Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Lignite”

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 505 records · Page 28
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens

This is the Final Progress Report for DOE-funded research project DE-PS02-08ER08-01 titled “Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens”. The project focuses on the effects of low-linear energy transfer (LET) radiation on the ocular lens. The lens is an exquisitely radiosensitive tissue with a highly-ordered molecular structure that is amenable to non-invasive optical study from the periphery. These merits point to the lens as an ideal target for laser-based molecular biodosimetry (MBD). Following exposure to different types of ionizing radiations, the lens demonstrates molecular changes (e.g., oxidation, racemization, crosslinkage, truncation, aggregation, etc.) that impact the structure and function of the long-lived proteins in the cytosol of lens fiber cells. The vast majority of proteins in the lens comprise the highly-ordered crystallins. These highly conserved lens proteins are amongst the most concentrated and stable in the body. Once synthesized, the crystallins are retained in the fiber cell cytoplasm for life. Taken together, these properties point to the lens as an ideal system for quantitative in vivo MBD assessment using quasi-elastic light scattering (QLS) analysis. In this project, we deploy a purpose-designed non-invasive infrared laser QLS instrument as a quantitative tool for longitudinal assessment of pre-cataractous molecular changes in the lenses of living mice exposed to low-dose low-LET radiation compared to non-irradiated sham controls. We hypothesize that radiation exposure will induce dose-dependent changes in the molecular structure of matrix proteins in the lens. Mechanistic assays to ascertain radiation-induced molecular changes in the lens focus on protein aggregation and gene/protein expression patterns. We anticipate that this study will contribute to our understanding of early molecular changes associated with radiation-induced tissue pathology. This study also affords potential for translational development of molecular biodosimetry instrumentation to assess human exposure to mixed radiation fields.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Improved Mobility Control for Carbon Dioxide (CO{sub 2}) Enhanced Oil Recovery Using Silica-Polymer-Initiator (SPI) Gels

SPI gels are multi-component silicate based gels for improving (areal and vertical) conformance in oilfield enhanced recovery operations, including water-floods and carbon dioxide (CO{sub 2}) floods, as well as other applications. SPI mixtures are like-water when pumped, but form light up to very thick, paste-like gels in contact with CO{sub 2}. When formed they are 3 to 10 times stronger than any gelled polyacrylamide gel now available, however, they are not as strong as cement or epoxy, allowing them to be washed / jetted out of the wellbore without drilling. This DOE funded project allowed 8 SPI field treatments to be performed in 6 wells (5 injection wells and 1 production well) in 2 different fields with different operators, in 2 different basins (Gulf Coast and Permian) and in 2 different rock types (sandstone and dolomite). Field A was in a central Mississippi sandstone that injected CO{sub 2} as an immiscible process. Field B was in the west Texas San Andres dolomite formation with a mature water-alternating-gas miscible CO{sub 2} flood. Field A treatments are now over 1 year old while Field B treatments have only 4 months data available under variable WAG conditions. Both fields had other operational events and well work occurring before/ during / after the treatments making definitive evaluation difficult. Laboratory static beaker and dynamic sand pack tests were performed with Ottawa sand and both fields’ core material, brines and crude oils to improve SPI chemistry, optimize SPI formulations, ensure SPI mix compatibility with field rocks and fluids, optimize SPI treatment field treatment volumes and methods, and ensure that strong gels set in the reservoir. Field quality control procedures were designed and utilized. Pre-treatment well (surface) injectivities ranged from 0.39 to 7.9 MMCF/psi. The SPI treatment volumes ranged from 20.7 cubic meters (m{sup 3}, 5460 gallons/ 130 bbls) to 691 m{sup 3} (182,658 gallons/ 4349 bbls). Various size and types of chemical/ water buffers before and after the SPI mix ensured that pre-gelled SPI mix got out into the formation before setting into a gel. SPI gels were found to be 3 to 10 times stronger than any commercially available cross-linked polyacrylamide gels based on Penetrometer and Bulk Gel Shear Testing. Because of SPI’s unique chemistry with CO{sub 2}, both laboratory and later field tests demonstrated that multiple, smaller volume SPI treatments maybe more effective than one single large SPI treatment. CO{sub 2} injectivities in injection well in both fields were reduced by 33 to 70% indicating that injected CO{sub 2} is now going into new zones. This reduction has lasted 1+ year in Field A. Oil production increased and CO{sub 2} production decreased in 5 Field A production wells, offsets to Well #1 injector, for a total of about 2,250 m{sup 3} (600,000 gallons/ 14,250 bbls) of incremental oil production- a $140 / SPI bbl return. Treated marginal production well, Field A Well #2, immediately began showing increased oil production totaling 238 m{sup 3} (63,000 gallons/ 1500 BBLs) over 1 year and an immediate 81% reduced gas-oil ratio.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Pre-feasibility Study to Identify Opportunities for Increasing CO 2 Storage in Deep, Saline Aquifers by Active Aquifer Management and Treatment of Produced Water

In this report, we present initial estimates of CO 2 injectivity and plume radius for injection of 0.1 MT/yr and 1 MT/yr. Results for 1 and 10 years of injection are used to show how the plume from a single injector well could grow through time for a simplified, idealized system. Most results are for a 2 km deep injection well, while several results from a deeper plume are also presented to demonstrate the impact of changing depth and temperature.

Coal, Lignite, & Peat(01)↗
DOE OSTI2014

Recovery Act: Oxy-Combustion Technology Development for Industrial-Scale Boiler Applications. Task 4 - Testing in Alstom's 15 MW th Boiler Simulation Facility

Alstom Power Inc. (Alstom), under U.S. DOE/NETL Cooperative Agreement No. DE-NT0005290, is conducting a development program to generate detailed technical information needed for application of oxy-combustion technology. The program is designed to provide the necessary information and understanding for the next step of large-scale commercial demonstration of oxy combustion in tangentially fired boilers and to accelerate the commercialization of this technology. The main project objectives include: Design and develop an innovative oxyfuel system for existing tangentially-fired boiler units that minimizes overall capital investment and operating costs; Evaluate performance of oxyfuel tangentially fired boiler systems in pilot scale tests at Alstom’s 15 MWth tangentially fired Boiler Simulation Facility (BSF); Address technical gaps for the design of oxyfuel commercial utility boilers by focused testing and improvement of engineering and simulation tools; Develop the design, performance and costs for a demonstration scale oxyfuel boiler and auxiliary systems; Develop the design and costs for both industrial and utility commercial scale reference oxyfuel boilers and auxiliary systems that are optimized for overall plant performance and cost; and, Define key design considerations and develop general guidelines for application of results to utility and different industrial applications. The project was initiated in October 2008 and the scope extended in 2010 under an ARRA award. The project is scheduled for completion by April 30, 2014. Central to the project is 15 MWth testing in the BSF, which provided in-depth understanding of oxy-combustion under boiler conditions, detailed data for improvement of design tools, and key information for application to commercial scale oxy-fired boiler design. Eight comprehensive 15 MWth oxy-fired test campaigns were performed with different coals, providing detailed data on combustion, emissions, and thermal behavior over a matrix of fuels, oxy-process variables and boiler design parameters. Significant improvement of CFD modeling tools and validation against 15 MWth experimental data has been completed. Oxy-boiler demonstration and large reference designs have been developed, supported with the information and knowledge gained from the 15 MWth testing. This report addresses the results from the 15 MWth testing in the BSF.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Novel Non-Aqueous CO 2 Solvents and Capture Process with Substantially Reduced Energy Penalties (Final Scientific/Technical Report)

The overall objective of this 3 year project was to rapidly advance the development a family of promising NAS formulations from proof-of-concept testing through to testing in a representative process arrangement to determine the potential for this novel solvent-based process to substantially reduce (i.e., >40%) the energy demand and cost of CO 2 capture from fossil fuel-fired electricity generating units. The goal of this project was to thoroughly characterize the NASs and evaluate their performance in a small process unit to understand their potential to lower the energy demand of a CO 2 capture process and demonstrate feasibility. Detailed characterization of the thermodynamic properties of the NASs revealed large working capacities under low regeneration temperatures (i.e., <100°C) and lower heats of absorption than conventional aqueous amine solvents. The thermal energy demand for these promising NAS formulations was estimated to be approximately 40% less than conventional aqueous-amine solvents (2.06-2.15 GJt / tonne CO 2 vs 3.6 GJt / tonne CO 2 ).

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Direct Utilization of Coal Syngas in High Temperature Fuel Cells

This EPSCoR project had two primary goals: (i) to build infrastructure and work force at WVU to support long-term research in the area of fuel cells and related sciences; (ii) study effects of various impurities found in coal-syngas on performance of Solid Oxide Fuel Cells (SOFC). As detailed in this report the WVU research team has made significant accomplishments in both of these areas. What follows is a brief summary of these accomplishments: State-of-the-art test facilities and diagnostic tools have been built and put into use. These include cell manufacturing, half-cell and full-cell test benches, XPS, XRD, TEM, Raman, EDAX, SEM, EIS, and ESEM equipment, unique in-situ measurement techniques and test benches (Environmental EM, Transient Mass-Spectrometer-MS, and IR Optical Temperature measurements). In addition, computational capabilities have been developed culminating in a multi-scale multi-physics fuel cell simulation code, DREAM-SOFC, as well as a Beowulf cluster with 64 CPU units. We have trained 16 graduate students, 10 postdoctoral fellows, and recruited 4 new young faculty members who have actively participated in the EPSCoR project. All four of these faculty members have already been promoted to the tenured associate professor level. With the help of these faculty and students, we were able to secure 14 research awards/contracts amounting to a total of circa $5.0 Million external funding in closely related areas of research. Using the facilities mentioned above, the effects of PH3, HCl, Cl2, and H2S on cell performance have been studied in detail, mechanisms have been identified, and also remedies have been proposed and demonstrated in the laboratory. For example, it has been determined that PH3 reacts rapidly with Ni to from secondary compounds which may become softer or even melt at high temperature and then induce Ni migration to the surface of the cell changing the material and micro-structural properties of the cell drastically. It is found that the extent of steam and current load accelerate the degradation caused by PH3. A unique filtering technique has been proposed to reduce the effect of PH3. In addition, various cell materials have been proposed to reduce the rate of degradation caused by H2S. Furthermore, a three-dimensional, transient multi-physics model has been formulated to describe primary transport processes and electro-chemical reactions occurring within the cell. This model has been validated using data gathered from accelerated tests. The validated model then has been used to study the degradation rates under a range of operating conditions and impurity levels. This has resulted in a procedure that uses both experiments and simulations to predict the life-time of a cell operating with syngas with known concentration of trace impurities. Finally all the experience and knowledge gained has been disseminated via 39 journal papers and 43 presentations/posters/conference papers.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Advanced Systems for Preprocessing and Characterizing Coal-Biomass Mixtures as Next-Generation Fuels and Feedstocks

The research activities presented in this report are intended to address the most critical technical challenges pertaining to coal-biomass briquette feedstocks. Several detailed investigations were conducted using a variety of coal and biomass feedstocks on the topics of (1) coal-biomass briquette production and characterization, (2) gasification of coal-biomass mixtures and briquettes, (3) combustion of coal-biomass mixtures and briquettes, and (4) conceptual engineering design and economic feasibility of briquette production. The briquette production studies indicate that strong and durable co-firing feedstocks can be produced by co-briquetting coal and biomass resources commonly available in the United States. It is demonstrated that binderless coal-biomass briquettes produced at optimized conditions exhibit very high strength and durability, which indicates that such briquettes would remain competent in the presence of forces encountered in handling, storage and transportation. The gasification studies conducted demonstrate that coal-biomass mixtures and briquettes are exceptional gasification feedstocks, particularly with regard to the synergistic effects realized during devolatilization of the blended materials. The mixture combustion studies indicate that coal-biomass mixtures are exceptional combustion feedstocks, while the briquette combustion study indicates that the use of blended briquettes reduces NO x , CO 2 , and CO emissions, and requires the least amount of changes in the operating conditions of an existing coal-fired power plant. Similar results were obtained for the physical durability of the pilot-scale briquettes compared to the bench-scale tests. Finally, the conceptual engineering and feasibility analysis study for a commercial-scale briquetting production facility provides preliminary flowsheet and cost simulations to evaluate the various feedstocks, equipment selection and operating parameters.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

SECA Coal-Based Systems - FuelCell Energy, Inc.

The overall goal of this U.S. Department of Energy (DOE) sponsored project is the development of solid oxide fuel cell (SOFC) cell and stack technology suitable for use in highly-efficient, economically-competitive central generation power plant facilities fueled by coal synthesis gas (syngas). This program incorporates the following supporting objectives: • Reduce SOFC-based electrical power generation system cost to $700 or less (2007 dollars) for a greater than 100 MW Integrated Gasification Fuel Cell (IGFC) power plant, exclusive of coal gasification and CO 2 separation subsystem costs. • Achieve an overall IGFC power plant efficiency of at least 50%, from coal (higher heating value or HHV) to AC power (exclusive of CO 2 compression power requirement). • Reduce the release of CO2 to the environment in an IGFC power plant to no more than 10% of the carbon in the syngas. • Increase SOFC stack reliability to achieve a design life of greater than 40,000 hours. At the inception of the project, the efforts were focused on research, design and testing of prototype planar SOFC power generators for stationary applications. FuelCell Energy, Inc. successfully completed the initial stage of the project by meeting the program metrics, culminating in delivery and testing of a 3 kW system at National Energy Technology Laboratory (NETL). Subsequently, the project was re-aligned into a three phase effort with the main goal to develop SOFC technology for application in coal-fueled power plants with >90% carbon capture. Phase I of the Coal-based efforts focused on cell and stack size scale-up with concurrent enhancement of performance, life, cost, and manufacturing characteristics. Also in Phase I, design and analysis of the baseline (greater than 100 MW) power plant system—including concept identification, system definition, and cost analysis—was conducted. Phase II efforts focused on development of a ≥25 kW SOFC stack tower incorporating multiple stack building blocks of scaled-up cells, suitable for integration into a large-scale fuel cell power module. Activities in Phase II also included the development of the baseline system, factory cost estimate for the baseline plant’s power block, and conceptual design of a natural gas fueled sub-MW system to be used for testing and verification of the fuel cell stacks in a system environment. The specific objective for Phase III was the validation of the performance and robustness of stacks and scaled stack arrays suitable for use in large-scale power generation systems such as an IGFC with reliable, fail-safe operation being of paramount importance. The work culminated in the verification tests of a 60 kW SOFC stack module in a power plant facility. This final technical report summarizes the progress made during the project period. Significant progress was made in the areas of cell and stack technology development, stack module design, sub-scale module tests, Baseline Power Plant system development and Proof-of- Concept Module unit design. The development of this technology will significantly advance the nation’s energy security and independence interests while simultaneously addressing environmental concerns, including greenhouse gas emissions and water usage.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Gasification Characteristics of Coal/Biomass Mixed Fuels

A research project was undertaken that had the overall objective of developing the models needed to accurately predict conversion rates of coal/biomass mixtures to synthesis gas under conditions relevant to a commercially-available coal gasification system configured to co-produce electric power as well as chemicals and liquid fuels. In our efforts to accomplish this goal, experiments were performed in an entrained flow reactor in order to produce coal and biomass chars at high heating rates and temperatures, typical of the heating rates and temperatures fuel particles experience in real systems. Mixed chars derived from coal/biomass mixtures containing up to 50% biomass and the chars of the pure coal and biomass components were subjected to a matrix of reactivity tests in a pressurized thermogravimetric analyzer (TGA) in order to obtain data on mass loss rates as functions of gas temperature, pressure and composition as well as to obtain information on the variations in mass specific surface area during char conversion under kinetically-limited conditions. The experimental data were used as targets when determining the unknown parameters in the chemical reactivity and specific surface area models developed. These parameters included rate coefficients for the reactions in the reaction mechanism, enthalpies of formation and absolute entropies of adsorbed species formed on the carbonaceous surfaces, and pore structure coefficients in the model used to describe how the mass specific surface area of the char varies with conversion. So that the reactivity models can be used at high temperatures when mass transport processes impact char conversion rates, Thiele modulus – effectiveness factor relations were also derived for the reaction mechanisms developed. In addition, the reactivity model and a mode of conversion model were combined in a char-particle gasification model that includes the effects of chemical reaction and diffusion of reactive gases through particle pores and energy exchange between the particle and its environment. This char-particle gasification model is capable of predicting the average mass loss rates, sizes, apparent densities, specific surface areas, and temperatures of the char particles produced when co-firing coal and biomass to the type environments established in entrained flow gasifiers operating at high temperatures and elevated pressures.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Computational Capabilities for Predictions of Interactions at the Grain Boundary of Refractory Alloys

New high performance refractory alloys are critically required for improving efficiency and decreasing CO 2 emissions of fossil energy systems. The development of these materials remains slow because it is driven by a trial-and-error experimental approach and lacks a rational design approach. Atomistic Molecular Dynamic (MD) design has the potential to accelerate this development through the prediction of mechanical properties and corrosion resistance of new materials. The success of MD simulations depends critically on the fidelity of interatomic potentials. This project, in collaboration with Penn State, has focused on developing and validating high quality quantum mechanics based reactive potentials, ReaxFF, for Ni-Fe-Al-Cr-O-S system. A larger number of accurate density functional theory (DFT) calculations were performed to generate data for parameterizing the ReaxFF potentials. These potentials were then used in molecular dynamics (MD) and molecular dynamics-Monte Carlo (MD-MC) for much larger system to study for which DFT calculation would be prohibitively expensive, and to understand a number of chemical phenomena Ni-Fe-Al-Cr-O-S based alloy systems . These include catalytic oxidation of butane on clean Cr 2 O 3 and pyrite/Cr 2 O 3 , interfacial reaction between Cr 2 O 3 (refractory material) and Al 2 O 3 (slag), cohesive strength of at the grain boundary of S-enriched Cr compared to bulk Cr and Ssegregation study in Al, Al 2 O 3 , Cr and Cr 2 O 3 with a grain structure. The developed quantum based ReaxFF potential are available from the authors upon request. During this project, a number of papers were published in peer-reviewed journals. In addition, several conference presentations were made.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Gulf of Mexico miocene CO₂ site characterization mega transect

This project characterized the Miocene-age sub-seafloor stratigraphy in the near-offshore portion of the Gulf of Mexico adjacent to the Texas coast. The large number of industrial sources of carbon dioxide (CO₂) in coastal counties and the high density of onshore urbanization and environmentally sensitive areas make this offshore region extremely attractive for long-term storage of carbon dioxide emissions from industrial sources (CCS). The study leverages dense existing geologic data from decades of hydrocarbon exploration in and around the study area to characterize the regional geology for suitability and storage capacity. Primary products of the study include: regional static storage capacity estimates, sequestration “leads” and prospects with associated dynamic capacity estimates, experimental studies of CO₂-brine-rock interaction, best practices for site characterization, a large-format ‘Atlas’ of sequestration for the study area, and characterization of potential fluid migration pathways for reducing storage risks utilizing novel high-resolution 3D (HR3D) seismic surveys. In addition, three subcontracted studies address source-to-sink matching optimization, offshore well bore management and environmental aspects. The various geologic data and interpretations are integrated and summarized in a series of cross-sections and maps, which represent a primary resource for any near-term commercial deployment of CCS in the area. The regional study characterized and mapped important geologic features (e.g., Clemente-Tomas fault zone, the regionally extensive Marginulina A and Amphistegina B confining systems, etc.) that provided an important context for regional static capacity estimates and specific sequestration prospects of the study. A static capacity estimate of the majority of the Study area (14,467 mi 2 ) was estimated at 86 metric Gigatonnes. While local capacity estimates are likely to be lower due to reservoir-scale characteristics, the offshore Miocene interval is a storage resource of National interest for providing CO₂ storage as an atmospheric emissions abatement strategy. The natural petroleum system was used as an analog to infer seal quality and predict possible migration pathways of fluids in an engineered system of anthropogenic CO₂ injection and storage. The regional structural features (e.g., Clemente-Tomas fault zone) that exert primary control on the trapping and distribution of Miocene hydrocarbons are expected to perform similarly for CCS. Industrial-scale CCS will require storage capacity utilizing well-documented Miocene hydrocarbon (dominantly depleted gas) fields and their larger structural closures, as well as barren (unproductive, brine-filled) closures. No assessment was made of potential for CO₂ utilization for enhanced oil and gas recovery. The use of 3D numerical fluid flow simulations have been used in the study to greatly assist in characterizing the potential storage capacity of a specific reservoir. Due to the complexity of geologic systems (stratigraphic heterogeneity) and inherent limitations on producing a 3D geologic model, these simulations are typically simplified scenarios that explore the influence of model property variability (sensitivity study). A specific site offshore San Luis Pass (southern Galveston Island) was undertaken successfully, indicating stacked storage potential. Downscaling regional capacity estimates to the local scale (and the inverse) has proven challenging, and remains an outstanding gap in capacity assessments. In order to characterize regional seal performance and identify potential brine and CO₂ leakage pathways, results from three high-resolution 3D (HR3D) seismic datasets acquired by the study using novel HR3D (P-Cable) acquisition system showed steady and significant improvements in data quality because of improved acquisition and processing technique. Finely detailed faults and stratigraphy in the shallowest 1000 milliseconds (~800 m) of data allowed for the identification and mapping of unconformable surfaces including what is probably a surface associated with the last Pleistocene glacial lowstand. The identification of a previously unrecognized (in commercial seismic data) gas chimney that was clearly defined in the 2013 HR3D survey, indicates that HR3D surveys may be useful as both a characterization tool for the overburden of a potential carbon sequestration site and as an additional monitoring tool for future engineered injection sites. Geochemical modeling indicated that injection of CO₂ would result in minor dissolution of calcite, K-feldspar and albite. In addition, modeling of typical brines in Miocene age rocks indicate that approximately 5% of injection capacity would result from CO₂ dissolution into the brine. After extensive searches, no rock samples of the Marginulina A and Amphistegina B seals (“caprocks”) were obtained, but analyses of available core samples of other Miocene age mudrocks (seals or caprocks) indicate that they have sealing ability sufficient for potential CO 2 storage in underlying sandstone units.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High-T and Dynamic Gas Pressure in Harsh Environments

This is the final report for the program “Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High Temperature and Dynamic Gas Pressure in Harsh Environments”, funded by NETL, and performed by Missouri University of Science and Technology, Clemson University and University of Cincinnati from October 1, 2009 to September 30, 2014. Securing a sustainable energy economy by developing affordable and clean energy from coal and other fossil fuels is a central element to the mission of The U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL). To further this mission, NETL funds research and development of novel sensor technologies that can function under the extreme operating conditions often found in advanced power systems. The main objective of this research program is to conduct fundamental and applied research that will lead to successful development and demonstration of robust, multiplexed, microstructured silica and single-crystal sapphire fiber sensors to be deployed into the hot zones of advanced power and fuel systems for simultaneous measurements of high temperature and gas pressure. The specific objectives of this research program include: 1) Design, fabrication and demonstration of multiplexed, robust silica and sapphire fiber temperature and dynamic gas pressure sensors that can survive and maintain fully operational in high-temperature harsh environments. 2) Development and demonstration of a novel method to demodulate the multiplexed interferograms for simultaneous measurements of temperature and gas pressure in harsh environments. 3) Development and demonstration of novel sapphire fiber cladding and low numerical aperture (NA) excitation techniques to assure high signal integrity and sensor robustness.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Temperature Trends in Coal Char Combustion under Oxy-fuel Conditions for the Determination of Kinetics

Oxy-fuel combustion technology with carbon capture and storage could significantly reduce global CO 2 emissions, a greenhouse gas. Implementation can be aided by computational fluid dynamics (CFD) simulations, which require an accurate understanding of coal particle kinetics as they go through combustion in a range of environments. To understand the kinetics of pulverized coal char combustion, a heated flow reactor was operated under a wide range of experimental conditions. We varied the environment for combustion by modifying the diluent gas, oxygen concentration, gas flow rate, and temperature of the reactor/reacting gases. Measurements of reacting particle temperatures were made for a sub-bituminous and bituminous coal char, in environments with CO 2 or N 2 as the diluent gas, with 12, 24, and 36 vol-% oxygen concentration, at 50, 80, 100, and 200 standard liters per minute flowing through the reactor, reactor temperatures of 1200, 1400 K, at pressures slightly above atmospheric. The data shows consistent increasing particle temperature with increased oxygen concentration, reactor temperature and higher particle temperatures for N 2 diluent than CO 2 . We also see the effects of CO 2 gasification when different ranks of coal are used, and how the reduction in the temperature due to the CO 2 diluent is greater for the coal char that has higher reactivity. Quantitative measurements for temperature are not yet complete due to ongoing calibration of detection systems.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2015

Dedicated Beamline Facilities for Catalytic Research. Synchrotron Catalysis Consortium (SCC)

Synchrotron spectroscopies offer unique advantages over conventional techniques, including higher detection sensitivity and molecular specificity, faster detection rate, and more in-depth information regarding the structural, electronic and catalytic properties under in-situ reaction conditions. Despite these advantages, synchrotron techniques are often underutilized or unexplored by the catalysis community due to various perceived and real barriers, which will be addressed in the current proposal. Since its establishment in 2005, the Synchrotron Catalysis Consortium (SCC) has coordinated significant efforts to promote the utilization of cutting-edge catalytic research under in-situ conditions. The purpose of the current renewal proposal is aimed to provide assistance, and to develop new sciences/techniques, for the catalysis community through the following concerted efforts: Coordinating the implementation of a suite of beamlines for catalysis studies at the new NSLS-II synchrotron source; Providing assistance and coordination for catalysis users at an SSRL catalysis beamline during the initial period of NSLS to NSLS II transition; Designing in-situ reactors for a variety of catalytic and electrocatalytic studies; Assisting experimental set-up and data analysis by a dedicated research scientist; Offering training courses and help sessions by the PIs and co-PIs.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Cooling Strategies for Vane Leading Edges in a Syngas Environment Including Effects of Deposition and Turbulence

The Department of Energy has goals to move land based gas turbine systems to alternate fuels including coal derived synthetic gas and hydrogen. Coal is the most abundant energy resource in the US and in the world and it is economically advantageous to develop power systems which can use coal. Integrated gasification combined cycles are (IGCC) expected to allow the clean use of coal derived fuels while improving the ability to capture and sequester carbon dioxide. These cycles will need to maintain or increase turbine entry temperatures to develop competitive efficiencies. The use of coal derived syngas introduces a range of potential contaminants into the hot section of the gas turbine including sulfur, iron, calcium, and various alkali metals. Depending on the effectiveness of the gas clean up processes, there exists significant likelihood that the remaining materials will become molten in the combustion process and potentially deposit on downstream turbine surfaces. Past evidence suggests that deposition will be a strong function of increasing temperature. Currently, even with the best gas cleanup processes a small level of particulate matter in the syngas is expected. Consequently, particulate deposition is expected to be an important consideration in the design of turbine components. The leading edge region of first stage vanes most often have higher deposition rates than other areas due to strong fluid acceleration and streamline curvature in the vicinity of the surface. This region remains one of the most difficult areas in a turbine nozzle to cool due to high inlet temperatures and only a small pressure ratio for cooling. The leading edge of a vane often has relatively high heat transfer coefficients and is often cooled using showerhead film cooling arrays. The throat of the first stage nozzle is another area where deposition potentially has a strongly adverse effect on turbine performance as this region meters the turbine inlet flow. Based on roughness levels found on in service vanes (Bons, et al., 2001, up to 300 microns) flow blockage in first stage turbine nozzles can easily reach 1 to 2 percent in conventional turbines. Deposition levels in syngas fueled gas turbines are expected to be even more problematic. The likelihood of significant deposition to the leading edge of vanes in a syngas environment indicates the need to examine this effect on the leading edge cooling problem. It is critical to understand the influence of leading edge geometry and turbulence on deposition rates for both internally and showerhead cooled leading edge regions. The expected level of deposition in a vane stagnation region not only significantly changes the heat transfer problem but also suggests that cooling arrays may clog. Addressing the cooling issue suggests a need to better understand stagnation region heat transfer with realistic roughness as well as the other variables affecting transport near the leading edge. Also, the question of whether leading edge regions can be cooled internally with modern cooling approaches should also be raised, thus avoiding the clogging issue. Addressing deposition in the pressure side throat region of the nozzle is another critical issue for this environment. Issues such as examining the protective effect of slot and full coverage discrete-hole film cooling on limiting deposition as well as the influence of roughness and turbulence on effectiveness should be raised. The objective of this present study is to address these technical challenges to help enable the development of high efficiency syngas tolerant gas turbine engines.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Research and development to prepare and characterize robust coal/biomass mixtures for direct co-feeding into gasification systems

This project was initiated on October 1, 2010 and utilizes equipment and research supported by the Department of Energy, National Energy Technology Laboratory, under Award Number DE- FE0005349. It is also based upon previous work supported by the Department of Energy, National Energy Technology Laboratory, under Award Numbers DOE-DE-FG36-01GOl1082, DE-FG36-02G012011 or DE-EE0000272. The overall goal of the work performed was to demonstrate and assess the economic viability of fast hydrothermal carbonization (HTC) for transforming lignocellulosic biomass into a densified, friable fuel to gasify like coal that can be easily blended with ground coal and coal fines and then be formed into robust, weather-resistant pellets and briquettes.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Assessing Reservoir Depositional Environments to Develop and Quantify Improvements in CO 2 Storage Efficiency. A Reservoir Simulation Approach

The storage potential and fluid movement within formations are dependent on the unique hydraulic characteristics of their respective depositional environments. Storage efficiency (E) quantifies the potential for storage in a geologic depositional environment and is used to assess basinal or regional CO 2 storage resources. Current estimates of storage resources are calculated using common E ranges by lithology and not by depositional environment. The objectives of this project are to quantify E ranges and identify E enhancement strategies for different depositional environments via reservoir simulation studies. The depositional environments considered include deltaic, shelf clastic, shelf carbonate, fluvial deltaic, strandplain, reef, fluvial and alluvial, and turbidite. Strategies considered for enhancing E include CO 2 injection via vertical, horizontal, and deviated wells, selective completions, water production, and multi-well injection. Conceptual geologic and geocellular models of the depositional environments were developed based on data from Illinois Basin oil fields and gas storage sites. The geologic and geocellular models were generalized for use in other US sedimentary basins. An important aspect of this work is the development of conceptual geologic and geocellular models that reflect the uniqueness of each depositional environment. Different injection well completions methods were simulated to investigate methods of enhancing E in the presence of geologic heterogeneity specific to a depositional environment. Modeling scenarios included horizontal wells (length, orientation, and inclination), selective and dynamic completions, water production, and multiwell injection. A Geologic Storage Efficiency Calculator (GSECalc) was developed to calculate E from reservoir simulation output. Estimated E values were normalized to diminish their dependency on fluid relative permeability. Classifying depositional environments according to normalized baseline E ranges ranks fluvial deltaic and turbidite highest and shelf carbonate lowest. The estimated average normalized baseline E of turbidite, and shelf carbonate depositional environments are 42.5% and 13.1%, with corresponding standard deviations of 11.3%, and 3.10%, respectively. Simulations of different plume management techniques suggest that the horizontal well, multi-well injection with brine production from blanket vertical producers are the most efficient E enhancement strategies in seven of eight depositional environments; for the fluvial deltaic depositional environment, vertical well with blanket completions is the most efficient. This study estimates normalized baseline E ranges for eight depositional environments, which can be used to assess the CO 2 storage resource of candidate formations. This study also improves the general understanding of depositional environment’s influence on E. The lessons learned and results obtained from this study can be extrapolated to formations in other US basins with formations of similar depositional environments, which should be used to further refine regional and national storage resource estimates in future editions of the Carbon Utilization and Storage Atlas of the United States. Further study could consider the economic feasibility of the E enhancement strategies identified here.

01 COAL, LIGNITE, AND PEAT↗