gFLARE: PSE's Oil & Gas technology
Industry-leading depressurisation and dynamic flare analysis software
gFLARE® is a flare network and depressurisation modelling platform used by PSE to provide advanced process safety analysis services. It combines the powerful dynamic simulation and optimisation technology of the gPROMS platform with PSE's industry-leading high-fidelity flare network and depressurisation models. gFLARE addresses many different dynamic simulation challenges within a single comprehensive framework.
With gFLARE, it is possible to:
- perform all standard steady-state flare design calculations
- use dynamic simulation to determine the effects of flare network holdups ('packing')
- establish the scope for reducing total flare load via staged relief
- combine the flare system and upstream process
- determine where and when hydrate and ice formation may occur
- perform full 2-D and 3-D metal temperature modelling for critical areas of piping and equipment
- calculate directly quantities of operational interest such as remaining flare margin.
Advanced depressurisation: the dynamic difference
Conventional flare network design techniques use many simplifying assumptions. Dynamic events are treated as steady-state. Distributed systems are lumped into pseudo-vessels. Complex thermodynamics are simplified to accommodate legacy software. All of these assumptions give rise to incorrect results. At best, they are conservative, leading to over-design and unnecessary CAPEX. In many cases, however, results are non-conservative, giving rise to a real danger of failure.
To make accurate, precise predictions, gFLARE incorporates the following industry-leading techniques:
Despite the fact that pressure-relieving events are inherently dynamic, conventional flare network design techniques use peak relief flows in steady-state simulations to assess system capacities and to determine back-pressures downstream of valves, Mach number in the headers and radiation at the flare tip. gFLARE is fully dynamic and avoids these specious assumptions.
Realistic volume representations
Every vessel or valve in a system experiences different conditions, but conventional approaches lump them together in a single pseudo-vessel. gFLARE's distributed analysis represents each segment explicitly. This allows the analysis to pinpoint potential problem segments and test mitigation strategies within the simulation.
Depressurisation is fast. There is no time for vapor and liquid phases to reach equilibrium, but conventional practices assume just that. gFLARE's rigorous, rate-based thermodynamics predict accurate temperatures even when liquid condensation occurs.
Detailed fluid / metal heat transfer
Materials of construction decisions demand accurate metal temperatures. Blowdown segments may contain large diameter vessels, large and thin bore pipes and heat exchangers - these all have different heat characteristics, heat transfer areas and metal mass. gFLARE's detailed heat transfer models give engineers clarity with precise information on locations of embrittlement risk.
Coupled process and flare
For a blowdown operation, common practice performs separate depressurisation calculations and then uses the results as an input to the steady-state flare calculations. This outdated method largely ignores flare back-pressure controllers, sequenced blowdown processes and low pressure sources. gFLARE's fully coupled process and flare models incorporate all of these effects with a realistic representation.
Hybrid modelling with CFD
Sometimes in order to perform complex analysis, it is necessary to combine the best available technologies. In separator cold spot analysis, complex flow patterns are best done in CFD while equilibrium phase changes are best modelled in gFLARE. PSE's hybrid modelling interfaces – in collaboration with industry leaders such as ANSYS FLUENT – are designed for just this type of analysis.
Advanced technology validated in the real world
gFLARE is extensively validated against experimental data as well as data for the blowdown of full scale Oil & Gas facilities. Validation comparisons include:
- Pilot scale measurements including metal temperatures from published data (Haque, et al.)
- Full facility blowdown measurements for four systems from two different operating companies including offshore and onshore facilities
- Flowline blowdown data for two systems
- Client benchmark results including:
- 21 systems for six clients
- System sections including compressors, slug catchers, TEG contactors, separators, manifolds and more
In all cases, gFLARE has outperformed other available technology. As a result, gFLARE is an approved technology for more than 15 operating companies including four supermajors and multiple large national oil companies.
Since January 2011, gFLARE has been used in hundreds of process safety analysis projects on more than 65 different facilities (existing or under design). Projects range from a single blowdown assessment to full facility analysis. Our case studies demonstrate real projects with savings in the hundreds of millions of dollars and reduced safety risks.
Effective software built to integrate with your workflow
Making use of a high-fidelity modelling approach requires seamless integration with your workflow. To that end, gFLARE has been developed so that existing models from conventional analysis tools can be quickly replicated in gFLARE architecture, ensuring analysis occurs in a timely fashion.
gFLARE is also useful when limited data is available, for example during pre-FEED. Utilising known feed gas composition, anticipated pressure, and general characteristics of equipment and vessels, PSE can ensure early design ideas always progress towards the goal of maximum safety with minimum CAPEX.
gFLARE is built on the gPROMS platform, the powerful equation-oriented modelling and optimisation framework on which all of PSE's gPROMS family products are built. The gPROMS platform provides drag & drop flowsheeting, parameter estimation, physical properties integration, powerful optimisation capabilities that allow direct calculation of optimal solutions rather than by trial-and-error simulation, plus many other features.
These capabilities enable gPROMS family products to go well beyond existing process modelling tools, providing a new generation of advanced applications that enable you to create competitive advantage as never before.