Glycol as frost protection for water-lined cooling systems

Glycol is regularly used as frost protection for water-lined cooling systems. "Glycol is a chemical product based on petroleum and natural gas," knows Timon Bol of Conpro Condenser Protection. "A distinction is made here between two types - Mono Ethylene Glycol (MEG) and Mono Propylene Glycol (MPG) - which, like gasoline and diesel, for example, must not be mixed. Therefore, specific knowledge when refilling and replacing glycol systems is necessary."

Colloquially, MEG is the environmentally unfriendly glycol variant and MPG the environmentally friendly one, but both products should not be discharged into the environment. "Old glycols must be carefully disposed of and offered to an authorized processor," Bol said. "That's why we always provide a waste stream certificate 'spent coolants.'" Changing glycol types is not technically possible just like that, according to him, because the mixing ratios with water differ. "As a result, you run the risk of changing the viscosity (the thickness/ syrupiness) of the medium. If this is not provided for in the design - that is, if the engineering assumes a certain viscosity - then the application of a different medium can cause problems. For example, because pumps, piping and other fittings then no longer achieve the required design capacity."

Mix ratio repair

Glycols can age. "In this case, they do retain their frost-protective nature, but internal calcification and corrosion of the pipes is lurking due to acidification," Bol said. "In addition, the heat buffering capacity can decrease." Using a sample and in a laboratory, Conpro Condenser Protection can test the glycol mixture against the desired parameters to determine the quality of the medium. "This service is particularly economically attractive for large systems, because in many cases, with the addition of glycol or additives such as corrosion protectors, the mixture ratio can be brought back to the right level. Full flushing of the system, replacement of the glycol mixture and disposal of the old glycol content is not necessary in this case." In smaller systems, it is better to replace the glycol mixture immediately for cost efficiency reasons.

Complete service

"The bulk of water-lined refrigeration systems in our industry are MEG-based systems," Bol said. "These systems often have a ratio of 30% glycol to achieve the proper freeze protection of around -18°C. In this case, a glycol mixture 30/70 is called for." Conpro Condenser Protection supplies pure glycol and water/glycol mixtures from 25 liters to full tanker truck capacities. "In addition to supply, we also provide system cleaning and pumping in new glycol and water/glycol mixtures. Because in most cases a Plan of Action is expected quickly, expert knowledge is very important. Unfortunately, this is not (yet) a given. For example, we are currently restoring a system where a third party pumped the glycols on the wrong side (the inside). This caused the glycol to miss its function as a frost protector. This was repaired at a later stage, but the damage to the system had been done by then. It was up to us to repair this permanently."