2017 Spring Meeting and 13th Global Congress on Process Safety
(188d) Modeling Ethylene Plant Cracking Heater Burner Light-Off Safety Instrumented Functions
Author
By:
David Lewis
Functional Safety Engineer
NOVA Chemicals Corporation
Process Safety and Risk Services
P.O. Box 5006
Red Deer, AB, T4N 6A1
Email: David.K.Lewis@novachem.com
Abstract
Ethylene Plant Cracking Heaters require the design of Safety Instrumented Functions to help manage the risk of startup and operation of the Heater. Lighting off the burners on multiple burner Heaters can represent a high risk which may require a SIL 2 Safety Instrument Function (SIF) especially if the burners are manually lit by an operator. Designing and modeling this SIF can present challenges where multiple fuel isolation valves are required on multiple burner heaters and where there is limited opportunities to proof test the SIF.
This paper will discuss the challenges of designing and modeling the reliability of multiple burner Cracking Heater burner light-off SIFs and provide an example of how this can be accomplished.