Affiliation:
1. Technological institute of State university of economics and technology, Kryvyi Rih
2. Technical University «Metinvest Polytechnic», Zaporizhzhia
Abstract
The methods of managing the quality of pellets due to the management of the bottom and side beds are analyzed. A literature review of existing technologies in this area was carried out and it was shown that this issue is not fully resolved in science. Approximate technologies are studied, their advantages and disadvantages are analyzed. In particular, it is shown that the use of existing technology will require additional burning of pellets in another unit, which is technologically impossible and economically impractical. It is shown that this method can be effective for improving the properties of iron ore products, but is not used in industry due to insufficient justification. A new technology of thermal strengthening of pellets is proposed, which allows to significantly improve their strength during recovery in a blast furnace. Conducted studies on thermal strengthening of pellets in a firing bowl with a diameter of 300 mm and a layer height of 400 mm. The results of the research showed that the specific productivity of the firing unit during heat hardening of raw pellets according to the proposed technology is practically similar to the technological regimes adopted in the operating workshops for the production of pellets. The compressive strength of fired pellets according to the proposed technology and accepted in workshops also practically does not differ. However, the impact strength and abrasion resistance during recovery from a suitable fraction of fired pellets obtained by the proposed technology is significantly better than by the accepted one. It has been proven that the developed technology allows to significantly improve the strength characteristics of fired pellets during the recovery process in the blast furnace, which leads to an improvement in the technical and economic performance of the blast furnace. Implementation of the developed technology in industrial conditions in pellet production shops without reconstruction is quite simple and does not require significant capital investments
Publisher
SHEI Pryazovskyi State Technical University
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