Mines Repository (Colorado School of Mines)
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Accelerating electrolyte transport property measurements for beyond lithium-ion batteries
No full textIncludes bibliographical references.2025 Spring.In order to meet the United Nations sustainability goals, there must be advances in long-duration energy storage. Lithium-ion batteries are the predominate technology, but due to the high cost of lithium and long implementation duration, they are not currently an economically viable solution. Zinc is projected to have a lower implementation duration and cost than lithium-ion batteries and therefore represents a promising solution. The question then becomes, ”If zinc is a promising solution, why is it not already implemented?” The main challenge lies in the charging process. Current zinc battery technologies suffer from ion transport limitations that lead to dendrite formation during charging. These dendrites pose safety risks and hinder cycling stability because they can penetrate the separator and cause a short circuit. If zinc is to fulfill its promise, secondary cell zinc technology must be developed. Key to this, is identifying electrolytes with good transport properties. Currently there are separate tests to measure each transport property, and to measure all four transport properties at one concentration it takes over 3 days. This is a significant barrier to screening a wide array of electrolyte candidates and is the motivation for my research. I created a new method of measuring transport properties that reduces the time required from days to minutes. This method will enable quick screening of electrolytes to develop new battery technologies with the potential to revolutionize long-duration energy storage
Multi-scale evaluation of groundwater flow and metal sourcing to streams in the Bonita Peak mining district
No full textIncludes bibliographical references.2025 Spring.Hydrologic and geochemical processes associated with acid mine drainage that result in the weathering of sulfide minerals and fluxes of metals to streams vary through space and time. Remediation of former mine sites relies on appropriate recognition and quantification of these changing processes. The need for both conceptual and quantitative understanding is particularly acute in headwater streams because these watersheds generate much of the water essential for ecosystem function and downstream human use, and headwater regions may be particularly sensitive to climatic changes. This research focuses on the Upper Animas River watershed in southwestern Colorado, a region substantially affected by historical mining over the past nearly 150 years to identify processes governing groundwater recharge and movement to streams, and associated metal weathering and fluxes, that operate over orders of magnitude in spatial and temporal extent. The three primary conclusions of this research are 1) metals are sourced from weathering of mineral deposits at depth (>500 meters below ground surface) and are transported long distances (multiple kilometers) by deep groundwater flow paths that terminate at springs and draining mines; 2) groundwater flow paths were modified by emplacement of hydraulic bulkheads resulting in new mineral equilibrium controls within the subsurface and a net decrease in iron and zinc export from the watershed; and 3) the solute budget of streams is controlled by discharge and metal fluxes from multiple distinctive groundwater systems with unique geochemical compositions and timescales of response to climatic perturbations. These results illustrate that groundwater flow, groundwater/surface-water interactions, and metal fluxes vary over spatial extents ranging from meters to multiple kilometers and on timescales ranging from days to decades. Data collection and modeling approaches that account for dynamic systems over these ranges of spatial and temporal extent are necessary when studying mountain headwater regions
Planning, policies, and governance: the importance of strategy when it comes to climate finance for Small Island Developing States
No full textRamping up climate finance flows for adaptation is critical to addressing the irreversible impacts of climate change, but this alone will not be enough to protect Small Island Developing States (SIDS). Planning is crucial when making strategic choices for policies and programs for climate change adaptation, particularly in the face of constrained budgets. Climate change is a complex and multifaceted challenge that affects various sectors and all of society
The fastest path to strategic mineral security
No full textThe United States is facing a critical minerals emergency. Our national defense, semiconductor, heavy manufacturing, and advanced energy sectors all rely on mineral supply chains dominated by foreign sources. China controls much of the production and processing of key critical minerals and has already imposed export restrictions on materials essential to U.S. weapon systems and strategic industries (WSJ)
Set of quadrangle maps covering varying townships and ranges in Albany and Carbon counties, Wyoming
No full textMine report no. 1956.Includes 15 maps. Scale not given.Title supplied by cataloger
Production of renewable fuels and destruction of per- and polyfluoroalkyl substances (PFAS) from organic waste streams
No full textIncludes bibliographical references.2025 Spring.Increasing urbanization and industrialization have led to more waste within cities, creating new opportunities and challenges for wastewater treatment. One major opportunity is the potential to recover organic carbon and nutrients from aqueous waste streams to produce new fuels and chemicals, converting wastewater treatment plants into waste resource recovery facilities. Simultaneously, rising levels of per- and polyfluoroalkyl substances (PFAS) from domestic and industrial sources enter wastewater treatment plants, where a large portion of these toxic, persistent, and recalcitrant compounds (including PFOA and PFOS – two of the most regulated PFAS) sorb to wastewater residual solids (biosolids and sludge). This thesis describes two methods of valorizing organic carbon in wastewater, one of which simultaneously destroys PFAS.
In the first method, a wide variety of organic compounds found in wastewater are funneled into a single biopolymer using microbes. This biopolymer can be depolymerized to a single monomer (3-hydroxybutyric acid, 3HB), which can be upgraded to propylene. The work in chapter 2 highlights the vapor-phase dehydration and decarboxylation of 3HB over hydrothermally stable solid acid catalysts to form propylene, which can later be used to synthesize hydrocarbon fuels and industrial chemicals.
In the second method, PFAS is destroyed while energy and nutrients are recovered simultaneously from WWRSs by using hydrothermal liquefaction (HTL) in conjunction with a strong alkali (1–3 M NaOH) in a process known as hydrothermal alkaline treatment (HALT). The destruction of the most recalcitrant PFAS was found to depend on the ratio of applied NaOH to wt% of WWRS, with 20.10 molNaOH kg-1solids required to degrade PFSAs to non-detect levels within 1 h at 350°C; the extent of degradation increases with increasing reaction time and temperature. These results informed an open-source modeling platform (QSDsan) to characterize the economic and environmental sustainability of a treatment train employing HALT to upgrade WWRSs. In baseline HTL conditions without NaOH, the model predicts a sludge management cost of -54.80±63.37 ·tonne–1 at conditions using HALT that destroy >99% of PFSAs. The impact of PFAS regulations and energy policy on total treatment cost is also described
Geology and genesis of the Golddigger property, British Columbia, Canada
No full textIncludes bibliographical references.2025 Spring.The Golddigger property is located in the Golden Triangle of British Columbia, Canada. It comprises a series of polymetallic quartz-sulfide veins which cut deformed volcanic and sedimentary rocks as well as younger granitoid dikes. These veins are host to semi-massive to massive pyrrhotite, sphalerite, and galena with lesser pyrite, chalcopyrite, native gold, native silver, bismuth minerals, and silver sulfosalts. Using a combination of field work, petrographic observations, and microanalytical techniques, paragenetic relationships were determined to reconstruct the evolution of the hydrothermal system at the vein scale. It is demonstrated that the initial development of skarn mineral assemblages was followed by early quartz veining. The early quartz shows extensive evidence for recrystallization and was formed at lithostatic conditions. Its fluid inclusion inventory was affected by post-entrapment modification as pressures changed to hydrostatic conditions. Late quartz in the veins was formed as hydrostatic pressures were established. Fluid inclusion analysis demonstrates that primary and secondary inclusions in the late quartz did not experience post-entrapment modification. Vein formation occurred at >5-6 km below the paleosurface from hydrothermal fluids that contained high CO2 concentrations and were of low to intermediate salinities. Native gold and silver formed late in the paragenesis at Golddigger. Eocene ages obtained by U-Pb dating of zircons of igneous rocks, U-Pb dating of garnets which predate mineralization, and Re-Os dating of sulfides suggest that Golddigger may be linked to the Alice Arm intrusive suite, which is known to host porphyry Mo deposits including the Kitsault Mo porphyry. The findings of this study have significant implications to the metallogenic model of the Golden Triangle as a possible link between Eocene deep-seated intrusions, including those hosting porphyry Mo deposits, and polymetallic quartz-sulfide veins has not been previously invoked
Widening hydrograph spread with declines in snow across the western United States is modulated by sub-basin heterogeneity
No full textIncludes bibliographical references.2025 Spring.Mountain snowpacks are a critical source of water, supplying the majority of runoff in the western U.S. Seasonal snowpacks act as natural water towers, storing water during the winter and releasing it during the spring and summer when demand is highest. The quantity, timing, and distribution of streamflow throughout the water year all determine water availability for both ecosystems and human use. However, declining snow accumulation and shifting melt dynamics are changing hydrograph characteristics and affecting water availability in ways that are not yet fully understood. In particular, changes to the width of the streamflow distribution can affect water resource allocation, but have only been minimally investigated. This study investigates the relationship between snow water equivalent (SWE), streamflow center of timing (CT), and the width of the streamflow distribution, operationalized as the standard deviation of timing (SDoT) in snow-dominated basins across the western United States. Furthermore, I examine how hydrologic partitioning and spatially heterogenous responses to warming control SDoT and CT using the East River, CO as a case study basin. Using empirical analysis of gauged streamflow from 95 minimally disturbed basins and a spatially distributed SWE reanalysis product, I evaluate the relationship between SWE and SDoT, the role of basin climate in this relationship, and the performance of statistical models under different snow drought conditions. I then apply a physics-based hydrologic model to disentangle shifts in the distribution of individual runoff generation components with warming and assess how these changes are reflected in the channel. At 85% of gages across the western United States, low peak SWE is associated with a wider SDoT, with the strongest effect observed in basins with low precipitation. In the East River, a simulated 2ºC of warming induces changes in CT and SDoT for groundwater, interflow, and surface runoff, but interannual and spatial responses are highly variable. At the basin outlet, the channel exhibits less than one day change in SDoT. This stability results from opposing responses to warming: SDoT widens in the cases of surface water, interflow, and low elevation groundwater SDoT, but narrows for groundwater contributions from high elevation HRUs, which produce the majority of streamflow and counterbalance declining SDoT from other sources. Overall, results indicate that declining peak SWE may alter streamflow distributions and water availability, and that the degree of future impacts will depend on basin-specific hydrologic processes
Report on Queen of the Hills mine
No full textMine report no. 1736.Includes one plan of mine workings and five topographic quadrangle maps with dates ranging from 1950-1966