钢铁企业能耗瓶颈诊断数学模型及应用

Mathematical model for diagnosis of energy consumption bottlenecks in steel plants and its application

针对钢铁厂物质流和能量流对能耗同时产生影响的问题,建立了能耗瓶颈诊断模型.模型分别用钢比系数和工序能耗衡量物质流和能量流,其功能是将吨钢综合能耗的变化分解为钢比系数的变化和工序能耗的变化,从而将两种因素的影响相分离,寻找能耗瓶颈.模型分析通过三步进行,分别针对总流程、区域和工序,形成了系统的分析体系.同时,提出了贡献指数的概念,以定量地描述各个因素对吨钢综合能耗的影响大小.利用该模型对某钢厂2001年和2007年的能耗指标进行实例分析,找出了相应的能耗瓶颈为炼铁区域和轧钢区域钢比系数的增加与炼钢区域工序能耗的上升,并提出了增加热送热装比、降低加热炉燃料消耗等节能对策.

In order to solve the problem that material flows and energy flows both have influences on energy consumption in steel plants,a diagnosis model of energy consumption bottlenecks was established.The model uses steel ratio and process energy consumption to measure the material flows and energy flows,respectively.The function of the model is to decompose the change in energy consumption per ton steel into the changes in steel ratio and process energy consumption,so that the two factors effects can be separated, and thus the energy consumption bottlenecks can be found. The model analysis was done through three steps, correspondingly aiming at the main-process stream, the district and the process. Meanwhile, a new concept of contribution index was defined, which can indicate the effects of every factor on the energy consumption per ton steel. The model was applied to analyze the energy consumption indexes of a typical iron and steel enterprise in China using the data of energy consumption in 2001 and 2007, and the energy consumption bottlenecks in the steelmaking process were analyzed. The result shows that the restraining factors of energy consumption are the steel ratio of iron making district and steel rolling district and the process energy consumption of steel making district. At last, energy-saving measures, such as increasing the ratio of hot load and hot transportation and cutting down the fuel consumption of heating furnaces, were proposed.