HAZOP study for EPIC -Sewage Operating Systems, LR1 & LR2 (Refinery) FEED line , Barzan Onshore Asset, & LNG Flash gas exchanger facilities of Qatar Gas

Qatar Gas facility -HAZOP study

iFluids Engineering and Consultancy WLL was awarded to perform HAZOP studies for EPIC various facilities of Qatar Gas, including:

  • HAZOP study for the upgrade of Sewage Operating Systems in DOPET
  • HAZOP study for installing filters in LR1 AND LR2 (Refinery) condensate line in Medgulf Construction Company W.L.L
  • Baseline HAZOP for Barzan Onshore Asset for Qatar gas Operating Company Ltd
  • HAZOP Study EPC services for isolation for Flash gas exchanger.

What is HAZOP Study?

A Hazard and Operability (HAZOP) Study is a methodical and organized assessment of an ongoing or planned operation. Its main purpose is to detect and assess possible risks throughout the design and operational phases of a process. To know more on HAZOP Study Click Here

Case Study 1 -HAZOP study for the upgrade of sewage operating systems in DOPET

Qatar Gas (QG) relies on the infrastructure of Ras Laffan Industrial City (RLIC) for its LNG production and shipping operations. In the mid-1990s, QG1 Utilities established an effluent collection facility to manage wastewater from operational personnel and facilities. However, since 2005, the expansion of LNG facilities has led to a significant increase in QG OPCO support staff in non-plant, off-site areas. This surge in personnel has strained the capacity of the wastewater gathering and treatment systems, creating operational challenges.

Effluents generated from various sources, including LR, CLNG, RLTO, and others, are transported to RLIC’s treatment plant. To address these capacity issues, a comprehensive study was undertaken to assess all fluid streams, both current and anticipated. This evaluation identified deficiencies in the existing collection and treatment systems, prompting the initiation of Engineering, Procurement, and Construction (EPC) activities following the Front-End Engineering Design (FEED) phase.

The Hazard and Operability (HAZOP) Studies played a pivotal role in this endeavor, aiming to detect and evaluate potential hazards within planned and existing operations, spanning the design and operational phases. A multidisciplinary team of engineers conducted these investigations, meticulously examining each node within the plant, system, or activity. Their objective was to scrutinize potential deviations from intended operations and assess the consequences in light of existing safety measures. This evaluation extended to considerations of safety, asset integrity, and environmental impacts associated with identified hazards.

The HAZOP process adopted the Guideword Method, aligned with HAZOP Methodology, to comprehensively identify potential hazards. The team systematically identified credible causes and their associated consequences. To prioritize these hazards, the HAZOP Team utilized the QG Risk Assessment Matrix ranking them based on both frequency and severity. The risk rating considered severity in the absence of precautions and the likelihood when precautions were in place.

Guidewords played a pivotal role in guiding the HAZOP investigation, facilitating brainstorming sessions among team members. Each team member brought their wealth of experience and insights from past projects to the table.

It’s noteworthy that the HAZOP investigation primarily serves to identify hazards rather than prescribing specific solutions, unless solutions are immediately evident. Based on the findings, the study may recommend additional safety measures or operational protocols. The comprehensive record generated by the HAZOP study serves as an invaluable reference tool for addressing Health, Safety, and Environment (HSE) concerns throughout the project’s lifecycle.

In summary, the QG wastewater management project at RLIC faced challenges due to staff expansion and increased effluent generation. The HAZOP Studies, conducted by a multidisciplinary team, played a crucial role in identifying potential hazards and assessing their impact on Safety, Asset integrity, and the Environment. This systematic approach informed the project’s design and operational improvements, ensuring the mitigation of identified risks.

The primary objectives of the HAZOP study encompass:

  1. Recognizing and assessing risks and hazards associated with process facilities.
  2. Identifying operational and maintenance issues.
  3. Evaluating the potential consequences of these hazards.
  4. Assessing the effectiveness of existing safeguards and risk reduction measures, both in design and procedures.
  5. Providing recommendations for supplementary safety measures or modifications to current operating procedures to enhance facility preparedness for identified risks.

The essential documents required for the HAZOP study include:

  • Project and Facility Description
  • Facility Layout Drawings
  • Piping & Instrumentation Diagrams
  • Cause-and-Effect Matrix
  • Company Policies, Operating Procedures, and HSE/Safety Philosophy
  • Incident Reports

During HAZOP sessions, the study team systematically analyzes the process under review, employing a set of guidewords to structure their evaluation. Team members represent diverse fields of expertise, ensuring a comprehensive assessment.

The HAZOP study team comprises experts from Qatar Gas, DOPET, Worley, and iFluids Engineering & Consultancy W.L.L., representing various disciplines such as Process, Piping, Instrumentation & Control, Equipment Maintenance, Catering Services, Electrical, HSE, Civil and Structural, System & Control, Project, Operations, Mechanical, and Maintenance. This multidisciplinary approach ensures a comprehensive evaluation of hazards and risks in the operation.

Case Study 2 – HAZOP Study for EPIC filters in LR1 AND LR2 (Refinery) FEED condensate line

The project under consideration involves the installation of a filtration facility in Laffan Refineries LR1 & LR2 to address recurring issues with feed condensate heater tubes clogging. This project aims to improve operational reliability, reduce financial losses, and minimize environmental impacts resulting from heater choking incidents. To ensure the safety and effectiveness of this modification, a Hazard and Operability (HAZOP) Study was conducted.

During the HAZOP session, the team examined the LR1 & LR2 feed condensate system, considering deviations from the intended operation and their potential consequences. They also assessed the existing safeguards in place. The objective was to comprehensively understand hazards, assess the adequacy of risk reduction measures, and recommend additional safeguards or operational procedures if necessary.

The HAZOP study team included experts from various disciplines, including Process, Piping, Instrumentation & Control, Electrical, HSE, Civil and Structural, System & Control, Project, Operations, and Maintenance. This diverse team brought their individual experiences and expertise to the table, enhancing the overall assessment.

The HAZOP study is a critical reference tool throughout the project, helping identify and address Health, Safety, and Environment (HSE) concerns. It ensures that potential hazards and risks associated with the facility are properly understood and mitigated. The study does not prescribe specific solutions but highlights areas where additional measures may be needed to enhance safety and reliability.

In summary, the HAZOP Study for the LR1 & LR2 feed condensate filtration facility project is a comprehensive evaluation undertaken by a multidisciplinary team. Its primary goals are to identify and assess potential hazards, evaluate existing safeguards, and recommend improvements to enhance the safety and reliability of the facility. This systematic approach ensures that the project addresses health, safety, environmental, and reputational concerns while optimizing operational performance.

Case study 3 – Baseline HAZOP for Barzan Onshore Asset for Qatar gas Operating Company Ltd

The primary aim is to assess potential hazards and their impacts on health, safety, environment, and the company’s reputation. The focus is on ensuring adequate protective measures are in place or will be implemented to manage these hazards, especially considering changes since the detailed engineering HAZOP review.

The Barzan Onshore facility, situated at Ras Laffan Industrial City, produces treated sales gas, ethane, LPG, untreated field condensate, plant condensate, and liquid sulfur. The facility, consisting of two identical trains, has a combined inlet capacity of 1.9 BSCFD Full Well Stream (FWS) on a dry basis. It also includes utilities facilities, off-plot facilities, and pipelines, with the two trains designed to handle a combined capacity of 1.9 BSCFD for various composition cases.

The study involved a well-equipped team, including personnel from Qatar Gas in loss prevention engineering, operations, process, control systems, and maintenance, along with iFluids Engineering facilitators and scribes.

The HAZOP study focused on the identification and analysis of potential hazards using the Guideword Method within the established HAZOP Methodology. The causes and consequences of identified hazards were scrutinized, and risks were ranked as high, medium, or low based on frequency of occurrence and severity. Risk severity was assessed without considering existing safeguards, while likelihood was determined considering the safeguards in place.

The study addressed a multitude of operational aspects, including the treatment of sour gas, NGL recovery, molecular sieve polishing units, Selexol Mercaptan Removal Unit, and sulfur recovery. The process involved in-depth analysis of equipment and operational scenarios, considering various compositions and environmental conditions.

The HAZOP study adhered to specific assumptions and limitations, focusing on steady-state operation and neglecting quantitative analysis, design review, project scope, schedule, or commercial issues. Assumptions related to single-point failures, safeguard independence, and specific equipment conditions were considered during the analysis.

The team generated recommendations based on the findings, prioritizing the removal of causes over mitigating consequences and ensuring technical soundness. Suggestions were made with the goal of resolving identified hazards, and the team aimed to achieve consensus on each recommendation.

Responsibility for implementing and closing out action items arising from the HAZOP falls on the Asset Loss Prevention focal point for baseline HAZOPs and on the Project Manager for projects. Close-out sheets document the responses, final actions, and justifications, providing a transparent record of decisions and solutions.

In summary, the HAZOP study for Barzan Onshore is a comprehensive risk assessment ensuring the facility’s continued safe and efficient operation, aligning with industry standards and best practices.

Case study 4 – HAZOP Study EPC services for isolation for Flash gas exchanger.

The objective of the Engineering, Procurement, and Construction (EPC) services pertains to two combined shutdown projects specifically focusing on the isolation of LNG Flash Gas Exchangers, which are of the Brazed Aluminum Heat Exchanger type (BAHX). These exchangers are susceptible to thermal stresses from temperature fluctuations, posing a risk of potential failure and subsequent losses in LNG production.

To mitigate this, the study explores feasible options for online replacement or maintenance during LNG train operation. The proposed solution involves the installation of a bypass line (34 inches) with an isolation valve or Double Block and Bleed (DBB) valves for the Flash Gas Exchanger. Additionally, a tie-in with a 42-inch FRP interconnection line is suggested, incorporating 56-inch and 38-inch DBB isolation valves for inlet and outlet.

Concurrently, a Hazard and Operability (HAZOP) Study, a systematic assessment conducted by a team of engineers with diverse expertise, is implemented to identify and evaluate potential hazards during both design and operation phases.

Using guidewords, the team employs a brainstorming technique to assess individual segments or nodes of the plant, system, or operation. The study analyzes the likelihood and consequences of deviations from intended operation, considering existing safeguards. The HAZOP methodology refrains from suggesting solutions but documents identified hazards, leaving room for potential resolutions such as supplementary measures or functional protocols. The study record serves as a vital tool for addressing Health, Safety, and Environment (HSE) concerns throughout the project, ensuring a comprehensive approach to risk management and operational safety.

HAZOP Methodology

The objectives of the HAZOP study are:

  • The task at hand is locating and evaluating potential risks and hazards that could be connected to processing facilities.
  • Identify operational and upkeep problems.
  • Recognize these dangers/challenges and evaluate the likely results.
  • If further procedures or processes are considered necessary, propose them.

These actions will result in a facility that is better designed and operated to reduce the identified potential dangers.

  • Following are the documents required:
  • Project and Facility Description
  • Facility Layout Drawings
  • Process Flow Diagrams
  • Piping & Instrumentation Diagrams
  • Cause & Effect Matrix
  • Hazardous Area Classification Drawings

The guidelines, operational methods, and company’s Health, Safety, and Environmental (HSE) philosophy are all covered in the paper.

  • Incident reports
  • Facility Risk Register

Each node of the plant is methodically examined as part of the HAZOP examination. Prior to the study, the facilitator chooses the node sizes and the path through the plant. It is necessary to explain the node in terms of:

  • Brief description of the node
  • Typical operating and design conditions

Guidewords are straightforward terms or expressions that are used to define or assess the purpose and associated parameters with the intention of suggesting deviations.

  • No, Reverse/Misdirected, Less/More, Low/Less, More/High, and Less/More.

The following are examples of typical HAZOP parameters or components.

  • Flow, Pressure, Temperature, Level, Viscosity
  • Composition, Contamination
  • Operation, Start-up, Shutdown, Maintenance, Isolation
  • Sampling
  • Corrosion
  •  Operability & Maintenance Issues Safety
  • Instrumentation & Control

When the process design intent is not adhered to, this is referred to as a deviation.  All deviations (no flow, higher temperature, etc.) are discovered by sequencing the metrics and guidelines. It is possible that the deviations under examination have a notable amount of overlap, such as the possibility that the lack of flow could have an effect similar to an increase in pressure.

To determine all potential causes of the observed divergence, the team will engage in a collaborative ideation process. It is important to consider all possible causes because they could have different effects and require different responses. Always local or limited to the node, causes are. It has been condensed and kept to the node under discussion, if at all possible.

Three main categories of causes exist, arranged in decreasing order of likelihood:

  • Human error
  • Equipment failure
  • External events

It should be observed that the word “cause” includes one tag clearly in the worksheet. This suggests or contains additional appropriate tags for connected equipment.

The potential consequences for each cause are discussed and assessed within the limits of the information available and the expertise of the team. There may be several consequences involving escalation to other pieces of equipment. All significant effects of the cause, anywhere in the institution, are listed. Worst-case consequences are described assuming that no safeguards are in place or working.  “Safeguards” are controls that stop the cause from happening, warn the Operator when deviations occur, and/or lessen the effects if the cause does happen. For instance, they include:

  • Those systems, engineered designs, and written procedures that are intended to prevent a catastrophic release of hazardous or flammable material;
  • Those systems that are specifically engineered to identify and provide timely notification following the onset of a hazardous or combustible substance discharge; and
  • The aforementioned refers to the set of protocols or documented measures that serve to lessen the impact of a hazardous or flammable substance discharge.

Furthermore, it should be mentioned that the positive isolation approach is used when managing any facility for maintenance tasks like control valve repair, which necessitates flange breaking, etc. The team then assesses the listed Safeguards based on their sufficiency to remove or maintain the potential risks within acceptable bounds after the major safeguards have been specified.

The study team used a methodical brainstorming process to assess the procedure that would be discussed in the planned meeting at the HAZOP session.

This was accomplished through the use of a set of Guidewords, which were employed to structure the review. The study team is composed of individuals representing a variety of departments/specialties.

The HAZOP workshop adopts the subsequent procedure:

  • Selecting a Node (i.e. vessel or line) to be assessed;
  • Process Engineer or an Operation Representative describing the Node’s function and layout;
  • Identifying a potential Deviation that may occur within that Node using a Guideword and Parameter;
  • Determining and assessing the causes of design intent deviations;
  • Assessing the potential effects of the mentioned deviations without taking into account any existing safeguards;
  • Identifying any Safeguards in place in order to prevent the failure scenario from occurring or mitigate the Consequences if it occurs;
  • Where necessary, suggestions are made to further reduce the consequences.