Membrane Based Triethylene Glycol Separation and Recovery from ...

2.1.2 Uses of TEG (Triethylene glycol)
The main uses for triethylene glycol are based upon its hygroscopic quality. TEG used as
a dehydrating agent for natural gas pipelines where it removes the water from the gas
before being condensed and reused in the system. Moreover, TEG also has a
dehumidifying agent in air-conditioning units. TEGs used to make chemical intermediates
such as plasticizers and polyester resins. In addition, TEG is used in many products
including automotive antifreeze, brake fluids and industrial solvents (Leth and Gregersen,
2005), and TEG is also used as a solvent in many applications, including as a selective
solvent for aromatics, and a solvent in textile dyeing. Triethylene glycol also has mild
disinfectant qualities and, when volatized, is used as an air disinfectant for virus and
bacteria control.
Manufacture of
Ester
Derivatives, 12
Miscellaneous,
19
Solvent, 11
Figure 2.2 Major uses of TEG (Alberta Environment, 2012)
However, the usage of TEG as adsorbent in gas dehydration may affect human, animal and
contaminate in the environment. TEG may transport into soil, release into the river, and
accumulate in sediment at the bottom of the river by rapid run off during the rainy season
and finally affect aquatic and human health.
2.1.3 Distribution in environment
No information was found that would indicate DEG (diethylene glycol), TEG, or TREG
(tetraethylene glycol) occur naturally in the environment. Accordingly, their distribution in
the environment is expected to be strongly biased towards facilities where these
compounds are produced or used. The number of facilities where the Glycols are used is
significant. In the U.S., national surveys of occupational hazards were carried out in 1974
and 1983. The 1983 survey indicated that the number of facilities where these glycols was
used and the number of employees exposed to each was:
5
Vinyl
Pkasticizer, 13
Natural Gas
Dehydration,
45