Forecasting of industrial coke quality at JSC EVRAZ NTMK based on data of passive industrial experiment. Report 1. Forecasting of CSR and CRI of industrial coke

A forecast of coke quality takes a special place in the coke production, since it enables to increase efficiency of management of batching process of various by composition and properties coals and production of coke of stably high and required quality with minimal costs. Description of a methodological approach to processing of passive industrial experiment data of blends coking at Coke production department of JSC EVRAZ NTMK presented by application selective (general) matrix. The matrix accounts various multilevel values of influence factor CSR and CRI of coke - a complex index of coking ability of blends K.п.к.Vo. It was shown that the proposed approach provides wide variations of response function (CSR/CRI) at symmetrical enough matrix, excluding predominance of any particular area of values of indices K.п.к.Vo and CSR/CRI. By applying the passive industrial experiment, based on processing of actual report data of industrial blends coking at the coke batteries No. 5-6 (wet quenching) and No. 9-10 (dry quenching) by selective matrix, mathematical models of forecast of quality of industrial coke by wet and dry quenching (CSR/CRI) were elaborated depending on coal charges properties (K.п.к.Vo) at the existing modes of their preparation and coking at the coke batteries No. 5-6 and 9-10. Verification of accuracy of the mathematical models of coke quality forecast at wet and dry quenching (CSR/CRI) processing a large actual material of industrial coking (62 coking operations in the coke batteries No. 5-6 and 58 coking operations in the coke batteries No. 9-10 showed accuracy good enough for practical application of forecasting indices CSR and CRI of industrial coke of wet and dry quenching.

SUBECONOMIZER FOR IMPROVENT OF ENERGY EFFICIENCY OF CDQ PLANT MODULE

The article is devoted to the adjustment of the efficiency of the coke dry quenching plant (CDQP) by installing the subeconomizer in the technological scheme of coke production. A work description is presented of the subeconomizers and analyzes the advantages of the subeconomizers on the existing and new CDQP blocks. It has been emphasized that in coke production one of the most important factors is the need to work all parts of the technological chain with the full productivity. Decreased productivity or disruptions in certain areas can lead to significant losses of the final product. It is shown that the dry coke quenching plant should ensure not only stable operation of the coke battery, but also the required level of coke supply for blast furnace production. Therefore, violation of the technological regime of DCQP can critically affect the production of iron and steel. The feature of dry coke quenching technology is emphasized: the increase in productivity inevitably causes an increase of the temperature of quenched coke. It is shown that one of the ways to maintain the temperature of the quenched coke at the required level is to install a subeconomizer (SE) in the scheme of DCQP. The experience of SE "GIPROKOKS" in designing the reconstruction of existing DCQP is underlined. Data on the operation of the DCQP with the SE included in the technological scheme (which has been successfully operated for more than three years) and without it are given. SE "GIPROKOKS" studies, develops and implements new technologies that can be used in the construction of new coke plants, as well as in the reconstruction of existing ones. It is shown that the use of subeconomizers in dry coke quenching plants allows to increase the productivity of DCQP units on quenched coke by about 10 % while maintaining the required temperature and quality of the obtained coke. Keywords: dry coke quenching, temperature of quenched coke, coke yield, subeconomizer, energy efficiency. Corresponding author S.Yu. Abdullin, е-mail: [email protected]

Technological modes of efficient metallization of iron-oxide-containing waste from metallurgical production

During the research, rolled scale and gas cleaning slimes from oxygen-converter workshop No. 1 of JSC “EVRAZ ZSMK” were used as iron-oxide-containing materials. Semi-coke from brown coals of the Berezovskoye deposit of the Kansko-Achinsk basin (temperature of semi-coking is 750 °C), coke fines of PJSC “Coke” and dust from coke dry-quenching plant of JSC “EVRAZ ZSMK” were used as carbon reducing agents. Total iron, FeO and Fe2 O 3 oxides amount to 73.3, 75.5 and 20.9 % in scale, 41.2, 4.7 and 53.7 % in sludge, respectively. Sludge also contains 4.3 % of total carbon and 20.6 % of CaO. Brown-coal semi-coke, coke fines and coke dust contains carbon and volatiles 94.05 and 9.5 %, 97.50 and 2.1 %, 97.47 and 1.6 % on dry ashless weight, respectively. For metallization of furnace charges with composition: scale, slime–semi-coke, coke fines, dust with addition of 10 % water-soluble binding–molasses, strong unroasted briquettes were pressed. Metallization modes of analyzed charge compositions were thermodynamically predicted and technologically determined. Metallization degree and metal iron content at usage of brown-coal semi-coke were found to be 97.5 and 90.2 % for scale, 97.5 and 71.3 % for sludge; of coke fines: 70.7 and 61.9 % for scale, 68.9 and 48.4 % for sludge; of coke dust: 72.1 and 62.6 % for scale, 69.2 and 48.2 % for sludge. The possibility of achievement the metallization degree of 97.0 – 98.0 % was established for briquetted charge from scale – brown-coal semi-coke with 92.0 – 93.0 % of total iron, 89.8 – 90.6 % of metallic iron, 2.8 – 3.2 % of FeO, 0.06 – 0.08 % of S, 0.016 – 0.018 % of P, 1.7 – 1.9 % of C, 1.0 – 1.2 % of CaO and 0.25 – 0.35 % of MgO at 1173 K and duration of 40 min.