Hazard Identification (HAZID) & Mitigation Strategies for Amjad & MMW Hookup Project, Oman

Project Summary

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.

The Major Scope of this Project is Briefly Described Below:

Amjad Field

• One MSV with slots for oil producing wells at Amjad field.
• Gross fluid, CS+PE/Roto, 300# A/G pipeline from proposed MSV located in Amjad field & MSV located in MMW field Oman to tie-in location proposed on existing manifold located in Marmul Alpha Gathering Station.
• Piping Spool for Coriolis meter and Water Cut meter.
• Provision for Mobile Well Testing Unit (MWTU).
• One Relief/ Maintenance Pit with a level transmitter.
• 1 no of Full Flow relief valve on the MSV test header.
• CS+ Roto lined A /G dilution water supply manifold with slots.
• Engineering scope of CS, 300#, A/G dilution water distribution pipeline and the dilution water hook-up at the respective oil producer wellheads with electromagnetic flowmeter and associated valves for individual oil producer wells. The execution of the dilution water pipeline system will be done by OSE2 team.
• DG set is used for power supply at the wellheads in absence of OHL.

MMW Field

• One MSV with slots for oil producing wells at MWW (Marmul West) field Oman.
• Piping Spool for Coriolis meter and Water Cut meter.
• Provision for Mobile Well Testing Unit (MWTU).
• Full Flow relief valves + 1 Installed spare at Marmul West.
• Full Flow relief valve on MSV test header.
• One Relief/ Maintenance pit with a level transmitter.
• CS+ Roto lined A /G dilution water supply manifold with slots.
• Engineering scope CS,  300#, A/G dilution water distribution pipeline and the dilution water hook-up at the respective oil producer wellheads with electromagnetic flowmeter and associated valves for individual oil producer wells. The execution of the dilution water pipeline system will be done by OSE2 team.
• DG set is used for power supply at the wellheads in absence of OHL.

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.

Safety Studies

• HAC Schedule
• HAC Layout
• Escape Route Layout
• FGDEA (Fire, Gas Dispersion & Explosion Analysis)
• Safety Sign Layout

Hazardous Area Classification (HAC)

What is Hazardous Area Classification (HAC) - 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

Fire & Gas Dispersion Explosion Assessment (FGDEA)

• 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.

The Objectives of this Study

• Determine all plausible hydrocarbon hazardous events (e.g., jet fire, flash fire, pool fire, flammable gas dispersion, and explosion);
• Evaluate the effects of the final results resulting from releases;
• Evaluate the toxic impacts in accordance with the requirements in SP-1190;
• Evaluate the potential impact on adjacent units as well as buildings (if included in the project scope), taking into account the location of the potential releases;
• Give a warning about the possibility of an explosion and fire escalation.
• Determine protection / mitigation measures to prevent escalation as appropriate for the phase of development).

The Overall Study Approach is Summarised as Follows

• Develop assumptions;
• Establish the assessment criteria;
• Determine plausible hazardous risk scenarios and possible sources of leaks;
• Launch the software, then determine the impact radius for flammable dispersion and unintentional ignition;
• Report the outcomes for flammable dispersion and unintentional ignition.
• Analyze the results against assessment criteria;
• Provide the findings for every leak source together with the corresponding plausible scenarios;
• Analyze the results against assessment criteria;
• Conclude if the identified impact is acceptable and if the case recommend additional mitigation's.

Hazard Identification