Influência da adição de água de produção pré-ozonizada em reator anaeróbio com biomassa imobilizada tratando esgoto sanitário

Abstract

Produced water, so called because it is associated with oil production, is na undesirable by-product that is always present in the extraction of oil. This residue is highlighted by the volume generated, toxicity and high salinity. These features imply hard treatability by biological processes, necessitating a pretreatment and / or dilution thereof with another residue to enhance their biodegradability. Thus this research proposes an alternative treatment for water oil production in biological reactor under anaerobic condition treatment preceded by pre-ozonation. The water pre-production ozonated (WPPOz) was mixed with a synthetic substrate simulating sewage (SSS) in increasing proportions in 5 operational phases. An anaerobic reactor with immobilized biomass operated sequencing batch (RBSBIan) cycles with 24 hours was fed daily with 8 L of the mixture (WPPOz + SSS). The results showed na average 75% removal of organic matter in terms of COD for stage 1 (no addition of WPPOz). In the subsequent phases has been found that the efficiency decreased with the increase of the percentage addition WPPOz, with values of 73%, 64%, 47% and 23% for stages 2 (2% WPPOz), 3 (5% WPPOz) 4 (8% WPPOz) and five (10% WPPOz), respectively. Similar behavior was observed in the process of ammonification. The kinetic constants of the decay of organic matter and ammonification confirmed the inhibition of anaerobic process. Nevertheless, the study of the temporal profile of ammonification and decay of organic matter showed that the batch reaction time could be reduced from 22 to 8 hours. These results showed that 5% is the highest percentage of dilution WPPOz in SSS for the RBSBIan operates with stability and COD removal efficiency exceeding 60%. The inhibition of anaerobic process may be attributed to osmotic stress caused by high salt, in that steps 4 and 5 were respectively 7.9 gCL-.L-1 and 11.7 gCL-.L-1.