Nucleation and crystal growth kinetic parameter optimization of a continuous Poiseuille flow struvite crystallizer using a discretized population balance and dynamic fluid model

Burns, Max William; Sheehan, Madoc; Schneider, P. A.

doi:10.1016/j.cej.2020.126607

Cited by 10 publications

(12 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is mirrored in the academic literature, where a majority of struvite work focuses on soluble P removal through crystallization with limited data available on how much P is actually harvested from a reactor as a fraction of influent TP. From laboratory studies, the potential for fines loss on larger scales is evidenced mainly in particle size distributions (PSDs) that often are populated with crystals smaller than 200 μm. − Although crystallization reactors can be designed to account for some amount of fines production through seeding ,,,, or operational controls and conditions, ,,, pilot and full-scale studies indicate the prevelance of fines washout. In pilot struvite crystallization systems, reported P removal is good ranging from 78 to 93% while recovery varies from 7 to 91% mainly due to fines loss. − Full-scale struvite crystallization systems also report fines issues with one plant producing up to 70% of its total struvite as fines (self-defined as particles <0.5 mm) depending on the operating conditions and others estimating a P recovery of only 22% .…”

Section: Introductionmentioning

confidence: 99%

“…Since the introduction of a strictly thermodynamics-based model for precipitation, many studies have built upon mass-based frameworks for use in plantwide modeling. ,,, Although the models included in these studies have been shown to fit equilibrium results well, they lack the ability to predict crystallizer effluent PSDs. The inclusion of a population balance equation, known as population balance modeling (PBM), allows for prediction of crystallizer effluent PSDs and can include nucleation, crystal growth, and aggregation. ,− ,,, Unlike the mass-based activated sludge models (ASMs), the PBM tracks particle size and number to estimate area dependent growth and dissolution. Improvements have been made to struvite PBM by choosing mass as the internal coordinate and including the effects of shear on nucleation and growth. ,, Despite these improvements, difficulties still exist in accurately calibrating the PBM and even within a set of specifically chosen case studies, collinearity between kinetic parameters causes identifiability issues (i.e., model outputs must be model input-sensitive and the influence of a change in one input parameter on the model output cannot be reversed through a change in another input parameter).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Modeling the Plantwide Implications of Struvite Loss from Sidestream Precipitation Reactors

et al. 2022

View full text Add to dashboard Cite

The combination of enhanced biological phosphorus removal (EBPR) with sidestream struvite precipitation is a synergistic treatment approach for P removal and recovery. However, periodic disruption events in crystallization reactors can cause fine struvite particle washout followed by P solubilization, leading to decreases in EBPR effluent quality, yet modeling tools do not exist to quantify plantwide impacts of struvite loss. To understand the impacts of struvite loss and dissolution on EBPR, this work first quantifies the dissolution rate of field-harvested struvite using the surface area-dependent shrinking object model and presents a novel particle population balance dissolution modeling tool for integration with a plantwide process simulator (SUMO). Analysis of time series P concentration data from dissolution experiments yields a rate constant of 1.14 mm min–1. Simulations of intra-plant phosphorus dynamics indicate that when struvite reactors operate with a high capture efficiency, the majority of influent orthophosphate can be captured through sidestream precipitation. In the event of struvite loss, large particles would not fully dissolve and are removed through sedimentation during primary clarification without significant disruption of EBPR. In contrast, the loss of 200 μm-sized struvite particles can lead to a difference in effluent phosphate of up to 0.8 mg P/L. Our results suggest that surface area-dependent models are essential to quantify the impacts of struvite loss and that reactor design should center on particle retention, rather than conversion of soluble P to struvite.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Modeling the Plantwide Implications of Struvite Loss from Sidestream Precipitation Reactors

et al. 2022

View full text Add to dashboard Cite

show abstract

“…In addition, struvite crystallization is favored by establishing the proper equilibrium and growth rate of crystals. Thus, the uncertainty can be reduced in the process, design, and operation of crystallization units [ 16 ].…”

Section: Introductionmentioning

confidence: 99%

Effects of Physicochemical Parameters on Struvite Crystallization Based on Kinetics

et al. 2022

IJERPH

View full text Add to dashboard Cite

The precipitation of struvite (MgNH4PO4·6H2O) is considered to be a promising method for the recovery of phosphate from wastewater. In this review, the kinetic models, which are commonly used to explain the process of struvite crystallization, are described. The mixed-suspension mixed-product removal (MSMPR) model is based on the population balance equation (the size-dependent growth model and the size-independent growth model). Thereafter, the first-order kinetic fitting model that aligned with concentration changes in the substrate is summarized. Finally, the several physical and chemical factors that affected the efficiency of struvite crystallization are determined. The supersaturation ratio, which is seen as the driving force of struvite crystallization, is the main factor that influences crystallization; however, it cannot be used in practical applications of engineering because it is indirectly associated with the following factors: pH, the molar ratio of Mg:N:P, and the interference of foreign impurities. In this study, we present conclusions that should be used to guide further research studies, and encourage the engineering practice of wastewater treatment with struvite precipitation.

show abstract

“…Nucleation of organic molecules begins with the self-recognition and assembly of solute molecules, resulting in a phase transition process and crystal formation . It thus controls many aspects of structure and property of a crystalline material such as polymorph, chirality, and size distribution of crystals . Understanding such a process will be beneficial for engineering new crystalline materials of desirable properties and for designing industrial processes for separation and purification.…”

Section: Introductionmentioning

confidence: 99%

“…1 It thus controls many aspects of structure and property of a crystalline material such as polymorph, 2 chirality, 3 and size distribution of crystals. 4 Understanding such a process will be beneficial for engineering new crystalline materials of desirable properties and for designing industrial processes for separation and purification. Although classical nucleation theory 1,5,6 has been put forward and developed over a century, the molecular mechanism of nucleation and the queries about which property or process controls the outcomes or rates of nucleation are still desired to be understood.…”

Section: Introductionmentioning

confidence: 99%

Understanding Nucleation Mechanism of Mefenamic Acid: An Examination of Relation between Pre-assembly Structure in Solution and Nucleation Kinetics

Han

Zhang

Liu

et al. 2021

Crystal Growth & Design

View full text Add to dashboard Cite

Crystal nucleation from solution plays a decisive role in the formation of crystalline materials, but its mechanism at the molecular level is still unclear. Structural similarity between self-assemblies in solution and crystal synthons suggested possible mechanisms of nucleation; however, the detailed role of these solute pre-assemblies on nucleation kinetics remains elusive. Herein, we examined the relation of solution chemistry with nucleation kinetics by an array of solution IR, 1D, and 2D NMR spectroscopy, density-functional theory calculations, and statistical probability distribution analyses of the measured induction time data with mefenamic acid (MFA) as the model compound. Depending on the solvent, MFA can form different hydrogen-bonded solution assemblies. Quantification of nucleation kinetics was performed by measuring 4400 sets of induction time data. Solution chemistry and nucleation kinetics collectively reveal that pre-assemblies in solution can serve as building units for crystal nucleation, but the difficulty of nucleation apparently correlates with the effective interfacial energy, not attachment frequency. The structure link may be obscured through nucleation kinetics driven by interfacial energy.

show abstract

Nucleation and crystal growth kinetic parameter optimization of a continuous Poiseuille flow struvite crystallizer using a discretized population balance and dynamic fluid model

Cited by 10 publications

References 25 publications

Modeling the Plantwide Implications of Struvite Loss from Sidestream Precipitation Reactors

Modeling the Plantwide Implications of Struvite Loss from Sidestream Precipitation Reactors

Effects of Physicochemical Parameters on Struvite Crystallization Based on Kinetics

Understanding Nucleation Mechanism of Mefenamic Acid: An Examination of Relation between Pre-assembly Structure in Solution and Nucleation Kinetics

Contact Info

Product

Resources

About