Washing tower
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Hello, everyone who is more experienced than me! I have simulated a gas purification process that includes a water scrubber tower. The main function of this tower is to use water containing NaOH to wash waste gas containing SO2 and phenol. The temperature of the waste gas is 90°, with a flow rate of 30,000 Nm3/h; the temperature of the water is 30°, and its flow rate is 56 m3/h. (The simulation files for versions 8.4 and 11.0 were uploaded separately.) The temperature of the gas at the outlet is 30°, and the temperature of the liquid at the outlet is 31°; these values differ somewhat from the actual process temperatures (where the gas temperature at the outlet reaches around 60° during actual operation). I tried to significantly reduce the water volume; I thought the temperature of the gas exiting would increase, but it only rose by one degree Celsius (31°). Dear seniors, please help me figure out what’s going on here – why is the temperature so strange? Thank you all!
In actual operation, the temperature of the gas exiting the tower reaches around 60°. When the water wash tower is in use, the structure of the tower also comes into play – whether its efficiency can match that of the simulations. Additionally, why does the software display two streams of water being fed in? Wouldn’t that result in twice as much water???:o
Structural issues may have an impact. The efficiency is as follows: since we know the actual packing height of the wash tower, we set this value directly during the design of the tower; the height of each tray is set to 1/6 of the packing height, resulting in a total of 6 theoretical trays. Our wash tower does indeed have two water inlets during spraying. So when conducting the simulation, I set up two water feeds; the amount of water used was appropriate, and the total volume of water from these two feeds was equal to the actual total feed volume. The problem now is that even when I significantly reduce the water volume, the exhaust temperature doesn’t increase noticeably; when the water volume is reduced to 1/10 of its original level, the exhaust temperature rises by only 1°, which seems to indicate a serious issue.
The feed gas contains no moisture, meaning its relative humidity is 0%. As a result, most of the heat is used for the evaporation of moisture, which causes the relative humidity of the outlet gas to reach 100%. Verify that the moisture content in the feed gas is indeed 0%
Thank you for the guidance from those who are more experienced! What the senior mentioned is indeed the key to the problem. After I changed the feeding conditions and increased the relative humidity of the incoming air, I observed a significant rise in temperature. This way, it corresponds pretty well to the actual situation! Thank you! Thank you! Thank you! {:2_36:} Learned something new again!