klj_sil assessment report_26 july 2014
DESCRIPTION
Safety Integrity LevelTRANSCRIPT
SIL Assessment for Chlorinated Paraffin Wax Plant
KLJ Organic - Qatar W.L.L
Prepared For:
KLJ Organic - Qatar W.L.L
Project Location:
Mesaieed Industrial City
Prepared By:
Velosi Certification LLC
26-Jul-14
SIL ASSESSMENT REPORT Page 2 of 20
Report Type: SIL Assessment for Chlorinated Paraffin Wax Plant
Project Title: Chlorinated Paraffin Wax Plant SIL Assessment
Client Company Name: KLJ Organic - Qatar W.L.L
Issued By: Mike Snakard
Date: 26-Jul-14
Document Production & Approval Record
Issue No. Name Signature Date Title
Prepared by Syed Quraishy
26-Jul-14 HSE Consultant
Revised by Mike Snakard
26-Jul-14 SIL Assessment Chairman
Approved by Mark Kenyon
pp
26-Jul-14 Regional HSE Consultancy Manager
Document Revision Record
Issue No. Date Details of Revision
Rev 0 26-Jul-14 Initial report
COPYRIGHT
© This report is the copyright of Velosi Certification LLC. Any unauthorised reproduction or
usage by any person other than the addressee is strictly prohibited.
SIL ASSESSMENT REPORT Page 3 of 20
LIMITATIONS
VELOSI Certification LLC (Applus+ VELOSI) has prepared this report for the sole use of KLJ
Organics Qatar in accordance with the agreement under which our services were performed.
No other warranty, expressed or implied, is made as to the professional advice included in
this report or any other services provided by us. This report may not be relied upon by any
other party without the prior and express written agreement of Applus+ VELOSI.
Unless otherwise stated in this report, the assessments made assume that the sites and
facilities will be used for their current intended purpose without significant change. The
conclusions and recommendations contained in this report are based upon information
provided by others and upon the assumption that all relevant information has been provided
by those parties from whom it has been requested. Information obtained from third parties
has not been independently verified by Applus+ VELOSI, unless otherwise stated in the
report.
Where inspections have been carried out, these have been restricted to a level of detail
required to achieve the stated objectives of the services. The results of any measurements
taken may vary spatially or with time.
SIL ASSESSMENT REPORT Page 4 of 20
LIST OF ABBREVIATIONS/NOMENCLATURE
API : American Petroleum Institute
CL2 : Chlorine Gas
CPW : Chlorinated Paraffin Wax
DP : Design Pressure
DT : Design Temperature
EIA : Environmental Impact Assessment
EMS : Emergency Management System
ESD : Emergency Shutdown
FRP : Fibreglass Reinforced Plastic
H2 : Hydrogen Gas
HAZID : Hazard Identification Study
HAZOP : Hazard & Operability Study
HCl : Hydrochloric Acid
HSE : Health Safety & Environment
IPF : Instrumented Protective Functions
ITM : Inspection Testing and Maintenance
MOE : Ministry Of Environment
MIC : Mesaieed Industrial City
N2 : Nitrogen
NFPA : (US) National Fire Protection Association
PPE : Personnel Protective Equipment
PTW : Permit To Work
PVC : Polyvinyl Chloride
QP : Qatar Petroleum
QRA : Quantitative Risk Assessment
SIL : Safety Integrity Level
SIMOPs : Simultaneous Operations
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SOP(s) : Standard Operating Procedure(s)
STEL : Short Term Exposure Limit
TLV : Threshold Limit Value
UPS : Uninterruptable Power Supply
SIL ASSESSMENT REPORT Page 6 of 20
Table of Contents
1 EXECUTIVE SUMMARY...................................................................................... 7
2 INTRODUCTION ............................................................................................... 8
2.1 STUDY INTRODUCTION .......................................................................................... 8
2.2 REPORT OVERVIEW ............................................................................................... 8
2.3 TEAM COMPOSITION ............................................................................................. 8
3 BACKGROUND, OBJECTIVE & SCOPE .............................................................. 10
3.1 DESCRIPTION OF FACILITY ..................................................................................... 10
3.2 OBJECTIVES OF THE SIL ASSESSMENT ...................................................................... 10
3.3 SIL ASSESSMENT METHODOLOGY ............................................................................ 10
3.3.1 Consequence/Severity ................................................................................ 11
3.3.2 Occupancy ................................................................................................. 12
3.3.3 Probability of Avoiding the Hazard ............................................................... 12
3.3.4 Demand Rate ............................................................................................. 13
3.3.5 Calibrated Risk Graph ................................................................................. 13
4 SIL ASSESSMENT STUDY FINDINGS .............................................................. 16
5 RECOMMENDED FOLLOW UP ACTIONS .......................................................... 18
6 CONCLUSIONS ............................................................................................... 19
APPENDIX A ......................................................................................................... 19
SIL ASSESSMENT REPORT Page 7 of 20
EXECUTIVE SUMMARY
This report describes the scope, methodology, findings and recommendations from the
Safety Integrity Level (SIL) Assessment workshop conducted for the KLJ Organics Qatar
WLL (KLJ) plant to be constructed in Mesaieed Industrial City, Qatar. The primary objective
of this study was to determine the appropriate level of reliability needed to manage the risks
associated with each Safety Instrumented Function (SIF) identified in the HAZOP review
completed for the project.
The SIL Assessment Review Meeting was held on 1st July 2014 and facilitated by Mr. Mike
Snakard via video conference call. The meeting included the participation of key
representatives from QP, and KLJ. Support from the additional KLJ engineering team
members was solicited via video conference as required. This report documents the
discussions held and records the proceedings of the SIL Assessment workshop.
The SIL Assessment workshop analysed the reliability requirements of the eight (8) Safety
Instrumented Functions (SIF’s) identified during the HAZOP review Workshop. During the
SIL Assessment, the following two recommendations were made:
KLJ to consider moving the ESDV 2 and downstream manual isolation valve to
the inlet nozzle of the liquefier to eliminate the piping section downstream of the
ESDV. Note: this will also aid in avoiding a Low Low Pressure shutdown when
the valves are closed.
KLJ to consider adding a High High rate of change alarm on WIZ-540A to avoid
the tripping of ESDV 4 / 6 / 8. Alarm will notify personnel in the building of the
potential for a leak/rupture in the storage tank and instruct them of the potential
need to evacuate the building (secondary protection in the area includes area gas
detection that will alarm on detection of Cl2 gas).
SIL ASSESSMENT REPORT Page 8 of 20
1 INTRODUCTION
1.1 Study Introduction
A one-day Safety Integrity Level (SIL) Assessment Workshop was conducted for the KLJ
Organics Qatar WLL (KLJ) Chloro Alkali Plant to be constructed in Mesaieed Industrial City,
Qatar. This report describes the results of the SIL Assessment Study performed by Applus+
VELOSI for KLJ.
The SIL Assessment Review workshop was held on 1st July 2014 in the KLJ 3rd floor
conference room, (SIL Assessment facilitation was done via video conference call). The
meeting involved the participation of key representatives from QP, and KLJ. Applus+
VELOSI provided the SIL Workshop Chairman and Scribe. This report documents the
discussions held and records the proceedings of the SIL Assessment workshop.
The SIL Assessment workshop analysed the reliability requirements of the eight (8) Safety
Instrumented Functions (SIF’s) identified during the HAZOP review Workshop. The SIFs
studied in the SIL Assessment are listed below:
SIF 1:Electrolyzer Outlet Low Low Differential Pressure shuts off Rectifier and close
ESDVs 1A and 1B on momentary delay;
SIF 2: Chlorine Compressor Low Low Discharge Pressure shuts off rectifier and shut
of ESDV’s 1B, 2, 4, 6 and 8;
SIF 3: Chlorine Gas Separator Low Low pressure in vapor outlet line Closes ESDV 2
and 3;
SIF 4: Liquid Chlorine Storage Tanks High High Level closed ESDVs 4;
SIF 5: Liquid Chlorine Storage Tanks High High Level closed ESDVs 6;
SIF 6:Liquid Chlorine Storage Tanks High High Level closed ESDVs 8;
SIF 7: Chlorine Vaporizer outlet Low Low Pressure Closed ESVDs 5, 7, 9, 10 and 11
SIF 8: Activation of Chlorine Area Gas Detection in the Liquid Chlorine Storage
Building
1.2 Report Overview
This report provides a brief description of the KLJ plant facility, the SIL Assessment
methodology employed, and the discussions and findings of the SIL Assessment workshop.
Section 3 describes the scope and objectives of the assessment, methodology employed.
Section 4 and 5 list up specifics findings from this study and recommendations respectively.
Finally, Section 6 gives concluding remarks about the study.
The worksheets documenting the discussions and findings of the SIL Assessment Workshop
are provided in the appendices along with additional reference information.
1.3 Team Composition
A team knowledgeable in the design and operation of the project and equipment as well as
in the SIL Assessment methodology was assembled to conduct the study. The team
consisted of representatives from KLJ, and Qatar Petroleum (QP). Applus+ VELOSI provided
the SIL Workshop chairperson who also acted as scribed. The team assessed the reliability
SIL ASSESSMENT REPORT Page 9 of 20
requirements of each SIF using a structured SIL Assessment methodology. Discussions in
the Workshops were recorded in PHAPro 8using the Calibrated Risk Graph Method format
consistent with the QP Guidelines for Safety Integrity Level Review, SP-GDL-S-030.
The display of the spreadsheet was projected onto a screen in the conference room to
enable the entire team to view the study documentation in real-time. A list of Workshop
attendees is documented in this report provided in Appendix A.
SIL ASSESSMENT REPORT Page 10 of 20
2 BACKGROUND, OBJECTIVE & SCOPE
2.1 Description of Facility
KLJ Organic Qatar W.L.L. (KLJ) is a joint venture company owned by Qatar Industrial
Manufacturing Co. (QIMC) of Qatar and KLJ Organic Ltd. of India. KLJ has acquired a plot
of land in Mesaieed Industrial City (MIC), Qatar to construct a Chlorinated Paraffin Wax
(CPW) plant. The facility will also produce caustic soda, hydrochloric acid, calcium chloride
and sodium hypochlorite ads by-products and co-products.
The plant will have a capacity of approximately 54,500 tons/year of CPW and will produce
66,000 tons/year of caustic soda prills, 97,450 tons/year of 32% HCl, 28,000 tons/year of
calcium chloride and 6,600 tons/year of sodium hypochlorite.
2.2 Objectives of the SIL Assessment
Applus+ VELOSI has completed a HAZOP and QRA for the Chlorinated Paraffin Wax project
KLJ plans to constructed in Mesaieed Industrial City, Qatar. As part of that HAZOP review
effort, eight (8) Safety Instrumented Functions (SIF’s) were identified. These SIF’s require
further assessment to define the reliability requirements of these loops. A SIL Verification
will then be completed during detailed engineering to confirm that the instruments selected
for these SIF’s achieve the required SIL rating (as defined in the SIL Assessment).
2.3 SIL Assessment Methodology
Safety Integrity Levels (SILs) were assigned in the SIL Assessment Workshop using the
Calibrated Risk Graph method following IEC 61511-3. The Calibrated Risk Graph method
provides a correlation of Risk Severity and Risk Likelihood to the SIL Assessment process in
accordance with the QP Corporate Risk Criteria.
For each SIF, the design intent was documented to identify the purpose of the safety
function. Workshop participants then determined the demand scenario by assessing the
potential consequences should the safety function under evaluation fail and the layers of
protection in place to protect against those consequences.
Risk rankings were assessed based on the following four parameters:
Consequence or Severity of the hazardous situation for personnel safety,
environment or economic / asset loss (S, E & A respectively);
Occupancy (probability that the exposed area is occupied) (F);
Probability of avoiding the hazardous situation (P); and
Demand rate (number of times per year that the hazardous situation would
occur in the absence of the safety instrumented function being considered)
(W).
Table 2-1 on the following page gives a description of the risk graph parameters listed
above.
SIL ASSESSMENT REPORT Page 11 of 20
Table 2-1: Description of process industry risk graph parameters
Parameter Description
Severity S Number of fatalities and / or serious injuries, environmental effect and damage to the asset / production likely to result from the occurrence of the hazardous event
Occupancy F Probability that the exposed area is occupied at the time the area is occupied at the time of the hazardous event. This should take into account the possibility of an increase likelihood of persons being in the exposed area in order to investigate abnormal situations which may exist during the build-up to the hazardous event (consider also if this changes the C parameter)
Probability of avoiding the hazard
P The probability that exposed persons are able to avoid the hazardous situation which exists if the safety instrumented function fails on demand. This depends on there being independent methods of alerting the exposed persons to the hazard prior to the hazard occurring and there being methods of escape
Demand Rate
W The number of times per year that the hazardous event would occur in the absence of the safety instrumented function under consideration. This can be determined by considering all failure which can lead to the hazardous event and estimating the overall rate of occurrence. Other protection layers should be included in the consideration
2.3.1 Consequence/Severity
The Consequence or Severity to define the SIL required for a SIF is defined against the
following criteria:
Impact of incident on Personnel Health and Safety
Impact of incident on Environment
Impact of incident on Asset, i.e. production and equipment loss
(commercial loss)
The following Table 2-2 provides the calibrated Consequence or Severity criteria for SIL in
terms of Personnel Health and Safety, Environmental and Assets in accordance with QP
Corporate Risk Assessment Matrix.
Table 2-2: Consequence or Severity SIL based on QP Risk Assessment Matrix
Risk Parameter Personnel Safety Environment Asset
Consequence Risk Parameter
CA (S1 / E1 / A1) Minor Injury or health effects
Minor effect Minor damage (<QR 350,000)
CB (S2 / E2 / A2) Major Injury or health effects
Localized effect Local Damage (<QR 3,500,000)
CC (S3 / E3 / A3) Single Fatality or Permanent Total
Disability
Major effect Major Damage (<QR 35,000,000)
CD (S4 / E4 / A4) Multiple Fatalities Massive effect Extensive damage (>QR 35,000,000)
SIL ASSESSMENT REPORT Page 12 of 20
2.3.2 Occupancy
Once the consequence was defined, the concept of vulnerability was introduced to modify
the consequence parameter, since in many instances a failure does relate to an immediate
fatality.
A receptor’s vulnerability is an important consideration in risk analysis because the dose
received by the receptor is sometimes not large enough to cause fatality. A receptor’s
vulnerability to a consequence is a function of the concentration of the hazard to which the
receptor is exposed to and the duration of the exposure. In this case, the worst case of
receptor exposure during the build up to the event is to be considered. This is defined by
the parameter ‘Occupancy (F)’, which defines the exposure levels of the receptor in the
hazardous zone that is discussed. Table 2-3 below provides the levels of occupancy that was
considered while defining SIL.
Table 2-3: Occupancy Levels
Risk Parameter Description
Occupancy (F) i.e. Frequency of exposure to hazardous zone
F1 Rare to more frequent exposure in the hazardous zone. Occupancy less than 0.1 (10% of working shift)
F2 Frequent to permanent exposure in the hazardous zone
2.3.3 Probability of Avoiding the Hazard
Once the occupancy is defined, the concept of probability of avoiding the hazardous event is
introduced. This is because in many instances even though the receptor is more vulnerable
to the hazard; it can be prevented by alerting the receptor and initiating the shutdown
systems such that the hazard can be avoided or enable the escape of receptor from the
hazardous zone to a safe area. This is defined by the parameter ‘Probability of avoidance
(P)’. Table 2-4 below provides the levels of probability of avoidance that will be considered
while defining SIL.
Table 2-4: Probability of avoiding the hazard
Risk Parameter Description Comment
Probability of Avoidance (PA) i.e. Probability of avoiding the
hazardous event, if the protection
system fails to operate
P1 Adopted if avoidance is possible - through pre-alarms, independent shutdown facilities, adequate response time or evacuation possibilities
PA should only be selected if all the following are true: - Facilities are provided to alert the operator that the SIS has failed; - Independent facilities are provided to shut down such that the hazard can be avoided or which enable all persons to escape to a safe area; - The time between the operator being alerted and a hazardous event occurring exceeds 1 hour or is definitely sufficient for the necessary actions.
P2 Adopted if all or any of the conditions are not satisfied
If conditions listed above in the PA are not satisfied
SIL ASSESSMENT REPORT Page 13 of 20
2.3.4 Demand Rate
Once all other factors have been defined, the Demand Rate is then identified and used to
define the demand requirement of the Safety Instrumented Function. Likelihood or Demand
rate is defined as ‘the number of times per year that the hazardous event would occur in the
absence of the safety instrumented function under consideration’. To determine the
Likelihood or Demand rate, it is necessary to consider all sources of failure that can lead to
one hazardous event. In determining the Likelihood or Demand rate, limited credit was
allowed for control system performance and intervention. Table 2-5 defines the Likelihood or
Demand rate parameters used in the SIL Assessment.
Table 2-5: Demand Rate
Demand Rate Classification based on IEC 61511
Demand rate (W) Likelihood of the unwanted occurrence
W1 A very slight probability that the unwanted occurrence will happen and only a few unwanted occurrences are likely. Once in every 30 to 100 years.
W2 A slight probability that the unwanted occurrence will happen and few unwanted occurrences are likely. Once in every three to 30 years.
W3 A relatively high probability that the unwanted occurrence will happen and frequent unwanted occurrences are likely. More than once in every one to three years.
2.3.5 Calibrated Risk Graph
PHA Pro 7 software was used for documenting the SIL Assignment. The parameters in
above sections like ‘Severity’, ‘Occupancy’, ‘Possibility of Avoidance' and ‘Demand Rate’ were
used as inputs to the Risk Graph and were applied in accordance with the guidelines given
below. The output, which was determined by software following the sequential application
of these parameters, is the SIL rating for each SIF assessed. The SIL required to ensure that
the system/loop under review can meet the design intent were classified as:
No requirements;
a (no special safety requirements);
SIL 1 (target average probability of Failure on Demand of≥ 10-2 to > 10-1;
SIL 2 (target average probability of Failure on Demand of≥ 10-3 to > 10-2;
SIL 3 (target average probability of Failure on Demand of≥ 10-4 to > 10-3;
SIL 4 (target average probability of Failure on Demand of≥ 10-5 to > 10-4;
B (the risk is unacceptably high and requires redesign or a single SIF is not
sufficient).
The Risk Graph is calibrated in accordance with the QP Risk Assessment Matrix and IEC
61511 requirements which is presented in Figures 2-1 through 2-3, below.
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Figure 2-1: Calibrated Risk Graph/Matrix – Personnel Safety
Figure 2-2: Calibrated Risk Graph/Matrix – Environmental Loss
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Figure 2-3: Calibrated Risk Graph/Matrix – Asset or Economic Loss
Given that the SIFs identified during the HAZOP review focused on the prevention of Loss of
Containment of Chlorine, Personnel Safety was the controlling concern and thus all risk
rankings recorded in the SIL Assessment were done using the Calibrated Risk Graph/Matrix
– Personnel Safety.
SIL ASSESSMENT REPORT Page 16 of 20
3 SIL ASSESSMENT STUDY FINDINGS
The SIL Assessment findings and session proceedings were recorded using Dyadem’s PHAPro 8 software and are listed in the worksheets, below.
Node: 1. Chlorine System within the Caustic Process Area
Deviation: 1.
Type: Drawings:
Design Conditions/Parameters: Equipment ID:
SIL determination
SIF SIF Status Safeguards (excluding SIF under
consideration)
Risk Graph (Qualitative method) - Initial Recommendations
Risk Graph (Qualitative method) - Final
C F P W SIL C F P W SIL
1.
SIF 1: Electrolyzer Outlet Low Low Differential Pressure shuts off Rectifier and close ESDVs 1A and 1B on momentary delay
Rec 1 Mechanical failure of Electrolyzer membranes in the event of FB rupture or 100 mm hole due to rapid drop in Chlorine pressure causing high differential pressure across Hydrogen & Chlorine sides of the membrane (Electrolyzer damage estimated within 10 seconds).
S3 (CC) F1 P1 W2 SIL 1 S3 (CC) F1 P1 W2 SIL 1
2.
PdZA-229 Alarms High & Low and Shuts of rectifier on High High or Low Low Differential Pressure.
3.
Area Gas Detection
4.
High and High High alarms (226 & 228 and 218 & 216) & shutdowns on H2 & Cl2 - No credit taken - common logic solver [Revalidated]
2.
SIF 2: Chlorine Compressor Low Low Discharge Pressure shuts off rectifier and shut of ESDVs 1B, 2, 4, 6 and 8
Rec 1.
PIA-514 on the outlet of the Mist Eliminator Alarms Low in the DCS - No credit taken for alarm only
S3 (CC) F2 P1 W2 SIL 2 KLJ to consider moving the ESDV 2 and downstream manual isolation valve to the inlet nozzle of the liquefier to eliminate the piping section downstream of the ESDV. Note: this will also aid in avoiding a Low Low Pressure shutdown when the valves are closed
S3 (CC) F2 P1 W2 SIL 2
2.
PIA-510 on the outlet of the Mist Eliminator Alarms Low in the DCS - No credit taken for alarm only
3.
Area Gas Detection
3.
SIF 3: Chlorine Gas Separator Low Low pressure in vapor outlet line Closes ESDV 2 and 3
Rec 1.
PICA-530 Alarms Low in the DCS - No credit taken for alarm only
S3 (CC) F1 P1 W2 SIL 1 S3 (CC) F1 P1 W2 SIL 1
2.
On imbalance of H2 to Cl2 ratio in the HCl plant (e.g.: caused by medium or large leak / rupture of the Cl2 piping) HCl plant will extinguish the flame in the burner for the synthesis reactor which will in turn close the pressure control valve PV-530A
SIL ASSESSMENT REPORT Page 17 of 20
Node: 1. Chlorine System within the Caustic Process Area
Deviation: 1.
Type: Drawings:
Design Conditions/Parameters: Equipment ID:
SIL determination
SIF SIF Status Safeguards (excluding SIF under
consideration)
Risk Graph (Qualitative method) - Initial Recommendations
Risk Graph (Qualitative method) - Final
C F P W SIL C F P W SIL
3.
Area Gas Detection
4.
SIF 4 / 5/ 6: Liquid Chlorine Storage Tanks High High Level closed ESDVs 4 or 6 or 8
Rec 1.
Secondary containment (Dike) sloped to fully enclosed containment sump vented to neutralization system on activation of Area Chlorine Gas Detection.
S4 (CD) F1 P2 W1 SIL 2 • KLJ to consider adding a High High rate of change alarm on WIZ-540A to avoid the tripping of ESDV 4 / 6 / 8. Alarm will notify personnel in the building of the potential for a leak / rupture in the storage tank and instruct them of the potential need to evacuate the building (secondary protection in the area includes area gas detection that will alarm on detection of Cl2 gas).
S4 (CD) F1 P2 W1 SIL 2
2.
Liquid storage tanks installed within an enclosed building which is vented to the neutralization system.
3.
Area Gas Detection 2oo5
5.
SIF 7: Chlorine Vaporizer outlet Low Low Pressure Closed ESVDs 5, 7, 9, 10 and 11
Rec 1.
On Low pressure (PAL) PIC-554 opens PV-554 and routes gas to the neutralization system
S3 (CC) F1 P1 W2 SIL 1 S3 (CC) F1 P1 W2 SIL 1
2.
Area Gas Detection 2oo3
3.
Piping within the isolatable section from the Vaporizer to the CPW plant contained within the Chlorine Vaporizer Building and the secondary containment ducting
6.
SIF 8: Activation of Chlorine Area Gas Detection in the Liquid Chlorine Storage Building
Rec 1.
FALL or FAHH on FICA-544 A/B to trip Pump P-544A/B on activation.
S4 (CD) F1 P1 W2 SIL 2 S4 (CD) F1 P1 W2 SIL 2
2.
Liquid storage tanks installed within an enclosed building which is vented to the neutralization system.
SIL ASSESSMENT REPORT Page 18 of 20
5 RECOMMENDATIONS
The following recommendations were identified in the SIL Assessment:
KLJ to consider moving the ESDV 2 and downstream manual isolation valve
to the inlet nozzle of the liquefier to eliminate the piping section
downstream of the ESDV. Note: this will also aid in avoiding a Low Low
Pressure shutdown when the valves are closed.
KLJ to consider adding a High High rate of change alarm on WIZ-540A to
avoid the tripping of ESDV 4 / 6 / 8. Alarm will notify personnel in the
building of the potential for a leak / rupture in the storage tank and instruct
them of the potential need to evacuate the building (secondary protection in
the area includes area gas detection that will alarm on detection of Cl2 gas).
It is expected that KLJ will address and close out each of these recommendations prior to
start-up of the plant.
SIL ASSESSMENT REPORT Page 19 of 20
6 CONCLUSIONS
The SIL Assessment was completed for eight (8) Safety Instrumented Functions (SIF’s)
identified during the HAZOP Review Workshop. As an aftermath of the assessment, it was
determined by the SIL Assessment participants that the required reliability for each of the
SIFs falls with the SIL 1 or SIL 2 classification, as shown in the Table 6-1, below.
Safety Instrumented Function SIL Rating
SIF 1: Electrolyzer Outlet Low Low Differential Pressure shuts off Rectifier and close ESDVs 1A and 1B on momentary delay;
SIL 1
SIF 2: Chlorine Compressor Low Low Discharge Pressure shuts off rectifier and shut of ESDV’s 1B, 2, 4, 6 and 8;
SIL 2
SIF 3: Chlorine Gas Separator Low Low pressure in vapor outlet line Closes ESDV 2 and 3;
SIL 1
SIF 4: Liquid Chlorine Storage Tanks High High Level closed ESDVs 4; SIL 2
SIF 5: Liquid Chlorine Storage Tanks High High Level closed ESDVs 6; SIL 1
SIF 6:Liquid Chlorine Storage Tanks High High Level closed ESDVs 8; SIL 2
SIF 7: Chlorine Vaporizer outlet Low Low Pressure Closed ESVDs 5, 7, 9, 10 and 11
SIL 1
SIF 8: Activation of Chlorine Area Gas Detection in the Liquid Chlorine Storage Building
SIL 2
The SIL Assignments above, identify the minimum required levels of reliability for each SIF.
The actual levels of reliability will then be completed for each SIF during the SIL Verification
study to be completed in accordance with Qatar Petroleum SIL Guidelines (SP-GDL-S-030).
SIL ASSESSMENT REPORT Page 20 of 20
APPENDIX A: LIST OF SIL ASSESSMENT ATTENDEES
Mike Snakard SIL Assessment Chairman Applus+ VELOSI
Manoj Srivastava KLJ Project Manager KLJ
U. C. Tiwari KLJ Engineering Lead KLJ
Kirti Pratap KLJ Project Team KLJ
Shipra QIMCO Project Engineer QIMCO
Karthik Subbiah A/CHR, Acting Head of HSE Risk QP
Giri Mangalam CHR/4, Risk Assessment Specialist QP
Ganesh Nilangekar Sr Fire Prevention Eng, Industrial Cities QP