The significance of the α value in tempering processes
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The significance of the α value in tempering work: When gas burns in the vertical flame channel, appropriate air must be supplied. If the amount of air is insufficient, combustion is incomplete, and the heat released by the burning gas cannot be fully utilized; as a result, the gas is wasted or the temperature in the vertical flue decreases. In particular, after the gas that has not burned completely passes through the regenerator chamber, it will ignite when it comes into contact with air leaking in, causing the regenerator chamber to reach high temperatures, which is very dangerous ； If the amount of air is too large, the combustion flame becomes short, which is not conducive to uniform heating from above and also reduces the temperature in the vertical flue. Therefore, regularly measuring the α value is very useful for providing timely guidance in tempering work.
The theoretical value of a is 1.15~1.25, but it seems not very suitable in actual production. Dear sea friends, could you analyze whether there is an appropriate range for this value in actual production?
In our plant, the value is actually maintained at 1.25–1.30 when using blast furnace gas, and at 1.30–1.35 when using coke oven gas. This post was last edited by 26722672 on 2009-2-21 23:51]
The a value should be analyzed simultaneously with the exhaust gas composition, in order to ensure complete combustion of the gas while also avoiding excess air that would lead to heat waste.
At our plant, the oxygen content at the exhaust gas outlet is between 1.35 and 1.45, while it ranges from 7 to 9%. At the viewing ports, the oxygen content is between 1.15 and 1.25. The type of furnace is JN60
For the JN60 furnaces I’ve worked with, which are heated using blast furnace gas, the analysis results for the exhaust gases from the small flues or branch flues are usually around 1.4. Although this value is much higher than the theoretical value, and it would be desirable to reduce it, it seems there are no effective ways to do so. I haven’t worked with furnaces heated solely by coke oven gas, so I’m not very familiar with that situation.
The a value is theoretically important, but it is not applicable in actual production. I believe this is due to the significant influence of the instruments and reagents used, as well as operational factors; as a result, the value obtained is not very accurate or varies considerably, and it cannot serve as a reference for actual production.
It’s 1 here. 25～1,35
This depends on whether it is compacted coke or top-loaded coke; the control values are different.