Safety Integrity Level (SIL) Study for Dolphin Energy’s Onshore Plant

Safety Integrity Level (SIL) for Dolphin Energy's Onshore Plant

Overview of SIL Study for Dolphin Energy

iFluids Engineering and Consultancy WLL was entrusted to perform a Safety Integrity Level (SIL) Study for Dolphin Energy’s Onshore Plant. This study plays a critical role in assessing the integrity of safety systems to ensure operational reliability and mitigate hazardous events effectively.

What is a SIL Study?

A Safety Integrity Level (SIL) Study evaluates the integrity requirements of Safety Instrumented Functions (SIF) assigned to Safety Instrumented Systems (SIS). The study leverages the Layer of Protection Analysis (LOPA) methodology to identify protective layers that prevent or mitigate the effects of hazardous events. By integrating inherently safe design concepts, the SIL study ensures compliance with international safety standards and minimizes risks effectively.

Key Aspects of a SIL Study:

A Image titled "Key Aspects of a SIL Study" with four hexagon-shaped numbered points. The points include: 01 - LOPA Methodology, 02 - Independent Protection Layers (IPLs), 03 - Risk Tolerance Criteria, and 04 - SIF Loop Integrity. Each point is displayed in a red hexagon with white text, connected to corresponding labels in arrow-shaped boxes.
Key Aspects of a SIL Study: LOPA, IPLs, Risk Criteria, SIF Integrity.
  • LOPA Methodology: Simplified, semi-quantitative risk assessment methodology.
  • Independent Protection Layers (IPLs): Analyze the likelihood of failure of protective systems.
  • Risk Tolerance Criteria: Compare mitigated scenario frequencies against company-defined criteria.
  • SIF Loop Integrity: Assign appropriate SIL levels based on risk analysis.

About Dolphin Energy

Dolphin Energy Limited plays a vital role in natural gas production and supply from Qatar’s North Field. The extracted gas is transported via subsea pipelines to the Onshore Gas Treatment Plant (OGTP) in Ras Laffan Industrial City (RLIC), where it undergoes treatment before delivery to the United Arab Emirates (UAE).

Objective of the SIL Study

The primary objective of the SIL Study is to:

  1. Identify and evaluate safety instrumented systems (SIS) required to prevent or mitigate hazardous events.
  2. Utilize inherently safe design concepts to enhance operational safety.
  3. Determine appropriate SIL levels for safety functions to ensure compliance with IEC Standards.

Specific Goals:

  • Mitigate risks associated with identified hazards.
  • Ensure proper classification and assignment of SIL levels to SIFs.
  • Optimize safeguards for maximum safety and reliability.

Methodology and Findings

Methodology:

The SIL study adopts the LOPA methodology to:

  • Identify initiating causes and evaluate their frequencies.
  • Assess IPL effectiveness in mitigating risks.
  • Assign appropriate SIL levels based on risk tolerance.

Observations:

  • HAZOP Recommendations: Incorporated into SIL assignments to enhance safety measures.
  • Fire and Gas Detection: Identified as a critical IPL but limited to SIL 1 due to technological and environmental limitations.
  • Detector Placement: Recommends a separate study to assess the adequacy and positioning of fire and gas detection devices.

Key Notes:

  • SIF loops were evaluated with and without HAZOP recommendations.
  • Improper detector placement or adverse environmental conditions can impede hazard detection, requiring further optimization.

Compliance and Standards

The SIL study strictly adheres to IEC Standards for:

  • SIF Integrity Levels: Ensure adequate safeguards for specific hazards.
  • Systematic Risk Reduction: Address risks effectively through robust safety instrumented functions.

Conclusion

The SIL Study for Dolphin Energy’s Onshore Plant provides a comprehensive assessment of safety requirements. By leveraging LOPA methodology, the study ensures that the safety systems meet international standards, thereby safeguarding operations and reducing potential risks.