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This article examines the chemical fractionation (leaching) of elements from the Whitewood Mine subbituminous coals and coal ashes at 120 C, 750 C, and 1000 C. The elements Ba, Zn, and Mn are easily leached from coal by water, ammonium acetate, and hydrochloric acid. Potassium is highly extractable by NH4O acetate but very little with HCl. Hydrochloric acid leaches most of Fe, whereas very small quantities of the element are leached by water or NH4O acetate. Low extractability from coal was noted for Si, Ti, and Cu, an indication of their association with detrital minerals. Extractability of Na from coal was low, which indicates an association with minerals rather than being in the form of exchangeable ions. High leachability for Ca, Sr, and to a certain degree, Mn, Mg, and Na were noted for the 120 C ash samples. Zinc, Ba, S, and P showed a wide variation, reflecting a complex association with carbonate, sulphate, sulphide minerals, and organic matter. Silica, Al, B, Li, Cu, and Mo were completely insolu...

Determining thermal maturity studies in the Ellef Ringnes Island area was complicated by numerous factors, such as the presence of cavings, bitumen staining, and igneous intrusions. Cavings are a problem in certain intervals in Hoodoo H-37, Dome Bay P-36, and Helicopter J-12. Bitumen staining resulting in suppression of reflectance has occurred in the lower part of the Jameson Bay shales in Elve M-40. Thick sills resulted in increase of Ro to 4.0%, whereas thin sills had a minimal impact on reflectance increase. Other features observed include overpressuring caused by hydrocarbon generation in the Schei Point source rocks as well as in the Jameson and Ringnes shales, and a “kinky” Ro profile caused by the presence of low-permeability gas-bearing reservoirs in the Heiberg sandstones in Jackson Bay G-16A. The presence of sapropelic coals with HI up to 329 mg HC/gTOC in Heiberg sandstones in Elve M-40 containing Botryococcus algae should also be noted. Calculated maturation gradients vary from 0.95 ...

The hydrocarbon potential of the Mesozoic succession in the vicinity of King Christian Island in central Sverdrup Basin was evaluated on the basis of maturation parameters and knowledge of the regional geology. The Triassic Schei Point Group, which is the main source rock interval in Sverdrup Basin, is in the mature stage of hydrocarbon generation (Ro>0.60%). The type of organic matter is mainly plank-tonic marine algae and bituminite, deposited in an offshore shelf setting. Rock-Eval Tmax values are in the range 428–444°Q in general agreement with reflectance. Organic richness is indicated by the high hydrogen index (HI) values in the shales (in excess of 300 mg HC/gTOC). Less rich source rocks are found in the Jurassic-age Jameson Bay and Ringnes formations, in accordance with previous studies in the nearby Lougheed and Melville islands. Numerous oil and gas fields have been discovered in King Christian Island to date. Geology shows that the presence or absence of liquid and gaseous hydrocarbon...

Coals and associated carbonaceous strata along the Red Deer River Valley in Alberta have a wide variation in boron concentrations (10--628 ppm). Boron concentrations decrease from bottom to top of the coal-bearing succession, closely reflecting changes in depositional environment conditions. These changes range from subaquatic deposition in the delta plain area and influence of brackish waters due to a marine transgression, to deposition in areas removed from any brackish water influence. There is good agreement between boron variation and depositional environment as interpreted from regional geology. However, the relation between boron and sulfur is not clear; samples with high boron concentrations are high in sulfur while low boron samples also have high sulfur. Compared to mean concentrations in world coals, some of the highest elemental concentrations measured in coals of this study are: As (38.0 ppm), Ba (2800 ppm), Cr (91.0 ppm), Mn (232 ppm), and V (209 ppm). There is a similarity in the vertical variation of the elements Th and Hf, while bentonite layers are enriched in Ba and Sr, pointing to the presence of gorceixite. No enrichment of REEs was observed in the bentonite layers. A comparison of elemental concentration to world mean values for coals showsmore » that the RDRV coals are elevated in As (up to 4{times}), Cr (up to 12 {times}), Mn (up to 4 {times}), Mo (up to 12 {times}), Th (up to 5 {times}), V (up to 12 {times}) and Zn (up to 5 {times}). Compared to coals from the eastern Alberta Plains of similar rank, age, and depositional environment, the RDRV coals have higher or similar concentrations of all elements of environmental significance, with the exception of Be and Pb. When compared to coals of similar rank in the western Alberta plains deposited under freshwater conditions, the RDRV coals have higher concentration of As, B, Ba, Sb, and Sr, similar concentrations of Be, Co, Cu, Mn, Pb, Se, Th, and U, and lower concentrations of Ni.« less

Concentrations of the elements As, B, Br, Cl, Cr, Mn, Na, Sb, Th, U, V, and Zn were determined in ply-by-ply samples from two sections of subbituminous coal from seam 3, Vesta Mine, Alberta Plains. The elemental mean concentrations in section 1 were As l.0 ppm, B 215ppm, Br 2.3ppm, Cl 29ppm, Cr 7.4ppm, Co 1.1 ppm, Mn 24.5 ppm, Mo 2.5 ppm, Na 4900ppm, Sb 0.4 ppm, Se 0.8 ppm, Ti 270 ppm, U 1.4 ppm, Th 2.8 ppm, V 2.9 ppm, and Zn 9.5 ppm. In section 2, the mean concentrations were As 0.7 ppm, B 201 ppm, Br 1.6 ppm, CI 24 ppm, Cr20ppm, Co 1.7 ppm, Mn 30.0ppm, Mo 2.8ppm, Na 4200ppm, Sb 0.3 ppm, Se 0.7ppm, Ti 340ppm, U 0.8 ppm, Th 1.8 ppm, V 4.4 ppm, and Zn 68 ppm. Total sulfur content averaged 0.44% in section 1 and 0.48% in section 2. Mean concentrations of these elements are low when compared to western Canadian coals of similar rank, or to world coals (Swaine, 1990). Antimony, barium, and boron are enriched, with the latter being a reflection of the coal-forming environment. Despite the short lateral distanc...

This preliminary study reports on the concentration of selected elements of environmental concern, such as Be, Cd, F, Hg, Pb, and radionuclides, in subbituminous coals used exclusively for power generation in Alberta. Results show that the concentrations of these elements and radioactive nuclides in the coals studied are low compared to typical concentrations in world coals. The coals are "clean," suitable for use in coal-fired power plants, and their utilization has little impact on the environment. The potential fate of the elements and radionuclides is interpreted only in general terms, mainly by referring to previous studies on the behavior of trace elements and radionuclides during combustion.

The coal-bearing strata in the Basoren Formation from the Sariz-Karapinar coal region are of middle Miocene age and were deposited in a lacustrine environment. Coal in this formation is lignitic in rank (%Ro, random of eu-ulminite B is 0.37). These lignites have high inertinite content (up to 37.4%), which is higher than in any other Turkish lignites studied previously. Inertinite content in the region increases from the northeast to the southwest, possibly indicating oxidation of organic matter in the coal-forming environment due to lowering of the water level. Total sulfur content in the lignites ranges from 1.8 to 4.8%. High-rank coals present in the Upper Permian Yigiltepe Formation (%Ro, random is 0.66-0.70) contain more sulfur (Stot = 5.6-6.9%) and less inertinite (9.6-12.1%).

Results of ash chemistry composition on highwall channel samples, coal seams 1–6, cut W86, Whilewood Mine, reveal that low SiO2 / Al2O2 ratios are associated with high electrostatic precipitator (ESP) opacity. This ratio varies from 2·26 in seam 3 to 5·81 in seam 4, and is a good indicator of the clay minerals present in the coal. A low ratio (

Subbituminous coals, taken from a freshly mined open pit as well as from nine drillholes in the Whitewood Mine, Alberta, were analyzed for their elemental and radionuclide concentration. Furthermore, the coal ash was analyzed for major oxides, and a comparison was made with coals of similar rank and present only 12 km away, in the Highvale Mine. The Whitewood Mine coals are “clean“ by world standards and do not contain any environmentally deleterious elements in excess amounts. They are suitable for utilization, but care should be taken to minimize the negative opacity effects on the electrostatic precipitators (ESPs). The low Na2O content in the coals, particularly in the open-pit samples, may affect ash resistivity. This could result in a decrease in the flow of current and thus a decrease in the precipitator efficiency. Certain trends of major oxides in the coal ash are observed in a north-south direction and are discussed, with particular emphasis on the Na2O distribution in the six coal seams. The Wh...

Mineralogical analysis of the Highvale Mine coals using X-ray diffraction (XRD) shows quartz, kaolinite, illite, and feldspars to dominate. Minor amounts of carbonate and unknown hydrate minerals are also present, and most minerals reported by XRD have been verified by scanning electron microscopy-energy-dispersive X-ray spectrometry (SEM-EDX) on selected samples using back-scattered electron imaging on coal pellets, The coal ash indices show the Highvale Mine coals to have low to medium propensity to form slagging or fouling deposits in the boilers. The relationship between ash content of mill samples and opacity in the electrostatic precipitators (ESPs) is not clear. However, there appears to be a correspondence between ash resistivity and ESP performance. As resistivity is a function of ash chemical composition, the differences in ash composition, notably in its Fe2O3 content, may have contributed to the increase in opacity recorded for seam 1. The production of submicron particles, via fragme...

This study reports on the enrichment and depletion of elements in selected suites of subbituminous coals from the Highvale Mine, Alberta, Canada and in their 120°C, 400°C and 800°C ashes. All elements analyzed in the raw coal are within the world range for coals and some small variations in elemental concentration were noted due to variations in ash content of the samples. Ashing at 120°C resulted in an enrichment of all elements by a factor of 1.5 × to 6.5 × in one suite of samples and by a factor of 5 × to 11× in the other suite. Generally, the elements Br and Se are enriched by a lower factor than other elements, Mo is absent in all 120°C ashed samples and the samples with the higher ash content show a smaller elemental enrichment than samples with lower ash content (cleaner coals). All elements in the 400°C ashed samples are enriched by a factor of 1.5 × to 6.5 × in one suite of samples and by 1.5 × to 9.5 × in the other. Surprisingly, the elements Br, CI and Se are enriched two- to sixfold, pointing ...

Coals from the Highvale Mine, central Alberta Plains, were studied in order to determine the quantity (range and mean values), affinity, and mode of occurrence of the elements present in these subbituminous coals. Detailed elemental analyses were carried out for all coal seams and interburden in two drillholes, HV901-84 and HV904-84. In total, 49 samples were analyzed from the 16-m-deep HV904-84 drillhole (approximately three samples per meter of succession) and 33 samples from the 10.8-m-deep HV901-84 drillhole (also three samples per meter of succession). Mean concentration of various elements in the highvale Mine coals are as follows, all others are below detection limits: Sb, 0.74 ppm; As, 3.82 ppm; Br, 286.4 ppm; Cl, 72.3 ppm; Cr, 11.5 ppm; Co, 3.25 ppm; Cu, 20.6 ppm; F, 74.3 ppm; Hg, 0.012 ppb, Se, 1.65 ppm; U, 2.57 ppm; Th, 5.6 ppm; and V, 17.1 ppm. by world standards, all mean concentrations, except Br in some instances, are relatively low and the coals are not enriched in any environmentally or industrially hazardous elements. Therefore, the Highvale coals are considered clean by world standards and suitable for utilization. The concentration of elements associated with minerals (clays and/or carbonates), such as K, Mg, Na, Th,more » U, V, and Zn, follows similar repetitive trends within coal seams throughout the coal-bearing succession, indicating that the pattern of coal formation is often cyclic and that these geochemical trends are related to the ash content of the coal and the parting location within the coal-bearing succession.« less

The elemental distribution in peat deposits from Fraser delta, British Columbia, Canada were examined on peat ashed at low temperature (90°C) using INAA, DCP, andAA. Chlorine, B, Br, Mo, Na, S, and U are sensitive indicators of the depositional environment of these peats. The distribution of elements is related to water salinity. High concentrations of Cl and Na are encountered in samples deposited in brackish water environment and in the contact between the peat and the sea water. The concentration of Cl and Na decrease with decreasing distance from the contact with sea water. Silicon has the lowest concentration on the top of the fresh water peat and the highest on or near the top of brackish water peat. The concentration of the “authigenic uranium” in peats appears to be related to water salinity. The highest values are found in brackish water peat, indicating that uranium is possibly concentrated by its interaction with salt and carbonates. Compared to the Clark value, the only elements enric...

Pyrite concentrates were obtained from seven successive coal seams of Upper Carboniferous age in the Sydney Coalfield of Nova Scotia. These concentrates were analyzed for forty-nine trace metals and oxides using INAA and ICPES. The data indicate that trace amounts of other sulphide phases (inclusions as arsenopyrile, galena, chalcopyrite), presumed epigenetic clay minerals, and zircon inclusions are associated with pyrite concentrates. The content of rare earths and actinides in these pyrites are age dependent and tend to be more highly concentrated in the younger seams. Pyritic oxidation in coal and resultant formation and dissolution of secondary sulphate minerals are one mechanism for trace-metal dispersion into the surface-water environment. The pyrite concentrates on average are arsenic-rich (range 240-2900 ppm, mean 1556 ppm). However, this As may form insoluble, stable organic-complexes, which remain as As-rich sediments in situ.

Organic matter present in uraniferous paleoplacer deposits in the Elliot Lake-Blind River region, Canada, falls into two distinct types based on morphology, reflectance in oil, and bireflectance. Organic matter of the second type is primary and biogenic and probably represents the metamorphosed remnants of cyanobacterial mats. It consists of finely laminated kerogens with high reflectance (%Romax — 4.02-7.31) and high bireflectance. Under cross-polars it shows a textural pattern similar to that of thinly laminated organic matter. The level of thermal maturation is in the range of prehnite-pumpellyite to lower greenschist metamorphic facies. The first type consists of homogeneous, globular, migrated bitumen. These bitumens are isotropic to weakly anisotropic with a reflectance ranging from 0.72 to 1.32% (Romax)Globular bitumen is essentially unmetamorphosed and follows the (normal) bitumen maturation pathway. Both types of organic matter have contributed to the uraniferous mineralization of the El...

Organic petrology and geochemical studies (Rock-Eval/TOC) were carried out on shales from the Besa River (Upper Devonian-Lower Carboniferous), Yohin, Clausen, Prophet, Golata, and Mattson Formations (Lower Carboniferous) in exposed sequences at Jackfish Gap-Yohin Ridge and in a subsurface section in the North Beaver River area of the Liard Basin. Basinal shales of the Besa River Fm. have TOC values ranging from 1 to 4% and contain abundant type II, dominantly amorphous, kerogen of marine origin. Shales in the Yohin Fm. (slope to neritic shelf), Clausen Fm. (basin and slope deposits), Prophet Fm. (carbonate slope), and Golata Formations are of mixed marine and terrestrial origins and yield TOC values of 1 to 3%

Approximately 130 core and drillhole cuttings samples taken from the Palaeozoic and Mesozoic of northwestern Melville Island were examined using reflected-light microscopy and Rock-Eval pyrolysis. The Triassic Schei Point marine silty shales, known to be good-quality source rocks in certain parts of the Sverdrup Basin, are dominated by kerogen Types I and II, have hydrogen index (HI) values as high as 625 mg hydrocarbon (HC)/g organic carbon, a total organic carbon (TOC) content as high as 8.07o, but are marginally mature at best. Source potential decreases drastically in the Jurassic and Cretaceous parts of the succession The Palaeozoic section is dominated by bitumen, and often numerous bitumen populations are identified based on morphology, texture, and optical properties. Bitumen reflectance increases with depth, following a trend almost parallel to vitrinite, an indication that it is primary and has been subjected to similar thermal stress. The upper Palaeozoic sediments are within the hydro...

A suite of 24 tonsteins from the East Kootenay Coalfields is studied for mineralogical and elemental composition, origin, and the degree of physical and chemical alteration, using x-ray diffraction (XRD), x-ray fluorescence (XRF), instrumental neutron activation analysis (INAA), and inductively coupled plasma (ICP). Concentration of elements greater than the Clarke value is often limited to the litho-philes, i.e., Al. B, Ba, Cr. Co, Cs, Cu, Fe, K, Rb, Mg, Si, Sr, Th, and U, and some chalcophiles, i.e.. As, Sb, Se, and Mo. However, some lithophiles, such as Br, Ca, and CI, are depleted in these samples. The elements Al, Ca, Co, Hf, K, Mg, Na, Th, Se, U, andREEs (rare earth elements) are sensitive indicators of origin and degree of alteration of these tonsteins. Statistical analyses allow indirect observation of the stages of leaching that have affected the tonsteins. The Kootenay tonsteins are divided into two groups based on their mineralogy and elemental composition: (1) tonsteins rich in Ba and...

Thermal alteration of both organic and inorganic components of a coal seam from Telkwa, British Columbia, is examined, using reflected light microscopy, x-ray diffraction (XRD), and neutron activation analysis (INAA). The alteration resulted from intrusion of an alkali basaltic dike. The organic components of coal (macerals) at the contact with the intrusion are coked and developed strong anisotropy. The temperature of formation of this coke is estimated at >750°C and possibly >900°C with a fast rate of heating. However, coal at a distance of 120 cm from the dike is unaltered. Some liptinite macerals retained their original morphology in the altered residue but developed stronger anisotropy than the altered coal groundmass. Pseudovitrinite became reactive and developed fluidity in the altered coals. Original botanical morphology of pseudovitrinite superimposed by mosaic textures is still present in altered coal. Assimilation of less reactive components of coal by reactive components is observed i...