HAZOP Procedure [PDF]

Zitiervorschau

Jereh (Tianjin) O Oil & Gas En ngineering Co., C Ltd. J Jhal Magsi Gas G Field D Developmen nt Project Hazop H Repo ort

Annex A 1. HAZO OP Proce edure



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

1. Introduction 1.1 Objective The objective of the HAZOP review is to identify any potential hazard and check the unacceptable risk situation by process deviation. Basis: IEC 61882-2001. 1.2 Scope The HAZOP study shall include all P&IDs and other relevant documents. The process unit in this project shall be reviewed. In case of multiple trains of identical design, only a unique single train shall be subjected to HAZOP study. The recommendations generated are equally applicable to the other trains. The main working scope includes: ¾

Consequence analysis. Analyzing the hazards which possibly caused by malfunction or misoperation. The potential hazardous effects on staff, public, plant, equipment or environment will be considered.

¾

Existing safeguards analysis. Checking if the existing safeguards could prevent the hazards or mitigate the consequence to an acceptable level.

¾

Checking the safety for interface among the units.

¾

Ensuring the safe startup/ shutdown, safe operation and safe maintenance.

1.3 Definitions HAZOP

Hazard and Operability study

HSE

Health, Safety and Environment

P&ID

Piping& Instrument Diagram

PFD

Process Flow Diagram  

Owner

ENAR Petrotech Services (PVT.)Ltd. Oil & Gas Development Company Limited

Designer

Jereh (Tianjin) Oil & Gas Engineering Co., Ltd.

Contractor

Independent consultant company

2.Team composition and Responsibilities 2.1 Team composition The HAZOP study shall be carried out by a team of individuals with expertise in



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

different areas such as process, control, operation and safety.

Other individuals with

other specialties may be involved as required. The team should proceed with a well-structured brainstorming which guides the examination of each probable deviation from normal operating conditions at specified process nodes by referring to a set of guidewords. The participants will be entitled to raise the questions and recommendations. The team shall include, but not limited: •

HAZOP chairman

•

HAZOP scribe

•

Process Engineer

•

Instrument Engineer

•

Safety Engineer

•

Operators

•

Representatives of the owner

The following experts are expected to answer the relevant questions during the HAZOP session as required: Mechanical Engineers, Electric Engineers, Piping Engineers, General Plot Plan Engineers. 2.2 Responsibilities 2.2.1 HAZOP Chairman HAZOP chairman shall be independent from the project, which usually come from the contractor, i.e. third party agency. With good facilitating skill and experience he will guide the team, prompt input from team members, get consensus from the team. He will ensure that the discussion will follow the HAZOP procedure strictly, rather than divert to engineering solution discussion or any other topics. The main role of HAZOP chairman includes, but not limited: •

Review the required documents, check if the required information is

sufficient •

Schedule the HAZOP progress and facilitate the HAZOP session.

•

Select main deviation, define working scope, prepare the node



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

identification prior to the HAZOP study, define risk matrix and get consensus from HAZOP team. •

Facilitate the discussion with brainstorming, control the discussion scope

and progress. •

Summarize the discussion, get the consensus from team and supervise

the recording of study results. •

Review and issue final HAZOP report.

2.2.2 HAZOP Scribe The HAZOP Scribe shall be responsible for recording the HAZOP results in terms of defined report format, assisting HAZOP chairman to prepare the report. The HAZOP scribe shall be trained, with good understanding of HAZOP review procedure, HAZOP methodology, and technical terms. In this project, the HAZOP scribe is provided by contractor, i.e. a third party agency. If required, the HAZOP scribe shall also act as an interpreter for HAZOP chairman and other participating parties to ensure fully understanding of each party. 2.2.3 Other Team Members Other participants shall be selected based on their disciplines and experience. They will be guided by the HAZOP chairman, following the HAZOP procedure. The main roles (but not limited) are as follows: •

Identify the possible causes which lead to deviation

•

Analyze the consequences caused by deviation and differentiate the

safety issue or operation issue. •

Find the solution or generate the recommendation.

•

Ensure the feasibility of

solution, which will not generate the new

problems. •

Recommend further discussion for the unsure questions.

•

Ensure all meaningful results recorded.

3. HAZOP review procedure 3.1 Terms 3.1.1 Node



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

The process nodes are the locations on P&IDs, which mainly represent specific process system or units operated under the same operating condition. 3.1.2 Design Intention Description of how the process is expected to behave at the Study Line. This is qualitatively described as an activity (e.g., feed, reaction, sedimentation) and/or quantitatively in the process parameters, like temperature, flow rate, pressure, composition, etc. 3.1.3 Guidewords Guideword is a short word to create the imagination of a deviation of the intention. The mostly used set of Guidewords is: no, more, less, as well as, part of, other than and reverse. (See Annex 4.1) 3.1.4 Parameter The relevant parameter for the condition(s) of the process, e.g.flow, pressure, temperature, level, composition, etc. 3.1.5 Deviation A way in which the process conditions may depart from their intention. (See Annex 4.2) 3.1.6 Cause The reason why the deviation could occur. More causes can be identified for one deviation. 3.1.7 Consequence The

results

of

the

deviation,

in

case

it

occurs.

consequence

may

both comprise process hazards and operability problems, like plant shutdown. More consequences can follow from one cause and, in turn, one consequence can have several causes. 3.1.8 Safeguard Facilities that help to reduce the occurrence frequency of the deviation or to mitigate its consequences. 3.1.9 Actions Required / Recommendations



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

Activities identified during a HAZOP study for follow-up. These may comprise technical Improvements in the design, modifications in the status of drawings and process descriptions, procedural measures to be developed or further in-depth studies to be carried out. 3.2 HAZOP HAZOP is an abbreviation for Hazard and Operability study. HAZOP is a systematic procedure for determining dangers and operational problems of a plant. During the HAZOP session, the process will be defined into several nodes, which mainly represent specific process system or units operated under the same operating condition. 3.2.1 Node Identification The process nodes are the locations on P&IDs, which mainly represent specific process system or units operated under the same operating condition. Before starting the HAZOP session, the process nodes will be determined for investigation and uniquely numbered. Node selection shall be performed by HAZOP team leader (chairman) and agreed by all team members. 3.2.2 Design Intention The process engineer is responsible for explaining design intention of the process or nodes identified. Unless the team members clearly understand the design intention and parameters, the HAZOP study will be proceed effectively and the discussion is fruitful. The process engineer is required to explain the process before starting a new node session. 3.2.3 Guidewords + Parameter = Deviation For each node, the guideword is combined with parameters to generate the deviation, which depart from design intention. For examples, “No” + “Flow” = “ No Flow”. The main guidewords are listed as follows: z

NO

z

MORE

z

LESS



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

z

AS WELL AS

z

REVERSE

z

PART OF

z

OTHER THAN

Note˖HAZOP chairman is entitled to select other guidewords and parameters if required. 3.2.4 Cause analysis Guidewords combined with parameters could produce many deviations. However, only the meaningful deviation will be analyzed and recorded. The causes for deviation to analyze may occur actually with hazardous effect or operation issue. The recommendations are not necessarily made for all listed deviations. 3.2.5 Consequence and Safeguards For each applicable deviation, the team shall analyze the direct consequences, as well as indirect consequences. The existing safeguards incorporated in the design to prevent the hazards or mitigate the consequences caused by deviation shall also be discussed. If additional information is required for analyzing the consequences, the person responsible for collecting relevant information will be delegated and the further action will be recorded. 3.2.6 Reporting The Deviations, Causes, Consequences, Safeguards and Recommendations shall be recorded. HAZOP worksheet shall include all meaningful deviations. HAZOP scribe shall record the information confirmed and agreed by all team members. For each deviation, the guidewords, parameters, causes, consequences, safeguards, risk ranking and recommendations (if it is required) will be recorded precisely. The HAZOP scribe shall also provide the worksheet to the participant everyday after the meeting. 3.2.8 Identify the Responding Party All the recommendations generated during HAZOP shall be clear and practical. The responsible party will be defined during HAZOP, including individual or company. The responding party will implement the action required or recommendations.



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

3.3 HAZOP Report The HAZOP report is issued by the contractor. Before the report submitted, the contents will be reviewed and confirmed by the owner and Design Company. The main content includes: HAZOP Study Summary Introduction Team Composition HAZOP study objective and scope Process Description HAZOP Procedure Recommendations P&IDs used HAZOP worksheet 4. Annex 4.1 Guidewords and Definitions Guidewords none ,no, not

Definitions Negation of design intent

more

Quantitative increase

less

Quantitative decrease

As well as

Qualitative increase. For example, composition change, impurities. Qualitative decrease. For example, compositions change, lack of some

Part of composition. Reverse

Logical opposite of intent. For example, reverse flow. Complete substitution. For example, abnormal interruption, startup and

Other than shutdown, change in operation mode etc.



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

4.2 List of Deviations and possible causes Deviations

Causes Receipt reaction tank overpressure, gas plug, foreign body, scaling, deposition. Wrong path, pipeline rupture, major leak,

No flow equipment failure (isolation valves, pumps, containers, etc.), incorrect differential pressure, fault isolation, etc. Pump control instability, receipt reaction tank without pressure, More flow pumping, heat exchanger leakage, etc Siphon result, incorrect differential pressure, dual flow, Reverse flow emergency discharge, incorrect operation, etc. Pump failure, the reaction tank inlet pipe scaling, foreign body or sediments, weak pumping, cavitation, valve plug. Pipeline Less flow constraint, filter plugging, valve with dirt, orifice plates, density and viscosity problems, incorrect specification of process Surge problems, high pressure systems leakage, gas blow More pressure out(not fully discharge), PCV valve open failure Less pressure

Vacuum, undetected leaks, container emissions Environmental conditions, the exchange tubes fouling or failure,

More temperature

fire, water cooling failure, control error, heater control failure, internal fire, the reaction control failure, etc. Environmental conditions, reduce stress, dirt, or exchanger

Less temperature pipeline failure, heat loss, etc. High level

Level control failure, blocked pipes, pump failure, high inlet flow

Low level

Level control failure, such as no or low import flows

More viscosity

Incorrect material specifications, incorrect temperature

Less viscosity

Incorrect Material specifications, incorrect temperature



JHAL MAGSI GAS FIELD DEVELOPMENT PROJECT HAZOP STUDY REPORT

4.3 HAZOP Study Flow

Select a P&ID

Select a node

Describe the design intentions and operation requirements

Selecting guideword

Brainstorming the potential causes and consequences

Identify the safeguards

HAZOP Scribe

Not sufficient Recommendations

yes Completion date

yes other guidewords no yes

other nodes no

yes

no other PID



completed