What is glycol dehydration process?
What is glycol dehydration process?
The dehydration process is simple—wet gas contacts dry glycol, and the glycol absorbs water from the gas. Wet gas enters the tower at the bottom. Schlumberger glycol dehydration processes remove water vapor from natural gas, which helps prevent hydrate formation and corrosion and maximizes pipeline efficiency.
Is ethylene glycol dehydrating agent?
Dehydrating Agents Low vaporization losses; Easy and economic to be separated and regenerated; Non-corrosive and non-toxic to the system. Glycols such as ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (T4EG) fall into this category.
Does ethylene glycol absorb water?
Water Absorption. Uninhibited ethylene glycol, like other glycols, is hygroscopic; it will absorb moisture from its environment. The amount of water absorbed from its environment is proportional to the percent relative humidity (figure 1).
How does TEG dehydration work?
For dehydration of natural gas by triethylene glycol (TEG) process to a lower water content/water dew point temperature a higher lean TEG concentration is required. Stripping gas lowers the water partial pressure causing more water to vaporize from TEG solution.
How do you dehydrate ethylene glycol?
Initially, the process used ethylene glycol as the absorbent but, with the advancement of the technology, glycol dehydration now involves the use of an aqueous solution of a glycol derivative in which the glycol is either diethylene glycol (DEG) or triethylene glycol (TEG) (Table 7.5), which is brought into contact …
Why glycol is used for dehydration?
Purpose. The purpose of a glycol dehydration unit is to remove water from natural gas and natural gas liquids. Glycol dehydration units depress the hydrate formation point of the gas through water removal.
Why is ethylene glycol soluble in water?
The hydrogen bonding in ethylene glycol. Thus, ethylene glycol and water molecules can form hydrogen bonds to each other, just as the individual molecules can, which means that they mix freely, in all proportions, as shown in the diagram below.
How does ethylene glycol affect water?
It lowers the freezing point of water (and raises the boiling point) and is also miscible with water in all proportions. And that is down to the properties of the molecule, particularly its ability to form hydrogen bonds.
Which glycol gives higher efficiency for dehydration of natural gas?
Tetraethylene glycol would have to be regenerated at higher temperatures than TEG to reach the required purity for application in a glycol dehydration unit. Thus, of the four glycols, TEG is the best suited for dehydration of natural gas.
Can you use ethylene glycol in a dehydrator?
Ethylene glycol (EG) is not used in a conventional glycol dehydrator, as described below. The main use of EG in the dehydration of natural gas is in depressing the hydrate temperature in refrigeration units.
What are the steps in the preparation of ethylene glycol?
An ethylene glycol stream comprises inorganic chloride contaminants and the process comprises steps of converting the inorganic chloride contaminants to 2-chloroethanol by reaction with ethylene oxide in one or more dehydration columns, and removing 2-chloroethanol in a waste water stream.
How is ethylene glycol used in the natural gas industry?
Ethylene glycol is used in the natural gas industry to remove water vapor from natural gas before further processing, in much the same manner as triethylene glycol (TEG). Because of its high boiling point and affinity for water, ethylene glycol is a useful desiccant.
Where does glycol go in the dehydration process?
The rich glycol then enters the glycol regenerator that contains the still column and reboiler, where the water is removed by distillation, and the glycol concentration is increased to meet the lean glycol requirement.
