A Comparative Analysis of Greywater Quantity and Quality Characteristics in Household and Hostels

With a view to compare the quantity and quality characteristics of greywater from different sources, raw greywater was collected from a household, a girls’ hostel and a boys’ hostel daily for four months. Mixed greywater from the hand basin, bathroom and laundry was collected in each case. The results showed that the mean greywater generation from the household, the girls’ hostel and the boys’ hostel was 60, 85 and 80 L/person/day, respectively. No significant difference in greywater generation was observed for days of the week and the months of the year for a particular source. Greywater from the household was more polluted compared to the greywater from the girls’ hostel and boys’ hostel for different physicochemical and microbiological parameters, and no significant difference was observed in the quality of greywater from the boys’ hostel and the girls’ hostel except for NH4-N. Turbidity, COD and NH4-N in greywater from the household were 258 NTU, 522 mg/L and 11.63 mg/L, while PO4-P and faecal coliforms were 5.94 mg/L and 7.8 × 104 CFU/100 ml, respectively. Copper, zinc and chromium concentrations in the greywater from the household were 65.05, 240.43 and 26 µg/L, respectively. The turbidity, organic content, PO4-P and faecal coliform concentration in household greywater were at least three times higher than those in hostel greywater, while the concentrations of Cu and Zn were at least two times higher. Results indicated that the quality of greywater was related to the quantity of greywater generation and the source of greywater needs to be considered in the selection of the greywater treatment technology.