Chlorine Precipitation

Currently in Honduras, there are flow controllers treating water with Calcium Hypochlorite. An issue has arisen however, making it more difficult to effectively continue this type of treatment process. Calcium hypochlorite reacts with carbon dioxide to form calcium carbonate and release chlorine.

2Ca(ClO)2 + 2CO2 → 2CaCO3 + 2Cl2 + O2

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• Creating a procedure for the water treatment plant operators to perform that would result in the settlement of all calcium carbonate formed before the solution is delivered to the plant.
• Figuring out an additional chemical solution to add to the hypochlorinator that would result in a lower pH and prevent the precipitate from forming at all. This would mean finding the exact concentration and amount of acid to add into the stock tank, which would result in the desired pH and alkalinity.

FCM Chlorine Precipitation Experiments

FCM FC Chlorine Precipitation goals, challenges, and meeting minutes.

Recommendations for Honduran Communities that are Experiencing Flow Restriction Problems in the Chlorine Feed System

FC Chlorine Precipitation Experiments

Fall 2008

*Restricted Flow of Hypochlorinators

*Calcium Carbonate Settling Observations

*Leaking Bulkhead Fittings

*Volume of Water Required to Completely Dissolve Ca(ClO)2 (MathCad)

*Fall 2008 Semester Summary and Conclusions