Work number - M 11 AWARDED
Presented by the National Technical University "Kharkiv Polytechnic Institute"
Author: Miroshnichenko D.V., ScD
The aim of the work is to solve an important scientific and technical problem: on the basis of expanding scientific concepts on the process of oxidation of coking coals of various degrees of metamorphism and studying the change in their properties during storage and preparation for coking, develop scientifically grounded recommendations on the rational usingof oxidized coals for the production of blast furnace coke.
It has been established that the process of oxidation of coking coal, regardless of the degree of their metamorphism (Vdaf=19.9–39.3%), granulometric composition (0–200 mm), oxidation temperature (-12 ... + 140 оС) and duration of oxidation (up to 200 days) consists of three main stages: initial, intense oxidation and saturation, which are characterized by different values of the rate constants of the oxidation process.
It is determined that the process of natural oxidation of coals when stored in pilesof an open warehouse during the summer and winter periods at a temperature of -12 to +33 oC is described by the exponential equation of the heterogeneous Avrami-Erofeev reactions. The minimum values of the rate constant of the oxidation process (0.0197∙10-4 min-1 in summer and 0.0073∙10-4 min-1 in winter) characterize the coals of the middle stage of metamorphism (Vdaf=25–30%).
For the first time it has been proved that the coals of the middle stage of metamorphism at the initial stage of oxidation improve their coking ability in terms of the mechanical strength of the obtained coke. A hypothesis has been formulated and experimentally confirmed that the improvement in the coking ability of coals of the middle stage of metamorphism during partial oxidation is due to an increase in the viscosity of the plastic mass formed by the oxidized coal, as well as an increase in the volume of degradation products, which leads to an increase in intra-plastic pressure and expance pressure. Developed, approved UNPA "Ukrkoks" and transferred to the coke-chemical enterprises of Ukraine "Methodological recommendations on the usingof oxidized coals in the production of blast furnace coke." The main partsof the "Methodological Recommendations ..." are included in the Rules for Technical Operation of Coke Chemical Enterprises of Ukraine.
61 works have been published on the topic of the work, including 41 articles in specialized scientific journals (23 of which are in Scopus), 13 abstracts in the proceedings of international conferences, 2 chapters in the Coke Handbook, 2 Ukrainian patents and 3 DSTU. According to the Scopus database, the total number of links to the author's publications is 145, the h-index is 7; according to the Google Scholar database, the total number of links to the author's publications is 292, the h-index is 8. There are 1 doctoral and 2 candidate dissertations defended on this topic.