3.8 Phosphorus Removal

What is the primary purpose of chemical phosphorus removal in wastewater treatment?

• Increase dissolved oxygen levels

• Reduce phosphorus concentration in effluent

• Enhance nitrogen removal

• Improve pH balance

What does pH control involve in the context of phosphorus removal?

• Maintaining a specific pH level to optimize chemical reactions

• Rapidly changing pH levels to enhance flocculation

• Ignoring pH levels for cost-effectiveness

• Decreasing pH levels to increase phosphorus removal efficiency

What role does the effluent polishing system play in wastewater treatment?

• Removing fine particles and impurities from the treated effluent

• Increasing chemical dosage

• Decreasing flocculation efficiency

• Balancing pH levels in the effluent

What can excessive alum dosage lead to in the effluent?

• Over-flocculation

• Low pH levels

• Sludge depletion

• Inadequate flocculation

What is the purpose of the effluent treatment in alum flocculation?

• Adjusting pH levels

• Removing excess alum

• Separating sludge

• Disinfection

What is the target pH level in alum flocculation for effective phosphorus removal?

• pH 1-3

• pH 7-8

• pH 10-12

• pH 14

What does the lime precipitation process aim to achieve?

• Increase phosphorus concentration

• Decrease pH levels

• Reduce phosphorus concentration in effluent

• Enhance nitrogen removal

Which operational parameter is crucial for effective flocculation in lime precipitation?

• Temperature

• Temperature

• Turbidity

• Mixing intensity

How does recarbonation control contribute to lime precipitation?

• Increases lime concentration

• Stabilizes pH by adding CO2

• Reduces mixing intensity

• Enhances flocculation

Which of the following is a purpose of the lime storage and feeding system?

• Increase effluent turbidity

• Maintain lime freshness

• Ensure a continuous and controlled supply of lime

• Reduce flocculation efficiency