Optimization of Kinetic Model for High Rate Algal Pond Design

The results of experimental and mathematical modelling of simultaneous processes of organic and nitrogen impurities removal in an industrial Carrousel wastewater treatment plant are presented. The hydrodynamic regime measurements in the full-scale Carrousel system have led to the conclusion that at least three hydrodynamic models such as tank-in-series, ideally mixing reactor with aerobic and anoxic volume and completely mixing reactor with an intermittent aeration, are suitable to describe the dynamic behaviour of this bioreactor. The tank-in-series and the intermittently aerated completely mixing equipments were used in lab-scale modelling of the Carrousel plants. Various kinetic models and a statistical approach were applied to the evaluation of laboratory and full-scale data. The simplified kinetic model proved to be convenient for the process control purposes due to the significant computational time reduction in model parameters determination in comparision to tank-in-series hydrodynamic modelling. Also, the statistical model is very suitable approximation of the processes carried out in the Carrousel system. The completely mixing bioreactor with intermittent aeration is advantageous for experimental simulation of simultaneous nitrification and denitrification processes performed in high-rate recycled activated sludge systems. The influence of wastewater substances on oxygen transport rate is implicitly incorporated through aerobic and anoxic ‘switching functions’ evaluated based on oxygen profile data monitored in the bioreactor when applying the modified IAWPRC kinetic model.

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A coupled RTD and mixed-order kinetic model to predict high rate algal pond wastewater treatment under different operational conditions: Performance assessment and sizing application

Biochemical Engineering Journal ◽

10.1016/j.bej.2020.107709 ◽

2020 ◽

Vol 162 ◽

pp. 107709

Author(s):

Le Anh Pham ◽

Julien Laurent ◽

Paul Bois ◽

Adrien Wanko

Keyword(s):

Wastewater Treatment ◽

Kinetic Model ◽

Performance Assessment ◽

High Rate ◽

Order Kinetic ◽

Operational Conditions ◽

Mixed Order ◽

Order Kinetic Model

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Structure of Palladium Single-Crystal Films Prepared by Flash Evaporation onto (001) NaCl Substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069272 ◽

1970 ◽

Vol 28 ◽

pp. 456-457

Author(s):

L. E. Murr ◽

G. Wong

Keyword(s):

Single Crystal ◽

High Vacuum ◽

Ultra High Vacuum ◽

High Rate ◽

Flash Evaporation ◽

Optimum Load ◽

Single Crystal Films ◽

Crystal Films ◽

A Current

Palladium single-crystal films have been prepared by Matthews in ultra-high vacuum by evaporation onto (001) NaCl substrates cleaved in-situ, and maintained at ∼ 350° C. Murr has also produced large-grained and single-crystal Pd films by high-rate evaporation onto (001) NaCl air-cleaved substrates at 350°C. In the present work, very large (∼ 3cm2), continuous single-crystal films of Pd have been prepared by flash evaporation onto air-cleaved (001) NaCl substrates at temperatures at or below 250°C. Evaporation rates estimated to be ≧ 2000 Å/sec, were obtained by effectively short-circuiting 1 mil tungsten evaporation boats in a self-regulating system which maintained an optimum load current of approximately 90 amperes; corresponding to a current density through the boat of ∼ 4 × 104 amperes/cm2.

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Rapid Freezing of Freeze-Etch Specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600003275 ◽

1980 ◽

Vol 38 ◽

pp. 752-755

Author(s):

A. Elgsaeter ◽

T. Espevik ◽

G. Kopstad

Keyword(s):

Low Temperature ◽

Metal Surface ◽

Relative Velocity ◽

Thermal Contact ◽

High Rate ◽

Rapid Freezing ◽

Temperature Decrease ◽

Freeze Etching

The importance of a high rate of temperature decrease (“rapid freezing”) when freezing specimens for freeze-etching has long been recognized1. The two basic methods for achieving rapid freezing are: 1) dropping the specimen onto a metal surface at low temperature, 2) bringing the specimen instantaneously into thermal contact with a liquid at low temperature and subsequently maintaining a high relative velocity between the liquid and the specimen. Over the last couple of years the first method has received strong renewed interest, particularily as the result of a series of important studies by Heuser and coworkers 2,3. In this paper we will compare these two freezing methods theoretically and experimentally.

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