scholarly journals THE EFFECT OF OPERATING CONDITIONS ON CRITICAL FLUX AND REVERSIBLE FOULING IN MEMBRANE FILTRATION USING GAS SPARGING TECHNIQUE

2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Harunsyah Harunsyah ◽  
Nik Meriam Sulaiman
Keyword(s):  
Flow Rate ◽  
Membrane Filtration ◽  
Membrane System ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Feed Flow Rate ◽  
Permeate Flux ◽  
Critical Flux ◽  
Gas Sparging ◽  
Cake Layer

Gas sparging method utilizing injection of nitrogen gas was employed during the ultrafiltration of the natural rubber effluent (latex serum). The objective of this research was to investigate the effect of gas sparging on the critical flux and the observed reversible cake layer resistance during the ultrafiltration of skim latex serum. Experiments were conducted using a 100 kDa MWCO tubular membrane (PCI Membrane System) mounted vertically. The effect of operating parameters, such as feed flow rate, concentration and transmembrane pressure were investigated. The results showed that when the feed flow rate was increased, the permeate was correspondingly increased and the reversible cake resistance decreased. In this research a feed flow rate of 1400 ml/min and transmembrane pressure of 13.00 psig resulted in the maximum total permeate flux of 70.80 L/m2h. Results from this study obtained so far showed that the use of gas sparging has been able to increase total permeate flux between 8.3% and 145.3% compared to non-gas sparged condition. Critical flux occurrence was increased to 82.63% above the value obtained for non-sparged condition and applied transmembrane pressure can be reduced to 2.4% of the non-gas sparged condition.Keyword: skim latex serum, reversible fouling, gas sparged, critical flux

scholarly journals Multi-objective optimization of microfiltration of baker’s yeast using genetic algorithm

2017 ◽  
pp. 211-220 ◽  
Author(s):  
Natasa Lukic ◽  
Marija Bozin-Dakic ◽  
Jovana Grahovac ◽  
Jelena Dodic ◽  
Aleksandar Jokic
Keyword(s):  
Genetic Algorithm ◽  
Genetic Algorithms ◽  
Energy Consumption ◽  
Flow Rate ◽  
Transmembrane Pressure ◽  
Feed Flow Rate ◽  
Multi Objective Optimization ◽  
Permeate Flux ◽  
Multi Objective ◽  
Reduction Of Energy Consumption

This paper presents a multi-objective optimization model by applying genetic algorithm in order to search for optimal operating parameters of microfiltration of baker?s yeast in the presence of static mixer as a turbulence promoter. The operating variables were the suspension concentration, transmembrane pressure, and feed flow rate. Two conflicting objective functions, maximizing the permeate flux and maximizing the reduction of energy consumption, were considered. This multi-objective optimization problem was solved by using the elitist non-dominated sorting genetic algorithm in the Matlab R2015b software. The Pareto fronts along with the process decision variables correspondding to the optimal solutions were obtained. It was found that lower suspension concentrations (2-4.5 g/L), feed flow rate in the range 109-127 L/h, and transmembrane pressure of 1 bar were the optimal process parameters which yielded maximum permeate flux (177-191 L/(m2h)) and maximum reduction of energy consumption (44-50%). Finally, the results were compared with the previously published results obtained by applying desirability function approach. Given that genetic algorithms have generated multiple solutions in a single optimization run, the study proved that genetic algorithms are preferable to classical optimization methods.

Experimental and Modelling of Aqueous Radioactive Waste Treatment by Ultrafiltration

2018 ◽  
Vol 69 (5) ◽  
pp. 1149-1151
Author(s):  
Laura Ruxandra Zicman ◽  
Elena Neacsu ◽  
Felicia Nicoleta Dragolici ◽  
Catalin Ciobanu ◽  
Gheorghe Dogaru ◽  
...  
Keyword(s):  
Flow Rate ◽  
Suspended Solids ◽  
Waste Treatment ◽  
Operating Pressure ◽  
Feed Flow Rate ◽  
Permeate Flux ◽  
Independent Variables ◽  
Opposite Trend ◽  
Process Factors ◽  
Volumetric Flux

Ultrafiltration of untreated and pretreated aqueous radioactive wastes was conducted using a spiral-wound polysulphonamide membrane. The influence of process factors on its performances was experimental studied and predicted. Permeate volumetric flux and permeate total suspended solids (TSS) were measured at different values of feed flow rate (7 and 10 m3/h), operating pressure (0.1-0.4 MPa), and feed TSS (15 and 60 mg/L). Permeate flux (42-200 L/(m2�h)) increased with feed flow rate and operating pressure as well as it decreased with an increase in feed TSS, whereas permeate TSS (0.1-33.2 mg/L) exhibited an opposite trend. A 23 factorial plan was used to establish correlations between dependent and independent variables of ultrafiltration process.

Filtration resistance induced by ammonia oxidizers accumulating on the rotating membrane disk

1998 ◽  
Vol 38 (4-5) ◽  
pp. 443-452
Author(s):  
Katsuki Kimura ◽  
Yoshimasa Watanabe ◽  
Naoki Ohkuma
Keyword(s):  
Membrane Filtration ◽  
Extracellular Polymeric Substances ◽  
Drinking Water Treatment ◽  
Treatment Method ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Ammonia Oxidizers ◽  
Filtration Resistance ◽  
Rotating Membrane Disk ◽  
Membrane Disk

Membrane filtration and oxidation of ammonia were simultaneously performed by using a rotating membrane disk module. Nitrification performance, composition of the accumulated cakes on the membrane and the filtration resistances were investigated under five different operating conditions. The filtration resistance due to the accumulated cake on the membrane was found to be dominant in this treatment method, compared to the resistance due to the micropore plugging or irreversible adherence. The cake consisted mainly of iron, humic substances and bacteria. The possibility that extracellular polymeric substances were related to the cake resistance was also shown. The composition of the cake depended on the length and the condition of operation. Accumulation of ammonia oxidizers caused by oxidation of low concentrations of ammonia (less than 1 mg/l) did not increase transmembrane pressure significantly. Therefore, the application of this treatment method for drinking water treatment is feasible. Filtration resistance due to the micropore plugging or irreversible adherence to the membrane was caused by organic substances.

scholarly journals Data-driven Modelling of Microfiltration Process with Embedded Static Mixer for Steepwater from Corn Starch Industry

2017 ◽  
Author(s):  
Laslo Šereš ◽  
Ljubica Dokić ◽  
Bojana Ikonić ◽  
Dragana Šoronja-Simović ◽  
Miljana Djordjević ◽  
...  
Keyword(s):  
Corn Starch ◽  
Desirability Function ◽  
Specific Energy Consumption ◽  
Cross Flow ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Static Mixer ◽  
Permeate Flux ◽  
Experimental Conditions ◽  
Starch Industry

Cross-flow microfiltration using ceramic tubular membrane was applied for treatment of steepwater from corn starch industry. Experiments are conducted according to the faced centered central composite design at three different transmembrane pressures (1, 2 and 3 bar) and cross-flow velocities (100, 150 and 200 L/h) with and without the usage of Kenics static mixer. For examination of the influence of the selected operating conditions at which usage of the static mixer is justified, a response surface methodology and desirability function approach were used. Obtained results showed improvement in the average permeate flux by using Kenics static mixer for 211 % to 269 % depending on experimental conditions when compared to the system without the static mixer. As a result of optimization, the best results considering flux improvement as well as reduction of specific energy consumption were obtained at low transmembrane pressure and lower feed cross-flow rates.

scholarly journals Membrane Fouling Controlled by Adjustment of Biological Treatment Parameters in Step-Aerating MBR

Membranes ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 553
Author(s):  
Dimitra C. Banti ◽  
Manassis Mitrakas ◽  
Petros Samaras
Keyword(s):  
Membrane Fouling ◽  
Membrane Filtration ◽  
Municipal Wastewater ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Aeration Tank ◽  
Filamentous Bacteria ◽  
Membrane Performance ◽  
Low Concentrations ◽  
Fouling Reduction

A promising solution for membrane fouling reduction in membrane bioreactors (MBRs) could be the adjustment of operating parameters of the MBR, such as hydraulic retention time (HRT), food/microorganisms (F/M) loading and dissolved oxygen (DO) concentration, aiming to modify the sludge morphology to the direction of improvement of the membrane filtration. In this work, these parameters were investigated in a step-aerating pilot MBR that treated municipal wastewater, in order to control the filamentous population. When F/M loading in the first aeration tank (AT1) was ≤0.65 ± 0.2 g COD/g MLSS/d at 20 ± 3 °C, DO = 2.5 ± 0.1 mg/L and HRT = 1.6 h, the filamentous bacteria were controlled effectively at a moderate filament index of 1.5–3. The moderate population of filamentous bacteria improved the membrane performance, leading to low transmembrane pressure (TMP) at values ≤2 kPa for a great period, while at the control MBR the TMP gradually increased reaching 14 kPa. Soluble microbial products (SMP), were also maintained at low concentrations, contributing additionally to the reduction of ΤΜP. Finally, the step-aerating MBR process and the selected imposed operating conditions of HRT, F/M and DO improved the MBR performance in terms of fouling control, facilitating its future wider application.

Concentration and Desalination of Protein Derived from Tuna Cooking Juice by Nanofiltration

2013 ◽  
Vol 65 (4) ◽  
Author(s):  
Muhammadameen Hajihama ◽  
Wirote Youravong
Keyword(s):  
Membrane Filtration ◽  
Protein Concentration ◽  
Protein Hydrolysate ◽  
Salt Content ◽  
Cross Flow ◽  
Transmembrane Pressure ◽  
Permeate Flux ◽  
Batch Mode ◽  
Additional Process ◽  
Canning Industry

Tuna cooking juice is a co-product of tuna canning industry. It riches in protein, currently used for production of feed meal as well as protein hydrolysate. The finish products are usually in the form of concentrate, produced by evaporation process. However, evaporation is energy consumable process and the salt content level of the concentrate is often over the standard, thus required additional process for lowering salt content e.g. crystallization. The use of membrane technology, therefore, is of interest, since it required less energy and footprint compared with evaporation and is also able to reduce salt content of the concentrate. The aim of this study were to employ and select the membrane filtration process, and optimize the operating condition for protein concentration and desalination of tuna cooking juice. The results indicated that nanofiltration (NF) was more suitable than the ultrafiltration (UF) process, regarding the ability in protein recovery and desalination. The NF performance was evaluated in terms of permeation flux and protein and salt retentions. The protein and salt rejections of NF were 96 % and 5 %, respectively. The permeate flux(J) increased as transmembrane pressure (TMP) or cross flow rate (CFR) increased and the highest flux was obtained at TMP of 10 bar and CFR of 800 L/h. Operating with batch mode, the permeate flux was found to decrease as protein concentration increased, and at volume concentration factor about 4, the protein concentration  about 10% while salt removal was aproximately 70 % of the initial value. This work clearly showed that NF was successfully employed for concentration and desalination of protein derived from tuna cooking juice.

KNT-artificial neural network model for flux prediction of ultrafiltration membrane producing drinking water

2004 ◽  
Vol 50 (8) ◽  
pp. 103-110 ◽  
Author(s):  
H.K. Oh ◽  
M.J. Yu ◽  
E.M. Gwon ◽  
J.Y. Koo ◽  
S.G. Kim ◽  
...  
Keyword(s):  
Neural Network ◽  
Experimental Data ◽  
Artificial Neural Network ◽  
Correlation Coefficient ◽  
Network Model ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Feed Water ◽  
Permeate Flux ◽  
Artificial Neural

This paper describes the prediction of flux behavior in an ultrafiltration (UF) membrane system using a Kalman neuro training (KNT) network model. The experimental data was obtained from operating a pilot plant of hollow fiber UF membrane with groundwater for 7 months. The network was trained using operating conditions such as inlet pressure, filtration duration, and feed water quality parameters including turbidity, temperature and UV254. Pre-processing of raw data allowed the normalized input data to be used in sigmoid activation functions. A neural network architecture was structured by modifying the number of hidden layers, neurons and learning iterations. The structure of KNT-neural network with 3 layers and 5 neurons allowed a good prediction of permeate flux by 0.997 of correlation coefficient during the learning phase. Also the validity of the designed model was evaluated with other experimental data not used during the training phase and nonlinear flux behavior was accurately estimated with 0.999 of correlation coefficient and a lower error of prediction in the testing phase. This good flux prediction can provide preliminary criteria in membrane design and set up the proper cleaning cycle in membrane operation. The KNT-artificial neural network is also expected to predict the variation of transmembrane pressure during filtration cycles and can be applied to automation and control of full scale treatment plants.

scholarly journals Flux intensification during microfiltration of distillery stillage using a kenics static mixer

2017 ◽  
pp. 285-293
Author(s):  
Vesna Vasic ◽  
Aleksandar Jokic ◽  
Marina Sciban ◽  
Jelena Prodanovic ◽  
Jelena Dodic ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Flow Rate ◽  
Specific Energy Consumption ◽  
Point Of View ◽  
Transmembrane Pressure ◽  
Feed Flow Rate ◽  
Static Mixer ◽  
Economic Point ◽  
Mathematical Presentation

The present work studies the effect of operating parameters (pH, feed flow rate, and transmembrane pressure) on microfiltration of distillery stillage. Experiments were conducted in the presence of a Kenics static mixer as a turbulence promoter, and its influence on the flux improvement and specific energy consumption was examined. Response surface methodology was used to investigate the effect of selected factors on microfiltration performances. The results showed that response surface methodology is an appropriate model for mathematical presentation of the process. It was found that the use of a static mixer is justified at the feed flow rates higher than 100 L/h. In contrast, the use of a static mixer at low values of feed flow rate and transmembrane pressure has no justification from an economic point of view.

scholarly journals Microfiltration with periodic gas backwashing as an alternative technique for increasing permeate flux

2018 ◽  
Vol 72 (2) ◽  
pp. 59-68
Author(s):  
Tijana Urosevic ◽  
Dragan Povrenovic ◽  
Predrag Vukosavljevic ◽  
Ivan Urosevic
Keyword(s):  
Steady State ◽  
Flow Rate ◽  
Driving Force ◽  
Fruit Juice ◽  
Cross Flow ◽  
Fruit Juices ◽  
Transmembrane Pressure ◽  
Permeate Flux ◽  
Cross Flow Filtration ◽  
Flow Filtration

In this paper, the influence of operating parameters (transmembrane pressure, temperature, the flow rate of retentate) on the cross - flow microfiltration of synthetic fruit juice and periodic backwashing with air was examined. In the experiments, the Kerasep W5 ceramic membrane with a separation limit of 0.2 ?m was used. The results of experiments in which different transmembrane pressures were used showed that stationary fluxes, at stationary conditions, after 60 minutes, have similar values. So, it can be concluded that the value of the driving force is irrelevant at steady state conditions. However, until the steady state conditions are established, a positive effect of the increase in the driving force is opposed to the negative effect of the increased polarization resistance, as a result of the driving force increase. Thus, the optimal transmembrane pressure was determined amounting to 2 bars. The optimum temperature of the process of clearing the fruit juices by microfiltration is reported as 55?C. Higher temperatures are not used due to a degrading effect on the chemical composition of the juice and a long microfiltration process. With an increase in the temperature of retentate from 22?C to 55?C, the permeate flux increased up to 60%. Increasing the flow rate of retentate reduces the thickness of the formed layer on the surface of the membrane. Due to limitations of the experimental setup and the large surface area of the membrane, the specific velocity of the retentate was low, so that the effects of cross-flow filtration were absent. The use of cross-flow filtration is one of the main requirements for increasing permeate flux, but in the present case it was in overall insufficient, so we have applied periodic air backwashing for improving fruit juice flux during membrane clarification. With this technique, the deposited layer on the membrane is lifted and the permeate flux is maintained at high levels preventing establishment of the steady state in the low flux zone. The time spent for the periodic backwashing was low as compared to the benefits of the increase in the collected permeate quantity. In all experiments with periodic backwashing with air, the collected permeate quantity is higher for up to 72.5 % as compared to experiments without backwashing. By increasing the backwashing duration, the flux increase is up to 5 %, which can be significant for microfiltration at industrial scale. Therefore, this technique is certainly recommended for microfiltration in the production of fruit juices.

Sign in / Sign up

Export Citation Format

Share Document