Gas Dehydration
AMR Process Inc designs, and fabricates gas dehydration process packages which include glycol dehydration, glycol regeneration units, and molecular sieve dehydration units. AMR Process glycol dehydration & glycol regeneration packages incorporate advanced engineering designs, high technology internals, and proven track records.
It is necessary to remove water from natural gas in order to prevent hydrate formation and to reduce corrosion. The formation of hydrates can be prevented by inhibiting hydrate formation in the free water phase or by gas dehydration to prevent a free water phase.
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Hydrate Inhibitors
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Gas Dehydration
Glycol Dehydration & Glycol Regeneration Units
 Glycol dehydration units or TEG dehydration units are the most economical type of natural gas dehydration where dew points depressions of 60° to 120°F are required. Triethylene glycol (TEG) is the most common type of glycol use for gas dehydration.
In the glycol dehydration process TEG is pumped to the top of a contactor tower where it is flow countercurrent with wet gas flowing up the tower, utilizing internal high efficiency structured packing for larger gas flows, or trays for smaller tower sizing, for efficient gas/liquid contacting. The TEG adsorbs water from the wet gas and is passed to the glycol regeneration unit where, very simply, adsorbed gases are flashed off and the water is removed from the reboiler by heating the wet glycol to around 400ºF at atmospheric conditions. The regenerated TEG is then pumped back to the contactor tower inlet.
Where high dew point depressions are required in the TEG dehydration process, high purity glycol regeneration is required. High purity glycols can be regenerated by utilizing stripping gas (dry natural gas) in the reboiler.
Molecular Sieve Dehydration
Molecular sieves will adsorb the highest amount of water, will produce the lowest water dew points and will also simultaneously sweeten and dry gas. Molecular sieve dehydration units are also much more expensive.
Molecular sieves are adsorbents made up of aluminosilicate crystalline polymers (zeolite), which remove polar components such as water, methanol, CO2 & H2S. They come in may forms including beads, granulars, extrudate & pellets. The molecular sieve, type, size, & shape selection is determined by the operation.
Typical performance of molecular sieve dehydration unit:
The process requires two or more adsorption towers, with one on-line removing water whilst the others are being regenerated. The adsorption tower is typically removing water for around eight to twelve hours. The bed is regenerated by heating the molecular sieve to around 450° to 500°F using a slip stream of dry process gas. The regeneration gas is returned to the process after it has been cooled and the free water removed.
AMR Process can offer the correct selection of hydrate inhibitor or gas dehydration equipment to meet client's requirements. AMR Process can supply glycol dehydration & glycol regeneration, and molecular sieve gas dehydration units and designs. AMR Process can supply process designs or supply the complete package, according to end user location, fabrication location, or client preferences.
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