Numerical Investigation On Flow Generated by Invent Mixer In Full-Scale Wastewater Stirred Tank

Alleyne, Alan; Xanthos, Savvas; Ramalingam, K.; Temel, K.; Li, H.; Tang, Hansong

doi:10.1080/19942060.2014.11083303

Cited by 4 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, Deglon and Meyer [36] demonstrated that predictions can be improved by applying very fine grids and higher order discretization schemes. The latter modeling strategy was successfully applied for CFD modeling of lab scale cylindrical [36,37,39] and square [40,41] stirred vessels. The latter modeling strategy was also applied here.…”

Section: Steady State Model Developmentmentioning

confidence: 99%

See 1 more Smart Citation

The Impact of Local Hydrodynamics on High-Rate Activated Sludge Flocculation in Laboratory and Full-Scale Reactors

et al. 2020

View full text Add to dashboard Cite

High rate activated sludge (HRAS) processes have a high potential for carbon and energy recovery from sewage, yet they suffer frequently from poor settleability due to flocculation issues. The process of flocculation is generally optimized using jar tests. However, detailed jar hydrodynamics are often unknown, and average quantities are used, which can significantly differ from the local conditions. The presented work combined experimental and numerical data to investigate the impact of local hydrodynamics on HRAS flocculation for two different jar test configurations (i.e., radial vs. axial impellers at different impeller velocities) and compared the hydrodynamics in these jar tests to those in a representative section of a full scale reactor using computational fluid dynamics (CFD). The analysis showed that the flocculation performance was highly influenced by the impeller type and its speed. The axial impeller appeared to be more appropriate for floc formation over a range of impeller speeds as it produced a more homogeneous distribution of local velocity gradients compared to the radial impeller. In contrast, the radial impeller generated larger volumes (%) of high velocity gradients in which floc breakage may occur. Comparison to local velocity gradients in a full scale system showed that also here, high velocity gradients occurred in the region around the impeller, which might significantly hamper the HRAS flocculation process. As such, this study showed that a model based approach was necessary to translate lab scale results to full scale. These new insights can help improve future experimental setups and reactor design for improved HRAS flocculation.

show abstract

Section: Steady State Model Developmentmentioning

confidence: 99%

“…The latter modeling strategy was also applied here. In the literature, there are only a few numerical studies of full scale hyperboloid shaped impellers [39]. In this work, the flow field generated by the hyperboloid impellers was simulated using a similar approach as the one used for the lab scale jar tests.…”

Section: Steady State Model Developmentmentioning

confidence: 99%

The Impact of Local Hydrodynamics on High-Rate Activated Sludge Flocculation in Laboratory and Full-Scale Reactors

et al. 2020

View full text Add to dashboard Cite

show abstract

“…in anoxic and aerobic tanks, coagulators/flocculators, fermenters, sludge conditioning tanks etc. (see Alleyne et al 2014;Karpinska & Bridgeman 2016Skáfár et al 2016).…”

Section: Introductionmentioning

confidence: 99%

Statistical analysis of fine resolution flow datasets helps characterizing flow behaviour in primary clarifiers: a decision support method

Kiss

Patziger

2021

Water Practice and Technology

View full text Add to dashboard Cite

In situ measurement campaigns of primary clarifiers are rarely implemented properly, because of their cost, time and energy demand. Hydrodynamic modelling possibilities for such reactors have been intensely examined recently, but on-site factors affecting flow characteristics (e.g. flow distributors) have not received sufficient attention. This paper describes the use of ANOVA in examining fine resolution flow datasets and the related decision support method for in situ measurement campaigns and subsequent modelling processes. The characteristics of the flow and the applicability of 2D and 3D methods to investigate hydrodynamic features are discussed through the example of a rectangular primary clarifier, also considering the reproducibility of measurements ranging from typical nominal flow rates to peak loads. Based on the data, recommendations are provided on the adequate sizing of a measurement campaign, potentially reduced to a single longitudinal section (2D measurement). According to our results, performing hydrodynamic measurements with a 2D-arrangement of measuring points is sufficient in the case of such clarifiers, also with regard to the design processes. When applying the described methods, the related efforts and costs may be reduced and estimated more easily. However, care should be taken when applying this method to determine the spacing of measuring points correctly.

show abstract

Computational fluid dynamics analysis of Trichosporon fermentans flocculation in refined soybean oil wastewater and flocculation rate prediction method

Jin

Yue

Wang

et al. 2022

Science of The Total Environment

View full text Add to dashboard Cite

Numerical Investigation On Flow Generated by Invent Mixer In Full-Scale Wastewater Stirred Tank

Cited by 4 publications

References 22 publications

The Impact of Local Hydrodynamics on High-Rate Activated Sludge Flocculation in Laboratory and Full-Scale Reactors

The Impact of Local Hydrodynamics on High-Rate Activated Sludge Flocculation in Laboratory and Full-Scale Reactors

Statistical analysis of fine resolution flow datasets helps characterizing flow behaviour in primary clarifiers: a decision support method

Computational fluid dynamics analysis of Trichosporon fermentans flocculation in refined soybean oil wastewater and flocculation rate prediction method

Contact Info

Product

Resources

About