Wetland treatment (HSSP) of wastewater from a milk-processing unit using Bambusa vulgaris, Typha latifolia and Cyperus rotundus.

Abstract

Studies were conducted in soil-less horizontal sub-surface flow wetland (HSSF) embedded with graded gravels using Golden bamboo, Bambusa vulgaris (a non-wetland species), Typha latifolia and Cyperus rotundus (wetland species) for the treatment of wastewater from a milk processing unit. The wastewater was treated with a dilution ratio of 3:1. Removal efficiencies of BOD and COD were studied at one, two and three days hydraulic retention time (HRT). At one day HRT, the removal efficiency (%) of these parameters was lower in comparison to when the wastewater was subjected to two and three days HRT. The increase in removal efficiency with increase in HRT was marginal when it was increased from 2 days to 3 days. The percentage removal of COD and BOD at two days retention time followed the order: Golden bamboo (93, 88) > Cyperus rotundus (91, 90) > Typha latifolia (85, 87).