What is pulverized limestone used for in the context of water treatment?

• A. Enhancing filtration
• B. Improving water quality by coagulation
• C. Altering pH levels
• D. Reducing toxicity

Answer: (B)

Pulverized limestone is primarily used in water treatment to alter the pH levels of the water. By adding pulverized limestone, which is mainly composed of calcium carbonate, it effectively raises the pH of acidic water, making it more neutral. This process is essential because maintaining a balanced pH is crucial for preventing corrosion in pipes and ensuring the effectiveness of disinfectants used in water treatment.

It can also aid in the precipitation of certain metals and help in removing hardness from water, but its main role in water treatment relates to managing pH levels rather than improving water quality through coagulation. Coagulation typically involves substances that aggregate particles in the water to facilitate their removal, which is not the primary function of pulverized limestone. Its role is more focused on pH correction, which can indirectly contribute to overall water quality.