Updated: Feb 13, 2020
Simple procedures such as boiling or use of Activated carbon filter are not sufficient for treating all possible contaminants that may be present in water from an unknown source. Many water treatment research experiments are done, that improves the quality of water to make it more acceptable for a specific end use.
The quality requirements for water need to be considered three principal aspects .
Concentration and nature of dissolved chemicals.
Color and turbidity.
Role of Ammonium Bicabonate ( NH4HCO3) in water treatment research experiment:
Ammonium bicarbonate readily degrades to carbon dioxide, water and ammonia . It is thermally unstable hence the reaction solution is kept cold, which allows the precipitation of the product as white solid.
when 30% ammonium bicarbonate solution added in grey water it reacts with the calcium salts,sulfate salts which are useful as fertilizers as well as the water after this treatment can be used for watering plants. Also reacts with some salts to form carbonates which are also useful as hard residues for making sculptures , molds etc.
THEREFORE we can conclude that Ammonium Bicarbonate is a green water treatment source with minimum waste.
Role of Aluminum sulfate [Al2(SO4)3] in water treatment research(Alum):
Aluminum sulfate is a solid white colored chemical compound. The chemical formula of the aluminium sulfate is Al₂(SO₄)₃. This chemical compound is highly reactive with the water,it produces aluminium hydroxide while reacting with the water and this aluminium hydroxide is also white in color .
Aluminium sulfate is used in water purification In water purification, it causes suspended impurities to coagulate into larger particles and then settle to the bottom of the container more easily. This process is called coagulation or flocculation.
Aluminum sulfate is widely used as a flocculant in water treatment plants. It is sold in blocks of soft white stone, and generally called alum. It is also sometimes used in swimming pools to decrease the cloudiness of the water.
The EPA has recommended a Secondary Maximum Contaminant Level (SMCL) of 0.05–0.2 mg/L for aluminum in drinking water.
Role of Chlorine in water treatment research:
When chlorine is added to water, it destroys the membrane of many microorganisms and kills them. Continuous chlorination is most commonly used in piped water supplies.
Chlorine gas is the least expensive form of chlorine to use. The typical amount of chlorine gas required for water treatment is 1-16 mg/L of water. Different amounts of chlorine gas are used depending on the quality of water that needs to be treated.
Chlorine is a highly efficient disinfectant, and is added to public water supplies to kill disease-causing pathogens, such as bacteria, viruses, and protozoans, that commonly grow in water supply reservoirs and in storage tanks. The three most common chlorine-containing substances used in water treatment are chlorine gas, sodium hypochlorite, and calcium hypochlorite. The choice of the chlorine type to be used often depends on cost, on the available storage options and on the pH conditions required.
Swimming pools need chlorine to keep the water clean and safe to swim in. Chlorine helps keep water clean by preventing the growth of algae. It keeps pool water safe by attacking and neutralizing harmful bacteria and microorganisms.
Role of Ion exchange resins in water treatment research of Heavy metals removal:
The best method for groundwater heavy metal removal is the use of a selective ion exchange resin.
Heavy metals are present in ground water and are usually Nickel, Lead, Cadmium and Zinc.
These metals are present in water at ppb level under cationic form such as Zn2+, Ni2+, Cd2+ and Pb2+. Ion exchange resins need to be regenerated after application, after that, they can be reused. But every time the ion ex-changers are used serious fouling takes place. The contaminants that enter the resins will not be removed through regeneration; therefore resins need cleaning with certain chemicals. Chemicals that are used are for instance sodium chloride, potassium chloride, citric acid and chlorine dioxide. Chlorine dioxide cleansing serves the removal of organic contaminants on ion exchange resins. Prior to every cleaning treatment resins should be regenerated. After that, in case chlorine dioxide is used, 500 ppm of chlorine dioxide in solution is passed through the resin bed and oxidizes the contaminants.