What is the correct order of treating hard groundwater, from initial step to final step in a typical treatment plant?

(A) Disinfection
(B) Softening
(C) Aeration
(D) Filtration

Choose the correct answer from the options given below:

Correct option is A

The treatment of hard groundwater typically follows these general steps:

1. Aeration (C): The initial step in water treatment is aeration, where air is introduced into the water to remove dissolved gases like carbon dioxide and to allow other impurities to float to the surface for removal. This helps reduce the hardness of the water.

2. Softening (B): The next step involves softening the water, which is crucial in treating hard water. Softening typically uses chemicals such as lime or sodium carbonate to remove calcium and magnesium ions that contribute to hardness.

3. Filtration (D): After softening, the water undergoes filtration, where impurities such as suspended solids, dirt, and other particulates are removed through physical filters, typically using sand or other granular media.

4. Disinfection (A): Finally, the water is disinfected using chlorine or ultraviolet (UV) light to kill any remaining bacteria, viruses, or pathogens, ensuring the water is safe for consumption.

Thus, the correct sequence is (C), (B), (D), (A).

Information Booster:

1. Aeration helps in removing gases and improving the water's oxygen content, which is important for subsequent treatments like disinfection.

2. Softening reduces hardness by using chemicals that precipitate calcium and magnesium, making water more suitable for domestic and industrial use.

3. Filtration is essential for removing particulate matter and ensuring clear water. It uses materials like sand, gravel, or activated carbon.

4. Disinfection ensures the water is microbiologically safe and is often achieved through chemicals like chlorine or physical methods like UV treatment.

5. Hard water typically contains high levels of calcium and magnesium ions, and softening is crucial for making water suitable for use in household appliances and industrial processes.