Definition - What does Dehydration Units mean?
Dehydration units are assemblies of equipment that are useful in removing water vapors or moisture from natural gas. The units are the part of the upstream sector where the wet natural gas is treated for the removal of moisture content from it, thereby making it suitable for sale and meet the pipeline quality standards. This is done with the help of Triethylene Glycol (TEG).
Petropedia explains Dehydration Units
Dehydration units are important in natural gas processing facilities as they ensure that natural gas is dry and suitable for transport in the pipelines for sale. If wet natural gas is fed directly into the pipeline without treating it with Triethylene Glycol (TEG), the moisture content in the gas will corrode the inner part of the pipelines thereby damaging the integrity of the gas pipeline setup.
Water (moisture) absorption from natural gas with the help of TEG in the dehydration units is a very well-known and proven technology used by almost all the natural gas marketing organizations. It is the most common process used for gas dehydration. A lean TEG solution in a gas glycol contactor absorbs the water content from natural gas when the wet natural gas is passed from it. TEG solution that has absorbed water, known as Rich TEG is collected at the bottom of the contactor and is sent to the regeneration unit of the dehydration unit setup. In the regeneration unit, the water is vaporized in a re-boiler at low pressures and again left with lean TEG solution which is again pumped to the gas glycol contactor. The process is repeated again in the dehydration unit when the wet natural gas comes in contact with lean TEG.