Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “sequestration”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51

M4SF-22LL010302052-Radionuclide Incorporation Model for Corrosion Products

This progress report (Level 4 Milestone Number M4SF-22LL010302052) summarizes research conducted at Lawrence Livermore National Laboratory (LLNL) within the Crystalline Activity Number SF-22LL01030205. The research is focused on actinide and radionuclide sequestration in steel corrosion products.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Capturing Carbonation: Understanding Kinetic Complexities through a New Era of Electron Microscopy

Cryogenic plasma focused ion beam (PFIB) electron microscopy analysis is applied to visualizing ex situ (surface industrial) and in situ (subsurface geologic) carbonation products, to advance understanding of carbonation kinetics. Ex situ carbonation is investigated using NIST fly ash standard #2689 exposed to aqueous sodium bicarbonate solutions for brief periods of time. In situ carbonation pathways are investigated using volcanic flood basalt samples from Schaef et al. (2010) exposed to aqueous CO 2 solutions by them. The fly ash reaction products at room temperature show small amounts of incipient carbonation, with calcite apparently forming via surface nucleation. Reaction products at 75° C show beginning stages of an iron carbonate phase, e.g., siderite or ankerite, common phases in subsurface carbon sequestration environments. This may suggest an alternative to calcite in carbonation low calcium-bearing fly ashes. Flood basalt carbonation reactions show distinct zonation with high calcium and calcium-magnesium bearing zones alternating with high iron-bearing zones. The calcium-magnesium zones are notable with occurrence of localized pore space. Oscillatory zoning in carbonate minerals is distinctly associated with far-from-equilibrium conditions where local chemical environments fluctuate via a coupling of reaction with transport. The high porosity zones may reflect a precursor phase (e.g., aragonite) with higher molar volume that then “ripens” to the high-Mg calcite phase-plus-porosity. These observations reveal that carbonation can proceed with evolving local chemical environments, formation and disappearance of metastable phases, and evolving reactive surface areas. Together this work shows that future application of cryo-PFIB in carbonation studies would provide advanced understanding of kinetic mechanisms for optimizing industrial-scale and commercial-scale applications.

36 MATERIALS SCIENCE↗

Modeling Flow and Transport in Fractured Rock using Machine Learning [Slides]

Fractured systems in the subsurface play a role in many natural and engineered applications such as geologic carbon sequestration, hydraulic fracturing and underground nuclear test detection. Structural information (fracture size, orientation, etc.) plays a key role in governing the dominant physics for these systems but can only be known statistically. Traditional modeling approaches either ignore or idealize structural information at these larger scales because we lack a computational framework that utilizes it in its entirety. The work presented here integrates computational physics, machine learning and graph theory to make a paradigm shift from computationally intensive high-fidelity models to coarse-scale graphs without loss of critical structural information. We exploit the underlying discrete structure of fracture networks in systems considering flow through fractures and fracture propagation. We demonstrate that compact graph representations require significantly fewer degrees of freedom (dof) to capture micro-fracture information and further accelerate these models with Machine Learning.

58 GEOSCIENCES↗

Advanced Airfoil Cooling Schemes to Increase Efficiency in Gas Turbines for Combined Heat and Power Applications

This report describes a three-year interdisciplinary effort funded by the U.S. Department of Energy’s (DOE) Energy Efficiency and Renewable Energy/Advanced Manufacturing Office (EERE/AMO) to promote market penetration of combined heat and power (CHP) technologies. Prior studies have shown the technical potential for CHP in the United States is much larger than the current deployment of CHP systems. A large portion of the technical potential CHP market aligns with small (<20 MWe) gas turbines. CHP systems are an attractive alternative to reduce greenhouse gas (GHG) emissions. For example, CHP systems can reduce GHG emissions by 30–40% relative to a conventional boiler and power configuration. These GHG emission reductions are “avoided emissions” which means no CO 2 separation or sequestration is required. This report describes an effort to use additive manufacturing (AM) technologies and advanced airfoil cooling designs to increase the turbine inlet temperature by 100 °C for small gas turbines typically used in CHP systems. At the beginning of this effort, baseline performance data for small gas turbines was not available, and the potential benefits of cooling system improvements were not quantified in the available literature.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Initial Risk Inventory for Commercial Scale Storage Sites

The “Southeast Regional CO 2 Utilization and Storage Acceleration Partnership” (SECARB-USA) project supports the U.S. Department of Energy (DOE) Office of Fossil Energy's (FE) mission to help the United States meet its need for secure, affordable, and environmentally sound fossil energy supplies by utilizing the advancements made since 2003 by the Regional Carbon Sequestration Partnership (RCSP) Initiative to continue to identify and address knowledge gaps. The SECARB-USA regional initiative encompasses the states of Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, and portions of Kentucky, Missouri, Oklahoma, Texas, and West Virginia. The primary objective of the project is to identify and address regional onshore storage and transport challenges facing commercial deployment of carbon dioxide (CO 2 ) capture, utilization, and storage (CCUS) technologies. This document provides an overview of risks relevant to commercial CCUS projects.

01 COAL, LIGNITE, AND PEAT↗

LH CO 2 MENT Colorado Project (Final Report)

The objective of Electricore’s pre-FEED project “LH CO 2 MENT COLORADO PROJECT” is to accelerate the implementation of a 1.5 million tonnes per year (TPY), and first-of-a-kind (FOAK) at world scale, Svante VeloxoTherm™ carbon capture plant. This project represents a quantum leap to a large-scale facility that will launch Svante’s carbon capture technology into the next era of accomplishments and market acceptance. By completing the Front-End Loading (FEL) Feasibility Study Report (FEL-2) for a fit-for-purpose design at the HOLCIM cement plant, located near Florence Colorado, USA, this technology can be proven as the future of large-scale deployment for carbon capture and storage. This carbon capture plant was designed with the goal of reaching a target of near Net Zero Emissions by capturing 90% of the carbon dioxide (CO 2 ) emissions from the HOLCIM cement plant and from the boiler which produces steam required to regenerate the adsorbent. Additionally, this project will be leveraging a renewable Power Purchase Agreement (PPA) using solar energy to acquire power at the target price of 0.04 $/kWh or less. In its current configuration CO 2 emissions from the HOLCIM cement plant is around 700 – 800 kg/ton of clinker produced. The proposed new carbon capture plant will allow a reduction of CO 2 emissions to about 100 kg/ton of clinker produced. The scope of work consists of the process design and capital & operating cost estimation (Class IV) for a total plant capacity of 4,750 TPD of pipeline grade CO 2 . The Svante VeloxoTherm™ technology is comprised of a Rotary Adsorption Machine (RAM) for intensified Thermal Swing Adsorption (TSA) using Structured Adsorbent Beds (SABs) and related Balance of Plant (BOP), including CO 2 compression. A business case (financial analysis) evaluation has been undertaken for the Owner’s management review. Recommendations on how best to proceed to the next stage of the project have been conveyed and are documented within this report. This analysis has relied on a detailed and comprehensive Project Financial Model, evaluating the Total Project IRR (after tax, unlevered, and including all forecast 45Q PTCs and 100% tax efficiency) – the project financial analysis (as opposed to standard TEA analysis) only considered a 12 year plant economic lifetime as a result of 45Q being the sole driver considered at this stage. The Total Project IRR was evaluated across a large number of potential scenarios. The evaluation demonstrated that if the 45Q PTD is increased to $85/MT for sequestration, there are a large number of feasible scenarios which demonstrate economic returns.

01 COAL, LIGNITE, AND PEAT↗

Strategies for Achieving the DOE Hydrogen Shot Goal: Thermal Conversion Approaches

In July 2021 the United States (U.S.) Department of Energy (DOE) launched the first of a series of Department-wide Energy Earthshot goals designed to accelerate breakthroughs of more abundant, affordable, and reliable clean energy solutions within the decade. The Hydrogen Shot goal seeks to reduce the cost of clean hydrogen to $\$$1 per 1 kilogram in 1 decade ("1 1 1"). Today, thermal conversion of fossil fuels represents the predominant, lowest cost method of hydrogen production. In 2020 approximately 75 percent of global, dedicated hydrogen production was produced via fossil fuels using thermal conversion approaches such as steam reforming and gasification. However, carbon management techniques such as CO 2 capture and sequestration (CCS) and pyrolysis are not widely represented in the current fossil-based hydrogen production fleet. Lowering the cost of clean hydrogen production from commercial and advanced thermal conversion-based technologies is critical for successfully achieving the Hydrogen Shot goal. This report presents the findings from an initial screening analysis of several scenarios that explore cost drivers related to clean hydrogen production. The screening encompasses commercially available and developing thermal conversion technology alternatives as well as factors exogenous to the plant such as feedstock/byproduct pricing, CO 2 pipeline and storage infrastructure costs, and scale to assess potential pathways towards meeting the Hydrogen Shot goal. Additionally, this report presents initial Research and Development (R&D) strategies to advance thermal conversion technology towards meeting the Hydrogen Shot goal.

08 HYDROGEN↗

Improving Subsurface Stress Characterization for Carbon Dioxide Storage Projects by Incorporating Machine Learning Techniques

The overall objective of this project is to develop a framework for reliable characterization and prediction of the state of stress in the overburden and underburden (including the basement) in CO 2 storage reservoirs using machine learning and integrated geomechanics and geophysical methods. Specifically, we propose to develop workflow encompassing of technologies and/or methods to predict stress and pressure changes due to CO 2 injection in an active tertiary recovery site and their impacts on subtle fault activation, fractures and occurrence of microseismic events and compare responses to field observations. In this project, we anticipate using dataset from the Farnsworth field Unit (FWU) which is operated by Purdure Petroleum. A novel elastic-waveform VSP inversion technique will be used to estimate high-resolution spatial and temporal changes of elastic moduli in CO 2 storage reservoirs, which will be combined with velocity-stress relationship derived from laboratory tests to obtain subsurface pressure and stress. Clustered microseismic data will be jointly inverted for improved focal mechanisms. Least-squares reverse-time migration of microseismic waveform data will be performed to directly image fracture/fault zones. Additionally, a deep neural network machine learning technique with convolutional and recurrent layers will be used for learning the spectro-temporal structures in microseismic waveforms. The results of this geotechnical data analysis will be integrated to develop a high-resolution 3D mechanical earth model extending from the overburden sealing formations to the underburden including the basement. Mechanical properties will be derived through integration of mechanical logs, tests, available results from chemo-mechanical laboratory tests, and elastic inversion of seismic data using a combination of Bayesian and stochastic methods as well as machine learning technique. Failure features (faults/fractures) will be represented and/or modeled based on seismic and core data analysis. A transient hydrodynamic-geomechanical model will be developed through coupling with the calibrated FWU reservoir simulation model. The full physics coupled model will be used to train a reduced order proxy model using machine learning algorithm for estimating stress which will then be used with appropriate constitutive relationships and forward seismological models to simulate pressure changes and induced microseismicity. An advanced optimization framework will be developed to perform a history match to minimize error between field observations and simulated. The history matched proxy model will be verified against the full-physics equivalent. The field observations that will be used in the coupled model calibration process include pressure/stress inverted from VSP, moment magnitude from microseismic analysis, real time downhole pressure measurements, production and injection data. Parameter sensitivity and uncertainty analysis will be performed to characterize the impact of model parameter uncertainty on stress estimates. The proposed project will have significant impact on future field implementation of the proposed technology. Because the project field site is an ongoing CO 2 EOR development, the value of the new technology will be demonstrated in an operational context and evaluated as a viable risk mitigation strategy. Cost/benefit will be evaluated together with the various commercial incentives for CO 2 sequestration available to oil and gas operators. The extensive available dataset and ongoing data acquisition under the SWP Phase III work plan provides flexibility for investigation of multiple approaches and reduces technical risk.

58 GEOSCIENCES↗

Gasification of Coal and Biomass: The Route to Net-Negative-Carbon Power and Hydrogen

One promising process that is a candidate for meeting the goals of the US Department of Energy’s 21st Century Power Plant initiative is to gasify a mixture of coal and biomass to yield a syngas, which can have CO2 removed and then be used to produce hydrogen as well as an off-gas that can be used to flexibly produce power. This concept would overall be carbon net-negative and readily meet the 21st Century Power Plant initiative targets of smaller scale MW generation, high ramp rates and turndown, feedstock flexibility, and high efficiency—at a reasonable cost. Moreover, adding the large-scale production of “ultra-green” hydrogen yields a system tailored for the coming hydrogen economy, providing long-term energy storage and an attractive co-product for sale. The objective of the work being led by the Electric Power Research Institute, Inc. (EPRI), with support by Bechtel Corporation (Bechtel), Gas Technology Institute (GTI), Hamilton Mauer International, Inc. (HMI), Nebraska Public Power District (NPPD), NexantECA, Inc. (Nexant), and Wärtsilä, is to perform a front-end design and engineering (FEED) study on an oxygen-blown gasification system coupled with water-gas shift, pre-combustion CO2 capture, and pressure-swing adsorption working off a coal/biomass mix to yield high-purity hydrogen and a fuel off-gas that can generate power. Several designs are being considered that will be capable of producing 50 MW net from a flexible generator, over 8500 kg/hr of hydrogen, and net-negative CO2 emissions, at an efficiency of 50% net HHV. The plant would be hosted at an NPPD site, where opportunities for enhanced oil recovery and sequestration have been investigated and the need for low-carbon power and hydrogen is imminent. The principal biomass to be used is corn stover—prevalent in Nebraska where the plant will be located—mixed with Powder River Basin (PRB) coal, necessitating a gasifier that can use this feedstock and be flexible to allow other types. Waste plastics will also be reviewed for use. Two oxygen-blown gasifiers have been identified as candidates that have done testing with biomass including corn stover: the GTI gasifier—a high-pressure, fluidized-bed type—and HMI’s, a lower pressure moving-bed type. Both have relative advantages that were investigated in the Phase I design study, with a resultant down select of one system for which the FEED will be performed in Phase II. The technical tasks for the project are: • Design Development: Completion of design activities necessary to provide inputs for the FEED study. Multiple design cases will be assessed with the selection of the optimal one for the FEED. • Investment Case Preparation: Development of the draft investment case for the proposed process with business cases performed for the proposed host site and two other locations. • Host Site Selection: Evaluation of the two potential host sites within NPPD’s portfolio to select the preferred candidate based on technical, economic, and environmental considerations. • Environmental Information Volume (EIV) Development: Completion of the EIV for the host site. • FEED Study: Completion of a FEED study based on the design selected in Phase I. A Greenhouse Gas Life Cycle Analysis will also be performed for the process. • Update Investment Case: Finalization of the investment case based on findings from the FEED. The advantages of the proposed project are significant. Having an engaged U.S. power utility willing to provide a host site that will produce energy from coal plus a deep and experienced team is critical; the process meets all the goals of DOE’s 21st Century Power Plant initiative at an estimated total plant cost of ~$880M and a production cost of hydrogen of ~$2/kg-H2 while producing net-negative carbon power. If developed, this process has real commercial potential in the United States—supported by EPRI’s initial review of the considerable interest from selected U.S. utilities—and elsewhere around the globe. The process has fewer environmental hurdles compared to other concepts, lowering regulatory and protest risks—providing a pathway to preserving the viability of a critical indigenous energy source by transforming its use to match a changing world. This presentation outlines the motivation for the effort, summarizes project plans, work completed to date, results of the Phase I effort and, and detailed work scope for the remainder of the project in the Phase II FEED effort.

01 COAL, LIGNITE, AND PEAT↗

Integration of seismic-pressure-petrophysics inversion of continuous active-seismic monitoring data for monitoring and quantifying CO 2 plume (Final Report)

The overall objective of this project is to develop and validate an integrated package of joint seismic-pressure-petrophysics inversion (jSPPI) of continuous active-source seismic monitoring dataset capable of providing real-time monitoring of CO 2 plume during geologic carbon sequestration (GCS). The three specific developments include: (a) the methodologies for fast seismic full waveform inversion of continuous active source seismic monitoring, (CASSM) datasets for simultaneously estimating velocity and attenuation, and with data assimilation; (b) joint Bayesian petrophysical inversion of seismic models and pressure data for providing and updating CO 2 saturation models; (c) the methods using multiple datasets including (Crainfield and Frio-II borehole) synthetic, laboratory, and field CASSM datasets. The outcomes of jSPPI include (a) a workflow for processing CASSM data, (b) Bayesian inversion algorithms using CASSM data and pressure response data, and (c) integration with data assimilation algorithms for continuously updating site-specific models used for prediction and reservoir management. The validation of joint FWI will be conducted using synthetic models based on the Cranfield and Frio experiments as well as field CASSM datasets collected as part of the Frio-II pilot injection. To quantify and map the mass and distribution of CO 2 (saturation), we will jointly invert velocity and attenuation measurements from the FWI with a Bayesian approach using a rock physics model for attenuation (e.g., White’s attenuation model with two selected patch sizes (White, 1976; Dutta and Seriff, 1979)). The Bayesian inversion will be applied to each time step in the CASSM survey in an updating scheme, which integrates with an ensemble of reservoir simulations at each step. A more complete experimental validation dataset will be collected as part of a mesoscale (2-3 m) gas-CO 2 injection experiment utilizing a higher frequency version of the CASSM system developed for laboratory studies; the integrated inversion will be demonstrated using this dataset which will provide both a dense geometry as well as more precise secondary confirmation measurements (e.g. saturation) typically not available in the field. The resulting real-time map of CO 2 saturation is able to provide a deeper scientific understanding of the complex, time-varying dynamics of subsurface fluid flow migration path as well as the rapid detection of CO 2 leakage hazards.

25 ENERGY STORAGE↗

Blue Bison ATR Advanced CCUS System (Final Report)

The objective of this project was to design a carbon capture system that could be installed on a 220 MMSCFD blue hydrogen (Blue H 2 ) facility (Blue H 2 Plant) utilizing auto-thermal reforming (ATR) technology and identify potential sequestration options for the carbon dioxide (CO 2 ) produced from the Blue H 2 Plant.

08 HYDROGEN↗

Interrogating organo-mineral interactions by Py-GC/MS and ToF-SIMS

Soil organic matter (SOM) is crucial to soil fertility and agricultural sustainability in the face of climate change, and organo-mineral interactions are a key mechanism for stabilizing SOM. The stability of mineral-associated organic matter (MAOM) can be approximated by the strength of bonds between biomolecules and mineral surfaces. We hypothesized that factors such as mineral reactivity and solution pH would impact bonding strength. To test these factors, sorption isotherms were performed on minerals differing in particle size, morphology, and reactivity (quartz, goethite, gibbsite, kaolinite, montmorillonite), under two pH conditions (4 and 6), and across a range of tannic acid concentration (0-1400 ppm). The quantity and quality of organo-mineral bonds was assessed by quantifying post-sorption solution compounds using an absorbance plate reader and assessing the thermal energy needed to break bonds using evolved gas analysis (EGA) on a pyrolysis gas chromatograph-mass spectrometer (Py-GC/MS). Organo-mineral surfaces were also interrogated using Time-of-flight secondary ion mass spectrometry (ToF-SIMS). Sorption experiments revealed an asymptotic relationship between sorbed tannic acid and increasing initial concentrations which suggests our concentration range saturated available mineral surfaces. Results indicated that mineral identity, chiefly surface area and native pH, impacted the amount of compound sorbed to mineral surfaces. Evolved gas analyses of organo-mineral samples uncovered increased thermal stability of sorbed compounds compared to our tannic acid standard particularly on the iron oxide, goethite. ToF-SIMS revealed that goethite surface ions were covered by increasing concentrations of adsorbed tannic acid with the replacement of chlorine and sulfate ions by tannic acid related ions. Our results indicate that Py-GC/MS and ToF-SIMS are useful techniques to determine the nature and strength of organo-mineral bonds and are steppingstones to understanding controls on carbon sequestration in terrestrial systems.

58 GEOSCIENCES↗

Leveraging the bioeconomy for carbon drawdown

Stringent climate change mitigation scenarios rely on large-scale drawdown of carbon dioxide from the atmosphere. Amongst drawdown technologies, bioenergy with carbon capture and sequestration (BECCS) has received considerable attention in the climate mitigation literature. Recently, attention has shifted further from a relatively narrow focus on BECCS to a broader focus on Biomass Carbon Removal and Storage (BiCRS). The concept of BiCRS has the potential to enable a future where the climate mitigation value of biomass resources is more valuable than the energy value, due to the potential to remove and sequester large quantities atmospheric CO 2 . This article provides a qualitative overview of prominent BiCRS technologies from which a set of the most promising technologies are assessed quantitively through life cycle assessment. There are numerous opportunities to incorporate carbon removal and management within the bioeconomy, but the majority of immediate carbon removal potential exists in four bioproducts: bioenergy, bioplastics, biochar, and wood products. We analyze the life cycle greenhouse gas emissions and disposition of sequestered carbon over 10,000 years for four bioproducts representative of each broader category: an advanced BECCS pathway, biopolyethylene, oriented strand board, and biochar soil amendment. We find that the BECCS pathway has the greatest magnitude and durability of CO 2 storage over all time horizons. However, non-BECCS pathways achieve 34–64% of the drawdown magnitude relative to BECCS and retain 55–67% of their initial drawdown over 100 years (central estimate). We identify three engineering strategies for enhancing carbon drawdown: reducing biomass supply chain emissions, maximizing carbon stored in long lived products, and extending the term of carbon storage. Finally, we highlight the need to characterize both the magnitude and permanence of carbon drawdown as a means for policymakers and technology develo pers to deploy limited biomass resources to maximize mitigation benefits.

09 BIOMASS FUELS↗

Abstract for CRADA between NETL and MetroLaser, Inc. (AGMT-1363)

NETL and MetroLaser, Inc. (MetroLaser) will collaborate on the commercialization design and validation of a split laser system, useful for sensing and measurement applications relevant to fossil energy and carbon management in subsurface environments relevant to carbon sequestration.

42 ENGINEERING↗

Development of Laboratory Testbeds Simulating Real-World Greenhouse Gas Emissions

Climate change leads to drastic variations in the environment that can threaten food security. To protect the security and prosperity of the environment, new agricultural practices that mitigate greenhouse gas emissions need to be developed. Agriculture plays a large role in the emissions of greenhouse gases, thus a need for new practices. At present, testing landscape management practices for carbon sequestration and reduction of greenhouse gas emissions are expensive because such tests often require intricate field experiments. Laboratory tests on landscape management practices often fail to simulate and accurately represent the natural systems researchers intend to study. There are methods that can be used to make these laboratory tests more closely replicate natural systems for the improvement of agricultural lands used in biofuel and food production. The goal of this project is to develop a laboratory testbed replicating field conditions that will mimic field greenhouse gas emissions. To achieve this goal, we used soil cores taken from agricultural and marginal lands, then attached fiberglass wicks to improve the drainage system in the soil core to simulate a more natural hydraulic system. The soil cores with the wicks were used to compared to greenhouse gas emissions observed in the field. Our preliminary results suggest that the soil carbon dioxide and nitrous oxide flux from the agricultural land site were comparable to the soil cores equipped with the drainage wicks. The data suggests that laboratory testbeds can be used to mimic field greenhouse gas emissions if parameters, such as soil water content were in a set range. The laboratory testbed produces similar greenhouse gas emissions to the agricultural site when the soil water content was between 15-25%.

54 ENVIRONMENTAL SCIENCES↗

Radionuclide Interaction with Hydrothermally Altered Repository Materials (M4SF-23LL010302052)

This progress report (Level 4 Milestone Number M4SF-23LL010302052) summarizes research conducted at Lawrence Livermore National Laboratory (LLNL) within the Crystalline Activity Number SF-23LL01030205. The research is focused on actinide and radionuclide sequestration in hydrothermally altered repository materials. In FY23, a manuscript was in preparation for publication summarizing our analysis of radionuclide sorption and coprecipitation into Fe oxide phases and evaluation of radionuclide partitioning values across a range of radionuclides relevant to performance assessment. We demonstrated our approach in detail using Se sorption and coprecipitation with iron oxide minerals. These data were presented in our FY22 annual report and will not be repeated here. We also initiated experiments to identify radionuclide interaction with hydrothermally altered crystalline repository and backfill materials. Recent research performed at Los Alamos National Laboratory (LANL) and Sandia National Laboratory (SNL) has provided key insights regarding the hydrothermal alteration behavior of bentonite backfill in the presence of repository materials (steel, concrete, etc.). We are now examining how mineral alteration affects retardation behavior of plutonium and a suite of other radionuclides. These experiments also allow us to test the predictive ability of our component additivity approach to surface complexation and ion exchange. Our guiding hypothesis is that a robust surface complexation/ion exchange model and associated database, developed using our L-SCIE approach, can effectively predict changes in radionuclide sorption behavior resulting from the hydrothermal alteration of mineralogy in a repository near field. A short update of results to date is presented below. A manuscript was also in preparation describing a self-consistent model and approach to simulating Se(IV) and Se(VI) sorption to 5 iron oxide phases based on our L-SCIE community database. This will be the first implementation of a multi-mineral and multi-oxidation state sorption model using our new L-SCIE database and workflow. A short summary of these results is presented below.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Investigation of encapsulin nanocompartment systems as ascaffold for biomaterials synthesis in Rhodococcus species (DOE ECRP Annual Report 2023)

Engineered protein compartmentalization systems hold significant promise to enhance reaction efficiencies through co-localization, concentration, and sequestration of biosynthetic pathways. As such, they have the potential to enable the bioproduction of next generation bioproducts and biomaterials in genetically engineered microbes in support of DOE’s mission to build a strong bioeconomy. Among systems of particular interest are protein nanocompartment systems called encapsulins that are natively produced by a variety of bacteria including those with a high potential for bioproduction. This ECRP project is focused on understanding how encapsulins can be used to enhance the biosynthesis of next-generation biomaterials in Rhodococcus species. Specifically, we seek: (1) to probe the mechanistic basis for how these compartments are regulated, biosynthesized, and maintained, and (2) to engineer these systems to achieve new biosynthetic functions (e.g., CdS nanoparticle biosynthesis). We anticipate that this work will establish encapsulin compartmentalization systems as a means of improving yields and enabling biosynthetic routes toward new biomaterials, thus advancing the U.S. bioeconomy.

59 BASIC BIOLOGICAL SCIENCES↗

Investigating carbon stabilization in soils via mineral adsorption: What are we missing when we define mineral associated organic matter

Understanding carbon (C) fluxes released from soil to atmosphere is critical to regulating global climate change. Soil minerals play a crucial role in stabilizing C, based on recent studies which have found that mineral associated C can be stored in soils for decades to centuries longer than non-mineral associated C. We aim to maximize C sequestration via mineral adsorption in soils. To achieve this objective, it is important to understand the potential impacts of C stabilization via adsorption to mineral surfaces. Particularly, investigating the quantitative impacts of C sorption to minerals is novel to understanding and implementing multi-scale biogeochemical processes of C stabilization in soils. We will conduct a literature review on potential impacts of C sorption to minerals, thereby contributing to the net C storage in soils. Our findings will allow us to quantitatively understand soil C changes and durability at molecular and ecosystem scales, fulfilling existing scientific gaps in the community as well as interests of sponsors, such as DOE-BER.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗