A technology of production of a high-basic sinter in the agromeration workshop of Enakievo metallurgical plant and possible ways of its improvement

During the last six years production of high-fluxed sinter at sinter workshop of Enakievo metallurgical plant is accomplished by using sinter charge, comprising almost equal shares of iron ore concentrate and metallurgical wastes. It is done because of insufficient and non-regular supplies of iron ore concentrates. The experience gained can be of some interest for specialists of sintering and BF production of other plants to ensure the operation under conditions of breach of iron ore raw material supply as well as utilization of wastes. An analytical and statistical evaluation of technical and economical indices of sintering accomplished, while component content, the charge basicity and technological conditions of it preparation and sintering variation. Results of industrial study of technological conditions and sinter production parameters presented while its basicity was varied within the range of 1.7–4.1 abs. units in some periods of 2019. Results of pilot-industrial experiments on production in the IVQ-2019 of several batches of rather strong sinter highlighted, while their basicity was varied in series from 2.0 to 5.0 abs. units. A method of adjusting of sintering speed of a high-basic charge along the width of sintering machine proposed, comprising a rational forming of the charge layer in the charging funnel and the layer profile with a concave parabola surface form along the sintering machine width. The method comprised also an increase of the charge volume density in the upper elemental layers and particularly – in the peripheral zones of general charge layer at the sintering machines pallets. Description of the charging complex on the sintering machine pallets was given. Scientific and practical recommendations elaborated for modernization the technology and technological equipment for the charge loading on the sintering machine.

Efficiency of injection of natural gas and pulverized coal at ironmaking

The method for calculating indicators of blast furnace smelting with replacement of part of coke with additional fuels has been developed on the basis of full and complex compensation and compensating measures. Efficiency of the use of natural gas and pulverized coal in the blast furnace conditions of the Enakievo Metallurgical Plant was calculated and it has been confirmed as rather high. Increase in the consumption of natural gas from the baseline (71.8 m3/t of iron) to 110 m3/t ensures a corresponding increase in productivity of the blast furnace to 107.6 % and a decrease in the consumption of coke to 417.3 kg/t of iron (–38.4 kg/t, –8.42 %). Replacing natural gas with pulverized coal in the amount of 160 kg/t of iron made it possible to completely remove it from the blast. At the same time, coke consumption decreased to 354.59 kg/t of iron (–101.1 kg/t; –22.18 %). Increasing the consumption of pulverized coal fuel up to 200 kg/t of iron with compensation of the blast temperature of1200 °Cand oxygen of the blast of 25 % provides an increase in the productivity of the blast furnace to 105.8 % and reduction of coke consumption to 303.8 kg/t of iron (–151.9 kg/t, –33.33 %). High efficiency of the use of pulverized coal in conditions of the Enakievo Metallurgical Plant is explained by its lower cost compared to natural gas, high carbon content in coal and a significantly lower effecton the theoretical combustion temperature and other technological parameters.