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Bayham, Samuel

Publications and source records attributed to Bayham, Samuel.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Abstract for CRADA between NETL and Praxair, Inc. (AGMT-0879)

Praxair is interested in evaluating chemical looping technology for industrial gas production. Recent advances in oxygen carrier materials have sparked Praxair’s interest in this technology. Praxair has defined process schemes that leverage recent advances in chemical looping technology. NETL has developed expertise/capabilities in several aspects of chemical looping technology including oxygen carrier materials suitable for different chemical looping reactions, moving/fluidized bed reactors to carry out chemical looping reactions, bench and pilot scale testing, attrition measurement, and reactor modeling. Praxair and NETL will evaluate the potential of chemical looping technology based on oxygen carrier materials recommended by NETL in two phases. Phase 1 will focus on a preliminary technoeconomic feasibility assessment by making assumptions for performance of chemical looping reactors, and Phase 2 will focus on experimental tests as well as detailed modeling to update the assumptions and technoeconomic assessment.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Operation of a 50-kW th chemical looping combustion test facility under autothermal conditions

The United States Department of Energy is developing transformational fossil fuel combustion technologies that result in more efficient power cycles and/or substantial reductions in GHG emissions. Chemical Looping Combustion (CLC) has the potential to achieve a lower cost of electricity than a supercritical pulverized coal power plant with an amine absorption system. Although the concept and research on chemical looping has a long history, CLC has numerous technical issues that must be addressed prior to a commercial debut. This effort is directed toward the following major issues for CLC: (1) demonstrating continuous solids handling, operability, and reactor performance at autothermal conditions and (2) preliminary assessments of oxygen carrier attrition and relative material make-up costs. These are critical issues that should be addressed under realistic conditions prior to directing resources toward larger scale demonstrations. This paper will also describe NETL’s small 50-kWth natural gas circulating CLC test facility located in Morgantown, WV. Despite its small size, this experimental test unit has operated at autothermal conditions for 11 h using a copper-iron-alumina oxygen carrier developed at NETL. Here, this paper will describe the test facility and operating experiences using NETL’s “Gen 2.0” oxygen carrier material. Natural gas conversion to CO2 ranged from 70 to 90% over approximately 75 oxidation-reduction cycles during the autothermal operating period. Estimates for the process specific attrition rate during autothermal operation are also presented. Finally, estimates for the oxygen carrier makeup cost, specific to the NETL process configuration, are several orders of magnitude greater than the NETL target. Future work should focus on reducing the oxygen carrier material cost and improving the attrition resistance of the oxygen carrier material under autothermal test conditions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Pilot Scale Operation and Testing of Syngas Chemical Looping For Hydrogen Production

The Syngas Chemical looping (SCL) process provides efficient and economic means to utilize the abundant fossil reserve of coal. The main problem associated with coal utilization is the CO 2 emissions resulting from its combustion. Even though CO 2 regulation or carbon tax is currently not in place, its enforcement is expected in the near future. Such a greenhouse gas emission control, if adopted in current power plant systems, will drive the efficiency down and increase the cost of electricity, due to the energy and capital-intensive nature of current CO 2 separation techniques. This highlights the need to develop technologies that present a solution to the rising cost of electricity in the future. The integrated gasification combined cycle (IGCC) presents an improvement to the above predicament, but it is capital intensive due to the extensive unit operations involved. The efficiency for a CO 2 capture incorporated IGCC system is around ~32%, resulting in approximately 45% increase in cost of electricity. This is definitely a better path to traverse than the conventional pulverized coal (PC) power plants as it has improved economics and efficiencies accompanied by product flexibility. The SCL process advances the benefits even further when integrated with the IGCC process. The SCL process removes the expensive WGS system and CO 2 separation columns, thereby saving on capital and operational expenses. This integration results in a 12 – 21% increase in efficiency accompanied by a reduction in cost of electricity by 15 – 28%, over conventional IGCC systems. Therefore, SCL process provides the best route to harness the energy from coal. The overall project objective was to construct and operate a syngas chemical looping pilot scale test unit at the NCCC. The project scope of work was divided into 3 phases. In Phase I, cold flow model studies using a 1:1 scale acrylic test unit constructed at Particulate Solids Research, Inc. (PSRI) was successfully completed confirming robust solid flow control is achievable in the non-mechanical system design. In Phase II, the high pressure, high temperature, chemical looping reactor was successfully designed with all necessary equipment and safety instrumentation/controls specified to allow for fabrication, site construction, and assembly to commence in Phase III. In Phase III, the SCL pilot plant was successfully assembled and all necessary functional checks and pre-startup safety reviews completed. During unit commission over the course of 200 hours of testing, operational issues were observed with premix burner used for system startup. With the grants awarded by the National Energy Laboratory (NETL) and the Ohio Development Services Agency (ODSA) under awards DE-FE0023915 and D-14-18, the SCL pilot unit underwent three auxiliary equipment modifications to resolve all of the startup operational issues encountered. The unit was successfully demonstrated with 300+hr continuous operation. Key results obtained include high syngas conversion of 97.95% with 16.03% oxygen carrier conversion in the moving bed reducer and >99% purity H 2 produced from the moving bed oxidizer.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2018

50-kWth methane/air chemical looping combustion tests with commercially prepared CuO-Fe 2 O 3 -alumina oxygen carrier with two different techniques

CuO-Fe 2 O 3 /alumina oxygen carriers were manufactured using two different techniques (i.e., spray drying and wet granulation). The spray drying method produced porous, spherical particles in the range of 100–200 µm. The wet granulation, or tumbling method, produced particles in the range of 200–600 µm. Both batches of material showed good gas conversion and particle durability during tests in NETL’s 50-kWth chemical looping circulating fluidized bed combustor unit at 700–900 °C. No agglomeration was observed, even though the oxygen carrier had a high CuO concentration (30%). The particle losses with 200–600 µm batch were significantly lower than that with the 100–200 µm batch. The oxygen carrier materials in the 200–600 µm range were circulated for approximately 3.1 days in the target temperature range (700–850 °C) and a total of approximately 40 h of chemical looping combustion testing was conducted during that time. The average fuel reactor temperatures ranged from 760 to 815 °C for the chemical looping combustion test periods, and the average air reactor temperature ranged from 840 to 915 °C. The fuel conversion from natural gas to CO 2 ranged from 50 to 80%. Approximately 1.6 h of continuous operation was achieved with no gas preheat and no natural gas augmented heating. During this test period, the average fuel reactor temperature ranged from 780 to 825 °C, the air reactor temperature ranged from 930 to 960 °C, and the natural gas to CO 2 conversion ranged from 50 to 65%. Finally, analysis of the oxygen carrier after the test indicated that there were no significant changes in the particle size or the surface morphology.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Insights into the Adsorption of Carbon Dioxide in the Presence of Water Vapor Utilizing a Low Molecular Weight Polyethylenimine-Impregnated CARiACT Silica Sorbent

Thermogravimetric analysis was employed to investigate the CO 2 and H 2 O adsorption rates and water vapor equilibrium on anhydrous and pre-hydrate linear polyethylenimine (LPEI) sorbent impregnated within a commercially functional CARiACT G10 (HPV) silica support. Water vapor experiments utilizing specific humidity of 2%, 8%, and 16% in contact with an anhydrous PEI sorbent resulted in proportional quantities of water vapor uptake. Subsequently, both anhydrous and pre-hydrated PEI-impregnated sorbents were made available to identical humidified gaseous streams containing a CO 2 concentration of 10% at 60oC. CO 2 capacity increased dramatically in the presence of different levels of humidity. Various kinetic models were systematically employed to interpret the experimental data including single and multiple-step models. The rate data was best represented by a reaction mechanism pathway involving the interplay of CO 2 with PEI-impregnated sorbents exhibited a quick adsorption phase followed by a slow approach to equilibrium. Moreover, a phenomenological rate model was developed to describe the dynamic H 2 O and CO 2 uptakes at specific humidity levels studied. The kinetic study showed good agreement with experimental data. Furthermore, the effects observed during the adsorption and hydration are shown to be complementary to known chemical and physical transformations within the polyethylenimine’s macromolecule.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2017

Operation of the NETL Chemical Looping Reactor with Natural Gas and a Novel Copper-Iron Material

The proposed Clean Power Plan requires CO 2 emission reductions of 30% by 2030 and further reductions are targeted by 2050. The current strategies to achieve the 30% reduction targets do not include options for coal. However, the 2016 Annual Energy Outlook suggests that coal will continue to provide more electricity than renewable sources for many regions of the country in 2035. Therefore, cost effective options to reduce greenhouse gas emissions from fossil fuel power plants are vital in order to achieve greenhouse gas reduction targets beyond 2030. As part of the U.S. Department of Energy’s Advanced Combustion Program, the National Energy Technology Laboratory’s Research and Innovation Center (NETL R&IC) is investigating the feasibility of a novel combustion concept in which the GHG emissions can be significantly reduced. This concept involves burning fuel and air without mixing these two reactants. If this concept is technically feasible, then CO 2 emissions can be significantly reduced at a much lower cost than more conventional approaches. This indirect combustion concept has been called Chemical Looping Combustion (CLC) because an intermediate material (i.e., a metal-oxide) is continuously cycled to oxidize the fuel. This CLC concept is the focus of this research and will be described in more detail in the following sections. The solid material that is used to transport oxygen is called an oxygen carrier material. The cost, durability, and performance of this material is a key issue for the CLC technology. Researchers at the NETL R&IC have developed an oxygen carrier material that consists of copper, iron, and alumina. This material has been tested extensively using lab scale instruments such as thermogravimetric analysis (TGA), scanning electron microscopy (SEM), mechanical attrition (ASTM D5757), and small fluidized bed reactor tests. This report will describe the results from a realistic, circulating, proof-of-concept test that was completed using NETL’s 50kW th circulating Chemical Looping Reactor (CLR) test facility.

01 COAL, LIGNITE, AND PEAT↗