A description of three methods for the determination of the initial inert particulate chemical oxygen demand of wastewater

Abstract

Three different methods are described for the determination of the initial inert particulate organics, measured in terms of COD. The methods involve experimental procedures using batch reators and are designed to differentiate residual particulate products generated by metabolic activities during the treatment processes. In the first method, the final threshold value of the particulate COD is monitored in an aerated batch reactor fed by the initial total COD. The second method uses the threshold values of the total and soluble COD in two parallel batch reactors, one fed with unfiltered and the other with filtered wastewater. The third method involves running three batch reactors, two with the wastewater to be studied and the thired with glucose. One method has been experimentally tested to assess the inert particulate fractions of domestic and textile wastewaters.

COD fractionation and biodegradation kinetics of segregated domestic wastewater: black and grey water fractions

“…Soluble non-biodegradable COD fractions of grey and black water were experimentally determined according to the procedure proposed by Orhon et al 31 For each wastewater, two reactors were run, one fed with raw wastewater and the other with wastewater filtered using a 0.45 µm filter. The reactors were seeded with small amounts of biomasses taken from the MBRs treating the same wastewaters.…”

Effect of dual substrate environment on the formation of intracellular storage biopolymers

“…In this study, typical concentration profiles of acetate, COD, PHB and OUR within a representative cycle of SBR operation at steady state are illustrated in Figure 2. The first experimental observation is the significant difference between acetate and COD concentrations; acetate was almost completely removed, while a COD level of around 35-40 mg/L persisted throughout the cycle, due to soluble microbial products (SMPs) generated as part of the metabolic activities associated with substrate utilization and microbial growth [26,27]. This observation confirms again that the effluent COD should not be regarded as part of the unutilized influent biodegradable COD, but only residual COD, either initially present or generated within the biological reactor.…”

The effect of mixing pharmaceutical and tannery wastewaters on the biodegradation characteristics of the effluents

“…Particulate and soluble inert COD for the tannery wastewater was determined with the aid of methods proposed by Orhon et al [28] and Orhon et al [29]. The inert COD test involved three aerated batch reactors, of 3 L volumetric capacity each, one fed with the unfiltered wastewater, C T1 , and second with the filtered wastewater, S T1 and, the third the glucose wastewater, S G1 .…”