Which of the following statements pertaining to drinking water treatment are tru
ID: 1823773 • Letter: W
Question
Which of the following statements pertaining to drinking water treatment are true?1. Small particles that do not settle in the sedimentation basin are removed in the filter
2.Filters must be backwashed when the effluent turbidity is lower than some critical (predetermined) value
3. A common water treatment goal is to provide water with hardness in the range of 175 to 220 mg/L as CaCO3
4. Hardness is defined as the sum of all cations
5. Filters must be backwashed when the headloss across the filter is too high
Explanation / Answer
1, 3 , 5 are true