HAZOP Study – EPIC for DR Plant, NG Supply System Facilities, Subsea pipelines, Compressor Houses, Onshore Gas Plant, & Catalyst Mix Tanks.

HAZOP study for EPIC facilities

iFluids Engineering and Consultancy WLL was awarded to perform HAZOP study for the following projects:

  • HAZOP Study for Entire DR Plant, NG Supply System and EF-5 Plant of Qatar Steel.
  • HAZOP study For Engineering Disciplines For Rerouting Of EGC’s Seal Gas, Settle-Out Gas And HP Fuel Gas
  • HAZOP Study for Automatic Fire Detection & Mitigation System For Compressor Houses QAFCO 1, 2, 3 & 4 Plant
  • HAZOP study for subsea pipelines to the Onshore Gas Treatment Plant (OGTP) in RLIC
  • HAZOP Study for Construction of New Polished Water, NAO Utility and Catalyst Mix Tanks.

What is HAZOP Study?

A Hazard and Operability (HAZOP) Study is a systematic and structured evaluation conducted on an existing or proposed operation. Its main goal is to methodically identify and evaluate potential hazards at various stages of a process, ranging from the initial design phase to the actual operational stage. To know more Click Here

Case Study 1 – HAZOP Study for Entire DR Plant, NG Supply System and EF-5 Plant of Qatar Steel.

Qatar Steel operates a Natural Gas (NG) receiving and supply station, vital for powering various plants within the company, including Direct Reduction, Rolling Mill, Electric Furnace & Continuous Casting, and Lime Calcination Plant. Qatar Petroleum supplies the NG to Qatar Steel’s station, where it undergoes pressure regulation to distribute it throughout the company. This station plays a crucial role in maintaining a stable NG pressure for Qatar Steel consumers.

The NG arriving via the pipeline is initially filtered to remove dust particles. It then goes through a pressure control valve and is distributed to consumers, with flow rates measured by an orifice flow meter at the Direct Reduction Plant and Steel Plant line. An emergency shutdown system is in place to automatically activate shutdown valves in case of issues with the main line’s pressure-reducing equipment, abnormal secondary pressure increases, or gas flow anomalies.

The NG receiving station is designed to ensure a consistent NG supply to Qatar Steel’s operations while filtering out impurities. The emergency shutdown system enhances safety by isolating the gas flow when necessary. NG remains the primary energy source for heating purposes across various Qatar Steel plants, highlighting the station’s critical role in the company’s operations and ensuring a reliable energy source.

Case Study 2 – HAZOP study for subsea pipelines to the Onshore Gas Treatment Plant (OGTP) in RLIC.

Dolphin Energy Limited (Dolphin) is responsible for producing and supplying large quantities of Natural gas from the offshore North Field of Qatar, which is sent by subsea pipelines to the Onshore Gas Treatment Plant (OGTP) in Ras Laffan Industrial City (RLIC) for gas treatment and delivery to the United Arab Emirates (UAE).

The primary purpose of conducting a HAZOP (Hazard & Operability) study is to assist in the effective management of project risk by promptly identifying potential hazards and operability issues. This study aims to minimize the likelihood and severity of incidents that could adversely affect personnel, facilities, assets, and the environment. Additionally, it seeks to improve safety and reliability in the design process.

The HAZOP study shall be conducted in accordance with the methodology outlined in Dolphin Energy’s PHA Protocol, Dolphin Energy’s HSE Risk Management Procedure, HSES Risk Assessment Procedure & Process Hazard Analysis (PHA) Guideline. The study will be based on the above-mentioned scope of work.

Case Study 3 – HAZOP Study for Automatic Fire Detection & Mitigation System For Compressor Houses QAFCO 1, 2, 3 & 4 Plant

Qatar Fertilizer Company has undertaken this project for Design, Engineering, Material Supply / Installation Performance / Testing & Commissioning of Automatic Fire Detection & Mitigation System for Compressor Houses QAFCO 1, 2, 3 & 4 Plant.

Qatar Fertilizer Company at its QAFCO 1-4 site, has four Compressor houses each having Natural Gas/ Process Air/ Synthesis Gas and Ammonia Compressors for Ammonia plants/ CO2 Compressor for Urea plants and Instrument Air / Working Air Compressors along with lube oil systems. Presently these compressors and their lube oil systems are not having the automatic fire detection and mitigation system. Qatar Fertilizer Company intends to install Automatic Fire detection system & Water Deluge Mitigation System for Natural Gas Compressor, Synthesis Gas Compressor and associated Lube Oil Systems in these compressor houses. Contractor is fully responsible to carry out all required project management, design, engineering, material supply, installation, performance testing and commissioning for this Contract.

The objective of this project is to supply fire water to the segments of Compressor house 1, 2, 3 and 4 from the existing fire water main supply line. Identifying and assessing potential hazards in design and operation is the goal of a Hazard and Operability (HAZOP) Study, which is an organized and methodical analysis of a planned and/or existing operation. A group of knowledgeable individuals from several areas is working on this topic. The team assesses potential deviations from intended operation, studies their effects, and compares them to any existing safeguards as it examines each section of a plant, system, or activity (node). The effects of the identified risks on property, safety, and the environment

Case Study 4 – HAZOP study For Engineering Disciplines For Rerouting Of EGC’s Seal Gas, Settle-Out Gas And HP Fuel Gas

The Dolphin onshore plant is divided in two parallel and identical streams. Each stream can be operated independently. As per original design, the unit requires following gas venting to flare header sometimes during normal operation:

  • Primary seal gas venting from standby EGCs
  • Settle-out gas venting after EGCs stop/trip
  • HP fuel gas venting during warm-up of GT fuel gas line before EGC start

As part of annual flaring reduction plan, implement the modifications as described in this document to prevent venting of all the above gases to flare headers. Proposed modifications will allow these gases to be recovered and re-routed to 48” EGC common suction header wherein these gases will get mixed with sales gas and exported.

The goal of the HAZOP (Hazard and Operability) study is to help manage project risk by finding hazards and operability problems early on. It also aims to reduce the likelihood and effects of an accident that could hurt people, the plant, property, and the environment, as well as improve the safety and reliability of the facility’s design.

Case Study 5 – HAZOP Study for Construction of New Polished Water, NAO Utility and Catalyst Mix Tanks.

This case study presents the proceedings of the HAZOP study carried out for Construction of New Polished Water, NAO Utility and Catalyst Mix Tanks.

The project scope is to:

  • Build new Catalyst mix tank including Catalyst Mix Tank mixer, new Catalyst recirculation pump and new Catalyst Recirculation heater. The existing Catalyst mix tanks are carbon steel and designed to hold working capacity of 821 m3. QChem intends to build a new spare tank of similar capacity to enable the bottom plate replacement of existing Catalyst mix tanks. New Catalyst mix tank will be spare tank for the two existing Catalyst mix tanks. Existing loading / unloading pumps will be used.
  • Build a new common NAO Utility Tank spare to NAO Wash Water Tank, Fresh Solvent Tank, Spent Solvent Tank and Spent Caustic Tank to execute any maintenance works. New NAO Utility Tank will be a spare for above four existing Tanks. This new tank capacity will be provided with PWHT. As part of the project scope, a new tank heater, a new side entry tank mixer, and two NAO Wash Water Treatment Feed Pump are provided as the existing NAO Wash Water pumps are not adequate to take suction from new utility Tank.
  • Build a new Polished Water Tank sparing to the existing Polished Water Tank and provide a new Polished Water Pump to ensure that there will be uninterrupted polished water supply to the downstream users if any of the existing pumps need to be taken offline for maintenance.

The intent is that if a HAZOP study scenario is deemed to have acceptable Risk then there is a high confidence that additional Risk reduction is not required. HAZOP/LOPA scenarios that are deemed to have an unacceptable Risk require either implementation of additional IPLs, more detailed calculations to confirm the actual severity, or a detailed Consequence Model or Quantitative Analysis technique.

HAZOP Methodology

The Hazard and Operability (HAZOP) Study is a systematic and structured evaluation of a planned or existing operation, with the objective of identifying and evaluating potential hazards during both the design and operational stages. The present study has been undertaken by a collective of engineers possessing a wide range of specialized knowledge and skills. The research team conducts a thorough analysis of discrete components of a plant, system, or operation, commonly known as nodes. They evaluate the likelihood of any deviations from the intended operation and assess their potential consequences in light of any existing safeguards.

The assessment of the impact of identified hazards on safety, assets, and the environment is conducted. The HAZOP methodology is a brainstorming technique that is driven by the use of guidewords. The team members make contributions based on their combined experience and knowledge gained from previous projects.

The HAZOP analysis procedure entails the documentation of identified hazards, with the exclusion of proposing solutions unless a definitive solution is evident. Possible resolutions may include additional measures or operational protocols that are considered necessary. The study record functions as a tool for identifying the Health, Safety, and Environment (HSE) concerns that require resolution throughout the project.

The primary procedures encompassed in a Hazard and Operability (HAZOP) analysis are outlined as follows:

  • Explain overall design & Select the node (line, equipment or a system) on the P&ID;
  • Examine and agree on the design intent;
  • Select a parameter using the description and design intention;
  • Select a guide word Apply the guide word (and to each of its characteristics as relevant) to obtain a specific deviation
  • Investigate the causes, consequences and protection consequences
  • Suggest recommendations/actions, should the safeguards be inadequate; Assess severity, likelihood and assign Risk Rank for each consequence and provide recommendation
  • Repeat steps 3 to 6 for each deviation

Repeat steps from one (1) to seven (7) on the next node until all the nodes are covered.

The objectives of the HAZOP study are:

  • The task at hand involves the identification and assessment of potential hazards and risks that may be linked to process facilities.
  • Identify operability and maintenance issues
  • Comprehend these perils/challenges and assess their probable outcomes.
  • Suggest additional measures or protocols that are considered necessary.

These steps will lead to a better design/ operation of the facility to mitigate the potential hazards identified.

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 document pertains to the guidelines, operating procedures, and health, safety, and environmental (HSE) philosophies of the company.
  • Incident reports
  • Facility Risk Register

The HAZOP analysis proceeds systematically by examining each node of the plant in succession. The Facilitator makes the selection of the node sizes and the route through the plant before the study. The node ought to be explicated in terms of:

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

Guidewords are simple terms or expressions that are used to define or quantify the objective and associated parameters, with the intention of suggesting variations.

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

Typical parameters/elements considered for HAZOP are as follows

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

Deviation refers to the instances where the process design intent is not followed.  The combination of parameters and guidewords in sequence are identified all the deviations (no flow, more temperature etc.). It is possible that there exists a noteworthy degree of overlap among the deviations under consideration, such as the possibility that the absence of flow could produce an effect equivalent to that of increased pressure.

The team will participate in a collective process of generating ideas to identify all possible factors that contribute to the observed deviation. It is imperative to thoroughly identify and discuss all potential causes, as the resulting consequences and necessary actions may vary significantly. Causes are inherently confined to the local context or limited to the specific node. If feasible, the information has been condensed and restricted to the specific topic being discussed.

There are three main classifications of causes, arranged in a descending order based on their likelihood.

  • Human error
  • Equipment failure
  • External events

It may be noted that “cause” in worksheet is explicitly worded including one tag. This statement encompasses additional associated labels for analogous apparatus. 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 important consequences anywhere in the facility, resulting from the cause are listed out. The description of worst-case consequences is predicated on the absence or malfunctioning of any protective measures.

Safeguards refer to control measures that serve to prevent the occurrence of a cause, notify the operator of any deviations that may arise, and mitigate the potential consequences in the event that the cause does occur.

  • Included in this category are various systems, engineered designs, and written procedures that are specifically developed to mitigate the risk of a catastrophic release of hazardous or flammable substances.
  • Those systems are specifically engineered to identify and provide timely notification subsequent to the onset of a hazardous or combustible substance discharge.
  • It pertains to a collection of protocols or documented measures that are designed to mitigate the consequences of a release of a hazardous or flammable substance.

It is further noted that, positive isolation procedure is followed while handling over any facility for maintenance work such as control valve maintenance, which requires breaking the flange, etc. Once the key safeguards are listed, the team then evaluates the listed Safeguards based on adequacy to eliminate or maintain the potential risks within tolerable limits.

During the HAZOP session, the study team engaged in a systematic brainstorming process to evaluate the process under review in the scheduled meeting. The review was structured by utilizing a set of Guidewords. The study team is composed of individuals representing a variety of departments/specialties.

The following procedure is adopted during the HAZOP workshop:

  • Selecting a Node (i.e. vessel or line) to be assessed;
  • Describing the purpose and design of the Node by a Process Engineer or an Operation Representative;
  • Identifying a potential Deviation that may occur within that Node using a Guideword and
  • Parameter;
  • The process of identifying and evaluating the causes for deviations from the design intent.
  • Evaluating the potential Consequences from the Deviations addressed, without considering any
  • Safeguards in place;
  • This section focuses on the identification of safeguards implemented to prevent the occurrence of a failure scenario or to mitigate its consequences.
  • Recommendations are raised to mitigate the Consequences further, wherever required.