The effect of ozonation on dissolved oxygen and microbiological content in refill drinking water

Abstract

One indicator of safe drinking water is its microbiological content of 0 colonies/100 ml. Ozonation is one method for killing microbes contained in drinking water. Disinfection in refillable drinking water that uses ozone needs to be studied, considering that the drinking water put into used gallons is washed again and can be drunk directly by consumers. It should be suspected that the drinking water used from drinking refill water contains bacteria, a dangerous virus. So the purpose of this study is to find out the microbiological content in refill drinking water with variable storage time for refill drinking water. The research method used is an observational research method. The parameters observed were temperature, pH, total microbes and dissolved oxygen content where the dissolved oxygen content indirectly indicates the reaction process of ozonation and bacterial activity contained in refill drinking water. The results showed that at pH showed a decrease from day to day, things this is caused by chemical reactions and microbiological activities. TPC shows that the smallest TPC value is 1 colony/100 ml on the second day, this is due to the ozone reaction in the water here H2O2 and (OH *) are very strong oxidizers which work optimally on the second day and then increase to 13 colonies/100 ml on day 5. The result of DO examination was an increase in DO on the second day to 8.2 mg/l which afterward finally decreased again the following day, this was due to an ozone reaction and bacterial activity in the water, therefore it was recommended that storage of drinking water after ozonation be stored for 2 days, and need renewal in the cleaning and disinfection of gallons to be used.