The electroosmotic dewatering allows accelerating the consolidation and increasing the dewatering of semi-solid materials and relies on the electroosmosis …Web
ادامه مطلبThe main mechanism of improving soft clay for electroosmosis is dewatering, which leads to consolidation and a consequent increase in strength of the soil until intergranular stresses are in equilibrium with the tension that develops in the pore water during electroosmosis. To enhance the effect of electroosmotic improvement, the …Web
ادامه مطلبVijh A.K., 1999, Electroosmotic dewatering (EOD) of clays and suspensions: Components of voltage in an electroosmotic cell, Drying Technology, 17(3), 565-574. Visvanathan C. and Ben Aïm R., 1989, Application of an electric field for the reduction of particle and colloidal membrane fouling in crossflow microfiltration, Separation Science and ...Web
ادامه مطلبThe electroosmotic dewatering efficiency under the constant electric current is compared with that under the constant voltage, concerning dewatering rate, water content in dewatered sludge and ...Web
ادامه مطلبThe variation of the total resistance was followed throughout the electro-dewatering for three different voltages (30 V, 40 V, 50 V). The results are reported in Fig. 3. They show that the voltage does not significantly impact the total resistance of the experimental system. Rapp increases highly at the end of the process when the filtrate ...Web
ادامه مطلبABSTRACT In our preliminary investigations, lab-scale and bench-scale electro-osmotic press dewatering units were tested with multiple test combinations and trials with various bio-materials to study the process parameters and to improve equipment designs. Effects of various pre-treatments and treatment combinations on the …Web
ادامه مطلبFiltration combined with an electric field (electrofiltration) enhances the filtration kinetics of aqueous suspensions. Although electrophoresis and electroosmosis largely contribute to electrofiltration behavior, side effects such as water electrolysis, heat production, and gravitational sedimentation of particles may be influential.Web
ادامه مطلبSince pressure dewatering is a popular technique to reduce the water content of solid waste, some works have combined electroosmotic drainage and pressure dewatering [44], [45]. Electroosmosis can be considered hydraulic flow caused by an electrical field [46], [47] .Web
ادامه مطلبThis sludge has to be dewatered mainly to reduce storage capacities and transport costs. Volume reduction is commonly achieved by mechanical dewatering processes due to its low energy requirement in comparison to thermal drying (Vaxelaire et al., 1999). However wastewater sludge is generally difficult to dewater.Web
ادامه مطلبThe results showed that electroosmotic dewatering under an applied electric potential of 1.0VDC/cm could increase the rate of dewatering and consolidation by an order of magnitude as compared to ...Web
ادامه مطلبOwing to the inherent inefficiency of dewatering equipment widely used today, the search for improved dewatering techniques has been pursued by the investigation of new innovative ideas. The main thrust of these investigations has been in electroosmotic dewatering which presents a novel approach in South Africa. The separation of the …Web
ادامه مطلبElectroosmotic dewatering under the condition of A.C. was experimentally investigated mainly in the region of low frequency below Hz for the electrode polarity reversals. In the dewatering process, the A.C. electric field could reduce the hindrance caused by the D.C, and final dewalered amount was increased more than that under the …Web
ادامه مطلبHowever, most research has concentrated on pressurised electroosmotic dewatering (PED), that is, the application of a DC electric field during the expression of formed cakes or porous media (Sprute and Kelsh, 1980, Lockhart, 1983a, Iwata et al., 1991, Barton et al., 1999; Weber and Stahl, 2002b).Web
ادامه مطلبIn the electroosmotic dewatering (EOD) of clays, suspensions and fines, a continuous or interrupted DC voltage, V, is applied between the anode and the cathode. …Web
ادامه مطلبMore recently, this equation was used by Dussour et al. (2000), Barton et al. (1999) and Iwata (2000). The other equations from Sørensen's model remain the same. 3. ... Electroosmotic dewatering of sludge under condition of constant voltage. Journal of Chemical Engineering of Japan, 11 (6) (1978), pp. 475-480.Web
ادامه مطلبFor efficient performance of electroosmotic dewatering, intermittent power application was used to reduce such excessive increase of the electrical contact resistance with the lapse of time ...Web
ادامه مطلبSince electroosmotic dewatering behaviour of iron oxide slimes has not been reported in the literature, EO was performed as a secondary dewatering process to assess the extent to which the iron oxide pulps could be consolidated, for a given pulp chemistry and dispersion conditions. ... Franks et al. (1999) ...Web
ادامه مطلبThe electroosmotic dewatering allows accelerating the consolidation and increasing the dewatering of semi-solid materials and relies on the electroosmosis (moving of ionized mobile liquid close to the particles surface due to the external electric field). ... Lite and Xiuqu, 1999, Xia et al., 2003, Al-Asheh et al., 2004, ...Web
ادامه مطلبThe results demonstrated that the injection of PAC solution is effective of increasing the soil dewatering, decreasing the energy consumption and shortening the electroosmosis duration. ... (1983) Electroosmotic dewatering of clays. II. Influence of salt, acid and flocculants. Colloids and Surfaces 6(3):239–251. ... (1999) Electrokinetic ...Web
ادامه مطلبThe pressure between the sludge and the electrode plate in the electroosmotic dewatering area of this equipment was generated by squeezing the sludge with a single screw pump, which was made use of the sludge semi fluidity. ... Dry. Technol., 17 (1999), pp. 539-554, 10.1080/07373939908917550. View in Scopus Google Scholar …Web
ادامه مطلبAbstract. Electro-osmosis is an established method of dewatering fine soils, sediments, and sludge (SSS). The efficiency of electro-osmotic treatment is controlled …Web
ادامه مطلبElectroosmotic dewatering of dredged sediments: bench-scale investigation. J. Environ. Manag. (2006) ... 2009), coal fly ash (Fang et al., 1999) and lime (Fang and Wong, 1999) could decrease the leaching risk of heavy metals and simultaneously improve the dewaterability by maintaining the sludge permeability during filter pressing; Liu et al ...Web
ادامه مطلبLi, L., Li, X., Uemura, K. and Tatsumi, E. (1999) Electro-osmotic dewatering of okara in different electric fields. Proceedings of The 99-th International Conference on …Web
ادامه مطلبElectroosmosis is a phenomenon describing water molecules being dragged along as solvation shell by the protons, which are conducted from anode to cathode. The electroosmotic coefficient Cdrag corresponds to the water molecules, transported by a single proton (see Eq. 3.9 ), (3.9) C drag = j drag F i.Web
ادامه مطلبThe average solid content between the electrodes during electroosmotic dewatering of a suspension of cellulose nanocrystals are shown in Fig. 2 for an applied electric field strength of 5 V/cm. The solid content of the cellulose nanocrystals increased from 2.3 to 15.3 wt%. Electroosmotic dewatering was thus used to remove more than …Web
ادامه مطلب1999; ABSTRACT Electrodewatering (EDW), the enhancement of conventional pressure filtration by an electric field, ... Electroosmotic dewatering of activated sludge is an important transport process playing a critical role in electroosmotic dewatering of sludge.Web
ادامه مطلب7.6.1.4 Electroosmotic dewatering. Electroosmotic dewatering is an alternative drying process, which merges conventional pressure integration with electrostatic effects. …Web
ادامه مطلبThe experiments of Yoshida et al. (1999), with different frequencies, showed that the best dewatering results were achieved by the lowest reversal frequency tested, 0.001 Hz, while frequencies higher than 0.01 Hz had worse results than the DC. The highest frequencies, 1 Hz and 50 Hz, showed no difference in dewatering. ... Electroosmotic ...Web
ادامه مطلبThe enhancement of conventional pressure consolidation by an electric field, known as electroosmotic dewatering (EOD), gave some encouraging results for sewage sludge (Friehmelt and Gidarakos, 1996, Barton et al., 1999, Mujumdar and Yoshida, 2008).Web
ادامه مطلبThe dewatering effect of the vacuum method is limited because the maximum negative pore ... (Dayao Bay). Based on the SL237 standard (1999), the basic properties of clay are shown in Table 1. The marine clay pH (measured in a suspension with a clay: water ratio equal to 1:5) was found at 7.72 and the grain-size distribution of marine clay in ...Web
ادامه مطلبInfluence of filter cloth on the cathode on the electroosmotic dewatering of activated sludge. Chin. J. Chem. Eng. (2010) W.A. Barton et al. The electrodewatering of sewage sludges. Dry. Technol. (1999) G. Chen et al. Sludge dewatering and drying. Dry. Technol. (2002) View more references.Web
ادامه مطلبThis article presents an efficient approach for the analysis of combined electroosmotic dewatering (EOD) and mechanical expression (ME) using the Terzaghi-Voigt combined model by considering creep deformation of the material. The EOD-ME process enhances dewatering because it combines the advantage of electroosmosis …Web
ادامه مطلب7.6.1.4 Electroosmotic dewatering. Electroosmotic dewatering is an alternative drying process, which merges conventional pressure integration with electrostatic effects. Compared to traditional thermal processes, this method allows the reduction of energy consumption up to two-thirds. ... 1999), i.e. about 1.5 % of the energy demand of ...Web
ادامه مطلبNowadays wastewater treatment plants are producing huge amount of sludge. The water content of the traditionally dewatered sludge, resulting from drying beds, centrifuges, vacuum filters, screw press filters and pressure filters, remains a critical factor affecting the choice of transportation vehicles, transportation costs, and suitability of …Web
ادامه مطلبnecrosis of the tumor tissue is given in which the electro-osmotic dewatering at the anode and excess water accumulation at the cathode are the paramount effects, together with the associated pH changes. # 1999 Kluwer Academic Publishers 1. Introduction Following the pioneering studies of Nordenstro¨m on theWeb
ادامه مطلبElectroosmotic drainage consists of applying a low electric potential to dewater a porous medium. Casagrande, 1947, Casagrande, 1949, Casagrande, 1952 first employed this technique to consolidated clay soils as a simple and efficient way to accelerate dewatering in soils with low hydraulic conductivity.Web
ادامه مطلبPressurised electroosmotic dewatering (PED) is usually implemented in classical filters with the electrodes making a direct contact with the material or the filter cloths. Thus, electrolysis products generated at the electrodes (gas, ions) tend to accumulate in the solid/liquid mixture being dewatered. ... 1999): (2) ψ = ψ 0 + ψ s + ψ Ω, ...Web
ادامه مطلبThis paper describes the role of pressurized electroosmotic dewatering (EOD) in a filter cycle. A laboratory-scale filter-press was used to filter a highly conductive silica suspension under constant pressure, followed by washing and mechanical precompression of the filter cake and finally by pressurized EOD at constant electric …Web
ادامه مطلبThe U.S. Department of Energy's Office of Scientific and Technical InformationWeb
ادامه مطلبThe unidirectional migration of electroosmotic flow under direct current electric field has remained an issue of previous studies such as seriously uneven strength and difficult drainage collecting, which primarily limited the practical engineering applications of electroosmosis method. Innovative cyclic and progressive electroosmosis method …Web
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