water treatment 4

[mhdl98]

How much 12.5% sodium hypochlorite solution would it take to make 300gpm of water a 40ppm water/chlorine solution

 

[bimr]

It looks like 4.65 gal/hour.

 

[paulrau]

When calculating dosages for sodium hypo, especially in the process design you may want to take into account possible degradation of the hypochlorite over time.

 

[dalepuskas]

I agree with paulrau, but would include that the chlorine demand of the water should be considered if you required 40ppm of free chlorine for disinfection purposes.

 

[GarySCWSVI]

Here is a helpful Internet link:

http://www.hcronline.com/techdata/B/Bleach 12.5% Industrial TECH.pdf

I agree with the others regarding "chlorine demand" of the solution to be disinfected and to be aware of "degradation" of the chlorine prior to use as advised in the link.

Gary Schreiber, CWS VI
The Purolite Co.

 

[nohandleengin]

I am a little slow on the uptake, but if the flow rate is 300 gpm then that would be 18000 gal/hour. That would seem to come out to 0.018 gal = 1/1,000,000 of 18,000 gal. If the desire dose was 40 ppm, then that would require 40 x 0.018 gal/hr or 0.72 gal / hr cl2. If the sodium hypochlorite is a 12.5% solution, then the 0.72 gal/hr chlorine would have to be divided by the 0.125 solution leaving a feed rate for the sodium hypochlorite of 5.76 gal/hr. What am I missing here? Are you factoring in the s.g. of sodium hypochlorite? If so I find that somewhat curious as I was always told that because commerical strength hypo is based on 1% figured at one pound of chlorine per 10 gallons of water which would balance out the s.g. Is this incorrect?

 

[bimr]

Correction:

Sodium Hypochlorite Specification For 12.5 Trade Percent Available Chlorine: Delivered Grams per Liter: >120 G/L

120 G/L available chlorine =

120 G/L x 3.785 liters/gallon x 2.205 pounds/1000grams = 1 pound/gallon available Cl2

Therefore, one gallon of sodium hypochlorite at 120 GPL will equal one pound of chlorine and it has the equivalent oxidizing power.

40 mg/l Cl2 /120 = 0.33 lbs/1000 gallon

0.33 lbs/1000 gallon * 18000 gallons/her = 6.0 lbs/hr Cl2

6.0 lbs/hr Cl2 *1.0 gallon sodium Hypochlorite/1.0 lb Cl2 =

6 gallons/hr of 12.5 Trade Percent Sodium Hypochlorite

http://www.odysseymanufacturing.com/product_spec.htm