chlorineproductionprocess & safe hanling

8/13/2019 ChlorineProductionProcess & Safe Hanling

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AMA

I INTRODUCTION

•

Chloroalkali technology is one of the largest electrochemical industries inthe world. Main products being Caustic, Chlorine and Hydrogen is

generated by the electrolysis of Sodium Chloride, which is energy intensive.

Chloroalkali industries is the 2nd largest consumer of electricity next to

aluminum. Chloroalkali plants are notable for wide variety of hazards

inherent in their operation.

• These include:

• To hazards – chlorine is a notoriously toxic gas.

• Explosive hazards – Hydrogen forms explosive mixtures with Air or

Chlorine.• Corrosive hazards – These results from stray electric currents as well as

wet chlorine hypo chlorite and strong acids.

• Electrical hazards – High direct current are used in the electrolytic process

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AMA

I Chlorine is a very useful but Hazardous

Chemical

• Chlorine finds versatile application in our daily lifestarting from drinking water chlorination tosanitation, insecticides, pesticide, agriculture, drugs,pharmaceuticals, automobiles, paper, textiles, plasticand many more.

• Chlorine is a very useful & indispensable chemical.

•

Chlorine is also very hazardous & toxic because of itsproperties.

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I Properties of Chlorine

• Chlorine is a gas because its boiling points is -340 C which is lessthan ambient temperature. Due to low boiling point (-340 C) Itrapidly volatilizes when released from storage tanks and Tonnersto the atmosphere.

• Chlorine is liquefiable under pressure, because its criticaltemperature is1440 C

• Vapour Pressure of chlorine at 550 C: About 16 Bars (absolute)and increases to about 20 Bars (absolute) at 650 C.

• Toxic and Corrosive when water / moisture is present due toformation of Hypochlorous acid which further dissociates toHydrochloric acid and nascent oxygen.

• Yellow chlorine Hydrate (Cl2..8 H2O) may crystallize below 9.40 Cat atmospheric Pressure and therefore chlorine pipe lines maychoke in cold weather.

• Chlorine has ill effect on the human health.

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• Chlorine is very reactive gas, hardly found in free state.

• 0.15% is available in combined state only.

• Threshold value are as under – Odor threshold – 0.31 ppm

– PEL (OSHA) – 1 ppm

– TLV-STEL (ACGIH) – 3 ppm

– IDLH (NIOSH,MSHA) – 10 ppm

• Chlorine was used during world war 1 as a choking (pulmonary) agent. Recently in 2007 about 30tons chlorine was used in Iraq war.

• Extent of poisoning depends on amount of chlorine, how exposure take place and length of time.

• Exposure signs

Coughing

Chest tightness

burning sensation in hose, throat, eyes

watery eyes

blurred visionNausea & vomiting

Burning pain, redness, blisters on skin, frost bite in case of liquid chlorine.

Difficulty in breathing

Fluid in the lungs with 2-4 hrs.

HAZARDS ASSOCIATED WITH CHLORINE



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• Long terms effects are not found in people who survive sudden exposure.

• High potential for terrorist use, as readily available.

• Natural element extremely oxidizing.

• Combine with water forms hydrochlorous and hydrochloric acid and oxygen

free radicals. All cause major tissue damages.

• Possibility of public exposure during transportation and water treatment use.

• Corrosion due to leakage.

• Contamination with other liquid chlorine in storage can cause explosion.• Formation of NCl3 in liquid chlorine in storage can cause explosion.

• Chlorine toner valve leakage.

• Exposure of chlorine toner to high temperature or fire.

• Immediate reaction of dry chlorine with titanium.

•

Over chlorination is absorption and water chlorination.• Explosive with hydrogen in presence of moisture.

• Iron fire at 251 o C.

• Exothermic reaction with organic/oil/grease. • Cl2 gas liquefies in pipeline under external temp condition.

•

Liq Cl2 expands with rise in temp Also pressure rises with temp.

Contd…..



AMA

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Physiological effects of various concentrations of

Chlorine Gas on Human Beings.

S.no. Effects Chlorine

Concentration by

Volume (ppm)

(1) (2) (3)

i) Least amount required to produce slight symptoms after severalhours of exposure

1.0

ii) Least detectable odour 3.5

iii) Maximum amount that may be inhaled for 1 hour without serious

disturbances

4.0

iv) Noxiousness, impossible to breathe for several minutes 5.0

v) Least amount required to cause irritation of throat 15.1

vi) Least amount required to cause coughing 30.2

vii) Amount dangerous in 30 minutes to 1 hour 40 to 60

viii) Amount likely to be fatal after few deep breaths 1000.0

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• Release of chlorine is usually a flashing (two-phase) jet withsmall liquid aerosols drops embedded since when liquidchlorine is released, it flashes off more and more andsimultaneously expand to vapour creating a turbulence, whichcauses the remaining liquid to be broken up into an aerosols(small drops) and is carried along with the flashed vapour.

• The aerosol usually evaporates within a short period, leaving acold dense cloud of chlorine gas.

• Usually no significant liquid pool is formed under the Chlorinecontainer.

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Hazards Associated with Chlorine usage

(contd…)



AMA

I Hazards Associated with Chlorine usage

(contd…)

• A liquid pool may form if ambient temperatures are coldand/or the chlorine is semi refrigerated.

• For holes with diameters larger than a few mm, the contents

of a Tonner are released very fast and thus very less time isavailable for emergency response.

• Develops high hydraulic pressure in overfilled tonners oroverfilled bullets or in liquid full pipelines. This hydraulicpressure is sufficient to cause bursting of tonners or bullets or

pipelines with 1 to 3 degree C temperature rise.

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I Hazards Associated with Chlorine usage

(contd…)

• Chlorine reacts violently with substance such as oils, greases,paints, some solvents etc. it will also react with steel wool, oilfilings or pipe cuttings. It is, therefore, essential that foreign

material be removed from chlorine lines and containersbefore allowing chlorine to enter them.

• Wet chlorine gas may be handled in Titanium equipment.However, dry chlorine reacts violently with titanium.

• Dry Chlorine will react violently with hot steel. For this reason,

welding should only be done on Chlorine lines that have beenisolated, depressurized and made free from chlorine gas.Welding leads should not be attached to such lines.

Contd…..

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(contd…) • Dry chlorine does not react with steel at normal

temperatures. Under these conditions, steel is suitable forhandling and storing Cl2.

•

Chlorine and hydrogen mixture can react violently inequivalent mixture and the rate of reaction increase inpresence of oxygen. Ultra violet light can start this reaction.

• Methyl Chloroform and other organic solvents should not beused to clean equipment where large amounts of Chlorineand its residues are present.

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(contd…) • We must remember that Chlorine dissipates more rapidly on

a warm, windy day than on a cold, calm one.

• Causes inhalation health effects at relatively low

concentrations.

• Vapour pressure increases considerably with increase inTemperature.

• Liquid chlorine inside tonner and bullet expands more and

more with considerable increase in storage pressure with risein Temperature.

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Chlorine is also explosive with Hydrogen • Hydrogen is a Co- product in the manufacture of chlorine.

• Mixture of Hydrogen becomes explosive as per the properties

of mixtures of Hydrogen with chlorine, Hydrogen with air and

Hydrogen with oxygen as tabulated.

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The properties of mixtures of Hydrogen with chlorine, Hydrogen

with air and Hydrogen with oxygen

Properties of

Hydrogen/oxygen

mixture

Hydrogen/ Air Hydrogen /

Chlorine

Hydrogen /

Oxygen

Lower Flammability

Limit (LFL)

P=1 bar a, T=20. C

4.0% V/V 3.0% V/V 4.0% V/V

Lower detonation

Limit (LDL)

(atmospheric

condition)

18.2% V/V 17.5% V/V 9.0% V/V

Ignition (Auto

ignition) temperature

5600 C 2070 C

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Chlorine Production & Use in India

• Chlorine is a Co-Product in the manufacture of Caustic Soda.

• The production facilities are spread through out India.

8 Plants in East Zone, 15 Plants in West Zone, 4 Plants inNorth Zone & 9 Plants in South Zone.

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Chlorine Production & Use in India (contd…)

• In India, most of the total installed capacities of Caustic Soda/Chlorine are based on Membrane Cell Technology which isenvironmental friendly & energy efficient

•

No production is based on Diaphragm Cell Technology• Out of 19 Lakh MT of Chlorine Produced approximately 8.5

lakh MT Chlorine was captively used

• Approximately 10.5 lakh MT of Chlorine was transported frommanufactures to end users.

•

Chlorine is filled in small containers (900 kgs) & transportedthrough trucks.

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Chlorine Production & Use in India (contd…)

Sector wise use of Chlorine in India-

Vinyls (including PVC) - 18%

Organic Chemicals - 20%,

Inorganic Chemicals - 23%,

Pulp & Paper - 8%,

CPW - 11%,

Water Treatment - 2.0%,

Pesticides/ Insecticides/ Weedicides - 5%,

Pharmaceuticals - 0.53%,

Dye & Inks - 0.40%,Textiles - 0.60%,

Exports - 0.4%

Other Uses - 11%.

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I KEY TO ACCIDENT FREE PRODUCTION & HANDLING OF

CHLORINE

There is a potential danger during manufacture, storage, filling,transportation and use of chlorine (as discussed) and therefore necessarycontrol & safety measures needs to be adopted.

Key Factors

– Technical Up-gradation and Innovation. – Inclusion of all safety & control measures at the plant deignstage

– Following safe operating procedures, safe handling andtransport procedures.

– Training of operating personnel. – Training of Drivers and Transporters

– Learning from Past incidents

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I KEY TO ACCIDENT FREE PRODUCTION & HANDLING OF

CHLORINE

Compliacence to regulation, such as:

Gas cylinders Rule, 2004

Static & Mobile Pressure Vessels (Unfired) Rules, 1981

[SMPV (U) Rules, 1981]Factories Act, 1984

Manufacture, storage and import of hazardous chemicalRules, 1989.

The Chemical Accidents (Emergency Planning,

Preparedness and Response) Rules, 1996The Environment (Protection) Act, 1986

The Public Liability Insurance Act, 1991, amended in 1992

Central Motor Vehicles Rules 1989 (amended 95)

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I Caustic Soda/ Chlorine Production Process

(Common to all Technologies)

• Chlorine is a by product in the manufacture of caustic sodaTechnologies used for manufacture of caustic soda / chlorine

Mercury Cell Technology

Diaphragm Cell Technology

Membrane Cell Technology

• The Caustic Soda – Chlorine production & process can be subgrouped as:

brine treatment

Electrolysissodium hydroxide production, storage and handling

chlorine production, storage and handling

waste chlorine gas neutralization and production, storage andhandling of sodium hypochlorite

hydrogen production, storage and handling (chlorine filling)19



AMA

I Chlorine Manufacture process and the bullet

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1st stage

coolingfiltration

liquification

2nd stage

cooling

compressor

Drying

Storage

CL2 from

cell

90 0

Consumption

40 o H2SO4

3.0 Kgcm2

0 0 C

15 o C40 o C



AMA

I Control & Safety Measures in production of Chlorine

(Contd…)

Control & Safety Measures in Operation ofElectrolysers

– Hydrogen content in chlorine in the cell gas is monitoredto avoid formation of explosive mixture of Hydrogen &Chlorine.

– Electrolysers are shut off in case of high hydrogenconcentration in the cell gas of the electrolysers.

– In case of high chorine pressure on the electrolysers,control is provided to switch off and shut down.

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Control & Safety Measures in

production of Chlorine (Contd…)

Control & Safety Measures in Operation of Electrolysers(contd..)

In the event of emergency shut down, Chlorine isreleased to the chlorine absorption unit through

emergency relief valves. Emission of chlorine to theatmosphere is prevented.

Formation of combustible & explosive mixture ofhydrogen & chlorine in the operation of electrolysersare prevented by suitable Instrument contorl and safe

operation procedure. Air must be excluded from the hydrogen stream so that

it can not combine with hydrogen to form an explosivemixture of hydrogen and oxygen.

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Control & Safety Measures in production

of Chlorine (Contd…) Safety and control measures in Sodium HydroxideProduction, Storage & Handling

– All the caustic tanks are provided with in built facilities toprevent overflow or spillage of caustic soda. Such

facilities include containment and mitigation. – It should be noted that hydrogen gas can be released

into the vapour space above the liquid in storage tanks.Tanks are normally vented from the highest point.

– Testing for an explosive mixture of hydrogen in air

normally precedes any maintenance activity in the area. – Storage tanks may be lined to minimize iron

contamination of the prouduct and to avoid stresscorrosion cracking of the tank.

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COOLING AND DRYING

• The chlorine gas produced in the cell room is hot and saturated. The temp.

of the gas as high as 90 o c.

Aspects of safety are as under:• As titanium is used as a tube material for heat exchanger, a

careful review must be made to ensure, even in upset conditions

that dry chlorine does not come into contact with the tubes. Dry

chlorine reacts violently with titanium. Back flow preventor is

provided to take care this problem• Careful control with adequate failure warning, of the gas

temperature from the second coolers is required to prevent the

formation of solid chlorine hydrate (9.6 o C). The hydrate

formation may completely plug the heat exchanger or gas piping

creating a big hazard in cell room.

• Facilities for periodic or continuous washing of them demister must

be provided to prevent excess salt crystallization due to carryover

from the cell room. This can lead to high pressure drops and stoppage

of gas flow.

• To take care high temp of Cl2 before cooling the FRP line should be of

Alpolite (797) resin instead of Atlac 382 (Bis-phenol resin)



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The method used for chlorine drying is by contact with H2SO4. Dry Cl2 is

defined the moisture less than 150 ppm by volume of water.

• Aspects for safe operation

• Conc. Of H2SO4 is a major factor when selecting materials of construction.

Plastics or lined equipment and pipes must be considered.

• Outlet conc. to be maintained 78 – 80% by continuous dosing of 98% H2SO4

to ensure proper drying.• The use of H2So4 requires specific attention. Velocities must be kept low 1

m/sec to prevent excessive erosive wear. Due to corrosive nature of dilute

H2SO4 seals or rotating parts become rapidly worse.

• Flange guards to be provided on H2SO4 pipe lines to avoid splashing of H2SO4.

• Hot work permit to be issued on dilute H2SO4 after thoroughly washing/dryingthat system. H2 generates in dilute H2SO4 system during washing which can

lead to explosion with hot work.

• During above mentioned cooling & demisting operation, chlorinated water is

generated which is effectively utilized in vacuum De-chlorination system.

Contd….



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• Continuous monitoring of moisture in Cl2 by analysis/ by online

instrumentation is a must.

• Instrumentation to monitor acid flow conc., temperature, as well as

gas temp is required. The capabilities of monitoring the pressure

difference across the drying towers and cooling equipments is

important for detection of restriction to flow with in the system.

• Significant hazards involved in handling and storing H2SO4. All

personnel need to be adequately trained for every phase of drying

operation with particular attention given to avoidance of contact

with the H2SO4. Protective clothing & safety equipments should

be mandatory.

• Chlorine outlet from the drying tower should be at the top orimmediately in line with the top portion to avoid accumulation of

hydrogen at the top & to avoid explosion due to electrostatic

charge

Contd….



AMA

I Control & Safety Measure in production of

Chlorine (Contd…)

Control & Safety aspects in Chlorine Compression (contd…)

– Concentration of the H2SO4 in compressor to be monitored byanalysis on daily basis to avoid corrosion. Higher moisture content in

chlorine gas (due to inadequate drying) will corrode the chlorinecompressor

– Sulphuric acid mist is to be removed with glass wool candle filters toavoid chocking in liquefier & pipeline.

– Continuous PH monitoring of the chilled water of individual chlorinecompressor coolers are to be done to detect any tube leakage. If the

tube leakage of chlorine compressor cooler goes unnoticed, it willaffect the entire chilled water cycle.

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Chlorine (Contd…)

Control & Safety aspects in Chlorine Compression

– Automatic control valves and check valves are to be

provided to prevent the back flow of chlorine (in case ofcompressor tripping) in to the low pressure system.

– Chlorine Compressors are fitted with mechanical seal toprevent any leakage of CL2.

– Acid temp of the chlorine compressor is to be

maintained below 400 C to avoid corrosion.

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Chlorine (Contd…)

Control & Safety aspects in Chlorine Cooling, Drying&Liquification

– As titanium is used as a tube material for heatexchanger. Dry chlorine reacts violently with titanium.Back flow preventor is provided to prevent contact ofDry Chlorine with titaniunm.

Contd……

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Chlorine (Contd…)

Control & Safety aspects in Chlorine Cooling, Drying&Liquification

– Facilities for periodic or continuous washing of the demisters

provided to prevent excess salt crystallization due to carryoverfrom the cell room. This can lead to high pressure drops andstoppage of gas flow.

– To take care of high temp of Cl2 before cooling, the FRP linebetween electrolysers to chlorine cooler should be of properquality (Alpolite (797) resin instead of Atlac 382 (Bis-phenolresin)

– Hydrogen is continuously monitored in the sniff gas tomaintain below the explosive limit.

– Make sure that refrigerant used for liquefaction does notreact with Cl2 if there is a leak

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Control & Safety aspects in Chlorine Cooling, Drying&Liquification (Contd..)

– Under pressure safety seal is to be provided in the system.

– Alignment of the compressor & motor should be proper as vibration

damages seals and results gas/ acid leakage. – Provision to run the compressor with closed discharge valves in case

of startup/ stoppage/ maintenance (local by pass valve).

– Centrifugal compressor leads to unstable operation at high pressureand low volume. It can also occurs at low chlorine density. Thisresults surging. Speed control/ by pass control is required to ensure

stable operation. – Initiations for trips of the chlorine compressors are provide, In case

of abnormal chlorine temperature, chlorine pressure, oil pressuresshaft vibration & axial movements etc. since the chlorine is at thepeak pressure level at the compression stage.Contd…..

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Control & Safety Measure in

production of Chlorine (Contd…)



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The chlorine gas having moisture less than 150 ppm byvolume of water is considered to be dry chlorine.

Concentrated sulphuric (98%) has to be dosedcontinuously to ensure proper drying. Maintain outletconcentration (of chlorine drying Tower ) at 78% (Min)

The use of H2SO4 requires specific attention. Velocitiesmust be kept low at 1 m/sec to prevent excessive erosivewear. Due to corrosive nature of dilute H2SO4, seals orrotating parts rapidly deteriorates.

Contd..

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Production of Chlorine (Contd…)



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– Flange guards to be provided on H2SO4 pipe

lines to avoid splashing of H2SO4.( saturatedwith Chlorine)

– Hot work permit to be issued for maintenancework on dilute sulfuric acid containing vessels/pipe lines etc. since H2 generates in dilute

H2SO4 system can lead to explosion with hotwork. Such systems containing dilute sulfuricacid are to be washed & dried beforeundertaking maintenance work

– Re use the chlorine condensate generated inthe chlorine cooling. 33





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Control & Safety aspects in Chlorine Cooling, Drying

&Liquification (Contd..)

– The moisture content in Cl2 gas after drying has to be

detected by on line measurement Instrument/ or byAnalysis to ensure chlorine gas dryness since wet

chlorine is corrosive.

– Instrumentation to monitor acid flow, acid

concentration, acid temperature, for detection of

restriction of flow with in the drying system. – Chlorine outlet from the drying tower should be at the

top or immediately in line with the top portion to avoid

accumulation of hydrogen at the top to avoid explosion

due to electrostatic charge.

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I Control & Safety Measure in


Control & Safety Measures during Production ofLiquid Chlorine

– An important control parameter is moisture content in

dried chlorine in relation to the materials of constructionas wet chlorine is highly corrosive. The moisture contentis measured before liquefaction.

– Care needs to be taken about nitrogen trichloride (NCI3)as it is explosive. Procedures for maintaining levels of

NCI3 below the explosive limit is available. – In addition, care needs to be taken to avoid high

temperatures which could lead to a chlorine / ironreaction.

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I Safety & Control Measures in Chlorine Storage

and chlorine filling (contd…)

• Design aspects and Material of Construction of chlorinestorage Tanks.

– Liquid chlorine is generally stored in horizontal pressurevessels.

– Adequate distance between two storage tanks is to bemaintained.

– Chlorine storage tanks to be located away from hazardousprocesses or storage with potential fire/explosion risk tominimize risk of damage.

– Dyke wall and impervious flooring with 1:100 slope are tobe provided in the storage area.

– Tanks are to be designed as per IS 2825.

– Design pressure for chlorine storage tonner is 19.9 kg/ cm2at 650 C.

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and chlorine filling (contd…)

– Corrosion allowance of 3 mm is to be provided.

– 100% stress relieved and X-rayed.

– Material of Construction (MOC) of chlorine storage Tanks is

low temperature carbon steel SA 516 grade 60/70 (-350

Cto 550 C).

– Valves are of forged carbon steel, spindle of monel metalor SS 316 and bellows are of hastalloy C 276.

– Pressure Gauges with Haste alloy C diaphragm, Haste alloyC/ SS316 dip pipe.

– Bolts, nuts & studs of proper MOC is used. Stud- 320 L7_, (Nut – A194 grade -4)

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and chlorine filling (contd..)

• Control & Safety measures for storage of liquid

chlorine (contd…)

–

Provide Low and high level alarm, 20% low & 80% high. – Provide High & low pressure alarm, 2.5 Kg/ cm2 low and

11.5 Kg/ cm2.

– Provide Temperature alarm -150 C low and 300 C high.

– Provide Double Rupture disc, 13.5 Kg/ cm2. – Provide Double Safety valve which opens at 13.0 Kg /cm2 &

closes at 12.7 Kg/ cm2.

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• Control & Safety measures for storage of liquidchlorine (contd…) – Provide Double valve of international standards quality of

each line. – Provide Remote type valve in liquid chlorine line.

– Always one tank is to be kept empty for emergencytransfer of liquid chlorine.

– Connection of the emergency release line with the

neutralize system. – Provide adequate number of CI2 detector in the storage

area.

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• Control & Safety measures for storage of liquid chlorine(contd…)

– Transfer of liquid CI2 to empty tank. Time for transfer – 2hrs by compressed dry air at 10.8 Kg cm2. Tank volume –

100 NM3. – Foam is used to contain chlorine, leakage.

– Chilled water below 100C can be used to control liquid CI2spillage.

– Liquefied gas pool can also be controlled by covering witha large sheet of poly ethylene. Vapor evaporating frompool below the cover can be withdrawn by large bore hoseto a neutralization system with on line connected vacuumhose.

– Provision for Neutralization of chlorine with caustic soda (3

stage system). 40



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I Safety & Control Measures in Chlorine Storage and

chlorine filling (contd..)

– Prevent passage of liquid chlorine into drainage system/effluent.

– Dyke wall kept dry during rainy season.

– To avoid percolation, a steep slope is provided leading to a sumpwith provision of small pumps or airlifts for recovery.

– Provision for prevention of free access of wind and airflows topool area.

– The storage tanks may be fitted inside a close room with

emergency exhaust blower. Which is connected toneutralization system.

– Provide high capacity blowers in the storage and bottling areaconnected to the neutralizing system.

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SAFETY MESAURES FOR CHLORINE STORAGE TANKS

REQUIREMETNT UNDER SMPV – RULE 1981 – License under SMPV Rules must be obtained by the

producers.

–

Level or weight, pressure and temperature indicator will beprovided on each chlorine storage tank with proper alarmsystem.

– Provision for release of excess pressure with rupture discwill be provided at chlorine storage tanks.

–

It will be provided with safety valve and safety valve will beconnected to Hypo System. Pressure indication betweenrupture disc and safety valve will be given to detect anydamage in rupture disc. Alternately, two Nos. Safety ReliefValves to be provided on each storage tank.

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I SAFETY MESAURES FOR CHLORINE STORAGE

TANKS

REQUIREMETNT UNDER SMPV – RULE 1981

– Provision of emergency suction hose for evacuation ofchlorine leakage to hypo system will be provided.

– Provision of On – line Breathing Apparatus and Selfcontained Breathing Apparatus at different locations foremergency operation will be available at storage site.

– Dew point of padding air will be monitored. Dew pointshould not be more than -450 C

– Emergency Response Plan for Chlorine leakage is to bedeveloped as per statutory guide lines and to be madeoperational.

– The operation will be done by trained and experiencedpersons.

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Scrubbing of Waste Cl2

• For the scrubbing of waste vented chlorine, a scrubbing tower system

is used. Since in Cell gas is hot and wet and generally large volumeand at low pressure, a low pressure drop system is required.

• Two/Three scrubber are provided in series so that is capable of

absorbing all gases even during emergency. Bleach liquor in the

circulation is regularly checked for excess caustic to effect

changeover at proper time.

• Auto control valve is to be provided to maintain uniform vacuum in

the system

• Full Overhead tank with 20% caustic should be available to meet any

emergency it should be linked with ON/OFF control valves in order to

dump caustic from control room also.

• Temp alarm for sodium hypo system is required to maintain temp

below 35 o C

• Titanium pumps, MSRL pipeline & towers with titanium coolers are to

be used for the service to give reliable emergency services



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EMERGENCIES:

• The most common emergency is “Power failure”. To avoid

leakage of CL2 gas in the atmosphere, a number of critical

equipments are connected to the generator set with automatic

changeover.

•

Equipments generally connected with DG set are1) DC blower

2) Caustic circulation pumps

3) Emergency lights

4) Inst. Air, cooling water, chilled water & Nitrogen system

• Apart from this, regular inspection and changeover of

pipelines, hydraulic testing of storage tanks and containers are

done to minimize chance of any Cl2 leakage due to corrosion.



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INSTRUMENTATION

• Instrumentation plays a very important role in chlorine manufacture.

• some of this important instruments are as under:

• Rectifier Tripping Interlocks

• High Current of electrolyzer

• Tripping of 2 or more electrolyzer

• One of Cl2 compressor running

• High level of anolyte tank

• Low level of overhead pure brine tank

• High temp of catholyte vent pot

• High Cl2 pressure

• Low Cl2 pressure

• Low H2/Cl2 differential pressure

• High H2/Cl2 differential pressure

• Liquid Cl2 pumps not running

• Full opening of Hypo valves



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• In addition to this a multipoint chloro alarm sensors are provided

at various places within the complex to detect Cl2 leakage easilyat 3.00 ppm conc.

• These instruments are checked & calibrated regularly.

• Breathing apparatus and other emergency kits are available at

different locations.

ontd…



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MATERIAL OF CONSTRUCTION

• WET CHLORINE

LOW PRESSURE

1) Stone ware

2) Porcelain

3) hard rubber

4) Unplasticised PVC

5) Glass fiber (FRP)

HIGH PRESSURE

1) Titanium2) Tantalum inert up to 150 deg.c

3) Haste alloy „C‟

4) Monel metal „B‟

• DRY CHLORINE GAS OR LIQUID

1) Seamless carbon steel

2) Corrosion allowance 1 mm

3) Service temp –35 to 650c

4) Pressure- 19.9 kg/cm2

5) Tounge and groove flanges

6) Gaskets-CAF/Lead

7) Nut Bolts-Alloy Steel.



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Contd…..

• VALVES

1) Drop forged steel

2) Monel spindle/haste alloy „c‟

3) Cast steel seat

4) Teflon Gland packing.

Carbon steel is suitable upto 120 o C.

SS with 10% nickel is suitable upto 150 o C.

SS with more than 10% nickel is suitable upto 250 o C.

Monel is suitable upto 350 o C.

Nickel, Inconel & Hastalloy C is suitable upto 400-500 o C.

Nickel is used as lining material as it has poor mechanical properties.

PIPING DESIGN/MAINTENANCE



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• DESIGN:

Piping arrangements simple with min. flange joints/ screwed joints

Above ground layout

Well supported and adequately sloped

Expansion vessel in liqcl2(20% vol) Min 20 mm pipe diameter to be utilized

Lines cleanly labeled and painted as per color code (yellow)

Linseed oil and graphite,linseed oil and white lead ,litharge and glycerin can be used for permanent joint.

Seamless schedule 80 pipeline upto 6 inches above that schedule 40 is acceptable

Regular NDT testing of chlorine pipeline

Velocity to be maintained 2 m/sec

100% stress relieving & radiography for liquid Cl2 service pipeline

• MAINTENANCE:

All pipelines are to be cleaned.

No oil/grease/hydrocarbon/alcohol is to be used for cleaning

Cleaning can be done with trichlorethylene /carbontetrachloride

Chlorine line can be washed, steam heated and dried before use

Chlorine lines to be hydro tested before drying (Dry Air –400c Dew point)

After drying lines to be tested with

1)Dry Air-/nitrogen - check for leak with soap solution

3)Dry Air + chlorine - check leakage with Ammonia solution

4)chlorine - DO -

Never attempt to repair leak by welding until all chlorine has been purged.

The line to be retested after repair

Contact of Ammonia with Brass is to be avoided

All old & unused pipelines must be identified and removed.



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• Neutralization system by caustic soda to form sodium hypochlorite

products with emergency power supply (Three stage

neutralization)

• Use of safety kit to stop release.

• On line detection sensors for chlorine gas.

• All PPE‟s provided.

• Training of employees at shop floor and at consumers premises.

• Training of drivers and conductors.

• Rescue team availability on effected site on call.

• Provision of high capacity blowers in tanks and liquid Cl2 fillingarea (Connected with neutralizing system)

• Minimum inventory in liquid Cl2 tank

• Public announcement facility and local phones

SAFETY SYSTEMS



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Contd….

• Central Control Room for Co-ordination

• Earthing Systems.

• Remote control valve with local control

• Double valve in each line

• Emergency release line

• Seamless piping with tongue and groves flanges.

• Expansion chamber in liquid CL2 line.

• 100% instrumentation control in CL2 system manufacture

• Competent persons to handle liquid Cl2 system approved by CCE

• Liquid Cl2 tank insulated with 75 MM thick thermocole insulation

and cladded with Aluminum sheet

• Flame proof lights



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•Adequate wind socks are provided to know wind direction.

• Tank replacement every 20-25 years irrespective of tank

health/condition or after the report by third party or in case

of physical damages.

• Assembly points identified and marked properly for

emergency.

• Periodical mock drill exercise carried out.

• Availability of On site/Off site emergency plan

Other Safety Measures in complex



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STATUATORY REQUIREMENT

1. License for liquid Cl2 storage in tanks.

2. License for liquid Cl2 storage in Tonners/Cylinders.3. Approved layout plan indicating surrounding area and Cl2 neutralizing facilities.

4. Liquid Cl2 filling license.

5. Recognition for hydraulic testing facilities of Cl2 Tonners/cylinders

6. List of competent persons handling Cl2 operation

7. Environment protection Act.8. The Factories Act

9. ON site/ OFF site emergencies Plan.

10. Mock drill (every Six month)

11. Hydraulic testing of Tonners/storage tank every two year.

12. Compliance of GAS CYLINDER RULES 2004 and STATIC AND MOBILE VESSELRULES.

13. Lloyd inspection report of every Tonner and CCE approval before filling.

14. SAFETY MANUAL with MSDS and safety permit system.

15. Central Motor Vehicle Transport Act.

16. Storage and impact of Hazardous chemicals Rules.

17. The Public liabilities Insurance Act.



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Equipment for chlorine handling

TonnersNet carrying capacity -900 Kg. It is a welded steel tank with agross wt of 1500 Kg.

Manufactured as per ASME SEC VIII DIV.1:2004.

The provisions made under

1) Gas cylinder rules,1981, 2004 and

2) IS:4263-1967(code of safety for Chlorine).

To be followed while handling these tonners and cylinders.

Any party possessing more than 5 containers at any one time willhave to take out a license under the gas cylinder rules; 1981,2004.



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I Chlorine tonner



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Various safety measures related to chlorine tonner

design and usage

1. Concave ends.

2. Hydrostatic stretch testing.

3. Rejection when permanent stretch is more than 10%.4. Rejection when tonner weight loss exceeds 5%.

5. Approx min.10% empty space after filling.

6. Filling and emptying on weighing balance.

7. Periodic checking of weighing balance calibration.



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8. Regular inspection for dents, pitting and any abnormal

loss in weight after every trip.

9. Valve protection hood .

10. 24 hours storage after filling for observation.

11. 900kg liquid chlorine filling in the tonner

quantity of liquid chlorine (kgs)= water capacity*1.19



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Cylinders Cylindrical container of welded steel construction with one end

closed and a valve at the other end. A valve protective hood is

fitted on the threaded neck ring.Capacity 100 kg and 50 kg.

Made as per IS:7681, IS:3196-Part-4:CL-1 1958



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I Chlorine cylinders

A i f t



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Accessories of tonner• 2 nos of valves as per IS: 3224

• 2 nos of Brass plug for inspection

•Two number of 15 NB eduction pipe

• 1 no of valve protecting dom (hood)

Our Container valve specification

Type 1, size 2, 3/4 14NGT (cl)-2 with outlet No.5 as per IS3224:2002.

Type1 - Stem taper indication.

Size2 - Total dimension indication.

¾ 14 NGT - Thread specification.

NGT threads are based on the American standard taper pipe

threads but are longer to provide fresh threads if furthertightening is necessary.

IS:3224:2002 is the Indian standard valve fittings for compressedgas cylinder excluding liquefied petroleum gas cylinders (L PG).

Chlorine cylinder valve



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Eduction pipe



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Material of construction of valve Body---Aluminium Silicon Bronze alloy.

Spindle---Monel (Nickel copper alloy).

Gland nut, Neck ring---Brass.

Gland packing---PTFE. Valve suppliers

Kosan industries Pvt Ltd Surat

Techno valves Kolkata.

Vanaz engineers Ltd Pune



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CONCLUSION

• BREADTH AND DEPTH OF DEFENCE FOR CHLORINE SAFETY

• PREDICTION

• PREVENTION

• DETECTION

• MANAGEMENT

• AUDITNG

• IMPROVEMENT

• Refresher training to operating personnel

• Thinking globally and working locally



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Recommended standard procedure for

handling chlorine containers

1. The process area should be well ventilated with frequent airchanges so as to minimize the impact of any sudden leakage.

2. Carry out all operation under the supervision of a trainedand competent person

3. Under the provision of the gas rule 1981 any personpossessing storing or using 5 containers or more at a time

has to obtain an appropriate license from chief controller ofexplosives, Nagpur (PESO).



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4 Care should be taken that the surface over which containeris moved is as smooth as possible and does not involve

sudden drops and lumplings.

5 Particular care has to be taken to ensure that the valvehoods are in place while the containers are moved.

6 Ammonia torch should be located at near by places where

chlorine containers are generally received stored or usedin process, so as to facilitates easy detection of any leakage.

7 In case of any leakage from the containers immediate andappropriate action is to be taken only to control the leakafter controlling the leak the supplier should be

immediately informed to take suitable action.



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8 Consumer should not make any effort to repair

affected portion of the container.

9 Gas masks and emergency kits should be located in

secured cabinets at strategic points. These are to beperiodically inspected to ensure that they are properly

maintained and in working condition.



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10 All chlorine consumer must establish and maintain

appropriate facility for chlorine absorption through caustic

soda/ lime/ soda ash/ solution to be of use in the event of

major leakages

11 Valve hood should be removed from the container only

during the time it remains connected to process. Care shouldbe taken to ensure that the valve hood remain fitted to the

container at all other times.

12 Even the slightest leak should not be neglected. A chlorine

leak never get corrected by itself it can only get worse



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13 water should never be used directly on the container forcontrolling the leakage.

14 As chlorine is heavier than air it tends to accumulate near the

ground. In case of any leakage it is advisable to move all

personal to higher areas opposite to the windward side.15 Tonners storage should be in cool, dry covered space and

protected from direct sunlight / weather and extreme

temperature changes. Proper handling facilities should also

be provided.

Despatch of empties



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I Despatch of empties• Abnormalities or defects, if any are noticed may be

specifically pointed out in the dispatch Chelan.• Containers may be loaded on to the truck with the help of a

hoist or wooden ramp ensure that valve cap nuts are fullytightened and the hoods fixed in position.

• Containers should be properly secured with ropes, wooden

blocks etc, and should not project outside the truck frame,also ensure that the valves of tonners are in vertical plane.

• Dispatch new cylinders for filling only with proper attestedcertificates such as Cylinder manufacturing certificate withannexure1, annexure2, annexure3, valve certificate and fillingpermission from PESO with a covering letter from concernedofficer.

Emergencies and emergency



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I Emergencies and emergency

management• There are many hazards inherent in the manufacture, storage,

handling and use of chlorine. Whenever chlorine is handled, a

potential risk is involved and a serious emergency may

suddenly crop up.

• The most common kind of emergency that arises duringchlorine handling by consumer is through leakage and rarely is

due to fire.

• A chlorine leak never gets corrects by it self. It only gets worse

if not promptly attended to.• Water should never be used on a chlorine leak.



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Measures in facing leakages

• Detect the exact location with the help of an ammonia torch

• Remove all the persons, not directly concerned from the areaaffected.

• If the leak is from process cut off the supply.

• If the leak is from the valve roll the cylinder make the leakingvalve on top.

• Ensure that only chlorine gas escapes instead of liquid. Onevolume of liquid chlorine is equivalent to 457.6 volume ofgaseous chlorine.



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Type of valve leak and remedies

•Leak from valve

packing

•Leak from valve seat or

from spindle•Leak due to defective inlet

thread

•Broken valve

•Tighten the gland nut

•Gently open and close the

valve•Tighten the valve carefully

to the container

•Use the valve hood

assembly



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Tonner shell leakage

• Bring the leaking point on top by rolling the tonner.

• Insert a led peg or soft wooden wedge with a hammer inside

the leaking hole.

• Use chain and yoke assembly made to arrest tonner/ cylinderwall leak.

• If leakage continues chlorine may be absorbed in caustic soda

solution, hydrated lime solution or soda ash solution

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I Chlorine emergency kit

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I Leak arresting by using emergency kit

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The effect of chlorine exposure on eyes

• Irritation associated with burning discomfort spasmodic

blinking, redness, conjunctivitis and burning.

Do’s

• Hold the eyes open, flush with tepid water.• Get medical attention.

Don’ts

• Do not try to neutralize with chemicals.

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The effect of chlorine exposure on skin

• Burning sensation and skin irritation typically at high

concentration.

Do’s

•

Flush with tepid water for 15 minutes.Don'ts

• Do not apply any ointment for 24 hrs as it may lead to

irritation

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The effect of chlorine inhalation

• Exposure to low concentration may cause nasal and respiratorytract irritation.

• At higher concentration coughing and difficult breathing

possibly leading to respiratory distress.

• Any chlorine inhalation in an individual with compromisedpulmonary function should be regarded as a severe inhalationand a respiratory emergency.

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Do’s

h d f h d



I • Remove the exposed person to fresh air and summon

professional medical assistance immediately. If breathing has

ceased, begin artificial respiration. Trained personnel should

administer oxygen as soon as possible.

• If breathing has not ceased the person should be placed in a

comfortable position either seated in a chair or in severe case

laying down with the head and body trunk elevated at 450 to

600 angle. Encourage the person to take slow deep regularbreath. Administer oxygen as soon as possible. Keep the person

warm and at rest.

Don'ts

• Sodium bicarbonate should not be given.

• No attempts should be made to induce vomiting or to use a

stomach tube.

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The effect of chlorine ingestion

No adverse effects are anticipated by this route of exposure.Do’s

If a person is swallowed chlorine and is conscious he should be

made to drink copious amount of lime water, milk of

magnesia, curd or fresh water. The victim may be expected tovomit spontaneously. Get medical attention immediately

Don’ts

Alcoholic drinks shouldn’t be given.

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I Personal protective equipment

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• Self contained breathing apparatus

• Emergency escape breathing apparatus

• Industrial canister type mask

• Helmet

• Hand gloves

•

Face shield• Protective clothing

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References for safe operation •



I • INDIAN EXPLOSIVE ACT 1884

• Gas Cylinder Rules 2004

• IS 8867 - Hydraulic Stretch Test – test pressure

• IS 3710 - Values of saturated VP of different gases.(FILLING RATIO)

• IS 3224 - Specifications of Industrial gas cylinders.

• IS 5903 - Details of safety devices in cylinder valves fittedwith safety devices.

• IS 4379 - Identification colours for industrial gases.

• IS 356 - (IS Standard Colour No. 356) Colour of gas Non-flammable but toxic.

• IS 5844 - Hydrostatic stretch test – Procedure (welded

cylinder)• IS 3196 - Specification of low pressure liquefiable gas

service.

• ASME - Specification of Cl2 tonners

(SEC. VIII WITH LATEST AMENDMENT CHIMED

ENDS SPECIFICATION NO. 179.300 OF CFR 49)

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I •



I Static Mobile Pressure Vessel Rules 2004

• IS 2825 - Design code of pressure vessels.

• IS 4263-1967 - Code of safety for chlorine

• IS 10553 - Withdrawal of Cl2 from ton container.PART:I, 1983 - (Requirements of chlorinationequipments, general Guidelines for chlorination plant andsafety of chlorine.

• IS 2379-1963 - Colour code for identification for

pipelines.• IS 10553 Part(2) – Vacuum feed type chlorination.

• IS 10553 Part(4) – Gravity feed gaseous chlorination.

• IS 646 - Chlorine purity.

•

USA Chlorine Institute pamphlets.• Eurochloro guidelines.

• World Chlorine Council guidelines

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I Conclusion



I Conclusion

• Safety is the result of conscious, well-thought

out, painstaking and sustained actions by the

Entire Team involved.

• Brilliant but erratic actions cannot ensureSafety.

• Safety is inescapably linked to Total Quality

Management ..

chlorineproductionprocess & safe hanling

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