Where can you filter glycol? Houghton Chemical. Filtration helps prolong the life of your inhibited glycol. We can filter your propylene glycol or ethylene glycol onsite or at one of our facilities. On site, we will load the inhibited glycol on the trailer and recharge the system while running the glycol through a filter. While you clean, flush, or repair your system, we can filter your glycol at one of our facilities. At any time, Houghton can also re-inhibit, adjust concentration, or add dye per your request. Website: www.houghton.com More Information: Houghton Chemical Specialized Glycol Services