28-02-2011, 10:02 AM
safe handling of chlorine.ppt (Size: 3.87 MB / Downloads: 245)
safe handling of chlorine
Production process
Raw material = Raw salt (Nacl) + Electricity
The salt is dissolved with water to form Brine.
Impurities are removed by chemical treatment, settling and filtration.
The purified Brine is pumped to electrolytic membrane cell Decomposing brine into chlorine, caustic soda and hydrogen.
Chlorine gas leaves the cell is cooled, dried, compressed and liquefied by using refrigeration machines, collect this liquid chlorine in CPV’s and transfer in to the storage vessels located in Bottling plant.
Filled in Tonners(900kg) and Cylinders(100kg,50kg).
Cell house reaction details
Stages of chlorine production process
Physical & Chemical properties of chlorine
Colour: Greenish yellow gas, Clear amber colour liquid
Odour: Irritating and pungent
Molecular symbol: Cl2
Molecular weight: 70.906
2.5 times heavier than air 1.5 times than H2O
Boiling point: -34.05 0 at 1 atmosphere pressure
Compressibility of liquid: 0.0118 % decrease of liquid volume per atmosphere increase of pressure
Solubility in water(25 0 C, 1 atm) : 6 Kg/m3
Maximum solubility at 9.40c : 1%
Freezing point : -100.980c at 1atm pressure.
Critical temp: 1440c.
Critical pressure :76.1atm.
Density of liquid chlorine :1.468g/cc at o0c.
Density of dry chlorine gas : 3.209g/litre at 00c and 1atm.
Specific volume of liquid chlorine : 0.6812cc/g at 00c and3.617atm.
Specific volume of dry chlorine gas : 311.7cc/g at 00c and 1 atm.
Viscosity of liquid chlorine : 0.0035g/cm-sec at 200c .
Latent heat of vaporization : 68.7g cal/g at (-34.50c).
Vapour pressure at 200c : 5.6atm.
Chlorine has great affinity towards Hydrogen, even at ambient temperatures. A mixture of chlorine and hydrogen comprising of more than 5% of either component can react with explosive violence, forming hydrogen chloride.
Chlorine reacts steadily with NaOH and lime to form hypochlorite.
Chlorine reacts rapidly with Ammonia.
Neither liquid nor gaseous chlorine is explosive or flammable
React steadily with many organic substances usually with the evolution of heat and in some cases resulting in explosion.
Below 1200c Iron, copper , steel , Lead, Nickel, Platinum $ Silver are resistant to dry chlorine
Platinum, silver & titanium are resistant to wet chlorine
Tantalum, PE & FRP are resistant to both wet and dry chlorine.
P.V.C and polypropylene are unsuitable for wet and dry chlorine in pressure line
Key uses and application
1. As disinfectant
• Owing to its strong oxidizing properties Chlorine is very effectively used to control bacteria and viruses in drinking water.
• A small residue of chlorine is left in the water to retain the necessary antiseptic or fungicidal properties.
2. Pharmaceuticals
3. Crop protection chemicals
4. Bleaching agent
5. Manufacturing of fuels, plastics, dyes, cosmetics, coatings, clothing, electronics, Construction materials, Automotive parts, Food materials, Cosmetics, Metals etc
Hazards associated with chlorine
Physiological effects of chlorine
Respiratory irritant.
It causes restlessness, throat irritation, sneezing and copious salivation.
Lung tissues may be affected, resulting in pulmonary edema.
The persons afflicted with asthma, bronchitis and other chronic lung conditions should not be employed in areas where chlorine is handled.
The threshold limit value of chlorine accepted at present is 2.9 mg/m3 of air.
Physiological effects of various concentrations of chlorine gas on human beings
Acute health effect
Liquid chlorine in contact with any part of the body will result in freeze burn.
Inhaling the gas causes coughing, tears and breathing difficulties
If person is trapped for a long period in high chlorine concentration atmosphere loss of consciousness and possibly death can result.
Symptoms are reversible if an exposed person quickly is removed from the contaminated area and given prompt medical attention.
Complete recovery is normal
Chronic human health effects=
No significant connection between chronic exposure to low concentrations of chlorine and adverse health effects.
No significant effects have been indicated for chlorine levels normally found in work places where chlorine is handled. Those levels typically are well below one ppm.