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Guijun Xian - One of the best experts on this subject based on the ideXlab platform.
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long term service evaluation of a pultruded carbon glass hybrid rod exposed to elevated temperature Hydraulic Pressure and fatigue load coupling
International Journal of Fatigue, 2020Co-Authors: Xiaoli Yin, Yancong Liu, Rui Guo, Guijun XianAbstract:Abstract In the present paper, a pultruded glass fiber shell (GFS) and carbon fiber core (CFC) hybrid rod (HFRP) with the diameter of 19 mm was exposed in an underground oil well. The exposure environment of elevated temperature (T), Hydraulic Pressure (P) and fatigue load (L) coupling was realized, including two exposure conditions, T = 25 °C, P = 0.5 MPa, Lmax = 70 kN and T = 90 °C, P = 18 MPa, Lmax = 50 kN. The long-term evaluation of mechanical, thermal properties and microstructure of HFRP rods was conducted to reveal the evolution mechanism during exposure. It can be observed that the short beam shear strength and interface shear strength of HFRP rods decreased obviously with the exposure time. Higher exposed temperature and Hydraulic Pressure aggravated the degradation through accelerating the diffusion of water molecule into HFRP rods. In contrast, higher fatigue stress level played an insignificant effect owing to the low difference of fatigue stress level. During exposure, the diffusion of water molecule caused the hydrolysis and plasticizing of resin and increased the pore volume content (~3%) in the rod. Plenty of bound water (>90%) formed and weaken the Van der Waals force and hydrogen bond between fiber and resin, finally leading to debonding of fiber/resin interface, especially for the higher exposed temperature and Hydraulic Pressure. The fatigue tests of HFRP rods immersed at 60 °C/20 MPa for one year in the laboratory were conducted to simulate the fatigue behavior exposed in the underground oil well. Furthermore, the residual fatigue life of HFRP rods was predicted to be more than 15.55 years. When the designed fatigue life of HFRP rods in actual exposure was 10 years, the maximum applied fatigue load was predicted to be 144.7 kN.
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influence of immersion in water under Hydraulic Pressure on the interfacial shear strength of a unidirectional carbon glass hybrid rod
Polymer Testing, 2018Co-Authors: Guijun XianAbstract:Abstract A pultruded unidirectional carbon/glass (core/shell) hybrid rod of 19 mm in diameter was developed for marine applications. To understand the long-term evolution of the mechanical properties of the rod in service, a Pressure chamber device with adjustable Hydraulic Pressure and a self-designed interfacial shear strength (ISS) setup were developed. Immersion in water was performed at 20 °C, 40 °C, and 60 °C without Hydraulic Pressure or at 60 °C with a Hydraulic Pressure of 20 MPa for one year. Dynamic mechanical analysis (DMA) was conducted to analyse the thermal properties of the hybrid rod. Post curing, indicated by the increase in the glass transition temperature (Tg), was pronounced during immersion. ISS of the shell, core and shell/core interfaces was sensitive to water immersion and decreased after 360 days. A linear decrease of ISS with the exposure temperature was observed. The Hydraulic Pressure had a positive effect on ISS, especially for the GFRP shell. The evaluation of the long-term behaviour indicated that ISS will decrease to a stable level of 74.8% for glass fibre/resin, 57.8% for carbon fibre/resin and 69.9% for the interface between the carbon fibre core and the glass fibre shell.
Menachem Elimelech - One of the best experts on this subject based on the ideXlab platform.
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thin film composite membrane compaction in high Pressure reverse osmosis
Journal of Membrane Science, 2020Co-Authors: Douglas M Davenport, Cody L Ritt, Rhea Verbeke, Marcel Dickmann, Werner Egger, Ivo F J Vankelecom, Menachem ElimelechAbstract:Abstract Membrane deformation under an applied Hydraulic Pressure, often termed compaction, is observed in almost all Pressure-driven membrane processes. Most notably, compaction decreases water permeability in conventional reverse osmosis (RO) and is expected to critically hinder high-Pressure reverse osmosis (HPRO) for hypersaline brine desalination. In this work, we demonstrated that compaction decreases the water permeability of commercial RO membranes from 2.0 L m−2 h−1 bar−1 at 70 bar applied Hydraulic Pressure to 1.3 L m−2 h−1 bar−1 at 150 bar. The morphological effects of compaction were primarily associated with changes in the support layer, where a ~60% decrease in cross-sectional thickness is observed following compaction at 150 bar Hydraulic Pressure. In contrast, positron annihilation lifetime spectroscopy demonstrates that the selective layer does not compact irreversibly. The mechanism that drives compaction was found to be the difference in Hydraulic Pressure across the interface of the selective and support layers. We further found that compaction can reduce the support layer surface porosity by up to ~95%. This decreased porosity is identified as the cause for compaction-induced water permeability decline, while the intrinsic permeability of the selective layer is not influenced by compaction. As such, we conclude that compaction of the support layer has an inextricable impact on composite membrane performance. Finally, we propose recommendations for developing compaction-resistant membranes that can maintain high water permeability, and thus good desalination performance, in high-Pressure membrane applications, such as HPRO.
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Effect of Hydraulic Pressure and membrane orientation on water flux and reverse solute flux in Pressure assisted osmosis
Journal of Membrane Science, 2014Co-Authors: Yoontaek Oh, Seockheon Lee, Menachem Elimelech, Sangho Lee, Seungkwan HongAbstract:Forward osmosis (FO) is an emerging technology that has received much global interest due to its potential applications in wastewater reclamation and seawater desalination. One of the major challenges to overcome is the detrimental effects of concentration polarization (CP), which reduce the effective osmotic Pressure driving force and thus decrease productivity of the FO process. In this study, Pressure assisted osmosis (PAO) was investigated as a method to increase the effective driving force and water flux by combining an osmotic Pressure driving force with an additional Hydraulic Pressure. Experiments were carried out to examine the efficiency of the PAO process using a bench-scale setup specially designed to prevent membrane deformation under the applied Hydraulic Pressure. Results showed that PAO water flux increased with increasing the applied Hydraulic Pressure in FO mode (i.e., active layer facing the feed solution). The measured water fluxes were in good agreement with predictions based on a model developed to describe the water flux in PAO operation. However, the PAO water flux was lower than model predictions in PRO mode (i.e., active layer facing the draw solution). This observation is attributed to the spacer 'shadow effect' and the resulting reduction in the effective membrane area by the spacers. The results also showed that reverse solute flux decreased with increasing the applied Hydraulic Pressure in both FO and PRO modes. Although applying Hydraulic Pressure to FO increases energy consumption, the higher water flux in PAO reduces the number of membrane modules for the FO process. In addition, control of the driving force is easier in PAO than FO, leading to flexibility in system design and operation. Based on these results, a possible combination of FO and RO system with PAO was proposed for allowing higher energy efficiency in seawater desalination. © 2014.
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raising the bar increased Hydraulic Pressure allows unprecedented high power densities in Pressure retarded osmosis
Environmental Science and Technology Letters, 2014Co-Authors: Anthony P. Straub, Menachem ElimelechAbstract:Pressure-retarded osmosis (PRO) has the potential to generate sustainable energy from salinity gradients. PRO is typically considered for operation with river water and seawater, but a far greater energy of mixing can be harnessed from hypersaline solutions. This study investigates the power density that can be obtained in PRO from such concentrated solutions. Thin-film composite membranes with an embedded woven mesh were supported by tricot fabric feed spacers in a specially designed crossflow cell to maximize the operating Pressure of the system, reaching a stable applied Hydraulic Pressure of 48 bar (700 psi) for more than 10 h. Operation at this increased Hydraulic Pressure allowed unprecedented power densities, up to 60 W/m2 with a 3 M (180 g/L) NaCl draw solution. Experimental power densities demonstrate reasonable agreement with power densities modeled using measured membrane properties, indicating high-Pressure operation does not drastically alter membrane performance. Our findings exhibit the pro...
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adverse impact of feed channel spacers on the performance of Pressure retarded osmosis
Environmental Science & Technology, 2012Co-Authors: Menachem ElimelechAbstract:This article analyzes the influence of feed channel spacers on the performance of Pressure retarded osmosis (PRO). Unlike forward osmosis (FO), an important feature of PRO is the application of Hydraulic Pressure on the high salinity (draw solution) side to retard the permeating flow for energy conversion. We report the first observation of membrane deformation under the action of the high Hydraulic Pressure on the feed channel spacer and the resulting impact on membrane performance. Because of this observation, reverse osmosis and FO tests that are commonly used for measuring membrane transport properties (water and salt permeability coefficients, A and B, respectively) and the structural parameter (S) can no longer be considered appropriate for use in PRO analysis. To accurately predict the water flux as a function of applied Hydraulic Pressure difference and the resulting power density in PRO, we introduced a new experimental protocol that accounts for membrane deformation in a spacer-filled channel to...
Marco Tallini - One of the best experts on this subject based on the ideXlab platform.
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A record of changes in the Gran Sasso groundwater before, during and after the 2016 Amatrice earthquake, central Italy
Scientific Reports, 2018Co-Authors: Gaetano De Luca, Giuseppe Di Carlo, Marco TalliniAbstract:We performed continuous recordings (May 2015 – January 2017) of Hydraulic Pressure and electrical conductivity of groundwater in the 190 m-long horizontal S13 borehole drilled next to the deep underground laboratories of Gran Sasso ( LNGS-INFN ), located in the core of the Gran Sasso carbonate aquifer (central Italy) at a distance of about 39 km south-eastward from the 24 August 2016 Amatrice earthquake (6.0 M_w) epicenter. Using a 3-channel, 24-bit ADC we achieved a sampling rate of groundwater physical properties up to 50 Hz for each channel. We focused on the analysis of data recorded before, during and after the Amatrice earthquake, describing and discussing in detail the evidence for significant Hydraulic Pressure and electrical conductivity anomalies recorded before the main shock. We identified unambiguous signals in the Hydraulic Pressure data starting on 19 August, i.e. five days before the 24 August mainshock. A more careful analysis allowed us to detect the inception of a weak change up to 40 days before the Amatrice earthquake and a significant variation in the electrical conductivity data about 60 days before. The data revealed highly dynamic aquifer behaviour associated with the uprising of geogas probably related to the preparation stage of the Amatrice earthquake.
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Hydraulic Pressure variations of groundwater in the gran sasso underground laboratory during amatrice earthquake of august 24th 2016
Annals of Geophysics, 2016Co-Authors: Gaetano De Luca, Giuseppe Di Carlo, Marco TalliniAbstract:Since May 2015, Hydraulic Pressure, temperature and electrical conductivity of groundwater are in continuos recording near the deep underground laboratories of Gran Sasso of INFN. We used the S13 borehole that have Pressure varying in the range of 24-28 bar during the year; these values mean that we have at least 300 m of water table above. The sampling of these parameters was brought until to 50 Hz using a 3 channels 24-bit ADC. During the period May 2015 – September 2016 (17 months) we detected Hydraulic Pressure signals from 12 earthquakes at different surface distances (from 12.000 to 30 km) and different magnitudes (from 8.3 to 4.3 Mw). For the Amatrice mainshock, we present, as first results, the hydroseismograph recorded at the S13 Hydraulic Pressure device compared to the time history recorded at GIGS station located both in the deep core of the Gran Sasso chain.
Gaetan Blandin - One of the best experts on this subject based on the ideXlab platform.
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impact of Hydraulic Pressure on membrane deformation and trace organic contaminants rejection in Pressure assisted osmosis pao
Process Safety and Environmental Protection, 2016Co-Authors: Gaetan Blandin, Pierre Leclech, Harm Vervoort, Arnout Dhaese, Klaas Schoutteten, Julie Vanden Bussche, Lynn Vanhaecke, Darli T Myat, Arne VerliefdeAbstract:Abstract This study provides for the first time an extensive comparison of trace organic contaminants (TrOCs) rejection by commercial cellulose tri-acetate (CTA) and thin film composite (TFC) forward osmosis (FO) membranes from HTI and Porifera operated under Pressure assisted osmosis (PAO) conditions. Commercial TFC membranes allowed for higher water permeabilities, higher selectivities and higher water fluxes in FO and PAO operation, compared to the HTI CTA benchmark. As for HTI CTA, TFC membranes suffered from deformation due to the Hydraulic Pressure applied in the PAO process. However, not only deformation by stretching of the active layer, but also compaction of the support layer was observed, reducing internal concentration polarisation (ICP) and allowing for flux enhancement. In FO operation, the TFC membranes demonstrated a high rejection (>80% for HTI TFC and >90% for Porifera) of the whole range of tested TrOCs due to steric hindrance. It was also noticed that, being more negatively charged, the TFC membranes allowed for very high rejection of negatively charged compounds, but lower rejection of positively charged molecules, as a consequence of electrostatic interactions. In PAO operation, a general decrease of TrOCs rejection was observed. This could possibly be a consequence of decreasing selectivity (due to membrane deformation), increased TrOCs external concentration polarisation and/or lower reverse salt diffusion (less hindrance of forward TrOCs diffusion).
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validation of assisted forward osmosis afo process impact of Hydraulic Pressure
Journal of Membrane Science, 2013Co-Authors: Gaetan Blandin, Arne Verliefde, Chuyang Y Tang, Amy E Childress, Pierre LeclechAbstract:Abstract The use of forward osmosis (FO) is of growing interest for water desalination, due to its potential energy savings. However, its industrial implementation is still limited by its actual performance limitation in water permeation and reverse salt diffusion, due to membrane properties. Assisted forward osmosis (AFO) is a new concept, aiming at pressurising the feed solution to enhance water permeation through synergising osmotic and Hydraulic driving forces. This paper presents the impact of Hydraulic Pressure on the FO membrane properties and the overall performances of the system in order to validate the interest of AFO. When 6 bar was applied on the feed side of the process, the membrane water permeability ( A ) was observed to double, mainly due to the membrane deformation against the spacers. Under those conditions, the additional driving force provided resulted in 70% increase in permeation flux, despite the more severe concentration polarisation. More interestingly, the observed reverse salt diffusion was significantly lower than expected by the solution diffusion model, confirming the interest of AFO in tackling current limitations of FO technology. This study also revealed the relative limitations of the current methodology used for the determination of membrane solute and water permeabilities, which currently fail to consider membrane deformation that could arise in Pressure retarded osmosis and AFO systems.
Gaetano De Luca - One of the best experts on this subject based on the ideXlab platform.
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A record of changes in the Gran Sasso groundwater before, during and after the 2016 Amatrice earthquake, central Italy
Scientific Reports, 2018Co-Authors: Gaetano De Luca, Giuseppe Di Carlo, Marco TalliniAbstract:We performed continuous recordings (May 2015 – January 2017) of Hydraulic Pressure and electrical conductivity of groundwater in the 190 m-long horizontal S13 borehole drilled next to the deep underground laboratories of Gran Sasso ( LNGS-INFN ), located in the core of the Gran Sasso carbonate aquifer (central Italy) at a distance of about 39 km south-eastward from the 24 August 2016 Amatrice earthquake (6.0 M_w) epicenter. Using a 3-channel, 24-bit ADC we achieved a sampling rate of groundwater physical properties up to 50 Hz for each channel. We focused on the analysis of data recorded before, during and after the Amatrice earthquake, describing and discussing in detail the evidence for significant Hydraulic Pressure and electrical conductivity anomalies recorded before the main shock. We identified unambiguous signals in the Hydraulic Pressure data starting on 19 August, i.e. five days before the 24 August mainshock. A more careful analysis allowed us to detect the inception of a weak change up to 40 days before the Amatrice earthquake and a significant variation in the electrical conductivity data about 60 days before. The data revealed highly dynamic aquifer behaviour associated with the uprising of geogas probably related to the preparation stage of the Amatrice earthquake.
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Hydraulic Pressure variations of groundwater in the gran sasso underground laboratory during amatrice earthquake of august 24th 2016
Annals of Geophysics, 2016Co-Authors: Gaetano De Luca, Giuseppe Di Carlo, Marco TalliniAbstract:Since May 2015, Hydraulic Pressure, temperature and electrical conductivity of groundwater are in continuos recording near the deep underground laboratories of Gran Sasso of INFN. We used the S13 borehole that have Pressure varying in the range of 24-28 bar during the year; these values mean that we have at least 300 m of water table above. The sampling of these parameters was brought until to 50 Hz using a 3 channels 24-bit ADC. During the period May 2015 – September 2016 (17 months) we detected Hydraulic Pressure signals from 12 earthquakes at different surface distances (from 12.000 to 30 km) and different magnitudes (from 8.3 to 4.3 Mw). For the Amatrice mainshock, we present, as first results, the hydroseismograph recorded at the S13 Hydraulic Pressure device compared to the time history recorded at GIGS station located both in the deep core of the Gran Sasso chain.
