Is a wet air cooling + water cooling system commonly used for the tower top condenser in vapor separation units?
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Is a wet air cooling + water cooling system commonly used for the tower top condenser in vapor separation units? Can’t the wet air cooling system condense the oil and gas at the top of the tower separately?
In some cases, the condensation temperature is not high enough, and air cooling alone is not sufficient to achieve effective condensation; for example, during summer when temperatures are high while the temperature of the condensate water is relatively low, the heat absorption effect is better
There are generally three methods for the tower top condenser in gas separation units: 1. Direct water cooling with thermal bypass control, which is adopted by many plants； 2. Wet air cooling is used, along with bottleneck control; this is the approach adopted by Qingdao Refining and Chemical Industry ； 3. Dry air cooling + water cooling is adopted, with key points under strict control; Guangxi Petrochemical uses this approach ； Personally, I think there are advantages and disadvantages on both sides, mainly considering energy savings, water conservation, and habit control. Our relevant water-cooling operations.
Take a look at the design specifications: we use dry air cooling combined with water cooling, with a heat extraction ratio of 2:1. In summer, most of the fans for dry air cooling as well as those for water cooling need to be activated, and fine adjustments are made by controlling the amount of water used for cooling. Recently, we have installed variable frequency drives for the air cooling systems, which facilitates precise adjustments in both winter and summer
This situation is closely related to the region; in areas with water shortages, dry and wet air cooling is generally used, as it helps save energy and water. In terms of cooling efficiency, both methods should be able to achieve the desired results. As for the control method, it is also determined by the cooling method used.
Is dry air cooling effective in summer? The temperature at the top of the vapor compression unit is usually just over 40 degrees Celsius, while in southern regions the temperature can reach over 40 degrees Celsius during summer. Is air cooling then useful in such situations? When designing a system with both dry air cooling and water cooling, should water cooling be considered for full load conditions?