Calculation of water content in compressed air
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What is the saturated moisture content in compressed air at a certain temperature and pressure? How to calculate it? My previous idea was to use the saturated vapor pressure of water at a certain temperature as the partial pressure of water in the air. Divide this partial pressure by the total pressure to get the saturated vapor amount of water. Can it be calculated this way?
Your idea is okay, the water content calculated in this way is volume percentage.
hehe. The rough calculation is like this: Saturated vapor pressure/total pressure of water at a certain temperature * The amount of air is the saturated water content. This is the maximum moisture content. Then multiply by the relative humidity to get the true moisture content Ps/P * F * RH% The general unit of F for the moisture content of air is NM3/h. It can be converted to Kmol/h. 1Kmol=22.4Nm3/h. Get the number of moles of water and then convert it with the molecular weight to get how many tons of water you have. Try it yourself.
Thanks for the answer, but I still have questions. How do I find the relative humidity? Because the air is in the compressor aftercooler, its relative humidity cannot be measured. At a certain temperature and pressure, is the relative humidity of air a fixed value? The problem is actually that when air is compressed in three stages and heat is exchanged after each stage of compression, water will accumulate in the heat exchanger. Therefore, the heat exchanger is equipped with a drainage device. So how often should the water be drained?
The water content in the air is only related to the temperature and humidity of the air, and has nothing to do with the pressure of the gas. The water content of the gas in this case can be obtained by using a hygrometer and the ambient temperature.
There is a comparison table in the book Principles of Chemical Engineering, which shows the maximum moisture content of air (the saturated content in the air) relative to a certain pressure and temperature. Someone posted this in this forum. (empty reference)
There is no way to measure humidity now.
Your air compressor does not have a drain device? Common air compressors are available. Regularly drain heat exchanger water
The author can refer to this post http://bbs.hcbbs.com/viewthread.php?tid=235705&highlight=%BA%AC%CB%AE%C1%BF
If you have a drainage device, you just want to know how often you should drain it.