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Flotação aplicada ao pós-tratamento do efluente de reator anaeróbio de leito expandido tratando esgoto sanitário
| Content Provider | Semantic Scholar |
|---|---|
| Author | Penetra, Rogério Gomes Reali, Marco Antônio Penalva |
| Copyright Year | 2003 |
| Abstract | PENETRA, R.G. (2003). Flotation applied to the post-treatment of effluents from expanded bed anaerobic reactor treating domestic sewage. São Carlos, 2003. 288p. Tese (Doutorado) – Escola de Engenharia de São Carlos, Universidade de São Paulo. This research work presents ad discusses the results of a wide and deep study on the main operational parameters of DAF while used for the post-treatment of effluents from a pilot expanded-bed anaerobic (RALEx) reactor. The system received 10 m per hour of domestic sewage. Bench-scale assays in flota-test units were first carried out to achieve the best dosage of coagulants (ferric chloride), the best polymer and respective dosages, the adjusted pH for coagulation, the flocculation time (Tf), the proper velocity gradient (Gf) and the amont of air (S*) required. In order to obtain the proper operational conditions in the pilot DAF plant, Tf and Gf were made to vary from zero to 24 minutes and from 40 to 100 s , respectively. The chemicals ferric chloride and synthetic polymer concentrations ranged from 15 to 92 mg.l and 0.25 to 7.0 mg.l, repectively. S* varied from 2.85 to 28.5 grams of air per cubic meter of wastewater and the applied flotation rates ranged from 180 to 250 m.m.d. DAF performance was also investigated during RALEx start-up period. At the DAF operational conditions of 50 mgFeCl3.l, Tf of 15 min, Gf of 80 s, S* of 19.7 g of air per m of wastewater and the applied loading rate of 180 m.m.d, the removal efficiencies attained 80.6% for COD, 90.1% for phosphorus, 92.1% for suspended solids, producing effluents with turbidity ranged from 1.6 to 15.4 NTU, residual Fe of 0.5 mg.l, removing 77 grams of SST per cubic meter of wastewater. At the same conditions, the system RALEx-DAF presented global efficiencies of 91.6% for COD, 90.1% for phosphorus and 96.6% for suspended solids. The utilization of dissolved-air flotation (DAF) constitutes an attractive alternative for the post-treatment of anaerobic reactor ́s effluents. If coagulation is well adjusted, such system composed of anaerobic reactor followed by DAF can achieve excellent organic matter removal, expressive solids and phosphorus reduction and precipitation of dissolved sulfide generated in the anaerobic unit. Good results were also obtained even when RALEx produced low quality effluents during start-up period. In such period, the DAF unit functioned as an efficient barrier for avoiding the emission of low quality system effluent. |
| File Format | PDF HTM / HTML |
| DOI | 10.11606/T.18.2016.tde-08062016-093359 |
| Alternate Webpage(s) | https://teses.usp.br/teses/disponiveis/18/18138/tde-08062016-093359/publico/Tese_Penetra_RogerioG.PDF |
| Alternate Webpage(s) | https://doi.org/10.11606/T.18.2016.tde-08062016-093359 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
