SAFETY IN COMMISSIONING

AND

START UP OPERATIONS

S.K. Ghosh, IOCLS.M. Vaidya, IOCL

12th August, 2010

PLANT START-UP AND COMMISSIONING

Plant commissioning is the first of many start-ups;

Potential hazardous : Ability to operate not proven;

Many unknown factors.

Expensive;

ROI severely affected;

Financial viability under question.

ELEMENTS OF SUCCESSFUL COMMISSIONING

MANPOWER DEPLOYMENT

Multi-disciplinary core team including team leader 2 years prior to commissioning;

Balance team deployment at least 1 year prior to commissioning;

Blend of experienced and new in the ratio of 3:1;

Deploying few senior members of project team for maintenance jobs;

Team leader should able to command the resources;

Top management support to the team.

TRAINING

Extensive theoretical and field training on similar plants;

Training at critical equipment vendors workshop;

Training simulator must be placed 1 year before commissioning;

Structured training on emergency responses, handling of hazardous chemicals;

Licensor training;

Inducting commissioning group for HAZOP;

Mock operational drills.

The Process;

Conditioning and Special Equipment;

Starting Procedures;

Limits Of Operation;

Shutdown Procedures;

Develop work and safety procedures;

Specify typical maintenance activities;

Select and purchase maintenance supplies and spare parts;

Negotiate with vendors and contractors;

Keep maintenance records;

Make detailed designs of any changes and additions made

Technical manual for process technology and equipment SOPs’;

Safety valve and rupture disk manual, listing the design basis for each safety device, and giving the procedure for taking it out of service;

Training manual detailing the program for new personnel;

Safety manual depicting policies, proceduresemergency response etc.;

Maintenance procedures specific to the new plant;

Change Management .

PRE-COMMISSIONING

Pre-commissioning activities overlap mechanical completion;

Plant is segregated into manageable systems / sub-systems / flushing loops;

Checking of design conformity;

Checking status of Electrical, Mechanical & Instrument Installations;

No Load / Load run of rotary equipment;

Flushing, Cleaning, Drying etc.;

Loop checking should also start after flushing.

Why to do?

When to do?

Who is to do?

How to do?

What to do?

CHECK LISTING

To be done as per system/sub-systems;

System is as per P&ID;

Identifying skewness of Flanges;

Short/Long Bolting;

Use of proper gasket – color codes;

Support systems.

Contd..

WHAT TO DO IN CHECK LISTING?

Location of drains/vents;

Column/Vessels – internals as per drawing;

Positioning of instruments;

Valve / CV’s installations;

WHAT TO DO IN CHECK LISTING?

Safety checks by Licensors – compliance;

In-house multidisciplinary audit as per OISD Format –compliance;

OISD Audit - compliance;

In-house multidisciplinary audit before feed-in;

Adherence to Plant/Equipment check list;

*External audit is done e.g. Shell Global did for PNC.

SEQUENTIAL PRE-START UP SAFETY CHECKSMULTI LAYER APPROACH

Construction as per design specification;

P&ID’s are complete;

System Protection – Interlocks/ ESD’s;

O&M & Safety system / Procedures /Documentation;

Training & its effectiveness;

Statutory compliances are met;

OBJECTIVE OF PRE-START UP SAFETY REVIEW

MINIMUM FACILITIES BEFORE START UP

Implementation of Work permit system;

Fire fighting facilities including positioning of extinguishers etc.;

Clearly defined emergency exits , with display boards;

Removal of debris / temporary structures and power connections;

Tested Paging systems & availability of Walkie –talkies;

Readiness of OWS /CRWS system with ETP in operation;

contd..

Availability of adequate PPE’s /First Aid boxes;

Judicious implementation of isolation scheme;

Properly stenciled Utility points with connecting hoses / lancers;

Unlocking of springs/ supports of all headers;

All gas / hydrocarbon detector’s are tested and kept on;

ESD ‘s are tested , documented and kept activated etc.;

Flare system is in position.

MINIMUM FACILITIES BEFORE START UP

Multidisciplinary group accountability for flange box-up/RTJ Joints;

Best leak test is at operating severity;

Hydrogen leakage should only be attended after depressurization ;

O2 content in N2 must be checked before inertisation;

Furnace lit up – with pilot only; keeping main valve blinded, purge fire box min. for 15mnts after each attempt;

Water /Condensate draining from all low points after gas backing up;

Condensate draining before charging steam headers;

contd..

OTHER START UP SAFETY ISSUES

Catalyst injection lines of petrochemical plants to be flushed with mineral oils;

In Naphtha Cracker Units important headers to be dried up to (-)65/70oC to avoid hydrate formation;

White oil tanks to be commissioned with at least 5 cm of water level;

Black oil tank should be commissioned dry, top M/H cover may be kept open if required;

Blind Lists are ready;

All safety valves, including TSV’s are in line;

contd..

OTHER START UP SAFETY ISSUES

LPD/HPV valves closed and capped;

All supports are un-locked;

Fine mesh strainer on rotary equipment;

ESD/De-pressurisation systems check;

Flare area to be cordoned – chances of fire balls during start up.

OTHER START UP SAFETY ISSUES