Some interesting terms of water
1. Degree of hardness :- The degree of hardness of water states that the presence of equivalent amount of Caco3
Besides this hardness of water is never present in the form of calcium carbonates because it is insoluble in water and also hardness is actually caused by bicarbonates, chlorides ,and sulphates of calcium and magnessium
Calcium carbonate is used as the standard reporting of hardness of water is due to following reasons
1. The very first reason is that its molecular weight is exactly 100 and its equivalent weight is 50 so ,it makes calculation easy.
2. An another reason for using calcium carbonates is that it is most insoluble salt ,that it can be pricipitated in water treatment process
Formula used for the calculation is
=[weight of hardness producing substances in mg/L]*[100]÷[chemical equivalent of hardness causing substances]*2
MF (multiplication factor) = molar weight of CaCO3/2*chemical equivalent of hardness causing substances
2. Breake point chlorination or free residual chlorination :- chlorination is done for the the treatment of water for not only to treat the living organisms of water but also to destroy the organic inpurities this process is known as break point chlorination
While chlorine is added into water it is used for different reaction such as oxidation of reducing substances present ,chlorination of any organic substance and also free ammonia living behind mainly free chlorine which possess disinfection action against paythogenic bacteria it is also known as free residual chlorination
A typical relationship between the amount of chlorine added to water and the free residual chlorine (experimently determined).
The addition of chlorine at break point is known as break point at which free residual chlorine begins to appear normally all tastes odors disappears at break point.
Caustic embrittlement :- During this phinomina the boiller material becomes brittle due to the accumulation of caustic substance
It is a form of corrosion caused by high concentration of sodium hydroxide in boiler water
It is most likely to occur in boillers operating at high pressure where NaOH is produced in the boiler by hydrolysis of some residual Na2CO3o obtained from water softening process like lime soda
Na2CO3 + H2O -----------> 2NaOH + CO2
The formation of NaOH makes the boiler water caustic this caustic water penitrates into the minute hair cracks present in the inner side of boiller by capillary action
When the water evaporates and the concentration of dissolve NaOH increases progressively which attacks the surrounding area thereby dissolving the iron of boiler as sodium ferrate.
This causes the formation of irregular inter-angular cracks on the boiller metal particularly at place of high local stress like bends, joints , rivets etc. Caustic embrittlement is a case of stress corrosion and is a localized electrochemical phenomenon.
Rest of the terms we'll discuss in the 2nd part
By :- ADARSH GUPTA
Besides this hardness of water is never present in the form of calcium carbonates because it is insoluble in water and also hardness is actually caused by bicarbonates, chlorides ,and sulphates of calcium and magnessium
Calcium carbonate is used as the standard reporting of hardness of water is due to following reasons
1. The very first reason is that its molecular weight is exactly 100 and its equivalent weight is 50 so ,it makes calculation easy.
2. An another reason for using calcium carbonates is that it is most insoluble salt ,that it can be pricipitated in water treatment process
Formula used for the calculation is
=[weight of hardness producing substances in mg/L]*[100]÷[chemical equivalent of hardness causing substances]*2
MF (multiplication factor) = molar weight of CaCO3/2*chemical equivalent of hardness causing substances
2. Breake point chlorination or free residual chlorination :- chlorination is done for the the treatment of water for not only to treat the living organisms of water but also to destroy the organic inpurities this process is known as break point chlorination
While chlorine is added into water it is used for different reaction such as oxidation of reducing substances present ,chlorination of any organic substance and also free ammonia living behind mainly free chlorine which possess disinfection action against paythogenic bacteria it is also known as free residual chlorination
A typical relationship between the amount of chlorine added to water and the free residual chlorine (experimently determined).
The addition of chlorine at break point is known as break point at which free residual chlorine begins to appear normally all tastes odors disappears at break point.
Caustic embrittlement :- During this phinomina the boiller material becomes brittle due to the accumulation of caustic substance
It is a form of corrosion caused by high concentration of sodium hydroxide in boiler water
It is most likely to occur in boillers operating at high pressure where NaOH is produced in the boiler by hydrolysis of some residual Na2CO3o obtained from water softening process like lime soda
Na2CO3 + H2O -----------> 2NaOH + CO2
The formation of NaOH makes the boiler water caustic this caustic water penitrates into the minute hair cracks present in the inner side of boiller by capillary action
When the water evaporates and the concentration of dissolve NaOH increases progressively which attacks the surrounding area thereby dissolving the iron of boiler as sodium ferrate.
This causes the formation of irregular inter-angular cracks on the boiller metal particularly at place of high local stress like bends, joints , rivets etc. Caustic embrittlement is a case of stress corrosion and is a localized electrochemical phenomenon.
Rest of the terms we'll discuss in the 2nd part
By :- ADARSH GUPTA
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