Method for controlling abnormal furnace temperature of blast furnace according to temperature changes of cooling wall

Abstract

The invention relates to a method for controlling the abnormal furnace temperature of a blast furnace according to temperature changes of a cooling wall. According to the method, the fall-off positions and the fall-off amount of blast furnace slag crusts are timely identified through the data mining technology according to the temperature conditions of the cooling wall of the blase furnace, cooling water inlet-outlet water temperature change conditions and blast furnace heat load change conditions, then the measures that additional coke is added inside the blast furnace through a furnace top PLC system and the air temperature, the coal powder injection amount and the oxygen enrichment amount of an air blower on the lower portion of the blast furnace are adjusted are further taken to enable the furnace temperature to be controlled to be in a stable level, the stable and smooth operation of the blast furnace is ensured, and the blast furnace can run at the optimum interval. The control accuracy of the abnormal furnace temperature of the blast furnace is improved, and the service life of the blast furnace is prolonged.

Description

technical field [0001] The invention relates to the technical field of blast furnace abnormal temperature forecasting, in particular to a method for controlling the abnormal temperature of a blast furnace according to the temperature change of a cooling wall. technical background [0002] There are four systems for blast furnace operation, one of which is the thermal system. The thermal system refers to the system for maintaining the thermal state of the blast furnace. It is carried out around restoring a reasonable furnace temperature. Since the blast furnace is a high-temperature closed reactor involving complex physical and chemical changes, it is impossible to accurately grasp the temperature distribution in the furnace, and only a certain number of thermocouples can be used to indirectly and roughly reflect the temperature changes in the furnace. Generally, the blast furnace temperature is reflected by the temperature of slag and molten iron in the hearth. [0003] In...

AI Technical Summary

Problems solved by technology

The literature "Yasuo NIWA, Takashi SUMIGAMA, "Application of a Self-learning Function to an Expert System for Blast Furnace Heat Control", ISIJ International, Vol.30(1990), No.2, PP111~117" uses fuzzy control technology and Document "Chen Lingkun, "Application of Blast Furnace Smelting Expert System in Furnace Temperature Control", 2002, "2002 National Ironmaking Production Technology Conference and Ironmaking Annual Meeting Collection", P681~686", in which the method of using fuzzy control expert system Forecast the change of furnace temperature. This method uses parameters such as melting loss reaction carbon amount, heat index, heat load, feeding speed, air flow change and other parameters to predict the change of furnace temperature. The prediction accuracy is very high, and it can adapt to different furnace conditions. But this method can only predict the furnace temperature change in the next 2 hours or so. For 2000m 3 For the above-mentioned large-scale blast furnaces, once a serious abnormality occurs, even if the furnace temperature change can be predicted 2 hours in advance, the various measures taken within 2 hours are still difficult to play a role, and sometimes there will be accidents in the blast furnace. , will cause the hearth to work abnormally, and the slag-iron ditch will bond, which will cause a major hidden danger to normal production, and improper handling will lead to major accidents. 3 Taking the blast furnace as an example, there will always be more than 5 furnace cooling accidents in each blast furnace every year, which will cause hidden dangers to production

[0004] To sum up, since the fluctuation of furnace temperature is affected by many factors, any model involves the selection of variables, and it is difficult for a model to take all factors into consideration; and the same influencing factor is affected by different furnace conditions. It often has different contribution rates, which also objectively affects the prediction accuracy of the model.

When the furnace condition is abnormal, the furnace temperature prediction hit rate or forecast advance amount of the various furnace temperature prediction models that have been developed are not ideal

At present, the above methods cannot accurately and timely predict the defects affecting the thermal regime of the blast furnace

Caused inaccurate control of blast furnace abnormal furnace temperature