Flue gas cooling issue
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I have a question for those who are familiar with this process: when flue gas needs to be cooled from 240°C to 150°C by injecting a small amount of cooling water at 25°C, does it vaporize immediately? For flue gas at 240°C and a flow rate of 30,000 cubic meters per hour, which cooling method is the best? Is it water-cooled?
If possible, install a economizer: lol
The owner doesn’t have such an idea. My task is to ensure that the exhaust gases meet the required standards; I need to reduce the temperature to 150°C. All I need to do is lower the temperature. Is it necessary to use a cooling tower? I’m not sure whether spraying water into the flue will cause the vapor to evaporate immediately.
With a flow rate of 30,000 standard cubic feet, it’s a bit difficult to reduce the temperature from 240°C to 150°C; one could try designing multi-layer circular or dendritic distribution tubes for spraying water.
Thank you, big boss. I’ll first calculate how much heat is released when the temperature drops, to figure out what needs to be done. If water is used for spraying, I need to determine how much water is required. I think if I spray less, it must have vaporized.
By accurately calculating the heat required from water, it is possible to determine how much water is needed. There should be no problem. Incomplete vaporization is not a problem; an appropriate margin can be considered for the water spray volume, and a drain valve can be installed at the lower point to remove the condensed water.
Air cooling is sufficient; using water would result in high water consumption. Moreover, the spraying causes moisture in the flue gas, which makes subsequent treatment difficult.
It is recommended that customers install an air preheater or economizer, as it is simple, environmentally friendly, and energy-saving
I agree with what was said above: adding a heat exchanger to preheat the air or heat the water is energy-efficient, environmentally friendly, and doesn’t result in any waste.
We can help you build a heat pipe air preheater; the preheated air is then fed into the furnace for combustion, thereby improving efficiency