Glycol dehydration reboiler

Most glycol dehydration processes are continuous. That is, gas and glycol flow continuously through a vessel (the contactor" or absorber ) where they come in contact and the glycol absorbs the water. The glycol flows from the contactor to a reboiler (sometimes called "reconcentrator or regenerator where the water is removed or stripped from the glycol and is then pumped back to the contactor to complete the cycle. 

Pressures above atmospheric in the reboiler can significantly reduce lean glycol concentration and dehydration effieiency. The still column should be adequately vented and the packing replaced periodically to prevent excess back pressure on the reboiler. 

A typical triethylene glycol (TEG) dehydration unit is made up of two main components. The absorber, often known in the industry as the glycol "contactor" and the regenerator, is normally based on direct fired reboiling. The feed gas enters the bottom of the contactor and travels upward. The glycol enters the top of the tower and travels down. Thus dry gas leaves the top of the contactor and rich glycol (containing more water) leaves the bottom. 

Dehydration capacity vs. temperature (gas drying), 449-455 glycol circulation vs. tray capacity, 450-451 tray design, 451-452 reboiler temperature variable, 453 overheating glycol, 453—454... 

The glycol reboiler must have a sufficient heat-duty capacity to regenerate the glycol at a high enough temperature to adequately dehydrate the gas. 

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