PDF Publication Title:
Text from PDF Page: 032
Membranes 2020, 10, 221 32 of 72 than for continuous current condition. As mentioned before in Section 3.4.2, the duration of PEF process is a crucial point. 4.2.2. EDBM-PEF PEF has been tested for the first time on bipolar membrane by Mikhaylin et al. in 2016 for the precipitation of milk casein to decrease protein fouling and scaling [88]. Since 2016, the PEF during EDBM process has been tested to increase the efficiency of the process in terms of scaling/fouling elimination [88,106], process technical feasibility [106], energy efficiency [122], migration improvement [122] and production of ingredients with new properties [137]. Pelletier et al. [122] reported that the recovery of citric and malic acids, from cranberry juice was about 15–18% faster using PEFs and the energy consumption decreased by 7–10% for 1 s/1 s and 2 s/2 s conditions in comparison to continuous current conditions. Furthermore, the concentration of quinic acid and phenolic compounds remained constant in the feed warranting a preserved quality of the juice. EDBM-PEF used at optimal 2 s/0.5 s PEF conditions [112], demonstrated substantial improvement in limiting scaling during casein production. It maintained a satisfactory permselectivity for CEMs, thus preventing the leakage of hydroxide anions from the base compartment [88]. Electroacidification of black liquor from pulp and paper industry to pH 9.7 by EDBM-PEF was found optimal for 6 s/24 s conditions due to the 80% current efficiency and 2.6 kWh/kg NaOH energy consumption obtained [106]. As a comparison, in DC mode, fouling was observed leading to a 45% current efficiency and 4.6 kWh/kg NaOH power consumption. 4.2.3. EDR-PEF or pEDR Taking into consideration the recent reports on ECVs, and given the challenges still present in PEF electrodialysis, a new technology was recently proposed by Gonzalez-Vogel and Rojas by the application of asymmetric bipolar (reverse polarity) pulses [138]. Indeed, ED intensification was introduced by application of asymmetric pulses of reverse polarity and very short pulses (10 to 100 μs) at high frequencies (from 100 to 4000 Hz) were tested, modulating the amplitude of the pulses to adjust energy consumption. Under such conditions, the LCD increased by up to 1.6 times compared to conventional ED. Additionally, the pH was kept stable during the whole desalination process, decreasing the occurrence of detrimental effects caused by pH changes. Desalination performance under overlimiting conditions exhibited improved mass transfer, while decreasing the demineralization time by 43%. However, the energy consumption under overlimiting current conditions increased by around 56% or 14% compared to conventional ED at sub-limiting or overlimiting current regimes, respectively. The authors also observed that while transport of ions in PEF mode is dominated by concentration gradients, in pEDR the transport would mainly occur by migration. Hence, by favouring migration, the transport of counter and co-ions during pEDR is promoted by the electric field towards the ion depleted layer, accelerating the refilling process and inducing the formation of electroconvective vortices after re-application of forward voltages. According to the authors, this new desalination strategy is expected to decrease the capital costs of ED plants given the prospects of operation under reduced equipment sizes [138]. The higher energy consumption appeared clearly as a drawback of pEDR, however, they proposed to use cheap energy such as solar power for small plants to allow water demineralization in an intensive way. 4.3. Electrodialysis Metathesis (EDM) The metathesis reaction consists in the exchange of anions (A, A’) and cations (C, C’) between two salts resulting in their conversion in different salts: CA + C’A’ => CA’ + C’A (19)PDF Image | Electrodialytic Processes
PDF Search Title:
Electrodialytic ProcessesOriginal File Name Searched:
membranes-10-00221.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |