دراسة بعض العوامل المؤثرة على كفاءة الكلور التطهيرية لماء الشرب في محطات التصفية لمدينة بغداد الكرخ

Abstract EN

This study was designed to high light about the effect of some factors individually or in combination that shared in the reduction of the chlorine activity and efficiency for meeting the bacterial standards as a disinfection agent for drinking water at Baghdad city/ Al- kurch.

To achieve the objectives (137) drinking water samples were collected from July up to the end of November 2007 from the houses of Baghdad's citizens/ Al kurch.

Also studying the scientific nature of some municipal water supply at Baghdad/ Al- kurch, drinking water samples were collected from faucets after allowing the water to run for 0, 5 and 10 minutes.

Statistical data showed that there was non significant difference in both the chlorine concentration and coliform counts in all samples that were taken after allowing the water to run for 0, 5 and 10 minutes and for that reason drinking water samples after allowing the water to run for 5 minutes were chosen as the best time for sampling in this research.

Data revealed that the free chlorine in drinking water was below the standards set by the World Health Organization (WHO) in the period from July up to the end of August 2007, whereas the highest Coliform counts in drinking water were established during the above mentioned months, while the coliform counts decreased in the period from September up to the end of November 2007 due to the utilization of higher concentrations of total chlorine in drinking water in municipal water supply, in addition to that, the effect of some variables such as quantity of free chlorine, temperature, pH and oxidation- reduction potential of water on the sanitizing efficiency of the chlorine were studied.

The statistical data revealed that there was a significant negative correlation (P < 0.01, r = -0.072) between the chlorine sanitizing efficiency with both the concentration of the free chlorine and its contact time with microorganisms while the effect of temperature, pH and oxidation- reduction potential of water showed non significant effect on the chlorine sanitizing efficiency.

In order to evaluate the sanitation program of the municipal water supply at Baghdad/ Al- kurch to ensure that the water treatment was being done properly by the employees and meeting the bacterial standards set by (WHO).

All the official documents about the chlorine concentration, pH, temperature of water that were reported by the employees in the period from July up to the end of November 2007 were studied and compared to this results, for that reason 16 drinking water samples from the municipal water supply were collected and tested for the above mentioned parameters during November using the most sensitive advanced digital instrument (Chlorimeter).

Data reported by the municipal water supply at Baghdad/ Al- kurch revealed that chlorine, pH and temperature of water were 3.6 PPM, 7.50 and 21.7Co, respectively in November only.

While the measurements were reported here 5.05 PPM, 6.94 and 17.6oC respectively, during the same month by using the Chlorimeter and the only reason for such differences with our results was due to the use of a highly sensitive digital instrument by our research in comparison to the old methods and instruments that were used in the municipal water supply.