Compared to the relatively large volume of glycol applied as heat transfer liquid, only a few percent of this amount is returned for further processing each year in the European Union. Besides the fact these materials are normally contaminated with heavy metals after being used in cooling systems for years, they are hydrocarbon-based liquids producing additional GHG during incineration or disposal.

No glycol-specific methods can be found yet in the industry, but reverse osmosis and evaporation-based devices are the two most commonly mentioned in connection with filtering contaminated industrial liquids.