Maintaining Thermal Fluid Systems

Many pharmaceutical manufacturers operate heat transfer fluid systems, but not all are aware of the benefits of preventative maintenance. Despite their pivotal role in production, the thermal fluid in a heat transfer system often goes unnoticed. Without correct maintenance, problems can occur within the system, causing expensive unplanned downtime, which impacts productivity.

Proactive maintenance

Proactive analysis and maintenance of heat transfer fluid is essential for pharmaceutical manufacturers. Fluids degrade over time, particularly at high temperatures, and this can lessen the efficiency of the system, reducing the heat-transfer properties. If fluid maintenance is conducted proactively, it is easy to restore the system to optimal condition. When testing and analysis show degradation, pharmaceutical manufacturers can perform maintenance activity such as dilution, filtration, or light-ends removal, before the system starts to perform inefficiently. Regular monitoring and maintenance activity can slow the degradation rate and prolong the life of the fluid.

If the system is left for a long period of time, thermal cracking and oxidation may occur. These processes form solid carbon which can build up and clog the pipes, decreasing system efficiency. There is a risk that solid carbon can be baked to the inside of the system if the problem is not corrected early enough. Carbon’s insulating properties can lead to the formation of hot spots, creating a further fire hazard. The consequences of blocked pipes and hot spots can be severe, including system breakdown, costly maintenance, and downtime. The operator must also consider the cost of flushing, oil disposal, and refilling the system.

Light ends

When a heat transfer fluid degrades, it can lead to the production of short-chained hydrocarbons, known as light ends. Light ends are a potential health and safety hazard because their lower boiling and ignition temperatures can reduce the overall flash point temperature of the fluid. This situation can be monitored by routinely testing the flash point.

Staying ahead

Plant managers should take steps to verify fluid condition to ensure it is safe and efficient. Regular, thorough testing and top-ups can be undertaken to establish the state of the fluid. A heat transfer system loses 5% of its volume per year, so all system operators should be aware that a top-up will be necessary, even if there are no leaks in the system.

Pharmaceutical manufacturers can detect problems and take preventative actions to minimize degradation and health and safety risks, keeping the system compliant and efficient. In a plant using a heat transfer fluid, the best option is to create a robust maintenance plan including site survey, training, thermal fluid top-up, and frequent fluid test and analysis.

About the author

Clive Jones is managing director of thermal fluid specialist Global Heat Transfer.