Production management of tamping coke

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A summary of my work, I hope everyone can discuss it enthusiastically. Summary of discussion on production management of tamping coking process: In order to make full use of coking coal resources, improve coke quality and reduce costs. The rules of tamping and coking production management were summarized in a timely manner, which is conducive to giving full play to the potential of tamping and coking technology. keywords: Tamping coking production management 1. Overview As coal resources become increasingly scarce, the tamping coking process is increasingly favored by coking companies. Under real market conditions, it can optimize the raw material structure, improve coke quality, and reduce coke costs. In order to give full play to the potential of the tamping and coking process, on the basis of understanding and exploring the production and management rules of the tamping and coking process, master the rules and utilization rules to promote a virtuous cycle of coking production. 2. Characteristics of tamping coking production management The advantage of the tamping coking process is that by increasing the bulk density of furnace coal, it is beneficial to increase the amount of weakly caking coal. On the basis of ensuring coke quality, it can expand coal sources and save coking coal resources. Compared with the top-loading coking process, the tamping coking process pays more attention to the lithofacies composition of the blended coal, and the fineness and moisture of the coal blend must be strictly controlled. At the same time, it increases the difficulty of coke oven machinery and equipment and coke oven production management, as well as the pressure on coke oven environmental protection. In addition, it also increases the difficulty of process operation of the gas purification system in chemical production processes. 2.1 Production management of the coal preparation workshop The production management of the coal preparation workshop mainly focuses on coal blending management, coal fineness and moisture control. Under the current market conditions, the phenomenon of coal blending is quite serious. Coal and rock methods can only be used to identify the type and degree of coal blending for households. When blending coal, an appropriate coal blending ratio can only be formulated based on the coal and rock results at each supply point. After repeated industrial tests, it can be put into mass production. For tamping coking, when blending coal, it is required to make every effort to increase the proportion of low-price blended coal, while stably digesting low-price lean coal. This requires coal blending personnel to effectively control the coal and rock results of various coal types. When blending coal, they must strictly follow several principles of coal, rock and coal blending, and control the relatively stable maximum average reflectance of vitrinite, the standard deviation of the vitrinite reflectance distribution map of the matching coal, and the volatile content of the matching coal. Practice has proved that when our unit coke mass M10 is less than 6% and M25 is greater than 90.6%, the maximum average reflectance of vitrinite can fluctuate in the range of 0.9~1.44, the standard deviation of the vitrinite reflectance distribution map of the matched coal can fluctuate in the range of 0.2~0.34, and the volatile content of the matched coal can fluctuate in the range of 24%~30%. Compared with the top-loading process, their fluctuation ranges have been expanded. The fineness of the blended coal affects the contact area of ​​the coal particle interface, especially when there are too many inert substances, which affects the coke quality. Therefore, the fineness affects the blending ratio of lean coal, thereby affecting the cost of the blended coal. However, due to the limitations of equipment capabilities and the impact of operating costs, the fineness should be controlled within a cost-acceptable range. When the fineness is too large, it will be difficult to unload materials from the silo, power consumption will increase, the life of the hammer will be shortened, dust will increase the resistance of the gas recovery system, and the effect of the smoke elimination facilities will be deteriorated. Practice has proved that the fineness of coal blended in our unit is generally controlled at about 80%, which is more effective. After adding lean coal, 1/3 coking coal or gas coal, the hardness of the washed coal increases and the wear of the hammer head accelerates. At this time, it is necessary to pay close attention to the changes in the fineness of the matching coal, and in this case, the fineness needs to be appropriately increased, preferably around 85%, to ensure the strength of the coke. It would be better if hard coal types could be crushed individually or selectively crushed. Generally, coking plants do not have large indoor coal yards and large coal storage bins, nor do they have coal humidity control processes. Such measures to control the moisture content of blended coal are mainly to reduce the moisture content of blended coal by strengthening coal yard management and coal loading control in rainy and snowy weather. ； In other dry weather, external water is added after the pulverizer to stabilize the moisture content of the coal. In small coking plants, due to the small coal yard and fast turnover of coal entering the plant, the water content of the washed coal in the coal yard can meet the production needs, and under normal circumstances there is no need to add external water. Through production practice, it is more appropriate for our unit to control the coal moisture content within the range of 11.0-12.5%. When the moisture content of the blended coal is low, the tamping density will tend to decrease. In severe cases, coal collapse will occur, and the furnace top smoke elimination vehicle may also emit black smoke. When the moisture content of the coal is high, the tamping density will also tend to decrease. In severe cases, the probability of coal collapse is higher, and the furnace top smoke elimination vehicle may also emit yellow smoke. Although tamping coking can increase the proportion of weakly caking coal, when the coke strength requirements are relatively high, especially when the M10 requirement is less than 6%, the proportion of weakly caking coal is also limited. On the premise of stably matching the cost of coal, the coke quality is required to be as stable as possible at the lower limit of the control line, so that the coal rock index, fineness and moisture of the coal are required to be matched according to the actual situation. 2.2 Production management of the coking workshop In the face of the tamping coking process, the tasks that the coking workshop must do are:: How to ensure the normal operation of coke oven tamping machinery and equipment, how to ensure that the height and density of coal cakes are stable and appropriate, how to ensure that there is no or less occurrence of cake collapse, how to ensure the treatment effect of furnace smoke and dust, and how to strengthen the maintenance of coke ovens after top-mounted to side-mounted. The maintenance characteristic of tamping coke oven machinery and equipment is that due to the severe vibration during the tamping process, the fasteners of both mechanical equipment and electrical equipment are easy to loosen. In this way, during the first three months when the equipment is put into use, it is necessary to focus on checking the tightening of each component to avoid the occurrence of a loose screw, which will cause the entire equipment to be paralyzed. Another characteristic is that because coal dust is relatively large, it is easy to accumulate in the operating parts of the equipment, oil leakage points and dead corners. When its amount accumulates to a certain extent, it will affect the operation of mechanical equipment, and in severe cases, it will cause operating accidents. Therefore, it is particularly important here that the equipment shows its true color, no oil stains, and no dust accumulation. Practice tells us about the maintenance of tamping equipment. In addition to requiring employees to operate in strict accordance with the specifications, they are also required to conduct shift inspections of fasteners and ensure that all lubrication points are well lubricated. Mechanical limits and dust accumulation everywhere require extra attention to ensure that the mechanical movement is accurate and in place. In addition, when employees are operating, they need to make sure, confirm, and confirm the frequently moving mechanical parts after each action to avoid the occurrence of vicious operating accidents. The height and density of tamped coal cakes are key aspects of daily production management of coking, which involve coke output, coke quality and the amount of lean coal. It is mainly affected by employee operation and the operating status of the tamping machine. In terms of tamping operations, the main factors are the amount of coal placed in each layer and the number of tamping passes. The best effect is the method of tamping in thin layers and multiple times. However, there is great uncertainty in the operation of employees. In view of this situation, our unit uses the size of the furnace roof space before coke pushing to check the coal loading height, and uses special tools to randomly measure the density of coal cakes during the coal loading process, which has achieved good results. In terms of the operation of the tamping machine, the weight of the hammer rod, the lifting height of the hammer rod, and the verticality of the hammer rod operation all directly affect the solidity of the briquettes. In order to ensure the density of the briquettes, severely worn hammer rods and hammer rods with reduced lifting height need to be replaced in time. Careful maintenance and timely replacement of the guide wheels will help ensure the verticality of the hammer rod operation. There are many factors that cause cake collapse during the production process. When the aspect ratio is fixed, the main influencing factors are:: Coordinate with coal moisture, fineness, viscosity and tamping operation process. Too high or too low moisture content can easily cause the cake to collapse. When the fineness is low, it is easy to cause the cake to collapse. Some types of coal are not easy to break, showing more particulate matter and deviation in surface cohesion. When the amount of these types of coal is too high, it is easy to cause cake collapse. In terms of tamping operations, we must strictly control the amount of coal placed in the first layer of coal and the number of tamping times, which is the basis for whether the entire coal cake is solid or not. For each layer of coal above, it is best to beat thin layers more often, and consciously extend the pounding time at both ends of the coal box, so that the coal cakes that come out are solid and stable enough. Generally, skilled workers are required to select different amounts of coal and the number of tamping passes based on the moisture, fineness, and viscosity of the coal. Cake collapse can easily cause local high temperatures on the coke oven wall, and in severe cases can lead to damage to the oven wall. The collapse of the coke side cake can easily lead to the failure of the coal supporting bottom plate to advance in place. In this case, it is easy to cause damage to the coal supporting bottom plate, coke side furnace door and furnace frame. At present, the overall smoke elimination effect of the furnace top smoke elimination truck and machine side smoke elimination system used in our factory is acceptable. But the maintenance of this system is no less than that of tamping machinery. The nozzles in the spray room of the stove top smoke elimination truck must be checked and replaced every week to ensure the atomization effect of the spray water. The bags of the machine side dust removal system require frequent backflushing and spraying to ensure that the color of the outdoor exhaust gas reaches the standard. In addition to the maintenance of the mechanical part, other problems include the deterioration of the smoke elimination effect and the hardening of the bag surface caused by changes in the moisture content of the coal. In terms of tamping operations, it should be noted that the last layer of floating coal must be manually compacted to reduce the smoke load on the furnace top smoke elimination truck. The top-loading coke oven was changed to a tamped coke oven. The obvious changes in the furnace body are the reduction of graphite on the furnace wall and obvious brick joints. Due to the phenomenon of coal collapse on the burner heads on both sides of the machine coke, local high temperatures on the furnace wall resulted in increased erosion and pitting on the wall surface. In response to this situation, thermal repair personnel should increase the frequency of inspection and maintenance of the furnace body. Wet gunning, troweling and semi-dry gunning require different maintenance methods for different parts and different degrees of damage. In order to realize the potential of the tamping process, the coking workshop needs to work hard to improve the operating rate of the equipment, standardize employee operations, ensure the solid density of the tamped coal cake, reduce smoke and dust, carefully maintain the coke oven body, and extend the life of the coke oven. 2.3 Production management of the chemical production workshop. The fineness of the blended coal required by the tamping and coking process is larger than that of the top loading process. This will easily cause a larger amount of dust in the gas, easily block the gas purification equipment, and increase the system resistance. Mainly manifested in the following aspects: The resistance of the primary cooler increases significantly faster than that of the top-loading process. The pipeline between the primary cooler and the fan is prone to accumulation of viscous matter. The liquid pipe under the primary cooler is easily blocked by accumulation. The slag discharge of the mechanized clarification tank obviously contains fine coal particles. The circulating washing oil of crude benzene can filter out the fine coal particles. In response to these situations, our unit has taken the following measures: Reduce the proportion of flotation washed coal, reasonably control the fineness and moisture of the blended coal, strictly require tamping operators to compact the coal cake floating coal, increase the circulating spray volume of the primary cooler, timely detect pipeline resistance and accumulation, and timely monitor the quality of the circulating washing oil. Practice has proven that taking the above measures can effectively ensure the safe and smooth operation of the gas purification system. 3. Conclusion The production management of tamping coking is based on the top loading process. Some process links have changed. We can only promote a virtuous cycle of coking production by increasing attention to key process links, exploring the rules of production management, mastering the rules and utilization rules. 3.1 Matching the lithofacies composition, fineness, and moisture of coal are the focus of the coal preparation workshop. 3.2 The operation rate of tamping machinery and equipment, the height and density of coal cakes, smoke and dust control in coke ovens, and the operation and maintenance of coke ovens are the focus of the coking workshop. 3.3 The chemical production workshop needs to focus on the normal operation of each gas purification equipment. Different furnace types have different aspect ratios and heating systems, and different types of tamping systems have different feeding methods and tamping modes. In this way, there will be differences in the control of each process link in coal preparation, coking and chemical production processes.