Cost Effective Alternatives to Changing Thermal System Fluid
By Michael R. Damiani, Radco Industries Inc. During normal operation, heat transfer fluids can degrade due to thermal stress or oxidation. Fluids can also become contaminated through heat exchanger leaks. Often, degradation and contamination lead to a significant decrease in heat transfer fluid efficiency, increasing production time and costs. In many cases a full fluid change-out may be required to restore system performance, but many times these other cost-effective alternatives listed below can extend fluid life and maximize system performance: Fluid Reprocessing. Degraded or contaminated fluid is removed from the system and sent to the fluid manufacturer for reprocessing. Low boilers and high boilers are separated by distillation and the recovered heat transfer fluid is sent back to the original user. Reprocessed fluid will usually meet new fluid specifications. Partial fluid volumes can be drained from the system and sent in for reprocessing, allowing continuous operation and eliminating a system shut-down. Reprocessing costs are based on the total quantity shipped and offer significant savings over the purchase of a new charge. Fluid Filtration. The formation of hard carbon or coke particles can lead to the fouling of heat transfer surfaces. By using portable filtration units brought on site, a service team from a fluid manufacturer can remove these particles either while the system is in operation or during a shut-down. On-site filtration saves transportation costs and fluid drainage time and expense. Partial Fluid Change-Out. Replacement of a percentage of the initial fluid charge with new fluid can improve performance by diluting degradation by-products and/or contaminates to within acceptable limits. Often the off-spec fluid that was removed from the system can be returned to the fluid manufacturer for credit, or can be reprocessed, returned, and kept on-site for future make-up requirements. These options can save system downtime and reduce overall heat transfer fluid costs, while maximizing system performance.