chlorination
types of disinfection
uv, chlorine, reverse osmosis, ozon
what is MCL for flouride
4.0 mg/l
what does CLR stand for
copper lead lead rule
A tank has a volume of 120,000 gallons and a flow of 40,000 gallons per hour. This is its detention time.
3 hours
what is the purpose of sedimentation
let heavy particles to settle
what is the mcl of chlorine in water
4.0gm/l
what is the mcl of lead
0.015 mg/l
what does sdwa stand for
safe drinking water act
Water flows into a 900-gallon basin at 30 gallons per minute. This is the detention time in minutes
30 minutes
What is another name for sedimentation
clarification
This powerful form of chlorine gas has been used for more than a century as a primary disinfectant in municipal water systems
What is chlorine gas
mcl of total colliform
less than 1
what does MRDL stand for
maximum residual disinfection level
A chlorine contact chamber holds 50,000 gallons. If the flow rate doubles from 500 gpm to 1,000 gpm, this happens to the detention time
is cut in half
What flow pattern does a rectangular sedimentation tanks have?
Rectilinear
When chlorine reacts with natural organic matter, these potentially harmful byproducts can form—two common types are THMs and HAAs
What are disinfection byproducts
what is mcl of copper
1.3 mg/l
What does TCR stand for
total colliform rule
A sedimentation tank with a volume of 15,000 ft³ receives water at 1,500 ft³/hr. This is the detention time.
10 hours
What does quiescent flow mean
Water is calm with low turbulence
Operators adjust chlorine dosage based on this parameter, which measures how long chlorine is in contact with the water before it reaches consumers
What is contact time
mcl of turbidity
0.3 NTU
what does VOC stand for
volotile organic compounds
A clearwell has a detention time of 2 hours at 1 MGD. If the flow increases to 2 MGD, this is the new detention time.
1 hour
Why are eddies bad when it comes to sedimentation
They stir up settled solids