scholarly journals Population Balance and CFD Simulation of Particle Aggregation and Growth in a Continuous Confined Jet Mixer for Hydrothermal Synthesis of Nanocrystals

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 144
Author(s):  
Qing Yun Li ◽  
Xue Zhong Wang
Keyword(s):  
Particle Size ◽  
Cfd Simulation ◽  
Growth Models ◽  
Molecular Model ◽  
Population Balance ◽  
Surface Growth ◽  
Particle Aggregation ◽  
Balance Model ◽  
Crystallisation Process ◽  
Dynamics Models

Population balance and computational fluid dynamics models are built and integrated to carry out a simulation study of the reactive crystallisation process in a confined jet mixer (CJM) for the continuous flow synthesis of TiO2 nanoparticles at a supercritical water condition. In the population balance model, the crystal growth in size is modelled as being due to combined nanocrystal aggregation as well as surface growth. A free molecular model is used to predict the particle aggregation. The performance of the combined aggregation and surface growth models is compared with models that only consider surface growth as the only mechanism for particle size enlargement. It was found that the combined model gives a more accurate prediction of particle size distribution.

POPULATION BALANCE MODEL OF ICE CRYSTALS SIZE DISTRIBUTION DURING ICE SLURRY STORAGE

2014 ◽  
Vol 22 (02) ◽  
pp. 1440001 ◽  
Author(s):  
AIXIANG XU ◽  
ZHIQIANG LIU ◽  
TENGLEI ZHAO ◽  
XIAOXIAO WANG
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Crystal Size ◽  
Population Balance ◽  
Ice Crystals ◽  
Balance Model ◽  
Ice Slurry ◽  
Slurry Storage

Particle size distribution and number of ice crystals have a great influence on the flow and heat transfer performance of ice slurry. A population balance model (PBM) containing population and mass balances has been built to simulate numerically the development of ice particle size distribution during adiabatic ice slurry storage. The model assumes a homogeneously mixed and long-term storage tank in which the effect of breakage and aggregation between ice crystals was considered. For solving the population balance equations (PBEs) in the PBM, a semi-discrete finite volume scheme was applied. Finally, the effect of breakage and aggregation on development of ice particle size distribution was analyzed respectively. The results show that both breakage and aggregation are the two important effects on the particle size distribution and evolution of ice particle during storage, but they have opposite effect on the development of ice crystal size. In storage, breakage and aggregation have almost equivalent effect in the initial phase, but aggregation has dominant effect at last. The PBM results are in good agreement with experimental results by Pronk et al. [Effect of long-term ice slurry storage on crystal size distribution, 5th Workshop on Ice Slurries of the IIR (2002), pp. 151–160]. Therefore, the PBM presented in this paper is able to predict the development of particle size distribution during ice slurry storage.

CFD simulation of gas–liquid flow in a high-pressure bubble column with a modified population balance model

2018 ◽  
Vol 26 (6) ◽  
pp. 1350-1358 ◽  
Author(s):  
Bo Zhang ◽  
Lingtong Kong ◽  
Haibo Jin ◽  
Guangxiang He ◽  
Suohe Yang ◽  
...  
Keyword(s):  
High Pressure ◽  
Liquid Flow ◽  
Cfd Simulation ◽  
Bubble Column ◽  
Population Balance ◽  
Balance Model ◽  
Population Balance Model ◽  
Gas Liquid Flow

scholarly journals Milling Studies in an Impact Crusher I: Kinetics Modelling Based on Population Balance Modelling

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 470
Author(s):  
Ngonidzashe Chimwani ◽  
Murray M. Bwalya
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
Population Balance ◽  
Impeller Speed ◽  
Balance Model ◽  
Population Balance Model ◽  
Particle Sizes ◽  
Product Size ◽  
Kinetics Modelling ◽  
Vertical Impact

A number of experiments were conducted on a laboratory batch impact crusher to investigate the effects of particle size and impeller speed on grinding rate and product size distribution. The experiments involved feeding a fixed mass of particles through a funnel into the crusher up to four times, and monitoring the grinding achieved with each pass. The duration of each pass was approximately 20 s; thus, this amounted to a total time of 1 min and 20 s of grinding for four passes. The population balance model (PBM) was then used to describe the breakage process, and its effectiveness as a tool for describing the breakage process in the vertical impact crusher is assessed. It was observed that low impeller speeds require longer crushing time to break the particles significantly whilst for higher speeds, longer crushing time is not desirable as grinding rate sharply decreases as the crushing time increases, hence the process becomes inefficient. Results also showed that larger particle sizes require shorter breakage time whilst smaller feed particles require longer breakage time.

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