Intelligent graded furnace temperature control method for impulse nozzles

Abstract

The invention discloses an intelligent graded furnace temperature control method for impulse nozzles. When requirements of an oven of an impulse heating furnace are met, field manual ignition is conducted for part of impulse nozzles on the lower portion of a second heating section and on the lower portion of a soaking zone inside the heating furnace according to the curve of the oven; after ignition of ignition nozzles succeeds and ignition nozzles are burning stably, an ignition flame monitor detects the flame, and then a main nozzle ignition button is pressed down to conduct main nozzle ignition; after all main nozzles are ignited, whether the furnace temperature at that time exceeds 800 DEG C or not is determined according to the measured value of the furnace temperature of the impulse heating furnace; if the furnace temperature at that time exceeds 800 DEG C, the furnace temperature is controlled through impulse combustion; if the furnace temperature at that time does not exceed 800 DEG C, ignited impulse nozzles are interlocked at the lowest furnace temperature, so that the thermal load demand is locked at 100%, and impulse nozzles keep the normally-burning state in every calculating period, that is, impulse nozzles keep normal burning to meet the furnace temperature requirement. By the aid of the method, the furnace temperature volatility at the oven stage of the impulse heating furnace can be reduced, and the oven quality can be effectively improved.

Description

technical field [0001] The invention relates to a hot-rolled slab pulse heating furnace combustion technology, in particular to an intelligent graded furnace temperature control method for pulse burners. Background technique [0002] At present, many domestic steel mills are building or renovating pulse heating furnaces, transforming the original traditional combustion technology into pulse combustion technology. Pulse combustion is an effective energy-saving technology used in large slab heating furnaces in recent years. The so-called pulse combustion means that the furnace temperature is controlled by the time when the pulse burner is put into combustion. The combustion time has a certain period. To achieve the purpose of setting the furnace temperature, the burning time of the pulse burner is shown in Table 1. [0003] Table 1 Pulse burning time [0004] heat load demand Working hours (s) Remark 0≤Hd≤10% Pulse burner not working, always off ...

AI Technical Summary

Problems solved by technology

However, in the existing pulse burner combustion control flow chart, whether the main burner "ignites successfully" or not is manually confirmed, and the gas valve is continuously "on" and "off" according to the heat load demand, so when the pulse burner When pulse combustion is performed at low temperature (especially when it is lower than the ignition point of gas), if the ignition burner goes out and the flame monitor of the ignition burner detects an error or fails, the main burner does not ignite due to pulse combustion. The furnace temperature keeps dropping, and according to the interlocking conditions of the pulse burner input heat load demand, the gas valve will remain open for a long time to ensure the temperature rise, which will eventually lead to a large amount of gas accumulation in the furnace, resulting in the risk of detonation

[0014] At the same time, the low-temperature stage of the furnace requires the furnace temperature to be stable. Such frequent "on" and "off" will not only cause the refractories in the furnace to be washed intermittently by the high-temperature flame during the furnace start-up stage, thus affecting its life.

Moreover, due to safety requirements, operators need to go to the site regularly to track and confirm the pulse combustion situation. If the ignition burner goes out, they need to re-ignite, which greatly changes the operating habits of operators and increases their labor intensity.

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