Performance evaluation of the geotextile blanket in sequential batch reactor in wastewater treatment

ABSTRACT

This work evaluated the performance of a batch activated sludge system with a filtration module, provided by a geotextile blanket to remove organic matter present in sewage. The pilot-scale reactor had a useful volume of 85L, and it was operated for 182 days, with a total cycle time of 24 hours, and sludge age (θc) 25 days. The system was based on a conventional controller (SB1), used as a control and operated under the same conditions as the reactor (SM1) using geotextile blanket filtration. The preparation of the three filtration modules was applied to a non-woven synthetic blanket combined with three types of spacers: PVC-coated non-slip polyester mesh (Step I) for 56 days, three-dimensional geo-mat of thermosolded polypropylene filament (Step II) for 49 days, and 100% polyester acrylic blanket (Step III) for 76 days. The OD concentration remained in the range of 3 mgO₂L^-1, an F/M ratio ranging from 0.2 to 0.1 gBOD₅. gVSS^-1d^-1 and the organic loading rate average applied ranged from 0.194 to 0.267 kg COD / m³.d.^-1. Turbidity removal remained in the range of 97%, and the organic matter removal in terms of BOD₅ was 93%, and from 87 to 93% in terms of COD, with SM1 reactor showing efficiency and stability values higher than SB1.

Keywords:
activated sludge; membrane bioreactor; non-woven synthetic blanket, prolonged aeration