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Surface magnetic enhancement for coal cleaning

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibility of minerals have been established in Phase I study. The application of the results on coal cleaning is in progress in the Phase II study. The task in Phase II study for coal selection, preparation, and characterization is completed in this reporting period. The optimization of adsorption conditions for {minus}48 mesh ROM coals and flotation concentrates is about completed. Experiments have shown that successful coal cleaning can be obtained with this magnetizing reagent approach. The task to adapt the approach to various processing schemes is just initiated.
Date: January 1, 1989
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase 1 study. The application of the results on coal cleaning for the Phase 2 study is completed this quarter. Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals have been investigated to determine the most effective way of using the magnetizing method for coal cleaning. The results show that the best separation performance is obtained on finely ground coals. Up to 91% ash reduction (from 22% to 3.3% ash content) and 93% pyritic sulfur reduction at 70% BTU recovery can be obtained with the magnetizing approach when Illinois No. 6 coal is processed at 90% passing 500 mesh. Even at a coarser sizes such as 90% passing 200 mesh, 86% ash reduction and 87% pyritic sulfur reduction with 74% coal TBU recovery can still be obtained. Similar results are obtained for Lower Kittanning and Pocahontas coal.
Date: January 1, 1990
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The progress achieved during this quarter includes the ten months shelf life study of magnetizing reagent, the effect of cation regulators on minerals and coals, the combination effect of depressant and activator on the adsorption of magnetizing reagent, optimum magnetite size for magnetizing reagent, and the magnetic field strength for separating magnetic enhanced minerals. The work is generally on schedule with the original plan. The Phase I study (a fundamental study) is nearly completed. Selective conditions for adsorbing magnetizing reagent on minerals have been identified. The work for the next quarter will be mainly on the Phase II study. Coal will be selected, procured, characterized, and processed.
Date: January 1, 1989
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase I study. The application of the results on coal cleaning is in progress in the Phase II study. Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals are investigated during this reporting period to determine the most effective way of using the magnetizing method for coal cleaning. The results show that the best separation performance is obtained on finely ground coals. Up to 91% ash reduction (from 22% to 3.3% ash content) at 70% coal recovery can be obtained with the magnetizing approach when Illinois No. 6 coal is processed at 90% passing 500 mesh. Even at a coarser sizes such as 90% passing 200 mesh, 86% ash reduction with 71% coal recovery can still be obtained. Although the results are probably better than using the froth flotation method, direct comparison tests will be conducted in the next reporting period.
Date: January 1, 1990
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: Phase I study, which investigates the fundamental chemistry and properties of magnetizing reagents, is completed in this reporting period. Phase II study is initiated to apply the results of Phase I study for coal cleaning. Coal samples for Phase II work have been selected, ordered, and received. Processing and characterization of coal samples are in progress. Preliminary tests show that significant ash and sulfur reduction can be obtained with the magnetizing reagent method. The work is slightly behind the schedule due to the delay of coal shipment. Since the coal samples have been received, the schedule will be caught up in the next quarter. The major work for the next quarter will be the processing and characterization of coals and the optimization of magnetizing conditions for each coal.
Date: January 1, 1989
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase I study. The application of the results to study the feasibility for coal cleaning has been completed in the Phase II study. The most effective approach to clean Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals using the magnetizing method has been determined. Phase III study is in progress during this quarter. Experimental work includes the determination of various separation parameters, including the separator and matrix selection, magnetic reagent dosage, particle size, magnetic field intensity, and retention time.
Date: January 1, 1990
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The progress achieved during this quarter includes the reagent shelf life study, the evaluation and selection of magnetizing reagents, an experimental database for activating and depressing the adsorption of magnetizing reagents in the presence of various chemicals, an adsorption regulator investigation, the establishment of a coal surface controlling theory, and a magnetite size effect study for the separation of magnetic enhanced minerals. The work is on schedule with the original plan. Modifications include the addition of a regulator study to help proving the selectivity controlling theory. The fundamentals for applying the magnetizing reagent technology on coal cleaning are generally established during this quarter. Selective magnetic enhancement of minerals through the adsorption of magnetizing reagents has been experimentally proved. The work for the next quarter will be mainly on optimizing the selective adsorption conditions and the continuation on magnetite size effect study.
Date: January 1, 1988
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase I study. The application of the results on coal cleaning is in progress in the Phase II study. Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals have been prepared(simulating the industrial operations) and characterized. The adsorption conditions for {minus}48 mesh ROM coals and flotation concentrates have been optimized. Magnetic separation of the reagent conditioned coals shows that both ash and pyritic sulfur can be significantly reduced. Comparing with the repeated flotation approach for coal cleaning, the magnetizing reagent enhanced magnetic separation method shows better performance on cleaning the flotation concentration at {minus}48 mesh.
Date: January 1, 1989
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning

Description: The program consisted of a fundamental study to define the chemistry for the interactions between magnetic reagent and mineral and coal particles, a laboratory study to determine the applicability of this technology on coal cleaning, and a parameter study to evaluate the technical and economical feasibility of this technology for desulfurization and de-ashing under various processing schemes. Surface magnetic enhancement using magnetic reagent is a new technology developed at the Institute. This technology can be applied to separate pyrite and other minerals particles from coal with a magnetic separation after adsorbing magnetic reagent on the surface of pyrite and other minerals particles. Particles which have absorbed magnetic reagent are rendered magnetic. The adsorption can be controlled to yield selectivity. Thus, the separation of traditionally nonmagnetic materials with a magnetic separator can be achieved. Experiments have been performed to demonstrate the theoretical fundamentals and the applications of the technology. Adsorbability, adsorption mechanisms, and adsorption selectivity are included in the fundamental study. The effects of particle size, magnetic reagent dosage, solid contents, magnetic matrix, applied magnetic field strengths, retention times, and feed loading capacities are included in the application studies. Three coals, including Illinois No. 6, Lower Kittanning and Pocahontas seams, have been investigated. More than 90% pyritic sulfur and ash reductions have been achieved. Technical and economic feasibilities of this technology have been demonstrated in this study. Both are competitive to that of the froth flotation approach for coal cleaning.
Date: January 1, 1992
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

Preliminary thermal/hydraulic sizing calculations for duplex tube evaporator/superheater (interchangeable units). Revision 1

Description: This is a preliminry thermal/hydraulic report reflecting work under Subtask 6.2 of Ref. 1.1. This report is an extension of the previous thermal/hydraulic design report. Parts of this report have been transmitted to GE. The detailed design basis, listed by source, is given. Additional details are discussed.
Date: June 1, 1974
Creator: Waszink, R.P.; Hwang, J.Y. & Efferding, L.E.
Partner: UNT Libraries Government Documents Department

Evaluation of exposure conditions for the water-side corrosion test of a sodium heated steam generator evaporator model employing a duplex tube (2160 hours at critical heat flux - phase III SSGM tests). [LMFBR]

Description: This report describes the specialized corrosion test water steam loop, test procedures, test conditions, and test results. A complete water chemistry and thermal hydraulic performance history is given and evaluated for the Phase III test program. The movement of the dryout location and the heat flux variations in pre- and post-critical heat flux regions are documented and analyzed. On seven occasions during the course of the test program to date, the operating conditions drifted from the CHF reference Phase III operation in the dryout regime into the DNB regime. The corresponding corrosion mechanism experienced differing exposure conditions on these occasions. CHF sensitivity to this apparent drift behavior is evaluated.
Date: December 1, 1975
Creator: Waszink, R.P.; Hwang, J.Y. & Efferding, L.E.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report No. 8, November 1, 1989--January 31, 1990

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase I study. The application of the results on coal cleaning is in progress in the Phase II study. Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals are investigated during this reporting period to determine the most effective way of using the magnetizing method for coal cleaning. The results show that the best separation performance is obtained on finely ground coals. Up to 91% ash reduction (from 22% to 3.3% ash content) at 70% coal recovery can be obtained with the magnetizing approach when Illinois No. 6 coal is processed at 90% passing 500 mesh. Even at a coarser sizes such as 90% passing 200 mesh, 86% ash reduction with 71% coal recovery can still be obtained. Although the results are probably better than using the froth flotation method, direct comparison tests will be conducted in the next reporting period.
Date: December 31, 1990
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 7, August 1--October 31, 1989

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase I study. The application of the results on coal cleaning is in progress in the Phase II study. Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals have been prepared(simulating the industrial operations) and characterized. The adsorption conditions for {minus}48 mesh ROM coals and flotation concentrates have been optimized. Magnetic separation of the reagent conditioned coals shows that both ash and pyritic sulfur can be significantly reduced. Comparing with the repeated flotation approach for coal cleaning, the magnetizing reagent enhanced magnetic separation method shows better performance on cleaning the flotation concentration at {minus}48 mesh.
Date: December 31, 1989
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 9, February 1, 1990--April 30, 1990

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase 1 study. The application of the results on coal cleaning for the Phase 2 study is completed this quarter. Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals have been investigated to determine the most effective way of using the magnetizing method for coal cleaning. The results show that the best separation performance is obtained on finely ground coals. Up to 91% ash reduction (from 22% to 3.3% ash content) and 93% pyritic sulfur reduction at 70% BTU recovery can be obtained with the magnetizing approach when Illinois No. 6 coal is processed at 90% passing 500 mesh. Even at a coarser sizes such as 90% passing 200 mesh, 86% ash reduction and 87% pyritic sulfur reduction with 74% coal TBU recovery can still be obtained. Similar results are obtained for Lower Kittanning and Pocahontas coal.
Date: December 31, 1990
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Final report

Description: The program consisted of a fundamental study to define the chemistry for the interactions between magnetic reagent and mineral and coal particles, a laboratory study to determine the applicability of this technology on coal cleaning, and a parameter study to evaluate the technical and economical feasibility of this technology for desulfurization and de-ashing under various processing schemes. Surface magnetic enhancement using magnetic reagent is a new technology developed at the Institute. This technology can be applied to separate pyrite and other minerals particles from coal with a magnetic separation after adsorbing magnetic reagent on the surface of pyrite and other minerals particles. Particles which have absorbed magnetic reagent are rendered magnetic. The adsorption can be controlled to yield selectivity. Thus, the separation of traditionally nonmagnetic materials with a magnetic separator can be achieved. Experiments have been performed to demonstrate the theoretical fundamentals and the applications of the technology. Adsorbability, adsorption mechanisms, and adsorption selectivity are included in the fundamental study. The effects of particle size, magnetic reagent dosage, solid contents, magnetic matrix, applied magnetic field strengths, retention times, and feed loading capacities are included in the application studies. Three coals, including Illinois No. 6, Lower Kittanning and Pocahontas seams, have been investigated. More than 90% pyritic sulfur and ash reductions have been achieved. Technical and economic feasibilities of this technology have been demonstrated in this study. Both are competitive to that of the froth flotation approach for coal cleaning.
Date: October 1, 1992
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 3, August 1, 1988--October 31, 1988

Description: The progress achieved during this quarter includes the reagent shelf life study, the evaluation and selection of magnetizing reagents, an experimental database for activating and depressing the adsorption of magnetizing reagents in the presence of various chemicals, an adsorption regulator investigation, the establishment of a coal surface controlling theory, and a magnetite size effect study for the separation of magnetic enhanced minerals. The work is on schedule with the original plan. Modifications include the addition of a regulator study to help proving the selectivity controlling theory. The fundamentals for applying the magnetizing reagent technology on coal cleaning are generally established during this quarter. Selective magnetic enhancement of minerals through the adsorption of magnetizing reagents has been experimentally proved. The work for the next quarter will be mainly on optimizing the selective adsorption conditions and the continuation on magnetite size effect study.
Date: December 31, 1988
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 11, August 1, 1990--October 31, 1990

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibilities of minerals have been established in Phase I study. The application of the results to study the feasibility for coal cleaning has been completed in the Phase II study. The most effective approach to clean Illinois No. 6, Ohio Lower Kittanning, and West Virginia Pocahontas coals using the magnetizing method has been determined. Phase III study is in progress during this quarter. Experimental work includes the determination of various separation parameters, including the separator and matrix selection, magnetic reagent dosage, particle size, magnetic field intensity, and retention time.
Date: December 31, 1990
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 6, May 1--July 31, 1989

Description: The fundamental chemistry for selective adsorption of magnetizing reagent on coal-associated minerals to enhance the magnetic susceptibility of minerals have been established in Phase I study. The application of the results on coal cleaning is in progress in the Phase II study. The task in Phase II study for coal selection, preparation, and characterization is completed in this reporting period. The optimization of adsorption conditions for {minus}48 mesh ROM coals and flotation concentrates is about completed. Experiments have shown that successful coal cleaning can be obtained with this magnetizing reagent approach. The task to adapt the approach to various processing schemes is just initiated.
Date: December 31, 1989
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 4, November 1, 1988--January 31, 1989

Description: The progress achieved during this quarter includes the ten months shelf life study of magnetizing reagent, the effect of cation regulators on minerals and coals, the combination effect of depressant and activator on the adsorption of magnetizing reagent, optimum magnetite size for magnetizing reagent, and the magnetic field strength for separating magnetic enhanced minerals. The work is generally on schedule with the original plan. The Phase I study (a fundamental study) is nearly completed. Selective conditions for adsorbing magnetizing reagent on minerals have been identified. The work for the next quarter will be mainly on the Phase II study. Coal will be selected, procured, characterized, and processed.
Date: December 31, 1989
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Surface magnetic enhancement for coal cleaning. Quarterly technical progress report no. 5, February 1--April 30, 1989

Description: Phase I study, which investigates the fundamental chemistry and properties of magnetizing reagents, is completed in this reporting period. Phase II study is initiated to apply the results of Phase I study for coal cleaning. Coal samples for Phase II work have been selected, ordered, and received. Processing and characterization of coal samples are in progress. Preliminary tests show that significant ash and sulfur reduction can be obtained with the magnetizing reagent method. The work is slightly behind the schedule due to the delay of coal shipment. Since the coal samples have been received, the schedule will be caught up in the next quarter. The major work for the next quarter will be the processing and characterization of coals and the optimization of magnetizing conditions for each coal.
Date: December 31, 1989
Creator: Hwang, J. Y.
Partner: UNT Libraries Government Documents Department

Verification of Steelmaking Slags Iron Content Final Technical Progress Report

Description: The steel industry in the United States generates about 30 million tons of by-products each year, including 6 million tons of desulfurization and BOF/BOP slag. The recycling of BF (blast furnace) slag has made significant progress in past years with much of the material being utilized as construction aggregate and in cementitious applications. However, the recycling of desulfurization and BOF/BOP slags still faces many technical, economic, and environmental challenges. Previous efforts have focused on in-plant recycling of the by-products, achieving only limited success. As a result, large amounts of by-products of various qualities have been stockpiled at steel mills or disposed into landfills. After more than 50 years of stockpiling and landfilling, available mill site space has diminished and environmental constraints have increased. The prospect of conventionally landfilling of the material is a high cost option, a waste of true national resources, and an eternal material liability issue. The research effort has demonstrated that major inroads have been made in establishing the viability of recycling and reuse of the steelmaking slags. The research identified key components in the slags, developed technologies to separate the iron units and produce marketable products from the separation processes. Three products are generated from the technology developed in this research, including a high grade iron product containing about 90%Fe, a medium grade iron product containing about 60% Fe, and a low grade iron product containing less than 10% Fe. The high grade iron product contains primarily metallic iron and can be marketed as a replacement of pig iron or DRI (Direct Reduced Iron) for steel mills. The medium grade iron product contains both iron oxide and metallic iron and can be utilized as a substitute for the iron ore in the blast furnace. The low grade iron product is rich in calcium, magnesium and iron ...
Date: October 4, 2006
Creator: Hwang, J.Y.
Partner: UNT Libraries Government Documents Department

UTILIZATION OF LOW NOx COAL COMBUSTION BY-PRODUCTS

Description: Plastic fillers and powder-based aluminum composites typically use fly ash with a particle size of less than five microns. Clean ash classification generates a fine fraction, {approximately}5 microns, and a coarse fraction, {approximately}30 microns. There is a need to find additional uses for the coarser size fraction. Concrete is one area being studied in this project. Other possible applications in which a 30-micron ceramic particle with good flowability is desired include ceramic slurries for investment casting, ceramic coatings for metal casting sand molds, and for use as a surfacing sand. If more information is obtained about these or other applications, it may be included in these reports.
Date: August 1, 1998
Creator: HEIN, A.M.; HWANG, J.Y. & HUANG, X.
Partner: UNT Libraries Government Documents Department

Final Report: Metal Perhydrides for Hydrogen Storage

Description: Hydrogen is a promising energy source for the future economy due to its environmental friendliness. One of the important obstacles for the utilization of hydrogen as a fuel source for applications such as fuel cells is the storage of hydrogen. In the infrastructure of the expected hydrogen economy, hydrogen storage is one of the key enabling technologies. Although hydrogen possesses the highest gravimetric energy content (142 KJ/g) of all fuels, its volumetric energy density (8 MJ/L) is very low. It is desired to increase the volumetric energy density of hydrogen in a system to satisfy various applications. Research on hydrogen storage has been pursed for many years. Various storage technologies, including liquefaction, compression, metal hydride, chemical hydride, and adsorption, have been examined. Liquefaction and high pressure compression are not desired due to concerns related to complicated devices, high energy cost and safety. Metal hydrides and chemical hydrides have high gravimetric and volumetric energy densities but encounter issues because high temperature is required for the release of hydrogen, due to the strong bonding of hydrogen in the compounds. Reversibility of hydrogen loading and unloading is another concern. Adsorption of hydrogen on high surface area sorbents such as activated carbon and organic metal frameworks does not have the reversibility problem. But on the other hand, the weak force (primarily the van der Waals force) between hydrogen and the sorbent yields a very small amount of adsorption capacity at ambient temperature. Significant storage capacity can only be achieved at low temperatures such as 77K. The use of liquid nitrogen in a hydrogen storage system is not practical. Perhydrides are proposed as novel hydrogen storage materials that may overcome barriers slowing advances to a hydrogen fuel economy. In conventional hydrides, e.g. metal hydrides, the number of hydrogen atoms equals the total valence of the ...
Date: July 26, 2011
Creator: Hwang, J-Y.; Shi, S.; Hackney, S.; Swenson, D. & Hu, Y.
Partner: UNT Libraries Government Documents Department