Sample records for packed distillation column

  1. Application of optimal adaptive generalized predictive control to a packed distillation column

    Microsoft Academic Search

    S Karacan; H Hapo?lu; M Alpbaz

    2001-01-01

    In this work, optimal operating conditions for a packed distillation column and optimal adaptive generalized predictive control (OA-GPC) were investigated. Thus, the dynamic and steady-state properties of the packed distillation column distilling methanol–water mixture were observed experimentally and theoretically. Mathematical models for the packed distillation column were solved with orthogonal collocation on finite elements. Optimal operating conditions of the system

  2. Generalized predictive control to a packed distillation column for regulatory problems

    Microsoft Academic Search

    S. Karacan; H. Hapo?lu; M. Alpbaz

    1998-01-01

    In this work, adaptive Generalized Predictive Control (GPC) was investigated at the optimal operating conditions for a pilot plant binary packed distillation column. The studieswere made experimentally and theoretically. The dynamic behavior of the distillation column has been simulated using backmixing model and solved by utilizing Hermite Polynomials within the finite element procedure.The control of the overhead product temperature was

  3. APPLICATION OF MULTIVARIABLE GENERALIZED PREDICTIVE CONTROL TO A PACKED DISTILLATION COLUMN

    Microsoft Academic Search

    S. KARACAN; Y. CABBAR; C. E. BALAS; M. ALPBAZ

    1999-01-01

    The present work deals with the application of Multivariate Generalized Predictive Control (MGPC) systems to a packed distillation column. The steady-state and dynamic behaviour of the system have been simulated using two film plug flow model. The model solutions have been obtained employing orthogonal collocation on finite element. The Jacobi polynomials within the finite element procedure was tested to determine

  4. Counter-current operation of structured catalytically packed distillation columns: pressure drop, holdup and mixing

    Microsoft Academic Search

    J. Ellenberger; R. Krishna

    1999-01-01

    Structured packed columns, in which the catalyst particles are enclosed within wire gauze envelopes (“sandwiches”) are promising reactor configurations for reactive distillation and hydroconversions. By allowing preferential channels for the gas and liquid phases, counter-current operation is achieved even for millimeter sized catalyst particles without the problem of flooding. This paper reports the results of a comprehensive experimental study of

  5. Distillation columns containing structured packings: A comprehensive model for their performance. 2: Mass-transfer model

    Microsoft Academic Search

    J. Antonio Rocha; Jose L. Bravo; James R. Fair

    1996-01-01

    This is the second part of a two-part paper dealing with the fluid mechanics and mass transfer in structured packings for distillation column service. The first part elucidated pressure drop, flooding, and liquid holdup. The second part covers the generation of effective interfacial area and provides a general correlation for predicting the mass-transfer efficiency as a function of surface type,

  6. Distillation columns containing structured packings: A comprehensive model for their performance. 1. Hydraulic models

    Microsoft Academic Search

    J. Antonio Rocha; Jose L. Bravo; James R. Fair

    1993-01-01

    A mechanistically-based model has been developed to aid the analysis and design of distillation columns containing structured packings of the corrugated plate type. The model encompasses the important, and related, parameters of liquid holdup, pressure drop, flooding, and mass-transfer efficiency. Since it deals with the countercurrent contacting of liquid with gas or vapor, the model may also be applied to

  7. Energy Saving in Distillation Using Structured Packing and Vapor Recompression

    E-print Network

    Hill, J.H.

    "Distillation is a big consumer of energy in process plant operations. A first step to energy cost savings is the use of high efficiency structured packing in place of trays or dumped packings in conventionally operated distillation columns. Larger...

  8. Utilization of Structured Packing for Energy Savings in Distillation and Absorption Columns

    E-print Network

    Berven, O. J.; Howard, W. E.

    . As Figure No. 4 demonstrates, over 30% of the tray area is occupied by the bubbl e caps and downcomers, resulti ng ina much higher vapor or gas velocity at the deck of the tray. This, in turn, causes more entrainment, especially in those sections where... the ori9ina1 sieve trays. The revamped col umn can run as high as 210% of the Case 1 loads. Table No.8 summarizes the cost savings derived from this particular revamp when trays and structured packing are compa red at Case 1 rates. Based on $4. 00 per...

  9. Column Initialization 1 Initializing Distillation Column Models 1

    E-print Network

    Dundee, University of

    Column Initialization 1 Initializing Distillation Column Models 1 Roger Fletcher \\Lambda with the optimisation of distillation column models by non­ linear programming are considered. The paper presents of the distillation column model. A certain limiting case of the column model is examined, that of infinite reflux

  10. Process Svstems Enaineerina Instability of Distillation Columns

    E-print Network

    Skogestad, Sigurd

    Process Svstems Enaineerina , Instability of Distillation Columns Elling W. Jacobsen and Sigurd recognized, distillation columns, operating with reflux and boilup as independent inputs, may have The dynamic behavior of distillation columns has been stud- ied quite extensively over the past decades

  11. Microfabricated packed gas chromatographic column

    DOEpatents

    Kottenstette, Richard; Matzke, Carolyn M.; Frye-Mason, Gregory C.

    2003-12-16

    A new class of miniaturized gas chromatographic columns has been invented. These chromatographic columns are formed using conventional micromachining techniques, and allow packed columns having lengths on the order of a meter to be fabricated with a footprint on the order of a square centimeter.

  12. Tritium Isotope Separation Using Adsorption-Distillation Column

    SciTech Connect

    Fukada, Satoshi [Kyushu University (Japan)

    2005-07-15

    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, {alpha}{sub H-T}{sup equi}. The adsorption action improved not only HETP but also {alpha}{sub H-T}{sup 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.

  13. Optimization of Cryogenic Air Separation Distillation Columns

    Microsoft Academic Search

    Yu Zhu; Xinggao Liu; Zhiyong Zhou

    2006-01-01

    Cryogenic air separation distillation columns are widely used in industry, which consume a large energy and need to produce a huge amount of need of nitrogen, oxygen and argon products with high purity. Of pervious optimal researches on cryogenic distillation column, few considers argon column due to the complex degree of process. In this work, rigorous optimization model of cryogenic

  14. Optimal design of thermally coupled distillation columns

    Microsoft Academic Search

    G. Duennebier; Constantinos C. Pantelides

    1999-01-01

    This paper considers the optimal design of thermally coupled distillation columns and dividing wall columns using detailed column models and mathematical optimization. The column model used is capable of describing both conventional and thermally coupled columns, which allows comparisons of different structural alternatives to be made. Possible savings in both operating and capital costs of up to 30% are illustrated

  15. The Scaleup of Structured Packing from Distillation Pilot Plant Testing to Commercial Application

    E-print Network

    Berven, O. J.; Ulowetz, M. A.

    The Scaleup of Structured Packing From Distillation Pilot Plant Testing to Commercial Application O. Jeffrey'Berven and Michael A. Ulowetz Koch Engineering Company, Inc. Wichita, Kansas Structured packing is being utilized more and more... in the process industry for increased efficiency, greater capacity, and energy savings in distillation columns. Pilot plant testing of the actual chemical system using commercially available structured packing is invaluable, but years of experience in pilot...

  16. Heat Exchanger Technologies for Distillation Columns

    E-print Network

    Polley, G. T.

    Heat Exchanger Technologies for Distillation Columns G.T.Polley Pinchtechnology.com In this paper we look at the challenges that improvements in energy efficiency of distillation systems presents the heat exchanger designer. We examine... each type of exchanger in turn. Heat exchanger size is minimised if the temperature driving force is maximised. The design should therefore seek to minimise the temperature changes during phase change. So, streams that are being condensed are kept...

  17. EXPERIMENTAL SIMULATION OF DISTILLATION COLUMN PROFILE MAPS

    E-print Network

    Skogestad, Sigurd

    , Johannesburg, in fulfillment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2007 #12 for the degree of Doctor of Philosophy in the University of the Witwatersrand, Johannesburg. It has not been used to predict the composition changes in the distillation column but also to determine

  18. Gas flow distribution in packed columns

    Microsoft Academic Search

    Rumen Darakchiev; Chavdar Dodev

    2002-01-01

    The distribution of gas flow over the cross section of packed columns depends on the manner of gas flow feeding, on packing type, packing arrangement, and internal devices in the apparatus body. Various types of gas inlet devices are studied in order to estimate their ability for creation of uniform velocity profiles. The gas flow uniformity is characterized by the

  19. Model Predictive Control of a Kaibel Distillation Column

    E-print Network

    Skogestad, Sigurd

    Model Predictive Control of a Kaibel Distillation Column Martin Kvernland Ivar Halvorsen Sigurd (e-mail: skoge@ntnu.no) Abstract: This is a simulation study on controlling a Kaibel distillation column with model predictive control (MPC). A Kaibel distillation column has several advantages compared

  20. Active constraint regions for optimal operation of distillation columns

    E-print Network

    Skogestad, Sigurd

    Active constraint regions for optimal operation of distillation columns Magnus G. Jacobsen the control structure of distillation columns, with optimal operation in mind, it is important to know how for distillation columns change with variations in energy cost and feed flow rate. The production of the most

  1. Method for packed column separations and purifications

    DOEpatents

    Holman, David A. (Richland, WA); Bruckner-Lea, Cynthia J. (Richland, WA); Brockman, Fred J. (Kennewick, WA); Chandler, Darrell P. (Richland, WA)

    2006-08-15

    The invention encompasses a method of packing and unpacking a column chamber. A mixture of a fluid and a matrix material are introduced through a column chamber inlet so that the matrix material is packed within a column chamber to form a packed column. The column chamber having the column chamber inlet or first port for receiving the mixture further has an outlet port and an actuator port. The outlet port is partially closed for capturing the matrix material and permitting the fluid to flow therepast by rotating relative one to the other of a rod placed in the actuator port. Further rotation relative one to the other of the rod and the column chamber opens the outlet and permits the matrix material and the fluid to flow therethrough thereby unpacking the matrix material from the column chamber.

  2. Final Report, Distillation Column Flooding Predictor

    SciTech Connect

    George E. Dzyacky

    2003-05-31

    The Flooding Predictor is an advanced process control strategy comprising a patented pattern-recognition methodology that identifies pre-flood patterns discovered to precede flooding events in distillation columns. The grantee holds a U.S. patent on the modeling system. The technology was validated at the Separations Research Program, The University of Texas at Austin under a grant from the U. S. Department of Energy, Inventions & Innovation Program. Distillation tower flooding occurs at abnormally high vapor and/or liquid rates. The loss in tray efficiencies is attributed to unusual behavior of liquid inventories inside the column leading to conditions of flooding of the space in between trays with liquid. Depending on the severity of the flood condition, consequences range from off spec products to equipment damage and tower shutdown. This non-intrusive pattern recognition methodology, processes signal data obtained from existing column instrumentation. Once the pattern is identified empirically, it is modeled and coded into the plant's distributed control system. The control system is programmed to briefly "unload" the tower each time the pattern appears. The unloading takes the form of a momentary reduction in column severity, e.g., decrease bottom temperature, reflux or tower throughput. Unloading the tower briefly at the pre-flood state causes long-term column operation to become significantly more stable - allowing an increase in throughput and/or product purity. The technology provides a wide range of value between optimization and flooding. When a distillation column is not running at capacity, it should be run in such a way ("pushed") that optimal product purity is achieved. Additional benefits include low implementation and maintenance costs, and a high level of console operator acceptance. The previous commercial applications experienced 98% uptime over a four-year period. Further, the technology is unique in its ability to distinguish between different flooding mechanisms within the same tower, e.g., liquid and jet flooding.

  3. Effects of system densities on distillation column performance

    SciTech Connect

    Fasesan, S.O.; Sanni, S.A.; Taiwo, E.A. [Obafemi Awolowo Univ., Ile-Ife (Nigeria). Dept. of Chemical Engineering

    1998-06-01

    Distillation experiments were carried out on three binary systems (ethanol-butanol, ethanol-propan-2-ol, and propan-2-ol-butanol) in a 0.1-m internal diameter glass column packed with 8 mm diameter Raschig rings. The experiments were performed under total reflux conditions and at atmospheric pressure. The data collected on column performance showed that performance declined with increasing average bulk liquid density. The results also lend credence to earlier reports on the behavior of column performance with respect to component concentration in the feed mixtures. The system densities of the three binary systems were measured at four different temperatures, 30, 40, 50, and 60 C. The data were compared with the predicted data of Yen-Woods and Multifluid models. The accuracy of the predictions of the Yen-Woods model was rather poor while that of the Multifluid model was very encouraging.

  4. DYNAMICS AND CONTROL OF DISTILLATION COLUMNS A CRITICAL SURVEY

    E-print Network

    Skogestad, Sigurd

    DYNAMICS AND CONTROL OF DISTILLATION COLUMNS ­ A CRITICAL SURVEY Sigurd Skogestad \\Lambda Chemical, Identification and Control, 18, 177­217, 1997. Abstract Distillation column dynamics and control has been viewed these, the feasibility of using the distillate­bottom structure for control (which was believed

  5. DYNAMICS AND CONTROL OF DISTILLATION COLUMNS -A CRITICAL SURVEY

    E-print Network

    Skogestad, Sigurd

    DYNAMICS AND CONTROL OF DISTILLATION COLUMNS - A CRITICAL SURVEY Sigurd Skogestad Chemical cation and Control, 18, 177-217, 1997. Abstract Distillation column dynamics and control has been viewed, the feasibility of using the distillate-bottomstructure for control which was believed to be impossible

  6. A Versatile, Automatic Chromatographic Column Packing Device

    ERIC Educational Resources Information Center

    Barry, Eugene F.; And Others

    1977-01-01

    Describes an inexpensive apparatus for packing liquid and gas chromatographic columns of high efficiency. Consists of stainless steel support struts, an Automat Getriebmotor, and an associated three-pulley system capable of 10, 30, and 300 rpm. (MLH)

  7. Continuous and Batch Distillation in an Oldershaw Tray Column

    ERIC Educational Resources Information Center

    Silva, Carlos M.; Vaz, Raquel V.; Santiago, Ana S.; Lito, Patricia F.

    2011-01-01

    The importance of distillation in the separation field prompts the inclusion of distillation experiments in the chemical engineering curricula. This work describes the performance of an Oldershaw column in the rectification of a cyclohexane/n-heptane mixture. Total reflux distillation, continuous rectification under partial reflux, and batch…

  8. Internally Heat-Integrated Distillation Columns: A Review

    Microsoft Academic Search

    M. Nakaiwa; K. Huang; A. Endo; T. Ohmori; T. Akiya; T. Takamatsu

    2003-01-01

    The heat-integrated distillation column to be addressed in this paper is a special distillation column that involves internal heat integration between the whole rectifying and the whole stripping sections. An overview of the research on this process is presented in this work. It covers from the thermodynamic development and evaluations to the practical design and operation investigations for the process.

  9. Intelligent fuzzy supervisory control for distillation columns

    E-print Network

    Santhanam, Srinivasan

    1993-01-01

    Distillation as a separation technique is widely used in the chemical and petroleum industries. With the growth of these industries and the availability of cheap process computing, the interest in more accurate control of the distillation units has...

  10. Future perspectives of using hollow fibers as structured packings in light hydrocarbon distillation

    SciTech Connect

    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 suggests that polypropylene hollow fibers are stable after a long time exposure to C{sub 2} - C{sub 4} mixtures. The effects of packing density on the separation efficiency will be discussed.

  11. Imaging of liquid distribution in reactive distillation packings with a new high-energy x-ray tomograph

    NASA Astrophysics Data System (ADS)

    Toye, D.; Crine, M.; Marchot, P.

    2005-11-01

    We describe a new, high-energy (420 kV), large-scale (0.45 m in diameter, 4 m in height) x-ray tomograph developed to investigate gas and liquid flow through fixed bed like absorption, distillation and reactive distillation columns. The first results obtained with this set-up on test objects (physical phantoms), such as a cylindrical container filled with water or a large diameter structured metallic packing, validate the technique as a quantitative tool for geometrical measurements. Very detailed two-dimensional (2D) and three-dimensional (3D) images of a 0.09 m diameter KATAPAK-SP 12, a reactive distillation packing, are presented. Quantitative information relative to liquid hold-up distribution may be obtained from tomographic imaging performed on an irrigated column packed with this element.

  12. Efficiencies of trays in cryogenic distillation columns

    Microsoft Academic Search

    M. W. Biddulph

    1986-01-01

    This Paper considers the behaviour of the distillation trays in conventional use in cryogenic air separation plants. An earlier study showed that the trays should operate at higher efficiencies than plant experience would indicate. This conclusion was based on the assumption of uniform liquid flow across the trays. In practice, stagnant zones can occur which reduce the efficiency. A study

  13. Miniature Distillation Column for Producing LOX From Air

    NASA Technical Reports Server (NTRS)

    Rozzi, Jay C.

    2006-01-01

    The figure shows components of a distillation column intended for use as part of a system that produces high-purity liquid oxygen (LOX) from air by distillation. (The column could be easily modified to produce high-purity liquid nitrogen.) Whereas typical industrial distillation columns for producing high-purity liquid oxygen and/or nitrogen are hundreds of feet tall, this distillation column is less than 3 ft (less than about 0.9 m) tall. This column was developed to trickle-charge a LOX-based emergency oxygen system (EOS) for a large commercial aircraft. A description of the industrial production of liquid oxygen and liquid nitrogen by distillation is prerequisite to a meaningful description of the present miniaturized distillation column. Typically, such industrial production takes place in a chemical processing plant in which large quantities of high-pressure air are expanded in a turboexpander to (1) recover a portion of the electrical power required to compress the air and (2) partially liquefy the air. The resulting two-phase flow of air is sent to the middle of a distillation column. The liquid phase is oxygen-rich, and its oxygen purity increases as it flows down the column. The vapor phase is nitrogen-rich and its nitrogen purity increases as it flows up the column. A heater or heat exchanger, commonly denoted a reboiler, is at the bottom of the column. The reboiler is so named because its role is to reboil some of the liquid oxygen collected at the bottom of the column to provide a flow of oxygen-rich vapor. As the oxygen-rich vapor flows up the column, it absorbs the nitrogen in the down-flowing liquid by mass transfer. Once the vapor leaves the lower portion of the column, it interacts with down-flowing nitrogen liquid that has been condensed in a heat exchanger, commonly denoted a condenser, at the top of the column. Liquid oxygen and liquid nitrogen products are obtained by draining some of the purified product at the bottom and top of the column, respectively. Because distillation is a mass-transfer process, the purity of the product(s) can be increased by increasing the effectiveness of the mass-transfer process (increasing the mass-transfer coefficient) and/or by increasing the available surface area for mass transfer through increased column height. The diameter of a distillation column is fixed by pressure-drop and mass-flow requirements. The approach taken in designing the present distillation column to be short yet capable of yielding a product of acceptably high purity was to pay careful attention to design details that affect mass-transfer processes.

  14. Packing capilllary electrochromatography columns using vacuum--a preliminary study.

    PubMed

    Qu, Qishu; Hu, Xiaoya; Zhu, Xiashi; Gao, Shanmin; Xu, Qiang; Wang, Yubao; Wang, Xirong

    2004-10-01

    This paper introducesa novel method for packing Capillary Electrochromatography Columns (CEC). Using vacuum packing methodology, silica particles as small as 1 microm were successfully packed into the capillary columns with 75 microm inner diameter. The columns are verystable and show no noticeable loss in efficiency after 200 sample injections. The performance of these vacuum packed capillary columns was evaluated with a mixture of aromatic and non-aromatic compounds. A 24 cm long capillary column can produce peak efficiencies of around 45,000 plates for benzene. PMID:15537081

  15. Experimental results of hydrogen distillation at the low power cryogenic column for the production of deuterium depleted hydrogen

    SciTech Connect

    Alekseev, I.; Fedorchenko, O.; Kravtsov, P.; Vasilyev, A.; Vznuzdaev, M. [Petersburg Nuclear Physics Inst., Leningrad district, Gatchina, 188300 (Russian Federation)

    2008-07-15

    The Deuterium Removal Unit (DRU) has been designed and built at the Petersburg Nuclear Physics Inst. (PNPI) to produce isotopically pure hydrogen with deuterium content less than 1 ppm. The cryogenic distillation column of 2.2 cm inner diameter and 155 cm packing height is the main element of the DRU. Column performances at different hydrogen distillation operating modes have been measured. The height equivalent to theoretical plate (HETP) for the column is 2.2 cm and almost constant over a wide range of vapour flow rates. Deuterium depleted hydrogen with a deuterium content of less than 0.1 ppm was produced in required quantity. (authors)

  16. Air separation process using packed columns for oxygen and argon recovery

    Microsoft Academic Search

    R. M. Thorogood; D. L. Bennett; R. J. Allam; A. L. Prentice; B. K. Dawson

    1989-01-01

    This patent describes an improvement in a process for the separation of mixtures, which comprise oxygen, nitrogen, and argon, by cryogenic distillation in an integrated multi-column distillation system of at least three distillation columns, having a higher pressure column, low pressure column and an argon sidearm column. Wherein the argon sidearm column integrally communicates with the low pressure column. Wherein

  17. T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial

    E-print Network

    Skogestad, Sigurd

    T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial heat integrated distillation column Truls Larsson Sigurd Skogestad ÝDepartment of Chemical. Larsson, S. Skogestad Control of a industrial heat integrated distillation column The process QH column

  18. T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial

    E-print Network

    Skogestad, Sigurd

    T. Larsson, S. Skogestad Control of a industrial heat integrated distillation column Control of a industrial heat integrated distillation column Truls Larsson Sigurd Skogestad y Department of Chemical. Larsson, S. Skogestad Control of a industrial heat integrated distillation column The process Q H column

  19. Behavior of packing materials in axially compressed chromatographic columns

    Microsoft Academic Search

    Djamel E Cherrak; Majed Al-Bokari; Eric C Drumm; Georges Guiochon

    2002-01-01

    The behavior of a packing material (Luna C18 from Phenomenex, Torrance, CA, USA) was studied during the consolidation of a column bed under axial compression stress. The kinetics of this consolidation, the permeability and efficiency of the columns obtained, and the reproducibility of these column properties were measured under different conditions. The consolidation process and the column properties are considerably

  20. Computer Aided Design Module for a Binary Distillation Column

    Microsoft Academic Search

    K. R. Onifade

    A Computer Aided Design (CAD) module was developed for determining some design parameters for a binary distillation column using the Lewis-Sorrel method and Visual Basic. The module made use of a data bank containing physical and thermodynamic properties of 18 substances. A sample design problem was solved using the module. Results from the module and manual calculations were very close.

  1. Energy saving and capital cost evaluation in distillation column sequences with a divided wall column

    Microsoft Academic Search

    Massimiliano Errico; Giuseppe Tola; Ben-Guang Rong; Daniele Demurtas; Ilkka Turunen

    2009-01-01

    The divided wall column (DWC) to separate three components in a single distillation tower is receiving increasing interest in industrial applications due to the potentiality in energy and capital cost savings. In this work, the DWC configurations for the separation of a four components mixture was considered, and 5 different composition cases were analyzed. After selecting the best simple column

  2. Dividing wall columns for heterogeneous azeotropic distillation Quang-Khoa Le1

    E-print Network

    Skogestad, Sigurd

    Dividing wall columns for heterogeneous azeotropic distillation Quang-Khoa Le1 , Ivar J. Halvorsen2 of this work is to implement heterogeneous azeotropic distillation schemes in a dividing wall column (DWC distillation, Petlyuk arrangement, energy saving. 1. Introduction Distillation is one of the most energy

  3. Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad

    E-print Network

    Skogestad, Sigurd

    for heat integrated distillation columns. This work we will look at control of two industrially heat- grated distillation columns will behave differently than two normal heat integrated distillation column on a controllability analysis. Finally nonlinear simulation with a rigorous model confirms our findings. 1 Introduction

  4. Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad

    E-print Network

    Skogestad, Sigurd

    for heat integrated distillation columns. This work we will look at control of two industrially heat­ grated distillation columns will behave differently than two normal heat integrated distillation column on a controllability analysis. Finally nonlinear simulation with a rigorous model confirms our findings. 1 Introduction

  5. THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES WITH APPLICATION TO DISTILLATION COLUMNS

    E-print Network

    Skogestad, Sigurd

    THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES WITH APPLICATION TO DISTILLATION COLUMNS John Morud that a subsystem is in uenced only by its nabor subsystems. An example of such a process is a distillation column in high purity distillation columns; in fact, the magnitude of these time constants may increase

  6. A globally convergent method for finding all steady-state solutions of distillation columns

    E-print Network

    Neumaier, Arnold

    A globally convergent method for finding all steady-state solutions of distillation columns Ali distillation column with 7 steady-states show the robustness of the method. No published software known to the steady-state model of distillation columns as it returns the original system as a single large block

  7. The dos and don'ts of distillation column control Sigurd Skogestad*

    E-print Network

    Skogestad, Sigurd

    The dos and don'ts of distillation column control Sigurd Skogestad* Department of Chemical discusses distillation column control within the general framework of plantwide control. In addition for distillation columns. The standard LV-configuration combined with a fast temperature loop is recommended

  8. THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES --WITH APPLICATION TO DISTILLATION COLUMNS

    E-print Network

    Skogestad, Sigurd

    THE DYNAMIC BEHAVIOR OF CASCADE PROCESSES --WITH APPLICATION TO DISTILLATION COLUMNS John Morud that a subsystem is influenced only by its nabor subsystems. An example of such a process is a distillation column in high purity distillation columns; in fact, the magnitude of these time constants may increase

  9. Comparison of Alternative Control Structures for an Ideal Two-Product Reactive Distillation Column

    E-print Network

    Al-Arfaj, Muhammad A.

    Comparison of Alternative Control Structures for an Ideal Two-Product Reactive Distillation Column distillation columns have been explored in many papers, very few papers have dealt with closed-loop control. Most of these control papers consider reactive distillation columns in which there is only one product

  10. Applying risk assessment principles to a batch distillation column

    SciTech Connect

    Woodward, J.L.; Moosemiller, M.D. [DNV Technica, Columbus, OH (United States)] [DNV Technica, Columbus, OH (United States)

    1996-12-31

    Some distillation columns in the chemical industry are operated in batch mode with a fairly short operating cycle. At the end of each cycle the columns are cooled and recharged. During the cooling cycle, air will be drawn into the column by the action of a vacuum relief valve. Consequently, for a finite portion of the operating cycle a flammable mixture will exist in the column. Here we evaluate the risk posed by such an operation to see if a mitigation measure is justified. We develop a fault tree and estimate the frequency of ignition by all possible ignition sources. By comparing the risk reduction attainable by installing a lightning protection system with that attainable by using an inert blanketing system the lightning protection system is found to be the preferred solution. It provides about the same risk reduction at a lower overall cost. 2 refs., 3 figs., 4 tabs.

  11. A cryogenic distillation column for the XENON1T experiment

    NASA Astrophysics Data System (ADS)

    Rosendahl, S.; Brown, E.; Cristescu, I.; Fieguth, A.; Huhmann, C.; Murra, M.; Weinheimer, C.

    2014-11-01

    The XENON collaboration aims for the direct detection of cold dark matter in form of weakly interacting massive particles (WIMPs). A dual phase time projection chamber filled with liquid xenon is used to detect the WIMP-nucleon interaction. For the next generation experiment XENON1T with an active target mass of 1 ton of xenon, a new distillation column to remove krypton out of xenon to a concentration of < 5 × 10?13 (0.5 ppt) natural krypton in xenon is designed and tested at the Institut für Kernphysik, Universitat Munster. The experimental setup together with two diagnostic tools is presented, as well as one stability test of a 11 hour distillation run at the designed flowrate of 3 kg per hour.

  12. Optimal Operation of a Petlyuk Distillation Column: Energy Savings by Over-fractionating

    E-print Network

    Skogestad, Sigurd

    Optimal Operation of a Petlyuk Distillation Column: Energy Savings by Over-fractionating Vidar Trondheim, Norway Keywords: Distillation, Petlyuk, Divided-wall, Minimum energy Abstract This paper shows the unexpected result that over-fractionating one of the product streams in a Petlyuk distillation column may

  13. Use of Two Distillation Columns in Systems with Maximum Temperature Limitations

    E-print Network

    Gilchrist, James F.

    Use of Two Distillation Columns in Systems with Maximum Temperature Limitations Rebecca H. Masel, Pennsylvania 18015, United States ABSTRACT: Maximum temperature limitations are encountered in distillation of the bottoms product fixes the column base pressure and, hence, the condenser pressure. The distillate

  14. New materials and packing techniques for micro-HPLC packed capillary columns

    Microsoft Academic Search

    A. Cappiello; P. Palma; F. Mangani

    1991-01-01

    Summary  Plastic tubing of polyetheretherketone (PEEK) is used for the preparation of HPLC packed capillary columns. The polymer is\\u000a rigid but not fragile, has great resistance to chemical and physical agents and comes in standard 1\\/16? O.D. These features\\u000a can extend the column lifetime and facilitate the overall employment of HPLC capillary columns. Serial connection of short\\u000a columns is also possible

  15. The development of HPLC columns: Packing structure, column efficiency, stability and standardization

    SciTech Connect

    Unger, K.K.; Hallman, M.; Ranis-Jansen, R. [Johannes Gutenberg-Universitat, Mainz (Germany)

    1995-12-01

    Packing procedures for HPLC columns, such as the slurry technique (analytical columns) and the axial compression technique (preparative columns) have been widely established. However, there is still a lack of fundamental knowledge concerning the actual packing structure of a column and its impact on efficiency and stability. Recently, attempts have been made to model the packing procedure as well as the column bed structure and to apply experimental methods to characterize the assembly of microparticles in a column and the elution profiles in situ. The high reproducibility of commercial HPLC columns with respect to efficiency is mainly due to the substantial improvements made in particle technology, column hardware and optimized column packing procedures. The stability of commercial columns is acceptable but very much dependent on the extent of sample clean-up and the column handling and operation by the user. To validate HPLC methods, a project is planned to establish a C18 reversed phase reference column for standardization and certification in the frame of the EC Programme on {open_quotes}Measurements and Testing{open_quotes}.

  16. Distillation: Energy Savings and Other Benefits From the Use of High Efficiency Packings

    E-print Network

    Bravo, J. L.; Fair, J. R.; Humphrey, J. L.

    DISTILLATION: ENERGY SAVINGS AND OTHER BENEFITS. FROM THE USE OF HIGH-EFFICIENCY PACKINGS -. Jose L. Bravo, James R. Fair, and Jimmy L. Humpnrey The University of Texas at Austin Austin, Texas ABSTRACT A great deal of attention has been... focused lately on the use of high-efficiency packings for distillation applications. This paper discusses benefits that can be derived from the use of these devices. In parti~ular, the reduction in energy requirements for a given separation...

  17. Optimization of a Diabatic Distillation Column with Sequential Heat Edward Steven Jimenez and Peter Salamon*

    E-print Network

    Salamon, Peter

    Optimization of a Diabatic Distillation Column with Sequential Heat Exchangers Edward Steven of Copenhagen, Copenhagen, Denmark Diabatic distillation is a separation process in which heat is transferred is enormous because distillation is the single largest energy degrading unit operation worldwide. Introduction

  18. Integrated Column Designs for Minimum Energy and Entropy Requirements in Multicomponent Distillation

    E-print Network

    Skogestad, Sigurd

    Distillation Ivar J. Halvorsen1 and Sigurd Skogestad Norwegian University of Science and Technology, Department at the Topical conference on Separations Technology, Session 23 - Distillation Modeling and Processes II. 2001 Column Designs for Minimum Energy and Entropy Requirements in Multicomponent Distillation Ivar J

  19. Nonlinear Model Predictive Control of High Purity Distillation Columns for Cryogenic Air Separation

    Microsoft Academic Search

    Zhongzhou Chen; Michael A. Henson; Paul Belanger; Lawrence Megan

    2010-01-01

    High purity distillation columns are critical unit operations in cryogenic air separation plants that supply purified gases to a number of industries. We have developed a nonlinear model predictive control (NMPC) strategy based on the assumption of full-state feedback for a prototypical cryogenic distillation column to allow effective operation over a wide range of plant production rates. The controller design

  20. METHOD TO TEST ISOTOPIC SEPARATION EFFICIENCY OF PALLADIUM PACKED COLUMNS

    SciTech Connect

    Heung, L; Gregory Staack, G; James Klein, J; William Jacobs, W

    2007-06-27

    The isotopic effect of palladium has been applied in different ways to separate hydrogen isotopes for many years. At Savannah River Site palladium deposited on kieselguhr (Pd/k) is used in a thermal cycling absorption process (TCAP) to purify tritium for over ten years. The need to design columns for different throughputs and the desire to advance the performance of TCAP created the need to evaluate different column designs and packing materials for their separation efficiency. In this work, columns with variations in length, diameter and metal foam use, were tested using an isotope displacement method. A simple computer model was also developed to calculate the number of theoretical separation stages using the test results. The effects of column diameter, metal foam and gas flow rate were identified.

  1. Dynamic process simulation of a distillation column on a shared memory parallel processor computer

    SciTech Connect

    Cera, G.D. (Central Research and Development Dept., E.I. du Pont de Nemours and Co., Wilmington, DE (US))

    1988-01-01

    In this study, results of an investigation into applying parallel computing on a shared memory multiprocessor computer to the dynamic process simulation of a distillation column with use of a sequential modular simulator are reported. Two DYFLO process simulation models of distillation columns were parallelized and ported to a BBN Butterfly Parallel Processor computer. Computations were performed with up to 14 concurrently operating processors. General performance aspects of simulation on parallel computers are discussed and speedup as a function of humber of concurrently operating processors is reported for the two distillation column simulations.

  2. Startup of distillation columns using profile position control based on nonlinear wave model

    SciTech Connect

    Han, M.; Park, S. [Chungnam National Univ., Taejon (Korea, Republic of). Chemical Engineering Dept.] [Chungnam National Univ., Taejon (Korea, Republic of). Chemical Engineering Dept.; [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Chemical Engineering Dept.

    1999-04-01

    Startup of distillation columns is a very challenging control problem because of its strong nonlinearity and a wide operating range during the transient period. A nonlinear wave model captures the essential dynamic behavior of the distillation process so that it is possible to deal with the difficulties encountered during startup operation. This paper is concerned with the startup of distillation systems using nonlinear wave model based control developed by Han and Park. This control scheme uses profile positions as controlled variables and is based on the nonlinear wave model by Hwang and generic model control scheme by Lee and Sullivan. It can be applied to a binary or a multicomponent distillation system that can be represented as a pseudobinary. The proposed control scheme is shown by simulation studies to provide a safe and economic startup operation not only for dual composition control of a simple distillation column but also for a complex distillation configuration.

  3. High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns

    E-print Network

    Wisz, M. W.; Antonelli, R.; Ragi, E. G.

    1981-01-01

    Vapor recompression of distillation columns overheads, followed by subsequent condensation in the reboiler results in substantial operating cost savings compared to conventional steam driven reboiler systems. The use of high performance heat...

  4. Catalytic distillation process

    DOEpatents

    Smith, Jr., Lawrence A. (Bellaire, TX)

    1982-01-01

    A method 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.

  5. Catalytic distillation process

    DOEpatents

    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.

  6. Cascaded process model based control: packed absorption column application.

    PubMed

    Govindarajan, Anand; Jayaraman, Suresh Kumar; Sethuraman, Vijayalakshmi; Raul, Pramod R; Rhinehart, R Russell

    2014-03-01

    Nonlinear, adaptive, process-model based control is demonstrated in a cascaded single-input-single-output mode for pressure drop control in a pilot-scale packed absorption column. The process is shown to be nonlinear. Control is demonstrated in both servo and regulatory modes, for no wind-up in a constrained situation, and for bumpless transfer. Model adaptation is demonstrated and shown to provide process insight. The application procedure is revealed as a design guide to aid others in implementing process-model based control. PMID:24176668

  7. MODELING, IDENTIFICATION AND CONTROL, 2000, VOL. 21, NO. 2, 83103 Evaluation of Dynamic Models of Distillation Columns with Emphasis

    E-print Network

    Skogestad, Sigurd

    of Distillation Columns with Emphasis on the Initial Response BERND WITTGENS and SIGURD SKOGESTAD* Keywords: Distillation dynamics, tray hydraulics, experimental response The flow dynamics (tray hydraulics) are of key importance for the initial dynamic response of distillation columns. The most important parameters

  8. Can the Operating Leaves of a Distillation Column Really Be Tshepo S. Modise, Michaela Tapp, Diane Hildebrandt,* and David Glasser

    E-print Network

    Skogestad, Sigurd

    Can the Operating Leaves of a Distillation Column Really Be Expanded? Tshepo S. Modise, Michaela to determine the operation leaves and hence the feasible region for distillation columns operating at a specific distillate and bottoms composition for all possible constant reflux and reboil ratios

  9. Development of dynamic models of reactive distillation columns for simulation and determination of control

    E-print Network

    Chakrabarty, Arnab

    2005-02-17

    to the high octane number of the stream. This gives rise to a challenging problem as the hydrogenation of benzene can also lead to hydrogenation of toluene which is undesirable. The objective of this work is to study a reactive distillation 6 column.................................................................................1 Benzene Hydrogenetation ..............................................................................................5 Description of the Column Under Study........................................................................6 Objective...

  10. Optimal Allocation of Heat Exchanger Inventory in a Serial Type Diabatic Distillation Column

    E-print Network

    Salamon, Peter

    Optimal Allocation of Heat Exchanger Inventory in a Serial Type Diabatic Distillation Column Edward the column . We have previously shown (Jimenez et al. 2003) that optimaloperation of serial heat exchangers total heat exchanger area in different trays and calculate the optimal allocation of a given heat

  11. Chromate transport through columns packed with surfactant-modified zeolite/zero valent iron pellets

    E-print Network

    Li, Zhaohui

    Chromate transport through columns packed with surfactant-modified zeolite/zero valent iron pellets or treated with the cationic surfactant hexadecyltrimethylammonium (HDTMA), was studied at different flow

  12. First Commissioning of a Cryogenic Distillation Column for Low Radioactivity Underground Argon

    E-print Network

    Back, Henning O; Alton, Andrew; Condon, Christopher; de Haas, Ernst; Galbiati, Cristiano; Goretti, Augusto; Hohmann, Tristan; Ianni, Andrea; Kendziora, Cary; Loer, Ben; Montanari, David; Mosteiro, Pablo; Pordes, Stephen

    2012-01-01

    We report on the performance and commissioning of a cryogenic distillation column for low radioactivity underground argon at Fermi National Accelerator Laboratory. The distillation column is designed to accept a mixture of argon, helium, and nitrogen and return pure argon with a nitrogen contamination less than 10 ppm. In the first commissioning, we were able to run the distillation column in a continuous mode and produce argon that is 99.9% pure. After running in a batch mode, the argon purity was increased to 99.95%, with 500 ppm of nitrogen remaining. The efficiency of collecting the argon from the gas mixture was between 70% and 81%, at an argon production rate of 0.84-0.98 kg/day.

  13. First Commissioning of a Cryogenic Distillation Column for Low Radioactivity Underground Argon

    E-print Network

    H. O. Back; T. Alexander; A. Alton; C. Condon; E. de Haas; C. Galbiati; A. Goretti; T. Hohmann; An. Ianni; C. Kendziora; B. Loer; D. Montanari; P. Mosteiro; S. Pordes

    2012-05-01

    We report on the performance and commissioning of a cryogenic distillation column for low radioactivity underground argon at Fermi National Accelerator Laboratory. The distillation column is designed to accept a mixture of argon, helium, and nitrogen and return pure argon with a nitrogen contamination less than 10 ppm. In the first commissioning, we were able to run the distillation column in a continuous mode and produce argon that is 99.9% pure. After running in a batch mode, the argon purity was increased to 99.95%, with 500 ppm of nitrogen remaining. The efficiency of collecting the argon from the gas mixture was between 70% and 81%, at an argon production rate of 0.84-0.98 kg/day.

  14. Integrated Thermal and Hydraulic Analysis of Distillation Columns

    E-print Network

    Samant, K.; Sinclair, I.; Keady, G.

    by assuming that the equilibrium and operating lines coincide at this stage. This approximation takes into account the losses or inefficiencies introduced through practicalities of column design (such as pressure drops, multiple side-products, side strippers... (heating or cooling) ? Side condensing or reboiling An additional capability is provided through exergy analysis. The exergy profiles are plotted by calculating the exergy loss at each stage of the column, and then taking into account all entering...

  15. 3D printed porous media columns with fine control of column packing morphology.

    PubMed

    Fee, Conan; Nawada, Suhas; Dimartino, Simone

    2014-03-14

    In this paper we demonstrate, for the first time, the use of 3D printing (also known as additive manufacturing or rapid prototyping) to create porous media with precisely defined packing morphologies, directly from computer aided design (CAD) models. We used CAD to design perfectly ordered beds with octahedral beads (115 ?m apothem) packed in a simple cubic configuration and monoliths with hexagonal channels (150 ?m apothem) in parallel and herringbone arrangements. The models were then printed by UV curing of acrylonitrile-butadiene-styrene powder layers. Each porous bed was printed at 1.0, 1.5 and 2.0 mL volumes, within a complete column, including internal flow distributors and threaded 10-32 flow connectors. Close replication of CAD models was achieved. The resultant individual octahedral beads were highly uniform in size, with apothems of 113.6±1.9 ?m, while the monolith hexagonal cross-section channels had apothems of 148.2±2.0 ?m. Residence time distribution measurements show that the beds largely behaved as expected from their design void volumes. Radial and fractal flow distributor designs were also tested. The former displayed poor flow distribution in parallel and herringbone pore columns, while the fractal distributors provided uniform flow distribution over the entire cross section. The results show that 3D printing is a feasible method for producing precisely controlled porous media. We expect our approach to revolutionize not only fundamental studies of flow in porous media but methods of chromatography column production. PMID:24529407

  16. Heat and mass transfer model approach to optimum design of cryogenic air separation plant by packed columns with structured packing

    Microsoft Academic Search

    Nobuaki Egoshi; Hiroshi Kawakami; Koichi Asano

    2002-01-01

    A process simulator for design of a cryogenic air separation plant by packed columns with structured packing was developed by use of our heat and mass transfer model. The heat and mass transfer rates were estimated by correlations which were proposed in our previous work (J. Chem. Eng. Japan 33 (2000) 245). Comparison of the predicted separation performance of a

  17. Exact electric field strength over the packed capillary electrochromatography column bed, theoretical considerations and practical determination.

    PubMed

    Guo, Wei; Yang, Changhua; Xu, Bingjiu

    2004-12-01

    On the basis of the experiments, it was proved that Ohm's law holds true in a capillary electrochromatography (CEC) column. By using the additivity of the potential drop over the packed and unpacked sections, the exact values of the electric field strength over the packed CEC column bed were determined experimentally. The ratio of the resistance of packed CEC column sections to that of an open capillary of the same length (Rp/Ro,Lp) were calculated. Some theoretical calculations were made to show how some structural parameters of particle lattice affect the resulting Rp/Ro,Lp value of the column bed formed accordingly. It is suggested that to correctly elucidate the EOF phenomenon in a CEC column, the potential drop over the packed and unpacked column sections, Ep and Eo, should be accounted for respectively, rather than using the average field strength over the total column length. PMID:15628139

  18. On the snap-back behavior of a self-deploying antiprismatic column during packing

    E-print Network

    On the snap-back behavior of a self-deploying antiprismatic column during packing Noémi Friedman a: Available online xxxx Keywords: Snap-back behavior Deployable structure Antiprismatic structure Geometrical packing sequence. The typical equilibrium path in the mast packing sequence is characterized by a snap

  19. Development of a mathematical model of a packed column for benzene removal from salt solutions

    SciTech Connect

    Georgeton, G.K.

    1989-01-01

    A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other locations.

  20. Development of a mathematical model of a packed column for benzene removal from salt solutions

    SciTech Connect

    Georgeton, G.K.

    1989-12-31

    A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other locations.

  1. Design of Extraction Column Methanol Recovery System for the TAME Reactive Distillation Process

    E-print Network

    Al-Arfaj, Muhammad A.

    Design of Extraction Column Methanol Recovery System for the TAME Reactive Distillation Process, Dhahran, 31261, Saudi Arabia Abstract This paper studies the synthesis and the design of methanol recovery that methanol could be recovered completely from the hydrocarbon when 5 equilibrium trays in the extraction

  2. Prediction of the Trayed Distillation Column Mass-Transfer Performance by Neural Networks

    E-print Network

    Eldridge, R. Bruce

    Prediction of the Trayed Distillation Column Mass-Transfer Performance by Neural Networks Eric modeled using a neural network. The database developed by Garcia and Fair (Ind. Eng. Chem. Res. 2000, 39, 1809) was utilized to train and validate the neural network model. The results indicate that

  3. Biocolloid transport in water saturated columns packed with sand

    NASA Astrophysics Data System (ADS)

    Syngouna, V. I.; Chrysikopoulos, C.

    2010-12-01

    Protection of groundwater supplies from microbial contamination necessitates a solid understanding of the factors controlling the migration and retention of pathogenic organisms (biocolloids) in the subsurface. The transport behavior of three waterborne pathogens (Escherichia coli, MS2, and ??174) was investigated using laboratory-scale columns packed with clean quartz sand. Various grain sizes and pore water velocities were examined. Though coliform bacteria and coliphages are used worldwide to indicate fecal pollution of groundwater, the various parameters controlling the transport of Escherichia coli MS2 and ??174 in the subsurface are not fully understood. In this study, the attachment behavior of Escherichia coli, MS2, and ??174 onto ultra-pure quartz sand were evaluated. The mass recoveries of the three biocolloids examined were found to be proportional to the sand size. The observed mass recoveries were in the order: Escherichia coli > ??174 > MS2. To assess the importance of biocolloid attachment, the single collector removal efficiency, and the collision efficiency were quantified using the classical colloid filtration theory. Our results indicate that the secondary energy minimum plays an important role in biocolloid deposition even for smaller biocolloid particles (e.g. viruses).

  4. Modified method to improve the design of Petlyuk distillation columns

    PubMed Central

    2014-01-01

    Background A response surface analysis was performed to study the effect of the composition and feeding thermal conditions of ternary mixtures on the number of theoretical stages and the energy consumption of Petlyuk columns. A modification of the pre-design algorithm was necessary for this purpose. Results The modified algorithm provided feasible results in 100% of the studied cases, compared with only 8.89% for the current algorithm. The proposed algorithm allowed us to attain the desired separations, despite the type of mixture and the operating conditions in the feed stream, something that was not possible with the traditional pre-design method. The results showed that the type of mixture had great influence on the number of stages and on energy consumption. A higher number of stages and a lower consumption of energy were attained with mixtures rich in the light component, while higher energy consumption occurred when the mixture was rich in the heavy component. Conclusions The proposed strategy expands the search of an optimal design of Petlyuk columns within a feasible region, which allow us to find a feasible design that meets output specifications and low thermal loads. PMID:25061476

  5. The setup of an extraction system coupled to a hydrogen isotopes distillation column

    SciTech Connect

    Zamfirache, M.; Bornea, A.; Stefanescu, I.; Bidica, N.; Balteanu, O.; Bucur, C. [INC-DTCI, ICSIRm. Valcea, Uzinei Street 4, Rm. Valcea (Romania)

    2008-07-15

    Among the most difficult problems of cryogenic distillation one stands apart: the extraction of the heavy fraction. By an optimal design of the cycle scheme, this problem could be avoided. A 'worst case scenario' is usually occurring when the extracted fraction consists of one prevalent isotope such as hydrogen and small amounts of the other two hydrogen isotopes (deuterium and/or tritium). This situation is further complicated by two parameters of the distillation column: the extraction flow rate and the hold-up. The present work proposes the conceptual design of an extraction system associated to the cryogenic distillation column used in hydrogen separation processes. During this process, the heavy fraction (DT, T{sub 2}) is separated, its concentration being the highest at the bottom of the distillation column. From this place the extraction of the gaseous phase can now begin. Being filled with adsorbent, the extraction system is used to temporarily store the heavy fraction. Also the extraction system provides samples for the gas Chromatograph. The research work is focused on the existent pilot plant for tritium and deuterium separation from our institute to validate the experiments carried out until now. (authors)

  6. Hydrodynamics and mass transfer coefficients for a modified Raschig ring packed column

    NASA Astrophysics Data System (ADS)

    Mamaliga, I.; Sidor, D.; Condurat, C.; Iacob Tudose, E. T.

    2014-10-01

    The pressure drop, the liquid holdup, as well as the liquid film mass transfer coefficients (kL) for a modified Raschig packing, with turbulence promoters, used in absorption columns, were determined experimentally. The aim of this work is to verify the improved mass transfer properties of this new packing for the randomly and, particularly, for the arranged packed columns. The experiments were performed at gas velocities ranging from 800 to 2,000 m h-1 and liquid velocities scaling between 2.5 and 8.11 m h-1, ranges that cover most of the absorption column operation conditions. Experimental data and correlations for the pressure drop, the liquid holdup and the gas-liquid mass transfer coefficients (kL) for modified Raschig ring packed columns are presented. The influence of the gas and the liquid velocities on the column hydrodynamics and the mass transfer coefficients have been obtained experimentally and also, have been compared with literature data.

  7. Development of a Fritless Packed Column for Capillary Electrochromatography-Mass Spectrometry

    PubMed Central

    Bragg, William; Shamsi, Shahab A.

    2011-01-01

    A novel procedure was developed for the fabrication of a fritless packed column for the coupling of capillary electrochromatography (CEC) to mass spectrometry (MS). The process involved the formation of internal tapers on two separate columns. Once the internal tapers are formed and the columns are packed, the untapered ends of each column were joined together by a commercially available connector. Several advantages of the fritless columns are described. First, the design used here eventually eliminates the need for any frits thus reducing the possibility of bubble formation seen with fritted packed columns. In addition, this is the first report in which the internal tapers are formed at both the inlet and outlet column ends making the fritless CEC-MS column more robust compared to only one report with externally tapered counterparts. Second, a comparison of internally tapered single frit packed CEC-MS (previously developed in our laboratory) column versus fritless CEC-MS column reported here shows that the latter provides better efficiency, suggesting no dead volume with equally good sensitivity and chiral resolution of (±)-aminoglutethimide. The fritless column procedure is universal and was used to prepare a series of columns with a variety of commercially available packing material (mixed mode strong cation exchange, SCX; mixed mode strong anion exchange, SAX; C-18) for the separation and MS detection of short chain non-chromophoric polar amines, long chain nonchromophic anionic surfactant as well as oligomers of non-chromophoric non-ionic surfactants, respectively. The fritless columns showed good intra-day repeatibility and inter-day reproducibility of retention times, chiral and achiral resolutions and peak areas. Very satisfactory column-to-column and operator-to-operator reproducibility was demonstrated. PMID:22035695

  8. Submitted to special issue ChERD. This version revised 22 Nov. 2006 The dos and don'ts of distillation column control

    E-print Network

    Skogestad, Sigurd

    'ts of distillation column control Sigurd Skogestad* Department of Chemical Engineering Norwegian University of Science and Technology N-7491 Trondheim, Norway Abstract The paper discusses distillation column control recommendations to assist the engineer in designing control systems for distillation columns. The standard LV

  9. Evaluation of Packed Columns in Supercritical Extraction Processes

    E-print Network

    Rathkamp, P. J.; Fair, J. R.; Humphrey, J. L.

    on the gas chromatograph. 25...--__--:- ..., System Carbon Dioxide/lsoproponol/Wa1er ? and 0 - Pocked Column (~4 Raschig Rings) 20 ? and a-Spray Column Parameter Is Superficial ~.-. \\ Velocity Of Continuous /. 4.3 .15 Phase (FtlHr) /. Koco (14f... EXTRACTION COlUMN CHROMATOGRAPHIC ANALYSIS SOLVENT TANK Figu~e 1. Supercritical extraction apparatus through the middle. The column contains 12 windows to allOW for visual inspection of phase contacting between the supercritical carbon dioxide...

  10. COMPARISON OF OZONE CONTACTORS FOR MUNICIPAL WASTEWATER EFFLUENT DISINFECTION, PACKED COLUMN VERSUS JET SCRUBBER

    EPA Science Inventory

    Pilot scale investigations were made comparing two ozone contactors, a jet scrubber and a packed column, for ozone utilization and effluent coliform reduction efficiency. The contactors were operated in three phases: (1) Batch operational phase contactors were operated separately...

  11. Estimating vent emissions from a distillation column: An alternative to stack testing

    SciTech Connect

    Dickerson, D.L. Jr. [ERM-Southeast, Charleston, SC (United States)

    1996-12-31

    This technical paper points out the cost-effectiveness and data manageability of material balance over the epidemic use of stack testing in the chemical industry. An example is drawn from a Title V emissions inventory prepared for an international manufacturer of pharmaceuticals and fuel additives. This example case focuses on the use of mass balance to estimate noncondensibles generated by a typical large-scale distillation column. Distillation fundamentals are reviewed, including discussion of relative volatility, x-y and McCabe-Thiele diagrams, and basic sieve tray mechanics. A seemingly complex set of energy and material balance equations is simplified by the application of constant molar overflow. The example case concludes with a calculation of column noncondensibles, and the paper closes with a review of the material balance approach, including its strengths, limitations, and applicability to other unit operations.

  12. Optical resolution HPLC column packings carrying penicillin sulfoxide nucleus. Part I. Polymer synthesis and resolution efficiency

    Microsoft Academic Search

    Y. Saotome; T. Miyazawa; T. Endo

    1989-01-01

    Polyacryl or methacrylamides bearing penicillin sulfoxide skeleton were synthesized. The obtained polymers were coated onto macroporous silica gel and the properties of the prepared packings were investigated. The column packing comprising poly(benzyl 1-oxo-6-methacrylaminopenicillanate) was found to resolve various aromatic racemates.

  13. Geometry and Optimal Packing of Twisted Columns and Filaments

    E-print Network

    Gregory M. Grason

    2015-01-30

    This review presents recent progress in understanding constraints and consequences of close-packing geometry of filamentous or columnar materials possessing non-trivial textures, focusing in particular on the common motifs of twisted and toroidal structures. The mathematical framework is presented that relates spacing between line-like, filamentous elements to their backbone orientations, highlighting the explicit connection between the inter-filament {\\it metric} properties and the geometry of non-Euclidean surfaces. The consequences of the hidden connection between packing in twisted filament bundles and packing on positively curved surfaces, like the Thomson problem, are demonstrated for the defect-riddled ground states of physical models of twisted filament bundles. The connection between the "ideal" geometry of {\\it fibrations} of curved three-dimensional space, including the Hopf fibration, and the non-Euclidean constraints of filament packing in twisted and toroidal bundles is presented, with a focus on the broader dependence of metric geometry on the simultaneous twisting and folded of multi-filament bundles.

  14. Development of chromatofocusing techniques employing mixed-mode column packings for protein separations.

    PubMed

    Guo, Hui; Li, Xiang; Frey, Douglas D

    2014-01-01

    Recent studies reported in the literature using mixed-mode chromatography (MMC) column packings have shown that multiple modes of interactions between the column packing and proteins can be usefully exploited to yield excellent resolution as well as salt-tolerant adsorption of the target protein. In this study, a mixed-mode separation method using commercially available column packings was explored which combines the techniques of hydrophobic-interaction chromatography and chromatofocusing. Two different column packings, one based on mercapto-ethyl-pyridine (MEP) and the other based on hexylamine (HEA) were investigated with regard to their ability to separate proteins when using internally generated, retained pH gradients. The effects of added salt and urea on the behavior of the retained pH gradient and the protein separation achieved when using MMC column packings for chromatofocusing were also investigated. Numerical simulations using methods developed in previous work were shown to agree with experimental results when using reasonable physical parameters. These numerical simulations were also shown to be a useful qualitative method to select the compositions of the starting and elution buffers in order to achieve desired shapes for the pH and ionic strength gradients. The use of the method to fractionate blood serum was explored as a prototype example application. PMID:24296295

  15. Mobility of spiromesifen in packed soil columns under laboratory conditions.

    PubMed

    Mate, Ch Jamkhokai; Mukherjee, Irani; Das, Shaon Kumar

    2014-11-01

    On percolating water equivalent to 1,156 mm of rainfall, spiromesifen formulation did not leach out of 25-cm long columns, and 62.7 % of this was recovered in 5-10-cm soil depth. In columns treated with the analytical grade, 52.40 % of the recovered spiromesifen was confined to 0-5-cm soil depth, with 0.04 % in leachate fraction, suggesting high adsorption in soil. Results revealed that percolating 400 mL of water, residues of enol metabolite of spiromesifen was detected up to 20-25-cm soil layer, with 23.50 % residues of spiromesifen in this layer and 1.73 % in the leachate fraction indicating that metabolite is more mobile as compared to the parent compound. Results suggested a significant reduction in leaching losses of enol metabolite in amended soil columns with 5 % nano clay, farmyard manure (FYM), and vermicompost. No enol spiromesifen was recovered in the leachate in columns amended with nano clay, vermicompost, and FYM; however, 85.30, 70.5, and 65.40 %, respectively, was recovered from 0-5 cm-soil depth of column after percolating water equivalent to 1,156 mm of rainfall. Spiromesifen formulation is less mobile in sandy loam soil than analytical grade spiromesifen. The metabolite, enol spiromesifen, is relatively more mobile than the parent compound and may leach into groundwater. The study suggested that amendments were very effective in reducing the downward mobility of enol metabolite in soil column. Further, it resulted in greater retention of enol metabolite in the amendment application zone. PMID:25060860

  16. Distillation

    NSDL National Science Digital Library

    N/A N/A (None; )

    2005-12-24

    Science in its earliest beginnings consisted of a practice called alchemy. Alchemy includes the study of chemistry, biology, astronomy, spirituality, physics, and art. Distillation or experiments in purification of substances may have been a part of the practice of alchemy.

  17. Penetration of different human pathogenic viruses into sand columns percolated with distilled water, groundwater, or wastewater.

    PubMed Central

    Dizer, H; Nasser, A; Lopez, J M

    1984-01-01

    The adsorption of several enteroviruses and rotavirus SA11 to sand from an aquifer in the Federal Republic of Germany was estimated in sand-filled columns loaded with ca. 10(7) PFU and run at a velocity of 2.5 m/day for 12 h. After either distilled water, groundwater, secondary effluent, or tertiary effluent was percolated, the sand core was slowly extruded out of the column and cut in 1-cm slices. The slices were eluted with nutrient broth, and the amount of viruses in the broth was estimated. The best adsorption was promoted by groundwater and tertiary effluent, followed by distilled water and secondary effluent. Similar experiments, carried out at different percolation rates, indicated that a 50-day underground stay of recharged water probably suffices to eliminate viruses in the groundwater-recharged tertiary effluent. However, when viruses and sand were incubated in the presence of the surfactants sodium dodecyl sulfate, nonyl phenol, dodigen 226, or alkylbenzylsulfonate, the adsorption of the viruses was substantially diminished. Experiments in the presence of nonyl phenol seem to indicate that hydrophobic interactions are involved in the adsorption of viruses to sand. PMID:6324676

  18. Adsorption in columns packed with porous adsorbent particles having partially fractal structures.

    PubMed

    Li, Min; Liapis, Athanasios I

    2013-06-01

    A mathematical model is constructed and solved that could describe the dynamic behavior of the adsorption of a solute of interest in single and stratified columns packed with partially fractal porous adsorbent particles. The results show that a stratified column bed whose length is the same as that of a single column bed, provides larger breakthrough times and a higher dynamic utilization of the adsorptive capacity of the particles than those obtained from the single column bed, and the superior performance of the stratified bed becomes especially more important when the superficial velocity of the flowing fluid stream in the column is increased to accommodate increases in the system throughput. This occurs because the stratified column bed provides larger average external and intraparticle mass transfer and adsorption rates per unit length of packed column. It is also shown that increases in the total number of recursions of the fractal and the ratio of the radii between larger and smaller microspheres that make up the partially fractal particles, increase the intraparticle mass transfer and adsorption rates and lead to larger breakthrough times and dynamic utilization of the adsorptive capacity of the particles. The results of this work indicate that highly efficient adsorption separations could be realized through the use of a stratified column comprised from a practically reasonable number of sections packed with partially fractal porous adsorbent particles having reasonably large (i) total number of recursions of the fractal and (ii) ratio of the radii between larger and smaller microspheres from which the partially fractal particles are made from. It is important to mention here that the physical concepts and modeling approaches presented in this work could be, after a few modifications of the model, applied in studying the dynamic behavior of chemical catalysis and biocatalysis in reactor beds packed with partially fractal porous catalyst particles. PMID:23936911

  19. Final Report - Advanced Hydraulic and Mass Transfer Models for Distillation Column Optimization and Design

    SciTech Connect

    Eldridge, Robert, B.

    2005-10-13

    The project successfully developed a computational fluid dynamics (CFD) based simulation of the hydrodynamics of flow in a commercial structured packing element. This result fulfilled the prime objective of the research program. The simulation utilized commercial CFD code marketed by Fluent Inc. in combination with a novel graphical interface developed by Oak Ridge National Lab. The end product will allow the design of next generation column internals without the need for extensive experimental validation and will expand the fundamental understanding of the vapor-liquid contacting process.

  20. New Generation of Chromatographic Packings and Columns for Determination of Biologically Active Compounds

    Microsoft Academic Search

    Bogus?aw Buszewski; Sylwia Kowalska; Katarzyna Krupczy?ska

    2005-01-01

    Analysis of biologically active substances is particularly important in the pharmaceutical and biomedical area. For separation of polar compounds or complex mixtures by normal (NP) or reversed phase liquid chromatography (RP-HPLC) and\\/or electromigration techniques, it is necessary to apply a new generation of packings and columns with strictly defined properties. It is connected to the definition of chromatographic behavior and

  1. Cotransport of Pseudomonas putida and kaolinite particles through water-saturated columns packed with glass beads

    Microsoft Academic Search

    Ioanna A. Vasiliadou; Constantinos V. Chrysikopoulos

    2011-01-01

    This study is focused on Pseudomonas putida bacteria transport in porous media in the presence of suspended kaolinite clay particles. Experiments were performed with bacteria and kaolinite particles separately to determine their individual transport characteristics in water-saturated columns packed with glass beads. The results indicated that the mass recovery of bacteria and clay particles decreased as the pore water velocity

  2. Evaluating the Onda Mass Transfer Correlation for the Design of Packed-Column Air Stripping

    Microsoft Academic Search

    Jeffery Staudinger; William R. Knocke; Clifford W. Randall

    1990-01-01

    A crucial parameter for predictive modeling of the performance of packed columns is the mass transfer rate. An initial screening identified the Onda mass transfer correlation as the most promising predictive model available. The study described here sought to quantify the accuracy that can be expected with the Onda correlation, based on a test data base that was established using

  3. Evaluation of fructooligosaccharides separation using a fixed-bed column packed with activated charcoal.

    PubMed

    Kuhn, Raquel Cristine; Mazutti, Marcio A; Albertini, Lilian Buoro; Filho, Francisco Maugeri

    2014-05-25

    Recent studies have shown that the chromatographic separation of mixtures of saccharides may be improved by making use of activated charcoal, a promising low cost material for the separation of sugars, including fructooligosaccharides. In this work, the development of a methodology to separate fructooligosaccharides from glucose, fructose and sucrose, using a fixed bed column packed with activated charcoal is proposed. The influence of temperature, eluant concentration and step gradients were evaluated to increase the separation efficiency and fructooligosaccharide purity. The final degree of fructooligosaccharide purification and separation efficiency were about 94% and 3.03 respectively, using ethanol gradient concentration ranging from 3.5% to 15% (v/v) at 40°C. The fixed bed column packed with the activated charcoal was shown to be a promising alternative for sugar separation, mainly those rich in fructooligosaccharides, leading to solutions of acceptable degrees of purification. PMID:24583465

  4. Characteristics of a new HPLC column packed with octadecyl-bonded polymer gel

    Microsoft Academic Search

    Y. Yanagihara; K. Yasukawa; U. Tamura; T. Uchida; K. Noguchi

    1987-01-01

    Summary  The chromatographic efficiency and stability of a new octadecyl-bonded polymer (ODP) gel, developed for reversed phase liquid\\u000a chromatography (RPLC) by substitution of stearate ester groups for the hydroxyl groups of vinyl alcohol copolymer particles,\\u000a were investigated and compared with those of conventional gels. The efficiency of the column packed with the ODP gel was practically\\u000a unaffected by repeated alternating passages

  5. Boron Isotope Fractionation in Liquid Chromatography with Boron-Specific Resins as Column Packing Material

    Microsoft Academic Search

    Takao Oi; Hiromi Shimazaki; Reiko Ishii; Morikazu Hosoe

    1997-01-01

    Boron-specific resins with n-methyl glucamine as the functional group were used as column packing material of liquid chromatography for boron isotope separation. The shapes of chromatograms in reverse breakthrough experiments were heavily dependent on the pH of the eluents, and there existed a pH value at which a chromatogram of the displacement type was realized nearly ideally. The value of

  6. Experimental and Theoretical Studies on the Start-Up Operation of a Multivessel Batch Distillation Column

    E-print Network

    Skogestad, Sigurd

    Experimental and Theoretical Studies on the Start-Up Operation of a Multivessel Batch DistillationVersity of Science and Technology, Trondheim, Norway Multivessel batch distillation is a promising alternative to conventional batch distillation. Earlier studies proved the feasibility of temperature control in a closed

  7. Continuous metal removal from solution and industrial effluents using Spirogyra biomass-packed column reactor.

    PubMed

    Singh, Alpana; Kumar, Dhananjay; Gaur, J P

    2012-03-01

    The granules of Spirogyra neglecta biomass, diameter 0.2-0.5mm, were successfully prepared by boiling it in urea-formaldehyde mixture. Metal sorption performance of the column packed with Spirogyra granules was assessed under variable operating conditions, such as, different influent metal concentrations, bed heights and flow rates. These conditions greatly influenced the breakthrough time and volume, saturation time and volume, and the ability of the column to attain saturation after reaching the breakthrough. The experimental breakthrough curves obtained under varying experimental conditions were modeled using Bohart-Adams, Wolborska, Thomas, Yoon-Nelson and modified dose-response models. The first two models were valid only in representing the initial part of the breakthrough curves; however, the other three models were good in representing the entire breakthrough curve. The granule-packed column could be successfully used up to 6 and 9 cycles of sorption and desorption for the removal of Cu(II) and Pb(II), respectively. The column could efficiently remove different metals from real industrial effluents, and hence the test biomass (Spirogyra granules) is a good candidate for commercial application. PMID:22169159

  8. PRECISION AND ACCURACY IN THE DETERMINATION OF ORGANICS IN WATER BY FUSED SILICA CAPILLARY COLUMN GAS CHROMOTOGRAPHY/MASS SPECTROMETRY AND PACKED COLUMN GAS CHROMATOGRAPHY/MASS SPECTROMETRY

    EPA Science Inventory

    Two general methods for the identification and measurement of organic compounds in water are compared. One method employs packed column chromatography and the other fused silica capillary column chromatography. The two gas chromatography/mass spectrometry (GC/MS) methods use diff...

  9. Simulation of hydrogen sulphide absorption in alkaline solution using a packed column.

    PubMed

    Azizi, Mohamed; Biard, Pierre-François; Couvert, Annabelle; Ben Amor, Mohamed

    2014-01-01

    In this work, a simulation tool was developed for hydrogen sulphide (H?S) removal in an alkaline solution in packed columns working at countercurrent. Modelling takes into account the mass-transfer enhancement due to the reversible reactions between H?S and the alkaline species (CO(²?)(3), HCO?(3), and HO?) in the liquid film. Many parameters can be controlled by the user such as the gas and liquid inlet H?S concentrations, the gas and liquid flow rates, the scrubbing liquid pH, the desired H?S removal efficiency, the temperature, the alkalinity, etc. Since the influence of the hydrodynamic and mass-transfer performances in a packed column is well known, the numerical resolutions performed were dedicated to the study of the influence of the chemical conditions (through the pH and the alkalinity), the temperature and the liquid-to-gas mass flow rate ratio (L/G). A packed column of 3 m equipped with a given random packing material working at countercurrent and steady state has been modelled. The results show that the H?S removal efficiency increases with the L/G, the pH, the alkalinity and more surprisingly with the temperature. Alkalinity has a very significant effect on the removal efficiency through the mass-transfer enhancement and buffering effect, which limits pH decreasing due to H?S absorption. This numerical resolution provides a tool for designers and researchers involved in H?S treatment to understand deeper the process and optimize their processes. PMID:25244138

  10. Effects of reflux ratio and feed conditions for the purification of bioethanol in a continuous distillation column

    NASA Astrophysics Data System (ADS)

    Dasan, Y. K.; Abdullah, M. A.; Bhat, A. H.

    2014-10-01

    Continuous distillation column was used for the purification of bioethanol from fermentation of molasses using Saccharomyces cerevisia. Bioethanol produced was at 8.32% (v/v) level. The efficiency of continuous distillation process was evaluated based on reflux ratio, and feed condition. The lab results were validated using COFE simulation Software. The analyses showed that both reflux ratio and feed condition had significant effects on the distillation process. Stages increased from 1.79 to 2.26 as the reflux ratio was decreased from 90% to 45% and the saturated feed produced lower mole fraction of desired product. We concluded that the lower reflux ratio with cold feed condition was suitable for higher mole fraction of top product.

  11. Packing of large-scale chromatography columns with irregularly shaped glass based resins using a stop-flow method

    PubMed Central

    Siu, Sun Chau; Chia, Celeste; Mok, Yanglin; Pattnaik, Priyabrata

    2014-01-01

    Rigid chromatography resins, such as controlled pore glass based adsorbents, offer the advantage of high permeability and a linear pressure-flow relationship irrespective of column diameter which improves process time and maximizes productivity. However, the rigidity and irregularly shaped nature of these resins often present challenges in achieving consistent and uniform packed beds as formation of bridges between resin particles can hinder bed consolidation. The standard flow-pack method when applied to irregularly shaped particles does not yield well-consolidated packed beds, resulting in formation of a head space and increased band broadening during operation. Vibration packing methods requiring the use of pneumatically driven vibrators are recommended to achieve full packed bed consolidation but limitations in manufacturing facilities and equipment may prevent the implementation of such devices. The stop-flow packing method was developed as an improvement over the flow-pack method to overcome these limitations and to improve bed consolidation without the use of vibrating devices. Transition analysis of large-scale columns packed using the stop-flow method over multiple cycles has shown a two- to three-fold reduction of change in bed integrity values as compared to a flow-packed bed demonstrating an improvement in packed bed stability in terms of the height equivalent to a theoretical plate (HETP) and peak asymmetry (As). PMID:25080096

  12. CO2 absorption in nanofluids in a randomly packed column equipped with magnetic field

    NASA Astrophysics Data System (ADS)

    Salimi, J.; Haghshenasfard, M.; Etemad, S. Gh.

    2014-10-01

    Magnetic nanofluids have been used for absorption of CO2 in a packed column in the presence of magnetic field. Adding nanoparticles into the solvent enhances mass transfer characteristics. The optimum concentrations of Fe3O4/water and NiO/water nanofluids are 0.005, and 0.01 % respectively, and the maximum enhancement of mass transfer rate in comparison with pure water is 12 and 9.5 % respectively. The magnetic field showed positive effect on the CO2 absorption performance.

  13. COED Transactions, Vol. X, No. 5, May 1978. STAGEF, A Program to Compute the Internal Variables of an Operating Distillation Column.

    ERIC Educational Resources Information Center

    Marcovitz, Alan B., Ed.

    A digital computer program, STAGEF, designed for use with the distillation experiments in a typical undergraduate Chemical Engineering laboratory in Unit Operations is explained. The program enables the student to determine the rate of liquid overflow and vapor boil-up which leaves each tray within the distillation column. The student may also…

  14. Packed-column supercritical fluid chromatography/mass spectrometry via a two-stage momentum separator.

    PubMed

    Edlund, P O; Henion, J D

    1989-06-01

    The practical utility of a two-stage momentum separator for combining packed-column supercritical fluid chromatography (SFC) with mass spectrometry (MS) is described. A Hewlett-Packard model 1084B liquid chromatograph modified for packed-column SFC is connected to a linear fused-silica capillary restrictor housed in a heated probe held at 60 degrees at the terminus. A makeup of coaxial helium gas (1.5 L/min) or dissolved solvent (0.2-0.4 mL/min) can be introduced at the point of supercritical fluid expansion. The latter SFC effluent (0.3-2.0 mL/min) is expanded into a heated (44 degrees) desolvation chamber and directed through a nozzle positioned at the entrance of a two-stage momentum separator. Enrichment of the analyte relative to the volatile gases allows the transfer of sample particles to the MS ion source to produce electron ionization of flash-volatilized eluates. On-line SFC/MS separation and detection of low microgram levels of involatile, thermally labile analytes in synthetic mixtures is accomplished. Identification of an unknown compound in a drug tampering incident and the identification of an unknown metabolite isolated from horse urine is also accomplished. PMID:2738147

  15. Effects of Gravity on Cocurrent Two-Phase Gas-Liquid Flows Through Packed Columns

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri; Kamotani, Yasuhiro

    2001-01-01

    This work presents the experimental results of research on the influence of gravity on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid two-phase flow through packed columns. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under reduced gravity conditions compared to normal gravity cocurrent down-flow. This is illustrated by comparing the flow regime transitions found in reduced gravity with the transitions predicted by Talmor. Next, the effect of gravity on the total pressure drop in a packed column is shown to depend on the flow regime. The difference is roughly equivalent to the liquid static head for bubbly flow but begins to decrease at the onset of pulse flow. As the spray flow regime is approached by increasing the gas to liquid ratio, the effect of gravity on pressure drop becomes negligible. Finally, gravity tends to suppress the amplitude of each pressure pulse. An example of this phenomenon is presented.

  16. Report on Qiagen Columns with Precipitation versus Packed Bed Technology for Trace Amounts of DNA

    SciTech Connect

    Wheeler, E K; Erler, A M; Seiler, A

    2008-02-05

    The assured limit of detection (LOD), where 100% of the PCR assays are successful, for the Qiagen spin column is dramatically improved when combined with an ethanol precipitation step of the eluted sample. A detailed SOP for the ethanol precipitation was delivered as a separate report. A key finding in the precipitation work was to incubate the ethanol precipitation at -20{sup o}C overnight when concentrating low copy number samples. Combining this modified ethanol precipitation with the Qiagen spin columns, the limit of assured detection was improved by 1-2 orders of magnitude, for the aliquot and assay variables used. The lower limit of detection (defined as when at least 1 assay of 1 aliquot was positive) was only improved by approximately 1 order of magnitude. The packed bed process has the potential of a 20-fold improvement in the limit of detection compared to Qiagen plus precipitation, based on a mass balance analysis for the entire DNA concentration and purification processes. Figure ES1 shows a mass balance for all the DNA processing steps. The packed bed process minimizes losses from elution, precipitation, and pipetting (aliquoting and transferring). Figure ES1 assumes that 100 copies of DNA serve as the input sample. Efficiencies for each step have been estimated based on our experiences or a worst case scenario (for example, a 50% loss was assumed for pipetting). Table ES1 summarizes the number of copies that are the input template for PCR assuming 100 copies of DNA are processed through the three options detailed in Figure ES1.Theoretically a 20-fold increase in the number of starting copies in the PCR reaction is gained when the DNA is concentrated, purified and then amplified directly on the surface of the beads in the packed bed.

  17. Ultrafast liquid chromatography/tandem mass spectrometry bioanalysis of polar analytes using packed silica columns.

    PubMed

    Shou, Wilson Z; Chen, Yu-Luan; Eerkes, Angela; Tang, Yong Q; Magis, Lisa; Jiang, Xiangyu; Naidong, Weng

    2002-01-01

    Ultrafast liquid chromatography/tandem mass spectrometry (LC/MS/MS) bioanalysis was demonstrated with the use of packed silica columns operated under elevated flow rates. A special effort has been made to achieve ultrafast analysis without sacrificing chromatographic resolution. Two multiple analyte/metabolites assays, (1) morphine/morphine-6-glucuronide(M6G)/morphine-3-glucuronide(M3G) and (2) midazolam/1'-hydroxymidazolam/4-hydroxymidazolam, were used to demonstrate the speed, sensitivity, peak shape and separation of the ultrafast methods utilizing silica columns. In both methods adequate chromatographic separation was a necessity because quantitation results would be otherwise compromised due to cross interference between different selected reaction monitoring (SRM) transitions. Baseline resolutions between morphine, M6G and M3G in human plasma extracts were achieved within 30 s on a 50 x 3 mm Betasil silica column operated at 4 mL/min of isocratic acetonitrile/water mobile phase. The total injection-to-injection cycle time was 48 s with a simple, single-autosampler/single-column setup, when a Shimadzu SIL-HT autosampler was used. Baseline resolution between 1'-hydroxymidazolam and 4-hydroxymidalolam in monkey plasma extracts was achieved within 33 s using similar conditions. Due to the absence of carry-over in this case, no rinsing of the injection needle was necessary, resulting in a cycle time of only 39 s/sample. These ultrafast methods were successfully used to analyze extracted biological samples and proved to be reproducible, reliable and generated equivalent pharmaco-kinetic (PK) results to those obtained by regular flow LC/MS/MS analysis to support discovery PK studies. PMID:12203228

  18. Permeability Change of Crystalline Silicate Mineral-Packed Bed Column by Highly Alkaline Plume

    SciTech Connect

    Hideo Usui; Yuichi Niibori; Hitoshi Mimura [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aramaki Aza Aoba 6-6-01-2, Aoba-ku, Sendai, 980-8579 (Japan); Osamu Tochiyama [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577 (Japan)

    2007-07-01

    For the construction of the geological disposal system, the use of the cementitious material may change the permeability of the natural barrier around the repository. Cementitious materials may alter the pH of ground water to highly alkaline. Also, the potential permeability change of the natural barrier is one of the notable factors for performance assessments of geological disposal systems. In the high pH region, the solubility of silica is very high compared to that in the natural pH (around 8). Therefore, highly alkaline groundwater would dissolve and alter a part of rock surface. Usui et al. (2005) reported that the change of mineral pore structure due to chemical reaction is the key factor to consider the change of the permeability [5-6]. Moreover, such a change of the pore structure was considered to be the result of the spatial heterogeneity of chemical composition. Since such spatial heterogeneity exists also in the sedimentary rocks consisting of crystalline minerals such as quartz and feldspar, we need to examine natural rock, in order to obtain more reliable understanding about the change of permeability induced by highly alkaline groundwater (plume). In this study, silica sand as crystalline mineral was packed in the column, and the effect of dissolution induced by the highly alkaline plume on the permeability-change was examined. The silica sand particles mainly consist of SiO{sub 2} and include Al{sub 2}O{sub 3}, FeO, and K{sub 2}O. The volumetric flow rate and the pressure difference between the inlet and outlet of the column were measured, and the permeability was calculated. At the same time, the concentrations of elements in the fluid were measured by ICP-AES. The experimental result showed that permeability decreased gradually, although the silica sand was continuously dissolved in the column. The behavior of the permeability is considered to be the result from the rearrangement of the particles, or precipitation of secondary mineral. In the column test using the silica sand as packed mineral, the flow-path seems to be clogged by the rearrangement of the particles rather than the increase of the pore space between the particles. (authors)

  19. Synthesis of porous polyaromatic column packings for GC analysis of extraterrestrial atmospheres

    NASA Technical Reports Server (NTRS)

    Woeller, F. H.; Pollock, G. E.

    1978-01-01

    The preparation of a polymer for the Pioneer-Venus Large Probe Gas Chromatograph and another polymer for gas-chromatographic analysis of the Jovian atmosphere is described. Technical-grade divinylbenzene is used as a reliable and economical source of monomer for the preparation of polymer beads. The discussion covers monomeric preparation, polymerization apparatus, first-stage polymer beads, second-stage polymer beads, amino-polymer, columns and gas-chromatographic testing instrumentation used. The polymer for the Pioneer-Venus gas chromatograph is also suitable for ammonia but not for amine analysis. However, the polymer for the analysis of the Jovian atmosphere is a chemically derivatized aromatic polymer that is suitable for amine analysis. The two-stage polymerization produces a highly efficient polymer packing clearly superior to others prepared by adjusted dilution of the aqueous-organic suspension system.

  20. The many faces of packed column supercritical fluid chromatography--a critical review.

    PubMed

    Lesellier, Eric; West, Caroline

    2015-02-20

    Packed column sub- and supercritical fluid chromatography (SFC) is a versatile separation method: on the one hand the number of parameters acting on the quality of a separation is very large, and the effects of these parameters can be complex (and not always fully understood). But on another hand, due to numerous advantageous properties of CO2-based mobile phases, method development is a fast task. This paper is a review of the main features of SFC, focusing essentially on achiral separations. However, several fundamental aspects discussed here are also relevant to chiral SFC separations. This is not intended to be an extensive review, as the way to practice SFC has somewhat evolved with time. We rather wished to provide an expert opinion on the characteristics of the method, pointing at the sources of difficulty and displaying the wide possibilities that it offers. A large number of selected applications concerning several different areas are also presented. PMID:25604272

  1. Modern analytical supercritical fluid chromatography using columns packed with sub-2 ?m particles: a tutorial.

    PubMed

    Nováková, Lucie; Perrenoud, Alexandre Grand-Guillaume; Francois, Isabelle; West, Caroline; Lesellier, Eric; Guillarme, Davy

    2014-05-01

    This tutorial provides an overview of the possibilities, limitations and analytical conditions of modern analytical supercritical fluid chromatography (SFC) using columns packed with sub-2 ?m particles. In particular, it gives a detailed overview of commercially available modern SFC instrumentation and the detectors that can be employed (UV, MS, ELSD, FID, etc.). Some advice on the choice of the stationary phase dimensions and chemistries, the nature of the mobile phase (choice of organic modifier and additives) and its flow rate as well as the backpressure and temperature are also provided. Finally, several groups of potentially problematic compounds, including lipophilic compounds, hydrophilic substances and basic drugs, are discussed in detail. All these families of analytes can be resolved with SFC but require specific analytical conditions. PMID:24759745

  2. Boron isotope fractionation in liquid chromatography with boron-specific resins as column packing material

    SciTech Connect

    Oi, Takao; Shimazaki, Hiromi; Ishii, Reiko [Sophia Univ., Tokyo (Japan); Hosoe, Morikazu [National Defense Academy, Kanagawa (Japan)

    1997-07-01

    Boron-specific resins with n-methyl glucamine as the functional group were used as column packing material of liquid chromatography for boron isotope separation. The shapes of chromatograms in reverse breakthrough experiments were heavily dependent on the pH of the eluents, and there existed a pH value at which a chromatogram of the displacement type was realized nearly ideally. The value of the single-stage separation factor for the boron isotopes varied between 1.010 and 1.022, depending on the temperature and the form of the resins. The existence of the three-coordinate boron species in addition to the four-coordinate species in the resin phase is suggested.

  3. Retardation of chromate through packed columns of surfactant-modified zeolite.

    PubMed

    Li, Zhaohui; Hong, Hanlie

    2009-03-15

    In this study, zeolite aggregates with particle size < 0.4, 1.4-2.4, and 3.6-4.8 mm were modified by the cationic surfactant hexadecyltrimethylammonium (HDTMA) bromide to a surfactant loading level of 80, 130, and 250 mmol kg(-1), respectively. The modified and unmodified zeolites were subjected to column tests to study the chromate transport and retardation as affected by particle size. At an input concentration of 11-15 mg L(-1), unmodified zeolite did not retard chromate transport for all three particle size ranges. In contrast, the observed retardation factor for chromate, defined as the number of pore volumes passed when the output concentration equals to half of the input concentration, was 55, 50, and 500 for the columns packed with 3.6-4.8, 1.4-2.4, and < 0.4 mm modified zeolite, respectively. Prolonged tailing of chromate desorption from the modified zeolite was the most striking feature after the feeding solution was switched from chromate to water at full breakthrough. Monitoring of HDTMA and counterion bromide concentration in the effluent revealed that slow but persistent desorption of HDTMA and bromide occurred throughout the transport experiment, which resulted in stripping off of the upper layer of the surfactant bilayer formation on zeolite. The change of HDTMA surfactant surface configuration from bilayer to monolayer resulted in a loss of functionality to absorb and immobilize chromate on the modified zeolite surfaces. PMID:18656307

  4. Transport of viruses through saturated and unsaturated columns packed with sand

    USGS Publications Warehouse

    Anders, R.; Chrysikopoulos, C.V.

    2009-01-01

    Laboratory-scale virus transport experiments were conducted in columns packed with sand under saturated and unsaturated conditions. The viruses employed were the male-specific RNA coliphage, MS2, and the Salmonella typhimurium phage, PRD1. The mathematical model developed by Sim and Chrysikopoulos (Water Resour Res 36:173-179, 2000) that accounts for processes responsible for removal of viruses during vertical transport in one-dimensional, unsaturated porous media was used to fit the data collected from the laboratory experiments. The liquid to liquid-solid and liquid to air-liquid interface mass transfer rate coefficients were shown to increase for both bacteriophage as saturation levels were reduced. The experimental results indicate that even for unfavorable attachment conditions within a sand column (e.g., phosphate-buffered saline solution; pH = 7.5; ionic strength = 2 mM), saturation levels can affect virus transport through porous media. ?? Springer Science+Business Media B.V. 2008.

  5. 1.1 ?m superficially porous particles for liquid chromatography: part II: column packing and chromatographic performance.

    PubMed

    Blue, Laura E; Jorgenson, James W

    2015-02-01

    The predicted advantages of superficially porous particles over totally porous particles are decreased eddy dispersion, longitudinal diffusion, and resistance to mass transfer contributions to the theoretical plate height. While sub-2 micron superficially porous particles are commercially available, further improvements in performance are predicted by decreasing the particle diameter and decreasing the porous layer thickness. 1.1 ?m superficially porous particles with 187? pores have been synthesized using a layer-by-layer method tuned for production of smaller diameter particles. Following synthesis, these particles were packed into 30 ?m i.d. capillary columns and their chromatographic performance evaluated using electrochemical detection. Based on the initial studies, the column efficiency did not meet theory, but was similar to the commercially available products tested. It is believed that the column packing process plays a critical role in the sub-par column performance. To determine if column efficiency could be predicted by solvent-particle interactions, in-solution optical microscopy and sedimentation velocity of particles in various slurry solvents were investigated and compared to column performance. Aggregating slurry solvents, such as methanol were found to produce columns with increased efficiency. The hmin for a column packed with an acetone slurry and a methanol slurry at 3mg/mL were found to be 6.3 and 3.5, respectively. Increasing the slurry concentration to 25mg/mL further improved the efficiency, producing a column with an hmin of 2.6. These efficiency results were accurately predicted by in-solution optical microscopy. PMID:25578043

  6. COAL GASIFICATION/GAS CLEANUP TEST FACILITY. VOLUME 4. A MATHEMATICAL MODEL OF THE PACKED COLUMN ACID GAS ABSORBER

    EPA Science Inventory

    The report describes a mathematical model for adiabatic operation of a packed-column absorber designed to remove acid gases from coal gasification crude product gas. It also gives results of experiments with a small pilot-scale coal gasification/gas cleaning facility designed to ...

  7. Determination of kinetic parameters in the biosorption of copper(II) on Cladophora sp., in a packed bed column reactor

    Microsoft Academic Search

    Z. Aksu; T. Kutsal

    1998-01-01

    In this study, the biosorption of copper(II) ions to the green alga Cladophora sp. was investigated in a packed bed column reactor as a function of flow rate and inlet copper(II) concentration. These two parameters affected the external mass transfer and adsorption rates directly. Mass transfer coefficients were determined from the Wakao Equation evaluating the breakthrough curves obtained at different

  8. Feasability of neat carbon dioxide packed column comprehensive two dimensional supercritical fluid chromatography.

    PubMed

    Guibal, Pierre; Thiébaut, Didier; Sassiat, Patrick; Vial, Jérôme

    2012-09-14

    The design and implementation of comprehensive two dimensional supercritical fluid chromatography (SFC) using neat carbon dioxide as the mobile phase is described. Two conventional supercritical fluid chromatographs were hyphenated via an on line comprehensive 2D liquid chromatography like interface; it consisted of a two loop switching valve allowing the collection of the first dimension column effluent, the second dimension separation of a fraction being performed during the time allowed for the collection of the subsequent fraction of the first dimension eluent. Both dimension separations were monitored via UV detection; for the second dimension, the main flow was diverted to implement flame ionisation detection for the detection of hydrocarbons and the construction of the corresponding colour plots. Some key parameters related to the interfacing of the two dimensions and the chromatographic conditions used in both dimensions are discussed. In this preliminary report, the feasibility of comprehensive 2D SFC is demonstrated on synthetic mixtures of hydrocarbons and its potential on real sample analysis is illustrated by the separation of coal derived vacuum distillate. PMID:22533910

  9. Evaluation of a subsurface oxygenation technique using colloidal gas aphron injections into packed column reactors

    SciTech Connect

    Wills, R.A.; Coles, P.

    1991-11-01

    Bioremediation may be a remedial technology capable of decontaminating subsurface environments. The objective of this research was to evaluate the use of colloidal gas aphron (CGA) injection, which is the injection of micrometer-size air bubbles in an aqueous surfactant solution, as a subsurface oxygenation technique to create optimal growth conditions for aerobic bacteria. Along with this, the capability of CGAs to act as a soil-washing agent and free organic components from a coal tar-contaminated matrix was examined. Injection of CGAs may be useful for remediation of underground coal gasification (UCG) sites. Because of this, bacteria and solid material from a UCG site located in northeastern Wyoming were used in this research. Colloidal gas aphrons were generated and pumped through packed column reactors (PCRS) containing post-burn core materials. For comparison, PCRs containing sand were also studied. Bacteria from this site were tested for their capability to degrade phenol, a major contaminant at the UCG site, and were also used to bioaugment the PCR systems. In this study we examined: (1) the effect of CGA injection on dissolved oxygen concentrations in the PCR effluents, (2) the effect of CGA, H[sub 2]O[sub 2], and phenol injections on bacterial populations, (3) the stability and transport of CGAs over distance, and (4) CGA injection versus H[sub 2]O[sub 2] injection as an oxygenation technique.

  10. Evaluation of a subsurface oxygenation technique using colloidal gas aphron injections into packed column reactors

    SciTech Connect

    Wills, R.A.; Coles, P.

    1991-11-01

    Bioremediation may be a remedial technology capable of decontaminating subsurface environments. The objective of this research was to evaluate the use of colloidal gas aphron (CGA) injection, which is the injection of micrometer-size air bubbles in an aqueous surfactant solution, as a subsurface oxygenation technique to create optimal growth conditions for aerobic bacteria. Along with this, the capability of CGAs to act as a soil-washing agent and free organic components from a coal tar-contaminated matrix was examined. Injection of CGAs may be useful for remediation of underground coal gasification (UCG) sites. Because of this, bacteria and solid material from a UCG site located in northeastern Wyoming were used in this research. Colloidal gas aphrons were generated and pumped through packed column reactors (PCRS) containing post-burn core materials. For comparison, PCRs containing sand were also studied. Bacteria from this site were tested for their capability to degrade phenol, a major contaminant at the UCG site, and were also used to bioaugment the PCR systems. In this study we examined: (1) the effect of CGA injection on dissolved oxygen concentrations in the PCR effluents, (2) the effect of CGA, H{sub 2}O{sub 2}, and phenol injections on bacterial populations, (3) the stability and transport of CGAs over distance, and (4) CGA injection versus H{sub 2}O{sub 2} injection as an oxygenation technique.

  11. Solution of Multicomponent distillation problems for conventional and complex columns at unsteady state operation

    E-print Network

    Pendon, Gregorio Parrenas

    1966-01-01

    ) = $ (u . ) ? V, (0. -'. j'-N) -1' 0' 1' ' ' ' N ji co j' i=1 The quantities D and U. (0 = j =i N) are fixed quantities. This step J becomes very time consuming when a column with several plates is being considered. In the interest of reducing... are specified for a conventional column with a partial con- 0 denser, Waggoner's defining equations for the 9 multipliers are a. s folio~a: (bi/di) = 1(b, /di) (u. . /d. ) = 6. (u. . /d, ), (O=j=N) ji ico j ji ica' (3- g) In the modified procedure...

  12. Application of the theta method to distillation columns where one or more reactions occur per stage

    E-print Network

    Izarraraz, Alicia

    1979-01-01

    to the Problem by the 2N-Newtor Raphson Method 71 N-Newton Rapshon Solution for Column. at Total Reflux without Reaction 72 Calculational Procedure for Solution of Columns at Total Reflux by Theta Method. 73 Calculational Procedure for the 2N-Newton Raph or... the inadequacies of the various methods and concluded that no single technique is applicable to all of these problems. Following the analysis of Friday and Smith, Tierney and Bruno (1967) developed a Newton-Raphson procedure using only material balance...

  13. Demulsification of water-in-oil emulsion by wetting coalescence materials in stirred- and packed-columns

    Microsoft Academic Search

    Sun Dezhi; Jong Shik Chung; Duan Xiaodong; Zhou Ding

    1999-01-01

    Demulsification of emulsified water-in-oil droplets was developed using wetting coalescence materials. Demulsification tests were carried out using conventional stirred- and packed-columns. Of the four kinds of natural fibers and two kinds of inorganic materials tested, natural fiber A, selected from shaves of a wood showed the best performance in demulsification. The demulsification efficiency can exceed 97% when demulsification conditions are

  14. Removal of pollutant compounds from water supplies using ozone, ultraviolet light, and a counter, current packed column. Master's thesis

    SciTech Connect

    Kelly, E.L.

    1991-01-01

    Many water pollutants are determined to be carcinogenic and often appear in very low concentrations and still pose a health risk. Conventional water treatment processes cannot remove these contaminants and there is a great demand for the development of alternative removal technologies. The use of ozone and ultraviolet light in a counter current packed column could prove to be an effective treatment process to remove these contaminants.

  15. Packed-bed sorption of copper using spent animal bones: factorial experimental design, desorption and column regeneration

    Microsoft Academic Search

    Sameer Al-Asheh; Nabil Abdel-Jabar; Fawzi Banat

    2002-01-01

    A two-level factorial experimental design method has been proposed to investigate the influence of the operating parameters in a packed-bed adsorption column. This technique has been applied to quantify the influence of bed-depth, influent flow rate, and influent metal concentration on break-through time during the removal of copper from aqueous solutions using spent animal bones. A factorial model has been

  16. Two-Phase Flow in Packed Columns and Generation of Bubbly Suspensions for Chemical Processing in Space

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Green, R. D.; Nahra, H. K.; Sridhar, K. R.

    2000-01-01

    For long-duration space missions, the life support and In-Situ Resource Utilization (ISRU) systems necessary to lower the mass and volume of consumables carried from Earth will require more sophisticated chemical processing technologies involving gas-liquid two-phase flows. This paper discusses some preliminary two-phase flow work in packed columns and generation of bubbly suspensions, two types of flow systems that can exist in a number of chemical processing devices. The experimental hardware for a co-current flow, packed column operated in two ground-based low gravity facilities (two-second drop tower and KC- 135 low-gravity aircraft) is described. The preliminary results of this experimental work are discussed. The flow regimes observed and the conditions under which these flow regimes occur are compared with the available co-current packed column experimental work performed in normal gravity. For bubbly suspensions, the experimental hardware for generation of uniformly sized bubbles in Couette flow in microgravity conditions is described. Experimental work was performed on a number of bubbler designs, and the capillary bubble tube was found to produce the most consistent size bubbles. Low air flow rates and low Couette flow produce consistent 2-3 mm bubbles, the size of interest for the "Behavior of Rapidly Sheared Bubbly Suspension" flight experiment. Finally the mass transfer implications of these two-phase flows is qualitatively discussed.

  17. Catalytic distillation structure

    DOEpatents

    Smith, Jr., Lawrence A. (Bellaire, TX)

    1984-01-01

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

  18. Calculational procedure for multicomponent distillation columns with side-stream-strippers

    E-print Network

    Dickey, Billy Ray

    1962-01-01

    ( d (yg) ) (B (x ) h ) j+1- (aw) where c-1 B (x ) e~ & x, 2=j=g 1 * j j+1 Q j+l, i ji ia2 (&3b) 9 j+1 y J&lpi Di & 2= j= g 1 &or the side stripper, the corresponding equations are as follovs I V H e~ H' (1 + V? H ) 0~ j+1 j+1 + jel?i ji Ntl 1... substitution of this x ression i: to "n ento il y !;~1 nce st(oh i iclule. +he to, . o!' t 'e ~istill, . t'on column nd ny '1 te j (' -'I(y &. ) 7 ('I(-. ' -H ) J+1 x ' ~ j+1 1 C F-I= j=~ (4ga) j j+1 j where' . I(y ). j+1 c-( I C i=2 (49h) In a sx...

  19. MULTIVESSEL BATCH DISTILLATION EXPERIMENTAL VERIFICATION

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION ­ EXPERIMENTAL VERIFICATION Bernd Wittgens and Sigurd Skogestad 1 The experimental verification of the operation of a multivessel batch distillation column, operated under total vessels, provides a generalization of previously proposed batch distillation schemes. We propose a simple

  20. Biosorption of lead(II) and cadmium(II) by protonated Sargassum glaucescens biomass in a continuous packed bed column.

    PubMed

    Naddafi, Kazem; Nabizadeh, Ramin; Saeedi, Reza; Mahvi, Amir Hossein; Vaezi, Forough; Yaghmaeian, Kamyar; Ghasri, Azar; Nazmara, Shahrokh

    2007-08-25

    Biosorption of lead(II) and cadmium(II) from aqueous solutions by protonated Sargassum glaucescens biomass was studied in a continuous packed bed column. The selective uptake of Pb2+ and Cd2+ was investigated in a binary system with initial concentration of 1 mM for each metal ion. The selective uptake capacities of Pb2+ and Cd2+ at complete exhaustion point were obtained 1.18 and 0.22 mmol/g, respectively; therefore, the biosorbent showed much higher relative affinity for Pb2+ than for Cd2+. The optimum range of empty bed contact time (EBCT) was identified as 5-10 min in the packed bed column. The efficiency of biosorbent regeneration by 0.1 M HCl was achieved about 60%, so that the maximum uptake capacity of Pb2+ by the regenerated biomass was determined to be 0.75 mmol/g while the same value for the original biomass was 1.24 mmol/g. The Thomas model was found in a suitable fitness with the experimental data (R2 > 0.90 and % < 50%) at all different operation stages. Monitoring of pH in the effluent of the column presented the simultaneous release of H+ with the uptake of heavy metals; hence, ion exchange was confirmed to be one of the main biosorption mechanisms. PMID:17879424

  1. Dynamics of reactive chromatographic columns of inert core/hollow/film coated spherical packing: an analytical solution and applications.

    PubMed

    Shams, K; Fayazbakhsh, A

    2014-11-28

    The transient behavior of reactive-diffusive fixed-bed (chromatographic columns or reactors) packed with inert core/shell core/hollow/thin film coated monodisperse spherical rigid particles is investigated. We modeled the reactive sorption system with linear mass exchange law between the flowing and the stationary phases. The coupled governing partial differential equations were integrated analytically using Laplace transformations. The analytical closed form solution involves two infinite integrals. The closed form solution was integrated numerically and the breakthrough curves of the system were studied under the influence of the system parameters. The limiting cases are discussed, a simple asymptotic closed form solution for fixed-bed desorbers with monodisperse spherical particles is obtained, and results are generalized for similar kinetics of reactive chromatographic columns (fixed-beds) for diffusion/absorption into the inert core spherical packing. Further, potential applications of the mathematical model and results in processes such as liquid vapor extraction, various forms of chromatography, reactive sorption, multifunctional reactors, process intensification, and regeneration of ion exchange columns are briefly discussed. PMID:25454133

  2. Multivessel Batch Distillation Potential Energy Savings

    E-print Network

    Skogestad, Sigurd

    Multivessel Batch Distillation ­ Potential Energy Savings Bernd Wittgens and Sigurd Skogestad 1, Norway ABSTRACT ­ A conventional batch distillation column operated under feedback control applying the proposed policy is compared to the multivessel batch distillation column. In some cases we found

  3. System dynamics and controller development for denitrification using a packed column bioreactor

    E-print Network

    Boyd, Michael Edward

    1996-01-01

    is biological denitrification. For this study, two 1.5 m x 0.3 m columns were built and placed in parallel. The columns were filled with lava rock to provide sites for denitrifying bacteria to attach themselves. The system was inoculated with water from a golf...

  4. Transport and transformation of sulfadiazine in soil columns packed with a silty loam and a loamy sand.

    PubMed

    Unold, M; Kasteel, R; Groeneweg, J; Vereecken, H

    2009-01-01

    Concerning the transport of the veterinary antibiotic sulfadiazine (SDZ) little is known about its possible degradation during transport. Also its sorption behaviour is not yet completely understood. We investigated the transport of SDZ in soil columns with a special emphasis on the detection of transformation products in the outflow of the soil columns and on modelling of the concentration distribution in the soil columns afterwards. We used disturbed soil columns near saturation, packed with a loamy sand and a silty loam. SDZ was applied as a 0.57 mg L(-1) solution at a constant flow rate of 0.25 cm h(-1) for 68 h. Breakthrough curves (BTC) of SDZ and its transformation products 4-(2-iminopyrimidin-1(2H)-yl)aniline and 4-hydroxy-SDZ were measured for both soils. For the silty loam we additionally measured a BTC for an unknown transformation product which we only detected in the outflow samples of this soil. After the leaching experiments the (14)C-concentration was quantified in different layers of the soil columns. The transformation rates were low with mean SDZ mass fractions in the outflow samples of 95% for the loamy sand compared to 97% for the silty loam. The formation of 4-(2-iminopyrimidin-1(2H)-yl)aniline appears to be light dependent and did probably not occur in the soils, but afterwards. In the soil columns most of the (14)C was found near the soil surface. The BTCs in both soils were described well by a model with one reversible (kinetic) and one irreversible sorption site. Sorption kinetics played a more prominent role than sorption capacity. The prediction of the (14)C -concentration profiles was improved by applying two empirical models other than first order to predict irreversible sorption, but also these models were not able to describe the (14)C concentration profiles correctly. Irreversible sorption of sulfadiazine still is not well understood. PMID:18951658

  5. Transport and transformation of sulfadiazine in soil columns packed with a silty loam and a loamy sand

    NASA Astrophysics Data System (ADS)

    Unold, M.; Kasteel, R.; Groeneweg, J.; Vereecken, H.

    2009-01-01

    Concerning the transport of the veterinary antibiotic sulfadiazine (SDZ) little is known about its possible degradation during transport. Also its sorption behaviour is not yet completely understood. We investigated the transport of SDZ in soil columns with a special emphasis on the detection of transformation products in the outflow of the soil columns and on modelling of the concentration distribution in the soil columns afterwards. We used disturbed soil columns near saturation, packed with a loamy sand and a silty loam. SDZ was applied as a 0.57 mg L - 1 solution at a constant flow rate of 0.25 cm h - 1 for 68 h. Breakthrough curves (BTC) of SDZ and its transformation products 4-(2-iminopyrimidin-1(2 H)-yl)aniline and 4-hydroxy-SDZ were measured for both soils. For the silty loam we additionally measured a BTC for an unknown transformation product which we only detected in the outflow samples of this soil. After the leaching experiments the 14C-concentration was quantified in different layers of the soil columns. The transformation rates were low with mean SDZ mass fractions in the outflow samples of 95% for the loamy sand compared to 97% for the silty loam. The formation of 4-(2-iminopyrimidin-1(2 H)-yl)aniline appears to be light dependent and did probably not occur in the soils, but afterwards. In the soil columns most of the 14C was found near the soil surface. The BTCs in both soils were described well by a model with one reversible (kinetic) and one irreversible sorption site. Sorption kinetics played a more prominent role than sorption capacity. The prediction of the 14C -concentration profiles was improved by applying two empirical models other than first order to predict irreversible sorption, but also these models were not able to describe the 14C concentration profiles correctly. Irreversible sorption of sulfadiazine still is not well understood.

  6. Stability and performance of silica-based alkyl bonded-phase HPLC column packings with pH > 8 mobile phases

    SciTech Connect

    Kirkland, J.J. [Rockland Technologies, Inc., Newport, DE (United States)

    1995-12-01

    Certain HPLC separations are best performed with high pH (pH >8) mobile phases where basic compounds may not be fully protonated. However, the traditional recommendation for silica-based HPLC column packings is that they not be used with mobile phases above pH 8 because of rapid packed-bed degradation by solubility of the silica support. Studies now have shown that packings with certain types of silica supports and bonded phases can be employed successfully for routine separations with mobile phases of at least pH 9. Column packing lifetime with higher pH mobile phases also can be extended by proper choice of buffer type. Silica support solubility (and ultimate column life) is significantly influenced by the nature of both the anions and cations used in the mobile phase buffer. Even at pH 7, some alkyl bonded phase packings show poor lifetime with higher concentrations of certain buffers, especially at elevated temperatures. Column temperature and buffer concentration also greatly affect silica support solubility and ultimate column lifetime. Findings from this study should assist in the development of more rugged HPLC methods for routine applications.

  7. Transverse bacterial migration induced by chemotaxis in a packed column with structured physical heterogeneity

    PubMed Central

    Wang, Meng; Ford, Roseanne M.

    2009-01-01

    The significance of chemotaxis in directing bacterial migration towards contaminants in natural porous media was investigated under groundwater flow conditions. A laboratory-scale column, with a coarse-grained sand core surrounded by a fine-grained annulus, was used to simulate natural aquifers with strata of different hydraulic conductivities. A chemoattractant source was placed along the central axis of the column to model contaminants trapped in the heterogeneous subsurface. Chemotactic bacterial strains, Escherichia coli HCB1 and Pseudomonas putida F1, introduced into the column by a pulse injection, were found to alter their transport behaviors under the influence of the attractant chemical emanating from the central source. For E. coli HCB1, approximately 18% more of the total population relative to the control without attractant exited the column from the coarse sand layer due to the chemotactic effects of ?-methylaspartate under an average fluid velocity of 5.1 m/d. Although P. putida F1 demonstrated no observable changes in migration pathways with the model contaminant acetate under the same flow rate, when the flow rate was reduced to 1.9 m/d, approximately 6~10% of the population relative to the control migrated from the fine sand layer towards attractant into the coarse sand layer. Microbial transport properties were further quantified by a mathematical model to examine the significance of bacterial motility and chemotaxis under different hydrodynamic conditions, which suggested important considerations for strain selection and practical operation of bioremediation schemes. PMID:19731698

  8. Extraction of squalene from shark liver oil in a packed column using supercritical carbon dioxide

    SciTech Connect

    Catchpole, O.J.; Kamp, J.C. von; Grey, J.B. [Industrial Research Limited, Lower Hutt (New Zealand)] [Industrial Research Limited, Lower Hutt (New Zealand)

    1997-10-01

    Continuous extraction of squalene from shark liver oil using supercritical carbon dioxide was carried out in both laboratory and pilot scale plant. The shark liver oil contained around 50% by weight squalene, which was recovered as the main extract stream. The other major components in the oil were triglycerides, which were recovered as raffinate, and pristane, which was recovered as a second extract stream. Separation performance was determined as a function of temperature; pressure; oil to carbon dioxide flow rate ratio, packed height and type of packing; and reflux ratio. The pressure, temperature, and feed oil concentration of squalene determined the maximum loading of oil in carbon dioxide. The oil to carbon dioxide ratio determined the squalene concentration in both the product stream and raffinate stream. The ratio of oil flow rate to the flow rate of squalene required to just saturate carbon dioxide was found to be a useful correlating parameter for the oil loadings and product compositions. Of the three packings investigated, wire wool gave the best separation efficiency and Raschig rings the worst efficiency. Mass transfer correlations from the literature were used to estimate the number of transfer units (NTU) from experimental data and literature correlations. NTU`s from the experimental data were comparable to predictions at a pilot scale but were underpredicted at the laboratory scale. The use of reflux at the pilot scale enabled the concentration of squalene in the product stream to be increased from 92% by mass to a maximum of 99% by mass at fractionation conditions of 250 bar and 333 K.

  9. Description and comparison of chromatographic tests and chemometric methods for packed column classification.

    PubMed

    Lesellier, E; West, C

    2007-07-27

    The main tests developed in last 20 years to investigate the chromatographic behaviour and the stationary phase properties are described in this paper. These properties are the hydrophobicity, depending on the surface area and the bonding density, the number of accessible residual silanol groups having sometimes different acidity, which can interact with neutral solutes by hydrogen bonds or with the ionic form of basic compounds and the shape or steric selectivity, depending on both the functionality of the silanising agent and the bonding density. Two types of tests are performed, either based on key solutes having well defined properties such as phenol, caffeine, amitriptyline, benzylamine, acenaphtene, o-terphenyl, triphenylene, p-ethylaniline, carotenoid pigments, or on retention models (solvation parameter, hydrophobic subtraction) obtained from the analyses of numerous and varied compounds. Thus, the chromatographic properties are either related to selectivities or retention factors calculated from key solutes, or they are described by interaction coefficients provided by multilinear regression from retention models. Three types of comparison methods are used based on these data. First, simple plots allow the study of differences between the columns as regards to one or two properties. Columns located in the same area of the plot display close properties. Second, chemometric methods such as principal component analysis (PCA) or hierarchical cluster analysis (HCA) can be performed to compare columns. In this case, all the studied properties are included in the comparison, done either by data projection to reduce the space in which the information is located (PCA) or by distance calculation and comparison for drawing a classification (HCA). Neighbouring columns are expected to provide identical chromatographic performances. These two chemometric methods can be used together, PCA before HCA. The third way is to calculate a discrimination factor from a reference column, through calculation methods based on the Pythagorean Theorem: the lower this factor, the closer the column properties. Following the presentation of the analytical conditions, the compounds and the data treatments used by the teams working in this field, the pertinence of the different selectivities, i.e. of the different probe solute couples or of the different interaction coefficients, are discussed as regards their discrimination capacity. The accuracy of chemometric treatments in the discrimination of stationary phases having different functionalities (octadecylsiloxane (ODS), cyano, fluorinated, phenyl, polar embedded group or "aqua" type) will be discussed, as well as their performances in the finer ODS discrimination. New two-dimensional plots, from data gained by different studies will be suggested, to improve the classification of stationary phases having different nature of bonded chains. PMID:17467721

  10. Performance of tapered-column packed-bed bioreactor used for ethanol production by immobilized yeast cells

    SciTech Connect

    Hamamci, H.

    1986-01-01

    The tapered-column packed-bed bioreactor was tested as a solution to the problems of pressure drop and nonuniform flow in immobilized-yeast fermentations. The column operation was simulated using a mathematical model considering the effects of the heterogeneous kinetics, interfacial mass transfer, convective and dispersive flows of the liquid phase. The kinetics of ethanol production by the immobilized Saccharomyces cerevisiae was determined using shake-flask batch cultures. It was found that there is a shift in the metabolism of the yeast used at glucose concentrations of about 2 to 5 g/l, and due to this effect two sets of V/sub m/ and K/sub m/ values are determined. Maximum rate of fermentation was found to be 0.80 and 0.39 g ethanol/g cell/hr, and the affinity constant was found to be 97 and 11 mM in the medium and low glucose concentration regions respectively. The rate of fermentation went through a maximum at about 70 g glucose/l and the substrate inhibition constant was found to be 0.76 M. The product inhibition constant was also tested and was found to be 113 g ethanol/l. The column performance was simulated effectively at low residence times and low ethanol concentrations, however at the larger residence times and product concentrations better agreement was obtained by changing the ethanol inhibition constant to 85 g/l. In another set of experiments the effect of inert gas flow and oxygen gas feed into the tapered-column was tested. Inert gas feed helps increase the conversion only at very small flow rates. The effect of oxygen was positive at all the flow rates tested.

  11. Transport and retention of high concentrated nano-Fe/Cu particles through highly flow-rated packed sand column.

    PubMed

    Hosseini, Seiyed Mossa; Tosco, Tiziana

    2013-01-01

    The design of an efficient field-scale remediation based on the use of nanoscale zero valent iron (NZVI) requires an accurate assessment of the mobility of such particles in saturated porous media, both during injection in the subsurface (short-term mobility) and later (long-term mobility). In this study, the mobility of highly concentrated dispersions of bimetallic Fe/Cu nanoparticles (d(50) = 70 ± 5 nm) in sand-packed columns (0.5 m length and 0.025 m inner diameter) was studied. In particular, the influence of flow rate (V = 5 × 10(-4), 1 × 10(-3), 2 × 10(-3) m/s) and injected particle concentrations (2, 5, 8, 12 g/l) was addressed. Breakthrough curves and water pressure drop along the column, averaged effective porosity and final distribution of retained particles along the column were measured. Experimental results evidenced a good mobility of the Fe/Cu particles, with significant breakthrough in all explored experimental conditions of flow rate and C(0), without requiring the addition of any stabilizing agent. Clogging phenomenon of the column and also the pore pressure variation during injection period are strongly affected by injected concentration. Clogging due to deposition of particles following a ripening dynamics was observed in particular for C(0) = 8 and 12 g/l. The experimental data were modeled using the E-MNM1D software. The study has implications for field injection of bimetallic nanoparticles, suggesting that particular care is to be devoted when selecting injection concentration, to avoid porous medium clogging and control the radius of influence. PMID:23141767

  12. Calculation procedure to determine average mass transfer coefficients in packed columns from experimental data for ammonia water absorption refrigeration systems

    NASA Astrophysics Data System (ADS)

    Sieres, Jaime; Fernández-Seara, José

    2008-08-01

    The ammonia purification process is critical in ammonia water absorption refrigeration systems. In this paper, a detailed and a simplified analytical model are presented to characterize the performance of the ammonia rectification process in packed columns. The detailed model is based on mass and energy balances and simultaneous heat and mass transfer equations. The simplified model is derived and compared with the detailed model. The range of applicability of the simplified model is determined. A calculation procedure based on the simplified model is developed to determine the volumetric mass transfer coefficients in the vapour phase from experimental data. Finally, the proposed model and other simple calculation methods found in the general literature are compared.

  13. Comparison of Packed Beds and Qiagen Columns for Recovering Trace Amounts of B. anthracis DNA from Liquid Suspensions

    SciTech Connect

    Sorensen, K; Arroyo, E; Erler, A; Christian, A T; Camp, D; Wheeler, E K

    2006-06-23

    The goal of this work was to optimize and evaluate LLNL's in-bed amplification technology to improve the level of detection for suspensions containing trace amounts of anthracis DNA. The binding/cleaning performance of the packed bed is compared to the conventional commercial approach; Qiagen column cleanup and elution, followed by detection through an ex-situ amplification process. Five liquid suspensions were spiked with B.anthracis DNA in concentration series. These suspensions were: (1) water, (2) water with EDTA, (3) dirty water from carpet extraction, (4) dirty carpet extraction with phosphate buffered saline (PBS) plus 0.1% Tween 20 plus 0.1% gelatin, and (5) a subway aerosol collected in water. Each suspension matrix was spiked with DNA and injected (in replicate) into either Qiagen Microcolumns (using the kit processing instructions) or LLNL's packed bed (using the LLNL in-bed purification and amplification protocol). The process output was assayed by quantitative polymerase chain reaction (QPCR). Table ES-1 shows the level of DNA (pg per 100 uL of input suspension) that resulted in successful amplification for all reactions (X=Y), and the level for which at least one of the reactions was successful (X>0). For each suspension and DNA concentration, there were Y QPCR assays of which X showed successful amplification. LLNL's packed bed technology outperformed Qiagen Microcolumns for all five suspensions, typically by one order of magnitude in both the limit of assured detection (all reactions positive), and the lower limit of detection (some reactions positive).

  14. Flow counterbalanced capillary electrophoresis using packed capillary columns: resolution of enantiomers and isotopomers.

    PubMed

    Henley, W Hampton; Wilburn, Richard T; Crouch, Andrew M; Jorgenson, James W

    2005-11-01

    A method with the ability to increase greatly both the resolution and efficiency of a given capillary electrophoretic system is described. This method differs from traditional capillary electrophoresis (CE) in that a counterflow is induced in the direction opposite to the electrokinetic migration of the analyte. This has the effect of extending not only the time the analytes migrate in the electric field but also the effective length and the effective applied voltage of the system. Previous work in our group with flow counterbalanced capillary electrophoresis has utilized an open tube of small inner diameter to reduce peak broadening caused by hydrodynamic flow. Narrow-diameter capillaries (5-10 microm) restricted analysis to fluorescent analytes and laser-induced fluorescence detection. The method described here uses a capillary of much larger inner diameter (75 microm) that has been packed with nonporous silica particles. The packing material reduces the amount of band broadening caused by pressure-induced flow relative to that experienced in an open tube. A larger diameter capillary allows the detection of analytes by UV absorption, not only eliminating the need to tag analytes with fluorescent tags but also allowing for the detection of a much broader range of analytes. The system was evaluated by studying the separations of several enantiomers using only beta-cyclodextrin as the chiral selector. The system was also used to resolve the two naturally occurring isotopes of bromine and to resolve phenylalanine from phenylalanine-d8. Relative to traditional CE, large improvements in resolution and separation efficiency have been achieved with this method. PMID:16255605

  15. Adsorption performance of packed bed column for nitrate removal using PAN-oxime-nano Fe2O3

    PubMed Central

    2014-01-01

    A continuous fixed bed study was carried out by using PAN-oxime-nano Fe2O3 as a sorbent for the removal of nitrate from aqueous solution. The effect of factors, such as flow rate (2, 5 and 7 mL/min) and bed depth (5, 10 and 15 cm) were studied. Data confirmed that the breakthrough curves were dependent on flow rate and bed depth. The adsoption capacities observed in diffent conditions of flow rates (2,5 and 7 mL/min) were 11.65, 24.38 and 25.89, respectively. Thomas model was applied to experimental data to predict the breakthrough curves using linear regression and to determine the characteristic parameters of the packed bed column. Bed depth/service time analysis (BDST) model was used to investigate the effect of bed depth on breakthrough curves. The results showed that Thomas model was suitable for the normal description of breakthrough curve at the experimental condition. The data were in good agreement with BDST model with R2?>?0.98. Statistical analyses were performed on fluoride removal obtained from different flow rates using SPSS16 software by applying Kruskal- Wallis test. These findings suggested that PAN-oxime-nano Fe2O3 in the column structure presents a great potential in removal of nitrate from aqueous solutions. PMID:25045525

  16. Transport models for desorption from natural soils packed in flushed columns

    NASA Astrophysics Data System (ADS)

    Brouwers, H. J. H.

    1999-06-01

    This paper addresses an experimental and theoretical study of sorbed contaminant removal from a column (or reactor) by flushing. This removal may take place by either volatilization or rinsing, and nonlinear sorption is accounted for by employing a Freundlich relationship. A one-dimensional nonequilibrium transport model is proposed which describes the unsteady mass transfer between flushing medium and soil phases in the column, using a linear chemical transfer model. The moving boundary problem is transferred, and a perturbation method is employed to obtain an approximate solution of the governing equations for a small Merkel number Me (this dimensionless number comprises the product of fluid residence time and the mass transfer coefficient). The solution reveals the effect of the various parameters, such as the Freundlich parameter n, on the contaminant transport in fluid phase and decay in solid phase. Applying the model to various experimental data results in values for the overall mass transfer coefficients, which are useful for engineering computations. Furthermore, the model enables the prediction of the initial soil contamination level as well as the parameter n solely from the measured exit contaminant concentrations in the flushing fluid. A thorough comparison of this prediction with the measured soil concentration (prior to the experiments) yields good agreement.

  17. Evaluation by respirometry of the degradability of retort water using a shale ash and overburden packed column.

    PubMed

    Clarke, W P; Ho, N M; Taylor, M; Coombs, S; Bell, P R; Picaro, T

    2005-08-01

    Oil shale processing produces an aqueous wastewater stream known as retort water. The fate of the organic content of retort water from the Stuart oil shale project (Gladstone, Queensland) is examined in a proposed packed bed treatment system consisting of a 1:1 mixture of residual shale from the retorting process and mining overburden. The retort water had a neutral pH and an average unfiltered TOC of 2,900 mg 1(-1). The inorganic composition of the retort water was dominated by NH4+. Only 40% of the total organic carbon (TOC) in the retort water was identifiable, and this was dominated by carboxylic acids. In addition to monitoring influent and effluent TOC concentrations, CO2 evolution was monitored on line by continuous measurements of headspace concentrations and air flow rates. The column was run for 64 days before it blocked and was dismantled for analysis. Over 98% of the TOC was removed from the retort water. Respirometry measurements were confounded by CO2 production from inorganic sources. Based on predictions with the chemical equilibrium package PHREEQE, approximately 15% of the total CO2 production arose from the reaction of NH4+ with carbonates. The balance of the CO2 production accounted for at least 80% of the carbon removed from the retort water. Direct measurements of solid organic carbon showed that approximately 20% of the influent carbon was held-up in the top 20cm of the column. Less than 20% of this held-up carbon was present as either biomass or as adsorbed species. Therefore, the column was ultimately blocked by either extracellular polymeric substances or by a sludge that had precipitated out of the retort water. PMID:16128388

  18. Repeatability of the efficiency of columns packed with sub-3?m core-shell particles: Part I. 2.6?m Kinetex-C(18) particles in 4.6mm and 2.1mm×100mm column formats.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2012-08-24

    The column-to-column repeatability of the mass transfer mechanism in columns packed with sub-3?m shell particles was investigated. The parameters of this mechanism were measured for twelve columns (six 2.1mm×100mm and six 4.6mm×100mm) packed with the same batch of 2.6?m Kinetex-C(18) particles (Phenomenex, CA, USA). For both series, the manufacturer provided columns at different positions in the efficiency distribution given by the quality test control. Three compounds were used, uracil, naphthalene and insulin. The reduced longitudinal diffusion term was measured with the peak parking (PP) method, the reduced solid-liquid mass transfer resistance term was given by a combination of the PP results and a model of effective diffusion in ternary composite materials (non-porous cores, concentric porous shell, and eluent matrix), validated previously. The overall eddy diffusion term was obtained by subtraction of these two HETP terms from the overall reduced HETP measured by numerical integration of the entire peak profiles. The results demonstrate that the dispersion of the column efficiencies is only due to the random nature of the packing process. At the highest reduced velocity achieved, the relative standard deviations (RSDs) of the eddy diffusion term for the 2.1mm I.D. columns were ca. 7% and 3% for the low molecular weight compounds and for insulin, respectively. For the 4.6mm I.D. columns, these RSDs were 15% and 5%, respectively. The larger RSDs for the 4.6mm I.D. columns is explained by the exceptionally low value of the eddy diffusion term. PMID:22762953

  19. Continuous adsorption of natural organic matters in a column packed with carbon nanotubes

    PubMed Central

    2013-01-01

    In the present study, continuous adsorption experiments were carried out in an adsorption column to survey the efficiency of the carbon nanotubes (CNTs) for removal of natural organic matters (NOMs) from aqueous solution. Parameters such as mass of CNTs, initial NOMs concentration were evaluated and also the breakthrough curves were obtained. Experiments performed with various initial NOMs concentration and various CNTs masses. The breakthrough period was longer at lower initial NOMs concentration. Increase of the initial NOMs concentration, expectedly, resulted in the faster saturation of the CNTs bed. The adsorption capacities for multi wall carbon nanotubes (MWCNT) and single wall carbon nanotubes (SWCNT) in highest initial NOMs concentration were 53.46 and 66.24 mg/g, respectively. The effect of amount of CNTs on breakthrough time and volume of treated water was investigated and resulted that with an increase in the mass of CNTs, breakthrough time occurs very late and the volume of treated water increased. These findings suggested that CNTs present a great potential in removal of NOMs from aqueous solutions. PMID:24499604

  20. Rigorous Synthesis and Simulation of Complex Distillation Networks

    E-print Network

    Linninger, Andreas A.

    Rigorous Synthesis and Simulation of Complex Distillation Networks Gerardo J. Ruiz, Seon B. Kim energy-efficient distillation net- works. Complex column networks have substantial potential for energy column, networks, temperature collocation, inverse design, Aspen validation Introduction Distillation

  1. Quantitative Analysis of Transverse Bacterial Migration Induced by Chemotaxis in a Packed Column with Structured Physical Heterogeneity

    PubMed Central

    Wang, Meng; Ford, Roseanne M.

    2009-01-01

    A two-dimensional mathematical model was developed to simulate transport phenomena of chemotactic bacteria in a sand-packed column designed with structured physical heterogeneity in the presence of a localized chemical source. In contrast to mathematical models in previous research work, in which bacteria were typically treated as immobile colloids, this model incorporated a convective-like chemotaxis term to represent chemotactic migration. Consistency between experimental observation and model prediction supported the assertions that (1) dispersion-induced microbial transfer between adjacent conductive zones occurred at the interface and had little influence on bacterial transport in the bulk flow of the permeable layers and (2) the enhanced transverse bacterial migration in chemotactic experiments relative to nonchemotactic controls was mainly due to directed migration toward the chemical source zone. Based on parameter sensitivity analysis, the results showed that chemotactic parameters determined in bulk aqueous fluid were adequate to predict the microbial transport in our intermediate-scale porous media system. Additionally, the analysis of adsorption coefficient values supported the observation of a previous study that microbial deposition to the surface of porous media might be decreased under the effect of chemoattractant gradients. By quantitatively describing bacterial transport and distribution in a heterogeneous system, this mathematical model serves to advance our understanding of chemotaxis and motility effects in granular media systems and provides insights for modeling microbial transport in in situ microbial processes. PMID:20000726

  2. Biosurfactant-producing and oil-degrading Bacillus subtilis strains enhance oil recovery in laboratory sand-pack columns.

    PubMed

    Gudiña, Eduardo J; Pereira, Jorge F B; Costa, Rita; Coutinho, João A P; Teixeira, José A; Rodrigues, Lígia R

    2013-10-15

    Microbial Enhanced Oil Recovery (MEOR) technology uses microorganisms and their metabolites to retrieve unrecoverable oil from mature reservoirs. In situ stimulation of biosurfactant-producing and oil-degrading microorganisms reduces the capillary forces retaining the oil inside the reservoir and decreases its viscosity, thus promoting oil flow and consequently production. In this work, a sand-pack column model was designed to simulate oil recovery operations and evaluate mobilization of residual oil by the selected microorganisms. Four different hydrocarbon mixtures and three Bacillus subtilis strains isolated from crude oil samples were used. Additional oil recoveries ranged from 6 to 24% depending on the hydrocarbon mixture and microorganism used. Biosurfactant production was observed with all the microorganisms and hydrocarbon mixtures studied. The oils recovered after incubation with B. subtilis isolates showed a reduction in the percentage of long-chain n-alkanes and lower viscosity when compared with the original oils. The results obtained suggest that stimulation of the selected B. subtilis strains in situ can contribute to mobilize entrapped oil in mature reservoirs. PMID:23911831

  3. Distillation pressure control

    Microsoft Academic Search

    Hofferber

    1988-01-01

    This patent describes an apparatus comprising: a fractional distillation column; means for providing a feed mixture to be fractionated to the column; means for withdrawing an overhead vapor stream from the column; means for condensing at least a portion of the overhead vapor stream; an accumulator; means for passing the resulting at least partially condensed overhead stream into the accumulator;

  4. Simultaneous biosorption of chromium(VI) and copper(II) on Rhizopus arrhizus in packed column reactor: Application of the competitive Freundlich model

    SciTech Connect

    Sag, Y.; Atacoglu, I.; Kutsal, T.

    1999-12-01

    The simultaneous biosorption of Cr(VI) and Cu(II) on free Rhizopus arrhizus in a packed column operated in the continuous mode was investigated and compared to the single metal ion situation. The breakthrough curves were measured as a function of feed flow rate, feed pH, and different combinations of metal ion concentrations in the feed solutions. Column competitive biosorption data were evaluated in terms of the maximum (equilibrium) capacity in the column, the amount of metal loading on the R. arrhizus surface, the adsorption yield, and the total adsorption yield. In the single-ion situation the adsorption isotherms were developed for optimum conditions, and it was seen that the adsorption equilibrium data fit the noncompetitive Freundlich model. For the multicomponent adsorption equilibrium the competitive adsorption isotherms were also developed. The competitive Freundlich model for binary metal mixtures represented most the column adsorption equilibrium data of Cr(VI) and Cu(II) on R. arrhizus satisfactorily.

  5. Axial mixing and mass transfer investigation in a pulsed packed liquid–liquid extraction column using plug flow and axial dispersion models

    Microsoft Academic Search

    Auob Safari; Jaber Safdari; Hossein Abolghasemi; Mostafa Forughi; Mahnaz Moghaddam

    In this research work, the volumetric overall mass transfer coefficient based on continuous-phase (Koca) and axial dispersion coefficients of phases (Ec, Ed) in a pilot Pulsed Packed Liquid Extraction Column (PPLEC) have been studied using plug flow model (PFM) and axial dispersion model (ADM). Experiments have been carried out using standard systems of water\\/acetone\\/toluene and water\\/acetone\\/n-butyl–acetate. Values of Koca evaluated

  6. On the extra-column band-broadening contributions of modern, very high pressure liquid chromatographs using 2.1 mm I.D. columns packed with sub-2 ?m particles

    Microsoft Academic Search

    Fabrice Gritti; Georges Guiochon

    The efficiencies of two narrow bore columns (100mm and 50mm×2.1mm) packed with 1.7?m totally porous BEH-C18 particles were measured on two very high pressure liquid chromatographs (Acquity from Waters and 1290 Infinity HPLC System from Agilent) operating at maximum pressures of 1034 and 1200bar, respectively. The probe compounds were a mixture of uracil, acetophenone, toluene, and naphthalene eluted in a

  7. Packed-column capillary electrochromatography and capillary electrochromatography-mass spectrometry using a lithocholic acid stationary phase.

    PubMed

    Norton, Dean; Shamsi, Shahab A

    2008-05-01

    The preparation and characterization of a novel lithocholic acid (LCA)-based liquid crystalline (LC) stationary phase (SP) suitable for application in packed-column CEC and CEC coupled to MS is described. The extent of bonding reactions of LCA-SP was assessed using 1H-NMR, 13C-NMR and elemental analysis. This characterization is followed by application of the LCA-SP for separation of beta-blockers, phenylethylamines (PEAs), polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Using the optimum mobile phase operating conditions (pH 3.0-4.5, 10 mM ammonium acetate, 85% v/v ACN), a comparison of the chromatographic ability of the aminopropyl silica phase vs. the LCA-bonded phase was conducted. The results showed improved selectivity for all test analytes using the latter phase. For example, the CEC-MS of beta-blockers demonstrated that the LCA-bonded phase provides separation of six out of seven beta-blockers, whereas the amino silica phase provides four peaks of several co-eluting beta-blockers. For the CEC-MS analysis of PEAs, the LCA-bonded phase showed improved resolution and different selectivity as compared to the aminopropyl phase. An evaluation of the retention trends for PEAs on both phases suggested that the PEAs were retained based on varying degree of hydroxyl substitution on the aromatic ring. In addition, the MS characterization shows several PEAs fragment in the electrospray either by loss of an alkyl group and/or by loss of H2O. Finally, the LCA-bonded phase displayed significantly higher separation selectivity for PAHs and PCBs as compared to the amino silica phase. PMID:18425746

  8. Design, optimization and performance of source and detector collimators for gamma-ray scanning of a lab-scale distillation column.

    PubMed

    Shahabinejad, H; Feghhi, S A H

    2015-05-01

    When using source and detector collimators for gamma ray column scanning, it is important to obtain an acceptable density profile quality. This paper consists of two main works. The first is devoted to describing the designs used to optimize the source and detector collimators for a lab-scale distillation column, and the second is devoted to investigating the effect of designed collimators on the quality of the density profiles obtained using the gamma scanning technique. Simulations using the MCNP4C Monte Carlo code were performed to model the collimators and obtain the density profiles. The source and detector collimator designs were developed for a cylindrical volume source with the energy of 0.662MeV and 1in.×1in. NaI, respectively. The pinhole and panoramic collimator designs and the pinhole and quartic collimator designs were considered for the source and the detector, respectively. The source container, with an opening angle of 60°, has the capability of substituting the collimator for high resolution, general and high sensitivity purposes. The pinhole collimator parameters for the source that were obtained were generally quite coarse and were 1.2cm in diameter and 4cm in length. Additionally, the detector pinhole collimator thickness and length obtained were 4cm and 5cm, respectively. Using the semi-quartic collimator for the detector, the weight of required lead was reduced by over 33% compared with the pinhole collimator. The simulation results of the column scanning in abnormal operation condition have been validated by experimental measurement results. The obtained results from scans demonstrated that the optimized panoramic source collimator and semi-quartic detector collimator in this study could help us to obtain an acceptable density profile quality in total count approach. PMID:25699665

  9. Comparison of performance of C18 monolithic rod columns and conventional C18 particle-packed columns in liquid chromatographic determination of Estrogel and Ketoprofen gel

    Microsoft Academic Search

    Lucie Nováková; Ludmila Matysová; Dagmar Solichová; Michael A. Koupparis; Petr Solich

    2004-01-01

    The performance of monolithic HPLC columns Chromolith™ (made by Merck, Germany) and conventional C18 columns Discovery (Supelco, Sigma–Aldrich, Prague, Czech Republic) was tested and the comparison for two topical preparations Ketoprofen gel and Estrogel gel was made. The composition of mobile phases – for Ketoprofen analysis a mixture of acetonitrile, water and phosphate buffer adjusted to pH 3.5 (40:58:2) and

  10. POTENTIAL ENERGY SAVINGS OF MULTIVESSEL BATCH DISTILLATION

    E-print Network

    Skogestad, Sigurd

    POTENTIAL ENERGY SAVINGS OF MULTIVESSEL BATCH DISTILLATION Bernd Wittgens and Sigurd Skogestad 1, Norway ABSTRACT ­ A conventional batch distillation column operated under feedback control applying the proposed policy is compared to the multivessel batch distillation column. In some cases we found

  11. Please cite this article in press as: Z. Li, H. Hong, Retardation of chromate through packed columns of surfactant-modified zeolite, J. Hazard. Mater. (2008), doi:10.1016/j.jhazmat.2008.06.061

    E-print Network

    Li, Zhaohui

    columns of surfactant-modified zeolite, J. Hazard. Mater. (2008), doi:10.1016/j.jhazmat.2008.elsevier.com/locate/jhazmat Retardation of chromate through packed columns of surfactant-modified zeolite Zhaohui Lia,b, , Hanlie Honga Available online xxx Keywords: Cationic surfactant Chromate Retardation Transport Zeolite a b s t r a c

  12. Catalytic distillation extends its reach

    SciTech Connect

    Rock, K.; McGuirk, T. [Catalytic Distillation Technologies, Houston, TX (United States); Gildert, G.R. [Catalytic Distillation Technologies, Pasadena, TX (United States)

    1997-07-01

    Since the early 1980s, catalytic distillation processes have been selected by more than a hundred operators for various applications. Since such a unit performs both reaction and distillation simultaneously, a combined column can replace a separate, fixed-bed reactor and distillation column, thereby eliminating equipment and reducing capital costs. And, compared to the conventional approach, catalytic distillation may also improve other factors, such as reactant conversion, selectivity, mass transfer, operating pressure, oligomer formation and catalyst fouling. The constant washing of the catalyst by liquid flowing down the column and the distillation of high-boiling foulants results in extended catalyst life. Four selective hydrogenation applications of catalytic distillation are discussed: Butadiene selective hydrogenation combined within an MTBE unit; Pentadiene selective hydrogenation; C{sub 4} acetylene conversion; and Benzene saturation.

  13. Combination of adsorption and biodegradation processes for textile effluent treatment using a granular activated carbon-biofilm configured packed column system.

    PubMed

    Ong, SoonAn; Toorisaka, Eiichi; Hirata, Makoto; Hano, Tadashi

    2008-01-01

    The objective of this study was to investigate the feasibility of using a granular activated carbon-biofilm configured packed column system in the decolorization of azo dye Acid Orange 7-containing wastewater. The Acid Orange 7-degrading microbial from anaerobic sequencing batch reactor which treating the azo dye-containing wastewater for more than 200 d was immobilized on spent granular activated carbon (GAC) through attachment. The GAC-biofilm configured packed column system showed the ability to decolorize 100% of the azo dye when working at high loading rate of Acid Orange 7 at 2.1 g/(L x d) with treatment time of 24 h. It was observed that the decolorization rate increased along with the increasing of initial Acid Orange 7 concentrations, until it reached an optimum point at about 0.38 g/h with initial Acid Orange 7 concentrations of 1,150 mg/L and the decolorization rate tend to be declined beyond this concentration. PMID:18817074

  14. Modelling reactive distillation

    Microsoft Academic Search

    R. Taylor; R. Krishna

    2000-01-01

    The design and operation issues for reactive distillation systems are considerably more complex than those involved for either conventional reactors or conventional distillation columns. The introduction of an in situ separation function within the reaction zone leads to complex interactions between vapor–liquid equilibrium, vapor–liquid mass transfer, intra-catalyst diffusion (for heterogeneously catalysed processes) and chemical kinetics. Such interactions have been shown

  15. Lipase-catalyzed reaction in the packed-bed reactor with continuous extraction column to overcome a product inhibition

    Microsoft Academic Search

    Sekyoo Jeong; Bum-Yeol Hwang; Juhan Kim; Byung-Gee Kim

    2000-01-01

    The resolution of rac-?-methyl-?-propiothiolactone (rac-MPTL) was performed in a packed-bed reactor (PBR) using Pseudomonas cepacia lipase (PCL) in organic media to produce enantiopure (R)-MPTL. By comparing enzyme stability of three enzyme forms, i.e. commercial PCL powder, Celite-immobilized PCL, and cross-linked enzyme crystals of PCL (CLECs-PCL), Celite-immobilized PCL was chosen for the construction of PBR because of its comparable stability to

  16. Investigation related to hydrogen isotopes separation by cryogenic distillation

    SciTech Connect

    Bornea, A.; Zamfirache, M.; Stefanescu, I.; Preda, A.; Balteanu, O.; Stefan, I. [INC-DTCI-ICSI Rm. Valcea, str.Uzinei, Nr.4, 240050 (Romania)

    2008-07-15

    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)

  17. High-performance liquid chromatographic column packings with different particle sizes: chromatographic behavior for the quality analysis of HuanglianShangqing pill.

    PubMed

    Yang, Dongzhi; Li, Ying; Yang, Fangxiu; Du, Yan; Li, Yinjie; Zheng, Xiaoxiao; Tang, Daoquan

    2015-02-01

    The chromatographic separation of traditional Chinese medicines is still a highly challenging task in analytical science with respect to its hundreds and thousands of chemical compounds, while increase of separation efficiency can greatly improve the separation power of chromatographic column for traditional Chinese medicine. In this study, 13 bioactive components in HuanglianShangqing pill were selected as an index to optimize the separation conditions and evaluate the system suitability of three commercially available columns packed with 1.8, 3.5, and 5.0 ?m particles. The chromatographic separations were obtained by the most appropriate Eclipse Plus C18 column (100 × 2.1 mm, 3.5 ?m) within 45 min using gradient elution with aqueous-ammonium acetate (10 mmol/L, pH 5.0) and acetonitrile, at a flow rate of 0.3 mL/min and an operating temperature of 30°C. The quality of HuanglianShangqing pill was assessed through combining simultaneous quantification of 13 compounds with fingerprint analysis. For the qualitative analysis, mass spectrometry was used to confirm the 13 compounds. All the validation data conformed to the acceptable requirements. For the fingerprint analysis, 32 peaks were selected as the common peaks at 254 nm to evaluate the similarities among HuanglianShangqing pills obtained from ten manufacturers. PMID:25447791

  18. CLOSED OPERATION OF MULTIVESSEL BATCH DISTILLATION -EXPERIMENTAL VERIFICATION

    E-print Network

    Skogestad, Sigurd

    1 CLOSED OPERATION OF MULTIVESSEL BATCH DISTILLATION - EXPERIMENTAL VERIFICATION Submitted to AICheÆcient operation, multicomponent distillation, batch distillation, total re ux operation ABSTRACT. The multivessel batch distillation column, as well as conven- tional batch distillation, may be operated in a closed

  19. MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS,

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS, EVA S RENSEN 3 and RAJAB distillation schemes, including the inverted column and the middle vessel column. The total re ux operation of the multivessel batch distillation column was presented recently, and the main contribution of this paper

  20. MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS,

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS, EVA SØRENSEN 3 and RAJAB distillation schemes, including the inverted column and the middle vessel column. The total reflux operation of the multivessel batch distillation column was presented recently, and the main contribution of this paper

  1. Synthesis and Development of Porous Polymeric Column Packing and Microchip Detectors for GC Analysis of Extraterrestrial Atmospheres

    NASA Technical Reports Server (NTRS)

    Shen, Thomas C.

    1999-01-01

    This report summarizes the last nine years research accomplishments under Cooperative Agreement NCC2-650 between NASA, Ames Research Center and SETI Institute. Four Major research tasks are conducted: 1. Gas chromatography column development. 2. Pyrosensor development. 3. Micro-machining gas chromatography instrument development. 4. Amino acid analysis and high molecular weight polyamino acid synthesis under prebiotic conditions. The following describes these results.

  2. Analysis and Control of Heteroazeotropic Batch Distillation

    E-print Network

    Skogestad, Sigurd

    Analysis and Control of Heteroazeotropic Batch Distillation S. Skouras and S. Skogestad Dept.interscience.wiley.com). The separation of close-boiling and azeotropic mixtures by heterogeneous azeotropic distillation is addressed. The results show that heteroazeotropic batch distillation exhibits substantial flexibility. The column profile

  3. Optimal distillation using thermodynamic geometry Bjarne Andresen

    E-print Network

    Salamon, Peter

    Optimal distillation using thermodynamic geometry Bjarne Andresen Ørsted Laboratory, University of a distillation column may be improved by permitting heat exchange on every tray rather than only in the reboiler (temperature, pressure, etc.) define successive states in a sequence of equilibria. Fractional distillation [2

  4. Ammonia removal from wastewaters using natural Australian zeolite. 2. Pilot-scale study using continuous packed column process

    SciTech Connect

    Cooney, E.L.; Booker, N.A.; Shallcross, D.C.; Stevens, G.W.

    1999-10-01

    A pilot-scale process was designed and operated to investigate the continuous removal of ammonia from sewage using natural zeolite from Australia. The process consisted of a fixed-bed ion-exchange system operated in the downflow mode. Evaluation of the pilot process was initially undertaken for ammonia removal from tap water spiked with ammonium chloride to provide performance data in the absence of competing cations. The performance of the pilot process was then assessed using sewage as feed. Breakthrough curves were constructed for a range of treatment flow rates. Existing models for packed bed performance were shown to be able to predict the breakthrough behavior of the process. The results of a study are presented that show that Australian natural zeolite, clinoptilolite, may be successfully employed in a fixed-bed ion-exchange process to achieve high ammonia removal efficiencies from aqueous solution at rates commensurate with sand filtration. The rate of uptake of ammonium by the zeolite is sufficient to support a continuous high rate process.

  5. Direct determination of Benzo[a]pyrene in oil distillates by on-line two-dimensional HPLC with column switching

    Microsoft Academic Search

    G. Lamprecht; J. F. K. Huber

    1992-01-01

    A selective and sensitive HPLC method for the determination of Benzo[a]pyrene (B[a]p) in oil fractions by means of column switching is described. The diluted oil samples were injected directly onto a silica column with isooctane as eluent. After fast elution of the main part of the sample matrix, the B[a]p containing fraction was transferred on-line to a dinitro-aryl-modified silica column

  6. Design of processes with reactive distillation line diagrams

    SciTech Connect

    Bessling, B. [BASF Ludwigshafen (Germany). Engineering Research and Development] [BASF Ludwigshafen (Germany). Engineering Research and Development; Schembecker, G.; Simmrock, K.H. [Univ. of Dortmund (Germany). Dept. of Chemical Engineering] [Univ. of Dortmund (Germany). Dept. of Chemical Engineering

    1997-08-01

    On the basis of the transformation of concentration coordinates, the concept of reactive distillation lines is developed. It is applied to study the feasibility of a reactive distillation with an equilibrium reaction on all trays of a distillation column. The singular points in the distillation line diagrams are characterized in terms of nodes and saddles. Depending on the characterization of the reactive distillation line diagrams, it can be decided whether a column with two feed stages is required. On the basis of the reaction space concept, a procedure for identification of reactive distillation processes is developed, in which the reactive distillation column has to be divided into reactive and nonreactive sections. This can be necessary to overcome the limitations in separation which result from the chemical equilibrium. The concentration profile of this combined reactive/nonreactive distillation column is estimated using combined reactive/nonreactive distillation lines.

  7. Repeatability of the efficiency of columns packed with sub-3?m core-shell particles: Part III. 2.7?m Poroshell 120 EC-C18 particles in 4.6mm and 2.1mm × 100mm column formats.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2012-08-24

    As part of an investigation of the column-to-column repeatability of the efficiency of columns packed with sub-3?m shell particles, the parameters of the mass transfer kinetics of twelve columns packed with the same batch of 2.7?m Poroshell 120 EC-C(18) particles (Agilent Technologies, Little Fall, DE, USA) were sequentially measured, using columns provided by the manufacturers that were representative of the efficiency distribution given by the quality test control. The reduced longitudinal diffusion term (B) was measured using the peak parking (PP) method; the reduced solid-liquid mass transfer resistance term (C) was given by a combination of the PP results and the most accurate model of effective diffusion in ternary composite materials. The overall eddy diffusion term (A) was obtained by subtraction of these two HETP terms from the overall reduced HETP derived from the peak moments measured by numerical integration of the entire peak profiles. The results demonstrate that the dispersion of the column efficiencies is a result of the random nature of the packing process and the eddy diffusion term resulting from the lack of homogeneity of the column bed. At the highest reduced velocity achieved for small analytes, the relative standard deviations (RSD) of the eddy diffusion term for the 2.1mm I.D. columns were ca. 3 and 11% (with average values h(eddy)= 2.5 and 13.5) for naphthalene (k=3) and uracil (k=0), respectively. For the 4.6mm I.D. columns, these RSDs were 5 and 13%, respectively, with average values h(eddy)= 1.4 and 2.9. For insulin at reduced velocities as high as 160, the RSDs of the total reduced plate heights were 3 and 8% for the 2.1 and 4.6mm I.D. columns, respectively. PMID:22683189

  8. Evaluating the interactions of organic compounds with multi-walled carbon nanotubes by self-packed HPLC column and linear solvation energy relationship.

    PubMed

    Chu, Yingqian; Li, Xuehua; Xie, Hongbin; Fu, Zhiqiang; Yang, Xianhai; Qiao, Xianliang; Cai, Xiyun; Chen, Jingwen

    2013-12-15

    Understanding the interactions between organic pollutants and carbon nanotubes (CNTs) is critical for fate assessment of both CNTs and organic pollutants. In this study, the chromatographic approach was introduced based on CNTs as stationary phase for the evaluation of such interactions. The pristine multi-walled carbon nanotubes (MWCNTs) were packed into columns of high-pressure liquid chromatography (HPLC) and the retention factors (k') were determined to characterize the adsorption affinity of organic compounds onto MWCNTs. Nine compounds were tested. The results showed that their lnk' values followed the order: benzene < toluene < phenol < chlorobenzene < bromobenzene < aniline < sulfamethoxazole < sulfadiazine ? sulfadimidine. The linear solvation energy relationship (LSER) theory was adopted to correlate lnk' with the molecular solvatochromic parameters. We found that lnk' of the studied compounds correlate positively with molecular polarizability (E) significantly, suggesting that the ?-/n-electrons-dependent polarizable interactions play a major role for the adsorption. Moreover, the thermodynamic parameters calculated from van't Hoff equations revealed that the interactions between the compounds and MWCNTs were spontaneous and exothermic processes. PMID:24231331

  9. Combination of a sub-3 ?m superficially porous particle packed column with charged aerosol detection for the simple and sensitive measurement of nine macrolides in human urine.

    PubMed

    Jia, Shaodong; Song, In Gi; Jeong, Kyung Min; Li, Jing; Park, Jeong Hill; Lee, Jeongmi; Kwon, Sung Won

    2014-10-01

    Due to the lack of chromophores in many macrolides, analytical methods based on mass spectrometry and electrochemical detection coupled to liquid chromatography have been suggested to be suitable for the quantification of macrolides in complex matrices. In this study, a simple and sensitive analytical method was established for the simultaneous measurement of nine macrolides in human urine by combining a sub-3 ?m superficially porous particle packed column with charged aerosol detection. After thorough investigation of various sample preparation methods, including two liquid-liquid extraction methods and four solid-phase extraction methods, HLB solid-phase extraction was selected and further optimized. Absolute recovery of the optimized sample preparation method ranged from 99.5-110.2%, indicating its very high extraction/clean-up efficiency. For chromatography, parameters influencing macrolide separation were systematically optimized, and the resulting conditions allowed baseline separation of nine macrolides within 24 min using a very simple mobile phase. The established method was validated for linearity, limit of detection, limit of quantification, absolute recovery, and precision. Based on its limit of detection (0.025-0.100 ?g/mL), the method had similar or greater sensitivity than most methods based on electrochemical detection. It was found that the current method was appropriate for application to real human urine samples after drug administration. PMID:25155847

  10. Determination of kinetic parameters in the biosorption of Cr (VI) on immobilized Bacillus cereus M(1)(16) in a continuous packed bed column reactor.

    PubMed

    Maiti, Soumen K; Bera, Debabrata; Chattopadhyay, Parimal; Ray, Lalitagauri

    2009-11-01

    Due to technological advancement, environment suffers from untreated toxic heavy metal bearing effluent coming from different industries. Chromium (VI) is one of those heavy metals having adverse impact on ecological balance, human, and plant health because of its carcinogenic properties. Biosorption is presented as an alternative to traditional technologies which are costly and inefficient for treatment of industrial wastes containing low amount of heavy metals. In this study, bioremediation of Cr (VI) ions by immobilized Bacillus cereus M(1) (16) was investigated in a laboratory scale packed bed up-flow column reactor. The effect of important parameters, such as the inlet flow rate, influent concentration, and effective bed height, has been studied. External mass transfer, surface adsorption, and intrabead mass transfer were also studied to conclude the rate limiting step for removal of Cr (VI) and to determine the process parameters which are important for biosorption optimization. The external mass transfer coefficient was calculated at different flow rates (6.51 x 10(-2) to 7.58 x 10(-2) cm/min). Using the model, the surface adsorption rate constant (k(ad)) and the intrabead mass transfer coefficient (k (i)) were predicted as 0.0267 x 10(-3) and 0.7465 x 10(-3) l/g/min, respectively. Both are much lower than the external mass transfer coefficient (k(e)). The surface adsorption phenomenon is acting as the rate-limiting step due to its high resistance for removal of Cr (VI). PMID:19333567

  11. A novel fiber-packed column for on-line preconcentration and speciation analysis of chromium in drinking water with flame atomic absorption spectrometry.

    PubMed

    Monasterio, Romina P; Altamirano, Jorgelina C; Martínez, Luis D; Wuilloud, Rodolfo G

    2009-02-15

    A novel on-line preconcentration and determination system based on a fiber-packed column was developed for speciation analysis of Cr in drinking water samples prior to its determination by flame atomic absorption spectrometry (FAAS). All variables involved in the development of the preconcentration method including, pH, eluent type, sample and eluent flow rates, interfering effects, etc., were studied in order to achieve the best analytical performance. A preconcentration factor of 32 was obtained for Cr(VI) and Cr(III). The levels of Cr(III) species were calculated by difference of total Cr and Cr(VI) levels. Total Cr was determined after oxidation of Cr(III) to Cr(VI) with hydrogen peroxide. The calibration graph was linear with a correlation coefficient of 0.999 at levels near the detection limit and up to at least 50 microg L(-1). The relative standard deviation (R.S.D.) was 4.3% (C=5 microg L(-1) Cr(VI), n=10, sample volume=25 mL). The limit of detection (LOD) for both Cr(III) and Cr(VI) species was 0.3 microg L(-1). Verification of the accuracy was carried out by the analysis of a standard reference material (NIST SRM 1643e "Trace elements in natural water"). The method was successfully applied to the determination of Cr(III) and Cr(VI) species in drinking water samples. PMID:19084637

  12. Effect of Number of Fractionating Trays on Reactive Distillation Performance

    E-print Network

    Al-Arfaj, Muhammad A.

    Effect of Number of Fractionating Trays on Reactive Distillation Performance Muhammad A. Al and rectifying sec- tions of a reacti®e distillation column can degrade performance. This effect, if true®e distillation columns cannot use conser®ati®e estimates of tray numbers, that is, we cannot simply add excess

  13. Multiple Steady States in Ideal Two-Product Distillation

    E-print Network

    Skogestad, Sigurd

    Multiple Steady States in Ideal Two-Product Distillation Elling W. Jacobsen and Sigurd Skogestad Chemical Engineering Dept., University of Trondheim-NTH, N-7034 Trondheim, Norway Simple distillation and compositions in the column. Introduction Multiple steady states (multiplicity) in distillation columns have

  14. MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS,

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS, EVA S RENSEN 3 and RAJAB distillation schemes. A simple feedback control strategy for the total re ux operation of a multivessel column distillation generally is less energy e cient than continuous distillation, it has received increased attention

  15. MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS,

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION 1 SIGURD SKOGESTAD 2 , BERND WITTGENS, EVA SØRENSEN 3 and RAJAB distillation schemes. A simple feedback control strategy for the total reflux operation of a multivessel column distillation generally is less energy efficient than continuous distillation, it has received increased

  16. Solar Ethanol Distillation Oara Neumann,1,3

    E-print Network

    O-9 Solar Ethanol Distillation Oara Neumann,1,3 Albert D. Neumann,2 Julius Müller,1 of separation, particularly distillation. The 40,000 commercial distillation columns in use in the U. S. consume or product purity. Distillation is the critical energy-consuming step accounting for 70-85% of the energy

  17. An extension of the multi-theta method to distillation columns and an almost band solution of the equilibrium stage problem

    E-print Network

    Gallun, Steven Eugene

    1975-01-01

    application of the Newton-Raphson procedure for such thermodynamic functions, and thus convergence properties typical of this method were obtained. The extended multiple theta method was then applied to a distillation problem involving thermodynamic... problem consists of N(2C + 3) equations in N(2C + 3) unknowns where C is the number of components and N the number of stages. Newman (1963) demonstrated a Newton-Raphson technique to converge the material balances based on choosing N stage temperatures...

  18. Repeatability of the efficiency of columns packed with sub-3?m core-shell particles: Part II. 2.7 ?m Halo-ES-Peptide-C18 particles in 4.6mm and 2.1mm×100mm column formats.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2012-08-24

    The column-to-column repeatability of the mass transfer kinetics in columns packed with sub-3?m shell particles was investigated. The parameters of this kinetics were measured for twelve columns (six 2.1mm×100mm and six 4.6mm×100mm) packed with the same batch of 2.7?m Halo-ES-Peptide-C(18) particles (Advanced Material Technologies, Wilmington, DE, USA). For both series, the manufacturer provided columns at different positions in the efficiency distribution given by the quality test control. Three compounds were used, uracil, naphthalene and insulin. The reduced longitudinal diffusion term was measured with the peak parking (PP) method; the reduced solid-liquid mass transfer resistance term was given by a combination of the PP results and the most accurate model of effective diffusion in ternary composite materials (non-porous cores, concentric porous shell, and eluent matrix), validated previously. The overall eddy diffusion term was obtained by subtraction of these two HETP terms from the overall reduced HETP measured by numerical integration of the entire peak profiles. The results demonstrate that the dispersion of the column efficiencies is mostly due to the random nature of the packing process and the associated eddy diffusion term. At the highest reduced velocity achieved, the relative standard deviations (RSDs) of the eddy diffusion term for the 2.1mm I.D. columns were ca. 5 and 10% (with average values A(?)=2.3 and 8.5) for naphthalene and uracil, respectively. For the 4.6mm I.D. columns, these RSDs were 3 and 5%, respectively, with average values A(?)=1.5 and 2.7. PMID:22687713

  19. Characterization of triglycerides in vegetable oils by silver-ion packed-column supercritical fluid chromatography coupled to mass spectroscopy with atmospheric pressure chemical ionization and coordination ion spray

    Microsoft Academic Search

    P. Sandra; A. Medvedovici; Y. Zhao; F. David

    2002-01-01

    Characterization of triglycerides in vegetable oils was achieved by silver-ion packed-column supercritical fluid chromatography (SI-pSFC) with mass spectrometric detection. Hyphenation was made using commercially available liquid chromatography–mass spectrometry (LC–MS) interfaces without any modification. A make-up fluid was delivered through a T-piece placed before or after the SFC restrictor by means of a high pressure pump. Atmospheric pressure chemical ionization (APCI)

  20. Solar Distillation

    Microsoft Academic Search

    Rahul Dev; Gopal Nath Tiwari

    \\u000a “Solar distillation” is a technology for producing potable water from brackish and underground water of low-quality at low\\u000a cost. It can reduce water-scarcity problems together with other water purification technologies. Solar distillation is analogous\\u000a to natural hydrological cycle. It uses an apparatus called a solar still in which water is evaporated using solar energy,\\u000a a form of renewable energy, and

  1. Distill, Distill_roll Distill for CASP10

    E-print Network

    Pollastri, Gianluca

    Distill, Distill_roll Distill for CASP10 C. Mirabello1, G. Tradigo1,2 , P.Veltri2, and G. Pollastri1 1 ­ UCD Dublin, Ireland, 2 ­ Università di Cosenza, Italy gianluca.pollastri@ucd.ie Distill has to the distance maps of templates rather than to predicted contact maps. The difference between Distill

  2. On applying model predictive control for distillation system of linear alkylbenzene (LAB) complex

    Microsoft Academic Search

    Xiaoming Jin; Gang Rong; Shuqing Wang

    2003-01-01

    This paper introduces industrial application via a commercial software of model predictive control (MPC) for distillation columns in a LAB plant, which consists of four distillation columns, HF acid stripper, benzene column, paraffin column, and LAB column in series. A MPC system in which is constructed of 12 controlled variables, 12 manipulated variables and 8 disturbance variables is developed to

  3. The adsorption of CO(2)/H(2)O/N(2) on 5A zeolite and silica gel in a packed column in one and two-dimensional flows

    NASA Astrophysics Data System (ADS)

    Mohamadinejad, Habib

    The purpose of this work is to develop a computer model that simulates the dynamic behavior of a Four-Bed Molecular Sieves (4-BMS) system. The system will be installed on the International Space Station for removal of CO 2/H2O/N2 on four beds that consist of 5A zeolite, 13X zeolite, and Silica gel. Due to the complexity of the actual 4-BMS, separately packed columns of 5A and Silica gel were built and tested using the model results to obtain the mass and heat transfer coefficients necessary for the development of the 4-BMS. This work begins by introducing the adsorption/desorption process in a packed column. The formulation of the simplest model of adsorption in a packed bed is developed assuming that Darcy's law. In this model, the mass and heat transport gradients are assumed to vary only in the axial direction, i.e., one-dimensional flow. The results of temperature and mass transfer breakthrough of one-dimensional flow are compared with the test results for adsorption of CO2/N2 and CO2/H2O/N2 on 5A zeolite. In the packed column near the wall boundary, the velocity decreases due to the viscous forces and the porosity increases exponentially. This near-wall region of higher porosity results in the channeling of fluid close to the wall surface. This channeling causes an early solute breakthrough relative to the center of the column. In order to accommodate the effect of porosity variation on the breakthrough, a two-dimensional model of the packed column is developed. The results of two-dimensional flow are compared with the test results for adsorption of CO2/N2 and CO2/H 2O/N2 on 5A zeolite. This work also investigates the dynamics of H2O adsorption on Silica gel material. A one-dimensional flow of a packed column bed is developed with the assumption that Darcy's law governs the momentum transport. The results of both models are compared with the test results for adsorption of H 2O/N2 on Silica gel. Finally, a computer model based on the obtained parameters of independent bench testing is developed to simulate the actual 4-BMS. The cyclical results of each bed of 4-BMS are presented to show the required time to reach the steady state operation. The experimental results from the laboratory scale-fixed bed adsorber are quantitatively consistent with the one-dimensional model at the center of the bed. The average concentration from the bed obtained from test results deviates from the column center concentration appreciably. This indicates the strong effects of porosity variation along the radial direction of the bed on the temperature, concentration, and velocity profile. The two-dimensional model not only accurately predicts the concentration and temperature profile at the column center, but it also predicts the average concentration reasonably well.

  4. Electric Driven Heat Pumps in Distillation Processes

    E-print Network

    Harris, G. E.

    1983-01-01

    Radian Corporation, under contract to the Electric Power Research Institute, has recently completed a study of the potential range of application for retrofitting electric driven heat pumps to existing distillation columns. A computerized evaluation...

  5. POTENTIAL ENERGY SAVINGS OF MULTIVESSEL BATCH DISTILLATION

    E-print Network

    Skogestad, Sigurd

    Norwegian University of Science and Technology NTNU, Department of Chemical Engineering, 7034 Trondheim, Norway ABSTRACT - A conventional batch distillation column operated under feedback control applying that an increase in production rate up to 50 is possible by using multivessel batch distillation instead

  6. Multivessel Batch Distillation -Potential Energy Savings

    E-print Network

    Skogestad, Sigurd

    Norwegian University of Science and Technology NTNU, Department of Chemical Engineering, 7034 Trondheim, Norway ABSTRACT - A conventional batch distillation column operated under feedback control applying that an increase in production rate up to 50 is possible by using multivessel batch distillation instead

  7. Distillation 29 Chem 355 Jasperse DISTILLATION

    E-print Network

    Jasperse, Craig P.

    Distillation 29 Chem 355 Jasperse DISTILLATION Background Distillation is a widely used technique for purifying liquids. The basic distillation process involves heating a liquid such that liquid molecules that is condensed and collected must be more pure than the original liquid mix. Distillation can be used to remove

  8. Membrane distillation

    Microsoft Academic Search

    Kevin W. Lawson; Douglas R. Lloyd

    1997-01-01

    This paper provides a state-of-the-art review of the separation process known as membrane distillation, MD. An introduction to the terminology and fundamental concepts associated with MD as well as a historical review of the developments in MD are presented. Membrane properties, transport phenomena, and module design are discussed in detail. A critical evaluation of the MD literature is incorporated throughout

  9. Analysis of Closed Multivessel Batch Distillation of Ternary Azeotropic Mixtures

    E-print Network

    Skogestad, Sigurd

    Analysis of Closed Multivessel Batch Distillation of Ternary Azeotropic Mixtures using Elementary) diagrams like distillation lines and isotherms maps may be used in analysis of the closed (total reflux) multivessel batch distillation column. An indirect level control strategy is implemented that eliminates

  10. Energy efficient distillation Ivar J. Halvorsen a,*, Sigurd Skogestad b

    E-print Network

    Skogestad, Sigurd

    Energy efficient distillation Ivar J. Halvorsen a,*, Sigurd Skogestad b a SINTEF ICT, Applied Keywords: Distillation Minimum energy Energy saving Dividing wall column Petlyuk arrangement Vmin-diagram a b s t r a c t Distillation is responsible for a significant amount of the energy consumption

  11. Distributive Distillation Enabled by Microchannel Process Technology

    SciTech Connect

    Arora, Ravi

    2013-01-22

    The application of microchannel technology for distributive distillation was studied to achieve the Grand Challenge goals of 25% energy savings and 10% return on investment. In Task 1, a detailed study was conducted and two distillation systems were identified that would meet the Grand Challenge goals if the microchannel distillation technology was used. Material and heat balance calculations were performed to develop process flow sheet designs for the two distillation systems in Task 2. The process designs were focused on two methods of integrating the microchannel technology â?? 1) Integrating microchannel distillation to an existing conventional column, 2) Microchannel distillation for new plants. A design concept for a modular microchannel distillation unit was developed in Task 3. In Task 4, Ultrasonic Additive Machining (UAM) was evaluated as a manufacturing method for microchannel distillation units. However, it was found that a significant development work would be required to develop process parameters to use UAM for commercial distillation manufacturing. Two alternate manufacturing methods were explored. Both manufacturing approaches were experimentally tested to confirm their validity. The conceptual design of the microchannel distillation unit (Task 3) was combined with the manufacturing methods developed in Task 4 and flowsheet designs in Task 2 to estimate the cost of the microchannel distillation unit and this was compared to a conventional distillation column. The best results were for a methanol-water separation unit for the use in a biodiesel facility. For this application microchannel distillation was found to be more cost effective than conventional system and capable of meeting the DOE Grand Challenge performance requirements.

  12. Distillations Podcast

    NSDL National Science Digital Library

    2012-09-14

    Created by the folks at the Chemical Heritage Foundation, Distillations is an award-winning podcast that offers commentary and perspective on the past, present, and future of chemistry. The program is hosted by Meir Rinde and new episodes are issued every other Friday. The archive here contains over 150 podcasts with titles such as "Shipwrecks," "Sweat," and "Something in the Air." Visitors can also sort through the documents by category and learn about the Distillations staff. The archives date back to 2007, so there's plenty to explore and visitors are free to use the materials as they see fit. An episode or two might be the perfect way to keep a group of students intrigued by the world of chemistry.

  13. Method for packing chromatographic beds

    DOEpatents

    Freeman, David H. (Potomac, MD); Angeles, Rosalie M. (Germantown, MD); Keller, Suzanne (Rockville, MD)

    1991-01-01

    Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.

  14. Hydrothermal carbonization of distiller’s grains

    Microsoft Academic Search

    Steven M. Heilmann; Lindsey R. Jader; Michael J. Sadowsky; Frederick J. Schendel; Marc G. von Keitz; Kenneth J. Valentas

    2011-01-01

    Wet distiller’s grains are intermediate byproducts of ethanol manufacture that have high moisture contents and require significant energy for drying and conversion into dry distiller’s grains. Hydrothermal carbonization was investigated as a wet process to provide alternative products, and chars were obtained in moderate yield that possessed high heats of combustion. The mechanism of char formation was also investigated employing

  15. Catalytic Distillation

    E-print Network

    Smith, L. A., Jr.; Hearn, D.; Wynegar, D. P.

    1984-01-01

    is continously removed by distillation as it is formed, thus substantially negating the reverse reaction. Also HeOR can be added directly to the reaction zone at a point where the isobutylene concentration is the lowest which also helps drive... the equilibrium forward toward HTBE formation. The net effect is equivalent to "multiple equilibrium stages" and almost total conversion of isobutylene to HTBE. Another possibili ty is to hold the IB in molar excess of HeOH and react HeOH to near extinction...

  16. Optimization of Distillation Processes. Jos A. Caballero* and Ignacio E. Grossmann**

    E-print Network

    Grossmann, Ignacio E.

    Optimization of Distillation Processes. José A. Caballero* and Ignacio E. Grossmann** *Dept and a single condenser in the entire sequence. We also review the rigorous design of distillation columns, or column sequences. In all the cases we focus on mathematical programming approaches. Keywords Distillation

  17. Optical resolution HPLC column packings carrying penicillin sulfoxide nucleus. Part II. Influence of the radical polymerization solvent on the optical resolution efficiency

    Microsoft Academic Search

    Y. Saotome; T. Miyazawa; T. Endo

    1989-01-01

    Polymethacrylamide carrying penicillin sulfoxide skeleton, poly(benzyl 1-oxo-6-methacrylaminopenicillanate) was synthesized in various solvents. Optical resolution efficiency of the high-performance liquid chromatography columns comprising the polymers was investigated. It was found that the radical polymerization solvent influenced the optical resolution capability of the resultant polymer, and that less hydrogen-bonding solvent was preferred for effective resolution.

  18. Effectiveness and longevity of a green/food waste derived compost packed column to reduce Cr(VI) contamination in groundwater.

    PubMed

    Piau, C; Aspray, T J

    2011-02-28

    PAS100 accredited compost derived from green and food waste sources was used to remediate groundwater containing Cr(VI) at a historically contaminated site in Falkirk, Scotland, UK. The compost was mixed with gravel at a ratio of 1:1 (v/v) to provide a reactive bedding material in an upflow column. The Cr(VI) concentration in the groundwater (inlet) ranged from 0.5 to 7.8 mg L(-1) during the 168 d trial period. After an acclimation period of 54 d, the flow rate was increased in the column from 5.8 to 8 mL min(-1). Cr(VI) in the outlet was less than 100 ?g L(-1) up to 134 d, after which the concentration steadily increased till 168 d. Compost analysis following completion of the trial confirmed that Cr(VI) was captured within the column. Anaerobic microbial reduction of Cr(VI) to Cr(III) was thought to be a key mechanism responsible for the longevity of the system to remove Cr(VI) from the groundwater. Requiring no additional organic carbon or nitrogen during the trial period, this setup represents a cost-effective treatment approach for low flow-through systems. PMID:21195546

  19. Distillation tray structural parameter study: Phase 1

    NASA Technical Reports Server (NTRS)

    Winter, J. Ronald

    1991-01-01

    The purpose here is to identify the structural parameters (plate thickness, liquid level, beam size, number of beams, tray diameter, etc.) that affect the structural integrity of distillation trays in distillation columns. Once the sensitivity of the trays' dynamic response to these parameters has been established, the designer will be able to use this information to prepare more accurate specifications for the construction of new trays. Information is given on both static and dynamic analysis, modal response, and tray failure details.

  20. Distillation sequence for the purification and recovery of hydrocarbons

    DOEpatents

    Reyneke, Rian (Katy, TX); Foral, Michael (Aurora, IL); Papadopoulos, Christos G. (Naperville, IL); Logsdon, Jeffrey S. (Naperville, IL); Eng, Wayne W. Y. (League City, TX); Lee, Guang-Chung (Houston, TX); Sinclair, Ian (Warrington, GB)

    2007-12-25

    This invention is an improved distillation sequence for the separation and purification of ethylene from a cracked gas. A hydrocarbon feed enters a C2 distributor column. The top of the C2 distributor column is thermally coupled to an ethylene distributor column, and the bottoms liquid of a C2 distributor column feeds a deethanizer column. The C2 distributor column utilizes a conventional reboiler. The top of the ethylene distributor is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor feeds a C2 splitter column. The ethylene distributor column utilizes a conventional reboiler. The deethanizer and C2 splitter columns are also thermally coupled and operated at a substantially lower pressure than the C2 distributor column, the ethylene distributor column, and the demethanizer column. Alternatively, a hydrocarbon feed enters a deethanizer column. The top of the deethanizer is thermally coupled to an ethylene distributor column, and the ethylene distributor column utilizes a conventional reboiler. The top of the ethylene distributor column is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor column feeds a C2 splitter column. The C2 splitter column operates at a pressure substantially lower than the ethylene distributor column, the demethanizer column, and the deethanizer column.

  1. Start | Grid View | Browse by Day OR Group/Topical | Author Index | Keyword Index | Personal Scheduler Active Constraint Regions for Economically Optimal Operation of Distillation

    E-print Network

    Skogestad, Sigurd

    Scheduler Active Constraint Regions for Economically Optimal Operation of Distillation Columns Tuesday and operation of distillation columns has been widely studied, as illustrated by for example Skogestad (1993 operation of distillation columns has been studied relatively little. The issue of active constraints

  2. Photocatalytic degradation of recalcitrant organic pollutants in water using a novel cylindrical multi-column photoreactor packed with TiO2-coated silica gel beads.

    PubMed

    Li, Dawei; Zhu, Qi; Han, Chengjie; Yang, Yingnan; Jiang, Weizhong; Zhang, Zhenya

    2015-03-21

    A novel cylindrical multi-column photocatalytic reactor (CMCPR) has been developed and successfully applied for the degradation of methyl orange (MO), amoxicillin (AMX) and 3-chlorophenol (3-CP) in water. Due to its higher adsorption capacity and simpler molecular structure, 3-CP compared with MO and AMX obtained the highest photodegradation (100%) and mineralization (78.1%) after 300-min photocatalytic reaction. Electrical energy consumption for photocatalytic degradation of MO, AMX and 3-CP using CMCPR was 5.79×10(4), 7.31×10(4) and 2.52×10(4) kW h m(-3) order(-1), respectively, which were less than one-thousand of those by reported photoreactors. The higher flow rate (15 mL min(-1)), lower initial concentration (5 mg L(-1)) and acidic condition (pH 3) were more favorable for the photocatalytic degradation of MO using CMCPR. Five repetitive operations of CMCPR achieved more than 97.0% photodegradation of MO in each cycle and gave a relative standard deviation of 0.72%. In comparison with reported slurry and thin-film photoreactors, CMCPR exhibited higher photocatalytic efficiency, lower energy consumption and better repetitive operation performance for the degradation of MO, AMX and 3-CP in water. The results demonstrated the feasibility of utilizing CMCPR for the degradation of recalcitrant organic pollutants in water. PMID:25528240

  3. On the performance of a cascade crossflow air stripping column

    SciTech Connect

    Akiyama, Y.; Valsaraj, K.T.; Wetzel, D.M.; Harrison, D.P. [Louisiana State Univ., Baton Rouge, LA (United States)] [Louisiana State Univ., Baton Rouge, LA (United States)

    1996-10-01

    The cascade crossflow packed column is an innovative design that offers the separation advantages of countercurrent flow while avoiding flooding limitations. Liquid and gas cross-sectional flow areas and path length in contact with packing may be controlled independently. These features are illustrated by studying the air stripping of methylene chloride (MeCl), 1,2-dichloroethane (1,2-DCA), and methyl ethyl ketone (MEK). Stripping efficiencies in the cascade crossflow column were generally slightly smaller than in countercurrent flow at equal liquid and gas flow rates. However larger gas-to-liquid ratios were possible in crossflow, permitting larger maximum stripping efficiencies to be attained. The experimental mass transfer coefficients were smaller than predicted by the Onda correlation. Modifications to the gas-phase Onda correlation are proposed that reduce the magnitude of the average deviation between experiment and prediction for 40 tests to about 12%. Experimental values of 38 of 40 tests were within {+-}30% of modified Onda correlation predictions. Additional applications for the cascade crossflow concept are suggested, such as vacuum distillation columns and trickle-bed reactors, which require low pressure drop and/or large gas-to-liquid ratios.

  4. Ind. Eng. Chem. Res. 1996,34, 4395-4405 4396 Multiple Steady States and Instability in Distillation. Implications

    E-print Network

    Skogestad, Sigurd

    Ind. Eng. Chem. Res. 1996,34, 4395-4405 4396 Multiple Steady States and Instability in Distillation-7034 Trondheim, Norway The fact that distillation columns, even in the ideal binary case, may display addresses some implications of these phenomena for the operation and control of distillation columns. Under

  5. Determination of chromium(VI) and lead in water samples by on-line sorption preconcentration coupled with flame atomic absorption spectrometry using a PCTFE-beads packed column.

    PubMed

    Anthemidis, Aristidis N; Koussoroplis, Salome-Juliette V

    2007-03-15

    A new time-based flow injection on-line solid phase extraction method for chromium(VI) and lead determination using flame atomic absorption spectrometry was developed. The use of hydrophobic poly-chlorotrifluoroethylene (PCTFE)-beads as absorbent in on-line preconcentration system was evaluated. Effective formation of ammonium pyrrolidine dithiocarbamate complexes and subsequently retention in PCTFE packed column, was achieved in pH range 1.0-1.6 and 1.5-3.2 for Cr(VI) and Pb(II) ions, respectively. The sorbed analyte was efficiently eluted with isobutyl-methyl-ketone for on-line FAAS determination. The proposed packing material exhibited excellent chemical and mechanical resistance, fast kinetics for adsorption of Cr(VI) and Pb(II) permitting the use of high sample flow rates at least up to 15mLmin(-1) without loss of retention efficiency. For a preconcentration time of 90s, the sample frequency was 30h(-1), the enhancement factor was 94 and 220, the detection limit was 0.4 and 1.2mugL(-1), while the precision (R.S.D.) was 1.8% (at 5mugL(-1)) and 2.1% (at 30mugL(-1)) for chromium(VI) and lead, respectively. The applicability and the accuracy of the developed method were estimated by the analysis spiked water samples and certified reference material NIST-CRM 1643d (Trace elements in water) and NIST-SRM 2109 (chromium(VI) speciation in water). PMID:19071515

  6. Complementarity, distillable secret key, and distillable entanglement

    E-print Network

    Masato Koashi

    2007-04-27

    We consider controllability of two conjugate observables Z and X by two parties with classical communication. The ability is specified by two alternative tasks, (i) agreement on Z and (ii) preparation of an eigenstate of X with use of an extra communication channel. We prove that their feasibility is equivalent to that of key distillation if the extra channel is quantum, and to that of entanglement distillation if it is classical. This clarifies the distinction between two entanglement measures, distillable key and distillable entanglement.

  7. Setting the Pressure at Which to Conduct a Distillation.

    ERIC Educational Resources Information Center

    Barduhn, Allen J.

    1984-01-01

    Discusses how pressure setting is determined for distillation columns, examining factors which must be considered when optimizing design for economical balance. Also discusses the basics of heat exchangers and cites a common problem with pressure differences. (JM)

  8. Distillation with Vapour Compression. An Undergraduate Experimental Facility.

    ERIC Educational Resources Information Center

    Pritchard, Colin

    1986-01-01

    Discusses the need to design distillation columns that are more energy efficient. Describes a "design and build" project completed by two college students aimed at demonstrating the principles of vapour compression distillation in a more energy efficient way. General design specifications are given, along with suggestions for teaching and…

  9. Vacuum distillation of ethanol. Final report

    SciTech Connect

    Weber, T.V.

    1982-01-01

    The objective was to determine whether distillation at or below a pressure of 70 mm of Hg would produce ethanol sufficiently anhydrous to permit mixing with gasoline without separation. The reason for this is that below 70 mm of Hg, the azeotrope does not form and, theoretically, 100% ethanol can be achieved by fractional distillation. There was insufficient information available to determine this by calculation. With the available experimental equipment, there were several problems (such as air leaks into the system, the vacuum pump was too small, temperature gradients in the column, condenser cooling water, etc.), but they did achieve reasonably anhydrous alcohol (99%). The distillation would require a heat source of about 140/sup 0/F (with a combination of simple and fractional distillation, a heat source of about 120/sup 0/F would suffice). These temperatures could be attained from a solar energy source for probably six months of the year. (LTN)

  10. DistillationTheory.fm 2 September 1999 Distillation Theory.

    E-print Network

    Skogestad, Sigurd

    1 DistillationTheory.fm 2 September 1999 Distillation Theory. by Ivar J. Halvorsen and Sigurd, Norway #12;2 DistillationTheory.fm 2 September 1999 Table of Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Material Balance on a Distillation Stage

  11. Pack Saddle

    USGS Multimedia Gallery

    This is a pack saddle used by Arnold Hague in the late 1800s. The wooden saddle has leather straps and a cinch used for the animal's comfort when carrying especially large loads. Pack saddles could be used to carry panniers or other large objects. Object ID: USGS-000014...

  12. On the Dynamics of Batch Distillation : A Study of Parametric Sensitivity in Ideal

    E-print Network

    Skogestad, Sigurd

    On the Dynamics of Batch Distillation : A Study of Parametric Sensitivity in Ideal Binary Columns distillation processes. By considering the e ect of small changes in the operating parameters, e.g., initial-mail: jacobsen@elixir.e.kth.se 1 #12;1 Introduction Batch distillation has become of increasing importance

  13. Control Study of Ethyl tert-Butyl Ether Reactive Distillation Muhammad A. Al-Arfaj

    E-print Network

    Al-Arfaj, Muhammad A.

    Control Study of Ethyl tert-Butyl Ether Reactive Distillation Muhammad A. Al-Arfaj Department structures for ethyl tert-butyl ether (ETBE) reactive distillation columns are studied. Two process The use of reactive distillation has grown in recent years because it results in less expensive and more

  14. On the Dynamics of Batch Distillation : A Study of Parametric Sensitivity in Ideal

    E-print Network

    Skogestad, Sigurd

    On the Dynamics of Batch Distillation : A Study of Parametric Sensitivity in Ideal Binary Columns sensitivity in batch distillation processes. By considering the effect of small changes in the operating #12; 1 Introduction Batch distillation has become of increasing importance in industry during the last

  15. MULTIVESSEL BATCH DISTILLATION SIGURD SKOGESTAD 1 , BERND WITTGENS, EVA SRENSEN 2

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION SIGURD SKOGESTAD 1 , BERND WITTGENS, EVA SØRENSEN 2 and RAJAB LITTO column presented in this paper provides a generalization of previously proposed batch distillation schemes. The economic potential of the multivessel batch distillation under total reflux is demon­ strated

  16. MULTIVESSEL BATCH DISTILLATION SIGURD SKOGESTAD 1 , BERND WITTGENS, EVA S RENSEN 2

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION SIGURD SKOGESTAD 1 , BERND WITTGENS, EVA S RENSEN 2 and RAJAB LITTO column presented in this paper provides a generalization of previously proposed batch distillation schemes. The economic potential of the multivessel batch distillation under total re ux is demon- strated

  17. MULTIVESSEL BATCH DISTILLATION -EXPERIMENTAL VERIFICATION Bernd Wittgens and Sigurd Skogestad1

    E-print Network

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION -EXPERIMENTAL VERIFICATION Bernd Wittgens and Sigurd Skogestad1 The experimental veri cation of the operation of a multivessel batch distillation column, operated under total re vessels, provides a generalization of previously proposed batch distillation schemes. We propose a simple

  18. Kinetic Method for Hydrogen-Deuterium-Tritium Mixture Distillation Simulation

    SciTech Connect

    Sazonov, A.B.; Kagramanov, Z.G.; Magomedbekov, E.P. [Mendeleyev University of Chemical Technology of Russia (Russian Federation)

    2005-07-15

    Simulation of hydrogen distillation plants requires mathematical procedures suitable for multicomponent systems. In most of the present-day simulation methods a distillation column is assumed to be composed of theoretical stages, or plates. However, in the case of a multicomponent mixture theoretical plate does not exist.An alternative kinetic method of simulation is depicted in the work. According to this method a system of mass-transfer differential equations is solved numerically. Mass-transfer coefficients are estimated with using experimental results and empirical equations.Developed method allows calculating the steady state of a distillation column as well as its any non-steady state when initial conditions are given. The results for steady states are compared with ones obtained via Thiele-Geddes theoretical stage technique and the necessity of using kinetic method is demonstrated. Examples of a column startup period and periodic distillation simulations are shown as well.

  19. Prevention and suppression of metal packing fires.

    PubMed

    Roberts, Mark; Rogers, William J; Sam Mannan, M; Ostrowski, Scott W

    2003-11-14

    Structured packing has been widely used because of large surface area that makes possible columns with high capacity and efficiency. The large surface area also contributes to fire hazards because of hydrocarbon deposits that can easily combust and promote combustion of the thin metal packing materials. Materials of high surface area that can fuel fires include reactive metals, such as titanium, and materials that are not considered combustible, such as stainless steel. Column design and material selection for packing construction is discussed together with employee training and practices for safe column maintenance and operations. Presented also are methods and agents for suppression of metal fires. Guidance for prevention and suppression of metal fires is related to incidents involving packing fires in columns. PMID:14602413

  20. Multipartite nonlocality distillation

    SciTech Connect

    Hsu, Li-Yi; Wu, Keng-Shuo [Department of Physics, Chung Yuan Christian University, Chungli 32023, Taiwan (China)

    2010-11-15

    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.

  1. Distillation: The Efficient Workhorse

    E-print Network

    Steinmeyer, D.

    DISTILLATION: THE EFFICIENT WORKHORSE Dan Steinmeyer Monsanto Company St. Louis, Missouri Distillation is inherently highly efficient: phase separation is clean it is relatively easy to build a mUltistage countercurrent device equilibrium... is closely approached on each stage Given the right perspective; the right application; and the right design - distillation is difficult to beat from an efficiency standpoint. ? The right perspective is that efficiency is the ratio of the work...

  2. Generalized entanglement distillation

    E-print Network

    Yu-Bo Sheng; Lan Zhou

    2014-04-14

    We present a way for the entanglement distillation of genuine mixed state. Different from the conventional mixed state in entanglement purification protocol, each components of the mixed state in our protocol is a less-entangled state, while it is always a maximally entangled state. With the help of the weak cross-Kerr nonlinearity, this entanglement distillation protocol does not require the sophisticated single-photon detectors. Moreover, the distilled high quality entangled state can be retained to perform the further distillation. These properties make it more convenient in practical applications.

  3. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, Jr., Edward M. (Friendswood, TX)

    1984-01-01

    A method 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 catatlyst 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.

  4. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, Jr., Edward M. (Friendswood, TX)

    1985-01-01

    A method and apparatus for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a 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.

  5. Design of Hybrid Distillation-Vapor Membrane Separation Systems. Jose A. Caballero*; Ignacio E. Grossmann **; Majid Keyvani+

    E-print Network

    Grossmann, Ignacio E.

    Design of Hybrid Distillation-Vapor Membrane Separation Systems. Jose A. Caballero*; Ignacio E (ethane, propane) on a commercial scale is performed almost exclusively by cryogenic distillation to optimize and retrofit a hybrid separation system consisting of a distillation column and a parallel

  6. Deterpenation of Brazilian orange peel oil by vacuum distillation

    Microsoft Academic Search

    Giane R. Stuart; Daíse Lopes; J. Vladimir Oliveira

    2001-01-01

    The deterpenation of orange peel oil in most industries is accomplished by vacuum distillation, but surprisingly little information\\u000a on this matter can be found in the open literature. This work reports recent results on orange peel oil deterpenation carried\\u000a out in an automatic vacuum distillation column operated in the semibatch mode at the temperatures of 50, 65, and 80C, at

  7. Advanced Distillation Final Report

    SciTech Connect

    Maddalena Fanelli; Ravi Arora; Annalee Tonkovich; Jennifer Marco; Ed Rode

    2010-03-24

    The Advanced Distillation project was concluded on December 31, 2009. This U.S. Department of Energy (DOE) funded project was completed successfully and within budget during a timeline approved by DOE project managers, which included a one year extension to the initial ending date. The subject technology, Microchannel Process Technology (MPT) distillation, was expected to provide both capital and operating cost savings compared to conventional distillation technology. With efforts from Velocys and its project partners, MPT distillation was successfully demonstrated at a laboratory scale and its energy savings potential was calculated. While many objectives established at the beginning of the project were met, the project was only partially successful. At the conclusion, it appears that MPT distillation is not a good fit for the targeted separation of ethane and ethylene in large-scale ethylene production facilities, as greater advantages were seen for smaller scale distillations. Early in the project, work involved flowsheet analyses to discern the economic viability of ethane-ethylene MPT distillation and develop strategies for maximizing its impact on the economics of the process. This study confirmed that through modification to standard operating processes, MPT can enable net energy savings in excess of 20%. This advantage was used by ABB Lumus to determine the potential impact of MPT distillation on the ethane-ethylene market. The study indicated that a substantial market exists if the energy saving could be realized and if installed capital cost of MPT distillation was on par or less than conventional technology. Unfortunately, it was determined that the large number of MPT distillation units needed to perform ethane-ethylene separation for world-scale ethylene facilities, makes the targeted separation a poor fit for the technology in this application at the current state of manufacturing costs. Over the course of the project, distillation experiments were performed with the targeted mixture, ethane-ethylene, as well as with analogous low relative volatility systems: cyclohexane-hexane and cyclopentane-pentane. Devices and test stands were specifically designed for these efforts. Development progressed from experiments and models considering sections of a full scale device to the design, fabrication, and operation of a single-channel distillation unit with integrated heat transfer. Throughout the project, analytical and numerical models and Computational Fluid Dynamics (CFD) simulations were validated with experiments in the process of developing this platform technology. Experimental trials demonstrated steady and controllable distillation for a variety of process conditions. Values of Height-to-an-Equivalent Theoretical Plate (HETP) ranging from less than 0.5 inch to a few inches were experimentally proven, demonstrating a ten-fold performance enhancement relative to conventional distillation. This improvement, while substantial, is not sufficient for MPT distillation to displace very large scale distillation trains. Fortunately, parallel efforts in the area of business development have yielded other applications for MPT distillation, including smaller scale separations that benefit from the flowsheet flexibility offered by the technology. Talks with multiple potential partners are underway. Their outcome will also help determine the path ahead for MPT distillation.

  8. Analysis of Breakthrough Profiles Based on Gamma Ray Emission Along Loaded Packed Bed Columns: Comparative Evaluation of Ionsiv IE-911 and Chabazite Zeolite for the Removal of Radiostrontium and Cesium from Groundwater

    SciTech Connect

    Bostick, D.T.; DePaoli, S.M.; Lucero, A.J.

    1999-10-18

    A gamma counting system has been assembled that can profile the breakthrough fronts of gamma-emitting radioisotopes longitudinally and axially along a loaded column. This profiling technique has been particularly useful in columns studies such as those performed with IONSP IE-911, a crystalline silicotitanate (CST) manufactured by UOP, in which unusually long operating times are required to observe cesium breakthrough in column effluent. The length of the mass transfer zone and extent of column saturation can be detected early in a column study by viewing the relative emission of gamma emitters along I the length of the column. In this study, gamma scans were used to analyze loaded CST and zeolite columns used in the treatment of process wastewater simulant and actual groundwater. Results indicate good run-to-run reproductibility in acquiring the scans. The longitudinal gamma scans for both {sup 90}Sr and {sup 137}Cs conformed with breakthrough results reported on the basis of column effluent activity. Although not obvious from data obtained by monitoring effluent activity, the gamma scans indicated that both cesium and strontium in the saturated zone of the CST column are slowly displaced by the higher levels of groundwater cations and are then resorbed further down the column. This displacement phenomenon identified by gamma scans was verified using data from a zeolite column, in which both the gamma scan and column effluent data exhibited radionuclide displacement by groundwater cations. The gamma emission intensities from the CST column runs are used to quantitate and compare the distribution coefficient and loading capacity of {sup 137}Cs on CST versus zeolite.

  9. Progressive separation scheme for crude oil distillation

    SciTech Connect

    Krueger, A.W. (American European Consulting Co. Inc., Houston, TX (US)); Gourlia, J.P.; Fromager, M. (Elf Aquitaine, Paris (FR))

    1989-01-01

    For many years now, crude distillation units have not been concerned with major technical improvements. Only the use of packing in the vacuum towers has allowed a greater efficiency for heavy products. The reduction of operating costs has been achieved by optimization of the heat exchanger network. The authors show the evolution of the ratio between the fuel consumption and the feed rate with the year of construction, for French refineries. The most efficient unit, the D.E.E. was built in 1980. The energy consumption is around 1.4% of the feedstock. The analysis of this recent unit shows that no significant improvement can be made without modifying the process itself. Therefore, the authors studied and designed a new process, called Progressive Crude Distillation. The first part of this paper is devoted to the analysis of conventional technology and the second part to their latest process. It demonstrates the economic interest of the Progressive Crude Distillation. The comparison is based on the study of a complex oil distillation scheme.

  10. Non-distillable entanglement guarantees distillable entanglement

    E-print Network

    Lin Chen; Masahito Hayashi

    2012-09-19

    The monogamy of entanglement is one of the basic quantum mechanical features, which says that when two partners Alice and Bob are more entangled then either of them has to be less entangled with the third party. Here we qualitatively present the converse monogamy of entanglement: given a tripartite pure system and when Alice and Bob are entangled and non-distillable, then either of them is distillable with the third party. Our result leads to the classification of tripartite pure states based on bipartite reduced density operators, which is a novel and effective way to this long-standing problem compared to the means by stochastic local operations and classical communications. Furthermore we systematically indicate the structure of the classified states and generate them. We also extend our results to multipartite states.

  11. Datalogging the Distillation Process.

    ERIC Educational Resources Information Center

    Soares, Allan; Creevy, Steven

    1995-01-01

    Presents a distillation experiment that uses temperature sensors connected to a computer in place of thermometers, and enables the whole class to view the data on a monitor and interpret and discuss the data in real time. (JRH)

  12. High-Purity Distillation

    Microsoft Academic Search

    DANIEL E. RIVERA; Hyunjin Lee; HANS D. MITTELMANN; MARTIN W. BRAUN

    2007-01-01

    Distillation is one of the most common separation techniques in chemical manufacturing. This multi-input, multi-output staged separation process is strongly interactive, as determined by the singular value decomposition of a linear dynamic model of the system. Process dynamics associated with the low-gain direction are critical to the design of high-performance controllers for high-purity distillation but are difficult to estimate from

  13. Random multiparty entanglement distillation

    E-print Network

    Ben Fortescue; Hoi-Kwong Lo

    2008-01-15

    We describe various results related to the random distillation of multiparty entangled states - that is, conversion of such states into entangled states shared between fewer parties, where those parties are not predetermined. In previous work [Phys. Rev. Lett. 98, 260501 (2007)] we showed that certain output states (namely Einstein-Podolsky-Rosen (EPR) pairs) could be reliably acquired from a prescribed initial multipartite state (namely the W state) via random distillation that could not be reliably created between predetermined parties. Here we provide a more rigorous definition of what constitutes ``advantageous'' random distillation. We show that random distillation is always advantageous for W-class three-qubit states (but only sometimes for Greenberger-Horne-Zeilinger (GHZ)-class states). We show that the general class of multiparty states known as symmetric Dicke states can be readily converted to many other states in the class via random distillation. Finally we show that random distillation is provably not advantageous in the limit of multiple copies of pure states.

  14. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 2012-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721...Substances § 721.4500 Isopropylamine distillation residues and ethylamine distillation...

  15. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2014-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721...Substances § 721.4500 Isopropylamine distillation residues and ethylamine distillation...

  16. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721...Substances § 721.4500 Isopropylamine distillation residues and ethylamine distillation...

  17. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721...Substances § 721.4500 Isopropylamine distillation residues and ethylamine distillation...

  18. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721...Substances § 721.4500 Isopropylamine distillation residues and ethylamine distillation...

  19. Valve Packing

    NASA Technical Reports Server (NTRS)

    1992-01-01

    "S Glass" yarn was originally developed by NASA for high temperature space and aeronautical applications. When John Crane, Inc. required material that would withstand temperatures higher than 1,200 degrees Fahrenheit, they contacted Owens-Corning, which had developed a number of applications for the material. John Crane combines the yarn with other components to make Style 287-I packing. The product can be used in chemical processing operations, nuclear power stations, petroleum products, etc. Advantages include increased service life and reduced maintenance costs.

  20. Winogradsky Columns

    NSDL National Science Digital Library

    John Lennox

    This is an exercise about Winogradsky Columns with emphasis placed on the formation and properties of microbial biofilms. It includes background reference material, a field/lab exercise, and several applications. Applications include methods for sampling column layers and a description of how to measure the electro-chemical gradient that develops within the column. Scientific illustrations and images are included as visual references.

  1. APPLICATION OF CAPILLARY SUPERCRITICAL FLUID CHROMATOGRAPHY TO THE ANALYSIS OF A MIDDLE DISTILLATE FUEL

    EPA Science Inventory

    The paper describes the application of capillary supercritical fluid chromatography (SFC) to the analysis of a middle distillate fuel. Small diameter (50 micrometer i.d.) fused silica capillary columns coated with crosslinked 50% phenyl polymethylsiloxane provided high separation...

  2. Qutrit Magic State Distillation

    E-print Network

    Anwar, Hussain; Browne, Dan E

    2012-01-01

    Magic state distillation (MSD) is a purification protocol that plays a central role in fault tolerant quantum computation. Repeated iteration of the steps of a MSD protocol, generates pure single non-stabilizer states, or magic states, from multiple copies of a mixed resource state using stabilizer operations only. Thus mixed resource states promote the stabilizer operations to full universality. Magic state distillation was introduced for qubit-based quantum computation, but little has been known concerning MSD in higher dimensional qudit-based computation. Here, we describe a general approach for studying MSD in higher dimensions. We use it to investigate the features of a qutrit MSD protocol based on the 5-qutrit stabilizer code. We show that this protocol distills non-stabilizer magic states, and identify two types of states, that are attractors of this iteration map. Finally, we show how these states may be converted, via stabilizer circuits alone, into a state suitable for state injected implementation ...

  3. Reactive Distillation and Air Stripping Processes for Water Recycling and Trace Contaminant Control

    NASA Technical Reports Server (NTRS)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Reactive distillation designs are considered to reduce the presence of volatile organic compounds in the purified water. Reactive distillation integrates a reactor with a distillation column. A review of the literature in this field has revealed a variety of functional reactive columns in industry. Wastewater may be purified by a combination of a reactor and a distiller (e.g., the EWRS or VPCAR concepts) or, in principle, through a design which integrates the reactor with the distiller. A review of the literature in reactive distillation has identified some different designs in such combinations of reactor and distiller. An evaluation of reactive distillation and reactive air stripping is presented with regards to the reduction of volatile organic compounds in the contaminated water and air. Among the methods presented, an architecture is presented for the evaluation of the simultaneous oxidation of organics in air and water. These and other designs are presented in light of potential improvements in power consumptions and air and water purities for architectures which include catalytic activity integrated into the water processor. In particular, catalytic oxidation of organics may be useful as a tool to remove contaminants that more traditional distillation and/or air stripping columns may not remove. A review of the current leading edge at the commercial level and at the research frontier in catalytically active materials is presented. Themes and directions from the engineering developments in catalyst design are presented conceptually in light of developments in the nanoscale chemistry of a variety of catalyst materials.

  4. Experimental and Numerical Investigation of Two Dimensional CO2 Adsorption/Desorption in Packed Sorption Beds under Non-Ideal Flows

    NASA Technical Reports Server (NTRS)

    Mohamadinejad, H.; Knox, J. C.; Smith, J. E.; Croomes, Scott (Technical Monitor)

    2001-01-01

    The experimental results of CO2 adsorption and desorption in a packed column indicated that the concentration wave front at the center of the packed column differs from those which are close to the wall of column filled with adsorbent material even though the ratio of column diameter to the particle size is greater than 20. The comparison of the experimental results with one dimensional model of packed column shows that in order to simulate the average breakthrough in a packed column a two dimensional (radial and axial) model of packed column is needed. In this paper the mathematical model of a non-slip flow through a packed column with 2 inches in diameter and 18 inches in length filled with 5A zeolite pellets is presented. The comparison of experimental results of CO2 absorption and desorption for the mixed and central breakthrough of the packed column with numerical results is also presented.

  5. Efficient distillation beyond qubits

    E-print Network

    K. G. H. Vollbrecht; M. M. Wolf

    2002-08-26

    We provide generalizations of known two-qubit entanglement distillation protocols for arbitrary Hilbert space dimensions. The protocols, which are analogues of the hashing and breeding procedures, are adapted to bipartite quantum states which are diagonal in a basis of maximally entangled states. We show that the obtained rates are optimal, and thus equal to the distillable entanglement, for a (d-1) parameter family of rank deficient states. Methods to improve the rates for other states are discussed. In particular, for isotropic states it is shown that the rate can be improved such that it approaches the relative entropy of entanglement in the limit of large dimensions.

  6. Low Energy Distillation Schemes

    E-print Network

    Polley, G. T.

    of reducing energy consumption. We look at how the better integrated distillation schemes can be quickly identified. It is found that the design of integrated schemes is quicker than that of non-integrated schemes. We then look at how the use of heat pumps...

  7. Tritium Attenuation by Distillation

    SciTech Connect

    Wittman, N.E.

    2001-07-31

    The objective of this study was to determine how a 100 Area distillation system could be used to reduce to a satisfactory low value the tritium content of the dilute moderator produced in the 100 Area stills, and whether such a tritium attenuator would have sufficient capacity to process all this material before it is sent to the 400 Area for reprocessing.

  8. Topological Quantum Distillation

    E-print Network

    H. Bombin; M. A. Martin-Delgado

    2007-03-29

    We construct a class of topological quantum codes to perform quantum entanglement distillation. These codes implement the whole Clifford group of unitary operations in a fully topological manner and without selective addressing of qubits. This allows us to extend their application also to quantum teleportation, dense coding and computation with magic states.

  9. The distillability problem revisited

    E-print Network

    Lieven Clarisse

    2006-07-19

    An important open problem in quantum information theory is the question of the existence of NPT bound entanglement. In the past years, little progress has been made, mainly because of the lack of mathematical tools to address the problem. (i) In an attempt to overcome this, we show how the distillability problem can be reformulated as a special instance of the separability problem, for which a large number of tools and techniques are available. (ii) Building up to this we also show how the problem can be formulated as a Schmidt number problem. (iii) A numerical method for detecting distillability is presented and strong evidence is given that all 1-copy undistillable Werner states are also 4-copy undistillable. (iv) The same method is used to estimate the volume of distillable states, and the results suggest that bound entanglement is primarily a phenomenon found in low dimensional quantum systems. (v) Finally, a set of one parameter states is presented which we conjecture to exhibit all forms of distillability.

  10. Heteroazeotropic Batch Distillation Feasibility and Operation

    E-print Network

    Skogestad, Sigurd

    Heteroazeotropic Batch Distillation Feasibility and Operation by Efstathios Skouras and distillation is the dominating unit operation for such separations. However, the presence of azeotropes and non distillation as the best suited process. Among, various techniques to enhance distillation, heterogeneous

  11. On bound entanglement assisted distillation

    E-print Network

    V. Vedral

    1999-11-17

    We investigate asymptotic distillation of entanglement in the presence of an unlimited amount of bound entanglement for bi-partite systems. We show that the distillability is still bounded by the relative entropy of entanglement. This offers a strong support to the fact that bound entanglement does not improve distillation of entanglement.

  12. Serum Injection of the HPLC Column for Carbamazepine Assay

    Microsoft Academic Search

    Z. K. Shihabi; R. D. Dyer

    1987-01-01

    Serum was injected directly on an HPLC column packed with C1, 6.5 ?m particle size, 300 Å pore-packing material for carbamazepine determination. The use of a wide-pore column with low hydrophobicity eliminated excessive pressure buildup in the column from protein precipitation which is usually caused by the high concentration of organic solvents in the mobile phase. This simple approach can

  13. A critical review of dispersion in packed beds

    NASA Astrophysics Data System (ADS)

    Delgado, J. M. P. Q.

    2006-02-01

    The phenomenon of dispersion (transverse and longitudinal) in packed beds is summarized and reviewed for a great deal of information from the literature. Dispersion plays an important part, for example, in contaminant transport in ground water flows, in miscible displacement of oil and gas and in reactant and product transport in packed bed reactors. There are several variables that must be considered, in the analysis of dispersion in packed beds, like the length of the packed column, viscosity and density of the fluid, ratio of column diameter to particle diameter, ratio of column length to particle diameter, particle size distribution, particle shape, effect of fluid velocity and effect of temperature (or Schmidt number). Empirical correlations are presented for the prediction of the dispersion coefficients ( D T and D L) over the entire range of practical values of Sc and Pem, and works on transverse and longitudinal dispersion of non-Newtonian fluids in packed beds are also considered.

  14. Cascade Distillation System Development

    NASA Technical Reports Server (NTRS)

    Callahan, Michael R.; Sargushingh, Miriam; Shull, Sarah

    2014-01-01

    NASA's Advanced Exploration Systems (AES) Life Support System (LSS) Project is chartered with de-veloping advanced life support systems that will ena-ble NASA human exploration beyond low Earth orbit (LEO). The goal of AES is to increase the affordabil-ity of long-duration life support missions, and to re-duce the risk associated with integrating and infusing new enabling technologies required to ensure mission success. Because of the robust nature of distillation systems, the AES LSS Project is pursuing develop-ment of the Cascade Distillation Subsystem (CDS) as part of its technology portfolio. Currently, the system is being developed into a flight forward Generation 2.0 design.

  15. Well packing system

    Microsoft Academic Search

    Drnevich

    1990-01-01

    This patent describes a packing structure and method of packing which can be used in the wellbore of injection wells for the recovery of heavy oils, shale oils, and tars, and in well shafts for in-situ coal gasification. The packing can also be used in the wellbore of gas and light oil production wells. The packing is used to provide

  16. Distillation of hydrogen isotopes for polarized HD targets

    NASA Astrophysics Data System (ADS)

    Ohta, T.; Bouchigny, S.; Didelez, J.-P.; Fujiwara, M.; Fukuda, K.; Kohri, H.; Kunimatsu, T.; Morisaki, C.; Ono, S.; Rouillé, G.; Tanaka, M.; Ueda, K.; Uraki, M.; Utsuro, M.; Wang, S. Y.; Yosoi, M.

    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 2 ( ˜0.01%) in the HD gas plays an important role in efficiently polarizing the HD target. Since there are 1-5% impurities of H 2 and D 2 in commercially available HD gases, it is necessary to purify the HD gas up to ˜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 2 to the purified HD gas.

  17. Self-regenerating column chromatography

    DOEpatents

    Park, W.K.

    1995-05-30

    The present invention provides a process for treating both cations and anions by using a self-regenerating, multi-ionic exchange resin column system which requires no separate regeneration steps. The process involves alternating ion-exchange chromatography for cations and anions in a multi-ionic exchange column packed with a mixture of cation and anion exchange resins. The multi-ionic mixed-charge resin column works as a multi-function column, capable of independently processing either cationic or anionic exchange, or simultaneously processing both cationic and anionic exchanges. The major advantage offered by the alternating multi-function ion exchange process is the self-regeneration of the resins.

  18. Effect of Recycle Streams on Energy Performance and Closed Loop Dynamics of Distillation Sequences

    E-print Network

    S. Hernández A; J. G. Segovia-hernández A; J. Carlos Cárdenas A; V. Rico-ramírez B

    This paper presents the retrofit of five conventional distillation trains for the separation of quaternary mixtures of hydrocarbons for feed compositions with high or low content of intermediate components. The retrofit implies the incorporation of liquid or vapour recycle streams among the conventional distillation columns. Each recycle stream removes one condenser or one reboiler. The introduction of thermal links can lower the energy consumption up to 40 % in contrast to conventional distillation trains widely used in the industry. This efficiency in the use of energy is achieved because the recycle streams, introduced in the conventional distillation trains, reduce the remixing associated with higher energy consumption. Also, the introduction of recycle streams can improve the dynamic responses in contrast to those obtained in the conventional distillation sequences. Hence, the introduction of recycle streams in the conventional distillation sequences can improve both the energy consumption and the control properties.

  19. Synthesis of metronidazole-imprinted molecularly imprinted polymers by distillation precipitation polymerization and their use as a solid-phase adsorbent and chromatographic filler.

    PubMed

    Liu, Jiang; Zhang, Lu; Li Han Song, Le; Liu, Yuan; Tang, Hui; Li, Yingchun

    2015-04-01

    Metronidazole-imprinted polymers with superior recognition properties were prepared by a novel strategy called distillation-precipitation polymerization. The as-obtained polymers were characterized by Fourier-transform infrared spectroscopy, laser particle size determination and scanning electron microscopy, and their binding performances were evaluated in detail by static, kinetic and dynamic rebinding tests, and Scatchard analysis. The results showed that when the fraction of the monomers was 5 vol% in the whole reaction system, the prepared polymers afforded good morphology, monodispersity, and high adsorption capacity and excellent selectivity to the target molecule, metronidazole. The optimal binding performance is 12.41 mg/g for metronidazole just before leakage occurred and 38.51 mg/g at saturation in dynamic rebinding tests. Metronidazole-imprinted polymers were further applied as packing agents in solid-phase extraction and as chromatographic filler, both of which served for the detection of metronidazole in fish tissue. The results illustrated the recoveries of spiked samples ranged from 82.97 to 87.83% by using molecularly imprinted solid-phase extraction combined with a C18 commercial column and 93.7 to 101.2% by directly using the polymer-packed chromatographic column. The relative standard deviation of both methods was less than 6%. PMID:25594306

  20. Method for making a non-extractable stationary phase of polymer within a capillary column

    DOEpatents

    Springston, S.R.

    1990-10-30

    A method is described for coating interior capillary column surfaces, or packing material of a packed column, used for gas chromatography, with a stationary polymer phase that is cross-linked by exposing it to a low-temperature plasma that is uniformly distributed over the column or packing material for a predetermined period of time to effect the desired degree of cross-linking of the coating. 7 figs.

  1. Method for making a non-extractable stationary phase of polymer within a capillary column

    DOEpatents

    Springston, Stephen R. (Middle Island, NY)

    1990-01-01

    A method for coating interior capillary column surfaces, or packing material of a packed column, used for gas chromatography, with a stationary polymer phase that is cross-linked by exposing it to a low-temperature plasma that is uniformly distributed over the column or packing material for a predetermined period of time to effect the desired degree of cross-linking of the coating.

  2. Trajan's Column

    NSDL National Science Digital Library

    This Website, from McMaster University, uses the combined skills of artists, writers, programmers, and Web designers to create a resource for the study of Trajan's column, a Roman architectural monument. This 100-foot marble column, built during the reign of Emperor Trajan, 98-117 AD, is topped with a gilded statue of Trajan and decorated with carvings recounting Trajan's rule, primarily the Dacian Wars and his building projects. The heart of the Website is the database of 500 slides of the carvings; indexes allow users to view the slides in thematic groupings such as images of sides of the column, groups organized by subject keywords, or carvings made with specific tools. Cartoons or drawings of the column help to contextualize the details found in the slides, and essays provide more information on its design, construction, and preservation.

  3. Graphically find theoretical trays and minimum reflux for Complex multicomponent distillation

    Microsoft Academic Search

    Kister

    1985-01-01

    The article describes a procedure which provides the means for making the preliminary design of a distillation column and for analyzing column design and performance. Its development follows the steps of Hengstebeck's derivation for a simple, single-feed fractionator. For each feed, all the light nonkeys introduced end up in the rising vapor, and all the heavy nonkeys in the descending

  4. Thermomechanically integrated distillation of ethylene from ethane

    SciTech Connect

    Greene, D.G.; Haddad, H.; Manley, D.B. [Univ. of Missouri, Rolla, MO (United States)

    1994-12-31

    The separation of ethylene from ethane by distillation is normally the final step in the production of ethylene. The critical temperature of ethylene is about 50 F, therefore moderately low temperatures and moderately high pressures are typically used to provide optimum economic conditions. The optimum design can require thick walled and heavy pressure vessels which may be constructed of expensive alloy steels depending on the specific operating conditions. The required purity of ethylene usually exceeds 99.9%, and the economic level of recovery is approximately 99%. In addition, the relative volatility of ethylene to ethane is moderately small ranging from about 1.13 for high pressure mixtures rich in ethylene to 2.34 for low pressure mixtures rich in ethane. The relatively high purity and recovery and relatively low relative volatility dictate a large distillation column with more than 100 trays and a large diameter for world scale production levels of over a billion pounds per year of ethylene. The installed capital cost for a unit of this type and size can exceed twenty million dollars, and utility costs can exceed one million dollars per year. Consequently, there is a strong economic incentive to reduce costs through improved process designs for the distillation of ethylene from ethane, and the process is well studied in the literature. Thermomechanically integrated distillation provides an improved design which can reduce both capital and operating costs as compared to the best conventional designs. In this paper, the conventional designs for both vapor and liquid feeds are reviewed, the underlying thermodynamics characterizing the process is discussed, alternative thermomechanically integrated designs are presented, and utility and purchased equipment costs are compared.

  5. Systems and methods for reactive distillation with recirculation of light components

    DOEpatents

    Stickney, Michael J. (Nassau Bay, TX); Jones, Jr., Edward M. (Friendswood, TX)

    2011-07-26

    Systems and methods for producing gas-to-liquids products using reactive distillation are provided. The method for producing gas-to-liquids products can include reacting a feedstock in a column having a distillation zone and a reaction zone to provide a bottoms stream and an overhead stream. A first portion of the overhead stream can be recycled to the column at the top of the reaction zone and second portion of the overhead stream can be recycled to the column at the bottom of the reaction zone.

  6. Determination of plate efficiencies for conventional distillation columns

    E-print Network

    Harris, Thomas Raymond

    1962-01-01

    8 Convergence Method ~ ~ 0 ~ ~ 0 ~ 29 Treatment of Systems Containing Relatively Light and Heavy Components . Illustrative Examples Conclusions 58 40 45 Table of Notation ~ ~ ~ I 0 t 0 0 ~ 46 Bibliography . 52 Appendiz 56 LIST... efficiency for bensene in a bensene-toluene system decreased. For aqueous and 11 hydrocarbon solutions, Gunnes and Baker (26), Nord (47), and Wi)k and Thyssen (66) noted sharp decreases in plate efficiency for a component when it was present in small...

  7. Optimization approach to entanglement distillation

    E-print Network

    T. Opatrny; G. Kurizki

    1999-04-09

    We put forward a method for optimized distillation of partly entangled pairs of qubits into a smaller number of more entangled pairs by recurrent local unitary operations and projections. Optimized distillation is achieved by minimization of a cost function with up to 30 real parameters, which is chosen to be sensitive to the fidelity and the projection probability at each step. We show that in many cases this approach can significantly improve the distillation efficiency in comparison to the present methods.

  8. Heat Transfer Analysis of a Packed Bed-PCM Capsules Latent Heat Thermal Energy Storage System

    Microsoft Academic Search

    Z. S. Abdel-Rehim

    2011-01-01

    Heat transfer analysis of a packed bed-PCM latent heat thermal energy storage system is presented in this study. The packed bed cylindrical column is filled with spherical capsules of PCM (paraffin wax) that is used for a solar water heating application. In this study, the physical model is developed to use for analyzing the thermal performance of packed bed-PCM latent

  9. Heavy oil distillation system

    SciTech Connect

    Heaney, W.F.; Nitsch, A.R.

    1988-04-12

    A method for increasing the amount of volatiles produced and decreasing the amount of coke produced from a fixed amount of a vacuum reduced crude from a vacuum distillation tower is described comprising: (a) feeding the vacuum reduced crude from the vacuum distillation tower directly into a coker combination tower; (b) coking a residuum stripped of volatiles generating coke drum vapor; (c) feeding the coke drum vapor into the coker combination tower in contact with and in direct countercurrent heat exchange relationship with the vacuum reduced crude in the coker combination tower whereby some of the coke drum vapor is absorbed by the vacuum-reduced crude generating a coker combination tower residuum; (d) feeding the coker combination tower residuum into a resid flash down tower maintained at a pressure below the pressure in the coker combination tower; (e) fractionating the coker combination tower residuum in flash down tower into a vapor stream and a liquid stream comprising a residuum stripped of volatiles; (f) feeding the residuum stripped of volatiles to a delayed coke drum and coking the resdiuum stripped of volatiles as provided in step (b); condensing the fractionated vapor stream.

  10. Application of sidestream recycle to the separation of hydrogen isotopes by cryogenic distillation

    Microsoft Academic Search

    R. P. Sherman; D. J. Taylor; J. W. Barnes; T. Yamanishi; M. Enoeda; S. Konishi; K. Okuno

    1993-01-01

    Withdrawal of a sidestream from an isotopic separation distillation column followed by equilibration of species and reinjection is a technique for reducing the required number of columns and hence reducing tritium inventories in fusion-energy fuel processing systems. Measurements have been made with a single column and the three-component H2-HD-D2 system withdrawing streams of essentially pure H2 and D2. This was

  11. Israelachvili Packing factor

    NSDL National Science Digital Library

    Iacovella, Christopher R.

    2006-08-02

    Israelachvili Packing factor. The geometry of associated structures depends upon "packing" properties of the molecule: the optimal area of the head group, a0, volume of the chain, V, and the critical length of the tether, lc.

  12. Almost Square Packing

    Microsoft Academic Search

    Helmut Simonis; Barry O’Sullivan

    2011-01-01

    \\u000a The almost square rectangle packing problem involves packing all rectangles with sizes 1 ×2 to n ×(n?+?1) (almost squares) into an enclosing rectangle of minimal area. This extends the previously studied square packing problem\\u000a by adding an additional degree of freedom for each rectangle, deciding in which orientation the item should be packed. We\\u000a show how to extend the model

  13. On Discrete Hyperbox Packing

    E-print Network

    Li, Xiafeng

    2010-01-14

    Bin packing is a very important and popular research area in the computer science field. Past work showed many good and real-world packing algorithms. How- ever, due to the complexity of the problem in multiple-dimensional bin packing, also called...

  14. The role of ionic strength and grain size on the transport of colloids in unsaturated sand columns

    NASA Astrophysics Data System (ADS)

    Mitropoulou, Polyxeni N.; Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

    2013-04-01

    The main objective of this study was to better understand the combined effects of ionic strength, and sand grain size on colloid fate and transport in unsaturated porous media. Spherical fluorescent polymer microspheres with three different sizes (0.075, 0.30 and 2.1 ?m), and laboratory columns packed with two size fractions of clean quartz sand (0.513 and 0.181 mm) were used. The saturation level of the packed columns was set to 83-95% with solutions having a wide range of ionic strength (0.1-1000 mM). The electrophoretic mobility of colloids and sand grains were evaluated for all the experimental conditions employed. The various experimental collision efficiencies were quanti?ed using the classical colloid ?ltration theory. The theoretical collision efficiencies were estimated with appropriate DLVO energies using a Maxwell model. The experimental results suggested that the retention of the bigger colloids (2.1 ?m) was slightly higher compared to the conservative tracer and smaller colloids (0.3 and 0.075 ?m) in deionized-distilled-water, indicating sorption at air-water interfaces or straining. Moreover, relatively smaller attachment was observed onto fine than medium quartz sand. The mass recovery of the 0.3 ?m microspheres in NaCl solution was shown to significantly decrease with increasing ionic strength. Both the experimental and theoretical collision efficiencies based on colloid interactions with solid-water interfaces, were increased with increasing ionic strength.

  15. Present status of solar distillation

    Microsoft Academic Search

    G. N. Tiwari; H. N. Singh; Rajesh Tripathi

    2003-01-01

    In this communication an attempt has been made to review, in brief, work on solar distillation, its present status in the world today and its future perspective. The review also includes water sources, water demand, availability of potable water and purification methods including the state of art and historical background. The classification of distillation units has been done on the

  16. Column Chromatography

    NSDL National Science Digital Library

    Julie Yu

    2007-01-01

    In this activity, learners separate the components of Gatorade using a home-made affinity column. In doing so, learners model the basic principle of affinity chromatography, a technique used to purify chemicals as well as bio-pharmaceuticals and petroleum products. This resource contains information about affinity chromatography and polarity.

  17. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  18. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  19. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  20. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  1. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  2. Minimum Energy Diagrams for Multieffect Distillation Arrangements

    E-print Network

    Skogestad, Sigurd

    Minimum Energy Diagrams for Multieffect Distillation Arrangements Hilde K. Engelien and Sigurd distillation arrangements for separating a ternary mixture have been considered. The focus is on a heat-integrated complex distillation configuration, called a multieffect prefractionator arrangement. The comparison

  3. TOTAL REFLUX OPERATION OF MULTIVESSEL BATCH DISTILLATION

    E-print Network

    Skogestad, Sigurd

    TOTAL REFLUX OPERATION OF MULTIVESSEL BATCH DISTILLATION BERND WITTGENS, RAJAB LITTO, EVA SØRENSEN in this paper provides a generalization of previously proposed batch distillation schemes. A simple feedback been built and the experiments verify the simulations. INTRODUCTION Although batch distillation

  4. Distilling entanglement from Fermions

    E-print Network

    M. Keyl

    2008-12-03

    Since Fermions are based on anti-commutation relations, their entanglement can not be studied in the usual way, such that the available theory has to be modified appropriately. Recent publications consider in particular the structure of separable and of maximally entangled states. In this talk we want to discuss local operations and entanglement distillation from bipartite, Fermionic systems. To this end we apply an algebraic point of view where algebras of local observables, rather than tensor product Hilbert spaces play the central role. We apply our scheme in particular to Fermionic Gaussian states where the whole discussion can be reduced to properties of the covariance matrix. Finally the results are demonstrated with free Fermions on an infinite, one-dimensional lattice.

  5. ETBE via catalytic distillation

    SciTech Connect

    Rock, K.L. [Catalytic Distillation Technologies, Houston, TX (United States)

    1993-12-31

    Recent political developments have altered the focus of refiners and blenders concerning oxygenates for reformulated gasoline. Ethanol and ethyl ethers (ETBE and TAEE) will receive preferential treatment under proposed legislation. Operations of existing and future ether plants are interested in flexibility to produce whatever ether has legislative or economic preference in the future. The use of DCTECH`s catalytic distillation technology offers advantages for alcohol flexibility, capital cost and operating cost. Additional features include high product purity, high isobutylene conversion and long catalyst life. Further cost reductions are available through the use of wet ethanol feed. The paper will address the technology features and benefits as well as economics. The results of recent commercial demonstration of the process will also be reviewed.

  6. Vapor compression distillation module

    NASA Technical Reports Server (NTRS)

    Nuccio, P. P.

    1975-01-01

    A Vapor Compression Distillation (VCD) module was developed and evaluated as part of a Space Station Prototype (SSP) environmental control and life support system. The VCD module includes the waste tankage, pumps, post-treatment cells, automatic controls and fault detection instrumentation. Development problems were encountered with two components: the liquid pumps, and the waste tank and quantity gauge. Peristaltic pumps were selected instead of gear pumps, and a sub-program of materials and design optimization was undertaken leading to a projected life greater than 10,000 hours of continuous operation. A bladder tank was designed and built to contain the waste liquids and deliver it to the processor. A detrimental pressure pattern imposed upon the bladder by a force-operated quantity gauge was corrected by rearranging the force application, and design goals were achieved. System testing has demonstrated that all performance goals have been fulfilled.

  7. Rigorous distillation dynamics simulations using a computer algebra

    Microsoft Academic Search

    Zakia Nasri; Housam Binous

    2009-01-01

    In the present paper, Mathematica1, the famous computer algebra, is used to perform steady- state and dynamic simulations of a multi-component distillation column. In order to describe the vaporliquid equilibrium (VLE) relationships and to compute the vapor- and liquid-phase enthalpies, the Soave? RedlichKwong equation of state (SRK EOS) is chosen. Rigorous modeling is performed where both mass and energy balance

  8. Characterization of down-flowing steam distillation system using step test analysis

    Microsoft Academic Search

    Zakiah Mohd Yusoff; Mohd Noor Nasriq Nordin; Mohd Hezri Fazalul Rahiman; Ramli Adnan; Mohd Nasir Taib

    2011-01-01

    This paper presents an application of step test in analysing the characterization and to observe the dynamics of new system which is down-flowing steam distillation system. Steam temperature data were collected in two condition: (a) without sample in the steam tray, (b) with sample in the steam tray-Cymbopogon Nardus (serai wangi ).The down-flowing steam distillation column developed in this work

  9. Hybrid Membrane-Cryogenic Distillation Air Separation Process for Oxygen Production

    Microsoft Academic Search

    Phillip C. Wankat; Kyle P. Kostroski

    2011-01-01

    A hybrid air separation process for oxygen production uses a membrane gas permeator with bypass to increase the oxygen concentration of the feed to 23.5% before the cryogenic distillation plant. A 23.5% limit on oxygen is required to avoid use of more expensive construction materials. By pre-concentrating the oxygen, the feed flowrate to the compressor, heat exchangers and distillation column

  10. Contexts for Column Addition and Subtraction

    ERIC Educational Resources Information Center

    Lopez Fernandez, Jorge M.; Velazquez Estrella, Aileen

    2011-01-01

    In this article, the authors discuss their approach to column addition and subtraction algorithms. Adapting an original idea of Paul Cobb and Erna Yackel's from "A Contextual Investigation of Three-Digit Addition and Subtraction" related to packing and unpacking candy in a candy factory, the authors provided an analogous context by designing…

  11. Enzyme activity maintenance in packed-bed reactors via continuous enzyme addition

    Microsoft Academic Search

    F. H. Verhoff; S. T. Schlager

    1981-01-01

    An operational scheme for using immobilized enzymes in packed-bed reactors that permits operation at a constant throughput rate and constant product quality is described. The scheme uses columns operated in series with continuous enzyme volume in the column system. Operation of columns in series is compared to operation where the flow rate is decreased to compensate for a loss of

  12. Optimal Control of Distillation Systems

    E-print Network

    Chatterjee, N.; Suchdeo, S. R.

    1984-01-01

    The optimum performance of a distillation system can be evaluated by examining the product purities, the product recoveries, and the system's capability to respond to small or large, expected or unexpected, plant disturbances. An optimal control...

  13. Leaf Pack Network

    NSDL National Science Digital Library

    The Leaf Pack Network (LPN) is a network of teachers and students investigating their local stream ecosystems by participating in the leaf pack experiment, which involves creating an artificial leaf pack (dry leaves in a mesh bag), immersing it in a stream for 3-4 weeks, and examining it for signs of aquatic insects as indicators of stream health. Participating classrooms share their data through the internet. This activity highlights the connection between streamside forests and the ecology of rivers and streams.

  14. Distillation process using microchannel technology

    SciTech Connect

    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.

  15. Isotropic non-locality cannot be distilled

    E-print Network

    Dejan D. Dukaric

    2011-09-20

    We investigate non-locality distillation protocols for isotropic correlations. These correlations are the hardest instances which respect to distillability and only partial results are known about their behaviour under non-locality distillation protocols. We completely resolve this issue by proving that non-locality distillation is impossible for all non-local isotropic correlations.

  16. Iterative packing for demand matching and sparse packing.

    SciTech Connect

    Parekh, Ojas

    2010-11-01

    The main result we will present is a 2k-approximation algorithm for the following 'k-hypergraph demand matching' problem: given a set system with sets of size <=k, where sets have profits & demands and vertices have capacities, find a max-profit subsystem whose demands do not exceed the capacities. The main tool is an iterative way to explicitly build a decomposition of the fractional optimum as 2k times a convex combination of integral solutions. If time permits we'll also show how the approach can be extended to a 3-approximation for 2-column sparse packing. The second result is tight w.r.t the integrality gap, and the first is near-tight as a gap lower bound of 2(k-1+1/k) is known.

  17. Quantum universality by state distillation

    E-print Network

    Ben W. Reichardt

    2009-07-13

    Quantum universality can be achieved using classically controlled stabilizer operations and repeated preparation of certain ancilla states. Which ancilla states suffice for universality? This "magic states distillation" question is closely related to quantum fault tolerance. Lower bounds on the noise tolerable on the ancilla help give lower bounds on the tolerable noise rate threshold for fault-tolerant computation. Upper bounds show the limits of threshold upper-bound arguments based on the Gottesman-Knill theorem. We extend the range of single-qubit mixed states that are known to give universality, by using a simple parity-checking operation. For applications to proving threshold lower bounds, certain practical stability characteristics are often required, and we also show a stable distillation procedure. No distillation upper bounds are known beyond those given by the Gottesman-Knill theorem. One might ask whether distillation upper bounds reduce to upper bounds for single-qubit ancilla states. For multi-qubit pure states and previously considered two-qubit ancilla states, the answer is yes. However, we exhibit two-qubit mixed states that are not mixtures of stabilizer states, but for which every postselected stabilizer reduction from two qubits to one outputs a mixture of stabilizer states. Distilling such states would require true multi-qubit state distillation methods.

  18. Distillation and Air Stripping Designs for the Lunar Surface

    NASA Technical Reports Server (NTRS)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Air stripping and distillation are two different gravity-based methods, which may be applied to the purification of wastewater on the lunar base. These gravity-based solutions to water processing are robust physical separation techniques, which may be advantageous to many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation models and air stripping models. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for the for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Distillation processes are modeled separately and in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams. Components of the wastewater streams are ranked by Henry s Law Constant and the suitability of air stripping in the purification of wastewater in terms of component removal is evaluated. Scaling factors for distillation and air stripping columns are presented to account for the difference in the lunar gravitation environment. Commercially available distillation and air stripping units which are considered suitable for Exploration Life Support are presented. The advantages to the various designs are summarized with respect to water purity levels, power consumption, and processing rates.

  19. Non-planar microfabricated gas chromatography column

    DOEpatents

    Lewis, Patrick R. (Albuquerque, NM); Wheeler, David R. (Albuquerque, NM)

    2007-09-25

    A non-planar microfabricated gas chromatography column comprises a planar substrate having a plurality of through holes, a top lid and a bottom lid bonded to opposite surfaces of the planar substrate, and inlet and outlet ports for injection of a sample gas and elution of separated analytes. A plurality of such planar substrates can be aligned and stacked to provide a longer column length having a small footprint. Furthermore, two or more separate channels can enable multi-channel or multi-dimensional gas chromatography. The through holes preferably have a circular cross section and can be coated with a stationary phase material or packed with a porous packing material. Importantly, uniform stationary phase coatings can be obtained and band broadening can be minimized with the circular channels. A heating or cooling element can be disposed on at least one of the lids to enable temperature programming of the column.

  20. Search Strategies for Rectangle Packing

    Microsoft Academic Search

    Helmut Simonis; Barry O’Sullivan

    2008-01-01

    Abstract. Rectangle (square) packing problems,involve packing all squares with sizes 1 × 1 to n × n into the minimum area enclosing rectangle (respectively, square). Rectangle packing is a variant of an important problem,in a variety of real-world settings. For example, in electronic design automation, the packing of blocks into a circuit layout is essentially a rectangle packing problem. Rectangle

  1. Random packings of frictionless particles

    Microsoft Academic Search

    Corey O'Hern; Stephen Langer; Andrea Liu; Sidney Nagel

    2002-01-01

    We conduct numerical simulations of random packings of particles interacting via repulsive, finite-range potentials to study a special point at T=0. This point marks the onset of jamming with increasing packing fraction. Static granular packings must necessarily lie near this point because the particles are hard and it is difficult to compress packings to higher packing fraction. We find that

  2. Random Packings of Frictionless Particles

    Microsoft Academic Search

    Corey S. O'Hern; Stephen A. Langer; Andrea J. Liu; Sidney R. Nagel

    2002-01-01

    We conduct numerical simulations of random packings of frictionless particles at T = 0. The packing fraction where the pressure becomes nonzero is the same as the jamming threshold, where the static shear modulus becomes nonzero. The distribution of threshold packing fractions narrows, and its peak approaches random close packing as the system size increases. For packing fractions within the

  3. Flat Pack Toy Design

    ERIC Educational Resources Information Center

    Hutcheson, Brian

    2007-01-01

    In this article, the author introduces the concept of flat pack toys. Flat pack toys are designed using a template on a single sheet of letter-sized card stock paper. Before being cut out and built into a three-dimensional toy, they are scanned into the computer and uploaded to a website. With the template accessible from the website, anyone with…

  4. Comparison of advanced distillation control methods. Third annual report

    SciTech Connect

    Riggs, J.B.

    1997-07-01

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls, feedforward from a feed composition analyzer, and decouplers. Auto Tune Variation (ATV) identification with on-line detuning for setpoint changes was used for tuning the diagonal proportional integral (PI) composition controls. In addition, robustness tests were conducted by inducting reboiler duty upsets. For single composition control, the (L, V) configuration was found to be best. For dual composition control, the optimum configuration changes from one column to another. Moreover, the use of analysis tools, such as RGA, appears to be of little value in identifying the optimum configuration for dual composition control. Using feedforward from a feed composition analyzer and using decouplers are shown to offer significant advantages for certain specific cases.

  5. Chromatographic classification of commercially available reverse-phase HPLC columns

    Microsoft Academic Search

    E. Cruz; M. R. Euerby; C. M. Johnson; C. A. Hackett

    1997-01-01

    Summary  The ever-increasing number of commercially available reversed phases with which the analyst is confronted can cause problems\\u000a in column selection. These and the non-standard test procedures used by the column manufacturers and packing companies cause\\u000a further confusion. In order to independently compare and contrast a range of well established C18 stationary phases, we have\\u000a performed a modified column characterization approach,

  6. Intermediate Vapor Expansion Distillation and Nested Enrichment Cascade Distillation

    E-print Network

    Erickson, D. C.

    ----------------, .. 134 ESL-IE-86-06-25 Proceedings from the Eighth Annual Industrial Energy Technology Conference, Houston, TX, June 17-19, 1986 ~ A. Cascades 1. Cryogenic Distillation Since most cryogenic distillations, are inherently driven by work (Le... kPa 95.6 K AIR 117 kPa --. 138kPa NESTED CASCADE AIR AIR COMPRESSOR CONVENTIONAL Conv'l CASCADE NEC Pre kPa ssure asia Energy 579 84 1.0 441 64 .844 Figure 4. Energy Effect of Nested Cascade Distilla tion on Cryogenic Air...

  7. Antioxidant activity of phytochemicals from dried distillers grain oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A distillate was obtained by molecular distillation of oil extracted from distiller’s dried grains (DDG). The dried distiller’s grains distillate (DDGD) contained phytosterols, steryl ferulates, tocopherols, tocotrienols, and carotenoids. DDGD was tested for its impact on the oxidative stability in...

  8. Antioxidant Activity of Phytochemicals from Dried Distillers Grain Oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A distillate was obtained by molecular distillation of oil extracted from distiller’s dried grains (DDG). The dried distiller’s grains distillate (DDGD) contained phytosterols, steryl ferulates, tocopherols, tocotrienols, and carotenoids. DDGD was tested for its impact on the oxidative stability i...

  9. Radiotracer Imaging of Sediment Columns

    NASA Astrophysics Data System (ADS)

    Moses, W. W.; O'Neil, J. P.; Boutchko, R.; Nico, P. S.; Druhan, J. L.; Vandehey, N. T.

    2010-12-01

    Nuclear medical PET and SPECT cameras routinely image radioactivity concentration of gamma ray emitting isotopes (PET - 511 keV; SPECT - 75-300 keV). We have used nuclear medical imaging technology to study contaminant transport in sediment columns. Specifically, we use Tc-99m (T1/2 = 6 h, E? = 140 keV) and a SPECT camera to image the bacteria mediated reduction of pertechnetate, [Tc(VII)O4]- + Fe(II) ? Tc(IV)O2 + Fe(III). A 45 mL bolus of Tc-99m (32 mCi) labeled sodium pertechnetate was infused into a column (35cm x 10cm Ø) containing uranium-contaminated subsurface sediment from the Rifle, CO site. A flow rate of 1.25 ml/min of artificial groundwater was maintained in the column. Using a GE Millennium VG camera, we imaged the column for 12 hours, acquiring 44 frames. As the microbes in the sediment were inactive, we expected most of the iron to be Fe(III). The images were consistent with this hypothesis, and the Tc-99m pertechnetate acted like a conservative tracer. Virtually no binding of the Tc-99m was observed, and while the bolus of activity propagated fairly uniformly through the column, some inhomogeneity attributed to sediment packing was observed. We expect that after augmentation by acetate, the bacteria will metabolically reduce Fe(III) to Fe(II), leading to significant Tc-99m binding. Imaging sediment columns using nuclear medicine techniques has many attractive features. Trace quantities of the radiolabeled compounds are used (micro- to nano- molar) and the half-lives of many of these tracers are short (<1 day). This allows multiple measurements to be made on the same column and thus the sediment biology to be monitored non-invasively over time (i.e. after an augmentation has been introduced) and minimizes long-lived radioactive waste. Different parameters can be measured, depending on the tracer type and delivery. A constant infusion of a conservative tracer, such as the positron emitter Br-76 (T1/2= 16.2 hr), measures the exclusion fraction (as a function of position in the column), while a bolus maps the flow velocity as a function of position. A tracer that interacts chemically with the contents of the column (e.g., [99m-Tc(VII)O4]- reduced to 99m-TcO2 by Fe(II) ) yields a map of the chemical environment (e.g., the distribution of Fe(II)). Image of Tc-99m distribution in a column containing Rifle sediment at four times.

  10. Optimal protocols for nonlocality distillation

    SciTech Connect

    Hoeyer, Peter; Rashid, Jibran [Department of Computer Science, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, 2N 1N4 (Canada)

    2010-10-15

    Forster et al. recently showed that weak nonlocality can be amplified by giving the first protocol that distills a class of nonlocal boxes (NLBs) [Phys. Rev. Lett. 102, 120401 (2009)] We first show that their protocol is optimal among all nonadaptive protocols. We next consider adaptive protocols. We show that the depth-2 protocol of Allcock et al. [Phys. Rev. A 80, 062107 (2009)] performs better than previously known adaptive depth-2 protocols for all symmetric NLBs. We present a depth-3 protocol that extends the known region of distillable NLBs. We give examples of NLBs for which each of the Forster et al., the Allcock et al., and our protocols perform best. The understanding we develop is that there is no single optimal protocol for NLB distillation. The choice of which protocol to use depends on the noise parameters for the NLB.

  11. Compartmental modeling of high purity air separation columns

    Microsoft Academic Search

    Shoujun Bian; Suabtragool Khowinij; Michael A. Henson; Paul Belanger; Lawrence Megan

    2005-01-01

    High purity distillation columns are critical unit operations in cryogenic air separation plants. The development of nonlinear control technology is motivated by the need to frequently change production rates in response to time varying utility costs. Detailed column models based on stage-by-stage balance equations are too complex to be incorporated directly into optimization-based strategies such as nonlinear model predictive control.

  12. Compartmental modeling of high purity air separation columns

    Microsoft Academic Search

    Shoujun Biana; Suabtragool Khowinij; Michael A. Henson; Paul Belanger; Lawrence Megan

    High purity distillation columns are critical unit operations in cryogenic air separation plants. The development of nonlinear control technology is motivated by the need to frequently change production rates in response to time varying utility costs. Detailed column models based on stage-by-stage balance equations are too complex to be incorporated directly into optimization-based strategies such as nonlinear model predictive control.

  13. Graphitic packing removal tool

    DOEpatents

    Meyers, Kurt Edward (Avella, PA); Kolsun, George J. (Pittsburgh, PA)

    1997-01-01

    Graphitic packing removal tools for removal of the seal rings in one piece. he packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.

  14. Joule heating in packed capillaries used in capillary electrochromatography.

    PubMed

    Rathore, Anurag S; Reynolds, Kimberly J; Colón, Luis A

    2002-09-01

    Effective heat dissipation is critical for reproducible and efficient separations in electrically driven separation systems. Flow rate, retention kinetics, and analyte diffusion rates are some of the characteristics that are affected by variation in the temperature of the mobile phase inside the column. In this study, we examine the issue of Joule heating in packed capillary columns used in capillary electrochromatography (CEC). As almost all commonly used CEC packings are poor thermal conductors, it is assumed that the packing particles do not conduct heat and heat transfer is solely through the mobile phase flowing through the system. The electrical conductivity of various mobile phases was measured at different temperatures by a conductivity meter and the temperature coefficient for each mobile phase was calculated. This was followed by measurement of the electrical current at several applied voltages to calculate the conductivity of the solution within the column as a function of the applied voltage. An overall increase in the conductivity is attributed to Joule heating within the column, while a constant conductivity means good heat dissipation. A plot of conductivity versus applied voltage was used as the indicator of poor heat dissipation. Using theories that have been proposed earlier for modeling of Joule heating effects in capillary electrophoresis (CE), we estimated the temperature within CEC columns. Under mobile and stationary phase conditions typically used in CEC, heat dissipation was found to be not always efficient. Elevated temperatures within the columns in excess of 23 degrees C above ambient temperature were calculated for packed columns, and about 35 degrees C for an open column, under a given set of conditions. The results agree with recently published experimental findings with nuclear magnetic resonance (NMR) thermometry, and Raman spectroscopic measurements. PMID:12207300

  15. Solar distillation of sea water

    SciTech Connect

    Subramanyam, S. (Kakatiya Institute of Technology and Science, Warangal (India))

    1989-01-01

    Indian coastal and fishing villages suffer from scarcity of potable water. Solar distillation could provide a solution to this problem by adopting the following criteria: (1) Integration of distillation and storage systems with the house design. (2) Public supply of sea water and a public drain pipe system to periodically drain away the concentrated brine. (3) Harvest and store rain water to tide over cloudy rainy periods. In India there has been a thrust towards centralized non-conventional energy systems. Decentralized non-conventional energy devices and centralized service support units may offer a better solution. 1 fig.

  16. Entanglement distillation using particle statistics

    E-print Network

    H. L. Huang; L. H. Cheng; X. X. Yi

    2005-10-25

    We extend the idea of entanglement concentration for pure states(Phys. Rev. Lett. {\\bf 88}, 187903) to the case of mixed states. The scheme works only with particle statistics and local operations, without the need of any other interactions. We show that the maximally entangled state can be distilled out when the initial state is pure, otherwise the entanglement of the final state is less than one. The distillation efficiency is a product of the diagonal elements of the initial state, it takes the maximum 50%, the same as the case for pure states.

  17. Extended testing of compression distillation.

    NASA Technical Reports Server (NTRS)

    Bambenek, R. A.; Nuccio, P. P.

    1972-01-01

    During the past eight years, the NASA Manned Spacecraft Center has supported the development of an integrated water and waste management system which includes the compression distillation process for recovering useable water from urine, urinal flush water, humidity condensate, commode flush water, and concentrated wash water. This paper describes the design of the compression distillation unit, developed for this system, and the testing performed to demonstrate its reliability and performance. In addition, this paper summarizes the work performed on pretreatment and post-treatment processes, to assure the recovery of sterile potable water from urine and treated urinal flush water.

  18. Bounds for nonlocality distillation protocols

    SciTech Connect

    Forster, Manuel [Computer Science Department, ETH Zuerich, CH-8092 Zuerich (Switzerland)

    2011-06-15

    Nonlocality can be quantified by the violation of a Bell inequality. Since this violation may be amplified by local operations, an alternative measure has been proposed--distillable nonlocality. The alternative measure is difficult to calculate exactly due to the double exponential growth of the parameter space. In this paper, we give a way to bound the distillable nonlocality of a resource by the solutions to a related optimization problem. Our upper bounds are exponentially easier to compute than the exact value and are shown to be meaningful in general and tight in some cases.

  19. Distilling entanglement from arbitrary resources

    E-print Network

    Francesco Buscemi; Nilanjana Datta

    2010-10-15

    We obtain the general formula for the optimal rate at which singlets can be distilled from any given noisy and arbitrarily correlated entanglement resource, by means of local operations and classical communication (LOCC). Our formula, obtained by employing the quantum information spectrum method, reduces to that derived by Devetak and Winter, in the special case of an i.i.d. resource. The proofs rely on a one-shot version of the so-called "hashing bound," which in turn provides bounds on the one-shot distillable entanglement under general LOCC.

  20. Packing Peanut Properties

    NSDL National Science Digital Library

    Dori Hall

    2002-02-02

    Students work with various types of packing peanuts to investigate states of matter and chemical and physical changes. One of the activities involves making slime. The activities can easily be modified for students with learning disabilities.

  1. Packing paths in digraphs

    E-print Network

    Richard C. Brewster; Pavol Hell; Sarah H. Pantel; Romeo Rizzi; Anders Yeo

    f ~P1g, or f ~P1; ~P2g, the G-packing problem is NP-complete. When G = f ~P1g, the G-packing problem is simply the matching problem. We treat in detail the one remaining case, G = f ~P1; ~P2g. We give in this case a polynomial algorithm for the packing problem. We also give the following positive results: a Berge type augmenting configuration theorem, a min-max characterization, and a reduction to bipartite matching. These results apply also to packings by the family G consisting of all directed paths and cycles. We also explore weighted variants of the problem and include a polyhedral analysis.

  2. Nasal packing and stenting

    PubMed Central

    Weber, Rainer K.

    2011-01-01

    Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue. PMID:22073095

  3. Fully Dynamic Bin Packing

    NASA Astrophysics Data System (ADS)

    Ivkovi?, Zoran; Lloyd, Errol L.

    Classic bin packing seeks to pack a given set of items of possibly varying sizes into a minimum number of identical sized bins. A number of approximation algorithms have been proposed for this NP-hard problem for both the on-line and off-line cases. In this chapter we discuss fully dynamic bin packing, where items may arrive (Insert) and depart (Delete) dynamically. In accordance with standard practice for fully dynamic algorithms, it is assumed that the packing may be arbitrarily rearranged to accommodate arriving and departing items. The goal is to maintain an approximately optimal solution of provably high quality in a total amount of time comparable to that used by an off-line algorithm delivering a solution of the same quality.

  4. Control strategies for reactive batch distillation Eva Swensen and Sigurd Skogestad"

    E-print Network

    Skogestad, Sigurd

    the reactor temperature (one-point bottom control) is difficult since the set-point has to be specified below reactor temperature and distillate composition (two-point control) is also found to be difficult due to large interactions in the column. As with one-point bottom control, the reactor temperature has

  5. Distillation of hydrogen isotopes for polarized HD target

    E-print Network

    Ohta, T; Didelez, J -P; Fujiwara, M; Fukuda, K; Kohri, H; Kunimatsu, T; Morisaki, C; Ono, S; Rouill', G; Tanaka, M; Ueda, K; Uraki, M; Utsuro, M; Wang, S Y; Yosoi, M

    2011-01-01

    We have developed a cryogenic distillation system to purify Hydrogen-Deuteride (HD) gas for a polarized HD target in LEPS experiments at SPring-8. A small amount of ortho-H$_2$ ($\\sim$0.01%) in the HD gas plays an important role in efficiently polarizing the HD target. Since there are 1$\\sim$5% impurities of H$_2$ and D$_2$ in commercially available HD gases, it is inevitable that the HD gas is purified up to $\\sim$99.99%. The distillation system has a cryogenic pot (17$\\sim$21 K) containing many small stainless steel cells called Heli-pack. Commercial HD gas with an amount of 5.2 mol is fed into the pot. We carried out three distillation runs 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 by using a gas analyzer system combining a quadrupole mass spectrometer with a gas chromatograph. The HD gas of 1 mol with a purity better than 99.99% has been successfully obtained. The effective NTS (Number of Theoretical Stages), which is...

  6. Sphere packings III

    Microsoft Academic Search

    Thomas C. Hales

    1998-01-01

    This is the fifth in a series of papers giving a proof of the Kepler conjecture, which asserts that the density of a packing of congruent spheres in three dimensions is never greater than $\\\\pi\\/\\\\sqrt{18}\\\\approx 0.74048...$. This is the oldest problem in discrete geometry and is an important part of Hilbert's 18th problem. An example of a packing achieving this

  7. Bulk stress distributions in the pore space of sphere-packed beds under Darcy flow conditions

    NASA Astrophysics Data System (ADS)

    Pham, Ngoc H.; Voronov, Roman S.; Tummala, Naga Rajesh; Papavassiliou, Dimitrios V.

    2014-03-01

    In this paper, bulk stress distributions in the pore space of columns packed with spheres are numerically computed with lattice Boltzmann simulations. Three different ideally packed and one randomly packed configuration of the columns are considered under Darcy flow conditions. The stress distributions change when the packing type changes. In the Darcy regime, the normalized stress distribution for a particular packing type is independent of the pressure difference that drives the flow and presents a common pattern. The three parameter (3P) log-normal distribution is found to describe the stress distributions in the randomly packed beds within statistical accuracy. In addition, the 3P log-normal distribution is still valid when highly porous scaffold geometries rather than sphere beds are examined. It is also shown that the 3P log-normal distribution can describe the bulk stress distribution in consolidated reservoir rocks like Berea sandstone.

  8. Bulk stress distributions in the pore space of sphere-packed beds under Darcy flow conditions.

    PubMed

    Pham, Ngoc H; Voronov, Roman S; Tummala, Naga Rajesh; Papavassiliou, Dimitrios V

    2014-03-01

    In this paper, bulk stress distributions in the pore space of columns packed with spheres are numerically computed with lattice Boltzmann simulations. Three different ideally packed and one randomly packed configuration of the columns are considered under Darcy flow conditions. The stress distributions change when the packing type changes. In the Darcy regime, the normalized stress distribution for a particular packing type is independent of the pressure difference that drives the flow and presents a common pattern. The three parameter (3P) log-normal distribution is found to describe the stress distributions in the randomly packed beds within statistical accuracy. In addition, the 3P log-normal distribution is still valid when highly porous scaffold geometries rather than sphere beds are examined. It is also shown that the 3P log-normal distribution can describe the bulk stress distribution in consolidated reservoir rocks like Berea sandstone. PMID:24730946

  9. Distillation: Present Status and Future Directions

    E-print Network

    Fair, J. R.; Humphrey, J. L.

    1984-01-01

    Distillation will undoubtedly continue to be the most-used method for separating liquid mixtures, at any scale of operation. For this reason, and also because of its recognized energy intensiveness, distillation commands continued scrutiny...

  10. Yeast Genomic DNA Prep Sterile distilled water

    E-print Network

    Auble, David

    Auble Lab Yeast Genomic DNA Prep Reagents: Sterile distilled water -mercaptoethanol Sorbitol Buffer conical tube at 3,000 rpms for 5 minutes. 3. Resuspend in 10 ml of sterile distilled (SD) water, then spin

  11. Plant transpiration distillation of water

    SciTech Connect

    Virostko, M.K.; Spielberg, J.I.

    1986-01-01

    A project using solar energy and the transpiration of plants for the distillation of water is described. Along with determining which of three plants thrived best growing in a still, the experiment also revealed that the still functioned nearly as well in inclement weather as in fair weather.

  12. Properties of Distillers Grains Composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in renewable biofuel sources has intensified in recent years, leading to greatly increased production of ethanol and its primary coproduct, Distillers Dried Grain with Solubles (DDGS). Consequently, the development of new outlets for DDGS has become crucial to maintaining the economic viab...

  13. OPPORTUNITIES FOR UTILIZING DISTILLERS GRAINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fuel ethanol industry is currently experiencing unprecedented growth. In conjunction with this expansion, the quantity of distillers grains produced over time has grown in parallel. This industry has continually evolved, and technological innovations and process changes have been implemented tha...

  14. Purifying Aluminum by Vacuum Distillation

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1985-01-01

    Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

  15. Entanglement preservation by continuous distillation

    SciTech Connect

    Mundarain, D. [Departmento de Fisica, Seccion de Fenomenos Opticos, Universidad Simon Bolivar, Apartado Postal 89000, Caracas 1080A (Venezuela, Bolivarian Republic of); Orszag, M. [Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile)

    2009-05-15

    We study the two-qubit entanglement preservation for a system in the presence of independent thermal baths. We use a combination of filtering operations and distillation protocols as a series of frequent measurements on the system. It is shown that a small fraction of the total amount of available copies of the system preserves or even improves its initial entanglement during the evolution.

  16. Entanglement distillation by extendible maps

    E-print Network

    Lukasz Pankowski; Fernando G. S. L. Brandao; Michal Horodecki; Graeme Smith

    2013-08-25

    It is known that from entangled states that have positive partial transpose it is not possible to distill maximally entangled states by local operations and classical communication (LOCC). A long-standing open question is whether maximally entangled states can be distilled from every state with a non-positive partial transpose. In this paper we study a possible approach to the question consisting of enlarging the class of operations allowed. Namely, instead of LOCC operations we consider k-extendible operations, defined as maps whose Choi-Jamiolkowski state is k-extendible. We find that this class is unexpectedly powerful - e.g. it is capable of distilling EPR pairs even from product states. We also perform numerical studies of distillation of Werner states by those maps, which show that if we raise the extension index k simultaneously with the number of copies of the state, then the class of k-extendible operations is not that powerful anymore and provide a better approximation to the set of LOCC operations.

  17. Corrosion inhibition for distillation apparatus

    DOEpatents

    Baumert, Kenneth L. (Emmaus, PA); Sagues, Alberto A. (Lexington, KY); Davis, Burtron H. (Georgetown, KY); Schweighardt, Frank K. (Upper Macungie, PA)

    1985-01-01

    Tower material corrosion in an atmospheric or sub-atmospheric distillation tower in a coal liquefaction process is reduced or eliminated by subjecting chloride-containing tray contents to an appropriate ion-exchange resin to remove chloride from such tray contents materials.

  18. Predictive control of distillation processes

    Microsoft Academic Search

    1986-01-01

    In this study, predictive control is applied to two fundamental control problems found in most distillation processes: averaging level control and product quality control. An optimal averaging level control problem is defined and solved for a surge tank system. Two averaging level controllers, the ramp controller and the optimal predictive controller, are developed utilizing the optimal control policy. The ramp

  19. Biodegradation of chlorinated aliphatic hydrocarbon mixtures in a single-pass packed-bed reactor

    Microsoft Academic Search

    L. W. Lackey; T. J. Phelps; P. R. Bienkowski; D. C. White

    1993-01-01

    Aliphatic chlorinated compounds, such as trichloroethylene (TCE) and tetrachloroethylene (PCE), are major contaminants of\\u000a ground water. A single-pass packed-bed bioreactor was utilized to study the biodegradation of organic waste mixtures consisting\\u000a of PCE, TCE, and other short-chain chlorinated organics. The bioreactor consisted of two 1960-mL glass columns joined in a\\u000a series. One column was packed with sand containing a microbial

  20. 27 CFR 19.322 - Distillates containing extraneous substances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Distillates containing aldehydes may be removed, without payment of tax, to an adjacent bonded wine cellar for use therein for fermentation of wine to be used as distilling material at the distilled spirits plant from which the distillates were removed....

  1. DNA Spin Columns Regular Spin Columns

    E-print Network

    Aris, John P.

    or bubbles. 1. Remove tip of Bio-Rad column. Place column in 13 X 100 mm glass tube in rack. Fill column tube in 50 ml plastic centrifuge tube. Spin 10 minutes at 1000 rpm (~250 g) in IEC centrifuge. After centrifuge with swing-out rotor. Plastic Syringes Prepare syringes as follows. Cut circles of GF/C (glass

  2. Experimental entanglement distillation of mesoscopic quantum states

    E-print Network

    Loss, Daniel

    LETTERS Experimental entanglement distillation of mesoscopic quantum states RUIFANG DONG1 , MIKAEL, entanglement distillation, a process of extracting a small set of highly entangled states from a large set of less entangled states, can be used4­14 . Here we report on the distillation of deterministically

  3. TOTAL REFLUX OPERATION OF MULTIVESSEL BATCH DISTILLATION

    E-print Network

    Skogestad, Sigurd

    TOTAL REFLUX OPERATION OF MULTIVESSEL BATCH DISTILLATION BERND WITTGENS, RAJAB LITTO, EVA S RENSEN a generalization of previously proposed batch distillation schemes. A simple feedback control strategy for total re verify the simulations. INTRODUCTION Although batch distillation generally is less energy e cient than

  4. 21 CFR 184.1848 - Starter distillate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Starter distillate (butter starter distillate) is a steam distillate of the culture of any or all of the following species of bacteria grown on a medium consisting of skim milk usually fortified with about 0.1 percent citric acid: Streptococcus...

  5. 21 CFR 184.1848 - Starter distillate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Starter distillate (butter starter distillate) is a steam distillate of the culture of any or all of the following species of bacteria grown on a medium consisting of skim milk usually fortified with about 0.1 percent citric acid: Streptococcus...

  6. EXPERIMENT 9 GAS CHROMATOGRAPHY QUALITATIVE ANALYSIS USING PACKED

    E-print Network

    Nazarenko, Alexander

    EXPERIMENT 9 GAS CHROMATOGRAPHY QUALITATIVE ANALYSIS USING PACKED COLUMN The purpose become familiar with the use of a temperature programmable gas chromatograph. See also the gas on the gas chromatograph so that the tr values may be obtained. Instrument Start Up. Turn on the gas

  7. Simulated distillation of high-boiling petroleum fractions by capillary supercritical fluid chromatography and vacuum thermal gravimetric analysis

    Microsoft Academic Search

    Herbert E. Schwartz; Robert G. Brownlee; Mieczyslaw M. Boduszynski; Fu. Su

    1987-01-01

    Capillary supercritical fluid chromatography (SFC) and vacuum thermal gravimetric analysis (VTGA) were utilized for simulated distillation (SIMDIS) of high-boiling petroleum fractions obtained by short-path vacuum distillation. The SFC method covers the approximate boiling range of 250-1400°F. Under the present conditions, even 42% of a nondistillable, nondeasphalted residue was recovered from the column at a calculated 1426°F atmospheric equivalent boiling point.

  8. Distillation of hydrogen isotopes for polarized HD target

    E-print Network

    T. Ohta; S. Bouchigny; J. -P. Didelez; M. Fujiwara; K. Fukuda; H. Kohri; T. Kunimatsu; C. Morisaki; S. Ono; G. Rouill'; M. Tanaka; K. Ueda; M. Uraki; M. Utsuro; S. Y. Wang; M. Yosoi

    2011-12-12

    We have developed a cryogenic distillation system to purify Hydrogen-Deuteride (HD) gas for a polarized HD target in LEPS experiments at SPring-8. A small amount of ortho-H$_2$ ($\\sim$0.01%) in the HD gas plays an important role in efficiently polarizing the HD target. Since there are 1$\\sim$5% impurities of H$_2$ and D$_2$ in commercially available HD gases, it is inevitable that the HD gas is purified up to $\\sim$99.99%. The distillation system has a cryogenic pot (17$\\sim$21 K) containing many small stainless steel cells called Heli-pack. Commercial HD gas with an amount of 5.2 mol is fed into the pot. We carried out three distillation runs by changing temperatures (17.5 K and 20.5 K) and gas extraction speeds (1.3 ml/min and 5.2 ml/min). The extracted gas was analyzed by using a gas analyzer system combining a quadrupole mass spectrometer with a gas chromatograph. The HD gas of 1 mol with a purity better than 99.99% has been successfully obtained. The effective NTS (Number of Theoretical Stages), which is an indicator of the distillator performances, is obtained as 37.2$\\pm$0.6. This value is in reasonable agreement with a designed value of 37.9. The HD target is expected to be efficiently polarized under a well-controlled condition by doping an optimal amount of ortho-H$_2$ to the purified HD gas.

  9. Random Packings of Frictionless Particles

    Microsoft Academic Search

    Corey S. O'Hern; Stephen A. Langer; Andrea J. Liu; R. Nagel

    2002-01-01

    We study random packings of frictionless particles at T=0.\\u000a The packing fraction where the pressure becomes nonzero is the same as the\\u000ajamming threshold, where the static shear modulus becomes nonzero. The\\u000adistribution of threshold packing fractions narrows and its peak approaches\\u000arandom close-packing as the system size increases. For packing fractions within\\u000athe peak, there is no self-averaging, leading

  10. Cascade Distillation Subsystem Development: Progress Toward a Distillation Comparison Test

    NASA Technical Reports Server (NTRS)

    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.

  11. Continuous synthesis of lauroyl or oleoyl erythritol by a packed-bed reactor with an immobilized lipase

    Microsoft Academic Search

    Junkui Piao; Takashi Kobayashi; Shuji Adachi; Kazuhiro Nakanishi; Ryuichi Matsuno

    2004-01-01

    A system is proposed for the continuous synthesis of an acyl erythritol through the immobilised-lipase-catalysed condensation of the corresponding fatty acid and erythritol in acetone. A fatty acid dissolved in acetone was fed to a column packed with erythritol powders, and erythritol was dissolved in the column at a saturated concentration. The effluent from the column was introduced to a

  12. Computerized valve packing program

    SciTech Connect

    Taraszki, R. [Argo Packing Co., Aurora, IL (United States)

    1996-11-01

    The purpose of this paper is to present the advantages of a computerized valve packing program and demonstrate Valveman{trademark}, a windows based, completely automated valve packing program. With deregulation of the power industry, it is evident to be more competitive, utilities are decreasing maintenance staffs. This challenges the personnel to be more productive. One area that is usually duplicated by various groups on a site is valve packing. So it is evident that a way of simplifying this process is very beneficial, not only from an efficiency stand point but also to a greater consistency and higher quality level. By establishing a consistency, it is easier to change personnel with a minimum learning curve. Also, the administration can get a complete picture of each job for better evaluation or to measure performance.

  13. Distillate Market Model documentation report

    SciTech Connect

    Not Available

    1993-12-01

    The purpose of this report is to define the objectives of the Distillate Market Model (DMM), describe its basic approach, and to provide details on model functions. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with EIA`s legal obligation to provide adequate documentation in support of its models. The DMM performs a short-term (6- to 9-month) forecast of demand and retail price for distillate fuel oil in the national US market; it also calculates the end-of-month stock level during the term of the forecast. The model is used to analyze certain market behavior assumptions or shocks and to determine the effect on retail market price, demand, and stock level.

  14. Selective hydrocracking of middle distillates

    SciTech Connect

    Konoval'chikov, L.D.; Konoval'chikov, O.D.; Kruglikov, V.Y.; Nefedov, B.K.

    1984-09-01

    This article presents selective hydrocracking test results on the SGK-1 catalyst with various distillate feedstocks (both straight-run and stocks from secondary processes). The tests were performed in single-pass laboratory flow units (catalyst charge 20 cm/sup 3/) and in pilot-plant units (catalyst charge 100-500 cm/sup 3/). Data are presented on the composition and properties of the liquid product obtained by selective hydrogenation, in the pilot unit, of a straight-run hydrotreated kerosine cut from Romashkino-type crude. The results indicate that the SGK-1 catalyst, which was developed on the basis of the USSR high-silica zeolites TsVK and TsVM, has a high and stable catalytic activity and a high selectivity in cracking the n-alkanes present in middle distillates.

  15. Experimental Distillation of Quantum Nonlocality

    NASA Astrophysics Data System (ADS)

    Zu, C.; Deng, D.-L.; Hou, P.-Y.; Chang, X.-Y.; Wang, F.; Duan, L.-M.

    2013-08-01

    We report the first experimental demonstration of distillation of quantum nonlocality, confirming the recent theoretical protocol [Phys. Rev. Lett. 102, 120401 (2009)]. Quantum nonlocality is described by a correlation box with binary inputs and outputs, and the nonlocal boxes are realized through appropriate measurements on polarization entangled photon pairs. We demonstrate that nonlocality is amplified by connecting two nonlocal boxes into a composite one through local operations and four-photon measurements.

  16. Selective hydrocracking of middle distillates

    Microsoft Academic Search

    L. D. Konovalchikov; O. D. Konovalchikov; V. Y. Kruglikov; B. K. Nefedov

    1984-01-01

    This article presents selective hydrocracking test results on the SGK-1 catalyst with various distillate feedstocks (both straight-run and stocks from secondary processes). The tests were performed in single-pass laboratory flow units (catalyst charge 20 cm³) and in pilot-plant units (catalyst charge 100-500 cm³). Data are presented on the composition and properties of the liquid product obtained by selective hydrogenation, in

  17. Hydrodynamic and mass transfer characteristic of a novel grid-structured plastic packing

    NASA Astrophysics Data System (ADS)

    Lehner, Markus; Hoffmann, Karin; Geipel, Werner

    2011-08-01

    The hydraulic and mass transfer characteristic of a novel grid-structured plastic packing is presented. The geometry of this structured packings differ substantially from conventional corrugated structured packings resulting in an open structure which enables a free exchange of vapour and liquid also in horizontal direction. The hydraulic performance has been measured by air-water experiments in a 440 mm diameter column, the mass transfer characteristic has been determined with the absorption system ammonia-air-water. Is is shown that the grid-structured plastic packing is highly efficient, particularly in terms of the hydraulic capacity compared with random plastic packings. Beside this, the main advantage of the packing is the easy handling and installation as well as the low investment costs compared to the well-known conventional corrugated structured packings.

  18. Consideration of grain packing in granular iron treatability studies

    NASA Astrophysics Data System (ADS)

    Firdous, R.; Devlin, J. F.

    2014-08-01

    Commercial granular iron (GI) is light steel that is used in Permeable Reactive Barriers (PRBs). Investigations into the reactivity of GI have focused on its chemical nature and relatively little direct work has been done to account for the effects of grain shape and packing. Both of these factors are expected to influence available grain surface area, which is known to correlate to reactivity. Commercial granular iron grains are platy and therefore pack in preferential orientations that could affect solution access to the surface. Three packing variations were investigated using Connelly Iron and trichloroethylene (TCE). Experimental kinetic data showed reaction rates 2-4 times higher when grains were packed with long axes preferentially parallel to flow (VP) compared to packings with long axes preferentially perpendicular to flow (HP) or randomly arranged (RP). The variations were found to be explainable by variations in reactive sorption capacities, i.e., sorption to sites where chemical transformations took place. The possibility that the different reactive sorption capacities were related to physical pore-scale differences was assessed by conducting an image analysis of the pore structure of sectioned columns. The analyses suggested that pore-scale factors - in particular the grain surface availability, reflected in the sorption capacity terms of the kinetic model used - could only account for a fraction of the observed reactivity differences between packing types. It is concluded that packing does affect observable reaction rates but that micro-scale features on the grain surfaces, rather than the pore scale characteristics, account for most of the apparent reactivity differences. This result suggests that treatability tests should consider the packing of columns carefully if they are to mimic field performance of PRBs to the greatest extent possible.

  19. Bin Packing - Optimization Online

    E-print Network

    Filipe Brandao

    2012-04-13

    However, the bin packing problem takes a list of items as input, while the cutting stock problem ..... For testing this model, we have done the following experiment. For each ..... Note that the average run time (tlp + tip) is less than 2 seconds.

  20. Economics Action Pack.

    ERIC Educational Resources Information Center

    McDonald's Corp., Oak Brook, IL.

    One of five McDonald's Action Packs, this learning package introduces intermediate grade students to basic economic concepts. The fourteen activities include the topics of consumption (4 activities), production (5), the market system (3), a pretest, and a posttest. Specific titles under consumption include The Wonderful Treasure Tree (introduction…

  1. Professional Training Information Pack

    E-print Network

    Davies, Christopher

    in the year, to check how the training is progressing. You will be regarded as an employee of the hostIntending Professional Training Students Year 2 Information Pack #12;- 1 - Applying for a Professional Training Placement To be allowed to do the Professional Training you must have enrolled on one

  2. Crystallization of pentagon packings

    Microsoft Academic Search

    Y. Limon Duparcmeur; A. Gervois; J. P. Troadec

    1995-01-01

    We present an experiment of densification of a 2D horizontal assembly made of regular pentagons. The annealing leads to a dense crystalline arrangement with quasisixfold symmetry in spite of the geometrical characteristics of the grains and of the a priori short-range correlation length in the packing. This configuration yields the maximum average number of side to side contacts between the

  3. Packing Them In.

    ERIC Educational Resources Information Center

    Carter, Claudia

    1997-01-01

    This activity involves students investigating the mathematics of packaging and exploring various concepts in geometry, including area and the Pythagorean theorem. Mathematics comes out of the discussion of packaging cans into six-packs and focuses on the cost-effectiveness of the horizontal storage area used. Students learn how knowledge of…

  4. Analysis of agglomerated packings

    Microsoft Academic Search

    A. V. Galakhov; E. V. Tsibailo; G. A. Fomina; B. S. Mitin

    1995-01-01

    Results of computer simulation of the packing of particles in compacts from agglomerated powders are presented. The effect of the characteristics of agglomerated powders, such as the number of particles in the agglomerates, the size distribution of agglomerates, and the volume share of the fine fraction (individual particles) on the factors that determine the sinterability of compacts, i.e., the density,

  5. Nutrition Action Pack.

    ERIC Educational Resources Information Center

    Sockut, Joanne; Stumpe, Stephanie

    One of five McDonald's Action Packs, these instructional materials integrate elementary school-level nutrition education into other disciplines--biology, sociology, physiology, mathematics, and art. Contents include four units consisting of twelve activities. Unit 1, Why You Need Food, is a self-examination of what is needed for growth, health,…

  6. A new procedure for the determination of distillation temperature distribution of high-boiling petroleum products and fractions.

    PubMed

    Boczkaj, Grzegorz; Przyjazny, Andrzej; Kami?ski, Marian

    2011-03-01

    The distribution of distillation temperatures of liquid and semi-fluid products, including petroleum fractions and products, is an important process and practical parameter. It provides information on properties of crude oil and content of particular fractions, classified on the basis of their boiling points, as well as the optimum conditions of atmospheric or vacuum distillation. At present, the distribution of distillation temperatures is often investigated by simulated distillation (SIMDIS) using capillary gas chromatography (CGC) with a short capillary column with polydimethylsiloxane as the stationary phase. This paper presents the results of investigations on the possibility of replacing currently used CGC columns for SIMDIS with a deactivated fused silica capillary tube without any stationary phase. The SIMDIS technique making use of such an empty fused silica column allows a considerable lowering of elution temperature of the analytes, which results in a decrease of the final oven temperature while ensuring a complete separation of the mixture. This eliminates the possibility of decomposition of less thermally stable mixture components and bleeding of the stationary phase which would result in an increase of the detector signal. It also improves the stability of the baseline, which is especially important in the determination of the end point of elution, which is the basis for finding the final temperature of distillation. This is the key parameter for the safety process of hydrocracking, where an excessively high final temperature of distillation of a batch can result in serious damage to an expensive catalyst bed. This paper compares the distribution of distillation temperatures of the fraction from vacuum distillation of petroleum obtained using SIMDIS with that obtained by the proposed procedure. A good agreement between the two procedures was observed. In addition, typical values of elution temperatures of n-paraffin standards obtained by the two procedures were compared. Finally, the agreement between boiling points of polar compounds determined from their retention times and actual boiling points was investigated. PMID:21153592

  7. Cadmium removal in a biosorption column

    SciTech Connect

    Volesky, B.; Prasetyo, I. (McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering)

    1994-05-01

    New biosorbent material derived from a ubiquitous brown marine alga Ascophyllum nodosum has been examined in packed-bed flow-through sorption columns. It effectively removed 10 mg/L of cadmium down to 1.5 ppb levels in the effluent, representing 99.985% removal. The experimental methodology used was based on the early Bohart and Adams sorption model, resulting in quantitative determination of the characteristic process parameters which can be used for performance comparison and process design. An average metal loading of the biosorbent (N[sub 0]) determined was 30 mg Cd/g, corresponding closely to that observed for the batch equilibrium metal concentration of 10 mg Cd/L. The critical bed depth (D[sub min]) for the potable water effluent quality standard varied with the column feed flow rate from 20 to 50 cm. The sorption column mass transfer and dispersion coefficients were determined, which are also required for solving the sorption model equations.

  8. Packed Bed Combustion: An Overview

    E-print Network

    Hallett, William L.H.

    Packed Bed Combustion: An Overview William Hallett Dept. of Mechanical Engineering Université d'Ottawa - University of Ottawa #12;Packed Bed Combustion - University of Ottawa - CICS 2005 Introduction air fuel feedproducts xbed grate Packed Bed Combustion: fairly large particles of solid fuel on a grate, air supplied

  9. Vapor Compression Distillation Flight Experiment

    NASA Technical Reports Server (NTRS)

    Hutchens, Cindy F.

    2002-01-01

    One of the major requirements associated with operating the International Space Station is the transportation -- space shuttle and Russian Progress spacecraft launches - necessary to re-supply station crews with food and water. The Vapor Compression Distillation (VCD) Flight Experiment, managed by NASA's Marshall Space Flight Center in Huntsville, Ala., is a full-scale demonstration of technology being developed to recycle crewmember urine and wastewater aboard the International Space Station and thereby reduce the amount of water that must be re-supplied. Based on results of the VCD Flight Experiment, an operational urine processor will be installed in Node 3 of the space station in 2005.

  10. Entanglement distillation from quasifree Fermions

    E-print Network

    Zoltan Kadar; Michael Keyl; Dirk Schlingemann

    2011-03-24

    We develop a scheme to distill entanglement from bipartite Fermionic systems in an arbitrary quasifree state. It can be applied if either one system containing infinite one-copy entanglement is available or if an arbitrary amount of equally prepared systems can be used. We show that the efficiency of the proposed scheme is in general very good and in some cases even optimal. Furthermore we apply it to Fermions hopping on an infinite lattice and demonstrate in this context that an efficient numerical analysis is possible for more then 10^6 lattice sites.

  11. Distillation of Bell states in open systems

    E-print Network

    E. Isasi; D. Mundarain

    2009-08-14

    In this work we review the entire classification of 2x2 distillable states for protocols with a finite numbers of copies. We show a distillation protocol that allows to distill Bell states with non zero probability at any time for an initial singlet in vacuum. It is shown that the same protocol used in non zero thermal baths yields a considerable recovering of entanglement.

  12. Enabling Microliquid Chromatography by Microbead Packing of Microchannels

    NASA Technical Reports Server (NTRS)

    Balvin, Manuel; Zheng, Yun

    2013-01-01

    The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid enantiomers.

  13. Enabling Microliquid Chromatography by Microbead Packing of Microchannels

    NASA Technical Reports Server (NTRS)

    Balvin, Manuel; Zheng, Yun

    2014-01-01

    The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid enantiomers.

  14. Temperature, pressure measurements solve column operating problems

    SciTech Connect

    Golden, S.W. [Process Consulting Services Inc., Grapevine, TX (United States)

    1995-12-25

    Refinery process engineers use computer modeling to design, monitor, operate, and troubleshoot refinery units. Basic chemical engineering principles, coupled with these high-technology tools, offer the engineer opportunities to identify and fix process unit problems. Pressure, temperature, and composition profiles are fundamental process measurements. But these simple tools that identify system design and operating problems are often lost among the more sophisticated high-tech tools. The details of three operations will show how these basic chemical engineering tools can be used to identify and solve operating problems in refinery distillation columns. Case 1 is an overhead crude unit; the second is a deethanizer reboiler; and the third is a crude atmospheric column.

  15. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  16. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  17. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  18. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  19. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  20. Five points on columns

    E-print Network

    Rockland, Kathleen

    Column,” like “gene,” has both conceptual and linguistic shortcomings. The simple question “what is a column” is not easy to answer and the word itself is not easy to replace. In the present article, I have selected five ...

  1. Quality evaluation of agricultural distillates using different types of electronic noses

    NASA Astrophysics Data System (ADS)

    Dymerski, Tomasz; Gebicki, Jacek; Namie?nik, Jacek

    2014-08-01

    The paper presents the results of investigation on quality evaluation of agricultural distillates using a prototype of electronic nose instrument and a commercial electronic nose of Fast/Flash GC type- HERACLES II. The prototype was equipped with TGS type semiconductor sensors. HERACLES II included two chromatographic columns with different polarity of stationary phase and two FID detectors. In case of the prototype volatile fraction of the agricultural distillate was prepared via barbotage process, whereas HERACLES II analysed the headspace fraction. Classification of the samples into three quality classes was performed using: quadratic discriminant function (QDA), supported with cross-validation method. Over 95% correct classification of the agricultural distillates into particular quality classes was observed for the analyses with HERACLES II. The prototype of electronic nose provided correct classification at the level of 70%.

  2. Starch columns: Analog model for basalt columns

    NASA Astrophysics Data System (ADS)

    Müller, Gerhard

    1998-07-01

    Desiccation of starch-water mixtures produces tensile-crack patterns which appear to be interesting, but largely unknown study objects for fracture mechanics, structural geology, and volcanology. This paper concentrates on columnar jointing and on columns in starch. Starch columns have polygonal cross sections and are very similar to basalt columns. They are produced by lamp drying starch specimens with dimensions of several centimeters and have diameters in the millimeter range. The columns develop behind a crack front which propagates from the surface into the interior. The experiments, supported by X ray tomograms, show that polygonal regularity of the crack pattern is not present at the surface but develops during penetration. This transition is steered by a minimum-fracture-energy principle. The analogy between basalt cooling and starch desiccation is far reaching: water concentration in starch is analogous to temperature in basalt, both quantities obey diffusion equations, water loss is equivalent to heat loss, the resulting contraction stresses have similar dependences on depth and time, and in both cases the material strength is exceeded. The starch experiments show that column diameters are controlled by the depth gradient of water concentration at the crack front. High (low) gradients are connected with thin (thick) columns. By analogy, a similar relation with the temperature gradient exists for basalt columns. The (normalized) starch gradients are about 3 orders of magnitude larger than the (normalized) gradients in basalt. This explains why starch columns are much thinner than basalt columns. The gradients are so different, because the crack front speeds differ by a factor of about 10: after 3 days the speed is about 10 mm/d in starch but about 100 mm/d in basalt [Peck, 1978]. The speed difference, in turn, results from the difference of the diffusion constants: the hydraulic diffusivity of starch is 2 orders of magnitude lower than the thermal diffusivity of basalt.

  3. JCE Feature Columns

    Microsoft Academic Search

    Jon L. Holmes

    1999-01-01

    The Features area of JCE Online is now readily accessible through a single click from our home page. In the Features area each column is linked to its own home page. These column home pages also have links to them from the online Journal Table of Contents pages or from any article published as part of that feature column. Using

  4. Separation of fructooligosaccharides using zeolite fixed bed columns

    Microsoft Academic Search

    Raquel Cristine Kuhn; Francisco Maugeri Filho

    2010-01-01

    Recent studies have shown that the chromatographic separation of mixtures of monosaccharides and disaccharides may be improved by employing Y zeolites, a procedure which holds promise in the separation of oligosaccharides. In the present study, a column packed with zeolite was employed to study the separation of fructooligosaccharides (FOS). FOS were produced by an enzyme isolated from Rhodotorula sp., which

  5. Use of granular slag columns for lead removal

    Microsoft Academic Search

    S. V Dimitrova

    2002-01-01

    The use of granular blast furnace slag (GBFS)-packed columns to treat lead-containing solutions has been investigated. The results obtained indicated that the slag usage rate decreased with increasing flow velocity, particle size, initial lead concentration and decreasing with bed height. Lead removed selectively in the presence of other heavy metal ions. High concentrations of sodium and especially calcium in the

  6. Recycling of Waste Acetone by Fractional Distillation

    ERIC Educational Resources Information Center

    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…

  7. The distillation and volatility of ionic liquids

    Microsoft Academic Search

    Martyn J. Earle; José M. S. S. Esperança; Manuela A. Gilea; José N. Canongia Lopes; Luís P. N. Rebelo; Joseph W. Magee; Kenneth R. Seddon; Jason A. Widegren

    2006-01-01

    It is widely believed that a defining characteristic of ionic liquids (or low-temperature molten salts) is that they exert no measurable vapour pressure, and hence cannot be distilled. Here we demonstrate that this is unfounded, and that many ionic liquids can be distilled at low pressure without decomposition. Ionic liquids represent matter solely composed of ions, and so are perceived

  8. Distillability Criterion for all Bipartite Gaussian States

    E-print Network

    G. Giedke; L. -M. Duan; J. I. Cirac; P. Zoller

    2001-10-09

    We prove that all inseparable Gaussian states of two modes can be distilled into maximally entangled pure states by local operations. Using this result we show that a bipartite Gaussian state of arbitrarily many modes can be distilled if and only if its partial transpose is not positive.

  9. Potential bleaching techniques for corn distillers grains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ethanol industry is booming, and extensive research is now being pursued to develop alternative uses for distillers dried grains (DDG) and distillers dried grains with solubles (DDGS), coproducts of the ethanol production process. Currently, DDG and DDGS are used exclusively as livestock feed. P...

  10. Membrane distillation. II. Direct contact MD

    Microsoft Academic Search

    Kevin W. Lawson; Douglas R. Lloyd

    1996-01-01

    Pure water direct contact membrane distillation (DCMD) experiments were used to measure the permeability parameter associated with the molecular diffusion in membrane distillation (MD). The fluxes given by a recently reported MD model, which is based on the dusty-gas model of gas transport through porous media, showed good agreement with the experimental results over the entire range of feed temperatures

  11. Rank three bipartite entangled states are distillable

    E-print Network

    Lin Chen; Yi-Xin Chen

    2008-03-07

    We prove that the bipartite entangled state of rank three is distillable. So there is no rank three bipartite bound entangled state. By using this fact, We present some families of rank four states that are distillable. We also analyze the relation between the low rank state and the Werner state.

  12. Locally Accessible Information and Distillation of Entanglement

    E-print Network

    Sibasish Ghosh; Pramod Joag; Guruprasad Kar; Samir Kunkri; Anirban Roy

    2004-03-18

    A new type of complementary relation is found between locally accessible information and final average entanglement for given ensemble. It is also shown that in some well known distillation protocol, this complementary relation is optimally satisfied. We discuss the interesting trade-off between locally accessible information and distillable entanglement for some states.

  13. Relativity and Lorentz Invariance of Entanglement Distillability

    E-print Network

    L. Lamata; M. A. Martin-Delgado; E. Solano

    2007-01-04

    We study entanglement distillability of bipartite mixed spin states under Wigner rotations induced by Lorentz transformations. We define weak and strong criteria for relativistic isoentangled and isodistillable states to characterize relative and invariant behavior of entanglement and distillability. We exemplify these criteria in the context of Werner states, where fully analytical methods can be achieved and all relevant cases presented.

  14. Distillation of Bell states in open systems

    SciTech Connect

    Isasi, E.; Mundarain, D. [Departamento de Fisica, Seccion de Fenomenos Opticos, Universidad Simon Bolivar, Apartado Postal 89000, Caracas 1080A (Venezuela, Bolivarian Republic of)

    2010-04-15

    In this work we show that the distillation protocol proposed by P. Chen et al. [Phys. Rev. A 54, 3824 (1996)] allows one to distill Bell states at any time for a system evolving in vacuum and prepared in an initial singlet. It is also shown that the same protocol, applied in nonzero temperature thermal baths, yields a considerable recovering of entanglement.

  15. Distillability of entanglement in accelerated frames

    E-print Network

    Moradi, Shahpoor

    2012-01-01

    We study the entanglement distillability of bipartite mixed states of two modes of a free Dirac field as seen by two relatively accelerated parties. It is shown that there are states that will change from distillable into separable for a certain value of acceleration. We exemplify these criteria in the context of Werner states.

  16. Heat transport in the membrane distillation process

    Microsoft Academic Search

    Marek Gryta; Maria Tomaszewska

    1998-01-01

    Investigation of membrane distillation (MD) with a laminar flow of the streams in a module has been performed. The equations describing the heat transfer in MD capillary modules were presented and verified experimentally. The equations were derived for the calculation of the feed and distillate temperature at a layer adjacent to the membrane. The heat transfer correlations were implemented in

  17. Distillability of entanglement in accelerated frames

    E-print Network

    Shahpoor Moradi

    2012-01-06

    We study the entanglement distillability of bipartite mixed states of two modes of a free Dirac field as seen by two relatively accelerated parties. It is shown that there are states that will change from distillable into separable for a certain value of acceleration. We exemplify these criteria in the context of Werner states.

  18. Water Purification by Membrane Distillation Process

    Microsoft Academic Search

    Marek Gryta

    2006-01-01

    The demineralization of water by membrane distillation (MD) has been investigated. In the first stage of investigations the tap water or boiled tap water was employed as a feed, and the water recovery coefficient exceeding 75% was achieved. The obtained concentrate was supplied to the second stage of MD installation. The quality of distillate was stable and practically independent of

  19. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect

    Riggs, J.B.

    1996-11-01

    Detailed dynamic simulations of two industrial distillation columns (a propylene/propane splitter and a xylene/toluene column) have been used to study the issue of configuration selection for diagonal PI dual composition controls. Auto Tune Variation (ATV) identification with on-line detuning was used for tuning the diagonal proportional integral (PI) composition controls. Each configuration was evaluated with respect to steady-state relative gain array (RGA) values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity) were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  20. Investigation of the Influence of Particle Size on the Productivity of Preparative HPLC Columns

    Microsoft Academic Search

    Joan Newburger; Leonard Liebes; Henri Colin; Georges Guiochon

    1987-01-01

    Changes in band profile, resolution, production, and yield with increasing sample size were determined for 1? i.d. × 12? preparative columns packed with 10 or 40 urn silica particles of the same origin. The results for a pure compound and for a mixture are compared. When a pure compound is injected, the efficiency of both columns decreases with increasing sample

  1. TRANSPORT OF MACROMOLECULES AND HUMATE COLLOIDS THROUGH A SAND AND A CLAY AMENDED SAND LABORATORY COLUMN

    EPA Science Inventory

    Laboratory experiments were conducted to determine if macromolecules or humate colloids would transport through sand columns and if they would exhibit any variations in their relative velocity based upon their molecular volumes and the pore size distribution of the column packing...

  2. DESIGN SCALE-UP SUITABILITY FOR AIR-STRIPPING COLUMNS (JOURNAL VERSION)

    EPA Science Inventory

    An investigation was conducted to determine the suitability of a design scale-up from pilot-scale to full-scale air-stripping columns used in the removal of volatile organic compounds from contaminated water supplies. Forty-eight experimental runs were made in packed columns of f...

  3. An aggregation model reduction method for one-dimensional distributed systems

    E-print Network

    Skogestad, Sigurd

    , or continuous, like packed distillation columns, fixed-bed reactors, and heat exchangers. A special class example systems, namely a distillation column, a heat exchanger, and a fixed-bed reactor. Keywords Model

  4. An Aggregation Model Reduction Method for One-Dimensional Distributed Systems

    E-print Network

    Skogestad, Sigurd

    packed distillation columns, fixed-bed reactors, and heat exchangers. A special class of discrete systems a distillation column, a heat exchanger, and a fixed-bed reactor. VVC 2011 Ameri- can Institute of Chemical

  5. Granular packings and fault zones

    PubMed

    Astrom; Herrmann; Timonen

    2000-01-24

    The failure of a two-dimensional packing of elastic grains is analyzed using a numerical model. The packing fails through formation of shear bands or faults. During failure there is a separation of the system into two grain-packing states. In a shear band, local "rotating bearings" are spontaneously formed. The bearing state is favored in a shear band because it has a low stiffness against shearing. The "seismic activity" distribution in the packing has the same characteristics as that of the earthquake distribution in tectonic faults. The directions of the principal stresses in a bearing are reminiscent of those found at the San Andreas Fault. PMID:11017335

  6. Cascade Distiller System Performance Testing Interim Results

    NASA Technical Reports Server (NTRS)

    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.

  7. Low capital implementation of distributed distillation in ethylene recovery

    SciTech Connect

    Reyneke, Rian; Foral, Michael J.; Lee, Guang-Chung

    2006-10-31

    An apparatus for recovering ethylene from a hydrocarbon feed stream, where the apparatus is a single distillation column pressure shell encasing an upper region and a lower region. The upper region houses an ethylene distributor rectifying section and the lower region houses a C2 distributor section and an ethylene distributor stripping section. Vapor passes from the lower region into the upper region, and liquid passes from the upper region to the lower region. The process for recovering the ethylene is also disclosed. The hydrocarbon feed stream is introduced into the C2 distributor section, and after a series of stripping and refluxing steps, distinct hydrocarbon products are recovered from the C2 distributor section, the ethylene distributor stripping section, and the ethylene distributor rectifying section, respectively.

  8. Hysteresis in column systems

    NASA Astrophysics Data System (ADS)

    Ivanyi, P.; Ivanyi, A.

    2015-02-01

    In this paper one column of a telescopic construction of a bell tower is investigated. The hinges at the support of the column and at the connecting joint between the upper and lower columns are modelled with rotational springs. The characteristics of the springs are assumed to be non-linear and the hysteresis property of them is represented with the Preisach hysteresis model. The mass of the columns and the bell with the fly are concentrated to the top of the column. The tolling process is simulated with a cycling load. The elements of the column are considered completely rigid. The time iteration of the non-linear equations of the motion is evaluated by the Crank-Nicolson schema and the implemented non-linear hysteresis is handled by the fix-point technique. The numerical simulation of the dynamic system is carried out under different combination of soft, medium and hard hysteresis properties of hinges.

  9. On two-distillable Werner states

    E-print Network

    Dragomir Z. Djokovic

    2010-03-23

    We consider bipartite mixed states in a d x d quantum system with d at least 3. We say that such a state is PPT if its partial transpose is positive semidefinite, and otherwise that it is NPT. The well-known Werner states are partitioned into three types: a) the separable states (same as the PPT states), b) the 1-distillable states (necessarily NPT), and c) the NPT states which are not 1-distillable. We give several different formulations and provide further evidence for validity of the conjecture that the type c) Werner states are not 2-distillable.

  10. New catalysts for hydrotreating heavy distillates

    SciTech Connect

    Chagovets, A.N.; Agafonov, A.V.; Lebedev, B.L.; Osipov, L.N.; Perezhigina, I.Ya.

    1982-11-01

    Compares the activity of experimental-commercial batches of type GO catalysts with the activity of alumina-cobaltmolybdenum (ACM) and alumina-nickel-molybdenum silicate (ANMS) catalysts in the hydrodesulfurization of a 350-500C vacuum distillate from Romashkino crude containing 2% sulfur and 0.1% nitrogen by weight. Finds that the GO-115, GO-116, and GO-117 catalysts are promising materials for use in hydrotreating vacuum distillates because their activities are higher than those of the commercial ACM and ANMS catalysts. Notes that the GO catalysts will give effective processing of vacuum distillates down to residual sulfur contents below 0.3% by weight.

  11. Preparation of a super-long two column chromatography system and its application in separating glycosylated puerarin.

    PubMed

    Zhu, Shouchuang; Xu, Haidong; Yu, Cigang; Ding, Juanfang; Chen, Ting; Jiang, Jierong; Dai, Yijun; Liu, Guiyou; Huang, Guodong; Chai, Nan; Jiang, Xuhua; Yuan, Sheng

    2009-12-01

    Separation of Puerarin-7-O-glucoside from its precursor, puerarin, using a common chromatography column packed with AB-8 macroporous resin was unsuccessful. Therefore, in this study a 8 m super-long flexible reinforced PVC column was externally added to the common column in order to improve the chromatography efficiency by increasing the number of theoretical plates. Both the PVC and common columns were separately packed with AB-8 macroporous resin slurry. The packed PVC column was coiled after washing and stored until use. The microbial transformation mixture with puerarin-7-O-glucoside and puerarin (250 mL) was loaded onto the common column, followed by washing with 2000 mL H(2)O. After attaching the coiled external PVC column to the common column, a linear gradient of 10-30% ethanol was applied to elute the target compound. Two peaks appeared: peak I contained puerarin-7-O-glucoside at 97.9% purity and 88.1% recovery rate, and peak II was puerarin at 98.7% purity and 87.0% recovery rate. The use of the coiled external flexible reinforced PVC column avoided spatial restriction for long columns, which made it much more convenient for column packing and chromatography operations. Furthermore, this method eliminated the resin blockage problem caused by stationary water pressure in a rigid vertical long column. Using an external super-long column, the PVC tube was connected with the common column only during elution, which avoided delay in time period during sample loading and column washes associated with the use of long external columns. PMID:19603387

  12. Radial distribution of the flow velocity, efficiency and concentration in a wide HPLC column

    Microsoft Academic Search

    Tivadar Farkas; Michael J. Sepaniak; Georges Guiochon

    1997-01-01

    The use of optical fibers in a fluorescence-detection scheme permits the accurate determination of the radial distribution of the transit time, the column efficiency, and the analyte concentration at the exit of a chromatographic axial-compression column (50 mmID). The results obtained demonstrate that the column is not homogeneous, but suggest a nearly cylindrical distribution of the packing density. The average

  13. Continuous-flow fractionation of selenium in contaminated sediment and soil samples using rotating coiled column and microcolumn extraction.

    PubMed

    Savonina, Elena Yu; Fedotov, Petr S; Wennrich, Rainer

    2012-01-15

    Dynamic fractionation is considered to be an attractive alternative to conventional batch sequential extraction procedures for partitioning of trace metals and metalloids in environmental solid samples. This paper reports the first results on the continuous-flow dynamic fractionation of selenium using two different extraction systems, a microcolumn (MC) packed with the solid sample and a rotating coiled column (RCC) in which the particulate matter is retained under the action of centrifugal forces. The eluents (leachants) were applied in correspondence with a four-step sequential extraction scheme for selenium addressing "soluble", "adsorbed", "organically bound", and "elemental" Se fractions extractable by distilled water, phosphate buffer, tetramethylammonium hydroxide, and sodium sulphite solutions, respectively. Selenium was determined in the effluent by using an inductively coupled plasma atomic emission spectrometer. Contaminated creek sediment and dumped waste (soil) samples from the abandoned mining area were used to evaluate resemblances and discrepancies of two continuous-flow methods for Se fractionation. In general, similar trends were found for Se distribution between extractable and residual fractions. However, for the dumped waste sample which is rich in organic matter, the extraction in RCC provided more effective recovery of environmentally relevant Se forms (the first three leachable fractions). The most evident deviation was observed for "adsorbed" Se (recoveries by RCC and MC are 43 and 7 mg kg(-1), respectively). The data obtained were correlated with peculiarities of samples under investigation and operational principles of RCC and MC. PMID:22265512

  14. Packing Products: Polystyrene vs. Cornstarch

    ERIC Educational Resources Information Center

    Starr, Suzanne

    2009-01-01

    Packing materials such as polystyrene take thousands of years to decompose, whereas packing peanuts made from cornstarch, which some companies are now using, can serve the same purpose, but dissolve in water. The author illustrates this point to her class one rainy day using the sculptures students made from polystyrene and with the cornstarch…

  15. Response of Jammed Ellipsoid Packings

    Microsoft Academic Search

    Zorana Zeravcic; Andrea Liu; Sidney Nagel

    2011-01-01

    We investigate the nature of the jamming transition for packings of spheroids by examining the elastic moduli as a function of the aspect ratio of the particles ? and the compression. Irrespective of the particle aspect ratio, both shear modulus G and bulk modulus B show the same scaling as a function of compression as is found for packings of

  16. Energy Recovery in Industrial Distillation Processes

    E-print Network

    Paul, D. B.

    1983-01-01

    temperatures resulting in significant energy savings. The distillation process will be reviewed as it relates to both vapor recompression and heat pumping techniques and case study examples of these energy recovery methods will be discussed....

  17. Development of energy efficient membrane distillation systems

    E-print Network

    Summers, Edward K

    2013-01-01

    Membrane distillation (MD) has shown potential as a means of desalination and water purification. As a thermally driven membrane technology which runs at relatively low pressure, which can withstand high salinity feed ...

  18. Distillation modeling for a uranium refining process

    SciTech Connect

    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.

  19. On the irreversibility of entanglement distillation

    E-print Network

    K. G. H. Vollbrecht; R. F. Werner; M. M. Wolf

    2003-01-15

    We investigate the irreversibility of entanglement distillation for a symmetric d-1 parameter family of mixed bipartite quantum states acting on Hilbert spaces of arbitrary dimension d x d. We prove that in this family the entanglement cost is generically strictly larger than the distillable entanglement, such that the set of states for which the distillation process is asymptotically reversible is of measure zero. This remains true even if the distillation process is catalytically assisted by pure state entanglement and every operation is allowed, which preserves the positivity of the partial transpose. It is shown, that reversibility occurs only in cases where the state is quasi-pure in the sense that all its pure state entanglement can be revealed by a simple operation on a single copy. The reversible cases are shown to be completely characterized by minimal uncertainty vectors for entropic uncertainty relations.

  20. An improved model for multiple effect distillation

    E-print Network

    Mistry, Karan H.

    Increasing global demand for fresh water is driving research and development of advanced desalination technologies. As a result, a detailed model of multiple effect distillation (MED) is developed that is flexible, simple ...

  1. Nonlocality Distillation for High-Dimensional System

    E-print Network

    Pan, Guo-Zhu; Chen, Zheng-Gen; Yang, Ming; Cao, Zhuo-Liang

    2012-01-01

    The intriguing and powerful capability of nonlocality in communication field ignites the research of the nonlocality distillation. The first protocol presented in Ref[Phys. Rev. Lett. 102, 120401] shows that the nonlocality of bipartite binary-input and binary-output nonsignaling correlated boxes could be amplified by 'wiring' two copies of weaker-nonlocality boxes. Several optimized distillation protocols were presented later for bipartite binary-input and binary-output nonsignaling correlated boxes. In this paper, we focus on the bipartite binary-input and multi-nary-output nonsignaling correlated boxes---high-dimensional boxes, and design comparators-based protocols to achieve the distillation of high-dimensional nonlocality. The results show that the high-dimensional nonlocality can be distilled in different ways, and we find that the efficiencies of the protocols are influenced not only by the wirings but also by the classes the initial nonlocality boxes belongs to. Here, the initial nonlcalities may hav...

  2. Energy Conservation Options in Distillation Processes

    E-print Network

    Harris, G. E.; Hearn, W. R.; Blythe, G. M.; Stuart, J. M.

    1980-01-01

    This paper summarizes the results of a survey of energy conservation options applicable to distillation processes. Over twenty such options were identified, and eight of these were selected for detailed presentation. These options were chosen...

  3. Multipartite secret key distillation and bound entanglement

    SciTech Connect

    Augusiak, Remigiusz; Horodecki, Pawel [Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk (Poland) and ICFO-Institute Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona) (Spain); Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk (Poland)

    2009-10-15

    Recently it has been shown that quantum cryptography beyond pure entanglement distillation is possible and a paradigm for the associated protocols has been established. Here we systematically generalize the whole paradigm to the multipartite scenario. We provide constructions of new classes of multipartite bound entangled states, i.e., those with underlying twisted Greenberger-Horne-Zeilinger (GHZ) structure and nonzero distillable cryptographic key. We quantitatively estimate the key from below with the help of the privacy squeezing technique.

  4. Use of computers for multicomponent distillation calculations

    E-print Network

    Sullivan, Samuel Lane

    1959-01-01

    LIBRARY 4 A I4 COLLEGE QF TEXAS USE OF COMPUTERS FOB MULTICOMPONENT DISTILLATION CALCULATIONS A Thesis By Samuel Lane Sullivan Jr, Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE January 1959 Major Subject: Chemical Engineering USE OF COMPUTERS FOR NULTICOMPONENT DISTILLATION CALCULATIONS A Thesis By Samuel Lane Sullivan Jr. Approved as to style and content by: Chairman...

  5. Steering Distillation by "Pulsed" and "Continuous" Measurements

    E-print Network

    B. Militello; H. Nakazato; A. Messina

    2004-05-14

    A new systematic strategy for steering the distillation process for a quantum system, that utilizes the so-called "pulsed" and "continuous" measurements on another quantum system in interaction with the former, is proposed. The distillation process characterized by the specific interaction between the two systems and the "pulsed" measurements is shown to be controllable through the "continuous" measurements, i.e., the quantum Zeno dynamics, providing an effective recipe to prefix the target.

  6. Multipartite secret key distillation and bound entanglement

    E-print Network

    Remigiusz Augusiak; Pawel Horodecki

    2009-09-25

    Recently it has been shown that quantum cryptography beyond pure entanglement distillation is possible and a paradigm for the associated protocols has been established. Here we systematically generalize the whole paradigm to the multipartite scenario. We provide constructions of new classes of multipartite bound entangled states, i.e., those with underlying twisted GHZ structure and nonzero distillable cryptographic key. We quantitatively estimate the key from below with help of the privacy squeezing technique.

  7. New catalysts for hydrotreating heavy distillates

    Microsoft Academic Search

    A. N. Chagovets; L. N. Osipov; B. L. Lebedev; I. Ya. Perezhigina; A. V. Agafonov

    1982-01-01

    Compares the activity of experimental-commercial batches of type GO catalysts with the activity of alumina-cobaltmolybdenum (ACM) and alumina-nickel-molybdenum silicate (ANMS) catalysts in the hydrodesulfurization of a 350-500C vacuum distillate from Romashkino crude containing 2% sulfur and 0.1% nitrogen by weight. Finds that the GO-115, GO-116, and GO-117 catalysts are promising materials for use in hydrotreating vacuum distillates because their activities

  8. On the Communication Complexity of Correlation and Entanglement Distillation

    E-print Network

    On the Communication Complexity of Correlation and Entanglement Distillation Ke Yang May 4th, 2004 distillation, entanglement distillation, communication complexity, EPR pairs, quantum key distribution #12) information, and then engage in a protocol to \\distill" the correlation/entanglement via communication. We

  9. Complex Fluid Analysis with the Advanced Distillation Curve Approach

    E-print Network

    Complex Fluid Analysis with the Advanced Distillation Curve Approach Thomas J. Bruno, Lisa S. Ott for measuring distillation curves reveals the physicochemical properties of complex fluids such as fuels distillation curves of complex fluids. The distillation curve provides the only practical avenue to assess

  10. Blog Distillation via Sentiment-Sensitive Link Analysis

    E-print Network

    Sebastiani, Fabrizio

    Blog Distillation via Sentiment-Sensitive Link Analysis Giacomo Berardi, Andrea Esuli, Fabrizio blog distillation by adding a link analysis phase to the standard retrieval-by-topicality phase, where in blog distillation. 1 Introduction Blog distillation is a subtask of blog search. It is defined

  11. Solution of systems of columns with energy exchange between recycle streams

    E-print Network

    Haas, Joe Ray

    1980-01-01

    relationships, the material balances and the energy balances of the streams that pass across the enclosures of each column or unit of the system. At the end of each trial through the system, the capital theta method is used to find a set or values... recycle streams. The convergence method for a conventional distillation column where the reflux ratio and the boilup ratio are specified is based on finding the variables which satisfy the material balances, energy balances and equilibrium...

  12. Resonant column test

    Microsoft Academic Search

    V. P. Drnevich

    1978-01-01

    The resonant column test is used to determine by vibration the shear modulus, shear damping, rod modulus (Young's modulus) and rod damping of cylindrical specimens of soil in the undisturbed and remolded conditions. The vibration apparatus, apparatus calibration, and calculations are described. The reduction of all resonant column test data is presented in a computer program.

  13. Support Column of Bridge

    USGS Multimedia Gallery

    Support column of bridge across Struve Slough, Highway 1. Enlargement of hole where support enters the ground is an effect of lateral shaking, which caused the concrete to break up where the column joined the bridge and was instrumental in the roadbed collapse....

  14. Quantum Nonlocal Boxes Exhibit Stronger Distillability

    E-print Network

    Høyer, Peter

    2012-01-01

    The hypothetical nonlocal box (\\textsf{NLB}) proposed by Popescu and Rohrlich allows two spatially separated parties, Alice and Bob, to exhibit stronger than quantum correlations. If the generated correlations are weak, they can sometimes be distilled into a stronger correlation by repeated applications of the \\textsf{NLB}. Motivated by the limited distillability of \\textsf{NLB}s, we initiate here a study of the distillation of correlations for nonlocal boxes that output quantum states rather than classical bits (\\textsf{qNLB}s). We propose a new protocol for distillation and show that it asymptotically distills a class of correlated quantum nonlocal boxes to the value $1/2 (3\\sqrt{3}+1) \\approx 3.098076$, whereas in contrast, the optimal non-adaptive parity protocol for classical nonlocal boxes asymptotically distills only to the value 3.0. We show that our protocol is an optimal non-adaptive protocol for 1, 2 and 3 \\textsf{qNLB} copies by constructing a matching dual solution for the associated primal semid...

  15. JCE Feature Columns

    NASA Astrophysics Data System (ADS)

    Holmes, Jon L.

    1999-05-01

    The Features area of JCE Online is now readily accessible through a single click from our home page. In the Features area each column is linked to its own home page. These column home pages also have links to them from the online Journal Table of Contents pages or from any article published as part of that feature column. Using these links you can easily find abstracts of additional articles that are related by topic. Of course, JCE Online+ subscribers are then just one click away from the entire article. Finding related articles is easy because each feature column "site" contains links to the online abstracts of all the articles that have appeared in the column. In addition, you can find the mission statement for the column and the email link to the column editor that I mentioned above. At the discretion of its editor, a feature column site may contain additional resources. As an example, the Chemical Information Instructor column edited by Arleen Somerville will have a periodically updated bibliography of resources for teaching and using chemical information. Due to the increase in the number of these resources available on the WWW, it only makes sense to publish this information online so that you can get to these resources with a simple click of the mouse. We expect that there will soon be additional information and resources at several other feature column sites. Following in the footsteps of the Chemical Information Instructor, up-to-date bibliographies and links to related online resources can be made available. We hope to extend the online component of our feature columns with moderated online discussion forums. If you have a suggestion for an online resource you would like to see included, let the feature editor or JCE Online (jceonline@chem.wisc.edu) know about it. JCE Internet Features JCE Internet also has several feature columns: Chemical Education Resource Shelf, Conceptual Questions and Challenge Problems, Equipment Buyers Guide, Hal's Picks, Mathcad in the Chemistry Curriculum, and WWW Site Review. These columns differ from the print feature columns in that they use the Internet as the publication medium. Doing so allows these features to include continually updated information, digital components, and links to other online resources. The Conceptual Questions and Challenge Problems feature of JCE Internet serves as a good example for the kinds of resources that you can expect to find in an online feature column. Like other columns it contains a mission statement that defines the role of the column. It includes a digital library of continually updated examples of conceptual questions and challenge problems. (As I write this we have just added several new questions to the library.) It also includes a list of links to related online resources, information for authors about how to write questions and problems, and information for teachers about how to use conceptual questions and challenge problems. Teaching with Technology home page at JCE Online. One-Stop Feature Shop The updated Feature area of JCE Online offers information about all JCE feature columns in one place. It gives you a quick and convenient way to access a group of articles in a particular subject area. It provides authors and readers with a good definition of the column and its mission. It complements the print feature columns with online resources. It provides up-to-date bibliographies for selected areas of interest. And last, but not least, it provides that email address you can use to send that message of appreciation to the feature editor for his or her contribution to JCE and the chemical education community.

  16. Glass-silicon column

    DOEpatents

    Yu, Conrad M.

    2003-12-30

    A glass-silicon column that can operate in temperature variations between room temperature and about 450.degree. C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

  17. Evaluation of thermal catalytic decomposition of organic compounds with TiO2 by packed-capillary gas chromatography.

    PubMed

    Ueta, Ikuo; Mizuguchi, Ayako; Tani, Kazue; Kawakubo, Susumu; Saito, Yoshihiro

    2014-01-01

    A novel method for evaluating the thermal catalytic decomposition of organic compounds on a solid acid catalyst was developed using a capillary gas chromatography-flame ionization detector (GC-FID) equipped with a packed-capillary column. The thermal catalytic decomposition of various organic compounds was investigated by introducing gaseous or liquid organic compounds into a heated test tube packed with TiO2 particles. The resulting carbon monoxide (CO) and carbon dioxide (CO2) in the test tube were determined in a conventional capillary GC system with a methanizer after separation on a packed-capillary column. In the packed-capillary GC system, several parameters affecting thermal catalytic reactions of various organic compounds were successfully evaluated, such as the type of the catalysts and the effect of catalytic temperatures. Finally, a sequential decomposition of organic compounds was confirmed in the heated reaction tube packed with TiO2 particles. PMID:24614737

  18. Packed Bed Reactor Experiment - Duration: 17 seconds.

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  19. 7 CFR 51.3055 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... United States Standards for Florida Avocados Standard Pack § 51.3055 Standard pack. (a) The avocados shall be packed in accordance with...fruit in the container. Size of the avocados may be specified by count....

  20. 7 CFR 51.3055 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... United States Standards for Florida Avocados Standard Pack § 51.3055 Standard pack. (a) The avocados shall be packed in accordance with...fruit in the container. Size of the avocados may be specified by count....

  1. 7 CFR 51.3055 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... United States Standards for Florida Avocados Standard Pack § 51.3055 Standard pack. (a) The avocados shall be packed in accordance with...fruit in the container. Size of the avocados may be specified by count....

  2. 7 CFR 51.3055 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... United States Standards for Florida Avocados Standard Pack § 51.3055 Standard pack. (a) The avocados shall be packed in accordance with...fruit in the container. Size of the avocados may be specified by count....

  3. 7 CFR 51.3055 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... United States Standards for Florida Avocados Standard Pack § 51.3055 Standard pack. (a) The avocados shall be packed in accordance with...fruit in the container. Size of the avocados may be specified by count....

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

    PubMed

    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. PMID:25147909

  5. Valve stem and packing assembly

    DOEpatents

    Wordin, John J. (Bingham County, ID)

    1991-01-01

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents overtightening of the retaining nut and the resulting excessive friction between stem and stem packing.

  6. Valve stem and packing assembly

    DOEpatents

    Wordin, J.J.

    1991-09-03

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents over tightening of the retaining nut and the resulting excessive friction between stem and stem packing. 2 figures.

  7. Packing grains by thermally cycling

    E-print Network

    K. Chen; J. Cole; C. Conger; J. Draskovic; M. Lohr; K. Klein; T. Scheidemantel; P. Schiffer

    2006-08-04

    One of the oldest and most intriguing problems in the handling of materials is how a collection of solid grains packs together. While granular packing is normally determined by how grains are poured or shaken, we find that a systematic and controllable increase in packing is induced by simply raising and lowering the temperature, e.g., without the input of mechanical energy. The results demonstrate that thermal processing provides a largely unexplored mechanism of grain dynamics, as well as an important practical consideration in the handling and storage of granular materials.

  8. Effect of feeding distiller’s grains on reduced sulfur emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odorous reduced sulfur compounds are produced during manure decomposition and emitted from confined animal feeding operations. Feeding high-sulfur distiller’s byproducts may increase the emission of these compounds. The objectives of a series of feedlot pen studies was to (i) determine if emission...

  9. Radial distribution of the flow velocity, efficiency and concentration in a wide HPLC column

    SciTech Connect

    Farkas, T.; Sepaniak, M.J.; Guiochon, G. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry] [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry; [Oak Ridge National Lab., TN (United States). Div. of Chemical and Analytical Sciences

    1997-08-01

    The use of optical fibers in a fluorescence-detection scheme permits the accurate determination of the radial distribution of the transit time, the column efficiency, and the analyte concentration at the exit of a chromatographic axial-compression column (50 mmID). The results obtained demonstrate that the column is not homogeneous, but suggest a nearly cylindrical distribution of the packing density. The average velocity close to the column wall is 7% lower than along its axis and the HETP 25% higher. The lack of homogeneity of the column packing is another source of band broadening not taken into account in chromatography so far. It causes the apparent HETP derived from the conventional elution chromatogram recorded on the bulk eluent to be larger than the local HETP and the band profile to be unsymmetrical with a slight tail reminiscent of kinetic tailing.

  10. Isolation of natural products by low-pressure column chromatography.

    PubMed

    Reid, Raymond G; Sarker, Satyajit D

    2012-01-01

    This chapter describes the isolation of natural products using low-pressure column chromatography (LPLC) and provides a brief summary of the adsorption and size exclusion processes involved in LPLC. Different types of stationary phases used in both adsorption and size exclusion LPLC are also presented with specific examples. Various operational parameters in relation to column packing (both wet and dry), column equilibration, sample application, and column development, and a summary of generic procedures for adsorption and size exclusion LPLC are also incorporated in this chapter. Throughout the chapter, several specific examples of the application of LPLC for the isolation of various natural products including alkaloids, coumarins, flavones, and saponins from various plants are given. Many of these examples include a combination of adsorption and size exclusion chromatography to obtain specific compounds. PMID:22367897

  11. Optimal thermodynamic approximation to reversible distillation by means of interheaters and intercoolers

    SciTech Connect

    Aguirre, P.; Espinosa, J.; Tarifa, E.; Scenna, N. [CONICET, Santa Fe (Argentina)] [CONICET, Santa Fe (Argentina)

    1997-11-01

    The purpose of this paper is to deal with the problem of heat and power integration on one side and the problem of minimizing heat exchange areas on the other side, in both conventional and nonconventional distillation columns. The authors consider the limiting case of columns operating at minimum reflux. The appropriate objective functions that one must consider are the entropy production rate and the total heat exchange area, respectively. This is done by means of optimal placement of a given number of interheaters (IHs) and intercoolers (ICs) in stripping and rectifying sections, respectively. To solve these problems, an appropriate thermodynamic model for both conventional and nonconventional distillative columns is formally presented. This model allows one to formulate an optimization problem involving thermodynamically reversible profiles in stripping and rectifying sections of the columns. This approach differs from others previously reported in that multiple reversible profiles were identified for each section of the column which give rise to lower and upper bounds for the objective function of the minimization problem. In other words, the authors obtain two solutions for each column section: the first is a nonoptimal feasible one, and the second is an optimal but not necessarily feasible one. Finally, the comparison of this approach with a method based on pseudobinary reversible profiles is carried out. Optimizing with this curve, solutions will be generated with objective function values between the lower and upper bounds. Therefore, care would be taken in using a pseudobinary pinch point curve for the placement of intermediate heat-exchanger units especially when the difference between the upper and lower bounds for the objective function values is relatively great.

  12. Frac pack technology still evolving

    SciTech Connect

    Ebinger, C.D. [Ely and Associates Inc., Houston, TX (United States)

    1995-10-23

    Success of frac packs depends on candidate selection, treatment design, fluids and proppants, downhole tools, and treatment implementation. Current frac packing techniques have partially evolved from high-permeability stimulation in the Kuparuk field, Alaska. In the Gulf of Mexico (GOM), attempts were made as early as the mid-1960s to hydraulically fracture sands. These early treatments were not highly successful because of techniques, understanding of rock mechanical properties, and poor candidate selection. This article focuses primarily on frac packs in GOM wells, although this technique is also used in South America, Southeast Asia, Pakistan, Nigeria, Alaska, and Europe. Through mid-year 1995 in the GOM alone, there have been over 600 frac packs.

  13. Response of Jammed Ellipsoid Packings

    NASA Astrophysics Data System (ADS)

    Zeravcic, Zorana; Liu, Andrea; Nagel, Sidney

    2011-03-01

    We investigate the nature of the jamming transition for packings of spheroids by examining the elastic moduli as a function of the aspect ratio of the particles ? and the compression. Irrespective of the particle aspect ratio, both shear modulus G and bulk modulus B show the same scaling as a function of compression as is found for packings of spheres. Moreover, for any value of ?, G is proportional to the excess of the coordination number above that found at the jamming threshold; this recovers the result for frictionless spheres at ?=1. Our results imply a new diverging length scale associated with the loss of rigidity of these spheroid packings. The critical behavior of ellipsoid packings is an extension of that found for spheres.

  14. Local purity distillation with bounded classical communication

    E-print Network

    Hari Krovi; Igor Devetak

    2007-05-28

    Local pure states are an important resource for quantum computing. The problem of distilling local pure states from mixed ones can be cast in an information theoretic paradigm. The bipartite version of this problem where local purity must be distilled from an arbitrary quantum state shared between two parties, Alice and Bob, is closely related to the problem of separating quantum and classical correlations in the state and in particular, to a measure of classical correlations called the one-way distillable common randomness. In Phys. Rev. A 71, 062303 (2005), the optimal rate of local purity distillation is derived when many copies of a bipartite quantum state are shared between Alice and Bob, and the parties are allowed unlimited use of a unidirectional dephasing channel. In the present paper, we extend this result to the setting in which the use of the channel is bounded. We demonstrate that in the case of a classical-quantum system, the expression for the local purity distilled is efficiently computable and provide examples with their tradeoff curves.

  15. Soil column leaching of pesticides.

    PubMed

    Katagi, Toshiyuki

    2013-01-01

    In this review, I address the practical and theoretical aspects of pesticide soil mobility.I also address the methods used to measure mobility, and the factors that influence it, and I summarize the data that have been published on the column leaching of pesticides.Pesticides that enter the unsaturated soil profile are transported downwards by the water flux, and are adsorbed, desorbed, and/or degraded as they pass through the soil. The rate of passage of a pesticide through the soil depends on the properties of the pesticide, the properties of the soil and the prevailing environmental conditions.Because large amounts of many different pesticides are used around the world, they and their degradates may sometimes contaminate groundwater at unacceptable levels.It is for this reason that assessing the transport behavior and soil mobility of pesticides before they are sold into commerce is important and is one indispensable element that regulators use to assess probable pesticide safety. Both elementary soil column leaching and sophisticated outdoor lysimeter studies are performed to measure the leaching potential for pesticides; the latter approach more reliably reflects probable field behavior, but the former is useful to initially profile a pesticide for soil mobility potential.Soil is physically heterogeneous. The structure of soil varies both vertically and laterally, and this variability affects the complex flow of water through the soil profile, making it difficult to predict with accuracy. In addition, macropores exist in soils and further add to the complexity of how water flow occurs. The degree to which soil is tilled, the density of vegetation on the surface, and the type and amounts of organic soil amendments that are added to soil further affect the movement rate of water through soil, the character of soil adsorption sites and the microbial populations that exist in the soil. Parameters that most influence the rate of pesticide mobility in soil are persistence (DT50) of the pesticide, and its sorption/desorption(Koc) characteristics. These parameters may vary for the same pesticide from geographic site-to-site and with soil depth. The interactions that normally occur between pesticides and dissolved organic matter (DOM) or WDC are yet other factors that may complicate pesticide leaching behavior.The soil mobility of pesticides is normally tested both in the laboratory and in the field. Lab studies are initially performed to give researchers a preliminary appraisal of the relative mobility of a pesticide. Later, field lysimeter studies can be performed to provide more natural leaching conditions that emulate the actual field use pattern. Lysimeter studies give the most reliable information on the leaching behavior of a pesticide under field conditions, but these studies are time-consuming and expensive and cannot be performed everywhere. It is for this reason that the laboratory soil column leaching approach is commonly utilized to profile the mobility of a pesticide,and appraise how it behaves in different soils, and relative to other pesticides.Because the soil structure is chemically and physically heterogenous, different pesticide tests may produce variable DT50 and Koc values; therefore, initial pesticide mobility testing is undertaken in homogeneously packed columns that contain two or more soils and are eluted at constant flow rates. Such studies are done in duplicate and utilize a conservative tracer element. By fitting an appropriate mathematical model to the breakthrough curve of the conservative tracer selected,researchers determine key mobility parameters, such as pore water velocity, the column-specific dispersion coefficient, and the contribution of non equilibrium transport processes. Such parameters form the basis for estimating the probable transport and degradation rates that will be characteristic of the tested pesticide. Researchers also examine how a pesticide interacts with soil DOM and WDC, and what contribution from facilitated transport to mobility is made as a result of the effects of

  16. Are proteins well-packed?

    PubMed Central

    Liang, J; Dill, K A

    2001-01-01

    The average packing density inside proteins is as high as in crystalline solids. Does this mean proteins are well-packed? We go beyond average densities, and look at the full distribution functions of free volumes inside proteins. Using a new and rigorous Delaunay triangulation method for parsing space into empty and filled regions, we introduce formal definitions of interior and surface packing densities. Although proteins look like organic crystals by the criterion of average density, they look more like liquids and glasses by the criterion of their free volume distributions. The distributions are broad, and the scalings of volume-to-surface, volume-to-cluster-radius, and numbers of void versus volume show that the interiors of proteins are more like randomly packed spheres near their percolation threshold than like jigsaw puzzles. We find that larger proteins are packed more loosely than smaller proteins. And we find that the enthalpies of folding (per amino acid) are independent of the packing density of a protein, indicating that van der Waals interactions are not a dominant component of the folding forces. PMID:11463623

  17. Towards Atomic Column-by-Column Spectroscopy

    SciTech Connect

    Pennycook, S.J.; Rafferty, B.

    1998-09-06

    The optical arrangement of the scanning transmission electron microscope (STEM) is ideally suited for performing analysis of individual atomic columns in materials. Using the incoherent Z-contrast image as a reference, and arranging incoherent conditions also for the spectroscopy, a precise correspondence is ensured between features in the inelastic image and elastic signals. In this way the exact probe position needed to maximise the inelastic signal from a selected column can be located and monitored during the analysis using the much higher intensity elastic signal. Although object functions for EELS are typically less than 1 {Angstrom} full width at half maximum, this is still an order of magnitude larger than the corresponding object functions for elastic (or diffuse) scattering used to form the Z-contrast image. Therefore the analysis is performed with an effective probe that is significantly broader than that used for the reference Z-contrast image. For a 2.2 {Angstrom} probe the effective probe is of the order of 2.5 {Angstrom}, while for a 1.3 {Angstrom} probe the effective probe is 1.6 {Angstrom}. Such increases in effective probe size can significantly reduce or even eliminate contrast between atomic columns that are visible in the image. However, this is only true if we consider circular collector apertures. Calculations based upon the theory of Maslen and Rossouw (Maslen and Rossouw 1984; Rossouw and Maslen 1984) show that employing an annular aperture can reduce the FWHM of the inelastic object function down to values close 0.1 {Angstrom}. With practical aperture sizes it should be possible to achieve this increased spatial resolution without loosing too much signal.

  18. Entanglement distillation protocols and number theory

    SciTech Connect

    Bombin, H.; Martin-Delgado, M.A. [Departamento de Fisica Teorica I, Universidad Complutense, 28040 Madrid (Spain)

    2005-09-15

    We show that the analysis of entanglement distillation protocols for qudits of arbitrary dimension D benefits from applying basic concepts from number theory, since the set Z{sub D}{sup n} associated with Bell diagonal states is a module rather than a vector space. We find that a partition of Z{sub D}{sup n} into divisor classes characterizes the invariant properties of mixed Bell diagonal states under local permutations. We construct a very general class of recursion protocols by means of unitary operations implementing these local permutations. We study these distillation protocols depending on whether we use twirling operations in the intermediate steps or not, and we study them both analytically and numerically with Monte Carlo methods. In the absence of twirling operations, we construct extensions of the quantum privacy algorithms valid for secure communications with qudits of any dimension D. When D is a prime number, we show that distillation protocols are optimal both qualitatively and quantitatively.

  19. Distillation of local purity from quantum states

    E-print Network

    I. Devetak

    2004-06-30

    Recently Horodecki et al. [Phys. Rev. Lett. 90, 100402 (2003)] introduced an important quantum information processing paradigm, in which two parties sharing many copies of the same bipartite quantum state distill local pure states, by means of local unitary operations assisted by a one-way (two-way) completely dephasing channel. Local pure states are a valuable resource from a thermodynamical point of view, since they allow thermal energy to be converted into work by local quantum heat engines. We give a simple information-theoretical characterization of the one-way distillable local purity, which turns out to be closely related to a previously known operational measure of classical correlations, the one-way distillable common randomness.

  20. Entanglement Distillation Protocols and Number Theory

    E-print Network

    H. Bombin; M. A. Martin-Delgado

    2005-03-01

    We show that the analysis of entanglement distillation protocols for qudits of arbitrary dimension $D$ benefits from applying basic concepts from number theory, since the set $\\zdn$ associated to Bell diagonal states is a module rather than a vector space. We find that a partition of $\\zdn$ into divisor classes characterizes the invariant properties of mixed Bell diagonal states under local permutations. We construct a very general class of recursion protocols by means of unitary operations implementing these local permutations. We study these distillation protocols depending on whether we use twirling operations in the intermediate steps or not, and we study them both analitically and numerically with Monte Carlo methods. In the absence of twirling operations, we construct extensions of the quantum privacy algorithms valid for secure communications with qudits of any dimension $D$. When $D$ is a prime number, we show that distillation protocols are optimal both qualitatively and quantitatively.

  1. Quantum Nonlocal Boxes Exhibit Stronger Distillability

    E-print Network

    Peter Høyer; Jibran Rashid

    2012-04-20

    The hypothetical nonlocal box (\\textsf{NLB}) proposed by Popescu and Rohrlich allows two spatially separated parties, Alice and Bob, to exhibit stronger than quantum correlations. If the generated correlations are weak, they can sometimes be distilled into a stronger correlation by repeated applications of the \\textsf{NLB}. Motivated by the limited distillability of \\textsf{NLB}s, we initiate here a study of the distillation of correlations for nonlocal boxes that output quantum states rather than classical bits (\\textsf{qNLB}s). We propose a new protocol for distillation and show that it asymptotically distills a class of correlated quantum nonlocal boxes to the value $1/2 (3\\sqrt{3}+1) \\approx 3.098076$, whereas in contrast, the optimal non-adaptive parity protocol for classical nonlocal boxes asymptotically distills only to the value 3.0. We show that our protocol is an optimal non-adaptive protocol for 1, 2 and 3 \\textsf{qNLB} copies by constructing a matching dual solution for the associated primal semidefinite program (SDP). We conclude that \\textsf{qNLB}s are a stronger resource for nonlocality than \\textsf{NLB}s. The main premise that develops from this conclusion is that the \\textsf{NLB} model is not the strongest resource to investigate the fundamental principles that limit quantum nonlocality. As such, our work provides strong motivation to reconsider the status quo of the principles that are known to limit nonlocal correlations under the framework of \\textsf{qNLB}s rather than \\textsf{NLB}s.

  2. 7 CFR 51.1270 - Packing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  3. 7 CFR 51.1311 - Packing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  4. 7 CFR 51.1311 - Packing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  5. 7 CFR 51.1270 - Packing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  6. 7 CFR 51.1311 - Packing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  7. 7 CFR 51.1270 - Packing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  8. 7 CFR 51.1311 - Packing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  9. 7 CFR 51.1270 - Packing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  10. 7 CFR 51.1311 - Packing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  11. 7 CFR 51.1270 - Packing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

  12. THE SYMMETRY OF OPTIMALLY DENSE PACKINGS

    E-print Network

    with packings of regular pentagons in the Euclidean plane, E 2 . First we recall that by a ``packing'' pTHE SYMMETRY OF OPTIMALLY DENSE PACKINGS by Charles Radin * Mathematics Department, University was the densest packings of simple bodies, for instance spheres or polyhedra, in Euclidean or hyperbolic spaces

  13. Preprototype Vapor Compression Distillation Subsystem development

    NASA Technical Reports Server (NTRS)

    Thompson, C. D.; Ellis, G. S.; Schubert, F. H.

    1981-01-01

    Vapor Compression Distillation (VCD) has evolved as the most promising approach to reclaim potable water from wastewater for future long-term manned space missions. Life Systems, Inc. (LSI), working with NASA, has developed a preprototype Vapor Compression Distillation Subsystem (VCDS) which processes wastewater at 1.4 kg/h. The preprototype unit weighs 143 kg, occupies a volume of 0.47 cu m, and will reclaim 96 percent of the available wastewater. This unit has been tested by LSI and is scheduled for further testing at NASA-JSC. This paper presents the preprototype VCDS design, configuration, performance data, test results and flight system projections.

  14. Vacuum distillation/vapor filtration water recovery

    NASA Technical Reports Server (NTRS)

    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.

  15. Continuous-flow metal biosorption in a regenerable Sargassum column

    Microsoft Academic Search

    B. Volesky; J. Weber; J. M. Park

    2003-01-01

    Metal biosorption behavior of raw seaweed S. filipendula in ten consecutive sorption–desorption cycles has been investigated in a packed-bed flow-through column during a continuous removal of copper from a 35mg\\/L aqueous solution at pH 5. The elutant used was a 1% (w\\/v) CaCl2\\/HCl-solution at pH 3. The sorption and desorption was carried out for an average of 85 and 15h,

  16. Effects of Residence Time Distribution and Packing on Methanol Oxidation in Biotrickling Filter

    Microsoft Academic Search

    Yuanita W. Hutomo; K. L. Pinder

    2006-01-01

    The effects of residence time distribution (RTD) on biotrickling filter systems and the comparison of the maximum elimination capacity (EC) and poisoning limits as functions of loadings of two packing media, Celite Bio-catalyst Carrier R-635 and a subituminous coal, were studied. To alter the RTD patterns in the two reactor columns, two baffle designs were chosen. The RTD tests were

  17. Axial dispersion in gases flowing through a packed bed at elevated pressures

    Microsoft Academic Search

    A. H. Benneker; A. E. Kronberg; J. W. Post; K. R. Westerterp

    1996-01-01

    Axial dispersion in upward gas flow is investigated by pulse and displacement experiments in a vertical, packed column with different concentrations of the tracer and at pressures up to 1.5 MPa. The responses to the introduced pulse and step changes are measured at two locations and the extent of axial dispersion, respresented by the Bodenstein number, is determined by curve

  18. Reducing CO2 emissions and energy consumption of heat-integrated distillation systems.

    PubMed

    Gadalla, Mamdouh A; Olujic, Zarko; Jansens, Peter J; Jobson, Megan; Smith, Robin

    2005-09-01

    Distillation systems are energy and power intensive processes and contribute significantly to the greenhouse gases emissions (e.g. carbon dioxide). Reducing CO2 emissions is an absolute necessity and expensive challenge to the chemical process industries in orderto meetthe environmental targets as agreed in the Kyoto Protocol. A simple model for the calculation of CO2 emissions from heat-integrated distillation systems is introduced, considering typical process industry utility devices such as boilers, furnaces, and turbines. Furnaces and turbines consume large quantities of fuels to provide electricity and process heats. As a result, they produce considerable amounts of CO2 gas to the atmosphere. Boilers are necessary to supply steam for heating purposes; besides, they are also significant emissions contributors. The model is used in an optimization-based approach to optimize the process conditions of an existing crude oil atmospheric tower in order to reduce its CO2 emissions and energy demands. It is also applied to generate design options to reduce the emissions from a novel internally heat-integrated distillation column (HIDiC). A gas turbine can be integrated with these distillation systems for larger emissions reduction and further energy savings. Results show that existing crude oil installations can save up to 21% in energy and 22% in emissions, when the process conditions are optimized. Additionally, by integrating a gas turbine, the total emissions can be reduced further by 48%. Internal heat-integrated columns can be a good alternative to conventional heat pump and other energy intensive close boiling mixtures separations. Energy savings can reach up to 100% with respect to reboiler heat requirements. Emissions of these configurations are cut down by up to 83%, compared to conventional units, and by 36%, with respect to heat pump alternatives. Importantly, cost savings and more profit are gained in parallel to emissions minimization. PMID:16190250

  19. Heat transfer studies of packed bed coal liquefaction reactors

    SciTech Connect

    Holcombe, N. T.; Knickle, H. N.; Yavorsky, P. M.

    1980-06-01

    The effective thermal conductivity (K/sub e/) and wall heat transfer coefficient (H/sub w/) were determined in a packed bed reactor model over a range of gas mass velocities from 0 to 15,000 kg/m/sup 2/ hr, liquid mass velocities from 5000 to 65,000 kg/m/sup 2/ hr, and pressures that simulate coal liquefaction pressures from 1000 to 4000 psig. A correlation for K/sub e/ and H/sub w/ was developed for the range of study. Several mathematical models for one and two dimensions, and for one and two parameters, were derived to describe two-phase flow in packed beds. Two flow regimes are described. The entrance effects for the low liquid flow regime seem to be limited to a length of about ten diameters, while the entrance effects for the high liquid flow seem to extend through the entire length of the column.

  20. Sleeping distance in wild wolf packs

    USGS Publications Warehouse

    Knick, S.T.; Mech, L.D.

    1980-01-01

    Sleeping distances were observed among members of 13 wild wolf (Canis lupus) packs and 11 pairs in northeastern Minnesota to determine if the distances correlated with pack size and composition. The study utilized aerial radio-tracking and observation during winter. Pack size and number of adults per pack were inversely related to pack average sleeping distance and variability. No correlation between sleeping distance and microclimate was observed. Possible relationships between social bonding and our results are discussed.