As a CPI Fluid Engineering brand, Paratherm is a respected heat transfer fluid (HTF) range. High-performance thermal oils, they are specially formulated to provide precise temperature control in heat transfer systems with a closed loop design.
They offer a multitude of benefits that include low viscosity, excellent oxidation resistance, outstanding thermal stability, and an impressively wide operating range that extends from -88 °C up to 357 °C. Product options like Paratherm HE and Paratherm NF see use in a variety of different industries ranging from food and beverage manufacturing to chemical processing.
While under normal operating conditions these stable lubricants can outlast many mineral and synthetic alternatives from rival brands, their active service life can be extended even further. This lets companies enjoy a higher return on investment (ROI) each time they purchase a supply of Paratherm HTF. Here, we look at some of the most popular strategies to prolong the life span of these cutting-edge thermal fluids.
Implement nitrogen blanketing
In heat transfer systems, oxidation causes sludge formation, acid buildup and gelling in thermal fluids. It is widely accepted as the arch-nemesis of lubricants and causes them to degrade at a rapid rate relieving them of their coveted characteristics. A much-favoured method of eliminating potential contact with oxygen is to fit a nitrogen blanket on the system’s expansion tank. This effective layer of inert gas not only prevents oxidation but also eradicates moisture contamination extending fluid life. It also reduces risks of fire hazards.
Annual fluid analysis
Heat transfer fluids require testing every 12 months at minimum. This can identify signs of thermal degradation, changes in viscosity, moisture or solids-based contamination, oxidation and high acidity levels. It’s understood that more frequent analysis (bi-annual or quarterly) is required for systems with higher usage. This diagnostic process allows for targeted maintenance instead of premature and costly fluid replacement, and helps achieve optimal fluid performance while reducing sludge buildup.
Maintain correct flow rates
System operators should ensure sufficient thermal fluid flow. This prevents fluid film temperatures from exceeding a Paratherm HTF’s maximum limit and avoids unwanted consequences like heater coking and thermal cracking, a form of thermal degradation where hydrocarbon molecules break down.
Use side-stream filtration
To lengthen the life span of Paratherm thermal fluids, users can also implement side-stream filtration. This approach ensures that particles and contaminants suspended in fluids are continuously removed, not only promoting a fluid’s expected service life, but also boosting the health and longevity of the heat transfer system. Employing high-temperature filtration that has a rating of 50 microns (or even finer) is a considered a critical strategy to extract particulate matter in thermal oils.
Manage system temperatures
Paratherm HTFs include manufacture recommendations for film temperatures. System users should not exceed the maximum temperatures advised and should check that the system heater is correctly designed to cope with the heat load. Ignoring guidelines can result in thermal degradation that shortens the service life of fluids.
Performing proactive maintenance
In terms of system care, preventative maintenance can also promote thermal fluid longevity. Heat transfer systems that are kept clean and free of contaminants ensure thermal oils stay in optimal condition. Oxidation issues that degrade oils can also be avoided by identifying leaks early and ensuring pumps are operating properly so the system doesn’t ingest air.
Dilution of contaminated thermal fluids
Over time, even advanced thermal fluids like Paratherm deteriorate during service. Contaminants that build up inside heat transfer systems reduce how efficiently fluids transfer heat. When fluids are only slightly degraded, they can sometimes be rejuvenated by adding fresh fluid. This dilution process can help extend the life of thermal oils. However, it is not a fix for circumstances when an HTF has degraded completely.
Proper storage
How heat transfer fluid is stored can also have a critical impact on its service life. Drums of Paratherm HTF should always be stored indoors under climate-controlled conditions in sealed containers to keep them protected against moisture, contamination and oxidation. The best practice is to store fluids off the ground using racking to avoid dust contamination and to only open containers when ready to use.
Following the advice above, system operators can extend fluid life span and get the maximum use of a supply of Paratherm HTF.
