SUGGESTED MAINTENANCE OF CHLORINE EQUIPMENT
PRESSURE CHLORINATOR – AQUEOUS SOLUTION FEED TYPE
S.No | Name of item | Period | Action needed |
1. | Chlorine Leakage | Daily | Inspected & take necessary action |
2. | Pebbles in tower | 15 days | Clean with water |
3. | Calcium chloride | 1 month or earlier if shape is changes | Replace |
4. | Orifice | 1 Month | Clean with trichloroethene |
5. | Stop valve & regulating valve | 3 Months | Clean with trichloroethene |
6. | Diaphragm | 3 Months | Clean with trichloroethene |
7. | Manometer | 3 Months | Clean with trichloroethene |
9. | Gasket | 3 Months | Calibrate |
10. | Sleeves | 3 Months | Replace |
11. | Filter | 3 Months | Clean or replace |
12. | Pressure gauge | 3 Months | Inspect & calibrate if necessary |
13. | Injector | 3 Months | Clean with matter |
14. | Tube | 6 Months | Replace |
15. | Nut bolt | 12 Months | Replace |
16. | Sulphuric acid | 12 Months | Replace |
17. | Rubber hose | 12 Months | Replace |
SUGGESTED MAINTENANCE OF CHLORINE EQUIPMENT PRESSURE CHLORINATOR – AQUEOUS SOLUTION FEED TYPE
S. No | Name of item | Period | Action needed |
1. | Chlorine leakage through fittings etc. | Daily | Inspect and take necessary action |
2. | Chlorine leak detector & Exhaust fans | Daily | Inspect and take necessary action |
3. | Safety equipment & Breathing apparatus | Weekly | Inspect and take necessary action |
4. | Chlorine neutralization system | Weekly | Inspect and take necessary action |
5. | Water pump | 3 Months | Inspect and take necessary action |
6. | Chlorine gas filter | 6 Months | Replace filter element |
7. | Sedimentation trap | 6 Months | Clean |
8. | Rota meter tube & metering orifice | 6 Months | Clean |
9. | Wind cock | 6 Months | Replace |
10. | Gas header of valves | 1 year | Replace |
11. | Stem & seal of valves | 1 year | Clean |
12. | Injector throat | 1 year | Clean with mild HCL & then with water |
13. | Lifting tackle/crane | 1 year | Inspect and take necessary action |
14. | Copper tubing between header & cylinder | 1 year or screeching sound is heard on bending | Replace |
15. | Header System | After every 250 Tons passing of chlorine | Clean with water & dry it |
16. | Springs in the valves | 2 years | Replace |
17. | Pressure gauges & pressure switches | 5 years | Replace |
18. | Diagram in spring loaded value | 5 years | Replace |
19. | Joints | Whenever opened | Replace gasket with new one. Wire brush the thread & use Teflon tape for lubricant |
20. | Evaporator vessel | 250 tons of chlorine passage | Clean |
S. No. | Description | Pressure Type Chlorinator | Vacuum Type Chlorinator | |||
Dry feed | Aqueous solution feedsolution feed | |||||
Gravity feed | Injector Solutioniser | With Differential vacuum regulator | Sonic flow type | |||
1. | Rate of feed (max) | 230 kg/d | 230kg/d | 230kg/d | 4800kg/d | 240 kg/d |
2. | Water requirement per kg of chlorine (min) | Nil | 1500 lit | Less than 1500 lit. but more than 300 lit. | 300 lit. | 300 lit |
3. | Accuracy | Low. | Low. | Low | High | High |
4. | Flow meter | Manometer | Manometer | Manometer | Rotameter | Rotameter |
5. | Pressure at point of application | 0.7 kg/cm2 (max) | 0.7 kg/cm2 (max) | More than 0.7 kg/cm2 | More than 0.7 kg/cm2 | More than 0.7 kg/cm2 |
6. | Energy requirement Low | Low | Low | Moderate | Moderate | High |
7. | Maintenance | Extensive | Extensive | Extensive | Moderate | Less |
8. | Status | Not in | Not in | Not in | In production | In production |
9. | Remarks | Not suitable below 10degrees C water. It is used when quality of making solution is not good. It is less safe. | Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree centigrade. It is used when quality of water for making solution is good. It is less safe | Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree Centigrade it is used when quality of water for making solution is good. It is more safe | Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree centigrade. It is used when quality of water for making solution is good. It is less safe | Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree centigrade. It is used when quality of water for making solution is good. It is less safe |
IMPORTANT FACTS ABOUT CHLORINE FROM SAFETY POINT OF VIEW
Sl No | Facts | Reasons | Remedy |
1. |
Chlorine is supplied in liquid form under pressure & it requires heat for converting |
It occupies less space |
Proper ventilation and proper handling |
2. |
It is not poisonous but irritant |
If forms corrosive acid with body moisture and hence inhalation can cause respiratory injury raging from irritation to death depending upon its inhalation. |
Use breathing apparatus. |
3. |
Dry gas is not corrosive but wet gas is highly corrosive |
It forms acid with water |
Do not use water on leaking container. |
4. |
It is neither flammable nor explosive but supports combustion of carbon steel at 251oC. |
Containers are made up of carbon steel. |
Do not carry out welding work on chlorine containers or piping unless purged out. |
5. |
Gas combines with ammonia & Forms white smoke, |
White smoke detects chlorine leak. |
Use for chlorine leakage through the system |
6. |
Liquid chlorine has large coefficient of expansion. |
If the container is filled with filling of 1:19 complete container will be occupied by liquid chlorine at 84o C and hydrostatic rupture may take place. |
Do not place the container near the fire or source of heat. |
7. |
Vapour pressure increases with temperature rise. |
Container may rupture due to rise in pressure |
Do not place the container near the fire or source heat. |
8. |
Gas is 2.5 times heavier than air. |
Leaked chlorine settles at the ground level |
Install exhaust fans at ground level & information the public to take higher level during chlorine leakages. |
9. |
It is slightly soluble in water but it gets absorbed in caustic soda, soda ash and hydrated lime. |
During reaction with caustic soda. Soda ash & hydrated lime heat evolved. |
Use soda ash, caustic soda or hydrated lime for neutralization of chlorine. Do not use water for neutralization purpose. Do not push container into solution |
10 |
Liquid leaks 15 times more than the gas. |
It is because of viscosity difference well as different laws of gas and liquid. |
Turn the leaking container such as to allow leakage in gaseous form. |
11. |
Chlorine forms hydrate with water at temperature below 9.4O C |
Solid layer is formed |
In the case of liquid leak if chilled water is sprayed on the top a solid layer formation will reduce the rate of evaporation of chlorine. |
12. |
It is dangerous with ammonia gas. Hydrogen, turpentine and hydrocarbon as reactions with these are explosive; powdered metal may cause fire in chlorine |
Fire may start in storage of chlorine |
Avoid storage of these materials in the chlorine storage. Do not lubricate the valves. |
MATERIALS OF CHLORINE EQUIPMENT & ANCILLARIES
S.No. | Equpipment | Material |
1. | Piping Rigid | Seamless carbon steel ASTM A 106 grade ‘B’ schedule 80 or equivalent BIS- 1030-1974 |
2. | For gas below atmospheric pressure | Rigid uPVC (for under shed), polyethylene tube, HDPE (outside shed). |
3. | Globe valves | Body : Forged carbon steel Trim : monel or hastelloy ‘C’ Stuffing box : PTFE or graphite packing. |
4. | Ball valves | Body & end piece: Forged carbon steel, ASTM A 105 or equivalent IS Seat : PTFE Ball : Monel |
5. | Springs | Tantalum alloy. Hastelloy |
6. | Gasket | Lead containing 2 to 4% antimony or bonded asbestos. |
7. | Chlorimator | Vacuum Regulator body : Carbon Steel Regulator diaphragm : FLUON, FEP, Cabinet: FRP ‘O’ ring & gaskets : Fluorocarbon lead oxide (litharge cured) viton |
8. | Pressure gauge | Diaphragm: silver, tantalum, hastelloy, monel alloy Liquid: fluorocarbon, (silicon oil) fluorolube ‘MO’10 |
9. | Differential Regulator | Body : U pVC , ABS , ebonite, PVDF |
10. | Pressure relief valve | Body: uPVC, ABS, ebonite, PVDF Stem: Ag, hastelloy, monel |
11. | Injector | Block: ebonite or PVC, ABS |
12. | Evaporator | Vessel: boiler quality steel |
13. | Rupture disc | Silver : monel, tantalum, hastelloy, “C” |
14. | Rotameter | Glass : borosilicate Float : PTFE, tatalum, hastelloy, glass |
15. | Filter media | Glass wool |
16. | Diffuser & solution line | Rigid UPVC saran or rubber lined steel, HDPE, uatural rubber , hose. |
17. | Pressure reducting valve | Body: Ductile cast iron Diaphragm: FPM (Viton), ECTFE/FEP Plugs: silver or tantalum, hastelloy Seats: PTFE |
18. | Check valve springs | Tantalloy/hastelloy |
19. | Non permanent joints | Mixture of linseed oil and white lead or mixture of linseed oil and graphite or Teflon tape. |
20. | Permanent Joints | Glycerine & litharge |
21. | Screws | Monel & stainless steel. |
TROUBLE SHOOTING CHART FOR VACUUM TYPE CHLORINATOR
Trouble | Cause | Remedy |
1. Required gas follow not achieved at start up. | a. Insufficient ejector vacuum caused by insufficient water supply by pressure or excessive back pressure. b. Leakage at vacuum line connection at outlet from flow meter, rate control valve, differential from flow meter differential pressure regulator, and/or inlet to ejector. c. vaccum lines (s) flexible crimped. |
a. Refer to Trouble at S.No.6 b. Inspect each connections and remake if necessary c. Replace vacuum tubing and arrange line (s) to eliminate crimping. |
2. Required gas flow rate is not achieved on startup following an extended period of shutdown. | a. Insufficient ejector vacuum. b. Leakage at vacuum line connection at outlet of flow meter, rate control valve, differential pressure regulator or inlet to ejector. c. vacuum line (s), if flexible, crimped. |
a. Refer to Trouble at S.no. 6 b. Inspect each connection and remake if necessary. c. Replace vacuum tubing and arrange line(s) to eliminate crimping. |
3. Flow meter float observed bouncing and/or maximum gas flow cannot be achieved during normal operations. | a. Gas inlet filter of vacuum regulator dirty. b. Rate valve dirty. c. Flow meter dirty. d. Ejector water supply pressure fluctuating too wide (float bounce) or insufficient ejector vacuum |
a. Replace gas inlet filter assembly. b. Clean rate valve. c. Clean flow meter d. Correct water supply pressure as necessary. |
4. Flow meter fails to indicate gas flow during normal operation but there is no out –of-gas indication | a. Rate valve plugged b. Gas flow meter plugged c. vacuum lines, if flexible, crimped. |
a. Clean rate valve. b. Clean gas flowmeter. c. Replace vacuum tubing and re-arrange lines to eliminate crimping. |
5. No gas indication during normal operation | a. gas valve(s) closed. b. Gas supply exhausted. c. Clogging of filter in vacuum regulator. |
a. Open gas supply valves. b. Replenish gas supply. c. Replace filter. |
6. Insufficient ejector vacuum | a. Y-strainer in water supply line is dirty reducing available supply pressure b. Back pressure is greater than value listed for one of the following reasons; i) solution valve, if present, not fully open. ii) Solution line, present , partially blocked. iii) back pressure at point of application has increased above its original valve. c. Ejector nozzle and/or throat dirty. |
a. Clean Y-strainer. b. Open solution valve, clean solution line. |
7. Loss of gas feed | a. Dirty or plugged ejector nozzle. b. Insufficient water pressure to operate ejector. c. No gas supply. |
a. Check for vacuum in ejector clean nozzle. b. Provide proper water pressure c. Replenish gas supply. |
8. Flooded feeder | Dirt lodged on the ejector check valve seat | Clean or replace seat or o-ring. |
STANDARDS RELATED TO CHLORINATORS
BS:1500::For tonners
IS:7681::Specification for welded low carbon steel gas cylinders for chlorine gas.
IS:3224::Specification for valve fittings for compressed gas cylinders.
IS:4263::Code of practice for chlorine
IS:10553::Parts I & II: Requirements for chlorination equipment
IS:5844::Recommendations for hydrostatic stretch testing of compressed gas cylinders.
IS:4379::Identification of contents of industrial gas cylinders.
IS:646::Specification for liquid chlorine
IS:8198 part 6::Code of practice for steel cylinders for liquified chlorine gas
IS:5845::Code of practice for visual inspection of low pressure welded steel gas cylinders in use.
IS:8868::Periodical inspection interval of gas cylinders in use
IS:9200::Methods of disposal of unserviceable compressed gas cylinders
IS:5903::Recommendation for safety devices for gas cylinders
IS:3710::Filling ratios for low pressure liquifiable gases contained in cylinders.
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