Abstract
Based on results obtained in the laboratory a WWTP composed of a septic tank and an aerated percolating filter packed with organic media was built for a school. The system can treat 18 m 3 d -1 and was operated with a hydraulic loading rate of 0.078 (m 3 m -2 d -1). For 360 days different operational conditions including start-up; stabilization; operation with aeration and non aeration; effect of rainy season, breaks from activities due to holidays and restart; were monitored and described in the article. Once stabilized, the system was able to remove, without the need for mechanical aeration, 97% of BOD 5, 71% of COD, 93% of TKN, 11% of PO 4 --P, 95% of TSS, 96% of VSS, in addition to having a removal efficiency of 4 log units of Faecal Coliforms (FC) and 100% helminthes eggs (HE). With this quality, the treated wastewater can be chlorinated and reused to irrigate green areas and/or in toilets. Although sanitary wastewater has a high concentration of Total-N (250 mg L -1) and a C/N ratio of less than 1, the system removed 65% of Total-N. Finally it was observed that after non activity periods, there was neither system failure nor the need to re-stabilize the system.
Original language | English |
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Pages (from-to) | 1169-1177 |
Number of pages | 9 |
Journal | Water Science and Technology |
Volume | 64 |
Issue number | 5 |
DOIs | |
State | Published - 2011 |
Externally published | Yes |
Keywords
- Decentralized systems
- Organic filter media
- Sanitary wastewater
- Trickling biofilter
- Water reuse