PH of the water and the content of foreign substances in the water.
Concentration of chlorine and content of foreign substances in the water
Concentration of chlorine and contact time
PH and Temperature of water
Organics in the water
6 to 12 hours; 25 mg/L
12 to 24 hours; 25 mg/L
12 to 24 hours; 50 mg/L
12 to 48 hours; 100 mg/L
Total dissolved solids
Based on water withdrawal permit limit.
Based on system size.
Based on population.
Different for each state.
Coliform group bacteria
15 ;50; 50
25; 25; 50
15; 25; 60
25; 50; 60
At consumers' faucets
75% at locations representative of population distribution and 25% at the farthest point in the system.
At points where water enters the distribution system
At representative points within the distribution system.
Keep lubrication in and other foreign materials out.
Control water leakage from stuffing box
Prevent water leakage from the pump shaft
Help prevent shaft from warping
The stuffing box
The casing head
Vertical turbine pump
Excessive downtime due to numerous shear pins being broken
Chain comes out of foot sprocket
Unappealing to drink, undesirable taste, and possible indication of corrosion
Discolored laundry and changed taste of water, coffee, tea, and other beverages
Undesirable metallic taste and possible indication of corrosion
Added total dissolved solids and scale, indication of sewage contamination and tastes.
Increase in algae growth
PH reduction causing an increase in iron and manganese going into solution
Oxidation of organic material
Aluminum and iron
Aluminum and calcium
Iron and manganese
Calcium and magnesium
5 to 15 minutes
15 to 45 minutes
45 to 60 minutes
60 to 90 minutes
Less than 4.0
4.0 to 5.5
5.8 to 8.5
Greater than 9.0
Colloidal particles are so small that gravity has little effect on them
The zeta potential between colloidal particles is balanced by covalent bonding
Electrical phenomenon of colloidal particles predominate and control their behavior
The surface area of colloidal particles is very small compared to their mass
Van der Waals forces
Effluent flow box
At least once per week
At least every other day?
At least once per month
At least twice per day
To draw off a liquid layer from a vessel of any size without disturbing and layers above or below
To draw off the sediment at the bottom of a vessel of any size without disturbing the overlying liquid layers.
To remove the precipitate at the bottom of any size vessel.
To draw off the liquid from a vessel of any size without stirring up bottom sediment
Twice a year
Once a year
Every other year
Every three years
To reduce taste and odor problems?
To remove pathogens
To reduce corrosion
To determine the efficiency of coagulation and filtration
It is need of a backwash.
Turbidity is just starting to break through.
It is becoming more efficient in particle removal.
It is beginning to grow algae
1 - 2 ntu
2 - 4 ntu
8 - 10 ntu