Science.gov

Sample records for packed distillation column

  1. Distillation Column Modeling Tools

    SciTech Connect

    2001-09-01

    Advanced Computational and Experimental Techniques will Optimize Distillation Column Operation. Distillation is a low thermal efficiency unit operation that currently consumes 4.8 quadrillion BTUs of energy...

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

    E-print Network

    Hill, J.H.

    1987-01-01

    "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...

  3. Distillation Column Flooding Predictor

    SciTech Connect

    2002-02-01

    This factsheet describes a research project whose goal is to develop the flooding predictor, an advanced process control strategy, into a universally useable tool that will maximize the separation yield of a distillation column.

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

    E-print Network

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

    1986-01-01

    As the need to reduce production costs causes manufacturers to re-evaluate processing schemes, high efficiency structured packings are increasingly recognized as an effective alternative for reducing energy consumption in ...

  5. Distillation Column Flooding Predictor

    SciTech Connect

    George E. Dzyacky

    2010-11-23

    The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillation columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid/vapor traffic that produce increased contact area and lead to substantial increases in separation efficiency – which translates to a 10% increase in energy efficiency on a BTU/bbl basis. The Flooding Predictor™ operates on the principle that between five to sixty minutes in advance of a flooding event, certain column variables experience an oscillation, a pre-flood pattern. The pattern recognition system of the Flooding Predictor™ utilizes the mathematical first derivative of certain column variables to identify the column’s pre-flood pattern(s). This pattern is a very brief, highly repeatable, simultaneous movement among the derivative values of certain column variables. While all column variables experience negligible random noise generated from the natural frequency of the process, subtle pre-flood patterns are revealed among sub-sets of the derivative values of column variables as the column approaches its hydraulic limit. The sub-set of column variables that comprise the pre-flood pattern is identified empirically through in a two-step process. First, 2ndpoint’s proprietary off-line analysis tool is used to mine historical data for pre-flood patterns. Second, the column is flood-tested to fine-tune the pattern recognition for commissioning. Then the Flooding Predictor™ is implemented as closed-loop advanced control strategy on the plant’s distributed control system (DCS), thus automating control of the column at its hydraulic limit.

  6. EXPERIMENTAL SIMULATION OF DISTILLATION COLUMN PROFILE MAPS

    E-print Network

    Skogestad, Sigurd

    EXPERIMENTAL SIMULATION OF DISTILLATION COLUMN PROFILE MAPS Tshepo Sehole David Modise A thesis or in combination, such as distillation, extraction, crystallization, ect. Among these, distillation is by far profiles for the preliminary design of distillation columns. Residue curves and column profile are not only

  7. 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

  8. Tritium Isotope Separation Using Adsorption-Distillation Column

    SciTech Connect

    Fukada, Satoshi

    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.

  9. 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.

  10. Heat Exchanger Technologies for Distillation Columns 

    E-print Network

    Polley, G. T.

    2002-01-01

    stream_source_info ESL-IE-02-04-11.pdf.txt stream_content_type text/plain stream_size 22278 Content-Encoding ISO-8859-1 stream_name ESL-IE-02-04-11.pdf.txt Content-Type text/plain; charset=ISO-8859-1 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...

  11. 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

  12. 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

  13. 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)

  14. 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.

  15. 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

  16. 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

  17. 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…

  18. 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...

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

    E-print Network

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

    1986-01-01

    the assessment of whether a specific operati on is feasible; (2) it can generate efficiency data to verify thermodynamic models; and (3) it can provide a sound basis for the design of the full scale commercial installation. Hundreds of pilot plant tests... 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 plant testing have shown...

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

    SciTech Connect

    Yang, Dali; Orler, Bruce; Tornga, Stephanie; Welch, Cindy

    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.

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

    E-print Network

    Skogestad, Sigurd

    Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad Department integrated distillation columns are used to reduce the energy consumption for separation. The heat inte- grated distillation columns will behave differently than two normal heat integrated distillation column

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

    E-print Network

    Skogestad, Sigurd

    Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad Department integrated distillation columns are used to reduce the energy consumption for separation. The heat inte­ grated distillation columns will behave differently than two normal heat integrated distillation column

  3. 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.

  4. 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.

    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)

  5. 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

  6. 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 system for TAME reactive distillation process using extraction column with water as a solvent. The design distillation column which was optimized to recover methanol and recycle water to the extraction column. Other

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  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. 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 solution of a numerically challenging reactive distillation column with seven steady-states shows. The Dulmage-Mendelsohn decomposition is inconclusive when applied to the steady-state model of distillation

  14. Temperature effects on nano-LC column packing technology.

    PubMed

    Leonardis, Irene; Capriotti, Fabiana; Cappiello, Achille; Famiglini, Giorgio; Palma, Pierangela

    2012-07-01

    We investigated the effect of temperature on the packing procedure of nano-LC columns (up to 50 cm) and on their performance. Several slurries of stationary phase were prepared using different solvent mixtures. Their stability was evaluated at several temperatures: 70°C, 50°C, and room temperature. At the higher temperature (70°C) the suspensions resulted to be stable for a longer time. For each slurry, we compared nano-LC columns packed with ultrasounds at 70°C and at room temperature. All the columns were tested with a standard mixture at 70°C, to reduce the solvent viscosity and the backpressure. Main chromatographic parameters such as the asymmetry factor, As, the reduced plate high, h, pattern in a Van Deemter plot, the total porosity, ?(t), and the permeability, k, were calculated and discussed. One of the nano-LC columns was used to separate a mixture of pesticides in a LC-MS system with an electron ionization LC-MS interface (Direct-EI). From our knowledge, this is the first study on the role of temperature in the efficiency of slurry-packing procedure. PMID:22761136

  15. Tests of isotopic separation efficiency of palladium packed columns

    SciTech Connect

    Heung, L. K.; Staack, G. C.; Klein, J. E.; Jacobs, W. D.

    2008-07-15

    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 presence were tested using an isotope displacement method. A simple computer model was also developed to calculate the number of theoretical separation stages based on the test results. The effects of column diameter, metal foam presence and gas flow rate were identified. (authors)

  16. 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

  17. 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 Abstract Diabatic distillation is a separation process in which heat is transferred on the trays inside savings is through diabatic distillation. Instead of just one heat source (the reboiler) and one heat sink

  18. 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

  19. Evaluation of Dynamic Models of Distillation Columns with Emphasis on the Initial Response

    E-print Network

    Skogestad, Sigurd

    Evaluation of Dynamic Models of Distillation Columns with Emphasis on the Initial Response Bernd for staged high purity distillation based on first principles is developped. The importance of the tray to experimental data. Key Words Distillation dynamics; Initial time constant 1 Introduction Simplified models

  20. Systems For Column-Based Separations, Methods Of Forming Packed Columns, And Methods Of Purifying Sample Components.

    DOEpatents

    Egorov, Oleg B. (Richland, WA); O'Hara, Matthew J. (Richland, WA); Grate, Jay W. (West Richland, WA); Chandler, Darrell P. (Richland, WA); Brockman, Fred J. (Kennewick, WA); Bruckner-Lea, Cynthia J. (Richland, WA)

    2004-08-24

    The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber. In another aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

  1. Systems for column-based separations, methods of forming packed columns, and methods of purifying sample components

    DOEpatents

    Egorov, Oleg B. (Richland, WA); O'Hara, Matthew J. (Richland, WA); Grate, Jay W. (West Richland, WA); Chandler, Darrell P. (Richland, WA); Brockman, Fred J. (Kennewick, WA); Bruckner-Lea, Cynthia J. (Richland, WA)

    2000-01-01

    The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber. In another aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

  2. Systems For Column-Based Separations, Methods Of Forming Packed Columns, And Methods Of Purifying Sample Components

    DOEpatents

    Egorov, Oleg B. (Richland, WA); O'Hara, Matthew J. (Richland, WA); Grate, Jay W. (West Richland, WA); Chandler, Darrell P. (Richland, WA); Brockman, Fred J. (Kennewick, WA); Bruckner-Lea, Cynthia J. (Richland, WA)

    2006-02-21

    The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber. In another aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

  3. Evaluation of Packed Columns in Supercritical Extraction Processes 

    E-print Network

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

    1986-01-01

    increasing the overall mass transfer rate. SFE and conventional extraction systems can have similar values of interfacial tension, and in such cases, this property would be expected to contribute little to the differences in performance of the two systems... of different packings as a function of the solvent velocity. The extraction process involved the separation of the monoglyceride of oleic acid from a mixture of the oleic acid glycerides; a one-inch diameter column was used with an acetone entrainer...

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

    SciTech Connect

    Han, M.; Park, S.

    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.

  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. 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.

  7. 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

  8. 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

  9. The ideal-column concept: applying exergy to distillation

    SciTech Connect

    Kaiser, V.

    1985-08-19

    An ideal model is described to determine minimum energy requirements and perhaps other system parameters. The concept of exergy analysis is used here to formulate an ideal model for distillation, one that will be applicable to real systems, since exergy provides a comparable base for all energy forms. The analysis is used not only for ranking various setups according to overall results, but to provide comparisons for each section of the system. The paper examines binary mixtures, and characterizes distillation.

  10. Integrated Thermal and Hydraulic Analysis of Distillation Columns 

    E-print Network

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

    2002-01-01

    This paper outlines the implementation of column thermal and hydraulic analysis in a simulation environment. The methodology is described using a separations example. Column Thermal Analysis has been discussed in the literature extensively...

  11. 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

  12. 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.

    1985-01-01

    stream_source_info ESL-IE-85-05-08.pdf.txt stream_content_type text/plain stream_size 23054 Content-Encoding ISO-8859-1 stream_name ESL-IE-85-05-08.pdf.txt Content-Type text/plain; charset=ISO-8859-1 DISTILLATION: ENERGY... 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 is addressed for both new...

  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. 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.

  15. Practical Application of Distillation Column Energy Control Systems 

    E-print Network

    Matthews, S. A.

    1980-01-01

    Optimization, Quality Control (Hard Target), Safety (Soft Target), and Feed Forward - Interactive Control. Both a general and a specific example are used. The specific example is an actual ethylene column....

  16. Investigating the Liquid Distribution in a Reactive Distillation Packing Using High Energy X-Ray Tomography

    NASA Astrophysics Data System (ADS)

    Abdullah, J.; Aferka, S.; Crine, M.; Saroha, A. K.; Toye, D.; Marchot, Pierre

    2007-06-01

    Liquid distribution in a 0.1 m diameter column packed with Katapak-SP12 is investigated with a 420 kV X-ray tomograph. The distribution of the various liquid hold up between baskets and corrugated sheets is quantified.

  17. Packed column supercritical fluid chromatography using stainless steel particles and water as a stationary phase.

    PubMed

    Murakami, Jillian N; Thurbide, Kevin B

    2015-09-15

    Stainless steel (SS) particles were demonstrated as a novel useful support for a water stationary phase in packed column supercritical fluid chromatography using a CO2 mobile phase. Separations employed flame ionization detection, and the system was operated over a range of temperatures and pressures. Retention times reproduced well with RSD values of 2.6% or less. Compared to analogous separations employing a water stationary phase coated onto a SS capillary column, the packed column method provided separations that were about 10× faster, with nearly 8-fold larger analyte retention factors, while maintaining good peak shape and comparable column efficiency. Under normal operating conditions, the packed column contains about 131 ± 4 ?L/m of water phase (around a 5% m/m coating), which is over 25× greater than the capillary column and also affords it a 20-fold larger sample capacity. Several applications of the packed column system are examined, and the results indicate that it is a useful alternative to the capillary column mode, particularly where analyte loads or sample matrix interference is a concern. Given its high sample capacity, this packed column method may also be useful to explore on a more preparative scale in the future. PMID:26308256

  18. Black-Box Identification for PLC based MPC of a Binary Distillation Column

    E-print Network

    Black-Box Identification for PLC based MPC of a Binary Distillation Column B. Huyck ,, F. Logist J is to upgrade the control system with a linear MPC running on a PLC. However, before a model based controller can be used on a PLC, an accurate (but simple) process model has to be constructed. Hence, the aim

  19. Performance of columns packed with the new shell particles, Kinetex-C18.

    PubMed

    Gritti, Fabrice; Leonardis, Irene; Shock, David; Stevenson, Paul; Shalliker, Andrew; Guiochon, Georges

    2010-03-01

    The performance of the new Kinetex-C(18) column was investigated. Packed with a new brand of porous shell particles, this column has an outstanding efficiency. Once corrected for the contribution of the instrument extra column volume, the minimum values of the reduced plate heights for a number of low molecular weight compounds (e.g., anthracene and naphtho[2,3-a]pyrene) were between 1.0 and 1.3, breaking the legendary record set 3 years ago by Halo-C(18) packed columns. The liquid-solid mass transfer of proteins (e.g., insulin and lyzozyme) is exceptionally fast on Kinetex-C(18) much faster than on the Halo-C(18) column. The different contributions of dispersion and mass transfer resistances to the column efficiency were determined and discussed. The possible reasons for this extremely high column efficiency are discussed. PMID:20116065

  20. 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

  1. GOBF-ARMA based model predictive control for an ideal reactive distillation column.

    PubMed

    Seban, Lalu; Kirubakaran, V; Roy, B K; Radhakrishnan, T K

    2015-11-01

    This paper discusses the control of an ideal reactive distillation column (RDC) using model predictive control (MPC) based on a combination of deterministic generalized orthonormal basis filter (GOBF) and stochastic autoregressive moving average (ARMA) models. Reactive distillation (RD) integrates reaction and distillation in a single process resulting in process and energy integration promoting green chemistry principles. Improved selectivity of products, increased conversion, better utilization and control of reaction heat, scope for difficult separations and the avoidance of azeotropes are some of the advantages that reactive distillation offers over conventional technique of distillation column after reactor. The introduction of an in situ separation in the reaction zone leads to complex interactions between vapor-liquid equilibrium, mass transfer rates, diffusion and chemical kinetics. RD with its high order and nonlinear dynamics, and multiple steady states is a good candidate for testing and verification of new control schemes. Here a combination of GOBF-ARMA models is used to catch and represent the dynamics of the RDC. This GOBF-ARMA model is then used to design an MPC scheme for the control of product purity of RDC under different operating constraints and conditions. The performance of proposed modeling and control using GOBF-ARMA based MPC is simulated and analyzed. The proposed controller is found to perform satisfactorily for reference tracking and disturbance rejection in RDC. PMID:25956185

  2. 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.

    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)

  3. Colloquium: Geometry and optimal packing of twisted columns and filaments

    NASA Astrophysics Data System (ADS)

    Grason, Gregory M.

    2015-04-01

    This Colloquium presents recent progress in understanding constraints and consequences of close-packing geometry of filamentous or columnar materials possessing nontrivial textures, focusing, in particular, on the common motifs of twisted and toroidal structures. The mathematical framework is presented that relates spacing between linelike, filamentous elements to their backbone orientations, highlighting the explicit connection between the interfilament 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 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 folding of multifilament bundles.

  4. 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

  5. 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.

  6. 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

  7. Graphic exergy analysis of processes in distillation column by energy-utilization diagrams

    SciTech Connect

    Taprap, Ruchira; Ishida, Masaru

    1996-06-01

    The graphical construction called an energy-utilization diagram (EUD) is adopted for analyses of energy transformation and exergy losses in a distillation column. The overall exergy loss on one plate of a column can be decomposed into six kinds of exergy losses and are represented graphically. Two of them are caused by mixing and cooling in the vapor phase, and the other two by mixing and heating in the liquid phase. To display the remaining two yielded by condensation and evaporation of each component, the concept of the individual energy level is applied. The relationship between the individual energy level and the xy diagram is presented as well as effects of the reflux ratio and the feed location on the EUD for the whole column. Separation of n-hexane and n-octane is used to illustrate the methodology.

  8. Exchange front stability in packed-column chromatography

    SciTech Connect

    Griffiths, S.K.; Nilson, R.H.

    1993-04-01

    Exchange front deformation in gas-phase chromatography may sometimes impair column performance. Such deformation can arise from column heterogeneities or from the unstable growth of small disturbances inherently present in the flow field. Here we examine the fundamental stability of a planar traveling exchange front subject to a small sinusoidal perturbation in the front position. The analysis includes the disparity between fluid and front velocities characteristic of exchange chromatography, as well as the distinction between fluid velocities ahead of and behind the front resulting from the net sorption of gases. Fluid compressibility is also considered. Disturbance growth rates are computed as a function of the wavelength, fluid viscosity ratio, and normalized front and fluid velocities over a wide range of each parameter. We find that growth rates increase with increasing viscosity ratio, decreasing wavelength, and increasing normalized front and fluid velocities. Conditions of neutral stability are also determined and indicate that fluid compressibility and net desorption tend to destabilize the exchange front. Sample calculations are presented for the problem of hydrogen isotope exchange in a column of palladium powder.

  9. 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

  10. Continuous aqueous two-phase extraction of human antibodies using a packed column.

    PubMed

    Rosa, P A J; Azevedo, A M; Sommerfeld, S; Bäcker, W; Aires-Barros, M R

    2012-01-01

    The performance of a pilot scale packed differential contactor was evaluated for the continuous counter-current aqueous two-phase extraction (ATPE) of human immunoglobulin G (IgG) from a Chinese hamster ovary (CHO) cells supernatant (CS) enriched with pure protein. Preliminary studies have been firstly performed in order to select the dispersed phase (phosphate-rich or polyethylene glycol 3350 Da (PEG)-rich phase) and the column packing material. The PEG-rich phase has been selected as the dispersed phase and the stainless steel as the preferred material for the column packing bed since it was not wetted preferentially by the selected dispersed phase. Hydrodynamic studies have been also performed, and the experimental results were successfully adjusted to the Richardson-Zaki and Mísek equations, typically used for the conventional organic-aqueous two-phase systems. An experimental set-up combining the packed column with a pump mixer-settler stage showed to have the best performance and to be advantageous when compared to the IgG batch extraction. An IgG recovery yield of 85% could be obtained with about 50% of total contaminants and more than 85% of contaminant proteins removal. Mass transfer studies have revealed that the mass transfer was controlled by the PEG-rich phase. A higher efficiency could be obtained when using an extra pump mixer-settler stage and higher flow rates. PMID:22173005

  11. 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.

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

    PubMed

    Li, Zhaohui; Kirk Jones, H; Zhang, Pengfei; Bowman, Robert S

    2007-08-01

    Chromate transport through columns packed with zeolite/zero valent iron (Z/ZVI) pellets, either untreated or treated with the cationic surfactant hexadecyltrimethylammonium (HDTMA), was studied at different flow rates. In the presence of sorbed HDTMA, the chromate retardation factor increased by a factor of five and the pseudo first-order rate constant for chromate reduction increased by 1.5-5 times. The increase in rate constant from the column studies was comparable to a six-fold increase in the rate constant determined in a batch study. At a fast flow rate, the apparent delay in chromate breakthrough from the HDTMA modified Z/ZVI columns was primarily caused by the increase in chromate reduction rate constant. In contrast, at a slower flow rate, the retardation in chromate transport from the HDTMA modified Z/ZVI columns mainly originated from chromate sorption onto the HDTMA modified Z/ZVI pellets. Due to dual porosity, the presence of immobile water was responsible for the earlier breakthrough of chromate in columns packed with zeolite and Z/ZVI pellets. The results from this study further confirm the role of HDTMA in enhancing sorption and reduction efficiency of contaminants in groundwater remediation. PMID:17448519

  13. 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

  14. Composition Change Characteristics of R407C by a Packed Column Rectifier

    NASA Astrophysics Data System (ADS)

    Okazaki, Takashi; Katoh, Yohei; Obayashi, Tomoyoshi; Hirata, Yushi

    The composition separation of R407C is used to improve performance of air conditioners and heat pump water heater units. Therefore, it is important to grasp a separation performance of a packed column rectifier and make a useful nondimensional equation of mass transfer coefficients for design of the rectifier. The experiments were carried out to investigate an influence of the vapor velocity on the separation performance, and an overall mass transfer coefficient of gas side was measured. The nondimensional equation for the mass transfer coefficients was made based on the measured data. The influence of the refrigerant charge and the packed height on the separation performance was evaluated with the experiments and calculated results with the equation. The calculated results agreed with the experimental results.

  15. 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

  16. 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.

    2015-05-01

    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.

  17. Transport of Viruses Through Saturated and Unsaturated Columns Packed With Sand

    NASA Astrophysics Data System (ADS)

    Anders, R.; Chrysikopoulos, C. V.

    2008-05-01

    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 [2000] to quantify the 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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…

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

    SciTech Connect

    Hideo Usui; Yuichi Niibori; Hitoshi Mimura; Osamu Tochiyama

    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)

  4. Packed-column supercritical fluid chromatography: Quantitative determination of uranium without liquid waste generation

    SciTech Connect

    Martin-Daguet, V.; Gasnier, P.; Caude, M.

    1997-02-01

    A new procedure for the determination of uranium by packed-column supercritical fluid chromatography is proposed. A nonfluorinated chelating agent selective for copper and uranium, the 2,6-diacetylpyridine bis(benzoylhydrazone), has been chosen. We have studied its chromatographic properties on different stationary phases and the influence of the methanol content in the carbon dioxide mobile phase. The separation of the metal compounds was conducted with and without solvent injection. A calibration curve was obtained for uranium in the range of 52-323 ng injected. The accuracy of the method is 0.5%, the repeatability 4%. The same studies were performed with a new compound, diacetyl-2,6 pyridine bis(4-tert-butyl benzoylhydrazone). An increase in retention and efficiency was then observed. 30 refs., 5 figs., 3 tabs.

  5. 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.

  6. 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

  7. Performance of columns packed with the new shell Kinetex-C18 particles in gradient elution chromatography.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2010-03-01

    The performance of columns packed with the new 2.6 microm Kinetex-C(18) shell particles was investigated in gradient elution chromatography and compared with those of the 2.7 microm Halo-C(18) shell particles and the 1.7 microm BEH-C(18) totally porous particles. The peak capacities P(c) of these columns were derived from the resolution of the components of a peptide mixture (beta-Lactoglobulin digest) and of a mixture of two biomolecules (insulin and lyzozyme).The three columns exhibit the same peak capacities for the peptides at low linear velocity (u(0) < 0.05 cm/s) and at any gradient steepness (0.8 < G < 10). When the linear velocity is increased 10-fold, the peak capacity of the Kinetex column remains nearly unchanged while those of the Halo-C(18) and the BEH-C(18) columns decrease by 20%, approximately. This result confirms the very flat HETP curve, the very low C term of the Kinetex column and its ability to successfully operate at high flow rates while experiencing less efficiency loss than other columns. Despite its smaller average mesopore size (96 A versus 130 A), the column packed with 2.6 microm shell Kinetex-C(18) particles gives an equivalent or even slightly better separation of biomolecules having a size and a mass around 40 A and 15 kDa, respectively, than the column packed with 1.7 microm BEH-C(18) totally porous particles. This result demonstrates the advantages of the shell versus the conventional particle technology when it comes to resolve mixtures of large and slow diffusive biomolecules. PMID:20122688

  8. 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

  9. Validating the Equilibrium Stage Model for an Azeotropic System in a Laboratorial Distillation Column

    ERIC Educational Resources Information Center

    Duarte, B. P. M.; Coelho Pinheiro, M. N.; Silva, D. C. M.; Moura, M. J.

    2006-01-01

    The experiment described is an excellent opportunity to apply theoretical concepts of distillation, thermodynamics of mixtures and process simulation at laboratory scale, and simultaneously enhance the ability of students to operate, control and monitor complex units.

  10. 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 ...

  11. An applicable method for efficiency estimation of operating tray distillation columns and its comparison with the methods utilized in HYSYS and Aspen Plus

    NASA Astrophysics Data System (ADS)

    Sadeghifar, Hamidreza

    2015-10-01

    Developing general methods that rely on column data for the efficiency estimation of operating (existing) distillation columns has been overlooked in the literature. Most of the available methods are based on empirical mass transfer and hydraulic relations correlated to laboratory data. Therefore, these methods may not be sufficiently accurate when applied to industrial columns. In this paper, an applicable and accurate method was developed for the efficiency estimation of distillation columns filled with trays. This method can calculate efficiency as well as mass and heat transfer coefficients without using any empirical mass transfer or hydraulic correlations and without the need to estimate operational or hydraulic parameters of the column. E.g., the method does not need to estimate tray interfacial area, which can be its most important advantage over all the available methods. The method can be used for the efficiency prediction of any trays in distillation columns. For the efficiency calculation, the method employs the column data and uses the true rates of the mass and heat transfers occurring inside the operating column. It is highly emphasized that estimating efficiency of an operating column has to be distinguished from that of a column being designed.

  12. 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.

  13. 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.

  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. 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.

  16. Mobility of Dissolved Organic Matter from the Suwannee River (Georgia, USA) in Sand-Packed Columns

    PubMed Central

    McInnis, Daniel P.; Bolster, Diogo; Maurice, Patricia A.

    2015-01-01

    Abstract Transport of dissolved organic matter (DOM) from the Suwannee River and of synthetic polystyrene sulfonates (PSSs) was investigated in columns packed with naturally Fe/Al-oxide-coated sands from Oyster, Virginia. Surface-water samples were collected in May 2012 and processed by XAD-8 (humic substances; HPOA), XAD-4 (transphilic acids [TPIAs]), and reverse osmosis (broad range of components; NOM). Median transport time (Ro) of PSSs increased with molecular weight (MW) from 1,000 to 8,000 Da but decreased for the largest PSS (18,000 Da), which is consistent with previous observations of MW effects on DOM adsorption and transport. Breakthrough curves (BTCs) of HPOAs and NOM were similar whereas TPIA transport was distinct; although all DOM samples had similar Ro values, BTC asymmetry and dispersivity were greater for TPIAs. All samples exhibited power-law tailing that is characteristic of heterogeneous sorbent/sorbate interactions, potentially including kinetic effects. The one-dimensional advection-dispersion equation was unable to capture the tailing but it was captured well using a continuous-time random walk (CTRW) model. CTRW parameters were similar for the NOM and HPOA samples but distinctly different for TPIAs, which had more pronounced tailing. While retardation of organics generally tends to increase with MW, the lower average MW of TPIAs did not result in decreased overall retardation, which suggests the importance of compositional differences. Results suggest that while TPIAs tend to be a relatively minor component of DOM, their transport behavior differs from that of the predominant HPOA fraction, and they might thus have different impacts on pollutant transport. PMID:25565760

  17. 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

    stream_source_info ESL-IE-81-04-17.pdf.txt stream_content_type text/plain stream_size 24668 Content-Encoding ISO-8859-1 stream_name ESL-IE-81-04-17.pdf.txt Content-Type text/plain; charset=ISO-8859-1 ;~ ....~ HIGH... and is rejected in the overheads. This, however, also makes distillation operations energy inefficient, and it comes as no surprise that the majority of a plant's operating cost may be attri buted to it. Development of an effective method for reducing...

  18. Physical properties and structure of fine core-shell particles used as packing materials for chromatography relationships between particle characteristics and column performance

    SciTech Connect

    Gritti, Fabrice; Guiochon, Georges A

    2010-01-01

    The recent development of new brands of packing materials made of fine porous-shell particles, e.g., Halo and Kinetex, has brought great improvements in potential column efficiency, demanding considerable progress in the design of chromatographic instruments. Columns packed with Halo and Kinetex particles provide minimum values of their reduced plate heights of nearly 1.5 and 1.2, respectively. These packing materials have physical properties that set them apart from conventional porous particles. The kinetic performance of 4.6 mm I.D. columns packed with these two new materials is analyzed based on the results of a series of nine independent and complementary experiments: low-temperature nitrogen adsorption (LTNA), scanning electron microscopy (SEM), inverse size-exclusion chromatography (ISEC), Coulter counter particle size distributions, pycnometry, height equivalent to a theoretical plate (HETP), peak parking method (PP), total pore blocking method (TPB), and local electrochemical detection across the column exit section (LED). The results of this work establish links between the physical properties of these superficially porous particles and the excellent kinetic performance of columns packed with them. It clarifies the fundamental origin of the difference in the chromatographic performances of the Halo and the Kinetex columns.

  19. 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.

  20. 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

  1. A simplified mathematical model of the cryogenic distillation with application to the (13C) isotope separation column

    NASA Astrophysics Data System (ADS)

    Neaga, A. O.; Festila, C.; Dulf, E. H.; Both, R.; Szelitzky, T.; Gligan, M.

    2012-02-01

    The isotope (13C) has a widespread application in many fields such as chemistry, physics, medicine, etc. To obtain a high concentration in isotope of interest, in our case (13C), it is used the method of cryogenic distillation of carbon monoxide (CO) which is based on the difference between the vapor pressure of (12C16O) and (13C16O) at the temperature of liquid nitrogen. Isotopic separation plant, used to obtain the isotope (13C), is a complex installation, with many inputs and outputs, rather difficult to control. Due to this reason, from the point of view of automation, it is needed a simplified mathematical model. This model can be determined only with some presumption and simplification assumptions. Using the physical laws, the hydrodynamic part of the process and the mass balance will be described by partial differential equations. In order to design a controller for the column, it is needed a transfer function or a statespace realization of the plant, which is the main contribution of the present work. Implementing this mathematical model will be the key element for describing and understanding the operation of the plant and for future development of process control strategies.

  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. 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

  4. 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.

    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.

  5. Development of Packed Column for Surface Acoustic Wave Gas Chromatograph Using Anodically Bonded Silicon-Glass Structure with a Compression Jacket

    NASA Astrophysics Data System (ADS)

    Yamamoto, Yutaro; Akao, Shingo; Sakuma, Masanori; Kobari, Kentaro; Noguchi, Kazuhiro; Nakaso, Noritaka; Tsuji, Toshihiro; Yamanaka, Kazushi

    2009-07-01

    Gas or liquid chromatographs (GC/LCs) are frequently used for multiple-compound sensing, but they are too large and heavy to be portable. To provide a handy GC/LC, many groups have proposed micro GC/LCs in which large columns are replaced by small micro-electro-mechanical-system (MEMS) columns. However, because of the high packing pressure, a packed MEMS column using an anodically bonded structure has not been realized so far. In this study, we realized such a MEMS column for the first time by introducing a compression jacket to reduce the tensile stress at the silicon-glass boundary. Consequently we succeeded in the separation and detection of lower hydrocarbons using a ball surface acoustic wave sensor.

  6. 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.

  7. Transport of surfactant-facilitated multiwalled carbon nanotube suspensions in columns packed with sized soil particles.

    PubMed

    Lu, Yinying; Yang, Kun; Lin, Daohui

    2014-09-01

    Transport of carbon nanotubes (CNTs) in soil/sediment matrixes can regulate their potential eco-effects and has been however rarely studied. Herein, column experiments were conducted to investigate mobility of CNT suspensions stabilized by dodecylbenzenesulfonic acid sodium salt (SDBS), octyl-phenol-ethoxylate (TX-100) and cetylpyridinium chloride (CPC) in four soil samples with certain particle sizes. Humic acid was extracted from a soil sample and was coated on quartz sands to explore the effect of soil organic matter (SOM) on the mobility. Results showed that the positively-charged CPC-CNT was entirely retained in the columns while the negatively-charged SDBS-CNT and TX-100-CNT more or less broke through the columns. Pearson correlation analyses revealed that soil texture rather than SOM controlled the mobility. Electrostatic attraction to and/or precipitation on the grain surfaces together with the straining effect could explain the CNT retention. These novel results will help to understand the eco-effects of CNTs. PMID:24880534

  8. 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).

  9. 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

  10. Relative Transport Behavior of Escherichia coli O157:H7 and Salmonella enterica serovar Pullorum in Packed Bed Column Systems: Influence of Solution Chemistry and Cell Concentration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of solution chemistry and cell concentration on bacterial pathogen transport has been examined using Salmonella pullorum and Escherichia coli O157:H7. A packed bed column was employed to determine the transport behavior and deposition kinetics on real aquifer sand particles over a ran...

  11. Catalytic distillation structure

    DOEpatents

    Smith, L.A. Jr.

    1984-04-17

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

  12. Calcium nitrate miscible displacement at different concentrations in packed soil columns

    NASA Astrophysics Data System (ADS)

    Previatello da Silva, Livia; Alves de Oliveira, Luciano; Honorio de Miranda, Jarbas

    2015-04-01

    Studies on miscible displacement provide us with rational means to understand the important physical phenomena involved leaching in soils, fertilizers, movement of ions and other similar processes. With current environmental concerns and the need to understand the processes that govern movement of water and solutes in soil, studies are needed to allow increasing the efficiency of input use in agriculture that somehow can mitigate the impact of activities of this sector on groundwater contamination. Contamination of soil and groundwater and surface water in areas with fertilizer application and reuse of effluent is closely linked to materials chemical characteristics, and retention and transmission of water and soil solutes. Solute mobility in soil is inversely related to their adsorption to solid fraction or to environmental conditions that favor ions precipitation. Ion adsorption to soil exchange complex makes ion maintains exchange with the soil solution, providing once their retention by the solid fraction, another its availability in aqueous medium. Nitrate leaching is a physical phenomenon, favored by low energy involved in adsorption to soil particles and also by its high solubility in water. This high solubility and the weak interaction with soil matrix to allow anion follow the wetting front. Therefore, the objective was determine nitrate transport parameters in soil, through Breakthrough Curves (BTC) development under conditions of disturbed soil samples (saturated soil and steady state conditions) in columns (20.0 cm in height and 5 cm in diameter), by calcium nitrate solution application at two concentrations, 50 and 130 g m-3 NO3-, in two tropical soil types, Yellow Oxisol (S1) and Anfisol (S2). Research was carried out in laboratory. Transport parameters for both soils and nitrate concentrations were obtained by numerical fit using STANMOD software, by the inverse modelling. Results showed predominance of convective transport in S1, which had a higher Peclet number (P) at concentration 50 g m-3. There was no difference in the others parameters due to different nitrate concentrations. It was observed a higher nitrate leaching on S1.

  13. Quantitative analysis of transverse bacterial migration induced by chemotaxis in a packed column with structured physical heterogeneity.

    PubMed

    Wang, Meng; Ford, Roseanne M

    2010-01-15

    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. On the basis of parameter sensitivity analysis, 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

  14. Phenol Biodegradation by Free and Immobilized Candida tropicalis RETL-Crl on Coconut Husk and Loofah Packed in Biofilter Column

    NASA Astrophysics Data System (ADS)

    Shazryenna, D.; Ruzanna, R.; Jessica, M. S.; Piakong, M. T.

    2015-04-01

    Phenols and its derivatives are environmental pollutant commonly found in many industrial effluents. It is toxic in nature and causes various health hazards. However, they are poorly removed in conventional biological processes due to their toxicity. Immobilization of microbial cells has received increasing interest in the field of waste treatment and creates opportunities in a wide range of sectors including environmental pollution control. Live cells of phenol-degrading yeast, Candida tropicalis RETL-Crl, were immobilized on coconut husk and loofah by adsorption. The immobolized particle was packed into biofilter column which used for continuous treatment of a phenol with initial phenol concentration of 3mM. Both loofah and coconut husk have similar phenol biodegradation rate of 0.0188 gL-1h-1 within 15 hours to achieve a phenol removal efficiency of 100%. However loofah have lower biomass concentration of 4.22 gL-1 compared to biomass concentration on coconut husk, 4.39 gL-1. Coconut husk contain higher biomass concentration which makes it better support material than loofah. Fibrous matrices such as loofah and coconut husk provide adequate supporting surfaces for cell adsorption, due to their high specific surface area. Therefore, coconut husk and loofah being an agricultural waste product have the potential to be used as low-cost adsorbent and support matrix for microbial culture immobilization for the removal of organic pollutant from wastewater.

  15. Efficient control system for low-concentration inorganic gases from a process vent stream: application of surfactants in spray and packed columns.

    PubMed

    Chein, Hungmin; Aggarwal, Shankar G; Wu, Hsin-Hsien

    2004-11-01

    Control of low-concentration pollutants from a semiconductor process vent stream using a wet-scrubbing technique is a challenging task to meet Taiwan environmental emission standards. An efficient wet-scrubber is designed on a pilot scale and tested to control low concentration acid and base waste-gas emission. The scrubber system consisted of two columns, i.e., a fine spray column [cutoff diameter (based on volume), Dv(50) = 15.63 microm; Sauter mean diameter (SMD) = 7.62 microm], which is especially efficient for NH3 removal as the pH of the spraying liquid is approximately 7 followed by a packed column with a scrubbing liquid pH approximately 9.0 mainly for acids removal. It is observed that use of the surfactants in low concentration about 10(-4) M and 10(-7) M in the spray liquid and in the scrubbing liquid, respectively, remarkably enhances the removal efficiency of the system. A traditional packed column (without the spray column and the surfactant) showed that the removal efficiencies of NH3, HF, and HCl for the inlet concentration range 0.2 to 3 ppm were (n = 5) 22.6+/-3.4%, 43.4+/-5.5%, and 40.4+/-7.4%, respectively. The overall efficiencies of the proposed system (the spray column and the packed column) in the presence of the surfactant in the spray liquid and in the scrubbing liquid forthese three species were found to increase significantly (n = 5) from 60.3+/-3.6 to 82.8+/-6.8%, 59.1+/-2.7 to 83.4+/-4.2%, and 56.2+/-7.3 to 81.0+/-6.7%, respectively. In this work, development of charge on the gas-liquid interface due to the surfactants has been measured and discussed. It is concluded that the presence of charge on the gas-liquid interface is the responsible factor for enhancement of the removal efficiency (mass-transfer in liquid phase). The effects of the type of surfactants, their chain length, concentration in liquid, etc. on the removal efficiency are discussed. Since the pilot tests were performed under the operating conditions similar to most of the wet-scrubbers operated in semiconductors manufacturing facilities for inorganic pollutants, this study can be applied to modify the existing wet-scrubbers to enhance the removal efficiencies, especially for low-concentration pollutants. PMID:15575298

  16. Transport behavior of humic acid-modified nano-hydroxyapatite in saturated packed column: effects of Cu, ionic strength, and ionic composition.

    PubMed

    Wang, Dengjun; Chu, Lingyang; Paradelo, Marcos; Peijnenburg, Willie J G M; Wang, Yujun; Zhou, Dongmei

    2011-08-15

    The surfaces of nano-hydroxyapatite (nHAP) used for contaminated soil and groundwater remediation may be modified to render nHAP highly mobile in the subsurface. Humic acid (HA) is widely used to modify and stabilize colloid suspensions. In this work, column experiments were conducted to determine the effects of contaminant (e.g., Cu) concentration, ionic strength (IS), and ion composition (IC) on the transport behavior of HA-modified nHAP in saturated packed columns. IS and nature of the cation had strong effects on the deposition of nHAP, and the effect was greater for divalent than for monovalent cations. Divalent cations have a greater capacity to screen the surface charge of nHAP, and Ca(2+) bridges the HA-modified nHAP colloidal particles, which causes greater deposition. Moreover, Cu(2+) had a greater effect on the transport behavior than Ca(2+) due to their strong exchange with Ca(2+) of nHAP and its surface complexation with nHAP. The relative travel distance L(T), of the injected HA-modified nHAP colloids, ranges from less than one to several meters at varying Cu concentrations, ISs, and ICs in saturated packed columns. The results are crucial to evaluate the efficacy of nHAP on the remediation of contaminated soil and groundwater environments. PMID:21612786

  17. Reliability of computer-assisted method transfer between several column dimensions packed with 1.3-5?m core-shell particles and between various instruments.

    PubMed

    Kormány, Róbert; Fekete, Jen?; Guillarme, Davy; Fekete, Szabolcs

    2014-06-01

    In this contribution, the possibility to automatically transfer RPLC methods between different column dimensions and instruments was evaluated using commercial modelling software. The method transfer reliability was tested with loratadine and its 7 related pharmacopeial impurities. In this study, state-of-the-art columns packed with superficially porous particles of 5, 2.6, 1.7 and 1.3?m particles were exclusively employed. A fast baseline separation of loratadine and related impurities (Rs,min=2.49) was achieved under the best analytical conditions (i.e. column of 50mm×2.1mm, 1.3?m, 10-90% ACN in 5min, T=40°C, pH=3, F=0.5ml/min). This optimal method was successfully tested on columns packed with other particle sizes, namely 1.7 and 2.6?m, to reduce pressure drop. The selectivities and retentions remained identical, while the peak widths were logically wider, leading to a reduction of peak capacity from 203 to 181 and 159 on the 1.3, 1.7 and 2.6?m particles, respectively. On the minimum, the resolution was equal to 1.54 on the 50mm×2.1mm, 2.6?m stationary phase. Next to this, the method was transferred to columns of different lengths, inner diameters and particle sizes (100mm×3mm, 2.6?m or 150mm×4.6mm, 5?m). These columns were used on other LC instruments possessing larger dwell volumes. The modelling software employed for developing the original method was able to calculate the new gradient conditions to be used. The accuracy of prediction was excellent, as the average retention time errors between predicted and observed chromatograms were -0.11% and 0.45% when transferring the method to 100mm×3mm and 150mm×4.6mm columns, respectively. This work proves the usefulness and validity of HPLC modelling software for transferring methods between different instruments, column dimensions and/or flow rates. PMID:24603352

  18. Cryogenic distillation facility for isotopic purification of protium and deuterium.

    PubMed

    Alekseev, I; Arkhipov, Ev; Bondarenko, S; Fedorchenko, O; Ganzha, V; Ivshin, K; Kammel, P; Kravtsov, P; Petitjean, C; Trofimov, V; Vasilyev, A; Vasyanina, T; Vorobyov, A; Vznuzdaev, M

    2015-12-01

    Isotopic purification of the protium and deuterium is an important requirement of many physics experiments. A cryogenic facility for high-efficiency separation of hydrogen isotopes with a cryogenic distillation column as the main element is described. The instrument is portable, so that it can be used at the experimental site. It was designed and built at the Petersburg Nuclear Physics Institute, Gatchina, Russia. Fundamental operating parameters have been measured including a liquid holdup in the column packing, the pressure drops across the column and the purity of the product at different operating modes. A mathematical model describes expected profiles of hydrogen isotope concentration along the distillation column. An analysis of ortho-parahydrogen isomeric composition by gas chromatography was used for evaluation of the column performance during the tuning operations. The protium content during deuterium purification (?100 ppb) was measured using gas chromatography with accumulation of the protium in the distillation column. A high precision isotopic measurement at the Institute of Particle Physics, ETH-Zurich, Switzerland, provided an upper bound of the deuterium content in protium (?6 ppb), which exceeds all commercially available products. PMID:26724068

  19. GraSPI (Graphical Structured Packing Interface)

    Energy Science and Technology Software Center (ESTSC)

    2004-06-10

    GraSPI is a collection of macros (computer programs) written to work in concert with Fluent Inc. software GAMBIT and FLUENT for modeling and design of structured packing columns used in the chemical industry (the application focus is in distillation but other applications such as gas absorbers, and other chemical contactors can also be analyzed). GraSPI is an accessory to GAMBIT and FLUENT that drives the process of complex geometry creation, domain setup, and mesh generation.more »In addition, GraSPI manages automatic flow analysis in the aforementioned domain via either serial or parallel computing using FLUENT. A library of typical commercial structured packing elements is included in GraSPI, so is the capability for user-defined creation of new packings.« less

  20. Ultrahigh-pressure reversed-phase capillary liquid chromatography: isocratic and gradient elution using columns packed with 1.0-micron particles.

    PubMed

    MacNair, J E; Patel, K D; Jorgenson, J W

    1999-02-01

    Fused-silica capillaries with inner diameters of 33 microns and lengths of 25-50 cm are slurry-packed with 1.0-micron nonporous octadecylsilane-modified (C18) silica spheres. These columns are used to perform ultrahigh-pressure reversed-phase liquid chromatographic analyses in both isocratic and gradient elution modes. Mobile-phase pressures as high as 5000 bar (72,000 psi) are applied to column inlets to generate more than 200,000 theoretical plates in 6 min (k' approximately 1) for small, organic analytes. Average capacity factors of analytes are found to increase linearly with applied pressure. An electrically driven constant-flow syringe pump capable of generating mobile-phase pressures as high as 9000 bar (130,000 psi) is described. This pump is used in conjunction with an exponential dilution method for the gradient separation of peptides from a tryptic digest on a 27-cm-long capillary packed with 1.0-micron particles. A peak capacity of 300 is demonstrated for a 30-min analysis. PMID:9989386

  1. 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

  2. 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

  3. Catalytic distillation extends its reach

    SciTech Connect

    Rock, K.; McGuirk, T.; Gildert, G.R.

    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.

  4. Investigation related to hydrogen isotopes separation by cryogenic distillation

    SciTech Connect

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

    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)

  5. 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.

  6. Polyhedra and Packings

    NASA Astrophysics Data System (ADS)

    Steurer, Walter; Deloudi, Sofia

    A packing is an arrangement of non-interpenetrable objects touching each other. In crystallography, dense packings play a special role for crystal structure modeling. Depending on the structure, it may be useful to describe it as packing of atoms or of larger structural units such as chains, columns, bands, layers or polyhedra. In this chapter, we will focus on polyhedra and their ways of space-filling packing. The emphasis is on periodic packings of Platonic and Archimedean solids. Quasiperiodic packings will be discussed on the example of polyhedra with icosahedral symmetry, in particular of triacontahedra and its related zonohedra.

  7. 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

  8. 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

  9. 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

  10. 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

  11. A Comprehensive Real-World Distillation Experiment

    ERIC Educational Resources Information Center

    Kazameas, Christos G.; Keller, Kaitlin N.; Luyben, William L.

    2015-01-01

    Most undergraduate mass transfer and separation courses cover the design of distillation columns, and many undergraduate laboratories have distillation experiments. In many cases, the treatment is restricted to simple column configurations and simplifying assumptions are made so as to convey only the basic concepts. In industry, the analysis of a…

  12. Evaluation of monolithic and sub 2 microm particle packed columns for the rapid screening for illicit drugs--application to the determination of drug contamination on Irish euro banknotes.

    PubMed

    Bones, Jonathan; Macka, Mirek; Paull, Brett

    2007-03-01

    A study comparing recently available 100 x 3 mm id, 200 x 3 mm id monolithic reversed-phase columns with a 50 x 2.1 mm id, 1.8 microm particle packed reversed-phase columns was carried out to determine the most efficient approach (using traditional van Deemter analysis and a modern kinetic plot approach) for the rapid screening of samples for 16 illicit drugs and associated metabolites. A plot of column backpressure versus plate number (N) showed a significant advantage of using the monolithic phases, with the 20 cm monolithic column exhibiting a maximum 15,000 plates at a column backpressure of approximately 70 bar, compared to approximately 7000 plates at 150 bar for the 5 cm 1.8 microm particle packed column. Optimum linear velocities were found to be 0.40 mm s(-1), 0.52 mm s(-1) and 0.98 mm s(-1) for the three above columns, respectively. The 20 cm monolithic column was subsequently applied to the separation and determination of illicit drug contamination on Irish euro banknotes, using methanol extraction followed by LC-MS/MS. Method performance data showed that the new LC-MS/MS method was significantly more sensitive than previous GC-MS/MS based methods for this application, with detection limits in the pg note(-1) region, based upon a 20 microL standard injection. All of the notes examined tested positive for trace quantities of cocaine, with benzoylecgonine detected on 12 of the 45 notes sampled. Traces of heroin were also detected on three of the 45 notes. PMID:17325753

  13. Design of processes with reactive distillation line diagrams

    SciTech Connect

    Bessling, B.; Schembecker, G.; Simmrock, K.H.

    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.

  14. Analysis of F2-isoprostanes in plasma of pregnant women by HPLC-MS/MS using a column packed with core-shell particles

    PubMed Central

    Larose, Jessica; Julien, Pierre; Bilodeau, Jean-François

    2013-01-01

    Plasma F2-isoprostanes (F2-isoPs) are reliable biomarkers of oxidative stress. Several possible F2-isoPs are generated by the oxidation of arachidonic acid esterified in phospholipids. The separation of these isomers represents a technical challenge for rapid and selective determination. We have developed a HPLC-MS/MS method for the simultaneous determination of seven plasma F2-isoPs, namely 8-iso-15(R)-prostaglandin F2? (PGF2?), 8-iso-PGF2?, 15(R)-PGF2?, iPF2?-IV, iPF2?-VI, 5-iPF2?-VI, and (±)5-8,12-iso-iPF2?-VI. We have validated this method in plasma of pregnant women, a mild physiological oxidative stress known to increase F2-isoPs. Thus, plasma samples of women collected at the third trimester of pregnancy (n = 20) were subjected to alkaline hydrolysis followed by liquid-liquid extraction in order to extract total F2-isoPs. The F2-isoPs were separated within 16.5 min using a column packed with core-shell particles. The class VI isomers were the most abundant, accounting for 65% of the total level of all quantified F2-isoPs in plasma of pregnant women (P < 0.05). The 15(R)-PGF2? was the most abundant of the class III isomers quantified. This method allowed fast and selective separation of seven isomers from three different classes of F2-isoP regioisomers. PMID:23431046

  15. 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

  16. 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

  17. 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

  18. 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

  19. Digital distillation the easy way

    SciTech Connect

    Basta, N.

    1995-10-01

    Designing distillation columns may well be the most common problem for chemical engineers. For decades, engineering students have grunted through the iterations of McCabe-Thiele diagrams; working engineers regularly cast a critical eye at column efficiencies and maintenance requirements in their plants. The design and optimization of distillation columns is a problem that has been adapted smoothly to computerization, especially on personal computers. The extensive need for accurate equilibrium and thermodynamics data is tailormade for digital storage. The iterative nature of the design process is also a common element of programming algorithms. Most of the programs on the market feature at least three components: a library of commercially available databases of fluid properties; a distillation or separations engine, using one or several design methods; and algorithms for generating physical-property data synthetically. This paper describes many of the programs on the market for this purpose.

  20. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Distilled spirits, wines, and malt liquors in bulk...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines... conveying imported distilled spirits, wines, and malt liquors, in accordance with 19 U.S.C. 467. (b)...

  1. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Distilled spirits, wines, and malt liquors in bulk...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines... conveying imported distilled spirits, wines, and malt liquors, in accordance with 19 U.S.C. 467. (b)...

  2. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Distilled spirits, wines, and malt liquors in bulk...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines... conveying imported distilled spirits, wines, and malt liquors, in accordance with 19 U.S.C. 467. (b)...

  3. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Distilled spirits, wines, and malt liquors in bulk...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines... conveying imported distilled spirits, wines, and malt liquors, in accordance with 19 U.S.C. 467. (b)...

  4. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Distilled spirits, wines, and malt liquors in bulk...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines... conveying imported distilled spirits, wines, and malt liquors, in accordance with 19 U.S.C. 467. (b)...

  5. Active Constraint Regions for Optimal Operation of Distillation Magnus G. Jacobsen and Sigurd Skogestad*

    E-print Network

    Skogestad, Sigurd

    Active Constraint Regions for Optimal Operation of Distillation Columns Magnus G. Jacobsen, NTNU, N-7491, Trondheim, Norway ABSTRACT: When designing the control structure of distillation columns presented in an earlier paper, to find how the active constraints for distillation columns change

  6. Automated Quantitative Phosphopeptide Enrichment using Titania-packed Capillary Columns and Its Application to Human Tissues for Label-Free Phosphoproteomics

    E-print Network

    Richardson, David

    . For this reason, there has been a rapid increase in the used of TiO2 materials to enrich for phosphorylated species. o Our laboratory previously developed a enrichment protocol using TiO2 particles in a spin column, 83( 10), 3758-3764. Evaluation of TiO2 materials and Capillary Column Enrichment Application

  7. 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.

  8. 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

  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. SIMULATION BASED OPTIMIZATION OF A DIABATIC DISTILLATION Edward Steven Jimenez and Peter Salamon

    E-print Network

    Salamon, Peter

    SIMULATION BASED OPTIMIZATION OF A DIABATIC DISTILLATION COLUMN Edward Steven Jimenez and Peter distillation is a separation process in which heat is transferred inside the column as opposed to classical of this technology on the chemical and process industry is enormous since distillation is the single largest energy

  13. 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

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

    E-print Network

    Skogestad, Sigurd

    Control strategies for reactive batch distillation Eva Swensen and Sigurd Skogestad" Department be combined directly with a distillation column by distilling off the light component product in order a maximum value in order to avoid break-through of an intermediate component in the distillate. This maximum

  15. 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.

  16. 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.

  17. Integrated process of distillation with side reactors for synthesis of organic acid esters

    DOEpatents

    Panchal, Chandrakant B; Prindle, John C; Kolah, Aspri; Miller, Dennis J; Lira, Carl T

    2015-11-04

    An integrated process and system for synthesis of organic-acid esters is provided. The method of synthesizing combines reaction and distillation where an organic acid and alcohol composition are passed through a distillation chamber having a plurality of zones. Side reactors are used for drawing off portions of the composition and then recycling them to the distillation column for further purification. Water is removed from a pre-reactor prior to insertion into the distillation column. An integrated heat integration system is contained within the distillation column for further purification and optimizing efficiency in the obtaining of the final product.

  18. 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

  19. Selective extraction and analysis of catecholamines in rat blood microdialysate by polymeric ionic liquid-diphenylboric acid-packed capillary column and fast separation in high-performance liquid chromatography-electrochemical detector.

    PubMed

    Zhou, Xinguang; Zhu, Anwei; Shi, Guoyue

    2015-08-28

    Concentration of blood catecholamines (CAs) is linked to a host of cardiovascular diseases, including hypertension and stenocardia. The matrix interferences and low concentration require tedious sample pretreatment methods before quantitative analysis by the gold standard method of high-performance liquid chromatography-electrochemical detector (HPLC-ECD). Solid phase extraction (SPE) has been widely used as the pretreatment technique. Here, a facile polymeric ionic liquid (PIL)-diphenylboric acid (DPBA)-packed capillary column was prepared to selectively extract dopamine (DA), noradrenaline (NE) and epinephrine (E) prior to their quantitative analysis by a fast separation in HPLC-ECD method, while microdialysis sampling method was applied to get the analysis sample. Parameters that influenced desorption efficiency, such as pH, salt concentration, acetonitrile content and wash time, were examined and optimized. The proposed method, combining microdialysis sampling technique, SPE and HPLC-ECD system, was successfully applied to detect CAs in rat blood microdialysate with high sensitivity and selectivity in small sample volumes (5-40?l) and a short analysis time (8min), yielding good reproducibility (RSD 6.5-7.7%) and spiked recovery (91-104.4%). PMID:26206631

  20. 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

  1. 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...

  2. Conversion of carboxylate salts to carboxylic acids via reactive distillation 

    E-print Network

    Williamson, Shelly Ann

    2000-01-01

    carboxylate salts are concentrated and reacted with a low-molecular-weight tertiary amine and carbon dioxide to precipitate calcium carbonate. In a distillation column, the low-molecular-weight amine carboxylate reacts with a high-molecular-weight tertiary...

  3. 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)

  4. 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…

  5. DYNAMIC MODELING AND CONTROL OF REACTIVE DISTILLATION FOR HYDROGENATION OF BENZENE 

    E-print Network

    Aluko, Obanifemi

    2010-01-16

    This work presents a modeling and control study of a reactive distillation column used for hydrogenation of benzene. A steady state and a dynamic model have been developed to investigate control structures for the column. ...

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

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

    SciTech Connect

    Sazonov, A.B.; Kagramanov, Z.G.; Magomedbekov, E.P.

    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.

  14. Group methods for advanced column control compared

    SciTech Connect

    Haskins, D.E.; Chauvin, L.; Tolfo, F.

    1985-05-01

    Group method calculations are suited for distillation column advanced controls in real time. Five calculation methods are discussed and compared for accuracy by computing the internal reflux for several columns and operating conditions. Practical design criteria are defined and illustrated by comparing two distillation column reflex control schemes. The resulting conclusions include the best location and preferred order of group method calculations. Because group methods are simpler than stage-to-stage or successive approximation methods, they are more suitable to online computer calculations. Group methods are considered accurate enough for control purposes.

  15. Multipartite nonlocality distillation

    SciTech Connect

    Hsu, Li-Yi; Wu, Keng-Shuo

    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.

  16. 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.

  17. 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.

  18. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, E.M. Jr.

    1985-08-20

    A method and apparatus are disclosed 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. 7 figs.

  19. 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.

  20. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, E.M. Jr.

    1984-03-27

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

  1. 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

  2. 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.

  3. Distill, Distill_human Distill: protein structure prediction by Machine Learning

    E-print Network

    Pollastri, Gianluca

    Distill, Distill_human Distill: protein structure prediction by Machine Learning C. Mirabello1, G.pollastri@ucd.ie Distill has two main components: a set of predictors of protein features based on machine learning" of PDB structures suggested by our fold recognition algorithm. The only difference between Distill

  4. Cryogenic hydrogen isotope distillation for the fusion fuel cycle

    SciTech Connect

    Sherman, R.H.

    1985-01-01

    Cryogenic distillation is an attractive method for the hydrogen isotopic separations required in fusion fuel cycles. The theoretical and practical aspects of designing and constructing such systems are well established. Practical considerations in the design of systems are presented and applied to the Isotope Separation System (ISS) at the Tritium Systems Test Assembly (TSTA), as well as systems of distillation columns that might be used for a reactor such as the Tokamak Fusion Core Experiment (TFCX) and the recovery of breeding blanket product.

  5. Comparison of column flotation cells

    SciTech Connect

    Honaker, R.Q.; Mohanty, M.K.; Ho, K.

    1995-08-01

    Six commercial column flotation technologies, i.e., Canadian, Flotaire, Jameson, Microcel, Packed-Column, and Turbo-air, were tested for the treatment of Illinois Basin fine coal and the results from each column compared based on separation performance and throughout capacity. The separation performance achieved by each cell approached and, in some cases, exceeded the ultimate performance predicted by release analysis. A comparison of the test results indicates differences in the selectivity obtained by each flotation column on the basis of both ash and sulfur rejection. This finding may be due to variations in cell hydrodynamics and the ability to support a deep froth phase among the different column cells. In addition, throughput capacity of each cell was found to differ, apparently due to the differences in the bubble-particle attachment environment, bubble size, and bubble population. Variations in the operating characteristics, such as reagent additions, aeration rate and wash water rate, were also noted and summarized in this publication.

  6. 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.

  7. Intermediate Vapor Expansion Distillation and Nested Enrichment Cascade Distillation 

    E-print Network

    Erickson, D. C.

    1986-01-01

    EXPANSION DISTILLATION AND NESTED ENRICHMENT CASCADE DISTILLATION D.. C. Erickson Energy Concepts Company Annapolis, Maryland ABSTRACT Although it is known that incorporating an intermediate reboiler or reflux condenser in a distillation ~olumn..., the expander is more efficient and less costly than the compressor which achieves comparable improvement in distillation efficiency. With the "nested enrichment" technique, the increased efficiency is obtained without requiring either compressors...

  8. Post column derivatisation analyses review. Is post-column derivatisation incompatible with modern HPLC columns?

    PubMed

    Jones, Andrew; Pravadali-Cekic, Sercan; Dennis, Gary R; Shalliker, R Andrew

    2015-08-19

    Post Column derivatisation (PCD) coupled with high performance liquid chromatography or ultra-high performance liquid chromatography is a powerful tool in the modern analytical laboratory, or at least it should be. One drawback with PCD techniques is the extra post-column dead volume due to reaction coils used to enable adequate reaction time and the mixing of reagents which causes peak broadening, hence a loss of separation power. This loss of efficiency is counter-productive to modern HPLC technologies, -such as UHPLC. We reviewed 87 PCD methods published from 2009 to 2014. We restricted our review to methods published between 2009 and 2014, because we were interested in the uptake of PCD methods in UHPLC environments. Our review focused on a range of system parameters including: column dimensions, stationary phase and particle size, as well as the geometry of the reaction loop. The most commonly used column in the methods investigated was not in fact a modern UHPLC version with sub-2-micron, (or even sub-3-micron) particles, but rather, work-house columns, such as, 250 × 4.6 mm i.d. columns packed with 5 ?m C18 particles. Reaction loops were varied, even within the same type of analysis, but the majority of methods employed loop systems with volumes greater than 500 ?L. A second part of this review illustrated briefly the effect of dead volume on column performance. The experiment evaluated the change in resolution and separation efficiency of some weak to moderately retained solutes on a 250 × 4.6 mm i.d. column packed with 5 ?m particles. The data showed that reaction loops beyond 100 ?L resulted in a very serious loss of performance. Our study concluded that practitioners of PCD methods largely avoid the use of UHPLC-type column formats, so yes, very much, PCD is incompatible with the modern HPLC column. PMID:26343427

  9. Energy conservation in distillation

    NASA Astrophysics Data System (ADS)

    Mix, T. W.; Dweck, J. S.; Weinberg, M.; Armstrong, R. C.

    1981-07-01

    An audit of major industrial and processes and key colums in each major process indicated that approximately twoquads of energy were consumed for distillation in the US in 1976. Energy usage by industry is included: petroleum refineries, 66% chemical (including petrochemical) industry, 29% natural gas liquids processing, 5%. Techniques and current practices for conserving distillation energy are reviewed, and guidelines indicating those process conditons which favor the use of each energy conserving technique are enumerated. Expressions for payout time for tray and control retrofit options are developed based on energy savings and increased throughput. Calculations for industrial colums suggested that both types of retrofits would frequently have short (,6 months) payout times based on either criterion. Extractive distillation is also discussed, and criteria enabling the estimation of the energy which may be conserved using this technique are developed. Good housekeeping practices and field techniques for checking the energy efficiency of industrial distillations are also discussed.

  10. 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)

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Self-regenerating column chromatography

    SciTech Connect

    Park, Woo K.

    1994-12-31

    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 alternation 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 multifunction 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 multifunction ion exchange process is the self-regeneration of the resins. Applications are to separation of nitrogen and sulfur isotopes.

  3. 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 ...

  4. Data acquisition, distillation,Data acquisition, distillation, and storageand storage

    E-print Network

    Quality Control Short term `correctness' ofShort term `correctness' of observationobservation Monitor long term changes ofMonitor long term changes of observatoryobservatory Science Software RequirementsData acquisition, distillation,Data acquisition, distillation, and storageand storage · FASR

  5. Pressure drop in CIM disk monolithic columns.

    PubMed

    Mihelic, Igor; Nemec, Damjan; Podgornik, Ales; Koloini, Tine

    2005-02-11

    Pressure drop analysis in commercial CIM disk monolithic columns is presented. Experimental measurements of pressure drop are compared to hydrodynamic models usually employed for prediction of pressure drop in packed beds, e.g. free surface model and capillary model applying hydraulic radius concept. However, the comparison between pressure drop in monolith and adequate packed bed give unexpected results. Pressure drop in a CIM disk monolithic column is approximately 50% lower than in an adequate packed bed of spheres having the same hydraulic radius as CIM disk monolith; meaning they both have the same porosity and the same specific surface area. This phenomenon seems to be a consequence of the monolithic porous structure which is quite different in terms of the pore size distribution and parallel pore nonuniformity compared to the one in conventional packed beds. The number of self-similar levels for the CIM monoliths was estimated to be between 1.03 and 2.75. PMID:15782951

  6. 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.

  7. Distillation: The Efficient Workhorse 

    E-print Network

    Steinmeyer, D.

    1985-01-01

    stream_source_info ESL-IE-85-05-26.pdf.txt stream_content_type text/plain stream_size 15978 Content-Encoding ISO-8859-1 stream_name ESL-IE-85-05-26.pdf.txt Content-Type text/plain; charset=ISO-8859-1 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...

  8. An artificial intelligence method for the synthesis of heat-integrated distillation flowsheets

    SciTech Connect

    Fang-Yu Han; Ben-Guang Rong

    1996-12-31

    In this paper, a concept of Heat-Integrated Distillation Flowsheet (HIDF) is proposed. It refers to the multicomponent separation flowsheet which is composed of simple and complex columns and in which heat integration is considered so as to achieve minimum energy consumption. The HIDF is very different from the Heat-Integrated Distillation Sequences (HIDS) in the literature which only consists of simple columns. In this paper, an artificial intelligence method is proposed for the synthesis of HIDF. It is based on the Database, Simulator, Heat Exchanger Network, and four Knowledge Bases which are all developed by the authors and their coworkers. A strategy of eight steps which combines the knowledge-based and rigorous algorithms is adopted for the synthesis of HIDF. The illustrated examples for the conventional distillation and extractive distillation show that the practical minimum energy consumption distillation flowsheets; can be generated with this method.

  9. 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.

  10. 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.

  11. Distillation under electric fields

    SciTech Connect

    Shah, V.M.; Blankenship, K.D.; Tsouris, C.

    1997-11-01

    Distillation Is the most common separation process used in the chemical and petroleum industry. Major limitations in the applicability and efficiency of distillation come from thermodynamic equilibria, that is, vapor-liquid equilibria (VLE), and heat and mass transfer rates. In this work, electric fields are used to manipulate the VLE of mixtures. VLE experiments are performed for various binary mixtures in the presence of electric fields on the order of a few kilovolts per centimeter. The results show that the VLE is changed by electric fields, with changes in the separation factor as high as 10% being observed. Batch distillation experiments are also carried out for binary mixtures of 2-propanol and water with and without an applied electric field. Results show enhanced distillation rates and separation efficiency in the presence of an electric field but decreased separation enhancement when the electric current is increased. The latter phenomenon is caused by the formation at the surface of the liquid mixture of microdroplets that are entrained by the vapor. These observations suggest that there should be an electric field strength for each system for which the separation enhancement is maximum.

  12. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

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

  13. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  14. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

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

  15. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  16. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

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

  17. 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

  18. A heat & mass integration approach to reduce capital and operating costs of a distillation configuration

    SciTech Connect

    Madenoor Ramapriya, Gautham; Jiang, Zheyu; Tawarmalani, Mohit; Agrawal, Rakesh

    2015-11-11

    We propose a general method to consolidate distillation columns of a distillation configuration using heat and mass integration. The proposed method encompasses all heat and mass integrations known till date, and includes many more. Each heat and mass integration eliminates a distillation column, a condenser, a reboiler and the heat duty associated with a reboiler. Thus, heat and mass integration can potentially offer significant capital and operating cost benefits. In this talk, we will study the various possible heat and mass integrations in detail, and demonstrate their benefits using case studies. This work will lay out a framework to synthesize an entire new class of useful configurations based on heat and mass integration of distillation columns.

  19. Distilling Abstract Machines Beniamino Accattoli

    E-print Network

    Mazza, Damiano

    Distilling Abstract Machines Beniamino Accattoli Carnegie Mellon University & Universit`a di rather distills them: some transitions are simulated while others vanish, as they map to a notion of structural congruence. The distillation process unveils that abstract machines in fact implement weak linear

  20. 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.

  1. 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...

  2. 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.

  3. Renormalising entanglement distillation

    E-print Network

    Stephan Waeldchen; Janina Gertis; Earl T. Campbell; Jens Eisert

    2015-03-16

    Entanglement distillation refers to the task of transforming a collection of weakly entangled pairs into fewer highly entangled ones. It is a core ingredient in quantum repeater protocols, needed to transmit entanglement over arbitrary distances in order to realise quantum key distribution schemes. Usually, it is assumed that the initial entangled pairs are i.i.d. distributed and uncorrelated with each other, an assumption that might not be reasonable at all in any entanglement generation process involving memory channels. Here, we introduce a framework that captures entanglement distillation in the presence of natural correlations arising from memory channels. Conceptually, we bring together ideas from condensed-matter physics - that of renormalisation and of matrix-product states and operators - with those of local entanglement manipulation, Markov chain mixing, and quantum error correction. We identify meaningful parameter regions for which we prove convergence to maximally entangled states, arising as the fixed points of a matrix-product operator renormalisation flow.

  4. 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.

  5. Stationary Apollonian Packings

    NASA Astrophysics Data System (ADS)

    Hirsch, Christian; Delaney, Gary; Schmidt, Volker

    2015-10-01

    The notion of stationary Apollonian packings in the d-dimensional Euclidean space is introduced as a mathematical formalization of so-called random Apollonian packings and rotational random Apollonian packings, which constitute popular grain packing models in physics. Apart from dealing with issues of existence and uniqueness in the entire Euclidean space, asymptotic results are provided for the growth durations and it is shown that the packing is space-filling with probability 1, in the sense that the Lebesgue measure of its complement is zero. Finally, the phenomenon is studied that grains arrange in clusters and properties related to percolation are investigated.

  6. 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…

  7. Harvesting and Packing Peaches. 

    E-print Network

    Lanham, W. B.

    1916-01-01

    Mechallical College of Texas (In co-operation with the United States Department of Agriculture.) MAY, 1916 EXTENSION SERVICE No. 8-22 Harvesting and Packing Peaches Fig. O.-A well packed basket of peaches. Address CLARENCE OUSLEY Director of Extension Service.... College Station. Texas HARVESTING AND PACKING PEACHES By W. B. Lanham, Horticulturist, Extension Service, Agricultural and Mechanical College of Texas The first thing to be considered in harvesting the peach crop is the equipment. As soon as danger...

  8. 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.

  9. 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,...

  10. 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,...

  11. 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,...

  12. 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,...

  13. 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,...

  14. 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

  15. 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

  16. 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…

  17. 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.

  18. Membrane distillation for high salinity desalination

    E-print Network

    Chung, Hyung Won

    2015-01-01

    Membrane distillation systems typically have low energy efficiency. Multistage membrane distillation (MD) systems can have significantly higher efficiencies than their single stage counterparts. However, multistage MD ...

  19. Radial heterogeneity of some analytical columns used in high-performance liquid chromatography

    SciTech Connect

    Mriziq, Khaled S; Guiochon, Georges A

    2009-01-01

    An on-column electrochemical microdetector was used to determine accurately the radial distribution of the mobile phase velocity and of the column efficiency at the exit of three common analytical columns, namely a 100 mm x 4.6 mm C18 bonded silica-based monolithic column, a 150 mm x 4.6 mm column packed with 2.7 {micro}m porous shell particles of C18 bonded silica (HALO), and a 150 mm x 4.6 mm column packed with 3 {micro}m fully porous C18 bonded silica particles (LUNA). The results obtained demonstrate that all three columns are not radially homogeneous. In all three cases, the efficiency was found to be lower in the wall region of the column than in its core region (the central core with a radius of 1/3 the column inner radius). The decrease in local efficiency from the core to the wall regions was lower in the case of the monolith (ca. 25%) than in that of the two particle-packed columns (ca. 35-50%). The mobile phase velocity was found to be ca. 1.5% higher in the wall than in the core region of the monolithic column while, in contrast, it was ca. 2.5-4.0% lower in the wall region for the two particle-packed columns.

  20. Graphitic packing removal tool

    DOEpatents

    Meyers, K.E.; Kolsun, G.J.

    1997-11-11

    Graphitic packing removal tools for removal of the seal rings in one piece are disclosed. The 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. 5 figs.

  1. 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.

  2. Graphitic packing removal tool

    SciTech Connect

    Meyers, K.E.; Kolsun, G.J.

    1996-12-31

    Graphitic packing removal tools are described for removal of the seal rings in one piece from valves and pumps. The 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.

  3. Influence of column design on process-scale ion-exchange chromatography.

    PubMed

    Levison, P R; Hopkins, A K; Hathi, P

    1999-12-31

    The performance of two new designs of pump-packed axial flow process chromatography columns have been evaluated for the preparative anion-exchange chromatography of hen egg-white proteins using Whatman Express-Ion Exchanger Q. A 16 1 Side-Pack column and a 24 1 IsoPak column containing Express-Ion Q were used in this study. In each case ca. 20 1 feedstock containing 5-7 g protein/l, was applied per litre packed bed at flow-rates of ca. 150 and 300 cm/h. In each case the ovalbumin binding capacity was ca. 70 g/l packed bed with ca. 100% (w/w) recovery of applied protein. A clean-in-place procedure involving storage in 0.5 M NaOH was effective in maintaining chromatographic performance in all cases. These data were consistent with our previous work using the more traditionally configured slurry-packed axial flow columns. Each of these column designs were easy to use facilitating rapid packing with this adsorbent and in the case of IsoPak rapid pump unpacking. The introduction of these column designs significantly improves the task of column packing, hitherto a labour intensive, physically demanding and potentially unreproducible process. PMID:10674926

  4. 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

  5. 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.

  6. Tiber winding pack design

    SciTech Connect

    Miller, J.R.

    1985-08-19

    A preliminary winding pack design was performed with the goal of showing feasibility of producing 10-T maximum field with a pack current density of 40 A.mm/sup -2/ while accepting 2.7 kW per coil nuclear heating. A cable-in-conduit conductor design (CIC), reported at the 6th Topical Meeting on the Technology of Fusion Energy, was based on several key issues.

  7. Quantum entanglement distillation with metamaterials.

    PubMed

    al Farooqui, Md Abdullah; Breeland, Justin; Aslam, Muhammad I; Sadatgol, Mehdi; Özdemir, ?ahin K; Tame, Mark; Yang, Lan; Güney, Durdu Ö

    2015-07-13

    We propose a scheme for the distillation of partially entangled two-photon Bell and three-photon W states using metamaterials. The distillation of partially entangled Bell states is achieved by using two metamaterials with polarization dependence, one of which is rotated by ?/2 around the direction of propagation of the photons. On the other hand, the distillation of three-photon W states is achieved by using one polarization dependent metamaterial and two polarization independent metamaterials. Upon transmission of the photons of the partially entangled states through the metamaterials the entanglement of the states increases and they become distilled. This work opens up new directions in quantum optical state engineering by showing how metamaterials can be used to carry out a quantum information processing task. PMID:26191854

  8. Revamp for more middle distillate

    SciTech Connect

    Weeks, D.J.; Pierce, V.E.

    1985-03-01

    In view of the continued decline in demand for residual fuel oil, the much publicised tightness of refining margins and hence funds for new investment, it is appropriate at this time to review some relatively inexpensive, but well-proven, revamp options that are available to the refiner for increasing yields of mid-distillate products at the expense of fuel oil components. With the partial or complete closure of so much refining capacity, much surplus equipment is available for implementing revamp projects. There is also scope for revamping hitherto moth-balled units and operating them in a manner different from that envisaged during their original design. Some long established conversion processes such as visbreaking and thermal cracking can enjoy a renaissance if demand for distillates remains strong. Mild hydrocracking and distillate dewaxing which are more recent developments in refinery processing can also figure prominently in plans for incremental production of middle distillates.

  9. 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...

  10. 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.

  11. Abstracts -1 Distill for CASP11

    E-print Network

    Pollastri, Gianluca

    Abstracts - 1 Distill Distill for CASP11 C. Mirabello, A.Adelfio and G. Pollastri UCD Dublin, Ireland gianluca.pollastri@ucd.ie Distill has two main components: a fold recognition stage dependent in the first stage. Methods Distill runs 3 rounds of PSI-BLAST against a 90% redundancy reduced Uni

  12. 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.

  13. Distillation process using microchannel technology

    SciTech Connect

    Tonkovich, Anna Lee; Simmons, Wayne W.; Silva, Laura J.; Qiu, Dongming; Perry, Steven T.; Yuschak, Thomas; Hickey, Thomas P.; Arora, Ravi; Smith, Amanda; Litt, Robert Dwayne; Neagle, Paul

    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.

  14. Momentive Performance Materials Distillation Intercharger 

    E-print Network

    Boucher, N.; Baisley, T.; Beers, C.; Cameron, R.; Holman, K.; Kotkoskie, T.; Norris, K.

    2013-01-01

    Program Momentive Performance Materials Distillation Interchanger ESL-IE-13-05-20 Proceedings of the Thrity-Fifth Industrial Energy Technology Conference New Orleans, LA. May 21-24, 2013 Copyright 2013 Momentive Performance Materials Inc. All rights... reserved. CONFIDENTIAL IETC Energy Efficiency Award Winner Distillation Interchanger ? Waterford, NY Agenda ? Momentive Overview ? Waterford, NY Site Overview ? Project Overview ? Project Timeline ? NYSERDA ? Project Team ? Best Practices...

  15. 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.

  16. Random Packing of Platonic Solids

    NASA Astrophysics Data System (ADS)

    Hersum, Taber; Lacasse, Martin-D.; King, Hubert

    2008-03-01

    While a large amount of literature has been devoted to the packing of spheres, very little is known about the packing of regular polyhedra, such as platonic solids. This presentation will describe numerical work on the packing of model systems in which mono-disperse tetrahedra, cubes, dodecahedra, and icosahedra are randomly packed.

  17. Mini-columns for Conducting Breakthrough Experiments. Design and Construction

    SciTech Connect

    Dittrich, Timothy M.; Reimus, Paul William; Ware, Stuart Douglas

    2015-06-11

    Experiments with moderately and strongly sorbing radionuclides (i.e., U, Cs, Am) have shown that sorption between experimental solutions and traditional column materials must be accounted for to accurately determine stationary phase or porous media sorption properties (i.e., sorption site density, sorption site reaction rate coefficients, and partition coefficients or Kd values). This report details the materials and construction of mini-columns for use in breakthrough columns to allow for accurate measurement and modeling of sorption parameters. Material selection, construction techniques, wet packing of columns, tubing connections, and lessons learned are addressed.

  18. 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...

  19. 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...

  20. Pessimal shapes for packing

    NASA Astrophysics Data System (ADS)

    Kallus, Yoav

    2014-03-01

    The question of which convex shapes leave the most empty space in their densest packing is the subject of Reinhardt's conjecture in two dimensions and Ulam's conjecture in three dimensions. Such conjectures about pessimal packing shapes have proven notoriously difficult to make progress on. I show that the regular heptagon is a local pessimum among all convex shapes, and that the 3D ball is a local pessimum among origin-symmetric shapes. Any shape sufficiently close in the space of shapes to these local pessima can be packed at a greater efficiency than they. In two dimensions and in dimensions above three, the ball is not a local pessimum, so the situation in 3D is unusual and intriguing. I will discuss what conditions conspire to make the 3D ball a local pessimum and whether we can prove that it is also a global pessimum.

  1. High-temperature separation with polymer-coated fiber in packed capillary gas chromatography.

    PubMed

    Saito, Yoshihiro; Ogawa, Mitsuhiro; Imaizumi, Motohiro; Ban, Kazuhiro; Abe, Akira; Takeichi, Tsutomu; Wada, Hiroo; Jinno, Kiyokatsu

    2005-06-01

    High-temperature gas chromatographic separation of several synthetic polymer mixtures with Dexsil-coated fiber-packed columns was studied. A bundle of heat-resistant filaments, Zylon, was longitudinally packed into a short metal capillary, followed by the conventional coating process with Dexsil 300 material. Prior to the packing process the metal capillary was deactivated by the formation of a silica layer. The typical size of the resulting column was 0.3-mm i.d., 0.5-mm o.d., 1-m length, and packed with about 170 filaments of the Dexsil-coated Zylon. The column temperature could be elevated up to 450 degrees C owing to the good thermal stability of the fiber, Dexsil coating, and metal capillary; furthermore, this allowed the separation of low-volatile compounds to be studied. PMID:15933854

  2. Optimal Protocols for Nonlocality Distillation

    E-print Network

    Hoyer, Peter

    2010-01-01

    Forster, Winkler, and Wolf 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 non-adaptive 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 new depth 3 protocol that extends the known region of distillable NLBs. We give examples of NLBs for which each of Forster et al.'s, Allcock et al.'s, and our protocol performs best. The new 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.

  3. Optimal Protocols for Nonlocality Distillation

    E-print Network

    Peter Hoyer; Jibran Rashid

    2010-09-09

    Forster, Winkler, and Wolf 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 non-adaptive 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 new depth 3 protocol that extends the known region of distillable NLBs. We give examples of NLBs for which each of Forster et al.'s, Allcock et al.'s, and our protocol performs best. The new 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.

  4. Optimal protocols for nonlocality distillation

    SciTech Connect

    Hoeyer, Peter; Rashid, Jibran

    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.

  5. Evaluating two process scale chromatography column header designs using CFD.

    PubMed

    Johnson, Chris; Natarajan, Venkatesh; Antoniou, Chris

    2014-01-01

    Chromatography is an indispensable unit operation in the downstream processing of biomolecules. Scaling of chromatographic operations typically involves a significant increase in the column diameter. At this scale, the flow distribution within a packed bed could be severely affected by the distributor design in process scale columns. Different vendors offer process scale columns with varying design features. The effect of these design features on the flow distribution in packed beds and the resultant effect on column efficiency and cleanability needs to be properly understood in order to prevent unpleasant surprises on scale-up. Computational Fluid Dynamics (CFD) provides a cost-effective means to explore the effect of various distributor designs on process scale performance. In this work, we present a CFD tool that was developed and validated against experimental dye traces and tracer injections. Subsequently, the tool was employed to compare and contrast two commercially available header designs. PMID:24616438

  6. Solar power water distillation unit

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

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

  7. Improving the Performance of a Two-Shell Column with Advanced Control 

    E-print Network

    Morrison, T. A.; Laflamme, D.

    1991-01-01

    THE PERFORMANCE OF A TWO-SHELL COLUMN WITH ADVANCED CONTROL TIMOTHY A. MORRISON SENIOR PROJECT ENGINEER SETPOINT Inc. Houston, Texas ABSTRACT Application of advanced control techniques to a two-shell, two- pressure distillation column has yielded stable..., shell load balancing and pressure minimization. The key to successful control of this column is the load balancing strategy which maintains continuous vapor and liquid profiles throughout the tower. SUMMARY As part of a larger computer control...

  8. Solar distillation of sea water

    SciTech Connect

    Subramanyam, S. )

    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.

  9. 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.

  10. Bounds for nonlocality distillation protocols

    SciTech Connect

    Forster, Manuel

    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.

  11. 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,…

  12. TCAP HYDROGEN ISOTOPE SEPARATION USING PALLADIUM AND INVERSE COLUMNS

    SciTech Connect

    Heung, L.; Sessions, H.; Xiao, S.

    2010-08-31

    The Thermal Cycling Absorption Process (TCAP) was further studied with a new configuration. Previous configuration used a palladium packed column and a plug flow reverser (PFR). This new configuration uses an inverse column to replace the PFR. The goal was to further improve performance. Both configurations were experimentally tested. The results showed that the new configuration increased the throughput by a factor of more than 2.

  13. Effect of packing method on the randomness of disc packings

    NASA Astrophysics Data System (ADS)

    Zhang, Z. P.; Yu, A. B.; Oakeshott, R. B. S.

    1996-06-01

    The randomness of disc packings, generated by random sequential adsorption (RSA), random packing under gravity (RPG) and Mason packing (MP) which gives a packing density close to that of the RSA packing, has been analysed, based on the Delaunay tessellation, and is evaluated at two levels, i.e. the randomness at individual subunit level which relates to the construction of a triangle from a given edge length distribution and the randomness at network level which relates to the connection between triangles from a given triangle frequency distribution. The Delaunay tessellation itself is also analysed and its almost perfect randomness at the two levels is demonstrated, which verifies the proposed approach and provides a random reference system for the present analysis. It is found that (i) the construction of a triangle subunit is not random for the RSA, MP and RPG packings, with the degree of randomness decreasing from the RSA to MP and then to RPG packing; (ii) the connection of triangular subunits in the network is almost perfectly random for the RSA packing, acceptable for the MP packing and not good for the RPG packing. Packing method is an important factor governing the randomness of disc packings.

  14. Optimization of blended battery packs

    E-print Network

    Erb, Dylan C. (Dylan Charles)

    2013-01-01

    This thesis reviews the traditional battery pack design process for hybrid and electric vehicles, and presents a dynamic programming (DP) based algorithm that eases the process of cell selection and pack design, especially ...

  15. 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.

  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. 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.

  18. 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.

  19. Entanglement preservation by continuous distillation

    SciTech Connect

    Mundarain, D.; Orszag, M.

    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.

  20. Green chemical engineering aspects of reactive distillation.

    PubMed

    Malone, Michael F; Huss, Robert S; Doherty, Michael F

    2003-12-01

    Reactive or catalytic distillation technology combines chemical synthesis steps with separations by distillation. This combination can lead to intensified, high-efficiency process systems with significant green engineering attributes. New applications and understanding have prompted growth in the use of reactive distillation for a variety of chemical syntheses, especially esterifications and etherifications involving oxygenated hydrocarbons. We describe several applications and the potential and tradeoffs for reactive distillation technology in the context of green engineering principles. PMID:14700316

  1. 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.

  2. 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.

  3. 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....

  4. 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 multieffect batch distillation, operation and control, distillation lines INTRODUCTION By closed multivessel batch distillation we mean a "total reflux" operation where the products are accumulated in vessels

  5. Zenix SEC Column Manual Column Information

    E-print Network

    Lebendiker, Mario

    1 Zenix SEC Column Manual Column Information Utilizing proprietary surface technologies and 3 m particle size, Zenix SEC phases are made of uniform, hydrophilic, and neutral nanometer thick films SEC phases with high stability. The uniform surface coating enables high efficiency separation

  6. 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.

  7. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distilled spirits. 27.40 Section 27.40 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  8. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distilled spirits. 27.40 Section 27.40 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  9. 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...

  10. 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

  11. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  12. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  13. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  14. 27 CFR 19.316 - Distillation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distillation. 19.316 Section 19.316 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Production § 19.316 Distillation. The...

  15. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  16. 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

  17. Mechanisms of recirculating liquid flow on distillation sieve plates

    SciTech Connect

    Biddulph, M.W. . Dept. of Chemical Engineering); Burton, A.C. )

    1994-11-01

    This paper describes an experimental investigation into the phenomenon of flow recirculation on distillation sieve trays. A novel dye injection technique has been applied to a 1.81 m air-water simulation column and has yielded new information concerning the nature of the boundary layer of gas-liquid biphase as it detaches from the column wall. The study has shown that recirculation is strongly influenced by inlet conditions. A critical factor is the underflow clearance between the inlet downcomer apron and the tray floor. As this clearance is increased, the size of the recirculating zones passes through a minimum, indicating the existence of two different mechanisms responsible for the nonuniform flow patterns. A significant implication of this work is that tray designers may minimize the impact of recirculating on mass transfer efficiency by appropriate choice of underflow clearance.

  18. 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...

  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. 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...

  1. 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...

  2. 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...

  3. Better sieve tray. Add packing

    SciTech Connect

    Salem, A.B.S.H.; Alsaygh, A.A.

    1988-05-01

    Some conclusions from the authors' investigation are as follows: Packing on sieve trays significantly improves mass transfer by increasing interfacial area. Packing increases the average degree of separation of sieve tray tower more than 20%. Stacked stainless steel packing of 11.5 cm height gave the highest purity. Optimum height may be about 10 cm for our tower. A pressure drop increase of about 30% results in the case of using packing. Using packing gives an increase of 21% in the overall tower efficiency and 22.5% in the Murphree efficiency of the vapor phase.

  4. Enumerating rigid sphere packings

    E-print Network

    Miranda C. Holmes-Cerfon

    2015-05-08

    Packing problems, which ask how to arrange a collection of objects in space to meet certain criteria, are important in a great many physical and biological systems, where geometrical arrangements at small scales control behaviour at larger ones. In many systems there is no single, optimal packing that dominates, but rather one must understand the entire set of possible packings. As a step in this direction we enumerate rigid clusters of identical hard spheres for $n\\leq 14$, and clusters with the maximum number of contacts for $n\\leq 19$. A rigid cluster is one that cannot be continuously deformed while maintaining all contacts. This is a nonlinear notion that arises naturally because such clusters are the metastable states when the spheres interact with a short-range potential, as is the case in many nano- or micro-scale systems. We expect these lists are nearly complete, except for a small number of highly singular clusters (linearly floppy but nonlinearly rigid.) The data contains some major geometrical surprises, such as the prevalence of hypostatic clusters: those with less than the $3n-6$ contacts generically necessary for rigidity. We discuss these and several other unusual clusters, whose geometries may shed insight into physical mechanisms, pose mathematical and computational problems, or bring inspiration for designing new materials.

  5. 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 ...

  6. Superdense Crystal Packings of Ellipsoids

    E-print Network

    Aleksandar Donev; Frank H. Stillinger; P. M. Chaikin; Salvatore Torquato

    2004-03-10

    Particle packing problems have fascinated people since the dawn of civilization, and continue to intrigue mathematicians and scientists. Resurgent interest has been spurred by the recent proof of Kepler's conjecture: the face-centered cubic lattice provides the densest packing of equal spheres with a packing fraction $\\phi\\approx0.7405$ \\cite{Kepler_Hales}. Here we report on the densest known packings of congruent ellipsoids. The family of new packings are crystal (periodic) arrangements of nearly spherically-shaped ellipsoids, and always surpass the densest lattice packing. A remarkable maximum density of $\\phi\\approx0.7707$ is achieved for both prolate and oblate ellipsoids with aspect ratios of $\\sqrt{3}$ and $1/\\sqrt{3}$, respectively, and each ellipsoid has 14 touching neighbors. Present results do not exclude the possibility that even denser crystal packings of ellipsoids could be found, and that a corresponding Kepler-like conjecture could be formulated for ellipsoids.

  7. 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.

  8. 3D printed metal columns for capillary liquid chromatography.

    PubMed

    Sandron, S; Heery, B; Gupta, V; Collins, D A; Nesterenko, E P; Nesterenko, P N; Talebi, M; Beirne, S; Thompson, F; Wallace, G G; Brabazon, D; Regan, F; Paull, B

    2014-12-21

    Coiled planar capillary chromatography columns (0.9 mm I.D. × 60 cm L) were 3D printed in stainless steel (316L), and titanium (Ti-6Al-4V) alloys (external dimensions of ~5 × 30 × 58 mm), and either slurry packed with various sized reversed-phase octadecylsilica particles, or filled with an in situ prepared methacrylate based monolith. Coiled printed columns were coupled directly with 30 × 30 mm Peltier thermoelectric direct contact heater/cooler modules. Preliminary results show the potential of using such 3D printed columns in future portable chromatographic devices. PMID:25285334

  9. Column Liquid Chromatography.

    ERIC Educational Resources Information Center

    Majors, Ronald E.; And Others

    1984-01-01

    Reviews literature covering developments of column liquid chromatography during 1982-83. Areas considered include: books and reviews; general theory; columns; instrumentation; detectors; automation and data handling; multidimensional chromatographic and column switching techniques; liquid-solid chromatography; normal bonded-phase, reversed-phase,…

  10. 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.

  11. Assisted distillation of quantum coherence

    E-print Network

    E. Chitambar; A. Streltsov; S. Rana; M. N. Bera; G. Adesso; M. Lewenstein

    2015-07-29

    We introduce and study the task of assisted coherence distillation. This task arises naturally in bipartite systems where both parties work together to generate the maximal possible coherence on one of the subsystems. Only incoherent operations are allowed on the target system while general local quantum operations are permitted on the other, an operational paradigm that we call local quantum-incoherent operations and classical communication (LQICC). We show that the asymptotic rate of assisted coherence distillation for pure states is equal to the coherence of assistance, a direct analog of the entanglement of assistance, whose properties we characterize. Our findings imply a novel interpretation of the von Neumann entropy: it quantifies the maximum amount of extra quantum coherence a system can gain when receiving assistance from a collaborative party. Our results are generalized to coherence localization in a multipartite setting and possible applications are discussed.

  12. Assisted distillation of quantum coherence

    E-print Network

    Chitambar, E; Rana, S; Bera, M N; Adesso, G; Lewenstein, M

    2015-01-01

    We introduce and study the task of assisted coherence distillation. This task arises naturally in bipartite systems where both parties work together to generate the maximal possible coherence on one of the subsystems. Only incoherent operations are allowed on the target system while general local quantum operations are permitted on the other, an operational paradigm that we call local quantum-incoherent operations and classical communication (LQICC). We show that the asymptotic rate of assisted coherence distillation for pure states is equal to the coherence of assistance, a direct analog of the entanglement of assistance, whose properties we characterize. Our findings imply a novel interpretation of the von Neumann entropy: it quantifies the maximum amount of extra quantum coherence a system can gain when receiving assistance from a collaborative party. Our results are generalized to coherence localization in a multipartite setting and possible applications are discussed.

  13. 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...

  14. EFFECT OF NITRATE-BASED BIOREMEDIATION ON CONTAMINANT DISTRIBUTION AND SEDIMENT TOXICITY-COLUMN STUDY

    EPA Science Inventory

    A laboratory column study was set up to evaluate changes in contaminant distribution and sediment toxicity following nitrate-based bioremediation and to correlate toxicity reduction with loss of fuel components. Glass columns were packed with sediment from an aquifer that had be...

  15. Endurance Test for SCK-CEN Catalytic Mixed Packing, Proposed for Water Detritiation System at JET

    SciTech Connect

    Ionita, Gh.; Bornea, A.; Braet, J.; Popescu, I.; Stefanescu, I.; Bidica, N.; Varlam, C; Postolache, Cr.; Mateic, L.

    2005-07-15

    JET machine's operation lead to continuously generation of tritiated water and therefore, it is necessary to consider the development of a Water Detritiation System (WDS) for JET and also for ITER. The key point of WDS is the efficiency and stability of liquid phase catalytic exchange (LPCE) column, that has to achieve a high decontamination of tritiated streams.Two catalytic mixed packing based on hydrophobic Pt-catalyst, and having closed separation performances have been proposed for LPCE column. A complete data base concerning the influence of {beta}-radiation of tritium and the influence of impurities from feed streams on the catalytic mixed packing' s performances and parameters is absolutely necessary.The results of 3 months endurance test for one of these packing (SCK-CEN packing), are presented in this paper. No significant modifications of performances and physico-structural parameters have been observed.

  16. Small Codes for Magic State Distillation

    E-print Network

    Mark Howard; Hillary Dawkins

    2015-12-15

    Magic state distillation is a critical component in leading proposals for fault-tolerant quantum computation. Relatively little is known, however, about how to construct a magic state distillation routine or, more specifically, which stabilizer codes are suitable for the task. While transversality of a non-Clifford gate within a code often leads to efficient distillation routines, it appears to not be a necessary condition. Here we have examined a number of small stabilizer codes and highlight a handful of which displaying interesting, albeit inefficient, distillation behaviour. Many of these distill noisy states right up to the boundary of the known undististillable region, while some distill toward non-stabilizer states that have not previously been considered.

  17. Inelastic column behavior

    NASA Technical Reports Server (NTRS)

    Duberg, John E; Wilder, Thomas W , III

    1952-01-01

    The significant findings of a theoretical study of column behavior in the plastic stress range are presented. When the behavior of a straight column is regarded as the limiting behavior of an imperfect column as the initial imperfection (lack of straightness) approaches zero, the departure from the straight configuration occurs at the tangent-modulus load. Without such a concept of the behavior of a straight column, one is led to the unrealistic conclusion that lateral deflection of the column can begin at any load between the tangent-modulus value and the Euler load, based on the original elastic modulus. A family of curves showing load against lateral deflection is presented for idealized h-section columns of various lengths and of various materials that have a systematic variation of their stress-strain curves.

  18. 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.

  19. Spiral multicapillary columns

    NASA Astrophysics Data System (ADS)

    Efimenko, A. P.; Naumenko, I. I.; Soboleva, V. K.

    2008-08-01

    It was shown in a theoretical study and confirmed by experiment that a spiral multicapillary column had maximum efficiency if the bunch of capillaries was additionally coiled around its longitudinal axis to produce an integral number of coils. This technique made it possible to manufacture gas-chromatographic columns with performance as high as 12 to 16 thousand theoretical plates. These columns can find various applications, especially if quick separation is required.

  20. 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.

  1. 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.

  2. Quantum macroscopicity versus distillation of macroscopic superpositions

    NASA Astrophysics Data System (ADS)

    Yadin, Benjamin; Vedral, Vlatko

    2015-08-01

    We suggest a way to quantify a type of macroscopic entanglement via distillation of Greenberger-Horne-Zeilinger states by local operations and classical communication. We analyze how this relates to an existing measure of quantum macroscopicity based on the quantum Fisher information in several examples. Both cluster states and Kitaev surface code states are found to not be macroscopically quantum but can be distilled into macroscopic superpositions. We look at these distillation protocols in more detail and ask whether they are robust to perturbations. One key result is that one-dimensional cluster states are not distilled robustly but higher-dimensional cluster states are.

  3. Quantum macroscopicity versus distillation of macroscopic superpositions

    E-print Network

    Benjamin Yadin; Vlatko Vedral

    2015-09-15

    We suggest a way to quantify a type of macroscopic entanglement via distillation of Greenberger-Horne-Zeilinger states by local operations and classical communication. We analyze how this relates to an existing measure of quantum macroscopicity based on the quantum Fisher information in several examples. Both cluster states and Kitaev surface code states are found to not be macroscopically quantum but can be distilled into macroscopic superpositions. We look at these distillation protocols in more detail and ask whether they are robust to perturbations. One key result is that one-dimensional cluster states are not distilled robustly but higher-dimensional cluster states are.

  4. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  5. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  6. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  7. 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…

  8. 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

  9. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... residues and ethylamine distillation residues. (a) Chemical substances and significant new use subject...

  10. The kinetics of carboxymethylcellulose-ficin in packed beds

    PubMed Central

    Lilly, M. D.; Hornby, W. E.; Crook, E. M.

    1966-01-01

    1. The kinetics of the hydrolysis of benzoylarginine ethyl ester in packed columns of CM-cellulose-70–ficin and CM-cellulose-90–ficin were studied. 2. The apparent Michaelis constant, K?m, of these preparations was calculated and shown to be dependent on the flow rate at low rates of perfusion through the columns. 3. The values for k3 of these preparations were calculated and shown to be nearly independent of flow rate. 4. A modified form of the integrated Michaelis rate equation was used to describe the action of these materials and its limitations are discussed. 5. The hydrolysis of solutions of casein by these columns was studied. PMID:5969284

  11. Method for gravel packing wells

    SciTech Connect

    Yeh, C.S.

    1991-12-31

    This patent describes a method for gravel packing a perforated well which penetrates a formation or reservoir. It comprises placing into a solution a shear-thickening composition in an amount sufficient to form a carrier fluid having a viscosity sufficient to suspend gravel packing sand therein for a time sufficient to pack the well; adding gravel packing sand into the fluid thereby suspending the sand therein; injecting the carrier fluid and sand mixture into the well under conditions sufficient to cause the mixture to shear thicken so as to provide for transportation of the sand to perforations in the well without spreading from the mixture; and directing the mixture into the perforations which diminishes shear forces acting on the mixture thereby causing a reduction in viscosity of the carrier fluid, sand separation from the fluid, improved fluid leak-off into the formation, and uniform gravel packing of the perforations.

  12. 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....

  13. Inflatable Column Structure

    NASA Technical Reports Server (NTRS)

    Hedgepeth, J. M.

    1985-01-01

    Lightweight structural member easy to store. Billowing between circumferential loops of fiber inflated column becomes series of cells. Each fiber subjected to same tension along entire length (though tension is different in different fibers). Member is called "isotensoid" column. Serves as jack for automobiles or structures during repairs. Also used as support for temporary bleachers or swimming pools.

  14. 7 CFR 51.1005 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Persian (Tahiti) Limes Standard Pack § 51.1005 Standard pack. (a) Fruit shall be fairly uniform in size, and when place packed in...

  15. 7 CFR 51.1005 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Persian (Tahiti) Limes Standard Pack § 51.1005 Standard pack. (a) Fruit shall be fairly uniform in size, and when place packed in...

  16. 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....

  17. 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....

  18. 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....

  19. 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....

  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 51.1270 - Packing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing. (a) Each package shall be packed so that the pears in the shown...

  2. 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 ...

  3. Medial column stabilization.

    PubMed

    Catanzariti, A R

    1991-07-01

    This article presented a brief review of medial column stabilizing procedures. The various types of procedures that have been advocated for different deformities have been discussed. It is important to keep in mind that fusion of any of the medial column joints should not be performed as an isolated procedure in flexible flatfoot deformity. Medial column stabilization is only a component procedure when surgically managing a flexible flatfoot. When choosing procedures to correct a flexible flatfoot, thorough preoperative evaluation is important. It is also important to realize that conservative measures should be exhausted before attempting any type of stabilization of the medial column for flexible flatfoot deformity. Specific criteria for flexible flatfoot surgery should include severe uncontrollable deformity, an inability to wear standard foot gear, and persistent pain and disability despite exhaustive conservative therapy. A medial column stabilization is also an excellent procedure for those patients who have end-stage degenerative joint disease of the medial longitudinal arch. PMID:1893342

  4. 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.

  5. Model of decision system for 13C Isotope Separation column

    NASA Astrophysics Data System (ADS)

    Boca, M. L.

    2015-11-01

    This paper presents the model of a decisional system for 13C Isotope Separation column, which is used to detect mission critical situation. The start model was a model of one distributed control system of critical situations that may arise in the operation of the distillation column. The research work it is proposed a model of decision system which implement a temperature sensor inside of liquid nitrogen level in the condenser. The condenser is a part of column where take place the cryogenic process using nitrogen liquid. The work temperature is very low about -192oC, and because the temperature can grow or go down more than 2 degrees is a very critical location inside the column. In this way the column has a deeply monitor and supervised and it take a decision in a proper time when the temperature is grow up or getting down and became a critical situation. For monitor and supervised it was used MatLAB SimuLink. The model, the decision system gives a signal to one sensor when something is wrong in the condenser which is the most critical place of the isotopic column. In this way it creates an alarm that something is getting wrong in the isotopic column.

  6. 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...

  7. 7 CFR 58.331 - Starter distillate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Starter distillate. 58.331 Section 58.331 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.331 Starter distillate. The refined flavor components when used to flavor butter and...

  8. 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…

  9. Distillation of Bell states in open systems

    SciTech Connect

    Isasi, E.; Mundarain, D.

    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.

  10. 27 CFR 27.31 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Warehouse receipts covering distilled spirits...Registration and Recordkeeping § 27.31 Warehouse receipts covering distilled spirits. The sale of warehouse receipts for distilled spirits...

  11. 27 CFR 26.45 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Warehouse receipts covering distilled spirits...Registration and Recordkeeping § 26.45 Warehouse receipts covering distilled spirits. The sale of warehouse receipts for distilled spirits...

  12. 27 CFR 26.211 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Warehouse receipts covering distilled spirits...Registration and Recordkeeping § 26.211 Warehouse receipts covering distilled spirits. The sale of warehouse receipts for distilled spirits...

  13. 27 CFR 26.45 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Warehouse receipts covering distilled spirits...Registration and Recordkeeping § 26.45 Warehouse receipts covering distilled spirits. The sale of warehouse receipts for distilled spirits...

  14. 27 CFR 27.31 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Warehouse receipts covering distilled spirits...Registration and Recordkeeping § 27.31 Warehouse receipts covering distilled spirits. The sale of warehouse receipts for distilled spirits...

  15. 27 CFR 26.211 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Warehouse receipts covering distilled spirits...Registration and Recordkeeping § 26.211 Warehouse receipts covering distilled spirits. The sale of warehouse receipts for distilled spirits...

  16. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Destructively distilled wood turpentine. 160.9 Section 160.9...General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind...

  17. 27 CFR 19.651 - Liability for distilled spirits tax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...TREASURY LIQUORS DISTILLED SPIRITS PLANTS Production of Vinegar by the Vaporizing Process Liability for Distilled Spirits...distilled spirits produced in, or removed from, the premises of a vinegar plant in violation of law or regulations. (26...

  18. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  19. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  20. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  1. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  2. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  3. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  4. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 2014-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  5. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 2013-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  6. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 2011-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  7. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 2012-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  8. 27 CFR 19.32 - Experimental distilled spirits plants.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...false Experimental distilled spirits plants. 19.32 Section 19.32 Alcohol...TREASURY LIQUORS DISTILLED SPIRITS PLANTS Administrative and Miscellaneous Provisions...32 Experimental distilled spirits plants. (a) General. The...

  9. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. (a) Chemical...chemical substance identified generically as terpene residue distillates (PMN...

  10. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. Link to an amendment...chemical substance identified generically as terpene residue distillates (PMN...

  11. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. (a) Chemical...chemical substance identified generically as terpene residue distillates (PMN...

  12. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. (a) Chemical...chemical substance identified generically as terpene residue distillates (PMN...

  13. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. (a) Chemical...chemical substance identified generically as terpene residue distillates (PMN...

  14. 27 CFR 19.65 - Experimental distilled spirits plants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...false Experimental distilled spirits plants. 19.65 Section 19.65 Alcohol...TREASURY LIQUORS DISTILLED SPIRITS PLANTS Administrative and Miscellaneous Provisions...65 Experimental distilled spirits plants. The appropriate TTB officer may...

  15. Reduced distillation models via stage aggregation Andreas Linhart

    E-print Network

    Skogestad, Sigurd

    Reduced distillation models via stage aggregation Andreas Linhart , Sigurd Skogestad Department, 2009 Abstract A method for deriving computationally efficient reduced nonlinear distillation models improvements are discussed. Keywords Model reduction; Distillation; Aggregated modeling; Real-time optimizing

  16. 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.

  17. 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.

  18. Hard sphere packings within cylinders

    E-print Network

    Lin Fu; William Steinhardt; Hao Zhao; Joshua E. S. Socolar; Patrick Charbonneau

    2015-11-26

    The packing of hard spheres (HS) of diameter $\\sigma$ in a cylinder has been used to model experimental systems, such as fullerenes in nanotubes and colloidal wire assembly. Finding the densest packings of HS under this type of confinement, however, grows increasingly complex with the cylinder diameter, $D$. Little is thus known about the densest achievable packings for $D>2.873\\sigma$. In this work, we extend the identification of the packings up to $D=4.00\\sigma$ by adapting Torquato-Jiao's adaptive-shrinking-cell formulation and sequential-linear-programming (SLP) technique. We identify 17 new structures, almost all of them chiral. Beyond $D\\approx2.85\\sigma$, most of the structures consist of an outer shell and an inner core that compete for being close packed. In some cases, the shell adopts its own maximum density configuration, and the stacking of core spheres within it is quasiperiodic. In other cases, an interplay between the two components is observed, which may result in simple periodic structures. In yet other cases, the very distinction between core and shell vanishes, resulting in more exotic packing geometries, including some that are three-dimensional extensions of structures obtained from packing hard disks in a circle.

  19. Recycling of acetone by distillation

    SciTech Connect

    Brennan, D.L.; Campbell, B.A.; Phelan, J.E.; Harper, M.

    1992-09-01

    The Resource Conservation Recovery Act (RCRA) identifies spent acetone solvent as a listed hazardous waste. At Fernald, acetone has been spent that has been contaminated with radionuclides and therefore is identified as a mixed hazardous waste. At the time of this publication there is no available approved method of recycling or disposal of radioactively contaminated spent acetone solvent. The Consent Decree with the Ohio EPA and the Consent Agreement with the United States EPA was agreed upon for the long-term compliant storage of hazardous waste materials. The purpose of this project was to demonstrate the feasibility for safely decontaminating spent acetone to background levels of radioactivity for reuse. It was postulated that through heat distillation, radionuclides could be isolated from the spent acetone.

  20. Nuclear reactor control column

    DOEpatents

    Bachovchin, Dennis M. (Plum Borough, PA)

    1982-01-01

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  1. Low capital implementation of distributed distillation in ethylene recovery

    DOEpatents

    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.

  2. Design and operating targets for nonideal multicomponent batch distillation

    SciTech Connect

    Bernot, C.; Doherty, M.F.; Malone, M.F. )

    1993-02-01

    A method is reported to estimate the batch sizes, operating times, equipment sizes, utility loads, and costs for the batch distillation of nonideal multicomponent mixtures. The method provides an estimate for both the design and the operating policy for the reflux or reboil ratio without the need to integrate the full column model numerically. This operating policy approximates the constant product composition policy for high purities and high fractional recoveries and shows a substantial cost savings over the constant reflux or reboil policies, primarily on account of a substantial reduction in the vapor rate. The approach provides a good approximation to the results of a detailed optimization in an example for a binary mixture. A more interesting application is illustrated for the separation of a quaternary azeotropic mixture arising from the transesterification of ethyl acetate with methanol to produce ethanol and methyl acetate.

  3. Novel fractionation method for squalene and phytosterols contained in the deodorization distillate of rice bran oil.

    PubMed

    Sugihara, Naoko; Kanda, Ayato; Nakano, Teruyuki; Nakamura, Takahiro; Igusa, Hisao; Hara, Setsuko

    2010-01-01

    Since deodorization distillate, a by-product of rice bran oil production, contains squalene (ca. 8%) and phytosterols (ca. 4%) as unsaponifiable components, the concentration of those materials for their use in the cosmetics and food industries is desirable. In the present work, a novel fractionation method of concentrating squalene and phytosterols from deodorization distillate or the unsaponifiable components of the deodorization distillate without oxidative deterioration was examined. Supercritical fluid extraction (SFE) with supercritical carbon dioxide was investigated under the following conditions: temperature, 30 degrees C; pressure, 100 kg/cm(2); flow rate of carbon dioxide, 7 mL/min. Under these conditions, squalene was effectively concentrated to 25% with nearly quantitative recovery, and then a more highly concentrated squalene (ca. 50% purity) was obtained by using a supercritical fluid chromatography (SFC) with silica gel packed into the extraction vessel. In addition, squalene with ca. 68% purity could be obtained by repeating the SFC twice. After the saponification of the deodorization distillate, followed by solvent fractionation with hexane, highly purified phytosterols (97% purity) could be obtained, and highly purified squalene (81% and 100% purity) could be also obtained by using SFC combined with the solvent fractionation technique for the unsaponifiable materials. Therefore, it is considered that the present fractionation method combined with SFC and solvent fractionation is an effective means of concentrating squalene and phytosterols. PMID:20103978

  4. 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

  5. Packed Bed Combustion: An Overview

    E-print Network

    Hallett, William L.H.

    , this was the main means of burning coal, wood, coke and charcoal - up to 7 tons/hr (. 50MW heat release (radiative/kinetic) - for 3.2cm coke particles (carbon combustion only) #12;Packed Bed Combustion

  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. 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

  8. 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.

  9. Entanglement Distillation using the Exchange Interaction

    E-print Network

    Adrian Auer; René Schwonnek; Christian Schoder; Lars Dammeier; Reinhard F. Werner; Guido Burkard

    2015-08-03

    A key ingredient of quantum repeaters is entanglement distillation, i.e., the generation of high-fidelity entangled qubits from a larger set of pairs with lower fidelity. Here, we present entanglement distillation protocols based on qubit couplings that originate from exchange interaction. First, we make use of asymmetric bilateral two-qubit operations generated from anisotropic exchange interaction and show how to distill entanglement using two input pairs. We furthermore consider the case of three input pairs coupled through isotropic exchange. Here, we characterize a set of protocols which are optimizing the tradeoff between the fidelity increase and the probability of a successful run.

  10. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  11. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S....

  12. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S....

  13. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  14. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  15. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  16. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. Liquid chromatographic determination of scopoletin in hydroalcoholic extract of oak wood and in matured distilled alcoholic beverages.

    PubMed

    Puech, J L; Moutounet, M

    1988-01-01

    A liquid chromatographic (LC) method is described for determination of the coumarins esculin, umbelliferone, scopoletin, and 4-methyl umbelliferone in hydroalcoholic extracts of oak wood and in matured distilled alcoholic beverages. Samples were injected directly into the LC column (30 cm, 5 micron C18) and detected by fluorescence detector. Under these experimental conditions, only scopoletin (detection limit, 200 pg) was found in hydroalcoholic oak wood extracts and in spirits matured in oak wood. Applications of this method to spirits distilled from wine, grain, and sugar cane aged in oak barrels showed that amounts varied from 0.026 to 1.57 ppm. PMID:3391951

  7. HEAT TRANSFER ANALYSIS FOR ION-EXCHANGE COLUMN SYSTEM

    SciTech Connect

    Lee, S.; King, W.

    2011-05-23

    Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed, inadvertent column drainage, and loss of active cooling in the column. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature.

  8. 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.

  9. High pressure humidification columns: Design equations, algorithm, and computer code

    SciTech Connect

    Enick, R.M.; Klara, S.M.; Marano, J.J.

    1994-07-01

    This report describes the detailed development of a computer model to simulate the humidification of an air stream in contact with a water stream in a countercurrent, packed tower, humidification column. The computer model has been developed as a user model for the Advanced System for Process Engineering (ASPEN) simulator. This was done to utilize the powerful ASPEN flash algorithms as well as to provide ease of use when using ASPEN to model systems containing humidification columns. The model can easily be modified for stand-alone use by incorporating any standard algorithm for performing flash calculations. The model was primarily developed to analyze Humid Air Turbine (HAT) power cycles; however, it can be used for any application that involves a humidifier or saturator. The solution is based on a multiple stage model of a packed column which incorporates mass and energy, balances, mass transfer and heat transfer rate expressions, the Lewis relation and a thermodynamic equilibrium model for the air-water system. The inlet air properties, inlet water properties and a measure of the mass transfer and heat transfer which occur in the column are the only required input parameters to the model. Several example problems are provided to illustrate the algorithm`s ability to generate the temperature of the water, flow rate of the water, temperature of the air, flow rate of the air and humidity of the air as a function of height in the column. The algorithm can be used to model any high-pressure air humidification column operating at pressures up to 50 atm. This discussion includes descriptions of various humidification processes, detailed derivations of the relevant expressions, and methods of incorporating these equations into a computer model for a humidification column.

  10. Absorptive Recycle of Distillation Waste Heat 

    E-print Network

    Erickson, D. C.; Lutz, E. J., Jr.

    1982-01-01

    condenser operates above ambient temperature, the rejected heat also contains unused availability. By incorporating an absorption heat pump (AHP) into the distillation process, these sources of unused availability can be tapped so as to recycle (and hence...

  11. Advanced Distillation: Programs Proposed to DOE 

    E-print Network

    Woinsky, S. G.

    2001-01-01

    EPRI has provided proposal preparation assistance and offered cost share funding assistance for two projects proposed in 2000. EPRI is highly interested, since this technology is applicable in all distillation systems, and since it will increase...

  12. Energy Recovery in Industrial Distillation Processes 

    E-print Network

    Paul, D. B.

    1983-01-01

    Distillation processes are energy intensive separation processes which present attractive opportunities for energy conservation. Through the use of multistage vapor recompression, heat which is normally unavailable can be delivered at suitably high...

  13. Minimizing corrosion in coal liquid distillation

    DOEpatents

    Baumert, Kenneth L. (Emmaus, PA); Sagues, Alberto A. (Lexington, KY); Davis, Burtron H. (Georgetown, KY)

    1985-01-01

    In an atmospheric distillation tower of a coal liquefaction process, tower materials corrosion is reduced or eliminated by introduction of boiling point differentiated streams to boiling point differentiated tower regions.

  14. 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 ...

  15. 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 ...

  16. 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...

  17. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  18. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  19. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  20. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  1. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  2. 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

  3. 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

  4. Polymer-coated fibrous materials as the stationary phase in packed capillary gas chromatography.

    PubMed

    Saito, Yoshihiro; Tahara, Ai; Imaizumi, Motohiro; Takeichi, Tsutomu; Wada, Hiroo; Jinno, Kiyokatsu

    2003-10-15

    Synthetic polymer filaments have been introduced as the support material in packed capillary gas chromatography (GC). The filaments of the heat-resistant polymers, Zylon, Kevlar, Nomex, and Technora, were longitudinally packed into a short fused-silica capillary, followed by the conventional coating process for open-tubular GC columns. The separation of several test mixtures such as n-alkylbenzenes and n-alkanes was carried out with these polymer-coated fiber-packed capillary columns. With the coating by various polymeric materials on the surface of these filaments, the retentivity was significantly improved over the parent fiber-packed column (without polymer coating) as well as a conventional open-tubular capillary of the same length. The results demonstrated a good combination of Zylon as the support and poly(dimethylsiloxane)-based materials as the coating liquid-phase for the successful GC separation of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), while successful applications for other separations such as poly(ethylene glycol) coating for the separation of alcohols were also obtained. From the results it has been suggested that the selectivity of the fiber-packed column could be tuned by selecting different coating materials, indicating the promising possibility for a novel usage of fine fibrous polymers as the support material that can be combined with newly synthesized coating materials specially designed for particular separations. Taking advantage of good thermal stability of the fibers, the column temperature could be elevated to higher than 350 degrees C with the combination of a short metallic capillary. PMID:14710834

  5. 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.

  6. Multipartite secret key distillation and bound entanglement

    SciTech Connect

    Augusiak, Remigiusz; Horodecki, Pawel

    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.

  7. Eruption column physics

    SciTech Connect

    Valentine, G.A.

    1997-03-01

    In this paper the author focuses on the fluid dynamics of large-scale eruption columns. The dynamics of these columns are rooted in multiphase flow phenomena, so a major part of the paper sets up a foundation on that topic that allows one to quickly assess the inherent assumptions made in various theoretical and experimental approaches. The first part is centered on a set of complex differential equations that describe eruption columns, but the focus is on a general understanding of important physical processes rather than on the mathematics. The author discusses briefly the relative merits and weaknesses of different approaches, emphasizing that the largest advances in understanding are made by combining them. He then focuses on dynamics of steady eruption columns and then on transient phenomena. Finally he briefly reviews the effects of varying behavior of the ambient medium through which an eruption column moves. These final sections will emphasize concepts and a qualitative understanding of eruption dynamics. This paper relies on principles of continuum mechanics and transport processes but does not go into detail on the development of those principles. 36 refs., 36 figs., 3 tabs.

  8. 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

  9. Valve packings conquer fugitive emissions

    SciTech Connect

    1995-11-01

    In the early 1990s, when the US Environmental Protection Agency (EPA; Washington, D.C.) declared its intent to regulate fugitive emissions from valve-stem leakage, much of the chemical process industries (CPI) responded with fear and uncertainty. The biggest fear was that valve packing would not meet the required limits on leak rates and that expensive bellows seals may be required on many applications. The uncertainly was about how much it would cost. Today, for the most part, these concerns have been mitigated. It is estimated that about 80--90% of valves satisfy the emission requirements. The rest need some improvement in their packing systems to meet the regulations. Generally, these valves can be brought within compliance if the packing designers follow a few basic principles: Employ less-pliable outer rings and more-pliable inner rings; and don`t use excessive packing. While interest in valve packing remains high, mechanical seals continue to become more user-friendly. Many of those covered below are designed to run dry, and some can even tolerate high shaft-wobble without damage. Also look for improved flange gaskets and a host of seals to protect bearings. Twenty-one summaries are presented on new products and services.

  10. 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...

  11. Fixed Packed Bed Reactors in Reduced Gravity

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    We present experimental data on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed columns in microgravity. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under microgravity conditions compared to 1-g and the widely used Talmor map in 1-g is not applicable for predicting the transition boundaries. A new transition criterion between bubble and pulse flow in microgravity is proposed and tested using the data. Since there is no static head in microgravity, the pressure drop measured is the true frictional pressure drop. The pressure drop data, which has much smaller scatter than most reported 1-g data clearly shows that capillary effects can enhance the pressure drop (especially in the bubble flow regime) as much as 200% compared to that predicted by the single phase Ergun equation. The pressure drop data are correlated in terms of a two-phase friction factor and its dependence on the gas and liquid Reynolds numbers and the Suratman number. The influence of gravity on the pulse amplitude and frequency is also discussed and compared to that under normal gravity conditions. Experimental work is planned to determine the gas-liquid and liquid-solid mass transfer coefficients. Because of enhanced interfacial effects, we expect the gas-liquid transfer coefficients kLa and kGa (where a is the gas-liquid interfacial area) to be higher in microgravity than in normal gravity at the same flow conditions. This will be verified by gas absorption experiments, with and without reaction in the liquid phase, using oxygen, carbon dioxide, water and dilute aqueous amine solutions. The liquid-solid mass transfer coefficient will also be determined in the bubble as well as the pulse flow regimes using solid benzoic acid particles in the packing and measuring their rate of dissolution. The mass transfer coefficients in microgravity will be compared to those in normal gravity cocurrent flow to determine the mass transfer enhancement and propose new mass transfer correlations for two-phase gas-liquid flows through packed beds in microgravity.

  12. Buckling of Liquid Columns

    NASA Astrophysics Data System (ADS)

    Habibi, M.; Rahmani, Y.; Bonn, Daniel; Ribe, N. M.

    2010-02-01

    Under appropriate conditions, a column of viscous liquid falling onto a rigid surface undergoes a buckling instability. Here we show experimentally and theoretically that liquid buckling exhibits a hitherto unsuspected complexity involving three different modes—viscous, gravitational, and inertial—depending on how the viscous forces that resist bending of the column are balanced. We also find that the nonlinear evolution of the buckling exhibits a surprising multistability with three distinct states: steady stagnation flow, “liquid rope coiling,” and a new state in which the column simultaneously folds periodically and rotates about a vertical axis. The transitions among these states are subcritical, leading to a complex phase diagram in which different combinations of states coexist in different regions of the parameter space.

  13. Fundamental Studies on Two-Phase Gas-Liquid Flows Through Packed Beds in Microgravity

    NASA Technical Reports Server (NTRS)

    Balakotaiah, Vemuri; McCready, Mark J.; Motil, Brian J.

    2002-01-01

    In the typical operation of a packed-bed reactor, gas and liquid flow simultaneously through a fixed bed of solid particles. Depending on the application, the particles can be of various shapes and sizes and provide for intimate contact and high rates of transport between the phases needed to sustain chemical or biological reactions. The packing may also serve as either a catalyst or as a support for growing biological material. NASA has flown two of these packed-bed systems in a microgravity environment with limited or no success. The goal of this research is to develop models (with scale-up capability) needed for the design of the physicochemical equipment to carry out these unit operations in microgravity. New insight will also lead to improvements in normal gravity operations. Our initial experiment was flown using an existing KC-135 two-phase flow rig with a modified test section. The test section is a clear polycarbonate rectangular column with a depth of 2.54 cm, a width of 5.08 cm, and 60 cm long. The column was randomly packed with spherical glass beads by slowly dropping the beads into the bed. Even though care was taken in handling the column after it was filled with packing, the alternating high and low gravity cycles with each parabola created a slightly tighter packed bed than is typically reported for this type. By the usual method of comparing the weight difference of a completely dry column versus a column filled with water, the void fraction was found to be .345 for both sizes of beads used. Five flush mounted differential pressure transducers are spaced at even intervals with the first location 4 cm from the inlet port and the subsequent pressure transducers spaced at 13 cm intervals along the column. Differential pressure data was acquired at 1000 Hz to adequately observe pulse formation and characteristics. Visual images of the flow were recorded using a high-speed SVHS system at 500 frames per second. Over 250 different test conditions were evaluated along with a companion set of tests in normal gravity. The flow rates, fluid properties and packing properties were selected to provide a range of several orders-of-magnitude for the important dimensionless parameters. Additional information is included in the original extended abstract.

  14. Cylinder valve packing nut studies

    SciTech Connect

    Blue, S.C.

    1991-12-31

    The design, manufacture, and use of cylinder valve packing nuts have been studied to improve their resistance to failure from stress corrosion cracking. Stress frozen photoelastic models have been analyzed to measure the stress concentrations at observed points of failure. The load effects induced by assembly torque and thermal expansion of stem packing were observed by strain gaging nuts. The effects of finishing operations and heat treatment were studied by the strain gage hole boring and X-ray methods. Modifications of manufacturing and operation practices are reducing the frequency of stress corrosion failures.

  15. Comparison of Advanced Distillation Control Methods, Final Technical Report

    SciTech Connect

    Dr. James B. Riggs

    2000-11-30

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selections for single-ended and dual-composition control, as well as to compare conventional and advanced control approaches. In addition, a simulator of a main fractionator was used to compare the control performance of conventional and advanced control. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that the use of dynamic simulations is required in order to identify the optimum configuration from among the nine possible choices. The optimum configurations were used to evaluate the relative control performance of conventional PI controllers, MPC (Model Predictive Control), PMBC (Process Model-Based Control), and ANN (Artificial Neural Networks) control. It was determined that MPC works best when one product is much more important than the other, while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and MPC. MPC was found to outperform conventional PI control for the main fractionator. MPC was applied to three industrial columns: one at Phillips Petroleum and two at Union Carbide. In each case, MPC was found to significantly outperform PI controls. The major advantage of the MPC controller is its ability to effectively handle a complex set of constraints and control objectives.

  16. Improved micromachined column design and fluidic interconnects for programmed high-temperature gas chromatography separations.

    PubMed

    Gaddes, David; Westland, Jessica; Dorman, Frank L; Tadigadapa, Srinivas

    2014-07-01

    This work focuses on the development and experimental evaluation of micromachined chromatographic columns for use in a commercial gas chromatography (GC) system. A vespel/graphite ferrule based compression sealing technique is presented using which leak-proof fluidic interconnection between the inlet tubing and the microchannel was achieved. This sealing technique enabled separation at temperatures up to 350°C on a ?GC column. This paper reports the first high-temperature separations in microfabricated chromatographic columns at these temperatures. A 2m microfabricated column using a double Archimedean spiral design with a square cross-section of 100?m×100?m has been developed using silicon microfabrication techniques. The microfabricated column was benchmarked against a 2m 100?m diameter commercial column and the performance between the two columns was evaluated in tests performed under identical conditions. High temperature separations of simulated distillation (ASTM2887) and polycyclic aromatic hydrocarbons (EPA8310) were performed using the ?GC column in temperature programmed mode. The demonstrated ?GC column along with the high temperature fixture offers one more solution toward potentially realizing a portable ?GC device for the detection of semi-volatile environmental pollutants and explosives without the thermal limitations reported to date with ?GC columns using epoxy based interconnect technology. PMID:24866564

  17. A Flexible Moisture Content Probe for Unsaturated Soil Column Experiments

    SciTech Connect

    E. D. Mattson; K. E. Baker; C. D. Palmer; J. M Svoboda

    2006-05-01

    A commercially available soil moisture capacitance probe was modified by replacing rigid electrode traces with non-intrusive, flexible circuit board trace electrodes that can be attached to the interior of soil column walls. This new design minimizes soil packing difficulties and potential bias in flow pathways commonly associated with rigid probe installations in column experiments. Testing showed that the modified probe design provides reproducible output independent of sample bulk density. The electrical conductivity of the pore-water solution, however, affects the probe response. For cases where the specific conductance of the pore-water solution is constant, the probe can be calibrated. The flexible electrodes offer a simple means of minimizing sensor intrusion into laboratory soil columns while providing reproducible voltage output that is a function of moisture content.

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.4500 Isopropylamine...

  19. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.4500 Isopropylamine...

  20. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.4500 Isopropylamine...

  1. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.4500 Isopropylamine...

  2. A Column Dispersion Experiment.

    ERIC Educational Resources Information Center

    Corapcioglu, M. Y.; Koroglu, F.

    1982-01-01

    Crushed glass and a Rhodamine B solution are used in a one-dimensional optically scanned column experiment to study the dispersion phenomenon in porous media. Results indicate that the described model gave satisfactory results and that the dispersion process in this experiment is basically convective. (DC)

  3. Columns in Clay

    ERIC Educational Resources Information Center

    Leenhouts, Robin

    2010-01-01

    This article describes a clay project for students studying Greece and Rome. It provides a wonderful way to learn slab construction techniques by making small clay column capitols. With this lesson, students learn architectural vocabulary and history, understand the importance of classical architectural forms and their influence on today's…

  4. Packing of elastic wires in spherical cavities

    E-print Network

    N. Stoop; J. Najafi; F. K. Wittel; M. Habibi; H. J. Herrmann

    2011-05-26

    We investigate the morphologies and maximum packing density of thin wires packed into spherical cavities. Using simulations and experiments, we find that ordered as well as disordered structures emerge, depending on the amount of internal torsion. We find that the highest packing densities are achieved in low torsion packings for large systems, but in high torsion packings for small systems. An analysis of both situations is given in terms of energetics and comparison is made to analytical models of DNA packing in viral capsids.

  5. Thermal analysis for ion-exchange column system

    SciTech Connect

    Lee, S. Y.; King, W. D.

    2012-07-01

    Models have been developed to simulate the thermal characteristics of Crystalline Silico-titanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed, inadvertent column drainage, and loss of active cooling in the column. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. (authors)

  6. Physical extraction of microorganisms from water-saturated, packed sediment.

    PubMed

    Ugolini, Fabio; Schroth, Martin H; Bürgmann, Helmut; Zeyer, Josef

    2014-05-01

    Microbial characterization of aquifers should include samples of both suspended and attached microorganisms (biofilms). We investigated the effect of shear, sonication, and heat on the extraction of microorganisms from water-saturated, packed sediment columns containing established biofilms. Shear was studied by increasing flow velocity of the column eluent, sonication by treating the columns with ultrasound at different power levels, and heat by warming up the column eluent to different temperatures. Effluent cell concentrations were used as a measure of extraction efficiency. Dissolved organic carbon and adenosine tri-phosphate (ATP) concentrations were used to corroborate cell-extraction results. Additionally, ATP was used as an indicator of cell-membrane integrity. Extraction quality was determined by comparing terminal-restriction fragment length polymorphism (T-RFLP) profiles of extracted bacterial communities with destructively sampled sediment-community profiles. Sonication and heat increased the extraction efficiency up to 200-fold and yielded communities comparable to the sediment community. These treatments showed high potential for in-situ application in aquifers. PMID:24961067

  7. Evaluation of 5 µm Superficially Porous Particles for Capillary and Microfluidic LC Columns

    PubMed Central

    Grinias, James P.; Kennedy, Robert T.

    2015-01-01

    Large-size (4–5 µm) superficially porous particles yield lower plate heights (e.g., the minimal reduced plate height or hmin ? 1.5) than fully porous particles of a similar size when packed into large-bore columns. This property allows for better chromatographic performance without the higher pressures required for smaller particles. This study explores the use of such particles in microfluidic LC columns where materials and fitting pressure limits can constrain the size of particle used. The theoretically predicted performance improvements compared to fully porous particles were not demonstrated in capillary columns (with hmin ? 2 for both particle types), in agreement with previous studies that examined smaller superficially porous particles. Microfluidic columns were then compared to capillary columns. Capillary columns significantly outperformed microfluidic columns due to imperfections imposed by microfluidic channel asymmetry and world-to-chip connection at the optimal flow rate; however, superficially porous particles packed in microfluidic LC columns had flatter plate height versus flow rate curves indicating potential for better performance at high reduced velocities.

  8. Fiber separation from distillers dried grains with solubles using a larger elutriation apparatus and use of fiber as a feedstock for corn fiber gum production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an earlier study, the combination of sieving and elutriation (air flow) was found to be effective in separating fiber from distillers dried grains with solubles (DDGS); the elutriation column diameter used was 63 mm. Larger quantities of fractions were needed for carrying out studies on producti...

  9. Wire and Packing Tape Sandwiches

    ERIC Educational Resources Information Center

    Rabinowitz, Sandy

    2009-01-01

    In this article, the author describes how students can combine craft wire with clear packing tape to create a two-dimensional design that can be bent and twisted to create a three-dimensional form. Students sandwich wire designs between two layers of tape. (Contains 1 online resource.)

  10. Ecology and Energy Action Pack.

    ERIC Educational Resources Information Center

    McDonald's Corp., Oak Brook, IL.

    One of five McDonald's Action Packs, these elementary school-level instructional materials are for use as an introduction to existing units of study, supplements to a textbook, or a source of special projects for environmental education. Contents include these six units: Make Your Own Ecology Mini-spinner, Let's Look at a Food Chain, Drip the…

  11. Cs diffusion in local Taiwan laterite with different solution concentration, pH and packing density.

    PubMed

    Wang, Tsing-Hai; Li, Ming-Hsu; Teng, Shi-Ping

    2008-09-01

    In this work we used an "in-diffusion" method to study the effects of pH, solution concentration and packing density on Cs diffusion by packing local Taiwan laterite (LTL) into modified capillary columns with 5mm diameter. These packed columns were first pre-equilibrated with synthetic groundwater (GW) for 3 weeks. The diffusion experiments were then carried out at ambient condition for 2 weeks. Our experimental results showed that the Cs diffusion profile fits Fick's second law very well in given experimental conditions, indicating the validity of modified capillary column method. Generally speaking, Cs diffusion in LTL decreases as the pH increases and as Cs concentration decreases. The apparent diffusion coefficient (D(a)) increases from 5.52 x 10(-12) (10(-7)M) to 2.18 x 10(-11) (10(-3)M)m(2)/s, while the effective diffusion coefficient (D(e)) shows slight variation as the Cs concentration changes. Both the derived D(a) and D(e) values decrease as the pH increases, implying that the diffusion mechanisms of Cs nuclide in alkaline and acid environment are different. In addition, our results show that Cs diffusion is unaffected by the given packing density, indicating the interlaminary space is not the major determinant of Cs adsorption and diffusion in LTL. PMID:18321721

  12. 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.

  13. 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

  14. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... packed” means the plums or prunes are the proper size for the mold or cell compartments in which they are packed, and the molds or cells are filled in such a way that movement is not allowed. (b) Marking....

  15. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling...internal quality, and external appearance and condition of hazelnuts packed in accordance with any of the pack specifications...

  16. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling...internal quality, and external appearance and condition of hazelnuts packed in accordance with any of the pack specifications...

  17. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling...internal quality, and external appearance and condition of hazelnuts packed in accordance with any of the pack specifications...

  18. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling...internal quality, and external appearance and condition of hazelnuts packed in accordance with any of the pack specifications...

  19. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling...internal quality, and external appearance and condition of hazelnuts packed in accordance with any of the pack specifications...

  20. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  1. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  2. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  3. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  4. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  5. Packing Dimension Profiles and Levy Processes

    E-print Network

    Khoshnevisan, Davar; Xiao, Yimin

    2011-01-01

    We extend the concept of packing dimension profiles, due to Falconer and Howroyd (1997) and Howroyd (2001), and use our extension in order to determine the packing dimension of an arbitrary image of a general Levy process.

  6. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a...

  7. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a...

  8. 7 CFR 958.16 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ONIONS GROWN IN CERTAIN DESIGNATED COUNTIES IN IDAHO, AND MALHEUR...Definitions § 958.16 Pack. Pack means a quantity of onions in any type of container and which falls within specific...

  9. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA...984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or...

  10. Ecology of southern ocean pack ice.

    PubMed

    Brierley, Andrew S; Thomas, David N

    2002-01-01

    Around Antarctica the annual five-fold growth and decay of sea ice is the most prominent physical process and has a profound impact on marine life there. In winter the pack ice canopy extends to cover almost 20 million square kilometres--some 8% of the southern hemisphere and an area larger than the Antarctic continent itself (13.2 million square kilometres)--and is one of the largest, most dynamic ecosystems on earth. Biological activity is associated with all physical components of the sea-ice system: the sea-ice surface; the internal sea-ice matrix and brine channel system; the underside of sea ice and the waters in the vicinity of sea ice that are modified by the presence of sea ice. Microbial and microalgal communities proliferate on and within sea ice and are grazed by a wide range of proto- and macrozooplankton that inhabit the sea ice in large concentrations. Grazing organisms also exploit biogenic material released from the sea ice at ice break-up or melt. Although rates of primary production in the underlying water column are often low because of shading by sea-ice cover, sea ice itself forms a substratum that provides standing stocks of bacteria, algae and grazers significantly higher than those in ice-free areas. Decay of sea ice in summer releases particulate and dissolved organic matter to the water column, playing a major role in biogeochemical cycling as well as seeding water column phytoplankton blooms. Numerous zooplankton species graze sea-ice algae, benefiting additionally because the overlying sea-ice ceiling provides a refuge from surface predators. Sea ice is an important nursery habitat for Antarctic krill, the pivotal species in the Southern Ocean marine ecosystem. Some deep-water fish migrate to shallow depths beneath sea ice to exploit the elevated concentrations of some zooplankton there. The increased secondary production associated with pack ice and the sea-ice edge is exploited by many higher predators, with seals, seabirds and whales aggregating there. As a result, much of the Southern Ocean pelagic whaling was concentrated at the edge of the marginal ice zone. The extent and duration of sea ice fluctuate periodically under the influence of global climatic phenomena including the El Niño Southern Oscillation. Life cycles of some associated species may reflect this periodicity. With evidence for climatic warming in some regions of Antarctica, there is concern that ecosystem change may be induced by changes in sea-ice extent. The relative abundance of krill and salps appears to change interannually with sea-ice extent, and in warm years, when salps proliferate, krill are scarce and dependent predators suffer severely. Further research on the Southern Ocean sea-ice system is required, not only to further our basic understanding of the ecology, but also to provide ecosystem managers with the information necessary for the development of strategies in response to short- and medium-term environmental changes in Antarctica. Technological advances are delivering new sampling platforms such as autonomous underwater vehicles that are improving vastly our ability to sample the Antarctic under sea-ice environment. Data from such platforms will enhance greatly our understanding of the globally important Southern Ocean sea-ice ecosystem. PMID:12154613

  11. The entanglement of distillation for gauge theories

    E-print Network

    Van Acoleyen, Karel; Haegeman, Jutho; Marien, Michael; Scholz, Volkher B; Verstraete, Frank

    2015-01-01

    We study the entanglement structure of lattice gauge theories from the local operational point of view, and, similar to Soni and Trivedi (arXiv:1510.07455), we show that the usual entanglement entropy for a spatial bipartition can be written as the sum of an undistillable gauge part and of another part corresponding to the LOCC distillable entanglement, which is obtained by depolarizing the local superselection sectors. We demonstrate that the distillable entanglement is zero for pure abelian gauge theories in the weak coupling limit, while it is in general nonzero for the nonabelian case. We also consider gauge theories with matter, and show in a perturbative approach how area laws -- including a topological correction -- emerge for the distillable entanglement.

  12. 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.

  13. 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.

  14. The entanglement of distillation for gauge theories

    E-print Network

    Karel Van Acoleyen; Nick Bultinck; Jutho Haegeman; Michael Marien; Volkher B. Scholz; Frank Verstraete

    2015-11-13

    We study the entanglement structure of lattice gauge theories from the local operational point of view, and, similar to Soni and Trivedi (arXiv:1510.07455), we show that the usual entanglement entropy for a spatial bipartition can be written as the sum of an undistillable gauge part and of another part corresponding to the LOCC distillable entanglement, which is obtained by depolarizing the local superselection sectors. We demonstrate that the distillable entanglement is zero for pure abelian gauge theories in the weak coupling limit, while it is in general nonzero for the nonabelian case. We also consider gauge theories with matter, and show in a perturbative approach how area laws -- including a topological correction -- emerge for the distillable entanglement.

  15. The entanglement of distillation for gauge theories

    E-print Network

    Karel Van Acoleyen; Nick Bultinck; Jutho Haegeman; Michael Marien; Volkher B. Scholz; Frank Verstraete

    2015-12-01

    We study the entanglement structure of lattice gauge theories from the local operational point of view, and, similar to Soni and Trivedi (arXiv:1510.07455), we show that the usual entanglement entropy for a spatial bipartition can be written as the sum of an undistillable gauge part and of another part corresponding to the LOCC distillable entanglement, which is obtained by depolarizing the local superselection sectors. We demonstrate that the distillable entanglement is zero for pure abelian gauge theories in the weak coupling limit, while it is in general nonzero for the nonabelian case. We also consider gauge theories with matter, and show in a perturbative approach how area laws -- including a topological correction -- emerge for the distillable entanglement.

  16. Entanglement distillation protocols and number theory

    SciTech Connect

    Bombin, H.; Martin-Delgado, M.A.

    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.

  17. 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.

  18. Mathematical modeling of ethanol production by immobilized Zymomonas mobilis in a packed bed fermenter.

    PubMed

    Melick, M R; Karim, M N; Linden, J C; Dale, B E; Mihaltz, P

    1987-02-01

    A mathematical model which describes ethanol production in a packed bed fermenter containing. Zymomonas mobilis entrapped in small spheres of calcium alginate within a packed bed fermenter has been developed. The equations combine simultaneous diffusion and reaction as well as a complex flow pattern to calculate glucose and ethanol profiles in the column type reactor. As part of the study, diffusivity values for glucose and ethanol in cell-loaded calcium alginate were determined. Also a freecell kinetic expression for Z. mobilis at 33 degrees C and ph 6.0 was developed. Comparison of the model with actual experimental results were made showing average deviations of ca. 30-40%. PMID:18576429

  19. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 8 2013-04-01 2013-04-01 false Cold pack. 890.5700 Section 890.5700 Food...Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a device intended for medical...

  20. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 8 2010-04-01 2010-04-01 false Cold pack. 890.5700 Section 890.5700 Food...Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a device intended for medical...

  1. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 8 2011-04-01 2011-04-01 false Cold pack. 890.5700 Section 890.5700 Food...Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a device intended for medical...

  2. Climate Change Action Pack Climate & Habitats

    E-print Network

    Gunawardena, Arunika

    Climate Change Action Pack Climate & Habitats B A C K G R O U DN C H E C K ! Habitat, Food, Water the potential to affect plants,animals and humans around the globe. #12;Climate Change Action Pack 158 Habitat out in shapes of hills, waves, leaves, and berries. #12;Climate Change Action Pack 159 PROCEDURE

  3. Probability and Statistics for Disordered Sphere Packings

    E-print Network

    Picka, Jeffrey

    2007-01-01

    Developing useful physical models based on sphere packings requires that the disorder within each packing be seen as `random' in a very different way from the disorder seen in configurations of points arising from Gibbs processes. Careful consideration of this disorder has deep implications for how sphere packings can be fit to data, and to how a thermodynamics of granular materials can be developed.

  4. 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.

  5. 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.

  6. Multi-temperature gas chromatography using isothermal columns in series. Technical report

    SciTech Connect

    Spencer, W.A.; Rogers, L.B.

    1980-08-11

    A computer-controlled three-oven gas chromatograph having a multi-position stream-switching valve has been used first to divide a wide-boiling mixture of n-alkanes into three cuts and then to fractionate each cut using a packed column at a different temperature. After initial injection of the sample into the highest temperature column, the low boilers were switched to a low temperature oven. Then, the mid-boilers were switched to a column at an intermediate temperature. For routine repetitive analyses, the multi-oven approach offers an attractive alternative.

  7. A study of the effects of column porosity on gradient separations of proteins.

    PubMed

    Urban, Jirí; Jandera, Pavel; Kucerová, Zdenka; van Straten, Marion A; Claessens, Henk A

    2007-10-01

    The type of the stationary phase for reversed-phase liquid chromatography significantly affects the sample elution. Hydrodynamic properties, efficiency and gradient elution of proteins were investigated on five commercial C18 columns with wide-pore totally porous particles, with superficially porous layer particles, non-porous particles and a silica-based monolithic bed. The efficiency in the terms of reduced plate height is higher for low-molecular ethylbenzene than for proteins, but depends on the character of the pores in the individual columns tested. The superficially porous Poroshell and the non-porous Micra columns provide the best efficiency for proteins at high mobile phase flow rates, probably because of similar pore architecture in the stationary phase. The Zorbax column with similar pore architecture as the Poroshell active layer, i.e. narrow pore distribution of wider pores shows better efficiency than the packed column with narrow pores and broad pore distribution. The monolithic column shows lower efficiency for proteins at high flow rates, but it performs better than the broad-pore distribution totally porous particulate columns. Different pore architecture affects also the retention and selectivity for proteins on the individual columns. The retention times on all columns can be predicted using the model for reversed-phase gradient elution developed originally for low-molecular compounds. Consideration of the limited pore volume accessible to the biopolymers has negligible effect on the prediction of retention on the columns packed with non-porous or superficially porous particles, but improves the accuracy of the predicted data for the totally porous columns with broad pore distribution. PMID:17804002

  8. Exogenous factors contributing to column bed heterogeneity: Part 1: Consequences of 'air' injections in liquid chromatography.

    PubMed

    Samuelsson, Jörgen; Fornstedt, Torgny; Shalliker, Andrew

    2015-08-01

    It has been shown that not only the packing homogeneity, but also factors external to the column bed, such as, frits and distributors can have important effects on the column performance. This current communication is the first in a series focusing on the impact of exogenous factors on the column bed heterogeneity. This study is based on several observations by us and others that chromatographic runs often, for technical reasons, include more or less portions of air in the injections. It is therefore extremely important to find out the impact of air on the column performance, the reliability of the results derived from analyses where air was injected, and the effect on the column homogeneity. We used a photographic approach for visualising the air transport phenomena, and found that the air transport through the column is comprised of many different types of transport phenomena, such as laminal flow, viscous fingering like flows, channels and bulbs, and pulsations. More particularly, the air clouds within the column definitely interact in the adsorption, i.e. mobile phase adsorbed to the column surface is displaced. In addition, irrespective of the type of air transport phenomena, the air does not penetrate the column homogeneously. This process is strongly flow dependent. In this work we study air transport both in an analytical scale and a semi-prep column. PMID:26118806

  9. 27 CFR 19.830 - Application of distilled spirits tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...TREASURY LIQUORS DISTILLED SPIRITS PLANTS Production of Vinegar by the Vaporizing Process Administrative and Miscellaneous...distilled spirits produced in or removed from the premises of a vinegar plant in violation of law or this...

  10. 27 CFR 19.322 - Distillates containing extraneous substances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... bonded wine cellar shall be in accordance with the provisions of 27 CFR part 240. (Sec. 201, Pub. L. 85... therein for fermentation of wine to be used as distilling material at the distilled spirits plant...

  11. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels...703 Distillate diesel fuel. (a) Distillate diesel fuels for testing...adequate for proper engine operation. (b...three grades of #2 diesel fuel...

  12. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels...703 Distillate diesel fuel. (a) Distillate diesel fuels for testing...adequate for proper engine operation. (b...three grades of #2 diesel fuel...

  13. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels...703 Distillate diesel fuel. (a) Distillate diesel fuels for testing...adequate for proper engine operation. (b...three grades of #2 diesel fuel...

  14. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels...703 Distillate diesel fuel. (a) Distillate diesel fuels for testing...adequate for proper engine operation. (b...three grades of #2 diesel fuel...

  15. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels...703 Distillate diesel fuel. (a) Distillate diesel fuels for testing...adequate for proper engine operation. (b...three grades of #2 diesel fuel...

  16. Diffusion in Jammed Particle Packs

    NASA Astrophysics Data System (ADS)

    Bolintineanu, Dan S.; Grest, Gary S.; Lechman, Jeremy B.; Silbert, Leonardo E.

    2015-08-01

    Using random walk simulations we explore diffusive transport through monodisperse sphere packings over a range of packing fractions ? in the vicinity of the jamming transition at ?c . Various diffusion properties are computed over several orders of magnitude in both time and packing pressure. Two well-separated regimes of normal "Fickian" diffusion, where the mean squared displacement is linear in time, are observed. The first corresponds to diffusion inside individual spheres, while the latter is the long-time bulk diffusion. The intermediate anomalous diffusion regime and the long-time value of the diffusion coefficient are both shown to be controlled by particle contacts, which in turn depend on proximity to ?c . The time required to recover normal diffusion t* scales as (? -?c)-0.5 and the long-time diffusivity D?˜(? -?c)0.5 , or D?˜1 /t* . It is shown that the distribution of mean first passage times associated with the escape of random walkers between neighboring particles controls both t* and D? in the limit ? ??c.

  17. Adhesive loose packings of small dry particles.

    PubMed

    Liu, Wenwei; Li, Shuiqing; Baule, Adrian; Makse, Hernán A

    2015-08-28

    We explore adhesive loose packings of small dry spherical particles of micrometer size using 3D discrete-element simulations with adhesive contact mechanics and statistical ensemble theory. A dimensionless adhesion parameter (Ad) successfully combines the effects of particle velocities, sizes and the work of adhesion, identifying a universal regime of adhesive packings for Ad > 1. The structural properties of the packings in this regime are well described by an ensemble approach based on a coarse-grained volume function that includes the correlation between bulk and contact spheres. Our theoretical and numerical results predict: (i) an equation of state for adhesive loose packings that appear as a continuation from the frictionless random close packing (RCP) point in the jamming phase diagram and (ii) the existence of an asymptotic adhesive loose packing point at a coordination number Z = 2 and a packing fraction ? = 1/2(3). Our results highlight that adhesion leads to a universal packing regime at packing fractions much smaller than the random loose packing (RLP), which can be described within a statistical mechanical framework. We present a general phase diagram of jammed matter comprising frictionless, frictional, adhesive as well as non-spherical particles, providing a classification of packings in terms of their continuation from the spherical frictionless RCP. PMID:26186271

  18. 21 CFR 184.1848 - Starter distillate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Starter distillate. 184.1848 Section 184.1848 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS...

  19. Chemical composition of distillers grains, a review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, increasing demand for ethanol as a fuel additive and decreasing dependency on fossil fuels have resulted in a dramatic increase in the amount of grains used for ethanol production. Dry-grind is the major process, resulting in distillers dried grains with solubles (DDGS) as a major ...

  20. Distillation Calculations with a Programmable Calculator.

    ERIC Educational Resources Information Center

    Walker, Charles A.; Halpern, Bret L.

    1983-01-01

    Describes a three-step approach for teaching multicomponent distillation to undergraduates, emphasizing patterns of distribution as an aid to understanding the separation processes. Indicates that the second step can be carried out by programmable calculators. (A more complete set of programs for additional calculations is available from the…