Index

Node 1: Chlorine rail car, Parameter: Pressure
Node 1: Chlorine rail car, Parameter: Composition
Node 1: Chlorine rail car, Parameter: Level
Node 2: Cl2 liquid to vaporizer, Parameter: Flow
Node 2: Cl2 liquid to vaporizer, Parameter: Pressure
Node 2: Cl2 liquid to vaporizer, Parameter: Composition
Node 3: Cl2 vaporizer, Parameter: Flow
Node 3: Cl2 vaporizer, Parameter: Pressure
 

Worksheet - Cover Page

Printed: June 21, 2002, 2:34 PM
Company: Safetech
Location: Princeton, NJ
Facility: Princeton
PHA Method: HAZOP
PHA Type: Initial
Process:  
File Description: Chlorine Handling
Date:  
Process Description:  
Chemicals:  
Purpose:  
Scope:  
Objectives:  
Project Notes:  
Filters: None
 
PHAWorks by Primatech Inc.

Worksheet

Page: 1
Company: Safetech
Facility: Princeton

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (1) Chlorine rail car
Drawings:  CLC/01-07-66
Parameter:  Pressure
Intention:  Normal operation is 100 - 150 psig. Target pressure is 125 psig.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
More Higher Pressure 1. Fire exposure 1.1. Potential overpressurization of rail car resulting in release of chlorine. 1.1.1. Rail cars provided with relief valve. 1 4 4  
 :No recommendations  
1.1.2. Rail cars insulated
1.2. Potential rupture of the rail car if the rail car relief valve fails. 1.2.1. Location of rail car minimizes likelihood of exposure. 1 5 5 :No recommendations
2. High ambient temperature 2.1. Potential increase in pressure. Not likely to approach rated pressure of rail car. 2.1.1. Rail cars insulated 5 1 5 :No recommendations
2.1.2. Location of rail car minimizes likelihood of exposure.
2.1.3. Pressure indicator, PI-1.
Less Lower Pressure 3. Relief valve RV-25 fails open 3.1. Potential exposure of personnel and potential offsite impact 3.1.1. Railcar emergency leak patch kit is available on site. 1 4 4 3.1.1. Consider conducting a failure modes and effects analysis (FMEA) of a typical pressure relief valve. PWP
3.1.2. Pressure indicator, PI-1.
4. Empty rail car 4.1. Delay in treating 4.1.1. Rail car is weighed upon receipt 5 3 9 :No further recommendations  
5. Sudden change in ambient temperature 5.1. Potential for too low flow to the treatment system 5.1.1. Rail cars insulated 5 2 8 :No further recommendations
 

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (1) Chlorine rail car
Drawings:  CLC/01-07-66
Parameter:  Composition
Intention:  Chlorine with less than 5 ppm moisture.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
Other Than Other Than Composition 1. Supplier loads rail car with incorrect material 1.1. Consequences will depend upon what other materials could be delivered in rail cars. 1.1.1. Analysis of shipment by supplier. 3 4 8  
 1.1.1. Consider changing the SOP to require a certificate of analysis be received with each rail car and be checked before accepting the rail car. DSC
As Well As As Well As Composition (contamination) 2. Rail car padded with incorrect material (e.g. moist air) by supplier 2.1. Moisture with chlorine will cause accelerated corrosion of system piping 2.1.1. Analysis of shipment by supplier. 3 4 8 :No further recommendations  
2.2. Consequences will depend upon what other materials could be delivered in rail cars 2.2.1. As for 2.1.1 3 4 8 :No further recommendations
 

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (1) Chlorine rail car
Drawings:  CLC/01-07-66
Parameter:  Level
Intention:  Normal railcar liquid level varies between a maximum of 80 % of capacity to as empty as practical.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
No No Level 1. Rail car received empty 1.1. Delay in treating 1.1.1. Rail car is weighed upon receipt 5 4 10  
 :No recommendations  
2. Leak in rail car or attached piping 2.1. Potential exposure of personnel and potential offsite impact 2.1.1. Chlorine gas sensors around rail car unloading station 3 4 8 :No recommendations
2.1.2. Emergency C kit available for rail car leaks
More Higher Level 3. Supplier overloads 3.1. Potential overpressure of rail car due to thermal expansion of material 3.1.1. Rail car weighed upon receipt 3 4 8 3.1.1. *Verify the scales are calibrated correctly LSS
 
 
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Worksheet

Page: 2
Company: Safetech
Facility: Princeton

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (2) Cl2 liquid to vaporizer
Drawings:  CLC/01-07-66
Parameter:  Flow
Intention:  Flow approximately 1 - 5 lbs/min of liquid chlorine, at 100- 150 psig, from the railcar to the vaporizer.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
No No Flow 1. Control valve CV-32 fails closed 1.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 1.1.1. Failing closed, or accidentally closing, a single valve will not result in overpressure since line is open to either end 4 4 9  
 :No recommendations  
1.1.2. Operator response to a shutdown of the system would be immediate
1.1.3. Limit switch provided on each valve which will indicate the valve is closed
1.1.4. Micromotion flow meter, FTLIQA
1.2. Potential overpressure of Cl2 piping if liquid-filled, closed piping heats up 1.2.1. All valves (ball valves) in liquid Cl2 service are provided with a port to vent the ball cavity 3 4 8 :No recommendations
1.2.2. Rupture disk discharging to expansion tanks are provided for the section of the piping between
- VLIQA and VLIQB
- PCVGASC and PCVGASB (downstream of vaporizer)
1.2.3. Pressure transmitters provided on potentially trapped sections of piping between:
- VRCA2 and VRCL
- VRCB2 and VRCM
- VRCL/M and VLIQA
- VLIQB and PCVGASC
2. Control system incorrectly activates shutdown for "rupture" condition 2.1. Potential overpressure of Cl2 piping if liquid filled, closed piping heats up 2.1.1. Rupture disk discharging to expansion tanks are provided for the section of the piping between
- VLIQA and VLIQB
- PCVGASC and PCVGASB (downstream of vaporizer)		 3 4 8 2.1.1. *Investigate the design of the rupture disks and expansion tanks and the pressure setting (375 psig) of the rupture disk LDS
2.1.2. Failing closed, or accidentally closing, a single valve will not result in overpressure since line is open to either end 2.1.2. *Verify Chlorine Institute requirements for venting valves with design of existing valves JBS
2.1.3. Limit switch provided on each valve which will indicate the valve is closed
2.1.4. Micromotion flow meter, FTLIQA
3. Control valve closes due to incorrect signal or setting 3.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 3.1.1. Failing closed, or accidentally closing, a single valve will not result in overpressure since line is open to either end 4 4 9 :No further recommendations  
3.1.2. Operator response to a shutdown of the system would be immediate
3.1.3. Limit switch provided on each valve which will indicate the valve is closed
3.1.4. Micromotion flow meter, FTLIQA
4. Manual block valve is accidentally closed 4.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 4.1.1. Failing closed, or accidentally closing, a single valve will not result in overpressure since line is open to either end 4 4 9 :No further recommendations
4.1.2. Operator response to a shutdown of the system would be immediate
4.1.3. Limit switch provided on each valve which will indicate the valve is closed
4.1.4. Micromotion flow meter, FTLIQA
5. Filter plugged 5.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 5.1.1. Operator response to a shut down of the system would be immediate 4 2 7 :No further recommendations
5.1.2. Micromotion flow meter, FTLIQA
6. Micromotion meter plugged 6.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 6.1.1. Operator response to a shut down of the system would be immediate 4 2 7 :No further recommendations
6.1.2. Pressure transmitters before and after the meter
7. Dip pipe (in railcar) plugged 7.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 7.1.1. Operator response to a shut down of the system would be immediate 4 2 7 :No further recommendations
7.1.2. Micromotion flow meter, FTLIQA
8. Excess flow valve closed 8.1. Interruption to production operation due to deviation of Cl2 flow from setpoint causing control system to shut down process 8.1.1. Failing closed, or accidentally closing, a single valve will not result in overpressure since line is open to either end 4 4 9 :No further recommendations
8.1.2. Operator response to a shutdown of the system would be immediate
8.1.3. Micromotion flow meter, FTLIQA
9. Line or flex hose failure 9.1. Release of Cl2 to the atmosphere 9.1.1. Railcars inspected between each load by supplier 1 4 4 9.1.1. Consider alternatives to the present hanger arrangements to allow total insulating of the piping while minimizing external corrosion of the piping. LDS
9.1.2. Chlorine gas sensors in the vicinity of the railcar and in the vaporizer building 9.1.2. Consider whether alternative materials of construction are practical which will provide better internal and external corrosion resistance TLK
9.1.3. Pressure along the piping is monitored by control system. If pressure differential exceeds 40-50 psig between 2 transmitters, control system will initiate a "line rupture" shutdown which closes all valves on the liquid Cl2 piping
9.1.4. Piping pressure tested prior to each campaign
9.1.5. Normal preventive maintenance program for Cl2 piping is to perform non-destructive testing of wall thickness annually
Less Less Flow 10. Block valve (VRCG/H, PCVLIQA) to vent scrubber system open or passing 10.1. Potential interruption to production if flow deviates significantly from setpoint 10.1.1. Second block valve, PCVLIQB, on vent line from railcar station would also have to be accidentally open or passing 4 4 9 :No further recommendations  
10.1.2. Position switches provided on all valves leading to the scrubber system from the liquid chlorine lines (VRCG, VRCH, PCVLIQA, PCVLIQB) which indicate if the valve moves off the fully closed position.
10.2. Potential release to the atmosphere if exceeds scrubber capacity or scrubber not operating 10.2.1. All the valves from the liquid chlorine lines to the scrubber (VRCG, VRCH, PCVLIQA, PCVLIQB) are interlocked closed by the control system when chlorine is in the system, preventing the operator from accidentally manually opening the valve from the console. 1 4 4 :No further recommendations
11. Partial pluggage of any component or partially closed valve 11.1. Potential interruption to production if flow deviates significantly from setpoint 11.1.1. Pressure transmitter, PTRCF, on vent line from railcar station would increase if upstream valve(s) passing and downstream closed 4 2 7 :No further recommendations
11.1.2. Temperature indication, TTLIQA, on vent line to flash pot may indicate lower temperature due flashing of Cl2 liquid
12. Leak 12.1. Release of Cl2 to the atmosphere 12.1.1. Chlorine sensor provided near atmospheric vent from scrubber system 1 4 4 12.1.1. Review the best available means for periodic testing and/or examination of the chlorine liquid piping system to ensure the system integrity PWP
12.1.2. Control valve on Cl2 gas flow to reactor, FCVGASA, will open to attempt to maintain set flow to reactor
More Flow 13. N2 pressurization valve, VRCC/VRCD, opens during padding of railcar, and manual block on tubing left open, displacing liquid Cl2 in line with N2 13.1. Potential erratic flow due to presence of N2 in system. Potential overchlorination of product due to surge of chlorine ahead of N2. Impact on product quality. Potential overloading of scrubber 13.1.1. Flow indication and control (FICGASA) on chlorine flow to reactor will throttle to maintain set flow 4 4 9 :No recommendations  
13.1.2. Position indicators on N2 valves (VRCC, VRCD) which indicates whenever the valve is off normally closed position.
14. Higher than normal pressure in rail car 14.1. Potential erratic flow due to presence of N2 in system. Potential overchlorination of product due surge of chlorine ahead of N2. Impact on product quality. Potential overloading of scrubber 14.1.1. Backup manual valve on N2 line is normally closed except when pressure testing the piping. 4 4 9 :No recommendations
14.1.2. Pressure monitoring of pipeline
15. Flow control valve, FCVGASA, opens wide due to incorrect signal or setting 15.1. Potential erratic flow due presence of N2 in system. Potential overchlorination of product due surge of chlorine ahead of N2. Impact on product quality. Potential overloading of scrubber 15.1.1. Independent flow indication, FTLIQA, to allow operator to verify flow control reading 4 4 9 :No recommendations
16. Sudden clearing of a blockage 16.1. Potential erratic flow due to presence of N2 in system. Potential overchlorination of product due surge of chlorine ahead of N2. Impact on product quality. Potential overloading of scrubber due to surge of chlorine 16.1.1. Flow indication and control (FICGASA) on chlorine flow to reactor will throttle to maintain set flow 4 2 7 :No recommendations
Reverse Reverse Flow 17. Blockage of the system downstream of the vaporizer 17.1. Vaporization of liquid in vaporizer will increase vaporizer pressure pushing liquid Cl2 back to rail car 17.1.1. Chlorine line is open back to the rail car preventing excessive pressure buildup 4 2 7 :No recommendations
17.1.2. Pressure indication on vaporizer outlet, PTGASA
17.2. No flow, sensed by FICGASA, will initiate a shutdown. Will close VLIQB and open VGASA to vent vaporizer to the scrubber 17.2.1. Flow indicators, FICGASA and FTLIQA, will indicate no flow 4 2 7 :No recommendations
17.2.2. Line upstream of VLIQB is open to the railcar
18. Rupture of the N2 pressurization line at the rail car when padding the rail car 18.1. Release of Cl2 to atmosphere 18.1.1. Piping downstream of vaporizer is vented to the scrubber thru VGASA 1 5 5 :No recommendations
18.1.2. Rupture disk and relief valve on vaporizer , discharging to catch pot T-22, if blockage is between vaporizer and VGASA. Additional capability to manually vent lines thru VGASC or PCVLIQA
19. Failure of liquid chlorine line or flex hose 19.1. Release of Cl2 to the atmosphere 19.1.1. Piping downstream of vaporizer is vented to the scrubber thru VGASA 1 5 5 :No recommendations
19.1.2. Rupture disk and relief valve on vaporizer , discharging to catch pot T-22, if blockage is between vaporizer and VGASA. Additional capability to manually vent lines thru VGASC or PCVLIQA
Other Than Other Than Flow 20. Failure of rupture disk on liquid line 20.1. Some flow of chlorine to the expansion tanks 20.1.1. Pressure indicator, PTLIQD, on line to expansion tanks 1 5 5 :No recommendations
20.2. Potential loss of expansion capacity if rupture disk released, expansion tanks filled and pressure rise in expansion tanks not observed by operator. 20.2.1. Chlorine gas sensors in the vicinity of the railcar and in the vaporizer building 4 5 10 :No recommendations
20.2.2. Pressure along the piping is monitored by control system. If pressure differential exceeds 40-50 psig between 2 transmitters, control system will initiate a "line rupture" shutdown which closes all valves on the liquid Cl2 piping
20.2.3. Piping pressure tested prior to each campaign
 

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (2) Cl2 liquid to vaporizer
Drawings:  CLC/01-07-66
Parameter:  Pressure
Intention:  Normal operating pressure is approximately 100-145 psig.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
More Higher Pressure 1. Fire exposure 1.1. Potential overpressurization of rail car resulting in release of chlorine. 1.1.1. Chlorine line insulated except at hangers 1 5 5  
 :No further recommendations  
1.1.2. Chlorine line open to railcar and/or vaporizer
1.1.3. Rail cars insulated
1.2. Potential rupture of the rail car if the rail car relief valve fails. 1.2.1. Rail cars provided with relief valve 1 5 5 :No further recommendations
1.2.2. Location of rail car minimizes likelihood of exposure
1.2.3. Pressure indicator, PI-1
2. Steam exposure 2.1. Potential overheating if broken steam line discharges on chlorine line 2.1.1. Chlorine line insulated except at hangers 3 4 8 :No recommendations
2.1.2. Chlorine line open to railcar and/or vaporizer
2.1.3. Rail cars insulated
3. High ambient temperature 3.1. Potential increase in pressure. Not likely to approach rated pressure of rail car 3.1.1. Chlorine line insulated except at hangers 5 1 5 :No further recommendations
3.1.2. Chlorine line open to railcar and/or vaporizer
3.1.3. Rail cars insulated
4. Change in ambient temperature after padding rail car 4.1. Potential for too low flow to the treatment system 4.1.1. Chlorine line insulated except at hangers 5 2 8 :No further recommendations
4.1.2. Chlorine line open to railcar and/or vaporizer
4.1.3. Pressure indicator, PI-1
4.1.4. Rail cars insulated
Less Lower Pressure 5. Leak in rail car or relief valve fails open 5.1. Potential exposure of personnel and potential offsite impact 5.1.1. Railcar emergency leak patch kit is available on site 1 5 5 :No further recommendations
5.1.2. Pressure indicator, PI-1
6. Empty rail car 6.1. Delay in treating 6.1.1. Rail car weighed upon receipt 4 4 9 :No further recommendations
7. Sudden change in ambient temperature 7.1. Potential for too low flow to the treatment system 7.1.1. Rail car weighed upon receipt 4 3 8 :No further recommendations
 

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (2) Cl2 liquid to vaporizer
Drawings:  CLC/01-07-66
Parameter:  Composition
Intention:  Chlorine to specification
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
As Well As As Well As Composition 1. Water, or other agents, in line after cleaning 1.1. Potential for accelerated corrosion of the piping 1.1.1. Normal procedure for cleaning includes blowing the system dry with N2 after cleaning 3 4 8  
 1.1.1. Consider means of cleaning the chlorine piping system which do not involve the use of water or incompatible materials LDS
1.1.2. Training of maintenance personnel working on chlorine system
2. Use of non- compatible materials, such as hydrocarbon- containing greases, during maintenance of system 2.1. Potential reaction possibly causing accelerated corrosion, fire or contaminants affecting product quality 2.1.1. Normal procedure for cleaning includes blowing the system dry with N2 after cleaning 3 4 8 2.1.1. Consider modifying the training program for maintenance personnel who may work on the chlorine system to include coverage of incompatible materials TLK
2.1.2. Training of maintenance personnel working on chlorine system
 
 
PHAWorks by Primatech Inc.

Worksheet

Page: 3
Company: Safetech
Facility: Princeton

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (3) Cl2 vaporizer
Drawings:  CLC/01-07-66
Parameter:  Flow
Intention:  Vaporize 100-150 pounds per hour. Target is 125.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
No No Flow 1. Exit valve is in off position 1.1. Overpressurization of vaporizer 1.1.1. Relief valves on vessel 3 4 8  
 1.1.1. *Verify relief valves undergo periodic testing LSS
2. Entrance valve is in off position 2.1. Product down time 2.1.1. None 4 4 9 :No further recommendations  
2.2. Excessive wear on pumps 2.2.1. Pumps have autoshutoff switches to prevent overheating 3 4 8 :No further recommendations
As Well As As Well As Flow 3. N2 purge stream valve is open 3.1. Impure product 3.1.1. Feed is tested when it is unloaded from rail car 4 4 9 3.1.1. Consider updating SOP to include a valve configuration flow sheet LSS
4. Impure Cl2 feed 4.1. Impure product 4.1.1. Feed is tested when it is unloaded from rail car 4 4 9 :No further recommendations  
4.2. Side reaction causing exotherm.  
 3 4 8 :No further recommendations
 

Table of contents
Session:  (1) 07/02/00
Revision:  0
Node:  (3) Cl2 vaporizer
Drawings:  CLC/01-07-66
Parameter:  Pressure
Intention:  Vaporizer is intended to operate at 3 atm.
GW DEVIATION CAUSES CONSEQUENCES SAFEGUARDS S L R REF# RECOMMENDATIONS BY
More Higher Pressure 1. Exit line from vaporizer plugged 1.1. Failure to provide adequate supply to reactor 1.1.1. Low flow alarm present 4 2 7  
 :No further recommendations  
1.2. Pressure build up in vaporizer 1.2.1. Pressure rating on vaporizer exceeds that of the supply tanks 4 2 7 :No further recommendations
2. Chlorine supply line has a greater flow rate than designed 2.1. Pressure build up in vaporizer 2.1.1. Pressure rating on vaporizer exceeds that of the supply tanks 3 4 8 :No further recommendations
Less Lower Pressure 3. Supply line plugged 3.1. Loss of productivity due to low chlorine supply to reactor 3.1.1. Low flow alarm present. 4 2 7 3.1.1. *Check to see if this has ever been a problem LSS
4. Rupture in line exiting the vaporizer 4.1. Release of chlorine to atmosphere 4.1.1. Chlorine gas sensors in the area 1 5 5 4.1.1. Consider installing an automatic chlorine source shutdown if the vaporizer pressure drops below 1.5 atm. JBS
4.2. Loss of reactant  
 4 5 10 :No further recommendations  
5. Leak in vaporizer 5.1. Release of Cl2 to atmosphere 5.1.1. Chlorine gas sensors in the area 1 5 5 5.1.1. Consider implementing a periodic check of vaporizer to ensure there are no pressure leaks LDS
 
 
PHAWorks by Primatech Inc.