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Date submitted2023-10-28
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Date accepted2024-11-07
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Date published2025-02-25
Radiation characteristics of coals at different stages of metamorphism
The formation of deposits and subsequent metamorphic processes that affect concentrations of radioactive elements in coal can indicate ongoing geological activities, therefore, analyzing trends in the radiation characteristics of coal throughout the metamorphic series is highly relevant. The aim of this work is to experimentally evaluate the radiation characteristics of different coal ranks (metamorphic stages) using thermoluminescent (TL) dosimetry and beta activity measurements, and to identify correlations between these radiation characteristics and data obtained from technical, elemental, and thermogravimetric analyses, as well as mass spectrometric and electron paramagnetic resonance spectroscopy (EPR) measurements. For dosimetric measurements that indirectly characterize the content of radionuclides in coal, a modified dosimetric complex and original soil-equivalent thermoluminescent detectors based on SiO2 were used. The analysis of the obtained results supports the use of TL studies to determine the ash content of coals at low and medium stages of metamorphism (coal rank B→G), while indicating that this method is not feasible for coals at higher stages of metamorphism. The correlation dependencies in the metamorphism series suggest abrupt change in the conditions of coal formation during the time range corresponding to transformation from high to low volatile bituminous coals (coal rank G→Zh→K). These abrupt changes in regional metamorphism conditions (time, temperature, pressure, oxidation-reduction conditions) are confined to the boundary of the Permian and Triassic periods (~250 million years ago), during which both the transformation of existing coal deposits and the formation of new deposits occurred.
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Date submitted2009-09-19
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Date accepted2009-11-15
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Date published2010-06-25
Potassium chloride content in ore and products оf recycling automatic control system
- Authors:
- S. S. Galushkin
- B. A. Vishnyak
- V. N. Smirnov
Potassium chloride percentage in continuous transported ore flows and products of potassium plants recycling automatic control system is offered and described. It differs fundamentally from used before ones at bulk solids containing natural radio-activity elements effective constituents producing and recycling plants. Sensing device is used in this information-measuring system (IMS). It allows to realize automatic control in flows for that instantaneous productivity fluidity in wide limits is resided. Using such IMS gives considerable economic effect by measurements error lowering and their quickness increase.