Turbidity and chlorine demand reduction using alum and moringa flocculation before household chlorination in...

Area of Science:

• Environmental science
• Public health
• Water treatment technologies

Background:

• 1.1 billion people lack safe drinking water globally, leading to 1.87 million deaths annually from waterborne diseases.
• The Safe Water System (SWS) is a household water treatment effective in reducing diarrhoeal diseases in developing countries.
• High turbidity in water complicates SWS implementation, as it affects chlorine disinfection efficacy and aesthetic acceptability.

Purpose of the Study:

• To evaluate the efficacy of alum and Moringa oleifera flocculation in reducing turbidity and chlorine demand in turbid waters.
• To determine the optimal pre-treatment method for improving the effectiveness of household water disinfection in developing countries.

Main Methods:

• Assessed turbidity and chlorine demand reduction using alum and Moringa oleifera flocculation.
• Tested treatments at various turbidity levels (10, 30, 70, 100, and 300 NTU).
• Compared treatment efficacy against controls and analyzed impact on chlorine demand.

Main Results:

• Both alum and Moringa oleifera effectively reduced water turbidity.
• Alum flocculation significantly reduced chlorine demand in waters with turbidity >= 30 NTU.
• Moringa oleifera increased chlorine demand, hindering adequate chlorine residual maintenance for 24 hours.

Conclusions:

• Alum pre-treatment is recommended for turbid waters (>= 30 NTU) to optimize water disinfection with the Safe Water System.
• Moringa oleifera flocculation is not recommended as a pre-treatment step before chlorination due to increased chlorine demand.