Problem with ion-exchange resins efficiency

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Problem with ion-exchange resins efficiency

David Averbeck Sean Roop 

Hi everyone.

I made a set-up for ion-exchange resin demineralization. The water analysis is attached. the feed water is slightly sore municipal water, and the  feed debi is 200 liters per hour,  measured by a flowmeter. The cycle is getting less. in the beginning, it was around 3 m3 per cycle. It was not okay at the beginning, I thought maybe it was because of the regeneration material dilution, first, it was 20 lit HCl in 200 lit Water and 20 Kg of NaOH in 200 lit water. (The valves are automated.) I changed the volume of the regenerants as follows., but got worset. I have 3 main problems: 

1-The cycle is not 6m3 as we expected.

2- pH varies  between 3 to 14

3- Since I don't know when to stop the final rinsing sequence, I will waste the capacity of the deionizer. How can I understand when to stop rinsing?

The system Details As follows:

Cation Exchange: (Total Cation: 23.611 meq/L)

Resin: Purolite C100H ( Capacity:2.0 eq/L ) / Vol: 125 Liters / Regen by 20 liter HCl (No water added)

Vessel : FRP 12X52

Cation Exchange: (Total Cation: 23.609 meq/L)

Resin: Purolite A400OH ( Capacity: 1.3 eq/L ) / Vol: 175 Liters / Regen by 10 Kg dry NaOH in 40 lit. of water)

Vessel : FRP 14X62