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Carbonaceous fuels, their properties and testing
Published in Jaroslav Legemza, Mária Fröhlichová, Róbert Findorák, Biomass and Carbon Fuels in Metallurgy, 2019
Jaroslav Legemza, Mária Fröhlichová, Róbert Findorák
Why is it important to study and analyse maceral composition? Why is it necessary to know the structural composition of coal? Is the basic chemical analysis of carbonaceous fuels not sufficient? We can find the answer to these questions only if we understand the relationship between the structure (microtexture) and physical-chemical properties of carbonaceous fuels. Reactivity is one of the most important properties of coal and coke used in metallurgical processes. Different reactivity of carbonaceous fuels is required for various metallurgical processes. For instance, blast furnace coke should be less reactive, while the coke for ferroalloy production should be as reactive as possible. In general, the reactivity of coal and coke decreases with the increasing degree of coalification of coal. In terms of maceral composition of coal, vitrinite is the active maceral in coal, while inertinite is the inactive one. Microtexture of coal and coke affects primarily their reactivity. Coarse anisotropic components (optically active component with a greater surface area) are less sensitive to the oxidation reaction and temperature shocks than fine anisotropic and isotropic components. This knowledge is also used in the evaluation of carbonaceous fuels in their metallurgical application. Tab. 10 shows a generalised influence of the structure on the reactivity of coal, which has been discussed above [31].
Petroleum Origin and Generation
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Kerogen is closely related to coal. Coal consists of three types of distinct microscopic organic units called macerals along with inorganic materials. ‘Maceral’ particles are the building block of coal similar to ‘mineral’ particles in rock. A maceral group of coal which is also found in kerogen consists of three constituents: liptinite, vitrinite and inertinite macerals. All three maceral groups have sub-groups as well. On the basis of hydrogen content, atomic H/C and O/C ratios and maceral group, kerogen is classified into four generic types as shown in Table 2.2.
Complex use of coal of Northern part of Donbass
Published in Genadiy Pivnyak, Volodymyr Bondarenko, Iryna Kovalevs’ka, Mykhaylo Illiashov, Mining of Mineral Deposits, 2013
V. Savchuk, V. Prykhodchenko, V. Buzylo, D. Prykhodchenko, V. Tykhonenko
According to the source material, coal of northern boarders of Donbass belongs to humus group. Quite rarely coal layers contain sapropelite-humites in the form of narrow bands. In general, coal is the complex mixture of macerals of the groups of vitrinite, inertinite, and leptynite. Each maceral is available according to the standard (Savchuk 2011).
A new equation for the prediction of coal self-heating based on maceral content
Published in International Journal of Coal Preparation and Utilization, 2022
Amir Saffari, Mohammad Ataei, Farhang Sereshki
The spontaneous coal combustion tendency was related to the maceral content, resulting in the following main conclusions: The spontaneous coal combustion tendency was influenced by the vitrinite, and liptinite contents, and had an influence on the R70 values; spontaneous coal combustion was accelerated with an increase in these characteristics.The inertinite content had an inverse relationship with the spontaneous coal combustion tendency, and spontaneous coal combustion decreases with an increase in this characteristic.
Microbial desulphurisation of coal: a review
Published in International Journal of Sustainable Energy, 2023
Cemil Koyunoğlu, Hüseyin Karaca
Inertinite maceral group is formed as a result of chemical reaction with oxidation of cellulosic structure in coal. Although it is an aromatic structure with low volatile matter and hydrogen in structure, it has a high carbon content. During combustion, active molecules with different characters are produced depending on the coal grade and the type of inertinite (Yao and Liu 2019; Ahamed et al. 2019; Dai, Bechtel, et al. 2020; Dai, Hower, et al. 2020; Li et al. 2019; Moldoveanu 2021; Pashin et al. 2020; Sen and Dash 2020; Tangstad et al. 2019; Valentim 2020).
Evaluation effect of macerals petrographic and pyrite contents on spontaneous coal combustion in Tabas Parvadeh and Eastern Alborz coal mines in Iran
Published in International Journal of Coal Preparation and Utilization, 2022
Amir Saffari, Farhang Sereshki, Mohammad Ataei
An organized experimental study was carried out for finding the spontaneous coal combustion tendency by collecting coal samples from two coal fields in Iran. The spontaneous coal combustion tendency was related to the coal petrography, resulting in the following main conclusions: The spontaneous coal combustion tendency was influenced by the pyrite, vitrinite, and liptinite contents, and had an influence on the CPT values; spontaneous coal combustion was accelerated with an increase in these characteristics.The inertinite content had an inverse relationship with the spontaneous coal combustion tendency, and spontaneous coal combustion decreases with an increase in this characteristic.The liptinite and pyrite content levels in the Tabas Parvadeh coal mine samples were greater than those in the Eastern Alborz coal mine samples.The inertinite level was higher in the Eastern Alborz coal mine samples.The mean CPT value was 148.43ºC in the Tabas Parvadeh coal mines and 175.86ºC in the Eastern Alborz coal mines. Thus, the Tabas Parvadeh coal mine samples had a higher potential for spontaneous combustion.The CPT value trend in the Tabas Parvadeh coal mines had a sharper slope variation.The increase in the liptinite and pyrite contents and a decrease in the inertinite content in the Tabas Parvadeh coal mines have contributed to the tendency for spontaneous coal combustion.