Nowadays consumption of purified water became essential.
Because India is developing industrially and all the outcomes from companies are largely mixed with the water available on the earth means water is polluted so, water should be purified what we are consuming. There are so many techniques available on the earth for example ‘wells‘ were constructed in olden days, ‘well‘ itself is known as the best source of water purification.
Water purification is the process of removing unwanted chemicals which human body not needed, micro-organisms (bacteria, virus, fungus) suspended solids, algae, organic and inorganic dissolved components and gases from available water.
There are several methods available for water purification such as,
By physical process
By biological process
- Slow sand filters
- Biologically active carbon
By chemical process
By electromagnetic radiation process
- UV light
Which method is necessary for water purification is decided by the chemical and microbiological analysis (which is expensive) is only the way to collect the information about available water.
Simple techniques for treating water at home are boiling the water, chlorination, filters, by using small porsed cloth and solar disinfection. And coming to an electric appliance that is water purifier which is much economical for the removal of microorganisms, organic and inorganic components present in the available water.
Water purification is done based on the PH value of water. Pure water PH is approximately equal to 7. If the water is saltwater PH>7, if the water is acidic PH<7.
We need to raise the PH value if the water is acidic, so by adding lime, soda ash ( sodium carbonate) and sodium hydroxide PH value of water is raised which is acidic in nature. Calcium concentration increases by adding lime thereby increasing the water hardness. Sodium carbonate is an organic sodium salt. Sodium hydroxide neutralizes gastric acid.
We need to lower the PH value if the water is salted, so by adding acetic acid ( a dilute solution of acetic acid in vinegar ), citric acid and alum (alum is a chemical compound usually a hydrated double sulfate salt of aluminium ).
When alum added to raw water (salted water ), it reacts with the bicarbonate alkalinities present in water and forms a gelatinous precipitate. ( it is a precipitate that has a jelly-like appearance, it is of a similar density to water and will float or lie suspended in the liquid). This floc attracts other fine particles and suspended material in raw water, and settles down at the bottom of the container.
When we add citric acid to salted water carbon dioxide is released *as of my knowledge.