Elixir Engineering of Oman was awarded to perform detailed engineering and Technical safety studies for Risk assessment and implement appropriate measures to manage them effectively. The aim is to optimise production while ensuring safety through comprehensive Hazard identification and Mitigation strategies.
The objective of this project is to reduce the backpressures and increase the production to know the hidden potential before going for full field development of the field.
PDO (Petroleum Development Oman) have plan to start production from 4 new wells in Marmul West (MMW) field & 1 No. from Amjad field in Oman. These wells are highly viscous oil wells with API gravity of 20 and water cut of zero. Since the viscosity of oil is very high it has safety procedures have been proposed to dilute with the water to reduce the oil viscosity and make the flow-able. The safety measure approach is to reduce the fluid viscosity. Oil has the tendency to form emulsions (mixture of two liquids that usually don't mix well together) with water. The emulsion viscosity increases with increase in water cut up to the inversion point. However, on further addition of water the fluid viscosity is equal to the continuous phase i.e. water. By adding water to the oil to cross the inversion point; the mixture viscosity shall be reduced thereby reducing the backpressures.
In absence of LAB data i.e. emulsion viscosity curves, it has been decided to maintain water cut at 70% and viscosity of continuous phase has been considered for the calculation. Under this project, various options for adding water to gross having no water are studied and most appropriate/workable/optimized option is selected based on steady state hydraulic calculation criteria.
Amjad Field
MMW Field
The engineers of Elixir Engineering have conducted the listed technical safety studies for the Amjad and MMW (Marmul West) Hookup project in Oman, focusing on comprehensive Hazard identification and Mitigation strategies.
The process of dividing a facility into hazardous and non-hazardous sections and then further subdividing the hazardous parts into zones is known as area classification. A three-dimensional place that requires extra care in Hazardous equipment design and construction hazard assessment as well as in controlling other potential ignition sources is known as a Hazardous Area Classification (HAC). This is because flammable atmospheres are expected to be present there at certain frequencies.
Zone Classification: Zones are created inside hazardous locations according to the probability and length of a flammable atmosphere.
Zone 0: The area of a dangerous area when there is a constant or prolonged presence of combustible air.
Zone 1: The portion of a dangerous location where the likelihood of a hazard flammable environment during regular operations is high.
Zone 2: The portion of a flammable hazard sign location where there is little chance of a flammable environment during regular operations and, in the event that it does, it will only last briefly.
Non-hazardous areas: Regions not covered by any of the aforementioned categories.
Source and grade of release: Any location from which a flammable gas, flammable vapour, or flammable liquid may be released into the atmosphere is considered a source of release for the purposes of area categorisation. The expected frequency and duration of three grades of release are defined. Continuous grade release: A release that happens often and at brief intervals, is virtually continuous, or is both. Primary grade release: A release that is planned for in operating procedures, meaning it is one that is expected to happen on a regular or infrequent basis during normal operation. Release classified as secondary grade: One that, in any case, will only happen seldom and for brief periods of time and is unlikely to happen during regular operations.
Fluid Categories
| Fluid | Description |
| A | A combustible liquid that would quickly and significantly evaporate upon discharge, This category includes: (a) Any liquefied petroleum gas or lighter flammable liquid. (b) Any combustible liquid that has reached a temperature high enough to yield more than 40% volume vaporisation upon release and no external heat input. |
| B | A flammable liquid that does not fall under category A yet is hot enough to boil when released. |
| C | An ignitable liquid that does not fall under category A or B but that, upon release, may reach a temperature higher than its flash point or condense into a flammable mist or spray. |
| G(i) | A typical methane-rich natural gas. |
| G(ii) | Refinery hydrogen. |
By identifying and assessing potential fire and explosion hazards, the FGDEA seeks to ensure that the facility layout minimizes the probability of escalation to the greatest extent that is practically practicable. According to PDO SP-1258 (Quantitative Risk Assessment Specification), Physical Effects Modeling (PEM) is used to assess the impact of credible leaks and ascertain the likelihood of escalation. According to the probable sources of leakage (PSLs), the study assesses the physical effects of hydrocarbon emissions as well as the possibility of harm to workers from flammable and hazardous releases.
As far as is practical, the physical effects modelling completed as part of the FGDEA will be used to optimise the Hook-Up Project, mitigate escalation, and create an intrinsically safe plot based on PDO SP-1127 & SP-1190. It will also be used to confirm that the current Maintenance drain pit vent pipe layout is appropriate in accordance with DEP 80.45.10.10-Gen requirements.
Elixir Engineering was awarded to perform providing Thamoud West and Maurid NE fields necessary infrastructure / surface facilities to accommodate gross production demand according to the latest forecast and proposed FDP.
Maurid field which is split between Maurid (Main) & Maurid North East fields, is located on the eastern side of the South Oman salt basin NE of Salalah. Maurid North East (MDNE) field was discovered late 1997 with wells MDNE-1 and MDNE-2 discovering oil in the MG & LG and was brought on-stream in 1998.
Thamoud field which is split between Thamoud West and Thamoud East fields, is also located on the south-eastern margin of the South Oman salt basin. Maurid NE and Thamoud west fields are currently produced under waterflooding. The main producing reservoir associated with Maurid NE field is Ghariff formation and for Thamoud west field these are Ghariff and Al Khlata formations.
Scope of Work
The Project scope is listed below,
MSVs, CS+HDPE liner/rotoliner MSVs to existing Manifold, Coriolis Meter + WC meter (Red Eye), 300# for well testing with Static Mixer and provision for Prover, common provision for Mobile Well Testing (PI Unit), Provision for future installation of static mixer and WC meter, concrete closed Relief/Maintenance Pit with Level transmitter, partial RVs (1W+1S), Demulsifier skid with Demulsifier storage tank in Manifold, RTU for the Demulsifier Skid, full flow RV on the test header.
The Scope of Elixir Engineering is to perform the listed safety studies for Thamoud Infill Phase-3 project.
The process of dividing a facility into hazardous and non-hazardous sections and then further subdividing the hazardous parts into zones is known as area classification. A three-dimensional place that requires extra care in equipment design and construction as well as in controlling other potential ignition sources is known as a hazardous area classification (HAC). This is because flammable atmospheres are expected to be present there at certain frequencies
Zone Classification: Zones are created inside hazardous locations according to the probability and length of a flammable atmosphere.
Zone 0: The area of a dangerous area when there is a constant or prolonged presence of combustible air.
Zone 1: The portion of a dangerous location where the likelihood of a flammable environment during regular operations is high.
Zone 2: The portion of a hazardous location where there is little chance of a flammable environment during regular operations and, in the event that it does, it will only last briefly. Non-hazardous areas : Areas that do not fall into any of the above.
Source and grade of release: Any location from which a flammable gas, vapour, or liquid may be released into the atmosphere is considered a source of release for the purposes of area categorization. The expected frequency and duration of three grades of release are defined.
Continuous grade release: A release that happens often and at brief intervals, is virtually continuous, or is both. Primary grade release: A release that is planned for in operating procedures, meaning it is one that is expected to happen on a regular or infrequent basis during normal operation.
Release classified as secondary grade: One that, in any case, will only happen seldom and for brief periods of time and is unlikely to happen during regular operations
Fluid Categories:
| Fluid | Description |
| A | A combustible liquid that would quickly and significantly evaporate upon discharge, This category includes: (a) Any liquefied petroleum gas or lighter flammable liquid. (b) Any combustible liquid that has reached a temperature high enough to yield more than 40% volume vaporisation upon release and no external heat input. |
| B | A flammable liquid that does not fall under category A yet is hot enough to boil when released. |
| C | An ignitable liquid that does not fall under category A or B but that, upon release, may reach a temperature higher than its flash point or condense into a flammable mist or spray. |
| G(i) | A typical methane-rich natural gas. |
| G(ii) | A typical methane-rich natural gas. |
By identifying and assessing potential fire and explosion hazards, the FGDEA seeks to ensure that the facility layout minimizes the probability of escalation to the greatest extent that is practically practicable. According to PDO SP-1258 (Quantitative Risk Assessment Specification), physical effects modeling (PEM) is used to assess the impact of credible leaks and ascertain the likelihood of escalation. According to the probable sources of leakage (PSLs), the study assesses the physical effects of hydrocarbon emissions as well as the possibility of harm to workers from flammable and hazardous releases. As far as is practical, the physical effects modeling completed as part of the FGDEA will be used to optimize the Dhiab Infill Development Project, mitigate escalation, and create an intrinsically safe plot based on PDO SP-1127 & SP-1190. It will also be used to confirm that the current Maintenance drain pit vent pipe layout is appropriate in accordance with DEP 80.45.10.10-Gen requirements
The objectives of this study is to
The overall study approach is summarised as follows
Any piece of hardware, structure, system, or logic software whose malfunction could result in a Major Accident Hazard (MAH) or whose goal is to stop, limit, or lessen the impacts of an MAH is referred to as a Safety Critical Element (SCE).
The identification of the Safety Critical Element (SCE) represents a critical step in project development that aims at minimizing the Major Accidental Hazards (MAHs) occurrence; this activity has to be performed from the beginning of the project and updated coherently with the developments throughout the life cycle of the project.
The aim of the present document is to provide the methodology used for the identification of SCE and eventually brief up the identified SCEs for the project. In order to identify the SCE, the basic principle followed is as given below:
The role of a preventive / mitigation barrier is to prevent threat and limit consequences of MAH. The purpose of this section is to ensure that all hardware barrier which are necessary to control MAH, are identified and the relevant SCEs are tabulated along with the tag No.
Hardware Barrier
High level grouping of SCEs utilized for reporting reasons is one of the hardware obstacles for MAH. There are 8 types of hardware barriers as depicted in the “Swiss Cheese Model”, shown the following figure - 2: Hardware Barrier and SCE Groups, which represents the two sides of bow-ties.
The hardware barriers are depicted with a number of small holes that represent a design flaw or some potential degradation of their performance. On their own, these degradations may not be significant but, if the holes line up, there may be no effective barriers in place between safe operations and escalating consequences, leading to MAH.
SCE Groups
Hardware barriers are separated into SCE Groups for the purpose of management and reporting. The role these Groups play in maintaining the barrier's integrity defines them.
SCE Selections
In general, the process of selection of SCEs start with a review of the generic list of SCEs as per the standards. SCEs selection process as represented below.
HFE Design Verification (Define phase)
Design shall be reviewed to verify that it complies with the project HFE Design Verification HFE standards as defined in the project technical standards selection list and any HFE requirements identified through HFE studies conducted in the combined DEFINE and EXECUTE phases have been satisfied.
HFE Construction Verification (Execute phase)
Ensure that HFE requirements have implemented at site during construction phase as per recommendations from design verification, if any.
The verification review shall be done by the project HFE Authorized person and appropriate disciplines wherever applicable in line with SP-2215-1 Human Factors Engineering in projects – General Requirements.
HFE shall be initiated in the assess phase of projects, Figure 4 gives an overview of the HFE Activities in each of the ASSESS, SELECT, DEFINE and EXECUTIVE phase of the project life cycles.
Elixir Engineering was awarded to perform to ensure safety and optimise production with comprehensive Onshore Depletion and Compression Enhancements at the Musandam Gas Plant (MGP)
The Bukha Alpha platform is located roughly 23 kilometers from the Musandam Gas Plant (MGP), and the Bukha Field is located in Block 8 about 23 km offshore from the western coast of the Musandam Peninsula. The Bukha and West Bukha oilfield are located in Offshore Block 8, which produced 4,458 barrels of oil equivalent per day on average in 2018. As of January 2019, MOGC (Musandam Oil and Gas Company), which is wholly owned by MOGC (OQ E&P LLC), is in charge of operating Block 8.
The Musandam Gas Plant ("MGP"), an onshore processing plant, handles all of the production from Block 8. Whereas downstream gas processing units need an optimum operating pressure. The MGP's inlet arrival operating pressure is in optimum condition. The three inlet compressors located downstream of the slug-catcher are utilized to increase the pressure to the required pressure. It is necessary to maintain the compressor setup such that one compressor is kept in standby mode.
Presently, in order to achieve the required inlet pressure at MGP, the wells at Bukha and West Bukha are being operated at nominal pressure. Production wells are in depletion mode, generating primarily gas and a lesser amount of water and condensate. It is suggested that the MGP plant intake be operated at a lower pressure rate in order to improve production there. As part of the conceptual study, various configurations of inlet gas compressor arrangements were examined in order to support the aforementioned proposal, and option 3A configuration was determined to be a workable choice.
In order to combine the project scope with the current plant for the reduced operating pressure at the slug
Production wells are in depletion mode, generating primarily gas and a lesser amount of water and condensate. It is suggested that the MGP plant intake be operated at a lower pressure rate in order to improve production there. As part of the conceptual study, various configurations of inlet gas compressor arrangements were examined in order to support the aforementioned proposal, and option 3A configuration was determined to be a workable choice. In order to combine the project scope with the current plant for the reduced operating pressure at the slug catcher inlet, the following change will be necessary.
After the particle filter/coalescer, new piping must be tied in downstream to route the gas to the new LP compressor suction via an LP suction scrubber. In order to meet the current gas compressor inlet parameters, gas pressure must be increased at the LP compressor inlet. To fulfill the project's requirements, the current inlet gas compressor arrangement must be modified to (1W+2S). In accordance with current circumstances, gas pressure has been increased to satisfy the GSU battery limit requirement.
After the slug catcher condensate common line, a new tie-in must be created to integrate the new condensate booster pump. Condensate operating pressure has been raised to match the existing operating pressure at downstream. Produced water from the slug catcher is re-routed to the existing skim system instead of connecting downstream due to the low operating pressure of slug catcher.
A new tie-in shall be made to provide fuel gas blanketing for MP production separator with the required operating pressure due to limitation of fuel gas supply pressure at downstream & constant supply to the pre-flash vessel in order to keep the necessary operational pressure.
The EPC scope of work includes the Engineering, Procurement, Manufacture, Fabrication, Logistics, Supply, Construction, Installation, Erection, Managing Interfaces, Interconnection, Supervision, Training< Pre-commissioning, Commissioning, Start-up, Testing and completion of the facilities; performing warranty and remedial work concerning the facilities, the provision of spares, and the provision of As built, Asset registration all document required for final acceptance of the work and project hand over including arrangement of temporary facilities.
The following actions are part of the work, but they are not the only ones:
Following major equipment/modification anticipated:
In context to the above scope of work, Elixir Engineering has done below listed safety studies for the Brownfield modification project for Onshore Depletion- Compression at MGP.
The Escape, Evacuation, Mustering and Rescue facilities include the following
Escape, Evacuation & Mustering Study Methodology
The EER approach recognises that there are many potential Major Accident Hazard scenarios, which may require EER. The Major Accident Hazard scenarios will be assessed for their potential to impair the escape, evacuation and rescue systems. The study involves an assessment of EER systems with regards to the egress, escape, evacuation and rescue goals and impairment criteria. A review of each process area will be undertaken to determine whether the escape routes and muster locations can be impaired under impact from MAHs. The purpose of this review is to determine whether the provided EER facilities are adequate or any additional EER systems are required.
Time required to escape and muster to the Muster areas will be estimated in this study. The estimated time will be used to determine the minimum criterion for which the Muster areas are required to maintain their integrity (endurance time). The EER arrangement availability and effectiveness will be assessed under the various MAH scenarios.
The following Methodology will be followed for the EERA study
MAH Scenario Identification
The development of Major Accidents from consideration of the Major Accident Hazards (MAHs) present at the facility must be clearly identified.
The objective of F&G Mapping study is to ensure F&G detectors are distributed in line with the F&G philosophy of project based on Fire & Gas Detector Layout, Identify any gaps and to make recommendations where required on the number and placement of various detectors.
Fire & Gas detection
Prompt detection of gas release or a fire at its earliest stage of development is a crucial factor for a fire protection system to be effective, with a rapid response minimizing the potential for the event to escalate. A good fire & gas detection system gives detection provisions aligned with the hazards presented across the facility, providing a response that minimizes the impact of releases to personnel, assets, and the environment. Detection can take place by personnel or by safeguarding instruments, with instrument detection systems that includes the following:
The nature of the response is typically defined in the facility’s Fire & Gas philosophy, that depends on the risks associated with the facility, the detection systems can be used to either provide an alarm requiring personnel action and/or to initiate executive actions, such as plant isolation automatically.
Methodology:
Step 1: Hazardous Area Identification - The Musandam Gas Plant (MGP) will be critically assessed for identifying all hazard (fire and gas (flammable & toxic) hazards) areas that are present will be segregated into different hazardous detection areas /Mapping areas.
Step 2: Hazardous Area Characterisation - From the above identification, major accident hazards will be characterized based on the likelihood and frequency of the incident related to the properties of the fluid and quantity of the fluid released.
Step 3: Risk Volume Definition - The Risk Volume will be defined for the identified hazardous area in line with company/International standards/Good Engineering Practices.
Step 4: Identifying the distinctive cloud for detection - The Risk Volume will be assessed and the cloud size for detection will be identified in line with company/International standards.
Step 5: Detect 3D Modelling - The 3D Geometry file will be imported to the software and the Fire and Gas detectors will be placed based on preliminary F&G Layout at the hazardous zone.
Step 6: Coverage Mapping - The newly installed detectors in the layout will be evaluated in accordance with the performance target to determine whether or not they are positioned appropriately to sense and identify any potential fires and gas dispersion at that site.
Step 7: Optimization/Detector Layout Definition - For each loss of containment scenario, use the same procedures as above. If the detectors are discovered to be insufficient to sense or detect the dispersion, adjust the height of the detector or move its placement to better align with the hydrocarbon release's dispersion coverage.
The key objectives of FERA study are as follows:
Methodology
A systematic and organized method for determining and evaluating the risks associated with fire and explosion threats is called Fire and Explosion Risk Assessment, or FERA. To guarantee safe facility layouts, the assessment's findings are used as inputs to fire zone assessment, specify active and passive fire protection system requirements assessment, and provide inputs for escape, Evacuation and Rescue Assessment (EERA), Occupied Building Risk Assessment (OBRA), and Quantitative Risk Assessment (QRA) studies. FERA will assess the fire and explosion scenarios for Brownfield Modification Project for Onshore Depletion Compression at Musandam Gas Plant (MGP).
For the Brownfield Modification at MGP, the FERA shall involve the following major steps
The key objectives of PEM study are as follows
Methodology
Physical effect modelling (PEM) is a structured and systematic process to identify and assess the impacts from fire and explosion hazards. The evaluation's findings are applied to guarantee secure facility designs.
Elixir Engineering was awarded to perform Safety Integration and Valve Criticality Analysis for Dhiab Infill Development Project
Dhiab Field is located 35km SW of the Marmul Field, onshore Oman in the South Oman Salt Basin. The field was discovered in 1985 and first oil was produced to surface in 1987. Dhiab structure is essentially a four-way-dip anticline, complicated by significant faulting.
The field is currently produced under water flooding, a mini water flooding experiment started in 2012 to test the response to flank water injection as a mean to increase field recovery, given the overall absence of strong aquifers to support pressure. The 2016 FDP suggested WF 5-spot development as the development mechanism which is implemented in the field since 2017. The main producing intervals in Dhiab are Middle Gharif, Lower Gharif and Al Khlata Formations, with total STOIIP of 16 million Sm3 as per 2016 FDP.
2016 saw the delivery of Dhiab's most recent FDP. Phase II development was covered. The development has a total of 48 2PUD wells. Inverted "9-spot" patterns, which are part of the CR project, and inverted 5-spot patterns with 250 m spacing for 2PUD.
As per June 2021 the cumulative oil production is ~ 1.44 MMm3, with expected developed and undeveloped reserves of ~ 0.54 MMm3 and ~ 0.57 MMm3 respectively. The total STOIIP expected was estimated at ~ 16.96 MMm3, yielding an expected recovery factor of 21% (currently around ~ 15%). The major items covered under this project scope are listed below, Project scope will be executed in 2 phases
Phase 1
Phase 2
Elixir Engineering has done the listed safety studies for Dhiab Infill project.
The process of Hazardous Area Classification (HAC) involves determining which elements of a facility are dangerous and which are not, as well as creating zones for the hazardous areas. A hazardous region is described as a three-dimensional place where it is reasonable to assume that a flammable atmosphere will exist at frequencies that necessitate particular safety measures for equipment design and construction as well as the management of other possible ignition sources.
Zone Classification: Zones are created in hazardous regions according to the probability and length of a flammable atmosphere.
Non-hazardous areas : Areas that do not occupy any of the above.
Source & Grade of release: Any region from which a flammable gas, vapour, or liquid may be discharged into the atmosphere is considered as a source of discharge for the purpose of area segregation. Based on their expected frequency and duration Three release grades are recognised.
Fluid Categories
| Fluid | Description |
| A | A flammable liquid that would quickly and significantly evaporate upon release. This group consists of: (a) Any lighter flammable liquid or any liquefied petroleum gas (b) Any flammable liquid at a temperature high enough to cause more than 40% volume to evaporate upon release when released, with no additional heat input from the environment. |
| B | A combustible liquid that isn't in category A yet is hot enough to boil when released |
| C | A flammable liquid, not in categories A or B, but which can, on release, be at temperature above its flash point, or form a flammable mist or spray. |
| G(i) | A typical methane-rich natural gas. |
| G(ii) | Refinery hydrogen. |
The goal of the FGDEA is to guarantee that the facility layout minimizes the possibility of escalation to the greatest extent that is practically practicable by identifying and evaluating plausible fire and explosion dangers. To evaluate the impact of believable leaks and determine the possibility of escalation, physical effects modeling (PEM) is used in accordance with PDO SP-1258 (Quantitative Risk Assessment Specification). The study evaluates the potential for impact on workers from hazardous and flammable releases as well as the physical impacts of hydrocarbon emissions, as specified by the potential sources of leakage (PSLs). The physical effects modelling carried out as part of the FGDEA will be used to optimize the Dhiab Infill Development Project and to mitigate escalation and achieve an inherently safe plot, as far as practicable, based on PDO SP-1127 & SP-1190 and confirm the suitability of the current layout of the Maintenance drain pit vent pipe based on the requirements in DEP 80.45.10.10-Gen.
The objectives of this study is as follows:
The overall study approach is summarised as follows:
Hazard Identification
HFE-VCA's goal is to outline the requirements for applying HFE concepts to valve design and layout, which includes the following:
Valve Criticality Rating
General
Valves are rated by criticality to help ensure that criticality valves are located to provide for rapid and effective identification and operation. The following three categories are recommended. Risk to health and safety—including the possibility of human error—must be maintained to a minimum.
Category-1 (C-1) Critical Valves
Included in the category of valves are those necessary for regular or emergency operations where quick and unhindered access is crucial. The next sections' descriptions of the "preferred" site must be followed in terms of height, reach distances, and visibility.
These valves satisfy any or all of the subsequent requirements:
Access Requirement for C-1 Valves
A permanent raised standing platform must be made available for accessibility. If steps are the only feasible means of access to the elevated platform, then access at ground or deck level is permissible.
The identification and state of valves must be easily observable from an approachable operator position, such as on a nearby walkway, access platform, or in the area surrounding equipment meant for human use.
Category-2 (C-2) Non-Critical Valves
Valves are employed in routine maintenance and inspection procedures, but they are not essential for regular or emergency operations. These valves satisfy any or all of the subsequent requirements:
Access Requirement for C-2 Valves
The "preferred" location, as shown in Figures 2 and 3, for C-2 valves should be the same as for C-1 valves in terms of height, reach, and visibility. C-2 valves may be located within the “acceptable area” as outlined in Figure 3, depending on their size and the force needed to operate them. A vertical fixed ladder and a small standing surface must be provided for access to C-2 valves in cases where ground level access is not justified.If adequate room and access are maintained for workers, tools, components, and equipment in the design, using auxiliary equipment (such as scaffolding, man lifts, or mobile platforms) to obtain access for maintenance reasons may be permitted.The operator may need to temporarily assume an awkward posture or reach areas not meant for human access in order to identify and inspect the state of C-2 valves, as long as doing so does not result in human error or place the operator in danger of harm or exposure to hazards.
Category‐3 (C-3) Non-operational Valves
Typically, valves are non-operating devices that are employed or examined in specific situations only seldom or infrequently (such as hot tap valves, hydro static test vents, high point vents, or low point drain valves situated in pipe racks), and they are not utilized in activities that are crucial to the HSSE.
Access Requirement for C-3 Valves
Although not necessary, constant access to and visibility of C-3 valves is preferred. No specific location requirements are imposed. Auxiliary equipment like as mobile platforms, human lifts, and/or scaffolding that are used to access C-3 valves must be specified and permitted in the design. C-3 valves should not be accessed with portable ladders. Any suggested exemption or exceptions to this will require careful consideration and approval. Height and reach distances to C-3 valves when operated from auxiliary equipment shall confirm to the “preferred” location.
Notes
Notes
Elixir Engineering conducted a HAZOP Study for Jotun Paints in Oman, addressing risks in design and operation for their manufacturing hub, ensuring safety and efficiency in the MEIA region
Jotun Paints awarded Elixir Engineering the task of conducting a HAZOP (Hazard and Operability) study Oman for Jotun Paints, focusing on their manufacturing hub in Oman. The facility will cater to the Middle East, India, and Africa (MEIA) regions, with an initial production target of 1 million kg in the first year, ramping up to 2.5 million kg by the fourth year. Ensuring a smooth transition from raw material arrangements to the final goods warehouse is part of the meticulous planning.
To meet the increasing demand, engineers designed the plant to handle a capacity of 2.7 million kg across two shifts. The facility includes:
To prevent cross-contamination, dedicated pot mixers and dissolvers, we will use filling machines for both Component A and Component B.
To enhance ergonomics, the plant features:
For increased precision and quality, liquid raw materials will be added straight to the pot mixer via the PLC and Pit scale.Future expansion provisions include an additional floor-mounted dissolver.
After being weighed on a weighing pit scale, raw components such Epoxy Resin 2540, Trimethylolpropane Triacrylate 11452, Aradur 3745# 11441, ROFLEX T70 11453, and Dimethylaminomethyl (Phenol) 11451 are combined with RM powders in a 4-shaft mixer.The finished product is pressed in a hydraulic press and sent to the pail filler unit for subsequent packaging.
The process/utility system and related interfaces are the main emphasis of the HAZOP. The fundamental idea of a HAZOP study is to take a detailed description of the process and question every aspect of it in brainstorming sessions attended by the various experts involved in the process design in order to first identify potential deviations from the intended design and identify potential causes and consequences for those deviations.
The HAZOP investigation moves through the plant node by node.The facilitator defines the node size and route through the plant. Each node is described with:
Primary factors include temperature, pressure, and flow. Additional parameters related to maintenance, safety, corrosion/erosion, instrumentation, and start-up/shutdown are also considered.
Standard guidewords such as No/None, More/Less, As Well As/Part of, Reverse/Other Than, Early/Late, Before/After are applied to each parameter to suggest deviations.
All plausible causes of deviations are considered, focusing on local factors related to the node under study. Unrelated simultaneous events are excluded.
Global impacts are analyzed to determine the ultimate effect of each deviation.
Risk depends on both likelihood and outcome. Safeguards that reduce either probability or consequence are identified, including engineering or administrative measures. Existing and functional safeguards for the operating plant are verified.
Recommendations should be action-based (e.g., Check, Provide, Consider) and assigned to specific work groups. They should clarify what, where, and why actions are needed.
The primary deliverable is a Comprehensive HAZOP Report for the Oman facility.
Elixir Engineering was awarded to perform Fire, Gas Dispersion & Explosion Analysis (FGDEA) and Hazardous Area Classification (HAC) for the wells in the KAUTHER GAS LIFT PROJECT
KGP fields are rich retrograde condensate gas reservoir. As there was a need to extend well life to reduce deferment and improve UR by improving well outflow and reduce OPEX and flaring associated with unloading restoration operations. Gas lift combined with Velocity string VS was determined the best solution for kick-off and for continuous lifting purposes. Accordingly, Rock International intended Elixir Engineering to perform Fire, Gas Dispersion & Explosion Analysis (FGDEA) and Hazardous Area Classification (HAC) for wells in Kauther Gas Lift Project.
Hazardous Area Classification (HAC)
The evaluated separation of a facility into hazardous and non-hazardous regions, as well as the segmentation of the hazardous sections into zones, is known as area classification. A hazardous area is characterised as a three-dimensional place where it is reasonable to assume the presence of a flammable atmosphere at frequencies that necessitate extra care in the design and construction of equipment as well as the management of other potential sources of ignition.
Zone Classification: Hazardous areas are divided into zones based on the likelihood of occurrence and duration of a flammable atmosphere.
Zone 0: That portion of a dangerous location where there is a constant or prolonged presence of combustible air.
Zone 1: The portion of a dangerous location where flammable air is most likely to occur during regular operations.
Zone 2: That part of a hazardous area in which a flammable atmosphere is not likely to occur in normal operation and, if it occurs, will exist only for a short period.
Non-hazardous areas: Areas not covered by any of the aforementioned .
Grade and source of release: A source of release is any location from which a flammable gas, vapour, or liquid may be released into the atmosphere for the purposes of area classification. Based on their expected frequency and duration, three release grades are determined.
Continuous grade release: A release that happens regularly and at brief intervals, or that is almost continual .
Primary grade release: A release that is anticipated to happen in operational procedures that is likely to happen regularly or periodically throughout normal operation.
Secondary grade release: A release that is unlikely to happen during regular operations and, in any case, will only happen occasionally and briefly.
Fluid Categories:
| Fluid | Description |
| A | A combustible liquid that would quickly and significantly evaporate upon discharge. This category includes: a) Any liquefied petroleum gas or lighter flammable liquid. b) Any combustible liquid that, when released, vaporises at a temperature high enough to create more than 40% of its volume without the addition of external heat. |
| B | A combustible liquid that isn't in category A yet is hot enough to boil when released. |
| C | A flammable liquid, not in categories A or B, but which can, on release, be at temperature above its flash point, or form a flammable mist or spray. |
| G(i) | A typical methane-rich natural gas. |
| G(ii) | Refinery hydrogen. |
The Objectives of the FGDEA are to carry out dispersion and thermal radiation assessment to ensure the distance from the wellhead/RMS manifold and the vent heights to the fence is adequate. The following leak sources are considered for the modelling
The FGDEA is a structured and systematic study to identify and assess credible fire and explosion hazards and ensure the facility layout eliminates the potential for escalation as far as reasonably practicable. This involves performing physical effects modelling (PEM) to assess the impact of credible leaks and assess the potential for escalation as per PDO SP-1258 (Quantitative Risk Assessment (QRA) Specification). The study quantifies the physical effects of hydrocarbon releases, as defined by the potential sources of leakage (PSLs) and assesses the potential for impact on personnel due to flammable releases.
The physical effects modelling carried out as part of the FGDEA will be used to optimize the safe distance as per project scope to mitigate escalation and achieve an inherently safe plot, as far as practicable, based on PDO SP-1127.
Steps
Hazardous Area Classification Report compiled with Zone Maps, Documentation of Hazardous Materials, Safety Recommendations. FGDEA Report compiled with Vent Design Recommendations, Contour Maps, Emergency Response Guidelines, Mitigation Measures, and Risk Assessment
Elixir Engineering was awarded to perform Hazard and operability (HAZOP) study for SAHMAH - Hydrocarbon Finder
Hydrocarbon Finder Oman (HCF) was established in 2015 to acquire, explore, develop and produce oil and gas resources in Oman.Hydrocarbon Finder currently has two assets: Block 7 (100%), and Block 15 (90%).
Block 7 Overview:
Infrastructure:
Field Locations:
Recent Developments:
Current Production:
HCF's focus is on significantly increasing oil production in the short, medium, and long term.
Immediate actions include:
Block 15 Overview
Three wells have been drilled in Block 15:
Process Description:
Main Station (SAH-02 Production Facility):
Components included
Inside PDO MOL facility, Pig receiver facility, Flow metering System is located. From the flow metering skid, the measured crude is connected to PDO Main Oil Line.
WH-02 & WH-03
Components Included
Elixir Engineering performed the Hazard & Operability (HAZOP) study for Hydrocarbon Finder.
Hazard & Operability Study (HAZOP)
Hazop for any project or modification serves many purposes including
The HAZOP focuses on the process / utility system and associated interfaces. The basic concept of a HAZOP study is to take full description of the process and question every part of it during brain storming meetings attended by the different specialists involved in the process design to discover firstly what deviations from the intention of design can occur and what their causes and consequences may be.
The main steps involved in a HAZOP study are as follows
Elements of HAZOP study:
Node definition
The HAZOP study progresses through the plant node by node. The selection of the node sizes and the route through the plant is made before the study by the facilitator. The node should be described in terms of: -
Parameters
Flow, Pressure & temperature are usually regarded as the main parameters/elements. Additional parameters relate to general considerations like maintenance, safety, relief, corrosion/ erosion, instrumentation, start-up & shutdown, etc. Some of these may be selected for nodes in a study as appropriate based on relevance and concerns expressed by team members.
Guidewords
Guide words are simple words or phrases used to qualify or quantify the intention and associated parameters in order to suggest deviations. Standard guide words; No/less, more/Less, As Well As/Part of, Reverse/Other Than, Early/Late, Before/After are applicable to each parameter. ‘Other Than’ is a very popular ‘catch all’ guide word at the end of each parameter.
Causes
All credible/ plausible scenarios leading to the deviations, should be considered when determining causes. The Causes should be “Local” to the node being studied. The consequences are deliberated only after listing all the Causes. Two events happening simultaneously without any correlation should not be considered.
Consequence
“Global” effects should be considered for the consequences i.e., keep researching the resulting reactions till you reach the Ultimate Consequence of a deviation.
Safeguards
Risk is a function of both Probability and Consequence. Safeguards reduce either Probability or Consequence. These could be either related to hardware or operator practices & intervention., While selecting safeguards, you may consider engineering or administrative safeguards, but it is necessary to check whether these are existing & functional for the operating plant.
RECOMMENDATIONS
Recommendations should be reported using action-based words (such as Check, Provide, Consider, Ensure, Review etc.), and assigned to specific work groups. It should be verified whether three chief questions have been explained, viz.
Elixir Engineering was awarded to perform Engineering, Procurement, & Construction of Process Facilities Rearrangement at EWT Bejil for Petroweld
COMPANY is established to perform exploration and development of petroleum hydrocarbons in the Kurdistan Region of Iraq with under PSC’s with the Kurdistan Regional Government in Block 11 (Harir-Bejil).“Harir-Bejil Block” is located within the administrative border of Aqra, Soran and Shaqlawa District, approximately 56 kilometers north-east of Erbil and 114km south-east of Duhok/Kurdistan Region of Iraq. The Block covers an area of 1472 km2.
Existing Facility Description:
COMPANY has drilled the Bejil-1 well in Kurdistan and are planning to run an extended well test on the well to determine the size of the oil pool and develop a longer-term production plan for the pool. Sour oil, gas and potentially water are produced from the well through a short pipeline to a new facility is built near the well to separate the emulsion and produce a saleable oil product. The flow from the well Bejil-1 is controlled by a manual choke at the wellhead. The emulsion will flow through an underground pipeline to the facility.
At the Bejil-1 location there is a Manifold Skid SK-900 to allow two future wells to be connected to the same pipeline. This manifold skid includes individual ESD valves that can be closed by the Plant control system. The emulsion flows through a Basket Strainer ST-100A to remove any particulates in the well production fluids.
At the plant inlet, emulsion will first enter a Slug Catcher V-001 where the mixture will be separated into produced gas, produced emulsion and any free water that separates out. Any gas liberated in the slug catcher is directed to the HP flare knock drum (V-170) and then to the HP flare stack (FS-810). Any free water is directed to the produced water storage tank (TK-420). The emulsion from the Slug Catcher V-001 is then directed to the stage 1 heat exchanger (E- 200) where the mixture will be heated.
The emulsion will then flow to the Stage 1 Separator V-100 where any additional vapours are removed. The vapours will be directed to the HP flare KO drum (V-170). A part of the Stage 1 separator (V-100) gas will be routed to the storage tanks for blanketing purposes. The remaining oil and water in the separator then flow through a level control valve to the Stage 2 Heat Exchanger E-210 where the mixture is heated further.
A small of gas is liberated as the mixture is heated. This gas is removed in the Stage 2 Separator V-110, will be directed to LP flare KO drum and then to the LP flare stack (FS-800).
The remaining oil is then pumped (P-110A/B) to a large Demulsification Tank TK-400 where the mixture is allowed to settle. The water will migrate down in the tank and the oil will float up. If the first tank TK-400 is not able to complete the oil/ water separation and produce specification oil, then the oil mixture will be pumped to a second Demulsification Tank TK- 401 for further settling. Any clear water produced in the first tank TK-400 is pumped to the water tank TK-420. Similarly, clear water from tank TK-401 will also be pumped to the water tank TK-420. Clean oil from tank TK-401 will be pumped to the oil storage tank TK-410. If tank TK-400 can successfully separate the oil and water, then the clean oil from this tank will be sent directly to the oil tank TK-410. Tank TK-401 would then act as a backup tank if there are problems with Tank TK-400. The spec oil in TK-410 is then pumped into trucks through the loading stations and hauled away. The produced water is sent to a pond for evaporation.
Sour gas from slug catcher V-001 and Stage 1 separator V-100 is sent to the high-pressure flare knock-out drum V-170 and then to the high-pressure flare stack FS-810.
Sour Gas from Stage 2 separator V-110 is sent to the low-pressure flare knock-out drum V-130 and then to the low-pressure flare stack FS-800. A portion of this gas is sent to the tanks to fill the void in the tanks during the pump-out process. If this gas is not sufficient to maintain the sufficient pressure in the all tanks, extra gas will be sourced from 1st stage separator (V-100).
VRU blowcase (V-840) and Tank Vent blowcase (V-850) are provided along with new GES piping for the liquid fractions accumulation and draining from Gas Equalization System (GES). Gas Equalization system is a system of piping, Blowcases and VRU, designed to equalize the pressure in the gas spaces of De-Emulsification Tanks (TK-400/TK-401), Oil Storage Tank (TK-410) and Water Storage Tank (TK-420) to avoid oil losses from evaporation. VRU Blowcase V-840 is installed on the outgoing gas streams from the tanks TK-400, TK-401, TK- 410 and TK-420. Tank Vent Blowcase V-850 will be installed gas supply lines from V-110, V-100 and V-001. The liquid will be drained from the blowcase vessels by nitrogen under pressure.
The vapours off the tanks TK-400, TK-401, TK-410 and TK-420 are expected to contain high concentrations of H2S. These vapours are gathered and sent to a Vapour Recovery Unit (VRU) which compresses the vapours and sends them to flare.
During truck loading operation, any gas vented from the truck is collected by a Vent Gas Compressor K820 A/B. The compressed sour vent gas is sent to H2S scavenger vessel V820 where the H2S is removed. The resulting sweet gas is then directed to a vent stack VS-830. A Blow case vessel (V-860) is provided at truck loading area to collect the liquids from the loading arms. The collected liquids will be discharged to oil loading line.
Instrument air will be supplied to the plant users by instrument air system (IA-740). It consists of Air compressors, compressor air dryer and compressed air storage vessel. A nitrogen generating system (NG-710) will generate 95% nitrogen stream that will be used for purging when the plant is down and as a backup gas supply to the tanks so loading can take place when the battery is down for whatever reason.
A heat media system FH-710 will be used the heat the emulsion in the Stage 1 and Stage 2 heaters. The heat media will also be used to maintain temperatures on the tanks and some of the process equipment mostly in a battery shutdown situation.Primary and Secondary electric generators will supply power to the whole site.
Diesel is the fuel source for the plant. The electrical generators and the heat media heater are the main users for the fuel. The fuel is stored in a Storage Tank TK-430. The fuel is filtered (F-330) prior to the Pumps P-330 A/B and pumped to the heat media and gravity fed to the generators.The gas from the slug catcher, separators and VRU will flow to a flare knockout drum to remove liquids and then to the flare stack for burning.Drains in the plant will flow to a slop tank. When the tank is full, the pump will start and feed the “slop” to the battery inlet for processing.
Following facilities as per the Project scope are included in this HAZID study.
a) Replacement of the ТК-400/401/410/420 Gas Equalization System:
Gas Equalization System (GES) is a system of piping designed to equalize the pressure in the gas spaces of De-Emulsification Tanks (TK-400/TK-401), Oil Storage Tank (TK-410) and Water Storage Tank (TK-420) during pump-out (inbreathing)/ pump-in (outbreathing) operation to avoid oil losses from evaporation.
The following modification scope for GES system are as follows:
b) Rearrangement of the VST ТК-400/401 Intra-site Piping and Pumping Stations
c) New Roof at Oil Filling-in (Loading) Stations C/D and Roof to close gap between existing roof for Station A/B and new roof for Station C/D
d) New reinforced concrete bund and new Sun-roof for existing TK-430 Diesel Fuel Storage Tank and relocation of existing diesel fuel pumps.
Trace heating of all diesel fuel pipe lines (to main and emergency generators and oil Heat Medium Skid) shall be developed and implemented.
Elixir Engineering done different safety studies for EWT Bejil project.
The safety studies conducted for this project scope is listed below:
Objective
The overall intent of an HAZID study is to assist in demonstrating that the risk associated with all the identified hazards are managed and will be reduced to an acceptable level by:
HAZID is a structured review technique for the early identification of all significant hazards associated with the particular activity under consideration. HAZID is carried out by a systematic analysis of all the threats with the potential to generate health, safety, environmental, asset risks. Once the hazards have been identified, the associated risks are qualitatively assessed and risk prevention and mitigation measures identified in consistency with the adopted Risk Management strategy.
In this workshop, emphasis was on identifying any hazards introduced by activities related to the Project. However, attention was paid to the interactions between the existing facility and their impacts on the project.
HAZID methodology
Many of the hazards and HSE issues are generic for the whole development and are not specific to any part of the plant or location. The procedure is firstly to apply the technique to the whole development as a single entity, as far as possible, and then review discrete areas as appropriate.The study method is a combination of identification, analysis and brainstorming based on the hazards identified with the help of a checklist of potential hazards.
The main topics covered by the checklist are
The HAZID review proceeds as a structured brainstorming of potential hazard scenarios using proper guidewords; the HAZID Checklist is comprehensive but not exhaustive and the use of brainstorming to identify novel or unforeseen hazards may be required.
The HAZID Facilitator will examine the system against the Checklist and within each Checklist section; for each potential hazard that is identified, the specific threat (or cause) and its associated consequences are derived. The adequacy and presence of the existing safeguards (either preventive or mitigating) are assessed and finally, the risk associated to the hazardous event is evaluated with the support of a COMPANY Risk Matrix. Recommendations for reducing risks are identified during the brainstorming, in consistency with the applied risk management process.
Hence, the following review process shall be facilitated
Steps (2) to (6) are repeated until all applicable guide-words have been exhausted and the team is satisfied that all significant deviations have been considered.
HAZID Basic Rules
The following ground rules are set before proceeding with the HAZID Session
Hazard and Operability (HAZOP) Study is a structured and systematic evaluation of a planned and/or existing operation to identify and evaluate potential hazards in design and operation. This study is carried out by a team of engineers from different disciplines.
The team looks at each section of a plant or system or operation (node), considers potential deviations from intended operation and analyses their consequences against any existing safeguards. Impact of identified hazards on safety, asset and environment are assessed.
HAZOP is a guideword driven brainstorming technique. Team members contribute based on their collective experience and lessons learnt from past projects.
HAZOP study records the identified hazards without proposing any solution, unless a solution is obvious.
Proposed solutions may include additional safeguards or operational procedures as necessary.
The study record serves as a guide to determine the Health, Safety and Environment (HSE) issues to be resolved during the project.
Purpose of HAZOP
HAZOP for any project or modification serves many purposes including
Methodology
The HAZOP focuses on the process / utility system and associated interfaces. The basic concept of a HAZOP study is to take full description of the process and question every part of it during brain storming meetings attended by the different specialists involved in the process design to discover firstly what deviations from the intention of design can occur and what their causes and consequences may be.
The main steps involved in a HAZOP study are as follows
Elements of HAZOP Study
Node definition
The HAZOP study progresses through the plant node by node. The selection of the node sizes and the route through the plant is made before the study by the facilitator. The node should be described in terms of: -
Parameters
Flow, Pressure & temperature are usually regarded as the main parameters/elements. Additional parameters relate to general considerations like maintenance, safety, relief, corrosion/ erosion, instrumentation, start-up & shutdown, etc. Some of these may be selected for nodes in a study as appropriate based on relevance and concerns expressed by team members.
Guidewords
Guide words are simple words or phrases used to qualify or quantify the intention and associated parameters in order to suggest deviations.
Standard guide words; No/less, more/Less, As Well As/Part of, Reverse/Other Than, Early/Late, Before/After are applicable to each parameter. ‘Other Than’ is a very popular ‘catch all’ guide word at the end of each parameter
Causes
All credible/ possible scenarios leading to the deviations should be considered when determining causes. The Causes should be “Local” to the node being studied. The consequences are deliberated only after listing all the Causes. Two events happening simultaneously without any correlation should not be considered.
Consequence
“Global” effects should be considered for the consequences i.e., keep researching the resulting reactions till you reach the Ultimate Consequence of a deviation.
Safeguards
Risk is a function of both Probability and Consequence. Safeguards reduce either Probability or Consequence.
These could be either related to hardware or operator practices & intervention., While selecting safeguards, you may consider engineering or administrative safeguards, but it is necessary to check whether these are existing & functional for the operating plant.
Recommendations
Recommendations should be reported using action-based words (such as Check, Provide, Consider, Ensure, Review etc.), and assigned to specific work groups. It should be verified whether three chief questions have been explained, viz.
Objective
The SIL (LOPA) Study is undertaken on safety systems for the purpose of defining a SIL (Safety Integrity Level) rating for Safety Instrumented Functions (SIFs). The SIL rating of a SIF defines the integrity specification (and hence the minimum reliability requirement) and architectural requirements for SIF equipment. The SIL Classification process may be implemented to determine whether the existing or proposed design meets the integrity specification and if not, what changes are necessary to meet the integrity specification.
The following table provides the target performance requirement for each SIL as based on the definition in IEC 61511-1.
| SIL | Low demand mode of operation | Risk Reduction Factor (RRF) |
| 4 | ≥1x10-5 to <1x10-4 | 10,000 to 100,000 |
| 3 | ≥1x10-5 to <1x10-4 | 1,000 to 10,000 |
| 2 | ≥1x10-5 to <1x10-4 | 100 to 1,000 |
| 1 | ≥1x10-5 to <1x10-4 | 10 to 100 |
The following information and steps are required to perform the assessment of a given SIF
Main part of the information described above is based on the HAZOP findings.
Following the steps illustrated in the figure above, the SIF’s required SIL can be determined by means of the next sequence:
| Consequence scale | TMEL |
| C1 Negligible | 10-2 [ev/y] |
| C2 Minor | 10-3 [ev/y] |
| C3 Moderate | 10-4 [ev/y] |
| C4 Major | 10-5 [ev/y] |
| C5 Extreme | 10-6 [ev/y] |
There shall be individual TMEFs for Safety consequence, Environmental consequence, Asset damage consequence and Reputation consequence.
PFD = TMEL / Total MEF
RRF = 1 / PFD
In case of more than one cause or consequence, the highest RRF or SIL requirement shall apply for the respective SIF.
SIL (LOPA) Main Parameters
The following sections show the main parameters to be assigned in each SIF Classification.
Initiating Events Likelihood Estimate
Initiation likelihoods for some typical failures are reported in the following table. Likelihood of more complex/specific initiating causes will be determined during sessions on the basis of the judgement and experience of the Team.
The following parameters can be used as conditional modifiers in LOPA scenarios wherever applicable. It may be noted that, to avoid double accounting, they should not be used as IPL if they are considered as conditional modifiers:
The following rules and values will be used when selecting and assessing the Conditional modifiers to be used for the LOPA.
Independent Protection Layers are divided in the following groups:
All the Protection Layers described above shall be characterised by their relevant Probability of Failure on Demand (PFD) in order to determine the risk reduction potential associated to each of them. The suggested values of Probability of Failure on Demand (PFD) to be used for the identified IPLs are summarised here below:
COMPANY risk matrix will be used to qualitatively assess the consequence, likelihood and risk associated with the identified hazards.It shall be bear in mind that the method adopted will be capable of effectively classifying hazards, but without taking too much time or distracting the team from their primary focus.A five-category system will be used both for consequences likelihood and magnitude classification. In case of multiple consequences for the same deviation, the ‘worst case’ should be selected.
Since the ranking exercise can be very time consuming, it is suggested that, in case of tight schedule due to prolonged discussion, only the worst risk ranking could be recorded among the consequence categories mentioned in the matrix.
Probabilities will be estimated according to the following scale, as per COMPANY's Procedure:
Elixir Engineering was awarded to perform HAZOP Revalidation Study for SR1 (AREA-100, AREA-200, AREA-300, AREA-400, AREA-500 and utilities for SOHAR REFINERY
OQ Sohar Refinery is a major oil and gas processing complex located in Oman. It is one of the largest and most complex refineries in the Middle East, producing a wide range of refined products, including gasoline, diesel, jet fuel, naphtha, LPG, and petrochemical feedstocks.
The OQ Sohar Refinery is located in the industrial area of Sohar, in the northern part of Oman. The refinery was originally built in the 2000s as a joint venture between Oman Oil Company and Aromatics Oman LLC. However, in 2011, Oman Oil Company acquired Aromatics Oman LLC, and the OQ Sohar Refinery became a fully owned subsidiary of Oman Oil Company.
The OQ Sohar Refinery has undergone significant expansions and upgrades in recent years to increase its capacity and improve its efficiency. In 2017, the refinery completed its $3.6 billion Sohar Refinery Improvement Project (SRIP), which involved the construction of a new crude oil unit, a new hydrocracker unit, and upgrades to existing units.
The OQ Sohar Refinery is a critical component of Oman's economy, providing the country with a reliable source of refined products for domestic consumption and for export to other countries in the region. It also supports Oman's growing petrochemical industry, providing feedstocks for the production of plastics, chemicals, and other products
Hazard and Operability (HAZOP) Study is a structured and systematic evaluation of a planned and/or existing operation to identify and evaluate potential hazards in design and operation. This study is carried out by a team of engineers from different disciplines. The team looks at each section of a plant or system or operation (node), considers potential deviations from intended operation and analyses their consequences against any existing safeguards. Impact of identified hazards on safety, asset and environment are assessed.
HAZOP is a guideword driven brainstorming technique. Team members contribute based on their collective experience and lessons learnt from past projects.
HAZOP study records the identified hazards without proposing any solution, unless a solution is obvious. Proposed solutions may include additional safeguards or operational procedures as necessary. The study record serves as a guide to determine the Health, Safety and Environment (HSE) issues to be resolved during the project.
HAZOP for any project or modification serves many purposes including
The HAZOP focuses on the process / utility system and associated interfaces. The basic concept of a HAZOP study is to take full description of the process and question every part of it during brain storming meetings attended by the different specialists involved in the process design to discover firstly what deviations from the intention of design can occur and what their causes and consequences may be.
The main steps involved in a HAZOP study are as follows:
Node definition
The HAZOP study progresses through the plant node by node. The selection of the node sizes and the route through the plant is made before the study by the facilitator. The node should be described in terms of: -
Parameters
Flow, Pressure & temperature are usually regarded as the main parameters/elements. Additional parameters relate to general considerations like maintenance, safety, relief, corrosion/ erosion, instrumentation, start-up & shutdown, etc. Some of these may be selected for nodes in a study as appropriate based on relevance and concerns expressed by team members.
Guidewords
Guide words are simple words or phrases used to qualify or quantify the intention and associated parameters in order to suggest deviations.
Standard guide words; No/less, more/Less, As Well As/Part of, Reverse/Other Than, Early/Late, Before/After are applicable to each parameter. ‘Other Than’ is a very popular ‘catch all’ guide word at the end of each parameter.
All credible/ plausible scenarios leading to the deviations, should be considered when determining causes. The Causes should be “Local” to the node being studied. The consequences are deliberated only after listing all the Causes. Two events happening simultaneously without any correlation should not be considered.
“Global” effects should be considered for the consequences i.e., keep researching the resulting reactions till you reach the Ultimate Consequence of a deviation.
Risk is a function of both Probability and Consequence. Safeguards reduce either Probability or Consequence. These could be either related to hardware or operator practices & intervention., While selecting safeguards, you may consider engineering or administrative safeguards, but it is necessary to check whether these are existing & functional for the operating plant
Risk assessments should be carried out to quantify the risks associated with deviations and their potential consequences, and to assist in determining the adequacy of planned safeguards and the possible need for further action. An initial informal risk assessment should be carried out on each case – Consequence scenario based on the inherent risk in the unprotected state.
The risk matrix included in the below table should be used as a guide. The risk should then be reassessed taking into consideration the planned safeguards and risk reduction measures. For less important risks, the need for further action can be based on the experience and judgement of the HAZOP study team.
Once the reasonable consequence and likelihood of each potential unwanted event is determined, the risk can be ranked using the above “Risk Assessment Matrix” and recorded on the HAZOP study Worksheet.
Recommendations should be reported using action-based words (such as Check, Provide, Consider, Ensure, Review etc.), and assigned to specific work groups. It should be verified whether three chief questions have been explained, viz.
Elixir Engineering was awarded to perform MGP Brownfield Modification for Onshore Depletion Compression OQ Gas network
The Bukha Field is located in Block 8 approximately 23 km offshore from the western coast of the Musandam Peninsula; with the Bukha Alpha platform some 23 km from the Musandam Gas Plant (MGP). Offshore Block 8, which contains the Bukha and West Bukha fields, produced an average of 4,458 barrels of oil equivalent per day during 2018. From January 2019, Block 8 is being operated by the MOGC (Musandam Oil and Gas Company), which is fully owned by MOGC (OQ E&P LLC).
All the production from Block-8 is being processed at onshore processing station i.e. Musandam Gas Plant “MGP”. The inlet arrival operating pressure to MGP is in the range of 15 – 18 barg (220 -260 psig) while downstream gas processing units require an operating pressure of 60 barg (870 psig). Inlet compressors available at the downstream of Slug-catcher (three machines each having a capacity of 20 MMSCFD) is used to boost the pressure from 15 Barg (220 psig) to required 60 barg (870 psig) (with compression ratio ~3.3). The configuration of Compressor shall be maintained in such a way that one compressor should be maintained in standby mode.
Presently, in order to achieve the inlet pressure at MGP (15-18 barg), the wells at Bukha are being operated at 22 barg (320 psig) and west Bukha operating at around 29 barg (420 psig) as shown in the block diagram below.
Production wells are under depletion mode and producing majorly gas and smaller quantity of condensate & water. To enhance the production at the MGP plant inlet, it is proposed to operate MGP plant inlet at reduced pressure of 4.5 barg from 15-18 barg. To facilitate the above proposal, different configuration of inlet gas compressor arrangements was studied part of the conceptual study and option 3A configuration was selected as feasible option. Following modification shall be required to integrate the project scope with existing plant for the reduced operating pressure of 4.5 barg at Slug Catcher A-1001 inlet.
Scope includes the installation of New piping Tie-in shall be made downstream of the particle Filter / Coalescer S-1501A/B for routing the gas to the new LP compressor K-1506A/B (1W+1S) suction via LP suction scrubber V-1506A/B. Gas pressure shall be raised from 3.15 barg at the LP compressor inlet to 17.92 barg to meet the existing Inlet Gas Compressor K-1501A/B/C inlet conditions. Existing inlet gas compressor K-1501A/B/C configuration shall be changed to (1W+2S) to meet the project scope. Gas pressure will be raised by K-1501A/B/C to 60.2 barg as per existing condition to meet the GSU battery limit requirement.
New tie-in shall be made for integrating the new Condensate Booster Pump P-1006A/B downstream of slug catcher A-1001 condensate common line. Condensate operating pressure will be raised from 4.5 barg to the existing operating pressure of 16.2 barg downstream of 10-LCV-001A. P-1006A/B discharge line will tie-in to the upstream of level control valve 10-LCV-001A. Produced water from the slug catcher is re-routed to the existing Skim system instead of connecting to the 10-LCV-001A downstream due to the low operating pressure of slug catcher A-1001.
A new tie-in shall be made to provide fuel gas blanketing for MP production separator with operating pressure of 13 barg (Operating pressure modified from 15.9 barg due to limitation of fuel gas supply pressure of 17.25 barg at E-3701 downstream) & continuous supply to pre-flash vessel to maintain the operating pressure at 12 barg.
Elixir Engineering done different safety studies for MGP Brownfield modification project. The safety studies conducted for this project scope is listed below:
Safety Studies:
Objective :
The intention of the Bow Tie exercise is to develop detailed / comprehensive Bow Tie diagrams which are to be dynamic in nature and can be regularly maintained by asset to reflect live status of each barrier condition. A Bow Tie diagram is a powerful tool for communicating how the control of major accident hazards is achieved.
Methodology :
The Bow Tie analysis will include Bow Tie diagram, for “each MAH scenario” presenting its causes (threats), consequences and potential escalation scenarios, along with the barriers that prevent, control or mitigate the scenarios (either preventive barrier or mitigating barrier). The barriers shall be further analysed for their defeat mechanism (called escalation factors) and corresponding measures provided to overcome the barrier defeat mechanism (called escalation factor controls). The MAH scenario shall encompass both process MAHs and other MAHs applicable to the facility. The process of creating a Bow Tie is most effectively accomplished using a Bow Tie workshop. It is important before the workshop to establish the scope and the context under which the bow ties will be developed.
Overview of BOW TIE :
The general focus of bow tie is managing Major Accident Hazards, as working personnel need to understand how these may occur and the barriers and escalation factor controls deployed to prevent them. Bow Tie diagrams shall be unit level / equipment specific MAH scenarios. A Bow Tie diagram shall be prepared for each MAH scenarios, presenting its causes, consequences and potential escalation scenarios, along with the barriers that prevent, detect, control or mitigate the scenarios (either preventative barrier or mitigating barrier). The barriers will be further analysed for their defeat mechanism (escalation factors) and measures provided to overcome the barrier defeat mechanism (escalation factor controls).
Key elements consider while developing the bow tie:
HAZARD
The ‘hazard’ is an operation, activity, or material with the potential to cause harm. The hazard has the important function of defining the scope for the whole bow tie. Generic hazards can lead to generic bow ties and thus the hazard should be specific. This tends to add value because it increases the level of detail in the rest of the bow tie.
Formulating the Hazard would normally be identified in a PHA (Process Hazard Analysis) process (e.g., HAZID (Hazard Identification Study) or HAZOP (Hazard and Operability Studies))
Top Event
The top event is the moment when control over the hazard or its containment is lost, releasing its harmful potential. While the top event may have occurred, there may still be time for barriers to act to stop or mitigate the consequences. It is possible to identify multiple top events for one hazard – control can be lost over the hazard in different ways. Therefore, one hazard can result in multiple Bow Tie diagrams. For example, the hazard ‘working at height’ can result in two top events ‘dropped object’ and ‘person falls from height’. This will lead to two Bow Tie diagrams with different top events, but the same hazard.
Formulating the Top Event,
Consequence
Consequences are unwanted outcomes that could result from the top event and lead to damage or harm. For each top event there are multiple consequences placed on right side of the diagram, the ‘natural’ approach might be to define threats first. Generally, these would be major accident events, but lesser consequences can be selected if the aim is to map the full range of important safety and environmental barriers.
Formulation of consequence,
Threat
Threats are potential reasons for loss of control of the hazard leading to the top event. For each top event there are normally multiple threats placed on the left side of the diagram, each representing a single scenario that could directly and independently lead to it.
Formulation of Threat
Barrier
Barriers appear on the main pathways (threat to top event or top event to consequence). Barriers must have the capability on their own to prevent or mitigate a Bow Tie sequence and meet all the rule sets/validity requirements for a barrier to be effective, independent, and auditable. Barriers can be physical or non-physical measures to prevent or mitigate unwanted events.
Placement of barriers
| S.No | Item | Acceptance criteria |
| 1. | Preventive Barriers | Minimum of 3 independent, effective and auditable barriers for each identified threat/cause line |
| 2. | Mitigative Barriers | Minimum of 2 independent, effective and auditable barriers for each identified consequence |
| 3. | Escalation Factor Controls (EFC) | Minimum of 2 Escalation Factor Controls (EFC) for each identified Escalation Factor |
Prevention Barrier
A prevention or threat barrier (on the left side of the Bow Tie) is a barrier that prevents the top event from occurring. A key test for a prevention barrier is that it must be capable of completely stopping the top event on its own. This does not mean that it is reliable, only that in principle it can prevent or terminate a threat sequence (for example, an emergency shutdown valve can prevent a top event of ‘loss of containment’, but it can fail if the escalation factor control ‘partial/full stroke testing’ does not occur).There are two main ways in which a prevention barrier can have effect either to prevent the threat from occurring in the first place, or to stop an occurring threat from leading to the top event.
Mitigation Barrier
Mitigation barriers (on the right side of the Bow Tie) are deployed after the top event has occurred and should help to prevent the consequences from occurring or to mitigate the consequences and regain control once it has been lost. There are two main ways in which a mitigation barrier can have effect either to stop the consequence from occurring (ignition prevention), or to reduce the magnitude of the consequence (detection, ESD and emergency response).
A mitigation barrier can have a lower performance than a prevention barrier in that it may only mitigate, not terminate, a consequence. As an example, a fire fighting system may reduce the impact of the fire but not eliminate it. Similarly, an ignition control barrier only reduces the likelihood of ignition but does not eliminate this potential.
Escalation Factor And Escalation Factor Control
An escalation factor can apply to barriers on either side of the Bow Tie diagram. For clarity of visual appearance, often they flow from the left on the prevention side, and from the right on the consequence side, but they are the same in all other respects. Controls along the escalation factor pathway are called escalation factor controls. The escalation factor is a condition that can reduce the effectiveness of the barrier to which it is attached. An escalation factor does not directly cause a top event or consequence, but since it degrades the main pathway barrier, the likelihood of reaching undesired consequences will be higher
Hazard and Operability (HAZOP) Study is a structured and systematic evaluation of a planned and/or existing operation to identify and evaluate potential hazards in design and operation. This study is carried out by a team of engineers from different disciplines.
The team looks at each section of a plant or system or operation (node), considers potential deviations from intended operation and analyses their consequences against any existing safeguards. Impact of identified hazards on safety, asset and environment are assessed.
HAZOP is a guideword driven brainstorming technique. Team members contribute based on their collective experience and lessons learnt from past projects. HAZOP study records the identified hazards without proposing any solution, unless a solution is obvious.Proposed solutions may include additional safeguards or operational procedures as necessary. The study record serves as a guide to determine the Health, Safety and Environment (HSE) issues to be resolved during the project.
Purpose of HAZOP:
HAZOP for any project or modification serves many purposes including
Methodology:
The HAZOP focuses on the process / utility system and associated interfaces. The basic concept of a HAZOP study is to take full description of the process and question every part of it during brain storming meetings attended by the different specialists involved in the process design to discover firstly what deviations from the intention of design can occur and what their causes and consequences may be.
The main steps involved in a HAZOP study are as follows:
Elements of HAZOP Study:
Node definition
The HAZOP study progresses through the plant node by node. The selection of the node sizes and the route through the plant is made before the study by the facilitator. The node should be described in terms of: -
Parameters
Flow, Pressure & temperature are usually regarded as the main parameters/elements. Additional parameters relate to general considerations like maintenance, safety, relief, corrosion/ erosion, instrumentation, start-up & shutdown, etc. Some of these may be selected for nodes in a study as appropriate based on relevance and concerns expressed by team members.
Guidewords
Guide words are simple words or phrases used to qualify or quantify the intention and associated parameters in order to suggest deviations.
Standard guide words; No/less, more/Less, As Well As/Part of, Reverse/Other Than, Early/Late, Before/After are applicable to each parameter. ‘Other Than’ is a very popular ‘catch all’ guide word at the end of each parameter
Causes
All credible/ possible scenarios leading to the deviations should be considered when determining causes. The Causes should be “Local” to the node being studied. The consequences are deliberated only after listing all the Causes. Two events happening simultaneously without any correlation should not be considered.
Consequence
“Global” effects should be considered for the consequences i.e., keep researching the resulting reactions till you reach the Ultimate Consequence of a deviation.
Safeguards
Risk is a function of both Probability and Consequence. Safeguards reduce either Probability or Consequence.
These could be either related to hardware or operator practices & intervention., While selecting safeguards, you may consider engineering or administrative safeguards, but it is necessary to check whether these are existing & functional for the operating plant.
Objective:
The purpose of the document is to identify hazardous conditions or high-risk situations and to evaluate concurrent activities along with production operations. SIMOPS are developed where work parties under different management structures carry out work, which results in hazards that may impact the other. e.g. construction and/or drilling in the same area.
Methodology:
SIMOPS matrices are constructed by group of technical personnel such as engineers of various discipline, and they are typically rooted in existing safety documents such as regulator-required HSE cases, HAZID report, HAZOP report safety “bow-tie” charts, procedural documents, and relevant safety standards.
The following aspects are analysed and recorded in the SIMOPS workshop:
The workshop team ranked each identified hazard according to the potential consequence and likelihood of occurrence with existing safeguards in place, HSE Risk Assessment Matrix. The likelihood and consequences of a hazard were mutually agreed (team consensus). Where information on complex hazards was not readily available, brainstorming, and open discussion were facilitated to ensure a collective/ common understanding of these hazards. The study team made recommendations for risk reduction where appropriate.
Essentially, the SIMOPS process flow chart is given below and further explained as follows:
RISK RANKING
The SIMOPS study applies a risk ranking matrix for assessing the risks associated to the activities in the SIMOPS MOPO. The risk ranking has been carried out in a qualitative manner based on the team experience of the consequence and the likelihood to each hazard scenario. Using a OQ HSE risk ranking matrix attached in Fig.1.6 OQ HSE Risk Matrix, each hazard is given a risk ranking with respect to impact on People, Asset, Environment and Reputation.
Procedures:
Constructability Review is systematic and structured multi-discipline workshop that is performed at EPC Stage of project lifecycle, to ensure that the facility is constructed safely and on time. The review shall assess "the ability to construct” from a construction (not design) viewpoint.
Constructability Review includes all aspects of construction work preparation, execution and completion that can make project safer and more cost effective to build, while maintaining quality, safety and access for personnel, tools and equipment during construction, and post- construction phase.
The main objectives of Constructability review are:
Methodology:
The constructability review was undertaken using following steps:
Major Challenges, Difficulties, Issues And Concerns
For each of the criteria defined in the constructability worksheet, any major challenges, difficulties, issues or concerns identified that could have an impact on Constructability and the Project achieving its Objectives will be initially discussed by Review Team members in the Workshop.
Following discussion and agreement by the Review Team, any recommendations / actions identified based on each criterion subject to analysis were recorded in the Constructability Worksheet including action parties responsible for action closure.
Recommended Action To Be Considered
If there were no current resources or no data / knowledge available about the specified criteria used in the analysis, a recommendation will be made based on Team consensus to address the concerns / issues relating to the criteria specified. In addition, where the Review Team thought appropriate, additional criteria was added to the Constructability Check List specific to this Project and included in the analysis.
General:
Valves are rated by criticality to help ensure that critical valves are located to provide for rapid and effective identification and operation. The following three categories are recommended. Risks to health and safety, including risk of human error, shall be kept ALARP.
Category-1 (C-1) Critical Valves
Valves include those essential to normal or emergency operations where rapid and unencumbered access is essential. The height, reach distances and visibility shall conform to the “preferred” location as outlined in the following sections.
These are valves that meet any or all of the following criteria:
Access Requirement for C-1 Valves
Permanent accessibility shall be provided via a permanent standing elevated surface. If such access at ground or deck level is not practical, access by stairs to the elevated platform is acceptable.Valve identification and status shall be clearly visible to an approachable operator position i.e., on an adjacent walkway, access platform, or in space around equipment that is intended for human access.
Category-2 (C-2) Non-Critical Valves
Valves are those that are not critical for normal or emergency operations but are used during routine inspection or maintenance activities.
These are valves that meet any or all of the following criteria:
Access Requirement for C-2 Valves
Height & reach distance and visibility of C-2 valves should be the same as for C-1 valves i.e., “preferred” location as outlined in the below figures. C-2 valves may be located within the “acceptable area” as outlined in the below Figure, depending on their size and the force needed to operate them. Where ground level access is not justifiable, a vertical fixed ladder plus a small standing surface shall be provided for access to C-2 valves.
The use of auxiliary equipment to gain access (e.g., mobile platforms, man lift, or scaffolding) for maintenance purposes may be acceptable as long as it is indicated and allowed for in the design by preserving sufficient space and access for personnel, tools, parts, and equipment.
Identifying and inspecting the status of C-2 valves may require the operator to enter space not intended for human access, or to temporarily adopt an awkward posture provided doing so does not induce human error or put the operator at risk of injury or exposure to hazards.
Category-3 (C-3) Non-operational Valves
Valves are normally non-operating valves that are used or inspected in particular circumstances on an infrequent or rare basis (e.g., hot tap valves, hydrostatic test vent, high point vent or low point drain valves located in pipe rack) and are not used in HSSE critical activities.
Access Requirement for C-3 Valves
Permanent accessibility to and visibility of C-3 valves is desirable but not essential. No specific location requirements are imposed.The use of auxiliary equipment to gain access (e.g., mobile platforms, personnel lift, and/or scaffolding) to C-3 valves shall be indicated and allowed for in the design.Portable ladders should not be used for accessing C-3 valves. Any proposed exception(s) to this shall be subject to specific review and approval.Height and reach distances to C-3 valves when operated from auxiliary equipment shall conform to the “preferred” location as outlined in the below figures.
Notes
Notes:
