Air-fin condenser

It is common for air to be the condenser coolant. Air-fin condensers comprise layers of finned tubes over which air is forced by fans. There are a number of ways in which air flow may be manipulated. As shown in Figure 12.35, the pitch of the fan blades or the fan speed can be adjusted. However there are usually a large number of fans in place. While it may not be necessary to install such mechanisms on all the fans, it does become costly and, like most... 

Air-fin condensers can be subject to rapid changes in ambient conditions. A sharp drop in temperamre or a rainstorm can cause the reflux to be subcooled. On entering the column the reflux is brought back to its bubble point by condensing some of the rising vapour. This condensed vapour provides additional reflux thus the internal reflux will be greater than the measured external flow. This then disturbs the product compositions. 

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