Volatile Bituminous Rank Research Articles

The hydrophobicity of coal macerals

The captive bubble and sessile drop contact angle techniques have been used to evaluate the hydrophobicity of petrographically identified coal macerals. The magnitude of the contact angle on vitrinite is shown to be a function of coal rank (%C, %O and % vitrinite reflectance), increasing with increasing rank to a maximum for low volatile bituminous rank coals then decreasing for anthracite. The least data scatter is found when vitrinite reflectance is used as a rank parameter. Contact angles measured or estimated for other discrete macerals, indicate a variation in hydrophobicity based on coal type. These data correlate well with known flotation results.

Coal Rank Trends in Western Kentucky Coal Field and Relationship to Hydrocarbon Occurrence: ABSTRACT

Abstract Vitrinite maximum reflectance trends for the Middle Pennsylvanian Springfield (No. 9) coal bed in the Western Kentucky coalfield indicate that coal rank is high volatile A bituminous (0.70-0.85% Rmax) in portions of the Webster syncline in Webster and Union counties (south of the Rough Creek fault zone) and is generally high volatile C bituminous (<0.60% Rmax) in the remainder of the coalfield. Within the Webster syncline, the reflectance of the Springfield coal does not vary significantly despite a difference in elevation of nearly 300 m. Reflectance gradients in the Webster syncline are not well defined; reflectances are generally highest in the Baker (No. 13) coal bed and are lower in the underlying Herrin (No. 11) and Briar Hill (No. 10) coals. Rank trends from the Springfield data alone suggest pre-tectonic coalification, but the lack of well-defined reflectance gradients complicates this interpretation. Hydrothermal alteration may have been a significant cause of the coalification in this region. Previous investigations of coals in fault blocks have considered the role of hydrothermal mineralization in coalification. Southern Union and Webster counties are adjacent to the Fluorspar District, a region of extensive hydrothermal metamorphism. It is possible that convective heat transfer related to Fluorspar District mineralization led to vertical heterogeneity in the temperature profile and consequent metamorphic history. In Henderson County, north of the Rough Creek fault zone, coal rank is significantly lower, as low as 0.42% Rmax for the Springfield coal. Reflectance gradients are, again, poorly defined. Extensive oil and gas development has occurred in the high volatile C bituminous region to the north of the Rough Creek fault zone, whereas fewer pools, with lower production, are known within the Webster syncline to the south of the fault zone. The rank of the Middle Pennsylvanian coals can be used to estimate the level of maturation of the Devonian New Albany shale, a likely source rock for much of the oil and gas in the coalfield. Previous studies on the maturation of the New Albany shale, which lies about 1 km below the Springfield coal, indicate an equivalent medium volatile bituminous (1.0-1.2% Rm) rank in the Fluorspar District. New Albany rank decreases to an equivalent high volatile B/C (0.60% Rm) north of the Rough Creek fault zone. The significance of the New Albany reflectances is dependent on the level of suppression of vitrinite reflectance in organic-rich shales. The existence of reflectance suppression would imply that the shales could be more mature than studies to date have indicated. It is possible that the episodes of basin dewatering which influenced the coal rank south of the Rough Creek fault zone also flushed the potential oil reservoirs in the same region.

Chemico-petrographic studies of some lignite core samples from Kalol oilfield, Cambay Basin, Gujarat, Western India

The Kalol oilfield in the Cambay graben, Gujarat. western India, is known to contain thick seams of lignite in the Kalol Formation (Middle Eocene), overlying the oil-bearing Cambay Black Shale (Lower Eocene), at depths between 1110 m and 1500 m. The Kalol Formation occurs in the northern portion of the Cambay Basin as a wedge-shaped sequence of regressive and transgressive marine environments, the lignite being confined to the former phase. Chemically, the Kalol lignite is characteristically low in moisture (4.45–4.64%), quite low in ash (1.67-10.82%) and high in volatiles (43.56–55.25%). C is 72.39–77.18%, H is 4.47–5.93%, N is 1.16–1.58%, O is 15.73–18.62%, and S is 0.32–0.86%. According to Seyler's classification, the Kalol lignite can be classified as belonging to rank (a) lower than lignitous, (b) perlignitous, (c) ortholignitous, (d) metalignitous, and (e) bituminous. According to North American (ASTM) classification, utilising data on volatiles and R m oil, the lignite belongs to lignite, sub-bituminous C and low volatile bituminous rank. Petrographically, the Kalol lignite is composed of huminite (50–81%), liptinite (1–16%), and inertinite (6–32%). Inertinite comprises mainly sclerotinite as plectenchyma, fusinite being absent. Exsudatinite is quite common. On the basis of microlithotype, the lignite comprises textile (1–13%), detrite (19–69%), liptitextite (1–10%), liptidetrite (4–16%), inertidetrite (1–25%), detrinertite (3–21%), and inertite (5–26%), with shale (5–12%). R m oil varies from 0.30 to 0.40. The bituminous coal sample is high in shaly matter (53%) and composed of vitrinite (16%) and sclerotinite (29%), the former showing R m 1.80. These studies indicate that the chemical and petrographic constitution of the lignite is favourable for underground gasification.

Pitch and petroleum coke additions to coke oven charges

AbstractSeveral pitch materials and a petroleum coke were added to coke oven charges in an attempt to make good metallurgical coke from Canadian coal of poor coking quality. Coal and petroleum pitches were added to a low fluid western Canadian coal of medium volatile bituminous rank, and the blends coked in a technical‐scale moveable wall test oven having a 230‐kg charge capacity. Pitches improved coke tumble test indices, the principal coke quality parameter related to blast furnace performance. Varying levels of petroleum coke were added to an eastern Canadian coal of high volatile bituminous rank, and the blends, some partially briquetted, were carbonized in a test oven. Tumble indices of coke from the partially briquetted charges approached an acceptable level. These investigations confirm that petroleum products as well as coal derivative can play a useful part in the production of a metallurgical strength coke from poor or non‐coking coals.

The Influence of the Properties of Coals on Their Conversion into Clean Fuels

Abstract Two fundamental controlling factors in the geological histories of coals have determined their physical and chemical characteristics and, consequently, the industrial uses to which they can be put. The first of these is the set of conditions that existed in the original peat swamp, involving the type of vegetation, the nature and extent of the degxadative, preservational, and sedimentary processes, and resulting in varying assemblages of organic macerals and inorganic minerals. Certain of these ingredients are beneficial in conversion processes. The second factor is the nature and degree of the metamorphic changes that the peat deposit underwent during burial within the earth's crust. Although coals of lower rank are readily converted into liquid fuels, the highest yields are obtained from coals of high volatile bituminous rank. Microscopic methods of measuring the contribution made by both of the controlling factors (petrographic type and rank) enable workers to compare the conversion potential ...

Petrology of Talcher coals

A detailed study of the microstructure and composition of lower Gondwana coals of the Barakar stage (Permian) of the Talcher field, Orissa, India, shows them to be noncoking to feebly coking, high- volatile bituminousrank, indistinctly banded coals composed mainly of durain with subordinate vitrain and fusain.