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At least 811 records · Page 45

Residential Ground Source Heat Pumps with Integrated Domestic Hot Water Generation: Performance Results from Long-Term Monitoring

Ground source heat pumps (GSHPs) show great promise as a means to substantially reduce energy consumption in houses. Laboratory test data from manufacturers of these units indicate that using the soil between 6 and 600 ft below the surface of the earth as the thermal energy source or sink gives GSHPs the potential to obtain coefficients of performance (COPs) ranging from 4 to 6 for heating and cooling.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Transport Membrane Condenser for Water and Energy Recovery from Power Plant Flue Gas

The new waste heat and water recovery technology based on a nanoporous ceramic membrane vapor separation mechanism has been developed for power plant flue gas application. The recovered water vapor and its latent heat from the flue gas can increase the power plant boiler efficiency and reduce water consumption. This report describes the development of the Transport Membrane Condenser (TMC) technology in details for power plant flue gas application. The two-stage TMC design can achieve maximum heat and water recovery based on practical power plant flue gas and cooling water stream conditions. And the report includes: Two-stage TMC water and heat recovery system design based on potential host power plant coal fired flue gas conditions; Membrane performance optimization process based on the flue gas conditions, heat sink conditions, and water and heat transport rate requirement; Pilot-Scale Unit design, fabrication and performance validation test results. Laboratory test results showed the TMC system can exact significant amount of vapor and heat from the flue gases. The recovered water has been tested and proved of good quality, and the impact of SO 2 in the flue gas on the membrane has been evaluated. The TMC pilot-scale system has been field tested with a slip stream of flue gas in a power plant to prove its long term real world operation performance. A TMC scale-up design approach has been investigated and an economic analysis of applying the technology has been performed.

20 FOSSIL-FUELED POWER PLANTS↗

Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses (2012 Annual Summary Report)

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC 2007a) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs), with the results submitted to the U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE 1999a, 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2012. This annual summary report presents data and conclusions from the FY 2012 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (RD) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and RD activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2012 include the following: Release of a special analysis for the Area 3 RWMS assessing the continuing validity of the PA and CA; Development of a new Area 5 RWMS closure inventory estimate based on disposals through FY 2012; Evaluation of new or revised waste streams by special analysis; and Development of version 4.114 of the Area 5 RWMS GoldSim PA model. The Area 3 RWMS has been in inactive status since July 1, 2006, with the last shipment received in April 2006. The FY 2012 review of operations, facility design, closure plans, monitoring results, and RD results for the Area 3 RWMS indicates no changes that would impact PA validity. A special analysis using the Area 3 RWMS v2.102 GoldSim PA model was prepared to update the PA results for the Area 3 RWMS in FY 2012. The special analysis concludes that all performance objectives can be met and the Area 3 RWMS PA remains valid. There is no need to the revise the Area 3 RWMS PA. Review of Area 5 RWMS operations, design, closure plans, monitoring results, and RD activities indicates no significant changes other than an increase in the inventory disposed. The FY 2012 PA results, generated with the Area 5 RWMS v4.114 GoldSim PA model, indicate that there continues to be a reasonable expectation of meeting all performance objectives. The results and conclusions of the Area 5 RWMS PA are judged valid, and there is no need to the revise the PA. A review of changes potentially impacting the CAs indicates that no significant changes occurred in FY 2012. The continuing adequacy of the CAs was evaluated with the new models, and no significant changes that would alter CA results or conclusions were found. The revision of the Area 3 RWMS CA, which will include the Underground Test Area source term (Corrective Action Unit [CAU] 97), is scheduled for FY 2024, following the completion of the Yucca Flat CAU 97 Corrective Action Decision Document/Corrective Action Plan in FY 2016. Inclusion of the Frenchman Flat CAU 98 results in the Area 5 RWMS CA is scheduled for FY 2016, pending the completion of the CAU 98 closure report in FY 2015. Near-term RD efforts will focus on continuing development of the Area 3 and Area 5 RWMS GoldSim PA/CA and inventory models.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

In-Situ Acoustic Measurements of Temperature Profile in Extreme Environments

A gasifier’s temperature is the primary characteristic that must be monitored to ensure its performance and the longevity of its refractory. One of the key technological challenges impacting the reliability and economics of coal and biomass gasification is the lack of temperature sensors that are capable of providing accurate, reliable, and long-life performance in an extreme gasification environment. This research has proposed, demonstrated, and validated a novel approach that uses a noninvasive ultrasound method that provides real-time temperature distribution monitoring across the refractory, especially the hot face temperature of the refractory. The essential idea of the ultrasound measurements of segmental temperature distribution is to use an ultrasound propagation waveguide across a refractory that has been engineered to contain multiple internal partial reflectors at known locations. When an ultrasound excitation pulse is introduced on the cold side of the refractory, it will be partially reflected from each scatterer in the US propagation path in the refractory wall and returned to the receiver as a train of partial echoes. The temperature in the corresponding segment can be determined based on recorded ultrasonic waveform and experimentally defined relationship between the speed of sound and temperature. The ultrasound measurement method offers a powerful solution to provide continuous real time temperature monitoring for the occasions that conventional thermal, optical and other sensors are infeasible, such as the impossibility of insertion of temperature sensor, harsh environment, unavailable optical path, and more. Our developed ultrasound system consists of an ultrasound engineered waveguide, ultrasound transducer/receiver, and data acquisition, logging, interpretation, and online display system, which is simple to install on the existing units with minimal modification on the gasifier or use with new units. This system has been successfully tested with a 100 kW pilot scale down flow oxyfuel combustor, capturing in real time temperature changes during all relevant combustion process changes. The ultrasound measurements have excellent agreement with thermo- couple measurements, and appear to be more sensitive to temperature changes before the thermocouples response, which is believed to be the first demonstration of ultrasound measurements segmental temperature distribution across refractories.

47 OTHER INSTRUMENTATION↗

Improvements in Boron Plate Coating Technology for Higher Efficiency Neutron Detection and Coincidence Counting Error Reduction

This informal report presents the measurement data and information to document the performance of the advanced Precision Data Technology, Inc. (PDT) sealed cell boron-10 plate neutron detector that makes use of the advanced coating materials and procedures. In 2015, PDT changed the boron coating materials and application procedures to significantly increase the efficiency of their basic corrugated plate detector performance. A prototype sealed cell unit was supplied to LANL for testing and comparison with prior detector cells. Also, LANL had reference detector slabs from the original neutron collar (UNCL) and the new Antech UNCL with the removable 3He tubes. The comparison data is presented in this report.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Underground Test Area Activity Preemptive Review Guidance Nevada National Security Site, Nevada, Revision 0

Preemptive reviews (PERs) of Underground Test Area (UGTA) Activity corrective action unit (CAU) studies are an important and long-maintained quality improvement process. The CAU-specific PER committees provide internal technical review of ongoing work throughout the CAU lifecycle. The reviews, identified in the UGTA Quality Assurance Plan (QAP) (Sections 1.3.5.1 and 3.2), assure work is comprehensive, accurate, in keeping with the state of the art, and consistent with CAU goals. PER committees review various products, including data, documents, software/codes, analyses, and models. PER committees may also review technical briefings including Federal Facility Agreement and Consent Order (FFACO)-required presentations to the Nevada Division of Environmental Protection (NDEP) and presentations supporting key technical decisions (e.g., investigation plans and approaches). PER committees provide technical recommendations to support regulatory decisions that are the responsibility of the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) and NDEP.

54 ENVIRONMENTAL SCIENCES↗

Air-Source Integrated Heat Pump System Development – Final Report

Between October 2007 and September 2017, Oak Ridge National Laboratory (ORNL) and Lennox Industries, Inc. (Lennox) engaged in a Cooperative Research and Development Agreement (CRADA) to develop an air-source integrated heat pump (AS-IHP) system for the US residential market. The Lennox AS-IHP concept consisted of a high-efficiency air-source heat pump (ASHP) for space heating and cooling services and a separate heat pump water heater/dehumidifier (WH/DH) module for domestic water heating and dehumidification (DH) services. A key feature of this system approach with the separate WH/DH is capability to pretreat (i.e., dehumidify) ventilation air and dedicated whole-house DH independent of the ASHP. Two generations of laboratory prototype WH/DH units were designed, fabricated, and lab tested. Performance maps for the system were developed using the latest research version of the US Department of Energy/ORNL heat pump design model (Rice 1992; Rice and Jackson 2005; Shen et al. 2012) as calibrated against the lab test data. These maps served as the input to TRNSYS (Solar Energy Laboratory et al. 2010) to predict annual performance relative to a baseline suite of equipment meeting minimum efficiency standards in effect in 2006 (i.e., a combination of an ASHP with a seasonal energy efficiency ratio (SEER) of 13 and resistance water heater with an energy factor (EF) of 0.9). Predicted total annual energy savings (based on use of a two-speed ASHP and the second-generation WH/DH prototype for the AS-IHP), while providing space conditioning, water heating, and dehumidification for a tight, well-insulated 2600 ft2 (242 m2) house at three US locations, ranged from 33 to 36%, averaging 35%, relative to the baseline system. The lowest savings were seen at the cold-climate Chicago location. Predicted energy use for water heating was reduced by about 50 to 60% relative to a resistance WH.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Improving Energy Efficiency of Air Separation via Hollow Fiber Sorbents

This report summarizes the work performed under the Department of Energy’s National Energy Technology Laboratory (DOE-NETL) Advanced Energy Systems Program award number DE-FE0026163 Improving Energy Efficiency of Air Separation via Hollow Fiber Sorbents. The overall objective of the project was to develop technology to produce oxygen for use in coal gasification processes at a significantly lower cost than that of the commercial state-of-the-art technology. The focus of the project was development and optimization of hollow fiber sorbents for use in a pressure swing adsorption (PSA) process for producing oxygen from air. The key technical advancement under this program was the development of a hollow fiber sorbent capable of producing oxygen in a PSA process. PSAs produce oxygen by using a beaded zeolite material (typically lithium exchanged zeolites or LiX) that selectively adsorb nitrogen over oxygen. For a fiber to adsorb nitrogen, LiX needed to be integrated into a polymer fiber and then activated at over 350C to remove residual moisture. After screening multiple materials and process techniques, Matrimid/LiX hollow fibers were produced that were able to withstand the activation and had crystalline nitrogen capacity close to pure LiX crystals. The fibers were dual layer fibers with a barrier layer isolating the hollow bore from the LiX embedded layer. The barrier layer was formed from an Ultem® based solution. The hollow bore was intended for encapsulating phase change materials to ensure isothermal PSA operation. Modeling work from the project suggested that the benefits of this additional complexity were marginal, thus the team fabricated non-hollow fibers comprised of Matrimid and LiX. The Matrimid/LiX fibers were loaded into a module and tested on a bench scale PSA unit. The fibers were able to separate oxygen from air, but the purity and recovery were lower than expected and lower than traditional beaded LiX zeolites, although modeling results suggested that the bed sizes for fiber sorbents could be half the size of a beaded LiX bed. Additional work will be needed to understand the shortfall and to produce fiber sorbent modules with performance equal to the targets set for this program. In addition to producing fibers, modeling work was carried out at both the fiber level and process level to guide both fiber sorbent development and to determine the optimal process conditions for a PSA using fiber sorbents. A 2D hollow fiber model was developed in gPROMS Model Builder. This model was based on literature data for mass transfer and other parameters. This model used a basic single bed PSA process to determine important fiber properties and process conditions for achieving high oxygen recovery. The preliminary 2D fiber model was a valuable tool, however, for step-out technologies, such as a PSA process with fiber sorbents, intelligent optimization and plant control was needed to effectively determine minimum power designs. Therefore, a gPROMS Process Builder-based optimization tool was developed with an “Automated Cycle Optimizer” model that was able to determine optimal cycle conditions for a fiber sorbent PSA. The results from the optimizer were used in the final power analysis. Flow sheet analysis and techno-economic analysis (TEA) was carried out to determine a lower power solution versus the baseline case. The original project scope suggested that the fiber sorbent PSA could be used to debottleneck a cryogenic air separation plant (cryo-ASU) with the combined plant having lower power than a standalone cryo-ASU. However, early flowsheet analysis showed that the PSA/cryo-ASU concept would not lead to a lower power solution. However, further flowsheet analysis suggested that an oxygen PSA combined with a nitrogen PSA could have lower power versus state-of-the-art air separation technology. Work concluded with the TEA showing a fiber sorbent oxygen PSA combined with an advanced nitrogen PSA could be up to 8% lower power versus the base case cryo-ASU. Overall, there is significant potential remaining for the zeolite hollow fiber sorbent concept, and this project successfully identified -- and ultimately remedied -- many technical challenges associated with scale-up.

01 COAL, LIGNITE, AND PEAT↗

Catalytic Bio-crude Production in a Novel, Short-Contact Time Reactor

RTI has developed a catalytic fast pyrolysis (CFP) process to produce biomass-based hydrocarbon replacement fuels. From a technology perspective, this advanced biofuels process produces liquid transportation fuels that can leverage capital expenditures in the existing petroleum distribution infrastructure. From a business perspective, this technology does not face potential market limitations caused by oxygenate blend limitations for light duty vehicle applications. A promising catalyst has been developed with excellent potential for deoxygenation to produce a hydrocarbon-rich biocrude that is more suitable for upgrading with traditional hydroprocessing technology. The role of the catalyst is to control the chemistry during biomass pyrolysis to produce a biocrude in a single step that has lower oxygen content and is more thermally stable than conventional biomass fast pyrolysis oil. Catalyst properties are optimized to minimize gas and coke production and improve catalytic deoxygenation and biocrude yields. Results from this project have demonstrated that biocrudes from catalytic fast pyrolysis contain <20 wt% oxygen, with the organic fraction as low as 12% oxygen. These oxygen numbers are > 50% lower compared to traditional fast pyrolysis oils. The biocrude produced from our CFP process can be upgraded to gasoline range hydrocarbons. A very conservative approach for upgrading included a preliminary stabilization step followed by a hydroprocessing step. The oxygen content in the upgraded product was decreased by 97% (to less than 3wt %) from the oxygen content of the biocrude sample. Additionally, the acid content was reduced by 99% from the acid content of the biocrude sample. In an optimized integrated process, the CFP step and the hydroprocessing (upgrading) step need to be carefully balanced to maximize the input biomass energy that is recovered in the finished biofuels. Hydrogen utilization and carbon recovery during both catalytic biomass pyrolysis and biocrude upgrading need to be optimized to maximize energy recovery in the finished biofuel. A nominal 1 ton per day (TPD) catalytic biomass pyrolysis system was designed based on the laboratory experimental data. The system was designed to achieve the short residence times (0.5–2 sec) and high heat transfer rates required for maximum liquid biocrude yields while optimizing process integration to maintain catalyst activity by continuous regeneration. The catalytic biomass pyrolysis reactor is a continuously circulating single-loop transport reactor design that is flexible enough to allow sensitivity studies around temperature, residence time, biomass feed rate, and catalyst-to-biomass ratio (i.e., catalyst circulation rate) for process optimization. For a nominal 100 lb/hr feed rate of dry biomass, the products include ~25 lb/hr char and coke, ~20 lb/hr permanent gases, and ~55 lb/hr condensable vapors. Pyrolysis temperatures are 350–600°C, and the system is operated close to ambient pressure. Production of the catalyst developed within the project was scaled up to provide enough material (200kg) for bench-scale testing. The 1TPD bench-scale unit was fabricated, installed and commissioned with this project. Biocrude samples from wood were produced in this unit with the CFP catalyst with material balance > 90%. The intermediate biocrude yields and chemical composition compare well with previous laboratory results and a hydroprocessing strategy for upgrading the resulting biocrude was developed. The experimental results obtained within this project were used to develop a process model for a 2000 TPD commercial facility. Detailed flow sheets were developed for all major unit operations in the process and provided a basis for an economic analysis to develop capital and operating costs. Estimates of the biofuel production costs were used to develop internal rates of return for the yields and compositions measured for the current state of technology at the end of this project and for the yields anticipated for an optimized (nth plant) scenario as additional process improvements are made.

09 BIOMASS FUELS↗

Assessing the Vulnerability of Unmanned Aircraft Systems to Directed Acoustic Energy

The increasingly large payloads of Unmanned Aircraft Systems (UASs) are exponentially increasing the threat to the nuclear enterprise. Current mitigation using RF interference is effective, but not feasible for fully autonomous systems and is prohibited in many areas. A new approach to UAS threat mitigation is needed that does not create radio interference but is effective against any type of vehicle. At the present time there is no commercial counter-UAS system that directly assaults the mems gyros and accelerometers in the Inertial Measurement Unit on the aircraft. But lab testing has revealed resonances in some IMUs that make them susceptible to moderate amplitude acoustic monotones. Sandia's energetic materials facility has enabled a quick and thorough exploration of UAS vulnerability to directed acoustic energy by using intense acoustic impulses to destabilize or down a UAS. We have: 1) detonated/deflagrated explosive charges of various sizes; 2) accurately measured impulse pressure and pulse duration; 3) determined what magnitude of acoustic insult to the IMU disrupts flight and for how long and; 4) determined if the air blast/shock wave on aircraft/propellers disrupts flight.

42 ENGINEERING↗

bifiPV2020 Bifacial Workshop: A Technology Overview

The virtual bifiPV Workshop was held in July 2020 to provide the solar industry with a forum for sharing and discussing research into bifacial photovoltaic (PV) technology. This report outlines major insights from the workshop to give the reader an overview of the latest developments in bifacial PV technology worldwide, from the lab to the field. Citations are drawn from this workshop unless otherwise noted, with all proceedings available online at bifipvworkshop. com. Presentations for the bifiPV2020 Workshop focused on the following areas: bifacial power plant modeling and simulation, albedo improvements, the development of encapsulants, the durability and reliability of current bifacial technologies, performance comparisons between glass-glass and glass-transparent backsheet configurations, the future of passivated emitter and rear contact (PERC) solar cells, and the growing adoption of n-type solar cells. With 650 GW total PV installed worldwide and 1 TW to come very soon, PERC is now the standard PV cell type produced en masse. However, it is already reaching 23% efficiency, the upper limit for this type of technology. PV modules breaking the 0.5-kW barrier are starting to appear, and the costs of standard PERC technology are already below 0.2 USD/Wp. In 2019, five GW of bifacial PV were installed worldwide. In 2020, the majority of bifacial installations are expected to be located in the United States, China, and Middle East and North Africa (MENA) states. N-type bifacial technologies are becoming increasingly viable and have huge potential to dominate the market in the coming years. With bifacial technology mounted on horizontal single-axis trackers (HSAT), bids below 10 USD/MWh will soon be observed in the MENA region, and later in Chile and the United States. Factory audits and reliability testing can reduce field failures by helping buyers to select producers that follow rigorous quality assurance and quality control processes.

14 SOLAR ENERGY↗

bifiPV2020 Bifacial Workshop: A Technology Overview

The virtual bifiPV Workshop was held in July 2020 to provide the solar industry with a forum for sharing and discussing research into bifacial photovoltaic (PV) technology. This report outlines major insights from the workshop to give the reader an overview of the latest developments in bifacial PV technology worldwide, from the lab to the field. Citations are drawn from this workshop unless otherwise noted. Presentations for the bifiPV2020 Workshop focused on the following areas: bifacial power plant modeling and simulation, albedo improvements, the development of encapsulants, the durability and reliability of current bifacial technologies, performance comparisons between glass-glass and glass-transparent backsheet configurations, the future of passivated emitter and rear contact (PERC) solar cells, and the growing adoption of n-type solar cells. With 650 GW total PV installed worldwide and 1 TW to come very soon, PERC is now the standard PV cell type produced en masse. However, it is already reaching 23% efficiency, the upper limit for this type of technology. PV modules breaking the 0.5-kW barrier are starting to appear, and the costs of standard PERC technology are already below 0.2 USD/Wp. In 2019, five GW of bifacial PV were installed worldwide. In 2020, the majority of bifacial installations are expected to be located in the United States, China, and Middle East and North Africa (MENA) states. N-type bifacial technologies are becoming increasingly viable and have huge potential to dominate the market in the coming years. With bifacial technology mounted on horizontal single-axis trackers (HSAT), bids below 10 USD/MWh will soon be observed in the MENA region, and later in Chile and the United States. Factory audits and reliability testing can reduce field failures by helping buyers to select producers that follow rigorous quality assurance and quality control processes.

14 SOLAR ENERGY↗

PMK 1000 cone-socket ventilator fittings force testing to ISO 5356-1:2015 Standard

This memo summarizes the results of verification tests on a cone-socket fitting to the ISO 5356-1:2015 standard, annexes B and F. The components were found to meet requirements holding 50N tensile force and more than 35 N-cm of torque for 10 seconds without separating at 35°C with a fresh socket. Humidity control was unavailable; consequently, humidity was significantly lower than the values in the ISO standard. Several repeat tests of the fitting with force, torque, and time excursions give us confidence that the fittings perform suitably to the ISO standard. Force overload tests suggest that the samples will disengage under tension at around 69 N, while torque overload tests under a force of 50 N will fail at 79 N-cm of torque. If repeated tests are performed on the same component, the socket can deform and lead to the connection failing the standard requirements. However, such failures only occur with repeated testing, and the gripping of such units can be modified so that they pass the standard. This observation demonstrates that socket gripping is responsible for those failures and would not be a problem in application.

42 ENGINEERING↗

SECARB Second Injection Period Reservoir Modeling Report

The Southeast Carbon Sequestration Partnership Phase III Anthropogenic Test at Citronelle Field is the United States’ largest CO 2 capture and transportation, injection, storage and monitoring project using CO 2 derived from a coal-fired power station. The project represents a U.S. Department of Energy research and development initiative designed to demonstrate deep underground injection and containment of 100,000 tonnes or more of anthropogenic-source CO 2 . A series of reservoir modeling runs will be performed during the pre-injection, injection, and post-injection phases of the project and will be used to predict plume migration and areal extent. Pressure, temperature, and downhole measurements (seismic, fluid and logging), all data collected as a part of the monitoring program, are utilized as reservoir performance parameters to tune the existing geophysical and geochemical simulation models.

01 COAL, LIGNITE, AND PEAT↗

Gradient Amine Sorbents for Low Vacuum Swing CO 2 Capture at Ambient Temperature

The growing concerns over CO 2 emissions have led to the development of various methods for CO 2 capture. CO 2 capture by amine-based sorbents has been achieved by temperature (thermal) swing adsorption (TSA) process, pressure swing adsorption (PSA) process, and temperature pressure or vacuuming swing adsorption (TPSA or TVSA) process for CO 2 capture. Amine sorbents for energy-efficient TSA, PSA, VSA, TPSA or TVSA CO 2 capture should possess a capability which allow adsorbed CO 2 to desorb and amine sorbent to be regenerated at low temperatures or low vacuums. Development of such amine sorbents would significantly decrease energy consumption and sorbent degradation during the regeneration step. The objective of this project is to develop a low vacuum swing adsorption (VSA) process for the capture of CO 2 from air. The focus is on the development of amine sorbent which allows CO 2 to adsorb in the form of weakly adsorbed CO 2 . The weakly adsorbed CO 2 species can be collected from the sorbent by applying a low vacuum at ambient temperature. Specifically, no heating (i.e., thermal energy) is needed for regeneration of amine sorbents. This novel sorbent allows VSA to be operated at ambient temperature without a significant energy demand. This process eliminates the energy-intensive heating and cooling process in temperature swing adsorption (TSA) process. Ambient temperature operation could prolong the lifetime of sorbent and minimize the maintenance cost. Extensive sorbent studies with in-situ infrared spectroscopy have revealed the modifications of conventional amine sorbents with additives can increase the fraction of weakly adsorbed CO 2 . The amine sorbents with loaded CO 2 can be regenerated in part by the following approaches: (i) mild heating to temperatures below 70 °C, (ii) flowing purging gas over modified amine sorbents at temperatures below 40 °C, (iii) vacuuming at pressure below 0.2 atm and temperatures below 40 °C. The performance of these modified amine sorbents has been tested in a 60 grams VSA unit at ambient temperatures. The results show that weakly adsorbed CO 2 which can be desorbed from modified amine sorbents with purging gas at 100 cc/min can also be evacuated at a vacuum of 1 psia at room temperature. A preliminary techno- economic analysis indicates the major cost of the VSA process with modified amine sorbents stems from the operation of vacuum pumps. Thus, developing an excellent sealing with minimum leakage for the VSA unit is the most critical task for further the development of this VSA technology.

36 MATERIALS SCIENCE↗

Calculating the Effects of Solids Input and Removal as a Temperature Control in the Advanced Scale Up Reactor Experiment (ASURE) Facility at NETL Using Aspen

The Advanced Scale Up Reactor Experiment (ASURE) facility at NETL is being designed to be a fuel-flexible multi-purpose reactor that can be used for pyrolysis/gasification or evaluation of other high pressure “circulating fluidized bed” (CFB) chemical processes. The initial system design calculations for pyrolysis/gasification are presented in this work showing the expected performance of the ASURE facility when used as a biomass conversion reactor. Several other areas of application include gasification of any carbonaceous fuel including biomass, coal, plastics, and other waste materials. The reactor can therefore be used to produce SYNGAS of various compositions and hydrogen as well as other high value chemicals resulting from a typical tuned gasification process. This paper discusses an ASPEN model of the facility, focusing on the riser of the CFB reactor and the solids recirculation loop. The ASPEN model divides the riser into two sections. A bottom section which receives ash, char and sand which have been recirculated from a return loop. In this section an inert fluidization gas, (N2 or CO2), is introduced which acts as the primary mover of the solids through the system. The bottom section is equipped with a restricted air feed so that the recirculated char can be partially oxidized. This oxidation process along with the inventory of recirculating sand are used to effectively control the temperature in the following two chemical conversion sections of the reactor which are the pyrolysis zone followed by a tar cracking zone. Fresh fuel is added to the pyrolysis zone and undergoes drying and devolatilization. The products ash, char, volatile matter, and water vapor exit the pyrolysis zone and enter the reaction block for tar cracking. Steam and CO2 gasification reactions will be incorporated into the tar cracking zone, however at the design operating temperature, conversion from these reactions is expected to be essentially zero. The unit when completed in 2026 will test mixtures of biomass, plastics, and waste coal. This presentation discusses the basic ASPEN engineering design model for this project and provides preliminary sensitivity studies to determine how the various parts of the reactor will perform.

ASSURE↗

An Overview of the Source Physics Experiment at the Nevada National Security Site (SPE-N)

Understanding the changes in seismic energy as it travels from the near field to the far field is the ultimate goal in monitoring for explosive events of interest. This requires a clear understanding of explosion phenomenology as it relates to seismic, infrasound, and acoustic signals. Although there has been much progress in modeling these phenomena, this has been primarily based in the empirical realm. As a result, the logical next step in advancing the seismic monitoring capability of the United States is to conduct field tests that can expand the predictive capability of the physics-based modeling currently under development. The Source Physics Experiment at the Nevada National Security Site (SPE-N) is the first step in this endeavor to link the empirically based with the physics-based modeling. This is a collaborative project between National Security Technologies (NSTec), Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratories (SNL), the Defense Threat Reduction Agency (DTRA), and the Air Force Technical Applications Center (AFTAC). The test series require both the simple and complex cases to fully characterize the problem, which is to understand the transition of seismic energy from the near field to the far field; to understand the development of S-waves in explosives sources; and how anisotropy controls seismic energy transmission and partitioning. The current series is being conducted in a granite body called the Climax Stock. This location was chosen for several reasons, including the fairly homogenous granite; the location of previous nuclear tests in the same rock body; and generally the geology has been well characterized. The simple geology series is planned for 7 shots using conventional explosives in the same shot hole surrounded by Continuous Reflectometry for Radius vs. Time Experiment (CORRTEX), Time of Arrival (TOA), Velocity of Detonation (VOD), down-hole accelerometers, surface accelerometers, infrasound, and a suite of seismic sensors of various frequency bands from the near field to the far field. This allows for the use of a single test bed in the simple geology case instead of multiple tests beds to obtain the same results. The shots are planned at various depths to obtain a Green’s function, scaled-depth of burial data, nominal depth of burial data and damage zone data. SPE1-N was conducted in May 2011 as a 220 lb (100 kg) TNT equivalent calibration shot at a depth of 180 ft (55 m). SPE2-N was conducted in October 2011 as a 2200 lb (1000 kg) TNT equivalent calibration shot at a depth of 150 ft (46 m). SPE3-N was conducted in July 2012 as a 2200 lb (1000 kg) TNT equivalent calibration shot at a depth of 150 ft (46 m) in the damaged zone. Over 400 data channels were recorded for each of these shots and data recovery was about 95% with high signal to noise ratio. Once the simple geology site data has been utilized, a new test bed will be developed in a complex geology site to test these physics based models. Ultimately, the results from this project will provide the next advances in the science of monitoring to enable a physics-based predicative capability.

Source record↗