Fire survivability analysis and blowdown system design

A PSE Oil & Gas seminar

This seminar describes how to apply an analytical methodology to assess vessel survivability under fire attack, and so inform blowdown system design. Updated industry standards, including the 6th edition of API 521, now recognise the need to consider vessel stress during blowdown and, critically, that guidance issued prior to 2014 may not be an appropriate basis for vessel survivability. The session explains why vessels are at risk when exposed to fire, the potential for loss of containment and the possible escalation to a major hazard.

The seminar explains the basis and importance of the new guidance as well as an analytical methodology for blowdown system design. The impact on process design is evaluated through a series of relevant project case studies in offshore platforms and gas processing facilities. These case studies demonstrate how a fully integrated dynamic model optimizing transient blowdown loads with available flare capacity improves accuracy, reduces uncertainty, and provides solutions to complex situations where application of Passive Fire Protection is not practical or flare capacity is limiting.

Typical seminar agenda

The precise timing and content will vary with each seminar. The registration forms will include a downloadable agenda specific to each seminar, as well as venue and travel information.

8:30 Registration, refreshments
9:00 Session 1 – Fire analysis and overpressure protection requirements

  • Basis for provision of pressure relief devices and depressuring systems
  • Pool and jet fires
  • API 521 6th edition requirements for depressuring
  • PSE Oil & Gas and gFLARE
9:30 Session 2 – Guidelines and workflows

  • Guidelines for API 521 empirical and analytical methods
  • The analytical method for fire analysis
    • Vessel wall temperature
    • Stress calculations and rupture prediction
    • Validation: BAM fire test and analysis
  • Fire analysis workflows: flare limitations, rupture
    • Aims and key considerations RO sizing, flare limits, rupture, Passive Fire Protection
    • Conventional workflows, tools and limitations
    • Handling of uncertainty
11:00 Refreshment break
11:20 Session 3 – Case studies – Enhancements to workflow and calculations

  • Problems in assessing flare capacity limitations, location of maximum vessel stresses and managing data
  • Reducing uncertainty in calculations before changing RO sizes or consideration of Passive Fire Protection
    • Case study 1: HP separator fire analysis
  • Introducing more efficient and consistent calculations
    • Case study 2: Finger type slug catcher blowdown strategy
12:30 Lunch
More Information
Full utilisation of the flare system capacity by fast depressurization should be aimed for in order to prevent unacceptable escalation and to minimise the use of PFP.