Enhancing Reliability and System Safety of Chiller Compressors in Radiological Plants: A Comprehensive Protection Approach

Chiller compressors are vital for maintaining optimal temperatures in radiological plants. Their intricate processes demand robust safety measures to ensure uninterrupted operation and mitigate potential risks. This study introduces a comprehensive protection approach designed to enhance the reliability and system safety of chiller compressors in radiological plants. Conducted at the Bhabha Atomic Research Centre (BARC), the research focused on chiller plants housing machines ranging from 300 ton of Refrigeration (TR) to 750TR. Despite standard protection features, occasional failures to trip under specific conditions triggered extensive investigations. The goal was to identify potential unsafe events and machinery damage within these systems. To enhance reliability and safety, a multifaceted protection system was developed. While the primary emphasis was on safeguarding chiller compressors, critical plant equipment was also included. This protection system employed a comprehensive array of hardware and software-based techniques to ensure uninterrupted chiller plant operation. The proposed approach involved modifications to protective circuits and the integration of redundant safety features. Specifically, closing and tripping coil circuits were reconfigured to respond promptly to deviations from specified process parameters. Additionally, an effective chiller water control system was implemented, optimizing resource utilization and providing an extra layer of safety. The reliability and safety of this approach were evaluated through implementation at PRAFPUL, BARC, a vital plant in the Department of Atomic Energy's nuclear program. The results demonstrated significantly improved reliability and system safety throughout the operational lifespan of the chiller plant. This study contributes to reliability engineering and system safety by presenting a comprehensive protection approach applicable to chiller compressors in various plants. It underscores the significance of robust safety measures in mitigating risks and ensuring uninterrupted operations. The proposed approach can serve as a benchmark for similar facilities, offering valuable insights for future research and practical implementation in chiller plant settings.