Size distribution of wastewater COD fractions as an index for biodegradability

Dülekgürgen, Ebru; Doğruel, Serdar; Karahan, Özlem; Orhon, Derin

doi:10.1016/j.watres.2005.10.032

Cited by 142 publications

(113 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Others investigate the relationship between the presence of protozoa in sludge and the structure and morphology of flocs on the course of the wastewater treatment process [9][10][11]. An important and currently commonly discussed tasks in wastewater treatment technology are the ways of description of physiological activity of activated [12,13] and fractioning of the substrate to build and calibrate computer models of sewage treatment systems [14][15][16][17][18]. An important aspect of investigation is also application of raw and treated sewage in agriculture [19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Impact of optical indices on particle size distribution of activated sludge measured by laser diffraction method

Sochan

Polakowski

Łagód

2014

Ecological Chemistry and Engineering S

View full text Add to dashboard Cite

Abstract:The important factors that strongly influence the particle size distributions measured by the laser diffraction method are the optical parameters of the suspension (refractive index and absorption coefficient). Knowledge of the values of these parameters is necessary for Mie theory. Mie theory is applied for conversion of the intensity of light recorded on detectors into particle size distribution (PSD) of tested material. Both wastewater and activated sludge are mixtures of a variety of elements (mineral or organic, including living organisms). In practice, it is not possible to define clearly the values of the optical parameters, as the composition of the suspension changes over time. The aim of the study was to estimate the impact of assumed values of the optical parameters on particle size distributions obtained. The PSDs of suspensions sampled in different stages of wastewater treatment are the most reproducible when the following optical parameters are defined: absorption coefficients -1.0 and the refractive index -1.52.

show abstract

Section: Introductionmentioning

confidence: 99%

Impact of optical indices on particle size distribution of activated sludge measured by laser diffraction method

Sochan

Polakowski

Łagód

2014

Ecological Chemistry and Engineering S

View full text Add to dashboard Cite

show abstract

“…Various authors have used PSD to evaluate the performances of trickling filters (Zahid and Ganczarczyk, 1990;Marquet et al, 1999Marquet et al, , 2007Schubert and Günthert, 2001). Dulekgurgen et al (2006) tried to relate the different fractions of COD in wastewater to its PSD and used PSD as an index for wastewater biodegradability. PSD has also been used as a tool to evaluate the effect of ultrasound on the suspended particles in wastewater (Gibson et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

Experimental and modeling investigation of sewage solids sedimentation based on particle size distribution and fractal dimension

2009

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

Sewage solids are usually characterized by non-specific parameters such as suspended solids. The suspended solids has been shown to be an inadequate index for advanced water treatment processes. In this study, the sewages solids particle size distribution was used to provide more detailed information on sewage characteristic. It is hoped that, by introducing particle size distribution, the mechanism of sewage solids sedimentations can be better understood. The particle size distribution of the domestic sewage was measured by the Malvern® laser scattering technique to link to its settlement efficiency. Experimental results show that 77 % of particle volume was removed during the 90 min settling, of which 71.2 % of particle volume was removed in the initial 30 min. The submicron particles were found to be removed by co-settling with large particles. The fractal dimensions of sewage solids could also be derived from the laser scattering measurement. The fractal dimension could also provide useful information on the shape and density of sewage solids. A mathematical model considering the particle sizes, shapes and density changes was then constructed to simulate the settlement of raw sewage particles. Comparison of the modeling results based on discrete and flocculant settling theory shows that settlement can be better predicted by considering the fractal nature of particles. The particle size distribution and fractal dimension data measured by Malvern® laser scattering technique have been shown to be valuable data for in-depth understanding of the mechanisms of sewage solids sedimentation.

show abstract

“…autotrophic nitrifying biomass X AUT , phosphorus-accumulating microorganisms X PAO and internal storage products of phosphorus-accumulating organisms X PHA ) are assumed to be less than 1 % of total COD, and usually, they are not measured (Pasztor et al 2009). The fractions can be quantified with a range of methods, including a combination of physical, analytical (S F ), respirometric tests (X H , S S , S I ), simulation (X I ) and mass balance calculations (X S ) (Dulekgurgen et al 2006;Mhlanga et al 2009;Mąkinia 2010;Xu and Hultman 1996;Fall et al 2012). The soluble inert fraction (S I ) can also be determined directly by analysis of coagulated and filtered effluent from an activated sludge system (Mamais et al 1993).…”

Section: Industrial Effluent Characteristicsmentioning

confidence: 99%

Determination of permissible industrial pollution load at a municipal wastewater treatment plant

Mikosz

2014

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

Industrial wastewater discharged to a municipal sewage system may often be a source of valuable organic substrate for biological processes at a municipal wastewater treatment plant (WWTP). In such situations, the pretreatment of wastewater at an industrial plant should be minimized, in order to maintain the favourable structure of organic material in influent to a WWTP. A frequent problem is how to determine the maximum industrial pollution load that can be discharged, without compromising the treatment capability of a WWTP. This article presents a method based on computer simulation that can be used for this purpose. As a result, the method produced the permissible industrial pollution load that could be discharged safely, and the relationship between chemical oxygen demand (COD) load and required biomass concentration as a function of process temperature. The method was tested at a fruit-processing plant and municipal WWTP, located in Poland. The results of this study have shown that the bioreactor should be operated at a biomass concentration varying between 3,600 and 5,400 g m -3 in function of the process temperature. Under such operational conditions, the WWTP would be able to accept the permissible industrial COD load of above 9,000 kg COD d -1 for a wide range of temperatures, namely 14-19°C. If the WWTP was operated at a constant biomass concentration, its permissible industrial COD load would be reduced to 7,500-9,000 kg COD d -1 . The method can be applied to other municipal WWTPs with activated sludge that receive industrial effluents.

show abstract

Size distribution of wastewater COD fractions as an index for biodegradability

Cited by 142 publications

References 19 publications

Impact of optical indices on particle size distribution of activated sludge measured by laser diffraction method

Impact of optical indices on particle size distribution of activated sludge measured by laser diffraction method

Experimental and modeling investigation of sewage solids sedimentation based on particle size distribution and fractal dimension

Determination of permissible industrial pollution load at a municipal wastewater treatment plant

Contact Info

Product

Resources

About