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Bitumen fume condensate (BFC) is a hazardous wastewater generated at asphalt reclamation and production sites. BFC contains a wide variety of potentially toxic organic pollutants that negatively affect anaerobic processes. In this study, we chemically characterized BFC produced at an industrial site and evaluated its degradation under anaerobic conditions. Analyses identified about 900 compounds including acetate, polycyclic aromatic hydrocarbons, phenolic compounds, and metal ions. We estimated the half maximal inhibitory concentrations (IC50) of methanogenesis of 120, 224, and 990 mgCOD·L−1 for three types of anaerobic biomass, which indicated the enrichment and adaptation potentials of methanogenic biomass to the wastewater constituents. We operated an AnMBR (7.0 L, 35 °C) for 188 days with a mixture of BFC, phenol, acetate, and nutrients. The reactor showed a maximum average COD removal efficiency of 87.7 ± 7.0 %, that corresponded to an organic conversion rate of 286 ± 71 mgCOD−1·L−1d−1. The microbial characterization of the reactor's biomass showed the acetoclastic methanogen Methanosaeta as the most abundant microorganism (43 %), whereas the aromatic and phenol degrader Syntrophorhabdus was continuously present with abundances up to 11.5 %. The obtained results offer the possibility for the application of AnMBRs for the treatment of BFC or other petrochemical wastewater., Sanitary Engineering

Treating petrochemical wastewater is a challenge for conventional anaerobic reactors. One example is coal gasification wastewater that, besides its salinity, is rich in toxic and inhibitory aromatics, such as phenol, cresols, and resorcinol. Studies have shown that phenol and p-cresol share the same degradation intermediates, whereas resorcinol is degraded via another route. This study investigated the simultaneous degradation of p-cresol or resorcinol with phenol under anaerobic saline conditions. Batch experiments with anaerobic phenol-degrading biomass were conducted to assess the feasibility of the degradation of p-cresol and resorcinol. Volumetric uptake rates of 11.4 ± 2.4 mgp-cresol·L–1d–1 and 4.2 ± 1.9 mgresorcinol·L–1d–1 were determined. The effect of p-cresol and resorcinol on the specific methanogenic activity and the cell viability in phenol-degrading and non-adapted biomass was assessed. Half maximal inhibitory concentration (IC50) values of 0.73 gp-cresol·L-1 and 3.00 gresorcinol·L-1 were estimated for phenol-degrading biomass, whereas IC50 values of 0.60 gp-cresol·L-1 and 0.25 gresorcinol·L-1 were estimated for the non-adapted biomass. p-Cresol caused a higher decrease in the non-damaged cell counts in comparison to resorcinol. Two anaerobic membrane bioreactors under saline conditions [8 g Na+·L–1] were fed with mixtures of either phenol-p-cresol or phenol-resorcinol. At an influent phenol concentration of 2 g·L-1, maximum conversion rates of 22 mgp-cresol·gVSS-1d–1 and 16 mgresorcinol·gVSS–1d–1 were found. In both AnMBRs, Syntrophorhabdus sp. and Methanosaeta sp. were the most abundant bacteria and methanogen, respectively. The feasi, Sanitary Engineering

Treating petrochemical wastewater is a challenge for conventional anaerobic reactors. One example is coal gasification wastewater that, besides its salinity, is rich in toxic and inhibitory aromatics, such as phenol, cresols, and resorcinol. Studies have shown that phenol and p-cresol share the same degradation intermediates, whereas resorcinol is degraded via another route. This study investigated the simultaneous degradation of p-cresol or resorcinol with phenol under anaerobic saline conditions. Batch experiments with anaerobic phenol-degrading biomass were conducted to assess the feasibility of the degradation of p-cresol and resorcinol. Volumetric uptake rates of 11.4 ± 2.4 mgp-cresol·L–1d–1 and 4.2 ± 1.9 mgresorcinol·L–1d–1 were determined. The effect of p-cresol and resorcinol on the specific methanogenic activity and the cell viability in phenol-degrading and non-adapted biomass was assessed. Half maximal inhibitory concentration (IC50) values of 0.73 gp-cresol·L-1 and 3.00 gresorcinol·L-1 were estimated for phenol-degrading biomass, whereas IC50 values of 0.60 gp-cresol·L-1 and 0.25 gresorcinol·L-1 were estimated for the non-adapted biomass. p-Cresol caused a higher decrease in the non-damaged cell counts in comparison to resorcinol. Two anaerobic membrane bioreactors under saline conditions [8 g Na+·L–1] were fed with mixtures of either phenol-p-cresol or phenol-resorcinol. At an influent phenol concentration of 2 g·L-1, maximum conversion rates of 22 mgp-cresol·gVSS-1d–1 and 16 mgresorcinol·gVSS–1d–1 were found. In both AnMBRs, Syntrophorhabdus sp. and Methanosaeta sp. were the most abundant bacteria and methanogen, respectively. The feasi, Sanitary Engineering