基于流程仿真的炼钢-连铸区段运行效率分析

Analysis on operational efficiency of steelmaking-continuous casting section based on process simulation

炼钢-连铸区段是钢铁制造流程的核心区段,其运行效率对于流程整体运行的高效-稳定、协同-连续具有重要影响。如何进一步提升炼钢-连铸区段的运行效率,是“碳达峰”“碳中和”背景下钢铁行业面临的重要课题之一。以国内某转炉炼钢厂为研究对象,基于实际生产数据的解析,采用Python工具构建炼钢-连铸区段运行仿真模型,并以钢包周转周期、在线周转钢包数量、出钢至开浇时间、周转过程总等待时间、最大完工时间作为评价指标,系统研究排程规则等生产因素对炼钢-连铸区段运行效率的影响。此外,基于低碳、低成本生产的迫切要求,初步探究转炉高废钢比冶炼和夜间LF精炼类钢种集中生产2类模式下炼钢-连铸区段的运行效率。研究结果表明,所研究生产因素对炼钢-连铸区段运行效率影响程度的排序为排程规则>工序作业周期匹配性>工序作业周期波动。相比于炉机一一对应和设备作业均衡排程规则,所研究炼钢厂目前采用的设备最早可用排程规则更适用于复杂生产工况,在此基础上,通过缩小精炼周期波动范围可进一步提高炼钢-连铸区段运行效率。所研究炼钢厂“1座转炉高废钢比冶炼+2座转炉常规冶炼”的模式具有可行性,对于超低碳钢,高废钢比炉次的比例控制在15%为宜,同时,为保证运行效率,需满足前后工序生产节奏的匹配。夜间LF精炼类钢种集中生产模式能否有效实施的关键在于连浇炉数的控制,其中,典型低碳钢、包晶钢的合理连浇炉数范围分别为8~12炉和6~9炉。提出的流程仿真方法也可用于炼铁、轧钢等区段运行效率的研究,具有较高的普适性。

The operational efficiency of steelmaking-continuous casting section(SCCS)has a significant impact on the efficiency-stability and collaboration-continuity of steel manufacturing process,since it is a key section.How to further improve the operational efficiency of SCCS is an important issue for the steel industry in the context of"carbon peaking","carbon neutrality".A domestic BOF-based steelmaking plant as the research object was taken,and Python tool was used to construct a model for simulating the operation of SCCS in terms of the analysis of actual production data.The effects of scheduling rules and other factors on the operational efficiency of SCCS are systematically studied using the simulation model,and the evaluation of results are carried out by using indicators of the turnover time of ladles,the turnover number of ladles,the time from tapping to casting,the total waiting time for turnover process and makespan.In addition,the operational efficiency of SCCS under modes of the high scrap-ratio BOF smelting and the centralized production of LF-based steel at night are preliminary studied,based on the urgent requirement of low-carbon and low-cost production.The results indicate the order of factors influencing the operational efficiency of SCCS is scheduling rules>the matching of processing time>the fluctuation of processing time.The current scheduling rule based on the earliest available equipment adopted by the studied steelmaking plant is more effective than those based on one-furnace to one-caster and the balanced equipment operation rate.By using the scheduling rule based on the shortest transfering time,the operational efficiency of SCCS can be further improved by narrowing the fluctuation range of refining time.The mode of"one BOF used for high scrap-ratio smelting+two BOFs used for normal smelting"is feasible for the studied steelmaking plant.It is advisable to control the heat ratio of high-scrap ratio to 15%for ultra low carbon steel,and to ensure operational efficiency,it is necessary to match the processing times of different processes.The availability of the centralized production mode of LF-based steel is influenced by continuous casting heats significantly.For the studied steelmaking plant,it is suggested to control the heat number for continuous casting to 8-12 and 6-9 respectively for typical low carbon and peritectic steels.The process simulation method proposed shows a high universality and can be used to study the operational efficiency of ironmaking and rolling sections as well.