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50550: Waste Stream Profile, TA-55 TRP-III Fire System Replacement System-Concrete for Recycle
Abstract not provided.
50608: Waste Stream Profile, TA-55 TRP-III Fire System Replacement System-Asphalt for Recycle
Abstract not provided.
Characterizing Impacts of Dry Coal Feeding in High Pressure Oxy-Coal Combustion Systems
Reaction Engineering International (REI) has managed a team of experts from the University of Utah, Southeast University (SEU) in Nanjing, China, Electric Power Research Institute (EPRI), Corrosion Management Ltd. (C-M), Praxair, and Brigham Young University (BYU) to investigate dry pulverized coal feeding for pressurized oxy-coal combustion. Dry feed firing systems for entrained flow, pressurized, oxy-coal combustors have not been well developed, although related technologies have been used in the Shell Gasification Process and for pressurized fluid bed combustion. DOE-funded research recently completed at REI and the University of Utah focused on characterizing impacts of high temperatures and pressures in oxy-coal combustion systems. For high pressure combustion, that research used a coal slurry feed into a 17 bar pressurized combustor. As a consequence of that research, it was identified that fuel feeding and firing system flexibility are challenges that require attention. Based on that experience, the approach of using a coal slurry feed system leads to challenges in producing consistent atomization of the slurry, which causes burnout problems, especially at high pressures. In addition, slurry atomization processes may be difficult to scale to sizes appropriate for practical commercial use. Dry pressurized coal burner systems, on the other hand, have the potential to yield efficiency gains, improve flexibility and facilitate applications at larger scales. Experimental work was conducted at the University of Utah Industrial Combustion and Gasification Research Facility as well as the 100 kW pressurized oxy-coal combustor (POC) facility at Brigham Young University. Mechanism development and CFD-based combustion and dense-phase flow modeling were performed at REI. Successful completion of the project objectives has resulted in the following key deliverables: 1) Design and prototype of a pressurized pulverized coal feeding and oxy-firing system 2) Data from a 100kW, pressurized (15 bar) entrained flow reactor with a dry feeding delivery and burner system that describes flame characteristics, radiative heat flux profiles, carbon burnout, along with characteristics of ash aerosols, fouling, and slagging. 3) Validated and transportable models that describe the relevant conditions in pressurized oxy-combustion systems and that can be used for scale-up and optimization. 4) Principles to guide design of high pressure, pilot-scale and full-scale coal oxy-firing systems. 5) Assessment of pressurized oxy-combustion impacts on key parameters relevant to oxy-coal fired utility boilers such as coal devolatilization, char oxidation, mineral matter transformation, deposition, and corrosion. The experimental data, pressurized oxy-firing system principles, and process mechanisms provided by this work can be used by electric utilities, boiler OEMs, equipment suppliers, design firms, software vendors, consultants and government agencies to assess the use of high temperature and high pressure oxy-combustion in current research and to guide development of new oxy-coal boiler designs.
Pilot Testing of Amine-Based Solvent at Low-Rank Coal Fired Power System
Conference presentation for the 2023 International Freiberg Conference on Circular Carbon Technologies, Rotterdam, Netherlands, September 24–29, 2023. This presentation describes pilot testing of an amine-based CO₂ capture system at Coal Creek Station, examining solvent performance, system design, and operating conditions for a low-rank coal-fired power plant. The Mitsubishi Heavy Industries KM CDR (KS-1) process is assessed using pilot-scale data to inform capture efficiency, solvent condition, and integration considerations.
Characterizing the Capacity of Cast Iron Fittings in Fire Suppression Systems that Support Seismic Forces
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Evaluation of Global Fire Simulations in CMIP6 Earth System Models
Fire is the primary form of terrestrial ecosystem disturbance on a global scale and an important Earth system process. Most Earth system models (ESMs) have incorporated fire modeling, with 19 of them submitting model outputs of fire-related variables to the Coupled Model Intercomparison Project Phase 6 (CMIP6). This study provides the first comprehensive evaluation of CMIP6 historical fire simulations by comparing them with multiple satellite-based products and charcoal-based historical reconstructions. Our results show that most CMIP6 models simulate the present-day global burned area and fire carbon emissions within the range of satellite-based products. They also capture the major features of observed spatial patterns and seasonal cycles, the relationship of fires with precipitation and population density, and the influence of the El Niño–Southern Oscillation (ENSO) on the interannual variability of tropical fires. Regional fire carbon emissions simulated by the CMIP6 models from 1850 to 2010 generally align with the charcoal-based reconstructions, although there are regional mismatches, such as in southern South America and eastern temperate North America prior to the 1910s and in temperate North America, eastern boreal North America, Europe, and boreal Asia since the 1980s. The CMIP6 simulations have addressed three critical issues identified in CMIP5: (1) the simulated global burned area being less than half of that of the observations, (2) the failure to reproduce the high burned area fraction observed in Africa, and (3) the weak fire seasonal variability. Furthermore, the CMIP6 models exhibit improved accuracy in capturing the observed relationship between fires and both climatic and socioeconomic drivers and better align with the historical long-term trends indicated by charcoal-based reconstructions in most regions worldwide. However, the CMIP6 models still fail to reproduce the decline in global burned area and fire carbon emissions observed over the past 2 decades, mainly attributed to an underestimation of anthropogenic fire suppression, and the spring peak in fires in the Northern Hemisphere midlatitudes, mainly due to an underestimation of crop fires. In addition, the model underestimates the fire sensitivity to wet–dry conditions, indicating the need to improve fuel wet-ness estimation. Based on these findings, we present specific guidance for fire scheme development and suggest a postprocessing methodology for using CMIP6 multi-model outputs to generate reliable fire projection products.
Plasma Ignition and Combustion Stabilization Technology to Improve Flexible Operation, Reliability and Economics of an Existing Coal-Fired Boiler
GE Steam Power, Inc. (GE) proposed to improve reliability, flexibility, and economics of an existing coal-fired power plant by applying a new advanced technology developed by GE, a plasma-assisted pulverized fuel firing system. The objective of this program is to demonstrate the achievement of lower load by improved flame stabilization and therefore lower operating costs in a full-scale field installation at coal-fired electric utility. GE’s Plasma Ignition and Combustion Stabilization System is designed to operate continuously to support low load operation. With the plasma on, the flame will be attached and stable, removing the firing system as a limitation to low load operation. In addition, GE’s exclusively from ABENZ company licensed AC based technology has a 90+% system efficiency compared to all other systems at which are DC and operate with ~75% efficiency. Plant operating costs are lowered by eliminating use of expensive support fuel as well as the ability to operate at lower loads. The utilities’ ability to better match the demand curve will result in significant savings. Maintenance is lower for an AC system than a DC system as it operates at lower current. This eliminates the need for a demineralized cooling water system and provides longer electrode life which translates into both material and labor savings. It is the objective of GE to not only demonstrate the additional low load achievable with a plasma system after best achievable tuning, sensor and software approach has been exhausted, but also the increased stability of the flame at all loads with plasma assistance as well as cost savings at all low loads using plasma instead of oil. Upon successful completion of this project, GE will have sufficient field experience to rapidly deploy the Plasma Technology. The project objectives were achieved through the implementation of plasma ignitor technology at PacifiCorp Hunter Station Unit 3. A plasma ignitor system was retrofitted on ten wall-fired burners, Mill 3-4 combustion system. The Plasma Ignitors installed at Hunter proved that this GE technology is a direct and complete replacement for the original oil ignitors. The Hunter Unit 3 burner management system allows the plasma system to be used in all applications that originally required oil to be burned. This includes any time the Mill 3-4 is started or stopped for any reason including boiler starts, load changes, and low load support.
Olympus System Backplane Definition
The purpose of this document is to define the backplane of the Olympus firing system, a modular system based on SpaceWire communication between modules. The backplane provides the connection between the modules, controller (embedded in the front module), the SpaceWire router, and an alternative switch. Those connections include SpaceWire links, interlocks, a key, a dead-man switch (DMS)/charge, timing lines, power distribution, geographical addresses, and communication to the human-machine interface (HMI). This backplane is based on the VMEBus International Trade Association (VITA) 46 Specification (VPX) and OpenVPX standards for a 3U backplane. Unless otherwise specified, those standards apply for signal definitions and mechanical specifications.
Fire–precipitation interactions amplify the quasi-biennial variability in fires over southern Mexico and Central America
Fires have great ecological, social, and economic impact. However, fire prediction and management remain challenges due to a limited understanding of their roles in the Earth system. Fires over southern Mexico and Central America (SMCA) are a good example of this, greatly impacting local air quality and regional climate. Here we report that the spring peak (April–May) of fire activities in this region has a distinct quasi-biennial signal based on multiple satellite datasets measuring different fire characteristics. The variability is initially driven by quasi-biennial variations in precipitation. Composite analysis indicates that strong fire years correspond to suppressed ascending motion and weakened precipitation over the SMCA. The anomalous precipitation over the SMCA is further found to be mostly related to the East Pacific–North Pacific (EP-NP) pattern 2 months prior to the fire season. The positive phase of the EP-NP leads to enhanced precipitation over the eastern US but suppressed precipitation over the SMCA, similar to the spatial pattern of precipitation differences between strong and weak fire years. Meanwhile, the quasi-biennial signals in precipitation and fires appear to be amplified by their interactions through a positive feedback loop at short timescales. Model simulations show that in strong fire years, more aerosol particles are released and transported downstream over the Gulf of Mexico and the eastern US, where suspended light-absorbing aerosols warm the atmosphere and cause the ascending motion of the air aloft. Subsequently, a compensating downward motion is formed over the region of the fire source and ultimately suppresses precipitation and intensifies fires. Statistical analysis shows the different durations of the two-way interaction, where the fire suppression effect of precipitation lasts for more than 20 d, while fire leads to a decrease in precipitation at shorter timescales (3–5 d). This study demonstrates the importance of fire–climate interactions in shaping the fire activities on an interannual scale and highlights how precipitation–fire interactions at short timescales contribute to the interannual variability in both fire and precipitation.
Testing- and Model- Based Optimization of Coal-fired Primary Heater Design for Indirect Supercritical CO 2 Power Cycles (Final Scientific and Technical Report)
The overall objective of this project was to perform the R&D necessary to mitigate the risk associated with the design of a primary heat exchanger for a solid-fired combustion system coupled with an indirect-fired closed-loop Brayton Cycle utilizing supercritical CO 2 . The key technological hurdle was the coupling of a solid-fuel firing system with the primary heater, which poses a singular challenge, which is the management of burner performance and operational conditions in a way to manage heat exchanger tube metal temperatures and temperature ramp rates in the absence of fluid phase change on the inside of the tubes. We designed and built the first ever pseudo power system employing a simple recuperated supercritical CO 2 closed-loop Brayton Cycle coupled to a solid-fuel fired system. Advanced coupled CFD and process modeling were used to design the primary heat exchanger (PHX), which consisted of both radiative and convective sections, to limit tube metal temperatures resulting from the heat release profile of the solid fuel flame near the radiative tubes. The heat exchanger was designed to produce finished CO 2 temperatures of 600 °C a pressure of 20.7 MPa and CO 2 flow of 5.5 kg/s. The constructed PHX was capable of 1.2 MWth heat uptake. During design of the PHX, the modeling showed that most variables influencing flame shape (burner stoichiometric ratio and register velocities and swirl) were not suitable to manage heat flux to the metal surfaces. This is because they substantially increased adiabatic flame temperature through the influence of localized stoichiometric ratio. Excess air and firing rate were the two most powerful variables that could be used to control tube surface temperatures. The coupled system was operated for a total of 407 hours, with the longest continuous run of 248 hours. For 62% of the operational time, the unit was unmanned and in automatic control. The fuels used for the testing included natural gas, two Utah Bituminous coals, woody biomass, and bagasse. During the testing we were able to verify the 1.2 MWth heat uptake and we operated at a finished CO 2 temperature of 607 °C and a pressure of 20.3 MPa simultaneously. The real-time corrosion rate of the Super 304H tube CO 2 surface in the region of the radiative section of the PHX were measured, at an approximate temperature of 550 °C. The two key variables related to corrosion rate are the pressure and flow rate of the CO 2 . A technoeconomic analysis was performed at a scale of 120 MWE. The updated analysis showed that the efficiency of an sCO 2 power producing plant will be related to the pressure drop of the PHX.
Evaluation of the energy balance of chemical looping combustion of solid fuels using CuO-based oxygen carriers
Chemical looping combustion (CLC) can inherently capture the CO2 generated during thermal energy production. When using CuO-based oxygen carriers, the reactions in both the fuel reactor (FR) and air reactor (AR) are exothermic, facilitating autothermal operation. To prevent the oxygen carrier from becoming agglomerated while ensuring a sufficient oxygen release rate, it is necessary to predict the FR temperature and remove an appropriate amount of heat from the AR when burning high-rank fuels. Here in this work, the energy balance of a CuO-based CLC system firing various solid fuels (biomass, coal, and petroleum coke) was investigated by establishing a thermodynamic model using FactSage. The energy distribution characteristics of the FR were quantified based on a virtual five-step thermodynamic sequence. The effects of fuel properties, oxygen carrier properties, and operating conditions on the energy balance were evaluated systematically. The results indicate that the temperature difference between the FR and AR is not very sensitive to the heating value of the fuel, while the CuO loading of the oxygen carrier, the heat capacity of the support material, and the flow rate of the fluidizing gas have significant impact. The insights obtained in this work will help improve the design and heat management of CLC.
Satellite-based aerosol optical depth estimates over the continental U.S. during the 2020 wildfire season: Roles of smoke and land cover
Wildfires produce smoke that can affect an area >1000 times the burn extent, with far-reaching human health, ecologic, and economic impacts. Accurately estimating aerosol load within smoke plumes is therefore crucial for understanding and mitigating these impacts. We evaluated the effectiveness of the latest Collection 6.1 MODIS Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm in estimating aerosol optical depth (AOD) across the U.S. during the historic 2020 wildfire season. We compared satellite-based MAIAC AOD to ground-based AERONET AOD measurements during no-, light-, medium-, and heavy-smoke conditions identified using the Hazard Mapping System Fire and Smoke Product. This smoke product consists of maximum extent smoke polygons digitized by analysts using visible band imagery and classified according to smoke density. We also examined the strength of the correlations between satellite- and ground-based AOD for major land cover types under various smoke density levels. MAIAC performed well in estimating AOD during smoke-affected conditions. Correlations between MAIAC and AERONET AOD were strong for medium- (r = 0.91) and heavy-smoke (r = 0.90) density, and MAIAC estimates of AOD showed little bias relative to ground-based AERONET measurements (normalized mean bias = 3 % for medium, 5 % for heavy smoke). During two high AOD, heavy smoke episodes, MAIAC underestimated ground-based AERONET AOD under mixed aerosol (i.e., smoke and dust; median bias = −0.08) and overestimated AOD under smoke-dominated (median bias = 0.02) aerosol. MAIAC most overestimated ground-based AERONET AOD over barren land (mean NMB = 48 %). Our findings indicate that MODIS MAIAC can provide robust estimates of AOD as smoke density increases in coming years. Increased frequency of mixed aerosol and expansion of developed land could affect the performance of the MAIAC algorithm in the future, however, with implications for evaluating wildfire-associated health and welfare effects and air quality standards.
Dynamic Simulation of a Sub-Critical Coal Fired Power Plant
In order to address the demanding operating conditions for remaining coal-fired power plants, a dynamic model and a suite of tools have been developed for studying load cycling and to find optimization opportunities. A sub-critical steam cycle power plant was modeled in a flow-sheet modeling tool, APROS™. The model represented the firing system, economizer, evaporator, superheat, and reheat systems. Four loads from 100% TMCR to 25% TMCR were calibrated and tested such that low-to-high cycling could be studied. The model was run through various load cycles; one of which is presented here. This modeling is a prototype for general use in developing cutting edge controls products and for maximizing economic, low-emissions, and efficient operation of the existing coal power fleet.
A Supercritical CO2 Power Cycle Demonstration Unit for the Development of Future Thermal Power Generation Technologies
Future plans for the 1.5 MWth solid fuel fired system with sCO2 power cycle at Utah San Rafael Energy Lab
Automatic Rural Road Centerline Detection and Extraction from Aerial Images for a Forest Fire Decision Support System
To effectively manage the terrestrial firefighting fleet in a forest fire scenario, namely, to optimize its displacement in the field, it is crucial to have a well-structured and accurate mapping of rural roads. The landscape’s complexity, mainly due to severe shadows cast by the wild vegetation and trees, makes it challenging to extract rural roads based on processing aerial or satellite images, leading to heterogeneous results. This article proposes a method to improve the automatic detection of rural roads and the extraction of their centerlines from aerial images. This method has two main stages: (i) the use of a deep learning model (DeepLabV3+) for predicting rural road segments; (ii) an optimization strategy to improve the connections between predicted rural road segments, followed by a morphological approach to extract the rural road centerlines using thinning algorithms, such as those proposed by Zhang–Suen and Guo–Hall. After completing these two stages, the proposed method automatically detected and extracted rural road centerlines from complex rural environments. This is useful for developing real-time mapping applications.
Handbook for Performing Hydrocarbon Fuel Fires in XTF For Fast-Heat System Level Tests
This document serves to provide information on all aspects of a system level thermal qualification test including a description of the setup and conduct of a full system fuel fire test in the Thermal Test Complex (TTC) Crosswind Test Facility (XTF). This might be referred to as a “handbook” for future tests. This information is intended to assist technologists and test directors in performing these types of tests in the future.
Simultaneous Design and Operation of a Coal-Fired Hybrid Energy System with Integrated Thermal Energy Storage
This final report describes novel capabilities developed as part of DISPATCHES, Design Integration and Synthesis Platform to Advance Tightly Coupled Hybrid Energy Systems, for designing hybrid energy systems (HES) a.k.a. integrated energy systems (IES) in the context of a larger electricity market. Capabilities are demonstrated on a case study with fossil-based power coupled to a molten salt thermal energy storage system.