Comparação de wetlands construídos de escoamento subsuperficial vertical e horizontal no tratamento de água resíduária

Abstract

Simple sewage treatment systems are increasingly needed in places where there are few resources for sewage collection and treatment. Constructed wetlands systems (CWS) have advantages because of their low construction and maintenance costs. The objective of this work was to evaluate and compare the performance of four CWS operating in a batch regime, two of which are vertical and horizontal flow vegetation with the species Zantedeschia aethiopica (L.) Spreng; And two nonvegetated systems, used as control. PH, temperature, dissolved oxygen, phosphorus, nitrite, nitrate, ammoniacal nitrogen, COD, turbidity and conductivity in samples of the inffluent and effluent of the systems were determined. A kinetic study was also carried out regarding the removal of COD. The maximum removal efficiencies of phosphorus were 65.5% in the horizontal flow and 96.9% in the vertical flow; Ammonia nitrogen, nitrite and nitrate were higher than 27%, reaching 90.4% of ammoniacal nitrogen removal in the vertical system. The applicability of the macrophytes after their use was analyzed, incorporating them to the concrete blocks, which were evaluated through tests of bending, compression and moisture content. The tests showed that the addition of the fiber from the CWS macrophytes contributed to the increase in the toughness of the concrete.