Simulation of coking in coke furnaces

Computer simulation of the coking process in coke furnaces provides information regarding the yield and quality of the coking products as a function of the temperature and the yield of volatiles from the batch. The simulation includes calculation of the temperature in the heating channel from the nonsteady heat-conduction equation of the coal bed in the furnace chamber of a coke battery; the material balance of coking; the thermal balance; and the hydraulic conditions in the coke furnaces.     

Hydraulic and Thermal Regulation of Coke Batteries with Unidirectional Gas Input and Product Output

The problems arising in the operation of coke battery 3 at Rourkela Steel Plant (India) are considered. The design of coke battery 3 is described. It has an Otto system; the capacity of a single coking chamber is 21.6 m³. Hybrid heating is employed, and heating gas is supplied to the bottom of the chamber. A method is proposed for hydraulic regulation of the coke battery with unidirectional heating-gas input and product output.     

Cleaning the inclined flues in coke batteries with bottom heating-gas supply

Operational problems at coke battery 6 of Rourkela Steel Plant in India are considered. The structure of coke battery 6 of PVR type (useful capacity of the coke ovens 41.6 m³) is described; it is characterized by bottom supply of the heating gas and hybrid heating. Removing the scale buildup from the inclined section of the heating channels improves the thermal and hydraulic conditions, extends coke-battery life, and eliminates nonuniform heating of the coke cake.     

焦炉烟囱NOx排放控制刍议

新的国家标准《炼焦化学工业污染物排放标准》提出了焦炉烟囱的NOx排放控制要求。本文从焦炉加热系统的设计和对焦炉烟道废气的后处理2个层面论述了焦炉烟囱NOx排放控制的技术措施,简要介绍了SCR烟气脱硝技术,提出了借鉴日本东京煤气公司的中试与工程经验,采用SCR脱硝技术对焦炉烟道废气进行后处理,以达到国家标准对“特别地区”焦炉烟囱的NOx排放控制要求。     

Design and construction of coke battery 1A at Radlin coke plant,Poland

In the design and construction of coke battery 1A at Radlin coke plant (Poland), coking of rammed coke with a stationary system was employed for the first time. The coke batteries are grouped in blocks. Safety railings are provided on the coke and machine sides of the maintenance areas.     

Coke battery with 51-m<Superscript>3</Superscript> furnace chambers and lateral supply of mixed gas

The basic approaches employed in the construction of coke battery 11A at OAO Magnitogorskii Metallurgicheskii Kombinat are outlined. This battery includes 51.0-m³ furnaces and a dust-free coke-supply system designed by Giprokoks with lateral gas supply; it is heated exclusively by low-calorific mixed gas consisting of blast-furnace gas with added coke-oven gas. The 82 furnaces in the coke battery are divided into two blocks of 41. The gross coke output of the battery (6% moisture content) is 1140000 t/yr.     

加强焦炉生产管理 提高焦炭机械强度

炼焦生产工艺管理如加热制度、装平煤操作会影响焦炭的机械强度,只有通过不断加强炼焦的生产管理才能提高焦炭质量。     

Adding coke dust to coal batch

The granulometric composition of coke dust from the dry-slaking machine is determined. The influence of additions of 3−7% coke dust on the quality of industrial coking batch and the coke obtained by box coking is estimated. Adding 1% coke dust to coking batch does not markedly change the coke quality. Industrial equipment for the supply of dry-slaking dust to the batch is described.     

大型焦炉荒煤气导出和外逸状况的剖析

根据荒煤气导出的影响因素,介绍了大型焦炉荒煤气导出使用的3种装置,同时分析了大型焦炉在结焦过程中和装煤操作时荒煤气的外逸状况。     

关于捣固炼焦焦饼收缩度的探讨

分析了捣固炼焦与顶装炼焦的焦饼收缩度差异性及其影响因素,探讨了低挥发分配煤在捣固炼焦设计和生产等方面的问题,并提出了下列措施:适当降低加热水平;设定合理的结焦时间;设计可调煤饼宽度的装煤车;根据配合煤Vdaf和X值调整煤饼宽度、高度及采用XD值指导生产,以保证煤饼与炉墙有足够的间隙和适宜的空间温度。     

Propane-butane heating of coke batteries

Experience has been gained in propane-butane heating of the first coke batteries of a newly constructed coke plant, where no coke-oven gas or blast-furnace gas is available. Under the guidance of specialists at ZAO Ogneuporkoksservis (OKOS), five coke batteries have been successfully heated and put into operation. For the first time in global practice, a coke battery has been converted to continuous propane-butane heating. Propane-butane heating of the coke battery has been tested and confirmed as a reliable means of preparing the first batteries at a newly constructed coke plant for startup and production. In addition, experience shows that continuous propane-butane heating is possible for a battery with a limited supply of coke-oven gas for heating.     

5.5m捣固焦炉结焦时间对焦炭质量的影响

通过5.5m捣固焦炉结焦时间的改变,探讨了在配煤比不变的条件下结焦时间变化对焦炭质量的影响。结果表明,适当延长结焦时间能有效提高焦炭的抗碎强度和反应后强度,改善焦炭的耐磨强度和反应性,有效降低焦炭硫分,而且能够配入更多的弱黏结煤,降低入炉煤成本。     

评价两种原料油生产针状焦的可行性

通过试验评价了1#和2#两种原料油作为针状焦原料的可行性,结果表明,1#原料油不适合作为生产针状焦的原料,2#原料油适合作为生产针状焦的原料。实验考察了焦化过程中温度、压力、成焦时间对焦炭质量的影响。结果表明2#原料油在实验室生成针状焦的适宜温度为480~500℃,适宜的压力为先加压至2 MPa然后减压至1 MPa,最佳成焦时间为7 h;同时考察了煅烧过程中煅烧温度、升温速率和煅烧时间对煅后焦质量的影响。     

Determining the air excess in the heating of coke furnaces. 3. Calculation of the air excess

The chemical mechanism by which coke-oven gas burns in the heating ducts of coke ovens is considered. A formula is obtained for the air excess. In contrast to the existing formula, the proposed version takes account of not only the content of oxygen, carbon monoxide, and carbon dioxide in the combustion products but also the content of sulfur dioxide, hydrogen, methane, nitrogen oxides. Analysis of the combustion products in the heating ducts of a coke battery with 30.9-m³ ovens shows that the content of incombustible components in the coke-oven gas may reach 3%. Calculation of the air excess by means of the proposed formula permits improvement in the uniformity of the temperature distribution in the heating system, the prevention of specific lining defects, and decrease in atmospheric emissions when the coke battery is heated by means of coke-oven gas. The proposed method of determining the air excess may be used not only in equipment for coke production but also in other metallurgical systems where coke-oven gas is burned.     

炼焦机理和焦炭质量预测的研究进展

综述了煤的热塑性、炼焦机理和焦炭质量预测的研究进展。煤的化学结构如煤中镜质组的烷基侧链和移动氢的含量决定了煤的热塑性,核磁共振、质子磁共振热分析、拉曼光谱和电子顺磁共振谱等从分子水平解释煤的热塑性、配合煤的相互作用和炼焦机理。塑性成焦机理认为,良好的氢传递和分子重排是炼焦中获得优质焦炭的重要条件,塑性成分在焦炭光学组织形成中非常关键,改变加热速率可使煤的光学组织形成机理改变。碱度指数（modified basicity index,MBI）、复合焦势（composite coking potential,CCP）和组合煤指数（combined coal index,CCI）等参数可精确地预测焦炭反应后强度和焦炭反应性。矿物质对焦炭强度的影响是研究热点,控制焦炭的裂纹和尺寸是未来焦炭质量的要求。     

焦炉立火道温度变化规律的探讨

分析了立火道温度的分布规律,分析表明,立火道温度是加热煤气流量和两侧炭化室吸收热量共同决定的。对于5-2串序操作的焦炉,立火道温度的最低点在装煤后约5h闷炉后且另一侧炭化室的焦炭接近成熟的时刻。立火道温度的最高点在两侧的炭化室推焦前后。     

Experience with coke battery 3 at OAO Koks

Experience with a coke battery containing coke ovens (height 6.7 m) with lateral supply of heating gas is outlined. Means of eliminating the deficiencies discovered in debugging the coke battery are discussed.     

煤在炼焦过程中热解脱硫降低焦炭中硫含量

通过模拟工业焦化过程,针对一种高硫煤考察了不同气体种类、流量及加热速率下,焦炉煤气返回焦化过程对物焦炭中硫含量变化的影响。结果表明,焦化过程中通入H2,CH4和N2气体可以抑制热解气中的硫返回固体焦炭中,H2达到的焦炭脱硫量最大,其次是CH4和N2;增大气体流量、减小加热速率有利于使硫向气相转移,从而使固体焦炭中的硫分配降低;固体焦炭中硫含量变化亦表明,H2效果较佳,在3．0,1．5℃／min2种加热速率下可使焦炭中硫含量分别降低0．36％～0．39％和0．46％～0．56％。     

129Xe-NMR study of coke distribution in dealuminated HY zeolites

Zeolites coking has been studied by¹²⁹Xe-NMR technique. The distribution of the coke is heterogeneous on the supercage surface at low cokage level. When coking increases up to 10% the supercages are lined with coke and the residual internal volume consists of narrow channels. Beyond 10% the coke also affects the external surface of the zeolites, with the formation of coke microcavities between the crystallites. This technique has also enabled us to show the role of extra-framework Al in the cracking activity of zeolites.     

Oxidation of coke with petroleum-based coking additives

The properties of coking batch may be stabilized by means of DK coking additive based on the products of petroleum pyrolysis, characterized by low ash content (A^d = 0.4%), high sulfur content (S_t^d= 4.1%), and high yield of volatiles (V^daf = 17.2%) relative to coal concentrates. Individual coking of DK coking additive yields a product (particle size >40 mm) with postreactive strength CSR = 77–79%, reactivity CRI = 18–22%, and density 1200–1400 kg/m³. Differential scanning calorimetry of experimental coke samples reveals six stages in their heat treatment in air: preliminary heating, intense oxidation, gasification of carbon, surface combustion of the gaseous products, their flare combustion, and oxidation of the residue. The use of DK coking additive in the coking batch shifts the oxidation process to higher temperatures and ensures the largest interval of heat liberation at elevated heating rate, with up to 50% DK additive. With increase in the content of DK additive from 30 to 50%, the activation energy is increased by 4.56 kJ/mol for each additional 10%. In that case, the supply of atmospheric oxygen to the combustion zone must be improved