Chapter 3 - Domestic wastewater treatment using floating raft techniques

Abstract

Floating raft techniques (FRTs) is an effective and sustainable technology for domestic wastewater treatment. This technique has been widely adopted for treatment of various kinds of polluted water, including domestic wastewater, storm water, and industrial effluents. In FRTs, plants are vegetated on a floating raft and their roots are extended down to the contaminated water, hence acting as biological filters. Nutrients and potentially toxic metals/elements are taken up from the wastewater by plants through their roots, while organic matter is degraded by the microorganisms, forming biofilms on the roots and raft surface. Furthermore, organic pollutants which are already taken up by the plants are degraded by endophytic bacteria in plants. The present article provides an overview of FRTs, factors responsible for performance of FRTs, and their applications for wastewater treatment. Last, the potential role of the combined use of plants and bacteria in FRTs for the maximum remediation of polluted water is emphasized.