Construção e avaliação da eficiência de sistema de leito cultivado no tratamento de águas cinzas

Abstract

The main objective of this work was to build a constructed wetland system of greywater in a rural property located in Nova Bilac district of Floraí - PR. The technical standards of ABNT NBR 7229:1993 - Design, construction and operation of septic tank systems and NBR 13969:1997 - Septic Tanks - Complement treatment units and final discharge of liquid influents - Design, construction and operation were used to dimension the system. Survey collecting and planting of macrophytes Echinodorus sp. and Pontederia parviflora Alexander were carried out and then the construction of the treatment plant. The system was monitored by physical-chemical analyses in a period of three months in intervals of 30 days. The physical-chemical parameters analyzed were pH, temperature, volatile acids, raw COD, filtered COD, phosphorus and total solids. The treatment system was composed by grease trap, septic tanks and cultivated bed. The volume and dimensions of the values of the components were obtained with the dimensioning, being a grease trap of 20 L, two septic tanks of 40 L and a cultivated bed of 3 m3 (2,0 m x 1,5 m x 1,0 m). The flowrate of greywater measured in the building was 565 L/d. It was possible to verify results of pH of 7,2 to the influent and 8,9 to the effluent, temperature of 22oC to the influent and 24oC to the effluent, removal efficiencies of organic matter of 83,5% and total solids of 49%.