2 questions for water distribution 2

[MILKMAN08]

What is chlorine measured in? PPM
How is pressure head caused? water elevation or tower

I am look for a discription to go along with these answers to help me understand them better. Any input would be greatly appreciated.

 

[cvg]

http://en.wikipedia.org/wiki/Parts_per_million

http://mysite.du.edu/~jcalvert/tech/fluids/bernoul.htm

 

[deccantrap]

1. Chlorine is measured by holding in a graduated jar.
2. Pressure head is caused by plugging ears, holding nose shut, and blowing hard with mouth closed.
3. Tower.

 

[jartgo]

Chlorine in water is measured in either ppm or mg/L. (The two are the same if you consider pure water, if the denisty of interest is much different, then that will have to be taken into account).

Pressure head is always caused by increase in elevation. This can be achieved either artificially (through a pump or pressurized tank), or real elevation (commonly done with a tower).

 

[nohandleengin]

ithompson is correct - chlorine is measured in the distribution system as either parts per million (ppm)or milligrams per liter (mg/L). As an example, if there was a flow rate through the water plant of 10,000,000 gallons per day that would be equal to 83,400,000 pounds per of waterper day. (1 gal water = 8.34 lb). Then if the desired dose of chlorine was 2 parts per million, the chlorine would have to be fed at 166 pounds per day (this is assuming chlorine gas).
(83,000,000)(2/1,000,000) = 166

mg/L = ppm because there are 1,000 milligrams in a gram and 1,000 grams in a kilogram (kg) and 1 liter (L) of water = 1 kg of water (or very, very close).

Head is a function of the elevation (or depth) of the water. I do not know if you saw the article, but just recently scientists filmed some fish swimming around 5 miles below the surface of the Pacific Ocean. At 0.433 psi per foot of water column, that works out to around 11,000 psi pressure head that these fish live in. Imagine what it would be like to have 11,000 pounds per square inch squeezing in from every direction - be a little tough to breath.