Chlorine injector line

[CBollin]

Is it normal to hook the Chlorine injector line to piping after the holding tank and the chlorination pump is activated by a flow meter looks like a cob job? Is it not the norm to inject Chlorine directly into the holding tank? What is the down side to hooking the chlorination line into the holding tank feed line? So that the chlorine is injected into the water before going into the tank.

 

[BigInch]

Sitting around in a tank it'll have to much time to react with other things. Clorine is best used freshly mixed.

What would you be doing, if you knew that you could not fail?

 

[bimr]

It is not normal to have a chlorine holding tank. Chlorine in normally fed inline.

http://10statesstandards.com/waterstandards.html#4.3

 

[CBollin]

The chlorine mixture is held in a crock with a 2 to 1 ratio ( 5 gal chlorine to 10 gals of water). The water is pumped from the well into a 30,000 gallon holding tank. The configuration I saw was the line from the chlorination pump was hooked into the water main on the discharge pipe of the water holding tank. The chlorination pump was activated by a flow meter. Would it be beneficial to chlorinate the water in the 30,000 gallon tank? Is there a contact time for chlorination?

 

[BigInch]

No. There is a "deactivation" time. Kind of like why you have to keep on putting clorine in a swimming pool on a regular basis, even though you didn't change out the water.

What would you be doing, if you knew that you could not fail?

 

[bimr]

Yes there is a contact time for chlorine disinfection. Surface water treatment makes use of a contact time. However, with wells, the well is assumed to be organic contamination free so that a contact time is not required. Sometimes when a well is contaminated, a condition known as a well under the influence of surface water, the water disinfection requirements are more more rigorous and a contact time is required for well disinfection.

Your initial post lacked details to understand just what you are trying to accomplish.

If you have a water reservoir, then yes you should chlorinate prior to the water entering reservoir. Keeping the water reservoir chlorinated will improve the disinfection process through providing some contact time.

http://www.aeespfoundation.org/publications/pdf/AEESP_CS_5.pdf

 

[77JQX]

Where to chlorinate depends on details you haven't provided, especially holding times. If you add chlorine before the holding tank, and the holding time in your 30,000 gallon tank is long (and what long means depends on temperature, protection from sunlight, etc.), then your chlorine may dissapate before reaching the distribution system. Or with a long holding time, if you have organics present, you may form harmful disinfection byproducts. So, if you have a long holding time, adding chlorine after the holding tank is a good idea.

However, chlorine takes time to be effective, and the length of time depends on the chlorine dose, temperature, and pH of the water. Google "CT disinfection" to learn more about this. If holding time is short, it better to add chlorine before the holding tank to allow time for the chlorine to react.

And in some cases, you may want to inject chlorine in both locations - before the tank to prevent biological activity in the tank, and after the tank to compensate for chlorine losses due to a long holding time.

 

[bimr]

Since this is well water, there should not be any organics present. If organics are present, then the well should be repaired and disinfected.

One would not have to chlorinate after the water storage tank unless the storage volume exceeds 2-3 days holding time. Since this is such a small tank, one would not think this is possible.