Greywater quality changes in laboratory scale vegetative biofiltration prototypes

Greywater represents the largest component of the domestic indoor wastewater. However, it is still practically underutilize at the source or near point of its generation. Although, traditionally, a biofilteration system operates using stormwater, findings have shown the successful operation of the system using greywater in the arid regions. This research endeavor to assess how the quality of the effluent from the biofilteration system changes with different vegetation native or adoptees of the arid region. The prototype biofilters were irrigated with equal amount of synthetic greywater on a weekly basis and the water quality parameters were monitored. The Analysis of Variance (ANOVA) provided the room to statistically evaluate the consistency between the three replicas of each of the twelve species of the plants and subsequently, the significance of treatment in each of the twelve species with respect to the eight water quality parameters. Most of the plants show high consistency in the effluent between the replicas for all the water quality parameters observed. However, a significant difference was observed across different plant species. The Ficus natida and Canna indica have a better removal of pH among others, although all species have significantly reduced the pH, which keeps accumulating in all the 36 samples. Except at the earlier stages of the experiment, all the systems removed turbidity of the greywater to almost 100%. The Ficus natida, Canna indica and Penneisetum plants exhibit higher ability to improve greywater quality in the biofiltration system.