Stirred anaerobic sequencing batch reactor containing immobilized biomass: a behavior study when submitted to different fill times

Abstract

The effect of the filling stage on the behavior of a mechanically stirred anaerobic sequencing batch reactor containing biomass immobilized on 1 cm polyurethane foam cubes was investigated. The reactor was made of acrylic with a capacity of 6.3 L, treating per cycle 2.5 L synthetic low-strength wastewater with a concentration of 500 mgCOD/L, at 30+/-1 degrees C. Eight-hour cycles (tC) and agitation of 500 rpm were utilized. At the beginning of each cycle 60% of the wastewater volume was treated, sufficient to completely cover the bed. The remaining volume was added at different fill times (tF) of 10, 120, 240, 260 and 480 min. The results obtained showed that ratios of tF/tC < or = 0.5 enabled organic matter removal higher than 75% and 70% for filtered and non-filtered samples, respectively. Ratios of tF/tC > 0.5, despite operation stability, resulted in loss of efficiency and formation of viscous material, similar to extra-cellular polymeric substances.

Effect of Fill Time on the Performance of Pilot-scale ASBR and AnSBBR Applied to Sanitary Wastewater Treatment

“…Within this context, it should be mentioned that Ratusznei et al [3] verified that composition and concentration used in the synthetic influent indicated that reduction in efficiency occurred due to probable exposure to air and formation of extracellular polymers, especially at longer fill times (t F /t C ) and not due to the possibility of toxic effects, according to results obtained by Borges et al [4]. Results of profiles run during the operation cycle of organic matter, BA and TVA confirmed non-occurrence of toxic effects.…”

“…The synthetic wastewater used in their work was based on carbohydrates (sucrose, starch, and cellulose), protein (meat extract), lipids (soy bean oil) at a total concentration of 500 mgCOD/L, and sodium bicarbonate (200 mg/L). Formation of extracellular polymers was minimized when the biomass was not exposed to air according to results obtained by Borges et al [4]. Since in the assays with sanitary wastewater no extracellular polymers were formed even at longer fill times, it is believed that the composition of the synthetic wastewater likely stimulated in some way formation of these polymers.…”

“…The authors noticed that under fedbatch conditions system efficiency dropped, especially for longer fill times; this decrease was caused by the exposure to air of the biomass without liquid during the fill period. Regarding the same topic, Borges et al [4] assessed the effect of the fill stage on the behavior of a fed-batch operated mechanically stirred anaerobic sequencing reactor (6.3 L) containing immobilized biomass on polyurethane foam, treating synthetic wastewater (500 mg COD L −1 ) with 8-h cycle length (t C ). Of the total volume of wastewater fed per cycle, 60% was fed at the beginning of each cycle, sufficient to completely cover the bed, and the remaining volume was added at different fill times (t F ).…”

Estudo da produção de biohidrogênio em AnSBBR com recirculação da fase líquida tratando água residuária sintética: efeito da carga orgânica

“…Estudos sobre a influência de variáveis de processo sobre a eficiência e estabilidade do reator anaeróbio operado em batelada sequencial quando aplicado ao tratamento de diferentes efluentes têm sido encontrados em literatura, como os relacionados: (i) ao tipo de mistura, a qual poderá ser implementada por recirculação da fase líquida (Brito et al, 1997;Camargo et al, 2002;Bergamo et al, 2009;Bezerra et al, 2009) ou por agitação mecânica (Angenent et al, 2002;Rodrigues et al, 2003;Rodrigues et al, 2004;Damasceno et al, 2008;Michelan et al, 2009); (ii) ao tempo de enchimento ou estratégia de alimentação (Bagley e Brodkorb, 1999;Shizas e Bagley, 2002;Borges et al, 2004;Orra et al, 2004;Zimmer et al, 2008;Albanez et al, 2009); e (iii) à carga orgânica (Ng, 1989;Massé e Masse, 2000;Chebel et al, 2006;Damasceno et al, 2007;Oliveira et al, 2008;Friedl et al, 2009;Oliveira et al, 2009;Novaes et al, 2010).…”

Estudo do efeito da carga orgânica, da estratégia de alimentação e da temperatura na produção de metano em AnSBBR com agitação tratando vinhaça

“…Estudos sobre a influência de variáveis de processo sobre a eficiência e estabilidade do reator anaeróbio operado em batelada e/ou batelada alimentada sequenciais contendo biomassa granulada ou imobilizada em suporte inerte (ASBR ou AnSBBR) quando aplicado ao tratamento de diferentes efluentes têm sido encontrados em literatura, como os relacionados: (i) ao tipo de mistura, a qual poderá ser implementada por recirculação da fase líquida (CAMARGO et al, 2002;BERGAMO et al, 2009;BEZERRA et al, 2009) ou por agitação mecânica (RODRIGUES et al, 2003(RODRIGUES et al, e 2004DAMASCENO et al, 2008;MICHELAN et al, 2009;NOVAES et al, 2010a); (ii) ao tempo de enchimento ou estratégia de alimentação (SHIZAS; BAGLEY, 2002;BORGES et al, 2004;ORRA et al, 2004;ALBANEZ et al, 2009;NOVAES et al, 2010b;OLIVEIRA et al, 2010;RODRIGUES et al, 2011); e (iii) a carga orgânica (MASSÉ;MASSE, 2000;CHEBEL et al, 2006;DAMASCENO et al, 2007;OLIVEIRA et al, 2008;FRIEDL et al, 2009;OLIVEIRA et al, 2009;CARVALHINHA et al, 2010).…”