Wastewater treatment with constructed wetland in a fragile ecosystem and assessment of potential for reuse

Abstract

Currently, environmental, social and economical impacts due to water pollution and scarcity
are already severe in many parts of the world due to increasing water demand and pollution of
existing supplies. Water reuse and recycling technologies will be certainly needed in a near
future, Agriculture is responsible for 60-70% of water consumption and therefore, reuse in
such economic sector could bring expressive benefits in a water-scarcity scenario, However,
several constraints shall be removed to make possible water reuse, Among them, the treated
water shall meet the required standards regarding human and environmental health safety
aspects, Risk assessment shall demonstrate no additional risk for human and environmental
health due to reuse, The main sources for reuse are saline water, brackish water and treated
wastewater. This study evaluates the potential for reusing the effluents of a wastewater
treatment plant according to the established guidelines and standards, It describes the process
efficiency through physical, chemical and biological parameters in a wastewater treatment
system designed for 60 persons per day, operating in an island within an Atlantic Rainforest
environmental protected area in Rio de Janeiro, BraziL The system is formed by septic tank,
anaerobic biological filters, and polishing by a constructed wetland, Based on a six month
monitoring period, it was shown that the water discharged from the treatment system can be
safely used in irrigation, However it is recommended to use it in industrial processed cultures,
wood forest, fruit trees and cereals cultures