Tratamento ecológico de esgoto doméstico: TEWetland um sistema inovador com benefícios sociais e ambientais, com produção de água para reuso

Abstract

Investing in new technologies and practices, care for decentralized sewage treatment systems, is necessary, whether in the collective or single-domestic modality. Shortening sewage treatment distances from its polluting source saves resources, raw materials, energy, and avoids transferring the local problem to third parties who have nothing to do with the polluting source, but who are often left with the environmental damage. The semi-arid regions influenced managers more, in order to preserve water quality and maximize its use, in the face of scarcity. Faced with this low water availability, and the useless sewage that deteriorates the environmental quality of aquatic systems and the healthy quality of human life, the generation of water for reuse becomes doubly beneficial, preserving the quality and quantity of this resource in the springs. TEWetland, a unique mixed treatment model, designed by the research team at the Laboratory of Aquatic Ecology/UFPB, is a nature-based solution that combines the Evapotranspiration Tank (adapted) and the Constructed Wetland. This technology is made to receive both gray and black water, generating treated water effluent for reuse, and the production of food in its structure. Two prototypes were installed in the municipality of Ingá-PB, TEWetland_UPA and TEWetland_SAMU, and the effluent from the first module (TEVAP) of each was monitored. The prototypes compared to the average concentrations of BOD, COD and coliforms in the effluents, with the main secondary treatment systems, performed very well, approaching the results of Activated Sludges (AL), and in some situations, the quality is still superior. As for coliforms, the system is still not stable, however, the TEWetland_UPA in 83.3% of the results is suitable for reuse with environmental fins, 75% for urban fins, and even if still low, 25% for agricultural fins and for aquaculture. As for TEWetland_SAMU, 66.6% for environmental purposes, and 55.5% for urban purposes, based on Resolution Coema No. 02/2017, of Ceará, the only resolution in Brazil that establishes standards for water reuse from sanitary effluents. Thus, the research revealed that it is possible to present alternatives for ecological treatment of domestic sewage, using Small Collective Sewage Treatment Plants, with the generation of good quality water for reuse. The dimensions of the TEWetlands appear to be adequate, with hypothesis 1 being accepted, and hypothesis 2 of good quality of the effluent for reuse.