PDF Publication Title:
Text from PDF Page: 011
Membranes 2020, 10, 347 11 of 15 3.3. Energy Consumption Figure 8a–d shows the energy consumption and current density required to achieve a certain percentage of desalination as calculated from the performed experiments (considering only the electrical component and not the pumping). The energy density needed to reach 90% (or close to 90% in the case of fireclay) desalination was notably lower for NaCl with both Siltep 11 and foamed fireclay, as expected due to the size and charge of SO42−. After reaching desalination of 99%, the energy requirements for additional desalination rise steeply. Further increments in applied current and voltage also caused heating of the unit, mainly apparent in the electrode streams, in which the temperature increased up to 40 ◦C while the unit got warm to the touch. Lowering the energy demand for production of very diluted (>99%) water could be possible by splitting the process into multiple stages in series, a method that is used in commonly employed desalination technologies and was tested for the first time with SED by [18]. Despite the suboptimal choice of porous material (especially regarding the combination of surface charge and choice of membranes) and the energy losses due to heat generation, the energy consumption is comparable to experiments performed on glass frit and in much smaller volumes by [20]. This observation is interesting from the scale-up point of view. The larger cross-sectional area of the frit used in our unit decreases energy consumption as, according to Ohm’s law, the power P is inversely proportional to the cross-sectional area (P = I2R, where resistivity R ~ L/A; L being the length of the resistive material and A the cross-sectional area). Comparison between the L/A ratio of the porous material of our unit (L/A = 10/5000 mm−1 = 0.002 mm−1) and the glass frit in early SED unit by [20] (L/A = 2.7/200 mm−1 = 0.0135 mm−1), unveils the reason behind similar energy density even at two orders of magnitude higher flow rates, which drives the energy requirements up (the current I is proportional to flow rate Q for the same dimensionless current according to Equation (1) and, therefore, E = P/Q ~ QL/A [18]). Although the power consumption was still significant, this study was not primarily focused on its reduction, and the main components to affect it remain largely unoptimized. 3.4. Porous Media Choice and Shape The theoretical and experimental work published previously suggests the usage of porous materials with close to 1 μm pore size to sustain deionization shocks in the OLC region [4,13,16,20]. Larger pores (approximately >10 μm) may lead to convective mixing that may interrupt the shock formation and produce instabilities inside the porous material. However, such a small pore size (around 1 μm) is inevitably connected with high hydrodynamic resistivity. Therefore, low volume flow rates or increasing energy demand for pumping seem to be the downsides of the previously described SED devices [21]. As the purpose of this scale-up was to increase the production of freshwater, it was necessary to consider the usage of materials with higher solution throughput, possibly even with lower effectivity in the beginning. Therefore, two types of porous ceramics with different pore sizes that were both more than one order of magnitude larger compared to pores of the glass frit used in [4,16–20] (and different enough one from the other) were chosen for this study. The solution throughput was also related to the increased dimensions of the porous material, especially in the direction of the solution flow, which only added to the hydrodynamic resistivity of the material. On the other hand, this increase was made with an idea of a longer flow trajectory that would provide more space and therefore require lower currents for the shock to propagate, as also [18] suggests and discusses. For further scale-up, widening the porous medium (and the whole unit) could also be beneficial in order to increase the cross-sectional area and the functional membrane area. The size, shape, and morphology significantly affected power consumption.PDF Image | Desalination Performance Assessment Anion-Exchange Membranes
PDF Search Title:
Desalination Performance Assessment Anion-Exchange MembranesOriginal File Name Searched:
membranes-10-00347.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 (Standard Web Page)