Estimation of biodegradation parameters of phenolic compounds on activated sludge by respirometry

Utilisation of respirometry to assess organic matter reduction of effluents from the Camaçari industrial complex (BA, Brazil)

“…A reduction in the width of the confidence interval might originate from a smaller variation of the TE organic load compared to TE test. These large variations in the WTP effluent could greatly influence the microbial community (Orupõld et al, 2001 During the treatment of industrial wastewater, different loads released showed different oxygen uptake rates (Orupõld et al, 2001). Similarly, the composition of the microbial biomass could show certain variation (Kilroy and Gray, 1992).…”

“…Therefore, the estimation of the toxicity of chemicals to micro-organisms in the sludge is an important criterion for evaluating the environmental risk of chemicals in wastewater, protecting the WTP from toxic shock loading (Strotmann et al, 1994;Strotmann and Pagga, 1996). Indeed, the toxicity of effluents measured in the sludge reflects the integrity of the biological processes, namely respiration, and may act as an effective and reliable indicator of treatment efficiency (Orupõld et al, 2001). There is no doubt that respiration is an essential activity of aerobic bacteria and that the respiration inhibition test of activated sludge is a widely accepted parameter for monitoring activated sludge activity Gendig et al, 2003).…”

“…In this test, a decrease in dissolved oxygen concentration is recorded as a function of time. During the treatment of different kinds of substrates in industrial wastewater and due to different loads, oxygen consumption may vary considerably (Orupõld et al, 2001). When a toxicant is supplied to the activated sludge, the oxygen uptake by the micro-organisms may decrease, resulting in lower treatment efficiency or break down of the system (Kilroy and Gray, 1992;Gutierrez et al, 2002).…”

“…Thus, the oxygen uptake rate (OUR) is considered to be the key parameter for estimation of aerobic microbial transformation (Vollertsen et al, 1999). According to Roš et al (1988), biological oxygen uptake is closely related to substrate removal because it simulates the degradation processes that occur in the aeration tanks, from which the inoculum is obtained, providing a clear indication on the metabolism of the activated sludge (Dircks et al, 1999;Orupõld et al, 2001). In this study, it was aimed to evaluate the efficiency of the WTP at the Camaçari Industrial Complex (CIC) (BA, Brazil) through the assessment of organic matter reduction, using the oxygen consumption inhibition test.…”

Physiological changes of Candida tropicalis population degrading phenol in fed batch reactor

“…It can also reduce the methanogenic activity of biogranules in the waste water treatment under shock-loading conditions but some tolerance was observed too (Fang and Chan, 1997). However, phenol is easier degradable then other aromatics (Orupõld et al, 2001). Many studies have been focused on biodegradation of phenol and phenolic compounds with respect to degradation pathways (Dagley 1985, KatayamaHyraiama et al, 1991.…”