of pyrrhotite will enable researchers to develop preventative measures that inhibit the acid-producing microbial process. This project hopes to balance the economic opportunities of mining in the MCR with the protection of the cherished aquatic environments of Northern Minnesota. 

Engineering Bacteria for Enhanced Bioaccumulation of Toxic Metals

Primary Investigator: Jeffrey Gralnick
Co-Investigators: Brittany Bennett, Peter Intile, and Kaitlyn Redford (Undergraduate Scholar)
Industry Partners: NA
Award Type: Seed Grant – Undergraduate Research Scholar

ProblemMining generates a large amount of economic activity in Minnesota but can have undesirable consequences such as the release of large amounts of heavy metals into the environment. At certain concentrations, heavy metals become toxic to living organisms. New remediation methods are necessary to reduce the environmental impact of an important industry. 

Solution: Shewanella spp. are a type of environmental bacteria commonly found in aquatic sediments with heavy metals like manganese, chromium, arsenate, and uranium. Unlike other bacteria, Shewanella spp. have metal ion transport proteins which allows them to utilize heavy metals. The Gralnick Lab will characterize a gene called SO_3966 in Shewanella oneidensis which is believed to encode a protein that imports heavy metals into the bacteria. MnDRIVE researchers will identify which types of heavy metals can be imported by the protein, how the protein activity varies along different metal concentrations, and if similar genes are present in other Shewanella spp. bacteria.

Impact: The Gralnick Lab will examine how overexpression of the SO_3966 gene impacts the ability of Shewanella oneidensis to remove heavy metals from the surrounding environment. Characterizing the SO_3966 gene will provide information for how the bacteria could be adapted to remove heavy metals from contaminated soils and waters.

Aerobic Bioremediation of Selenium in Industrial Wastewaters

Primary Investigator: Cara Santelli
Industry Partners: CH2M
Award Type: Seed Grant – Graduate Research Scholar

ProblemSelenium is a toxic element found in many industrial waste streams. Anaerobic bioremediation is used to reduce selenium to an insoluble form that is filtered out before releasing the waste stream to the environment. However, these anaerobic conditions sometimes necessitate further treatment and cannot be used on all waste streams. 

SolutionAerobic bacteria and fungi are known to also reduce selenium to insoluble forms but are thus far not used in selenium bioremediation. Dr. Cara Santelli seeks to develop and optimize an aerobic bioremediation system to circumvent issues associated with anaerobic systems.

Impact: The development of an aerobic selenium bioremediation system will alleviate the complexities of anaerobic bioremediation for industrial wastewater treatment. The system may also be applied in northeastern Minnesota to treat groundwater with naturally elevated selenium levels and discharge from proposed mining operations that may exceed selenium limits.

Engineered Biochars for Sulfate Removal from Mining Waters

Primary Investigator: Sebastian Behrens
Kurt Spokas
Industry Partners: American Peat Technology; Global Mineral Engineering; Minnesota Department of Natural Resources
Award Type: Seed Grant – Postdoctoral Research Scholar

ProblemMining operations in Northeastern Minnesota, and particularly copper-nickel and iron mineral mining, discharge water to the surrounding environment with high sulfate and heavy metal concentrations. Given the unique positioning within the regional hydrologic system, this contaminated water threatens the ecosystems of the Mississippi River, Lake Superior, and Rainy River watersheds. Prior research has shown high levels of sulfate and heavy metals to be toxic to plants and wildlife, such as wild rice and lake trout. With expanded mining operations proposed, it is critical that remediation technology and tools keep pace, and prevent these contaminants from entering Minnesota waterways.

SolutionThe Behrens Lab is developing a low-cost, biochar-based material that absorbs sulfate and heavy metals and removes them from water. Biochar is a plant-derived porous media that will be enriched with iron and manganese to enhance it’s adsorptive properties relative to these contaminants. The adsorptive performance of the biochar will be evaluated and compared to other commercially available sorptive media. The team will thus be able to assess the effectiveness and efficacy of this lower-cost option.

ImpactIron and manganese enriched biochar is a relatively simple and low-cost solution for removal of sulfate and heavy metals from water. Iron’s magnetic properties not only enhance removal of heavy metals, but also the potential for recovery of these valuable metals from the biochar media, contaminated soil or sediment. Removal of sulfate and heavy metals will also begin remediating the impacted waters that support a culturally and economically important wild rice “manoomin” industry in northern Minnesota.

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