PDF Publication Title:
Text from PDF Page: 020
layer formation and concentration polarisation. In addition, the presence of DC leads to concentration polarisation in the internal pores even when the external diffusion layers are not present [147]. Finally the blank resistance to be subtracted in order to separate the resistance of the membrane from that of the solution can be relatively very high for low concentration, thus affecting the accuracy of the method. As an alternative to DC-based methods, AC-based measurements can be performed adopting the Electrical Impedance Spectroscopy (EIS) method, able to distinguish among the contributions due to Ohmic effects, electric double layer and diffusion boundary layer and, thus, to estimate the pure membrane resistance [75, 142, 148, 149]. On the other hand, EIS is the most complex methodology, as it requires the identification and implementation of an “electrical model” fully describing all phenomena involved, in order to properly interpret the experimental data and convert them into the desired information. 3.4 Fouling and electrodialysis with polarity reversal (EDR) Although ED is not generally affected by fouling and scaling phenomena as much as other desalination processes such as RO [150], IEMs fouling can still be a limiting factor for maintaining good process performances. In particular, this phenomenon can significantly enhance membrane resistance and pressure drops along the channel and, in some cases, even reduce membrane permselectivity [151]. I-V curves are often used to characterise membrane fouling, though this method does not provide information on the properties of fouling layers. EIS has been proposed as a supplementary investigation method in order to capture more details on interfacial layers [152]. Three main classes of fouling compounds can be identified: scalants, colloidal particles and organic materials [153]. Scaling is one of the most important problems in desalination, especially when the feed water is rich in low-solubility salts such as CaCO3 and CaSO4. The most common methods for reducing it include the use of lower recovery rate, the adjustment of pH and cleaning procedures with citric acid or EDTA [153]. In addition, the possibility of treating the concentrate stream (i.e. the one with highest scaling potential) of a batch ED unit by magnetic or ultrasonic field has been reported [154]. In particular, the magnetic field was applied to a part of the feeding line, while an ultrasonic bath was used as the concentrate tank. Interestingly, the last method not only results in a scaling reduction but also in an improvement of ions transport. 20PDF Image | Electrodialysis for water desalination
PDF Search Title:
Electrodialysis for water desalinationOriginal File Name Searched:
Review_ED-self-archived.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 |