Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
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A Study on the Improvement of Reliability of Safety Instrumented Function of Hydrodesulfurization Reactor Heater

수소화 탈황 반응기 히터의 안전계장기능 신뢰도 향상에 관한 연구

  • Kwak, Heung Sik (Dept. of Safety Engineering, Graduate School of Industry, Seoul National University of Science and Technology) ;
  • Park, Dal Jae (Dept. of Safety Engineering, Seoul National University of Science and Technology)
  • 곽흥식 (서울과학기술대학교 산업대학원 안전공학과) ;
  • 박달재 (서울과학기술대학교 안전공학과)
  • Received : 2017.05.08
  • Accepted : 2017.08.14
  • Published : 2017.08.31
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Abstract

International standards such as IEC-61508 and IEC-61511 require Safety Integrity Levels (SILs) for Safety Instrumented Functions (SIFs) in process industries. SIL verification is one of the methods for process safety description. Results of the SIL verification in some cases indicated that several Safety Instrumented Functions (SIFs) do not satisfy the required SIL. This results in some problems in terms of cost and risks to the industries. This study has been performed to improve the reliability of a safety instrumented function (SIF) installed in hydrodesulfurization reactor heater using Partial Stroke Testing (PST). Emergency shutdown system was chosen as an SIF in this study. SIL verification has been performed for cases chosen through the layer of protection analysis method. The probability of failure on demands (PFDs) for SIFs in fault tree analysis was $4.82{\times}10^{-3}$. As a result, the SIFs were unsuitable for the needed RRF, although they were capable of satisfying their target SIL 2. So, different PST intervals from 1 to 4 years were applied to the SIFs. It was found that the PFD of SIFs was $2.13{\times}10^{-3}$ and the RRF was 469 at the PST interval of one year, and this satisfies the RRF requirements in this case. It was also found that shorter interval of PST caused higher reliability of the SIF.

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References

  1. K. H. Kook, "A Study on Present Status and Prevention Measures of Safety-related Accidents in Chemical Plants", Master Thesis, Chongnam National University, pp. 45-48, 1999.
  2. International Electrotechnical Commission, "Functional Safety of Electrical/Electronic/Programmable Electronic Safety-Related System", IEC 61508, 1998.
  3. International Electrotechnical Commission, "Functional Safety - Safety Instrumented System for the process Industry sector", IEC 61511, 2003.
  4. J. H. Kim, "A study on safety Enhancement of Chemical Plants using SIL(Safety Intergrity Level)Method", Master Thesis, Kwangwoon University, Seoul, 2010.
  5. I. J. Lee, "Safety Enhancement of LPG Terminal by SIL Method", Master Thesis, Seoul National University of Science and Technology, 2015.
  6. T. Thepmanee and P. Khamkoon, "SIL Assessment and Implementation Case Study: A Safety Instrumented Function for Overpressure Protection in a Two-Phase Gas-Liquid Separator", ICIC Express Lletters, Part B, Applications: an international journal of research and surveys, Vol. 5, No. 1, pp. 45-50, 2014.
  7. P. Baybutt, "Using Risk Tolerance Criteria to Determine Safety Integrity Levels for Safety Instrumented Functions", Journal of Loss Prevention in the Process Industries, Vol. 25, No. 6, pp. 1000-1009, 2012. https://doi.org/10.1016/j.jlp.2012.05.016
  8. E. Colin, "Safety Integrity Verification of Legacy Systems", Measurement and Control, Vol. 42, No. 6, pp. 185-189, 2009. https://doi.org/10.1177/002029400904200605
  9. C. A. Lassen, "Layer of Protection Analysis (LOPA) for Determination of Safety Integrity Level (SIL)", Master Thesis, Norwegian University of Science and Technology, Norway, pp. 6-17, 2008.
  10. A. E. Summers, "Introduction to Layer of Protection Analysis", Journal of Hazardous Materials, Vol. 104, pp. 163-168, 2003. https://doi.org/10.1016/S0304-3894(03)00242-5
  11. E. M. Marszal and E. W. Scharpf, "Safety Integrity Level Selection: Systematic Methods Including Layer of Protection Analysis", International Society of Automation, pp. 181-182, 2002.
  12. A. Summers and B. Zachary, "Partial-stroke testing of safety block valves", Control Engineering, Vol. 47, No. 12, pp. 87-89, 2000.
  13. M. A. Lundteigen and M. Rausand, "The Effect of Partial Stroke Testing on the Reliability of Safety Valves", The European Safety and Reliability Conference, Stavanger, Norway, June 25 - 27, pp. 1-15, 2007.
  14. Y. H. Lee, "Understanding the Partial Stroke Test", Instrumentation technology, pp. 133-137, 2011.
  15. Korea Occupational Safety and Health Agency, "A Manual of Review Technique for Petrochemical Process - NCC Process part", pp. 79-81, 2007.
  16. H. Stein and P. Hokstad, "Reliability Data for Safety Instrumented Systems : PDS Data Handbook", Trondheim, SINTEF Industrial Management, Norway, p. 64, 2004.
  17. OREDA, "OREDA : Offshore Reliability Data Handbook (4th ed.)", SINTEF Industrial Management, Det Norske Veritas, Norway, p. 173, 2002.