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A Kinetic Model for Conventional Flotation of Coal

Description: The U.S. Bureau of Mines has developed a computer model to 'describe a flotation process. Coal data from conventional flotation has been converted to a simple, two-parameter kinetic model developed by Reuter and van Deventer (j,2 3. Each set of coal data was represented by two constants, a and a, and an average flotation rate. The success of the model was demonstrated when the calculated and experimental recoveries showed good correlation. The two-parameter model allows complex data to be defined much more efficiently than traditional knowledge-based models.
Date: 1995
Creator: Susko, Frank J. & Stanley, Don A.
Partner: UNT Libraries Government Documents Department

Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 6, April 1, 1995--June 30, 1995

Description: The major activities of the period were production operations of the demonstration circuit at Drummond`s Chetopa Preparation Plant near Graysville, Alabama. As the shakedown runs had shown, excellent quality Mulled Coal could be produced, and a total of 870 tonnes (966 tons) was produced. Quality was consistently better than the acceptable level. Immediately following the completion of the production demonstration, removal of equipment and decommissioning of the demonstration facility was undertaken and completed.
Date: August 22, 1996
Partner: UNT Libraries Government Documents Department

Preparation Characteristics of Illinois Coals

Description: Report issued by the Bureau of Mines discussing the mechanical coal-preparation characteristics. As stated in the introduction, "this second publication reports the washability and screen analyses of the important Illinois coal beds, showing the quality of product that would result when the raw coal is subjected to preparatory treatment" (p. 1). This report includes tables, maps, and illustrations.
Date: 1949
Creator: Crentz, William L. & Fraser, Thomas
Partner: UNT Libraries Government Documents Department

Novel Supported Bimetallic Carbide Catalysts for Coprocessing of Coal with Waste Materials

Description: The effect of phosphorus on Mo<sub>2</sub>C supported on {gamma}-Al<sub>2</sub>O<sub>3</sub> and activated carbon was studied. The catalysts were characterized by CO chemisorption, BET surface area measurements, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and tested for their reactivity for hydroprocessing reactions, particularly hydrogenation (HYD), hydrodesulfurization (HDS) and hydrodenitrogenation (HDN), using model liquid compounds. The P-containing catalysts had higher reactivity for HDN than those without P. HDS was higher when the Mo<sub>2</sub> C was synthesized on {gamma}-Al<sub>2</sub> O<sub>3</sub> previously treated with P than when the Mo component and P were added together on {gamma}-Al<sub>2</sub>O<sub>3</sub>. Post reaction characterization indicates that the catalysts were tolerant of sulfur.
Date: March 30, 1998
Creator: Song, C.; Cox, D. F.; Allen, F. & Oyama, S. T.
Partner: UNT Libraries Government Documents Department

Engineering development of advanced physical fine coal cleaning for premium fuel applications. Quarterly technical progress report 11, April--June, 1995

Description: The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by design, and construction of a 2-t/hr process development unit (PDU). The PDU will then be operated to generate 200 tons of each of three project coals, by each process. During Quarter 11 (April--June, 1995), work continued on the Subtask 3.2 in-plant testing of the Microcel{trademark} flotation column at the Lady Dunn Preparation Plant with the installation and calibration of a refurbished 30-inch diameter column. The evaluation of toxic trace element data for column flotation samples continued, with preliminary analysis indicating that reasonably good mass balances were achieved for most elements, and that significant reductions in the concentration of many elements were observed from raw coal, to flotation feed, to flotation product samples. Significant progress was made on Subtask 6.5 selective agglomeration bench-scale testing. Data from this work indicates that project ash specifications can be met for all coals evaluated, and that the bulk of the bridging liquid (heptane) can be removed from the product for recycle to the process. The detailed design of the 2 t/hr selective agglomeration module progressed this quarter with the completion of several revisions of both the process flow, and the process piping and instrument diagrams. Procurement of coal for PDU operation began with the purchase of 800 tons of Taggart coal. Construction of the 2 t/hr PDU continued through this reporting quarter and is currently approximately 60% complete.
Date: July 31, 1995
Creator: Moro, N.; Shields, G.L.; Smit, F.J. & Jha, M.C.
Partner: UNT Libraries Government Documents Department

Engineering development of advanced physical fine coal cleaning for premium fuel applications. Quarterly technical progress report 13, October--December, 1995

Description: The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by the design, construction, and operation of a 2-t/hr process development unit. During Quarter 13 (October--December 1995), testing of the GranuFlow dewatering process indicated a 3--4% reduction in cake moisture for screen-bowl and solid-bowl centrifuge products. The Orimulsion additions were also found to reduce the potential dustiness of the fine coal, as well as improve solids recovery in the screen-bowl centrifuge. Based on these results, Lady Dunn management now plans to use a screen bowl centrifuge to dewater their Microcel{trademark} column froth product. Subtask 3.3 testing, investigating a novel Hydrophobic Dewatering process (HD), continued this quarter. Continuing Subtask 6.4 work, investigating coal-water-slurry formulation, indicated that selective agglomeration products can be formulated into slurries with lower viscosities than advanced flotation products. Subtask 6.5 agglomeration bench-scale testing results indicate that a very fine grind is required to meet the 2 lb ash/MBtu product specification for the Winifrede coal, while the Hiawatha coal requires a grind in the 100- to 150-mesh topsize range. Detailed design work remaining involves the preparation and issuing of the final task report. Utilizing this detailed design, a construction bid package was prepared and submitted to three Colorado based contractors for quotes as part of Task 9.
Date: January 31, 1996
Creator: Moro, N.; Shields, G.L.; Smit, F.J. & Jha, M.C.
Partner: UNT Libraries Government Documents Department

Evaluation of hyperbaric filtration for fine coal dewatering. Eleventh quarterly technical progress report, April 1, 1995--June 30, 1995

Description: The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. The program consist of three phases, namely Phase I - Model Development, Phase II - Laboratory Studies, Phase III - Field Testing. The Pennsylvania State University is leading efforts in Phase I, the University of Kentucky in Phase II, and Consol Inc. in Phase III of the program. All three organizations are involved in all the three phases of the program. The Pennsylvania State University is developing a theoretical model for hyperbaric filtration systems, whereas the University of Kentucky is conducting experimental studies to investigate fundamental aspects of particle-liquid interaction and application of high pressure filter in fine coal dewatering. The optimum filtration conditions identified in Phase I and II will be tested in a Consol Inc. coal preparation plant using an Andritz Ruthner portable hyperbaric filtration unit.
Date: December 1, 1995
Creator: Parekh, B.K.; Hogg, R. & Fonseca, A.
Partner: UNT Libraries Government Documents Department

A modified release analysis procedure using advanced froth flotation mechanisms. Final technical report, September 1, 1995--August 31, 1996

Description: Recent studies indicate that the optimum separation performances achieved by multiple stage cleaning using various column flotation technologies and single stage cleaning using a Packed-Flotation Column are superior to the performance achieved by the traditional release procedure, especially in terms of pyritic sulfur rejection. This superior performance is believed to be the result of the advanced flotation mechanisms provided by column flotation technologies. Thus, the objective of this study was to develop a suitable process utilizing the advanced froth flotation mechanisms to characterize the true flotation response of a coal sample. This investigation resulted in the development of a modified coal flotation characterization procedure, termed as the Advanced Flotation Washability (AFW) technique. The apparatus used for this procedure is a batch operated Packed-Column device which provides enhanced selectivity due to a plug-flow environment and a deep froth zone. The separation performance achieved by the AFW procedure was found to be superior to those produced by the conventional tree and release procedures for three nominally -100 mesh coal samples and two micronized samples. The largest difference in separation performance was obtained on the basis of product pyritic sulfur content. A comparison conducted between the AFW and the release procedures at an 80% recovery value showed that the AFW technique provided a 19% improvement in the reduction of pyritic sulfur. For an Illinois No. 5 coal sample, this improvement corresponded to a reduction in pyritic sulfur content from 1.38% to 0.70% or a total rejection of 66%. Micronization of the sample improved the pyritic sulfur rejection to 85% while rejecting 92% of the ash-bearing material. In addition, the separation performance provided by the AFW procedure was superior to that obtained from multiple cleaning stages using a continuous Packed-Column under both kinetic and carrying-capacity limiting conditions.
Date: May 1, 1997
Creator: Honaker, R.Q. & Mohanty, M.K.
Partner: UNT Libraries Government Documents Department

Improvement of storage, handling, and transportability of fine coal. Final report

Description: The Mulled Coal process is a technology which has evolved from a line of investigations which began in the 1970`s. There was a major breakthrough in 1990, and since then, with significant support from DOE-PETC, the technology has progressed from the conceptual stage to a proven laboratory process. It is a simple process which involves the addition of a low cost specifically formulated reagent to wet fine coal by mixing the two in a pug mill. Although the converted material (Mulled Coal) retains some of its original surface moisture, it handles, transports, and stores like dry coal. But, unlike thermally dried fine coal Mulled Coal is not dusty, it will not rewet, and it causes no fugitive dust problems. This project was designed to advance the technology from the status of a process which works well in the laboratory to the status of a technology which is fully ready for commercialization. Project objectives were to: 1. Prove the concept that the technology can be used to produce Mulled Coal of a consistent quality, on a continuous basis, at a convincing rate of production, and at a major preparation plant which produces fine clean coal on a commercial basis. 2. Prove the concept that Mulled Coal, either as a blend with coarser clean coal or as a stand-alone fuel will successfully pass through a representative cross section of conventional coal storage, handling and transportation environments without causing any of the problems normally associated with wet fine coal. 3 Test the design and reliability of Mulled Coal circuit equipment and controls. 4. Test the circuit over a wide range of operating conditions. 5. Project scale-up designs for major equipment components and control circuits. 6. Forecast capital and operating costs for commercial circuits ranging from 25 TPH to 75 TPH. This report describes ...
Date: March 1, 1996
Creator: Maxwell, R.C. Jr. & Jamison, P.R.
Partner: UNT Libraries Government Documents Department

POC-SCALE TESTING OF OIL AGGLOMERATION TECHNIQUES AND EQUIPMENT FOR FINE COAL PROCESSING

Description: This report covers the technical progress achieved from July 01, 1997 to September 30, 1997 on the POC-Scale Testing Agglomeration Techniques and Equipment for Fine Coal Processing project. Experimental procedures and test data for recovery of fine coal from coal fines streams generated at a commercial coal preparation plant are described. Two coal fines streams, namely Sieve Bend Effluent and Cyclone Overflow were investigated. The test results showed that ash was reduced by more than 50% at combustible matter recovery levels exceeding 95%.
Date: January 1, 1998
Partner: UNT Libraries Government Documents Department

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, July 1, 1995--September 30, 1995

Description: The development of practical technologies for the deep cleaning of coal has been seriously hampered by the problems of carrying out efficient coal/mineral separations at the very fine sizes (often finer than 10 mm) needed to achieve adequate liberation of the mineral matter from the coal matrix. It is generally recognized that surface-based separation processes such as froth flotation or selective agglomeration offer considerable potential for such applications but there remain many problems in obtaining the required selectivity with acceptable recovery of combustible matter. In froth flotation, selectivity is substantially reduced at fine sizes due, primarily, to overloading of the froth phase which leads to excessive carryover of water and entrained mineral matter. Oil agglomeration, on the other hand, can provide good selectivity at low levels of oil addition but the agglomerates tend to be too fragile for separation by the screening methods normally used. The addition of larger amounts of oil can yield large, strong agglomerates which are easily separated but the selectivity is reduced and reagent costs can become excessive.
Date: July 1, 1995
Creator: Chander, S. & Hogg, R.
Partner: UNT Libraries Government Documents Department

Development of a coal quality expert. Technical progress report No. 17, April 1994--June 1994

Description: The work falls under DOE`s Clean Coal Technology Program category of `Advanced Coal Cleaning.` The 51-month project will provide the utility industry with a PC software program to evaluate the potential for coal cleaning, blending, and switching options to reduce emissions while producing electricity.
Date: October 5, 1994
Partner: UNT Libraries Government Documents Department

Engineering development of advanced physical fine coal cleaning for premium fuel applications. Quarterly technical progress report 15, April--June 1996

Description: Goal is engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. Scope includes laboratory research and bench-scale testing on 6 coals to optimize these processes, followed by design/construction/operation of a 2-t/hr PDU. During this quarter, parametric testing of the 30-in. Microcel{trademark} flotation column at the Lady Dunn plant was completed and clean coal samples submitted for briquetting. A study of a novel hydrophobic dewatering process continued at Virginia Tech. Benefits of slurry PSD (particle size distribution) modification and pH adjustment were evaluated for the Taggart and Hiawatha coals; they were found to be small. Agglomeration bench-scale test results were positive, meeting product ash specifications. PDU Flotation Module operations continued; work was performed with Taggart coal to determine scaleup similitude between the 12-in. and 6-ft Microcel{trademark} columns. Construction of the PDU selective agglomeration module continued.
Date: July 25, 1996
Creator: Moro, N.; Shields, G.L.; Smit, F.J. & Jha, M.C.
Partner: UNT Libraries Government Documents Department

Pulverization induced charge: In-line dry coal cleaning. Technical progress report No. 4, April 1, 1995--June 30, 1995

Description: Research on coal cleaning continued. An electrostatic coal separation probe was designed and constructed for on-site power plant tests. This probe was used to validate the charge measurement work and provide a rapid indicator of the pulverized coal separability. Laboratory test were conducted on coal samples to evaluate separation under ideal conditions. The results indicated that improvement in in-situ separation may be attained by either separator design changes or particle charge improvements.
Date: January 1, 1996
Partner: UNT Libraries Government Documents Department

A study of multistage/multifunction column for fine particle separation. Quarterly technical progress report, January 1, 1996-- March 31, 1996

Description: The overall objective of the proposed research program is to explore the potential application of a new invention involving a multistage column equipped with vortex-inducing loop-flow contactors (hereafter referred to as the multistage column) for fine coal cleaning process. The research work will identify the design parameters and their effects on the performance of the separation process. The results of this study will provide an engineering basis for further development of this technology in coal cleaning and in the general areas of fluid/particle separation. In the last quarter, we investigated the mixing and loop flow (circulation) behaviors around the contactors. In this quarter, the fine coal beneficiation tests were carried out in the multistage column and conventional column.
Date: April 20, 1996
Creator: Chiang, Shiao-Hung
Partner: UNT Libraries Government Documents Department

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, October 1--December 30, 1995

Description: Goals are to demonstrate the technical and economic feasibility of a micro-agglomerate flotation process (combination of oil-agglomeration and froth flotation) and to establish the essential criteria for reagent selection and system design and operation. The research program was organized into the following tasks: interfacial studies, emulsification, agglomerate growth and structure, and agglomerate flotation. Work on the first two tasks has been completed.
Date: April 1, 1996
Creator: Chandler, S. & Hogg, R.
Partner: UNT Libraries Government Documents Department

A study of Multistage/Multifunction Column for Fine Coal Cleaning CRADA PC93-005, Final Report

Description: The overall objective of the this research project is to explore the potential applicability of a multistage column for fine coal cleaning and other applications in fluid particle separation. The research work identifies the design parameters and their effects on the performance of the separation device. The results of this study provide an engineering data basis for further development of this technology in coal cleaning and in general areas of fluid and particle separations.
Date: September 4, 1998
Creator: Lai, Ralph; Chiang, Shiao-Hung; He, Daxin & Feng, Yuru
Partner: UNT Libraries Government Documents Department

Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 4, October 1, 1994--December 31, 1994

Description: The objectives of this project are to demonstrate that: The Mulled Coal process, which has been proven to work on a wide range of wet fine coals at bench scale, will work equally well on a continuous basis, producing consistent quality at a convincing rate of production in a commercial coal preparation plant. The wet product from a fine coal cleaning circuit can be converted to a solid fuel form for ease of handling and cost savings in storage and rail car transportation. A wet fine coal product thus converted to a solid fuel form, can be stored, shipped, and burned with conventional fuel handling, transportation, and combustion systems. During this fourth quarter of the contract period, activities were underway under Tasks 2 and 3. Sufficient characterization of the bench-scale testing and pilot-plant testing results enabled the design and procurement activities to move forward. On that basis, activities in the areas of design and procurement that had been initiated during the previous quarter were conducted and completed.
Date: August 20, 1996
Partner: UNT Libraries Government Documents Department

Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 5, January 1, 1995--March 31, 1995

Description: The Mulled Coal process was developed as a means of overcoming the adverse handling characteristics of wet fine coal without thermal drying. The process involves the addition of a low cost, harmless reagent to wet fine coal using off-the-shelf mixing equipment. Based on laboratory- and bench-scale testing, Mulled Coal can be stored, shipped, and burned without causing any of the plugging, pasting, carryback and freezing problems normally associated with wet coal. The objectives of this project are to demonstrate that: the Mulled Coal process, which has been proven to work on a wide range of wet fine coals at bench scale, will work equally well on a continuous basis, producing consistent quality at a convincing rate of production in a commercial coal preparation plant; the wet product from a fine coal cleaning circuit can be converted to a solid fuel form for ease of handling and cost savings in storage and rail car transportation; and a wet fine coal product thus converted to a solid fuel form, can be stored, shipped, and burned with conventional fuel handling, transportation, and combustion systems. During this reporting period, virtually all of the technical activities and progress was made in the areas of circuit installation and startup operations. Work in these activity areas are described.
Date: August 21, 1996
Partner: UNT Libraries Government Documents Department

Fine coal fractionation using a magnetohydrostatic separation process CRADA 91-003. Final report

Description: The magnetohydrostatic separation (MHS) process uses a magnetic fluid which has the ability to float a submerged particle in a magnetic field. The objective of this project was to develop a technique for laboratory gravity fractionation of coal using MHS.
Date: October 31, 1992
Creator: Cho, Heechan & Killmeyer, R.P.
Partner: UNT Libraries Government Documents Department

Development of an on-line coal washability analyzer. Semi-annual technical report, September 1, 1996--March 31, 1997

Description: Washability analysis is the basis for nearly all coal preparation plant separations. Unfortunately, there are no on-line techniques for determining this most fundamental of all coal cleaning information. In light of recent successes at the University of Utah, it now appears possible to determine coal washability on-line through the use of x-ray computed tomography (CT) analysis. The successful development of such a device is critical to the establishment of process control and automated coal blending systems. In this regard, Virginia Tech, Terra Tek Inc., and Cyprus-Amax Coal Company have joined with the University of Utah and agreed to undertake the development of an x-ray CT-based on-line coal washability analyzer with financial assistance from DOE. The three-year project will cost $594,571, of which 33% ($194,575) will be cost-shared by the participants. The project will involve development of appropriate software and extensive testing/evaluation of well- characterized coal samples from three coal preparation plants. Each project participant brings special expertise to the project which is expected to create a new dimension in coal cleaning technology. Finally, it should be noted that the analyzer may prove to be a universal analyzer capable of providing not only washability analysis, but also particle size distribution analysis, ash analysis and perhaps pyritic sulfur analysis.
Date: March 31, 1997
Creator: Miller, J.D.; Lin, C.L.; Luttrell, G.H.; Adel, G.T.; Owen, L.B. & Fish, L.
Partner: UNT Libraries Government Documents Department

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, October 1, 1994--December 31, 1994

Description: The development of practical technologies for the deep cleaning of coal has been seriously hampered by the problems of carrying out efficient coal/mineral separations at the very fine sizes (often finer than 10 mm) needed to achieve adequate liberation of the mineral matter from the coal matrix. It is generally recognized that surface-based separation processes such as froth flotation or selective agglomeration offer considerable potential for such applications but there remain many problems in obtaining the required selectivity with acceptable recovery of combustible matter. In froth flotation, selectivity is substantially reduced at fine sizes due, primarily, to overloading of the froth phase which leads to excessive carryover of water and entrained mineral matter. Oil agglomeration, on the other hand, can provide good selectivity at low levels of oil addition but the agglomerates tend to be too fragile for separation by the screening methods normally used. The addition of larger amounts of oil can yield large, strong agglomerates which are easily separated but the selectivity is reduced and reagent costs can become excessive. We are investigating the use of a hybrid process - micro-agglomerate flotation - which is a combination of oil-agglomeration and froth flotation. The basic concept is to use small quantities of oil to promote the formation of dense micro-agglomerates with minimal entrapment of water and mineral particles, and to use froth flotation to extract these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units are agglomerates (about 30-50 mm in size) rather than individual coal particles (1-10 mm) the problems of froth overload and water/mineral carryover should be significantly alleviated. Micro-agglomerate flotation has considerable potential for the practical deep cleaning of coal on a commercial scale.
Date: January 1, 1995
Creator: Chander, S. & Hogg, R.
Partner: UNT Libraries Government Documents Department

POC-scale testing of a dry triboelectrostatic separator for fine coal cleaning

Description: The Proof-of-Concept (POC) triboelectrostatic separator (TES) has now been successfully installed at the Virginia Tech pilot-plant. As a result, most of the personnel assigned to this project during the past quarter have been performing work elements associated with the installation and shakedown testing of the electrostatic separator, tribocharger system, product conveying systems and nitrogen purge system (Tasks 4, 5.1 and 5.2). A representative from Carpco also carried out training in the operating features of the unit during the past month. Most of the shakedown test work has now been successfully completed. However, several minor operational problems associated with the pilot-scale equipment are currently in the process of being resolved.
Date: July 1, 1999
Creator: Yoon, R.-H.; Luttrell, G.H.; Adel, G.T. & Walters, A.D.
Partner: UNT Libraries Government Documents Department