Performance of Downflow Aerated Trickling Filters with Recycled Substrates in Reducing Organic Matter in Rural Andean Wastewater in Peru
摘要
The efficiency of trickling filters with reusable combined substrates of wood and concrete rubble in removing organic matter from domestic wastewater was evaluated. The experiment was conducted at the Tuyururi Experimental Center for 16 weeks, utilizing three filters with different surface areas (35 × 35 cm, 40 × 40 cm, and 50 × 50 cm) operated at a homogeneous flow rate of 1 m3/day each. The results showed that the largest filter (50 × 50 cm) presented the best efficiency, achieving average removals of 60.11% in COD and 70.67% in turbidity. In addition, an average biofilm thickness of 0.051 mm was observed on the concrete substrate, indicating adequate microbial colonization. The physicochemical parameters in the treated effluent remained stable, with average values of pH (~7.9), temperature (~17.5 ℃), conductivity (~0.54 mS/cm) and total dissolved solids (~272 mg/L), complying with the optimal ranges for biological processes and with retention times for the three cases constantly decreasing throughout the investigation. In conclusion, trickling filters with reusable substrates proved to be an acceptable and sustainable alternative for wastewater treatment in rural areas, highlighting their capacity to remove organic matter and maintain stable conditions in the effluent.