Raining Flue Gas: How to Avoid Problems with Water Dripping Down

[peet_dk]

Hello

I have some flue gas coming from a smokestack into the air. The flue gas contains a lot of water, and when it goes into the sky on a cold winter morning, the relative humidity will rise to 100%, and then there will be a problem with water dripping down.

But… When the dripping water is not at problem, if the wind speed is high enough, because the water then will be scattered out.

By using the Mollier h-x diagram I know the kg. water per hour that will drip down.

But does anyone know a “rule of thumb” or something like that, to get a picture of when it will be a problem, and when area that the water will dripping down at will be large enough, so it isn’t a problem.

 

[AndyW]

Hello,

Thank you for bringing up this interesting question. I can provide some insights on this topic. First of all, the amount of water dripping down from the flue gas will depend on several factors such as the temperature and humidity of the surrounding air, wind speed, and the chemical composition of the flue gas itself.

To determine when it will be a problem, you can use the Mollier h-x diagram to calculate the amount of water that will drip down at different temperatures and humidity levels. However, as you mentioned, a "rule of thumb" can also be helpful in getting a general idea. In this case, I suggest considering the dew point temperature as a reference. The dew point temperature is the temperature at which the air is saturated with water vapor, and any further decrease in temperature will result in condensation. If the temperature of the surrounding air is close to or below the dew point temperature, it is more likely that water will drip down from the flue gas.

In terms of wind speed, you are correct that it can help scatter the water droplets and prevent them from dripping down. However, it is important to note that the wind speed should be strong enough to break up the water droplets, but not too strong that it blows the droplets onto nearby surfaces.

I hope this information helps in understanding when the dripping water will be a problem and when it will not. It is always best to consult a professional for a more accurate assessment, as the specific conditions of the smokestack and surrounding environment can also play a role. Thank you for your question and happy researching!