Calculation of multistage countercurrent separation processes-I. Multicomponent multistage rectification by differentiation with respect to an actual parameter

1973 ◽  
Vol 28 (8) ◽  
pp. 1555-1563 ◽  
Author(s):  
Jaroslav Jelínek ◽  
Vladimír Hlaváček ◽  
Milan Kubíček
Keyword(s):  
Separation Processes ◽  
Actual Parameter

A SEM/TEM examination of a ceramic membrane

1986 ◽  
Vol 44 ◽  
pp. 682-683
Author(s):  
C.E. Voegele-Kliewer ◽  
A.D. McMaster ◽  
G.W. Dirks
Keyword(s):  
Electron Microscopy ◽  
Gas Separation ◽  
Ceramic Membrane ◽  
Hydrogen Iodide ◽  
Separation Processes ◽  
Corning Glass ◽  
Gas Transport Properties ◽  
Porous Microstructure ◽  
Microscopy Techniques ◽  
The Relationship

Materials other than polymers, e.g. ceramic silicates, are currently being investigated for gas separation processes. The permeation characteristics of one such material, Vycor (Corning Glass #1370), have been reported for the separation of hydrogen from hydrogen iodide. This paper will describe the electron microscopy techniques applied to reveal the porous microstructure of a Vycor membrane. The application of these techniques has led to an increased understanding in the relationship between the substructure and the gas transport properties of this material.

SINTESIS DAN MODIFIKASI STRUKTUR DAN PORI MEMBRAN KITOSAN TERCROSSLINK UNTUK STERILISASI MEDIA PERTUMBUHAN BAKTERI

2019 ◽  
Vol 3 (2) ◽  
pp. 27
Author(s):  
Emma Savitri ◽  
Natalia Suseno ◽  
Tokok Adiarto
Keyword(s):  
Tensile Strength ◽  
Chitosan Solution ◽  
Curing Temperature ◽  
Growth Media ◽  
Optimum Conditions ◽  
Separation Processes ◽  
Crosslinking Process ◽  
Chitosan Membrane ◽  
Chitosan Membranes ◽  
Crosslinked Chitosan

Many mass-transfer applications have used chitosan membrane in separation processes. This research applied crosslinked chitosan membrane to sterillize bacterial growth media. Chitosan membranes having 79 % DD were produced by casting and drying chitosan solution. The images of the membrane were characterized by SEM and other characterizations such as permeability, permselectivity and tensile strength were investigated. The flux increased with longer submersion period but the rejection decreased. Otherwise, the flux decreased and rejection increased in line with an increase in curing temperature. Tensile strength increased with the increase of submersion period and curing temperature. The optimum conditions of crosslinking process are 2 hours of submersion periods and curing temperature at 90 oC.  It gives flux 5.8930 L/jam.m2, rejection 97.47 % and tensile strength 49640 kN/m2

Children show adult-like hippocampal pattern separation for familiar but not novel events

2020 ◽  
Author(s):  
Susan L. Benear ◽  
Elizabeth A. Horwath ◽  
Emily Cowan ◽  
M. Catalina Camacho ◽  
Chi Ngo ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Developmental Change ◽  
Pattern Separation ◽  
Developmental Changes ◽  
Similarity Analysis ◽  
Separation Processes ◽  
Parahippocampal Cortex ◽  
Pattern Similarity

The medial temporal lobe (MTL) undergoes critical developmental change throughout childhood, which aligns with developmental changes in episodic memory. We used representational similarity analysis to compare neural pattern similarity for children and adults in hippocampus and parahippocampal cortex during naturalistic viewing of clips from the same movie or different movies. Some movies were more familiar to participants than others. Neural pattern similarity was generally lower for clips from the same movie, indicating that related content taxes pattern separation-like processes. However, children showed this effect only for movies with which they were familiar, whereas adults showed the effect consistently. These data suggest that children need more exposures to stimuli in order to show mature pattern separation processes.

Fine liquor colour: how does it affect energy, capacity and sugar losses?

2015 ◽  
pp. 375-378
Author(s):  
Ahmed S. Vawda ◽  
Emmanuel M. Sarir ◽  
Carlos Andrés Donado
Keyword(s):  
Energy Capacity ◽  
Important Process ◽  
Separation Processes ◽  
Impurity Removal ◽  
Process Operations ◽  
Fuel Costs

Impurity removal by separation and crystallisation are the most important process operations in a refinery. This paper studies the main separation processes, namely clarification, decolourisation and crystallisation to demonstrate where poor separation contributes to excessive costs of processing. The results of various tests are analysed and conclusions are made for refiners to manage their chemical and fuel costs.

Dynamic simulation of sludge blanket movements in a full-scale rectangular sedimentation basin

1996 ◽  
Vol 33 (1) ◽  
pp. 89-99 ◽  
Author(s):  
F. Göhle ◽  
A. Finnson ◽  
B. Hultman
Keyword(s):  
Dynamic Simulation ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Full Scale ◽  
Simulation Studies ◽  
Separation Processes ◽  
Sedimentation Basin ◽  
Near Future ◽  
Sludge Concentration

Bromma sewage treatment plant in Stockholm is the second largest plant in Stockholm and will in the near future have requirements for nitrogen removal. This means that a higher sludge age must be used in the aeration basin. This may be accomplished by an increase of the sludge concentration up to values until the limiting solids flux is exceeded. Measurement of the sludge blanket level is a possibility for better control of the sedimentation basin. Different measurements were performed to evaluate the main factors influencing the level. Dynamic simulation studies were performed at Bromma sewage treatment plant in Stockholm of the sludge blanket level and the return sludge concentration in a full-scale sedimentation basin. The simulations were performed with the help of a Danish simulation package, EFOR (1992), in which both reactions in the aeration basin (mainly based on the IAWPRC model) and separation processes in the sedimentation basin (both clarification and thickening) can be studied. The thickening model is based on the solids flux theory and the Vesilind formula (1979). Different methods were compared for determination and use of characteristic parameters in the Vesilind formula.

Separation of Biologically Active Compounds by Membrane Operations

2017 ◽  
Vol 23 (2) ◽  
pp. 218-230 ◽  
Author(s):  
Xiaoying Zhu ◽  
Renbi Bai
Keyword(s):  
Energy Consumption ◽  
Bioactive Compounds ◽  
Membrane Fouling ◽  
Membrane Separation ◽  
Separation Efficiency ◽  
High Energy ◽  
Separation Processes ◽  
Membrane Processes ◽  
Separation Technology ◽  
Pressure Driven

Background: Bioactive compounds from various natural sources have been attracting more and more attention, owing to their broad diversity of functionalities and availabilities. However, many of the bioactive compounds often exist at an extremely low concentration in a mixture so that massive harvesting is needed to obtain sufficient amounts for their practical usage. Thus, effective fractionation or separation technologies are essential for the screening and production of the bioactive compound products. The applicatons of conventional processes such as extraction, distillation and lyophilisation, etc. may be tedious, have high energy consumption or cause denature or degradation of the bioactive compounds. Membrane separation processes operate at ambient temperature, without the need for heating and therefore with less energy consumption. The “cold” separation technology also prevents the possible degradation of the bioactive compounds. The separation process is mainly physical and both fractions (permeate and retentate) of the membrane processes may be recovered. Thus, using membrane separation technology is a promising approach to concentrate and separate bioactive compounds. Methods: A comprehensive survey of membrane operations used for the separation of bioactive compounds is conducted. The available and established membrane separation processes are introduced and reviewed. Results: The most frequently used membrane processes are the pressure driven ones, including microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF). They are applied either individually as a single sieve or in combination as an integrated membrane array to meet the different requirements in the separation of bioactive compounds. Other new membrane processes with multiple functions have also been developed and employed for the separation or fractionation of bioactive compounds. The hybrid electrodialysis (ED)-UF membrane process, for example has been used to provide a solution for the separation of biomolecules with similar molecular weights but different surface electrical properties. In contrast, the affinity membrane technology is shown to have the advantages of increasing the separation efficiency at low operational pressures through selectively adsorbing bioactive compounds during the filtration process. Conclusion: Individual membranes or membrane arrays are effectively used to separate bioactive compounds or achieve multiple fractionation of them with different molecule weights or sizes. Pressure driven membrane processes are highly efficient and widely used. Membrane fouling, especially irreversible organic and biological fouling, is the inevitable problem. Multifunctional membranes and affinity membranes provide the possibility of effectively separating bioactive compounds that are similar in sizes but different in other physical and chemical properties. Surface modification methods are of great potential to increase membrane separation efficiency as well as reduce the problem of membrane fouling. Developing membranes and optimizing the operational parameters specifically for the applications of separation of various bioactive compounds should be taken as an important part of ongoing or future membrane research in this field.

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