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Sample records for contact membrane distillation

  1. Polyazole hollow fiber membranes for direct contact membrane distillation

    KAUST Repository

    Maab, Husnul; Alsaadi, Ahmad Salem; Francis, Lijo; Livazovic, Sara; Ghaffour, NorEddine; Amy, Gary L.; Nunes, Suzana Pereira

    2013-01-01

    Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

  2. Polyazole hollow fiber membranes for direct contact membrane distillation

    KAUST Repository

    Maab, Husnul

    2013-08-07

    Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

  3. Electrical Thermal Network for Direct Contact Membrane Distillation Modeling and Analysis

    KAUST Repository

    Karam, Ayman M.

    2015-02-04

    Membrane distillation is an emerging water distillation technology that offers several advantages compared to conventional water desalination processes. Although progress has been made to model and understand the physics of the process, many studies are based on steady-state assumptions or are computationally not appropriate for real time control. This paper presents the derivation of a novel dynamical model, based on analogy between electrical and thermal systems, for direct contact membrane distillation (DCMD). The proposed model captures the dynamics of temperature distribution and distilled water flux. To demonstrate the adequacy of the proposed model, validation with transient and steady-state experimental data is presented.

  4. Transport phenomena and fouling in vacuum enhanced direct contact membrane distillation: Experimental and modelling

    KAUST Repository

    Naidu, Gayathri

    2016-08-27

    The application of vacuum to direct contact membrane distillation (vacuum enhanced direct contact membrane distillation, V-DCMD) removed condensable gasses and reduced partial pressure in the membrane pores, achieving 37.6% higher flux than DCMD at the same feed temperature. Transfer mechanism and temperature distribution profile in V-DCMD were studied. The empirical flux decline (EFD) model represented fouling profiles of V-DCMD. In a continuous V-DCMD operation with moderate temperature (55 degrees C) and permeate pressure (300 mbar) for treating wastewater ROC, a flux of 16.0 +/- 0.3 L/m(2) h and high quality distillate were achieved with water flushing, showing the suitability of V-DCMD for ROC treatment. (C) 2016 Elsevier B.V. All rights reserved.

  5. Transport phenomena and fouling in vacuum enhanced direct contact membrane distillation: Experimental and modelling

    KAUST Repository

    Naidu, Gayathri; Shim, Wang Geun; Jeong, Sanghyun; Choi, YoungKwon; Ghaffour, NorEddine; Vigneswaran, Saravanamuthu

    2016-01-01

    The application of vacuum to direct contact membrane distillation (vacuum enhanced direct contact membrane distillation, V-DCMD) removed condensable gasses and reduced partial pressure in the membrane pores, achieving 37.6% higher flux than DCMD at the same feed temperature. Transfer mechanism and temperature distribution profile in V-DCMD were studied. The empirical flux decline (EFD) model represented fouling profiles of V-DCMD. In a continuous V-DCMD operation with moderate temperature (55 degrees C) and permeate pressure (300 mbar) for treating wastewater ROC, a flux of 16.0 +/- 0.3 L/m(2) h and high quality distillate were achieved with water flushing, showing the suitability of V-DCMD for ROC treatment. (C) 2016 Elsevier B.V. All rights reserved.

  6. Fabrication of bioinspired composite nanofiber membranes with robust superhydrophobicity for direct contact membrane distillation.

    Science.gov (United States)

    Liao, Yuan; Wang, Rong; Fane, Anthony G

    2014-06-03

    The practical application of membrane distillation (MD) for water purification is hindered by the absence of desirable membranes that can fulfill the special requirements of the MD process. Compared to the membranes fabricated by other methods, nanofiber membranes produced by electrospinning are of great interest due to their high porosity, low tortuosity, large surface pore size, and high surface hydrophobicity. However, the stable performance of the nanofiber membranes in the MD process is still unsatisfactory. Inspired by the unique structure of the lotus leaf, this study aimed to develop a strategy to construct superhydrophobic composite nanofiber membranes with robust superhydrophobicity and high porosity suitable for use in MD. The newly developed membrane consists of a superhydrophobic silica-PVDF composite selective skin formed on a polyvinylidene fluoride (PVDF) porous nanofiber scaffold via electrospinning. This fabrication method could be easily scaled up due to its simple preparation procedures. The effects of silica diameter and concentration on membrane contact angle, sliding angle, and MD performance were investigated thoroughly. For the first time, the direct contact membrane distillation (DCMD) tests demonstrate that the newly developed membranes are able to present stable high performance over 50 h of testing time, and the superhydrophobic selective layer exhibits excellent durability in ultrasonic treatment and a continuous DCMD test. It is believed that this novel design strategy has great potential for MD membrane fabrication.

  7. Renewable water: Direct contact membrane distillation coupled with solar ponds

    International Nuclear Information System (INIS)

    Suárez, Francisco; Ruskowitz, Jeffrey A.; Tyler, Scott W.; Childress, Amy E.

    2015-01-01

    Highlights: • Experimental investigation of direct contact membrane distillation driven by solar ponds. • The DCMD/SGSP system treats ∼6 times the water flow treated by an AGMD/SGSP system. • Half of the energy extracted from the SGSP was used to transport water across the membrane. • Reducing heat losses through the DCMD/SGSP system would yield higher water fluxes. - Abstract: Desalination powered by renewable energy sources is an attractive solution to address the worldwide water-shortage problem without contributing significant to greenhouse gas emissions. A promising system for renewable energy desalination is the utilization of low-temperature direct contact membrane distillation (DCMD) driven by a thermal solar energy system, such as a salt-gradient solar pond (SGSP). This investigation presents the first experimental study of fresh water production in a coupled DCMD/SGSP system. The objectives of this work are to determine the experimental fresh water production rates and the energetic requirements of the different components of the system. From the laboratory results, it was found that the coupled DCMD/SGSP system treats approximately six times the water flow treated by a similar system that consisted of an air–gap membrane distillation unit driven by an SGSP. In terms of the energetic requirements, approximately 70% of the heat extracted from the SGSP was utilized to drive thermal desalination and the rest was lost in different locations of the system. In the membrane module, only half of the useful heat was actually used to transport water across the membrane and the remainder was lost by conduction in the membrane. It was also found that by reducing heat losses throughout the system would yield higher water fluxes, pointing out the need to improve the efficiency throughout the DCMD/SGSP coupled system. Therefore, further investigation of membrane properties, insulation of the system, or optimal design of the solar pond must be addressed in

  8. Polyoxadiazole hollow fibers for produced water treatment by direct contact membrane distillation

    KAUST Repository

    Xu, Jingli; Srivatsa Bettahalli, N.M.; Chisca, Stefan; Khalid, Mohammed Khalil; Ghaffour, NorEddine; Vilagines, Ré gis; Nunes, Suzana Pereira

    2018-01-01

    Treatment of produced water in the petroleum industry has been a challenge worldwide. In this study, we evaluated the use of direct contact membrane distillation (DCMD) for this purpose, removing oil and dissolved elements and supplying clean water

  9. Direct contact membrane distillation: Capability to desalt raw water

    Directory of Open Access Journals (Sweden)

    Ali Boubakri

    2017-05-01

    Full Text Available In this work, the potentialities of membrane distillation to desalt raw waters were investigated. The experiments were performed on a direct contact membrane distillation (DCMD unit using a flat sheet polypropylene (PP membrane with a low pore size of 0.064 μm. The effect of relevant operating parameters such as transmembrane temperature difference, hydrodynamic conditions and ionic strength on permeate flux and conductivity was studied. The results indicated that a permeate flux increases with increasing transmembrane temperature difference and Reynolds number, and slightly decreases with increasing ionic strength. The permeate flux reached 4.24 L/m2 h at a temperature difference of 60 °C and Reynolds number of 3740 and ionic strength of 8.56 × 10−2 M. DCMD process using PP with low pore size membrane present a very low salt passage through the membrane which was not affected by feed concentration. DCMD process has been applied during a long period to desalt raw water without any pretreatment. For brackish water, the variation of permeate flux and conductivity were slightly changed as function of operating time. For seawater, the permeate flux decreased slightly and the permeate conductivity increased sharply in which a simple pretreatment step is recommended to ameliorate the performance of DCMD process.

  10. A Model of Direct Contact Membrane Distillation of Black Currant Juice

    DEFF Research Database (Denmark)

    Jensen, Morten Busch; Christensen, Knud Villy; Andrésen, René

    2011-01-01

    A numerical model to describe a direct contact membrane distillation proces has been developed. Said model is based on the Dusty Gas model and shell mass and energy balances over a tubular membrane module.  "The solution is applicable to laminar, incompressible and continuous flow in shell......-side spacing of tubular-type unit."  Turtuosity and porosity are characteristics of the membrane in use and have been estimated base don eksperimental studies on destillation of pure water. The fitted model shows a good fit to experimental data obtained by destillation of black currant juice....

  11. Direct Contact Membrane Distillation of Dairy Process Streams

    Directory of Open Access Journals (Sweden)

    Mike Weeks

    2011-01-01

    Full Text Available Membrane distillation (MD was applied for the concentration of a range of dairy streams, such as whole milk, skim milk and whey. MD of a pure lactose solution was also investigated. Direct contact MD (DCMD mode experiments were carried out in continuous concentration mode, keeping the warm feed/retentate and cold permeate stream temperatures at 54 °C and 5 °C respectively. Performance in terms of flux and retention was assessed. The flux was found to decrease with an increase of dry-matter concentration in the feed. Retention of dissolved solids was found to be close to 100% and independent of the dry-matter concentration in the feed. Fourier Transform Infrared Spectroscopy (FTIR of the fouled membranes confirms organics being present in the fouling layer.

  12. Electrical equivalent thermal network for direct contact membrane distillation modeling and analysis

    KAUST Repository

    Karam, Ayman M.

    2016-09-19

    Membrane distillation (MD) is an emerging water desalination technology that offers several advantages compared to conventional desalination methods. Although progress has been made to model the physics of the process, there are two common limitations of existing models. Firstly, many of the models are based on the steady-state analysis of the process and secondly, some of the models are based on partial differential equations, which when discretized introduce many states which are not accessible in practice. This paper presents the derivation of a novel dynamic model, based on the analogy between electrical and thermal systems, for direct contact membrane distillation (DCMD). An analogous electrical thermal network is constructed and its elements are parameterized such that the response of the network models the DCMD process. The proposed model captures the spatial and temporal responses of the temperature distribution along the flow direction and is able to accurately predict the distilled water flux output. To demonstrate the adequacy of the proposed model, validation with time varying and steady-state experimental data is presented. (C) 2016 Elsevier Ltd. All rights reserved.

  13. Dynamic solar-powered multi-stage direct contact membrane distillation system: Concept design, modeling and simulation

    KAUST Repository

    Lee, Jung Gil; Kim, Woo-Seung; Choi, June-Seok; Ghaffour, NorEddine; Kim, Young-Deuk

    2017-01-01

    This paper presents a theoretical analysis of the monthly average daily and hourly performances of a solar-powered multi-stage direct contact membrane distillation (SMDCMD) system with an energy recovery scheme and dynamic operating system. Mid

  14. Effect of feed flow pattern on the distribution of permeate fluxes in desalination by direct contact membrane distillation

    KAUST Repository

    Soukane, Sofiane; Naceur, Mohamed W.; Francis, Lijo; Alsaadi, Ahmad Salem; Ghaffour, NorEddine

    2017-01-01

    The current study aims to highlight the effect of flow pattern on the variations of permeate fluxes over the membrane surface during desalination in a direct contact membrane distillation (DCMD) flat module. To do so, a three dimensional (3D

  15. Fouling in Membrane Distillation, Osmotic Distillation and Osmotic Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Mourad Laqbaqbi

    2017-03-01

    Full Text Available Various membrane separation processes are being used for seawater desalination and treatment of wastewaters in order to deal with the worldwide water shortage problem. Different types of membranes of distinct morphologies, structures and physico-chemical characteristics are employed. Among the considered membrane technologies, membrane distillation (MD, osmotic distillation (OD and osmotic membrane distillation (OMD use porous and hydrophobic membranes for production of distilled water and/or concentration of wastewaters for recovery and recycling of valuable compounds. However, the efficiency of these technologies is hampered by fouling phenomena. This refers to the accumulation of organic/inorganic deposits including biological matter on the membrane surface and/or in the membrane pores. Fouling in MD, OD and OMD differs from that observed in electric and pressure-driven membrane processes such electrodialysis (ED, membrane capacitive deionization (MCD, reverse osmosis (RO, nanofiltration (NF, ultrafiltration (UF, microfiltration (MF, etc. Other than pore blockage, fouling in MD, OD and OMD increases the risk of membrane pores wetting and reduces therefore the quantity and quality of the produced water or the concentration efficiency of the process. This review deals with the observed fouling phenomena in MD, OD and OMD. It highlights different detected fouling types (organic fouling, inorganic fouling and biofouling, fouling characterization techniques as well as various methods of fouling reduction including pretreatment, membrane modification, membrane cleaning and antiscalants application.

  16. Treatment of Simulated Coalbed Methane Produced Water Using Direct Contact Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Dong-Wan Cho

    2016-05-01

    Full Text Available Expolitation of coalbed methane (CBM involves production of a massive amount saline water that needs to be properly managed for environmental protection. In this study, direct contact membrane distillation (DCMD was utilized for treatment of CBM-produced water to remove saline components in the water. Simulated CBM waters containing varying concentrations of NaCl (1, 20, and 500 mM and NaHCO3 (1 and 25 mM were used as feed solutions under two transmembrane temperatures (Δ40 and 60 °C. In short-term distillation (~360 min, DCMD systems showed good performance with nearly 100% removal of salts for all solutes concentrations at both temperatures. The permeate flux increased with the feed temperature, but at a given temperature, it remained fairly stable throughout the whole operation. A gradual decline in permeate flux was observed at Δ60 °C at high NaHCO3 concentration (25 mM. In long-term distillation (5400 min, the presence of 25 mM NaHCO3 further decreased the flux to 25%–35% of the initial value toward the end of the operation, likely due to membrane fouling by deposition of Ca-carbonate minerals on the pore openings. Furthermore, pore wetting by the scalants occurred at the end of the experiment, and it increased the distillate conducitivity to 110 µS·cm−1. The precipitates formed on the surface were dominantly CaCO3 crystals, identified as aragonite.

  17. Flux Enhancement in Membrane Distillation Using Nanofiber Membranes

    Directory of Open Access Journals (Sweden)

    T. Jiříček

    2016-01-01

    Full Text Available Membrane distillation (MD is an emerging separation technology, whose largest application potential lies in the desalination of highly concentrated solutions, which are out of the scope of reverse osmosis. Despite many attractive features, this technology is still awaiting large industrial application. The main reason is the lack of commercially available membranes with fluxes comparable to reverse osmosis. MD is a thermal separation process driven by a partial vapour pressure difference. Flux, distillate purity, and thermal efficiency are always in conflict, all three being strictly connected with pore size, membrane hydrophobicity, and thickness. The world has not seen the ideal membrane yet, but nanofibers may offer a solution to these contradictory requirements. Membranes of electrospun PVDF were tested under various conditions on a direct contact (DCMD unit, in order to determine the optimum conditions for maximum flux. In addition, their performance was compared to commonly available PTFE, PE, and PES membranes. It was confirmed that thinner membranes have higher fluxes and a lower distillate purity and also higher energy losses via conduction across the membrane. As both mass and heat transfer are connected, it is best to develop new membranes with a target application in mind, for the specific membrane module and operational conditions.

  18. Dual-Bioinspired Design for Constructing Membranes with Superhydrophobicity for Direct Contact Membrane Distillation.

    Science.gov (United States)

    Zhu, Zhigao; Liu, Yuanren; Hou, Haoqing; Shi, Wenxin; Qu, Fangshu; Cui, Fuyi; Wang, Wei

    2018-03-06

    Water flux and durability are the two critical parameters that are closely associated with the practical application of membrane distillation (MD). Herein, we report a facile approach to fabricate superhydrophobic polyimide nanofibrous membranes (PI NFMs) with hierarchical structures, interconnected pores, and high porosity, which was derived from the electrospinning, dual-bioinspired design, and fluorination processes. Bioinspired adhesive based on polydopamine /polyethylenimine (PDA/PEI) composite was first linked onto membrane substrates and then assembled lotus leaf hierarchical structure by binding the negatively charged silica nanoparticles (SiO 2 NPs) via electrostatic attraction. The resultant superhydrophobic PI NFMs exhibit a water contact angle of 152°, robust hot water resistance of 85 °C, and high water entry pressure of 42 kPa. Moreover, the membrane with omniphobicity presents high water flux over 31 L m -2 h -1 and high salts rejection of ∼100% as well as robust durability for treating high salinity wastewater containing typical low surface tension and dissolved contaminants (Δ T = 40 °C). Significantly, the novel dual-bioinspired method can be used as a universal tool to modify various materials with hierarchical structures, which is expected to provide more effective alternative membranes for MD and even for other selective wetting separation fields.

  19. Preparation of novel poly(vinylidene fluoride)/TiO2 photocatalysis membranes for use in direct contact membrane distillation

    Science.gov (United States)

    Li, Yukun; Dong, Shuying; Zhu, Liang

    2018-03-01

    Immobilization of TiO2 is a potential approach to obtain photocatalytic membranes that could eliminate concentration polarization in sewage disposal for direct contact membrane distillation (DCMD) process. A simple non-solvent-induced phase separation (NIPS) method was proposed to prepare poly(vinylidene fluoride) (PVDF) membrane, and the double-coating technology was further used to prepare the self-cleaning membranes with different TiO2 content. The effects of TiO2 nano-particles on membrane crystal form, morphology, porosity, pore size, pore size distribution, hydrophobicity, permeation, and photocatalytic efficiency were investigated, respectively. The flux of the prepared membranes is higher than the membrane (MS) provided by Membrane Solutions, LLC, in DCMD process. The contact angle between water and membrane could be increased 22° by introducing photocatalytic layer containing TiO2. During the photocatalytic test, 65.78-96.31% degrading rate of 15 mg/L Rhodamine B (RhB) was achieved. The relative flux of the membrane T-3 can be recovered to 0.96 in photocatalysis-membrane reactor for 8 h UV radiation. The fabricated membrane has great potential in high-salty dyeing wastewater treatment due to its high hydrophobicity and photocatalytic capability. [Figure not available: see fulltext.

  20. Fabrication of electrospun nanofibrous membranes for membrane distillation application

    KAUST Repository

    Francis, Lijo

    2013-02-01

    Nanofibrous membranes of Matrimid have been successfully fabricated using an electrospinning technique under optimized conditions. Nanofibrous membranes are found to be highly hydrophobic with a high water contact angle of 130°. Field emission scanning electron microscopy and pore size distribution analysis revealed the big pore size structure of electrospun membranes to be greater than 2 μm and the pore size distribution is found to be narrow. Flat sheet Matrimid membranes were fabricated via casting followed by phase inversion. The morphology, pore size distribution, and water contact angle were measured and compared with the electrospun membranes. Both membranes fabricated by electrospinning and phase inversion techniques were tested in a direct contact membrane distillation process. Electrospun membranes showed high water vapor flux of 56 kg/m2-h, which is very high compared to the casted membrane as well as most of the fabricated and commercially available highly hydrophobic membranes. ©2013 Desalination Publications.

  1. Functionalization of a Hydrophilic Commercial Membrane Using Inorganic-Organic Polymers Coatings for Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Lies Eykens

    2017-06-01

    Full Text Available Membrane distillation is a thermal separation technique using a microporous hydrophobic membrane. One of the concerns with respect to the industrialization of the technique is the development of novel membranes. In this paper, a commercially available hydrophilic polyethersulfone membrane with a suitable structure for membrane distillation was modified using available hydrophobic coatings using ORMOCER® technology to obtain a hydrophobic membrane that can be applied in membrane distillation. The surface modification was performed using a selection of different components, concentrations, and application methods. The resulting membranes can have two hydrophobic surfaces or a hydrophobic and hydrophilic surface depending on the application method. An extensive characterization procedure confirmed the suitability of the coating technique and the obtained membranes for membrane distillation. The surface contact angle of water could be increased from 27° up to 110°, and fluxes comparable to membranes commonly used for membrane distillation were achieved under similar process conditions. A 100 h test demonstrated the stability of the coating and the importance of using sufficiently stable base membranes.

  2. Polyoxadiazole hollow fibers for produced water treatment by direct contact membrane distillation

    KAUST Repository

    Xu, Jingli

    2018-01-08

    Treatment of produced water in the petroleum industry has been a challenge worldwide. In this study, we evaluated the use of direct contact membrane distillation (DCMD) for this purpose, removing oil and dissolved elements and supplying clean water from waste. We synthesized fluorinated polyoxadiazole, a highly hydrophobic polymer, to fabricate hollow fiber membranes, which were optimized and tested for simulated produced water and real produced water treatment. The process performance was investigated under different operating parameters, such as feed temperature, feed flow velocity and length of the membrane module for 4 days. The results indicate that by increasing feed temperature and feed flow rate the vapor flux increases. The flux decreased with increasing the length of the module due to the decrease of the driving force along the module. The fouling behavior, which corresponds to flux decline and cleaning efficiency of the membrane, was studied. The performance of the fabricated hollow fiber membranes was demonstrated for the treatment of produced water, complying with the industrial reuse and discharge limits.

  3. Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

    OpenAIRE

    Jiříček, T.; Komárek, M.; Lederer, T.

    2017-01-01

    Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest ...

  4. Performance modeling of direct contact membrane distillation (DCMD) seawater desalination process using a commercial composite membrane

    KAUST Repository

    Lee, Junggil

    2015-01-10

    This paper presents the development of a rigorous theoretical model to predict the transmembrane flux of a flat sheet hydrophobic composite membrane, comprising both an active layer of polytetrafluoroethylene and a scrim-backing support layer of polypropylene, in the direct contact membrane distillation (DCMD) process. An integrated model includes the mass, momentum, species and energy balances for both retentate and permeate flows, coupled with the mass transfer of water vapor through the composite membrane and the heat transfer across the membrane and through the boundary layers adjacent to the membrane surfaces. Experimental results and model predictions for permeate flux and performance ratio are compared and shown to be in good agreement. The permeate flux through the composite layer can be ignored in the consideration of mass transfer pathways at the composite membrane. The effect of the surface porosity and the thickness of active and support layers on the process performance of composite membrane has also been studied. Among these parameters, surface porosity is identified to be the main factor significantly influencing the permeate flux and performance ratio, while the relative influence of the surface porosity on the performance ratio is less than that on flux.

  5. Feedback control for distributed heat transfer mechanisms in direct-contact membrane distillation system

    KAUST Repository

    Eleiwi, Fadi; N'Doye, Ibrahima; Laleg-Kirati, Taous-Meriem

    2015-01-01

    In this paper, the problem of stabilization and production rate reference tracking for a Direct-Contact Membrane Distillation (DCMD) system is addressed. Sufficient conditions for the asymptotic and exponential stabilization for DCMD system are presented using the Gronwall-Bellman lemma and Linear Matrix Inequalities (LMIs) approaches, respectively. A nonlinear observer is then proposed to estimate the temperature distribution among the DCMD domain. This contributes to propose a reference production rate control design for the DCMD process via observer-based output control approach. Finally, numerical simulations are given to show the effectiveness of the proposed methods.

  6. Feedback control for distributed heat transfer mechanisms in direct-contact membrane distillation system

    KAUST Repository

    Eleiwi, Fadi

    2015-09-21

    In this paper, the problem of stabilization and production rate reference tracking for a Direct-Contact Membrane Distillation (DCMD) system is addressed. Sufficient conditions for the asymptotic and exponential stabilization for DCMD system are presented using the Gronwall-Bellman lemma and Linear Matrix Inequalities (LMIs) approaches, respectively. A nonlinear observer is then proposed to estimate the temperature distribution among the DCMD domain. This contributes to propose a reference production rate control design for the DCMD process via observer-based output control approach. Finally, numerical simulations are given to show the effectiveness of the proposed methods.

  7. Aroma Stripping under various Forms of Membrane Distillation Processes: Experiments and modeling

    DEFF Research Database (Denmark)

    Jonsson, Gunnar Eigil

    Concentration of fruit juices by membrane distillation is an interesting process as it can be done at low temperature giving a gentle concentration process with little deterioration of the juices. Since the juices contains many different aroma compounds with a wide range of chemical properties...... such as volatility, activity coefficient and vapor pressure, it is important to know how these aroma compounds will eventually pass through the membrane. Experiments have been made on an aroma model solution and on black currant juice in a lab scale membrane distillation set up which can be operated in various types...... of MD configurations: Vacuum Membrane Distillation , Sweeping Gas Membrane Distillation , Direct Contact Membrane Distillation and Osmotic Membrane Distillation. The influence of feed temperature and feed flow rate on the permeate flux and concentration factor for different types of aroma compounds have...

  8. Analysis of direct contact membrane distillation based on a lumped-parameter dynamic predictive model

    KAUST Repository

    Karam, Ayman M.; Alsaadi, Ahmad Salem; Ghaffour, NorEddine; Laleg-Kirati, Taous-Meriem

    2016-01-01

    Membrane distillation (MD) is an emerging technology that has a great potential for sustainable water desalination. In order to pave the way for successful commercialization of MD-based water desalination techniques, adequate and accurate dynamical models of the process are essential. This paper presents the predictive capabilities of a lumped-parameter dynamic model for direct contact membrane distillation (DCMD) and discusses the results under wide range of steady-state and dynamic conditions. Unlike previous studies, the proposed model captures the time response of the spacial temperature distribution along the flow direction. It also directly solves for the local temperatures at the membrane interfaces, which allows to accurately model and calculate local flux values along with other intrinsic variables of great influence on the process, like the temperature polarization coefficient (TPC). The proposed model is based on energy and mass conservation principles and analogy between thermal and electrical systems. Experimental data was collected to validated the steady-state and dynamic responses of the model. The obtained results shows great agreement with the experimental data. The paper discusses the results of several simulations under various conditions to optimize the DCMD process efficiency and analyze its response. This demonstrates some potential applications of the proposed model to carry out scale up and design studies. © 2016

  9. Analysis of direct contact membrane distillation based on a lumped-parameter dynamic predictive model

    KAUST Repository

    Karam, Ayman M.

    2016-10-03

    Membrane distillation (MD) is an emerging technology that has a great potential for sustainable water desalination. In order to pave the way for successful commercialization of MD-based water desalination techniques, adequate and accurate dynamical models of the process are essential. This paper presents the predictive capabilities of a lumped-parameter dynamic model for direct contact membrane distillation (DCMD) and discusses the results under wide range of steady-state and dynamic conditions. Unlike previous studies, the proposed model captures the time response of the spacial temperature distribution along the flow direction. It also directly solves for the local temperatures at the membrane interfaces, which allows to accurately model and calculate local flux values along with other intrinsic variables of great influence on the process, like the temperature polarization coefficient (TPC). The proposed model is based on energy and mass conservation principles and analogy between thermal and electrical systems. Experimental data was collected to validated the steady-state and dynamic responses of the model. The obtained results shows great agreement with the experimental data. The paper discusses the results of several simulations under various conditions to optimize the DCMD process efficiency and analyze its response. This demonstrates some potential applications of the proposed model to carry out scale up and design studies. © 2016

  10. Real time optimization of solar powered direct contact membrane distillation based on multivariable extremum seeking

    KAUST Repository

    Karam, Ayman M.; Laleg-Kirati, Taous-Meriem

    2015-01-01

    This paper presents a real time optimization scheme for a solar powered direct contact membrane distillation (DCMD) water desalination system. The sun and weather conditions vary and are inconsistent throughout the day. Therefore, the solar powered DCMD feed inlet temperature is never constant, which influences the distilled water flux. The problem of DCMD process optimization has not been studied enough. In this work, the response of the process under various feed inlet temperatures is investigated, which demonstrates the need for an optimal controller. To address this issue, we propose a multivariable Newton-based extremum seeking controller which optimizes the inlet feed and permeate mass flow rates as the feed inlet temperature varies. Results are presented and discussed for a realistic temperature profile.

  11. Real time optimization of solar powered direct contact membrane distillation based on multivariable extremum seeking

    KAUST Repository

    Karam, Ayman M.

    2015-09-21

    This paper presents a real time optimization scheme for a solar powered direct contact membrane distillation (DCMD) water desalination system. The sun and weather conditions vary and are inconsistent throughout the day. Therefore, the solar powered DCMD feed inlet temperature is never constant, which influences the distilled water flux. The problem of DCMD process optimization has not been studied enough. In this work, the response of the process under various feed inlet temperatures is investigated, which demonstrates the need for an optimal controller. To address this issue, we propose a multivariable Newton-based extremum seeking controller which optimizes the inlet feed and permeate mass flow rates as the feed inlet temperature varies. Results are presented and discussed for a realistic temperature profile.

  12. Direct Numerical Simulations of Concentration and Temperature Polarization in Direct Contact Membrane Distillation

    Science.gov (United States)

    Lou, Jincheng; Tilton, Nils

    2017-11-01

    Membrane distillation (MD) is a method of desalination with boundary layers that are challenging to simulate. MD is a thermal process in which warm feed and cool distilled water flow on opposite sides of a hydrophobic membrane. The temperature difference causes water to evaporate from the feed, travel through the membrane, and condense in the distillate. Two challenges to MD are temperature and concentration polarization. Temperature polarization represents a reduction in the transmembrane temperature difference due to heat transfer through the membrane. Concentration polarization describes the accumulation of solutes near the membrane. These phenomena reduce filtration and lead to membrane fouling. They are difficult to simulate due to the coupling between the velocity, temperature, and concentration fields on the membrane. Unsteady regimes are particularly challenging because noise at the outlets can pollute the near-membrane flow fields. We present the development of a finite-volume method for the simulation of fluid flow, heat, and mass transport in MD systems. Using the method, we perform a parametric study of the polarization boundary layers, and show that the concentration boundary layer shows self-similar behavior that satisfies power laws for the downstream growth. Funded by the U.S. Bureau of Reclamation.

  13. Performance and Fouling Study of Asymmetric PVDF Membrane Applied in the Concentration of Organic Fertilizer by Direct Contact Membrane Distillation (DCMD

    Directory of Open Access Journals (Sweden)

    Yanfei Liu

    2018-02-01

    Full Text Available This study proposes using membrane distillation (MD as an alternative to the conventional multi-stage flushing (MSF process to concentrate a semi-product of organic fertilizer. By applying a unique asymmetric polyvinylidene fluoride (PVDF membrane, which was specifically designed for MD applications using a nonsolvent thermally induced phase separation (NTIPS method, the direct contact membrane distillation (DCMD performance was investigated in terms of its sustainability in permeation flux, fouling resistance, and anti-wetting properties. It was found that the permeation flux increased with increasing flow rate, while the top-surface facing feed mode was the preferred orientation to achieve 25% higher flux than the bottom-surface facing feed mode. Compared to the commercial polytetrafluoroethylene (PTFE membrane, the asymmetric PVDF membrane exhibited excellent anti-fouling and sustainable flux, with less than 8% flux decline in a 15 h continuous operation, i.e., flux decreased slightly and was maintained as high as 74 kg·m−2·h−1 at 70 °C. Meanwhile, the lost flux was easily recovered by clean water rinsing. Overall 2.6 times concentration factor was achieved in 15 h MD operation, with 63.4% water being removed from the fertilizer sample. Further concentration could be achieved to reach the desired industrial standard of 5x concentration factor.

  14. Fouling development in direct contact membrane distillation: Non-invasive monitoring and destructive analysis

    KAUST Repository

    Fortunato, Luca

    2017-12-26

    Fouling development in direct contact membrane distillation (DCMD) for seawater desalination was evaluated combining in-situ monitoring performed using optical coherence tomography (OCT) together with destructive techniques. The non-invasive monitoring with OCT provided a better understanding of the fouling mechanism by giving an appropriate sampling timing for the membrane autopsy. The on-line monitoring system allowed linking the flux trend with the structure of fouling deposited on the membrane surface. The water vapor flux trend was divided in three phases based on the deposition and formation of different foulants over time. The initial flux decline was due to the deposition of a 50–70 nm porous fouling layer consisting of a mixture of organic compounds and salts. Liquid chromatography with organic carbon detection (LC-OCD) analysis revealed the abundance of biopolymer in the fouling layer formed at the initial phase. In the second phase, formation of carbonate crystals on the membrane surface was observed but did not affect the flux significantly. In the last phase, the water vapor flux dropped to almost zero due to the deposition of a dense thick layer of sulfate crystals on the membrane surface.

  15. Performance of different hollow fiber membranes for seawater desalination using membrane distillation

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Amy, Gary L.

    2014-01-01

    Membrane distillation requires a highly porous hydrophobic membrane with low surface energy. In this paper, we compare the direct contact membrane distillation (DCMD) performances of four different types of in-house fabricated hollow fiber membranes and two different commercially available hollow fiber membranes. Hollow fiber membranes are fabricated using wet-jet phase inversion technique and the polymeric matrices used for the fabrication are polyvinylidine fluoride (PVDF) and polyvinyl chloride (PVC). Commercial hollow fiber membrane materials are made of polytetrafluoroethylene (PTFE) and polypropylene (PP). PVDF hollow fibers showed a superior performance among all the hollow fibers tested in the DCMD process and gave a water vapor flux of 31 kg m-2h-1 at a feed and coolant inlet temperatures of 80 and 20°C, respectively. Under the same conditions, the water vapor flux observed for PP, PTFE, and PVC hollow fiber membranes are 13, 11, and 6 kg m-2h-1, respectively, with 99.99% salt rejection observed for all membranes used.

  16. Performance of different hollow fiber membranes for seawater desalination using membrane distillation

    KAUST Repository

    Francis, Lijo

    2014-08-11

    Membrane distillation requires a highly porous hydrophobic membrane with low surface energy. In this paper, we compare the direct contact membrane distillation (DCMD) performances of four different types of in-house fabricated hollow fiber membranes and two different commercially available hollow fiber membranes. Hollow fiber membranes are fabricated using wet-jet phase inversion technique and the polymeric matrices used for the fabrication are polyvinylidine fluoride (PVDF) and polyvinyl chloride (PVC). Commercial hollow fiber membrane materials are made of polytetrafluoroethylene (PTFE) and polypropylene (PP). PVDF hollow fibers showed a superior performance among all the hollow fibers tested in the DCMD process and gave a water vapor flux of 31 kg m-2h-1 at a feed and coolant inlet temperatures of 80 and 20°C, respectively. Under the same conditions, the water vapor flux observed for PP, PTFE, and PVC hollow fiber membranes are 13, 11, and 6 kg m-2h-1, respectively, with 99.99% salt rejection observed for all membranes used.

  17. PVDF hollow fiber and nanofiber membranes for fresh water reclamation using membrane distillation

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Nunes, Suzana Pereira; Amy, Gary L.

    2013-01-01

    Polyvinylidene fluoride hollow fiber and nanofibrous membranes are engineered and successfully fabricated using dry-jet wet spinning and electrospinning techniques, respectively. Fabricated membranes are characterized for their morphology, average pore size, pore size distribution, nanofiber diameter distribution, thickness, and water contact angle. Direct contact membrane distillation (DCMD) performances of the fabricated membranes have been investigated using a locally designed and fabricated, fully automated MD bench scale unit and DCMD module. Electrospun nanofibrous membranes showed a water flux as high as 36 L m-2 h-1 whereas hollow fiber membranes showed a water flux of 31.6 L m-2 h-1, at a feed inlet temperature of 80 °C and at a permeate inlet temperature of 20 °C.

  18. PVDF hollow fiber and nanofiber membranes for fresh water reclamation using membrane distillation

    KAUST Repository

    Francis, Lijo

    2013-11-26

    Polyvinylidene fluoride hollow fiber and nanofibrous membranes are engineered and successfully fabricated using dry-jet wet spinning and electrospinning techniques, respectively. Fabricated membranes are characterized for their morphology, average pore size, pore size distribution, nanofiber diameter distribution, thickness, and water contact angle. Direct contact membrane distillation (DCMD) performances of the fabricated membranes have been investigated using a locally designed and fabricated, fully automated MD bench scale unit and DCMD module. Electrospun nanofibrous membranes showed a water flux as high as 36 L m-2 h-1 whereas hollow fiber membranes showed a water flux of 31.6 L m-2 h-1, at a feed inlet temperature of 80 °C and at a permeate inlet temperature of 20 °C.

  19. Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

    Directory of Open Access Journals (Sweden)

    T. Jiříček

    2017-01-01

    Full Text Available Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest flux was achieved with the thinnest membranes and the best energy efficiency was achieved with the thickest membranes. All membranes had salt retention above 99%. Nanotechnology offers the potential to find modern solutions for desalination of waste waters, by introducing new materials with revolutionary properties, but new membranes must be developed according to the target application.

  20. Reduced-Order Dynamic Modeling, Fouling Detection, and Optimal Control of Solar-Powered Direct Contact Membrane Distillation

    KAUST Repository

    Karam, Ayman M.

    2016-12-01

    Membrane Distillation (MD) is an emerging sustainable desalination technique. While MD has many advantages and can be powered by solar thermal energy, its main drawback is the low water production rate. However, the MD process has not been fully optimized in terms of its manipulated and controlled variables. This is largely due to the lack of adequate dynamic models to study and simulate the process. In addition, MD is prone to membrane fouling, which is a fault that degrades the performance of the MD process. This work has three contributions to address these challenges. First, we derive a mathematical model of Direct Contact Membrane Distillation (DCMD), which is the building block for the next parts. Then, the proposed model is extended to account for membrane fouling and an observer-based fouling detection method is developed. Finally, various control strategies are implemented to optimize the performance of the DCMD solar-powered process. In part one, a reduced-order dynamic model of DCMD is developed based on lumped capacitance method and electrical analogy to thermal systems. The result is an electrical equivalent thermal network to the DCMD process, which is modeled by a system of nonlinear differential algebraic equations (DAEs). This model predicts the water-vapor flux and the temperature distribution along the module length. Experimental data is collected to validate the steady-state and dynamic responses of the proposed model, with great agreement demonstrated in both. The second part proposes an extension of the model to account for membrane fouling. An adaptive observer for DAE systems is developed and convergence proof is presented. A method for membrane fouling detection is then proposed based on adaptive observers. Simulation results demonstrate the performance of the membrane fouling detection method. Finally, an optimization problem is formulated to maximize the process efficiency of a solar-powered DCMD. The adapted method is known as Extremum

  1. Pore channel surface modification for enhancing anti-fouling membrane distillation

    Science.gov (United States)

    Qiu, Haoran; Peng, Yuelian; Ge, Lei; Villacorta Hernandez, Byron; Zhu, Zhonghua

    2018-06-01

    Membrane surface modification by forming a functional layer is an effective way to improve the anti-fouling properties of membranes; however, the additional layer and the potential blockage of bulk pores may increase the mass transfer resistance and reduce the permeability. In this study, we applied a novel method of preparing anti-fouling membranes for membrane distillation by dispersing graphene oxide (GO) on the channel surface of polyvinylidene fluoride membranes. The surface morphology and properties were characterized by scanning electron microscopy, atomic force microscope, and Fourier transform infrared spectrometry. Compared to the membrane surface modification by nanoparticles (e.g. SiO2), GO was mainly located on the pore surface of the membrane bulk, rather than being formed as an individual layer onto the membrane surface. The performance was evaluated via a direct-contact membrane distillation process with anionic and cationic surfactants as the foulants, separately. Compared to the pristine PVDF membrane, the anti-fouling behavior and distillate flux of the GO-modified membranes were improved, especially when using the anionic surfactant as the foulant. The enhanced anti-fouling performance can be attributed to the oxygen containing functional groups in GO and the healing of the membrane pore defects. This method may provide an effective route to manipulate membrane pore surface properties for anti-fouling separation without increasing mass transfer resistance.

  2. Membrane distillation for milk concentration

    NARCIS (Netherlands)

    Moejes, S.N.; Romero Guzman, Maria; Hanemaaijer, J.H.; Barrera, K.H.; Feenstra, L.; Boxtel, van A.J.B.

    2015-01-01

    Membrane distillation is an emerging technology to concentrate liquid products while producing high quality water as permeate. Application for desalination has been studied extensively the past years, but membrane distillation has also potential to produce concentrated food products like

  3. Dynamic modeling and experimental validation for direct contact membrane distillation (DCMD) process

    KAUST Repository

    Eleiwi, Fadi

    2016-02-01

    This work proposes a mathematical dynamic model for the direct contact membrane distillation (DCMD) process. The model is based on a 2D Advection–Diffusion Equation (ADE), which describes the heat and mass transfer mechanisms that take place inside the DCMD module. The model studies the behavior of the process in the time varying and the steady state phases, contributing to understanding the process performance, especially when it is driven by intermittent energy supply, such as the solar energy. The model is experimentally validated in the steady state phase, where the permeate flux is measured for different feed inlet temperatures and the maximum absolute error recorded is 2.78 °C. Moreover, experimental validation includes the time variation phase, where the feed inlet temperature ranges from 30 °C to 75 °C with 0.1 °C increment every 2min. The validation marks relative error to be less than 5%, which leads to a strong correlation between the model predictions and the experiments.

  4. Dynamic modeling and experimental validation for direct contact membrane distillation (DCMD) process

    KAUST Repository

    Eleiwi, Fadi; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Francis, Lijo; Laleg-Kirati, Taous-Meriem

    2016-01-01

    This work proposes a mathematical dynamic model for the direct contact membrane distillation (DCMD) process. The model is based on a 2D Advection–Diffusion Equation (ADE), which describes the heat and mass transfer mechanisms that take place inside the DCMD module. The model studies the behavior of the process in the time varying and the steady state phases, contributing to understanding the process performance, especially when it is driven by intermittent energy supply, such as the solar energy. The model is experimentally validated in the steady state phase, where the permeate flux is measured for different feed inlet temperatures and the maximum absolute error recorded is 2.78 °C. Moreover, experimental validation includes the time variation phase, where the feed inlet temperature ranges from 30 °C to 75 °C with 0.1 °C increment every 2min. The validation marks relative error to be less than 5%, which leads to a strong correlation between the model predictions and the experiments.

  5. Submerged membrane distillation for seawater desalination

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Amy, Gary L.

    2014-01-01

    A submerged membrane distillation (SMD) process for fresh water production from Red Sea water using commercially available hollow fiber membranes has been successfully employed and compared with the conventional direct contact membrane distillation (DCMD) process. The hollow fiber membranes have been characterized for its morphology using field effect scanning electron microscope. In SMD process, a bunch of hollow fiber membranes are glued together at both ends to get a simplified open membrane module assembly submerged into the coolant tank equipped with a mechanical stirrer. Hot feed stream is allowed to pass through the lumen side of the membrane using a feed pump. Continuous stirring at the coolant side will reduce the temperature and concentration polarization. During the conventional DCMD process, using feed-coolant streams with co-current and counter-current flows has been tested and the results are compared in this study. In SMD process, a water vapor flux of 10.2 kg m-2 h-1 is achieved when using a feed inlet temperature of 80°C and coolant temperature of 20°C. Under the same conditions, during conventional DCMD process, a water vapor flux of 11.6 and 10.1 kg m-2 h-1 were observed during counter-current and co-current flow streams, respectively. Results show that the water production in the SMD process is comparable with the conventional DCMD process, while the feed-coolant flow streams are in the co-current direction. During conventional DCMD operation, a 15% increase in the water production is observed when feed-coolant streams are in the counter-current direction compared to the co-current direction. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  6. Submerged membrane distillation for seawater desalination

    KAUST Repository

    Francis, Lijo

    2014-08-11

    A submerged membrane distillation (SMD) process for fresh water production from Red Sea water using commercially available hollow fiber membranes has been successfully employed and compared with the conventional direct contact membrane distillation (DCMD) process. The hollow fiber membranes have been characterized for its morphology using field effect scanning electron microscope. In SMD process, a bunch of hollow fiber membranes are glued together at both ends to get a simplified open membrane module assembly submerged into the coolant tank equipped with a mechanical stirrer. Hot feed stream is allowed to pass through the lumen side of the membrane using a feed pump. Continuous stirring at the coolant side will reduce the temperature and concentration polarization. During the conventional DCMD process, using feed-coolant streams with co-current and counter-current flows has been tested and the results are compared in this study. In SMD process, a water vapor flux of 10.2 kg m-2 h-1 is achieved when using a feed inlet temperature of 80°C and coolant temperature of 20°C. Under the same conditions, during conventional DCMD process, a water vapor flux of 11.6 and 10.1 kg m-2 h-1 were observed during counter-current and co-current flow streams, respectively. Results show that the water production in the SMD process is comparable with the conventional DCMD process, while the feed-coolant flow streams are in the co-current direction. During conventional DCMD operation, a 15% increase in the water production is observed when feed-coolant streams are in the counter-current direction compared to the co-current direction. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  7. Effect of feed flow pattern on the distribution of permeate fluxes in desalination by direct contact membrane distillation

    KAUST Repository

    Soukane, Sofiane

    2017-05-31

    The current study aims to highlight the effect of flow pattern on the variations of permeate fluxes over the membrane surface during desalination in a direct contact membrane distillation (DCMD) flat module. To do so, a three dimensional (3D) Computational Fluid Dynamics (CFD) model with embedded pore scale calculations is implemented to predict flow, heat and mass transfer in the DCMD module. Model validation is carried out in terms of average permeate fluxes with experimental data of seawater desalination using two commercially available PTFE membranes. Average permeate fluxes agree within 6% and less with experimental values without fitting parameters. Simulation results show that the distribution of permeate fluxes and seawater salinity over the membrane surface are strongly dependent on momentum and heat transport and that temperature and concentration polarization follow closely the flow distribution. The analysis reveals a drastic effect of recirculation loops and dead zones on module performance and recommendations to improve MD flat module design are drawn consequently.

  8. Plasma treatment of polyethersulfone membrane for benzene removal from water by air gap membrane distillation.

    Science.gov (United States)

    Pedram, Sara; Mortaheb, Hamid Reza; Arefi-Khonsari, Farzaneh

    2018-01-01

    In order to obtain a durable cost-effective membrane for membrane distillation (MD) process, flat sheet polyethersulfone (PES) membranes were modified by an atmospheric pressure nonequilibrium plasma generated using a dielectric barrier discharge in a mixture of argon and hexamethyldisiloxane as the organosilicon precursor. The surface properties of the plasma-modified membranes were characterized by water contact angle (CA), liquid entry pressure, X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy. The water CA of the membrane was increased from 64° to 104° by depositing a Si(CH 3 )-rich thin layer. While the pristine PES membrane was not applicable in the MD process, the modified PES membrane could be applied for the first time in an air gap membrane distillation setup for the removal of benzene as a volatile organic compound from water. The experimental design using central composite design and response surface methodology was applied to study the effects of feed temperature, concentration, and flow rate as well as their binary interactions on the overall permeate flux and separation factor. The separation factor and permeation flux of the modified PES membrane at optimum conditions were comparable with those of commercial polytetrafluoroethylene membrane.

  9. Engineering Hydrophobic Organosilica Nanoparticle-Doped Nanofibers for Enhanced and Fouling Resistant Membrane Distillation

    KAUST Repository

    Hammami, Mohamed Amen; Croissant, Jonas G.; Francis, Lijo; Alsaiari, Shahad K.; Anjum, Dalaver H.; Ghaffour, NorEddine; Khashab, Niveen M.

    2016-01-01

    Engineering and scaling-up new materials for better water desalination are imperative to find alternative fresh water sources to meet future demands. Herein, the fabrication of hydrophobic poly(ether imide) composite nanofiber membranes doped with novel ethylene-pentafluorophenylene-based periodic mesoporous organosilica nanoparticles is reported for enhanced and fouling resistant membrane distillation. Novel organosilica nanoparticles were homogeneously incorporated into electrospun nanofiber membranes depicting a proportional increase of hydrophobicity to the particle contents. Direct contact membrane distillation experiments on the organosilica-doped membrane with only 5% doping showed an increase of flux of 140% compared to commercial membranes. The high porosity of organosilica nanoparticles was further utilized to load the eugenol antimicrobial agent which produced a dramatic enhancement of the antibiofouling properties of the membrane of 70% after 24 h.

  10. Engineering Hydrophobic Organosilica Nanoparticle-Doped Nanofibers for Enhanced and Fouling Resistant Membrane Distillation

    KAUST Repository

    Hammami, Mohamed Amen

    2016-12-15

    Engineering and scaling-up new materials for better water desalination are imperative to find alternative fresh water sources to meet future demands. Herein, the fabrication of hydrophobic poly(ether imide) composite nanofiber membranes doped with novel ethylene-pentafluorophenylene-based periodic mesoporous organosilica nanoparticles is reported for enhanced and fouling resistant membrane distillation. Novel organosilica nanoparticles were homogeneously incorporated into electrospun nanofiber membranes depicting a proportional increase of hydrophobicity to the particle contents. Direct contact membrane distillation experiments on the organosilica-doped membrane with only 5% doping showed an increase of flux of 140% compared to commercial membranes. The high porosity of organosilica nanoparticles was further utilized to load the eugenol antimicrobial agent which produced a dramatic enhancement of the antibiofouling properties of the membrane of 70% after 24 h.

  11. Membrane distillation against a pressure difference

    NARCIS (Netherlands)

    Keulen, L.; Ham, L.V. van der; Kuipers, N.J.M.; Hanemaaijer, J.H.; Vlugt, T.J.H.; Kjelstrup, S.

    2017-01-01

    Membrane distillation is an attractive technology for production of fresh water from seawater. The MemPower® concept, studied in this work, uses available heat (86 °C) to produce pressurized water (2.2 bar and 46 °C) by membrane distillation, which again can be used to power a turbine for

  12. Membrane distillation against a pressure difference

    OpenAIRE

    Keulen, L.; van der Ham, L.V.; Kuipers, N.J.M.; Hanemaaijer, J.H.; Vlugt, T.J.H.; Kjelstrup, S.

    2017-01-01

    Membrane distillation is an attractive technology for production of fresh water from seawater. The MemPower®MemPower® concept, studied in this work, uses available heat (86 °C) to produce pressurized water (2.2 bar and 46 °C) by membrane distillation, which again can be used to power a turbine for co-production of electricity. We develop a non-equilibrium thermodynamic model to accurately describe the transfer at the liquid-membrane interfaces, as well as through the hydrophobic membrane. The...

  13. Vacuum membrane distillation of liquid desiccants Utilizing Hollow Fiber Membranes

    KAUST Repository

    Lefers, Ryan

    2018-01-31

    This paper documents the testing of a vacuum membrane distillation system intended for use with liquid desiccants. Liquid desiccants offer the possibility for low-energy, ambient temperature dehumidification. Effective desalination and purification of diluted desiccants outputs two important products: a concentrated desiccant for reuse in dehumidification and fresh water. In this study, vacuum membrane distillation was used in the laboratory to purify diluted liquid desiccants. Calcium chloride and magnesium chloride were the desiccants selected for testing. Desiccant solutions were pumped through the lumens of poly(vinylidene fluoride) (PVDF) hollow fiber membranes at varying feed inlet temperatures, solution velocity rates and vacuum set points during membrane distillation. An average flux of 8 kg m-2 h-1 was obtained using 30 wt% magnesium chloride solution at a temperature of 50 °C while applying vacuum to achieve 25 mbar absolute pressure on the air side of the membrane. The results are promising for the development of a full-scale vacuum membrane distillation process for desiccant solution regeneration and fresh water recovery. In addition, the recovered condensate was of sufficient quality for use in agricultural irrigation or drinking water.

  14. Vacuum membrane distillation of liquid desiccants Utilizing Hollow Fiber Membranes

    KAUST Repository

    Lefers, Ryan; Srivatsa Bettahalli, N.M.; Fedoroff, Nina V.; Nunes, Suzana Pereira; Leiknes, TorOve

    2018-01-01

    This paper documents the testing of a vacuum membrane distillation system intended for use with liquid desiccants. Liquid desiccants offer the possibility for low-energy, ambient temperature dehumidification. Effective desalination and purification of diluted desiccants outputs two important products: a concentrated desiccant for reuse in dehumidification and fresh water. In this study, vacuum membrane distillation was used in the laboratory to purify diluted liquid desiccants. Calcium chloride and magnesium chloride were the desiccants selected for testing. Desiccant solutions were pumped through the lumens of poly(vinylidene fluoride) (PVDF) hollow fiber membranes at varying feed inlet temperatures, solution velocity rates and vacuum set points during membrane distillation. An average flux of 8 kg m-2 h-1 was obtained using 30 wt% magnesium chloride solution at a temperature of 50 °C while applying vacuum to achieve 25 mbar absolute pressure on the air side of the membrane. The results are promising for the development of a full-scale vacuum membrane distillation process for desiccant solution regeneration and fresh water recovery. In addition, the recovered condensate was of sufficient quality for use in agricultural irrigation or drinking water.

  15. Membrane distillation against a pressure difference

    NARCIS (Netherlands)

    Keulen, L.; van der Ham, LV; Kuipers, N.J.M.; Hanemaaijer, J.H.; Vlugt, T.J.H.; Kjelstrup, S

    2017-01-01

    Membrane distillation is an attractive technology for production of fresh water from seawater. The MemPower®MemPower® concept, studied in this work, uses available heat (86 °C) to produce pressurized water (2.2 bar and 46 °C) by membrane distillation, which again can be used to power a turbine for

  16. Removal of arsenic from contaminated groundwater by solar-driven membrane distillation

    International Nuclear Information System (INIS)

    Manna, Ajay K.; Sen, Mou; Martin, Andrew R.; Pal, Parimal

    2010-01-01

    Experimental investigations were carried out on removal of arsenic from contaminated groundwater by employing a new flat-sheet cross flow membrane module fitted with a hydrophobic polyvinylidenefluoride (PVDF) microfiltration membrane. The new design of the solar-driven membrane module in direct contact membrane distillation (DCMD) configuration successfully produced almost 100 per cent arsenic-free water from contaminated groundwater in a largely fouling-free operation while permitting high fluxes under reduced temperature polarization. For a feed flow rate of 0.120 m 3 /h, the 0.13 μm PVDF membrane yielded a high flux of 74 kg/(m 2 h) at a feed water temperature of 40 deg. C and, 95 kg/m 2 h at a feed water temperature of 60 deg. C. The encouraging results show that the design could be effectively exploited in the vast arsenic-affected rural areas of South-East Asian countries blessed with abundant sunlight particularly during the critical dry season. - Solar-driven membrane distillation has the potential of removing arsenic from contaminated groundwater.

  17. A novel multi-stage direct contact membrane distillation module: Design, experimental and theoretical approaches

    KAUST Repository

    Lee, Jung Gil

    2016-10-24

    An economic desalination system with a small scale and footprint for remote areas, which have a limited and inadequate water supply, insufficient water treatment and low infrastructure, is strongly demanded in the desalination markets. Here, a direct contact membrane distillation (DCMD) process has the simplest configuration and potentially the highest permeate flux among all of the possible MD processes. This process can also be easily instituted in a multi-stage manner for enhanced compactness, productivity, versatility and cost-effectiveness. In this study, an innovative, multi-stage, DCMD module under countercurrent-flow configuration is first designed and then investigate both theoretically and experimentally to identify its feasibility and operability for desalination application. Model predictions and measured data for mean permeate flux are compared and shown to be in good agreement. The effect of the number of module stages on the mean permeate flux, performance ratio and daily water production of the MDCMD system has been theoretically identified at inlet feed and permeate flow rates of 1.5 l/min and inlet feed and permeate temperatures of 70 °C and 25 °C, respectively. The daily water production of a three-stage DCMD module with a membrane area of 0.01 m2 at each stage is found to be 21.5 kg.

  18. Advances in Membrane Distillation for Water Desalination and Purification Applications

    Directory of Open Access Journals (Sweden)

    Juan Gomez

    2013-01-01

    Full Text Available Membrane distillation is a process that utilizes differences in vapor pressure to permeate water through a macro-porous membrane and reject other non-volatile constituents present in the influent water. This review considers the fundamental heat and mass transfer processes in membrane distillation, recent advances in membrane technology, module configurations, and the applications and economics of membrane distillation, and identifies areas that may lead to technological improvements in membrane distillation as well as the application characteristics required for commercial deployment.

  19. Desalination and water recycling by air gap membrane distillation

    NARCIS (Netherlands)

    Meindersma, G.W.; Guijt, C.M.; Haan, de A.B.

    2006-01-01

    Membrane distillation (MD) is an emerging technology for desalination. Membrane distillation differs from other membrane technologies in that the driving force for desalination is the difference in vapour pressure of water across the membrane, rather than total pressure. The membranes for MD are

  20. Desalination and Water Recycling by Air Gap Membrane Distillation

    NARCIS (Netherlands)

    Meindersma, G.W.; Guijt, C.M.; de Haan, A.B.

    2006-01-01

    Membrane distillation (MD) is an emerging technology for desalination. Membrane distillation differs from other membrane technologies in that the driving force for desalination is the difference in vapour pressure of water across the membrane, rather than total pressure. The membranes for MD are

  1. Performance investigation of a solar-assisted direct contact membrane distillation system

    KAUST Repository

    Kim, Youngdeuk

    2013-01-01

    This paper presents a solar-assisted direct contact membrane distillation (DCMD) system with novel energy recovery concepts for a continuous 24-h-a-day operation. A temperature modulating scheme is introduced to the solar-thermal system that supplies feed seawater to the DCMD modules. This scheme attenuates extreme temperature fluctuations of the feed water by storing the collected energy during solar-peak hours and reutilizing it throughout the day. Thus, the energy savings is realized yet the feed seawater temperature is maintained within the desired range. Additionally, the system employs heat recovery from the permeate and brine streams to the feed seawater. The simulations for such a system with a shell-and-tube type DCMD modules are carried out to examine the spatial property variations and the sensitivity of system performance (i.e., transmembrane pressure, permeate flux and performance ratio) to the operating conditions (inlet temperature and flow rate) and the fiber dimensions (fiber length and packing density). It is found that there are trade-offs between mean permeate flux and performance ratio with respect to permeate inlet temperature and flow rate and between total distillate production and performance ratio with respect to packing density. For the solar-assisted DCMD system having evacuated-tube collectors of 3360m2 with 160m3 seawater storage tanks and 50 DCMD modules, the annual solar fraction and the collector efficiency are found to be 77% and 53%, respectively, whilst the overall permeate production capacity is 31m3/day. The overall specific thermal energy consumption of the DCMD system with heat recovery is found to be 436kWh/m3 and it is about 43% lower as compared to the system without heat recovery. It is observed that the specific thermal energy consumption decreases significantly by 55% with increased collector area from 1983m2 to 3360m2 whereas the specific electrical energy consumption increases slightly by 16%. © 2012 Elsevier B.V.

  2. A Framework for Better Understanding and Enhancing Direct Contact Membrane Distillation (DCMD) in Terms of Module Design, Cost Analysis and Energy Required

    KAUST Repository

    AbuHannoud, Ali

    2011-07-01

    Water is becoming scarcer and several authors have highlighted the upcoming problem of higher water salinity and the difficulty of treating and discharging water. Moreover, current discoveries of problems with chemicals that have been used for pretreating or post-treating water alerted scientists to research better solutions to treat water. Membrane distillation (MD) is a promising technology that might replace current processes as it has lower pretreatment requirements combined with a tremendous ability to treat a wide range of feed sources while producing very high product quality. If it enters the market, it will have a big influence on all products, from food industry to spaceflight. However, there are several problems which make MD a hot topic for research. One of them is the question about the real cost of MD in terms of heating feed and cooling distillate over time with respect to product quantity and quality. In this work, extensive heating and cooling analyses are covered to answer this question in order to enhance the MD process. Results show energy cost to produce water and the main source of energy loss for direct contact membrane distillation (DCMD), and several suggestions are made in order to better understand and hence enhance the process.

  3. Utilization of solar energy for direct contact membrane distillation process: An experimental study for desalination of real seawater

    International Nuclear Information System (INIS)

    Palanisami, Nallasamy; He, Ke; Moon, Il Shik

    2014-01-01

    Membrane distillation (MD), a non-isothermal membrane separation process, is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions by passing vapor through a hydrophobic microporous membrane when a temperature difference is established across it. We used three commercially available hydrophobic microporous membranes (C02, C07 and C12; based on the pore size 0.2, 0.7 and 1.2 µm respectively) for desalination via direct contact MD (DCMD). The effects of operating parameters on permeation flux were studied. In addition, the desalination of seawater by solar assisted DCMD process was experimentally investigated. First, using solar power only short-term (one day), successful desalination of real seawater was achieved without temperature control under the following conditions: feed inlet temperature 65.0 .deg. C, permeate inlet temperature 25.0 .deg. C, and a flow rate of 2.5 L/min. The developed system also worked well in the long-term (150 days) for seawater desalination using both solar and electric power. Long-term test flux was reduced from 28.48 to only 26.50 L/m 2 hr, indicating system feasibility

  4. Utilization of solar energy for direct contact membrane distillation process: An experimental study for desalination of real seawater

    Energy Technology Data Exchange (ETDEWEB)

    Palanisami, Nallasamy; He, Ke; Moon, Il Shik [Sunchon National University, Suncheon (Korea, Republic of)

    2014-01-15

    Membrane distillation (MD), a non-isothermal membrane separation process, is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions by passing vapor through a hydrophobic microporous membrane when a temperature difference is established across it. We used three commercially available hydrophobic microporous membranes (C02, C07 and C12; based on the pore size 0.2, 0.7 and 1.2 µm respectively) for desalination via direct contact MD (DCMD). The effects of operating parameters on permeation flux were studied. In addition, the desalination of seawater by solar assisted DCMD process was experimentally investigated. First, using solar power only short-term (one day), successful desalination of real seawater was achieved without temperature control under the following conditions: feed inlet temperature 65.0 .deg. C, permeate inlet temperature 25.0 .deg. C, and a flow rate of 2.5 L/min. The developed system also worked well in the long-term (150 days) for seawater desalination using both solar and electric power. Long-term test flux was reduced from 28.48 to only 26.50 L/m{sup 2}hr, indicating system feasibility.

  5. Improving Nanofiber Membrane Characteristics and Membrane Distillation Performance of Heat-Pressed Membranes via Annealing Post-Treatment

    Directory of Open Access Journals (Sweden)

    Minwei Yao

    2017-01-01

    Full Text Available Electrospun membranes are gaining interest for use in membrane distillation (MD due to their high porosity and interconnected pore structure; however, they are still susceptible to wetting during MD operation because of their relatively low liquid entry pressure (LEP. In this study, post-treatment had been applied to improve the LEP, as well as its permeation and salt rejection efficiency. The post-treatment included two continuous procedures: heat-pressing and annealing. In this study, annealing was applied on the membranes that had been heat-pressed. It was found that annealing improved the MD performance as the average flux reached 35 L/m2·h or LMH (>10% improvement of the ones without annealing while still maintaining 99.99% salt rejection. Further tests on LEP, contact angle, and pore size distribution explain the improvement due to annealing well. Fourier transform infrared spectroscopy and X-ray diffraction analyses of the membranes showed that there was an increase in the crystallinity of the polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP membrane; also, peaks indicating the α phase of polyvinylidene fluoride (PVDF became noticeable after annealing, indicating some β and amorphous states of polymer were converted into the α phase. The changes were favorable for membrane distillation as the non-polar α phase of PVDF reduces the dipolar attraction force between the membrane and water molecules, and the increase in crystallinity would result in higher thermal stability. The present results indicate the positive effect of the heat-press followed by an annealing post-treatment on the membrane characteristics and MD performance.

  6. A novel multi-stage direct contact membrane distillation module: Design, experimental and theoretical approaches.

    Science.gov (United States)

    Lee, Jung-Gil; Kim, Woo-Seung; Choi, June-Seok; Ghaffour, Noreddine; Kim, Young-Deuk

    2016-12-15

    An economic desalination system with a small scale and footprint for remote areas, which have a limited and inadequate water supply, insufficient water treatment and low infrastructure, is strongly demanded in the desalination markets. Here, a direct contact membrane distillation (DCMD) process has the simplest configuration and potentially the highest permeate flux among all of the possible MD processes. This process can also be easily instituted in a multi-stage manner for enhanced compactness, productivity, versatility and cost-effectiveness. In this study, an innovative, multi-stage, DCMD module under countercurrent-flow configuration is first designed and then investigate both theoretically and experimentally to identify its feasibility and operability for desalination application. Model predictions and measured data for mean permeate flux are compared and shown to be in good agreement. The effect of the number of module stages on the mean permeate flux, performance ratio and daily water production of the MDCMD system has been theoretically identified at inlet feed and permeate flow rates of 1.5 l/min and inlet feed and permeate temperatures of 70 °C and 25 °C, respectively. The daily water production of a three-stage DCMD module with a membrane area of 0.01 m 2  at each stage is found to be 21.5 kg. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Observer-Based Perturbation Extremum Seeking Control with Input Constraints for Direct-Contact Membrane Distillation Process

    KAUST Repository

    Eleiwi, Fadi

    2017-05-08

    An Observer-based Perturbation Extremum Seeking Control (PESC) is proposed for a Direct-Contact Membrane Distillation (DCMD) process. The process is described with a dynamic model that is based on a 2D Advection-Diffusion Equation (ADE) model which has pump flow rates as process inputs. The objective of the controller is to optimize the trade-off between the permeate mass flux and the energy consumption by the pumps inside the process. Cases of single and multiple control inputs are considered through the use of only the feed pump flow rate or both the feed and the permeate pump flow rates. A nonlinear Lyapunov-based observer is designed to provide an estimation for the temperature distribution all over the designated domain of the DCMD process. Moreover, control inputs are constrained with an anti-windup technique to be within feasible and physical ranges. Performance of the proposed structure is analyzed, and simulations based on real DCMD process parameters for each control input are provided.

  8. Observer-based perturbation extremum seeking control with input constraints for direct-contact membrane distillation process

    Science.gov (United States)

    Eleiwi, Fadi; Laleg-Kirati, Taous Meriem

    2018-06-01

    An observer-based perturbation extremum seeking control is proposed for a direct-contact membrane distillation (DCMD) process. The process is described with a dynamic model that is based on a 2D advection-diffusion equation model which has pump flow rates as process inputs. The objective of the controller is to optimise the trade-off between the permeate mass flux and the energy consumption by the pumps inside the process. Cases of single and multiple control inputs are considered through the use of only the feed pump flow rate or both the feed and the permeate pump flow rates. A nonlinear Lyapunov-based observer is designed to provide an estimation for the temperature distribution all over the designated domain of the DCMD process. Moreover, control inputs are constrained with an anti-windup technique to be within feasible and physical ranges. Performance of the proposed structure is analysed, and simulations based on real DCMD process parameters for each control input are provided.

  9. Experimental and theoretical analyses of temperature polarization effect in vacuum membrane distillation

    KAUST Repository

    Alsaadi, Ahmad Salem; Francis, Lijo; Amy, Gary L.; Ghaffour, NorEddine

    2014-01-01

    This paper discusses the effect of temperature polarization in Vacuum Membrane Distillation (VMD). The main motivation for using VMD in this work is that this module configuration is much simpler and more suitable for this kind of investigation than the other MD configurations such as Direct Contact Membrane Distillation (DCMD). The coupling between heat and mass transfer mechanisms at the feed-membrane interface is presented from a theoretical point of view. In addition, a new simple graphical method and a mathematical model for determining VMD flux are presented. The two methods used in evaluating the extent of temperature polarization effect on water vapor flux (flux sensitivity factors and temperature polarization coefficient (TPC)) are also analyzed and compared. The effect of integrating a heat recovery system in a large scale module on the TPC coefficient has also been studied and presented in this paper. © 2014 Elsevier B.V.

  10. Experimental and theoretical analyses of temperature polarization effect in vacuum membrane distillation

    KAUST Repository

    Alsaadi, Ahmad Salem

    2014-08-13

    This paper discusses the effect of temperature polarization in Vacuum Membrane Distillation (VMD). The main motivation for using VMD in this work is that this module configuration is much simpler and more suitable for this kind of investigation than the other MD configurations such as Direct Contact Membrane Distillation (DCMD). The coupling between heat and mass transfer mechanisms at the feed-membrane interface is presented from a theoretical point of view. In addition, a new simple graphical method and a mathematical model for determining VMD flux are presented. The two methods used in evaluating the extent of temperature polarization effect on water vapor flux (flux sensitivity factors and temperature polarization coefficient (TPC)) are also analyzed and compared. The effect of integrating a heat recovery system in a large scale module on the TPC coefficient has also been studied and presented in this paper. © 2014 Elsevier B.V.

  11. Composite Membrane with Underwater-Oleophobic Surface for Anti-Oil-Fouling Membrane Distillation.

    Science.gov (United States)

    Wang, Zhangxin; Hou, Deyin; Lin, Shihong

    2016-04-05

    In this study, we fabricated a composite membrane for membrane distillation (MD) by modifying a commercial hydrophobic polyvinylidene fluoride (PVDF) membrane with a nanocomposite coating comprising silica nanoparticles, chitosan hydrogel and fluoro-polymer. The composite membrane exhibits asymmetric wettability, with the modified surface being in-air hydrophilic and underwater oleophobic, and the unmodified surface remaining hydrophobic. By comparing the performance of the composite membrane and the pristine PVDF membrane in direct contact MD experiments using a saline emulsion with 1000 ppm crude oil (in water), we showed that the fabricated composite membrane was significantly more resistant to oil fouling compared to the pristine hydrophobic PVDF membrane. Force spectroscopy was conducted for the interaction between an oil droplet and the membrane surface using a force tensiometer. The difference between the composite membrane and the pristine PVDF membrane in their interaction with an oil droplet served to explain the difference in the fouling propensities between these two membranes observed in MD experiments. The results from this study suggest that underwater oleophobic coating can effectively mitigate oil fouling in MD operations, and that the fabricated composite membrane with asymmetric wettability can enable MD to desalinate hypersaline wastewater with high concentrations of hydrophobic contaminants.

  12. Influence of high range of mass transfer coefficient and convection heat transfer on direct contact membrane distillation performance

    KAUST Repository

    Lee, Jung Gil

    2017-11-03

    In order to improve water production of membrane distillation (MD), the development of high performance membrane having better mass transfer and enhancement of convection heat transfer in MD module have been continuously investigated. This paper presents the relationship between the heat and mass transfer resistance across the membrane and the performance improvement. Various ranges of mass transfer coefficient (MTC) from normal (0.3×10−6 to 2.1×10−6kg/m2sPa: currently available membranes) to high (>2.1×10−6kg/m2sPa: membranes under development) were simulated using an experimentally validated model at different ranges of convection heat transfer by varying the inlet flow rates and spacer enhancement factor. The effect of mass transfer and convection heat transfer on the MD performance parameters including temperature polarization coefficient (TPC), mean permeate flux, and specific energy consumption were investigated in a direct contact MD (DCMD) configuration. Results showed that improving the MTC at the low ranges is more important than that at the high ranges where the heat transfer resistance becomes dominant and hence the convection heat transfer coefficient must be increased. Therefore, an effort on designing MD modules using feed and permeate spacers and controlling the membrane surface roughness to increase the convection heat transfer and TPC in the channel aiming to enhance the flux is required because the currently developed mass transfer has almost reached the critical point.

  13. Membrane Distillation of Meat Industry Effluent with Hydrophilic Polyurethane Coated Polytetrafluoroethylene Membranes

    Directory of Open Access Journals (Sweden)

    M. G. Mostafa

    2017-09-01

    Full Text Available Meat rendering operations produce stick water waste which is rich in proteins, fats, and minerals. Membrane distillation (MD may further recover water and valuable solids, but hydrophobic membranes are contaminated by the fats. Here, commercial hydrophobic polytetrafluorethylene (PTFE membranes with a hydrophilic polyurethane surface layer (PU-PTFE are used for the first time for direct contact MD (DCMD on real poultry, fish, and bovine stick waters. Metal membrane microfiltration (MMF was also used to capture fats prior to MD. Although the standard hydrophobic PTFE membranes failed rapidly, PU-PTFE membranes effectively processed all stick water samples to colourless permeate with sodium rejections >99%. Initial clean solution fluxes 5–6 L/m2/h declined to less than half during short 40% water recovery tests for all stick water samples. Fish stick water uniquely showed reduced fouling and up to 78% water recovery. Lost flux was easily restored by rinsing the membrane with clean water. MMF prior to MD removed 92% of fats, facilitating superior MD performance. Differences in fouling between stick waters were attributed to temperature polarisation from higher melt temperature fats and relative proportions to proteins. Hydrophilic coated MD membranes are applicable to stick water processing but further studies should consider membrane cleaning and longer-term stability.

  14. Membrane Distillation of Meat Industry Effluent with Hydrophilic Polyurethane Coated Polytetrafluoroethylene Membranes.

    Science.gov (United States)

    Mostafa, M G; Zhu, Bo; Cran, Marlene; Dow, Noel; Milne, Nicholas; Desai, Dilip; Duke, Mikel

    2017-09-29

    Meat rendering operations produce stick water waste which is rich in proteins, fats, and minerals. Membrane distillation (MD) may further recover water and valuable solids, but hydrophobic membranes are contaminated by the fats. Here, commercial hydrophobic polytetrafluorethylene (PTFE) membranes with a hydrophilic polyurethane surface layer (PU-PTFE) are used for the first time for direct contact MD (DCMD) on real poultry, fish, and bovine stick waters. Metal membrane microfiltration (MMF) was also used to capture fats prior to MD. Although the standard hydrophobic PTFE membranes failed rapidly, PU-PTFE membranes effectively processed all stick water samples to colourless permeate with sodium rejections >99%. Initial clean solution fluxes 5-6 L/m²/h declined to less than half during short 40% water recovery tests for all stick water samples. Fish stick water uniquely showed reduced fouling and up to 78% water recovery. Lost flux was easily restored by rinsing the membrane with clean water. MMF prior to MD removed 92% of fats, facilitating superior MD performance. Differences in fouling between stick waters were attributed to temperature polarisation from higher melt temperature fats and relative proportions to proteins. Hydrophilic coated MD membranes are applicable to stick water processing but further studies should consider membrane cleaning and longer-term stability.

  15. Control of distributed heat transfer mechanisms in membrane distillation plants

    KAUST Repository

    Laleg-Kirati, Taous-Meriem; Eleiwi, Fadi; Karam, Ayman M.

    2017-01-01

    Various examples are provided that are related to boundary control in membrane distillation (MD) processes. In one example, a system includes a membrane distillation (MD) process comprising a feed side and a permeate side separated by a membrane

  16. Attainability and minimum energy of single-stage membrane and membrane/distillation hybrid processes

    KAUST Repository

    Alshehri, Ali

    2014-12-01

    As an energy-efficient separation method, membrane technology has attracted more and more attentions in many challenging separation processes. The attainability and the energy consumption of a membrane process are the two basic fundamental questions that need to be answered. This report aims to use process simulations to find: (1) at what conditions a single-stage membrane process can meet the separation task that is defined by product purity and recovery ratio and (2) what are the most important parameters that determine the energy consumption. To perform a certain separation task, it was found that both membrane selectivity and pressure ratio exhibit a minimum value that is defined only by product purity and recovery ratio. The membrane/distillation hybrid system was used to study the energy consumption. A shortcut method was developed to calculate the minimum practical separation energy (MPSE) of the membrane process and the distillation process. It was found that the MPSE of the hybrid system is only determined by the membrane selectivity and the applied transmembrane pressure ratio in three stages. At the first stage when selectivity is low, the membrane process is not competitive to the distillation process. Adding a membrane unit to a distillation tower will not help in reducing energy. At the second medium selectivity stage, the membrane/distillation hybrid system can help reduce the energy consumption, and the higher the membrane selectivity, the lower is the energy. The energy conservation is further improved as pressure ratio increases. At the third stage when both selectivity and pressure ratio are high, the hybrid system will change to a single-stage membrane unit and this change will cause significant reduction in energy consumption. The energy at this stage keeps decreasing with selectivity at slow rate, but slightly increases with pressure ratio. Overall, the higher the membrane selectivity, the more the energy is saved. Therefore, the two

  17. Vapor compression distiller and membrane technology for water revitalization

    Science.gov (United States)

    Ashida, A.; Mitani, K.; Ebara, K.; Kurokawa, H.; Sawada, I.; Kashiwagi, H.; Tsuji, T.; Hayashi, S.; Otsubo, K.; Nitta, K.

    1987-01-01

    Water revitalization for a space station can consist of membrane filtration processes and a distillation process. Water recycling equipment using membrane filtration processes was manufactured for ground testing. It was assembled using commercially available components. Two systems for the distillation are studied: one is absorption type thermopervaporation cell and the other is a vapor compression distiller. Absorption type thermopervaporation, able to easily produce condensed water under zero gravity, was investigated experimentally and through simulated calculation. The vapor compression distiller was studied experimentally and it offers significant energy savings for evaporation of water.

  18. Effect of dope solution temperature on the membrane structure and membrane distillation performance

    Science.gov (United States)

    Nawi, N. I. M.; Bilad, M. R.; Nordin, N. A. H. M.

    2018-04-01

    Membrane distillation (MD) is a non-isothermal process applicable to purify water using hydrophobic membrane. Membrane in MD is hydrophobic, permeable to water vapor but repels liquid water. MD membrane is expected to pose high flux, high fouling and scaling resistances and most importantly high wetting resistance. This study develops flat-sheet polyvinylidene fluoride (PVDF) membrane by exploring both liquid-liquid and liquid-solid phase inversion technique largely to improve its wetting resistance and flux performance. We hypothesize that temperature of dope solution play roles in solid-liquid separation during membrane formation and an optimum balance between liquid-liquid and liquid-solid (crystallization) separation leads to highly performance PVDF membrane. Findings obtained from differential scanning calorimeter test show that increasing dope solution temperature reduces degree of PVDF crystallinity and suppresses formation of crystalline structure. The morphological images of the resulting membranes show that at elevated dope solution temperature (40, 60, 80 and 100°C), the spherulite-like structures are formed across the thickness of membranes ascribed from due to different type of crystals. The performance of direct-contact MD shows that the obtained flux of the optimum dope temperature (60°C) of 10.8 L/m2h is comparable to commercial PTFE-based MD membrane.

  19. Tri-bore PVDF hollow fibers with a super-hydrophobic coating for membrane distillation

    KAUST Repository

    Lu, Kang-Jia; Zuo, Jian; Chung, Tai-Shung

    2016-01-01

    Membranes with good mechanical strength, high vapor flux and outstanding anti-wetting properties are essential for membrane distillation (MD) applications. In this work, porous polyvinylidene fluoride (PVDF) tri-bore hollow fiber membranes with super-hydrophobicity are developed to achieve these desired properties. The tri-bore hollow fiber offers better mechanical strength than the conventional single-bore fiber. To improve its anti-wetting properties, Teflon® AF 2400 is coated on the membrane surface. The effects of coating on membrane morphology, performance and anti-wetting properties have been thoroughly investigated. With an optimal coating condition (0.025 wt% of Teflon® AF 2400, 30 s), a super-hydrophobic surface with a contact angle of 151o is achieved. The resultant membrane shows an increase of 109% in liquid entry pressure (LEP) with a slight sacrifice of 21% in flux. Long term direct contact MD tests have confirmed that the Teflon® AF 2400 coated membrane has enhanced stability with an average flux of 21 kg m-2 h-1 and rejection of 99.99% at 60 °° C for desalination application.

  20. Tri-bore PVDF hollow fibers with a super-hydrophobic coating for membrane distillation

    KAUST Repository

    Lu, Kang-Jia

    2016-04-26

    Membranes with good mechanical strength, high vapor flux and outstanding anti-wetting properties are essential for membrane distillation (MD) applications. In this work, porous polyvinylidene fluoride (PVDF) tri-bore hollow fiber membranes with super-hydrophobicity are developed to achieve these desired properties. The tri-bore hollow fiber offers better mechanical strength than the conventional single-bore fiber. To improve its anti-wetting properties, Teflon® AF 2400 is coated on the membrane surface. The effects of coating on membrane morphology, performance and anti-wetting properties have been thoroughly investigated. With an optimal coating condition (0.025 wt% of Teflon® AF 2400, 30 s), a super-hydrophobic surface with a contact angle of 151o is achieved. The resultant membrane shows an increase of 109% in liquid entry pressure (LEP) with a slight sacrifice of 21% in flux. Long term direct contact MD tests have confirmed that the Teflon® AF 2400 coated membrane has enhanced stability with an average flux of 21 kg m-2 h-1 and rejection of 99.99% at 60 °° C for desalination application.

  1. Metal–Organic Framework-Functionalized Alumina Membranes for Vacuum Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Jian Zuo

    2016-12-01

    Full Text Available Nature-mimetic hydrophobic membranes with high wetting resistance have been designed for seawater desalination via vacuum membrane distillation (VMD in this study. This is achieved through molecular engineering of metal–organic framework (MOF-functionalized alumina surfaces. A two-step synthetic strategy was invented to design the hydrophobic membranes: (1 to intergrow MOF crystals on the alumina tube substrate and (2 to introduce perfluoro molecules onto the MOF functionalized membrane surface. With the first step, the surface morphology, especially the hierarchical roughness, can be controlled by tuning the MOF crystal structure. After the second step, the perfluoro molecules function as an ultrathin layer of hydrophobic floss, which lowers the surface energy. Therefore, the resultant membranes do not only possess the intrinsic advantages of alumina supports such as high stability and high water permeability, but also have a hydrophobic surface formed by MOF functionalization. The membrane prepared under an optimum condition achieved a good VMD flux of 32.3 L/m2-h at 60 °C. This study may open up a totally new approach for design of next-generation high performance membrane distillation membranes for seawater desalination.

  2. Membrane distillation for wastewater reverse osmosis concentrate treatment with water reuse potential

    KAUST Repository

    Naidu, Gayathri; Jeong, Sanghyun; Choi, Youngkwon; Vigneswaran, Saravanamuthu

    2016-01-01

    Membrane distillation (MD) was evaluated as a treatment option of wastewater reverse osmosis concentrate (WWROC) discharged from wastewater reclamation plants (WRPs). A direct contact MD (DCMD), at obtaining 85% water recovery of WWROC showed only 13–15% flux decline and produced good quality permeate (10–15 µS/cm, 99% ion rejection) at moderate feed temperature of 55 °C. Prevalent calcium carbonate (CaCO3) deposition on the MD membrane occurred in treating WWROC at elevated concentrations. The combination of low salinity and loose CaCO3 adhesion on the membrane did not significantly contribute to DCMD flux decline. Meanwhile, high organic content in WWROC (58–60 mg/L) resulted in a significant membrane hydrophobicity reduction (70% lower water contact angle than virgin membrane) attributed to low molecular weight organic adhesion onto the MD membrane. Granular activated carbon (GAC) pretreatment helped in reducing organic contents of WWROC by 46–50%, and adsorbed a range of hydrophobic and hydrophilic micropollutants. This ensured high quality water production by MD (micropollutants-free) and enhanced its reuse potential. The MD concentrated WWROC was suitable for selective ion precipitation, promising a near zero liquid discharge in WRPs.

  3. Membrane distillation for wastewater reverse osmosis concentrate treatment with water reuse potential

    KAUST Repository

    Naidu, Gayathri

    2016-11-29

    Membrane distillation (MD) was evaluated as a treatment option of wastewater reverse osmosis concentrate (WWROC) discharged from wastewater reclamation plants (WRPs). A direct contact MD (DCMD), at obtaining 85% water recovery of WWROC showed only 13–15% flux decline and produced good quality permeate (10–15 µS/cm, 99% ion rejection) at moderate feed temperature of 55 °C. Prevalent calcium carbonate (CaCO3) deposition on the MD membrane occurred in treating WWROC at elevated concentrations. The combination of low salinity and loose CaCO3 adhesion on the membrane did not significantly contribute to DCMD flux decline. Meanwhile, high organic content in WWROC (58–60 mg/L) resulted in a significant membrane hydrophobicity reduction (70% lower water contact angle than virgin membrane) attributed to low molecular weight organic adhesion onto the MD membrane. Granular activated carbon (GAC) pretreatment helped in reducing organic contents of WWROC by 46–50%, and adsorbed a range of hydrophobic and hydrophilic micropollutants. This ensured high quality water production by MD (micropollutants-free) and enhanced its reuse potential. The MD concentrated WWROC was suitable for selective ion precipitation, promising a near zero liquid discharge in WRPs.

  4. Control of distributed heat transfer mechanisms in membrane distillation plants

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-01-05

    Various examples are provided that are related to boundary control in membrane distillation (MD) processes. In one example, a system includes a membrane distillation (MD) process comprising a feed side and a permeate side separated by a membrane boundary layer; and processing circuitry configured to control a water production rate of the MD process based at least in part upon a distributed heat transfer across the membrane boundary layer. In another example, a method includes determining a plurality of estimated temperature states of a membrane boundary layer separating a feed side and a permeate side of a membrane distillation (MD) process; and adjusting inlet flow rate or inlet temperature of at least one of the feed side or the permeate side to maintain a difference temperature along the membrane boundary layer about a defined reference temperature based at least in part upon the plurality of estimated temperature states.

  5. Memstill® - Low cost membrane distillation technology for seawater desalination

    NARCIS (Netherlands)

    Hanemaaijer, J.H.

    2004-01-01

    Despite widespread research and development efforts during the last 25 years, membrane distillation still is not an accepted process for seawater desalination. A consortium of nine parties is presently developing a modified air gap membrane distillation (AGMD) process, aiming at presenting a

  6. Carbon nanotube embedded PVDF membranes: Effect of solvent composition on the structural morphology for membrane distillation

    Science.gov (United States)

    Mapunda, Edgar C.; Mamba, Bhekie B.; Msagati, Titus A. M.

    2017-08-01

    Rapid population increase, growth in industrial and agricultural sectors and global climate change have added significant pressure on conventional freshwater resources. Tapping freshwater from non-conventional water sources such as desalination and wastewater recycling is considered as sustainable alternative to the fundamental challenges of water scarcity. However, affordable and sustainable technologies need to be applied for the communities to benefit from the treatment of non-conventional water source. Membrane distillation is a potential desalination technology which can be used sustainably for this purpose. In this work multi-walled carbon nanotube embedded polyvinylidene fluoride membranes for application in membrane distillation desalination were prepared via non-solvent induced phase separation method. The casting solution was prepared using mixed solvents (N, N-dimethylacetamide and triethyl phosphate) at varying ratios to study the effect of solvent composition on membrane morphological structures. Membrane morphological features were studied using a number of techniques including scanning electron microscope, atomic force microscope, SAXSpace tensile strength analysis, membrane thickness, porosity and contact angle measurements. It was revealed that membrane hydrophobicity, thickness, tensile strength and surface roughness were increasing as the composition of N, N-dimethylacetamide in the solvent was increasing with maximum values obtained between 40 and 60% N, N-dimethylacetamide. Internal morphological structures were changing from cellular structures to short finger-like and sponge-like pores and finally to large macro void type of pores when the amount of N, N-dimethylacetamide in the solvent was changed from low to high respectively. Multi-walled carbon nanotube embedded polyvinylidene fluoride membranes of desired morphological structures and physical properties can be synthesized by regulating the composition of solvents used to prepare the

  7. Material gap membrane distillation: A new design for water vapor flux enhancement

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Amy, Gary L.

    2013-01-01

    A new module design for membrane distillation, namely material gap membrane distillation (MGMD), for seawater desalination has been proposed and successfully tested. It has been observed that employing appropriate materials between the membrane

  8. Electrospun superhydrophobic membranes with unique structures for membrane distillation.

    Science.gov (United States)

    Liao, Yuan; Loh, Chun-Heng; Wang, Rong; Fane, Anthony G

    2014-09-24

    With modest temperature demand, low operating pressure, and high solute rejection, membrane distillation (MD) is an attractive option for desalination, waste treatment, and food and pharmaceutical processing. However, large-scale practical applications of MD are still hindered by the absence of effective membranes with high hydrophobicity, high porosity, and adequate mechanical strength, which are important properties for MD permeation fluxes, stable long-term performance, and effective packing in modules without damage. This study describes novel design strategies for highly robust superhydrophobic dual-layer membranes for MD via electrospinning. One of the newly developed membranes comprises a durable and ultrathin 3-dimensional (3D) superhydrophobic skin and porous nanofibrous support whereas another was fabricated by electrospinning 3D superhydrophobic layers on a nonwoven support. These membranes exhibit superhydrophobicity toward distilled water, salty water, oil-in-water emulsion, and beverages, which enables them to be used not only for desalination but also for other processes. The superhydrophobic dual-layer membrane #3S-N with nanofibrous support has a competitive permeation flux of 24.6 ± 1.2 kg m(-2) h(-1) in MD (feed and permeate temperate were set as 333 and 293 K, respectively) due to the higher porosity of the nanofibrous scaffold. Meanwhile, the membranes with the nonwoven support exhibit greater mechanical strength due to this support combined with better long-term performance because of the thicker 3D superhydrophobic layers. The morphology, pore size, porosity, mechanical properties, and liquid enter pressure of water of these superhydrophobic composite membranes with two different structures are reported and compared with commercial polyvinylidene fluoride membranes.

  9. Fouling mechanisms of dairy streams during membrane distillation

    NARCIS (Netherlands)

    Hausmann, A.; Sanciolo, P.; Vasiljevic, T.; Weeks, M.; Schroën, C.G.P.H.; Gray, S.; Duke, M.

    2013-01-01

    This study reports on fouling mechanisms of skim milk and whey during membrane distillation (MD) using polytetrafluoroethylene (PTFE) membranes. Structural and elemental changes along the fouling layer from the anchorpoint at the membrane to the topsurface of the fouling layer have been investigated

  10. Ocean thermocline driven membrane distillation process

    KAUST Repository

    Francis, Lijo

    2017-07-20

    Systems and methods using membrane distillation are provided for desalinating water, for example for the production of potable water, to address freshwater requirements. In an aspect the systems and methods do not require applying an external heat source, or the energy cost of the heating source, to heat the feed stream to the membrane. In an aspect, the sensible heat present in surface seawater is used for the heat energy for the warm stream fed to the membrane, and deep seawater is used as the cold/coolant feed to the membrane to provide the needed temperature gradient or differential across the membrane.

  11. Membrane distillation of industrial cooling tower blowdown water

    Directory of Open Access Journals (Sweden)

    N.E. Koeman-Stein

    2016-06-01

    Full Text Available The potential of membrane distillation for desalination of cooling tower blowdown water (CTBD is investigated. Technical feasibility is tested on laboratory and pilot scale using real cooling tower blowdown water from Dow Benelux in Terneuzen (Netherlands. Two types of membranes, polytetrafluorethylene and polyethylene showed good performance regarding distillate quality and fouling behavior. Concentrating CTBD by a factor 4.5 while maintaining a flux of around 2 l/m2*h was possible with a water recovery of 78% available for reuse. Higher concentration factors lead to severe decrease in flux which was caused by scaling. Membrane distillation could use the thermal energy that would otherwise be discharged of in a cooling tower and function as a heat exchanger. This reduces the need for cooling capacity and could lead to a total reduction of 37% water intake for make-up water, as well as reduced energy and chemicals demands and greenhouse gas emissions.

  12. Increasing the Performance of Vacuum Membrane Distillation Using Micro-Structured Hydrophobic Aluminum Hollow Fiber Membranes

    Directory of Open Access Journals (Sweden)

    Chia-Chieh Ko

    2017-04-01

    Full Text Available This study develops a micro-structured hydrophobic alumina hollow fiber with a high permeate flux of 60 Lm−2h−1 and salt rejection over 99.9% in a vacuum membrane distillation process. The fiber is fabricated by phase inversion and sintering, and then modified with fluoroalkylsilanes to render it hydrophobic. The influence of the sintering temperature and feeding temperature in membrane distillation (MD on the characteristics of the fiber and MD performance are investigated. The vacuum membrane distillation uses 3.5 wt % NaCl aqueous solution at 70 °C at 0.03 bar. The permeate flux of 60 Lm−2h−1 is the highest, compared with reported data and is higher than that for polymeric hollow fiber membranes.

  13. PDMS/PVDF hybrid electrospun membrane with superhydrophobic property and drop impact dynamics for dyeing wastewater treatment using membrane distillation

    KAUST Repository

    An, Alicia Kyoungjin

    2016-10-21

    Fouling in membrane distillation (MD) results in an increase in operation costs and deterioration in a water quality. In this work, a poly(vinylidene fluoride-co-hexafluoropropene) (PVDF-HFP) electrospun (E-PH) membrane was fabricated by hybridizing polydimethylsiloxane (PDMS) polymeric microspheres with superhydrophobicity onto the E-PH membrane via electrospinning. The resulting hybrid PDMS with E-PH (E-PDMS) membrane showed a significant enhancement in surface hydrophobicity (contact angle, CA = 155.4°) and roughness (Ra = 1,285mm). The zeta potential of E-PDMS membrane surface showed a higher negative value than that of a commercial PVDF (C-PVDF) membrane. These properties of E-PDMS membrane provided an antifouling in treating of differently-charged dyes and generated a flake-like dye–dye (loosely bound foulant) structure on the membrane surface rather than in the membrane pores. This also led to a high productivity of E-PDMS membrane (34 Lm-2h-1, 50% higher than that of C-PVDF membrane) without fouling or wetting. In addition, complete color removal and pure water production were achieved during a long-term operation. An application of intermittent water flushing (WF) in direct contact MD (DCMD) operation led to a 99% CA recovery of E-PDMS membrane indicating its sustainability. Therefore, the E-PDMS membrane is a promising candidate for MD application in dyeing wastewater treatment.

  14. Sweep gas membrane distillation in a membrane contactor with metallic hollow fibers

    NARCIS (Netherlands)

    Shukla, Sushumna; Benes, Nieck Edwin; Vankelecom, I.F.J.; Mericq, J.P.; Belleville, M.P.; Hengl, N.; Sanchez Marcano, Jose

    2015-01-01

    This work revolves around the use of porous metal hollow fibers in membrane distillation. Various stages are covered, starting from membrane synthesis up to the testing of a pilot scale membrane module. Mechanically stable metal hollow fibers have been synthesized by phase inversion of a stainless

  15. Dynamic solar-powered multi-stage direct contact membrane distillation system: Concept design, modeling and simulation

    KAUST Repository

    Lee, Jung Gil

    2017-04-26

    This paper presents a theoretical analysis of the monthly average daily and hourly performances of a solar-powered multi-stage direct contact membrane distillation (SMDCMD) system with an energy recovery scheme and dynamic operating system. Mid-latitude meteorological data from Busan, Korea is employed, featuring large climate variation over the course of one year. The number of module stages used by the dynamic operating scheme changes dynamically based on the inlet feed temperature of the successive modules, which results in an improvement of the water production and thermal efficiency. The simulations of the SMDCMD system are carried out to investigate the spatial and temporal variations in the feed and permeate temperatures and permeate flux. The monthly average daily water production increases from 0.37m3/day to 0.4m3/day and thermal efficiency increases from 31% to 45% when comparing systems both without and with dynamic operation in December. The water production with respect to collector area ranged from 350m2 to 550m2 and the seawater storage tank volume ranged from 16m3 to 28.8m3, and the solar fraction at various desired feed temperatures from 50°C to 80°C have been investigated in October and December.

  16. Molecular Grafting of Fluorinated and Nonfluorinated Alkylsiloxanes on Various Ceramic Membrane Surfaces for the Removal of Volatile Organic Compounds Applying Vacuum Membrane Distillation.

    Science.gov (United States)

    Kujawa, Joanna; Al-Gharabli, Samer; Kujawski, Wojciech; Knozowska, Katarzyna

    2017-02-22

    Four main tasks were presented: (i) ceramic membrane functionalization (TiO 2 5 kDa and 300 kDa), (ii) extended material characterization (physicochemistry and tribology) of pristine and modified ceramic samples, (iii) evaluation of chemical and mechanical stability, and finally (iv) assessment of membrane efficiency in vacuum membrane distillation applied for volatile organic compounds (VOCs) removal from water. Highly efficient molecular grafting with four types of perfluoroalkylsilanes and one nonfluorinated agent was developed. Materials with controllable tribological and physicochemical properties were achieved. The most meaningful finding is associated with the applicability of fluorinated and nonfluorinated grafting agents. The results of contact angle, hysteresis of contact angle, sliding angle, and critical surface tension as well as Young's modulus, nanohardness, and adhesion force for grafting by these two modifiers are comparable. This provides insight into the potential applicability of environmental friendly hydrophobic and superhydrophobic surfaces. The achieved hydrophobic membranes were very effective in the removal of VOCs (butanol, methyl-tert-butyl ether, and ethyl acetate) from binary aqueous solutions in vacuum membrane distillation. The correlation between membrane effectiveness and separated solvent polarity was compared in terms of material properties and resistance to the wetting (kinetics of wetting and in-depth liquid penetration). Material properties were interpreted considering Zisman theory and using Kao diagram. The significant influence of surface chemistry on the membrane performance was noticed (5 kDa, influence of hydrophobic nanolayer and separation controlled by solution-diffusion model; 300 kDa, no impact of surface chemistry and separation controlled by liquid-vapor equilibrium).

  17. On the heat transfer correlation for membrane distillation

    International Nuclear Information System (INIS)

    Wang, Chi-Chuan

    2011-01-01

    Research highlights: → Heat transfer coefficients applicable for membrane distillation. → Data reduction for heat transfer coefficient for membrane distillation method. → Uncertainty of permeate side due to large magnitude of membrane resistance. → Increase accuracy of heat transfer coefficient by modified Wilson plot technique. -- Abstract: The present study examines the heat transfer coefficients applicable for membrane distillation. In the available literatures, researchers often adopt some existing correlations and claim the suitability of these correlations to their test data or models. Unfortunately this approach is quite limited and questionable. This is subject to the influences of boundary conditions, geometrical configurations, entry flow conditions, as well as some influences from spacer or support. The simple way is to obtain the heat transfer coefficients from experimentation. However there is no direct experimental data for heat transfer coefficients being reported directly from the measurements. The main reasons are from the uncertainty of permeate side and of the comparatively large magnitude of membrane resistance. Additional minor influence is the effect of mass transfer on the heat transfer performance. In practice, the mass transfer effect is negligible provided the feed side temperature is low. To increase the accuracy of the measured feed side heat transfer coefficient, it is proposed in this study to exploit a modified Wilson plot technique. Through this approach, one can eliminate the uncertainty from permeate side and reduce the uncertainty in membrane to obtain a more reliable heat transfer coefficients at feed side from the experimentation.

  18. Total water production capacity inversion phenomenon in multi-stage direct contact membrane distillation: A theoretical study

    KAUST Repository

    Lee, Jung Gil

    2017-09-09

    The low thermal efficiency and low water production are among the major challenges that prevent membrane distillation (MD) process from being commercialized. In an effort to design an efficient multi-stage direct contact MD (DCMD) unit through mathematical simulation, a new phenomenon that we refer to as total water production capacity inversion (WPI) has been detected. It is represented by a decrease in the total water production beyond a number of stages or a certain module length. WPI phenomenon, which was confirmed by using two different mathematical models validated experimentally, was found to take place due to the decrease in water vapor flux across the membrane as well as the increase in heat loss by conduction as the membrane length increases. Therefore, WPI should be considered as a critical MD design-criterion, especially for large scale units. Investigations conducted for a simulated multi-stage DCMD process showed that inlet feed and permeate temperatures difference, feed and permeate flow rates, and feed salinity have different effects on WPI. The number of stages (or module length at constant width) that leads to a maximum water production has been determined for different operating parameters. Decreasing inlet feed and permeate temperatures difference, or inlet feed and permeate flow rates and increasing inlet feed temperature at constant temperature difference or inlet feed salinity cause the WPI to take place at lower number of stages. Even though the feed salinity affects negligibly the mean permeate flux, it was clearly shown that it can affect WPI. The results presented herein unveil a hidden phenomenon that is likely to occur during process scale-up procedures and should be considered by process engineers for a proper choice of system design and operating conditions.

  19. Development of hydrophobic clay–alumina based capillary membrane for desalination of brine by membrane distillation

    Directory of Open Access Journals (Sweden)

    Rakhi Das

    2016-09-01

    Full Text Available Clay–alumina compositions of 0, 20, 40 and 55 weight percent (wt% clay and rest alumina were maintained in porous support preparation by extrusion followed by sintering at 1300 °C for 2.5 h to obtain 3 mm/2 mm (outer diameter/inner diameter capillary. 1H,1H,2H,2H-perfluorodecyltriethoxysilane (97% (C8 was used to modify the capillary surface of all compositions without any intermediate membrane layer to impart hydrophobic characteristics and compared in terms of contact angle produced by the capillaries with water and liquid entry pressure (LEPw. FTIR analysis showed that the hydrophilic surface of the capillary membranes was efficiently modified by the proposed grafting method. Capillary with 55 wt% clay produced a pore size of 1.43 micron and was considered as an ideal candidate for grafting with C8 polymer to impart surface hydrophobicity. The contact angle and LEPw value obtained for this modified membrane (C-55-M were 145° and 1 bar, respectively. The modified capillary membrane was applied for desalination of brine by air gap membrane distillation (AGMD at a feed pressure of 0.85 bar. Maximum flux obtained for C-55-M membrane was 98.66 L/m2 day at a temperature difference of 60 °C with salt rejection of 99.96%. Mass transfer coefficient of C-55-M was 16 × 10−3 mm/s at feed temperature of 70 °C.

  20. Soft sensing of system parameters in membrane distillation

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-01-01

    Various examples of methods and systems are provided for soft sensing of system parameters in membrane distillation (MD). In one example, a system includes a MD module comprising a feed side and a permeate side separated by a membrane boundary layer

  1. Wetting Resistance of Commercial Membrane Distillation Membranes in Waste Streams Containing Surfactants and Oil

    Directory of Open Access Journals (Sweden)

    Lies Eykens

    2017-01-01

    Full Text Available Water management is becoming increasingly challenging and several technologies, including membrane distillation (MD are emerging. This technology is less affected by salinity compared to reverse osmosis and is able to treat brines up to saturation. The focus of MD research recently shifted from seawater desalination to industrial applications out of the scope of reverse osmosis. In many of these applications, surfactants or oil traces are present in the feed stream, lowering the surface tension and increasing the risk for membrane wetting. In this study, the technological boundaries of MD in the presence of surfactants are investigated using surface tension, contact angle and liquid entry pressure measurements together with lab-scale MD experiments to predict the wetting resistance of different membranes. Synthetic NaCl solutions mixed with sodium dodecyl sulfate (SDS were used as feed solution. The limiting surfactant concentration was found to be dependent on the surface chemistry of the membrane, and increased with increasing hydrophobicity and oleophobicity. Additionally, a hexadecane/SDS emulsion was prepared with a composition simulating produced water, a waste stream in the oil and gas sector. When hexadecane is present in the emulsion, oleophobic membranes are able to resist wetting, whereas polytetrafluoretheen (PTFE is gradually wetted by the feed liquid.

  2. High flux and antifouling properties of negatively charged membrane for dyeing wastewater treatment by membrane distillation

    KAUST Repository

    An, Alicia Kyoungjin

    2016-07-25

    This study investigated the applicability of membrane distillation (MD) to treat dyeing wastewater discharged by the textile industry. Four different dyes containing methylene blue (MB), crystal violet (CV), acid red 18 (AR), and acid yellow 36 (AY) were tested. Two types of hydrophobic membranes made of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) were used. The membranes were characterized by testing against each dye (foulant-foulant) and the membrane–dye (membrane-foulant) interfacial interactions and their mechanisms were identified. The MD membranes possessed negative charges, which facilitated the treatment of acid and azo dyes of the same charge and showed higher fluxes. In addition, PTFE membrane reduced the wettability with higher hydrophobicity of the membrane surface. The PTFE membrane evidenced especially its resistant to dye absorption, as its strong negative charge and chemical structure caused a flake-like (loose) dye–dye structure to form on the membrane surface rather than in the membrane pores. This also enabled the recovery of flux and membrane properties by water flushing (WF), thereby direct-contact MD with PTFE membrane treating 100 mg/L of dye mixtures showed stable flux and superior color removal during five days operation. Thus, MD shows a potential for stable long-term operation in conjunction with a simple membrane cleaning process, and its suitability in dyeing wastewater treatment.

  3. Degradation of Polypropylene Membranes Applied in Membrane Distillation Crystallizer

    Directory of Open Access Journals (Sweden)

    Marek Gryta

    2016-03-01

    Full Text Available The studies on the resistance to degradation of capillary polypropylene membranes assembled in a membrane crystallizer were performed. The supersaturation state of salt was achieved by evaporation of water from the NaCl saturated solutions using membrane distillation process. A high feed temperature (363 K was used in order to enhance the degradation effects and to shorten the test times. Salt crystallization was carried out by the application of batch or fluidized bed crystallizer. A significant membrane scaling was observed regardless of the method of realized crystallization. The SEM-EDS, DSC, and FTIR methods were used for investigations of polypropylene degradation. The salt crystallization onto the membrane surface accelerated polypropylene degradation. Due to a polymer degradation, the presence of carbonyl groups on the membranes’ surface was identified. Besides the changes in the chemical structure a significant mechanical damage of the membranes, mainly caused by the internal scaling, was also found. As a result, the membranes were severely damaged after 150 h of process operation. A high level of salt rejection was maintained despite damage to the external membrane surface.

  4. Treatment of uranium-bearing wastewater by vacuum membrane distillation

    International Nuclear Information System (INIS)

    Duan Xiaolin; Li Qicheng; Chen Bingbing

    2006-01-01

    The removal of uranium from wastewater was carried out by vacuum membrane distillation (VMD) using microporous polypropylene membrane. The effects of feed temperature, mass concentration of U, flow rate and vacuum-side pressure on permeation flux and rejection were studied. The optimum experimental conditions are as follows: feed flow rate is 0.5 m/s, feed temperature is 55 degree C, vacuum-side pressure is 2.66 kPa. When the mass concentrations of U in the feed solution range from 1 mg/L to 9 mg/L, the membrane flux is 3.5 kg/(m 2 ·h) and the rejection rate is 99.1% under the optimum conditions. The water separated from uranium solution by vacuum membrane distillation could meet the state-controlled discharge standard 0.05 mg/L. The VMD as a novel technology will play an important role in the treatment of uranium-bearing wastewater. (authors)

  5. Simulation study of transfer characteristics for spacer-filled membrane distillation desalination modules

    International Nuclear Information System (INIS)

    Chang, Hsuan; Hsu, Jian-An; Chang, Cheng-Liang; Ho, Chii-Dong; Cheng, Tung-Wen

    2017-01-01

    Highlights: • A 3D CFD model takes in transmembrane heat and mass transfer developed. • DCMD modules using spacer-filled and empty channels for desalination simulated. • Fluid flow, heat transfer and mass transfer profiles revealed. • Correlations of friction factor and Nusselt number developed. - Abstract: Membrane distillation (MD) is an emerging and promising membrane separation process, which can directly utilize renewable thermal energy or low-grade waste heat, for applications in water or wastewater treatment and food industry. However, a major drawback of MD process is its low energy efficiency. Spacer is the most suggested and studied eddy promoter to enhance the heat and mass transfer, which further improves both the separation and the energy utilization performance, of MD processes. This paper presents the results of a 3D computational fluid dynamics (CFD) simulation of DCMD (direct contact membrane distillation) modules using channels with and without spacers for desalination application. The model employs permeable wall boundary condition to take into account the transmembrane heat and mass transfer and simulates the entire module length. The simulation reveals similar fluctuating distributions of temperature polarization coefficient, transmembrane heat and mass fluxes as well as the shear stress on the membrane surface along the entire module length. Correlations have been developed for friction factor and average Nusselt number. These correlations are useful for the analysis and design of DCMD modules. The extent of heat transfer enhancement by spacers depends on the geometry of spacers and the Reynolds number of fluid.

  6. EVALUATION OF SODIUM CHLORIDE CRYSTALLIZATION IN MEMBRANE DISTILLATION CRYSTALLIZATION APPLIED TO WATER DESALINATION

    Directory of Open Access Journals (Sweden)

    Y. N. Nariyoshi

    Full Text Available Abstract Crystallization in a Direct Contact Membrane Distillation (DCMD process was studied both theoretically and experimentally. A mathematical model was proposed in order to predict the transmembrane flux in DCMD. The model fitted well experimental data for the system NaCl-H2O from undersaturated to supersaturated conditions in a specially designed crystallization setup at a bench scale. It was found that higher transmembrane fluxes induce higher temperature and concentration polarizations, as well as higher supersaturation in the vicinity of the solution-vapor interface. In this region, the supersaturation ratio largely exceeded the metastable limit for NaCl crystallization for the whole range of transmembrane fluxes of 0.37 to 1.54 kg/ (m2 h, implying that heterogeneous primary nucleation occurred close to such interface either in solution or on the membrane surface. Solids formed in solution accounted for 14 to 36% of the total solids, whereas solid formed on the membrane surface (fouling was responsible for 6 to 19%. The remaining solids deposited on other surfaces such as in pumps and pipe fittings. It was also discovered that, by increasing the supersaturation ratio, heterogeneous nucleation in solution increased and on the membrane surface decreased. Heterogeneous nuclei in solution grew in size both by a molecular mechanism and by agglomeration. Single crystals were cubic shaped with well-formed edges and dominant size of about 40 µm whereas agglomerates were about 240 µm in size. The approach developed here may be applied to understanding crystallization phenomena in Membrane Distillation Crystallization (MDC processes of any scale.

  7. Integrated forward osmosis-membrane distillation process for human urine treatment.

    Science.gov (United States)

    Liu, Qianliang; Liu, Caihong; Zhao, Lei; Ma, Weichao; Liu, Huiling; Ma, Jun

    2016-03-15

    This study demonstrated a forward osmosis-membrane distillation (FO-MD) hybrid system for real human urine treatment. A series of NaCl solutions at different concentrations were adopted for draw solutions in FO process, which were also the feed solutions of MD process. To establish a stable and continuous integrated FO-MD system, individual FO process with different NaCl concentrations and individual direct contact membrane distillation (DCMD) process with different feed temperatures were firstly investigated separately. Four stable equilibrium conditions were obtained from matching the water transfer rates of individual FO and MD processes. It was found that the integrated system is stable and sustainable when the water transfer rate of FO subsystem is equal to that of MD subsystem. The rejections to main contaminants in human urine were also investigated. Although individual FO process had relatively high rejection to Total Organic Carbon (TOC), Total Nitrogen (TN) and Ammonium Nitrogen (NH4(+)-N) in human urine, these contaminants could also accumulate in draw solution after long term performance. The MD process provided an effective rejection to contaminants in draw solution after FO process and the integrated system revealed nearly complete rejection to TOC, TN and NH4(+)-N. This work provided a potential treatment process for human urine in some fields such as water regeneration in space station and water or nutrient recovery from source-separated urine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Material gap membrane distillation: A new design for water vapor flux enhancement

    KAUST Repository

    Francis, Lijo

    2013-08-19

    A new module design for membrane distillation, namely material gap membrane distillation (MGMD), for seawater desalination has been proposed and successfully tested. It has been observed that employing appropriate materials between the membrane and the condensation plate in an air gap membrane distillation (AGMD) module enhanced the water vapor flux significantly. An increase in the water vapor flux of about 200-800% was observed by filling the gap with sand and DI water at various feed water temperatures. However, insulating materials such as polypropylene and polyurethane have no effect on the water vapor flux. The influence of material thickness and characteristics has also been investigated in this study. An increase in the water gap width from 9. mm to 13. mm increases the water vapor flux. An investigation on an AGMD and MGMD performance comparison, carried out using two different commercial membranes provided by different manufacturers, is also reported in this paper. © 2013 Elsevier B.V.

  9. Contact structure for use in catalytic distillation

    Science.gov (United States)

    Jones, E.M. Jr.

    1984-03-27

    A method is described for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor, contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

  10. Recovery of volatile aroma compounds from black currant juice by vacuum membrane distillation

    DEFF Research Database (Denmark)

    Bagger-Jørgensen, Rico; Meyer, Anne S.; Warming, C.

    2004-01-01

    This study evaluated the recovery of seven characteristic black currant aroma compounds by vacuum membrane distillation (VMD) carried out at low temperatures (10-45 degreesC) and at varying feed flow rates (100-500 l/h) in a lab scale membrane distillation set tip. VMD at feed flow from 100 to 500...

  11. Optimal design and control of solar driven air gap membrane distillation desalination systems

    International Nuclear Information System (INIS)

    Chen, Yih-Hang; Li, Yu-Wei; Chang, Hsuan

    2012-01-01

    Highlights: ► Air gap membrane distillation unit was used in the desalination plants. ► Aspen Custom Molder was used to simulate each unit of desalination plants. ► Design parameters were investigated to obtain the minimum total annual cost. ► The control structure was proposed to operate desalination plants all day long. -- Abstract: A solar heated membrane distillation desalination system is constructed of solar collectors and membrane distillation devices for increasing pure water productivity. This technically and economically feasible system is designed to use indirect solar heat to drive membrane distillation processes to overcome the unstable supply of solar radiation from sunrise to sunset. The solar heated membrane distillation desalination system in the present study consisted of hot water storage devices, heat exchangers, air gap membrane distillation units, and solar collectors. Aspen Custom Molder (ACM) software was used to model and simulate each unit and establish the cost function of a desalination plant. From Design degree of freedom (DOF) analysis, ten design parameters were investigated to obtain the minimum total annual cost (TAC) with fixed pure water production rate. For a given solar energy density profile of typical summer weather, the minimal TAC per 1 m 3 pure water production can be found at 500 W/m 2 by varying the solar energy intensity. Therefore, we proposed two modes for controlling the optimal design condition of the desalination plant; day and night. In order to widen the operability range of the plant, the sensitivity analysis was used to retrofit the original design point to lower the effluent temperature from the solar collector by increasing the hot water recycled stream. The simulation results show that the pure water production can be maintained at a very stable level whether in sunny or cloudy weather.

  12. Membrane distillation with porous metal hollow fibers for the concentration of thermo-sensitive solutions

    NARCIS (Netherlands)

    Shukla, Sushumna

    2014-01-01

    This thesis presents an original approach for the concentration of thermo-sensitive solutions: the Sweep Gas Membrane Distillation (SGMD) process. A new membrane contactor with metallic hollow fibers has been designed and allows the distillation process to be operational at low temperature. Heat is

  13. Optimization Study of Small-Scale Solar Membrane Distillation Desalination Systems (s-SMDDS

    Directory of Open Access Journals (Sweden)

    Hsuan Chang

    2014-11-01

    Full Text Available Membrane distillation (MD, which can utilize low-grade thermal energy, has been extensively studied for desalination. By incorporating solar thermal energy, the solar membrane distillation desalination system (SMDDS is a potential technology for resolving energy and water resource problems. Small-scale SMDDS (s-SMDDS is an attractive and viable option for the production of fresh water for small communities in remote arid areas. The minimum cost design and operation of s-SMDDS are determined by a systematic method, which involves a pseudo-steady-state approach for equipment sizing and dynamic optimization using overall system mathematical models. Two s-SMDDS employing an air gap membrane distillation module with membrane areas of 11.5 m2 and 23 m2 are analyzed. The lowest water production costs are $5.92/m3 and $5.16/m3 for water production rates of 500 kg/day and 1000 kg/day, respectively. For these two optimal cases, the performance ratios are 0.85 and 0.91; the recovery ratios are 4.07% and 4.57%. The effect of membrane characteristics on the production cost is investigated. For the commercial membrane employed in this study, the increase of the membrane mass transfer coefficient up to two times is beneficial for cost reduction.

  14. Arsenic removal by solar-driven membrane distillation: modeling and experimental investigation with a new flash vaporization module.

    Science.gov (United States)

    Pa, Parimal; Manna, Ajay Kumar; Linnanen, Lassi

    2013-01-01

    A modeling and simulation study was carried out on a new flux-enhancing and solar-driven membrane distillation module for removal of arsenic from contaminated groundwater. The developed new model was validated with rigorous experimental investigations using arsenic-contaminated groundwater. By incorporating flash vaporization dynamics, the model turned out to be substantially different from the existing direct contact membrane distillation models and could successfully predict (with relative error of only 0.042 and a Willmott d-index of 0.997) the performance of such an arsenic removal unit where the existing models exhibited wide variation with experimental findings in the new design. The module with greater than 99% arsenic removal efficiency and greater than 50 L/m2 x h flux could be implemented in arsenic-affected villages in Southeast Asian countries with abundant solar energy, and thus could give relief to millions of affected people. These encouraging results will raise scale-up confidence.

  15. Nanophotonics-enabled solar membrane distillation for off-grid water purification.

    Science.gov (United States)

    Dongare, Pratiksha D; Alabastri, Alessandro; Pedersen, Seth; Zodrow, Katherine R; Hogan, Nathaniel J; Neumann, Oara; Wu, Jinjian; Wang, Tianxiao; Deshmukh, Akshay; Elimelech, Menachem; Li, Qilin; Nordlander, Peter; Halas, Naomi J

    2017-07-03

    With more than a billion people lacking accessible drinking water, there is a critical need to convert nonpotable sources such as seawater to water suitable for human use. However, energy requirements of desalination plants account for half their operating costs, so alternative, lower energy approaches are equally critical. Membrane distillation (MD) has shown potential due to its low operating temperature and pressure requirements, but the requirement of heating the input water makes it energy intensive. Here, we demonstrate nanophotonics-enabled solar membrane distillation (NESMD), where highly localized photothermal heating induced by solar illumination alone drives the distillation process, entirely eliminating the requirement of heating the input water. Unlike MD, NESMD can be scaled to larger systems and shows increased efficiencies with decreased input flow velocities. Along with its increased efficiency at higher ambient temperatures, these properties all point to NESMD as a promising solution for household- or community-scale desalination.

  16. Fabrication of electrospun nanofibrous membranes for membrane distillation application

    KAUST Repository

    Francis, Lijo; Maab, Husnul; Alsaadi, Ahmad Salem; Nunes, Suzana Pereira; Ghaffour, NorEddine; Amy, Gary L.

    2013-01-01

    Nanofibrous membranes of Matrimid have been successfully fabricated using an electrospinning technique under optimized conditions. Nanofibrous membranes are found to be highly hydrophobic with a high water contact angle of 130°. Field emission

  17. Development of highly porous flat sheet polyvinylidene fluoride (PVDF) membranes for membrane distillation

    KAUST Repository

    Alsaery, Salim A.

    2017-05-01

    With the increase of population every year, fresh water scarcity has rapidly increased and it is reaching a risky level, particularly in Africa and the Middle East. Desalination of seawater is an essential process for fresh water generation. One of the methods for desalination is membrane distillation (MD). MD process separates an aqueous liquid feed across a porous hydrophobic membrane to produce pure water via evaporation. Polyvinlidene fluoride (PVDF) membranes reinforced with a polyester fabric were fabricated as potential candidates for MD. Non-solvent induced phase separation coupled with steam treatment was used to prepare the PVDF membranes. A portion of the prepared membrane was coated with Teflon (AF2400) to increase its hydrophobicity. In the first study, the fabricated membranes were characterized using scanning electron microscopy and other techniques, and they were evaluated using direct contact MD (DCMD). The fabricated membranes showed a porous sponge-like structure with some macrovoids. The macrovoid formation and the spongy structure in the membrane cross-sections contributed significantly to a high permeate flux as they provide a large space for vapor water transport. The modified PVDF membranes with steaming and coating exhibited a permeate flux of around 40 L/h m2 (i.e. 27-30% increase to the control PVDF membrane) at temperatures of 60 °C (feed) and 20 °C (permeate). This increase in the permeate flux for the modified membranes was mainly attributed to its larger pore size on the bottom surface. In the second study, the control PVDF membrane was tested in two different module designs (i.e. semi-circular pipe and rectangular duct module designs). The semi-circular module design (turbulent regime) exhibited a higher permeate flux, 3-fold higher than that of the rectangular duct module design (laminar regime) at feed temperature of 60 °C. Furthermore, a heat energy balance was performed for each module design to determine the temperature

  18. Design of Microporosity in Membrane Distillation

    Science.gov (United States)

    Zhao, Tom; Patankar, Neelesh

    2017-11-01

    Membrane Distillation (MD) is a desalination method where only vapor can pass through pores in a hydrophobic membrane. Unlike reverse osmosis, MD is insensitive to feed salinity (osmotic pressure) and demonstrates near 100% salt rejection in processing wastewater with a high concentration of nonvolatile impurities. To maximize vapor flux and maintain salt rejection, we demonstrate using molecular dynamics the critical pore radius below which the liquid feed will not intrude or nucleate inside the pores for cylindrical, re-entrant and conical pore geometries. We note that re-entrant structures not only can process low surface-tension wastewater due to its inherent oleophobicity, but can also be optimized to achieve maximum vapor transport compared to all other pore geometries as a function of the material hydrophobicity.

  19. Aroma Stripping under various Forms of Membrane Distillation Processes: Experiments and modeling

    DEFF Research Database (Denmark)

    Jonsson, Gunnar Eigil

    the large different in permeate flux and concentration factor that was observed for the different MD configurations. This is highly related to the heat and mass transfer resistances in the membrane as well as in the boundary layers adjacent to the membrane surface and how the driving force develops along......Concentration of fruit juices by membrane distillation is an interesting process as it can be done at low temperature giving a gentle concentration process with little deterioration of the juices. Since the juices contains many different aroma compounds with a wide range of chemical properties...... such as volatility, activity coefficient and vapor pressure, it is important to know how these aroma compounds will eventually pass through the membrane. Experiments have been made on an aroma model solution and on black currant juice in a lab scale membrane distillation set up which can be operated in various types...

  20. Integrated membrane distillation-crystallization: process design and cost estimations for seawater treatment and fluxes of single salt solutions

    NARCIS (Netherlands)

    Creusen, R.J.M.; Medevoort, J. van; Roelands, C.P.M.; Renesse van Duivenbode, J.A.D. van; Hanemaaijer, J.H.; Leerdam, R.C. van

    2013-01-01

    The goal of this research is to design an integrated membrane distillation-crystallization (MDC) process for desalination of seawater with pure water and dry salts as the only products. The process is based on a combination of membrane distillation (MD) and osmotic distillation (OD) steps with

  1. Effectiveness of Water Desalination by Membrane Distillation Process

    Directory of Open Access Journals (Sweden)

    Marek Gryta

    2012-07-01

    Full Text Available The membrane distillation process constitutes one of the possibilities for a new method for water desalination. Four kinds of polypropylene membranes with different diameters of capillaries and pores, as well as wall thicknesses were used in studied. The morphology of the membrane used and the operating parameters significantly influenced process efficiency. It was found that the membranes with lower wall thickness and a larger pore size resulted in the higher yields. Increasing both feed flow rate and temperature increases the permeate flux and simultaneously the process efficiency. However, the use of higher flow rates also enhanced heat losses by conduction, which decreases the thermal efficiency. This efficiency also decreases when the salt concentration in the feed was enhanced. The influence of fouling on the process efficiency was considered.

  2. Water recycling and desalination by air gap membrane distillation

    NARCIS (Netherlands)

    Meindersma, G.W.; Guijt, C.M.; de Haan, A.B.

    2005-01-01

    Because salt and other small components are the most common compounds in wastewater from the process industry, desalination techniques are likely to be suitable as treatment processes in many cases. Although membrane distillation (MD) is a well-known technology for desalination and water treatment,

  3. Exploring the potential of commercial polyethylene membranes for desalination by membrane distillation

    KAUST Repository

    Zuo, Jian; Bonyadi, Sina; Chung, Neal Tai-Shung

    2015-01-01

    The potential of utilizing polyethylene (PE) membranes in membrane distillation (MD) for sea water desalination has been explored in this study. The advantages of using PE membranes are (1) their intrinsic hydrophobicity with low surface energy of 28-33×10N/m, (2) good chemical stability and low thermal conductivity and (3) their commercial availability that may expedite the MD commercialization process. Several commercial PE membranes with different physicochemical properties are employed to study the capability and feasibility of PE membrane application in an MD process. The effect of membrane pore size, porosity, thickness and wetting resistance on MD performance and energy efficiency have been investigated. The PE membranes demonstrate impressive separation performance with permeation fluxes reaching 123.0L/mh for a 3.5wt% sodium chloride (NaCl) feed solution at 80°C. This superior performance surpasses most of the prior commercial and lab-made flat sheet and hollow fiber membranes. A long term MD testing of 100h is also performed to evaluate the durability of PE membranes, and a relatively stable performance is observed during the entire experiment. This long term stability signifies the suitability of PE membranes for MD applications.

  4. Exploring the potential of commercial polyethylene membranes for desalination by membrane distillation

    KAUST Repository

    Zuo, Jian

    2015-09-26

    The potential of utilizing polyethylene (PE) membranes in membrane distillation (MD) for sea water desalination has been explored in this study. The advantages of using PE membranes are (1) their intrinsic hydrophobicity with low surface energy of 28-33×10N/m, (2) good chemical stability and low thermal conductivity and (3) their commercial availability that may expedite the MD commercialization process. Several commercial PE membranes with different physicochemical properties are employed to study the capability and feasibility of PE membrane application in an MD process. The effect of membrane pore size, porosity, thickness and wetting resistance on MD performance and energy efficiency have been investigated. The PE membranes demonstrate impressive separation performance with permeation fluxes reaching 123.0L/mh for a 3.5wt% sodium chloride (NaCl) feed solution at 80°C. This superior performance surpasses most of the prior commercial and lab-made flat sheet and hollow fiber membranes. A long term MD testing of 100h is also performed to evaluate the durability of PE membranes, and a relatively stable performance is observed during the entire experiment. This long term stability signifies the suitability of PE membranes for MD applications.

  5. An advanced online monitoring approach to study the scaling behavior in direct contact membrane distillation

    KAUST Repository

    Lee, Jung Gil

    2017-10-12

    One of the major challenges in membrane distillation (MD) desalination is scaling, mainly CaSO4 and CaCO3. In this study, in order to achieve a better understanding and establish a strategy for controlling scaling, a detailed investigation on the MD scaling was performed by using various analytical methods, especially an in-situ monitoring technique using an optical coherence tomography (OCT) to observe the cross-sectional view on the membrane surface during operation. Different concentrations of CaSO4, CaCO3, as well as NaCl were tested separately and in different mixed feed solutions. Results showed that when CaSO4 alone was employed in the feed solution, the mean permeate flux (MPF) has significantly dropped at lower volume concentration factor (VCF) compared to other feed solutions and this critical point was observed to be influenced by the solubility changes of CaSO4 resulting from the various inlet feed temperatures. Although the inlet feed and permeate flow rates could contribute to the initial MPF value, the VCF, which showed a sharp MPF decline, was not affected. It was clearly observed that the scaling on the membrane surface due to crystal growth in the bulk and the deposition of aggregated crystals on the membrane surface abruptly appeared close to the critical point of VCF by using OCT observation in a real time. On the other hand, NaCl + CaSO4 mixed feed solution resulted in a linear MPF decline as VCF increases and delayed the critical point to higher VCF values. In addition, CaCO3 alone in feed solution did not affect the scaling, however, when CaSO4 was added to CaCO3, the initial MPF decline and VCF met the critical point earlier. In summary, calcium scaling crystal formed at different conditions influenced the filtration dynamics and MD performances.

  6. Membrane Contact Sites: Complex Zones for Membrane Association and Lipid Exchange

    Science.gov (United States)

    Quon, Evan; Beh, Christopher T.

    2015-01-01

    Lipid transport between membranes within cells involves vesicle and protein carriers, but as agents of nonvesicular lipid transfer, the role of membrane contact sites has received increasing attention. As zones for lipid metabolism and exchange, various membrane contact sites mediate direct associations between different organelles. In particular, membrane contact sites linking the plasma membrane (PM) and the endoplasmic reticulum (ER) represent important regulators of lipid and ion transfer. In yeast, cortical ER is stapled to the PM through membrane-tethering proteins, which establish a direct connection between the membranes. In this review, we consider passive and facilitated models for lipid transfer at PM–ER contact sites. Besides the tethering proteins, we examine the roles of an additional repertoire of lipid and protein regulators that prime and propagate PM–ER membrane association. We conclude that instead of being simple mediators of membrane association, regulatory components of membrane contact sites have complex and multilayered functions. PMID:26949334

  7. Theoretical modeling and experimental validation of transport and separation properties of carbon nanotube electrospun membrane distillation

    KAUST Repository

    Lee, Jung Gil; Lee, Eui-Jong; Jeong, Sanghyun; Guo, Jiaxin; An, Alicia Kyoungjin; Guo, Hong; Kim, Joonha; Leiknes, TorOve; Ghaffour, NorEddine

    2016-01-01

    Developing a high flux and selective membrane is required to make membrane distillation (MD) a more attractive desalination process. Amongst other characteristics membrane hydrophobicity is significantly important to get high vapor transport and low wettability. In this study, a laboratory fabricated carbon nanotubes (CNTs) composite electrospun (E-CNT) membrane was tested and has showed a higher permeate flux compared to poly(vinylidene fluoride-co-hexafluoropropylene) (PH) electrospun membrane (E-PH membrane) in a direct contact MD (DCMD) configuration. Only 1% and 2% of CNTs incorporation resulted in an enhanced permeate flux with lower sensitivity to feed salinity while treating a 35 and 70 g/L NaCl solutions. Experimental results and the mechanisms of E-CNT membrane were validated by a proposed new step-modeling approach. The increased vapor transport in E-CNT membranes could not be elucidated by an enhancement of mass transfer only at a given physico-chemical properties. However, the theoretical modeling approach considering the heat and mass transfers simultaneously enabled to explain successfully the enhanced flux in the DCMD process using E-CNT membranes. This indicates that both mass and heat transfers improved by CNTs are attributed to the enhanced vapor transport in the E-CNT membrane.

  8. Theoretical modeling and experimental validation of transport and separation properties of carbon nanotube electrospun membrane distillation

    KAUST Repository

    Lee, Jung Gil

    2016-12-27

    Developing a high flux and selective membrane is required to make membrane distillation (MD) a more attractive desalination process. Amongst other characteristics membrane hydrophobicity is significantly important to get high vapor transport and low wettability. In this study, a laboratory fabricated carbon nanotubes (CNTs) composite electrospun (E-CNT) membrane was tested and has showed a higher permeate flux compared to poly(vinylidene fluoride-co-hexafluoropropylene) (PH) electrospun membrane (E-PH membrane) in a direct contact MD (DCMD) configuration. Only 1% and 2% of CNTs incorporation resulted in an enhanced permeate flux with lower sensitivity to feed salinity while treating a 35 and 70 g/L NaCl solutions. Experimental results and the mechanisms of E-CNT membrane were validated by a proposed new step-modeling approach. The increased vapor transport in E-CNT membranes could not be elucidated by an enhancement of mass transfer only at a given physico-chemical properties. However, the theoretical modeling approach considering the heat and mass transfers simultaneously enabled to explain successfully the enhanced flux in the DCMD process using E-CNT membranes. This indicates that both mass and heat transfers improved by CNTs are attributed to the enhanced vapor transport in the E-CNT membrane.

  9. Enhanced Freshwater Production Using Finned-Plate Air Gap Membrane Distillation (AGMD

    Directory of Open Access Journals (Sweden)

    Perves Bappy Mohammad Jabed

    2017-01-01

    Full Text Available Air Gap membrane distillation (AGMD, a special type of energy efficient membrane distillation process, is a technology for producing freshwater from waste water. Having some benefits over other traditional processes, this method has been able to draw attention of researchers working in the field of freshwater production technologies. In this study, a basic AGMD system with flat coolant plate has been modified using a specially designed channelled coolant plate of portable size to observe its effect over the production rate and performance of the system. Attempt has been made to increase the amount of distillate flux by using the “fin effect” of the channelled coolant plate. A finned plate have been used instead of a flat coolant plate and experiments were conducted to compare the effect. Coolant temperature and feed temperature of the system have been varied from 10°C to 25°C and 40°C to 70°C respectively. Comparing the data, around 50% to 58% distillate enhancement has been observed for channelled coolant plate. Also, it was seen that the enhancement was higher for higher feed temperatures and coolant temperatures. With these findings, a better performing AGMD module has been introduced to mitigate the scarcity of freshwater.

  10. Batch pervaporative fermentation with coupled membrane and its influence on energy consumption in permeate recovery and distillation stage

    International Nuclear Information System (INIS)

    Leon, Juan A.; Palacios-Bereche, Reynaldo; Nebra, Silvia A.

    2016-01-01

    In the ethanol production process from sugarcane molasses, the distillation process is a high-energy demand stage. The distillation energy efficiency is strongly associated with the alcoholic fermentation performance in the process. The final ethanol concentration in the alcoholic wines has a direct impact on consumption of thermal energy in ethanol separation. In this paper, ethanol production with a H-SBMF (Hybrid-Simple Batch Membrane Fermenter) using PDMS (polydimethylsiloxane) pervaporation membrane was modelled and simulated, in order to determine its influence on energy consumption in distillation. Steam in distillation and electrical energy needs in permeate recovery were mainly influenced by membrane adaptation. The H-SBMF achieved a higher ethanol production in the range of 10–13% compared to the conventional batch fermenter, and an increase in productivity of 150%. The distillation system consisted of two sets of columns: the ethanol recovery column and the rectification column. The permeate recovery system (i.e. vacuum and compression) was regarded in order to evaluate the electrical energy requirement, and the thermal energy demand was evaluated. A decrease in steam consumption was evidenced by the adaptation of the membrane to the fermenter. Higher energy efficiencies were achieved in distillation with larger membrane areas, achieving almost 17% steam reduction. - Highlights: • Higher and faster ethanol productions were achieved by fermenter hybridization. • Multi-stage permeate compression and inter-stage heat recovery were assumed. • Energy demand was studied based on an integrated fermentation and distillation scheme. • High-energy efficiency was attained in the distillation to produce hydrated alcohol.

  11. Membrane Contact Sites: Complex Zones for Membrane Association and Lipid Exchange

    OpenAIRE

    Evan Quon; Christopher T. Beh

    2016-01-01

    Lipid transport between membranes within cells involves vesicle and protein carriers, but as agents of nonvesicular lipid transfer, the role of membrane contact sites has received increasing attention. As zones for lipid metabolism and exchange, various membrane contact sites mediate direct associations between different organelles. In particular, membrane contact sites linking the plasma membrane (PM) and the endoplasmic reticulum (ER) represent important regulators of lipid and ion transfer...

  12. Seawater desalination with solar-energy-integrated vacuum membrane distillation system

    Directory of Open Access Journals (Sweden)

    Fang Wang

    2017-03-01

    Full Text Available This study designed and tested a novel type of solar-energy-integrated vacuum membrane distillation (VMD system for seawater desalination under actual environmental conditions in Wuhan, China. The system consists of eight parts: a seawater tank, solar collector, solar cooker, inclined VMD evaporator, circulating water vacuum pump, heat exchanger, fresh water tank, and brine tank. Natural seawater was used as feed and a hydrophobic hollow-fiber membrane module was used to improve seawater desalination. The experiment was conducted during a typical summer day. Results showed that when the highest ambient temperature was 33 °C, the maximum value of the average solar intensity was 1,080 W/m2. The system was able to generate 36 kg (per m2 membrane module distilled fresh water during 1 day (7:00 am until 6:00 pm, the retention rate was between 99.67 and 99.987%, and electrical conductivity was between 0.00276 and 0.0673 mS/cm. The average salt rejection was over 90%. The proposed VMD system shows favorable potential application in desalination of brackish waters or high-salt wastewater treatment, as well.

  13. Air gap membrane distillation. 2. Model validation and hollow fibre module performance analysis

    NARCIS (Netherlands)

    Guijt, C.M.; Meindersma, G.W.; Reith, T.; de Haan, A.B.

    2005-01-01

    In this paper the experimental results of counter current flow air gap membrane distillation experiments are presented and compared with predictive model calculations. Measurements were carried out with a cylindrical test module containing a single hollow fibre membrane in the centre and a

  14. High flux and antifouling properties of negatively charged membrane for dyeing wastewater treatment by membrane distillation

    KAUST Repository

    An, Alicia Kyoungjin; Guo, Jiaxin; Jeong, Sanghyun; Lee, Eui-Jong; Tabatabai, S. Assiyeh Alizadeh; Leiknes, TorOve

    2016-01-01

    This study investigated the applicability of membrane distillation (MD) to treat dyeing wastewater discharged by the textile industry. Four different dyes containing methylene blue (MB), crystal violet (CV), acid red 18 (AR), and acid yellow 36 (AY

  15. Soft sensing of system parameters in membrane distillation

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-03-23

    Various examples of methods and systems are provided for soft sensing of system parameters in membrane distillation (MD). In one example, a system includes a MD module comprising a feed side and a permeate side separated by a membrane boundary layer; and processing circuitry configured to estimate feed solution temperatures and permeate solution temperatures of the MD module using monitored outlet temperatures of the feed side and the permeate side. In another example, a method includes monitoring outlet temperatures of a feed side and a permeate side of a MD module to determine a current feed outlet temperature and a current permeate outlet temperature; and determining a plurality of estimated temperature states of a membrane boundary layer separating the feed side and the permeate side of the MD module using the current feed outlet temperature and the current permeate outlet temperature.

  16. Efficient ethanol recovery from fermentation broths with integrated distillation-membrane process

    Science.gov (United States)

    The energy demand of distillation-molecular sieve systems for ethanol recovery/dehydration can be significant, particularly for dilute solutions. An alternative process integrating vapor stripping (like a beer still) with vapor compression and a vapor permeation membrane separati...

  17. Morphology-properties relationship of gas plasma treated hydrophobic meso-porous membranes and their improved performance for desalination by membrane distillation

    International Nuclear Information System (INIS)

    Dumée, Ludovic F.; Alglave, Hortense; Chaffraix, Thomas; Lin, Bao; Magniez, Kevin; Schütz, Jürg

    2016-01-01

    Graphical abstract: - Highlights: • Systematic surface modifications by gas plasma treatment of hydrophobic polymers. • Correlation between plasma parameters and materials surface energy and morphology. • Spectral analysis of the formation of functional groups across the membranes surface. • Relationship between wettability, roughness and performance. - Abstract: The impact on performance of the surface energy and roughness of membrane materials used for direct contact membrane distillation are critical but yet poorly investigated parameters. The capacity to alter the wettability of highly hydrophobic materials such as poly(tetra-fluoro-ethylene) (PTFE) by gas plasma treatments is reported in this paper. An equally important contribution from this investigation arises from illustrating how vaporized material from the treated sample participates after a short while in the composition of the plasma and fundamentally changes the result of surface chemistry processes. The water contact angle across the hydrophobic membranes is generally controlled by varying the plasma gas conditions, such as the plasma power, chamber pressure and irradiation duration. Changes to surface porosity and roughness of the bulk material as well as the surface chemistry, through specific and partial de-fluorination of the surface were detected and systematically studied by Fourier transform infra-red analysis and scanning electron microscopy. It was found that the rupture of fibrils, formed during membrane processing by thermal-stretching, led to the formation of a denser surface composed of nodules similar to these naturally acting as bridging points across the membrane material between fibrils. This structural change has a profound and impart a permanent effect on the permeation across the modified membranes, which was found to be enhanced by up to 10% for long plasma exposures while the selectivity of the membranes was found to remain unaffected by the treatment at a level higher

  18. Morphology-properties relationship of gas plasma treated hydrophobic meso-porous membranes and their improved performance for desalination by membrane distillation

    Energy Technology Data Exchange (ETDEWEB)

    Dumée, Ludovic F., E-mail: ludovic.dumee@deakin.edu.au [Deakin University, Geelong Victoria–Australia - Institute for Frontier Materials (Australia); Alglave, Hortense; Chaffraix, Thomas; Lin, Bao; Magniez, Kevin [Deakin University, Geelong Victoria–Australia - Institute for Frontier Materials (Australia); Schütz, Jürg [CSIRO, Manufacturing Flagship, 75 Pigdons Road, 3216 Waurn Ponds, Victoria (Australia)

    2016-02-15

    Graphical abstract: - Highlights: • Systematic surface modifications by gas plasma treatment of hydrophobic polymers. • Correlation between plasma parameters and materials surface energy and morphology. • Spectral analysis of the formation of functional groups across the membranes surface. • Relationship between wettability, roughness and performance. - Abstract: The impact on performance of the surface energy and roughness of membrane materials used for direct contact membrane distillation are critical but yet poorly investigated parameters. The capacity to alter the wettability of highly hydrophobic materials such as poly(tetra-fluoro-ethylene) (PTFE) by gas plasma treatments is reported in this paper. An equally important contribution from this investigation arises from illustrating how vaporized material from the treated sample participates after a short while in the composition of the plasma and fundamentally changes the result of surface chemistry processes. The water contact angle across the hydrophobic membranes is generally controlled by varying the plasma gas conditions, such as the plasma power, chamber pressure and irradiation duration. Changes to surface porosity and roughness of the bulk material as well as the surface chemistry, through specific and partial de-fluorination of the surface were detected and systematically studied by Fourier transform infra-red analysis and scanning electron microscopy. It was found that the rupture of fibrils, formed during membrane processing by thermal-stretching, led to the formation of a denser surface composed of nodules similar to these naturally acting as bridging points across the membrane material between fibrils. This structural change has a profound and impart a permanent effect on the permeation across the modified membranes, which was found to be enhanced by up to 10% for long plasma exposures while the selectivity of the membranes was found to remain unaffected by the treatment at a level higher

  19. The regeneration of a liquid desiccant using direct contact membrane distillation to unlock the potential of coastal desert agriculture

    KAUST Repository

    Cribbs, Kimberly

    2018-04-01

    In Gulf Cooperation Council (GCC) countries, a lack of freshwater, poor soil quality, and ambient temperatures unsuitable for cultivation for parts of the year hinders domestic agriculture. The result is a reliance on a fluctuating supply of imported fresh produce which may have high costs and compromised quality. There are agricultural technologies available such as hydroponics and controlled environment agriculture (CEA) that can allow GCC countries to overcome poor soil quality and ambient temperatures unsuitable for cultivation, respectively. Evaporative cooling is the most common form of cooling for CEA and requires a significant amount of water. In water-scarce regions, it is desirable for sea or brackish water to be used for evaporative cooling. Unfortunately, in many coastal desert regions, evaporative cooling does not provide enough cooling due to the high wet-bulb temperature of the ambient air during hot and humid months of the year. A liquid desiccant dehumidification system has been proven to lower the wet-bulb temperature of ambient air in the coastal city of Jeddah, Saudi Arabia to a level that allows for evaporative cooling to meet the needs of heat-sensitive crops. Much of the past research on the regeneration of the liquid desiccant solution has been on configurations that release water vapor back to the atmosphere. Studies have shown that the amount of water captured by the liquid desiccant when used to dehumidify a greenhouse can supply a significant amount of the water needed for irrigation. This thesis studied the regeneration of a magnesium chloride (MgCl2) liquid desiccant solution from approximately 20 to 31wt% by direct contact membrane distillation and explored the possibility of using the recovered water for irrigation. Two microporous hydrophobic PTFE membranes were experimentally tested and modeled when the bulk feed and coolant temperature difference was between 10 and 60°C. In eight experiments, the salt rejection was higher than 99

  20. Novel thermal efficiency-based model for determination of thermal conductivity of membrane distillation membranes

    International Nuclear Information System (INIS)

    Vanneste, Johan; Bush, John A.; Hickenbottom, Kerri L.; Marks, Christopher A.; Jassby, David

    2017-01-01

    Development and selection of membranes for membrane distillation (MD) could be accelerated if all performance-determining characteristics of the membrane could be obtained during MD operation without the need to recur to specialized or cumbersome porosity or thermal conductivity measurement techniques. By redefining the thermal efficiency, the Schofield method could be adapted to describe the flux without prior knowledge of membrane porosity, thickness, or thermal conductivity. A total of 17 commercially available membranes were analyzed in terms of flux and thermal efficiency to assess their suitability for application in MD. The thermal-efficiency based model described the flux with an average %RMSE of 4.5%, which was in the same range as the standard deviation on the measured flux. The redefinition of the thermal efficiency also enabled MD to be used as a novel thermal conductivity measurement device for thin porous hydrophobic films that cannot be measured with the conventional laser flash diffusivity technique.

  1. Application of vacuum membrane distillation to lithium bromide absorption refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zanshe; Feng, Shiyu; Li, Yun [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Gu, Zhaolin [School of Human Settlement and Civil Engineering, Xi' an Jiaotong University, Xi' an 710049 (China)

    2009-11-15

    Conventional generator in lithium bromide absorption refrigeration system is too bulky and heavy to be fitted into small scale device, and the temperature of the driving heater in the generator seems much higher than low grade energy such as regenerative energy or waste heat energy. In this paper, desorption of aqueous lithium bromide solution by vacuum membrane distillation process was presented. Hollow fiber membrane module made by polyvinylidene fluoride was used as desorption device of aqueous lithium bromide solution. Influencing factors of feed flux, feed temperature in lumen side and vacuum pressure in shell side were tested and analyzed with orthogonal test. The results showed that permeation flux of water vapor increased with the feed temperature increasing and the feed flux increasing in lumen side, and the permeation flux also went up along with absolute pressure drop in shell side. Feasibility and potential application analysis shows that the temperature of the driving heat was low and the volume and weight of the desorption device was light. In this study, vacuum membrane distillation to the lithium bromide absorption refrigeration system has proved to be an efficient and cheap desorption mode. (author)

  2. An anaerobic membrane bioreactor - membrane distillation hybrid system for energy recovery and water reuse: Removal performance of organic carbon, nutrients, and trace organic contaminants.

    Science.gov (United States)

    Song, Xiaoye; Luo, Wenhai; McDonald, James; Khan, Stuart J; Hai, Faisal I; Price, William E; Nghiem, Long D

    2018-07-01

    In this study, a direct contact membrane distillation (MD) unit was integrated with an anaerobic membrane bioreactor (AnMBR) to simultaneously recover energy and produce high quality water for reuse from wastewater. Results show that AnMBR could produce 0.3-0.5L/g COD added biogas with a stable methane content of approximately 65%. By integrating MD with AnMBR, bulk organic matter and phosphate were almost completely removed. The removal of the 26 selected trace organic contaminants by AnMBR was compound specific, but the MD process could complement AnMBR removal, leading to an overall efficiency from 76% to complete removal by the integrated system. The results also show that, due to complete retention, organic matter (such as humic-like and protein-like substances) and inorganic salts accumulated in the MD feed solution and therefore resulted in significant fouling of the MD unit. As a result, the water flux of the MD process decreased continuously. Nevertheless, membrane pore wetting was not observed throughout the operation. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  3. In-situcross-linked PVDF membranes with enhanced mechanical durability for vacuum membrane distillation

    KAUST Repository

    Zuo, Jian; Chung, Neal Tai-Shung

    2016-01-01

    A novel and effective one-step method has been demonstrated to fabricate cross-linked polyvinylidene fluoride (PVDF) membranes with better mechanical properties and flux for seawater desalination via vacuum membrane distillation (VMD). This method involves the addition of two functional nonsolvent additives; namely, water and ethylenediamine (EDA), into the polymer casting solution. The former acts as a pore forming agent, while the latter performs as a cross-linking inducer. The incorporation of water tends to increase membrane flux via increasing porosity and pore size but sacrifices membrane mechanical properties. Conversely, the presence of EDA enhances membrane mechanical properties through in-situ cross-linking reaction. Therefore, by synergistically combining the effects of both functional additives, the resultant PVDF membranes have shown good MD performance and mechanical properties simultaneously. The parameters that affect the cross-link reaction and membrane mechanical properties such as reaction duration and EDA concentration have been systematically studied. The membranes cast from an optimal reaction condition comprising 0.8 wt % EDA and 3-hour reaction not only shows a 40% enhancement in membrane Young's Modulus compared to the one without EDA but also achieves a good VMD flux of 43.6 L/m2-h at 60°C. This study may open up a totally new approach to design next-generation high performance MD membranes. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4013–4022, 2016

  4. In-situcross-linked PVDF membranes with enhanced mechanical durability for vacuum membrane distillation

    KAUST Repository

    Zuo, Jian

    2016-05-12

    A novel and effective one-step method has been demonstrated to fabricate cross-linked polyvinylidene fluoride (PVDF) membranes with better mechanical properties and flux for seawater desalination via vacuum membrane distillation (VMD). This method involves the addition of two functional nonsolvent additives; namely, water and ethylenediamine (EDA), into the polymer casting solution. The former acts as a pore forming agent, while the latter performs as a cross-linking inducer. The incorporation of water tends to increase membrane flux via increasing porosity and pore size but sacrifices membrane mechanical properties. Conversely, the presence of EDA enhances membrane mechanical properties through in-situ cross-linking reaction. Therefore, by synergistically combining the effects of both functional additives, the resultant PVDF membranes have shown good MD performance and mechanical properties simultaneously. The parameters that affect the cross-link reaction and membrane mechanical properties such as reaction duration and EDA concentration have been systematically studied. The membranes cast from an optimal reaction condition comprising 0.8 wt % EDA and 3-hour reaction not only shows a 40% enhancement in membrane Young\\'s Modulus compared to the one without EDA but also achieves a good VMD flux of 43.6 L/m2-h at 60°C. This study may open up a totally new approach to design next-generation high performance MD membranes. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4013–4022, 2016

  5. Modeling of air-gap membrane distillation process: A theoretical and experimental study

    KAUST Repository

    Alsaadi, Ahmad Salem; Ghaffour, NorEddine; Li, Junde; Gray, Stephen R.; Francis, Lijo; Maab, Husnul; Amy, Gary L.

    2013-01-01

    A one dimensional (1-D) air gap membrane distillation (AGMD) model for flat sheet type modules has been developed. This model is based on mathematical equations that describe the heat and mass transfer mechanisms of a single-stage AGMD process

  6. Fate and wetting potential of bio-refractory organics in membrane distillation for coke wastewater treatment.

    Science.gov (United States)

    Ren, Jing; Li, Jianfeng; Chen, Zuliang; Cheng, Fangqin

    2018-06-02

    Membrane distillation (MD) has been hindered in industrial applications due to the potential wetting or fouling caused by complicated organic compositions. This study investigated the correlations between the fate and wetting potential of bio-refractory organics in the MD process, where three coke wastewater samples pre-treated with bio-degradation and coagulation served as feed solutions. Results showed that although most of the bio-refractory organics in coke wastewater were rejected by the hydrophobic membrane, some volatile aromatic organics including benzenes, phenols, quinolines and naphthalenes passed through the membrane during the MD process. Interestingly, membrane wetting occurred coincidently with the penetration of phenolic and heterocyclic organics. The wetting rate was obviously correlated with the feed composition and membrane surface properties. Ultimately, novel insights into the anti-wetting strategy of MD with bio-refractory organics was proposed, illustrating that the polyaluminum chloride/polyacrylamide coagulation not only removed contaminants which could accelerate membrane wetting, but also retarded membrane wetting by the complexation with organics. The deposition of these complexes on the membrane surface introduced a secondary hydrophilic layer on the hydrophobic substrate, which established a composite membrane structure with superior wetting resistance. These new findings would be beneficial to wetting control in membrane distillation for wastewater treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Endoplasmic Reticulum-Plasma Membrane Contact Sites.

    Science.gov (United States)

    Saheki, Yasunori; De Camilli, Pietro

    2017-06-20

    The endoplasmic reticulum (ER) has a broad localization throughout the cell and forms direct physical contacts with all other classes of membranous organelles, including the plasma membrane (PM). A number of protein tethers that mediate these contacts have been identified, and study of these protein tethers has revealed a multiplicity of roles in cell physiology, including regulation of intracellular Ca 2+ dynamics and signaling as well as control of lipid traffic and homeostasis. In this review, we discuss the cross talk between the ER and the PM mediated by direct contacts. We review factors that tether the two membranes, their properties, and their dynamics in response to the functional state of the cell. We focus in particular on the role of ER-PM contacts in nonvesicular lipid transport between the two bilayers mediated by lipid transfer proteins.

  8. Autophagosomal membranes assemble at ER-plasma membrane contact sites.

    Science.gov (United States)

    Nascimbeni, Anna Chiara; Codogno, Patrice; Morel, Etienne

    2017-01-01

    The biogenesis of autophagosome, the double membrane bound organelle related to macro-autophagy, is a complex event requiring numerous key-proteins and membrane remodeling events. Our recent findings identify the extended synaptotagmins, crucial tethers of Endoplasmic Reticulum-plasma membrane contact sites, as key-regulators of this molecular sequence.

  9. A conceptual demonstration of freeze desalination-membrane distillation (FD-MD) hybrid desalination process utilizing liquefied natural gas (LNG) cold energy.

    Science.gov (United States)

    Wang, Peng; Chung, Tai-Shung

    2012-09-01

    The severe global water scarcity and record-high fossil oil price have greatly stimulated the research interests on new desalination technologies which can be driven by renewable energy or waste energy. In this study, a hybrid desalination process comprising freeze desalination and membrane distillation (FD-MD) processes was developed and explored in an attempt to utilize the waste cold energy released from re-gasification of liquefied natural gas (LNG). The concept of this technology was demonstrated using indirect-contact freeze desalination (ICFD) and direct-contact membrane distillation (DCMD) configurations. By optimizing the ICFD operation parameters, namely, the usage of nucleate seeds, operation duration and feed concentration, high quality drinkable water with a low salinity ∼0.144 g/L was produced in the ICFD process. At the same time, using the optimized hollow fiber module length and packing density in the DCMD process, ultra pure water with a low salinity of 0.062 g/L was attained at a condition of high energy efficiency (EE). Overall, by combining FD and MD processes and adopting the optimized operation parameters, the hybrid FD-MD system has been successfully demonstrated. A high total water recovery of 71.5% was achieved, and the water quality obtained met the standard for drinkable water. In addition, with results from specific energy calculation, it was proven that the hybrid process is an energy-saving process and utilization of LNG cold energy could greatly reduce the total energy consumption. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. The Effect of Non-condensable Gases Removal on Air Gap Membrane Distillation: Experimental and Simulation Studies

    KAUST Repository

    Alsaadi, Ahmad S.

    2014-04-01

    In the kingdom of Saudi Arabia (KSA), the current seawater desalination technologies are completely relying on burning unsustainable crude oil as their main energy driver. Saudi authorities have realized that the KSA is not going to be protected from the future global energy crisis and have started to set up a plan to diversify its energy resources. Membrane Distillation (MD) has emerged as an attractive alternative desalination process. It combines advantages from both thermal and membrane-based technologies and holds the potential of being a cost-effective separation process that can utilize low-grade waste heat or renewable energy. MD has four different configurations; among them is Air Gap Membrane Distillation (AGMD) which is the second most commonly tested and the most commercially available pilot-plant design. AGMD has a stagnant thin layer of air between the membrane and the condensation surface. This layer introduces a mass transfer resistance that makes the process require a large membrane surface area if a large quantity of fresh water is desired. This dissertation reports on experimental and theoretical work conducted to enhance the AGMD flux by removing non-condensable gases from the module and replacing it with either vacuum, liquid water or porous materials. At first, a mathematical model for AGMD was developed and validated experimentally to create a baseline for improvements that could be achieved after the removal of non-condensable gases. The mathematical model was then modified to simulate the process under vacuum where it showed a flux enhancement that reached 286%. The Water Gap Membrane Distillation (WGMD) configuration improved the flux by almost the same percentage. Since enhancing the flux is expected to increase temperature polarization effects, a theoretical study was conducted on the effect of temperature polarization in a Vacuum Membrane Distillation (VMD) configuration. The study showed that the effect of temperature polarization at

  11. Fouling mitigation in membrane distillation processes during ammonia stripping from pig manure

    DEFF Research Database (Denmark)

    Zarebska, Agata; Amor, Angel Cid; Ciurkot, Klaudia

    2015-01-01

    Over time fouling leads to membrane wetting. This is the biggest obstacle to widespread use of membrane distillation (MD) for ammonia removal from animal slurry. Feed pretreatment and cleaning strategies of membrane surfaces are the most common methods to prevent or diminish fouling phenomena....... This study investigates preliminary fouling of polypropylene (PP) and polytetrafluoroethylene (PTFE) membranes. A model manure solution was used as feed. In addition cleaning efficiencies with deionized water, NaOH/citric acid, and Novadan agents were studied. Further microfiltration and ultrafiltration were...... examined as manure pretreatment to diminish fouling. To this end polyvinylidene fluoride membranes (PVDF 0.2 µm and 150 kDa respectively) were used. Organic fouling was shown to be dominant. For the model manure solution the fouling comprised lipids, carbohydrates and proteins. For pig slurry the fouling...

  12. Large deformation contact mechanics of a pressurized long rectangular membrane. II. Adhesive contact

    Science.gov (United States)

    Srivastava, Abhishek; Hui, Chung-Yuen

    2013-01-01

    In part I of this work, we presented a theory for adhesionless contact of a pressurized neo-Hookean plane-strain membrane to a rigid substrate. Here, we extend our theory to include adhesion using a fracture mechanics approach. This theory is used to study contact hysteresis commonly observed in experiments. Detailed analysis is carried out to highlight the differences between frictionless and no-slip contact. Membrane detachment is found to be strongly dependent on adhesion: for low adhesion, the membrane ‘pinches-off’, whereas for large adhesions, it detaches unstably at finite contact (‘pull-off’). Expressions are derived for the critical adhesion needed for pinch-off to pull-off transition. Above a threshold adhesion, the membrane exhibits bistability, two stable states at zero applied pressure. The condition for bistability for both frictionless and no-slip boundary conditions is obtained explicitly. PMID:24353472

  13. Enhanced performance of PVDF nanocomposite membrane by nanofiber coating: A membrane for sustainable desalination through MD.

    Science.gov (United States)

    Efome, Johnson E; Rana, Dipak; Matsuura, Takeshi; Lan, Christopher Q

    2016-02-01

    Membrane distillation (MD) is a promising separation technique capable of being used in the desalination of marine and brackish water. Poly(vinylidene fluoride) (PVDF) flat sheet nano-composite membranes were surface modified by coating with electro-spun PVDF nano-fibres to increase the surface hydrophobicity. For this purpose, the nano-composite membrane containing 7 wt.% superhydrophobic SiO2 nano-particles, which showed the highest flux in our previous work, was first subjected to pore size augmentation by increasing the concentration of the pore forming agent (Di-ionized water). Then, the prepared flat sheet membranes were subjected to nanofibres coating by electro-spinning. The uncoated and coated composite fabricated membranes were characterized using contact angle, liquid entry pressure of water, and scanning electron microscopy. The membranes were further tested for 6 h desalination by direct contact membrane distillation (DCMD) and vacuum membrane distillation (VMD), with a 3.5 wt.% synthetic NaClaq as the feed. In DCMD the feed liquid and permeate side temperature were maintained at 27.5 °C and 15 °C, respectively. For VMD, the feed liquid temperature was 27 °C and a vacuum of 94.8 kPa was applied on the permeate side. The maximum permeate flux achieved was 3.2 kg/m(2).h for VMD and 6.5 kg/m(2).h for DCMD. The salt rejection obtained was higher than 99.98%. The coated membranes showed a more stable flux than the uncoated membranes indicating that the double layered membranes have great potential in solving the pore wetting problem in MD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. A theoretical study of a direct contact membrane distillation system coupled to a salt-gradient solar pond for terminal lakes reclamation.

    Science.gov (United States)

    Suárez, Francisco; Tyler, Scott W; Childress, Amy E

    2010-08-01

    Terminal lakes are water bodies that are located in closed watersheds with the only output of water occurring through evaporation or infiltration. The majority of these lakes, which are commonly located in the desert and influenced by human activities, are increasing in salinity. Treatment options are limited, due to energy costs, and many of these lakes provide an excellent opportunity to test solar-powered desalination systems. This paper theoretically investigates utilization of direct contact membrane distillation (DCMD) coupled to a salt-gradient solar pond (SGSP) for sustainable freshwater production at terminal lakes. A model for heat and mass transport in the DCMD module and a thermal model for an SGSP were developed and coupled to evaluate the feasibility of freshwater production. The construction of an SGSP outside and inside of a terminal lake was studied. As results showed that freshwater flows are on the same order of magnitude as evaporation, these systems will only be successful if the SGSP is constructed inside the terminal lake so that there is little or no net increase in surface area. For the study site of this investigation, water production on the order of 2.7 x 10(-3) m(3) d(-1) per m(2) of SGSP is possible. The major advantages of this system are that renewable thermal energy is used so that little electrical energy is required, the coupled system requires low maintenance, and the terminal lake provides a source of salts to create the stratification in the SGSP. (c) 2010 Elsevier Ltd. All rights reserved.

  15. Nonlinear Lyapunov-based boundary control of distributed heat transfer mechanisms in membrane distillation plant

    KAUST Repository

    Eleiwi, Fadi; Laleg-Kirati, Taous-Meriem

    2015-01-01

    This paper presents a nonlinear Lyapunov-based boundary control for the temperature difference of a membrane distillation boundary layers. The heat transfer mechanisms inside the process are modeled with a 2D advection-diffusion equation. The model

  16. Performance modeling of direct contact membrane distillation (DCMD) seawater desalination process using a commercial composite membrane

    KAUST Repository

    Lee, Junggil; Kim, Youngdeuk; Kim, Wooseung; Francis, Lijo; Amy, Gary L.; Ghaffour, NorEddine

    2015-01-01

    membrane and the heat transfer across the membrane and through the boundary layers adjacent to the membrane surfaces. Experimental results and model predictions for permeate flux and performance ratio are compared and shown to be in good agreement

  17. Evaluation of air gap membrane distillation process running under sub-atmospheric conditions: Experimental and simulation studies

    KAUST Repository

    Alsaadi, Ahmad S.; Francis, Lijo; Maab, Husnul; Amy, Gary L.; Ghaffour, NorEddine

    2015-01-01

    The importance of removing non-condensable gases from air gap membrane distillation (AGMD) modules in improving the water vapor flux is presented in this paper. Additionally, a previously developed AGMD mathematical model is used to predict to the degree of flux enhancement under sub-atmospheric pressure conditions. Since the mathematical model prediction is expected to be very sensitive to membrane distillation (MD) membrane resistance when the mass diffusion resistance is eliminated, the permeability of the membrane was carefully measured with two different methods (gas permeance test and vacuum MD permeability test). The mathematical model prediction was found to highly agree with the experimental data, which showed that the removal of non-condensable gases increased the flux by more than three-fold when the gap pressure was maintained at the saturation pressure of the feed temperature. The importance of staging the sub-atmospheric AGMD process and how this could give better control over the gap pressure as the feed temperature decreases are also highlighted in this paper. The effect of staging on the sub-atmospheric AGMD flux and its relation to membrane capital cost are briefly discussed.

  18. Evaluation of air gap membrane distillation process running under sub-atmospheric conditions: Experimental and simulation studies

    KAUST Repository

    Alsaadi, Ahmad S.

    2015-04-16

    The importance of removing non-condensable gases from air gap membrane distillation (AGMD) modules in improving the water vapor flux is presented in this paper. Additionally, a previously developed AGMD mathematical model is used to predict to the degree of flux enhancement under sub-atmospheric pressure conditions. Since the mathematical model prediction is expected to be very sensitive to membrane distillation (MD) membrane resistance when the mass diffusion resistance is eliminated, the permeability of the membrane was carefully measured with two different methods (gas permeance test and vacuum MD permeability test). The mathematical model prediction was found to highly agree with the experimental data, which showed that the removal of non-condensable gases increased the flux by more than three-fold when the gap pressure was maintained at the saturation pressure of the feed temperature. The importance of staging the sub-atmospheric AGMD process and how this could give better control over the gap pressure as the feed temperature decreases are also highlighted in this paper. The effect of staging on the sub-atmospheric AGMD flux and its relation to membrane capital cost are briefly discussed.

  19. Catalytic distillation process

    Science.gov (United States)

    Smith, L.A. Jr.

    1982-06-22

    A method is described for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C[sub 4] feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  20. Exergy Analysis of Air-Gap Membrane Distillation Systems for Water Purification Applications

    Directory of Open Access Journals (Sweden)

    Daniel Woldemariam

    2017-03-01

    Full Text Available Exergy analyses are essential tools for the performance evaluation of water desalination and other separation systems, including those featuring membrane distillation (MD. One of the challenges in the commercialization of MD technologies is its substantial heat demand, especially for large scale applications. Identifying such heat flows in the system plays a crucial role in pinpointing the heat loss and thermal integration potential by the help of exergy analysis. This study presents an exergetic evaluation of air-gap membrane distillation (AGMD systems at a laboratory and pilot scale. A series of experiments were conducted to obtain thermodynamic data for the water streams included in the calculations. Exergy efficiency and destruction for two different types of flat-plate AGMD were analyzed for a range of feed and coolant temperatures. The bench scale AGMD system incorporating condensation plate with more favorable heat conductivity contributed to improved performance parameters including permeate flux, specific heat demand, and exergy efficiency. For both types of AGMD systems, the contributions of the major components involved in exergy destruction were identified. The result suggested that the MD modules caused the highest fraction of destructions followed by re-concentrating tanks.

  1. Vacuumed gap membrane distillation (vagmed) module, multi-stage vagmed systems, and vagmed processes

    KAUST Repository

    Ghaffour, Noreddine

    2016-06-30

    Vacuumed gap membrane distillation (VAGMED) modules, and multi-stage VAGMED systems and processes using the modules are provided. In an embodiment, the membrane distillation modules (10) can comprise: a) a condenser (12) including a condensation surface (15); b) a first passageway (13) having an inlet for receiving a first feed stream (14) and an outlet through which the first stream can pass out of the first passageway, the first passageway configured to bring the first feed stream into thermal communication with the condensation surface; c) an evaporator (17) including a permeable evaporation surface allowing condensable gas to pass there through; d) a second passageway (18) having an inlet for receiving a second feed stream (19) and an outlet through which the second feed stream can pass out of the second passageway, the second passageway configured to bring the second feed stream into communication with the permeable evaporation surface; and e) an enclosure (24) providing a vacuum compartment within which the condenser, the evaporator and the first and second passageways of the module are contained.

  2. Vacuumed gap membrane distillation (vagmed) module, multi-stage vagmed systems, and vagmed processes

    KAUST Repository

    Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Francis, Lijo

    2016-01-01

    Vacuumed gap membrane distillation (VAGMED) modules, and multi-stage VAGMED systems and processes using the modules are provided. In an embodiment, the membrane distillation modules (10) can comprise: a) a condenser (12) including a condensation surface (15); b) a first passageway (13) having an inlet for receiving a first feed stream (14) and an outlet through which the first stream can pass out of the first passageway, the first passageway configured to bring the first feed stream into thermal communication with the condensation surface; c) an evaporator (17) including a permeable evaporation surface allowing condensable gas to pass there through; d) a second passageway (18) having an inlet for receiving a second feed stream (19) and an outlet through which the second feed stream can pass out of the second passageway, the second passageway configured to bring the second feed stream into communication with the permeable evaporation surface; and e) an enclosure (24) providing a vacuum compartment within which the condenser, the evaporator and the first and second passageways of the module are contained.

  3. Cyclic distillation technology - A mini-review

    DEFF Research Database (Denmark)

    Bîldea, Costin Sorin; Pătruţ, Cătălin; Jørgensen, Sten Bay

    2016-01-01

    Process intensification in distillation systems has received much attention during the pastdecades, with the aim of increasing both energy and separation efficiency. Varioustechniques, such as internal heat-integrated distillation, membrane distillation, rotating packedbed, dividing-wall columns...

  4. Performance Investigation of O-Ring Vacuum Membrane Distillation Module for Water Desalination

    Directory of Open Access Journals (Sweden)

    Adnan Alhathal Alanezi

    2016-01-01

    Full Text Available A new O-ring flat sheet membrane module design was used to investigate the performance of Vacuum Membrane Distillation (VMD for water desalination using two commercial polytetrafluoroethylene (PTFE and polyvinylidene fluoride (PVDF flat sheet hydrophobic membranes. The design of the membrane module proved its applicability for achieving a high heat transfer coefficient of the order of 103 (W/m2 K and a high Reynolds number (Re. VMD experiments were conducted to measure the heat and mass transfer coefficients within the membrane module. The effects of the process parameters, such as the feed temperature, feed flow rate, vacuum degree, and feed concentration, on the permeate flux have been investigated. The feed temperature, feed flow rate, and vacuum degree play an important role in enhancing the performance of the VMD process; therefore, optimizing all of these parameters is the best way to achieve a high permeate flux. The PTFE membrane showed better performance than the PVDF membrane in VMD desalination. The obtained water flux is relatively high compared to that reported in the literature, reaching 43.8 and 52.6 (kg/m2 h for PVDF and PTFE, respectively. The salt rejection of NaCl was higher than 99% for both membranes.

  5. Simultaneous production of high-quality water and electrical power from aqueous feedstock’s and waste heat by high-pressure membrane distillation

    NARCIS (Netherlands)

    Kuipers, N.J.M.; Hanemaaijer, J.H.; Brouwer, H.; Medevoort, J. van; Jansen, A.; Altena, F.; Vleuten, P. van der; Bak, H.

    2015-01-01

    A new membrane distillation (MD) concept (MemPower) has been developed for the simultaneous production of high-quality water from various aqueous feedstocks with cogeneration of mechanical power (electricity). Driven by low-grade heat (waste, solar, geothermal, etc.) a pressurized distillate can be

  6. Cyclic distillation technology - A mini-review

    NARCIS (Netherlands)

    Bîldea, Costin Sorin; Pătruţ, Cătălin; Jørgensen, Sten Bay; Abildskov, Jens; Kiss, Anton A.

    2016-01-01

    Process intensification in distillation systems has received much attention during past decades, with the aim of increasing both energy and separation efficiency. Various techniques, such as internal heat-integrated distillation, membrane distillation, rotating packed bed, dividing-wall columns and

  7. Enhanced vapor transport in membrane distillation via functionalized carbon nanotubes anchored into electrospun nanofibres

    KAUST Repository

    An, Alicia Kyoungjin; Lee, Eui-Jong; Guo, Jiaxin; Jeong, Sanghyun; Lee, Jung Gil; Ghaffour, NorEddine

    2017-01-01

    To ascertain membrane distillation (MD) as an emerging desalination technology to meet the global water challenge, development of membranes with ideal material properties is crucial. Functionalized carbon nanotubes (CNTs) were anchored to nanofibres of electrospun membranes. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer membrane, resulting in well-aligned CNTs inside crystalline fibres with superhydrophobicity. Consideration for the chemical/physical properties of the CNT composite membranes and calculation of their theoretical fluxes revealed the mechanism of MD: CNTs facilitated the repulsive force for Knudsen and molecular diffusions, reduced the boundary-layer effect in viscous flow, and assisted surface diffusion, allowing for fast vapor transport with anti-wetting. This study shows that the role of CNTs and an optimal composite ratio can be used to reduce the gap between theoretical and experimental approaches to desalination.

  8. Enhanced vapor transport in membrane distillation via functionalized carbon nanotubes anchored into electrospun nanofibres

    KAUST Repository

    An, Alicia Kyoungjin

    2017-01-30

    To ascertain membrane distillation (MD) as an emerging desalination technology to meet the global water challenge, development of membranes with ideal material properties is crucial. Functionalized carbon nanotubes (CNTs) were anchored to nanofibres of electrospun membranes. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer membrane, resulting in well-aligned CNTs inside crystalline fibres with superhydrophobicity. Consideration for the chemical/physical properties of the CNT composite membranes and calculation of their theoretical fluxes revealed the mechanism of MD: CNTs facilitated the repulsive force for Knudsen and molecular diffusions, reduced the boundary-layer effect in viscous flow, and assisted surface diffusion, allowing for fast vapor transport with anti-wetting. This study shows that the role of CNTs and an optimal composite ratio can be used to reduce the gap between theoretical and experimental approaches to desalination.

  9. Development and pilot testing of full-scale membrane distillation modules for deployment of waste heat

    NARCIS (Netherlands)

    Jansen, A.E.; Assink, J.W.; Hanemaaijer, J.H.; Medevoort, J. van; Sonsbeek, E. van

    2013-01-01

    Membrane distillation is an attractive technology for extracting fresh water from seawater. Newly developed modules have been used in pilot tests and bench scale tests to demonstrate the potential of producing excellent product water quality in a single step, little need for water pretreatment and a

  10. Carbon nanotube enhanced membrane distillation for online preconcentration of trace pharmaceuticals in polar solvents.

    Science.gov (United States)

    Gethard, Ken; Mitra, Somenath

    2011-06-21

    Carbon nanotube enhanced membrane distillation (MD) is presented as a novel, online analytical preconcentration method for removing polar solvents thereby concentrating the analytes, making this technique an alternate to conventional thermal evaporation. In a carbon nanotube immobilized membrane (CNIM), the CNTs serve as sorbent sites and provide additional pathways for enhanced solvent vapor transport, thus enhancing preconcentration. Enrichment using CNIM doubled compared to membranes without CNTs, while the methanol flux and mass transfer coefficients increased by 61% and 519% respectively. The carbon nanotube enhanced MD process showed excellent precision (RSD of 3-5%), linearity, and the detection limits were in the range of 0.001 to 0.009 mg L(-1) by HPLC analysis.

  11. The Effect of Non-condensable Gases Removal on Air Gap Membrane Distillation: Experimental and Simulation Studies

    KAUST Repository

    Alsaadi, Ahmad S.

    2014-01-01

    -based technologies and holds the potential of being a cost-effective separation process that can utilize low-grade waste heat or renewable energy. MD has four different configurations; among them is Air Gap Membrane Distillation (AGMD) which is the second most

  12. A new-generation asymmetric multi-bore hollow fiber membrane for sustainable water production via vacuum membrane distillation.

    Science.gov (United States)

    Wang, Peng; Chung, Tai-Shung

    2013-06-18

    Due to the growing demand for potable water, the capacities for wastewater reclamation and saline water desalination have been increasing. More concerns are raised on the poor efficiency of removing certain contaminants by the current water purification technologies. Recent studies demonstrated superior separation performance of the vacuum membrane distillation (VMD) technology for the rejection of trace contaminants such as boron, dye, endocrine-disruptive chemical, and chloro-compound. However, the absence of suitable membranes with excellent wetting resistance and high permeation flux has severely hindered the VMD application as an effective water production process. This work presents a new generation multibore hollow fiber (MBF) membrane with excellent mechanical durability developed for VMD. Its micromorphology was uniquely designed with a tight surface and a fully porous matrix to maximize both high wetting resistance and permeation flux. Credit to the multibore configuration, a 65% improvement was obtained on the antiwetting property. Using a synthetic seawater feed, the new membrane with optimized fabrication condition exhibits a high flux and the salt rejection is consistently greater than 99.99%. In addition, a comparison of 7-bore and 6-bore MBF membranes was performed to investigate the optimum geometry design. The newly designed MBF membrane not only demonstrates its suitability for VMD but also makes VMD come true as an efficient process for water production.

  13. Detection of trace fluoride in serum and urine by online membrane-based distillation coupled with ion chromatography.

    Science.gov (United States)

    Lou, Chaoyan; Guo, Dandan; Wang, Nani; Wu, Shuchao; Zhang, Peimin; Zhu, Yan

    2017-06-02

    An online membrane-based distillation (MBD) coupled with ion chromatography (IC) method was proposed for automatic detection of trace fluoride (F - ) in serum and urine samples. The system consisted of a sample vessel, a lab-made membrane module and an ion chromatograph. Hydrophobic polytetrafluoroethylene (PTFE) hollow fiber membrane was used in MBD which was directly performed in serum and urine samples to eliminate the matrix interferences and enrich fluoride, while enabling automation. The determination of fluoride in biological samples was carried out by IC with suppressed conductometric detection. The proposed method feasibly determined trace fluoride in serum and urine matrices with the optimized parameters, such as acid concentration, distillation temperature, and distillation time, etc. Fluoride exhibited satisfactory linearity in the range of 0.01-5.0mg/L with a correlation coefficient of 0.9992. The limit of detection (LOD, S/N=3) and limit of quantification (LOQ, S/N=10) were 0.78μg/L and 2.61μg/L, respectively. The relative standard deviations of peak area and peak height were all less than 5.15%. The developed method was validated for the determination of fluoride in serum and urine with good spiked recoveries ranging between 97.1-101.9%. This method also can be proposed as a suitable alternative for the analysis of fluoride in other complex biological samples. Copyright © 2017. Published by Elsevier B.V.

  14. No Evidence for Spontaneous Lipid Transfer at ER-PM Membrane Contact Sites.

    Science.gov (United States)

    Merklinger, Elisa; Schloetel, Jan-Gero; Spitta, Luis; Thiele, Christoph; Lang, Thorsten

    2016-04-01

    Non-vesicular lipid transport steps play a crucial role in lipid trafficking and potentially include spontaneous exchange. Since membrane contact facilitates this lipid transfer, it is most likely to occur at membrane contact sites (MCS). However, to date it is unknown whether closely attached biological membranes exchange lipids spontaneously. We have set up a system for studying the exchange of lipids at MCS formed between the endoplasmic reticulum (ER) and the plasma membrane. Contact sites were stably anchored and the lipids cholesterol and phosphatidylcholine (PC) were not capable of transferring spontaneously into the opposed bilayer. We conclude that physical contact between two associated biological membranes is not sufficient for transfer of the lipids PC and cholesterol.

  15. Effect of operating parameters and membrane characteristics on air gap membrane distillation performance for the treatment of highly saline water

    KAUST Repository

    Xu, Jingli

    2016-04-07

    In this study, ten different commercially available PTFE, PP and PVDF membranes were tested in desalination of highly saline water by air gap membrane distillation (AGMD). Process performance was investigated under different operating parameters, such as feed temperatures, feed flow velocities and salt concentrations reaching 120 g/L, and different membrane characteristics, such as membrane material, thickness, pore size and support layer, using a locally designed and fabricatd AGMD module and spacer. Results showed that increasing feed temperature increases permeate flux regardless of the feed concentration. However, feed flow velocity does not significantly affect the flux, especially at low feed temperatures. The PP membrane showed a better performance than the PVDF and PTFE membranes. Permeate flux decreases with the increase of salt concentration of feed solution, especially at higher concentrations above 90 g/L. The existence of membrane support layer led to a slight decrease of permeate flux. Membranes with pore sizes of 0.2 and 0.45 μm gave the best performance. Smaller pore size led to lower flux and larger pore size led to pore wetting due to lower LEP values. The effect of concentration polarization and temperature polarization has also been studied and compared.

  16. Membrane technologies for liquid radioactive waste treatment

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Harasimowicz, M.; Zakrzewska-Trznadel, G.

    1998-01-01

    At Institute of Nuclear Chemistry and Technology (INCT) the membrane method for purification of radioactive wastes applied such processes as ultrafiltration (UF), 'seeded' ultrafiltration and reverse osmosis (RO) was developed. On the basis of the results obtained in laboratory experiments the pilot plant for radioactive effluents treatment was built. The plant was composed of UF unit (AMICON H 26P30 capillary module) and two RO units (NITTO NTR 739 HF S-4 spiral wound LPRO modules). The capacity of the pilot plant was up to 200 L/h and the specific activity of wastes purified in the system - below 10 4 Bq/L. Decontamination factor for entire system is higher than 5 x10 3 . Another possibility for radioactive wastes treatment is membrane distillation (MD), non-isothermal process employing hydrophobic polymer membrane, which is developed at INCT now. Preliminary tests with liquid radwaste were carried out on laboratory unit with permeation test-cell holding flat sheet membrane. As a hydrophobic barrier membranes made of two polymers were used: polytetrafluoroethylene (PTFE) and polypropylene (PP). The process was arranged in direct contact membrane distillation configuration. The permeate condensed directly in the cold stream (distilled water) and retentate was enriched in radionuclides. The further experiments carried out with capillary module BFMF 06-30-33 (Euro-Sep Ltd.) with polypropylene capillaries, diameter 0.33 mm and cut off 0.6 μm proved previous results. A pilot plant employing GORE-TEX membrane distillation was constructed. The plant can clean the low-level radioactive wastes from nuclear centre, at a throughput about 0.05 m 3 /h

  17. Olefins-selective asymmetric carbon molecular sieve hollow fiber membranes for hybrid membrane-distillation processes for olefin/paraffin separations

    KAUST Repository

    Xu, Liren

    2012-12-01

    In this paper, the development of asymmetric carbon molecular sieve (CMS) hollow fiber membranes and advanced processes for olefin/paraffin separations based on the CMS membranes are reported. Membrane-based olefin/paraffin separations have been pursued extensively over the past decades. CMS membranes are promising to exceed the performance upper bound of polymer materials and have demonstrated excellent stability for gas separations. Previously, a substructure collapse phenomenon was found in Matrimid ® precursor derived CMS fiber. To overcome the permeance loss due to the increased separation layer thickness, 6FDA-DAM and 6FDA/BPDA-DAM precursors were selected as potential new precursors for carbon membrane formation. Defect-free asymmetric 6FDA-DAM and 6FDA/BPDA-DAM hollow fibers were successfully fabricated from a dry-jet/wet-quench spinning process. Polymer rigidity, glass-rubber transition and asymmetric morphology were correlated. CMS hollow fiber membranes produced from 6FDA-polymer precursors showed significant improvement in permeance for ethylene/ethane and propylene/propane separations. Further studies revealed that the CMS membranes are olefins-selective, which means the membranes are able to effectively separate olefins (ethylene and propylene) from paraffins (ethane and propane). This unique feature of CMS materials enables advanced hybrid membrane-distillation process designs. By using the olefins-selective membranes, these new processes may provide advantages over previously proposed retrofitting concepts. Further applications of the membranes are explored for hydrocarbons processes. Significant energy savings and even reduced footprint may be achieved in olefins production units. © 2012 Elsevier B.V.

  18. Improving the Distillate Prediction of a Membrane Distillation Unit in a Trigeneration Scheme by Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Luis Acevedo

    2018-03-01

    Full Text Available An Artificial Neural Network (ANN has been developed to predict the distillate produced in a permeate gap membrane distillation (PGMD module with process operating conditions (temperatures at the condenser and evaporator inlets, and feed seawater flow. Real data obtained from experimental tests were used for the ANN training and further validation and testing. This PGMD module constitutes part of an isolated trigeneration pilot unit fully supplied by solar and wind energy, which also provides power and sanitary hot water (SHW for a typical single family home. PGMD production was previously estimated with published data from the MD module manufacturer by means of a new type in the framework of Trnsys® simulation within the design of the complete trigeneration scheme. The performance of the ANN model was studied and improved through a parametric study varying the number of neurons in the hidden layer, the number of experimental datasets and by using different activation functions. The ANN obtained can be easily exported to be used in simulation, control or process analysis and optimization. Here, the ANN was finally used to implement a new type to estimate the PGMD production of the unit by using the inlet parameters obtained by the complete simulation model of the trigeneration unit based on Renewable Energy Sources (RES.

  19. Low temperature destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    1938-07-05

    A process is given and apparatus is described for the destructive distillation at low temperature of coal, oil shale, and the like by subjection to the action of a stream of hot gases or superhearted steam, flowing in a closed circuit. Subsequent treatment of the distillation residues with a gas stream containing oxygen results in combustion of the carbon-containing material therein brings to a high temperature the solid residue, in which the process comprises subsequently contacting the hot solid residue with the fluid stream effecting the distillation.

  20. Cholesterol transfer at endosomal-organelle membrane contact sites.

    Science.gov (United States)

    Ridgway, Neale D; Zhao, Kexin

    2018-06-01

    Cholesterol is delivered to the limiting membrane of late endosomes by Niemann-Pick Type C1 and C2 proteins. This review summarizes recent evidence that cholesterol transfer from endosomes to the endoplasmic reticulum and other organelles is mediated by lipid-binding proteins that localize to membrane contact sites (MCS). LDL-cholesterol in the late endosomal/lysosomes is exported to the plasma membrane, where most cholesterol resides, and the endoplasmic reticulum, which harbors the regulatory complexes and enzymes that control the synthesis and esterification of cholesterol. A major advance in dissecting these cholesterol transport pathways was identification of frequent and dynamic MCS between endosomes and the endoplasmic reticulum, peroxisomes and plasma membrane. Positioned at these MCS are members of the oxysterol-binding protein (OSBP) and steroidogenic acute regulatory protein-related lipid-transfer family of lipid transfer proteins that bridge the opposing membranes and directly or indirectly mediate cholesterol transfer. OSBP-related protein 1L (ORP1L), ORP5 and ORP6 mediate cholesterol transfer to the endoplasmic reticulum that regulates cholesterol homeostasis. ORP1L and STARD3 also move cholesterol from the endoplasmic reticulum-to-late endosomal/lysosomes under low-cholesterol conditions to facilitate intraluminal vesicle formation. Cholesterol transport also occurs at MCS with peroxisomes and possibly the plasma membrane. Frequent contacts between organelles and the endo-lysosomal vesicles are sites for bidirectional transfer of cholesterol.

  1. Nonlinear Lyapunov-based boundary control of distributed heat transfer mechanisms in membrane distillation plant

    KAUST Repository

    Eleiwi, Fadi

    2015-07-01

    This paper presents a nonlinear Lyapunov-based boundary control for the temperature difference of a membrane distillation boundary layers. The heat transfer mechanisms inside the process are modeled with a 2D advection-diffusion equation. The model is semi-descretized in space, and a nonlinear state-space representation is provided. The control is designed to force the temperature difference along the membrane sides to track a desired reference asymptotically, and hence a desired flux would be generated. Certain constraints are put on the control law inputs to be within an economic range of energy supplies. The effect of the controller gain is discussed. Simulations with real process parameters for the model, and the controller are provided. © 2015 American Automatic Control Council.

  2. Modeling of air-gap membrane distillation process: A theoretical and experimental study

    KAUST Repository

    Alsaadi, Ahmad Salem

    2013-06-03

    A one dimensional (1-D) air gap membrane distillation (AGMD) model for flat sheet type modules has been developed. This model is based on mathematical equations that describe the heat and mass transfer mechanisms of a single-stage AGMD process. It can simulate AGMD modules in both co-current and counter-current flow regimes. The theoretical model was validated using AGMD experimental data obtained under different operating conditions and parameters. The predicted water vapor flux was compared to the flux measured at five different feed water temperatures, two different feed water salinities, three different air gap widths and two MD membranes with different average pore sizes. This comparison showed that the model flux predictions are strongly correlated with the experimental data, with model predictions being within +10% of the experimentally determined values. The model was then used to study and analyze the parameters that have significant effect on scaling-up the AGMD process such as the effect of increasing the membrane length, and feed and coolant flow rates. The model was also used to analyze the maximum thermal efficiency of the AGMD process by tracing changes in water production rate and the heat input to the process along the membrane length. This was used to understand the gain in both process production and thermal efficiency for different membrane surface areas and the resultant increases in process capital and water unit cost. © 2013 Elsevier B.V.

  3. Low temperature distillation

    Energy Technology Data Exchange (ETDEWEB)

    1937-07-21

    To distil mineral or organic material, the material is heated by means of a hot gas entering into contact with and traversing the material in a horizontal direction. The vertical retort is charged with material from the hopper and hot gases from the furnace after traversing the boiler enter the preheating zone, pass through the slots and charge therein and are educted through connection by the blower. The charge passes downwardly to the distillation zone wherein hot gases from the heater are passed via pipe and slots through the chambers and to the pipe controlled by the dampers. These gases are recycled by the fan through the heater and chamber, that portion of the gases corresponding to the amount of vapours evolved from the distillation being evacuated via the pipe to the condensing plant not shown. Steam and/or a limited quantity of water may be admitted to the distillation zone.

  4. Fouling development in direct contact membrane distillation: Non-invasive monitoring and destructive analysis

    KAUST Repository

    Fortunato, Luca; Jang, Yongsun; Lee, Jung Gil; Jeong, Sanghyun; Lee, Sangho; Leiknes, TorOve; Ghaffour, NorEddine

    2017-01-01

    of organic compounds and salts. Liquid chromatography with organic carbon detection (LC-OCD) analysis revealed the abundance of biopolymer in the fouling layer formed at the initial phase. In the second phase, formation of carbonate crystals on the membrane

  5. Smart membranes for monitoring membrane based desalination processes

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-10-12

    Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and/or impedance sensors) mounted on the porous surface. In another example, a membrane distillation (MD) process includes the membrane. Processing circuitry can be configured to monitor outputs of the plurality of sensors. The monitored outputs can be used to determine membrane degradation, membrane fouling, or to provide an indication of membrane replacement or cleaning. The sensors can also provide temperatures or temperature differentials across the porous surface, which can be used to improve modeling or control the MD process.

  6. Thermodynamic analysis of effects of contact angle on interfacial interactions and its implications for membrane fouling control.

    Science.gov (United States)

    Chen, Jianrong; Shen, Liguo; Zhang, Meijia; Hong, Huachang; He, Yiming; Liao, Bao-Qiang; Lin, Hongjun

    2016-02-01

    Concept of hydrophobicity always fails to accurately assess the interfacial interaction and membrane fouling, which calls for reliable parameters for this purpose. In this study, effects of contact angle on interfacial interactions related to membrane fouling were investigated based on thermodynamic analysis. It was found that, total interaction energy between sludge foulants and membrane monotonically decreases and increases with water and glycerol contact angle, respectively, indicating that these two parameters can be reliable indicators predicting total interaction energy and membrane fouling. Membrane roughness decreases interaction strength for over 20 times, and effects of membrane roughness on membrane fouling should consider water and glycerol contact angle on membrane. It was revealed existence of a critical water and glycerol contact angle for a given membrane bioreactor. Meanwhile, diiodomethane contact angle has minor effect on the total interaction, and cannot be regarded as an effective indicator assessing interfacial interactions and membrane fouling. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Nonlinear observer-based Lyapunov boundary control of distributed heat transfer mechanisms for membrane distillation plant

    KAUST Repository

    Eleiwi, Fadi

    2016-09-19

    This paper presents a nonlinear observer-based Lyapunov control for a membrane distillation (MD) process. The control considers the inlet temperatures of the feed and the permeate solutions as inputs, transforming it to boundary control process, and seeks to maintain the temperature difference along the membrane boundaries around a sufficient level to promote water production. MD process is modeled with advection diffusion equation model in two dimensions, where the diffusion and convection heat transfer mechanisms are best described. Model analysis, effective order reduction and parameters physical interpretation, are provided. Moreover, a nonlinear observer has been designed to provide the control with estimates of the temperature evolution at each time instant. In addition, physical constraints are imposed on the control to have an acceptable range of feasible inputs, and consequently, better energy consumption. Numerical simulations for the complete process with real membrane parameter values are provided, in addition to detailed explanations for the role of the controller and the observer. (C) 2016 Elsevier Ltd. All rights reserved.

  8. Lipid transfer proteins do their thing anchored at membrane contact sites… but what is their thing?

    Science.gov (United States)

    Wong, Louise H; Levine, Tim P

    2016-04-15

    Membrane contact sites are structures where two organelles come close together to regulate flow of material and information between them. One type of inter-organelle communication is lipid exchange, which must occur for membrane maintenance and in response to environmental and cellular stimuli. Soluble lipid transfer proteins have been extensively studied, but additional families of transfer proteins have been identified that are anchored into membranes by transmembrane helices so that they cannot diffuse through the cytosol to deliver lipids. If such proteins target membrane contact sites they may be major players in lipid metabolism. The eukaryotic family of so-called Lipid transfer proteins Anchored at Membrane contact sites (LAMs) all contain both a sterol-specific lipid transfer domain in the StARkin superfamily (related to StART/Bet_v1), and one or more transmembrane helices anchoring them in the endoplasmic reticulum (ER), making them interesting subjects for study in relation to sterol metabolism. They target a variety of membrane contact sites, including newly described contacts between organelles that were already known to make contact by other means. Lam1-4p target punctate ER-plasma membrane contacts. Lam5p and Lam6p target multiple contacts including a new category: vacuolar non-NVJ cytoplasmic ER (VancE) contacts. These developments confirm previous observations on tubular lipid-binding proteins (TULIPs) that established the importance of membrane anchored proteins for lipid traffic. However, the question remaining to be solved is the most difficult of all: are LAMs transporters, or alternately are they regulators that affect traffic more indirectly? © 2016 Authors; published by Portland Press Limited.

  9. Membrane Distillation and Applications for Water Purification in Thermal Cogeneration - A Prestudy

    Energy Technology Data Exchange (ETDEWEB)

    Chuanfeng Liu; Martin, Andrew [Royal Inst. of Technology, Stockholm (Sweden)

    2005-02-01

    Cost-effective, reliable, and energy efficient water treatment systems are an integral part of modern cogeneration facilities. Demineralized water is required for make-up water in district heating networks and in boilers. In addition, increasing attention has been paid to the treatment of flue gas condensate for possible recycling. A number of membrane technologies like reverse osmosis (RO) and electrode ionization (EDI) have been developed for the above applications. Besides these methods, membrane distillation (MD) is promising technology in this context. MD utilizes differences in vapor pressure to purify water via a hydrophobic membrane. The process can utilize district heat supply temperatures or low-grade steam, thus making it attractive for cogeneration applications. This investigation consists of a pre-study to evaluate the viability of membrane distillation as a new water treatment technology in cogeneration plants. Results obtained from the study will be used as an input to follow-on research, which may include the construction of a pilot plant. Target groups for this study include environmental engineers with particular interest in emerging water purification technologies. Specific elements of this work include a literature survey, theoretical considerations of heat and mass transfer, and scale-up of experimental results. Data obtained from the test facility owned by Xzero AB and located at Royal Inst. of Technology was employed for this purpose. Actual water production was found to be lower than the theoretical maximum, illustrating the potential for improvements in MD module design. A case study considering a 10 m{sup 3} pure water/hr system is explored to shed light on commercial-scale aspects. Results show that MD is a promising alternative to RO in existing or new treatment facilities. The most favorable results were obtained for alternatives where either the district heat supply line or low-grade steam (2-3 bar, 200 deg C) are available. Specific

  10. A Feasibility Study of Ammonia Recovery from Coking Wastewater by Coupled Operation of a Membrane Contactor and Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Po-Hsun Lin

    2018-03-01

    Full Text Available More than 80% of ammonia (NH3 in the steel manufacturing process wastewater is contributed from the coking wastewater, which is usually treated by biological processes. However, the NH3 in the coking wastewater is typically too high for biological treatment due to its inhibitory concentration. Therefore, a two-stage process including a hollow fiber membrane contactor (HFMC and a modified membrane distillation (MD system was developed and applied to reduce and recover NH3 from coking wastewater. The objectives of this paper are to evaluate different membrane materials, receiving solutions, and operation parameters for the system, remove NH3 from the coking wastewater to less than 300 mg N/L, which is amenable to the biological process, and recover ammonia solution for reuse. As a result, the polytetrafluoroethylene (PTFE HFMC using sulfuric acid as a receiving solution can achieve a maximum NH3-N transmembrane flux of 1.67 g N/m2·h at pH of 11.5 and reduce NH3 in the coking wastewater to less than 300 mg N/L. The NH3 in the converted ammonium sulfate ((NH42SO4 was then recovered by the modified MD using ice water as the receiving solution to produce ≥3% of ammonia solution for reuse.

  11. Total water production capacity inversion phenomenon in multi-stage direct contact membrane distillation: A theoretical study

    KAUST Repository

    Lee, Jung Gil; Alsaadi, Ahmad Salem; Karam, Ayman M.; Francis, Lijo; Soukane, Sofiane; Ghaffour, NorEddine

    2017-01-01

    , which was confirmed by using two different mathematical models validated experimentally, was found to take place due to the decrease in water vapor flux across the membrane as well as the increase in heat loss by conduction as the membrane length

  12. Hg removal and the effects of coexisting metals in forward osmosis and membrane distillation.

    Science.gov (United States)

    Wu, Chia-Yu; Chen, Shiao-Shing; Zhang, Dai-Zhou; Kobayashi, Jun

    2017-06-01

    In this study, we investigate the rejection of Hg, Cd, and Pb and the effect of coexisting metals on Hg removal through forward osmosis (FO) and membrane distillation (MD) in order to establish a more effective water treatment process. The results of our laboratory experiment indicate that more than 97% of the rejection for each metal is achieved through the FO system, and this rejection is the highest among previous studies using membrane filtrations. Moreover, we examine the matrix effect of the coexisting Cd and Pb on the rejection of Hg in the FO system. Hg 2+ rejection increases with increase in the concentration of the coexisting metals. Furthermore, we study the effect of the Hg concentration and the water temperature on rejection of Hg 2+ . Indeed, the rejection of Hg 2+ is achieved above 95% under any condition. However, approximately 1-10 ppb Hg from the feed solution remains in the draw solution due to permeation. Therefore, we use a FO-MD hybrid system. Approximately 100% rejection of Hg 2+ and a stable water flux are achieved. Thus, the FO-MD hybrid system is considered an important alternative to previous studies using membrane filtration for heavy metals removal.

  13. Nonlinear observer to estimate polarization phenomenon in membrane distillation

    Directory of Open Access Journals (Sweden)

    Khoukhi Billal

    2015-01-01

    Full Text Available This paper presents a bi-dimensional dynamic model of Direct Contact Membrane Desalination (DCMD process. Most of the MD configuration processes have been modeled as steady-state one-dimensional systems. Stationary two-dimensional MD models have been considered only in very few studies. In this work, a dynamic model of a DCMD process is developed. The model is implemented using Matlab/Simulink environment. Numerical simulations are conducted for different operational parameters at the module inlets such as the feed and permeate temperature or feed and permeate flow rate. The results are compared with experimental data published in the literature. The work presents also a feed forward control that compensates the possible decrease of the temperature gradient by increasing the flow rate. This work also deals with a development of nonlinear observer to estimate temperature polarization inside the membrane. The observer gives a good profile and longitudinal temperature estimations and shows a good prediction of pure water flux production.

  14. Does osmotic distillation change the isotopic relation of wines?

    Directory of Open Access Journals (Sweden)

    Schmitt Matthias

    2014-01-01

    Full Text Available Currently partial alcohol reduction of wine is in the focus of research worldwide. There are several technologies available to achieve this target. These techniques are either based on distilling or membrane processes. Osmotic distillation, one of the possibilities, is a quite modern membrane process that can be used. During that process, wine is pumped in counter flow to water along a micro porous, hydrophobic membrane. The volatile components of the wine can permeate that membrane and are dissolved in water. The driving force of that process is the vapor pressure difference between the volatiles on the wine and water side of the membrane. The aim of this work was to determine if the alcohol reduction by osmotic distillation can change the isotopic relation in a wine. Can this enological practice change the composition of a wine in a way that an illegal water addition is simulated? Different wines were reduced by 2% alcohol v/v with varying process parameters. The isotopic analysis of the O 16/18 ratio in the wine were performed according to the OIV methods (353/2009 These analyses showed that the isotopic ratio is modified by an alcohol reduction of 2% v/v in a way that corresponds to an addition of 4–5% of external water.

  15. Continuous fractional distillation of petroleum

    Energy Technology Data Exchange (ETDEWEB)

    1921-11-05

    This invention has for its object a process of distillation, fractional, and continuous, of shale oil, tar, etc., characterized by the vapors leaving the evaporation chamber being forced, before condensation, to go over a continuous circuit. The vapors traverse first a preheater then return to the vaporization chamber in which they are passed along large surfaces and by application of the counter-current principle in contact with the liquid to be distilled. They stream through the chamber in a continuous manner (the quantity of vapor emitted in the circuit being determined in a manner to advance the distillation just to completion); the excess of vapor formed being removed from the circuit and sent to a condensing apparatus for fractionation.

  16. Smart membranes for monitoring membrane based desalination processes

    KAUST Repository

    Laleg-Kirati, Taous-Meriem; Karam, Ayman M.

    2017-01-01

    Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and

  17. Evaluation of hydroacid complex in the forward osmosis–membrane distillation (FO–MD) system for desalination

    KAUST Repository

    Wang, Peng; Cui, Yue; Ge, Qingchun; Fern Tew, Tjin; Chung, Neal Tai-Shung

    2015-01-01

    The incorporation of membrane distillation (MD) into forward osmosis (FO) provides process sustainability to regenerate the draw solution and to produce clean water simultaneously. However, the reverse salt flux is the major hurdle in the FO-MD system because it not only reduces the effective osmotic driving force across the membrane but also increases the replenishment cost and scaling issue. For the first time, a hydroacid complex with abundant hydrophilic groups and ionic species is evaluated as the draw solutes in the hybrid FO-MD system consisting of multi-bore PVDF MD membranes for seawater/brackish desalination. In order to evaluate the practicality of the hydroacid complex in the FO-MD system, FO and MD experiments were conducted at elevated temperatures and concentrations. The hydroacid complex has displayed desired properties such as high solubility, low viscosity, excellent thermal stability and minimal reverse salt flux suitable for FO and MD operations. FO-MD desalination process was demonstrated with a highest seawater desalination flux of 6/32 LMH (FO/MD). This study may open up the prospective of employing the hydroacid complex as the draw solute in FO-MD hybrid systems for seawater /brackish desalination. © 2015 Elsevier B.V.

  18. Evaluation of hydroacid complex in the forward osmosis–membrane distillation (FO–MD) system for desalination

    KAUST Repository

    Wang, Peng

    2015-11-01

    The incorporation of membrane distillation (MD) into forward osmosis (FO) provides process sustainability to regenerate the draw solution and to produce clean water simultaneously. However, the reverse salt flux is the major hurdle in the FO-MD system because it not only reduces the effective osmotic driving force across the membrane but also increases the replenishment cost and scaling issue. For the first time, a hydroacid complex with abundant hydrophilic groups and ionic species is evaluated as the draw solutes in the hybrid FO-MD system consisting of multi-bore PVDF MD membranes for seawater/brackish desalination. In order to evaluate the practicality of the hydroacid complex in the FO-MD system, FO and MD experiments were conducted at elevated temperatures and concentrations. The hydroacid complex has displayed desired properties such as high solubility, low viscosity, excellent thermal stability and minimal reverse salt flux suitable for FO and MD operations. FO-MD desalination process was demonstrated with a highest seawater desalination flux of 6/32 LMH (FO/MD). This study may open up the prospective of employing the hydroacid complex as the draw solute in FO-MD hybrid systems for seawater /brackish desalination. © 2015 Elsevier B.V.

  19. Method of distillation of bituminous material

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, E G.T.

    1919-11-12

    A method is described of dry distillation of bituminous materials by leading warm combustible gases, mixed or not mixed with steam, through the distillation chamber in direct contact with the materials, during which process the distillation chamber may be heated by other means. It is characterized by the mixture of distillation products (formed by the vapors produced by heating the raw materials) and the gas (circulating gas) used for heating in the process, being led through coolers or similar contrivances, in order to separate through condensation the greater part of the content of the products or materials condensable at ordinary temperatures, and also to recover as much as possible of the highly volatile oils in the gas. Thereafter the gas is split, one part is, without further cleaning, and led through the distillation chamber, after this gas has been reheated in suitable apparatus. The other part (surplus gas), which in volume corresponds approximately to the new-formed distillation gases, is treated according to known methods for the extraction of the remaining products of the distillation, such as volatile oils, ammonia, methyl alcohol, sulfuretted hydrogen, and others. The patent contains three other claims.

  20. Sweeping Gas Membrane Desalination Using Commercial Hydrophobic Hollow Fiber Membranes; TOPICAL

    International Nuclear Information System (INIS)

    EVANS, LINDSEY; MILLER, JAMES E.

    2002-01-01

    Water shortages affect 88 developing countries that are home to half of the world's population. In these places, 80-90% of all diseases and 30% of all deaths result from poor water quality. Furthermore, over the next 25 years, the number of people affected by severe water shortages is expected to increase fourfold. Low cost methods of purifying freshwater, and desalting seawater are required to contend with this destabilizing trend. Membrane distillation (MD) is an emerging technology for separations that are traditionally accomplished via conventional distillation or reverse osmosis. As applied to desalination, MD involves the transport of water vapor from a saline solution through the pores of a hydrophobic membrane. In sweeping gas MD, a flowing gas stream is used to flush the water vapor from the permeate side of the membrane, thereby maintaining the vapor pressure gradient necessary for mass transfer. Since liquid does not penetrate the hydrophobic membrane, dissolved ions are completely rejected by the membrane. MD has a number of potential advantages over conventional desalination including low temperature and pressure operation, reduced membrane strength requirements, compact size, and 100% rejection of non-volatiles. The present work evaluated the suitability of commercially available technology for sweeping gas membrane desalination. Evaluations were conducted with Celgard Liqui-Cel(reg s ign) Extra-Flow 2.5X8 membrane contactors with X-30 and X-40 hydrophobic hollow fiber membranes. Our results show that sweeping gas membrane desalination systems are capable of producing low total dissolved solids (TDS) water, typically 10 ppm or less, from seawater, using low grade heat. However, there are several barriers that currently prevent sweeping gas MD from being a viable desalination technology. The primary problem is that large air flows are required to achieve significant water yields, and the costs associated with transporting this air are prohibitive. To

  1. Fractional distillation of oil

    Energy Technology Data Exchange (ETDEWEB)

    Jones, L D

    1931-10-31

    A method of dividing oil into lubricating oil fractions without substantial cracking by introducing the oil in a heated state into a fractionating column from which oil fractions having different boiling points are withdrawn at different levels, while reflux liquid is supplied to the top of the column, and additional heat is introduced into the column by contacting with the oil therein a heated fluid of higher monlecular weight than water and less susceptible to thermal decomposition than is the highest boiling oil fraction resulting from the distillation, or of which any products produced by thermal decomposition will not occur in the highest boiling distillate withdrawn from the column.

  2. An advanced online monitoring approach to study the scaling behavior in direct contact membrane distillation

    KAUST Repository

    Lee, Jung Gil; Jang, Yongsun; Fortunato, Luca; Jeong, Sanghyun; Lee, Sangho; Leiknes, TorOve; Ghaffour, NorEddine

    2017-01-01

    scaling was performed by using various analytical methods, especially an in-situ monitoring technique using an optical coherence tomography (OCT) to observe the cross-sectional view on the membrane surface during operation. Different concentrations of Ca

  3. The role of phosphatidylinositol-transfer proteins at membrane contact sites.

    Science.gov (United States)

    Selitrennik, Michael; Lev, Sima

    2016-04-15

    Phosphatidylinositol-transfer proteins (PITPs) have been initially identified as soluble factors that accelerate the monomeric exchange of either phosphatidylinositol (PI) or phosphatidylcholine (PC) between membrane bilayersin vitro They are highly conserved in eukaryotes and have been implicated in different cellular processes, including vesicular trafficking, signal transduction, and lipid metabolism. Recent studies suggest that PITPs function at membrane contact sites (MCSs) to facilitate the transport of PI from its synthesis site at the endoplasmic reticulum (ER) to various membrane compartments. In this review, we describe the underlying mechanism of PITPs targeting to MCSs, discuss their cellular roles and potential mode of action. © 2016 Authors; published by Portland Press Limited.

  4. Membrane/distillation hybrid process research and development. Final report, phase II

    Energy Technology Data Exchange (ETDEWEB)

    Mazanec, T.J.

    1997-07-01

    This report covers work conducted under the grant awarded to BP by DOE in late 1991 entitled {open_quotes}Membrane/Distillation Hybrid Process Research and Development.{close_quotes} The program was directed towards development and commercialization of the BP process for separation of vapor phase olefins from non-olefins via facilitated transport using an aqueous facilitator. The program has come to a very successful conclusion, with formation of a partnership between BP and Stone and Webster Engineering Corporation (SWEC) to market and commercialize the technology. The focus of this report is the final portion of the program, during which engineering re-design, facilitator optimization, economic analysis, and marketing have been the primary activities. At the end of Phase II BP was looking to partner with an engineering firm to advance the selective olefin recovery (SOR) technology from the lab/demo stage to full commercialization. In August 1995 BP and SWEC reached an agreement to advance the technology by completing additional Phase III work with DOE and beginning marketing activities.

  5. Novel, one-step synthesis of zwitterionic polymer nanoparticles via distillation-precipitation polymerization and its application for dye removal membrane.

    Science.gov (United States)

    Ibrahim, G P Syed; Isloor, Arun M; Inamuddin; Asiri, Abdullah M; Ismail, Norafiqah; Ismail, Ahmed Fauzi; Ashraf, Ghulam Md

    2017-11-21

    In this work, poly(MBAAm-co-SBMA) zwitterionic polymer nanoparticles were synthesized in one-step via distillation-precipitation polymerization (DPP) and were characterized. [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) as monomer and N, N'-methylene bis(acrylamide) (MBAAm) as cross-linker are used for the synthesis of nanoparticles. As  far as our knowledge, this is the first such report on the synthesis of poly(MBAAm-co-SBMA) nanoparticles via DPP. The newly synthesized nanoparticles were further employed for the surface modification of polysulfone (PSF) hollow fiber membranes for dye removal. The modified hollow fiber membrane exhibited the improved permeability (56 L/ m 2 h bar) and dye removal (>98% of Reactive Black 5 and >80.7% of Reactive orange 16) with the high permeation of salts. Therefore, the as-prepared membrane can have potential application in textile and industrial wastewater treatment.

  6. Synthesis and fabrication of nanostructured hydrophobic polyazole membranes for low-energy water recovery

    KAUST Repository

    Maab, Husnul; Francis, Lijo; Alsaadi, Ahmad Salem; Aubry, Cyril; Ghaffour, NorEddine; Amy, Gary L.; Nunes, Suzana Pereira

    2012-01-01

    Aromatic fluorinated polyoxadiazoles (F-POD) and polytriazoles (F-PT) were synthesized and for the first time manufactured into porous membranes by phase inversion and by electrospinning. The phase inversion F-POD membranes had a mean flow pore size (MFP) of 51nm, while for F-PT it was around 74nm. The electrospun membranes had a much larger pore size, the MFP for F-POD membrane was around 1.7μm and for F-PT it was 2.7μm. The membranes were tested for desalination of Red Sea water using direct contact membrane distillation (DCMD). By combining the high polymer hydrophobicity and high porosity, apparent contact angles up to 162° were obtained, assuring the operation with practically no liquid water leakage under pressure up to 0.9bar. Salt selectivity as high as 99.95% and water fluxes as high as 85Lm -2h -1 were demonstrated, operating at 80°C feed temperature and 22°C permeate. © 2012 Elsevier B.V.

  7. Synthesis and fabrication of nanostructured hydrophobic polyazole membranes for low-energy water recovery

    KAUST Repository

    Maab, Husnul

    2012-12-01

    Aromatic fluorinated polyoxadiazoles (F-POD) and polytriazoles (F-PT) were synthesized and for the first time manufactured into porous membranes by phase inversion and by electrospinning. The phase inversion F-POD membranes had a mean flow pore size (MFP) of 51nm, while for F-PT it was around 74nm. The electrospun membranes had a much larger pore size, the MFP for F-POD membrane was around 1.7μm and for F-PT it was 2.7μm. The membranes were tested for desalination of Red Sea water using direct contact membrane distillation (DCMD). By combining the high polymer hydrophobicity and high porosity, apparent contact angles up to 162° were obtained, assuring the operation with practically no liquid water leakage under pressure up to 0.9bar. Salt selectivity as high as 99.95% and water fluxes as high as 85Lm -2h -1 were demonstrated, operating at 80°C feed temperature and 22°C permeate. © 2012 Elsevier B.V.

  8. Thermodynamic modelling of a membrane distillation crystallisation process for the treatment of mining wastewater.

    Science.gov (United States)

    Nathoo, Jeeten; Randall, Dyllon Garth

    2016-01-01

    Membrane distillation (MD) could be applicable in zero liquid discharge applications. This is due to the fact that MD is applicable at high salinity ranges which are generally outside the scope of reverse osmosis (RO) applications, although this requires proper management of precipitating salts to avoid membrane fouling. One way of managing these salts is with MD crystallisation (MDC). This paper focuses on the applicability of MDC for the treatment of mining wastewater by thermodynamically modelling the aqueous chemistry of the process at different temperatures. The paper is based on the typical brine generated from an RO process in the South African coal mining industry and investigates the effect water recovery and operating temperature have on the salts that are predicted to crystallise out, the sequence in which they will crystallise out and purities as a function of the water recovery. The study confirmed the efficacy of using thermodynamic modelling as a tool for investigating and predicting the crystallisation aspects of the MDC process. The key finding from this work was that, for an MDC process, a purer product can be obtained at higher operating temperatures and recoveries because of the inverse solubility of calcium sulphate.

  9. Investigation of force, contact area, and dwell time in finger-tapping tasks on membrane touch interface.

    Science.gov (United States)

    Liu, Na; Yu, Ruifeng

    2018-06-01

    This study aimed to determine the touch characteristics during tapping tasks on membrane touch interface and investigate the effects of posture and gender on touch characteristics variables. One hundred participants tapped digits displayed on a membrane touch interface on sitting and standing positions using all fingers of the dominant hand. Touch characteristics measures included average force, contact area, and dwell time. Across fingers and postures, males exerted larger force and contact area than females, but similar dwell time. Across genders and postures, thumb exerted the largest force and the force of the other four fingers showed no significant difference. The contact area of the thumb was the largest, whereas that of the little finger was the smallest; the dwell time of the thumb was the longest, whereas that of the middle finger was the shortest. Relationships among finger sizes, gender, posture and touch characteristics were proposed. The findings helped direct membrane touch interface design for digital and numerical control products from hardware and software perspectives. Practitioner Summary: This study measured force, contact area, and dwell time in tapping tasks on membrane touch interface and examined effects of gender and posture on force, contact area, and dwell time. The findings will direct membrane touch interface design for digital and numerical control products from hardware and software perspectives.

  10. Estimation of contact resistance in proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lianhong; Liu, Ying; Song, Haimin; Wang, Shuxin [School of Mechanical Engineering, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072 (China); Zhou, Yuanyuan; Hu, S. Jack [Department of Mechanical Engineering, The University of Michigan, Ann Arbor, MI 48109-2125 (United States)

    2006-11-22

    The contact resistance between the bipolar plate (BPP) and the gas diffusion layer (GDL) is an important factor contributing to the power loss in proton exchange membrane (PEM) fuel cells. At present there is still not a well-developed method to estimate such contact resistance. This paper proposes two effective methods for estimating the contact resistance between the BPP and the GDL based on an experimental contact resistance-pressure constitutive relation. The constitutive relation was obtained by experimentally measuring the contact resistance between the GDL and a flat plate of the same material and processing conditions as the BPP under stated contact pressure. In the first method, which was a simplified prediction, the contact area and contact pressure between the BPP and the GDL were analyzed with a simple geometrical relation and the contact resistance was obtained by the contact resistance-pressure constitutive relation. In the second method, the contact area and contact pressure between the BPP and GDL were analyzed using FEM and the contact resistance was computed for each contact element according to the constitutive relation. The total contact resistance was then calculated by considering all contact elements in parallel. The influence of load distribution on contact resistance was also investigated. Good agreement was demonstrated between experimental results and predictions by both methods. The simplified prediction method provides an efficient approach to estimating the contact resistance in PEM fuel cells. The proposed methods for estimating the contact resistance can be useful in modeling and optimizing the assembly process to improve the performance of PEM fuel cells. (author)

  11. Theoretical and experimental study of integrated membrane / distillation processes for industrial applications

    NARCIS (Netherlands)

    Perez, P.

    2007-01-01

    In industrial practice the separation of an azeotropic mixture usually involves adding a third component to the distillation process to break the azeotrope. The major disadvantages of this so called azeotropic and extractive distillation are the relatively high capital and high energy costs and the

  12. Sustainable water recovery from oily wastewater via forward osmosis-membrane distillation (FO-MD).

    Science.gov (United States)

    Zhang, Sui; Wang, Peng; Fu, Xiuzhu; Chung, Tai-Shung

    2014-04-01

    This study proposed and investigated a hybrid forward osmosis - membrane distillation (FO-MD) system for sustainable water recovery from oily wastewater by employing lab-fabricated FO and MD hollow fiber membranes. Stable oil-in-water emulsions of different concentrations with small droplet sizes (oil droplets and partial permeation of acetic acid could be achieved. Finally, an integrated FO-MD system was developed to treat the oily wastewater containing petroleum, surfactant, NaCl and acetic acid at 60 °C in the batch mode. The water flux in FO undergoes three-stage decline due to fouling and reduction in osmotic driving force, but is quite stable in MD regardless of salt concentration. Oily wastewater with relatively high salinity could be effectively recovered by the FO-MD hybrid system while maintaining large water flux, at least 90% feed water recovery could be readily attained with only trace amounts of oil and salts, and the draw solution was re-generated for the next rounds of FO-MD run. Interestingly, significant amount of acetic acid was also retained in the permeate for further reuse as a chemical additive during the production of crude oil. The work has demonstrated that not only water but also organic additives in the wastewater could be effectively recovered by FO-MD systems for reuse or other utilizations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Multi-objective Optimization of Solar-driven Hollow-fiber Membrane Distillation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Nenoff, Tina M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Moore, Sarah E. [Univ. of Arizona, Tucson, AZ (United States); Mirchandani, Sera [Univ. of Arizona, Tucson, AZ (United States); Karanikola, Vasiliki [Univ. of Arizona, Tucson, AZ (United States); Arnold, Robert G. [Univ. of Arizona, Tucson, AZ (United States); Saez, Eduardo [Univ. of Arizona, Tucson, AZ (United States)

    2017-09-01

    Securing additional water sources remains a primary concern for arid regions in both the developed and developing world. Climate change is causing fluctuations in the frequency and duration of precipitation, which can be can be seen as prolonged droughts in some arid areas. Droughts decrease the reliability of surface water supplies, which forces communities to find alternate primary water sources. In many cases, ground water can supplement the use of surface supplies during periods of drought, reducing the need for above-ground storage without sacrificing reliability objectives. Unfortunately, accessible ground waters are often brackish, requiring desalination prior to use, and underdeveloped infrastructure and inconsistent electrical grid access can create obstacles to groundwater desalination in developing regions. The objectives of the proposed project are to (i) mathematically simulate the operation of hollow fiber membrane distillation systems and (ii) optimize system design for off-grid treatment of brackish water. It is anticipated that methods developed here can be used to supply potable water at many off-grid locations in semi-arid regions including parts of the Navajo Reservation. This research is a collaborative project between Sandia and the University of Arizona.

  14. Osmotically and thermally isolated forward osmosis-membrane distillation (fo-md) integrated module for water treatment applications

    KAUST Repository

    Ghaffour, Noreddine

    2016-09-01

    An integrated forward osmosis-membrane distillation (FO-MD) module and systems and methods incorporating the module is disclosed providing higher efficiencies and using less energy. The FO-MD module is osmotically and thermally isolated. The isolation can prevent mixing of FO draw solution/FO permeate and MD feed, and minimize dilution of FO draw solution and cooling of MD feed. The module provides MD feed solution and FO draw solution streams that flow in the same module but are separated by an isolation barrier. The osmotically and thermally isolated FO-MD integrated module, systems and methods offer higher driving forces of both FO and MD processes, higher recovery, and wider application than previously proposed hybrid FO- MD systems.

  15. Osmotically and thermally isolated forward osmosis-membrane distillation (fo-md) integrated module for water treatment applications

    KAUST Repository

    Ghaffour, NorEddine; Francis, Lijo; Li, Zhenyu; Valladares, Rodrigo; Alsaadi, Ahmad S.; Ghdaib, Muhannad Abu; Amy, Gary L.

    2016-01-01

    An integrated forward osmosis-membrane distillation (FO-MD) module and systems and methods incorporating the module is disclosed providing higher efficiencies and using less energy. The FO-MD module is osmotically and thermally isolated. The isolation can prevent mixing of FO draw solution/FO permeate and MD feed, and minimize dilution of FO draw solution and cooling of MD feed. The module provides MD feed solution and FO draw solution streams that flow in the same module but are separated by an isolation barrier. The osmotically and thermally isolated FO-MD integrated module, systems and methods offer higher driving forces of both FO and MD processes, higher recovery, and wider application than previously proposed hybrid FO- MD systems.

  16. Ocean thermocline driven membrane distillation process

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad S.; Abraham, Raju

    2017-01-01

    source, or the energy cost of the heating source, to heat the feed stream to the membrane. In an aspect, the sensible heat present in surface seawater is used for the heat energy for the warm stream fed to the membrane, and deep seawater is used

  17. Application of carbon-coated TiO2 for decomposition of methylene blue in a photocatalytic membrane reactor

    International Nuclear Information System (INIS)

    Mozia, Sylwia; Toyoda, Masahiro; Inagaki, Michio; Tryba, Beata; Morawski, Antoni W.

    2007-01-01

    An application of carbon-coated TiO 2 for decomposition of methylene blue (MB) in a photocatalytic membrane reactor (PMR), coupling photocatalysis and direct contact membrane distillation (DCMD) was investigated. Moreover, photodegradation of a model pollutant in a batch reactor without membrane distillation (MD) was also examined. Carbon-modified TiO 2 catalysts containing different amount of carbon and commercially available TiO 2 (ST-01) were used in this study. The carbon-coated catalyst prepared from a mixture of ST-01 and polyvinyl alcohol in the mass ratio of 70/30 was the most effective in degradation of MB from all of the photocatalysts applied. Photodecomposition of MB on the recovered photocatalysts was lower than on the fresh ones. The photodegradation of MB in the PMR was slower than in the batch reactor, what probably resulted from shorter time of exposure of the catalyst particles to UV irradiation. The MD process could be successfully applied for separation of photocatalyst and by-products from the feed solution

  18. Cleaning results of new and fouled nanofiltration membrane characterized by contact angle, updated DSPM, flux and salts rejection

    International Nuclear Information System (INIS)

    Al-Amoudi, Ahmed; Williams, Paul; Al-Hobaib, A.S.; Lovitt, Robert W.

    2008-01-01

    In membrane process industries, membrane cleaning is one of the most important concerns from both economical and scientific points of view. Though cleaning is important to recover membrane performance, an inappropriate selection of cleaning agents may result into unsatisfactory cleaning or irreparable membrane. In this study the cleaning performance has been studied with measurements of membrane contact angle, Updated Donnan steric partitioning pore model (UDSPM) and salt rejection as well as flux measurement. Thin film nanofiltration (NF) membranes such as DK, HL and DL provided by GE Osmonics are used in this study. Tests were carried out with virgin DK, HL and DL as well as fouled DK membranes. Several cleaning agents were investigated; some of them were analytical grade such as HCl, NaOH and others such as SDS, mix agents were commercial grade agents that are already in use in commercial plants. Contact angle, DSPM and salt rejection as well as flux of virgin and fouled membranes before and after chemical cleaning were measured and compared. The contact angle measurements with and without chemical cleaning of different virgin and fouled membranes revealed very interesting results which may be used to characterise the membrane surface cleanliness. The contact angle results revealed that the cleaning agents are found to modify membrane surface properties (hydrophobicity/hydrophilicity) of the treated and untreated virgin and fouled membranes. The details of these results were also investigated and are reported in the paper. However, UDSPM method did not give any valuable information about pore size of the untreated and treated NF membranes. The salt rejection level of monovalent and divalent ions before and after cleaning by high and low pH cleaning agents is also investigated and is reported in the paper

  19. Cleaning results of new and fouled nanofiltration membrane characterized by contact angle, updated DSPM, flux and salts rejection

    Energy Technology Data Exchange (ETDEWEB)

    Al-Amoudi, Ahmed [Centre for complex fluids processing, Multidisciplinary Nanotechnology Centre, School of Engineering, University of Wales, Swansea SA2 8PP (United Kingdom) and Saline Water Conversion Corporation (SWCC), Saline Water Desalination Research Institute Staff (Saudi Arabia)], E-mail: 310981@swan.ac.uk; Williams, Paul [Centre for complex fluids processing, Multidisciplinary Nanotechnology Centre, School of Engineering, University of Wales, Swansea SA2 8PP (United Kingdom); Al-Hobaib, A.S. [Institute of Atomic Energy Research, King Abdulaziz City for Science And Technology, P.O. Box 6086, Riyadh 11442 (Saudi Arabia); Lovitt, Robert W. [Centre for complex fluids processing, Multidisciplinary Nanotechnology Centre, School of Engineering, University of Wales, Swansea SA2 8PP (United Kingdom)

    2008-04-30

    In membrane process industries, membrane cleaning is one of the most important concerns from both economical and scientific points of view. Though cleaning is important to recover membrane performance, an inappropriate selection of cleaning agents may result into unsatisfactory cleaning or irreparable membrane. In this study the cleaning performance has been studied with measurements of membrane contact angle, Updated Donnan steric partitioning pore model (UDSPM) and salt rejection as well as flux measurement. Thin film nanofiltration (NF) membranes such as DK, HL and DL provided by GE Osmonics are used in this study. Tests were carried out with virgin DK, HL and DL as well as fouled DK membranes. Several cleaning agents were investigated; some of them were analytical grade such as HCl, NaOH and others such as SDS, mix agents were commercial grade agents that are already in use in commercial plants. Contact angle, DSPM and salt rejection as well as flux of virgin and fouled membranes before and after chemical cleaning were measured and compared. The contact angle measurements with and without chemical cleaning of different virgin and fouled membranes revealed very interesting results which may be used to characterise the membrane surface cleanliness. The contact angle results revealed that the cleaning agents are found to modify membrane surface properties (hydrophobicity/hydrophilicity) of the treated and untreated virgin and fouled membranes. The details of these results were also investigated and are reported in the paper. However, UDSPM method did not give any valuable information about pore size of the untreated and treated NF membranes. The salt rejection level of monovalent and divalent ions before and after cleaning by high and low pH cleaning agents is also investigated and is reported in the paper.

  20. Effects of thermal efficiency in DCMD and the preparation of membranes with low thermal conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhehao, E-mail: ccgri_lzh@163.com [Changchun Gold Research Institute, 130012 (China); Peng, Yuelian, E-mail: pyl@live.com.au [Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Dong, Yajun; Fan, Hongwei [Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Chen, Ping [The Research Institute of Environmental Protection, North China Pharmaceutical Group Corporation, 050015 (China); Qiu, Lin [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Jiang, Qi [National Major Science and Technology Program Management Office for Water Pollution Control and Treatment, MEP, 100029 (China)

    2014-10-30

    Highlights: • The effects on vapor flux and thermal efficiency were simulated. • The conditions favoring vapor flux also favored thermal efficiency. • Four microporous polymer membranes were compared. • The SiO{sub 2} aerogel coating reduced the thermal conductivity of polymer membranes. • A 3ω technique was used to measure the thermal conductivity of membranes. - Abstract: The effects of the membrane characteristics and operational conditions on the vapor flux and thermal efficiency in a direct contact membrane distillation (DCMD) process were studied with a mathematical simulation. The membrane temperature, driving force of vapor transfer, membrane distillation coefficient, etc. were used to analyze the effects. The operating conditions that increased the vapor flux improved the thermal efficiency. The membrane characteristics of four microporous membranes and their performances in DCMD were compared. A polysulfone (PSf) membrane prepared via vapor-induced phase separation exhibited the lowest thermal conductivity. The PSf and polyvinylidene difluoride (PVDF) membranes were modified using SiO{sub 2} aerogel blending and coating to reduce the thermal conductivity of the membrane. The coating process was more effective than the blending process toward this end. The changes in the structure of the modified membrane were observed with a scanning electron microscope. Si was found on the modified membrane surface with an energy spectrometer. The PVDF composite and support membranes were tested during the DCMD process; the composite membrane had a higher vapor flux and a better thermal efficiency than the support. A new method based on a 3ω technique was used to measure the thermal conductivity of the membranes.

  1. Effects of thermal efficiency in DCMD and the preparation of membranes with low thermal conductivity

    International Nuclear Information System (INIS)

    Li, Zhehao; Peng, Yuelian; Dong, Yajun; Fan, Hongwei; Chen, Ping; Qiu, Lin; Jiang, Qi

    2014-01-01

    Highlights: • The effects on vapor flux and thermal efficiency were simulated. • The conditions favoring vapor flux also favored thermal efficiency. • Four microporous polymer membranes were compared. • The SiO 2 aerogel coating reduced the thermal conductivity of polymer membranes. • A 3ω technique was used to measure the thermal conductivity of membranes. - Abstract: The effects of the membrane characteristics and operational conditions on the vapor flux and thermal efficiency in a direct contact membrane distillation (DCMD) process were studied with a mathematical simulation. The membrane temperature, driving force of vapor transfer, membrane distillation coefficient, etc. were used to analyze the effects. The operating conditions that increased the vapor flux improved the thermal efficiency. The membrane characteristics of four microporous membranes and their performances in DCMD were compared. A polysulfone (PSf) membrane prepared via vapor-induced phase separation exhibited the lowest thermal conductivity. The PSf and polyvinylidene difluoride (PVDF) membranes were modified using SiO 2 aerogel blending and coating to reduce the thermal conductivity of the membrane. The coating process was more effective than the blending process toward this end. The changes in the structure of the modified membrane were observed with a scanning electron microscope. Si was found on the modified membrane surface with an energy spectrometer. The PVDF composite and support membranes were tested during the DCMD process; the composite membrane had a higher vapor flux and a better thermal efficiency than the support. A new method based on a 3ω technique was used to measure the thermal conductivity of the membranes

  2. Process intensification on membrane-based process for blackcurrant juice concentration

    DEFF Research Database (Denmark)

    Fjerbæk Søtoft, Lene; Rong, Ben-Guang; Christensen, Knud Villy

    Juice concentrate production is a field where process intensification and novel concentration processes need to be implemented. The paper presents a systematic approach for process synthesis based on membrane processes for the concentration of blackcurrant juice, exemplified by the aroma recovery...... using combinations of vacuum membrane distillation and traditional distillation. Furthermore, the paper further suggests a novel method for the combination of nanofiltration, reverse osmosis and membrane distillation for the concentration of the dearomatized juice....

  3. Concentration of phenolic acids and flavonoids in aronia melanocarpa (choke berry) juice by osmotic membrane distillation

    DEFF Research Database (Denmark)

    Fjerbæk Søtoft, Lene; Christensen, Knud Villy; Horn, Vibeke G

    2009-01-01

    melanocarpa is among the red fruits with the highest content of antioxidants [2] and has gained must interest due to the content of phenolic acids, procyanidins and polyphenolic compounds as anthocyanins [3]. In this study, osmotic membrane distillation (OMD) has been tested for the concentration of not only...... sugars, but in particular potentially bioactive components such as phenolic acids and flavonoids. OMD is carried out on 37 kg aronia juice at 30°C and the juice is concentrated from 12 wt% to 74 wt% dry matter. The juice is filtered to remove kernels, peel residues etc before concentration by OMD...

  4. Improving Liquid Entry Pressure of Polyvinylidene Fluoride (PVDF Membranes by Exploiting the Role of Fabrication Parameters in Vapor-Induced Phase Separation VIPS and Non-Solvent-Induced Phase Separation (NIPS Processes

    Directory of Open Access Journals (Sweden)

    Faisal Abdulla AlMarzooqi

    2017-02-01

    Full Text Available Polyvinylidene fluoride (PVDF is a popular polymer material for making membranes for several applications, including membrane distillation (MD, via the phase inversion process. Non-solvent-induced phase separation (NIPS and vapor-induced phase separation (VIPS are applied to achieve a porous PVDF membrane with low mass-transfer resistance and high contact angle (hydrophobicity. In this work, firstly, the impacts of several preparation parameters on membrane properties using VIPS and NIPS were studied. Then, the performance of the selected membrane was assessed in a lab-scale direct-contact MD (DCMD unit. The parametric study shows that decreasing PVDF concentration while increasing both relative humidity (RH and exposure time increased the contact angle and bubble-point pore size (BP. Those trends were investigated further by varying the casting thickness. At higher casting thicknesses and longer exposure time (up to 7.5 min, contact angle (CA increased but BP significantly decreased. The latter showed a dominant trend leading to liquid entry pressure (LEP increase with thickness.

  5. Biocatalytic degradation of pharmaceuticals, personal care products, industrial chemicals, steroid hormones and pesticides in a membrane distillation-enzymatic bioreactor.

    Science.gov (United States)

    Asif, Muhammad B; Hai, Faisal I; Kang, Jinguo; van de Merwe, Jason P; Leusch, Frederic D L; Price, William E; Nghiem, Long D

    2018-01-01

    Laccase-catalyzed degradation of a broad spectrum of trace organic contaminants (TrOCs) by a membrane distillation (MD)-enzymatic membrane bioreactor (EMBR) was investigated. The MD component effectively retained TrOCs (94-99%) in the EMBR, facilitating their continuous biocatalytic degradation. Notably, the extent of TrOC degradation was strongly influenced by their molecular properties. A significant degradation (above 90%) of TrOCs containing strong electron donating functional groups (e.g., hydroxyl and amine groups) was achieved, while a moderate removal was observed for TrOCs containing electron withdrawing functional groups (e.g., amide and halogen groups). Separate addition of two redox-mediators, namely syringaldehyde and violuric acid, further improved TrOC degradation by laccase. However, a mixture of both showed a reduced performance for a few pharmaceuticals such as primidone, carbamazepine and ibuprofen. Mediator addition increased the toxicity of the media in the enzymatic bioreactor, but the membrane permeate (i.e., final effluent) was non-toxic, suggesting an added advantage of coupling MD with EMBR. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Submerged membrane distillation for desalination of water

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem

    2016-01-01

    Submerged membrane modules for use for desalination of water are disclosed. In one or more aspects, the membrane modules can be submerged either in a feed solution tank or the feed solution can pass through the lumen side of the membrane submerged within the tank. The feed solution can be a water-based feed stream containing an amount of salt.

  7. Submerged membrane distillation for desalination of water

    KAUST Repository

    Francis, Lijo

    2016-10-27

    Submerged membrane modules for use for desalination of water are disclosed. In one or more aspects, the membrane modules can be submerged either in a feed solution tank or the feed solution can pass through the lumen side of the membrane submerged within the tank. The feed solution can be a water-based feed stream containing an amount of salt.

  8. Effect of Biological Contact Filters (BCFs on Membrane Fouling in Drinking Water Treatment Systems

    Directory of Open Access Journals (Sweden)

    Susumu Hasegawa

    2017-12-01

    Full Text Available Membrane fouling is a serious problem in drinking water treatment systems. Biological contact filters (BCFs are often used as a pretreatment to remove ammonia, dissolved organic matter (DOM, and metal ions such as iron and manganese. In this study, the effect of BCF as a pretreatment for membrane fouling was evaluated using a laboratory-scale mini module consisting of a mini BCF column and a mini MF column. Initially, it was confirmed that the main foulant was a biopolymer (at low concentration in the raw water. Subsequently, the biopolymer concentrations in the BCF influent and effluent were measured with the excitation emission matrix (EEM fluorescence spectroscopy and the liquid chromatograph organic carbon detector (LC-OCD. The fouling potential of the BCF influent and effluent was also measured to evaluate MF membrane fouling rate. The results demonstrate that application of the BCF reduced the biopolymer concentration of the effluent and reduced membrane fouling. The effect of BCF was also established in an actual drinking water treatment plant. It was found that optimizing the contact time of raw water with the BCF was crucial to reduce membrane fouling.

  9. 76 FR 71309 - Notice of Intent To Suspend the Distillers Co-Products Survey and All Associated Reports

    Science.gov (United States)

    2011-11-17

    ... Distillers Co-Products Survey and All Associated Reports AGENCY: National Agricultural Statistics Service... Distillers Co- Products survey currently approved under docket 0535-0247. FOR FURTHER INFORMATION CONTACT... . SUPPLEMENTARY INFORMATION: Title: Suspension of Distillers Co-Products Survey. OMB Control Number: 0535-0247...

  10. Morphology modification of polyethersulfone membrane from montmorillonite clay presence; Modificacao da morfologia de membrana de polietersulfona a partir da presenca de argila montmorilonita

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, R.S.B.; Oliveira, S.S.L.; Leite, A.M.D.; Araujo, E.M.; Lira, H.L., E-mail: edcleide.araujo@dema.ufcg.edu.br [Universidade Federal de Campina Grande (UAEMa/CCT/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Universidade Federal do Rio Grande do Norte (ECT/UFRN), Natal, RN (Brazil). Escola de Ciencias e Tecnologia

    2016-07-01

    The objective of this work is to produce hollow fiber membranes of polyethersulfone from the formation of hybrids with montmorillonite national clay (3 and 5% Brasgel PA), with the intention of modifying the morphology and improving the flow properties of the PES membrane. Initially, flat membranes were produced for characterization by X-ray diffraction (XRD) and contact angle. By XRD it was evident that membrane production and clay influenced the crystallinity of the polymer. The measurement of the contact angle indicated that the incorporation of clay promoted a change in membrane hydrophilicity, being more evident for with the 3% of MMT. By means of scanning electron microscopy (SEM) it was evidenced that the clay modified the morphology of the membrane, having a better distribution of the pores and the 'fingers'. The flow measurements showed that the membrane containing 3% of MMT had a higher permeability to distilled water, indicating its potential for the treatment of liquid effluents. (author)

  11. Osmotic distillation and quality evaluation of sucrose, apple and orange juices in hollow fiber membrane contactor

    Directory of Open Access Journals (Sweden)

    Rehman Waheed Ur

    2017-01-01

    Full Text Available Sucrose solution, apple and orange juices were concentrated through osmotic distillation (OD process using a mini-module Liqui-CelTM hollow fibre membrane contactor. Mass transport characteristics of water molecules from feed to stripping solution were studied. Process parameters such as feed temperature, feed flow rate and concentration of stripping solution (CaCl2 were varied. Sucrose solution was concentrated from 135 to 510 g TSS kg-1 in 340 min using feed-in- -lumen flow configuration at a start-up water flux of 0.250 L m-2 h-1 and a temperature of 30°C. Similarly, it was concentrated up to 510 g TSS kg-1 in 200 min using feed-in-shell flow configuration at a start-up water flux of 0.505 L m-2 hr1 and a temperature of 30°C. In a total recycle time of 340 min, clarified apple and orange juices were concentrated up to 500 g TSS kg-1 using feed-in-lumen flow configuration at a start-up water flux of 0.204 and 0.294 L m-2 hr1, respectively. It was found that quality parameters of fruit juices were well improved after the osmotic distillation process. The process therefore has good potential for application in the fruit processing industry for concentration of fruit juices.

  12. Propagation-of-uncertainty from contact angle and streaming potential measurements to XDLVO model assessments of membrane-colloid interactions.

    Science.gov (United States)

    Muthu, Satish; Childress, Amy; Brant, Jonathan

    2014-08-15

    Membrane fouling assessed from a fundamental standpoint within the context of the Derjaguin-Landau-Verwey-Overbeek (DLVO) model. The DLVO model requires that the properties of the membrane and foulant(s) be quantified. Membrane surface charge (zeta potential) and free energy values are characterized using streaming potential and contact angle measurements, respectively. Comparing theoretical assessments for membrane-colloid interactions between research groups requires that the variability of the measured inputs be established. The impact that such variability in input values on the outcome from interfacial models must be quantified to determine an acceptable variance in inputs. An interlaboratory study was conducted to quantify the variability in streaming potential and contact angle measurements when using standard protocols. The propagation of uncertainty from these errors was evaluated in terms of their impact on the quantitative and qualitative conclusions on extended DLVO (XDLVO) calculated interaction terms. The error introduced into XDLVO calculated values was of the same magnitude as the calculated free energy values at contact and at any given separation distance. For two independent laboratories to draw similar quantitative conclusions regarding membrane-foulant interfacial interactions the standard error in contact angle values must be⩽2.5°, while that for the zeta potential values must be⩽7 mV. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. The Effect of Scala Tympani Morphology on Basilar Membrane Contact With a Straight Electrode Array: A Human Temporal Bone Study.

    Science.gov (United States)

    Verberne, Juul; Risi, Frank; Campbell, Luke; Chambers, Scott; O'Leary, Stephen

    2017-01-01

    Scala tympani morphology influences the insertion dynamics and intra-scalar position of straight electrode arrays. Hearing preservation is the goal of cochlear implantation with current thin straight electrode arrays. These hug the lateral wall, facilitating full, atraumatic insertions. However, most studies still report some postoperative hearing loss. This study explores the influence of scala tympani morphology on array position relative to the basilar membrane and its possible contribution to postoperative hearing loss. Twenty-six fresh-frozen human temporal bones implanted with a straight electrode array were three-dimensionally reconstructed from micro-photographic histological sections. Insertion depth and the proximity between the array and basilar membrane were recorded. Lateral wall shape was quantified as a curvature ratio. Insertion depths ranged from 233 to 470 degrees. The mean first point of contact between the array and basilar membrane was 185 degrees; arrays tended to remain in contact with the membrane after first contacting it. Eighty-nine and 93% of arrays that reached the upper basal (>240-360 degrees) and second (>360-720 degrees) turns respectively contacted the basilar membrane in these regions. Scalar wall curvature ratio decreased significantly (the wall became steeper) from the basal to second turns. This shift correlated with a reduced distance between the array and basilar membrane. Scala tympani morphology influences the insertion dynamics and intra-scalar position of a straight electrode array. In addition to gross trauma of cochlear structures, contact between the array and basilar membrane and how this impacts membrane function should be considered in hearing preservation cases.

  14. A hybrid liquid-phase precipitation (LPP) process in conjunction with membrane distillation (MD) for the treatment of the INEEL sodium-bearing liquid waste.

    Science.gov (United States)

    Bader, M S H

    2005-05-20

    A novel hybrid system combining liquid-phase precipitation (LPP) and membrane distillation (MD) is integrated for the treatment of the INEEL sodium-bearing liquid waste. The integrated system provides a "full separation" approach that consists of three main processing stages. The first stage is focused on the separation and recovery of nitric acid from the bulk of the waste stream using vacuum membrane distillation (VMD). In the second stage, polyvalent cations (mainly TRU elements and their fission products except cesium along with aluminum and other toxic metals) are separated from the bulk of monovalent anions and cations (dominantly sodium nitrate) by a front-end LPP. In the third stage, MD is used first to concentrate sodium nitrate to near saturation followed by a rear-end LPP to precipitate and separate sodium nitrate along with the remaining minor species from the bulk of the aqueous phase. The LPP-MD hybrid system uses a small amount of an additive and energy to carry out the treatment, addresses multiple critical species, extracts an economic value from some of waste species, generates minimal waste with suitable disposal paths, and offers rapid deployment. As such, the LPP-MD could be a valuable tool for multiple needs across the DOE complex where no effective or economic alternatives are available.

  15. Geothermal Thermoelectric Generation (G-TEG) with Integrated Temperature Driven Membrane Distillation and Novel Manganese Oxide for Lithium Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Renew, Jay [Southern Research Inst., Birmingham, AL (United States); Hansen, Tim [Southern Research Inst., Birmingham, AL (United States)

    2017-06-01

    Southern Research Institute (Southern) teamed with partners Novus Energy Technologies (Novus), Carus Corporation (Carus), and Applied Membrane Technology, Inc. (AMT) to develop an innovative Geothermal ThermoElectric Generation (G-TEG) system specially designed to both generate electricity and extract high-value lithium (Li) from low-temperature geothermal brines. The process combined five modular technologies including – silica removal, nanofiltration (NF), membrane distillation (MD), Mn-oxide sorbent for Li recovery, and TEG. This project provides a proof of concept for each of these technologies. The first step in the process is silica precipitation through metal addition and pH adjustment to prevent downstream scaling in membrane processes. Next, the geothermal brine is concentrated with the first of a two stage MD system. The first stage MD system is made of a high-temperature material to withstand geothermal brine temperatures up to 150C.° The first stage MD is integrated with a G-TEG module for simultaneous energy generation. The release of energy from the MD permeate drives heat transfer across the TE module, producing electricity. The first stage MD concentrate is then treated utilizing an NF system to remove Ca2+ and Mg2+. The NF concentrate will be disposed in the well by reinjection. The NF permeate undergoes concentration in a second stage of MD (polymeric material) to further concentrate Li in the NF permeate and enhance the efficiency of the downstream Li recovery process utilizing a Mn-oxide sorbent. Permeate from both the stages of the MD can be beneficially utilized as the permeates will contain less contaminants than the feed water. The concentrated geothermal brines are then contacted with the Mn-oxide sorbent. After Li from the geothermal brine is adsorbed on the sorbent, HCl is then utilized to regenerate the sorbent and recover the Li. The research and development project showed that the Si removal goal (>80%) could

  16. Recovery of volatile fruit juice aroma compounds by membrane technology

    DEFF Research Database (Denmark)

    Bagger-Jørgensen, Rico; Meyer, Anne S.; Pinelo, Manuel

    2011-01-01

    The influence of temperature (10–45°C), feed flow rate (300–500L/h) and sweeping gas flow rate (1.2–2m3/h) on the recovery of berry fruit juice aroma compounds by sweeping gas membrane distillation (SGMD) was examined on an aroma model solution and on black currant juice in a lab scale membrane...... distillation set up. The data were compared to recovery of the aroma compounds by vacuum membrane distillation (VMD). The flux of SGMD increased with an increase in temperature, feed flow rate or sweeping gas flow rate. Increased temperature and feed flow rate also increased the concentration factors...... the degradation of anthocyanins and polyphenolic compounds in the juice. Industrial relevanceHigh temperature evaporation is the most widely used industrial technique for aroma recovery and concentration of juices, but membrane distillation (MD) may provide for gentler aroma stripping and lower energy consumption...

  17. ER-plasma membrane contact sites contribute to autophagosome biogenesis by regulation of local PI3P synthesis.

    Science.gov (United States)

    Nascimbeni, Anna Chiara; Giordano, Francesca; Dupont, Nicolas; Grasso, Daniel; Vaccaro, Maria I; Codogno, Patrice; Morel, Etienne

    2017-07-14

    The double-membrane-bound autophagosome is formed by the closure of a structure called the phagophore, origin of which is still unclear. The endoplasmic reticulum (ER) is clearly implicated in autophagosome biogenesis due to the presence of the omegasome subdomain positive for DFCP1, a phosphatidyl-inositol-3-phosphate (PI3P) binding protein. Contribution of other membrane sources, like the plasma membrane (PM), is still difficult to integrate in a global picture. Here we show that ER-plasma membrane contact sites are mobilized for autophagosome biogenesis, by direct implication of the tethering extended synaptotagmins (E-Syts) proteins. Imaging data revealed that early autophagic markers are recruited to E-Syt-containing domains during autophagy and that inhibition of E-Syts expression leads to a reduction in autophagosome biogenesis. Furthermore, we demonstrate that E-Syts are essential for autophagy-associated PI3P synthesis at the cortical ER membrane via the recruitment of VMP1, the stabilizing ER partner of the PI3KC3 complex. These results highlight the contribution of ER-plasma membrane tethers to autophagosome biogenesis regulation and support the importance of membrane contact sites in autophagy. © 2017 The Authors.

  18. Distill: a suite of web servers for the prediction of one-, two- and three-dimensional structural features of proteins

    Directory of Open Access Journals (Sweden)

    Walsh Ian

    2006-09-01

    Full Text Available Abstract Background We describe Distill, a suite of servers for the prediction of protein structural features: secondary structure; relative solvent accessibility; contact density; backbone structural motifs; residue contact maps at 6, 8 and 12 Angstrom; coarse protein topology. The servers are based on large-scale ensembles of recursive neural networks and trained on large, up-to-date, non-redundant subsets of the Protein Data Bank. Together with structural feature predictions, Distill includes a server for prediction of Cα traces for short proteins (up to 200 amino acids. Results The servers are state-of-the-art, with secondary structure predicted correctly for nearly 80% of residues (currently the top performance on EVA, 2-class solvent accessibility nearly 80% correct, and contact maps exceeding 50% precision on the top non-diagonal contacts. A preliminary implementation of the predictor of protein Cα traces featured among the top 20 Novel Fold predictors at the last CASP6 experiment as group Distill (ID 0348. The majority of the servers, including the Cα trace predictor, now take into account homology information from the PDB, when available, resulting in greatly improved reliability. Conclusion All predictions are freely available through a simple joint web interface and the results are returned by email. In a single submission the user can send protein sequences for a total of up to 32k residues to all or a selection of the servers. Distill is accessible at the address: http://distill.ucd.ie/distill/.

  19. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Mitting, E K

    1882-08-09

    The broken-up shale is placed in cast-iron retorts, heated externally, having exit tubes placed at a low level. Each retort is provided with a steam-pipe with a regulating-cock outside, the pipe being carried around the walls of the retort in a spiral or zig-zag way to ensure superheating of the steam, perforations being made in the pipe to allow exit for the steam into the retort. The steam, which may if desired be superheated before entrance, is passed into the retort when the latter has attained a temperature of from 210 to 250/sup 0/C and the passage is continued while the temperature rises, as long as distillation goes on. The exit pipe to the retort leads to a condenser of much condensing-surface, provided with a drag obtained by an exhausting steam jet or otherwise. The distilled products consist of tar, oils, wax, ammoniacal water (stated to be in greater proportion through the use of the process), and lighting and heating gas. The latter gas goes through a scrubber to a gasholder. The carbonaceous residue in the retort is discharged when cooled below a red heat, into sheet-iron cylinders, with tightly fitting lids, to avoid as far as possible contact with the atmosphere.

  20. Flexible anodized aluminum oxide membranes with customizable back contact materials.

    Science.gov (United States)

    Nadimpally, B; Jarro, C A; Mangu, R; Rajaputra, S; Singh, V P

    2016-12-16

    Anodized aluminum oxide (AAO) membranes were fabricated using flexible substrate/carrier material. This method facilitates the use of AAO templates with many different materials as substrates that are otherwise incompatible with most anodization techniques. Thin titanium (Ti) and tungsten (W) layers were employed as interlayer materials. Titanium enhances adhesion. Tungsten not only helps eliminate the barrier layer but also plays a critical role in enabling the use of flexible substrates. The resulting flexible templates provide new, exciting opportunities in photovoltaic and other device applications. CuInSe 2 nanowires were electrochemically deposited into porous AAO templates with molybdenum (Mo) as the back contact material. The feasibility of using any material to form a contact with semiconductor nanowires has been demonstrated for the first time enabling new avenues in photovoltaic applications.

  1. Flexible anodized aluminum oxide membranes with customizable back contact materials

    Science.gov (United States)

    Nadimpally, B.; Jarro, C. A.; Mangu, R.; Rajaputra, S.; Singh, V. P.

    2016-12-01

    Anodized aluminum oxide (AAO) membranes were fabricated using flexible substrate/carrier material. This method facilitates the use of AAO templates with many different materials as substrates that are otherwise incompatible with most anodization techniques. Thin titanium (Ti) and tungsten (W) layers were employed as interlayer materials. Titanium enhances adhesion. Tungsten not only helps eliminate the barrier layer but also plays a critical role in enabling the use of flexible substrates. The resulting flexible templates provide new, exciting opportunities in photovoltaic and other device applications. CuInSe2 nanowires were electrochemically deposited into porous AAO templates with molybdenum (Mo) as the back contact material. The feasibility of using any material to form a contact with semiconductor nanowires has been demonstrated for the first time enabling new avenues in photovoltaic applications.

  2. Structural basis of sterol recognition and nonvesicular transport by lipid transfer proteins anchored at membrane contact sites.

    Science.gov (United States)

    Tong, Junsen; Manik, Mohammad Kawsar; Im, Young Jun

    2018-01-30

    Membrane contact sites (MCSs) in eukaryotic cells are hotspots for lipid exchange, which is essential for many biological functions, including regulation of membrane properties and protein trafficking. Lipid transfer proteins anchored at membrane contact sites (LAMs) contain sterol-specific lipid transfer domains [StARkin domain (SD)] and multiple targeting modules to specific membrane organelles. Elucidating the structural mechanisms of targeting and ligand recognition by LAMs is important for understanding the interorganelle communication and exchange at MCSs. Here, we determined the crystal structures of the yeast Lam6 pleckstrin homology (PH)-like domain and the SDs of Lam2 and Lam4 in the apo form and in complex with ergosterol. The Lam6 PH-like domain displays a unique PH domain fold with a conserved N-terminal α-helix. The Lam6 PH-like domain lacks the basic surface for phosphoinositide binding, but contains hydrophobic patches on its surface, which are critical for targeting to endoplasmic reticulum (ER)-mitochondrial contacts. Structures of the LAM SDs display a helix-grip fold with a hydrophobic cavity and a flexible Ω1-loop as a lid. Ergosterol is bound to the pocket in a head-down orientation, with its hydrophobic acyl group located in the tunnel entrance. The Ω1-loop in an open conformation is essential for ergosterol binding by direct hydrophobic interaction. Structural comparison suggested that the sterol binding mode of the Lam2 SD2 is likely conserved among the sterol transfer proteins of the StARkin superfamily. Structural models of full-length Lam2 correlated with the sterol transport function at the membrane contact sites.

  3. Toxicity of petroleum hydrocarbon distillates to soil organisms.

    Science.gov (United States)

    Cermak, Janet H; Stephenson, Gladys L; Birkholz, Detlef; Wang, Zhendi; Dixon, D George

    2010-12-01

    Canadian standards for petroleum hydrocarbons in soil are based on four distillate ranges (F1, C6-C10; F2, >C10-C16; F3, >C16-C34; and F4, >C34). Concerns have arisen that the ecological soil contact standards for F3 may be overly conservative. Oil distillates were prepared and characterized, and the toxicity of F3 and two subfractions, F3a (>C16-C23) and F3b (>C23-C34), to earthworms (Eisenia andrei), springtails (Orthonychiurus folsomi), and northern wheatgrass (Elymus lanceolatus), as well as the toxicity of F2 to earthworms, was determined. Clean soil was spiked with individual distillates and measured concentrations were determined for select tests. Results agree with previous studies with these distillates. Reported toxicities of crude and petroleum products to invertebrates were generally comparable to that of F3 and F3a. The decreasing order of toxicity was F3a > F3 > F3b with invertebrates, and F3a > F3b > F3 with plants. The toxicities of F3a and F3b were not sufficiently different to recommend regulating hydrocarbons based on these distillate ranges. The results also suggest that test durations may be insufficient for determining toxicity of higher distillate ranges, and that the selection of species and endpoints may significantly affect interpretation of toxicity test results. Copyright © 2010 SETAC.

  4. Thermal distillation system utilizing biomass energy burned in stove by means of heat pipe

    Directory of Open Access Journals (Sweden)

    Hiroshi Tanaka

    2016-09-01

    Full Text Available A thermal distillation system utilizing a part of the thermal energy of biomass burned in a stove during cooking is proposed. The thermal energy is transported from the stove to the distiller by means of a heat pipe. The distiller is a vertical multiple-effect diffusion distiller, in which a number of parallel partitions in contact with saline-soaked wicks are set vertically with narrow gaps of air. A pilot experimental apparatus was constructed and tested with a single-effect and multiple-effect distillers to investigate primarily whether a heat pipe can transport thermal energy adequately from the stove to the distiller. It was found that the temperatures of the heated plate and the first partition of the distiller reached to about 100 °C and 90 °C, respectively, at steady state, showing that the heat pipe works sufficiently. The distilled water obtained was about 0.75 and 1.35 kg during the first 2 h of burning from a single-effect and multiple-effect distillers, respectively.

  5. CONTACT ANGLE OF YUCCA MOUNTAIN WELDED TUFF WITH WATER AND BRINES

    International Nuclear Information System (INIS)

    H. Kalia

    2006-01-01

    A number of tests were performed to acquire contact angles between Yucca Mountain welded tuff from Topopah Springs Lower Lithophysal geologic unit and various brine solutions. The tests were performed on core disks received from Sample Management Facility (SMF), oven dried to a constant weight and the core disks vacuum saturated in: distilled water, J-13 water, calcium chloride brine and sodium chloride brine to constant weight. The contact angles were acquired from eight points on the surface of the core disks, four on rough surface, and four on polished surface. The contact angle was measured by placing a droplet of the test fluid, distilled water, J-13 water, calcium chloride brine and sodium chloride brine on the core disks. The objective of this test was to acquire contact angles as a potential input to estimating capillary forces in accumulated dust on the waste packages and drip shields slated for the proposed High-Level Radioactive Waste Repository at Yucca Mountain, Nevada. It was noted that once the droplet contacts the test surface, it continues to spread hence the contact angle continues to decrease with elapsed time. The maximum observed angle was at time 0 or when the drop contacted the rock surface. The measured contact angle, in all cases has significant scatter. In general, the time zero contact angles for core disks saturated in sodium chloride brine were smaller than those saturated in calcium chloride brine, distilled water, and J-13 water. The contact angles for samples saturated in distilled water, J-13 water and calcium chloride brine at time zero were similar. There was slight difference between the observed contact angles for smooth and rough surface of the test samples. The contact angles for smooth surfaces were smaller than for the rough surfaces

  6. Polyethersulfone/clay membranes and its water permeability

    International Nuclear Information System (INIS)

    Cavalho, Thamyres Cardoso de; Medeiros, Vanessa da Nobrega; Araujo, Edcleide Maria de; Lira, Helio Lucena; Leite, Amanda Melissa Damiao

    2017-01-01

    Membranes can be considered polymeric or inorganic films that function as a semipermeable barrier to filtration on a molecular scale, separating two phases and restricting, totally or partially, the transportation of one or more chemical species (solute) present in the solution. Therefore, the aim of this work is to produce polyethersulfone membranes (PES) and polyethersulfone/clay by phase inversion technique and evaluate the presence of clay in obtaining membranes for wastewater treatment. The used solvent was dimethylformamide (DMF) and clays were Brasgel PA (MMT) and Cloisite Na (CL Na) in the proportion of 3 to 5% (wt.). By Xray diffraction (XRD), the membranes with 3% of MMT and CL Na clays apparently had partially exfoliated structures. For the composition with 5% of CL Na a small peak was observed, which indicates that this is possibly an intercalated structure or microcomposite. By scanning electron microscopy (SEM), visualizes that the pure surface of the pure PES membrane a structure apparently without pores was observed in the used magnification and without roughness surface when compared to membranes with clay. The measurements of contact angle indicated that the inclusion of clay altered the wetting ability of the membranes. The flow with distilled water for all membranes started high and over time reached a stabilization level. Thus, it can be concluded that the presence and the content of clay altered the morphology of the membrane, contributing to an increase in water flow. (author)

  7. Influence of high range of mass transfer coefficient and convection heat transfer on direct contact membrane distillation performance

    KAUST Repository

    Lee, Jung Gil; Jeong, Sanghyun; Alsaadi, Ahmad Salem; Ghaffour, NorEddine

    2017-01-01

    (>2.1×10−6kg/m2sPa: membranes under development) were simulated using an experimentally validated model at different ranges of convection heat transfer by varying the inlet flow rates and spacer enhancement factor. The effect of mass transfer

  8. Hybrid Pressure Retarded Osmosis−Membrane Distillation (PRO−MD) Process for Osmotic Power and Clean Water Generation

    KAUST Repository

    Han, Gang

    2015-05-20

    A novel pressure retarded osmosis−membrane distillation (PRO−MD) hybrid process has been experimentally conceived for sustainable production of renewable osmotic power and clean water from various waters. The proposed PRO−MD system may possess unique advantages of high water recovery rate, huge osmotic power generation, well controlled membrane fouling, and minimal environmental impacts. Experimental results show that the PRO−MD hybrid process is promising that not only can harvest osmotic energy from freshwater but also from wastewater. When employing a 2 M NaCl MD concentrate as the draw solution, ultrahigh power densities of 31.0 W/m2 and 9.3 W/m2 have been demonstrated by the PRO subsystem using deionized water and real wastewater brine as the feeds, respectively. Simultaneously, high purity potable water with a flux of 32.5−63.1 L/(m2.h) can be produced by the MD subsystem at 40−60 °C without any detrimental effects of fouling. The energy consumption in the MD subsystem might be further reduced by applying a heat exchanger in the hybrid system and using low-grade heat or solar energy to heat up the feed solution. The newly developed PRO−MD hybrid process would provide insightful guidelines for the exploration of alternative green technologies for renewable osmotic energy and clean water production.

  9. Distillation methods

    International Nuclear Information System (INIS)

    Konecny, C.

    1975-01-01

    Two main methods of separation using the distillation method are given and evaluated, namely evaporation and distillation in carrier gas flow. Two basic apparatus are described for illustrating the methods used. The use of the distillation method in radiochemistry is documented by a number of examples of the separation of elements in elemental state, volatile halogenides and oxides. Tables give a survey of distillation methods used for the separation of the individual elements and give conditions under which this separation takes place. The suitability of the use of distillation methods in radiochemistry is discussed with regard to other separation methods. (L.K.)

  10. Purification Simulation With Vapor Permeation and Distillation-Adsorption In Bioethanol Plant

    Directory of Open Access Journals (Sweden)

    Misri Gozan

    2017-04-01

    Full Text Available High purity of Bioethanol is required in biofuel mixing with gasoline (EXX. In bioethanol production line, the azeotropic property of ethanol-water becomes the barrier for purification process. This study examined two bioethanol separation processes by support of simulation tools, Superpro Designer 9.0 software. Ethanol purity and a low costeconomical process were the major considerations. Purification method of vapor permeation membrane technology was compared with distillation-adsorption method. Data from previous lab experiments and some literatures were used. The results showed that distillation-adsorption method is more economical compared to vapor permeation technology. Payback period of the simulation is 3.9 years and 4.3 years to distillation adsorption and vapor permeation respectively with each IRR value is 20.23% and 17.89%. Initial investment value of vapor permeation is 9.6% higher than distillation method. Significant difference observed in operating costs, since more units involved in vapor permeation require more labors to operate.

  11. Distilling hydrocarbon oils

    Energy Technology Data Exchange (ETDEWEB)

    Tausz, J

    1924-07-16

    Hydrocarbon oils such as petroleum, shale oils, lignite or coal tar oils are purified by distilling them and collecting the distillate in fractions within narrow limits so that all the impurities are contained in one or more of the narrow fractions. In distilling ligroin obtained by destructive distillation of brown coal, it is found that the coloring and resin-forming constituents are contained in the fractions distilling over at 62 to 86/sup 0/C and 108/sup 0/C. The ligroin is purified, therefore, by distillating in an apparatus provided with an efficient dephlegmotor and removing these two fractions. The distillation may be carried out wholly or in part under reduced pressure, and fractions separated under ordinary pressure may be subsequently distilled under reduced pressure. The hydrocarbons may be first separated into fractions over wider limits and the separate fractions be subjected to a further fractional distillation.

  12. Utilization of membranes for H2O recycle system

    Science.gov (United States)

    Ohya, H.; Oguchi, M.

    1986-01-01

    Conceptual studies of closed ecological life support systems (CELSS) carried out at NAL in Japan for a water recycle system using membranes are reviewed. The system will treat water from shower room, urine, impure condensation from gas recycle system, and so on. The H2O recycle system is composed of prefilter, ultrafiltration membrane, reverse osmosis membrane, and distillator. Some results are shown for a bullet train of toilet-flushing water recycle equipment with an ultraviltration membrane module. The constant value of the permeation rate with a 4.7 square meters of module is about 70 1/h after 500th of operation. Thermovaporization with porous polytetrafluorocarbon membrane is also proposed to replce the distillator.

  13. Contact behavior modelling and its size effect on proton exchange membrane fuel cell

    Science.gov (United States)

    Qiu, Diankai; Peng, Linfa; Yi, Peiyun; Lai, Xinmin; Janßen, Holger; Lehnert, Werner

    2017-10-01

    Contact behavior between the gas diffusion layer (GDL) and bipolar plate (BPP) is of significant importance for proton exchange membrane fuel cells. Most current studies on contact behavior utilize experiments and finite element modelling and focus on fuel cells with graphite BPPs, which lead to high costs and huge computational requirements. The objective of this work is to build a more effective analytical method for contact behavior in fuel cells and investigate the size effect resulting from configuration alteration of channel and rib (channel/rib). Firstly, a mathematical description of channel/rib geometry is outlined in accordance with the fabrication of metallic BPP. Based on the interface deformation characteristic and Winkler surface model, contact pressure between BPP and GDL is then calculated to predict contact resistance and GDL porosity as evaluative parameters of contact behavior. Then, experiments on BPP fabrication and contact resistance measurement are conducted to validate the model. The measured results demonstrate an obvious dependence on channel/rib size. Feasibility of the model used in graphite fuel cells is also discussed. Finally, size factor is proposed for evaluating the rule of size effect. Significant increase occurs in contact resistance and porosity for higher size factor, in which channel/rib width decrease.

  14. Amniotic membrane welded to contact lens by 1470-nm diode laser:a novel method for sutureless amniotic membrane transplantation

    Directory of Open Access Journals (Sweden)

    Rifat Rasier

    2014-12-01

    Full Text Available AIM: To avoid the side effects of the suture usage by welding amniotic membrane (AM to contact lens (CL with laser.METHODS:AM was taken from pregnant women and cleaned from blood clots with sterile phosphate-buffered physiological saline solution which included antibiotics. Stromal side of the AM was spread inside of the CL and it was welded to CL by 1470 nm diode laser. 600 μm diameter fiber tip of the laser was contacted with the epithelial side of the AM from 4 separate points. After welding excess amniotic membrane around the CL was cut with a scalpel.RESULTS:Stromal side of the AM was spread inside of the CL and then with laser fiber, different power levels and exposure times were applied on the epithelium of AM and 340 mW for seven seconds was found optimal. CL and AM attached with the spot welding effect in 4 points by touching fiber tip. CL-AM welded complex did not separated from each other while holding AM that extend beyond the CL with the help of two forceps.CONCLUSION:As a conclusion, it was aimed in this study to achieve the success of the conventional amniotic membrane transplantation (AMTwith the easiness of applying a CL and to avoid risks and side effects of corneal or conjunctival suturing. The results showed that the application of the CL–AM complex will be as easy as the application of a CL and lasts shortly.

  15. Dry distillation

    Energy Technology Data Exchange (ETDEWEB)

    1939-11-30

    To heat rapidly, and prevent agglutination of carbonaceous material duriing distillation of shale, a furnace of the tunnel type has four compartments (the preheating chamber, the distillation chamber proper, and two cooling chambers). Waggons, which convey the material through the distilling chamber, have perforated bottoms. Above the waggons in the distilling chamber are three heating sections having pipes which pass through the sections and communicate with the distilling chamber. Fans cause the distillation gases to circulate through the material and the pipes. The heating gases from three fire boxes are introduced into the oven, and circulate around pipes and are drawn to the discharge apertures by the fans. The heating gases introduced at two points travel in the direction of the material being treated, while the gases introduced at a third point travel in counter flow thereto. Gas is discharged by two pipes. Trucks carrying treated material are passed to two cooling chambers.

  16. Membrane methods for the treatment of low and intermediate radioactive wastes

    International Nuclear Information System (INIS)

    Zakrzewska-Trznadel, G.; Chmielewski, A.G.; Harasimowicz, M.; Tyminski, B.

    2001-01-01

    Membrane processes have been investigated at Institute of Nuclear Chemistry and Technology, Warsaw (INCT) since eighties. Different polymeric membranes were tested with radioactive solutions in long time operations. Such membrane processes as ultrafiltration, 'seeded' ultrafiltration and reverse osmosis were studied in a laboratory scale and in pilot plant experiments. The experiments show the advantage of membrane methods over some other processes used for radioactive wastes treatment. The RO method is being implemented at Institute of Atomic Energy in Swierk (Warsaw), where liquid radioactive wastes from all of Poland are collected and processed. Another method for liquid radioactive wastes treatment employing hydrophobic polymer membrane was developed at INCT. The process called membrane distillation was investigated for some years and the pilot plant for the processing 50 dm 3 /h of radioactive effluents was constructed. The pilot plant experiments show membrane distillation allows complete purification of liquid radioactive waste in one stage and does not need additional processes to ensure sufficient purity of water discharged to the environment. Comparison between two processes: membrane distillation and reverse osmosis showed that in some cases MD could be more beneficial. (author)

  17. Non-thermal Production of Natural betalain Colorant Concentrate from Red Beet Extract by Using the Osmotic Distillation

    Directory of Open Access Journals (Sweden)

    Nazanin Amirasgari

    2016-04-01

    Full Text Available Background and Objectives: Red beet extract concentrate can be used as a natural colorant in food products; however, destructive effects of thermal methods to produce juice concentrate decrease nutritional value in the final product. Materials and Methods: In this study, red beet extract was concentrated using osmotic distillation method, and the best pretreatment was evaluated to increase the efficiency of the concentration process. Also changes in some physicochemical properties such as betacyanins and betaxanthins contents, total phenolic compounds and antioxidant activity of red beet juice were evaluated by both the membrane and thermal concentration methods. Results: The results showed that the best concentration efficiency was obtained after pretreatment of the fresh juice with centrifugation at 1699 G for 17 min. Evaluation of the effect of both the membrane and thermal concentration processes on the physicochemical properties of juice showed that the membrane method did not change betacyanin and betaxanthin contents, total phenolic compounds, and antioxidant activity of the red beet extract. However, these properties decreased with the thermal concentration method by 26, 15, 11 and 13%, respectively. Conclusions: According to the results, osmotic distillation can produce red beet concentrate with more nutritional value than the concentrate produced with thermal method. Keywords: Membrane, Natural betalain colorant, Osmotic distillation, Red beet

  18. Staying Tight: Plasmodesmal Membrane Contact Sites and the Control of Cell-to-Cell Connectivity in Plants.

    Science.gov (United States)

    Tilsner, Jens; Nicolas, William; Rosado, Abel; Bayer, Emmanuelle M

    2016-04-29

    Multicellularity differs in plants and animals in that the cytoplasm, plasma membrane, and endomembrane of plants are connected between cells through plasmodesmal pores. Plasmodesmata (PDs) are essential for plant life and serve as conduits for the transport of proteins, small RNAs, hormones, and metabolites during developmental and defense signaling. They are also the only pathways available for viruses to spread within plant hosts. The membrane organization of PDs is unique, characterized by the close apposition of the endoplasmic reticulum and the plasma membrane and spoke-like filamentous structures linking the two membranes, which define PDs as membrane contact sites (MCSs). This specialized membrane arrangement is likely critical for PD function. Here, we review how PDs govern developmental and defensive signaling in plants, compare them with other types of MCSs, and discuss in detail the potential functional significance of the MCS nature of PDs.

  19. Hybrid pressure retarded osmosis-membrane distillation system for power generation from low-grade heat: thermodynamic analysis and energy efficiency.

    Science.gov (United States)

    Lin, Shihong; Yip, Ngai Yin; Cath, Tzahi Y; Osuji, Chinedum O; Elimelech, Menachem

    2014-05-06

    We present a novel hybrid membrane system that operates as a heat engine capable of utilizing low-grade thermal energy, which is not readily recoverable with existing technologies. The closed-loop system combines membrane distillation (MD), which generates concentrated and pure water streams by thermal separation, and pressure retarded osmosis (PRO), which converts the energy of mixing to electricity by a hydro-turbine. The PRO-MD system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages for heat source temperatures ranging from 40 to 80 °C and working concentrations of 1.0, 2.0, and 4.0 mol/kg NaCl. The factors controlling the energy efficiency of the heat engine were evaluated for both limited and unlimited mass and heat transfer kinetics in the thermal separation stage. In both cases, the relative flow rate between the MD permeate (distillate) and feed streams is identified as an important operation parameter. There is an optimal relative flow rate that maximizes the overall energy efficiency of the PRO-MD system for given working temperatures and concentration. In the case of unlimited mass and heat transfer kinetics, the energy efficiency of the system can be analytically determined based on thermodynamics. Our assessment indicates that the hybrid PRO-MD system can theoretically achieve an energy efficiency of 9.8% (81.6% of the Carnot efficiency) with hot and cold working temperatures of 60 and 20 °C, respectively, and a working solution of 1.0 M NaCl. When mass and heat transfer kinetics are limited, conditions that more closely represent actual operations, the practical energy efficiency will be lower than the theoretically achievable efficiency. In such practical operations, utilizing a higher working concentration will yield greater energy efficiency. Overall, our study demonstrates the theoretical viability of the PRO-MD system and identifies the key factors for performance

  20. Bulk and contact resistances of gas diffusion layers in proton exchange membrane fuel cells

    Science.gov (United States)

    Ye, Donghao; Gauthier, Eric; Benziger, Jay B.; Pan, Mu

    2014-06-01

    A multi-electrode probe is employed to distinguish the bulk and contact resistances of the catalyst layer (CL) and the gas diffusion layer (GDL) with the bipolar plate (BPP). Resistances are compared for Vulcan carbon catalyst layers (CL), carbon paper and carbon cloth GDL materials, and GDLs with microporous layers (MPL). The Vulcan carbon catalyst layer bulk resistance is 100 times greater than the bulk resistance of carbon paper GDL (Toray TG-H-120). Carbon cloth (CCWP) has bulk and contact resistances twice those of carbon paper. Compression of the GDL decreases the GDL contact resistance, but has little effect on the bulk resistance. Treatment of the GDL with polytetrafluoroethylene (PTFE) increases the contact resistance, but has little effect on the bulk resistance. A microporous layer (MPL) added to the GDL decreases the contact resistance, but has little effect on the bulk resistance. An equivalent circuit model shows that for channels less than 1 mm wide the contact resistance is the major source of electronic resistance and is about 10% of the total ohmic resistance associated with the membrane electrode assembly.

  1. Attainability and minimum energy of single-stage membrane and membrane/distillation hybrid processes

    KAUST Repository

    Alshehri, Ali; Lai, Zhiping

    2014-01-01

    As an energy-efficient separation method, membrane technology has attracted more and more attentions in many challenging separation processes. The attainability and the energy consumption of a membrane process are the two basic fundamental questions

  2. Distilling solid carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, H; Laing, B

    1926-12-04

    In a process of distilling solid carbonaceous materials with by-product recovery, the time factor and the temperature gradient during the distillation period are so controlled that a temperature difference exceeding 150/sup 0/C is avoided between the temperatures at the center and periphery of any suitable size of material or thickness of fuel bed. The material is heated by direct contact with an inert gas, such as water gas, producer gas, or combustion gases, which is passed in counterflow to the material and whose volume is such as to lower the vapor tension or partial pressure of the volatilizable oils and to withdraw the oils without cracking of the oil vapors. The material may be subjected to a preliminary heat treatment by gases containing 2 to 3 percent of free oxygen to reduce its coking properties, and free oxygen may be added either to the heating gases during the heat treatment, or to the retort and heating gases and vapors to polymerize resinous bodies prior to condensation or during condensation and while the oils are still wholly or partially in the vapor state.

  3. Multipartite nonlocality distillation

    International Nuclear Information System (INIS)

    Hsu, Li-Yi; Wu, Keng-Shuo

    2010-01-01

    The stronger nonlocality than that allowed in quantum theory can provide an advantage in information processing and computation. Since quantum entanglement is distillable, can nonlocality be distilled in the nonsignalling condition? The answer is positive in the bipartite case. In this article the distillability of the multipartite nonlocality is investigated. We propose a distillation protocol solely exploiting xor operations on output bits. The probability-distribution vectors and matrix are introduced to tackle the correlators. It is shown that only the correlators with extreme values can survive the distillation process. As the main result, the amplified nonlocality cannot maximally violate any Bell-type inequality. Accordingly, a distillability criterion in the postquantum region is proposed.

  4. Integration of membrane distillation into traditional salt farming method: Process development and modelling

    Science.gov (United States)

    Hizam, S.; Bilad, M. R.; Putra, Z. A.

    2017-10-01

    Farmers still practice the traditional salt farming in many regions, particularly in Indonesia. This archaic method not only produces low yield and poor salt quality, it is also laborious. Furthermore, the farming locations typically have poor access to fresh water and are far away from electricity grid, which restrict upgrade to a more advanced technology for salt production. This paper proposes a new concept of salt harvesting method that improves the salt yield and at the same time facilitates recovery of fresh water from seawater. The new concept integrates solar powered membrane distillation (MD) and photovoltaic cells to drive the pumping. We performed basic solar still experiments to quantify the heat flux received by a pond. The data were used as insight for designing the proposed concept, particularly on operational strategy and the most effective way to integrate MD. After the conceptual design had been developed, we formulated mass and energy balance to estimate the performance of the proposed concept. Based on our data and design, it is expected that the system would improve the yield and quality of the salt production, maximizing fresh water harvesting, and eventually provides economical gain for salt farmers hence improving their quality of life. The key performance can only be measured via experiment using gain output ratio as performance indicator, which will be done in a future study.

  5. Mitochondrial cardiolipin/phospholipid trafficking: the role of membrane contact site complexes and lipid transfer proteins.

    Science.gov (United States)

    Schlattner, Uwe; Tokarska-Schlattner, Malgorzata; Rousseau, Denis; Boissan, Mathieu; Mannella, Carmen; Epand, Richard; Lacombe, Marie-Lise

    2014-04-01

    Historically, cellular trafficking of lipids has received much less attention than protein trafficking, mostly because its biological importance was underestimated, involved sorting and translocation mechanisms were not known, and analytical tools were limiting. This has changed during the last decade, and we discuss here some progress made in respect to mitochondria and the trafficking of phospholipids, in particular cardiolipin. Different membrane contact site or junction complexes and putative lipid transfer proteins for intra- and intermembrane lipid translocation have been described, involving mitochondrial inner and outer membrane, and the adjacent membranes of the endoplasmic reticulum. An image emerges how cardiolipin precursors, remodeling intermediates, mature cardiolipin and its oxidation products could migrate between membranes, and how this trafficking is involved in cardiolipin biosynthesis and cell signaling events. Particular emphasis in this review is given to mitochondrial nucleoside diphosphate kinase D and mitochondrial creatine kinases, which emerge to have roles in both, membrane junction formation and lipid transfer. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Membrane Modeling, Simulation and Optimization for Propylene/Propane Separation

    KAUST Repository

    Alshehri, Ali

    2015-06-01

    Energy efficiency is critical for sustainable industrial growth and the reduction of environmental impacts. Energy consumption by the industrial sector accounts for more than half of the total global energy usage and, therefore, greater attention is focused on enhancing this sector’s energy efficiency. It is predicted that by 2020, more than 20% of today’s energy consumption can be avoided in countries that have effectively implemented an action plan towards efficient energy utilization. Breakthroughs in material synthesis of high selective membranes have enabled the technology to be more energy efficient. Hence, high selective membranes are increasingly replacing conventional energy intensive separation processes, such as distillation and adsorption units. Moreover, the technology offers more special features (which are essential for special applications) and its small footprint makes membrane technology suitable for platform operations (e.g., nitrogen enrichment for oil and gas offshore sites). In addition, its low maintenance characteristics allow the technology to be applied to remote operations. For these reasons, amongst other, the membrane technology market is forecast to reach $16 billion by 2017. This thesis is concerned with the engineering aspects of membrane technology and covers modeling, simulation and optimization of membranes as a stand-alone process or as a unit operation within a hybrid system. Incorporating the membrane model into a process modeling software simplifies the simulation and optimization of the different membrane processes and hybrid configurations, since all other unit operations are pre-configured. Various parametric analyses demonstrated that only the membrane selectivity and transmembrane pressure ratio parameters define a membrane’s ability to accomplish a certain separation task. Moreover, it was found that both membrane selectivity and pressure ratio exhibit a minimum value that is only defined by the feed composition

  7. Characterization of polyethersulfone-polyimide hollow fiber membranes by atomic force microscopy and contact angle goniometery

    NARCIS (Netherlands)

    Khulbe, K.C.; Feng, C.; Matsuura, T.; Kapantaidakis, G.; Wessling, Matthias; Koops, G.H.

    2003-01-01

    Asymmetric blend polyethersulfone-polyimide (PES-PI) hollow fiber membranes prepared at different air gap and used for gas separation are characterized by atomic force microscopy (inside and out side surfaces) and by measuring the contact angle of out side surface. The outer surface was entirely

  8. Efficient ethanol recovery from fermentation broths with integrated distillation-vapor permeation hybrid process

    Science.gov (United States)

    The energy demand of distillation-molecular sieve systems for ethanol recovery/dehydration can be significant, particularly for dilute solutions. An alternative hybrid process integrating vapor stripping (like a beer still) with vapor compression and a vapor permeation membrane s...

  9. Catalytic distillation structure

    Science.gov (United States)

    Smith, L.A. Jr.

    1984-04-17

    Catalytic distillation structure is described for use in reaction distillation columns, and provides reaction sites and distillation structure consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and is present with the catalyst component in an amount such that the catalytic distillation structure consists of at least 10 volume % open space. 10 figs.

  10. Distillation of hydrogen isotopes for polarized HD targets

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, T., E-mail: takeshi@rcnp.osaka-u.ac.jp [Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047 (Japan); Bouchigny, S. [IN2P3, Institut de Physique Nucleaire, F-91406 Orsay (France); CEA LIST, BP6-92265 Fontenay-aux-Roses, CEDEX (France); Didelez, J.-P. [IN2P3, Institut de Physique Nucleaire, F-91406 Orsay (France); Fujiwara, M. [Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047 (Japan); Fukuda, K. [Kansai University of Nursing and Health Sciences, Shizuki Awaji 656-2131 (Japan); Kohri, H.; Kunimatsu, T.; Morisaki, C.; Ono, S. [Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047 (Japan); Rouille, G. [IN2P3, Institut de Physique Nucleaire, F-91406 Orsay (France); Tanaka, M. [Kobe Tokiwa University, Ohtani-cho 2-6-2, Nagata, Kobe 653-0838 (Japan); Ueda, K.; Uraki, M.; Utsuro, M. [Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047 (Japan); Wang, S.Y. [Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Department of Physics, National Kaohsiung Normal University, Kaohsiung 824, Taiwan (China); Yosoi, M. [Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047 (Japan)

    2012-02-01

    We have developed a new cryogenic distillation system to purify Hydrogen-Deuteride (HD) gas for polarized HD targets in LEPS experiments at SPring-8. A small amount of ortho-H{sub 2} ({approx}0.01%) in the HD gas plays an important role in efficiently polarizing the HD target. Since there are 1-5% impurities of H{sub 2} and D{sub 2} in commercially available HD gases, it is necessary to purify the HD gas up to {approx}99.99%. The distillation system is equipped with a cryogenic distillation unit filled with many small stainless steel cells called 'Heli-pack'. The distillation unit consists of a condenser part, a rectification part, and a reboiler part. The unit is kept at the temperature of 17-21 K. The Heli-pack has a large surface area that makes a good contact between gases and liquids. An amount of 5.2 mol of commercial HD gas is fed into the distillation unit. Three trials were carried out to purify the HD gas by changing temperatures (17.5 K and 20.5 K) and gas extraction speeds (1.3 ml/min and 5.2 ml/min). The extracted gas was analyzed using a gas analyzer system combining a quadrupole mass spectrometer with a gas chromatograph. One mol of HD gas with a purity better than 99.99% has been successfully obtained for the first time. The effective NTP (Number of Theoretical Plates), which is an indication of the distillation performances, is obtained to be 37.2{+-}0.6. This value is in good agreement with a designed value of 37.9. The HD target is expected to be efficiently polarized under a well-controlled condition by adding an optimal amount of ortho-H{sub 2} to the purified HD gas.

  11. Plasma deposited fluorinated films on porous membranes

    Energy Technology Data Exchange (ETDEWEB)

    Gancarz, Irena [Department of Polymer and Carbon Materials, Wrocław University of Technology, 50-370 Wrocław (Poland); Bryjak, Marek, E-mail: marek.bryjak@pwr.edu.pl [Department of Polymer and Carbon Materials, Wrocław University of Technology, 50-370 Wrocław (Poland); Kujawski, Jan; Wolska, Joanna [Department of Polymer and Carbon Materials, Wrocław University of Technology, 50-370 Wrocław (Poland); Kujawa, Joanna; Kujawski, Wojciech [Nicolaus Copernicus University, Faculty of Chemistry, 7 Gagarina St., 87-100 Torun (Poland)

    2015-02-01

    75 KHz plasma was used to modify track etched poly(ethylene terephthalate) membranes and deposit on them flouropolymers. Two fluorine bearing monomers were used: perflourohexane and hexafluorobenzene. The modified surfaces were analyzed by means of attenuated total reflection infra-red spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy and wettability. It was detected that hexaflourobenxene deposited to the larger extent than perflourohaxane did. The roughness of surfaces decreased when more fluoropolymer was deposited. The hydrophobic character of surface slightly disappeared during 20-days storage of hexaflourobenzene modified membrane. Perfluorohexane modified membrane did not change its character within 120 days after modification. It was expected that this phenomenon resulted from post-reactions of oxygen with radicals in polymer deposits. The obtained membranes could be used for membrane distillation of juices. - Highlights: • Plasma deposited hydrophobic layer of flouropolymers. • Deposition degree affects the surface properties. • Hydrohilization of surface due to reaction of oxygen with entrapped radicals. • Possibility to use modified porous membrane for water distillation and apple juice concentration.

  12. Distilling hydrocarbon oils

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, J E

    1923-03-19

    In distilling mineral oils such as petroleum, shale oil, distillates and topped or residual oils, particularly to obtain lubricating oils, the distillation is carried out under reduced pressures below an absolute pressure of 25 mm. of mercury and preferably below about 5 mm. of mercury, and the distillate is collected in fractions determined by the physical characteristics, such as viscosity, flash point, fire point, etc. Superheated steam may be passed through the liquid during distillation. A horizontal cylindrical still provided with cross braces and peripheral ribs interrupted at the base is connected through a condensing coil immersed in a steam chest and a baffled chamber with distillate receiver and is evacuated by a pump. Steam from a boiler and superheater is injected into the still through a perforated pipe. Steam and light oil vapors passing from the chamber are condensed in a coil.

  13. Shale distillation

    Energy Technology Data Exchange (ETDEWEB)

    Blanding, F H

    1946-08-29

    A continuous method of distilling shale to produce valuable hydrocarbon oils is described which comprises providing a fluidized mass of the shale in a distillation zone, withdrawing hydrocarbon vapors from the zone, mixing fresh cold shale with the hydrocarbon vapors to quench the same, whereby the fresh shale is preheated, recovering hydrocarbon vapors and product vapors from the mixture and withdrawing preheated shale from the mixture and charging it to a shale distillation zone.

  14. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Heyl, G E

    1917-02-06

    The yield of oil obtained by distilling shale is increased by first soaking the shale with about 10 percent of its volume of a liquid hydrocarbon for a period of 24 hours or longer. Distillation is carried on up to a temperature of about 220/sup 0/C., and a further 10 percent of hydrocarbon is then added and the distillation continued up to a temperature of about 400/sup 0/C.

  15. Membrane for distillation including nanostructures, methods of making membranes, and methods of desalination and separation

    KAUST Repository

    Lai, Zhiping; Huang, Kuo-Wei; Chen, Wei

    2016-01-01

    In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, embodiments of the present disclosure provide membranes, methods of making the membrane, systems including the membrane, methods of separation, methods of desalination, and the like.

  16. Membrane for distillation including nanostructures, methods of making membranes, and methods of desalination and separation

    KAUST Repository

    Lai, Zhiping

    2016-01-21

    In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, embodiments of the present disclosure provide membranes, methods of making the membrane, systems including the membrane, methods of separation, methods of desalination, and the like.

  17. Sodium distiller II

    International Nuclear Information System (INIS)

    Goncalves, A.C.; Castro, P.M. e; Torres, A.R.; Correa, S.M.

    1990-01-01

    A sodium distiller allows the evaluation of the sodium purity, contained in plants and circuits of Fast Reactors. The sodium distillers of the IEN Reactor's Department was developed initially as a prototype, for the testing of the distillation process and in a second step, as a equipment dedicated to attendance the operation of these circuits. This last one was build in stainless steel, with external heat, rotating crucible of nickel for four samples, purge system for pipe cleaning and a sight glass that permits the observation of the distillation during all the operation. The major advantage of this equipment is the short time to do a distillation operation, which permits its routine utilization. As a consequence of the development of the distillers and its auxiliary systems an important amount of new information was gathered concerning components and systems behaviour under high temperature, vacuum and sodium. (author)

  18. Distilling tar; distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Brash, P; Young, W

    1866-09-17

    The tarry residue, which separates on treating crude shale oil with sulfuric acid, is redistilled, in the manner described in Specification No. 1278, A.D. 1866, together with shale. Previous to the distillation, the acid is neutralized with lime, or may be separated by blowing steam into the tar and adding salt. The purified tar thus obtained is absorbed by ashes, or is mixed with lime or other alkaline matter, or the shale may be mixed with lime and distilled with the tar, which is allowed to flow over and through the shale during the process. The tar obtained in the purification of natural paraffin may be similarly utilized.

  19. Experimental Validation of Hybrid Distillation-Vapor Permeation Process for Energy Efficient Ethanol-Water Separation

    Science.gov (United States)

    The energy demand of distillation-based systems for ethanol recovery and dehydration can be significant, particularly for dilute solutions. An alternative separation process integrating vapor stripping with a vapor compression step and a vapor permeation membrane separation step,...

  20. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    1938-07-05

    A process and apparatus for the destructive distillation at low temperature of mineral or organic material particularly oil shale, is given in which the process comprises distilling the material in a horizontal gaseous stream, subjecting the hot residues to the action of a gaseous stream containing a predetermined amount of oxygen so as to burn, at least partly, the carbon-containing substances, and the process uses the gases from this combustion for the indirect heating of the gases serving for the distillation.

  1. Dynamic Modeling and Control of Distributed Heat Transfer Mechanisms: Application to a Membrane Distillation Module

    KAUST Repository

    Eleiwi, Fadi

    2015-12-01

    Sustainable desalination technologies are the smart solution for producing fresh water and preserve the environment and energy by using sustainable renewable energy sources. Membrane distillation (MD) is an emerging technology which can be driven by renewable energy. It is an innovative method for desalinating seawater and brackish water with high quality production, and the gratitude is to its interesting potentials. MD includes a transfer of water vapor from a feed solution to a permeate solution through a micro-porous hydrophobic membrane, rejecting other non-volatile constituents present in the influent water. The process is driven by the temperature difference along the membrane boundaries. Different control applications and supervision techniques would improve the performance and the efficiency of the MD process, however controlling the MD process requires comprehensive mathematical model for the distributed heat transfer mechanisms inside the process. Our objective is to propose a dynamic mathematical model that accounts for the time evolution of the involved heat transfer mechanisms in the process, and to be capable of hosting intermittent energy supplies, besides managing the production rate of the process, and optimizing its energy consumption. Therefore, we propose the 2D Advection-Diffusion Equation model to account for the heat diffusion and the heat convection mechanisms inside the process. Furthermore, experimental validations have proved high agreement between model simulations and experiments with less than 5% relative error. Enhancing the MD production is an anticipated goal, therefore, two main control strategies are proposed. Consequently, we propose a nonlinear controller for a semi-discretized version of the dynamic model to achieve an asymptotic tracking for a desired temperature difference. Similarly, an observer-based feedback control is used to track sufficient temperature difference for better productivity. The second control strategy

  2. Membrane-based ethylene/ethane separation: The upper bound and beyond

    KAUST Repository

    Rungta, Meha; Zhang, Chen; Koros, William J.; Xu, Liren

    2013-01-01

    Ethylene/ethane separation via cryogenic distillation is extremely energy-intensive, and membrane separation may provide an attractive alternative. In this paper, ethylene/ethane separation performance using polymeric membranes is summarized

  3. Contaminant Permeation in the Ionomer-Membrane Water Processor (IWP) System

    Science.gov (United States)

    Kelsey, Laura K.; Finger, Barry W.; Pasadilla, Patrick; Perry, Jay

    2016-01-01

    The Ionomer-membrane Water Processor (IWP) is a patented membrane-distillation based urine brine water recovery system. The unique properties of the IWP membrane pair limit contaminant permeation from the brine to the recovered water and purge gas. A paper study was conducted to predict volatile trace contaminant permeation in the IWP system. Testing of a large-scale IWP Engineering Development Unit (EDU) with urine brine pretreated with the International Space Station (ISS) pretreatment formulation was then conducted to collect air and water samples for quality analysis. Distillate water quality and purge air GC-MS results are presented and compared to predictions, along with implications for the IWP brine processing system.

  4. Retrofit with membrane the Paraffin/Olefin separation

    Energy Technology Data Exchange (ETDEWEB)

    Motelica, A.; Bruinsma, O.S.L.; Kreiter, R.; Den Exter, M.J.; Vente, J.F. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-10-15

    Olefins, such as ethylene, propylene, and butadiene, are among the most produced intermediates in petrochemical industry. They are produced from a wide range of hydrocarbon feedstocks (ethane, propane, butane, naphtha, gas oil) via a cracking process. The last step in this process is the separation of olefins from other hydrocarbons, which is traditionally performed with distillation. As the physicochemical properties, such as volatility and boiling point, of the compounds are very similar, the purification becomes capital and energy intensive. For example, the top of an ethylene/ethane distillation column needs to be chilled to -30C and this requires large amount of electric energy consumption. The separation of butadiene from the C4-fraction is performed with the aid of an additional solvent. This solvent has to be regenerated at the cost of additional high temperature steam. To overcome these separation disadvantages of olefin/paraffin separation, different separation methods have been investigated and proposed in recent years. Suggested options are based on better heat integration of the overall process, or on novel separation systems such as Heat Integrated Distillation Columns, membrane separation, adsorption-desorption systems or on hybrid separation methods, for example, distillation combined with membrane separation.

  5. Wetting dynamics at high values of contact line speed

    OpenAIRE

    Пономарев, К. О.; Феоктистов, Дмитрий Владимирович; Орлова, Евгения Георгиевна

    2015-01-01

    Experimental results analyses of dynamic contact angle change under the conditions of substrate wetting by distilled water at high values of the contact line speed was conducted. Three spreading modes for copper substrates with different roughness were selected: drop formation, spreading and equilibrium contact angle formation. Peculiarity of droplet spreading on superhydrophobic surface is found. It consists in a monotonic increase of the advancing dynamic contact angle. The effect of the dr...

  6. Distillation of oil-bearing minerals

    Energy Technology Data Exchange (ETDEWEB)

    1952-05-21

    In the process of distilling oil-bearing minerals such as oil shale which disintegrates during distillation, wherein the subdivided minerals are subjected to a distillation temperature in the form of a highly turbulent dense mass fluidized by an upwardly flowing gasiform medium in a distillation zone and the heat required by the distillation is supplied by burning solid distillation residue with a combustion-supporting gas in the form of a fluidized mass of solids in a separate combustion zone at a temperature substantially higher than the distillation temperature and returning solid combustion residue substantially at the higher temperature to the distillation zone. The steps of starting up the process which consists of maintaining in the distillation and combustion zones dense turbulent fluidized beds of non-disintegrating solids, circulating the non-disintegrating solids between said beds, heating the circulating solids by an auxiliary heat supply until the bed in the distillation zone has reached at least the distillation temperature, thereafter charging fresh oil-bearing minerals to the bed in the distillation zone, continuing the circulation, withdrawing solids which have passed through the combustion zone at a rate adequate to maintain a solids balance, supplying the combustion-supporting gas to the combustion zone to cause the combustion of the residue, and discontinuing the auxilary heating when sufficient heat for the distillation is being generated in the combustion zone.

  7. CONTACT RESISTANCE MODELING

    Directory of Open Access Journals (Sweden)

    S. V. LOSKUTOV

    2018-05-01

    Full Text Available Purpose. To determine the contribution of the real contact spots distribution in the total conductivity of the conductors contact. Methodology. The electrical contact resistance research was carried out on models. The experimental part of this work was done on paper with a graphite layer with membranes (the first type and conductive liquids with discrete partitions (the second type. Findings. It is shown that the contact electrical resistance is mainly determined by the real area of metal contact. The experimental dependence of the electrical resistance of the second type model on the distance between the electrodes and the potential distribution along the sample surface for the first type model were obtained. The theoretical model based on the principle of electric field superposition was considered. The dependences obtained experimentally and calculated by using the theoretical model are in good agreement. Originality. The regularity of the electrical contact resistance formation on a large number of membranes was researched for the first time. A new model of discrete electrical contact based on the liquid as the conducting environment with nuclear membrane partitions was developed. The conclusions of the additivity of contact and bulk electrical resistance were done. Practical value. Based on these researches, a new experimental method of kinetic macroidentation that as a parameter of the metal surface layer deformation uses the real contact area was developed. This method allows to determine the value of average contact stresses, yield point, change of the stress on the depth of deformation depending on the surface treatment.

  8. Distillation of oil-bearing minerals

    Energy Technology Data Exchange (ETDEWEB)

    1952-12-03

    A process of distilling oil-bearing minerals of the type of oil shale which disintegrate during distillation consists of subjecting the subdivided minerals to a distillation temperature in the form of a highly turbulent dense mass fluidized by an upwardly flowing gasiform medium in a distillation zone and supplying the heat required for the distillation by burning solid distillation residue with a combustion-supporting gas in the form of a fluidized mass of solids in a separate combustion zone at a combustion temperature and returning solid combustion residue substantially at the combustion temperature to the distillation zone. Combustion temperature is positively maintained at a figure not exceeding 1,200/sup 0/F and at a figure which is not substantially more than 50/sup 0/F higher than the distillation temperature.

  9. Extended synaptotagmins are Ca2+-dependent lipid transfer proteins at membrane contact sites.

    Science.gov (United States)

    Yu, Haijia; Liu, Yinghui; Gulbranson, Daniel R; Paine, Alex; Rathore, Shailendra S; Shen, Jingshi

    2016-04-19

    Organelles are in constant communication with each other through exchange of proteins (mediated by trafficking vesicles) and lipids [mediated by both trafficking vesicles and lipid transfer proteins (LTPs)]. It has long been known that vesicle trafficking can be tightly regulated by the second messenger Ca(2+), allowing membrane protein transport to be adjusted according to physiological demands. However, it remains unclear whether LTP-mediated lipid transport can also be regulated by Ca(2+) In this work, we show that extended synaptotagmins (E-Syts), poorly understood membrane proteins at endoplasmic reticulum-plasma membrane contact sites, are Ca(2+)-dependent LTPs. Using both recombinant and endogenous mammalian proteins, we discovered that E-Syts transfer glycerophospholipids between membrane bilayers in the presence of Ca(2+) E-Syts use their lipid-accommodating synaptotagmin-like mitochondrial lipid binding protein (SMP) domains to transfer lipids. However, the SMP domains themselves cannot transport lipids unless the two membranes are tightly tethered by Ca(2+)-bound C2 domains. Strikingly, the Ca(2+)-regulated lipid transfer activity of E-Syts was fully recapitulated when the SMP domain was fused to the cytosolic domain of synaptotagmin-1, the Ca(2+)sensor in synaptic vesicle fusion, indicating that a common mechanism of membrane tethering governs the Ca(2+)regulation of lipid transfer and vesicle fusion. Finally, we showed that microsomal vesicles isolated from mammalian cells contained robust Ca(2+)-dependent lipid transfer activities, which were mediated by E-Syts. These findings established E-Syts as a novel class of LTPs and showed that LTP-mediated lipid trafficking, like vesicular transport, can be subject to tight Ca(2+)regulation.

  10. Experimental Evaluation of Hybrid Distillation-Vapor Permeation Process for Efficient Ethanol Recovery from Ethanol-Water Mixtures

    Science.gov (United States)

    The energy demand of distillation-based systems for ethanol recovery and dehydration can be significant, particularly for dilute solutions [1]. An alternative separation process integrating vapor stripping with a vapor compression step and a vapor permeation membrane separation ...

  11. Periodic mesoporous organosilica-doped nanocomposite membranes and systems including same

    KAUST Repository

    Hammami, Mohamed Amen

    2017-12-28

    A periodic mesoporous organosilica (PMO) nanoparticle functionalized nanocomposite membrane (NCM) for membrane distillation, the NCM including: polymer fibers such as polyetherimide fibers aggregated into a matrix; and hydrophobic PMO nanoparticles disposed on the polymer fibers. The PMO nanoparticles include a framework connected by organic groups and pentafluorophenyl groups. Good membrane flux and anti-fouling was demonstrated. Membranes can be prepared by electrospinning.

  12. Periodic mesoporous organosilica-doped nanocomposite membranes and systems including same

    KAUST Repository

    Hammami, Mohamed Amen; Francis, Lijo; Croissant, Jonas; Ghaffour, NorEddine; Alsaiari, Shahad; Khashab, Niveen M.

    2017-01-01

    A periodic mesoporous organosilica (PMO) nanoparticle functionalized nanocomposite membrane (NCM) for membrane distillation, the NCM including: polymer fibers such as polyetherimide fibers aggregated into a matrix; and hydrophobic PMO nanoparticles disposed on the polymer fibers. The PMO nanoparticles include a framework connected by organic groups and pentafluorophenyl groups. Good membrane flux and anti-fouling was demonstrated. Membranes can be prepared by electrospinning.

  13. A general model for membrane-based separation processes

    DEFF Research Database (Denmark)

    Soni, Vipasha; Abildskov, Jens; Jonsson, Gunnar Eigil

    2009-01-01

    behaviour will play an important role. In this paper, modelling of membrane-based processes for separation of gas and liquid mixtures are considered. Two general models, one for membrane-based liquid separation processes (with phase change) and another for membrane-based gas separation are presented....... The separation processes covered are: membrane-based gas separation processes, pervaporation and various types of membrane distillation processes. The specific model for each type of membrane-based process is generated from the two general models by applying the specific system descriptions and the corresponding...

  14. Separation setup for the light water detritiation process in the water-hydrogen system based on the membrane contact devices

    International Nuclear Information System (INIS)

    Rozenkevich, M. B.; Rastunova, I. L.; Prokunin, S. V.

    2008-01-01

    Detritiation of light water wastes down to a level permissible to discharge into the environment while simultaneously concentrating tritium to decrease amount of waste being buried is a constant problem. The laboratory setup for the light water detritiation process is presented. The separation column consists of 10 horizontally arranged perfluorosulphonic acid Nafion-type membrane contact devises and platinum catalyst (RCTU-3SM). Each contact device has 42.3 cm 2 of the membrane and 10 cm 3 of the catalyst. The column is washed by tritium free light water (L H2O ) and the tritium-containing flow (F HTO ) feeds the electrolyser at λ = G H2 /L H2O = 2. A separation factor of 66 is noted with the device at 336 K and 0.145 MPa. (authors)

  15. Distillation apparatus for solid materials

    Energy Technology Data Exchange (ETDEWEB)

    Lurmann, F

    1860-06-26

    The distillation room is continuously charged by the charging mechanism with the material to be distilled. The distillation products pass into the chamber, where they are drawn out through the tube for purifying. The distillation residue is finally pushed out by the fresh material from the room and falls in the common room, from which it is removed through the air-tight door. In the canals enclosing the room heating gas circulates, which carries to the room the heat necessary for the distillation.

  16. Cyclic voltammetric investigations of microstructured and platinum-covered glassy carbon electrodes in contact with a polymer electrolyte membrane

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, G G; Veziridis, Z; Staub, M [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Freimuth, H [Inst. fuer Mikrotechnik Mainz IMM, Mainz (Germany)

    1997-06-01

    Model gas diffusion electrodes were prepared by microstructuring glassy carbon surfaces with high aspect ratios and subsequent deposition of platinum. These electrodes were characterized by hydrogen under-potential deposition (H-upd) in contact with a polymer electrolyte membrane employing cyclic voltametry. H-upd was found on platinum areas not in direct contact to the solid electrolyte, as long as a continuous platinum-path existed. A carbon surface between platinum acts as barrier for H-upd. (author) 4 figs., 5 refs.

  17. Purification Simulation With Vapor Permeation and Distillation-Adsorption In Bioethanol Plant

    OpenAIRE

    Misri Gozan; Mia Sari Setiawan; Kenny Lischer

    2017-01-01

    High purity of Bioethanol is required in biofuel mixing with gasoline (EXX). In bioethanol production line, the azeotropic property of ethanol-water becomes the barrier for purification process. This study examined two bioethanol separation processes by support of simulation tools, Superpro Designer 9.0 software. Ethanol purity and a low costeconomical process were the major considerations. Purification method of vapor permeation membrane technology was compared with distillation-adsorption m...

  18. 27 CFR 27.40 - Distilled spirits.

    Science.gov (United States)

    2010-04-01

    ... OF THE TREASURY LIQUORS IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on all... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distilled spirits. 27.40...

  19. Membrane Distillation and Applications for Water Purification in Thermal Cogeneration. Pilot Plant Trials

    Energy Technology Data Exchange (ETDEWEB)

    Kullab, Alaa; Martin, Andrew

    2007-12-15

    Water treatment is an important auxiliary process in all thermal cogeneration plants. In this context membrane distillation (MD) is a novel technology that is potentially advantageous to technologies like reverse osmosis in the following ways: ability to utilize low-grade heat; reduced sensitivity to fluctuations in pH or salt concentrations; and lower capital and operation and maintenance costs (assumed in the case of fully-developed technology only). This research is a continuation of a Varmeforsk prestudy (report no. 909) and encompasses field trials at Idbaecken Combined Heat and Power (CHP) Facility (Nykoeping). Target groups for this study include environmental engineers with particular interest in emerging water purification technologies. The test rig consisted of a five-module MD unit capable of producing 1-2 m3/day purified water. District heating supply was employed for heating; feed stocks include municipal water and flue gas condensate. Field trials can be divided into three phases: (1) parametric study of yield; (2) long term operation with municipal water as feed stock; and (3) evaluation of flue gas condensate as a feed stock. Testing commenced in the beginning of April 2006. The performance of MD concerning production rate is highly dependent on the feed stock temperature, flow rate and temperature difference across the membrane. Initial results for municipal water feed stocks showed that product water fluxes were in line with previous experiments, thus confirming the findings made in the prestudy. Connecting several MD modules in series has the advantage of reducing the electrical energy consumption needed for recirculation; the penalty comes in less efficient operation from flux point of view. This is more critical in the case of low flow rates, and hence much careful design studies are needed to optimize the system. Regarding the long term performance, the test period lasted for 13 days on a continuous operation basis before the first flux

  20. 21 CFR 184.1848 - Starter distillate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Starter distillate. 184.1848 Section 184.1848 Food... Specific Substances Affirmed as GRAS § 184.1848 Starter distillate. (a) Starter distillate (butter starter distillate) is a steam distillate of the culture of any or all of the following species of bacteria grown on...

  1. Distillation of solid carbonaceous material

    Energy Technology Data Exchange (ETDEWEB)

    Burney, C D

    1918-08-31

    A method of distilling carbonaceous material at low or moderate temperatures is described in which the main supply of gases for heating the material under treatment is generated in a combustion chamber located externally of the retort chamber from which combustion chamber the gases are withdrawn and passed under control through hollow elements located within the retort chamber in such manner as to insure the production of the desired temperature gradient along the length of the retort, the said elements being so constructed that they serve to bring the heating gases into indirect contact with the material undergoing treatment while also moving the material progressively through the retort in the opposite direction to that in which the heating gases flow.

  2. Toxicity of middle distillates from dermal exposure.

    Science.gov (United States)

    Koschier, F J

    1999-02-01

    This report focuses on recent studies that investigated the effects of kerosine dermal exposure on neurotoxicity and reproductive/developmental toxicity. Background toxicity information will also be reviewed for kerosine range mid distillates. The kerosine range mid distillates have a carbon range of C9-C16 and have a boiling range of 302-554 degrees F (150-290 degrees C). This category includes kerosine, aviation fuels (e.g., Jet A, JP-5 and JP-8), no. 1 fuel oil and diesel fuel oil. In general, the kerosine range mid distillates demonstrate relatively low acute toxicity by any route of exposure. High inhalation exposures can induce central nervous system depression characterized by ataxia, hypoactivity and prostration. Kerosines are known to cause skin irritation and inflammation under conditions of acute and repeated exposure in animals and humans, but are only slightly irritating to the eye and are not skin sensitizers. In addition, the absorption of kerosine range mid distillates through the skin has been demonstrated to be fairly rapid, but limited to approximately 10-15% of the applied dose after 24 hours. The kerosine range mid distillates are generally inactive in genetic toxicity tests although positive studies have been reported. Positive results, while at times equivocal, have been reported for straight run kerosine and jet fuel A in the mouse lymphoma assay with metabolic activation, and hydrodesulfurized kerosine (mouse) and jet fuel A (rat) in the bone marrow cytogenetic assay. Effects on the nervous and reproductive systems have been reported in humans and experimental animals under conditions where inhalation and dermal exposure to specific kerosine type fuels are sometimes difficult to separate. Recent laboratory studies have addressed this point and examined the effects of dermal exposure. In these studies, rats were exposed to hydrodesulfurized kerosine by skin application to determine the potential of dermal contact to cause reproductive

  3. Extractive distillation of nitric acid using the two-pot concept

    International Nuclear Information System (INIS)

    Counce, R.M.; Groenier, W.S.; Holland, W.D.; Jubin, R.T.; North, E.D.; Thompson, L.E. Jr.; Hebble, T.L.

    1982-12-01

    Experiments have confirmed the validity of a novel design for a nitric acid concentration system for use in shielded nuclear fuel reprocessing plants. Current plans for producing the scrub solution for the IODOX process require the concentration and recycle of low strength ( 3 ) 2 as the solvent and features two pots: an extractive distillation pot in which a concentrated acid product is obtained by contacting the acid feed with the solvent and a solvent recovery pot in which the solvent is dehydrated and recovered for recycle. In these experiments, a concentrated product of 89 wt % nitric acid was produced from azeotropic feed. The available vapor-liquid equilibria data for the Mg(NO 3 ) 2 -HNO 3 -H 2 O system has been empirically correlated, and a design methodology has been developed for the two-pot extractive distillation process

  4. Hierarchical Composite Membranes with Robust Omniphobic Surface Using Layer-By-Layer Assembly Technique

    KAUST Repository

    Woo, Yun Chul; Kim, Youngjin; Yao, Minwei; Tijing, Leonard Demegilio; Choi, Juneseok; Lee, Sangho; Kim, Seunghyun; Shon, Hokyong

    2018-01-01

    gave the LBL membrane an omniphobic property, as indicated by its good wetting resistance. The membrane performed a stable air gap membrane distillation (AGMD) flux of 11.22 L/m2h with very high salt rejection using reverse osmosis brine from coal seam

  5. Composite perfluorohydrocarbon membranes, their preparation and use

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yong; Bikson, Benjamin

    2017-04-04

    Composite porous hydrophobic membranes are prepared by forming a perfluorohydrocarbon layer on the surface of a preformed porous polymeric substrate. The substrate can be formed from poly (aryl ether ketone) and a perfluorohydrocarbon layer can be chemically grafted to the surface of the substrate. The membranes can be utilized for a broad range of fluid separations, such as microfiltration, nanofiltration, ultrafiltration as membrane contactors for membrane distillation and for degassing and dewatering of fluids. The membranes can further contain a dense ultra-thin perfluorohydrocarbon layer superimposed on the porous poly (aryl ether ketone) substrate and can be utilized as membrane contactors or as gas separation. membranes for natural gas treatment and gas dehydration.

  6. An analytical model and parametric study of electrical contact resistance in proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhiliang; Wang, Shuxin; Zhang, Lianhong [School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China); Hu, S. Jack [Department of Mechanical Engineering, The University of Michigan, Ann Arbor, MI 48109-2125 (United States)

    2009-04-15

    This paper presents an analytical model of the electrical contact resistance between the carbon paper gas diffusion layers (GDLs) and the graphite bipolar plates (BPPs) in a proton exchange membrane (PEM) fuel cell. The model is developed based on the classical statistical contact theory for a PEM fuel cell, using the same probability distributions of the GDL structure and BPP surface profile as previously described in Wu et al. [Z. Wu, Y. Zhou, G. Lin, S. Wang, S.J. Hu, J. Power Sources 182 (2008) 265-269] and Zhou et al. [Y. Zhou, G. Lin, A.J. Shih, S.J. Hu, J. Power Sources 163 (2007) 777-783]. Results show that estimates of the contact resistance compare favorably with experimental data by Zhou et al. [Y. Zhou, G. Lin, A.J. Shih, S.J. Hu, J. Power Sources 163 (2007) 777-783]. Factors affecting the contact behavior are systematically studied using the analytical model, including the material properties of the two contact bodies and factors arising from the manufacturing processes. The transverse Young's modulus of chopped carbon fibers in the GDL and the surface profile of the BPP are found to be significant to the contact resistance. The factor study also sheds light on the manufacturing requirements of carbon fiber GDLs for a better contact performance in PEM fuel cells. (author)

  7. Regenerative adsorption distillation system

    KAUST Repository

    Ng, Kim Choon; Thu, Kyaw; Amy, Gary; Chunggaze, Mohammed; Al-Ghasham, Tawfiq

    2013-01-01

    There is provided a regenerative adsorption distillation system comprising a train of distillation effects in fluid communication with each other. The train of distillation effects comprises at least one intermediate effect between the first and last distillation effects of the train, each effect comprising a vessel and a condensing tube for flow of a fluid therein. The system further comprises a pair of adsorption-desorption beds in vapour communication with the last effect and at least one intermediate effect, wherein the beds contain an adsorbent that adsorbs vapour from the last effect and transmits desorbed vapour into at least one of the intermediate effect.

  8. Regenerative adsorption distillation system

    KAUST Repository

    Ng, Kim Choon

    2013-12-26

    There is provided a regenerative adsorption distillation system comprising a train of distillation effects in fluid communication with each other. The train of distillation effects comprises at least one intermediate effect between the first and last distillation effects of the train, each effect comprising a vessel and a condensing tube for flow of a fluid therein. The system further comprises a pair of adsorption-desorption beds in vapour communication with the last effect and at least one intermediate effect, wherein the beds contain an adsorbent that adsorbs vapour from the last effect and transmits desorbed vapour into at least one of the intermediate effect.

  9. Distillation of bituminous shale

    Energy Technology Data Exchange (ETDEWEB)

    Seguin, M

    1875-02-16

    The retort with its accessories constitutes a distillation apparatus for shale composed of a cylindrical, vertical, fixed, tubular, and of ring form metal retort. Also it is comprised of a special hearth of large dimensions in the form of a circular pocket receiving from the retort as heating agent the distilled shale and emitting by radiation the heat that makes the distillation apparatus for the shale act.

  10. Hybrid Membrane System for Industrial Water Reuse

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-08-01

    This factsheet describes a project that developed and demonstrated a new hybrid system for industrial wastewater treatment that synergistically combines a forward osmosis system with a membrane distillation technology and is powered by waste heat.

  11. Low Temperature Geothermal Resource Assessment for Membrane Distillation Desalination in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Akar, Sertac; Turchi, Craig

    2017-05-01

    Substantial drought and declines in potable groundwater in the United States over the last decade has increased the demand for fresh water. Desalination of saline water such as brackish surface or groundwater, seawater, brines co-produced from oil and gas operations, industrial wastewater, blow-down water from power plant cooling towers, and agriculture drainage water can reduce the volume of water that requires disposal while providing a source of high-quality fresh water for industrial or commercial use. Membrane distillation (MD) is a developing technology that uses low-temperature thermal energy for desalination. Geothermal heat can be an ideal thermal-energy source for MD desalination technology, with a target range of $1/m3 to $2/m3 for desalinated water depending on the cost of heat. Three different cases were analyzed to estimate levelized cost of heat (LCOH) for integration of MD desalination technology with low-grade geothermal heat: (1) residual heat from injection brine at a geothermal power plant, (2) heat from existing underutilized low-temperature wells, and (3) drilling new wells for low-temperature resources. The Central and Western United States have important low-temperature (<90 degrees C) geothermal resource potential with wide geographic distribution, but these resources are highly underutilized because they are inefficient for power production. According to the USGS, there are 1,075 identified low temperature hydrothermal systems, 55 low temperature sedimentary systems and 248 identified medium to high temperature geothermal systems in the United States. The estimated total beneficial heat potential from identified low temperature hydrothermal geothermal systems and residual beneficial heat from medium to high temperature systems is estimated as 36,300 MWth, which could theoretically produce 1.4 to 7 million m3/day of potable water, depending on desalination efficiency.

  12. Distilling shale and coal

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, H; Young, G

    1923-01-09

    In a process of recovering oil from shale or coal the material is ground and may be subjected to a cleaning or concentrating process of the kind described in Specification 153,663 after which it is distilled in a furnace as described in Specification 13,625/09 the sections of the furnace forming different temperature zones, and the rate of the passage of the material is regulated so that distillation is complete with respect to the temperature of each zone, the whole distillation being accomplished in successive stages. The vapors are taken off at each zone and superheated steam may be passed into the furnace at suitable points and the distillation terminated at any stage of the process.

  13. Herbal distillates: A new era of grape marc distillates with enriched antioxidant profile.

    Science.gov (United States)

    Andreou, Vasiliki; Strati, Irini F; Fotakis, Charalambos; Liouni, Maria; Zoumpoulakis, Panagiotis; Sinanoglou, Vassilia J

    2018-07-01

    Grape marc distillates are traditional alcoholic beverages, produced mostly in the Mediterranean countries. The present study proposes the enrichment of a Greek traditional grape marc distillate (tsikoudia) with selected herbs to enhance its natural antioxidants and functional properties. Total phenolic content, the antiradical and antioxidant activities, as well as the phenolic and sugar profiles using NMR and FT-IR spectroscopy were evaluated. The enrichment of distillates with Syzygium aromaticum L., Jasminum officinale L. and Eucalyptus globulus Labill. exhibited the highest total phenolic content as well as the highest antioxidant and antiradical activities, whereas the lowest values were observed with Hippophae rhamnoides L. and Lycium Barbarum Mill. The implementation of NMR and FT-IR spectroscopies attested to the presence of phenolic compounds and of specific carbohydrates in herbal distillates, postulating their migration from selected herbal species to tsikoudia and probably contributing to their organoleptic characteristics. The target of this approach leads to new added-value distillates with enhanced characteristics. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Treatment with activated carbon and other adsorbents as an effective method for the removal of volatile compounds in agricultural distillates.

    Science.gov (United States)

    Balcerek, Maria; Pielech-Przybylska, Katarzyna; Patelski, Piotr; Dziekońska-Kubczak, Urszula; Jusel, Tomaš

    2017-05-01

    This study investigates the effect of treatment with activated carbon and other adsorbents on the chemical composition and organoleptics of a barley malt-based agricultural distillate. Contact with activated carbon is one of the methods by which the quality of raw distillates and spirit beverages can be improved. Samples placed in contact with 1 g activated carbon (SpiritFerm) per 100 ml distillate with ethanol content of 50% v/v for 1 h showed the largest reductions in the concentrations of most volatile compounds (aldehydes, alcohols, esters). Increasing the dose of adsorbent to over 1 g 100 ml -1 did not improve the purity of the agricultural distillate significantly. Of the tested compounds, acetaldehyde and methanol showed the lowest adsorption on activated carbon. The lowest concentrations of these congeners (expressed in mg l -1 alcohol 100% v/v) were measured in solutions with ethanol contents of 70-80% v/v, while solutions with an alcoholic strength by volume of 40% did not show statistically significant decreases in these compounds in relation the control sample. The reductions in volatile compounds were compared with those for other adsorbents based on silica or activated carbon and silica. An interesting alternative to activated carbon was found to be an adsorbent prepared from activated carbon and silica (Spiricol). Treatment with this adsorbent produced distillate with the lowest concentrations of acetaldehyde and isovaleraldehyde, and led to the greatest improvement in its organoleptics.

  15. Membrane processes in nuclear technologies

    International Nuclear Information System (INIS)

    Zakrzewska-Trznadel, G.

    2006-01-01

    to the pressure-driven processes, e.g. ultrafiltration and reverse osmosis, which were studied on a laboratory and pilot scale. Verification of the potential application of reverse osmosis on an industrial scale for treatment of liquid low- and intermediate-level radioactive wastes has been carried out with the installation particularly designed and constructed for the Department of Radioactive Waste Processing, Institute of Atomic Energy at Swierk. The thin-layer composite membranes made from a cross-linked aromatic polyamide of high retention of NaCl (99,4-99,7%) were applied in this process. It has been proved that a three-stage installation enables the radioactive waste of specific radioactivity below 10 5 Bq/dm 3 to be cleaned down to 10 Bq/dm 3 in permeate, with simultaneous 7-15-fold reduction of the activity in the concentrate. The results of own studies concerning the removal of selected radionuclides from model aqueous solutions and radioactive wastes with ultra-filtration enhanced by complexation and sorption were also presented in this work. In these cases, the mineral (ceramic) porous membranes made from a-alumina, titanium and zirconium oxides were applied. These membranes exhibited a high resistance against ionizing radiation, aggressive chemical environment and high temperatures. The high effectiveness of removal of the main components of liquid radioactive waste like 134 Cs, 137 Cs, 60 Co, 124 Sb, 85 Sr, 152 Eu and 154 Eu with a hybrid ultrafiltration/complexation process has been experimentally proved. The effects of this type of complexing agent, its concentration and pH of the processed solution on the complexation effectiveness have been studied. Efficacy of the method was tested with real radioactive wastes. The monograph performs results of the studies on membrane distillation which has been proposed by the author for processing of liquid radioactive wastes, and the analysis of its applicability for nuclear desalination and the production of

  16. Fouling-Resistant Membranes for Treating Concentrated Brines for Water Reuse in Advanced Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hendren, Zachary [RTI International, Research Triangle Park, NC (United States); Choi, Young Chul [RTI International, Research Triangle Park, NC (United States)

    2014-10-14

    The high total dissolved solids (TDS) levels in the wastewater quality generated from unconventional oil and gas development make the current state-of-the art approach to water treatment/disposal untenable. Our proposed membrane technology approach addresses the two major challenges associated with this water: 1) the membrane distillation process removes the high TDS content, which is often 8 times higher than that of seawater, and 2) our novel membrane coating prevents the formation of scale that would otherwise pose a significant operational hurdle. This is accomplished through next-generation electrically conductive membranes that mitigate fouling beyond what is currently possible, and allow for the flexibility to treat to the water to levels desirable for multiple reuse options, thus reducing fresh water withdrawal, all the way to direct disposal into the environment. The overall project objective was to demonstrate the efficacy of membrane distillation (MD) as a cost-savings technology to treat concentrated brines (such as, but not limited to, produced waters generated from fossil fuel extraction) that have high levels of TDS for beneficial water reuse in power production and other industrial operations as well as agricultural and municipal water uses. In addition, a novel fouling-resistant nanocomposite membrane was developed to reduce the need for chemicals to address membrane scaling due to the precipitation of divalent ions in high-TDS waters and improve overall MD performance via an electrically conductive membrane distillation process (ECMD). This anti-fouling membrane technology platform is based on incorporating carbon nanotubes (CNTs) into the surface layer of existing, commercially available MD membranes. The CNTs impart electrical conductivity to the membrane surface to prevent membrane scaling and fouling when an electrical potential is applied.

  17. Transport phenomena in gas-selective silica membranes

    DEFF Research Database (Denmark)

    Boffa, Vittorio

    Upcoming technology platforms for green fuel production require the development of advanced molecular separation processes for recovering dry liquid biofuels [1,2], biomethane [2] and hydrogen [3]. Replacement of extractive distillation, cryodistillation and adsorption processes by membrane units...

  18. Polyethersulfone/clay membranes and its water permeability; Membranas de polietersulfona/argila e sua permeabilidade a agua

    Energy Technology Data Exchange (ETDEWEB)

    Cavalho, Thamyres Cardoso de; Medeiros, Vanessa da Nobrega; Araujo, Edcleide Maria de; Lira, Helio Lucena, E-mail: thamyrescc@gmail.com, E-mail: vanismedeiros@gmail.com, E-mail: edcleide.araujo@ufcg.edu.br, E-mail: helio.lira@ufcg.edu.br [Universidade Federal de Campina Grande (UAEMa/CCT/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Leite, Amanda Melissa Damiao, E-mail: amanda.leite@ect.ufrn.br [Universidade Federal do Rio Grande do Norte (ECT/UFRN), Natal, RN (Brazil). Escola de Ciencia e Tecnologia

    2017-04-15

    Membranes can be considered polymeric or inorganic films that function as a semipermeable barrier to filtration on a molecular scale, separating two phases and restricting, totally or partially, the transportation of one or more chemical species (solute) present in the solution. Therefore, the aim of this work is to produce polyethersulfone membranes (PES) and polyethersulfone/clay by phase inversion technique and evaluate the presence of clay in obtaining membranes for wastewater treatment. The used solvent was dimethylformamide (DMF) and clays were Brasgel PA (MMT) and Cloisite Na (CL Na) in the proportion of 3 to 5% (wt.). By Xray diffraction (XRD), the membranes with 3% of MMT and CL Na clays apparently had partially exfoliated structures. For the composition with 5% of CL Na a small peak was observed, which indicates that this is possibly an intercalated structure or microcomposite. By scanning electron microscopy (SEM), visualizes that the pure surface of the pure PES membrane a structure apparently without pores was observed in the used magnification and without roughness surface when compared to membranes with clay. The measurements of contact angle indicated that the inclusion of clay altered the wetting ability of the membranes. The flow with distilled water for all membranes started high and over time reached a stabilization level. Thus, it can be concluded that the presence and the content of clay altered the morphology of the membrane, contributing to an increase in water flow. (author)

  19. Hybrid wind-power-distillation plant

    Directory of Open Access Journals (Sweden)

    Ninić Neven

    2012-01-01

    Full Text Available This paper reports and elaborates on the idea of a solar distiller and an offshore wind power plant operating together. The subject under discussion is a single-stage solar distillation plant with vaporization, using adiabatic expansion in the gravitational field inside a wind power plant supporting column. This scheme divides investment costs for electric power and distillate production. In the region of the Adriatic Sea, all electric power produced could be “converted” to hydrogen using less than 10% of the distillate produced.

  20. Zone distillation: a new purification method

    International Nuclear Information System (INIS)

    Kravchenko, A.I.

    2011-01-01

    The features of zone distillation (with zone melting of refined material and with pulling of condensate) as a new purification method are shown. The method is based on similarity of equations of distillation and crystallization refining. The analogy between some distillation and condensation methods (particularly between zone distillation and zone recrystallization) is should up

  1. Shale distillation

    Energy Technology Data Exchange (ETDEWEB)

    Blanding, F H

    1948-08-03

    A continuous method of distilling shale to produce valuable hydrocarbon oils is described, which comprises providing a fluidized mass of the shale in a distillation zone, withdrawing hydrocarbon vapors containing shale fines from the zone, mixing sufficient fresh cold shale with the hydrocarbon vapors to quench the same and to cause condensation of the higher boiling constituents thereof, charging the mixture of vapors, condensate, and cold shale to a separation zone where the shale is maintained in a fluidized condition by the upward movement of the hydrocarbon vapors, withdrawing condensate from the separation zone and recycling a portion of the condensate to the top of the separation zone where it flows countercurrent to the vapors passing therethrough and causes shale fines to be removed from the vapors by the scrubbing action of the condensate, recovering hydrocarbon vapors and product vapors from the separation zone, withdrawing preheated shale from the separation zone and charging it to a shale distillation zone.

  2. Destructive distillation: oils

    Energy Technology Data Exchange (ETDEWEB)

    West, J; Glover, S

    1918-01-31

    Canned and other coals are destructively distilled in continuously operated vertical retorts which at their upper portions are maintained at temperatures suitable for low temperature oil distillation such as about 700/sup 0/C, and at their lower portions the temperature is higher and such as to be suitable for the production of gas, e.g., about 1400/sup 0/C. Superheated steam is introduced into the lower portion of the retort, preferably by means of the arrangement described in Specification 120,458, and this is converted into blue water gas which assists the distillation in the center of the coal charge. The retorts are preferably such as are described in Specifications 2663/07 and 7757/14.

  3. Molecular Probes: An Innovative Technology for Monitoring Membrane Processes

    Science.gov (United States)

    Santoro, Sergio

    The ultimate objective of this study is to use molecular probes as an innovative and alternative technology contributing to the advance of membrane science by monitoring membrane processes in-situ, on-line and at sub-micron scale. An optical sensor for oxygen sensing was developed by the immobilization of tris (1,10-phenanthroline) ruthenium (II) (Ru(phen)3) in a dense polymeric membrane made of polystyrene (PS) or Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The emission of the probe was quenched by both the temperature and by the oxygen. Moreover, the oxygen sensitivity was affected by the oxygen permeability of the membrane. The evaluation of the oxygen concentration is prone to errors since the emission of a single probe depends on several parameters (i.e. optical path, source intensity). The correction of these artefacts was obtained by the immobilization of a second luminescent molecule non-sensitive to the oxygen, Coumarin. The potential of the luminescent ratiometric sensor for the non-invasive monitoring of oxygen in food packaging using polymeric films with different oxygen permeability was evaluated. Emphasis was given to the efficiency of the optical sensor for the on-line, in-situ and non invasive monitoring of the oxygen by comparing the experimental data with a model which takes into account the oxygen permeability of the packaging materials evaluated independently. A nano-thermometer based on silica nano-particles doped with Ru(phen)3 was developed. A systematic study shows how it is possible to control the properties of the nano-particles as well as their temperature sensitivity. The nano-thermometer was immobilized on a membrane surface by dip-coating providing information about the temperature on the membrane surface. Hydrophobic porous membrane made of Poly(vinylidene fluoride) was prepared via electrospinning and employed in a direct contact membrane distillation process. Using a designed membrane module and a membrane doped with Ru

  4. Use of gamma and UV radiation in grafting hydrogel polymers to membranes

    International Nuclear Information System (INIS)

    Baker, L.; Hill, D.J.T.; Whittaker, A.; Hunter, D.; Davis, T.P.

    1998-01-01

    Full text: Dimethylacrylamide and N-isopropylacrylamide hydrogels are useful for their ability to absorb large amounts of water and for their thermotropic response. However as membranes they do not have the mechanical properties to be applicable in industry. Therefore these hydrogels have been grafted to polyvinylidinedifluoride (PVDF) membranes using radiation. Both UV and gamma irradiation were used. In the first method the PVDF membranes were first hydroxylated by immersion in a aqueous solution of potassium peroxydisulfate (10% w/v), with nitrogen purging for two hours at 80 deg C. This was followed by immersion in an aqueous solution of riboflavine (4mg/L) and monomer (10% v/v), degassing with nitrogen and irradiation under a Mercury UV light (wavelength 240 nm) at room temperature for 15 minutes. Membranes were washed by soxhlet extraction in distilled water and oven dried. The second method of grafting hydrogels to membranes involved immersing the membrane in 10 mL of distilled water containing monomer and CuSO 4 to prevent homopolymerisation. The solution was degassed with N 2 for 3 minutes then irradiated under nitrogen using a 60 Co source for various time periods. The effect of varying monomer and CuSO 4 concentration as well as dose rate and dose were studied. Membranes were rinsed in distilled water for 24 hours and dried in an oven before characterisation. Grafting was characterised by mass change (Mettler AC 100 balance), XPS (PHI Model 560 XPS/SAM/SIMA1 multitechnique surface analysis system), SEM (Hitachi S-900 Field Emission SEM) and FTIR-ATR (Perkn Elmer System 2000 FTIR with MIRMCT detector)

  5. Membranes, methods of making membranes, and methods of separating gases using membranes

    Science.gov (United States)

    Ho, W. S. Winston

    2012-10-02

    Membranes, methods of making membranes, and methods of separating gases using membranes are provided. The membranes can include at least one hydrophilic polymer, at least one cross-linking agent, at least one base, and at least one amino compound. The methods of separating gases using membranes can include contacting a gas stream containing at least one of CO.sub.2, H.sub.2S, and HCl with one side of a nonporous and at least one of CO.sub.2, H.sub.2S, and HCl selectively permeable membrane such that at least one of CO.sub.2, H.sub.2S, and HCl is selectively transported through the membrane.

  6. Elementary Analysis of Petroleum Distillates by Gc-Aed: Validation and Application to the Calculation of Distillation Profile Properties

    Directory of Open Access Journals (Sweden)

    Baco F.

    1999-07-01

    Full Text Available This article describes the development of elementary analysis in the distillation profile of petroleum cuts by gas phase chromatography-atomic emission detection (GC-AED coupling and shows the application perspectives to characterisation of middle distillates of a piece of information unheard of until now on a routine basis. The performances of the analytical assembly used have been studied for carbon, hydrogen, sulphur and nitrogen analysis. Simulated distillation, a gas phase chromatography analysis which enables determining the weight percentage of distilled matter in relation to the boiling point of petroleum cuts, has been adapted to GC-AED coupling. We have developed a method giving access to three types of information: global elementary composition, simulated distillation and elementary composition in distillation profile, i. e. by fraction (% of the distilled product. The analysis of the atmospheric distillates has been assessed in terms of precision and bias for these various types of information. The validation was carried out notably by comparison with the results obtained using reference analytical methods, on preparative distillation cuts of representative samples. The application of GC-AED to characterisation of distillates is discussed, in particular for classification purposes and for predicting petroleum properties in the distillation profile. The cetane number of gas oils was taken as an example to illustrate the latter application.

  7. Surface Functionalization of Polyethersulfone Membrane with Quaternary Ammonium Salts for Contact-Active Antibacterial and Anti-Biofouling Properties

    Directory of Open Access Journals (Sweden)

    Xiao Hu

    2016-05-01

    Full Text Available Biofilm is a significant cause for membrane fouling. Antibacterial-coated surfaces can inhibit biofilm formation by killing bacteria. In this study, polyethersulfone (PES microfiltration membrane was photografted by four antibiotic quaternary ammonium compounds (QACs separately, which were synthesized from dimethylaminoethyl methacrylate (DMAEMA by quaternization with butyl bromide (BB, octyl bromide (OB, dodecyl bromide (DB, or hexadecyl bromide (HB. XPS, ATR-FTIR, and SEM were used to confirm the surfaces’ composition and morphology. After modification, the pores on PES-g-DMAEMA-BB and PES-g-DMAEMA-OB were blocked, while PES-g-DMAEMA-DB and PES-g-DMAEMA-HB were retained. We supposed that DMAEMA-BB and DMAEMA-OB aggregated on the membrane surface due to the activities of intermolecular or intramolecular hydrogen bonds. Bacteria testing found the antibacterial activities of the membranes increased with the length of the substituted alkyl chain. Correspondingly, little bacteria were observed on PES-g-DMAEMA-DB and PES-g-DMAEMA-HB by SEM. The antifouling properties were investigated by filtration of a solution of Escherichia coli. Compared with the initial membrane, PES-g-DMAEMA-DB and PES-g-DMAEMA-HB showed excellent anti-biofouling performance with higher relative flux recovery (RFR of 88.3% and 92.7%, respectively. Thus, surface functionalization of the PES membrane with QACs can prevent bacteria adhesion and improve the anti-biofouling activity by the contact-active antibacterial property.

  8. Distilling shale and the like

    Energy Technology Data Exchange (ETDEWEB)

    Gee, H T.P.

    1922-02-23

    In distilling shale or like bituminous fuels by internal heating with hot gas obtained by the gasifying of the shale residues with air or steam or a mixture of these, the amount and temperature of the gaseous distilling medium is regulated between the gasifying and the distilling chambers, by the introduction of cold gas or air.

  9. Distillation with labelled transition systems

    DEFF Research Database (Denmark)

    Hamilton, Geoffrey William; Jones, Neil

    2012-01-01

    In this paper, we provide an improved basis for the " distillation" program transformation. It is known that superlinear speedups can be obtained using distillation, but cannot be obtained by other earlier automatic program transformation techniques such as deforestation, positive supercompilation...... and partial evaluation. We give distillation an improved semantic basis, and explain how superlinear speedups can occur....

  10. Polymeric Gas-Separation Membranes for Petroleum Refining

    Directory of Open Access Journals (Sweden)

    Yousef Alqaheem

    2017-01-01

    Full Text Available Polymeric gas-separation membranes were commercialized 30 years ago. The interest on these systems is increasing because of the simplicity of concept and low-energy consumption. In the refinery, gas separation is needed in many processes such as natural gas treatment, carbon dioxide capture, hydrogen purification, and hydrocarbons separations. In these processes, the membranes have proven to be a potential candidate to replace the current conventional methods of amine scrubbing, pressure swing adsorption, and cryogenic distillation. In this paper, applications of polymeric membranes in the refinery are discussed by reviewing current materials and commercialized units. Economical evaluation of these membranes in comparison to traditional processes is also indicated.

  11. Distilling bituminous materials

    Energy Technology Data Exchange (ETDEWEB)

    Forrest, C N; Hayden, H P

    1926-12-28

    Bituminous materials such as heavy asphaltic residues from petroleum distillation or natural bitumens such as gilsonite, grahamite, etc. are distilled in presence of a carrier consisting of pieces of inert refractory material and by the heat generated by combustion of the coke which remains on the carrier after distillation. A vertical cylindrical retort, in which a wood and coal fire is first made, is charged with an inert refractory substance such as pumice stone, broken firebrick, burnt fire clay, carborundum, ash, etc. mixed with a bituminous substance, which, if fusible, may be melted and added in a rotary drum. The mixture passes downwards through the retort, first through regions in which the hydrocarbons are distilled and cracked and then through a region in which the remaining carbon is burnt by a limited supply of air and steam admitted through a grate. The inert material is discharged through a water seal and used again. Vapors, withdrawn from the retort though an outlet, pass through a heat intercharger and separator and are treated with a spray of sulfuric acid to separate ammonia in a scrubber, with water sprays to condense oil in scrubbers, and with oil in a scrubber.

  12. Innovative Design of Solar-Powered Desalination (SPD System using Vacuum-Multi Effect Membrane Distillation (V-MEMD Process

    Directory of Open Access Journals (Sweden)

    Chafidz Achmad

    2018-01-01

    Full Text Available This research focused on the development of an innovative design of solar-powered desalination (SPD system which was expected to solve the water and energy problem simultaneously. We have developed a portable and hybrid solar-powered desalination (SPD system for producing potable water from saline water. It is a self-contained and integrated system which combines solar-thermal collector and solar-photovoltaic for its operation, and thus the system can operate to produce water by only using solar energy. Therefore, the system is highly suitable to be implemented in remote arid and coastal areas without infrastructures or connection to the grid (water and power, but blessed with abundant solar irradiation, like in Saudi Arabia. A Memsys Vacuum Multi-Effect Membrane Distillation (V-MEMD unit was used as the core of the SPD system. A heat pump was also integrated into the SPD system for energy recovery and to improve the performance of the system. The system could be considered as sustainable and “green” desalination technology, which will be very useful for the Kingdom of Saudi Arabia. To study the performance of the system, small-scale tests have been carried out at the Engineering College - King Saud University, Saudi Arabia. Based on the experimental results, the system has run successfully by only utilizing solar energy.

  13. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Young, W

    1877-03-29

    The method consists in agitating or circulating the distillation products inside the retort by means of jets of gas, steam, or vapor, or by means of reciprocating pistons; condensing certain of the heavy hydrocarbons; sealing or luting the doors of retorts or distilling-vessels; and conducting the distillation for the manufacture of oil so that the charging or discharging doors may be fitted with self-sealing lids. Several arrangements are shown and described; a single horizontal retort is divided into two compartments by a perforated plate which supports the coal, shale, or other bituminous substance, beneath which a piston is reciprocated or a jet of steam, gas, or vapor injected; a vertical retort is fitted with a central tube into which steam, gas, or vapor is injected, or it may be divided into two compartments and the jet injected into one of these; a pair of vertical retorts are connected by a horizontal passage at the top and bottom, and into the upper one steam, gas, or vapor is injected, or the lower one is fitted with a piston.

  14. Evaluation of chemical composition of defect wine distillates

    OpenAIRE

    Mihaljević Žulj, Marin; Posavec, Barbara; Škvorc, Melanija; Tupajić, Pavica

    2016-01-01

    The aim of this study was to evaluate the chemical composition of the distillate obtained from wine with off-flavour. The chemical composition of wine distillates obtained by distillation of Chardonnay wine with oxidation off-flavour was investigated. Distillation of wine was carried out using a simple distillation pot still by double distillation and separation the different portion of the first fraction. Volatile compounds of wine and wine distillates (acetaldehyde, ethyl acetate, methanol ...

  15. Distilling hydrocarbons, etc

    Energy Technology Data Exchange (ETDEWEB)

    Turner, C

    1917-11-23

    In the fractional or destructive distillation of hydrocarbon oils or other liquids, the pressure in the still is raised and lowered alternately. The still is closed to raise the pressure, and is opened to lower the pressure rapidly solely by expansion of the vapors. The operation is effected without intermittent cooling, except such as may occur during the lowering of the pressure. In distilling hydrocarbon oil, pressure steam is blown into the oil until the pressure reaches 5 lb/in./sup 2/. The vapor outlet is then opened until the pressure falls to 2 lb/in./sup 2/, whereupon the vapor outlet is closed and steam is again admitted. The operation is continued until the steam, which is of 20 lb pressure, no longer effects distillation; after this stage, superheated steam is used.

  16. Low Temperature Geothermal Resource Assessment for Membrane Distillation Desalination in the United States: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Akar, Sertac; Turchi, Craig

    2016-10-01

    Substantial drought and declines in potable groundwater in the United States over the last decade has increased the demand for fresh water. Desalination of saline water such as brackish surface or groundwater, seawater, brines co-produced from oil and gas operations, industrial wastewater, blow-down water from power plant cooling towers, and agriculture drainage water can reduce the volume of water that requires disposal while providing a source of high-quality fresh water for industrial or commercial use. Membrane distillation (MD) is a developing technology that uses low-temperature thermal energy for desalination. Geothermal heat can be an ideal thermal-energy source for MD desalination technology, with a target range of $1/m3 to $2/m3 for desalinated water depending on the cost of heat. Three different cases were analyzed to estimate levelized cost of heat (LCOH) for integration of MD desalination technology with low-grade geothermal heat: (1) residual heat from injection brine at a geothermal power plant, (2) heat from existing underutilized low-temperature wells, and (3) drilling new wells for low-temperature resources. The Central and Western United States have important low-temperature (<90 degrees C) geothermal resource potential with wide geographic distribution, but these resources are highly underutilized because they are inefficient for power production. According to the USGS, there are 1,075 identified low temperature hydrothermal systems, 55 low temperature sedimentary systems and 248 identified medium to high temperature geothermal systems in the United States. The estimated total beneficial heat potential from identified low temperature hydrothermal geothermal systems and residual beneficial heat from medium to high temperature systems is estimated as 36,300 MWth, which could theoretically produce 1.4 to 7 million m3/day of potable water, depending on desalination efficiency.

  17. Super-hydrophobic self-cleaning bead-like SiO2@PTFE nanofiber membranes for waterproof-breathable applications

    Science.gov (United States)

    Liang, Yueyao; Ju, Jingge; Deng, Nanping; Zhou, Xinghai; Yan, Jing; Kang, Weimin; Cheng, Bowen

    2018-06-01

    Superhydrophobic waterproof-breathable membranes, which possess a huge superiority in multi-functional applications including self-cleaning, anti-icing, anticorrosion and protective clothing, have aroused considerable attention owing to their excellent performance. Herein, the robust superhydrophobic microporous fibrous membranes were efficiently prepared via a facile and environmental-friendly electro-blown spinning (EBS) technique followed by calcination. Compared with hydrophobic pure PTFE fibrous membranes, the bead-like SiO2@PTFE nanofiber membranes (BLNFMs) exhibited superhydrophobic surface with the advancing water angle (θadv) and the water contact angle (WCA) up to 161° and 155°, respectively. The SiO2 nanoparticles were introduced as fillers which can alter the pore structure and form the multilevel rough surface. The BLNFMs could maintain superhydrophobic surface even after abrasion for 30 times or exposing to a strong corrosive solution with PH from 0 to 12 for 24 h. Besides, the BLNFMs were endowed with the modest vapor permeability (9.7 kg·m-2·d-1) and air permeability (7.2 mm·s-1) when the concentration of SiO2 nanoparticles reached to 7.3 wt%. In addition, a potential relationship among θadv, maximum pore size (dmax) and breathability (effective breathing area) was proposed in order to design the waterproof-breathable membranes with excellent properties. Furthermore, the superhydrophobic membranes with durable self-cleaning property provided the advantages of potential applications in the fields of membrane distillation, versatile protective clothing, etc.

  18. Organic fluid permeation through fluoropolymer membranes

    Science.gov (United States)

    Nemser, Stuart M.; Kosaraju, Praveen; Bowser, John

    2015-07-14

    Separation of the components of liquid mixtures is achieved by contacting a liquid mixture with a nonporous membrane having a fluoropolymer selectively permeable layer and imposing a pressure gradient across the membrane from feed side to permeate side. Unusually high transmembrane flux is obtained when the membrane is subjected to one or more process conditions prior to separation. These include (a) leaving some residual amount of membrane casting solvent in the membrane, and (b) contacting the membrane with a component of the mixture to be separated for a duration effective to saturate the membrane with the component.

  19. 27 CFR 19.322 - Distillates containing extraneous substances.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distillates containing... Distillates containing extraneous substances. (a) Use in production. Distillates containing substantial... produced. Distillates removed from the distilling system under the provisions of this paragraph shall be...

  20. Improvement of solar ethanol distillation using ultrasonic waves

    Directory of Open Access Journals (Sweden)

    Jaruwat Jareanjit

    2016-08-01

    Full Text Available This report presents a study on the use of ultrasonic waves in solar ethanol distillation to investigate the performance of ultrasonic waves at a frequency of 30 kHz and at 100 Watts that were installed in the inlet area of a 10-litre distillation tank. Based on the non-continuous distillation process (batch distillation, the experiment demonstrated that using ultrasonic waves in solar ethanol distillation caused the average concentration of hourly distilled ethanol to be higher than that of a normal system (solar ethanol distillation without ultrasonic wave at the same or higher distillation rate and hourly distillation volume. The ultrasonic wave was able to enhance the separation of ethanol from the solution (water-ethanol mixture through solar distillation. The amount of pure ethanol product from each distilled batch was clearly larger than the amount of product obtained from a normal system when the initial concentration of ethanol was lower than 50%v/v (% by volume, where an average of approximately 40% and 20% are obtained for an initial ethanol concentration of 10%v/v and 30%v/v, respectively. Furthermore, the distillation rate varied based on the solar radiation value.

  1. 40 CFR 1065.703 - Distillate diesel fuel.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Distillate diesel fuel. 1065.703... Standards § 1065.703 Distillate diesel fuel. (a) Distillate diesel fuels for testing must be clean and... distillate diesel fuels: (1) Cetane improver. (2) Metal deactivator. (3) Antioxidant, dehazer. (4) Rust...

  2. Method of distillation of alum shale

    Energy Technology Data Exchange (ETDEWEB)

    Hultman, G H

    1920-02-03

    A method is given of distilling alum shale by means of preheated gases obtained from the process of distillation in which the gases are circulating within a system consisting of the retort, the condensation apparatus, and generator, each separate. It is characterized by leading the gases produced during the distillation through a condensation apparatus for separation of the condensable products, such as oil, benzene, ammonia, and sulfur, and the noncondensable gases are conveyed through one or more heated generators that have been charged with residue from the process of distillation (any superfluous amount of gas formed during the process being released). The heated gases are thereupon passed to the retort for completion of the distillation process.

  3. Efficient ethanol recovery from yeast fermentation broth with integrated distillation-membrane process

    Science.gov (United States)

    A hybrid process integrating vapor stripping with vapor compression and vapor permeation membrane separation, termed Membrane Assisted Vapor Stripping (MAVS), was evaluated for recovery and dehydration of ethanol from aqueous solution as an alternative to conventional distillatio...

  4. PDMS/PVDF hybrid electrospun membrane with superhydrophobic property and drop impact dynamics for dyeing wastewater treatment using membrane distillation

    KAUST Repository

    An, Alicia Kyoungjin; Guo, Jiaxin; Lee, Eui-Jong; Jeong, Sanghyun; Zhao, Yanhua; Wang, Zuankai; Leiknes, TorOve

    2016-01-01

    .4°) and roughness (Ra = 1,285mm). The zeta potential of E-PDMS membrane surface showed a higher negative value than that of a commercial PVDF (C-PVDF) membrane. These properties of E-PDMS membrane provided an antifouling in treating of differently-charged dyes

  5. Complete nutrient recovery from source-separated urine by nitrification and distillation.

    Science.gov (United States)

    Udert, K M; Wächter, M

    2012-02-01

    In this study we present a method to recover all nutrients from source-separated urine in a dry solid by combining biological nitrification with distillation. In a first process step, a membrane-aerated biofilm reactor was operated stably for more than 12 months, producing a nutrient solution with a pH between 6.2 and 7.0 (depending on the pH set-point), and an ammonium to nitrate ratio between 0.87 and 1.15 gN gN(-1). The maximum nitrification rate was 1.8 ± 0.3 gN m(-2) d(-1). Process stability was achieved by controlling the pH via the influent. In the second process step, real nitrified urine and synthetic solutions were concentrated in lab-scale distillation reactors. All nutrients were recovered in a dry powder except for some ammonia (less than 3% of total nitrogen). We estimate that the primary energy demand for a simple nitrification/distillation process is four to five times higher than removing nitrogen and phosphorus in a conventional wastewater treatment plant and producing the equivalent amount of phosphorus and nitrogen fertilizers. However, the primary energy demand can be reduced to values very close to conventional treatment, if 80% of the water is removed with reverse osmosis and distillation is operated with vapor compression. The ammonium nitrate content of the solid residue is below the limit at which stringent EU safety regulations for fertilizers come into effect; nevertheless, we propose some additional process steps that will increase the thermal stability of the solid product. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Newton, A V

    1856-04-22

    In order to obtain, at the first distillation, from coal, shale, and bituminous substances an oil sufficiently pure for illuminating and other purposes, the material broken into very small pieces and placed on the bottom of the retort, is evenly covered with common sand, about four times greater in weight than the weight of the coal. The coal and sand are then gradually raised to a temperature of 212/sup 0/F. Steam containing carbonaceous impurities first passes to the condenser, and subsequently oil, which rises to the surface of the water in the receiving-vessel. When some bituminous substances are employed, the temperature, after oil ceases to come over, may be gradually raised until the oil produced ceases to be pure. Most kinds of clay and earth, chalk, gypsum, black oxide of manganese, plumbago, or charcoal may be used separately, in combination, or with added chemicals, instead of sand as the medium for filtering the gas or vapor from which the oil is formed. Either the oil obtained by the first distillation or oils obtained by other means may be rectified by distilling with sand.

  7. Performance investigation of a solar-assisted direct contact membrane distillation system

    KAUST Repository

    Kim, Youngdeuk; Thu, Kyaw; Ghaffour, NorEddine; Ng, Kim Choon

    2013-01-01

    that the specific thermal energy consumption decreases significantly by 55% with increased collector area from 1983m2 to 3360m2 whereas the specific electrical energy consumption increases slightly by 16%. © 2012 Elsevier B.V.

  8. Process of distilling heavy hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    1929-12-03

    This invention has for its object the distillation of heavy liquid hydrocarbons for the purpose of obtaining lighter hydrocarbons stable and immediately salable for fuels in combustion motors. The process is distinguished by the fact that the heavy hydrocarbon is distilled by means of heating to a temperature in keeping with the nature of the material to be treated up to 350/sup 0/C under pressure or without pressure the distillation being carried out on catalysts containing successively nickel, copper, and iron (3 parts of nickel, 1 part of copper, and 1 part of iron), the vapors produced by this distillation being exposed in turn to the action of catalysts of the same nature and in the same proportion.

  9. Distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Bell, T

    1863-09-14

    Shales and other bituminous minerals are distilled in horizontal retorts arranged side by side and with furnaces beneath their front ends. The furnace gases pass, preferably through a brickwork grating, into spaces between the retorts and beneath a horizontal partition towards the back ends. They return above the partition to the front of the retorts, and finally enter a horizontal flue leading to a chimney. The front end of each retort is fitted with a hopper for charging and with a door for discharging. The products of distillation pass through perforated partitions inside the retorts and are conveyed away by pipes at the back.

  10. Determination of methanol in Iranian herbal distillates.

    Science.gov (United States)

    Shirani, Kobra; Hassani, Faezeh Vahdati; Azar-Khiavi, Kamal Razavi; Moghaddam, Zohreh Samie; Karimi, Gholamreza

    2016-06-01

    Herbal distillates have been used as beverages, for flavoring, or as phytomedicines in many countries for a long time. Recently, the occurrence of blindness after drinking herbal distillates has created concerns in Iran. The aim of this study was to determine the concentrations of methanol in herbal distillates produced in Iran. Eighty-four most commonly used herbal distillates purchased from herbal distillate factories were analyzed for methanol contents by gas chromatography and flame ionization detection, with ethanol as internal standard. In 15 herbal distillates, the methanol concentration was below the limit of quantitation. The methanol concentrations in all samples ranged from 43 to 277 mg/L. Forty-five samples contained methanol in excess of the Iranian standard. The maximum concentration was found in an herbal distillate of Mentha piperita (factory E) (277±12), and the minimum in a distillate of Carum carvi (factory B) (42.6 ± 0.5). Since the 45 Iranian herbal distillates containing methanol levels were beyond the legal limits according to the Iranian standard, it seems necessary to monitor the amount of methanol and give a warning to watch out for the latent risk problem of methanol uptake, and establish a definitive relationship between the degree of intoxication observed and the accumulation of methanol in the blood.

  11. Tritium Isotope Separation Using Adsorption-Distillation Column

    International Nuclear Information System (INIS)

    Fukada, Satoshi

    2005-01-01

    In order to miniaturize the height of a distillation tower for the detritiation of waste water from fusion reactors, two experiments were conducted: (1) liquid frontal chromatography of tritium water eluting through an adsorption column and (2) water distillation using a column packed with adsorbent particles. The height of the distillation tower depends on the height equivalent to a theoretical plate, HETP, and the equilibrium isotope separation factor, α H-T equi . The adsorption action improved not only HETP but also α H-T equi . Since the adsorption-distillation method proposed here can shorten the tower height with keeping advantages of the distillation, it may bring an excellent way for miniaturizing the distillation tower to detritiate a large amount of waste water from fusion reactors

  12. Polyamide 6/clay membranes: effect of precipitation bath in morphology

    International Nuclear Information System (INIS)

    Ferreira, Rodholfo da S.B.; Pereira, Caio H. do O; Leite, Amanda M.D.; Araujo, Edcleide M.; Lira, Helio L.

    2015-01-01

    Polyamide 6 membranes and their nanocomposites with 5% clay were obtained by the phase inversion method and the precipitation was made in distilled water bath and also in the mixture of solvent and distilled water. The nanocomposites were characterized by XRD and membranes by SEM. By XRD analysis, it was found that the obtained nanocomposite presents a structure probably exfoliated and / or partially exfoliated, it was also possible to observe the presence of two characteristic peaks (α and γ) of the polyamide 6 phases. In the SEM micrographs it was seen that the presence of clay promote alterations in morphology, size and distribution of pores. The presence of acid in the precipitation bath leads to a significant decrease in the filter layer, but also an increase in the quantity of pore size. (author)

  13. Active solar distillation - A detailed review

    Energy Technology Data Exchange (ETDEWEB)

    Sampathkumar, K.; Pitchandi, P. [Department of Mechanical Engineering, Tamilnadu College of Engineering, Coimbatore 641659, Tamilnadu (India); Arjunan, T.V. [Department of Automobile Engineering, PSG College of Technology, Coimbatore 641004, Tamilnadu (India); Senthilkumar, P. [Department of Mechanical Engineering, KSR College of Engineering, Tiruchengode 637215, Tamilnadu (India)

    2010-08-15

    All over the world, access to potable water to the people are narrowing down day by day. Most of the human diseases are due to polluted or non-purified water resources. Even today, under developed countries and developing countries face a huge water scarcity because of unplanned mechanism and pollution created by manmade activities. Water purification without affecting the ecosystem is the need of the hour. In this context, many conventional and non-conventional techniques have been developed for purification of saline water. Among these, solar distillation proves to be both economical and eco-friendly technique particularly in rural areas. Many active distillation systems have been developed to overcome the problem of lower distillate output in passive solar stills. This article provides a detailed review of different studies on active solar distillation system over the years. Thermal modelling was done for various types of active single slope solar distillation system. This review would also throw light on the scope for further research and recommendations in active solar distillation system. (author)

  14. An adhesion-based method for plasma membrane isolation: evaluating cholesterol extraction from cells and their membranes.

    Science.gov (United States)

    Bezrukov, Ludmila; Blank, Paul S; Polozov, Ivan V; Zimmerberg, Joshua

    2009-11-15

    A method to isolate large quantities of directly accessible plasma membrane from attached cells is presented. The method is based on the adhesion of cells to an adsorbed layer of polylysine on glass plates, followed by hypotonic lysis with ice-cold distilled water and subsequent washing steps. Optimal conditions for coating glass plates and time for cell attachment were established. No additional chemical or mechanical treatments were used. Contamination of the isolated plasma membrane by cell organelles was less than 5%. The method uses inexpensive, commercially available polylysine and reusable glass plates. Plasma membrane preparations can be made in 15 min. Using this method, we determined that methyl-beta-cyclodextrin differentially extracts cholesterol from fibroblast cells and their plasma membranes and that these differences are temperature dependent. Determination of the cholesterol/phospholipid ratio from intact cells does not reflect methyl-beta-cyclodextrin plasma membrane extraction properties.

  15. THE EFFECT OF DISTILLATE STORING DISTILLED FROM FRUCTOSE SYRUPS TOWARD ITS ACETALDEHYDE CONCENTRATION MEASURED BY GAS CHROMATOGRAPHY

    Directory of Open Access Journals (Sweden)

    Maria Monica Sianita Basukiwardojo

    2010-06-01

    Full Text Available Acetaldehyde is a compound of aldehyde group that is very volatile and toxic. This compound can be found in fructose syrups used in carbonate beverages. The syrups had been distilled then analysed using gas chromatography. The concentration of acetaldehyde was 289.78 g/g in the distillates kept for one week, 295.30 g/g in those kept for two weeks, 429.45 g/g in those kept for three weeks, and 449.38 g/g in those kept for four weeks. The optimum column temperature was programmed with initial temperature of 40 oC held on for four minutes, then increasing by 40 oC/minute to 200 oC. It can be concluded that the longer the distillates have been kept, the greater the concentration of acetaldehyde in the distillates. A further research to investigate the present of microbe in the distillates and the effect of pH should be conducted   Keywords: acetaldehyde, fructose syrup, distillates, gas chromatography.

  16. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Neilson, A; Renfrewshire, I; Black, W

    1889-06-14

    The invention relates to a method of, and apparatus for, distilling shale, coal, or other oil or tar-yielding minerals, to obtain gases, liquids, or other products. The distillation is effected in vertical retorts by the combustion of the partially spent material in the lower part of the retorts, to which steam and air are admitted. The retorts are built of firebrick, and provided with iron casings. They are fed through hoppers and discharged through the openings. The discharging is facilitated by a cone, or its equivalent, in the base of each retort. Steam and air are admitted through the pipes. The interior may be viewed through holes. The products are taken off from the space around the hopper.

  17. Microbubble Distillation for Ethanol-Water Separation

    Directory of Open Access Journals (Sweden)

    Atheer Al-yaqoobi

    2016-01-01

    Full Text Available In the current study, a novel approach for separating ethanol-water mixture by microbubble distillation technology was investigated. Traditional distillation processes require large amounts of energy to raise the liquid to its boiling point to effect removal of volatile components. The concept of microbubble distillation by comparison is to heat the gas phase rather than the liquid phase to achieve separation. The removal of ethanol from the thermally sensitive fermentation broths was taken as a case of study. Consequently the results were then compared with those which could be obtained under equilibrium conditions expected in an “ideal” distillation unit. Microbubble distillation has achieved vapour compositions higher than that which could be obtained under traditional equilibrium conditions. The separation was achieved at liquid temperature significantly less than the boiling point of the mixture. In addition, it was observed that the separation efficiency of the microbubble distillation could be increased by raising the injected air temperature, while the temperature of the liquid mixture increased only moderately. The separation efficiency of microbubble distillation was compared with that of pervaporation for the recovery of bioethanol from the thermally sensitive fermentation broths. The technology could be controlled to give high separation and energy efficiency. This could contribute to improving commercial viability of biofuel production and other coproducts of biorefinery processing.

  18. Investigation related to hydrogen isotopes separation by cryogenic distillation

    International Nuclear Information System (INIS)

    Bornea, A.; Zamfirache, M.; Stefanescu, I.; Preda, A.; Balteanu, O.; Stefan, I.

    2008-01-01

    Research conducted in the last fifty years has shown that one of the most efficient techniques of removing tritium from the heavy water used as moderator and coolant in CANDU reactors (as that operated at Cernavoda (Romania)) is hydrogen cryogenic distillation. Designing and implementing the concept of cryogenic distillation columns require experiments to be conducted as well as computer simulations. Particularly, computer simulations are of great importance when designing and evaluating the performances of a column or a series of columns. Experimental data collected from laboratory work will be used as input for computer simulations run at larger scale (for The Pilot Plant for Tritium and Deuterium Separation) in order to increase the confidence in the simulated results. Studies carried out were focused on the following: - Quantitative analyses of important parameters such as the number of theoretical plates, inlet area, reflux flow, flow-rates extraction, working pressure, etc. - Columns connected in series in such a way to fulfil the separation requirements. Experiments were carried out on a laboratory-scale installation to investigate the performance of contact elements with continuous packing. The packing was manufactured in our institute. (authors)

  19. Efficiency of fermionic quantum distillation

    Energy Technology Data Exchange (ETDEWEB)

    Herbrych, Jacek W. [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Feiguin, Adrian E. [Northeastern Univ., Boston, MA (United States); Dagotto, Elbio R. [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Heidrich-Meisner, F. [Ludwig-Maximilians-Univ. Munchen, Munchen (Germany)

    2017-09-13

    Here, we present a time-dependent density-matrix renormalization group investigation of the quantum distillation process within the Fermi-Hubbard model on a quasi-one-dimensional ladder geometry. The term distillation refers to the dynamical, spatial separation of singlons and doublons in the sudden expansion of interacting particles in an optical lattice, i.e., the release of a cloud of atoms from a trapping potential. Remarkably, quantum distillation can lead to a contraction of the doublon cloud, resulting in an increased density of the doublons in the core region compared to the initial state. As a main result, we show that this phenomenon is not limited to chains that were previously studied. Interestingly, there are additional dynamical processes on the two-leg ladder such as density oscillations and self-trapping of defects that lead to a less efficient distillation process. An investigation of the time evolution starting from product states provides an explanation for this behavior. Initial product states are also considered since in optical lattice experiments, such states are often used as the initial setup. We propose configurations that lead to a fast and efficient quantum distillation.

  20. Distilling coal, etc

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, J

    1917-12-21

    Coals of various kinds such as shales, bitumens, and oil sand, peat, etc. are distilled at 350 to 450/sup 0/C and in the presence of vapors and gases obtained by cracking hydrocarbon oils, or the gases obtained by separating the condensable hydrocarbons therefrom, and, if desired, with the addition of superheated steam. The hydrocarbons are properly cracked by passing through molten lead as described in Specification 116,304. According to the Provisional Specification, superheated steam alone may be used to effect the distillation.

  1. Refining shale-oil distillates

    Energy Technology Data Exchange (ETDEWEB)

    Altpeter, J

    1952-03-17

    A process is described for refining distillates from shale oil, brown coal, tar, and other tar products by extraction with selective solvents, such as lower alcohols, halogen-hydrins, dichlorodiethyl ether, liquid sulfur dioxide, and so forth, as well as treating with alkali solution, characterized in that the distillate is first treated with completely or almost completely recovered phenol or cresotate solution, the oil is separated from the phenolate with solvent, for example concentrated or adjusted to a determined water content of lower alcohol, furfural, halogen-hydrin, dichlorodiethyl ether, liquid sulfur dioxide, or the like, extracted, and the raffinate separated from the extract layer, if necessary after distillation or washing out of solvent, and freeing with alkali solution from residual phenol or creosol.

  2. Preparation of Water-Selective Polybutadiene Membranes and Their Use in Drying Alcohols by Pervaporation and Vapor Permeation Technologies

    Science.gov (United States)

    Separating azeotrope-forming solvent-water mixtures by conventional distillation poses technical, economic, and environmental challenges. Membrane technology using water-permselective membranes provides an efficient alternative for water removal from solvents. We present here a n...

  3. Removal of VOCs from groundwater using membrane-assisted solvent extraction

    International Nuclear Information System (INIS)

    Hutter, J.C.; Vandegrift, G.F.; Nunez, L.; Redfield, D.H.

    1992-01-01

    A membrane-assisted solvent extraction (MASX) system coupled to a membrane-assisted distillation stripping (MADS) system for use in decontaminating groundwater is discussed. Volatile organic compounds (VOCs) are extracted in the MASX using a sunflower oil solvent. In the MADS, VOCs are stripped from the sunflower oil, and the oil is recycled to the MASX. Thermodynamic data for the sunflower oil-water-VOCs system were experimentally collected. Published membrane-mass transfer results along with these data were used to design the MASX and MADS modules

  4. Contact activation: a revision.

    Science.gov (United States)

    Schmaier, A H

    1997-07-01

    In conclusion, a revised view of the contact system has been presented. This system has little to do with the initiation of hemostasis. Like lupus anticoagulants, deficiencies of contact proteins give prolonged APTTs but may be risk factors for thrombosis. BK from kininogens is a potent modulator of vascular biology inducing vasodilation, tissue plasminogen activator release, and prostacyclin liberation. Kininogens, themselves, are selective inhibitors of alpha-thrombin-induced platelet activation preventing alpha-thrombin from cleaving the cloned thrombin receptor after arginine41. Kininogens' alpha-thrombin inhibitory activity exists in intact kininogens, BK, and all of BK's breakdown products. HK also is the pivotal protein for contact protein assembly on endothelium. It is the receptor for prekallikrein which when bound to HK becomes activated to kallikrein by an endothelial cell enzyme system independent of activated forms of plasma factor XII. Prekallikrein activation on endothelial cells results in kinetically favorable single chain urokinase and plasminogen activation. Thus the "physiologic, negatively charged surface" for contact system activation is really the assembly of these proteins on cell membranes and activation by membrane-associated enzymes.

  5. Distilling carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Trumble, M J

    1925-06-29

    Carbonaceous materials such as coal, oil shale, peat, or wood are destructively distilled while being subjected to the action of superheated steam and hydrogen, the latter being provided by dissociating a part of the superheated steam. The materials are charged into a retort heated by a burner and superheated steam and hydrogen are passed in by a pipe and nozzles. The distillates enter a dust extractor through openings and escape through openings shielded by cones into an outlet pipe leading to condensers. The dust which settles in the bottom of the apparatus is periodically removed.

  6. Influence of phosphate buffer and proteins on the potentiometric response of a polymeric membrane-based solid-contact Pb(II) ion-selective electrode

    DEFF Research Database (Denmark)

    Joon, Narender Kumar; He, Ning; Wagner, Michal

    2017-01-01

    In this work, the influence of phosphate buffer and proteins on the potentiometric response of a polymeric membrane-based solid-contact Pb2+-selective electrode (Pb2+-ISE) was studied. The effects of bovine serum albumin (BSA) adsorption at the surface of the ion-selective membrane combined...... ions studied (Cu2+, Cd2+). Conditioning of the Pb2+-ISE in 0.01 mol dm–3 PBS resulted in a super-Nernstian response which was related to fixation/extraction of Pb2+ in the ion-selective membrane via precipitation of Pb3(PO4)2 by PO43– anions present in PBS. By conditioning of the Pb2+-ISE in 0.01 mol...

  7. Method of distilling organic materials

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, E G.T.

    1921-11-11

    In the distillation of organic materials, by means of coursing heated gases through the distillation chamber, that can be heated by other means also, a method is given by which the hot gases coming from the distillation chamber are cooled in one or more heat-absorbent devices (for example, in spray coolers, condensers and/or water). The greater part of the products or constituents condensable at ordinary temperature are separated from the vapors and gases, and thereafter the gases should be passed through the distillation chamber after the necessary additional heating in special heaters, as one or more heat producers, suitably of the same construction as the heat absorbers, for heating and saturation with steam by means of warm condensate and/or water obtained fully or partly from the heat absorbers, possibly after separation of tar or oil from them. The patent has 11 other claims.

  8. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Urquhart, D

    1882-08-19

    Manufacture of ammonia and purification of shale oils are described. In the distillation of shales, increase of ammonia is obtained and the oils are less contaminated by sulfur, by mixing a small proportion, about two to three percent, of lime or slaked line with the shale. The same process is used with other carbonaceous substances containing nitrogen, such as peat, coal, or the like; but a smaller proportion of lime is used than in the former case, and the lime is slaked with caustic soda solution. When slack or waste coal or other carbonaceous substances are distilled by heated air or gases arising from imperfect combustion, as in furnaces on the gas producer principle, slaked lime is added to the slack or other material.

  9. Distilling oils

    Energy Technology Data Exchange (ETDEWEB)

    Leffer, L G

    1912-01-29

    In a process for converting heavy hydrocarbons, such as petroleum or shale oil, into light hydrocarbons by distilling under the pressure of an inert gas, the operation is conducted at a temperature not exceeding 410/sup 0/C and under an accurately regulated pressure, the gas being circulated through the still and the condenser by means of a pump. The oil in the still may be agitated by stirring vanes or by blowing the gas through it. Hydrogen, nitrogen, carbon dioxide, methane, or gases generated in the distillation may be used as pressure media; the gas is heated before its admission to the still. A pressure of from 11 to 12 atmospheres is used in treating gas oil. Specification 10,277/89 is referred to.

  10. Solar power water distillation unit

    International Nuclear Information System (INIS)

    Hameed, Kamran; Khan, Muhammad Muzammil; Ateeq, Ijlal Shahrukh; Omair, Syed Muhammad; Ahmer, Muhammad; Wajid, Abdul

    2013-01-01

    Clean drinking water is the basic necessity for every human being, but about 1.1 billion people in the world lacked proper drinking water. There are many different types of water purification processes such as filtration, reverse osmosis, ultraviolet radiation, carbon absorption, but the most reliable processes are distillation and boiling. Water purification, such as distillation, is especially important in regions where water resources or tap water is not suitable for ingesting without boiling or chemical treatment. In design project It treats the water by combining different methods such as Filtration, Distillation and a technique called concentrated solar power (CSP). Distillation is literally the method seen in nature, whereby: the sun heats the water on the earth's surface, the water is turned into a vapor (evaporation) and rises, leaving contaminants behind, to form clouds. As the upper atmosphere drops in temperature the vapors cool and convert back to water to form water. In this project distillation is achieved by using a parabolic mirror which boils water at high temperature. Filtration is done by sand filter and carbon filter. First sand filter catches the sand particles and the carbon filter which has granules of active carbon is used to remove odor dissolved gases from water. This is the Pre-treatment of water. The filtered water is then collected in a water container at a focus of parabolic mirror where distillation process is done. Another important feature of designed project is the solar tracking of a parabolic mirror which increases the efficiency of a parabolic mirror [1],[2].

  11. Systematic mapping of contact sites reveals tethers and a function for the peroxisome-mitochondria contact

    NARCIS (Netherlands)

    Shai, Nadav; Yifrach, Eden; van Roermund, Carlo W T; Cohen, Nir; Bibi, Chen; IJlst, Lodewijk; Cavellini, Laetitia; Meurisse, Julie; Schuster, Ramona; Zada, Lior; Mari, Muriel C; Reggiori, Fulvio M; Hughes, Adam L; Escobar-Henriques, Mafalda; Cohen, Mickael M; Waterham, Hans R; Wanders, Ronald J A; Schuldiner, Maya; Zalckvar, Einat

    2018-01-01

    The understanding that organelles are not floating in the cytosol, but rather held in an organized yet dynamic interplay through membrane contact sites, is altering the way we grasp cell biological phenomena. However, we still have not identified the entire repertoire of contact sites, their

  12. A totally heat-integrated distillation column (THIDiC) - the effect of feed pre-heating by distillate

    Energy Technology Data Exchange (ETDEWEB)

    Huang Kejin [School of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)], E-mail: huangkj@mail.buct.edu.cn; Shan Lan; Zhu Qunxiong [School of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China); Qian Jixin [School of Information Science and Technology, Zhejiang University, Zhejiang 300027 (China)

    2008-06-15

    An ideal heat-integrated distillation column (ideal HIDiC) is characterized by external zero-reflux and zero-reboil ratio operation. Since the distillate is a high-pressure vapor phase flow, it can be used to pre-heat the feed to be separated, thereby giving rise to a totally heat-integrated distillation column (THIDiC). Although the THIDiC is more thermodynamically efficient than the ideal HIDiC, it is found that the heat integration between the distillate and feed turns it into an open-loop integrating process and poses additional difficulties to process operation. Therefore, a careful decision must be made on the selection between the ideal HIDiC and the THIDiC during process development. In this paper, separation of a binary equimolar mixture of benzene and toluene is selected as an illustrative example. Both process design and operability analysis are conducted, with special emphasis focused on the characteristics of feed pre-heating with distillate. The results obtained show deep insight into the design and operation of the THIDiC.

  13. A totally heat-integrated distillation column (THIDiC) - the effect of feed pre-heating by distillate

    International Nuclear Information System (INIS)

    Huang Kejin; Shan Lan; Zhu Qunxiong; Qian Jixin

    2008-01-01

    An ideal heat-integrated distillation column (ideal HIDiC) is characterized by external zero-reflux and zero-reboil ratio operation. Since the distillate is a high-pressure vapor phase flow, it can be used to pre-heat the feed to be separated, thereby giving rise to a totally heat-integrated distillation column (THIDiC). Although the THIDiC is more thermodynamically efficient than the ideal HIDiC, it is found that the heat integration between the distillate and feed turns it into an open-loop integrating process and poses additional difficulties to process operation. Therefore, a careful decision must be made on the selection between the ideal HIDiC and the THIDiC during process development. In this paper, separation of a binary equimolar mixture of benzene and toluene is selected as an illustrative example. Both process design and operability analysis are conducted, with special emphasis focused on the characteristics of feed pre-heating with distillate. The results obtained show deep insight into the design and operation of the THIDiC

  14. Ion-Exchanged SAPO-34 Membranes for Krypton-Xenon Separation: Control of Permeation Properties and Fabrication of Hollow Fiber Membranes.

    Science.gov (United States)

    Kwon, Yeon Hye; Min, Byunghyun; Yang, Shaowei; Koh, Dong-Yeun; Bhave, Ramesh R; Nair, Sankar

    2018-02-21

    Separation of radioisotope 85 Kr from 136 Xe is of importance in used nuclear fuel reprocessing. Membrane separation based on zeolite molecular sieves such as chabazite SAPO-34 is an attractive alternative to energy-intensive cryogenic distillation. We report the synthesis of SAPO-34 membranes with considerably enhanced performance via thickness reduction based upon control of a steam-assisted vapor-solid conversion technique followed by ion exchange with alkali metal cations. The reduction of membrane thickness leads to a large increase in Kr permeance from 7.5 to 26.3 gas permeation units (GPU) with ideal Kr/Xe selectivities >20 at 298 K. Cation-exchanged membranes show large (>50%) increases in selectivity at ambient or slight subambient conditions. The adsorption, diffusion, and permeation characteristics of ion-exchanged SAPO-34 materials and membranes are investigated in detail, with potassium-exchanged SAPO-34 membranes showing particularly attractive performance. We then demonstrate the fabrication of selective SAPO-34 membranes on α-alumina hollow fibers.

  15. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Use of distillates... distillates containing aldehydes. Distillates containing aldehydes may be received on wine premises for use in the fermentation of wine and then returned to the distilled spirits plant from which distillates were...

  16. Three-phase fluidized distillation

    International Nuclear Information System (INIS)

    Ravagnani, T.M.K.; Pereira, J.A.F.R.

    2001-01-01

    Separation efficiency in distillation operations can be improved by modifying the characteristics of the dispersions formed on the trays. The present work reports on the hydrodynamic and mass transfer characteristics of liquid-solid-vapour dispersions formed on sieve trays without downcomers of a distillation column operating under total reflux conditions. Murphree efficiency and the operating limits of distillation using the ethanol-n-butanol system are analyzed for a large range of vapour velocities and liquid mixture compositions, utilising wettable PVC particles and non-wettable silicone, PE, and Teflon((R)) particles. It was verified that wettable particles show a drastic reduction in the upper operating limit of vapour velocity, but this does not occur for non-wettable particles. Tray efficiency can be increased when non-wettable particles are used, mainly for high vapour velocity operations. (author)

  17. 7 CFR 160.8 - Steam distilled wood turpentine.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation from...

  18. Ekstraksi Minyak Atsiri Dari Akar Wangi Menggunakan Metode Steam - Hydro distillation dan Hydro distilation dengan Pemanas Microwave

    Directory of Open Access Journals (Sweden)

    Maulana M Al Hanief

    2013-09-01

    Full Text Available Penelitian ini bertujuan untuk memperoleh minyak atsiri dari akar wangi dengan modifikasi metode steam-hydro distillation dan hydro distillation yaitu menggunakan pemanasan microwave kemudian membandingkan hasilnya dengan penelitian sebelumnya. Modifikasi ini diharapkan lebih efisien dalam masalah lama penyulingan dan kualitas serta kuantitas rendemen minyak yang lebih baik dan banyak. Penelitian ini menggunakan dua metode yaitu steam-hydro distillation dan hydro distillation dengan pemanfaatan gelombang mikro. Bahan baku yang digunakan dalam penelitian adalah akar wangi jenis pulus wangi yang tumbuh di Kabupaten Garut, Jawa Barat. Variabel yang digunakan adalah bahan baku yang dicacah dan bahan baku utuh dengan variasi massa bahan 50 gr, 60, gr, 70 gr, 80 gr, dan 90 gr dengan pelarut air sebanyak 450 ml dalam labau distiller berukuran 1000 ml. Lama penyulingan adalah lima jam dengan pengamatan tiap 30 menit serta daya yang digunakan adalah 400 Watt. Analisa terhadap hasil minyak atsiri yang diperoleh antara lain analisa GC-MS, spesific gravity, indeks bias, dan bilangan asam. Hasil dari penelitian ini dibandingkan dengan hasil penelitian terdahulu yang tidak memanfaatkan gelombang mikro. Dari hasil penelitian diperoleh % rendemen kumulatif, sifat fisik, sifat kimia, dan kandungan komponen minyak dari metode steam-hydro distillation lebih baik dibandingkan metode hydro distillation ditandai dengan kuantitas dan kualitas yang sesuai dengan SNI.  Sementara itu jika dibandingkan dengan metode terdahulu dapat disimpulkan bahwa penggunaan gelombang mikro lebih efisien dalam waktu dan kuantitas serta kualitas minyak yang lebih baik dibandingkan tanpa penggunaan gelombang mikro

  19. Low temperature distillation of coal, shale, etc

    Energy Technology Data Exchange (ETDEWEB)

    1938-08-12

    A process is disclosed for the low temperature distillation of solid carbonaceous fuels, such as coal, lignite, shale or the like, which comprises feeding or supplying the comminuted fuel in the form of a layer of shallow depth to drying and distilling zones in succession moving the fuel forward through the zones, submitting it to progressively increasing nonuniform heating therein by combustion gases supplied to the distillation zone and traveling thence to the drying zone, the gases heating the distillation zone indirectly and the drying zone both indirectly and then directly such that the fuel retains its solid discrete form during substantially the whole of its travel through the drying and distillation zones, subjecting the fuel for a portion of its travel to a zigzag ploughing and propelling movement on a heated sole, and increasing the heating so as to cause fusion of the fuel immediately prior to its discharge from the distillation zone.

  20. 40 CFR 721.9635 - Terpene residue distillates.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Terpene residue distillates. 721.9635... Substances § 721.9635 Terpene residue distillates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as terpene residue distillates (PMN P-96-897...

  1. Dynamic effects of diabatization in distillation columns

    DEFF Research Database (Denmark)

    Bisgaard, Thomas; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2013-01-01

    The dynamic effects of diabatization in distillation columns are investigated in simulation emphasizing the heat-integrated distillation column (HIDiC). A generic, dynamic, first-principle model has been formulated, which is flexible enough to describe various diabatic distillation configurations....... Dynamic Relative Gain Array and Singular Value Analysis have been applied in a comparative study of a conventional distillation column and a HIDiC. The study showed increased input-output coupling due to diabatization. Feasible SISO control structures for the HIDiC were also found and control...

  2. Dynamic Effects of Diabatization in Distillation Columns

    DEFF Research Database (Denmark)

    Bisgaard, Thomas; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2012-01-01

    The dynamic eects of diabatization in distillation columns are investigated in simulation with primary focus on the heat-integrated distillation column (HIDiC). A generic, dynamic, rst-principle model has been formulated, which is exible to describe various diabatic distillation congurations....... Dynamic Relative Gain Array and Singular Value Analysis have been applied in a comparative study of a conventional distillation column and a HIDiC. The study showed increased input-output coupling due to diabatization. Feasible SISO control structures for the HIDiC were also found. Control...

  3. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Cosden, S; Cosden, J S

    1937-09-08

    A means and process are described for the destructive distillation of solid carbonaceous materials in which the process comprises charging the material, in a finely divided condition into a stream of hot combustion gases, and allows the hot gases to act pyrolytically on the organic compounds contained in the material, separating the volatile liberated constituents from residuary constituents. Hot reaction gases are generated by fuel ignition means in a generator and are immediately intermingled with comminuted carbonaceous material from a hopper, in a narrow conduit. The mixture of material and reaction fluid is then passed through an elongated confined path, which is exteriorly heated by the combustion chamber of the furnace, where the destructive distillation is effected. Volatile and solid constituents are separated in the chamber, and the volatile constituents are fractionated and condensed.

  4. Novel process integration for biodiesel blend in membrane reactive divided wall (MRDW column

    Directory of Open Access Journals (Sweden)

    Sakhre Vandana

    2016-03-01

    Full Text Available The paper proposes a novel process integration for biodiesel blend in the Membrane assisted Reactive Divided Wall Distillation (MRDW column. Biodiesel is a green fuel and grade of biodiesel blend is B20 (% which consist of 20% biodiesel and rest 80% commercial diesel. Instead of commercial diesel, Tertiary Amyl Ethyl Ether (TAEE was used as an environment friendly fuel for blending biodiesel. Biodiesel and TAEE were synthesized in a pilot scale reactive distillation column. Dual reactive distillation and MRDW were simulated using aspen plus. B20 (% limit calculation was performed using feed flow rates of both TAEE and biodiesel. MRDW was compared with dual reactive distillation column and it was observed that MRDW is comparatively cost effective and suitable in terms of improved heat integration and flow pattern.

  5. On the Recent Use of Membrane Technology for Olive Mill Wastewater Purification

    Directory of Open Access Journals (Sweden)

    Javier Miguel Ochando-Pulido

    2015-09-01

    Full Text Available Many reclamation treatments as well as integrated processes for the purification of olive mill wastewaters (OMW have already been proposed and developed but not led to completely satisfactory results, principally due to complexity or cost-ineffectiveness. The olive oil industry in its current status, composed of little and dispersed factories, cannot stand such high costs. Moreover, these treatments are not able to abate the high concentration of dissolved inorganic matter present in these highly polluted effluents. In the present work, a review on the actual state of the art concerning the treatment and disposal of OMW by membranes is addressed, comprising microfiltration (MF, ultrafiltration (UF, nanofiltration (NF, and reverse osmosis (RO, as well as membrane bioreactors (MBR and non-conventional membrane processes such as vacuum distillation (VD, osmotic distillation (OD and forward osmosis (FO. Membrane processes are becoming extensively used to replace many conventional processes in the purification of water and groundwater as well as in the reclamation of wastewater streams of very diverse sources, such as those generated by agro-industrial activities. Moreover, a brief insight into inhibition and control of fouling by properly-tailored pretreatment processes upstream the membrane operation and the use of the critical and threshold flux theories is provided.

  6. Multiple-membrane multiple-electrolyte redox flow battery design

    Science.gov (United States)

    Yan, Yushan; Gu, Shuang; Gong, Ke

    2017-05-02

    A redox flow battery is provided. The redox flow battery involves multiple-membrane (at least one cation exchange membrane and at least one anion exchange membrane), multiple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and at least one electrolyte disposed between the two membranes) as the basic characteristic, such as a double-membrane, triple electrolyte (DMTE) configuration or a triple-membrane, quadruple electrolyte (TMQE) configuration. The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte.

  7. Destructive distillation under pressure

    Energy Technology Data Exchange (ETDEWEB)

    1932-09-08

    A process of destructive distillation of distillable carbonaceous material under pressure is described, consisting of regulating the temperature by introducing the carbonaceous materials to a point where the reaction of hydrogenation has begun but has not stopped, by placing it in indirect heat-exchange with a cooling agent at a critical temperature below the reaction temperature, the agent being under pressure and introduced in the liquid state. Water is used as the cooling agent.

  8. Secret key distillation from shielded two-qubit states

    International Nuclear Information System (INIS)

    Bae, Joonwoo

    2010-01-01

    The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.

  9. Double-membrane triple-electrolyte redox flow battery design

    Science.gov (United States)

    Yushan, Yan; Gu, Shuang; Gong, Ke

    2018-03-13

    A redox flow battery is provided having a double-membrane (one cation exchange membrane and one anion exchange membrane), triple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and one electrolyte positioned between and in contact with the two membranes). The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte. This design physically isolates, but ionically connects, the negative electrolyte and positive electrolyte. The physical isolation offers great freedom in choosing redox pairs in the negative electrolyte and positive electrolyte, making high voltage of redox flow batteries possible. The ionic conduction drastically reduces the overall ionic crossover between negative electrolyte and positive one, leading to high columbic efficiency.

  10. 136 Xe enrichment through cryogenic distillation

    Energy Technology Data Exchange (ETDEWEB)

    Back, Henning O.; Bottenus, Daniel R.; Clayton, Christopher K.; Stephenson, David E.; TeGrotenhuis, Ward E.

    2017-09-01

    The next generation of 136Xe neutrinoless double beta decay experiments will require on the order of 5 tons of enriched 136Xe. By estimating the relative volatilities of the xenon isotopes and using standard chemical engineering techniques we explore the feasibility of using cryogenic distillation to produce 5 tons of 80% enriched 136Xe in 5-6 years. With current state-of-the-art distillation column packing materials we can estimate the total height of a traditional cryogenic distillation column. We also, report on how Micro Channel Distillation may reduce the overall size of a distillation system for 136Xe production.

  11. Future perspectives of using hollow fibers as structured packings in light hydrocarbon distillation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Dali [Los Alamos National Laboratory; Orler, Bruce [Los Alamos National Laboratory; Tornga, Stephanie [Los Alamos National Laboratory; Welch, Cindy [Los Alamos National Laboratory

    2011-01-26

    Olefin and paraffin are the largest chemical commodities. Furthermore, they are major building blocks for the petrochemical industry. Each year, petroleum refining, consumes 4,500 TBtu/yr in separation energy, making it one of the most energy-intensive industries in the United States). Just considering liquefied petroleum gas (ethane/propane/butane) and olefins (ethylene and propylene) alone, the distillation energy consumption is about 400 TBtu/yr in the US. Since petroleum distillation is a mature technology, incremental improvements in column/tray design will only provide a few percent improvements in the performance. However, each percent saving in net energy use amounts to savings of 10 TBtu/yr and reduces CO{sub 2} emissions by 0.2 MTon/yr. In practice, distillation columns require 100 to 200 trays to achieve the desired separation. The height of a transfer unit (HTU) of conventional packings is typical in the range of 36-60 inch. Since 2006, we had explored using several non-selective membranes as the structured packings to replace the conventional packing materials used in propane and propylene distillation. We obtained the lowest HTU of < 8 inch for the hollow fiber column, which was >5 times shorter than that of the conventional packing materials. In 2008, we also investigated this type of packing materials in iso-/n-butane distillation. Because of a slightly larger relative volatility of iso-/n-butane than that of propane/propylene, a wider and a more stable operational range was obtained for the iso-/n-butane pair. However, all of the experiments were conducted on a small scale with flowrate of < 25 gram/min. Recently, we demonstrated this technology on a larger scale (<250 gram/min). Within the loading range of F-factor < 2.2 Pa{sup 0.5}, a pressure drop on the vapor side is below 50 mbar/m, which suggests that the pressure drop of hollow fibers packings is not an engineering barrier for the applications in distillations. The thermal stability study

  12. Distillation of shale in situ

    Energy Technology Data Exchange (ETDEWEB)

    de Ganahl, C F

    1922-07-04

    To distill buried shale or other carbon containing compounds in situ, a portion of the shale bed is rendered permeable to gases, and the temperature is raised to the point of distillation. An area in a shale bed is shattered by explosives, so that it is in a relatively finely divided form, and the tunnel is then blocked by a wall, and fuel and air are admitted through pipes until the temperature of the shale is raised to such a point that a portion of the released hydrocarbons will burn. When distillation of the shattered area takes place and the lighter products pass upwardly through uptakes to condensers and scrubbers, liquid oil passes to a tank and gas to a gasometer while heavy unvaporized products in the distillation zone collect in a drain, flow into a sump, and are drawn off through a pipe to a storage tank. In two modifications, methods of working are set out in cases where the shale lies beneath a substantially level surface.

  13. Operation and Design of Diabatic Distillation Processes

    DEFF Research Database (Denmark)

    Bisgaard, Thomas

    Diabatic operation of a distillation column implies that heat is exchanged in one or more stages in the column. The most common way of realising diabatic operation is by internal heat integration resulting in a heat-integrated distillation column (HIDiC). When operating the rectifying section...... at a higher pressure, a driving forcefor transferring heat from the rectifying section to the stripping section is achieved. As a result, the condenser and reboiler duties can be significantly reduced. For two-product distillation, the HIDiC is a favourable alternative to the conventional distillation column....... Energy savings up to 83% are reported for the HIDiC compared to the CDiC, while the reported economical savings are as high as 40%. However, a simpler heat-integrated distillation column configuration exists, which employs compression in order to obtain a direct heat integration between the top vapour...

  14. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Kern, L

    1922-07-21

    In the distillation of shale and similar materials the shale is ground and briquetted and the briquettes are placed in a retort so that air passages are left between them, after which they are uniformly and slowly heated to at least 700/sup 0/C, the air passages facilitating the escape of the oil vapors, and the slow heating preventing fusion of the flux forming constituents. After the bitumen has been driven off, air is passed into the retort and heating continued to about 1050/sup 0/C, the result being a porous product suitable for insulating purposes or as a substitute for kieselguhr. The ground shale may be mixed prior to distillation with peat, sawdust, or the like, and with substances which yield acids, such as chlorides, more particularly magnesium chloride, the acids acting on the bitumen.

  15. Distilling coal

    Energy Technology Data Exchange (ETDEWEB)

    Blythe, F C

    1914-09-14

    In the destructive distillation of bituminous coal, heavy hydrocarbon oil, such as petroleum, kerosine, shale oil, and heavy tar oil, obtained in some cases during the process, is added to the coal, which is then distilled under pressure and at a comparatively low temperature regulated so as to produce a large proportion of hydrocarbon oils and a small proportion of permanent gas. In one method, about 5 to 10 parts of hydrocarbon oil are mixed with 100 parts of crushed or ground coal, and the mixture is heated in a closed vessel, provided in some cases with an agitator, under a pressure of about 60 lb/in/sup 2/, and the temperature may be gradually raised to 350/sup 0/C and then to about 500/sup 0/C. The heating may be by means of superheated steam with or without external heat.

  16. Process for distilling shales, peats, etc

    Energy Technology Data Exchange (ETDEWEB)

    Felizat, G

    1922-01-09

    The invention has for its object: a process for the distillation of shales, peats, and analogous products characterized by injecting across the substance a very rapid stream of superheated steam under pressure in order to effect a rapid removal of the products of distillation, to lower also the temperature at which it distills, to equalize the temperature throughout the mass, to hydrogenate the heavy hydrocarbons. An apparatus is put into operation characterized by the combination of a retort receiving the material to be distilled with a superheater for the steam, the combustion products which escape from the hearth of the superheater going to encircle the retort while the steam which comes off the superheater traverses this retort, the pressure of the steam being regulated by a convenient regulator; the products of the distillation result from the simultaneous action of the hot gases and steam on the contents of the retort being, on the other hand, separated at the outlet of this retort by means of cooling in a gas separator, a condenser, and part of the gas after being separated serving to heat the mentioned superheater.

  17. A direct contact between astrocyte and vitreous body is possible in the rabbit eye due to discontinuities in the basement membrane of the retinal inner limiting membrane

    Directory of Open Access Journals (Sweden)

    A. Haddad

    2003-02-01

    Full Text Available Different from most mammalian species, the optic nerve of the rabbit eye is initially formed inside the retina where myelination of the axons of the ganglion cells starts and vascularization occurs. Astrocytes are confined to these regions. The aforementioned nerve fibers known as medullated nerve fibers form two bundles that may be identified with the naked eye. The blood vessels run on the inner surface of these nerve fiber bundles (epivascularization and, accordingly, the accompanying astrocytes lie mostly facing the vitreous body from which they are separated only by the inner limiting membrane of the retina. The arrangement of the astrocytes around blood vessels leads to the formation of structures known as glial tufts. Fragments (N = 3 or whole pieces (N = 3 of the medullated nerve fiber region of three-month-old male rabbits (Orictolagus cuniculus were fixed in glutaraldehyde followed by osmium tetroxide, and their thin sections were examined with a transmission electron microscope. Randomly located discontinuities (up to a few micrometers long of the basement membrane of the inner limiting membrane of the retina were observed in the glial tufts. As a consequence, a direct contact between the astrocyte plasma membrane and vitreous elements was demonstrated, making possible functional interactions such as macromolecular exchanges between this glial cell type and the components of the vitreous body.

  18. Membranes for corrosive oxidations. Final CRADA report.

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, S. W.; Energy Systems

    2010-02-01

    drawbacks, particularly in the extraction phase. One general disadvantage of this technology is that hydrogen peroxide must be produced at large centralized plants where it is concentrated to 70% by distillation and transported to the users plant sites where it is diluted before use. Advanced membranes have the potential to enable more efficient, economic, and safe manufacture of hydrogen peroxide. Advanced membrane technology would allow filtration-based separation to replace the difficult liquid-liquid extraction based separation step of the hydrogen peroxide process. This would make it possible for hydrogen peroxide to be produced on-site in mini-plants at 30% concentration and used at the same plant location without distillation and transportation. As a result, production could become more cost-effective, safe and energy efficient.

  19. Mind the Organelle Gap - Peroxisome Contact Sites in Disease.

    Science.gov (United States)

    Castro, Inês Gomes; Schuldiner, Maya; Zalckvar, Einat

    2018-03-01

    The eukaryotic cell is organized as a complex grid system where membrane-bound cellular compartments, organelles, must be localized to the right place at the right time. One way to facilitate correct organelle localization and organelle cooperation is through membrane contact sites, areas of close proximity between two organelles that are bridged by protein/lipid complexes. It is now clear that all organelles physically contact each other. The main focus of this review is contact sites of peroxisomes, central metabolic hubs whose defects lead to a variety of diseases. New peroxisome contacts, their tethering complexes and functions have been recently discovered. However, if and how peroxisome contacts contribute to the development of peroxisome-related diseases is still a mystery. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Cascade Distiller System Performance Testing Interim Results

    Science.gov (United States)

    Callahan, Michael R.; Pensinger, Stuart; Sargusingh, Miriam J.

    2014-01-01

    The Cascade Distillation System (CDS) is a rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. Based upon the results of the 2009 distillation comparison test (DCT) and recommendations of the expert panel, the Advanced Exploration Systems (AES) Water Recovery Project (WRP) project advanced the technology by increasing reliability of the system through redesign of bearing assemblies and improved rotor dynamics. In addition, the project improved the CDS power efficiency by optimizing the thermoelectric heat pump (TeHP) and heat exchanger design. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell d International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades as compared to previous system performance. The system was challenged with Solution 1 from the NASA Exploration Life Support (ELS) distillation comparison testing performed in 2009. Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. A secondary objective of this testing is to evaluate the performance of the CDS as compared to the state of the art Distillation Assembly (DA) used in the ISS Urine Processor Assembly (UPA). This was done by challenging the system with ISS analog waste streams. This paper details the results of the AES WRP CDS performance testing.

  1. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Armour, J; Armour, H

    1889-05-07

    The invention relates to retorts and accessory apparatus for distilling shale or other oil-yielding minerals. A series of long vertical retorts, composed of fire-brick or similar refractory material, are arranged in two rows in a bench, being divided into groups of four by transverse vertical partitions. The retorts are surmounted by metal casings or hoppers into which the fresh mineral is charged, and from which the distillate passes off through lateral pipes. Any uncondensed gases from the retorts may be passed into the flues surrounding them by the pipe and burned. The products of combustion from a furnace pass through a series of horizontal flues, being compelled to pass completely round each retort before entering the flue above. The products from two or more sets pass from the upper flues into flues running along the top of the bench, and return through a central flue to the chimney.

  2. Distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, J M

    1884-06-03

    The invention relates to retorts for the destructive distillation of shale, dross, and other carbonaceous or oleaginous materials, and for the distillation and carbonization of sawdust, shavings, tan bark, and the like. The material is fed from a trapped hopper on a series of trays or casings of cast iron or other material, separated by flue spaces and arranged in a tier round a vertical rotating shaft passing through tubular pieces cast on the casings. The shaft is fitted with arms which carry stirring-blades so disposed that the material is shifted from side to side and slowly fed towards the ducts through which it passes to the casing next below, and is finally withdrawn from the apparatus by a pipe, which may be trapped or otherwise. Furnace gases are admitted through openings in the enclosing brickwork having settings to support the casings, the lowermost of which may be fitted below the inlet for furnace gases and their contents cooled by the circulation of cold water round them. The gaseous or volatile products of distillation pass to a condenser by means of openings and the pipe, which may be formed in sections to obtain access to the casings, or doors may be provided for this purpose. The ducts may be arranged alternately at the edge and center of the casings, which may be jacketed, and heated air or steam may be employed instead of furnace gases. Means may also be provided for admitting superheated steam into one or more of the casings.

  3. Mise au point d'un nouvel appareil de "distillation isotherme" Disterm Development of Distherm, a New Isothermal Distillation Apparatus

    Directory of Open Access Journals (Sweden)

    Mouton M.

    2006-11-01

    Full Text Available Les études analytiques de distillats pétroliers d'intervalles d'ébullition élevés doivent être réalisées sur des produits préparés dans des conditions de distillation extrêmement douces, de manière à conserver intactes toutes les espèces chimiques initialement contenues dans le pétrole brut en l'état. Pour répondre à cet objectif, le Comité de Distillation du GEC (Groupe d'Études Concertées sur l'analyse des fractions lourdes du pétrole, réunissant Compagnie Francaise de Raffinage (CFR, Société Nationale Elf Aquitaine (SNEA et Institut Français du Pétrole (IFP a mis au point un schéma de préparation spécial de ces distillats, faisant appel à des techniques de distillation continue, de type « isotherme» et « moléculaire ». Dans ce cadre, le Comité de Distillation du GEC a été amené à développer un nouvel appareillage de distillation x isotherme », permettant de réduire, sans craquage, tout pétrole brut jusqu'à une température maximale comprise entre 350 et 380 °C. On décrit dans cet article ce nouvel ensemble de distillation, ainsi que ses conditions opératoires de fonctionnement. On y donne aussi un aperçu de la précision de la méthode de distillation réalisable avec cet appareil, ainsi que de la qualité de fractionnement obtenu.Enfin, à l'aide de quelques exemples particuliers, on montre que le domaine d'application de l'appareil peut être étendu à des produits autres que des pétroles bruts. Analytical examinations of high-boiling-range petroleum distillates must be made with products prepared under extremely mild distillation conditions so as ta maintain intact all the chemical species initially present in the original crude oil.

  4. In-line quantification and characterization of membrane fouling

    KAUST Repository

    Bucs, Szilard

    2016-06-16

    Methods of detecting, quantifying and/or characterizing the fouling of a device from a combination of pressure and spectroscopic data are provided. The device can be any device containing components susceptible to fouling. Components can include membranes, pipes, or reactors. Suitable devices include membrane devices, heat exchangers, and chemical or bio-reactors. Membrane devices can include, for example, microfiltration devices, ultrafiltration devices, nanofiltration devices, reverse osmosis, forward osmosis, osmosis, reverse electrodialysis, electro- deionisation or membrane distillation devices. The methods can be applied to any type of membrane, including tubular, spiral, hollow fiber, flat sheet, and capillary membranes. The spectroscopic characterization can include measuring one or more of the absorption, fluorescence, or raman spectroscopic data of one or more foulants. The methods can allow for the early detection and/or characterization of fouling. The characterization can include determining the specific foulant(s) or type of foulant(s) present. The characterization of fouling can allow for the selection of an appropriate de-fouling method and timing.

  5. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of turpentine...

  6. Solar distillation between a simple and double-glazing

    Directory of Open Access Journals (Sweden)

    Abderrahmane KHECHEKHOUCHE

    2017-12-01

    Full Text Available The south-east region of Algeria suffers from a great socio-economic problem that affects a large population. Faced with the unavailability of drinking water, solar distillation; which appears to be a suitable and inexpensive solution; was adopted by local researchers. Improving the productivity of a solar greenhouse distiller is the subject of several researches in the world. As it is well known, distiller with simple glazing is wildly studied but unfortunately has feeble efficiency. Double glazing is a method that increases the efficiency of a flat solar collector. The idea is to use the same technique on a single-slope solar distiller (50 x 50 cm. Two glass plates separated by 1 cm between them air is trapped. Experience shows that this technique has a negative effect on the productivity of the distiller with a rate of 88.63%; it means 9 times. So double glazing is not recommended in the single slope solar distiller.

  7. Distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Irvine, R

    1884-04-04

    In obtaining paraffin by distillation of shales, etc., containing sulfur, the steam used for heating is charged with ammonia or ammonium carbonate in suspension. This prevents the sulfur from decomposing the paraffin. The ammonia, etc., may also be used alone or in solution in water.

  8. Effect of operating parameters and membrane characteristics on air gap membrane distillation performance for the treatment of highly saline water

    KAUST Repository

    Xu, Jingli; Singh, Yogesh Balwant; Amy, Gary L.; Ghaffour, NorEddine

    2016-01-01

    , such as feed temperatures, feed flow velocities and salt concentrations reaching 120 g/L, and different membrane characteristics, such as membrane material, thickness, pore size and support layer, using a locally designed and fabricatd AGMD module and spacer

  9. [Study on essential oil separation from Forsythia suspensa oil-bearing water body based on vapor permeation membrane separation technology].

    Science.gov (United States)

    Zhang, Qian; Zhu, Hua-Xu; Tang, Zhi-Shu; Pan, Yong-Lan; Li, Bo; Fu, Ting-Ming; Yao, Wei-Wei; Liu, Hong-Bo; Pan, Lin-Mei

    2018-04-01

    To investigate the feasibility of vapor permeation membrane technology in separating essential oil from oil-water extract by taking the Forsythia suspensa as an example. The polydimethylsiloxane/polyvinylidene fluoride (PDMS/PVDF) composite flat membrane and a polyvinylidene fluoride (PVDF) flat membrane was collected as the membrane material respectively. Two kinds of membrane osmotic liquids were collected by self-made vapor permeation device. The yield of essential oil separated and enriched from two kinds of membrane materials was calculated, and the microscopic changes of membrane materials were analyzed and compared. Meanwhile, gas chromatography-mass spectrometry (GC-MS) was used to compare and analyze the differences in chemical compositions of essential oil between traditional steam distillation, PVDF membrane enriched method and PDMS/PVDF membrane enriched method. The results showed that the yield of essential oil enriched by PVDF membrane was significantly higher than that of PDMS/PVDF membrane, and the GC-MS spectrum showed that the content of main compositions was higher than that of PDMS/PVDF membrane; The GC-MS spectra showed that the components of essential oil enriched by PVDF membrane were basically the same as those obtained by traditional steam distillation. The above results showed that vapor permeation membrane separation technology shall be feasible for the separation of Forsythia essential oil-bearing water body, and PVDF membrane was more suitable for separation and enrichment of Forsythia essential oil than PDMS/PVDF membrane. Copyright© by the Chinese Pharmaceutical Association.

  10. Distillation process using microchannel technology

    Science.gov (United States)

    Tonkovich, Anna Lee [Dublin, OH; Simmons, Wayne W [Dublin, OH; Silva, Laura J [Dublin, OH; Qiu, Dongming [Carbondale, IL; Perry, Steven T [Galloway, OH; Yuschak, Thomas [Dublin, OH; Hickey, Thomas P [Dublin, OH; Arora, Ravi [Dublin, OH; Smith, Amanda [Galloway, OH; Litt, Robert Dwayne [Westerville, OH; Neagle, Paul [Westerville, OH

    2009-11-03

    The disclosed invention relates to a distillation process for separating two or more components having different volatilities from a liquid mixture containing the components. The process employs microchannel technology for effecting the distillation and is particularly suitable for conducting difficult separations, such as the separation of ethane from ethylene, wherein the individual components are characterized by having volatilities that are very close to one another.

  11. Performance indicators of bioethanol distillation

    International Nuclear Information System (INIS)

    Marriaga, Nilson

    2009-01-01

    The increase of biofuels demand accelerates the construction of new production plants and technological improvements in the process so the development of versatile tools for evaluating alternatives becomes an undeniable challenge. It was established through heuristic rules, thermodynamic analysis and simulation computer the energy consumption and performance indicators that govern, from fermented mash (ethanol 8.5 % v/v), the distillation of various capacities for bioethanol production: 20, 60, 100 and 150 KLD (kiloliters / day) through Aspen PlusTM simulator. It was found that the distillation demand nearly 30% of heat that would be obtained by burning alcohol fuel produced thus it is necessary the use of raw materials that generate enough biomass to produce the steam required. In addition, correlations were found to allow for easy diameters of distillation columns in terms of production capacity.

  12. Apparatus for distillation of bituminous material

    Energy Technology Data Exchange (ETDEWEB)

    Carthaus, E; von Rittersberg, K; Abraham, A

    1917-05-03

    Apparatus for dry distillation of bituminous material, such as oil shale and brown coal with simultaneous fractional separation of the distillate, consists in the fact, that the domed water-cooled condenser, arranged above the conveyer carrying it, is divided by double vertical partitions in the chamber.

  13. 7 CFR 58.331 - Starter distillate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Starter distillate. 58.331 Section 58.331 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.331 Starter distillate. The refined flavor components when used to flavor butter and related...

  14. Binary release of ascorbic acid and lecithin from core-shell nanofibers on blood-contacting surface for reducing long-term hemolysis of erythrocyte.

    Science.gov (United States)

    Shi, Qiang; Fan, Qunfu; Ye, Wei; Hou, Jianwen; Wong, Shing-Chung; Xu, Xiaodong; Yin, Jinghua

    2015-01-01

    There is an urgent need to develop blood-contacting biomaterials with long-term anti-hemolytic capability. To obtain such biomaterials, we coaxially electrospin [ascorbic acid (AA) and lecithin]/poly (ethylene oxide) (PEO) core-shell nanofibers onto the surface of styrene-b-(ethylene-co-butylene)-b-styrene elastomer (SEBS) that has been grafted with poly (ethylene glycol) (PEG) chains. Our strategy is based on that the grafted layers of PEG render the surface hydrophilic to reduce the mechanical injure to red blood cells (RBCs) while the AA and lecithin released from nanofibers on blood-contacting surface can actively interact with RBCs to decrease the oxidative damage to RBCs. We demonstrate that (AA and lecithin)/PEO core-shell structured nanofibers have been fabricated on the PEG grafted surface. The binary release of AA and lecithin in the distilled water is in a controlled manner and lasts for almost 5 days; during RBCs preservation, AA acts as an antioxidant and lecithin as a lipid supplier to the membrane of erythrocytes, resulting in low mechanical fragility and hemolysis of RBCs, as well as high deformability of stored RBCs. Our work thus makes a new approach to fabricate blood-contacting biomaterials with the capability of long-term anti-hemolysis. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Contact isotopic- and contact ion-exchange between two adsorbents

    International Nuclear Information System (INIS)

    Bunzl, K.; Mohan, R.; Haimerl, M.

    1975-01-01

    The kinetics of contact ion exchange processes between an ion exchange membrane and resin ion exchange beads, stirred in pure water, was investigated. A general criterion was derived, which indicates whether diffusion of the ions between the intermingling electric double layers or the collision frequency between the two adsorbents is the rate dermining step. Since the latter process proved to be rate controlling under our experimental conditions, the corresponding rate equations were derived under various initial and boundary conditions. Experimentally, the kinetics of contact isotopic exchange of Cs + - and Na + -ions as well as of the reverse contact ion exchange process of Cs + -versus Na + -ions were investigated by using Na 22 and Cs 137 radioisotopes. The experiments reveal in quantitative accord with the theory that the rate of collision controlled contact ion exchange processes depends mainly on the 'exchange coefficient', the separation factor and the collision frequency. While the latter two quantities were determined independently by separate experiments, the 'exchange coefficient' was evaluated from a contact isotopic exchange experiment. (orig.) [de

  16. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Allison, C A

    1906-05-22

    The invention relates to an apparatus in which the destructive distillation or coking of coal, peat, shale, etc., is carried out by means of a current of hot gases at a temperature of 700--800/sup 0/F., as described in Specification No. 11,925, A.D. 1906.

  17. Membrane-based ethylene/ethane separation: The upper bound and beyond

    KAUST Repository

    Rungta, Meha

    2013-08-02

    Ethylene/ethane separation via cryogenic distillation is extremely energy-intensive, and membrane separation may provide an attractive alternative. In this paper, ethylene/ethane separation performance using polymeric membranes is summarized, and an experimental ethylene/ethane polymeric upper bound based on literature data is presented. A theoretical prediction of the ethylene/ethane upper bound is also presented, and shows good agreement with the experimental upper bound. Further, two ways to overcome the ethylene/ethane upper bound, based on increasing the sorption or diffusion selectivity, is also discussed, and a review on advanced membrane types such as facilitated transport membranes, zeolite and metal organic framework based membranes, and carbon molecular sieve membranes is presented. Of these, carbon membranes have shown the potential to surpass the polymeric ethylene/ethane upper bound performance. Furthermore, a convenient, potentially scalable method for tailoring the performance of carbon membranes for ethylene/ethane separation based on tuning the pyrolysis conditions has also been demonstrated. © 2013 American Institute of Chemical Engineers.

  18. Wine distillates: practical operating recipe formulation for stills.

    Science.gov (United States)

    Osorio, Daniel; Pérez-Correa, J Ricardo; Biegler, Lorenz T; Agosin, Eduardo

    2005-08-10

    Consumer perceptions of flavors are associated with the chemical composition of foods. However, consumer preferences change; therefore, it is necessary for food manufacturers to be able to adapt their products. Unlike in aged spirits, the chemical composition of young spirits is determined during distillation; therefore, this is where distillers must tailor their operating recipes to the new trends. Even for an experienced distiller, the complexity of the process makes adapting the operating recipe far from straightforward. In this study, we developed a methodology for generating practical recipes that makes use of computer simulations and optimization techniques. We used Pisco Brandy, a young Muscat wine distillate from Chile and Peru as our case study. Even so, because our methodology is independent of the chemical composition of the broth, it can be applied throughout the industry. Drawing on the experience and preferences of industry enologists, we designed a preferred distillate and used our methodology to obtain the appropriate recipe. This recipe was validated in lab scale experiments, and we obtained a much closer distillate to the desired prescription than commercial products.

  19. Novel Ultrafine Fibrous Poly(tetrafluoroethylene Hollow Fiber Membrane Fabricated by Electrospinning

    Directory of Open Access Journals (Sweden)

    Qinglin Huang

    2018-04-01

    Full Text Available Novel poly(tetrafluoroethylene (PTFE hollow fiber membranes were successfully fabricated by electrospinning, with ultrafine fibrous PTFE membranes as separation layers, while a porous glassfiber braided tube served as the supporting matrix. During this process, PTFE/poly(vinylalcohol (PVA ultrafine fibrous membranes were electrospun while covering the porous glassfiber braided tube; then, the nascent PTFE/PVA hollow fiber membrane was obtained. In the following sintering process, the spinning carrier PVA decomposed; meanwhile, the ultrafine fibrous PTFE membrane shrank inward so as to further integrate with the supporting matrix. Therefore, the ultrafine fibrous PTFE membranes had excellent interface bonding strength with the supporting matrix. Moreover, the obtained ultrafine fibrous PTFE hollow fiber membrane exhibited superior performances in terms of strong hydrophobicity (CA > 140°, high porosity (>70%, and sharp pore size distribution. The comprehensive properties indicated that the ultrafine fibrous PTFE hollow fiber membranes could have potentially useful applications in membrane contactors (MC, especially membrane distillation (MD in harsh water environments.

  20. Vacuum distillation of plutonium pyrochemical salts

    International Nuclear Information System (INIS)

    Bourges, Gilles; Faure, S.; Fiers, B.; Saintignon, S.; Lemoine, O.; Cardona-Barrau, D.; Devillard, D.

    2012-01-01

    A pyrochemical process is developed to upgrade the safety of plutonium spent salts interim storage. The feed material, consisting of alkali or alkali-earth chlorides containing various Pu and Am species, is first oxidized to convert the actinides into oxides. Then the chlorides are removed by vacuum distillation which requires temperature from 750 degrees C to 1100 degrees C. After a comprehensive R and D program, full-scale equipment was built to test the distillation of active salts. Tests with NaCl/KCl oxidized spent salt give decontamination factor of chlorides higher than 20000. The distilled salt meets the radiologic requirements to be discarded as low level waste. (authors)

  1. Method and arrangement of distillation of shales

    Energy Technology Data Exchange (ETDEWEB)

    Bergh, S V

    1920-03-29

    A method is given of distilling shale and other bituminous materials utilizing the heat from the combustion of the residue, possibly with additional heat from other fuels. It is characterized by the shale, which is arranged in layers, being first submitted to a process of distillation utilizing the heat mentioned, and at the same time recovering the products of distillation, and second the shale being burned without disturbing the layers to any appreciable extent. The patent has 16 more claims.

  2. Evolution of Volatile Compounds during the Distillation of Cognac Spirit.

    Science.gov (United States)

    Awad, Pierre; Athès, Violaine; Decloux, Martine Esteban; Ferrari, Gérald; Snakkers, Guillaume; Raguenaud, Patrick; Giampaoli, Pierre

    2017-09-06

    Cognac wine spirit has a complex composition in volatile compounds which contributes to its organoleptic profile. This work focused on the batch distillation process and, in particular, on volatile compounds specifically produced by chemical reactions during the distillation of Cognac wine spirit, traditionally conducted in two steps with charentais pot stills. The aim of this study was to characterize these volatile compounds formed during distillation. Sampling has been performed on the distillates and inside the boiler during a typical Cognac distillation. The analysis of these samples allowed us to perform a mass balance and to point out several types of volatile compounds whose quantities strongly increased during the distillation process. These compounds were distinguished by their chemical family. It has been found that the first distillation step was decisive for the formation of volatile compounds. Moreover, 2 esters, 3 aldehydes, 12 norisoprenoids, and 3 terpenes were shown to be generated during the process. These results suggest that some volatile compounds found in Cognac spirit are formed during distillation due to chemical reactions induced by high temperature. These findings give important indications to professional distillers in order to enhance the product's quality.

  3. Activation of PVDF membranes through facile hydroxylation of the polymeric dope

    KAUST Repository

    Al-Gharabli, Samer; Mavukkandy, Musthafa O.; Kujawa, Joanna; Nunes, Suzana Pereira; Arafat, Hassan A.

    2017-01-01

    A method comprising a two-step alkali/acid treatment of poly (vinylidene fluoride) (PVDF) polymer is developed for the fabrication of flat-sheet PVDF membranes functionalized with labile hydroxyl groups. This method involves the application of a short-duration modification in alkali medium (5% KOH). Extensive characterizations were performed on the prepared membranes. Modification of the polymer altered the crystallinity of the PVDF from a mixture of both α and β phases to a predominant β phase. Lower work of adhesion of the modified membrane indicated the formation of a more hydrophobic and wetting-resistant membrane surface. Centrifugation of the polymer dope after the modification had a pronounced impact on the properties of the resultant membranes. This protocol could be utilized in fine-tuning the properties of PVDF membranes for various target-specific applications such as membrane distillation. This method can also be used in functionalizing PVDF membranes further by exploiting the labile –OH group present on the membrane surface.

  4. Activation of PVDF membranes through facile hydroxylation of the polymeric dope

    KAUST Repository

    Al-Gharabli, Samer

    2017-10-30

    A method comprising a two-step alkali/acid treatment of poly (vinylidene fluoride) (PVDF) polymer is developed for the fabrication of flat-sheet PVDF membranes functionalized with labile hydroxyl groups. This method involves the application of a short-duration modification in alkali medium (5% KOH). Extensive characterizations were performed on the prepared membranes. Modification of the polymer altered the crystallinity of the PVDF from a mixture of both α and β phases to a predominant β phase. Lower work of adhesion of the modified membrane indicated the formation of a more hydrophobic and wetting-resistant membrane surface. Centrifugation of the polymer dope after the modification had a pronounced impact on the properties of the resultant membranes. This protocol could be utilized in fine-tuning the properties of PVDF membranes for various target-specific applications such as membrane distillation. This method can also be used in functionalizing PVDF membranes further by exploiting the labile –OH group present on the membrane surface.

  5. Folded membrane dialyzer with mechanically sealed edges

    Energy Technology Data Exchange (ETDEWEB)

    Markley, F.W.

    A semipermeable membrane is folded in accordion fashion to form a stack of pleats and the edges are sealed so as to isolate the opposite surfaces of the membrane. The stack is contained within a case that provides ports for flow of blood in contact with one surface of the membrane through channels formed by the pleats and also provides ports for flow of a dialysate through channels formed by the pleats in contact with the other surface of the membrane. The serpentine side edges of the membrane are sealed by a solidified plastic material, whereas effective mechanical means are provided to seal the end edges of the folded membrane. The mechanical means include a clamping strip which biases case sealing flanges into a sealed relationship with end portions of the membrane near the end edges, which portions extend from the stack and between the sealing flanges.

  6. Energy savings in distillation via identification of useful configurations

    Science.gov (United States)

    Shah, Vishesh Hemanshu

    Recent market and environmental forces require the rapid development of better and cheaper separation process solutions. Especially for multicomponent mixtures, there are several feasible separation process solutions differing significantly in cost and energy consumption in spite of carrying out the same overall process. Therefore a systematic method to identify and design optimal multicomponent separation sequences is needed instead of relying on the inventive activity of a few experienced engineers. Even for a commonly perceived "mature" technology such as distillation, until recently there has been an absence of systematic methods to (i) elucidate all possible separation configurations and to (ii) identify energy efficient candidates. This research aims to address these needs. In this work, we focus on the continuous distillation of non-azeotropic mixtures into n distinct composition final product streams. We develop a computationally efficient and easy-to-use mathematical framework to generate all the basic distillation configurations that use exactly (n-1) distillation columns to carry out this n-component separation. We extend the framework to generate all the additional distillation configurations with thermal coupling. We observe that the search space of distillation configurations grows very rapidly as the number of product streams increases. For instance, for a mixture to be separated into 4 product streams, we can choose from 18 basic configurations and 134 additional configurations with thermal coupling; while for a mixture to be separated into 8 product streams, we can choose from 15,767,207 basic configurations and 29,006,926,681 additional configurations with thermal coupling. The next challenge for a process engineer is to be able to quickly prune the search space to a handful of attractive energy efficient candidates that can be studied in greater detail. To this effect, we develop a quick screening optimization tool that identifies configurations

  7. Process of distillation of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Saxton, A L

    1968-08-16

    In an oil-shale distillation apparatus with a single retort, in which separate zones of preheating, distillation, combustion, and cooling are maintained, the operation is conducted at a presssure higher than the atmospheric pressure, preferably at a gage pressure between about 0.35 and 7.0 bars. This permits increasing the capacity of the installation.

  8. Final Report - Energy Reduction and Advanced Water Removal via Membrane Solvent Extraction Technology

    Energy Technology Data Exchange (ETDEWEB)

    Reed, John; Fanselow, Dan; Abbas, Charles; Sammons, Rhea; Kinchin, Christopher

    2014-08-06

    3M and Archer Daniels Midland (ADM) collaborated with the U.S. Department of Energy (DOE) to develop and demonstrate a novel membrane solvent extraction (MSE) process that can substantially reduce energy and water consumption in ethanol production, and accelerate the fermentation process. A cross-flow membrane module was developed, using porous membrane manufactured by 3M. A pilot process was developed that integrates fermentation, MSE and vacuum distillation. Extended experiments of 48-72 hours each were conducted to develop the process, verify its performance and begin establishing commercial viability.

  9. Retorts for distilling carbonaceous material

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, H E

    1921-09-12

    A retort for distilling carbonaceous material is described in which a mass of such material is retained in a pocket formed between an outer wall and an internal wall which is perforated to permit the free escape of distilled products, the retorts having heating means that directly heat the retort but are so related to the pocket that the material therein is heated indirectly and simultaneously from all sides entirely by heat conducted thereto by the walls.

  10. Three methods to distill multipartite entanglement over bipartite noisy channels

    International Nuclear Information System (INIS)

    Lee, Soojoon; Park, Jungjoon

    2008-01-01

    We first assume that there are only bipartite noisy qubit channels in a given multipartite system, and present three methods to distill the general Greenberger-Horne-Zeilinger state. By investigating the methods, we show that multipartite entanglement distillation by bipartite entanglement distillation has higher yield than ones in the previous multipartite entanglement distillations

  11. Impact of Grape Varieties on Wine Distillates Flavour

    Directory of Open Access Journals (Sweden)

    Mara Banović

    2002-01-01

    Full Text Available Aroma is a phenomenon that occurrs when food and live organism mutually react during the process of consumption. Many factors influence the making of aroma of wine distillates (e.g. cognac during the technological process of distillation. It is extremely difficult to bring an objective judgement on the influence of individual factors since aroma is very subjective in its nature. The possibility of objective assessment of the influence of grape varieties on wine distillate was performed in this work using a computer in processing the results of cromatographic analyses of aroma substances. The given results were verified by sensor analyses. The achieved results have shown that mathematical model for calculating aroma chromatogram similarity can be successfully used for objective assessment of the influence of individual factors on aroma of wine distillates and that grape varieties have significant impact on aroma and the quality of wine distillates.

  12. Energy consumption maps for quaternary distillation sequences

    DEFF Research Database (Denmark)

    Gomez-Castro, F.I.; Ramírez-Vallejo, N.E.; Segovia-Hernandez, J.G.

    2016-01-01

    Thermally coupled distillation columns represent a very interesting option for the intensification of distillation systems in order to reduce the energy consumption, and, as a consequence, the environmental impact of the separation process. Several thermally coupled distillation schemes can......, for a given mixture, depends on the nature of the mixture, usually quantified for ternary mixtures through the ease of separation index (ESI), and also on the feed composition. As can be noticed, the size of the design and optimization problem increases when these variables are considered in the generation...

  13. Destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, H; Laing, B

    1927-12-23

    Oil bearing solids such as coal, tar sands, oil shales, or the like, are distilled in a current of hot gas and are first preheated to a temperature above that at which the heaviest oil fractions in the vapors are liable to condense, for example 100 to 250/sup 0/C, according to the volume of gas passing through the retort, temperature being in inverse proportion to the quantity of oxygen containing constituents in the charge. When the distillation takes place in a controlled volume of hot inert gas of 45,000 cubic feet per ton and the volume of oil recovered is about 20 gallons per ton, the material is preheated to 200 to 250/sup 0/C, when the volume of gas used is 100,000 cubic feet the preheating temperature is 150/sup 0/C. The temperatures of the retort dust extractor etc. do not fall below 100 to 150/sup 0/C until actual condensation of the oil vapor is desired. Specification 287,381 is referred to, and Specification 287,037 also is referred to in the Provisional Specification.

  14. Distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Byrom, W A; Bennett, J A.B.

    1884-02-22

    Effecting the separation of the various products of the distillation of coal, shale, etc., by taking advantage of the graduated temperature of successive portions of the length of mechanical retorts is described. The substances entering from the hopper are gradually heated in their progress and give off a series of products in their order of volatilization, which pass from openings in the retort through a series of ascension pipes into collecting-vessels. The vessels are designed to contain different portions of the distillate and are sealed against the escape of uncondensed vapor or gas by the condensed liquid. Each of the ascension pipes communicates above its vessel with a common pipe to convey away permanent gases. The flues for heating the retort may be so arranged as to give the greatest heat at the end farthest from the point of entrance, or the stages of heat may be self-regulated by the time necessary for the material to acquire heat as it travels. If necessary the pipes may be fitted with refrigerating-appliances.

  15. Cascade Distillation Subsystem Development: Progress Toward a Distillation Comparison Test

    Science.gov (United States)

    Callahan, M. R.; Lubman, A.; Pickering, Karen D.

    2009-01-01

    Recovery of potable water from wastewater is essential for the success of long-duration manned missions to the Moon and Mars. Honeywell International and a team from NASA Johnson Space Center (JSC) are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The wastewater processor, referred to as the Cascade Distillation Subsystem (CDS), utilizes an innovative and efficient multistage thermodynamic process to produce purified water. The rotary centrifugal design of the system also provides gas/liquid phase separation and liquid transport under microgravity conditions. A five-stage subsystem unit has been designed, built, delivered and integrated into the NASA JSC Advanced Water Recovery Systems Development Facility for performance testing. A major test objective of the project is to demonstrate the advancement of the CDS technology from the breadboard level to a subsystem level unit. An initial round of CDS performance testing was completed in fiscal year (FY) 2008. Based on FY08 testing, the system is now in development to support an Exploration Life Support (ELS) Project distillation comparison test expected to begin in early 2009. As part of the project objectives planned for FY09, the system will be reconfigured to support the ELS comparison test. The CDS will then be challenged with a series of human-gene-rated waste streams representative of those anticipated for a lunar outpost. This paper provides a description of the CDS technology, a status of the current project activities, and data on the system s performance to date.

  16. A comparative evaluation of nitrogen compounds in petroleum distillates

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Dheer; Chopra, Anju; Patel, Mitra Bhanu; Sarpal, Amarjit Singh [Indian Oil Corporation Limited, Faridabad (India). Research and Development Centre

    2011-07-15

    Although the concentration of nitrogen compounds in crude oil is relatively low, they can become more concentrated in petroleum distillates and poison the catalysts used in refining processes. They cause undesirable deposits, color formation and odor in products; they also contribute to air pollution and some are highly carcinogenic. The poisoned catalyst becomes deactivated for hydrodesulfurization and unable to remove sulfur from middle distillates. In order to understand the effect on catalytic processes, it is desirable to identify the nitrogen compounds in various petroleum distillates. This paper compares the nitrogen species profiles in different petroleum distillates using a nitrogen chemiluminescence detector. In addition, four different petroleum distillate samples from different refineries were analyzed to find the variation in their nitrogen profiles. The nitrogen compounds in petroleum distillate samples were identified as anilines, quinolines, indoles, and carbazoles and their alkyl derivatives. Quantitation was carried out against known reference standards. The quantitative data were compared to the total nitrogen content determined by elemental analysis. (orig.)

  17. Clinical observation on bandage type corneal contact lens applied after pterygium excision combined with fresh amniotic membrane transplantation

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2018-04-01

    Full Text Available AIM: To evaluate the clinical effect of fresh amniotic membrane transplantation in combination with bandage type corneal contact lens in the treatment of pterygium. METHODS: This study was a prospective analysis of 600 pterygium excision patients(600 cases, 600 eyesin the He Eye Hospital from January 2016 to June 2016. The patients were randomly and evenly divided into two groups: observation group and control group, 300 cases in each group(300 eyes. Observation group wore the bandage type corneal contact lens after surgery and took it down at fifth day. The control group did not. The degree of pain after surgery were evaluated at 2h, 1, 3 and 5d after surgery. The clinical outcomes in these two groups were compared in a 12mo postoperative follow-up observation. RESULTS: There were no significant differences between the observation and control group in the percentage of age and gender and size of the pterygium(P>0.05. After surgery, the degree of pain of treatment group significantly decreased compared to control group, the difference was statistically significant(PP>0.05. CONCLUSION: Bandage contact lenses could significantly release pain response after pterygium excision. But it can not reduce the recurrence rate.

  18. Asymptotic speedups, bisimulation and distillation (Work in progress)

    DEFF Research Database (Denmark)

    Jones, Neil; Hamilton, G. W.

    2015-01-01

    Distillation is a fully automatic program transformation that can yield superlinear program speedups. Bisimulation is a key to the proof that distillation is correct, i.e., preserves semantics. However the proof, based on observational equivalence, is insensitive to program running times....... This paper shows how distillation can give superlinear speedups on some “old chestnut” programs well-known from the early program transformation literature: naive reverse, factorial sum, and Fibonacci....

  19. Effective As(III) Removal by A Multi-Charged Hydroacid Complex Draw Solute Facilitated Forward Osmosis-Membrane Distillation (FO-MD) Processes.

    Science.gov (United States)

    Ge, Qingchun; Han, Gang; Chung, Tai-Shung

    2016-03-01

    Effective removal of As(III) from water by an oxalic acid complex with the formula of Na3[Cr(C2O4)3] (Na-Cr-OA) is demonstrated via an forward osmosis-membrane distillation (FO-MD) hybrid system in this study. Na-Cr-OA first proved its superiority as a draw solute with high water fluxes and negligible reverse fluxes in FO, then a systematic investigation of the Na-Cr-OA promoted FO process was conducted to ascertain the factors in As(III) removal. Relatively high water fluxes of 28 LMH under the FO mode and 74 LMH under the pressure retarded osmosis (PRO) mode were achieved when using a 1000 ppm As(III) solution as the feed and 1.0 M Na-Cr-OA as the draw solution at 60 °C. As(III) removal with a water recovery up to 21.6% (FO mode) and 48.3% (PRO mode) were also achieved in 2 h. An outstanding As(III) rejection with 30-3000 μg/L As(III) in the permeate was accomplished when As(III) feed solutions varied from 5 × 10(4) to 1 × 10(6) μg/L, superior to the best FO performance reported for As(III) removal. Incorporating MD into FO not only makes As(III) removal sustainable by reconcentrating the Na-Cr-OA solution simultaneously, but also reduces the As(III) concentration below 10 μg/L in the product water, meeting the WHO standard.

  20. Refreshment topics II: Design of distillation columns

    Directory of Open Access Journals (Sweden)

    Milojević Svetomir

    2006-01-01

    Full Text Available For distillation column design it is necessary to define all the variable parameters such as component concentrations in different streams temperatures, pressures, mass and energy flow, which are used to represent the separation process of some specific system. They are related to each other according to specific laws, and if the number of such parameters exceeds the number of their relationships, in order to solve a problem some of them must be specified in advance or some constraints assumed for the mass balance, the balance of energy, phase equilibria or chemical equilibria. Knowledge of specific elements which are the constituents of a distillation unit must be known to define the number of design parameters as well as some additional apparati also necessary to realize the distilation. Each separate apparatus might be designed and constructed only if all the necessary and variable parameters for such a unit are defined. This is the right route to solve a distilation unit in many different cases. The construction of some distillation unit requires very good knowledge of mass, heat and momentum transfer phenomena. Moreover, the designer needs to know which kind of apparatus will be used in the distillation unit to realize a specific production process. The most complicated apparatus in a rectification unit is the distillation column. Depending on the complexity of the separation process one, two or more columns are often used. Additional equipment are heat exchangers (reboilers, condensers, cooling systems, heaters, separators, tanks for reflux distribution, tanks and pumps for feed transportation, etc. Such equipment is connected by pipes and valves, and for the normal operation of a distillation unit other instruments for measuring the flow rate, temperature and pressure are also required. Problems which might arise during the determination and selection of such apparati and their number requires knowledge of the specific systems which must

  1. 27 CFR 26.40 - Marking containers of distilled spirits.

    Science.gov (United States)

    2010-04-01

    ... spirits. The distiller, rectifier, or bottler shall serially number each case, barrel, cask, or similar... the container, the distiller, rectifier, or bottler shall plainly print, stamp, or stencil with... barrel, cask or similar container or on one side of each case, as follows: (a) The name of the distiller...

  2. Cascade Distillation Subsystem Development: Early Results from the Exploration Life Support Distillation Technology Comparison Test

    Science.gov (United States)

    Callahan, Michael R.; Patel, Vipul; Pickering, Karen D.

    2010-01-01

    In 2009, the Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, California) was assessed in the National Aeronautics and Space Administration (NASA) Exploration Life Support (ELS) distillation comparison test. The purpose of the test was to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. The CDS portion of the comparison test was conducted between May 6 and August 19, 2009. The system was challenged with two pretreated test solutions, each intended to represent a feasible wastewater generated in a surface habitat. The 30-day equivalent wastewater loading volume for a crew of four was intended to be processed for each wastewater solution. Test Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. Test Solution 2 contained the addition of human-generated hygiene wastewater to the solution 1 waste stream components. Approximately 1500 kg of total wastewater was processed through the CDS during testing. Respective recoveries per solution were 93.4 +/- 0.7 and 90.3 +/- 0.5 percent. The average specific energy of the system during testing was calculated to be less than 120 W-hr/kg. The following paper provides detailed information and data on the performance of the CDS as challenged per the ELS distillation comparison test.

  3. Distillation modeling for a uranium refining process

    International Nuclear Information System (INIS)

    Westphal, B.R.

    1996-01-01

    As part of the spent fuel treatment program at Argonne National Laboratory, a vacuum distillation process is being employed for the recovery of uranium following an electrorefining process. Distillation of a salt electrolyte, containing a eutectic mixture of lithium and potassium chlorides, from uranium is achieved by a simple batch operation and is termed open-quotes cathode processingclose quotes. The incremental distillation of electrolyte salt will be modeled by an equilibrium expression and on a molecular basis since the operation is conducted under moderate vacuum conditions. As processing continues, the two models will be compared and analyzed for correlation with actual operating results. Possible factors that may contribute to aberrations from the models include impurities at the vapor-liquid boundary, distillate reflux, anomalous pressure gradients, and mass transport phenomena at the evaporating surface. Ultimately, the purpose of either process model is to enable the parametric optimization of the process

  4. Distillation modeling for a uranium refining process

    Energy Technology Data Exchange (ETDEWEB)

    Westphal, B.R.

    1996-03-01

    As part of the spent fuel treatment program at Argonne National Laboratory, a vacuum distillation process is being employed for the recovery of uranium following an electrorefining process. Distillation of a salt electrolyte, containing a eutectic mixture of lithium and potassium chlorides, from uranium is achieved by a simple batch operation and is termed {open_quotes}cathode processing{close_quotes}. The incremental distillation of electrolyte salt will be modeled by an equilibrium expression and on a molecular basis since the operation is conducted under moderate vacuum conditions. As processing continues, the two models will be compared and analyzed for correlation with actual operating results. Possible factors that may contribute to aberrations from the models include impurities at the vapor-liquid boundary, distillate reflux, anomalous pressure gradients, and mass transport phenomena at the evaporating surface. Ultimately, the purpose of either process model is to enable the parametric optimization of the process.

  5. Design and construction of a Fresnel linear distiller

    International Nuclear Information System (INIS)

    Saettone, E.

    2014-01-01

    It was designed a Fresnel linear distiller based on optical calculations obtained from taking into account Lima's latitude value, Earth inclination angle and heat absorber cavity's dimensions. The 5.6 m 2 reflective surface concentrator of the distiller was constructed with 32 plane rectangular mirrors; the heat absorber cavity was made with a rectangular blackened aluminum tube 1 m long and installed 2.5 m over the plane of mirrors. The Fresnel linear distiller was installed at the University of Lima and experimental tests were performed during no cloudy summer days. There were measured ambient temperature, heat absorber cavity temperature, radiant flux and fresh water volume. From this, it was obtained a production of 0.89 liters/hour and 0.79 L/m 2 , and it was calculated a total performance of 34.5% in desalting sea water. Finally, it is presented a comparison between Fresnel linear distiller (FLD) and parabolic trough distiller (PTD) with similar dimensions and characteristics. It is obtained that the last one produced almost 32% more fresh water than the former, but at the same time, the FLD is almost 20% cheaper than PTD. However, water cost production with both distillers using is almost the same. (author)

  6. Membrane separation systems---A research and development needs assessment

    Energy Technology Data Exchange (ETDEWEB)

    Baker, R.W. (Membrane Technology and Research, Inc., Menlo Park, CA (USA)); Cussler, E.L. (Minnesota Univ., Minneapolis, MN (USA). Dept. of Chemical Engineering and Materials Science); Eykamp, W. (California Univ., Berkeley, CA (USA)); Koros, W.J. (Texas Univ., Austin, TX (USA)); Riley, R.L. (Separation Systems Technology, San Diego, CA (USA)); Strathmann, H. (Fraunhofer-Institut fuer Grenzflaech

    1990-04-01

    Industrial separation processes consume a significant portion of the energy used in the United States. A 1986 survey by the Office of Industrial Programs estimated that about 4.2 quads of energy are expended annually on distillation, drying and evaporation operations. This survey also concluded that over 0.8 quads of energy could be saved in the chemical, petroleum and food industries alone if these industries adopted membrane separation systems more widely. Membrane separation systems offer significant advantages over existing separation processes. In addition to consuming less energy than conventional processes, membrane systems are compact and modular, enabling easy retrofit to existing industrial processes. The present study was commissioned by the Department of Energy, Office of Program Analysis, to identify and prioritize membrane research needs in light of DOE's mission. Each report will be individually cataloged.

  7. Driving Force Based Design of Cyclic Distillation

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Fjordbak; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2017-01-01

    with mixed phase feeds. A range of binary test cases, benzene toluene, methanol water, and ethanol water, are evaluated. The advantage of the design approach in cyclic distillation is shown to be analogous to the advantages obtained in conventional continuous distillation, including a minimal utility...

  8. Azo dye removal in a membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor

    International Nuclear Information System (INIS)

    Cui, Dan; Guo, Yu-Qi; Cheng, Hao-Yi; Liang, Bin; Kong, Fan-Ying; Lee, Hyung-Sool; Wang, Ai-Jie

    2012-01-01

    Highlights: ► A membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor was developed. ► Alizarin Yellow R as the mode of azo dyes was efficiently converted to p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA). ► PPD and 5-ASA were further oxidized in a bio-contact oxidation reactor. ► The mechanism of UBER for azo dye removal was discussed. - Abstract: Azo dyes that consist of a large quantity of dye wastewater are toxic and persistent to biodegradation, while they should be removed before being discharged to water body. In this study, Alizarin Yellow R (AYR) as a model azo dye was decolorized in a combined bio-system of membrane-free, continuous up-flow bio-catalyzed electrolysis reactor (UBER) and subsequent aerobic bio-contact oxidation reactor (ABOR). With the supply of external power source 0.5 V in the UBER, AYR decolorization efficiency increased up to 94.8 ± 1.5%. Products formation efficiencies of p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA) were above 90% and 60%, respectively. Electron recovery efficiency based on AYR removal in cathode zone was nearly 100% at HRTs longer than 6 h. Relatively high concentration of AYR accumulated at higher AYR loading rates (>780 g m −3 d −1 ) likely inhibited acetate oxidation of anode-respiring bacteria on the anode, which decreased current density in the UBER; optimal AYR loading rate for the UBER was 680 g m −3 d −1 (HRT 2.5 h). The subsequent ABOR further improved effluent quality. Overall the Chroma decreased from 320 times to 80 times in the combined bio-system to meet the textile wastewater discharge standard II in China.

  9. Azo dye removal in a membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Dan; Guo, Yu-Qi; Cheng, Hao-Yi; Liang, Bin; Kong, Fan-Ying [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 202 Haihe Road, Harbin 150090 (China); Lee, Hyung-Sool [Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West Waterloo, Ontario, Canada N2L 3G1 (Canada); Wang, Ai-Jie, E-mail: waj0578@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 202 Haihe Road, Harbin 150090 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer A membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor was developed. Black-Right-Pointing-Pointer Alizarin Yellow R as the mode of azo dyes was efficiently converted to p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA). Black-Right-Pointing-Pointer PPD and 5-ASA were further oxidized in a bio-contact oxidation reactor. Black-Right-Pointing-Pointer The mechanism of UBER for azo dye removal was discussed. - Abstract: Azo dyes that consist of a large quantity of dye wastewater are toxic and persistent to biodegradation, while they should be removed before being discharged to water body. In this study, Alizarin Yellow R (AYR) as a model azo dye was decolorized in a combined bio-system of membrane-free, continuous up-flow bio-catalyzed electrolysis reactor (UBER) and subsequent aerobic bio-contact oxidation reactor (ABOR). With the supply of external power source 0.5 V in the UBER, AYR decolorization efficiency increased up to 94.8 {+-} 1.5%. Products formation efficiencies of p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA) were above 90% and 60%, respectively. Electron recovery efficiency based on AYR removal in cathode zone was nearly 100% at HRTs longer than 6 h. Relatively high concentration of AYR accumulated at higher AYR loading rates (>780 g m{sup -3} d{sup -1}) likely inhibited acetate oxidation of anode-respiring bacteria on the anode, which decreased current density in the UBER; optimal AYR loading rate for the UBER was 680 g m{sup -3} d{sup -1} (HRT 2.5 h). The subsequent ABOR further improved effluent quality. Overall the Chroma decreased from 320 times to 80 times in the combined bio-system to meet the textile wastewater discharge standard II in China.

  10. Determination of styrene migration from food-contact polymers into margarine, using azeotropic distillation and headspace gas chromatography.

    Science.gov (United States)

    Varner, S L; Breder, C V; Fazio, T

    1983-09-01

    Migration studies were conducted to determine the quantity of styrene that migrates from polymers into fatty foods, specifically margarine. Azeotropic distillation was used to isolate styrene from the margarine. Headspace gas chromatography with a Chromosorb 104 column and a flame ionization detector was used for quantitation. The quantitation limit for the method was about 25 ppb (wt/wt) styrene in margarine. On the average, greater than 90% of the styrene was recovered. Several commercial margarines were examined. The method and results of the migration studies are presented. There was no detectable migration of styrene into margarine.

  11. Method of distilling machine-cut peat and other finely divided material

    Energy Technology Data Exchange (ETDEWEB)

    1942-03-03

    Apparatus arrangement is given for dry distillation of machine-cut peat and similar materials in particle or powder form, consisting of a tunnel oven through which the material is led and in which it is heated by help of the gases generated in the process. These gases are brought to circulate through the interior of the oven and heat exchangers installed outside the oven, are flushed by hot combustion gases. Through the tunnel oven a mounted turnable shaft is provided with paddles which lift the material and let it fall to make the particles of material get good contact with the circulating gases without offering too much resistance to the flow of the gases.

  12. Membrane processes in biotechnology: an overview.

    Science.gov (United States)

    Charcosset, Catherine

    2006-01-01

    Membrane processes are increasingly reported for various applications in both upstream and downstream technology, such as the established ultrafiltration and microfiltration, and emerging processes as membrane bioreactors, membrane chromatography, and membrane contactors for the preparation of emulsions and particles. Membrane systems exploit the inherent properties of high selectivity, high surface-area-per-unit-volume, and their potential for controlling the level of contact and/or mixing between two phases. This review presents these various membrane processes by focusing more precisely on membrane materials, module design, operating parameters and the large range of possible applications.

  13. A thermodynamic approach to choosing pervaporatives membranes

    Directory of Open Access Journals (Sweden)

    Mahacine Amrani

    2006-09-01

    Full Text Available This work describes separating a mixture of several components obtained as a product of methyl polymethyl metha- crylate (PMMA thermo-degradation. It was aimed at purifying methyl methacrylate monomer (MMA obtained by 95% mass thermal degradation to reach 99.5% maximum pervaporation concentration. This work studied the theory of pervaporation and applying the main thermodynamic criteria for choosing suitable polymer membranes for separating the MMA/PRP/ISB mixture. Such thermodynamic criteria were based on monomer interaction with and solubility on the membrane. The advantage of using this separation technique lies mainly in the fact that this method has low energy consumption compared to other processes, such as distillation or crystallisation.

  14. A Modelling Framework for Conventional and Heat Integrated Distillation Columns

    DEFF Research Database (Denmark)

    Bisgaard, Thomas; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2013-01-01

    of hydrocarbons such as separations of equimolar mixtures of benzene/toluene or propane/propene described by simple models, a generic, modular, model framework is presented in this work. At present, the framework is able to describe a conventional distillation column, a mechanical vapor recompression column......Diabatic operation of distillation columns can lead to signicant reductions in energy utilization and operation cost compared to conventional (adiabatic) distillation columns, at an expense of an increased complexity of design and operation. The earliest diabatic distillation conguration dates back...... to the late 70s, and various dierent congurations have appeared since. However, at present, no full-scale diabatic distillation columns are currently operating in the industry. Current studies related to alternative distillation congurations report very dierent gures for potential energy savings which...

  15. Transient behavior of enrichment of tritium water in adsorption-distillation column

    International Nuclear Information System (INIS)

    Fukada, Satoshi

    2006-01-01

    Enrichment of tritium in an adsorption-distillation column was experimentally investigated under the two processes of simple distillation and total-reflux distillation. Adsorption of water on silica-gel pellets enhanced the total isotope separation factor in the water distillation column. The transient behavior of tritium enrichment was analyzed using material balance equations of tritium and water in each cell with a height corresponding to HETP. The experimental transient behavior was well simulated by the material balance equations with additional assumptions on vapor and liquid flow rates regardless of the different processes of simple distillation and total-reflux distillation. (author)

  16. RECENT PROGRESS OF OXYGEN/NITROGEN SEPARATION USING MEMBRANE TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    K. C. CHONG

    2016-07-01

    Full Text Available The oxygen-enriched air is highly demanded for various industrial applications such as medical, chemical and enhanced combustion processes. The conventional oxygen/nitrogen production is either cryogenic distillation or pressure swing adsorption (PSA. Both of these techniques possess the production capability of 20 to 300 tonnes of oxygen per day and oxygen purity of more than 95%. However, these techniques are energy intensive. Alternatively, membrane technology is an emerging technology in gas separation as it requires low energy consumption and relatively moderate production volume, if compared to the conventional gas production techniques. These advantages have spurred much interest from industries and academics to speed up the commercial viability of the O2/N2 separation via membrane technology. In this review, the conventional and membrane technologies in O2/N2 separation, as well as recent development of membrane fabrication techniques and materials are reviewed. The latest membrane performance in O2/N2 separation is also tabulated and discussed.

  17. Process and apparatus to distil petroleum. Verfahren und Vorrichtung zur Erdoel-Destillation

    Energy Technology Data Exchange (ETDEWEB)

    Buchenau, R.; Fauser, F.; Fischer, W.

    1982-12-23

    In a process to distil petroleum the raw petroleum is distilled in the first instance at atmospheric pressure to separate the low-boiling components and subsequently under vacuum to separate the remaining components. The vacuum distillation is carried out as a flash distillation using a shortway distiller.

  18. Teaching and learning distillation in chemistry laboratory courses

    Science.gov (United States)

    van Keulen, Hanno; Mulder, Theo H. M.; Goedhart, Martin J.; Verdonk, Adri H.

    This study investigates the problems chemistry majors have with learning distillation in traditional chemistry laboratory courses. Using an interpretive cyclic research design, we collected and interpreted data, mainly in the form of observation notes and transcriptions of the discourse that takes place during laboratory courses. It was found that students experience numerous problems; these are described and interpreted. We summarize students' problems in four categories: (a) students use an independent component conception; (b) they have insufficient understanding of the properties of vapor; (c) they regard distillation from a physical point of view; and (d) they do not have a practical understanding of thermodynamics. The main origin of these problems was found to lie with the traditional curriculum structure. Lecture courses and textbooks treat distillation in a generalized and decontextualized way, whereas decisions in actual distillations are always based on contextual features. It was found that textbooks and teachers often do not discriminate carefully and explicitly among five different contexts for distillation: organic synthesis, chemical analysis, analytical chemistry, physical chemistry, and preparation of products. Students take the generalized concepts at face value and apply them to all distillations regardless of context. They cannot interpret their observations or make reasoned decisions based on the theoretical framework of a specific context.Received: 2 May 1994; Revised: 14 December 1994;

  19. An Investigation of Low Biofouling Copper-charged Membranes

    Science.gov (United States)

    Asapu, Sunitha

    with increased biofouling resistance. The goal of this project was to develop low-biofouling nanofiltration cellulose acetate (CA) membranes through functionalization with metal chelating ligands charged with biocidal metal ions, i.e. copper ions. To this end, glycidyl methacrylate (GMA), an epoxy, was used to attach a chelating agent, iminodiacetic acid (IDA) to facilitate the charging of copper to the membrane surface. Both CA and CA-GMA membranes were cast using the phase-inversion method. The CA-GMA membranes were then charged with copper ions to make them low biofouling. Pore size distribution analysis of CA and copper charged membranes were conducted using various molecular weights of polyethylene glycol (PEG). CA and copper-charged membranes were characterized using Fourier Transform Infrared (FTIR), contact angle to measure hydrophilicity changes, and using scanning electron microscope (SEM) coupled with X-ray energy dispersive spectroscopy EDS to monitor copper leaching. Permeation experiments were conducted with distilled (DI) water, protein solutions, and synthetic brackish water containing microorganisms. The DI water permeation of the copper-charged membranes was initially lower than the CA membranes. The membranes were then subjected to bovine serum albumin (BSA) and lipase filtration. The copper-charged membranes showed higher pure water flux values for both proteins as compared to CA membranes. The rejection of BSA and lipase was the same for both the copper charged and CA membranes. The filtration with the synthetic brackish water showed that copper-charged membranes had higher flux values as compared to CA membranes, and biofouling analysis showed more bacteria on the CA membranes as compared to copper-charged membranes. Therefore, the copper-charged membranes made here have shown a potential to be used as low-biofouling membranes in the future.

  20. Mitofilin complexes : conserved organizers of mitochondrial membrane architecture

    NARCIS (Netherlands)

    Zerbes, Ralf M.; van der Klei, Ida J.; Veenhuis, Marten; Pfanner, Nikolaus; van der Laan, Martin; Bohnert, Maria

    2012-01-01

    Mitofilin proteins are crucial organizers of mitochondrial architecture. They are located in the inner mitochondrial membrane and interact with several protein complexes of the outer membrane, thereby generating contact sites between the two membrane systems of mitochondria. Within the inner

  1. Recycling of Waste Acetone by Fractional Distillation

    Science.gov (United States)

    Weires, Nicholas A.; Johnston, Aubrey; Warner, Don L.; McCormick, Michael M.; Hammond, Karen; McDougal, Owen M.

    2011-01-01

    Distillation is a ubiquitous technique in the undergraduate organic chemistry curriculum; the technique dates back to ca. 3500 B.C.E. With the emergence of green chemistry in the 1990s, the importance of emphasizing responsible waste management practices for future scientists is paramount. Combining the practice of distillation with the message…

  2. Some remarks on the carrier distillation method; Quelques remarques sur la methode 'carrier distillation'

    Energy Technology Data Exchange (ETDEWEB)

    Avni, R; Chaput, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    The method described by SCRIBNER and MULLIN makes possible the spectrographic analysis of the refractory oxides of uranium and plutonium. It uses a distillation of the elements which is more or less selective. The influence of the carrier is the subject of as many hypotheses as there are parameters involved in the process. The measurements of the arc temperature carried out on the leading edges of the vibration bands and of certain copper lines have made it possible to show the influence of the nature of the carrier and to establish a relationship between the values of the excitation potentials of the atoms and the temperatures produced. Further, this result makes it possible to explain certain contradictions between the principle of a fractional distillation in the arc which is incompatible with the refractory properties of certain elements and their spectrographic sensitivity. (author) [French] La methode decrite par SCRIBNER et MULLIN permet l'analyse spectrographique des oxydes refractaires d'uranium et de plutonium. Elle fait appel a une distillation plus ou moins selective des elements. L'influence de l'entraineur est l'objet d'aussi nombreuses hypotheses que les parametres lies au phenomene. Les mesures de la temperature de l'arc, effectuees sur les tetes de bandes de vibration du cyanogene et certaines raies du cuivre ont permis de montrer l'influence de la nature de l'entraineur et de trouver une relation entre les valeurs des potentiels d'excitation des atomes et les temperatures produites. En outre, ce resultat permet d'expliquer certaines contradictions entre le principe d'une distillation fractionnee dans l'arc incompatible avec les proprietes refractaires de certains elements et leur sensibilite spectrographique. (auteur)

  3. Towards energy efficient distillation technologies – Making the right choice

    International Nuclear Information System (INIS)

    Kiss, Anton A.; Flores Landaeta, Servando J.; Infante Ferreira, Carlos A.

    2012-01-01

    In spite of claiming around half of the operational costs of chemical plants, distillation is still the most popular separation technology. Distillation has low thermodynamic efficiency, requiring the input of high quality energy in the reboiler – while rejecting a similar amount of heat at lower temperature, in the condenser. Several heat pump concepts have been proposed to upgrade that thermal energy and reduce the consumption of valuable utilities. Under certain conditions, the energy savings of heat pump assisted distillation is usually around 20–50%. This study proposes a novel selection scheme of energy efficient distillation technologies, with a special focus on heat pumps. The most promising technologies selected are vapor compression, mechanical or thermal vapor recompression, absorption, compression–resorption and thermo-acoustic heat pumps, multi-effect distillation, heat integrated distillation column, cyclic distillation, Kaibel and dividing-wall column. The scheme considers as the main selection criteria the type of separation tasks, product flow and specifications, operating pressure, difference in boiling points, reboiler duty and its temperature level. Moreover, this scheme is very practical, allowing major time and resources savings in the design of eco-efficient processes. -- Highlights: ► Heat pump assisted distillation with energy savings of 20–50%. ► Novel and practical selection scheme of energy efficient distillation technologies. ► Evaluation of promising technologies: VC, MVR, TVR, AHP, CHRP, TAHP, HIDiC, DWC, CyDist. ► Selection criteria include: ΔT b , ΔT lift , P, T reb , Q reb , volatility. ► Design of eco-efficient processes with high COP, and lower TIC and TAC.

  4. Polymeric membranes containing silver salts for propylene/propane separation

    Directory of Open Access Journals (Sweden)

    L. D. Pollo

    2012-06-01

    Full Text Available The separation of olefin/paraffin mixtures is one of the most important processes of the chemical industry. This separation is typically carried out by distillation, which is an energy and capital intensive process. One promising alternative is the use of facilitated transport membranes, which contain specific carrier agents in the polymer matrix that interact reversibly with the double bond in the olefin molecule, promoting the simultaneous increase of its permeability and selectivity. In this study, polyurethane (PU membranes were prepared using two different silver salts (triflate and hexafluorantimonate. The membranes were structurally characterized and their performance for the separation of propylene/propane mixtures was evaluated. The results of the characterization analyses indicated that the triflate salt was the most efficient carrier agent. The membranes containing this salt showed the best performance, reaching an ideal selectivity of 10 and propylene permeability of 188 Barrer.

  5. A review of the FT distillate pathway in GHGenius

    International Nuclear Information System (INIS)

    2006-01-01

    Fischer-Tropsch (FT) distillates products are now used throughout the world as a commercial fuel. However, lifecycle greenhouse gas (GHG) emissions from FT distillates fuels are higher than diesel fuel produced from crude oil. This paper provided details of a lifecycle analysis of FT distillates pathways created for GHGenius, a model used to analyze emissions from a variety of combustion sources. The study examined values reported in tests conducted by major oil and gas operators and described the conversion technologies typically used at FT distillates production facilities. Summaries of reports on FT distillates emissions were also provided. Three primary factors were identified that contributed to different results reported for FT distillates emissions: (1) the efficiency of the conversion process; (2) the allocation procedure used in the conventional oil refinery for the emissions of individual products; and (3) the emissions associated with natural gas production. The GHGenius model was used to quantify the impact of the 3 main factors. An alternative system expansion methodology was used to compare crude oil diesel pathways with a high efficiency, low gas leak scenario in order to achieve high values reported by some oil and gas operators. 5 refs., 5 tabs., 5 figs

  6. Microstructural Engineering and Architectural Design of Metal-Organic Framework Membranes.

    Science.gov (United States)

    Liu, Yi; Ban, Yujie; Yang, Weishen

    2017-08-01

    In the past decade, a huge development in rational design, synthesis, and application of molecular sieve membranes, which typically included zeolites, metal-organic frameworks (MOFs), and graphene oxides, has been witnessed. Owing to high flexibility in both pore apertures and functionality, MOFs in the form of membranes have offered unprecedented opportunities for energy-efficient gas separations. Reports on the fabrication of well-intergrown MOF membranes first appeared in 2009. Since then there has been tremendous growth in this area along with an exponential increase of MOF-membrane-related publications. In order to compete with other separation and purification technologies, like cryogenic distillation, pressure swing adsorption, and chemical absorption, separation performance (including permeability, selectivity, and long-term stability) of molecular sieve membranes must be further improved in an attempt to reach an economically attractive region. Therefore, microstructural engineering and architectural design of MOF membranes at mesoscopic and microscopic levels become indispensable. This review summarizes some intriguing research that may potentially contribute to large-scale applications of MOF membranes in the future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Purification of simple substances by distillation with impurity hydrothermal oxidation

    International Nuclear Information System (INIS)

    Kalashnik, O.N.; Nisel'son, L.A.

    1987-01-01

    A possibility of applying distillation method in water vapours for purification of simple substances from impurities is studied. Based on thermodynamic analysis of interaction processes in E-H 2 O system, conducted using a computer, it is as certained that SS, Se, Te, As, Cd, Hg can be purified from the majority of the impurities analysed by distillation in a water vapour flow. Behaviour of Zn, C, Ge, Al, Sb characteristic impurities under cadmium, arsenic and tellurium distillation is studied. Experiments on cadmium, arsenic and tellurium purification have confirmed, that distillation with hydrothermal oxidation of Zn, C, Ge impurities sometimes appears to be a more effective method as compared to distillation in a hydrogen flow

  8. A Modeling Framework for Conventional and Heat Integrated Distillation Columns

    DEFF Research Database (Denmark)

    Bisgaard, Thomas; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2013-01-01

    In this paper, a generic, modular model framework for describing fluid separation by distillation is presented. At present, the framework is able to describe a conventional distillation column and a heat-integrated distillation column, but due to a modular structure the database can be further...

  9. Renormalizing Entanglement Distillation

    Science.gov (United States)

    Waeldchen, Stephan; Gertis, Janina; Campbell, Earl T.; Eisert, Jens

    2016-01-01

    Entanglement distillation refers to the task of transforming a collection of weakly entangled pairs into fewer highly entangled ones. It is a core ingredient in quantum repeater protocols, which are needed to transmit entanglement over arbitrary distances in order to realize quantum key distribution schemes. Usually, it is assumed that the initial entangled pairs are identically and independently distributed and are uncorrelated with each other, an assumption that might not be reasonable at all in any entanglement generation process involving memory channels. Here, we introduce a framework that captures entanglement distillation in the presence of natural correlations arising from memory channels. Conceptually, we bring together ideas from condensed-matter physics—ideas from renormalization and matrix-product states and operators—with those of local entanglement manipulation, Markov chain mixing, and quantum error correction. We identify meaningful parameter regions for which we prove convergence to maximally entangled states, arising as the fixed points of a matrix-product operator renormalization flow.

  10. Distilling carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Garrow, J R

    1921-04-16

    To obtain an increased yield of by-products such as oils, ammonia, and gas from coal, oil shale, wood, peat, and the like by low and medium temperature processes, the requisite quantity of hot producer gas from a gas producer, is caused to travel, without ignition, through the material as it passes in a continuous manner through the retort so that the sensible heat of the producer gas is utilized to produce distillation of the carbonaceous material, the gases passing to a condenser, absorption apparatus, and an ammonia absorber respectively. In a two-stage method of treatment of materials such as peat or the like, separate supplies of producer gas are utilized for a preliminary drying operation and for the distillation of the material, the drying receptacle and the retort being joined together to render the process continuous. The gas from the drying receptacle may be mixed with the combined producer and retort gas from the retort, after the hydrocarbon oils have deen removed therefrom.

  11. Aromatically enhanced pear distillates from blanquilla and conference varieties using a packed column.

    Science.gov (United States)

    Arrieta-Garay, Yanine; García-Llobodanin, Laura; Pérez-Correa, José Ricardo; López-Vázquez, Cristina; Orriols, Ignacio; López, Francisco

    2013-05-22

    Pear distillates are generally produced from the Bartlett variety because of its rich aroma. In this study, a chemical and sensorial comparative examination of pear distillates from the three main varieties grown in Spain (Bartlett, Blanquilla, and Conference) using two distillation systems (copper Charentais alembic and packed column) was undertaken. Volatile compounds were identified by gas chromatography to differentiate the spirits according to pear variety and distillation method. The Bartlett distillates from both distillation systems possessed higher ethyl ester and acetate and lower cis-3-hexen-1-ol and 1-hexanol concentrations. Despite these differences, a sensory analysis panel could distinguish only the Bartlett alembic distillate from the alembic distillates of the other varieties. In contrast, the panel rated the packed-column distillates equally. Therefore, less aromatic pear varieties can be used to produce distillates with aromatic characteristics similar to those of the Bartlett variety if a suitable distillation process is used.

  12. Design of Unconstrained DMC to Improve the Distillate Product Purity of the Distillation Column

    Directory of Open Access Journals (Sweden)

    Bhat Vinayambika S.

    2016-01-01

    Full Text Available This paper demonstrates the use of unconstrained Dynamic Matrix Control (DMC to control the process transfer function with time delay. The selection of tuning parameter is challenging task in predictive control algorithm. The DMC scheme is designed and it is used here to control the process transfer function, First Order Plant with Dead Time (FOPDT model. Here, one manipulated variable (reflux and one controlled variable (distillate is considered for the implementation. The algorithm significantly controls the reflux to improve the distillate product purity. The simulation is done using MATLAB m-file. Both servo and regulatory responses were obtained. The simulation result validates the effectiveness of the proposed algorithm.

  13. Analytical determination of distillation boundaries for ternary azeotropic systems

    OpenAIRE

    Marcilla Gomis, Antonio; Reyes Labarta, Juan Antonio; Velasco, Raúl; Serrano Cayuelas, María Dolores; Olaya López, María del Mar

    2009-01-01

    A new straight forward algorithm to calculate distillation boundaries in ternary azeotropic systems has been developed. The proposed method allows, using cubic splines, the calculation of distillation trajectories and the calculation of that corresponding to the searched distillation boundaries. The algorithm is applied to 4 ternary liquid-vapour systems to test its validity. Vicepresidency of Research (University of Alicante) and Generalitat Valenciana (GV/2007/125)

  14. Graph Modelling Approach: Application to a Distillation Column

    DEFF Research Database (Denmark)

    Hovelaque, V.; Commault, C.; Bahar, Mehrdad

    1997-01-01

    Introduction, structured systems and digraphs, distillation column model, generic input-output decoupling problem, generic disturbance rejection problem, concluding remarks.......Introduction, structured systems and digraphs, distillation column model, generic input-output decoupling problem, generic disturbance rejection problem, concluding remarks....

  15. Dry-distillation of experimental animal wastes containing radioisotopes

    International Nuclear Information System (INIS)

    Miyatake, Hideo; Saito, Kazumi; Kurihara, Norio

    1988-01-01

    Mice were dry-distilled at 800deg C for 10 min, after [ 32 P]orthophosphate or L-[4,5- 3 H]leucine was intraperitoneally administered. Phosphorus-32 was quantitatively recovered in the residual solid, whereas 95% of 3 H was found in the distillate (condensed water). When 14 C (L-[U- 14 C]malic acid or L-[U- 14 C]leucine) was administered to mice and they were dry-distilled, 14 C-radioactivity was distributed into two fractions; residual solid and exhaust gas. In these cases, the recovery percentage of 14 C in residual solid was not very high but increased as the treating temperature decreased. It reached about 40% of the administered 14 C at 400deg C for 120 min. By the dry-distillation of animals, their weight was reduced to about 10% in every animal tested (mice, rats and rabbits). The volume was reduced to about 20% in cases of mice and rats, and about 30% in case of rabbits. It was concluded that the dry-distillation can be useful as a pre-treatment for disposal of animal wastes containing radioisotopes. (author)

  16. Separation of H-D mixtures by cryogenic distillation

    International Nuclear Information System (INIS)

    Luo Yangming; Gu Mei; Wang Heyi; Liu Jun; Fu Zhonghua; Xia Xiulong; Liu Yunnu; Weng Kuiping; Xie Bo; Ren Xingbi

    2007-01-01

    In this paper, separation of hydrogen-deuterium mixtures were performed on a cryogenic distillation apparatus. The results show that the D/H ratio in the reboiler reduced to 1.27x10 -2 at 120h with a flow flux of 5mol/h of the gas mixture in D/H ratio of 1.4xl0 -4 . The enrichment effect increased apparently with D/H ratio of the feeding gas. However, the deuterium content in the top of distillation column increased with the deuterium content in the reboiler, and the de-deuterium efficiencies decreased. In the full reflux experiment, the de-deuterium efficiency increased with heating power of the reboiler, and the inside pressure in the distillation column increased, too. It was necessary that suitable heating power should be chosen in order to control operation pressure in the cryogenic distillation process. (authors)

  17. Structural Decoupling and Disturbance Rejection in a Distillation Column

    DEFF Research Database (Denmark)

    Bahar, Mehrdad; Jantzen, Jan; Commault, C.

    1996-01-01

    Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references.......Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references....

  18. Effective As(III) Removal by A Multi-Charged Hydroacid Complex Draw Solute Facilitated Forward Osmosis-Membrane Distillation (FO-MD) Processes

    KAUST Repository

    Ge, Qingchun

    2016-01-29

    © 2016 American Chemical Society. Effective removal of As(III) from water by an oxalic acid complex with the formula of Na3[Cr(C2O4)3] (Na-Cr-OA) is demonstrated via an forward osmosis-membrane distillation (FO-MD) hybrid system in this study. Na-Cr-OA first proved its superiority as a draw solute with high water fluxes and negligible reverse fluxes in FO, then a systematic investigation of the Na-Cr-OA promoted FO process was conducted to ascertain the factors in As(III) removal. Relatively high water fluxes of 28 LMH under the FO mode and 74 LMH under the pressure retarded osmosis (PRO) mode were achieved when using a 1000 ppm As(III) solution as the feed and 1.0 M Na-Cr-OA as the draw solution at 60 °C. As(III) removal with a water recovery up to 21.6% (FO mode) and 48.3% (PRO mode) were also achieved in 2 h. An outstanding As(III) rejection with 30-3000 μg/L As(III) in the permeate was accomplished when As(III) feed solutions varied from 5 × 104 to 1 × 106 μg/L, superior to the best FO performance reported for As(III) removal. Incorporating MD into FO not only makes As(III) removal sustainable by reconcentrating the Na-Cr-OA solution simultaneously, but also reduces the As(III) concentration below 10 μg/L in the product water, meeting the WHO standard.

  19. Effective As(III) Removal by A Multi-Charged Hydroacid Complex Draw Solute Facilitated Forward Osmosis-Membrane Distillation (FO-MD) Processes

    KAUST Repository

    Ge, Qingchun; Han, Gang; Chung, Neal Tai-Shung

    2016-01-01

    © 2016 American Chemical Society. Effective removal of As(III) from water by an oxalic acid complex with the formula of Na3[Cr(C2O4)3] (Na-Cr-OA) is demonstrated via an forward osmosis-membrane distillation (FO-MD) hybrid system in this study. Na-Cr-OA first proved its superiority as a draw solute with high water fluxes and negligible reverse fluxes in FO, then a systematic investigation of the Na-Cr-OA promoted FO process was conducted to ascertain the factors in As(III) removal. Relatively high water fluxes of 28 LMH under the FO mode and 74 LMH under the pressure retarded osmosis (PRO) mode were achieved when using a 1000 ppm As(III) solution as the feed and 1.0 M Na-Cr-OA as the draw solution at 60 °C. As(III) removal with a water recovery up to 21.6% (FO mode) and 48.3% (PRO mode) were also achieved in 2 h. An outstanding As(III) rejection with 30-3000 μg/L As(III) in the permeate was accomplished when As(III) feed solutions varied from 5 × 104 to 1 × 106 μg/L, superior to the best FO performance reported for As(III) removal. Incorporating MD into FO not only makes As(III) removal sustainable by reconcentrating the Na-Cr-OA solution simultaneously, but also reduces the As(III) concentration below 10 μg/L in the product water, meeting the WHO standard.

  20. Distilling solid carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, H; Laing, B

    1926-12-04

    In the distillation of solid carbonaceous materials with by-product recovery by direct heating with a gas such as water gas, producer gas, or combustion gas which is passed in counter-flow to the materials, the volume of the gas used is such as to lower the vapor tension of the volatiles to enable the oil vapor to be liberated at temperatures not exceeding 450 to 500/sup 0/C and so that the gaseous mixture may be cooled to from 80 to 100/sup 0/C without causing the highest boiling oil fraction to condense. Coking coals may be subjected to a preliminary heat treatment with gases containing an oxygen content of from 2 to 8 percent to reduce their coking properties, and oxygen may be added to the heating gases to assist the polymerization of resinous bodies. Lubricating oil may be obtained by treating the primary oil with caustic soda to remove tar acids, refining the residue with sulfuric acid, distilling off 25 percent of the refined oil and passing the remainder through a filter press at -5/sup 0/C to extract the paraffin wax. The residue of wax-free oil is distilled to yield a lubricating oil which at normal temperatures has a static coefficient of friction of from .1 to .185. Other specifications are referred to.

  1. Distillation of bituminous substances

    Energy Technology Data Exchange (ETDEWEB)

    du Buisson, M A.B.B.

    1845-06-23

    New and improved methods are described for the distillation of bituminous schistus and other bituminous substances, as well as for the purification, rectification, and preparation necessary for the employment of the productions obtained by such distillation for various useful purposes. This invention consists, first, in the arrangement and construction of furnace or apparatus for the distillation of schistus, and (any) other bituminous rocks. This furnace is made of circular brick-work, and is provided with the requisite number of fires placed round the circumference. The retort is of a conical or funnel shape, and when ready for use, has the appearance of one inverted cone being placed within a larger cone, in such a manner as to leave a space between the two cones for the reception of the schistus. Both cones are capable of being closed at their apexes, and their mouths, which are placed upwards, are connected together, and hermetically closed by a flat ring. The flame draft is caused to impinge against the lower portion of the outer cone and ascending, turns over the upper edge and descends within the inner cone to the mouth of the chimney, which is placed in the interior, and as low as may be convenient. A third cone is so placed within the inner cone as to cause the flame draft, in its descent, to bind against the surface of the retort.

  2. 27 CFR 24.290 - Removal of wine as distilling material.

    Science.gov (United States)

    2010-04-01

    ... or the distilled spirits plant. (b) Special natural wine. Unmarketable special natural wine may be removed to a distilled spirits plant for use as distilling material in the production of wine spirits (but... removal. If wine spirits produced from special natural wine contain any flavor characteristics of the...

  3. Process and apparatus to analyze high-boiling products by distillation

    Energy Technology Data Exchange (ETDEWEB)

    Goupil, J.; Mouton, M.; Fischer, W.

    1982-05-19

    In the described process to analyze high-boiling petroleum products by distillation, contents of these products with atmospheric boiling points above 500/sup 0/C can be isolated as distillates. For this purpose the continuous shortway distillation process is employed and at least a part of the components of the apparatus which serve to introduce the raw product are heated seperately and held at different temperatures. The raw product is distributed on the combustion surface of the shortway distiller by a roller wiping system.

  4. Hybrid and Mixed Matrix Membranes for Separations from Fermentations.

    Science.gov (United States)

    Davey, Christopher John; Leak, David; Patterson, Darrell Alec

    2016-02-29

    Fermentations provide an alternative to fossil fuels for accessing a number of biofuel and chemical products from a variety of renewable and waste substrates. The recovery of these dilute fermentation products from the broth, however, can be incredibly energy intensive as a distillation process is generally involved and creates a barrier to commercialization. Membrane processes can provide a low energy aid/alternative for recovering these dilute fermentation products and reduce production costs. For these types of separations many current polymeric and inorganic membranes suffer from poor selectivity and high cost respectively. This paper reviews work in the production of novel mixed-matrix membranes (MMMs) for fermentative separations and those applicable to these separations. These membranes combine a trade-off of low-cost and processability of polymer membranes with the high selectivity of inorganic membranes. Work within the fields of nanofiltration, reverse osmosis and pervaporation has been discussed. The review shows that MMMs are currently providing some of the most high-performing membranes for these separations, with three areas for improvement identified: Further characterization and optimization of inorganic phase(s), Greater understanding of the compatibility between the polymer and inorganic phase(s), Improved methods for homogeneously dispersing the inorganic phase.

  5. Thermoelectric integrated membrane evaporation water recovery technology

    Science.gov (United States)

    Roebelen, G. J., Jr.; Winkler, H. E.; Dehner, G. F.

    1982-01-01

    The recently developed Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES) offers a highly competitive approach to water recovery from waste fluids for future on-orbit stations such as the Space Operations Center. Low power, compactness and gravity insensitive operation are featured in this vacuum distillation subsystem that combines a hollow fiber membrane evaporator with a thermoelectric heat pump. The hollow fiber elements provide positive liquid/gas phase control with no moving parts other than pumps and an accumulator, thus solving problems inherent in other reclamation subsystem designs. In an extensive test program, over 850 hours of operation were accumulated during which time high quality product water was recovered from both urine and wash water at an average steady state production rate of 2.2 pounds per hour.

  6. Input-Output Decoupling of a Distillation Column LV-Configuration

    DEFF Research Database (Denmark)

    Yazdi, H.; Jørgensen, Sten Bay; Bahar (fratrådt), Mehrdad

    1996-01-01

    Introduction, digraph approach, distillation column, digraph analysis, solution analysis, discussion and conclusion, references.......Introduction, digraph approach, distillation column, digraph analysis, solution analysis, discussion and conclusion, references....

  7. 27 CFR 28.301 - Loss of distilled spirits in transit.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Loss of distilled spirits in transit. 28.301 Section 28.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND....301 Loss of distilled spirits in transit. The tax on distilled spirits withdrawn without payment of...

  8. Rhamnolipid produced by Pseudomonas aeruginosa USM-AR2 facilitates crude oil distillation.

    Science.gov (United States)

    Asshifa Md Noh, Nur; Al-Ashraf Abdullah, Amirul; Nasir Mohamad Ibrahim, Mohamad; Ramli Mohd Yahya, Ahmad

    2012-01-01

    A biosurfactant-producing and hydrocarbon-utilizing bacterium, Pseudomonas aeruginosa USM-AR2, was used to assist conventional distillation. Batch cultivation in a bioreactor gave a biomass of 9.4 g L(-1) and rhamnolipid concentration of 2.4 g L(-1) achieved after 72 h. Biosurfactant activity (rhamnolipid) was detected by the orcinol assay, emulsification index and drop collapse test. Pretreatment of crude oil TK-1 and AG-2 with a culture of P. aeruginosa USM-AR2 that contains rhamnolipid was proven to facilitate the distillation process by reducing the duration without reducing the quality of petroleum distillate. It showed a potential in reducing the duration of the distillation process, with at least 2- to 3-fold decreases in distillation time. This is supported by GC-MS analysis of the distillate where there was no difference between compounds detected in distillate obtained from treated or untreated crude oil. Calorimetric tests showed the calorie value of the distillate remained the same with or without treatment. These two factors confirmed that the quality of the distillate was not compromised and the incubation process by the microbial culture did not over-degrade the oil. The rhamnolipid produced by this culture was the main factor that enhanced the distillation performance, which is related to the emulsification of hydrocarbon chains in the crude oil. This biotreatment may play an important role to improve the existing conventional refinery and distillation process. Reducing the distillation times by pretreating the crude oil with a natural biosynthetic product translates to energy and cost savings in producing petroleum products.

  9. Evaluation of Controller Tuning Methods Applied to Distillation Column Control

    DEFF Research Database (Denmark)

    Nielsen, Kim; W. Andersen, Henrik; Kümmel, Professor Mogens

    A frequency domain approach is used to compare the nominal performance and robustness of dual composition distillation column control tuned according to Ziegler-Nichols (ZN) and Biggest Log Modulus Tuning (BLT) for three binary distillation columns, WOBE, LUVI and TOFA. The scope of this is to ex......A frequency domain approach is used to compare the nominal performance and robustness of dual composition distillation column control tuned according to Ziegler-Nichols (ZN) and Biggest Log Modulus Tuning (BLT) for three binary distillation columns, WOBE, LUVI and TOFA. The scope...

  10. Method of distilling solid materials, such as shale

    Energy Technology Data Exchange (ETDEWEB)

    Ramen, A

    1917-09-04

    A method of distilling compact materials, such as shales, containing volatile matter, is characterized by heating the material in an oven or other apparatus or in a section or zone of same in the presence of some condensable gas (such as steam) which is indifferent to the vapors distillated during the heating of the material. The gas together with these products is conducted through a condensation apparatus, containing water or some other liquid, where the volatile matters are condensed. The steam which is produced in the gas regenerator is, after preheating, forced through the hot remaining residue from the distillation either in the same retort or in another retort in order to heat further this residue for the purpose of making it possible for the steam, by being forced through freshly charged material in the first oven or apparatus to bring about its distillation. The patent contains ten additional claims.

  11. Method of distillation of sulfurous bituminous shales

    Energy Technology Data Exchange (ETDEWEB)

    Hallback, A J.S.; Bergh, S V

    1918-04-22

    A method of distillation of sulfur-containing bituminous shales is characterized by passing the hot sulfur-containing and oil-containing gases and vapors formed during the distillation through burned shale containing iron oxide, so that when these gases and vapors are thereafter cooled they will be, as far as possible, free from sulfur compounds. The patent contains six more claims.

  12. Honeywell Cascade Distiller System Performance Testing Interim Results

    Science.gov (United States)

    Callahan, Michael R.; Sargusingh, Miriam

    2014-01-01

    The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, distillation systems have been actively pursued as one of the technologies for water recovery. The Cascade Distillation System (CDS) is a vacuum rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. The CDS was previously under development through Honeywell and NASA. In 2009, an assessment was performed to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. Based on the results of this testing, an expert panel concluded that the CDS showed adequate development maturity, TRL-4, together with the best product water quality and competitive weight and power estimates to warrant further development. The Advanced Exploration Systems (AES) Water Recovery Project (WRP) worked to address weaknesses identified by The Panel; namely bearing design and heat pump power efficiency. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades. The CDS will also have been challenged with ISS analog waste streams and a subset of those being considered for Exploration architectures. This paper details interim results of the AES WRP CDS performance testing.

  13. Chemical profile of sugarcane spirits produced by double distillation methodologies in rectifying still

    Directory of Open Access Journals (Sweden)

    André Ricardo Alcarde

    2011-06-01

    Full Text Available The objective of this study was to determine the chemical profile of sugarcane spirits produced by different double distillation methodologies in rectifying still. Fermented sugarcane juice was distilled in rectifying still according to three double distillation methodologies: the methodology used for cognac production; the methodology used for whisky production; and the 10-80-10 percentage composition methodology, referring to the volumes of head, heart and tail of the distillate fractions from the second distillation. For comparison purposes, a simple distilled spirit was also produced. The distillates were analyzed for concentrations of ethanol, copper, volatile acidity, furfural and hydroxymethylfurfural, aldehydes, esters, methanol and higher alcohols. The spirits were also evaluated on the sensory attributes of aroma, taste and preference. Compared to simple distillation, double distillation improved the chemical quality of the spirits, since it has reduced the concentrations of acids, aldehydes, esters, methanol, higher alcohols and, consequently, their coefficient of congeners. Regardless of the methodology employed, the double distillation improved the sensory quality of the spirits since they obtained higher sensory acceptance in relation to spirits produced by simple distillation. Among double distilled spirits, the one produced according to whisky methodology obtained the best scores from appraisers on the aroma and flavor parameters and it was also the most preferred.

  14. Solvent distillations studies for a reprocessing plant

    International Nuclear Information System (INIS)

    Ginisty, C.; Guillaume, B.

    1989-01-01

    The substantial amounts of solvent used in large reprocessing plants are such that considerable care must be paid to solvent management to limit the production of organic wastes. The installation of intensive treatment by chemical regeneration serves to increase the service life of the solvent. General solvent management, combined with a distillation unit under reduced pressure also helps to recycle the two components of the solvent at a low activity level. Distillation also serves to remove the heavy degradation products that are generally responsible for poor hydraulic behavior and for the holdup of radioactive products such as plutonium, zirconium and ruthenium. From the safety standpoint, the flashpoint of the distilled diluent tends to rise. It can therefore be recycled without risk

  15. Vacuum distillation/vapor filtration water recovery

    Science.gov (United States)

    Honegger, R. J.; Neveril, R. B.; Remus, G. A.

    1974-01-01

    The development and evaluation of a vacuum distillation/vapor filtration (VD/VF) water recovery system are considered. As a functional model, the system converts urine and condensates waste water from six men to potable water on a steady-state basis. The system is designed for 180-day operating durations and for function on the ground, on zero-g aircraft, and in orbit. Preparatory tasks are summarized for conducting low gravity tests of a vacuum distillation/vapor filtration system for recovering water from urine.

  16. The applicability of radiotracers for the investigation of the distillation of hydrocarbons

    International Nuclear Information System (INIS)

    Graczyk, J.; Iller, E.

    1976-01-01

    The use of radioactive tracers provide valuable methods for the investigation of distillation processes and have been applied to determine the characteristics of material streams, the dynamics of flowing phases and the composition in various parts of the distillation equipment. A method is proposed for testing individual radiotracers emplozemployed for the investigation of the distillation of hydrocarbons. The method consists in laboratory-scale distillation of a tracer together with a multicomponent hydrocarbon mixture, namely a gasoline fraction. The purification efficiency, distillation characteristics, and effective radiochemical purity of several tracers (reactor activated bromobenzene and synthesized C 3 H 7 82 Br, C 4 H 9 82 Br, C 5 H 11 82 Br) have been investigated. The distillation characteristics of bromohydrocarbons labelled with 82 Br and selected hydrocarbons tagged with 14 C (benzene and cumene) have been compared. The radiotracers investigated were employed for the determination of the hydrodynamic parameters of hydrocarbon distillation in laboratory packed columns and a commercial distillation tower. (author)

  17. Modeling and analysis of conventional and heat-integrated distillation columns

    DEFF Research Database (Denmark)

    Bisgaard, Thomas; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2015-01-01

    A generic model that can cover diabatic and adiabatic distillation column configurations is presented, with the aim ofproviding a consistent basis for comparison of alternative distillation column technologies. Both a static and a dynamic formulation of the model, together with a model catalogue...... consisting of the conventional, the heat-integrated and the mechanical vapor recompression distillation columns are presented. The solution procedure of the model is outlined and illustrated in three case studies. One case study being a benchmark study demonstrating the size of the model and the static...... properties of two different heat-integrated distillation column (HIDiC) schemes and the mechanical vapor recompression column. The second case study exemplifies the difference between a HIDiC and a conventional distillation column in the composition profiles within a multicomponent separation, whereas...

  18. 27 CFR 19.65 - Experimental distilled spirits plants.

    Science.gov (United States)

    2010-04-01

    ... spirits plants. 19.65 Section 19.65 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Administrative and Miscellaneous Provisions Activities Not Subject to This Part § 19.65 Experimental distilled spirits plants. The...

  19. RECENT PROGRESS OF OXYGEN/NITROGEN SEPARATION USING MEMBRANE TECHNOLOGY

    OpenAIRE

    K. C. CHONG; S. O. LAI; H. S. THIAM; H. C. TEOH; S. L. HENG

    2016-01-01

    The oxygen-enriched air is highly demanded for various industrial applications such as medical, chemical and enhanced combustion processes. The conventional oxygen/nitrogen production is either cryogenic distillation or pressure swing adsorption (PSA). Both of these techniques possess the production capability of 20 to 300 tonnes of oxygen per day and oxygen purity of more than 95%. However, these techniques are energy intensive. Alternatively, membrane technology is an emerging technology...

  20. Improvement of Egyptian vacuum distillates by urea dewaxing

    Directory of Open Access Journals (Sweden)

    Ehssan M.R. Nassef

    2015-09-01

    Full Text Available The dewaxing of paraffinic lube stocks is an essential step in the production of lubricants to improve the operability of machines especially in winter. The present work deals with study of the urea dewaxing process of two types of Egyptian vacuum distillates. The effect of different compositions of methanol to water saturated with urea and yield of the oil, percent of wax, pour point, refractive index, viscosity, viscosity index and specific gravity of the oil produced from the two types of distillates (I and II were evaluated. The operating conditions of the urea adduct formation with n-paraffins using methanol to water mixture achieved the best pour point at −3.88 °C from an initial temperature of 4.4 °C for distillate I at (25/75 methanol to water. At the same ratio of methanol to water the best specific gravity of oil produced changed from 0.865 to 0.867, with viscosity index of 80. Percent yield of 50% for oil and percent wax of 50% were obtained. Results for distillate II, of higher specific gravity, are comparatively higher than those for distillate I. Experiments were carried out at room temperature.