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Date submitted2024-04-25
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Date accepted2024-09-24
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Date published2024-11-12
Specific features of kinetics of thermal transformation of organic matter in Bazhenov and Domanik source rocks based on results of pyrolysis gas chromatography
Pyrolysis of organic matter with subsequent analysis of hydrocarbon composition of the resulting products allows obtaining multicomponent distribution spectra of the generation potential by the activation energies of reactions of kerogen transformation into hydrocarbons. Configuration of the spectra depends on the structure of kerogen and is individual for each type of organic matter. Studies of kerogen kinetics showed that the distribution of activation energies is unique for each oil source rocks. The kinetic model of thermal decomposition of kerogen of the same type, for example, marine planktonic (type II), can differ significantly in different sedimentary basins due to the multivariate relationship of chemical bonds and their reaction energy threshold. The developed method for calculating multicomponent kinetic spectra (four-component models are used) based on results of pyrolysis gas chromatography allows obtaining one of the most important elements of modelling the history of oil and gas generation in geological basins. Kinetic parameters of organic matter of oil and gas source rocks influence the onset time of generation and directly reflect differences in the composition and structure of different types of kerogens. The results of determining the kinetic parameters of two high-carbon source rocks occurring across the territory of three oil and gas basins are shown. Generation and updating of the data of kinetic models of certain oil and gas source rocks will increase the reliability of forecasting oil and gas potential using the basin modelling method.
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Date submitted2023-05-17
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Date accepted2023-08-17
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Date published2023-10-27
Scientific and technical substantiation of the possibility for the organization of needle coke production in Russia
Russia is one of the world's leading steel producers, while about 33 % of production comes from the scrap remelted in arc steelmaking furnaces. The graphitized electrodes of SHP and UHP grades, mainly consisting of needle coke, are used for high current loads and temperatures in furnaces. USA, Japan, Korea, and China are focused on needle coke production, where coal (tar and pitch) and petroleum (decantoil), by-products of metallurgical factories and oil refineries, are used as raw materials. Russia's annual demand for needle coke is approximately 100 thousand tons, but all of it is covered by imports. Russia's raw material potential, established by the authors of the article, is more than 5 million tons per year and includes decantoil, coal tar and pitch, and heavy pyrolysis tar. The results of obtaining needle coke from decantoil and heavy pyrolysis tar are given below. The prototypes of needle coke were produced on specially designed delayed coking laboratory units (loading up to 0.25 and 80 kg). Raw materials were modified according to the original technology of Saint Petersburg Mining University, the convergence of target properties of which is confirmed by the results of quality analysis of the obtained needle coke, including after 100-fold scaling. The electrodes were molded from the obtained coke. After standardized stages of firing, mechanical processing and graphitization at 2,800-3,000 °C, the coefficient of linear thermal expansion was less than 1 × 10–6 К–1, and the value of specific electrical resistance was 7.1-7.4 μOhm, which proves that the obtained carbon material corresponds in quality to Japanese analogues and Super Premium needle coke.
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Date submitted2018-09-07
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Date accepted2018-11-08
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Date published2019-02-22
Assessment of refractory gold-bearing ores based on interpretation of thermal analysis data
- Authors:
- T. N. Aleksandrova
- G. Heide
- A. V. Afanasova
The article presents the results of a study on the possibility to assess refractory gold-bearing ores using thermal analysis data. It studies the flotation concentrates obtained during the enrichment of double refractory sulfide gold-bearing ores. This type of ore is complicated by the fine impregnation of gold in sulphide minerals and the presence of sorption-active scattered carbonaceous matter, which is in close association with sulphides. The results of thermogravimetric and mass spectrometric studies of refractory gold-bearing ores are presented. The obtained fragments for kerogen CH (m/z = 15), C 2 H (m/z = 29) and C 3 H (m/z = 43) indicate the presence of various types of carbonaceous matter in the studied samples. It is justified that the degree of sorption activity of carbonaceous matter depends on the presence of kerogen and bitumen in the ore. High sorption activity of scattered carbonaceous material significantly affects the processing technology of ores and concentrates, both flotation and pyro- and hydrometallurgical methods. Thermogravimetric and mass spectroscopic analyzes can be used to determine the degree of preg-robbing of refractory gold-bearing ores. The obtained results predetermine the direction of creating new methods and technologies in the field of decarburization of refractory gold-bearing ores in the integrated development of solid minerals in the mining regions of Russia.
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Date submitted2015-07-16
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Date accepted2015-09-28
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Date published2016-02-24
Examination of the raw materials and the products of the combustible shales processing
- Authors:
- N. K. Kondrasheva
- S. N. Saltykova
The reserves of combustible slates of Russia in shale oil and gas equivalent are more than the reserves of oil and natural gas. The formation of a large volume of ash is a major problem connected to the processing and the usage of the combustible slates. It is possible to look at this problem from a different angle of vision if a mineral part of slates is considered as a complex organo-mineral raw material where a mineral substance of the slates is the same raw material as the organic one. For this purpose, it is required to study in detail the physicochemical characteristics of the combustible slates and the behavior of the organic and the mineral parts of the slates during the heat treatment. This research focuses on the phase composition of Leningrad fuel shale and its changes on pyrolysis. They were studying the phase composition, the gas phase outlet, pyrolysis mass balance of combustible slates in the nitrogen atmosphere in the temperature range of 200-1000 °С, the porosity changes of combustible slate in the nitrogen atmosphere in the temperature range of 25-900 °С. It is determined that the main minerals of combustible slates are calcite (28 %), quartz (25 %), illite (17 %), and microcline (11 %). The temperature dependence of the shale porosity is studied in a nitrogen atmosphere and in air. The porosity changes in four stages: (I) 25-200 °C; (II) 200-400 °C; (III) 400-600 °C; (IV) 600-900 °C. The mass balance pyrolysis of combustible slates in a PTK_1.2_40 tube furnace is made up, in the nitrogen atmosphere of 200, 400, 600, 800 and 1000 °C.