The Assessment of Independent Layers of Protection in Gas Sweetening Towers of Two Gas Refineries
Irtiqa Imini Pishgiri Masdumiyat (Safety Promotion and Injury Prevention),
Vol. 2 No. 2 (2014),
20 December 2014
,
Page 103-112
https://doi.org/10.22037/meipm.v2i2.7037
Abstract
Backgrounds and objective:Process industries are required to provide and maintain the working places safe for their workers, neighbors and environment. Safety may be provided through inher-ent safety design, providing several safeguards including instrumentation, applying proper proce-dures and training. Layer of protection analysis (LOPA) is a semi-quantitative technique. This technique has been used to analyze the protecting layers independently. This study was carried out to assess the independent layers of protection analysis in controlling the likely risks in sweeten in gas units of two different gas purification plants.
Materials and Methods:In the risk assessment process, hazards were identified byHAZOP tech-nique at four nodes in each gas refinery and the incident scenarios were determined then. By using LOPA technique based on cause & effect, the level of risk for each scenario was determined con- sidering the protective layers. Finally, the collected data was analyzed using the LOPA standard method and PHA-Pro6 software.
Results:Despite the fact that the independent protection layers (IPLs) were different ineach re-finery sweetening towers, risk levels at different scenarios were similar.Thapplication of Inde-pendent protection layers may decrease the likelihood of scenarios. The safety integrity level of control equipment was SIL-4 but total probability of failure on demand (TPFD) was higher in second gas refinery.
Conclusion:The results suggested that safety integrity level (SIL) were the same in both gas re-finery sweetening towers while the protection layers were different. Results of research indicated that LOPA method can be used for controlling hazards based on layers of protection. Adding layers of protection to equipment are recommended to reduce the hazards to acceptable levels.
How to cite this article: Jafari, MJ, Askarian AR, Omidi L, Miri Lavasani MR,Taghavi L, Ashoori AR. The Assessment of Independent Layers of Protection in Gas Sweetening Towers of Two Gas Refineries. Irtiqa Imini Pishgiri Masdumiyat (Safety Promotion and Injury Prevention).2014;2(2):103-112.
- Risk Assessment, Integrity Level, Layer of Protection, HAZOP
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References
Arendt JS, Lorenzo DK. Evaluating process safety in the chemical industry: A user's guide to quantitative risk analysis. 1nd ed. New York: American Institute of Chemical Engi-neers; 2009.
Berg AR. Applicability of Layer of Protection Analysis to determine Safety Integrity Levels in the Process Industry [Dissertation]. Department of Production and Quality Engineer-ing:Norwegian University of Science and Technology; 2007.p.2.
Ouazraoui N, Nait-Said R, Bourareche M, Sellami I. Layers of protection analysis in the framework of possibility theory. Journal of hazardous materials. 2013;262:168-78.
Bridges W, Dowell III A, Gollin M, Greenfield W, Poulsen J, Turetzky W. Layer of Pro-tection Analysis: Simplified Process Risk Assessment Center for Chemical Process Safety. AIChE, New York, NY. 2001.
Summers AE. Introduction to layers of protection analysis. Journal of Hazardous Materi-als. 2003; 104(1):163-8.
Dowell III AM. Layer of protection analysis for determining safety integrity level. Isa Transactions. 1998;37(3):155-65.
Bell R. Introduction to IEC 61508. Proceedings of the 10th Australian workshop on Safe-ty critical systems and software - Volume 55; Sydney, Australia. 1151817: Australian Computer Society, Inc.; 2006. p. 3-12.
Lundteigen MA, Rausand M. Assessment of hardware safety integrity requirements. Reli-ability of Safety-Critical Systems: Proceedings of the 30th ESReDA Seminar; Trondheim, Norway: European Commission, Joint Research Centre; 2006. p. 185-98.
Jafari MJ, Lajevardi SS, Fam IM. Semi Quantitative Risk Assessment of a Hydrogen Pro-duction Unit. International Journal of Occupational Hygiene. 2013;5(3):101-8.
Habibi EA, Keshavarzi M, Yousefi HA, Hasanzadeh A. Outcome Analysis of Major Ac-cidents and Determining the Safety Integrity Level of Processes in Sour Water Stripping Unit of Gas Refinery Using LOPA Technique. health system research .2011;7(3):301-14. (Full Text in persian)
Lajevardi SS, Jafari MJ, MohammadFam I. Determining Safety Integrity Level on a Hy-drogen Production Unit with Application of the Layers of Protection Analysis Method. Journal of Safety Promotion and Injury Prevention 2014;2(1):23-30.
Mohammad Fam A. Safety Engineering. 3nd ed. Hamedan: Fanavaran; 2005. p.21-40. (Text in persian)
Zarei E, Jafari MJ, Badri N. Risk Assessment of Vapor Cloud Explosions in a Hydrogen Production Facility with Consequence Modeling. Journal of research in health sciences. 2013; 13(2):181-7.
Hairulanuar. Incident Classification and Reporting. In: HSE Management System, editor. June 2003.p. 17-30.
Beckman L. Determining the required safety integrity level for your process. ISA transac-tions. 1998; 37(2):105-11.
Tauffer T, editor. Making the Most of Alarms as a Layer of Protection. Safety Control Sys-tems Conference–IDC Technologies (May 2010).
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