(81f) Quantitative Risk Assessment Comparison of Heater Burner System Designs

Maher, S. T., Risk Management Professionals
Hockett, K. D., Risk Management Professionals

The evolution of industrial heater burner system designs over the past three decades has involved increased application of redundancy, diversity, digital signal processing, and higher pedigree end-devices to improve heater safety. More recently features such as automatic double block and bleed systems have become part of many shutdown system designs. Some of the features installed are clear improvements to safety and reliability. However, while others provide clear safety improvements, they may compromise availability by increasing the potential for nuisance trips. Additionally, some features address one potential hazard but may increase the potential for another hazard. The primary purpose of this paper is to teach the reader how to effectively use Quantitative Risk Assessment (QRA) to solve challenging design problems. As a demonstration, QRA will be applied to the evolution of heater designs over the past thirty years to illustrate (and tabularly-compare) the safety improvements and availability tradeoffs for various designs. In addition, some of the more challenging heater burner system design-option decisions will be quantified and compared.