Industrial experience with the thermal preparation of coal batch before coking

The basic industrial results obtained with thermal preparation of batch, followed by bed coking in horizontal furnaces, are briefly reviewed. Precarbon technology, which, in various forms, has been successfully used for many years, seems promising for the production of high-quality coke in a period of declining batch quality.     

Modified coal batch in coking

The influence of volatile products from low-metamorphic poorly clinkering G coal on plasticmass formation in rammed batch during coking is considered. An experimental batch of modified coke has been produced at PAO Alchevskkoks.     

Optimizing the coal batch for coking

Optimization of coke production is considered. Mathematical experiment design, which is an active research method, calls for artificial changes in the input parameters. In actual production conditions, active experiments are not possible on account of material and time constraints. These problems may be eliminated on the basis of reserves of production data.     

Interaction of low-metamorphic coal components in coking batch

The interaction of low-metamorphic coal components in coking batch during pyrolysis is studied. The characteristics of the resulting coke are presented, and the partial hydrogenation is discussed.     

Improving the preparation of coal batch for coking

Various methods of preparing coal for coking are analyzed. Laboratory experiments are conducted with a view to obtaining higher-quality coke from batch with a high content of poorly clinkering coal.     

低阶烟煤对常规炼焦煤热塑性影响规律研究

为提高低灰低硫低阶煤的配煤炼焦用量,在低阶烟煤煤岩分离的基础上,研究了低阶烟煤镜质组对气煤、肥煤、焦煤等常规炼焦煤塑性胶质体的流动性、膨胀性和黏结能力等影响。结果表明,随着低阶烟煤镜质组比例的增加,气煤、肥煤、焦煤塑性胶质体的流动性、膨胀性和黏结力指数下降。低阶煤镜质组的比例为12%时,所得气煤配低阶煤镜质组的流动性下降70.0%,黏结指数下降31.8%;所得肥煤配低阶煤镜质组的流动性下降66.1%,黏结指数下降9.4%;所得焦煤配低阶煤镜质组的流动性下降78.4%,黏结指数下降45.7%。配入低阶煤镜质组比例为8%时,气煤的膨胀度由1.3%降至-19.5%,肥煤的膨胀度由158.7%降至88.2%,焦煤的膨胀度由28.5%降至-1.2%,呈现劣化作用。所得配煤指标并不存在线性关系,对焦煤影响最大,交互作用偏负;对肥煤影响较小,交互作用偏正。     

Elegest coal in coking batch at OAO EVRAZ ZSMK

The coking of batch with different proportions of Elegest coal from the Ulug-Khemsk Basin is investigated in laboratory and production conditions. The mechanical strength of the coke is improved when such coal is used in the batch. At the same time, CSR falls, while CRI rises.     

Using coke-battery flue gas to dry coal batch before coking

The utilization of heat from coke-battery flue gases and other potential secondary energy resources in drying coal batch prior to coking is considered. The main factors that influence the thermal potential of the flue gases as a drying agent are identified. The reduction in moisture content of the coal batch prior to coking thanks to the coke-battery flue gases is calculated for different battery operating conditions. Technological principles for combining the drying of coal batch with its preparation by selective crushing and pneumomechanical separation are considered.     

Influence of the coking properties of coal batch on coke properties

At OAO Zapadno-Sibirskii Metallurgicheskii Kombinat (ZSMK), research is undertaken to improve the optimization of coking batch. The basic approach, proposed by specialists from OAO Nizhne-tagil’skii Metallurgicheskii Kombinat, employs the coefficient K _opt, which characterizes the deviation of the batch from its optimal composition. The coking properties of the OAO ZSMK coal batch over the last few years are analyzed. After laboratory and industrial coking of batch with different K _opt, the strength and reactivity of the resulting coke is investigated. Evaluation of coke-grade coal in terms of its rank according to State Standard GOST 25543-88 proves inadequate, since coal of the same rank may differ markedly in coking properties. A method is established for assessing the optimality of the coal batch at OAO ZSMK.     

Optimizing the preparation of coal batch for coking at ChAO Makeevkoks

The expediency of introducing up-to-date systems in the preparation of coal batch for coking at ChAO Makeevkoks is evident if the quality of the coal concentrates employed is assessed in terms of technical, plastometric, petrographic, and granulometric characteristics. Coking trials indicate that separating out the small coal classes prior to final crushing significantly improves the technological characteristics (M ₂₅, M ₁₀) and structural parameters (the Ginzburg abrasive hardness and Gryaznov structural strength) of the blastfurnace coke produced. Introducing hydrocarbon briquets in the coal batch permits the utilization of coking waste without impairing the coke strength.     

Preparation of coking batch

With steady decline in quality of the coal available for coking, particular care must be taken in batch preparation. Correct choice of the degree of coal crushing in accordance with the actual proportions of bituminous and coke-grade coal maintains the petrographic composition of the batch and prevents a predominance of lean components.     

Optimizing the composition of coking batch

Theoretical aspects of coking batch formulation and practical experience at OAO Nizhnetagil’skii Metallurgicheskii Kombinat (NTMK) are considered. An integral characteristic, the optimal batch coefficient K _opt, permits ongoing assessment of the batch composition’s optimality and prediction of the coke’s mechanical strength.     

无焦煤炼焦时惰性物对焦炭微观强度的影响

在无焦煤的炼焦条件下,将徐州气煤和枣庄肥煤两种煤混合,以此混煤为基础煤料,添加不同粒度的焦粉、瘦煤、无烟煤进行坩埚焦炼焦实验,对所炼制的坩埚焦进行焦炭光学组织、焦炭显微强度和结构强度分析测试。结果表明,添加惰性物使焦炭的各向异性指数(OTI)增大,I+Mf+FF减小;3种惰性物中,添加焦粉对提高焦炭显微强度和结构强度效果最好;惰性物的粒度越小,提高焦炭质量效果越明显。     

炼焦煤焦化特性评价指标探讨

介绍了奥亚膨胀度、基氏流动度、罗加指数、胶质层指数、黏结指数和镜质组平均最大反射率等冶金煤焦化特性评价指标的建立和测试方法,以及各评价指标在我国的应用情况。同时讨论了各个指标对胶质体的原生黏结性、膨胀程度引起的黏着性和焦炭残留物强度这3个焦化特性的表征。     

Influence of the high content of Zh coal in coking batch on the coke quality

Industrial tests show that the enrichment of coal batch containing more than 70% Zh coal must be increased in order to boost coke strength. However, it makes more sense to replace some of the Zh coal in the batch with an optimal quantity of G coal, and to reduce the degree of crushing, so as to ensure coke quality consistent with blast-furnace requirements (minimum strength M ₂₅ = 90%, M ₁₀ = 6%).     

Influence of petroleum coking additive on the quality of coal batch,coke, and tar

Given the shortage of coal with good coking properties, a petroleum coking additive is introduced in coal batch so as to expand the range of plasticity. This additive improves coke quality in every respect, except the total sulfur content. Measures to reduce the additive’s negative impact on the coal pitch are considered.