Leveraging process safety to optimise capital project risk reduction and cost
04 October 2021
While the sustainable energy market boom is attracting most international headlines, the petrochemical market, which supports nearly 2 million jobs worldwide, continues to quietly expand to meet growing demand (Figure 1). The petrochemical market forms a key part of Europe’s economy with new facilities such as the INEOS Project One in Lillo, Antwerp that is being called the most energy-efficient ethylene cracker in Europe.
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Capital projects supporting this ongoing expansion and renewal can be as complex as a greenfield processing facility or as simple as a new building or operational debottlenecking. Process safety is one of many areas to be addressed within the lifecycle of a capital project, however it is still all too common for process safety reviews to be conducted only once the design and site layout have reached a mature state. At this advanced stage of design, mitigating hazards and risks is either difficult, costly, time consuming or a combination of all three due to the high level of rework with risk mitigation associated with efforts such as relocating hazards and populations to safer locations, adding layers of protection to design systems, and ensuring the buildings are robust enough to protect personnel from the identified hazards.
One way to mitigate this is to utilise stage gate process safety reviews throughout the design phases that align with the overall project stage gate schedule so they provide timely results and recommendations that can flow into the design process prior to the next stage. The CCPS book ‘Integrating Process Safety into Engineering Projects’ covers in detail the proactive implementation of process safety activities at the optimal time as well as conducting reactive reviews to provide assurance nothing significant has been missed. Through the early application of process safety design reviews, capital projects can optimise designs that meet geographic constraints and corporate safety goals around optimising risk reduction while minimising project and facility lifetime cost impacts.
In short, having a safety plan that starts at the onset of a capital project may take more time, effort, and investment early on in the project lifecycle, but the savings in preventing costly schedule impacts, cost increases, and frustration later in the project are well worth the investment.
Capital project stages
The main capital project stages are presented in Figure 2. The terminology may differ between publications and companies, for example Front End Loading (FEL) may also be referred to as Front End Engineering Design (FEED).
The objectives of each stage from the business perspective can be described as follows, noting that for smaller or expedited projects, two or more of the design phases may be combined.
1. Appraise FEL-1: A range of development options are identified and commercial viability is evaluated.
2. Select FEL-2: Selection for the site layout based on evaluation of threats and uncertainties.
3. Define FEL-3: Development of a basic design including preliminary plot plans and equipment layout drawings; preliminary process flow diagrams (PFDs); heat, material, and energy balance sheets (HMBs); and equipment data sheets.
a. This stage also improves on cost and schedule and the project typically receives financial approval.
4. Detailed Design: Detailed engineering of option chosen in FEL. Procurement of materials and equipment commences.
5. Construction: Facility is built, pre-commissioning is completed, and operational readiness is performed.
6. Startup/Commissioning: Facility and documentation is handed over to the operations company / team from the project team.
7. Operation: Facility handed over completely to operations team, normal operations continue, and project closed.
8. End of Life: Facility is decommissioned or repurposed.
Figure 1 – Production of Key Thermoplastics, 1980-2050 – Source: IEA, Production of key thermoplastics, 1980-2050, IEA, Paris https://www.iea.org/data-and-statistics/charts/production-of-key-thermoplastics-1980-2050
At the onset of the Appraise FEL-1 phase, a safety plan should be created that lays out the strategy and schedule of process safety activities over the project lifecycle. This plan should be a living document, updated as needed throughout the project lifecycle as project clarity is established. Process safety studies are often viewed as negatively impacting each phase of a project in terms of cost and schedule. Effectively managing this misguided perception is essential for seamless integration between the owners of the technical safety plan and the engineering design.
Technical safety studies in capital projects
Depending on the capital project specifics, there is a range of technical safety studies commonly used to identify hazards as well as assess and mitigate risk throughout the project lifecycle. The following paragraphs provide an overview of a stage gate review process for optimising key aspects of the site safety plan including site layout and spacing, fire protection (passive and active), emergency response, occupied building siting, and future construction and turnaround planning. Hazard Identification and Risk Analysis, e.g., PHA/HAZOP/LOPA, is not specifically addressed as the hazard review has become an expected deliverable.
Many of these technical safety studies are interconnected and each has an optimal time in the project lifecycle to be performed to the level of detail best suited to available project data. As later phases introduce increasingly detailed levels of engineering data, several of these studies should be revisited and documented to reflect the accumulative level of detail.
Site layout and spacing
Site layout and spacing is undertaken in the very earliest stage of capital projects, Appraise FEL-1, when conceptual and feasibility reviews are ongoing. Multiple locations and layouts are reviewed to minimise both risks and costs to the project. At this stage, previous lessons learned with regards to layout and spacing should be reviewed and should cover environmental factors such as weather and sensitive areas, topography, access, and exposure of neighbouring populations. Focus should be placed on inherently safer design (ISD) and lessons learned from historical incidents.
Once Appraise FEL-1 is complete, the refinement of the site layout and spacing naturally embeds within the review of other technical safety studies. Significant changes after this are likely to have significant cost and schedule impacts.
Figure 2 – Typical capital project stages
Fire protection (passive and active)
Passive and active fire protection reviews are likely to include Fire and Gas Detection (F&G), Fire Hazard Analysis (FHA), and Fire Water (FW) analyses. Preliminary fire protection studies are typically experience and best practice based, drawing on available industry guidance and corporate philosophy documents. Paired with the most recent plot plans and preliminary risk analysis studies, preliminary fire protection studies should be conducted during Select FEL-2.
At this stage, general design considerations and philosophy documents are reviewed to develop a cost-effective fire protection strategy that includes a preliminary layout of detection, passive fire proofing, and active water spray and drainage systems. Firewater systems should be designed during FEL-2 based on maximum demand calculations and be verified during later project stages; however, defining at this stage allows for supply, distribution, pumps, fixed/mobile systems, foam, drainage requirements, etc. to be estimated for purposes of preliminary layout and cost analysis.
During the Detailed Design phase of the project, the F&G, FHA, and FW studies (collectively the Fire Protection study) should be updated to reflect the detailed engineering design information. At this phase of the project, the philosophy documents and the proposed location and types of equipment (detectors, monitors, deluge, foam systems, etc.) are finalised. A desktop fire scenario review should be conducted based on information from the quantitative risk assessment (QRA) to determine and validate maximum firewater demands to finalise the design for the firewater system.
Emergency response plan
A detailed emergency response plan (ERP) is an essential technical safety study and requires input from a wide variety of supporting technical safety studies, as shown in Figure 3. Reliance on input from other safety studies means the establishment of an ERP in the FEL stages of a project is not a good use of resources due to the ongoing adaptations to the project data. However, by the detailed design phase, project data has reached a stage at which an ERP can usefully be developed.
During the Operations phase, the ERP should be revisited; typically on a 5-year revalidation cycle or when changes occur.
Occupied building siting
Figure 3 – Example ERP key components and supporting studies
Occupied building siting is part of the risk analysis, which should first be reviewed during Appraise FEL-1 in conjunction with the site layout and spacing review. The conceptual risk assessment at this phase should be a high-level review that involves the evaluation of significant Health, Safety, and Environment (HSE) issues that could impact the project. In addition to reviewing layout and spacing, this also includes addressing key issues such as location, technology, process units, etc. with the ultimate outcome being a risk ranking of available options.
Typically, at Select FEL-2, general plot plans are available but fluctuating to address identified issues in early technical safety studies. In addition, general unit information in the form of material lists and block flow diagrams is available but detailed engineering process data is not yet available. Preliminary risk analysis is conducted using industry experience with similar units and is typically looking at order of magnitude and catastrophic risk drivers.
By Define FEL-3, a plot layout has been selected, preliminary equipment layout drawings and equipment lists are available, as well as preliminary process data and piping and instrumentation diagrams (P&IDs). With the availability of this information, the preliminary risk assessment should be conducted at the transition between the Select FEL-2 and Define FEL-3 stages with the preliminary QRA occurring in the Define FEL-3 stage. The preliminary QRA is based on information detailed enough that initial “what-if” mitigation exercises can be undertaken, and safeguards planned for prior to detailed engineering.
The preliminary QRA can then be easily updated during the Detailed Design to accommodate new information as it becomes available. This phase of the project should identify and address potential issues with selected plant layout, location of occupied buildings, hazard resistance of key occupied buildings, and mitigation system design. At this point, refinement of the QRA is such that only minor changes should be needed to reflect normal operations during the Operational phase of the project.
As with the ERP, the QRA should be subject to review and revalidation both on a periodic basis and as part of a Management of Change process to reflect site expansion/demolition, staffing changes, process changes, etc. throughout the facility lifecycle.
Future construction and turnaround planning
Once the QRA is “finalised” in terms of the model (site layout, input data, estimated occupancy, etc.), it can be applied to construction and turnaround risks.
During the Construction and Commissioning stages, different units will come online in sequence with a higher-than-normal operations population distribution. Also, depending on the capital project location, hazards from existing neighbouring facilities may be present and pose similar/unique site challenges. A properly conducted QRA can accommodate these various configurations to provide a picture of risk during the Construction phase of the capital project. Special care should be taken to ensure that temporary work locations such as portable buildings and blast resistant modules (BRMs) are included in the analysis to ensure construction teams are protected to an acceptable risk level.
Robert Magraw, BakerRisk
When conducting turnarounds during the Operation stage, the hazard profile at the facility changes (i.e., units taken down) and populations increase. In addition, temporary buildings are often located both near and far-field to accommodate turnaround populations. In a turnaround QRA, the focus is on ensuring that personnel are located in areas that are within acceptable risk criteria and that risks, where possible, are minimised to ensure safe turnaround operations.
As the petrochemical industry continues to expand to meet increasing societal demand for products and the drive for more efficient and sustainable operations, capital projects large and small continue apace.
Conducting technical safety studies early, based on the available details, and throughout the capital project process ensures changes in design are more palatable and cost efficient. Embedding the safety plan within the overall stage gate review process achieves the overall goal of minimising risk while controlling costs and schedule impacts ensuring successful project implementation. As stated earlier, having a safety plan that starts at the onset of a capital project may take more time, effort, and investment early on in the project lifecycle, but is well worth the investment.
About the author:
Robert Magraw is the Operations Manager of BakerRisk Europe Ltd. He has an extensive career of over thirty years in safety and risk management, including twelve years in the oil, gas, and petrochemical sectors and over eighteen years in the nuclear industry. His main areas of technical practice currently include PHA, SIS/SIL, QRA, audit, insurance risk engineering, and management system development. He was previously head of environment, health, safety, and quality for an international nuclear services company. He also managed the corporate HSE management system and assurance program for a major international nuclear business with a global portfolio of nuclear and non-nuclear operations. Mr. Magraw is a member of IChemE Hazards Technical Committee and the European Process Safety Centre Technical Steering Group. He is also a TUV certified functional safety engineer.