DoE EPA U.S. Department of Energy Division of Fossil Fuel Extraction PMTC-5(79) Pittsburgh Mining Technology Center Pittsburgh. PA 15213 US. Environmental Protection Agency Industrial Environmental Research Laboratory Research Triangle Park NC 27711 EPA-600/7-79-149 June 1979 Washability Characteristics of Arkansas and Texas Lignites: Report of Investigations Interagency Energy/Environment R&D Program Report ------- RESEARCH REPORTING SERIES Research reports of the Office of Research and Development, U.S. Environmental Protection Agency, have been grouped into nine series. These nine broad cate- gories were established to facilitate further development and application of en- vironmental technology. Elimination of traditional grouping was consciously planned to foster technology transfer and a maximum interface in related fields. The nine series are: 1. Environmental Health Effects Research 2. Environmental Protection Technology 3. Ecological Research 4. Environmental Monitoring 5. Socioeconomic Environmental Studies 6. Scientific and Technical Assessment Reports (STAR) 7. Interagency Energy-Environment Research and Development 8. "Special" Reports 9. Miscellaneous Reports This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT RESEARCH AND DEVELOPMENT series. Reports in this series result from the effort funded under the 17-agency Federal Energy/Environment Research and Development Program. These studies relate to EPA's mission to protect the public health and welfare from adverse effects of pollutants associated with energy sys- tems. The goal of the Program is to assure the rapid development of domestic energy supplies in an environmentally-compatible manner by providing the nec- essary environmental data and control technology Investigations include analy- ses of the transport of energy-related pollutants and their health and ecological effects; assessments of, and development of, control technologies for energy systems; and integrated assessments of a wide range of energy-related environ- mental issues. EPA REVIEW NOTICE This report has been reviewed by the participating Federal Agencies, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Government, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. This document is available to the public through the National Technical Informa- tion Service, Springfield, Virginia 22161. Price: Paper Copy $7.00 Microfiche $3.50 ------- EPA-600/7-79-149 June 1979 PMTC-5(79) Distribution Category UC-90b Washability Characteristics of Arkansas and Texas Lignites: Report of Investigations by J. A. Cavallaro and A. F. Baker U. S. Department of Engergy Coal Preparation Division Pittsburgh Mining Technology Center 4800 Forbes Avenue Pittsburgh, PA 15213 EPA Interagency Agreement No. DXE685-AK Program Element No. EHE623A EPA Project Officer: David A. Kirchgessner Industrial Environmental Research Laboratory Office of Energy, Minerals, and Industry Research Triangle Park, NC 27711 Prepared for U.S. ENVIRONMENTAL PROTECTION AGENCY U.S. Department of Energy Office of Research and Development and Division of Fossil Fuel Extraction Washington, DC 20460 Pittsburgh Mining Technology Center Pittsburgh, PA 15213 ------- CONTENTS Page Abstract 1 Introduction 1 Acknowledgments 3 Test procedure 3 Collection of samples 3 Sample preparation 4 Arkansas lignites 7 Geology 7 Reserves • 7 Production 10 Texas lignites 10 Geology , 10 Resources 11 Production • 11 Experimental results 15 Arkansas lignite 15 Texas lignite 24 Sodium reduction 44 Discussion of results 44 Conclusions 46 References 47 ii ------- ILLUSTRATIONS Fig. Page 1. Flow diagram showing preparation of face samples 5 2. Areas of shallow lignite deposits in Arkansas 8 3. Generalized cross section 9 4. Distribution of Texas near-surface lignite 12 TABLES 1. Identification of coal samples collected 3 2. Estimated original reserves of Arkansas lignite in deposits more than 30 inches thick and lying beneath less than 100 feet of overburden 10 3. Stratigraphic occurrence of Texas lignite 13 4. Near-surface potential Texas lignite resources 14 5. Chemical and physical analyses of raw coal channel samples . 16 6. Detailed washability analyses of sample No. 1 1? 7. Detailed washability analyses of sample No. 2 20 8. Detailed washability analyses of sample No. 3 22 9. Detailed washability analyses of sample No. 4 25 10. Detailed washability analyses of sample No. 5 27 11. Detailed washability analyses of sample No. 6 30 12. Detailed washability analyses of sample No. 7 32 13. Detailed washability analyses of sample No. 8 35 14. Detailed washability analyses of sample No. 9 37 iii ------- Page 15. Detailed washability analyses of sample No. 10 40 16. Detailed washability analyses of sample No. 11 42 17. Ion exchange test results with minus 14 mesh Arkansas and Texas lignites 45 iv ------- WASHABILITY CHARACTERISTICS OF ARKANSAS AND TEXAS LIGNITES by J. A. Cavallaro1 and A. F. Baker2 ABSTRACT This report describes the washability characteristics of eleven channel samples of lignite, four from Arkansas and seven from Texas. Only two of the samples, those collected from Dallas County, Ar- kansas, could be upgraded to meet the current EPA new source perform- ance standard (NSPS) of 1.2 pounds S02/MM Btu. The other nine samples, although averaging only a little over 1 percent total sulfur, were relatively high in organic sulfur considering their low Btu/lb value, and could not be upgraded to meet the standard. Physical coal cleaning of these samples, however, provided signifi- cant ash reduction which may reduce boiler fouling. It was demonstrated that much of the sodium can be removed from these Arkansas and Texas lignites by ion exchange. Analyses showed 37 to 91 percent sodium oxide reduction after treatment with a solution containing calcium ions. INTRODUCTION In 1977 the electric utilities burned 477 million tons of coal with an average sulfur content of 2.0 percent. The amount of coal consumed by electric utilities is anticipated to reach 525 million tons by 1980 and approximately a billion tons by the year 2000 (_7). Because coal- fired electric utility plants are the major source of sulfur oxide air pollution in the United States today, EPA and its counterparts have placed major emphasis on developing methods for controlling these emissions. Since 1965, the Environmental Protection Agency (or its predecessor The National Air Pollution Control Administration) has funded a study by 1Supervisory Chemical Engineer. Supervisory Physicist. ------- the Coal Preparation Division of the U.S. Department of Energy (DOE), formerly the U.S. Bureau of Mines, Department of the Interior, to deter- mine the amount of the various forms of sulfur in major sources of utility steam coals and the washabilities of these coals. The EPA new source performance standard is 1.2 pounds S02/MM Btu. This means that a coal containing 13,000 Btu/lb can contain only 0.8 percent sulfur in order to meet the standard. However, a lignite averaging 10,000 Btu/lb (moisture free) could only contain 0.6 percent sulfur in order to meet the standard. Because of our need for increasing coal utilization to meet rapidly growing energy needs, the DOE is expanding its investigation of the preparation characteristics of United States coals to include various low rank coals and lignite. To date, very little information has been published on the removal of impurities from lignite by coal preparation. The purpose of the present study was to determine the potential of upgrading selected Arkansas and Texas lignites by coal preparation techniques to improve their utilization in combustion and conversion processes. Physical cleaning can reduce the sulfur in coal which occurs as pyrite, but it leaves the organic sulfur in the clean coal. For some coals, however, coal cleaning may eliminate or minimize the need for stack-gas scrubbing for achieving air quality criteria. Hence, coal washing techniques that remove pyritic sulfur and other impurities cheaply and efficiently can be used as a primary upgrading step before utilization. The deposition of ash on the heat transfer surfaces in boilers is a problem in lignite combustion. This problem is aggravated by the mineral constituents present in lignite. Sodium, an alkaline metal, has been found to be the element chiefly responsible for accelerating the fouling of boiler tubes (12). At high sodium levels, frequent cleaning of the boilers is often necessary to maintain steam production. Tests have shown, however, that the sodium content of lignite can be reduced by an ion exchange process (_8). It has also been found that the rate of boiler fouling depends upon the quantity of ash present in lignite. Tufte et al. (12) have shown that the ash fouling rate of boiler tubes increases exponentially with the ash content regardless of the sodium oxide content of the ash. This report describes the results from washability tests to deter- mine the ash and sulfur reduction potential of selected Arkansas and Texas lignites by stage crushing and subsequent specific gravity sepa- ration. Supplementary data are presented to show the effect of treating these lignites by an ion exchange process to reduce their sodium con- tent. Data are also presented to characterize the chemical and physical properties of the lignite samples collected in this investigation. ------- ACKNOWLEDGMENTS The authors wish to acknowledge the cooperation and help of those engineers, geologists, and mining company officials contacted during this investigation. The assistance of R. B. Stroud, U.S. Bureau of Mines State Liaison Officer, Arkansas, and M. E. Hawkins, U.S. Bureau of Mines State Liaison Officer, Texas, is gratefully acknowledged. The authors also wish to thank R. A. Welsh, U.S. Department of Energy for collecting the samples and W. Dickie, C. Grimes, and U. Weinheimer, U.S. Department of Energy, for performing the washability analyses on the various coal samples. The work was funded by the Environmental Protection Agency, and the authors wish to acknowledge the assistance of T. Kelly Janes, James Kilgroe, and David A. Kirchgessner from the Industrial Environmental Research Laboratory of the Environmental Protection Agency, Research Triangle Park, N.C. TEST PROCEDURE Collection of Samples Face samples were collected from surface mines in Arkansas (four samples) and Texas (seven samples). The mines which were active were producing coal primarily for consumption by electric utilities. The four channel samples from Arkansas ranged from 2 feet 7 inches to 3 feet 1 inch thick; the seven samples from Texas ranged from 5 feet 4 inches to 12 feet thick. Four of the Texas mines sampled produce coal for electric power generation, one produces coal for making activated carbon, and two are prospect mines. Identification of the coal samples col- lected is presented in table 1. TABLE 1. - Identification of coal samples collected Sample No. 1 2 3 4 5 6 7 8 9 10 11 State Arkansas ii 11 11 .Texas It " " " n " County Dallas ii Ouachita Saline Freestone it Harrison Milam Panola Titus Angelina Group Wilcox (top bench) Wilcox (bottom bench) " ii " it n it " " Claiborne ------- Face samples were collected according to the procedure recommended by Fleldner and Selvig (2) and Holmes (5), except that the dimensions of each sample cut were expanded to permit 600 pounds of coal to be taken from the face. Partings and impurities were not removed from the samples unless otherwise noted. The face was cleared of loose coal or dirt for a width of approximately 5 feet. Loose pieces of roof were also taken down to prevent them from falling into the sample while it was being collected. Within the cleaned area of the face, the coal was cut from the roof to the floor in a channel 1 inch deep and about 3 feet wide to remove any altered or otherwise inferior coal such as oxidized coal. The floor was then cleared and smoothed, and a sampling cloth was spread to catch the sample. The channel sample was cut perpendicular to the lay of the coalbed, approximately 10 inches deep, and wide enough to provide a sample of 600 pounds. For example, for a 4-foot-thick coalbed a channel 30.5 inches wide would be collected. The procedure is modified when a strip mine sample is obtained where the overburden has been removed. In this case, the depth and width of the channel would be equal. For example, for the 4-foot-thick bed noted above, the channel would be 17.5 inches deep by 17.5 inches wide. The collected sample includes all partings and other impurities occurring in the channel. Sample Preparation The 600-pound channel samples collected in the field were loaded into steel drums containing plastic liners and returned to the coal preparation laboratory for processing. The sample preparation procedure is outlined in the flowsheet shown in figure 1. Each sample to be tested was air dried and crushed to 1-1/2-inch top size using a roll crusher. The sample was then coned, long piled, and shoveled into four pans, according to ASTM specifications, and divided into two portions by combining opposite pans. Each sample was divided into two coarse por- tions. One portion was crushed to 1-1/2 inches top size and sized 1-1/2 inches by 3/8 inch, 3/8 inch by 14 mesh, 14 by 100 mesh, and minus 100 mesh. The other portion was crushed to 3/8 inch top size and sized 3/8 inch by 14 mesh, 14 by 100 mesh, and minus 100 mesh. The cumulative percentage of material retained on each screen was plotted on Rosin and Rammler paper (9), and the size distribution coefficient n was deter- mined from the slope of the line representing the data. The size dis- tribution constant n is a measure of the degree of dispersion of par- ticle size. The percentage of fines in a coal tend to increase with decreasing values of n. The minus 100 mesh material was removed from each portion and analyzed for chemical and physical properties. Each of the remaining portions was float-sink tested at 1.30, 1.40, and 1.60 specific gravities using CERTIGRAV,3 a commercial organic ^Reference to specific brands does not imply endorsement by the Depart- ment of Energy. ------- Gross sample crushed to 2 - inch top size Screened Long piled and divided \/ |inch x 14 meshx 14x100 mesh Float- sink tested 12 inches x 0 crushed to |-inch top size Riffled •| inch x 0 crushed to 14 -mesh top size Screened Riffled , Y//'XX7///'/// SS. . ^ I inch it. 14 mesh / O-QT sss ss s s s s / / s s Ss/s 14 x 100 mesh//A /S/S/S, // / / Ss/s/ ////'////// /// / / / /A 14 mesh x Q //S S S / / / S / / S j> 14 mesh x 0 raw cool head sample FIGURE 1. - Flow diagram showing preparation of face samples. 1-22-77 L-15702 ------- liquid of standardized specific gravity produced by American Minechem Corporation; the solution tolerance was ±0.001 specific gravity unit and was monitored using a spindle hydrometer. A third portion crushed to 14 mesh top size was float-sink tested in its entirety at the same specific gravities. Analyses of sodium oxide in the ash were obtained on each of the specific gravity fractions of the sample crushed to 14 mesh top size. However, the sodium oxide in the ash was recalculated and is presented on a coal basis in the tables showing washability results. A head sample was riffled from the 14-mesh by 0 portion for proxi- mate analysis (moisture, ash, volatile matter, and fixed carbon), ultimate analysis (carbon, hydrogen, sulfur, nitrogen, ash, and oxygen) and determination of calorific value, fusibility of ash, major elements in ash, free-swelling index, Hardgrove grindability index, and sulfur forms and content (pyritic, organic, and total). For the two coarse sized samples, the separation was made in a screen bottom container which is inserted in 10-gallon-capacity vessels containing the organic liquid. The sample was placed in the 1.30 specific gravity bath, in small quantities to prevent entrapment, and was stirred a.nd allowed to separate. The lighter specific gravity coal fraction was removed from the surface of the bath with a screen wire strainer; the heavier specific gravity material settled to the container bottom which was then raised above the liquid level to drain. The container with the heavier specific gravity material was placed in the 1.40 specific gravity solution and the process was repeated. This procedure was continued until the sample was separated into the desired specific gravity fractions. For the 14-mesh by 0 size sample, the separation was made in glass separatory flasks joined by standard ground taper joints. After the sample separated, a stopper was passed through the float layer and inserted into the neck of the upper section of the separatory flask. The flask was then separated and both products were filtered. The "floats" were dried and prepared for analysis, while the "sinks" were reintroduced into another separatory flask containing a heavier specific gravity liquid and the float-sink procedure was repeated. Upon completion of the float-sink testing, the specific gravity fractions of the three sized samples were analyzed for calorific value, ash, pyritic sulfur, and total sulfur content. All product analyses are reported on a moisture-free basis unless otherwise noted. Raw coal moisture, as presented in the appendix tables, is the moisture contained in the sample after it was air dried at the coal preparation laboratory. The air dry loss is not included in the moisture determination. It is felt that under normal conditions the moisture content as reported here would closely simulate the moisture content of the coal burned at the powerplant. ------- Specific gravity separations of fine coal are particularly diffi- cult, especially with coals that are porous and contain high inherent moisture contents, because the heavy liquid used can penetrate the pores displacing the capillary held water, thus causing an increase in the apparent specific gravity of the coal. This may explain the unexpectedly low weight recoveries with some of the minus 14 mesh size fractions at specific gravity 1.30. The float-sink data from the channel samples do not necessarily represent the quality of the product loaded at the mine where the sample was taken but rather indicate the quality of the bed in that particular geographical location. Float-sink data are based upon theoretically perfect specific gravity separations that are approached but not equaled in commercial practice. To supplement the washability study, tests were carried out to demonstrate the sodium reduction potential of the lignite samples by ion exchange. In these empirical type tests, the sample was stirred for 5 minutes in a vessel with a solution containing the equivalent of 10 pounds of calcium chloride (CaCl2) per ton of dry lignite. All tests were performed at room temperature with the minus 14 mesh head samples and float 1.60 specific gravity fractions. After treatment, the pro- ducts were analyzed for the Na20 content of the ash. ARKANSAS LIGNITES Geology Lignite is known to occur in beds primarily of Tertiary age in a broad zone that extends from southwestern to northeastern Arkansas (figure 2). Rocks containing lignite are exposed in an area of about 6,125 square miles in the Gulf Coastal Plain of Arkansas. From oldest to youngest, these rocks are the Tokio group of Cretaceous age, and the Wilcox group, Claiborne group, and Jackson group of Eocene age. Beds of lignite are more abundant and generally thicker in the Wilcox group. These rocks contain numerous beds of lignite ranging from a fraction of a foot to more than 22 feet thick. The geology of the Arkansas lignite has been described by Haley (4J. Figure 3 is a generalized cross section of Paleocene and Eocene groups of formations of lignite in the southern part of Arkansas (_3). Reserves The estimate of the lignite reserves in Arkansas was prepared on a basis of original reserves of lignite before mining (table 2). The ------- CROW LEY'S RIDGE JOHNSON / K>ff I VAH IUHCN PRAIRIE ULASKI | LONOKE Little Rock 7J, JEFFEdSON ARKANSAS A^T i I f f CAST LIMIT OF ARKANSAS- WHITE-RED BASINS AREAS OF SHALLOW LIGNITE DEPOSITS From: G«ol. Mop of Arkansas, Ark. Seol. Surv., 1929 FIGURE 2. - Areas of shallow, lignite deposits in Arkansas. ------- WEST JACKSON AND CLAIBORNE \ L E G E r~] 6LMCONITE S3 LIMfSTONC LfNTILS SS COHCKCTIONS r~l StND I -'1 SMOY CD CLAY \?*3 LIGNlTf ^P%%^ > ^^IdEv FIGURE 3. - Generalized cross section. (Indicated lignite occurrences are not drawn to scale nor are they specifically located) ------- original reserves of lignite in known deposits are estimated to be 32 million short tons (11). This estimated total pertains to known de- posits of lignite thicker than 30 inches and under less than 100 feet of overburden. TABLE 2. - Estimated original reserves of Arkansas lignite in deposits more than 30 inches thick and lying be- neath less than 100 feet of overburden (In thousands of short tons) County Bradley Calhoun. • Clark Clay Cleveland. Cross Dallas Grant Total (!) 300 . ... 200 , . . . 300 (:) . . . 200 .... C1) .... (X) . ... 4,900 , . . . 300 County Greene Hot Spring Ouachita Pulaski Saline Total Total . . . . 200 . . . . 300 , . . . 400 ... 5 200 , . . . 700 , . . . 12 500 . .. 6,500 , ... 32,000 Incomplete thickness data, or lignite less than 30 inch thick. Lignite under more than 100 feet of overburden has been found in cores from core drilling and in rock cuttings from wells drilled for oil throughout much of the Gulf Coastal Plain. The total reserves of lignite in Arkansas are tentatively estimated to be 350 million short tons. A more accurate estimate of the lignite reserves in Arkansas would be dependent upon data obtained by an intensive mapping and core-drilling program. Arkansas lignites have the following ranges of composition by proximate analyses: Moisture—23.4 to 52.4 percent; volatile material— 12 to 35 percent; fixed carbon—7.4 to 24.7 percent; and ash—6 to 57.2 percent. Heat values range from 2,770 to 7,560 Btu per pound. Production Lignite has been mined intermittently from about 1947 until 1960. Since then no lignite has been mined in Arkansas. Data pertaining to the amount of lignite mined in Arkansas are incomplete, but total cumu- lative production is estimated to be less than 100,000 short tons. TEXAS LIGNITES Geology The principal lignite deposits are found in the Wilcox Group (lower Eocene) which contains approximately 80 percent of the resources, while 10 ------- deposits of secondary importance are found in the Yegua Formation and Jackson Group (upper Eocene). Lignite occurs as a component facies of ancient fluvial, deltaic, and lagoonal rocks in East, Central, South- east, and South Texas. Lignite-bearing strata dip coastward at one-half to one degree. The highest grade and most extensive resources occur north of the Colorado River in the Wilcox Group of East and Central Texas (figure 4). There is a correlation between grade and geologic occurrence; deltaic lignite is the best grade, fluvial lignite is intermediate in grade, and lagoonal lignite is poorest in grade. The geology of the Texas lignites have been described by Kaiser (6) . A stratigraphic occurrence of the Texas lignites is shown in table 3. Resources Identified coal resources in Texas as of January 1, 1974, are set at 16,341 million short tons or about 1 percent of the U.S. total (_7_). Table 4 shows tbat more than half of the Texas resources are lignite (10,426 million tons) which occur at depths ranging from 0 to 200 feet in the lower Tertiary of the Gulf Coastal Plain. The remainder is bituminous coal (5,915 million tons) found at levels from 0 to 3,000 feet in three areas in Texas: North-Central, Rio Grande Embayment, and Trans-Pecos. The total statewide lignite resources of 10.4 billion short tons was calculated relying on geologic occurrence, past and current production, reported outcrop occurrences, and projection from deep-basin occurrences. Texas lignites have the following ranges of composition by proxi- mate analyses: moisture—27.5 to 32.3 percent; volatile matter—33.8 to 35.7 percent; fixed carbon—21.8 to 29.5 percent; and ash—9.1 to 11.0 percent. Heating values ranged 7,124 to 7,916 Btu per pound. Production Since about 1890, lignite has been produced by more than 150 opera- tors in at least 35 Texas counties. Reasonably reliable production figures to date are estimated at 125 million tons (6). All of the coal currently mined in Texas is strip-mined lignite from north of the Colorado River where zero to 180 feet of unconsoli- dated overburden is removed. Statewide production in 1976 was 12,300,000 tons, all of which is captive. The oldest producer is ICI America Inc., which has operated a mine in Harrison County at Darco since 1931 for the production of activated carbon. Texas Utilities Generating Company, a subsidiary of Texas Utilities, operates three mines; in Milam County at Alcoa, Freestone County near Fairfield, and Titus County near Monti- cello. These mines produce 2 to 6 million tons annually for steam- electric plants of 360 to 1,150 MW capacity. 11 ------- TEXAS NEAR-SURFACE LIGNITE YEGUA-JACKSON EXISTING AND PROPOSED MINING SITES 100 milit SCALE FIGURE 4. - Distribution of Texas near-surface lignite. 12 ------- TABLE 3. - Stratigraphic occurrence of Texas lignite1 w o p. en 3 ^5 O O Ll O O O i-f U i-l -H O Upper Middle Lower* Upper Yegua* Laredo Formation El Pico Clay Bigford Formation Carrizo Indio Formation* *Main lignite occurrences. Terminology from: Barnes, 1967, 1970, 1974b; Eargle, 1968; Renick, 1936. Raiser, W. R. Texas Lignite: Near-Surface and Deep-Basin Resources, Bureau of Economic Geology, R.I.-No. 79, 70 pp. 13 ------- TABLE 4. - Near-surface potential Texas lignite resources1 (In millions of short tons) County Angelina Aktascosa Jastrop Bexar Bowie Brazos Jurleson CaLdwell Fayette Franklin Freestone Grimes Guadalupe Harrison Henderson Hopkins Houston LaSalle Lee Limestone Madison Marion toverick •IcMullen Medina Milam Morris Nacogdoches Panola Rains Robertson Rusk Shelby Starr Uitus Trinity Uvalde Van Zandt Walker Washington Wood Zavala Zapata By County and Group Yegua- Wilcox Yegua Jackson Jackson 174 26 70 447 78 536 39 42 121 85 76 102 156 967 63 82 555 463 434 255 86 47 95 41 169 132 60 129 212 150 813 89 90 524 245 403 275 234 33 444 20 108 110 782 17 92 198 24 33 8,606 836 550 434 By Region and Geology Amount Percent Regions East Texas 5,085 48.77 Central Texas 2,846 27.30 Southeast Texas 1,386 13.29 South Texas 1,109 10.64 10,426 100.00 Geologic Occurrence Fluvial 4,709 45.17 Deltaic 4,232 40.59 Lagoonal 1,485 14.24 10,426 100.00 Geologic Trend Lower Eocene (Wilcox) 8,606 82.54 Upper Eocene (Yegua-Jackson) 1,820 17.46 10,426 100.00 i i iKaiser, W. R. Texas of; Economic Geology, Lignite: Near University of -Surface and Deep Basin Resources, Bureau Texas, RI No. 79, 1974. 14 ------- Exploration activity during the past two years has been feverish, and several major companies are actively exploring for lignite. Major emphasis continues to be on the Wilcox group; however, significant activity is occurring in the Yegua-Jackson group. Five new mines at Martin Lake, Forest Grove, Twin Oaks, Bryan, and San Miguel are scheduled to come on line in 1980 (1.) . They will provide mine-mouth powerplants with 28 million tons of lignite from the Wilcox and Yegua coalfields. EXPERIMENTAL RESULTS Chemical and physical analyses of the raw coal samples crushed to 14 mesh top size are presented in table 5. The evaluation of the wash- ability data for each coal tested in Arkansas and Texas includes a description of the coalbed section, the washability data, and a short discussion about the data. In some instances a specific gravity of separation is given to illustrate the attainment of a certain quality product. These decisions are arbitrary and should not be construed as suggesting optimum economical plant operating conditions. Results are also presented to show the potential of reducing the sodium-in-ash content of the lignite samples by ion exchange. Arkansas Lignite Channel sample No. 1 was collected from an uncorrelated formation, Wilcox Group (top bench), Dallas County, Arkansas. This coal was from a prospect mine undergoing a feasibility study. A section of the bed is described as follows: Inches Lignite Total thickness of bed 3 6 and sample ^Overlying bed: sand, gravel, clay; floor: fireclay. Table 6 shows the detailed washability analyses of sample No. 1. The composite washability sample contained an average of 11,275 Btu/lb, 11.2 percent ash, 0.44 percent pyritic sulfur, and 0.93 percent total sulfur. The sodium oxide content in the coal was 0.10 percent. Crush- ing this coal to 3/8 inch top size and removing the sink 1.30 specific gravity material would provide a product analyzing 11,567 Btu/lb, 8.8 15 ------- TABLE 5. - Chemical and physical analyses of raw coal channel samples Type of analysis1 Chemical analysis , percent Moisture, as received Equilibrium moisture Volatile matter Fixed Carbon Ash Sulfate sulfur Pyritic sulfur Organic sulfur Total sulfur Hydrogen Carbon Nitrogen Oxygen British thermal units per Distribution coefficient, Physical Analysis: Free-swelling index No. Hardgrove grindability Fusibility of ash, °F: pound ri index Initial deformation temperature Softening temperature Fluid temperature Major elements in ash, percent Si02 A1203 Fe203 Ti02 CaO MgO Na20 K20 Sulfites Arkansas Texas Sample Sample Sample Sample Sample Sample Sample Sample Sample Sample Sample No. 1 No. 2 No. 3 No. 4 No. 5 No. 6 No. 7 No. 8 No. 9 No. 10 No. 11 34.37 31.99 29.19 32.74 25.69 28.35 30.91 29.89 33.03 31.37 32.85 35.84 32.82 32.59 36.46 30.25 28.24 31.60 31.72 32.75 28.33 37.38 51.17 52.14 47.30 33.61 45.48 47.63 46.37 41.82 43.69 42.38 48.83 36.98 30.77 35.70 23.28 42.71 38.43 44.16 38.32 47.00 39.86 35.36 11.85 17.09 17.00 43.11 11.81 13.94 9.47 19.86 9.31 17.76 15.81 .01 .01 .01 .05 .02 .03 .01 .01 .04 .01 .01 .42 .02 .77 .14 .08 .22 .07 .19 .36 .09 .09 .56 .62 1.00 .85 .97 .86 .70 1.18 .97 .80 1.30 .99 .65 1.77 1.04 1.07 1.11 .78 1.38 1.37 .90 1.40 5.14 5.21 5.14 3.16 4.72 4.69 5.00 4.36 4.70 4.34 4.88 63.98 57.35 58.57 38.58 65.82 63.03 67.42 58.82 66.37 59.19 59.30 1.09 1.00 .94 .66 .99 1.12 1.21 .85 1.17 .93 1.03 16.95 18.70 15.88 13.47 15.59 16.11 16.12 14.75 17.08 16.89 17.57 11,423 10,030 10,408 6,672 11,231 10,920 11,487 10,113 11,285 10,126 10,500 .7 .7 .7 .7 .8 .8 .8 .8 .7 .8 .7 00000000000 55 71 53 82 57 57 60 56 63 56 45 2,280 2,350 2,430 2,910 2,140 2,140 2,080 2,400 2,080 2,140 2,300 2,380 2,400 2,480 2,910 2,170 2,190 2,110 2,450 2,110 2,190 2,350 2,490 2,450 2,540 2,910 2,200 2,240 2,140 2,520 2,140 2,250 2,410 50.71 43.89 51.99 56.68 29.83 39.63 30.77 40.06 28.98 46.88 51.56 23.38 26.02 24.89 29.04 14.71 16.97 13.41 25.64 12.82 18.86 22.63 6.01 7.15 16.59 3.58 5.29 5.43 4.76 2.57 9.15 4.00 4.58 2.33 1.33 1.00 1.00 2.33 1.00 1.12 1.67 1.67 1.67 1.00 8.40 11.19 1.12 3.08 18.19 15.39 24.10 12.59 16.79 13.29 7.64 1.53 1.23 .53 .96 9.12 2.75 4.79 2.72 5.54 2.95 1.69 .19 .19 .08 .27 .98 .67 1.13 .24 1.06 .65 1.27 .48 .24 .18 1.20 .05 .24 .27 .75 .24 .72 .65 6.11 8.17 .77 3.33 17.78 14.79 16.83 11.34 17.70 8.85 8.76 analyses are on moisture-free basis unless otherwise indicated. ------- TABLE 6. - Detailed washabillty analyses of sample No. 1 STATE: Arkansas COUNTY: Dallas FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 75.1 Float- 1.30 98.1 98.9 1.30 - 1.40 .7 .6 1.40 - 1.60 .8 .2 Sink - 1.60 .8 .3 Size fraction: 3/8 x 14 Weight percent: 18.9 Float- 1.30 92.0 95.2 1.30 - 1.40 3.6 2.9 1.40 - 1.60 1.9 1.2 Sink - 1.60 2.5 .7 Size fraction: 14 x 100 Weight percent: 6.0 Float- 1.30 74.5 80.9 1.30 - 1.40 13.2 12.8 1.40 - 1.60 6.1 4.6 Sink - 1.60 6.1 1.7 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 95.5 97.4 1.30 - 1.40 2.0 6.2 1.40 - 1.60 1.0 2.2 Sink - 1.60 1.5 .8 Minus 100 mesh 1.7 1.6 Btu/lb 11,539 9,140 7,046 4,036 11,528 9,101 6,814 2,970 11,571 10,296 8,078 2,954 11,538 9,581 7,344 3,412 10,583 Ash 9.9 26.1 41.3 61.1 9.0 25.5 41.4 69.0 8.4 17.2 32.2 69.4 9.7 22.4 38.0 65.8 20.9 Percent Pyritic sulfur 0.52 2.16 3.66 9.45 0.17 1.20 2.30 7.75 0.14 .36 .94 2.56 0.44 1.13 2.16 7.15 1.05 Total sulfur N3201 0.74 2.55 3.87 9.50 0.77 1.70 2.62 7.78 0.83 1.07 1.42 2.65 0.75 1.68 2.51 7.21 1.86 Cumulative Percent Recovery, pet. Weight Btu 98.1 98.8 99.2 100.0 92.0 95.6 97.5 100.0 74.5 87.8 93.9 100.0 95.5 97.6 98.5 100.0 100.0 98.9 99.5 99.7 100.0 95.2 98.2 99.3 100.0 80.9 93.7 98.3 100.0 97.4 98.9 99.6 100.0 100.0 Btu/lb 11,539 11,521 11,506 11,445 11,528 11,437 11,347 11,135 11,571 11,379 11,164 10,661 11,538 11,498 11,456 11,339 11,326 Ash 9.9 10.0 10.1 10.5 9.0 9.6 10.2 11.7 8.4 9.7 11.2 14.8 9.7 9.9 10.2 11.0 11.2 Pyritic sulfur 0.52 .53 .54 .62 0.17 .21 .25 .44 0.14 .17 .22 .37 0.44 .45 .47 .57 .58 Total sulfur 0.74 .75 .76 .84 0.77 .80 .84 1.02 0.83 .87 .90 1.01 0.75 .77 .79 .88 .90 Pounds, N3201 S02/MM Btu 1.3 1.3 1.3 1.5 1.3 1.4 1.5 1.8 1.4 1.5 1.6 1.9 1.3 1.3 1.4 1.6 1.6 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 6. - Detailed vashability analyses of sample No. 1 (Con.) STATE: Arkansas COUNTY: Dallas FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Btu/lb Percent Pyritic Ash sulfur Total sulfur N3201 Weight percent: 63.9 Float- 1.30 95.5 1.30 - 1.40 2.4 1.40 - 1.60 .8 Sink - 1.60 1.3 97.1 2.1 .5 .4 11,529 9,758 7,110 3,215 9.0 21.5 39.0 66.0 0.15 1.20 4.49 14.64 0.77 Cumulative Percent Recovery, pet. Weight Btu 95.5 1.85 , 97.9 4.71 ; 98.7 14.70 ': 100.0 Size fraction: 14 x 100 Weight percent: 36.1 Float- 1.30 89.3 1.30 - 1.40 6.9 1.40 - 1.60 2.0 Sink - 1.60 1.8 Size composite: 3/8 Weight percent: 100. Float- 1.30 93.3 1.30 - 1.40 4.0 1.40 - 1.60 1.2 Sink - 1.60 1.5 Minus 100 mesh 10.2 TOP SIZE: 14 Size fraction: 14 x Weight percent: 100. Float- 1.30 90.3 1.30 - 1.40 5.1 1.40 - 1.60 2.3 Sink - 1.60 2.3 92.2 5.9 1.4 .6 x 100 0 95.4 4.4 1.0 .5 8.8 0 0 93.5 4.4 1.6 .5 11,639 9,699 7,728 3,438 11,567 9,721 7,477 3,313 10,677 11,633 9,776 7,649 2,609 8.5 21.7 34.3 64.0 8.8 ?1.6 36.2 65.1 15.6 8.6 20.6 36.1 72.7 0.12 .57 1.67 4.36 0.14 .81 2.81 10.10 .41 0.12 .48 1.35 9.36 0.62 89.3 1.03 96.2 1.78 98.2 4.56 100.0 0.72 93.3 1.35 97.3 2.97 98.5 10.23 100.0 .95 100.0 : 0.71 0.09 1.08 .17 1.90 .26 9.40 .20 90.3 95.4 97.7 100.0 97.1 99.1 99.6 100.0 92.2 98.1 99.4 100.0 95.4 98.8 99.6 100.0 100.0 93.5 97.9 99.5 100.0 Btu/lb 11,529 11,485 11,451 11,342 11,639 11,500 11,424 11,277 11,567 11,490 11,441 11,318 11,259 11,633 11,534 11,443 11,239 Ash 9.0 9.3 9.5 10.3 8.5 9.4 9.9 10.9 8.8 9.4 9.7 10.5 11.0 8.6 9.2 9.9 11.3 Pyritic sulfur 0.15 .18 .21 .40 0.12 .15 .18 .26 0.14 .17 .20 .35 .35 0.12 .14 .17 .38 Total sulfur N3201 0.77 .80 .83 1.01 0.62 .65 .67 .74 0.72 .74 .77 .91 .92 0.71 0.09 .73 .09 .76 .09 .96 .10 Pounds, S02/MM Btu 1.3 1.4 1.4 1.8 1.1 1.1 1.2 1.3 1.2 1.3 1.3 1.6 1.6 1.2 1.3 1.3 1.7 Sodium oxide performed only on 14 mesh x 0 sample. ------- percent ash, 0.14 percent pyritic sulfur, and 0.72 percent total sulfur at a Btu recovery of 95.4 percent. This coal would now meet the current S02 emission standard. Channel sample No. 2 was collected from an uncorrelated formation, Wilcox Group (bottom bench), Dallas County, Arkansas. This coal is from a prospect mine undergoing a feasibility study. A section of the bed is described as follows: Inches Lignite Total thickness of bed 9 6 and sample *0verlying bed: clay, floor: silty clay. Table 7 shows the detailed washability analyses of sample No. 2. The composite washability sample contained an average of 10,344 Btu/lb, 17.2 percent ash, 0.03 percent pyritic sulfur, and 0.69 percent total sulfur. The sodium oxide content in the coal was 0.04 percent. Crush- ing this coal to 1-1/2 inches top size and removing the sink 1.40 specific gravity material would provide a product analyzing 10,786 Btu/lb, 14.0 percent ash, 0.02 percent pyritic sulfur, and 0.67 percent total sulfur at a Btu recovery of 97.3 percent. This coal would now meet the EPA SC>2 emission standard of 1.2 pounds/MM Btu. Channel sample No. 3 was collected from an uncorrelated formation, Wilcox Group, Ouachita County, Arkansas. A section of the bed is described as follows: Bed Section1 Feet Inches Lignite 2 7 Total thickness of bed 2 7 and sample Overlying bed: sandstone; floor: fireclay. Table 8 shows the detailed washability analyses of sample No. 3. The composite washability sample contained an average of 10,602 Btu/lb, 15.5 percent ash, 0.77 percent pyritic sulfur, and 1.59 percent total sulfur. The sodium oxide content in the coal was 0.01 percent. This sample contained an average of 0,82 percent organic sulfur and could not be upgraded to meet the emission standard of 1.2 pounds S02/MM Btu. Crushing to 1-1/2 inches top size and removing the sink 1.30 specific 19 ------- TABLE 7. - Detailed washability analyses of sample No. 2 -STATE: Arkansas COUNTY: Dallas FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 72.8 Float- 1.30 87.9 91.8 1.30 - 1.40 8.1 6.6 1.40 - 1.60 2.1 1.2 Sink - 1.60 1.9 .4 Size fraction: 3/8 x 14 Weight percent: 22.0 Float- 1.30 85.0 90.6 1.30 - 1.40 7.6 6.5 1.40 - 1.60 3.6 2.0 Sink - 1.60 3.7 .9 Size fraction: 14 x 100 Weight percent: 5.2 Float- 1.30 65.3 72.4 1.30 - 1.40 4.7 5.0 1..40 - 1.60 21.0 19.3 Sink - 1.60 9.0 3.3 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 86.1 90.8 1.30 - 1.40 7.8 6.5 1.40 - 1.60 3.4 7.1 Sink - 1.60 2.6 1.1 Minus 100 mesh 1.9 1.2 Btu/lb 10,915 8,507 5,723 2,491 11,150 8,865 5,854 2,397 11,279 10,847 9,365 3,777 10,980 8,656 6,909 2,689 6,696 Ash 13.1 29.8 48.7 70.7 11.6 27.1 47.3 71.0 10.9 13.5 20.6 61.8 12.7 28.7 39.5 69.2 46.8 Percent Pyritic sulfur 0.02 .02 .02 .01 0.02 .02 .02 .08 0.03 .04 .03 .29 0.02 .02 .02 .08 .12 Total sulfur N3201 0.68 .61 .50 .29 0.66 .69 .50 .34 0.68 .69 .73 .63 0.68 .63 .57 .37 .50 Cumulative Percent Recovery Weight 87.9 96.0 98.1 100.0 85.0 92.7 96.3 100.0 65.3 70.0 91. 0 100.0 86.1 93.9 97.4 100.0 100.0 , pet. Btu 91.8 98.4 99.6 100.0 90.6 97.1 99.1 100.0 72.4 77.4 96.7 100.0 90.8 97.3 99.3 100.0 100.0 Btu/lb 10,915 10,711 10,603 10,452 11,150 10,962 10,769 10,458 11,279 11,250 10,815 10,183 10,980 10,786 10,649 10,439 10,368 Ash 13.1 14.5 15.3 16.3 11.6 12.9 14.2 16.3 10.9 11.1 13.3 17.6 12.7 14.0 14.9 16.4 16.9 Pyritic sulfur 0.02 .02 .02 .02 0.02 .02 .02 .02 0.03 .03 .03 .05 0.02 .02 .02 .02 .02 Total sulfur N3201 0.68 .67 .67 .66 0.66 .66 .66 .64 0.68 .68 .69 .69 0.68 .67 .67 .66 .66 Pounds, S02/MM Btu 1.2 1.3 1.3 1.3 1.2 1.2 1.2 1.2 1.2 1.2 1.3 1.3 1.2 1.2 1.3 1.3 1.3 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 7. - Detailed washabllity analyses of sample No. 2 (Con.) STATE: Arkansas COUNTY: Dallas FORMATION: tlncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 69.1 Float- 1.30 84.8 89.1 1.30 - 1.40 10.0 8.5 1.40 - 1.60 2.8 1.8 Sink - 1.60 2.5 .6 Size fraction: 14 x 100 Weight percent: 30.9 Float- 1.30 72.5 78.2 1.30 - 1.40 18.5 17.4 1.40 - 1.60 4.9 3.5 Sink - 1.60 4.0 1.0 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 81.0 86.1 1.30 - 1.40 12.6 12.5 1.40 - 1.60 3.4 2.5 Sink - 1.60 3.0 .8 Minus 100 mesh 11.6 8.4 TOP SIZE: Ht Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 78.4 84.2 1.30 - 1.40 14.3 13.0 1.40 - 1.60 3.9 2.5 Sink - 1.60 3.5 .4 Btu/lb 11,071 8,982 6,773 2,607 11,230 9,751 7,293 2,617 11,115 9,331 7,004 2,611 8,350 11,157 9,440 6,541 1,244 Ash 12.3 26.4 41.2 68.0 11.0 20.1 36.3 68.3 11.9 23.5 39.0 68.1 33.4 12.0 22.0 42.4 81.6 Percent Pyritic sulfur 0.05 .04 .04 .04 0.01 .02 .02 .12 0.04 .03 .03 .07 .04 0.02 .02 .02 .24 Total sulfur N3201 0.67 .64 .46 .29 0.71 .70 .53 .34 0.68 .67 .49 .31 .52 0.68 0.04 .73 .05 .41 .03 3.32 .01 Cumulative Percent Recovery, pet. Weight Btu 84.8 94.8 97.5 100.0 72.5 91.0 96.0 100.0 81.0 93.6 97.0 100.0 100.0 78.4 92.6 96.5 100.0 89.1 97.6 99.4 100.0 78.2 95.5 99.0 100.0 86.1 97.0 99.3 100.0 100.0 84.2 97.1 99.6 100.0 Btu/lb 11,071 10,851 10,735 10,535 11,230 10,929 10,742 10,414 11,115 10,874 10,737 10,497 10,275 11,157 10,892 10,717 10,389 Ash 12.3 13.8 14.6 15.9 11.0 12.9 14.1 16.2 11.9 13.5 14.4 16.0 17.8 12.0 13.5 14.7 17.0 Pyritic sulfur 0.05 .05 .05 .05 0.01 .01 .01 .02 0.04 .04 .04 .04 .04 0.02 .02 .02 .03 Total sulfur Na20J 0.67 .67 .66 .65 0.71 .71 .70 .68 0.68 .68 .67 .66 .65 0.68 0.04 .69 .04 .68 .04 .77 .04 Pounds, S02/MM Btu 1.2 1.2 1.2 1.2 1.3 1.3 1.3 1.3 1.2 1.2 1.3 1.3 1.3 1.2 1.3 1.3 1.5 Sodium oxide performed only on 14 mesh x 0 sample ------- TABLE 8. - Detailed washability analyses of sample No. 3 STATE: Arkansas COUNTY: Ouachita FORMATION: Uncorrelated GROUP: Wilcox Direct ! Cumulative Percent Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 77.6 Float- 1.30 93.3 95.2 1.30 - 1.40 4.0 3.2 1.40 - 1.60 .9 .7 Sink - 1.60 1.8 .9 Size fraction: 3/8 x 14 Weight percent: 16.2 Float- 1.30 86.1 89. A 1.30 - 1.40 9.4 8.1 1.40 - 1.60 2.8 2.0 Sink - 1.60 1.7 .6 Size fraction: 14 x 100 Weight percent: 6.2 Float- 1.30 28.4 52.3 1.30 - 1.40 20.1 32.3 1.40 - 1.60 8.7 10.9 Sink - 1.60 42.8 4.6 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 88.1 93.5 1.30 - 1.40 5.9 10.6 1.40 - 1.60 1.7 4.3 Sink - 1.60 4.3 3.1 Minus 100 mesh 1.5 1.0 Btu/lb 11,249 8,896 7,968 5,409 11,226 9,311 7,771 2,920 11,667 10,198 7,964 681 11,253 9,278 7,914 2,347 7,047 Ash 11.4 26.1 30.8 46.8 10.5 21.3 31.1 65.4 9.2 15.3 28.4 92.7 11.2 22.6 30.1 76.2 40.8 Pyritic sulfur 0.24 2.24 8.23 25.84 0.21 .86 4.09 13.48 0.08 .21 .73 .31 0.23 1.45 4,74 9.38 .43 Total sulfur NaaO1 1.13 3.07 9.15 26.33 1.15 1.90 5.45 13.95 1.10 1.23 1.73 .32 1.13 2.38 5.81 9.57 1.23 Recovery Weight 93.3 97.3 98.2 100.0 86.1 95.6 98.3 100.0 28.4 48.5 57.2 100.0 88.1 94.0 95.7 100.0 100.0 . pet. Btu 95.2 98.5 99.1 100.0 89.4 97.6 99.5 100.0 52.3 84.5 95.4 100.0 93.5 97.9 99.1 100.0 100.0 Btu/lb 11,249 11,152 11,123 11,020 11,226 11,037 10,945 10,810 11,667 11,059 10,590 6,342 11,253 11,130 11,073 10,697 10,643 Ash 11.4 12.0 12.2 12.8 10.5 11.6 12.1 13.0 9.2 11.7 14.3 47.9 11.2 11.9 12.2 15.0 15.4 Percent Pyritic sulfur 0.24 .32 .40 .85 0.21 .27 .38 .60 0.08 .13 .22 .26 0.23 .31 .39 .77 .77 Total sulfur N3201 1.13 1.21 1.28 1.73 1.15 1.22 1.34 1.55 1.10 1.15 1.24 .85 1.13 1.21 1.29 1.65 1.64 Pounds, S02/MM Btu 2.0 2.2 2.3 3.1 2.0 2.2 2.5 2.9 1.9 2.1 2.3 2.7 2.0 2.2 2.3 3.1 3.1 'Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 8. - Detailed washabllity analyses of sample No. 3 (Con.) STATE: Arkansas COUNTY: Ouachita FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 61.6 Float- 1.30 87.8 91.1 1.30 - 1.40 7.2 6.0 1.40 - 1.60 2.7 2.0 Sink - 1.60 2.3 .9 Size fraction: 14 x 100 Weight percent: 38.4 Float- 1.30 55.9 64.9 1.30 - 1.40 27.8 28.0 1.40 - 1.60 6.5 5.3 Sink - 1.60 9.8 1.8 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 75.5 83.7 1.30 - 1.40 15.1 21.6 1.40 - 1.60 4.2 4.0 Sink - 1.60 5.2 1.5 Minus 100 mesh 12.6 10.8 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 77.7 84.1 1.30 - 1.40 12.7 11.5 1.40 - 1.60 3.8 2.6 Sink - 1.60 5.9 1.8 Btu/lb 11,269 9,083 7,906 4,029 11,757 10,195 8,195 1,843 11,407 9,868 8,080 2,448 10,134 11,520 9,700 7,322 3,188 Ash 11.0 24.8 31.3 55.7 8.4 16.3 27.6 82.3 10.3 18.8 29.1 74.9 18.7 9.5 18.7 35.0 67.8 Percent Pyritic sulfur 0.18 1.04 6.17 24.18 0.13 .32 1.34 2.80 0.17 .53 3.26 8.72 .63 0.13 0.31 2.47 9.14 Total sulfur Na201- 0.96 1.85 6.40 24.18 0.95 1.16 2.13 2.95 0.96 1.36 3.82 8.83 1.44 1.01 0.01 1.11 .01 3.20 .01 9.24 .01 Cumulative Percent Recovery, pet. Weight Btu 87.8 95.0 97.7 100.0 55.9 83.7 90.2 100.0 75.5 90.6 94.8 100.0 100.0 77.7 90.4 94.1 100.0 91.1 97.2 99.1 100.0 64.9 92.9 98.2 100.0 83.7 95.7 98.8 100.0 100.0 84.1 95.6 98.2 100.0 Btu/lb 11,269 11,103 11,015 10,852 11,757 11,238 11,018 10,121 11,407 11,151 11,016 10,571 10,522 11,520 11,265 11,107 10,642 Ash 11.0 12.0 12.6 13.6 8.4 11.0 12.2 19.1 10.3 11.7 12.4 15.7 16.0 9.5 10.8 11.8 15.0 Pyritic sulfur 0.18 .25 .41 .96 0.13 .19 .28 .52 0.17 .23 .36 .79 .78 0.13 .16 .25 .77 Total sulfur N3201 0.96 1.03 1.17 1.71 0.95 1.02 1.10 1.28 0.96 1.02 1.15 1.55 1.53 1.01 0.01 1.02 .01 1.11 .01 1.59 .01 Pounds, S02/l*i Btu 1.7 1.9 2.1 3.2 1.6 1.8 2.0 2.5 1.7 1.8 2.1 2.9 2.9 1.8 1.8 2.0 3.0 ^Sodium oxide performed only on 14 mesh x 0 sample. ------- gravity material would reduce the pyritic sulfur content 70 percent and reduce the S02 emissions from 3.1 to 2.0 pounds/MM Btu at a Btu recovery of 93.5 percent. This sample was taken from an outcropping near an abandoned strip mine. Channel sample No. 4 was collected from an uncorrelated formation, Wilcox Group, Saline County, Arkansas. A section of the bed is de- scribed as follows: Bed Section1 Feet Inches Carbonaceous shale 0 2 Lignite 2 11 Total thickness of bed and 3 1 sample Overlying bed: shale; floor: fireclay. Table 9 shows the detailed washability analyses of sample No. 4. The composite washability sample contained an average of 6,410 Btu/lb, 41.0 percent ash, 0.15 percent pyritic sulfur, and 1.07 percent total sulfur. The sodium oxide content in the coal was 0.08 percent. This sample could not be upgraded to meet the current S0£ emission standard since it contained an average of 0.92 percent organic sulfur. This sample was taken from a lignite bed associated with a bauxite mine. The lignite, however, is not being mined at this time. Texas Lignite Channel sample No. 5 was collected from the Lower Calvert forma- tion, Wilcox Group, Freestone County, Texas. A section of the bed is described as follows: Bed Section1 Feet Inches Lignite 5 6 Total thickness of bed 5 6 and sample 10verlying bed: shale; floor: fireclay. Table 10 shows the detailed washability analyses of sample No. 5. The composite washability sample contained an average of 11,213 Btu/lb, 10.2 percent ash, 0.09 percent pyritic sulfur, and 1.02 percent total sulfur. The sodium oxide content of the coal was 0.06 percent. This coal could not be upgraded to meet the current S02 emission standard 24 ------- TABLE 9. - Detailed washabllity analyses of sample No. 4 STATE: Arkansas COUNTY: Saline FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet . Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 80.8 Float- 1.30 46.0 62.5 1.30 - 1.40 13.1 14.0 .1.40 - 1.60 20.9 15. 7 Sink - 1.60 20.0 7.8 Size fraction: 3/8 x 14 Weight percent: 15.0 Float- 1.30 32.9 49.7 1.30 - 1.40 14.0 17.0 1.40 - 1.60 26.6 23.4 Sink - 1.60 26.5 9.9 Size fraction: 14 x 100 Weight percent: 4.1 Float- 1.30 17.2 30.5 1.30 - 1.40 11.3 17.2 1.40 - 1.60 25.1 29.1 Sink - 1.60 46.4 23.1 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 42.8 60.5 1.30 - 1.40 13.1 14.6 1.40 - 1.60 22.0 17.8 Sink - 1.60 22.1 9.5 Minus 100 mesh 1.0 .1.0 Btu/lb 9,072 7,165 5,011 2,592 9,519 7,655 5,556 2,351 10,042 8,633 6,584 2,828 9,139 7,296 5,184 2,569 6,475 Ash 19.5 34.6 f.2.8 70.2 17.3 31.3 48.6 71.9 13.8 24.4 39.3 67.7 19.2 33.7 51.4 70.3 42.4 Percent Pyritic sulfur 0. 20 .15 .10 .08 0.14 .12 .16 .47 0.09 .11 .18 .59 0.19 .14 .11 .19 .67 Total sulfur N3201 1.59 1.25 .77 .43 1.50 1.30 .96 .77 1.56 1.39 1.15 .87 1.58 1.26 .82 .53 1.52 Cumulative Percent Recover Weight 46.0 59.0 80.0 100.0 32.9 46.9 73.5 100.0 17.2 28.5 53.6 100.0 42.8 55.9 77.9 100.0 100.0 Btu 62.5 76.5 92.2 100.0 49.7 66.7 90.1 100.0 30.5 47.7 76.9 100.0 60.5 74.6 91.5 100.0 100.0 Btu/lb 9,072 8,650 7,697 6,674 9,519 8,963 7,720 6,306 10,042 9,483 8,127 5,668 9,139 8,707 7,714 6,576 6,575 Ash 19.5 22.8 30.7 38.6 17.3 21.5 31.3 42.0 13.8 18.0 28.0 46.4 19.2 22.6 30.7 39.4 39.5 Pyritic sulfur 0.20 .19 .17 .15 0.14 .13 .14 .23 0.09 .10 .14 .35 0.19 .18 .16 .17 .17 Total sulfur 1.59 1.51 1.32 1.14 1.50 1.44 1.27 1.14 1.56 1.49 1.33 1.12 1.58 1.50 1.31 1.14 1.14 Pounds, N3201 S02/MM Btu 3.5 3.5 3.4 3.4 3.2 3.2 3.3 3.6 3.1 3.1 3.3 3.9 3.5 3.5 3.4 3.5 3.5 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 9. - Detailed washability analyses of sample No. 4 (Con.) STATE: Arkansas COUNTY: Saline FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 76.0 Float- 1.30 40.9 58.7 1.30 - 1.40 13.4 14.9 1.40 - 1.60 21.1 17.4 Sink - 1.60 24.7 9.0 Size fraction: 14 x 100 Weight percent: 24.0 Float- 1.30 23.1 38.0 1.30 - 1.40 15.5 21.0 1.40 - 1.60 21.6 22.0 Sink - 1.60 39.8 19.0 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 36.6 55.6 1.30 - 1.40 13.9 16.6 1.40 - 1.60 21.2 18.5 Sink - 1.60 28.3 12.4 Minus 100 mesh 5.6 4.8 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 26.7 42.3 1.30 - 1.40 15.7 20.4 1.40 - 1.60 28.3 25.6 Sink - 1.60 29.4 11.7 Btu/lb 9,552 7,418 5,472 2,423 9,873 8,107 6,118 2,871 9,600 7,602 5,629 2,574 5,880 9,830 8,032 5,607 2,479 Ash 17.8 34.2 50.3 71.4 14.4 27.6 41.9 67. 4 17.3 32.4 48.3 70.1 45.2 16.1 29.4 48.1 71.2 Percent Pyritic sulfur 0.13 .12 .15 .11 .08 .12 .15 .24 0.12 .12 .1^ .15 .49 0.09 .10 .14 .17 Total sulfur N3201 1.52 1.23 .90 .39 1.52 1.35 .98 .61 1.52 1.26 .92 .46 1.29 1.47 0.06 1.35 .07 .95 .09 .45 .11 Cumulative Percent Recovery Weight 40.9 54.3 75.3 100.0 23.1 38.6 60.2 100.0 36.6 50.5 71.7 100.0 100.0 26.7 42.4 70.6 100.0 , pet. Btu 58.7 73.7 91.0 100.0 38.0 59.0 81.0 100.0 55.6 71.0 89.0 100.0 100.0 42.3 62.7 88.3 100.0 Btu/lb 9,552 9,025 8,031 6,649 9,873 9,163 8,072 6,002 9,600 9,050 8,039 6,493 6,461 9,830 9,164 7,741 6,196 Ash 17.8 21.8 29.8 40.1 14.4 19.7 27.7 43.5 17.3 21.5 29.4 40.9 41.1 16.1 21.0 31.9 43.4 Pyritic sulfur 0.13 .13 .13 .13 0.08 .10 .12 .16 0.12 .12 .13 .14 .16 0.09 .09 .11 .13 Total sulfur N3201 1.52 1.45 1.29 1.07 1.52 1.45 1.28 1.01 1.52 1.45 1.29 1.06 1.07 1.47 0.06 1.43 .06 1.24 .07 1.00 .08 Pounds, S02/MM Btu 3.2 3.2 3.2 3.2 3.1 3.2 3.2 3.4 3.2 3.2 3.2 3.3 3.3 3.0 3.1 3.2 3.2 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABL.E 10. - Detailed washability analyses of sample No. 5 STATE : Texas COUNTY: Freestone FORMATION: Lower Calvert GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 77.7 Float- 1.30 96.8 97.2 1.30 - 1.40 2.8 2.6 1.40 - 1.60 .2 .2 Sink - 1.60 .2 .1 Size fraction: 3/8 x 14 Weight percent: 17.9 Float- 1.30 68.2 70.6 1.30 - 1.40 28.2 27.3 1.40 - 1.60 2.0 1.6 Sink - 1.60 1.6 .4 Size fraction: 14 x 100 Weight percent: 4.4 Float- 1.30 7.5 8.4 1.30 - 1.40 69.0 74.1 1.40 - 1.60 15.6 15.1 Sink - 1.60 7.9 2.4 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 87.7 93.1 1.30 - 1.40 10.3 35.9 1.40 - 1.60 1.2 9.2 Sink - 1.60 .8 1.2 Minus 100 mesh .6 .5 Btu/lb 11,303 10,331 8,710 4,717 11,419 10,679 8,897 3,004 11,927 11,311 10,210 3,143 11,321 10,802 9,626 3,396 9,893 Ash 9.7 16.3 29.2 50.6 8.4 12.6 25.5 63.0 7.8 8.2 14.5 55.0 9.5 12.1 19.7 57.1 19.8 Percent Pyritic sulfur 0.01 .02 .35 19.99 0.04 .02 .08 8.86 0.13 .02 .03 1.06 0.01 .02 .09 7.56 .13 Total sulfur Na20L 0.77 .77 1.62 22.20 0.97 0.89 .76 10.01 1.11 .98 .88 1.69 0.80 .89 .94 8.68 1.12 Cumulative Percent Recovery, pet. Weight Btu 96.8 99.6 99.8 100.0 68.2 96.4 98.4 100.0 7.5 76.5 92.1 100.0 87.7 98.0 99.2 100.0 100.0 97.2 99.8 99.9 100.0 70.6 97.9 99.6 100.0 8.4 82.5 97.6 100.0 93.1 98.8 99.8 100.0 100.0 Btu/lb 11,303 11,277 11,272 11,259 11,419 11,203 11,155 11,024 11,927 11,371 11,174 10,537 11,321 11,266 11,247 11,184 11,177 Ash 9.7 9.9 9.9 10.0 8.4 9.6 10.0 10.8 7.8 8.2 9.2 12.9 9.5 9.8 9.9 10.3 10.3 Pyritic sulfur 0.01 .01 .01 .05 0.04 .03 .04 .18 0.13 .03 .03 .11 0.01 .02 .02 .08 .08 Total sulfur N3201 0.77 .77 .77 .81 0.97 .95 .94 1.09 1.11 .99 .97 1.03 0.80 .81 .81 .87 .87 Pounds, SOo/MM Btu 1.4 1.4 1.4 1.4 1.7 1.7 1.7 2.0 1.9 1.7 1.7 2.0 1.4 1.4 1.4 1.6 1.6 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 10. - Detailed washability analyses of sample No. 5 (Con.) STATE: Texas COUNTY: Freestone FORMATION: Lower Calvert GROUP: Wilcox NJ OO Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 65.3 Float- 1.30 79.1 80.6 1.30 - 1.40 19.1 18.2 1.40 - 1.60 1.1 .9 Sink - 1.60 .7 .2 Size fraction: 14 x 100 Weight percent: 34.7 Float- 1.30 20.4 21.9 1.30 - 1.40 67.4 68.4 1.40 - 1.60 10.0 9.0 Sink - 1.60 2.2 .8 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 58.7 73.5 1.30 - 1.40 35.8 50.9 1.40 - 1.60 4.2 7.6 Sink - 1.60 1.2 .6 Minus 100 mesh 10.3 9.1 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 22.0 23.2 1.30 - 1.40 66.7 68.0 1.40 - 1.60 9.2 8.2 Sink - 1.60 2.2 .6 Btu/lb 11,441 10,708 9,217 4,064 11,889 11,249 10,041 3,883 11,494 11,060 9,894 3,949 10,875 11,975 11,528 10,089 3,112 Ash 8.0 13.3 24.2 57.8 6.9 8.8 16.3 57.0 7.9 10.4 17.7 57.3 13.2 7.2 8.6 16.0 63.4 Percent Pyritic sulfur 0.01 .01 .05 14.52 0.05 .03 .02 1.70 0.01 .02 .03 6.43 .06 0.03 .02 .03 3.06 Total sulfur Na.^1 0.97 .95 .80 15.99 1.05 .98 .87 2.17 0.98 .97 .86 7.27 1.02 0.97 0.03 .98 .08 .90 .07 3.68 .06 Cumulative Percent Recovery Weight 79.1 98.2 99.3 100.0 20.4 87.8 97.8 100.0 58.7 94.6 98.8 100.0 100.0 22.0 88.7 97.8 100.0 . Pet. Btu 80.6 98.8 99.8 100.0 21.9 90.2 99.2 100.0 73.5 96.0 99.6 100.0 100.0 23.2 91.2 99.4 100.0 Btu/lb 11,441 11,298 11,274 11,225 11,889 11,398 11,259 11,097 11,494 11,330 11,269 11,180 11,152 11,975 11,639 11,494 11,311 Ash 8.0 9.0 9.2 9.5 6.9 8.4 9.2 10.2 7.9 8.8 9.2 9.8 10.1 7.2 8.3 9.0 10.2 Pyritic sulfur 0.01 .01 .01 .11 0.05 .03 .03 .07 0.01 .02 .02 .10 .09 0.03 .02 .02 .09 Total sulfur Na201 0.97 .97 .96 1.07 1.05 1.00 .98 1.01 0.98 .98 .97 1.05 1.04 0.97 0.03 .98 .06 .97 .06 1.03 .06 Pounds, S02/MM Btu 1.7 1.7 1.7 1.9 1.8 1.7 1.7 1.8 1.7 1.7 1.7 1.9 1.9 1.6 1.7 1.7 1.8 1Sodium oxide performed only on 14 mesh x 0 sample. ------- since the average organic sulfur content was 0.93 percent. This coal contained relatively low ash and there would be little benefit to fine size crushing. None of this coal is washed. Channel sample No. 6 was collected from the Lower Calvert forma- tion, Wilcox Group, Freestone County, Texas. A section of the bed is described as follows: Bed Section1 Feet Inches Lignite 5 4 Total thickness of bed 5 4 and sample 10verlying bed: shale; floor: fireclay. Table 11 shows the detailed washability analyses of sample No. 6. The composite washability sample contained an average of 10,851 Btu/lb, 13.3 percent ash, 0.36 percent pyritic sulfur, and 1.16 percent total sulfur. The sodium oxide content in the coal was 0.03 percent. Since this coal contained an average of 0,80 percent organic sulfur, it could not be upgraded to meet the current S02 emission standard. Crushing to 14 mesh top size and removing the sink 1.40 specific gravity material would provide a product analyzing 9.9 percent ash which would represent an ash reduction of 27 percent. None of this coal is washed. Channel sample No. 7 was collected from an uncorrelated formation, Wilcox Group, Harrison County, Texas. A section of the bed is described as follows: Bed Section1 Feet Inches Lignite 7 2 Total thickness of bed 7 2 and sample Overlying bed: shale; floor: fireclay. Table 12 shows the detailed washability analyses of sample No. 7. The composite washability sample contained an average of 11,263 Btu/lb, 9.3 percent ash, 0.07 percent pyritic sulfur, and 0.80 percent total sulfur. The sodium oxide content in the coal was 0.11 percent. This sample could not be upgraded to meet the current S02 emission standard since it contained an average of 0.73 percent organic sulfur. The ash content of this coal was low and crushing would provide minimal benefit. None of this coal is washed. 29 ------- TABLE 11. - Detailed washabillty analyses of sample No. 6 STATE: Texas COUNTY: Freestone FORMATION: Lower Calvert GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 77.3 Float- 1.30 84.7 87.5 1.30 - 1.40 11.0 10.0 1.40 - 1.60 2.9 1.9 Sink - 1.60 1.3 .5 Size fraction: 3/8 x 14 Weight percent: 18.7 Float- 1.30 73.0 77.6 1.30 - 1.40 18.9 18.0 1.40 - 1.60 4.3 3.0 Sink - 1.60 3.8 1.4 Size fraction: 14 x 100 Weight percent: 3.9 Float- 1.30 9.0 10.6 1.30 - 1.40 64.1 70.9 1.40 - 1.60 14.6 13.6 Sink - 1.60 12.3 5.0 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 79.6 85.5 1.30 - 1.40 14.6 22.5 1.40 - 1.60 3.7 4.0 Sink - 1.60 2.2 1.8 Minus 100 mesh .7 .6 Btu/lb 11,249 9,869 7,112 4,538 11,351 10,150 7,515 3,907 11,884 11,246 9,478 4,152 11,269 10,175 7,572 4,250 9,357 Ash 10.5 20.0 40.2 53.8 9.1 17.6 36.0 55.2 7.2 9.8 20.0 54.3 10.2 17.7 36.1 54.4 24.0 Percent Pyritic sulfur 0.11 .17 .55 7.81 0.09 .22 .72 10.16 0.10 .09 .29 3.09 0.11 .17 .55 7.53 .61 Total sulfur N3201 0.97 .99 1.20 7.81 0.99 1.06 1.31 10.19 1.02 .98 1.06 3.84 0.97 1.01 1.20 7.70 1.45 Cumulative Percent Recovery Weight 84.7 95.8 98.7 100.0 73.0 91.9 96.2 100.0 9.0 73.2 87.7 100.0 79.6 94.2 97.8 100.0 100.0 , pet. Btu 87.5 97.5 99.5 100.0 77.6 95.6 98.6 100.0 10.6 81.4 95.0 100.0 85.5 96.7 99.1 100.0 100.0 Btu/lb 11,249 11,090 10,972 10,888 11,351 11,104 10,943 10,678 11,884 11,325 11,018 10,177 11,269 11,099 10,967 10,820 10,811 Ash 10.5 11.6 12.4 13.0 9.1 10.9 12.0 13.6 7.2 9.5 11.2 16.5 10.2 11.4 12.3 13.2 13.3 Pyritic sulfur 0.11 .12 .13 .23 0.09 .12 .14 .52 0.10 .09 .12 .49 0.11 .12 .13 .29 .30 Total sulfur N3201 0.97 .97 .98 1.07 0.99 1.00 1.02 1.36 1.02 .98 1.00 1.35 0.97 .98 .99 1.13 1.14 Pounds , S02/MM Btu 1.7 1.8 1.8 2.0 1.7 1.8 1.9 2.6 1.7 1.7 1.8 2.6 1.7 1.8 1.8 2.1 2.1 Sodium oxide performed only on 14 mesh x 0 sample ------- TABLE H. - Detailed washability analyses of sample No. 6 (Con.) STATE: Texas COUNTY: Freestone FORMATION: Lower Calvert GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 63.4 Float- 1.30 75.2 78.4 1.30 - 1.40 19.2 18.0 1.40 - 1.60 3.6 2.6 Sink - 1.60 2.0 1.0 Size fraction: 14 x 100 Weight percent: 36.6 Float- 1.30 39.7 42.8 1.30 - 1.40 50.1 50.4 1.40 - 1.60 6.7 5.1 Sink - 1.60 3.5 1.4 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 62.2 70.0 1.30 - 1.40 30.5 37.7 1.40 - 1.60 4.7 3.9 Sink - 1.60 2.6 1.2 Minus 100 mesh 9.8 8.6 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 56.3 60.6 1.30 - 1.40 31.6 31.8 1.40 - 1.60 8.1 6.4 Sink - 1.60 4.0 1.2 Btu/lb 11,429 10,301 8,069 5,391 11,777 11,035 8,337 4,478 11,510 10,742 8,208 4,938 10,437 11,769 10,984 8,604 3,235 Ash 8.8 16.3 32.3 47.9 7.6 11.6 28.3 52.4 8.5 13.5 30.2 50.1 16.5 8.2 12.9 28.2 63.3 Percent Pyritic sulfur 0.07 .16 .29 9.14 0.06 .10 .44 4.64 0.07 .12 .37 6.91 .30 0.08 .11 .33 8.93 Total sulfur N3201 0.92 .97 .96 9.52 0.95 .95 1.01 5.15 0.93 .96 .99 7.36 1.20 0.94 0.03 .95 .03 1 . 06 .04 7.19 .06 Cumulative Percent Recovery, pet. Weight Btu 75.2 94.4 98.0 100.0 39.7 89.8 96.5 100.0 62.2 92.7 97.4 100.0 100.0 56.3 87,9 96.0 100.0 78.4 96.4 99.0 100.0 42.8 93.5 98.6 100.0 70.0 95.3 98.8 100.0 100.0 60.6 92.4 98.8 100.0 Btu/lb 11,429 11,200 11,086 10,970 11,777 11,363 11,152 10,922 11,510 11,257 11,109 10,952 10,905 11,769 11,487 11,242 10,923 Ash 8.8 10.3 11.1 11.9 7.6 9.8 11.1 12.5 8.5 10.1 11.1 12.1 12.5 8.2 9.9 11.4 13.5 Pyritic sulfur 0.07 .09 .10 .28 0.06 .08 .11 .26 0.07 .09 .10 .27 .28 0.08 .09 .11 .46 Total sulfur Na20 0.92 .93 .93 1.11 0.95 .95 .95 1.10 .93 .94 .94 1.10 1.11 0.94 0.03 .94 .03 .95 .03 1.20 .03 Pounds, S02/MM Btu 1.6 1.7 1.7 2.0 1.6 1.7 1.7 2.0 1.6 1.7 1.7 2.0 2.0 1.6 1.6 1.7 2.2 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 12. - Detailed washability analyses of sample No. 7 STATE: Texas COUNTY: Harrison FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 79.2 Float- 1.30 98.8 99.1 1.30 - l.AO .9 .8 1.40 - 1.60 .2 .1 Sink - 1.60 .1 .0 Size fraction: 3/8 x 14 Weight percent: 17.2 Float- 1.30 95.2 96.4 1.30 - 1.40 3.1 2.7 1.40 - 1.60 1.0 .7 Sink - 1.60 .7 .2 Size fraction: 14 x 100 Weight percent: 3.5 Float- 1.30 56.2 58.4 1.30 - 1.40 32.6 32.9 1.40 - 1.60 8.4 7.7 Sink - 1.60 2.8 1.0 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 96.7 97.8 1.30 - 1.40 2.4 16.6 1.40 - 1.60 .6 3.9 Sink - 1.60 .3 .4 Minus 100 mesh 1.0 .9 Btu/lb 11,320 9,631 7,750 3,250 11,246 9,897 7,540 2,450 11,294 10,949 9,969 3,780 11,306 10,320 8,755 3,110 10,225 Ash 9.2 21.9 34.5 66.3 8.7 18.7 36.0 72.0 8.2 10.4 15.4 62.6 9.1 15.7 25.8 67.3 16.6 Percent Pyritic sulfur 0.06 .17 .28 .66 0.04 .22 .51 2.88 0.03 .09 .20 2.39 0.06 .14 .30 2.09 .19 Total sulfur N3201 0.77 .80 .66 .95 0.83 .83 .92 2.93 0.81 .78 .83 2.47 0.78 .80 .81 2.22 .86 Cumulative Percent Recovery Weight 98.8 99.7 99.9 100.0 95.2 98.3 99.3 100.0 56.2 88.7 97.1 100.0 96.7 99.1 99.7 100.0 100.0 . pet. Btu 99.1 99.8 100.0 100.0 96.4 99.2 99.8 100.0 58.4 91.3 99.0 100.0 97.8 99.5 99.9 100.0 100.0 Btu/lb 11,320 11,305 11,298 11,289 11,246 11,204 11,167 11,105 11,294 11,167 11,064 10,853 11,306 11,282 11,267 11,241 11,231 Ash 9.2 9.3 9.4 9.4 8.7 9.0 9.3 9.7 8.2 9.0 9.6 11.1 9.1 9.3 9.4 9.5 9.6 Pyritic sulfur 0.06 .06 .06 .06 0.04 .05 .05 .07 0.03 .05 .06 .13 0.06 .06 .06 .07 .07 Total sulfur N3201 0.77 .77 .77 .77 0.83 .83 .83 .85 0.81 .80 .80 .85 0.78 .78 .78 .79 .79 Pounds, S02/MM Btu 1.4 1.4 1.4 1.4 1.5 1.5 1.5 1.5 1.4 1.4 1.4 1.6 1.4 1.4 1.4 1.4 1.4 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 12. - Detailed washability analyses of sample No. 7 (Con.) STATE: Texas COUNTY: Harrison FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 64.9 Float- 1.30 95.9 96.6 1.30 - 1.40 3.1 2.8 1.40-1.60 .7 .5 Sink - 1.60 .3 .1 Size fraction: 14 x 100 Weight percent: 35.1 Float- 1.30 68.5 69.9 1.30 - 1.40 26.1 25.8 1.40 - 1.60 4.4 3.8 Sink - 1.60 .9 .5 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 86.3 89.1 1.30 - 1.40 11.2 21.7 1.40 - 1.60 2.0 3.0 Sink - 1.60 .5 .3 Minus 100 mesh 11.0 9.8 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 80.7 81.7 1.30 - 1.40 17.1 16.7 1.40 - 1.60 1.9 1.5 Sink - 1.60 .4 .1 Sodium oxide performed only on Btu/lb 11,291 10,174 7,660 3,160 11,415 11,040 9,690 5,330 11,325 10,883 9,208 4,589 11,047 11,523 11,105 9,183 2,972 14 mesh Ash 8.6 17.1 35.1 67.0 8.0 10.0 18.0 50.6 8.4 11.8 22.1 56.2 11.7 7.7 10.6 24.4 72.1 Percent Pyritic sulfur 0.06 .20 .61 3.93 0.03 .06 .15 1.57 0.05 .09 .26 2.38 .10 0.04 .09 .44 3.08 Total sulfur N3201 0.82 .84 1.14 3.96 0.78 .82 .80 1.94 0.81 .82 .88 2.63 .82 0.80 0.11 .73 .11 .84 .09 3.10 .09 Cumulative Percent Recovery, pet. Weight 95.9 99.0 99.7 100.0 68.5 94.7 99.1 100.0 86.3 97.5 99.5 100.0 100.0 80.7 97.7 99.6 100.0 Btu 96.6 99.4 99.9 100.0 69.9 95.7 99.5 100.0 89.1 98.2 99.8 100.0 100.0 81.7 98.4 99.9 100.0 x 0 sample. Btu/lb 11,291 11,256 11,229 11,208 11,415 11,311 11,239 11,184 11,325 11,274 11,232 11,199 11,184 11,523 11,450 11,407 11,374 Ash 8.6 8.9 9.1 9.2 8.0 8.7 9.1 9.5 8.4 8.8 9.1 9.3 9.6 7.7 8.2 8.5 8.8 Pyritic sulfur 0.06 .06 .07 .08 0.03 .04 .04 .06 0.05 .06 .06 .07 .07 0.04 .05 .06 .07 Total sulfur N3201 0.82 .82 .82 .83 0.78 .79 .79 .80 0.81 .81 .81 .82 .82 0.80 0.11 .79 .11 .79 .11 .80 .11 Pounds, S02/MM Btu 1.5 1.5 1.5 1.5 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.5 1.5 1.4 1.4 1.4 1.4 ------- Channel sample No. 8 was collected from the Lower Calvert forma- tion, Wilcox Group, in Milam County, Texas. A section of the bed is described as follows: Bed Section1 Feet 3 4 4 Inches 3 7 1 1 0 Lignite Shale Lignite Shale Lignite Total thickness of bed 12 0 and sample 10verlying bed: shale; floor: fireclay. Table 13 shows the detailed washability analyses of sample No. 8. The composite washability sample contained an average of 9,948 Btu/lb, 19.8 percent ash, 0.15 percent pyritic sulfur, and 1.31 percent total sulfur. The sodium oxide content in the coal was 0.04 percent. This coal could not be upgraded to meet the current SC-2 emission standard of 1.2 pounds S02/MM Btu since it contained an average of 1.16 percent organic sulfur. Crushing to 3/8 inch top size and removing the sink 1.40 specific gravity material of the composite sample would provide a product analyzing 11.5 percent ash at a Btu recovery of 90.1 percent. The ash reduction would be 42 percent. None of this coal is washed. Channel sample No. 9 was collected from an uncorrelated formation, Wilcox Group, in Panola County, Texas. A section of the bed is de- scribed as follows: Bed Section1 Feet Inches Lignite 7 7 Total thickness of bed 7 7 and sample 10verlying bed: shale, floor; fireclay. Table 14 shows the detailed washability analyses of sample No. 9. The composite washability sample contained an average of 11,200 Btu/lb, 8.6 percent ash, 0.26 percent pyritic sulfur, and 1.32 percent total sulfur. The sodium oxide content of the coal was 0.08 percent. This sample contained an average of 1.06 percent organic sulfur and could not be upgraded to meet the current SC>2 emission standard. Crushing to 3/8 34 ------- TABLE 13. - Detailed washabllity analyses of sample No. 8 STATE: Texas COUNTY: Milam FORMATION: Lower Calvert GROUP: Wilcox Direct Recovery^ Product Weight pet . Btu Btu/lb Percent Pyritic Ash sulfur Total sulfur Na20] TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 78.5 Float- 1.30 79.8 1.30 - 1.40 10.2 1.40 - 1.60 3.7 Sink - 1.60 6.3 Size fraction: 3/8 x Weight percent: 17.7 Float- 1.30 64.6 1.30 - 1.40 13.9 1.40 - 1.60 6.4 Sink - 1.60 15.1 Size fraction: 14 x Weight percent: 3.8 Float- 1.30 45.5 1.30 - 1.40 17.8 1.40 - 1.60 14.4 Sink - 1.60 22.2 Size composite: 1-1/2 Weight percent: 100.0 Float- 1.30 75.9 1.30 - 1.40 11.1 1.40-1.60 '>.(, Sink - 1.60 8.4 Minus 100 mesh 1.1 86.6 9.3 2.6 1.6 14 76.9 14.3 5.2 3.6 100 58.0 21.3 13.9 6.8 x 100 84.5 11.1 4.6 2.7 1.2 11,130 9,32] 7,114 2,561 10,959 9,514 7,437 2,215 11,753 11,042 8,876 2,828 11,118 9,467 7,403 2,477 10,979 11.6 24.6 40.6 70.9 11.8 22.7 37.7 74.3 8.6 12.0 26.7 69.9 11.6 23.4 38.2 71.9 22.7 0.04 .31 .25 .78 0.06 .15 .18 1.20 0.04 .07 .16 .92 0.04 .26 .22 .93 .16 1.36 1.61 1.06 1.20 Cumulative Percent Recovery, pet. Weight Btu 79.8 90.0 93.7 100.0 I 1.44 1.36 1.07 1.73 1.31 1.37 1.26 1.25 1.37 1.54 1.09 1.37 .94 64.6 78.5 84.9 100.0 45.5 63.3 77.8 100.0 75.9 87.0 91.6 100.0 100.0 86.6 95.9 98.4 100.0 76.9 91.2 96.4 100.0 58.0 79.3 93.2 100.0 84.5 94.7 97.9 100.0 100.0 Btu/lb 11,130 10,925 10,775 10,261 10,959 10,764 10,458 9,210 11,753 11,554 11,056 9,226 11,118 10,907 10,731 10,035 10,045 Ash 11.6 13.1 14.2 17.7 11.8 13.7 15.5 24.4 8.6 9.6 12.7 25.5 11.6 13.1 14.3 19.2 19.2 Pyritic sulfur 0.04 .07 .08 .12 0.06 .08 .08 .25 0.04 .05 .07 .26 0.04 .07 .08 .15 .15 Total Pounds, sulfur N3201 S02/MM Btu 1.36 1.39 1.38 1.36 1.44 1.43 1.40 1.45 1.31 1.33 1.31 1.30 1.37 1.39 1.38 1.38 1.37 2.4 2.5 2.6 2.7 2.6 2.7 2.7 3.1 2.2 2.3 2.4 2.8 2.5 2.6 2.6 2.8 2.7 'Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 13. - Detailed washability analyses of sample No. 8 (Con.) STATE : Texas COUNTY: Milam FORMATION: GROUP: Direct Percent Recovery , pet . Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 70.2 Float- 1.30 69.0 78.0 1.30 - 1.40 15.0 14.7 1.40 - 1.60 6.8 5.1 Sink - 1.60 9.1 2.2 Size fraction: 14 x 100 Weight percent: 29.8 Float- 1.30 40.6 48.0 1.30 - 1.40 31.4 34.9 1.40 - 1.60 14.8 13.0 Sink - 1.60 13.2 4.1 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 60.6 72.0 1.30 - 1.40 19.9 24.2 1.40 - 1.60 9.2 8.9 Sink - 1.60 10.3 2.9 Minus 100 mesh 9.2 8.1 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 56.1 65.0 1.30 - 1.40 23.4 24.5 1.40 - 1.60 9.9 8.1 Sink - 1.60 10.7 2.5 Btu/lb 11,299 9,796 7,481 2,367 11,700 11,008 8,662 3,070 11,379 10,365 8,047 2,633 9,580 11,434 10,304 8,064 2,318 Ash 10.0 21.0 37.3 72.7 8.3 12.3 27.8 67.5 9.7 16.9 32.7 70.7 24.4 9.6 17.3 32.6 71.9 Pyritic sulfur 0.04 .17 .13 1.49 0.02 .05 .14 .62 0.04 .11 .13 1.16 .16 0.03 .09 .14 .75 Total sulfur N3201 1. 1. 1. 1. 1. 1. 1. • 1. 1. 1. 1. 1. 1. 1. 1. 33 46 07 72 32 33 20 97 33 40 13 44 20 30 0.03 29 .03 11 .04 97 .09 Lower Wilcox Calvert Cumulative Percent Recovery Weight 69.0 84.1 90.9 100.0 40.6 72.0 86.8 100.0 60.6 80.5 89.7 100.0 100.0 56.1 79.5 89.3 100.0 . pet. Btu 78.0 92.7 97.8 100.0 48.0 83.0 95.9 100.0 72.0 90.1 97.3 100.0 100.0 65.0 89.4 97.5 100.0 Btu/lb 11,299 11,030 10,764 9,998 11,700 11,398 10,932 9,896 11,379 11,128 10,812 9,967 9,935 11,434 11,101 10,766 9,865 Ash 10.0 12.0 13.9 19.2 8.3 10.0 13.1 20.2 9.7 11.5 13.6 19.5 19.9 9.6 11.9 14.2 20.3 Pyritic sulfur 0.04 .06 .07 .20 0.02 .03 .05 .13 0.04 .06 .06 .18 .18 0.03 .05 .06 .13 Total sulfur N3201 1.33 1.35 1.33 1.37 1.32 1.32 1.30 1.26 1.33 1.35 1.32 1.34 1.32 1.30 0.03 1.30 .03 1.28 .03 1.24 .04 Pounds, S02/MM Btu 2.4 2.5 2.5 2.7 2.3 2.3 2.4 2.5 2.3 2.4 2.4 2.7 2.7 2. 3 2.3 2.4 2.5 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 14. - Detailed washability analyses of sample No. 9 STATE: Texas COUNTY: Panola FORMATION: Uncorrelated GROUP: Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 79.3 Float- 1.30 97.0 97.5 1.30 - 1.40 2.5 2.1 1.40 - 1.60 .4 .3 Sink - 1.60 .2 .0 Size fraction: 3/8 x 14 Weight percent: 16.5 Float- 1.30 89.9 92.3 1.30 - 1.40 5.8 5.4 1.40 - 1.60 2.3 1.7 Sink - 1.60 2.0 .5 Size fraction: 14 x 100 Weight percent: 4.2 Float- 1.30 55.4 59.1 1.30 - 1.40 30.3 31.3 1.40 - 1.60 7.9 7.1 Sink - 1.60 6.4 2.5 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 94.1 95.8 1.30 - 1.40 4.2 11.7 1.40 - 1.60 1.0 3.1 Sink - 1.60 .7 1.1 Minus 100 mesh 1.2 1.0 Btu/lb 11,334 9,829 8,974 2,216 11,310 10,290 8,447 2,830 11,708 11,325 9,868 4,294 11,339 10,388 9,073 3,226 9,856 Ash 6.9 20.3 26.2 77.8 8.4 16.0 29.1 66.1 6.0 8.0 15.6 56.5 7.1 15.6 23.8 65.0 20.1 Percent Pyritic sulfur 0.09 .86 1.82 2.63 0.16 .55 1.26 17.70 0.05 .07 .26 11.43 0.10 .55 1.09 12.47 .49 Total sulfur N3201 1.30 2.90 2.78 2.97 1.08 1.42 1.99 17.71 1.03 .99 1.04 11.68 1.26 1.98 1.91 12.63 1.51 Cumulative Percent Recovery, pet. Weight Btu 97.0 99.4 99.8 100.0 89.9 95.7 98.0 100.0 55.4 85.7 93.6 100.0 94.1 98.3 99.3 100.0 100.0 97.5 99.7 100.0 100.0 92.3 97.7 99.5 100.0 59.1 90.4 97.5 100.0 95.8 99.0 99.8 100.0 100.0 Btu/lb 11,334 11,297 11,288 11,271 11,310 11,248 11,184 11,014 11,708 11,573 11,428 10,975 11,339 11,299 11,276 11,216 11,200 Ash 6.9 7.2 7.3 7. it 8.4 8.9 9.3 10.5 6.0 6.7 7.5 10.6 7.1 7.5 7.6 8.1 8.2 Pyritic sulfur 0.09 .11 .12 .12 0.16 .18 .21 .56 0.05 .06 .07 .80 0.10 .12 .13 .22 .22 Total sulfur fta20l 1.30 1.34 1.34 1.35 1.08 1.10 1.12 1.46 1.03 1.02 1.02 1.70 1.26 1.29 1.30 1.38 1.38 Pounds, S02/MM Btu 2.3 2.4 2.4 2.4 1.9 2.0 2.0 2.6 1.8 1.8 1.8 3.1 2.2 2.3 2.3 2.5 2.5 1Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 14. - Detailed washability analyses of sample No. 9 (Con.) STATE: Texas COUNTY: Panola FORMATION: Uncorrelated GROUP: Wilcox Direct Percent Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 68.5 Float- 1.30 92.2 93.6 1.30 - 1.40 4.9 4.6 1.40 - 1.60 2.0 1.6 Sink - 1.60 .9 .3 Size fraction: 14 x 100 Weight percent: 31.8 Float- 1.30 70.3 72.9 1.30 - 1.40 20.3 20.2 1.40 - 1.60 6.6 5.8 Sink - 1.60 2.8 1.0 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 85.3 88.3 1.30 - 1.40 9.8 14.8 1.40 - 1.60 3.4 4.2 Sink - 1.60 1.5 .7 Minus 100 mesh 10.1 8.7 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 77.0 78.7 1.30 - 1.40 19.6 19.3 1.40 - 1.60 2.0 1.6 Sink - 1.60 1.5 .4 Btu/lb 11,448 10,383 8,986 3,184 11,647 11,175 9,906 4,022 11,499 10,900 9,542 3,677 10,654 11,449 11,051 9,264 2,829 Ash 6.9 16.0 25.8 64.9 6.2 9.2 16.3 58.6 6.7 11.6 20.0 61.2 13.7 6.5 10.6 23.5 68.6 Pyritic sulfur 0.07 .31 .72 19.20 0.04 .09 .24 9.29 0.06 .17 .43 13.36 .29 0.06 .12 .49 13.73 Total sulfur N3201 1. 1. 1. 19. 1. . . 9. 1. 1. 1. 13. 1. 1. 1. 1. 14. 09 16 46 20 04 98 99 34 08 04 18 39 77 03 0.07 19 .10 07 .08 93 .06 Cumulative Percent Recovery Weight 92.2 97.1 99.1 100.0 70.3 90.6 97.2 100.0 85.3 95.0 98.5 100.0 100.0 77.0 96.6 98.5 100.0 , pet. Btu 93.5 98.2 99.7 100.0 72.9 93.2 99.0 100.0 88.3 96.7 99.5 100.0 100.0 78.7 98.0 99.6 100.0 Btu/lb 11,448 11,394 11,346 11,271 11,647 11,541 11,430 11,219 11,499 11,438 11,371 11,255 11,199 11,449 11,368 11,326 11,202 Ash 6.9 7.4 7.7 8.3 6.2 6.9 7.5 9.0 6.7 7.2 7.7 8.5 9.0 6.5 7.3 7.7 8.5 Pyritic sulfur 0.07 .08 .09 .27 0.04 .05 .06 .33 0.06 .07 .09 .29 .29 0.06 .07 .08 .28 Total sulfur 1.09 1.09 1.10 1.27 1.04 1.03 1.02 1.26 1.08 1.07 1.08 1.26 1.31 1.03 1.06 1.06 1.27 Pounds, N3201 S02/MM Btu 1.9 1.9 1.9 2.2 1.8 1.8 1.8 2.2 1.9 1.9 1.9 2.2 2.3 0.07 1.8 .08 1.9 .08 1.9 .08 2.3 1Sodium oxide performed only on 14 mesh x 0 sample. ------- inch top size and removing the sink 1.30 specific gravity material would provide a product analyzing 6.7 percent ash at a Btu recovery of 88.3 percent. The ash reduction would be 26 percent. None of this coal is washed. Channel sample No. 10 was collected from an uncorrelated formation, Wilcox Group, in Titus County, Texas. A section of the bed is described as follows: Bed Section1 Lignite Carbonaceous shale Lignite Carbonaceous shale Lignite Total thickness of bed Feet 1 1 1 7 Inches 0 6 4 3 11 0 and sample 10verlying bed: shale; floor: fireclay. Table 15 shows the detailed washability analyses of sample No. 10. The composite washability sample contained an average of 10,122 Btu/lb, 17.0 percent ash, 0.10 percent pyritic sulfur, and 0.83 percent total sulfur. The sodium oxide content in the coal was 0.09 percent. This sample contained an average of 0.73 percent organic sulfur and could not be upgraded to meet the current SO? emission standard. Crushing to 3/8 inch top size and removing the sink 1.40 specific gravity material would provide a product analyzing 12.2 percent ash, at a Btu recovery of 91.8 percent. The ash reduction would be 29 percent. None of this coal is washed. Channel sample No. 11 was collected from a Yegua formation, Clair- borne Group, in Angelina County, Texas. A section of the bed is de- scribed as follows: Bed Section1 Feet Lignite Inches 0 0 Total thickness of bed 4 and sample Overlying bed: shale; floor: sandstone. Table 16 shows the detailed washability analyses of sample No. 11. The composite washability sample contained an average of 10,590 Btu/lb, 39 ------- TABLE 15. - Detailed washability analyses of sample No. 10 STATE : Texas COUNTY: Titus FORMATION: Uncorrelated GROUP : Wilcox Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 78.9 Float- 1.30 80.0 84.0 1.30 - 1.40 12.2 11.4 1.40 - 1.60 5.0 3.6 Sink - 1.60 2.8 .9 Size fraction: 3/8 x 14 Weight percent: 17.5 Float- 1.30 70.4 76.8 1.30 - 1.40 16.3 15.8 1.40 - 1.60 7.3 5.6 Sink - 1.60 6.0 1.9 Size fraction: 14 x 100 Weight percent: 3.6 Float- 1.30 28.0 33.0 1.30 - 1.40 38.0 42.3 1.40 - 1.60 20.1 19.1 Sink - 1.60 14.0 5.6 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 76.4 82.2 1.30 - 1.40 13.9 15.3 1.40 - 1.60 5.9 6.0 Sink - 1.60 3.8 1.8 Minus 100 mesh .9 .7 Btu/lb 10,686 9,468 7,469 3,398 10,759 9,567 7,499 3,079 11,273 10,669 9,067 3,839 10,705 9,607 7,671 3,368 7,775 Ash 12.7 22.9 37.7 66.6 11.7 20.8 36.4 69.9 9.3 12.2 22.9 63.5 12.5 21.4 35.6 67.1 36.1 Percent Pyritic sulfur 0.07 .13 .48 .24 0.03 .13 .48 .94 0.02 .04 .17 1.77 0.06 .12 .44 .64 .27 Total sulfur N3201 0.84 .84 1.05 .55 0.85 .86 1.13 1.14 0.85 .80 .82 2.16 0.84 .84 1.04 .93 .88 Cumulative Percent Recovery Weight 80.0 92.2 97.2 100.0 70.4 86.7 94.0 100.0 28.0 65.9 86.0 100.0 76.4 90.3 96.2 100.0 100.0 . pet. Btu 84.0 95.4 99.1 100.0 76.8 92.6 98.1 100.0 33.0 75.3 94.4 100.0 82.2 94.4 98.8 100.0 100.0 Btu/lb 10,686 10,524 10,369 10,172 10,759 10,536 10,298 9,868 11,273 10,925 10,491 9,562 10,705 10,536 10,360 10,096 10,076 Ash 12.7 14.1 15.3 16.7 11.7 13.4 15.2 18.5 9.3 11.0 13.8 20.7 12.5 13.9 15.2 17.2 17.3 Pyritic sulfur 0.07 .08 .10 .10 0.03 .05 .08 .13 0.02 .03 .06 .30 0.06 .07 .09 .12 .12 Total sulfur N3201 0.84 .84 .85 .84 0.85 .85 .87 .89 0.85 .82 .82 1.01 0.84 .84 .85 .86 .86 Pounds, S02/MM Btu 1.6 1.6 1.6 1.7 1.6 1.6 1.7 1.8 1.5 1.5 1.6 2.1 1.6 1.6 1.6 1.7 1.7 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 15. - Detailed vashability analyses of sample No. 10 (Con.) STATE: Texas COUNTY: Titus FORMATION: GROUP: Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 66.7 Float- 1.30 75.0 80.1 1.30 - 1.40 14.2 13.5 1.40 - 1.60 6.6 5.0 Sink - 1.60 4.2 1.3 Size fraction: 14 x 100 Weight percent: 33.3 Float- 1.30 52.7 58.0 1.30 - 1.40 29.6 30.1 1.40 - 1.60 11.6 9.6 Sink - 1.60 6.0 2.3 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 67.6 74.4 1.30 - 1.40 19.3 22.0 1.40 - 1.60 8.3 7.2 Sink - 1.60 4.8 1.7 Minus 100 mesh 8.7 7.0 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 55.2 60.3 1.30 - 1.40 27.1 27.2 1.40 - 1.60 13.7 11.3 Sink - 1.60 3.9 1.2 Btu/lb 10,850 9,684 7,766 3,227 11,332 10,462 8,497 3,927 10,975 10,081 8,107 3,519 8,872 11,116 10,242 8,404 3,124 Ash 11.3 20.1 34.4 67.8 9.6 14.3 27.1. 63.4 10.9 17.1 31.0 66.0 27.7 9.8 16.2 28.0 69.2 Percent Pyritic sulfur 0.00 .06 .66 .25 0.14 .29 .10 1.30 0.04 .18 .40 .69 .08 0.01 .02 .05 1.12 Total sulfur N3201 0.80 .75 .82 .98 0.85 .85 .78 1.64 0.81 .80 .80 1.26 .81 0.81 0.09 .74 .09 .67 .08 1.42 .12 Uncorrelated Wilcox Cumulative Percent Recovery, pet. Weight Btu 75.0 89.2 95.8 100.0 52.7 82.4 94.0 100.0 67.6 86.9 95.2 100.0 100.0 55.2 82.3 96.1 100.0 80.1 93.6 98.7 100.0 58.0 88.1 97.7 100.0 74.4 91.9 98.3 100.0 100.0 60.3 87.5 98.8 100.0 Btu/lb 10,850 10,665 10,465 10,162 11,332 11,019 10,708 10,298 10,975 10,776 10,544 10,207 10,100 11,116 10,829 10,482 10,191 Ash 11.3 12.7 14.2 16.4 9.6 11.3 13.2 16.3 10.9 12.3 13.9 16.4 17.3 9.8 11.9 14.2 16.4 Pyritic sulfur 0.00 .01 .05 .06 0.14 .19 .18 .25 0.04 .07 .10 .12 .12 0.01 .01 .02 .06 Total sulfur N3201 0.80 .79 .79 .80 0.85 .85 .84 .89 0.81 .81 .81 .83 .83 0.81 0.09 .79 .09 .77 .09 .80 .09 Pounds, S02/MM Btu 1.5 1.5 1.5 1.6 1.5 1.5 1.6 1.7 1.5 1.5 1.5 1.6 1.6 1.5 1.5 1.5 1.6 'Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 16. - Detailed washability analyses of sample No. 11 STATE: Texas COUNTY: Angelina FORMATION: Yegua GROUP: Clairborne Direct Recovery, pet. Product Weight Btu TOP SIZE: 1-1/2 Size fraction: 1-1/2 x 3/8 Weight percent: 80.8 Float- 1.30 92.2 94.4 1.30 - 1.40 5.6 4.9 1.40 - 1.60 .6 .3 Sink - 1.60 1.6 .4 Size fraction: 3/8 x 14 Weight percent: 14.9 Float- 1.30 80.0 87.8 1.30 - 1.40 9.1 8.0 1.40 - 1.60 5.1 3.1 Sink - 1.60 5.8 1.2 Size fraction: 14 x 100 Weight percent: 4.3 Float- 1.30 50.0 64.9 1.30 - 1.40 16.4 17.8 1.40 - 1.60 13.1 10.6 Sink - 1.60 20.5 6.6 Size composite: 1-1/2 x 100 Weight percent: 100.0 Float- 1.30 88.6 92.8 1.30 - 1.40 6.6 6.9 1.40 - 1.60 1.8 4.7 Sink - 1.60 3.0 2.4 Minus 100 mesh 1.1 .9 Btu/lb 11,073 9,468 5,436 2,780 10,852 8,610 5,873 2,019 11,187 9,385 6,985 2,780 11,046 9,281 6,105 2,564 8,161 Ash 10.9 21.9 51.4 72.6 12.2 27.8 46.8 75.8 10.3 20.7 36.5 69.6 11.1 23.0 44.8 72.6 35.7 Percent Pyritic sulfur 0.04 .09 .36 2.10 0.04 .11 .14 .78 0.04 .07 .10 .36 0.04 .09 .19 1.22 .26 Total sulfur Ua20l 1.20 1.29 1.03 2.16 1.27 1.42 1.07 1.07 1.23 1.47 1.14 .99 1.21 1.34 1.08 1.51 1.31 Cumulative Percent Recovery Weight 92.2 97.8 98.4 100.0 80.0 89.1 94.2 100.0 50.9 66.4 79.5 100.0 88.6 95.2 97.0 100.0 100.0 » pet. Btu 94.4 99.3 99.6 100.0 87.8 95.8 98.8 100.0 64.9 82.8 93.4 100.0 92.8 98.3 99.3 100.0 100.0 Btu/lb 11,073 10,982 10,949 10,818 10,852 10,622 10,363 9,882 11,187 10,742 10,122 8,618 11,046 10,924 10,834 10,583 10,556 Ash 10.9 11.5 11.8 12.7 12.2 13.8 15.6 19.1 10.3 12.9 16.8 27.6 11.1 11.9 12.5 14.3 14.6 Pyritic sulfur 0.04 .04 .04 .08 0.04 .05 .05 .09 0.04 .05 .06 .12 0.04 .04 .05 .08 .08 Total sulfur N3201 1.20 1.21 1.20 1.22 1.27 1.29 1.27 1.26 1.23 1.29 1.26 1.21 1.21 1.22 1.22 1.23 1.23 Pounds, S02/MM Btu 2.2 2.2 2.2 2.3 2.3 2.4 2.5 2.6 2.2 2.4 2.5 2.8 2.2 2.2 2.2 2.3 2.3 Sodium oxide performed only on 14 mesh x 0 sample. ------- TABLE 16. - Detailed washability analyses of sample No. 11 (Con.) STATE: Texas COUNTY: Angelina FORMATION: Yegua GROUP: Clairborne Direct Recovery, pet. Product Weight Btu TOP SIZE: 3/8 Size fraction: 3/8 x 14 Weight percent: 73.6 Float- 1.30 92.7 95.7 1.30 - 1.40 3.8 3.1 1.40 - 1.60 1.5 .8 Sink - 1.60 2.0 .4 Size fraction: 14 x 100 Weight percent: 26.4 Float- 1.30 80.8 87.6 1.30 - 1.40 4.8 4.6 1.40 - 1.60 6.8 5.4 Sink - 1.60 7.6 2.5 Size composite: 3/8 x 100 Weight percent: 100.0 Float- 1.30 89.5 93.8 1.30 - 1.40 4.1 3.5 1.40 - 1.60 2.9 3.7 Sink - 1.60 3.5 1.6 Minus 100 mesh 6.2 5.0 TOP SIZE: 14 Size fraction: 14 x 0 Weight percent: 100.0 Float- 1.30 85.5 91.2 1.30 - 1.40 7.0 6.2 1.40 - 1.60 3.7 2.1 Sink - 1.60 3.8 .6 1Sodium oxide performed only on Btu/lb 11,195 8,707 5,871 2,141 11,480 10,041 8,401 3,423 11,262 9,121 7,432 2,879 9,092 11,239 9,263 6,040 1,536 14 mesh Ash 10.0 28.4 46.6 75.3 9.4 17.2 26.7 64.4 9.9 24.9 34.3 69.0 25.5 10.0 23.6 46.4 81.5 Percent Pyritic sulfur 0.06 .14 .18 1.44 0.04 .07 .11 .42 0.06 .10 .14 .85 .12 0.05 .12 .12 .83 Total sulfur ^O1 1.33 1.26 1.02 1.66 1.21 1.32 1.24 1.11 1.30 1.28 1.16 1.34 1.20 1.29 0.25 1.27 .30 .83 .38 1.04 .58 Cumulative Percent Recovery, pet. Weight 92.7 96.5 98.0 100.0 80.8 85.6 92.4 100.0 89.5 93.6 96.5 100.0 100.0 85.5 92.5 96.2 100.0 Btu 95,7 98.8 99.6 100.0 87.6 92.1 97.5 100.0 93.8 97.2 99.1 100.0 100.0 91.2 97.3 99.4 100.0 Btu/lb 11,195 11,097 11,016 10,838 11,480 11,399 11,177 10,589 11,262 11,169 11,056 10,772 10,674 11,239 11,089 10,895 10,540 Ash 10.0 10.7 11.3 12.6 9.4 9.8 11.1 15.1 9.9 10.5 11.2 13.2 14.0 10.0 11.0 12.4 15.0 Pyritic sulfur 0.06 .06 .06 .09 0.04 .04 .05 .08 0.06 .06 .06 .09 .09 0.05 .06 .06 .09 Total sulfur 1.33 1.33 1.32 1.33 1.21 1.22 1.22 1.21 1.30 1.30 1.30 1.30 1.29 1.29 1.29 1.27 1.26 Pounds, Na20J S02/MM Btu 2.4 2.4 2.4 2.5 2.1 2.1 2.2 2.3 2.3 2.3 2.3 2.4 2.4 0.25 2.3 .25 2.3 .25 2.3 .27 2.4 x 0 sample. ------- 14.5 percent ash, 0.09 percent pyritic sulfur, and 1.26 percent total sulfur. The sodium oxide content in the coal was 0.27 percent. This coal contained an average of 1.17 percent organic sulfur and could not be upgraded to meet the current SQ2 emission standard. Crushing to 14 mesh top size and removing the sink 1.30 specific gravity material would provide a product containing 10.0 percent ash at a Btu recovery of 91.2 percent. The ash reduction would be 33 percent. This is a new mine undergoing a feasibility study. Sodium Reduction Table 17 summarizes the results of laboratory ion exchange tests with Arkansas and Texas lignites. In these tests, products having lower sodium oxide in the ash were consistently obtained by treating these lignites with a solution containing calcium ions. Because the quantity of exchange ions, particle size distribution and reaction time were constant; the maximum amount of sodium that might be removed from each sample was not determined. The sodium oxide reductions for the coals tested ranged from 37 to 91 percent. TABLE 17. - Ion exchange test results with minus 14 mesh Arkansas and Texas lignites Raw coal Analysis, percent Sample Na2^ in ash No. Ash Untreated Treated Float 1.60 specific gravity product Recovery, Analysis, percent percent Na20 in ash Btu's Ash UntreatedTreated Arkansas lignite 1 2 3 4 11.3 17.0 15.0 43.4 0.19 .19 .08 .27 0.11 .12 .04 .17 99.5 99.6 98.2 88.3 9.9 14.7 11.8 31.9 0.24 .27 .08 .39 0.09 .12 .05 .14 Texas lignite 5 6 7 8 9 10 11 10.2 13.5 8.8 20.3 8.5 16.4 15.0 0.98 .67 1.13 .24 1.06 .65 1.27 0.22 .14 .37 .14 .31 .19 .12 97.8 98.8 99.9 97.5 99.6 98.8 99.4 9.0 11.4 8.5 14.2 7.7 14.2 12.4 0.91 .54 1.09 .30 1.08 .73 1.05 0.25 .14 .35 .12 .25 .23 .12 44 ------- DISCUSSION OF RESULTS The washability data given in tables 6-9 for the lignite samples collected in Arkansas show that, of the four samples, only samples 1 and 2, from Dallas County, could be upgraded to meet the current EPA S02 emission standard of 1.2 pounds S02/MM Btu. Sample No. 1 contained an average of 0.47 percent pyritic sulfur and Q.46 percent organic sulfur. As shown in table 6, it could be upgraded to comply with the EPA emis- sion standard by crushing to 3/8-inch top size and removing the sink 1.30 specific gravity material. Sample No. 2 contained, on the average, 0.05 percent pyritic sulfur and only 0.65 percent organic sulfur. It could be upgraded to meet the standard by crushing to 1-1/2-inch top size and removing the sink 1.30 specific gravity material as shown in table 7. The washability data for the Texas lignites (tables 10-16) show that none of these samples could be upgraded to meet the EPA standard regardless of the degree of crushing or specific gravity of separation due to the organic sulfur content which ranged from 0.7 to 1.3 percent. Although physical cleaning generally provided inadequate desul- furization with all but the two Arkansas lignite samples from Dallas County, it did provide significant ash reduction. And as pointed out earlier, boiler fouling increases exponentially with the ash content of a coal for all levels of sodium oxide in the ash. Crushing and gravi- metric separation, therefore, may contribute significantly to a reduc- tion in boiler fouling. The weight-percent yields obtained at the 1.30 specific gravity of separation for the material crushed to 1-1/2 inches top size were high, except for one sample which yielded 42.8 percent. The other 10 samples ranged from 75.9 percent to 96.7 percent yield. This high yield of float 1.30 material is attributable to the low specific gravity of lignite. It is reported that the specific gravity of lignite containing 36 percent moisture is 1.28 and decreases to 1.22 as the moisture de- creases to zero (10). Size analysis of the Arkansas and Texas lignite samples showed that all samples remained relatively coarse after crushing to 1-1/2 inches top size with none containing less than 73 percent of 1-1/2 by 3/8 inch material. The size distribution coefficient 11 ranged from 0.7 to 0.8 which is within the normal range for most higher rank coals. All of these Arkansas and Texas lignite samples were noncoking with free swelling indices of 0. The ash softening temperatures ranged from 2,140 to 2,910° F. Generally, the Btu per pound (moisture free basis) for the raw lignite samples was around 10,000 to 11,500 with the ash contents ranging from 9.3 to 19.3 percent. One of the Arkansas samples, however, contained 43.1 percent ash and 6,672 Btu/lb. 45 ------- The sodium oxide in the lignites analyzed 0.27 percent or less and thus should not cause much boiler fouling. This low sqdium content appears to be typical of Arkansas and Texas lignites. Although boiler fouling caused by the presence of sodium should not be a problem, it is interesting to note that treatment of these lignite samples with calcium ions provided sodium oxide reductions ranging from 37 to 91 percent. The significance of these ion exchange tests is to demonstrate that treatment of lignite with a solution containing calcium ions will reduce its sodium content. CONCLUSIONS 1. Only the two Arkansas samples collected from Dallas County could be upgraded to meet the new source performance standard of 1.2 pounds of S02/MM Btu. 2. None of the samples collected from Texas could be upgraded to meet the EPA standard. 3. Even though the samples collected from Arkansas and Texas averaged only 1.1 percent total sulfur, approximately 80 percent of this was organic sulfur; thus, 9 of the 11 samples could not be physically upgraded to meet EPA's new source performance standard. 4. The size analyses of the Arkansas and Texas lignite samples showed nonfriability with all samples containing more than 73 percent of plus 3/8 inch material after crushing to 1-1/2 inches top size. 5. Except for one sample, crushing and gravimetric separation would provide minimal sulfur reduction but would provide significant ash reduction and increased calorific value. 6. The sodium oxide in the coals analyzed 0.27 percent or less and thus should not cause much boiler fouling. However, since the ash foul- ing rate is related to the quantity of ash as well as the sodium con- tent, physical coal cleaning to remove ash should reduce boiler fouling. 7. Treatment of these lignite samples with calcium ions would provide sodium oxide reductions ranging from 37 to 91 percent. REFERENCES 1. Corsentino, J. S. Projects to Expand Energy Sources in Western States, SBM I.e. 8719, 208 pp. 2. Fieldner, A. C. and W. A. Selvig. Notes in the Sampling and Analysis of Coal. BuMines Tech. Paper 586, 1938, 48 pp. 46 ------- 3. Hahn, A. D. and B. M. Reynolds. Hgnite in the Arkansas- White-Red River Basins, Preliminary Report 1952, 15 pp. 4. Haley, R. B. Coal Resources of Arkansas, 1954, Geological Survey Bulletin 1072-P, 36 pp, 5. Holmes, J. A. The Sampling of Coal in the Mine. BuMines Tech. Paper 1, 1918, 22 pp. 6. Kaiser, W. R. Texas Lignite: Near-Surface and Deep-Basin Resources, Bureau of Economic Geology, University of Texas, R.I. No. 79, 1974, 70 pp. 7. Keystone Coal Industry Manual, McGraw-Hill Publication, 1977. 8. Paulson, L. E. and W. W. Rawkes. Changes in Ash Composition of North Dakota Lignite Treated by Ion Exchange. BuMines, R.I. 7176, 1967, 18 pp. 9. Rosin, P., E. Rammler. The Laws Governing the Fineness of Powered Coal, J Inst Fuel, 7, (1933), pp 29-36. 10. Sondreal, E. A. and R. C. Ellman. Laboratory Determination of Factors Affecting Storage of North Dakota Lignite. BuMines R.I. 7887, 1974, 83 pp. 11. Stroud, R. B. Mineral Resources and Industries of Arkansas, BuMines Bull. 645, 418 pp. 12. Tufte, P. H., G. H. Gronhard, E. A. Sondreal, and S. J. Selle. Ash Fouling Potentials of Western Subbituminous Coals Determined in a Pilot-Plant Test Furnace, Proceedings American Power Conference, Vol. 38, 1976, pp. 661-671. US GOVERNMENT PRINTING OFFICE: 1980-640-25k, 1967 47 ------- TECHNICAL REPORT DATA (Please read Instructions on the reverse before completing) 1. REPORT NO. EPA-600/7-79-149 3. RECIPIENT'S ACCESSION-NO. .TITLE AND SUBTITLE Washability Characteristics of Arkansas and Texas Lignites: Report of Investigations 5. REPORT DATE June 1979 6. PERFORMING ORGANIZATION CODE 7. AUTHOR(S) J.A. Cavallaro and A.F. Baker 8. PERFORMING ORGANIZATION REPORT NO. PMTC-5(79) 9. PERFORMING ORGANIZATION NAME AND ADDRESS U.S. Department of Energy Coal Preparation Division of Pittsburgh Mining Technology Center Pittsburgh, Pennsylvania 15213 10. PROGRAM ELEMENT NO. E HE 62 3 A 11. CONTRACT/GRANT NO. E PA Inter agency Agreement IAG-DXE-685AK 12. SPONSORING AGENCY NAME AND ADDRESS EPA, Office of Research and Development Industrial Environmental Research Laboratory Research Triangle Park, NC 27711 13. TYPE OF REPORT AND PERIOD COVERED Final: 1/77 - 9/78 14. SPONSORING AGENCY CODE EPA/600/13 15. SUPPLEMENTARY NOTES T£RL_RTp project officer is David A. Kirchgessner, MD-61,919/ 541-2851. 16. ABSTRACT The report describes the washability characteristics of 11 channel samples of lignite: 4 from Arkansas and 7 from Texas. The two samples collected from Dallas County, Arkansas, could be upgraded to meet the current EPA New Source Performance Standard (NSPS) of 1.2 Ib SO2/million Btu. The other nine samples, although averaging only a little over 1% total sulfur, were relatively high in organic sulfur and could not be upgraded to meet the NSPS. Physically cleaning these samples provided significant ash reduction which may reduce the potential for boiler fouling. It was also shown that much of the sodium can be removed from these lignites. Analyses showed 37 to 91% reductions of sodium oxide after treatment with a solu- tion containing calcium ions. 17. KEY WORDS AND DOCUMENT ANALYSIS DESCRIPTORS b.lDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group Pollution Lignite Washing Desulfurization Ash Content Scale (Corrosion) Sodium Oxides Calcium Pollution Control Stationary Sources 13B 08G 13H,07A 07D 07B 18. DISTRIBUTION STATEMENT Release to Public 19. SECURITY CLASS (This Report) Unclassified 21. NO. OF PAGES 20. SECURITY CLASS (Thispage) Unclassified 22. PRICE EPA Form 2220-1 <»-73) ------- |