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Coal and interbedded rocks from the two coalfields in the southern intermontane region of British Columbia, Canada, deposited in fluvial-lacustrine, and lacustrine were examined using reflected lig...

A 59 m-thick section of a freshwater oil shale interbedded with marlstone of Lower Carboniferous (Tournaisian) age from the Big Marsh area in Antigonish Basin, Nova Scotia, Canada, was examined using reflected light microscopy, Rock-Eval pyrolysis, X-ray diffractometry analysis, inductively coupled plasma-mass spectrometry for elemental analysis, and prompt y for boron concentration. The oil shale was deposited in a lacustrine environment based on geology, sedimentology, variation in organic matter, and boron content (28-54 ppm). Organic petrology classified the oil shale into three broadly distinct types. Type A oil shale is a coastal facies shale containing terrestrially derived macerals, such as vitrinite and inertinite, sporinite, with some lamalginite, and amorphous bituminous matrix. Type B oil shale was deposited in a shallow-water facies and contains mostly lamalginite and some vitrinite and sporinite. Type C oil shale is a relatively deep-water facies, associated with open-water Torbanite-type oil shale and contains mostly Botryococcus colonial telalginite. The oil shale is thermally mature (T-max is 441-443 degrees C). Total organic carbon (TOC) varies from 5.8 to 7.3 wt %, and the hydrogen index is between 507 and 557 mg HC/g TOC. The rate of sedimentation as determined by the Th/U ratio indicates possibility of three sedimentation periods: an irregular but mostly slow rate of sedimentation from the base of the section up to 68 m, followed by a regular and slow rate between 68 and 53 m, and a regular and fast rate between 53 m and the top of the section. The higher Th/U ratio during deposition of the shallow-water facies was due to the input of allochthonous U. The redox conditions, as reflected in the variation of Cr to Mo, U, and Ni + V, indicate that the oil shale was deposited under suboxic-dysoxic conditions. The high organic productivity by phytoplankton and bacteria is characterized by a low Cr and high V/Cr ratio and suboxic conditions. In contrast, the well-oxygenated and uniform, warm-temperature upper water level supports a dysoxic environment. Variation of Sr/Ca vs Mn/Ca ratios indicates that most samples have low values, a characteristic of colder water and high terrigenous influx. The post-Archean Australian shale (PAAS)-normalized rare earth elements (REEs) follow three trends. Type A oil shale has the highest concentration of total REEs (648 ppm) and light REEs (LREEs, 605 ppm) as compared with type C (269 and 233 ppm), which are less than half of type A. Type B oil shale has the lowest total REEs (184 ppm) and LREEs (152 ppm). The concentration of heavy REEs decreased from 43 ppm in type A oil shale to 36 ppm in type C oil shale. Comparison of PAAS-normalized REEs for the three oil shale types indicates a reduction of the negative Eu anomaly with depth, which is possibly related to sedimentary sorting as a result of accumulation of fine sediments in the deeper water zone of the lake. The concentration of most elements of environmental concern is similar to and/or lower than the world shale. However, there are instances of higher concentrations of hazardous elements (e.g., As, Cd, Mo, and Se ).

Samples of the Carboniferous oil shale of the Albert Formation in New Brunswick, Canada, were examined using reflected white and fluorescence light microscopy, Rock-Eval pyrolysis, and ICP-MS (for elements). The presence of fractured filled solid bitumen in contact with and within the Albert Formation oil shale indicated that migrated oil had enough force to overcome the tensile strength of oil shale matrix and penetrate the oil shale. Migrating fluid caused thermal alteration of the matrix as evident by the presence primary bitumen and oil droplets. The evidence of oil migration included the presence of solid bitumen and crystalline carbonates in contact with the oil shale. The low permeability oil shale acted as a seal/aquitard and created a diagenetic ‘front’ by slowing the advance of migrating oil, resulting in the formation of a reaction zone. Migrated solid bitumen consisted of both soluble solid bitumen types such as gilsonite and glance-pitch, and insoluble solid bitumen such as wurtzilite and albertite. The variation of Th/K ratio and TOC (wt%) indicates that most of oil shales from the Albert Mine area and within the vicinity of oil migration have higher content of TOC (17–25 wt%) compared to the other Albert oil shales (TOC =

Fine particles (PM 2.5 ) emitted from the stacks of the coal-fired power plants are of environmental concern since they can easily enter the human respiratory track. The detailed study of the fly ash particles using scanning electron microscope/electron dispersive spectrometry (SEM/EDX) show that fine solid spherical particles (microspheres) are contained by the large cenosphere particles (>50 μm) during the combustion process. The resulting macro particles are known as “plerosphere”, which are typically impregnated by the fine microspheres. The coal-fired power plants’ particle control devices such as the electrostatic precipitators (ESP) and baghouse filters tend to capture the large plerospheres, more efficiently. Therefore, the result of this study suggests that the containment of the microspheres by plerospheres during the coal combustion process can effectively reduce the amount of fine particles and associated elements released into atmosphere.

Fly ashes produced from Canadian power plants using pulverized coal and fluidized bed combustors were examined for their carbon content to determine their ability to capture mercury. The feed coal used in these power plants were lignite, subbituminous, high and medium volatile bituminous, their blends, and also blends of coal with petroleum coke (Petcoke). The carbon and mercury content of the coals and fly ashes were determined using the ASTM standard method and by the cold vapour atomic absorption spectrometry method. The carbon content of the fly ash was concentrated by strong acid digestion using HCl and HF. The quantitative and qualitative analyses of the carbon concentrate were made by using a reflected light microscope. The results show that the carbon content of fly ash appears to be partially related to depositional environment during coalification and to the rank of the coal. The Hg captured by the fly ash depends on the rank and blend of the feed coals and the type of carbon in the fly ash. The isotropic vitrinitic char is mostly responsible for the capture of most Hg in fly ash. The inadvertent increase in carbon content due to the blending of coal with petroleum coke did not increase the amount Hg captured by the fly ash. The fly ash collected by the hot side electrostatic precipitator has a low Hg content and no relation between the Hg and carbon content of the ash was observed. These results indicate that the quantity of carbon in the fly ash alone does not determine the amount Hg captured. The types of carbon present (isotropic and anisotropic vitrinitic, isotropic inertinitic and anisotropic Petcoke), the halogen content, the types of fly ash control devices, and the temperatures of the fly ash control devices all play major roles in the capture of Hg.

Feed coals and fly ashes from two coal-fired power plants burning Alberta subbituminous coal were analyzed for C, Cl, Hg, and S and calorific values (for feed coal only), every week for a period of 33 weeks. The feed coals used in this study were deposited in brackish water and are compared to the coals deposited in a freshwater environment. The Hg and char (unburnt carbon) content of the fly ash was monitored to determine the variation of Hg and its possible relationship to the char types in the fly ash. The feed coals have Hg content of 0.026–0.089 mg/kg and their fly ash contains 0.02–0.243 mg/kg of Hg. The C content of the fly ashes ranges from 0.15% to 0.51%. The carbon/char was separated from the fly ash using HF and HCl. Reactive vitrinitic (formed from woody part of plants) and less reactive inertinitic (natural char) chars were separated by density separations of various specific gravities using ZnBr 2 . The char is mostly reactive vitrinitic (67–80 vol.%). Both stations have similar range of C content for their respective fly ashes. However, station 2 shows a much wider range of Hg in fly ash compared to station 1. In general, the fly ash from coal deposited under brackish water environment (stations 1 and 2) appears to have same or higher Hg content for lower C content compared to the fly ash from coal deposited under fresh water environment. The calculated emitted Hg for the period of 33 weeks for station 1 is estimated to be 64–90% of the total input of Hg with an average of 74%. The calculated emitted Hg shows a more complex pattern for station 2 and falls into two groups; with group (a) showing higher enrichment index for both Hg and S. The calculated emitted Hg for this group is 43–74% with an average of 57%, indicative of more Hg being captured by fly ash, possibly due to interaction between Hg and S. In the second group (b) the emitted Hg is calculated to be 74–95% with an average of 85%. The relative enrichment of both Hg and S in group (b) is low compared to group (a), indicative of possible slight paleo-weathering of the feed coal. The present study indicates that geological parameters such as paleo weathering and also depositional environment of the feed coal may influence the Hg content of fly ash.

Fly ashes were collected from the electrostatic precipitator (ESPs) and/or the baghouse of seven coal-fired power plants. The fly ashes were sampled from power plants that use pulverized subbituminous and bituminous feed coals. Fly ash from bituminous coals and limestone feed coals from fluidized-bed power plant were also sampled. The fly ashes were examined for their mineralogies and elemental compositions. The fly ashes from pulverized low sulfur coals are ferrocalsialic, those from high sulfur coals are ferrosialic and the fly ashes from the fluidized bed coals are ferrocalcic. The concentrations of As, Cd, Hg, Mo, Ni, and Pb in fly ash are related to the S content of the coal. Generally, those feed coals with a high S content contain higher concentrations of these elements. The concentrations of these elements are also greater for baghouse fly ash compared to ESP fly ash for the same station. The S content of fly ash from high S coal is 0.1% for pulverized ESP fly ash and 7% for baghouse fly ash from the fluidized bed, indicating that most of the S is captured by fly ash in the fluidized bed. The baghouse fly ash from the fluidized bed has the highest content of Cd, Hg, Mo, Pb, and Se, indicating that CaO, for the most part, captures them. Arsenic is captured by calcium-bearing minerals and hematite, and forms a stable complex of calcium or a transition metal of iron hydroxy arsenate hydrate [(M 2+ ) 2 Fe 3 (AsO 4 ) 3 (OH) 4 ·10H 2 O] in the fly ash. Most elements in fly ash have enrichment indices of greater than 0.7 indicating that they are more enriched in the fly ash than in the feed coal, except for Hg in all ESP ashes. Mercury is an exception; it is more enriched in baghouse fly ash compared to ESP. Fly ash collected from a station equipped with hot side ESP has a lower concentration of Hg compared to stations equipped with cold side ESP using feed coals of similar rank and mercury content. Fly ash particles from fluidized bed coal are angular and subangular with cores of quartz and calcite. The quartz core is encased in layer(s) of calcium-rich aluminosilicates, and/or calcium/iron oxides. The calcite core is usually encased in an anhydrite shell.

Particles emitted from three coal-fired power plants burning subbituminous coals from Alberta, Canada were examined for total particulate matter (PM) and size fractions PM >10 , PM 10 , and PM 2.5 . The sampling was carried out following EPA Method 201A, which requires a 6 inch port. Three tests were performed at each station. The rates of emitted particulates from the three power plants are 9.9–53.4 mg/m 3 (dry), 30–90 kg/hr (dry), and 0.039–0.118 kg/MWh, respectively. The emission rates of the various particle sizes for these three power plants are 8.7–39.5 kg/hr of PM >10 , 10.7–40.8 kg/hr of PM 10 , and 9.65–10.7 kg/hr of PM 2.5 . The present results indicate that 29–44% of emitted particles are PM >10 . The total emissions of particulates from two power plants are below the Canadian Guideline for emission from a coal-fired power plant (0.095 kg/MWh), while the third power plant is slightly higher than the Guideline (0.118 kg/MWh). The malfunctioning of control technology may result in unrealistic and wide variation in the measured rates of emitted particles.

Particles emitted from coal-fired power plants burning subbituminous coal from Alberta, Canada were examined for total particulates (PM) and size fractions PM>10, PM10, and PM2.5. The sampling was carried out following EPA Method 201A. Three tests were performed at each station. The emitted particles were examined using SEM/EDX and gravimetric method for the determination of their sizes. The elemental composition of particles was determined using INAA and ICP-MS. The particles emitted from the stack are classified based on their morphologies and chemistries to the following: unburnt carbon, feed-coal minerals such as quartz, and by-products of the dissociation, fractionation, and contamination by minerals in coal. The emitted particles are mostly spherical and their matrices are composed of aluminosilicate minerals containing calcium. The PM>10 fraction contains small plerospheres, fragments of char, and angular quartz and feldspar particles. The PM10 fraction contains solid spheres and cenospheres, gypsum needles, and particles of char. The PM2.5 particle size fraction is mostly composed of solid spherical aluminosilicates with some surface enrichment of elements such as Ba, Ca, and Fe. The composition of emitted particles is ferrocalsialic. Most elements in the particle size fractions are Class I or II, such as Al, Ca, and Fe. Cd, Cu, Mo, and Ti were only detected in PM2.5 fraction.

The chromium species in the feed coals and ash byproducts from seven Canadian coal-fired power plants were examined using Cr X-ray absorption near-edge spectroscopy. Chromium in the Canadian feed coals is always found as Cr{sup 3+} but generally has a dual occurrence, as Cr{sup 3+} is distributed to varying degrees between the clay mineral illite and a poorly crystallized chromium oxyhydroxide phase associated with the organic fraction. In two subbituminous feed coals from Alberta, chromium is present largely as Cr{sup 3+}/illite, whereas in two other such coals, it is present predominantly as CrOOH. Chromium in a low-sulfur bituminous feed coal from Alberta is found mostly as Cr{sup 3+}/illite, whereas for feed coals from Nova Scotia with high sulfur contents, chromium is distributed between both Cr{sup 3+}/illite and CrOOH. Very little chromium was found in the limestone used in a fluidized-bed combustor. The chromium species in most bottom ash samples from all seven combustion units is predominantly, if not entirely, Cr{sup 3+} associated with aluminosilicate phases. Chromium speciation for subbituminous electrostatic precipitator fly ash is mostly Cr{sup 3+}, but in some cases, it is slightly lessand varies by sampling location at the plant. Chromium in fly ash from the combustion ofmore » bituminous feed coals is predominantlyCr{sup 3+}. A unique species of chromium found in one feed coal and an unrelated fly ash is metallic chromium, similar to that in stainless steel. The occurrence of this form of chromium in these materials indicates contamination from machinery, such as the coal milling machine or possibly wearing down of stainless steel parts by the coal or ash. The observation of this unexpected contamination demonstrates the power and usefulness of X-ray absorption fine-structure spectroscopy for speciation determination. 35 refs., 6 figs., 4 tabs.« less

The arsenic species in the feed coals and ash byproducts from seven Canadian power plants (including one with a fluidized-bed combustor) that were burning local sub-bituminous and bituminous coals with sulfur contents in the range of 0.30−3.5 wt % have been examined using As X-ray absorption fine structure (XAFS) spectroscopy. The feed coals can be grouped based on their contents of arsenic associated with pyrite (As/pyr) and as As3+ and As5+ (arsenate) species. The arsenic species in sub-bituminous feed coals with low sulfur (0.22−0.38 wt %) and arsenic (1.6−2.2 mg/kg) contents consist of ∼50% As3+ and ∼50% As5+, whereas those with moderate sulfur (0.50 wt %) and arsenic (3.63 mg/kg) contents consist of 84% As/pyr, 7% As3+, and 9% As5+. In bituminous feed coal with low sulfur (0.40 wt %) and arsenic (4.39 mg/kg) contents, the arsenic speciation consists of 34% As/pyr, 12% As3+, and 54% As5+, and for those with high sulfur (2.60−3.56 wt %) and arsenic (54−84 mg/kg) contents, it consists of 77%−82% As/pyr ...

Feed-coals used in some Canadian power plants were examined for their mineralogical and elemental composition. The mode of occurrence of elements (organic/minerals) in these samples were determined using sequential leaching by H 2 O, NH 4 OAc and HCl. Canadian feed-coals examined in this study are subbituminous to bituminous rank (calorific values: 19.62–29.88 MJ/kg). The sulphur content of these coals is 0.32–3.55%. Quartz and aluminosilicates (clay minerals and feldspar) dominate the mineralogy of these samples. The accessory minerals consists of pyrite, sphalerite, barite, calcite, anhydrite, chromite, zircon, biotite, and monazite, which occur as both primary and secondary cell filling types. An interesting mineral found in one of the subbituminous feed-coals is the gorceixite that is normally associated with degraded volcanic ash. The sulphur content of the feed-coals is an indication of their geological setting with feed-coal formed in a fresh water setting containing the least amount of S and those associated with evaporites having the highest S content. The concentrations of Cd, Cr, Cu, Hg, Ni, Se, V, and Zn in these Canadian feed-coals are low compared to world coals. Mercury content of these feed-coals ranges from 0.04 to 0.16 ppm. Mercury is mostly associated with the pyretic portion of coal and has direct correlation to As and S content in these coals. Arsenic in low sulphur coals is mostly associated with coal macerals and in higher sulphur coals with pyrite. About 47% of As in high sulphur coal is removed after leaching by HCl. Water soluble elements consist of Co, Ni and Mn, which are associated only with bituminous feed-coals. The removal of these elements by water is possibly due to an increased acidity of leaching solution and presence of soluble Cl and S. Beryllium and vanadium in low S coals are mostly removed after leaching by HCl, indicating a possible association with clay minerals. Limited Be and V is removed from lower clay mineral content coals; however, in high S content coals, more Be and V are removed. The speciation of As, Cr and Ni indicates that As is mostly present in the less-toxic form As +5 and Cr is present entirely as Cr 3+ , an essential human trace nutrient, found in both subbituminous and bituminous ranked coals. Nickel is present mostly as Ni 2+ in oxygen coordination in these milled coals and carcinogenic compounds of nickel are not present in these feed-coals.

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

This study reports on the elemental concentrations and vertical variation of coal seams from the Obed Mountain deposit, Alberta Foothills, Canada. Results from two sections of Seam 1 show that the major elements (i.e. Al, Fe, Mg, K, Na, Ti, and Si) have high concentrations in intervals having high ash content, with the only exception of Ca. Similarities are apparent, in both sections, in the vertical variations of Th, U, Se, and Zn; Rb, Cs, and K; Sb, Mo, and W; Mn and Sr; and Ba, Cr, Co, Hf, and Sc. These similarities are also evident among the REEs, notably between Ce and La; also between Dy, Eu, and Sm. Most elements, with the exception of Ba and Sr are slightly more concentrated in Section 2 of Seam 1, located approximately 1.5Fig. km away from Section 1. Compared to Seam 1, Seam 2 has lower mean concentrations of elements. Boron in the coal ranges from 27 to 100 ppmw, though most values are less than 50 ppmw. Boron concentrations suggest a freshwater depositional environment. The element is depleted in the sedimentary partings (12–29 ppmw only) and is enriched in the coal interval near the roof and immediately beneath the partings. This enrichment shows possible downward mobilization of boron. Vertical variations of elements are helpful in delineating the boundaries between coal and sedimentary partings in the succession. The Obed Mountain coals are “clean” by world standards and their elemental concentrations are comparable with those in coals of a lower rank from the same coal formation used for power generation in Alberta. All sedimentary partings have low concentrations of Ba, Hf, Sc, Sr, Ta, Th, U, and REEs; this, along with the absence of an Eu negative anomaly suggests a non-volcanic origin for the partings.

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...

Fluorine was determined in 57 samples of coals from western Canada and the Yukon (47 bituminous, 4 subbituminous, 6 lignite) by a pyrohydrolysis method. The range of values is 31–930 ppmw F in dry coal, the lowest values being mainly for the low-rank coals. For bituminous coals most values are in the range 31–580 (mean 174) ppmw F.

The concentration of 58 elements in Byron Creek coals ( % Ro = 0.942 1 .05 ), and their 1000 °C ashes were determined using intense neutron activation and plasma emission spectrometry. The organic-inorganic affinities of elements were detected by the trend of element concentration versus ash content of the samples. Antimony, boron, bromine and selenium are the only elements that are enriched in these coals. The higher concentration of boron in one coal seam is considered to indicate that this seam was deposited in a more marine environment than the other seams. Coal seams can be identified by the concentration or depletion of certain trace elements, such as boron, sodium, thorium and uranium. Similarity indices of coal samples are also a useful tool in seam identification. Certain elements, for example gallium, thorium and uranium, are more concentrated in carbominerite from the roof or floor than within the coal. Regular variation of boron, sodium, thorium and uranium may indicate the repetition of certain units in tectonically thickened coal seams.

Isotropic to anisotropic pyrolytic carbon was observed in Canadian subbitumonous to bituminous coals (% R oil = 0.50−1.0) using reflected light microscopy. Morphologically, pyrolytic carbon consiste of large, well-developed spherulitic and laminated forms occuring in coal macerals and carbominerites as cell and crack filling. The spherulitic forms probably developed rapidly and laminated forms over a period of time. The presence of pyrolytic carbon in coal may indicate a thermal event and, in these coals it is of detrital nature and therefore should be grouped with inertodetrinite.

The occurrence of coal is related directly to the climate of a given geological age which, in turn, is determined by the extent of the seas, regional geography, the configuration of the land masses and therefore, by the ongoing process of continental drift. Of major importance also is the relative vertical movement of the coal-forming basins, resulting from tectonic movement, which affects the rate of burial and the coalification process. In this review the changes in climate and continental positions, relative to coal formation, are described from the early Carboniferous to the Tertiary. The genetic relationships between different coalfields, in terms of the flora of the period are commented upon and it is suggested that by studying the palaeogeography of the world it is possible to correlate apparently unrelated coalfields.

The effects of atmospheric oxidation at 378 K upon the carbonization of a coking and a caking vitrinite have been examined in terms of the origins and extents of development of anisotropic material. The vitrinites, oxidized from 1 to 40 days, were carbonized to temperatures between 618 and 878 K, in open boats under nitrogen at atmospheric pressure, and in sealed gold tubes at maximum pressures of 140 to 310 MPa. Optical microscopy was used to observe, qualitatively, changes in reflectance and in shape and size of the anisotropic material of the carbonized product; morphological changes were monitored by scanning electron microscopy. For both vitrinites, whereas one day of oxidation destroyed coking properties and almost all of the anisotropic development in the open-boat carbonizations, the pressure carbonizations were not significantly affected until after five days of oxidation. Anisotropy still developed by mesophase growth from the plastic phase of carbonization, to produce the shaped, botryoidal material characteristic of pressure carbonizations. Thereafter, although in the pressure carbonizations the particles of coking vitrinite only fused slightly at interfaces to form a coherent product, marked increases occurred in reflectance and in observed anisotropy, showing maxima at nine days of oxidation. Results are interpreted on the assumption that oxidation cross-links the macromolecular structure of the vitrinite substance. The effect of high pressure during carbonization after five days of oxidation is to preserve and perfect the original basic anisotropy of the vitrinites initially stabilized by the cross-linkage of oxygen atoms.

Three vitrinites (C = 80.0, 87.9 wt%, daf and 94.2 wt%, dmmf) have been heat-treated over the temperature range 1000–2400 °C in the presence of argon. The variation of morphological and optical properties of the heat-treated samples is studied systematically using reflected-light microscopy. An optically isotropic, highly reflecting material is formed on the surface of anisotropic particles of two of the vitrinites (C, 80 and 94.2 wt%) during semi-graphitization (1000–1400 °C), which decreases in extent with increasing temperature and is absent at the end of this stage. The development and subsequent disappearance of the isotropic material is probably due to the evolution of volatile matter and subsequent deposition of pyrolytic carbon during semi-graphitization. The continuous increase of bireflectance of these two vitrinite residues, with heat-treatment temperature, indicates progressive improvement in the ordering of the molecular structure. The reflectance of the heat-treated anthracitic vitrinite (C, 94.2 wt%), increases continuously whereas the reflectance of the heat-treated low-rank vitrinite (C, 80 wt% decreases slightly from a maximum during semi-graphitization. The third vitrinite (C, 87.9 wt%) does not develop an optically isotropic highly reflecting material on particle surfaces during semi-graphitization. However, this vitrinite softens during carbonization (25–1000 °C) producing a residue with a mosaictype anisotropic microstructure. The condition of polished surfaces prepared from residues of this vitrinite from the semi-graphitization to crystallization stages (1000–2300 °C) deteriorates, values of bireflectance and reflectance decrease continuously with increasing temperature. This appears to result from a reduction in the surface hardness of particles of this vitrinite residue resulting on transformation from two-dimensional ordering to three-dimensional graphitic ordering.

Vein, lens and stratiform natural sedimentary bitumen deposits were analysed by combined geochemical and micropetrographic techniques. Reflectances in oil, air and water, fluorescence spectral properties, solubility in dichloromethane, elemental analysis and bulk chemical composition of soluble fractions by chromatographic separation indicate that these materials are generally gilsonite bitumen, although some, showing evidence of significant alteration and weathering, are closer to albertite in composition. Optical properties show that the bitumens are immature and fall within the field of asphaltites on the bituminization curve. Fluorescence spectra generally show two maxima, again a feature associated with immature gilsonite bitumen. Capillary-column g.c. of saturates fractions indicates the absence of normal and acyclic isoprenoid alkanes, these fractions being dominated by a series of C27-C34 pentacyclic triterpanes of the hopane family. The saturates fraction composition is characteristic of biodegraded crude oils, and molecular biomarker stereochemistry indicates a moderately mature petroleum source. All the bitumens are shown to have a common genetic origin and are thought to be the result of in situ alteration and biodegradation of oil infillings in joints, fractures and bedding planes, resulting from fracturing and faulting of reservoir and overlying cap rocks associated with a period of Neogene tectonism.

Vitrinite-rich samples from a weakly caking and a strongly coking coal have been carbonized both fresh and after preoxidation for 14 days at 105 °C to points within the temperature range 300–800 °C. Conventional reflected-light microscopy shows that pronounced reduction in softening capacity and devolatilization of carbonized preoxidized reactive macerals are accompanied by microscopical features which contrast with those of the same reactive macerais when carbonized fresh. Most noticeable is the retention of the original petrographical structure of the coals when carbonized after preoxidation, even at temperatures of 800 °C. No mosaic is formed in the preoxidized reactive macerals, although a general anisotropy gradually develops; some vitrinitic particles attain a very high degree of anisotropy though all of this development takes place in the solid state. The level and trends of the average bulk bireflectances of both forms of carbonized vitrinite are similar, but the rapid bireflectance rise characteristic of vitrinites carbonized above ≈ 600 °C probably begins earlier in preoxidized than in fresh vitrinites. This could happen if preoxidation raises the aromaticity of the original vitrinite, so allowing reorientation of the lamellae to begin at lower temperatures. Comparisons are made with earlier observations.

The dispersion of optical properties (e.g. reflectance, refractive and absorptive indices) of graptolite epiderms in early Paleozoic sediments with low to high maturity levels (conodont alteration index = 1–5) has been determined in the visible spectrum (450–650 nm). The results were compared with those for vitrinite of different rank and asphaltic pyrobitumen. The dispersion follows similar trends to those of coal macerais such as resinite, vitrinite, and also asphalt and pyrobitumen. This indicates similar molecular structural changes, e.g. an increase in aromaticity and ordering of aromatic carbons for graptolite epiderms with increased maturity. The dispersion of optical properties of graptolites in sediments with a low maturity level falls from blue to red in the visible spectrum, indicating low aromatic carbon content. Those in more matured sediments rise from blue to red indicating high aromaticity and molecular ordering for these graptolites. Graptolite epiderms are sensitive to a rise in temperature and are a good indicator of the maturity of early Paleozoic sediments.

Liptinitic macerals in medium and low-volatile bituminous coals (C=87.9 and 90.0 wt% daf) which have undergone a plastic stage during primary carbonization (

Chemical and petrological analyses were carried out on several British Columbia coals which are known as ‘needle’ coals because of the pine needle morphology exhibited on weathering. The object was to determine the nature of the precursor and thus to identify the component maceral as resinitic or algal. Infrared spectroscopy, saturate fraction gas chromatography, pyrolysis chromatography, gas chromatography-mass spectrometry, organic elemental analysis and reflectance and fluorescence microscopy were used. While the i.r. properties are consistent with previously published results on resinite, the other chemical results suggest that the present materials are not obviously related to any given member of the liptinite group of macerals. High concentrations of extractable hopanoid hydrocarbons are interpreted as resulting from high contribution to the biomass by bacterial debris. The petrological results suggest that the main constituent of the ‘needles’ can be best described as bituminite II or III derived from non-algal lipids. This conclusion is also supported by the observed associations of the other identifiable macerals. The results indicate that the ‘needles’ have been chemically and petrologically homogenized from a liptinite-rich precursor with minimal algal input. The present morphology may have been preserved from resin rodlets which have been severely altered by catagenetic or biological mechanisms or both.

A partially combusted and coked coal seam from Aldridge Creek, British Columbia, Canada, was studied using reflected light microscopy. Three zones, namely combustion, distillation and unaltered coal were detected. Combustion had taken place in the uppermost part of the coal seam, immediately below the melted roof rock, the only evidence of combustion being the presence of coke showing oxidation rims. The distillation zone encompassed most of the coal seam; different stages of carbonization were evident in the samples from this zone, with a coke subzone occurring at the top and a precarbonization subzone at the base. Samples from the coke subzones show granular anisotropy; the reflectance and bireflectance of medium grained mosaic are higher than those measured on fine grained mosaic in the same samples from this zone. An unaltered coal zone occurred at the base of the coal seam.

This Paper describes the optical properties of chitinous material found in Canadian subbituminous coal (%/ R oil = 0.65). The chitinous material was examined using reflected, transmitted and fluorescent light microscopes. Morphologically, chitin is distinguished from other coal macerals by possession of a two-layered structure with a fibrous layer contiguous with a finely porate lamellar layer. The chitin is low reflecting, and shows fluorescence colour and spectra similar to resinite in coal.

Resinite concentrate from a subbituminous coal ( R oil = 0.45%) was oxidized in air for 1 h intervals at fixed temperatures between 50 and 400 °C. The oxidized residues were examined using reflected white and fluorescent light microscopy. Three phases of oxidation were observed. Phase I (50–125°C) was marked by an oxidation rim with lower reflectance than the main mass of resinite, perhaps indicating chemisorption and decomposition of the chemisorbed components. Phase II (150–350°C) was apparent from the development of two oxidation rims, the outer of higher and the inner of lower reflectance than the main mass of resinite, perhaps indicating an ‘oxycoal’ phase. Phase III (〉 350° C ) was marked by a sharp increase in reflectance of the outer oxidation rim and a similarity in reflectance between the inner oxidation rim and main mass of resinite, perhaps indicating a ‘combustion phase’. The fluorescence properties (colour, wavelength of maximum intensity and red-green quotient) of the oxidation rims shifted from green towards the red region of the spectrum with increasing oxidation temperature and were a good indicator of the progress of oxidation.

A study is made of the morphological and optical properties of a blend of concentrated sporinite and vitrinite macerals (equal parts) from the same coal carbonized between 400–900 °C at 5 °C/min under nitrogen. Two coals of different rank were used and the results compared with properties of unblended carbonized sporinites. Coke from a blend of low-rank vitrinite and sporinite produced a two-phase optical texture, whereas coke from the medium-rank vitrinite and sporinite mixture produced a three-phase optical texture. A ‘Transitional Zone’ of optical texture was observed at interfaces between carbonized vitrinite and sporinite, this zone being wider for the coal of higher rank. The increase of bireflectance in oil with carbonization temperature of the sporinite in the blends was lower than for the carbonized unblended sporinite, caused by a reduction in fluidity of sporinite with blending. The decrease of refractive index for sporinite carbonized > 600 °C in the blends was lower than that of the unblended sporinite.

Vitrinites ranging from sub-bituminous to anthracitic rank have been heated at 150 and 350 °C for residence times extending up to 32 weeks. Devolatilization vacuoles develop in all the vitrinites at 350 °C, apart from the anthracitic. Occasional small vacuoles formed in the vitrinites of coking rank at 150 °C are most probably related to gas evolution from liptinites. Slight rounding of the margins of vitrinite particles of coking rank at 350 °C indicates softening, while heating at the longest residence time has been sufficient to allow vitrinites of coking rank to undergo ‘active decomposition’. Mosaic structures have developed at temperatures as much as 125 °C below those normally attributed to the formation of such structures in short-term laboratory carbonization experiments on vitrinites of the same rank. Again, apart from the vitrinites of anthracitic rank, the reflectance of vitrinites shows a rise at 150 and 350 °C that would continue beyond the longest residence time used. At 350 °C a large part of the reflectance increase occurs during the first week of heating. The reflectance data and the derived refractive and absorptive indices indicate that with sufficiently long residence times, changes that are more fundamental than ‘molecular stripping’ must take place, probably involving condensation reactions that introduce increased coplanarity into the vitrinite molecules. The implication of these data to thermal metamorphism of coals and to the normal coalification process is briefly discussed.

Summarization: Major and trace element analyses were performed on coals from various locations in western Canada, and on low-temperature (150 °C) and high-temperature (1000 °C) coal ash produced from these coals. Elemental analyses were carried out by X-ray fluorescence spectroscopy and intense neutron activation analyses. Based on their trace elements, the coals in this study fall into two groups: 1. low-rank coals (lignite-subbituminous) of late Cretaceous and Tertiary age; and 2. high-rank coal (bituminous-semianthracite) of Jurassic-Cretaceous age. The elemental analyses of the coals and coal ash indicate that the local conditions had considerable influence on the concentrations of certain trace elements. Antimony and selenium in coals are the only elements which are enriched relative to concentrations in the earth's crust; arsenic is concentrated in lignite to subbituminous coal, but is depleted in bituminous-anthracite coals; as expected the ash of these coals showed many more instances of enrichment. Presented on: Fuel