EFFECTS OF TECHNOLOGICAL PARAMETERS ON BARZAS COALS THERMAL CONVERSIONS IN VARIOUS MEDIA

Abstract

The relevance of the study is related to the prospects for deep processing of solid fuel and the need to obtain more detailed information about the basic laws of thermal transformations of coal during its liquefaction. The development and improvement of direct coal liquefaction technologies in the future can become an important source of additional hydrocarbon resources for the chemical industry and power engineering. The main aim of the research is to study the effects of technological parameters (temperature and pressure) on liquefaction and thermal transformations of Barzas coals in carbon dioxide and hydrogen atmospheres in order to establish the relationships between thermal treatment conditions of coal feedstocks and the compositions and yields of its conversion products. Objects: sapromixites of the Barzas coal deposit (Kemerovo region, Russia) and products of their thermal transformations in carbon dioxide and hydrogen media. Methods: heat treatment of the coals studied in a laboratory microautoclave in various media (CO2, H2) and analysis of the products of their transformations by elemental analysis (CHNOS), FTIR spectroscopy and mass spectrometry. The studies were carried out on calibrated and serviceable equipment. The list of equipment and methods used in the given work are described in detail in the experimental part of this article. Results. Almost similar temperature and pressure dependences (extremal type curves) have been revealed for both the changes in the IR absorption intensities of alkyl groups and the yields of «coal liquids» (total amounts of maltenes and asphaltenes) in the process of Barzas coals transformations in carbon dioxide and hydrogen media. Differences in the transformations of two modifications of Barzas sapromixites were established, and a predominantly paraffin-naphthenic character of the functional composition of the resulting «coal liquids» was revealed. A clear relationship was found between the yields of gaseous products and atomic ratios H/C in the solid products of transformations of the Barzas sapromixites. «Coal liquids» and gaseous compounds obtained as a result of Barzas coals thermal processing can serve as potential raw materials for production of hydrocarbons and other valuable chemical products, as well as used as a fuel in production of heat and electricity.

Keywords

• barzas coals
• thermal treatment
• temperature
• pressure
• carbon dioxide
• hydrogen
• «coal liquids»
• h/c atomic ratio