WorldWideScience

Sample records for recycle evaporator simulant

  1. DWPF Recycle Evaporator Simulant Tests

    International Nuclear Information System (INIS)

    Stone, M

    2005-01-01

    Testing was performed to determine the feasibility and processing characteristics of an evaporation process to reduce the volume of the recycle stream from the Defense Waste Processing Facility (DWPF). The concentrated recycle would be returned to DWPF while the overhead condensate would be transferred to the Effluent Treatment Plant. Various blends of evaporator feed were tested using simulants developed from characterization of actual recycle streams from DWPF and input from DWPF-Engineering. The simulated feed was evaporated in laboratory scale apparatus to target a 30X volume reduction. Condensate and concentrate samples from each run were analyzed and the process characteristics (foaming, scaling, etc) were visually monitored during each run. The following conclusions were made from the testing: Concentration of the ''typical'' recycle stream in DWPF by 30X was feasible. The addition of DWTT recycle streams to the typical recycle stream raises the solids content of the evaporator feed considerably and lowers the amount of concentration that can be achieved. Foaming was noted during all evaporation tests and must be addressed prior to operation of the full-scale evaporator. Tests were conducted that identified Dow Corning 2210 as an antifoam candidate that warrants further evaluation. The condensate has the potential to exceed the ETP WAC for mercury, silicon, and TOC. Controlling the amount of equipment decontamination recycle in the evaporator blend would help meet the TOC limits. The evaporator condensate will be saturated with mercury and elemental mercury will collect in the evaporator condensate collection vessel. No scaling on heating surfaces was noted during the tests, but splatter onto the walls of the evaporation vessels led to a buildup of solids. These solids were difficult to remove with 2M nitric acid. Precipitation of solids was not noted during the testing. Some of the aluminum present in the recycle streams was converted from gibbsite to

  2. Converting Simulated Sodium-bearing Waste into a Single Solid Waste Form by Evaporation: Laboratory- and Pilot-Scale Test Results on Recycling Evaporator Overheads

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, D.; D. L. Griffith; R. J. Kirkham; L. G. Olson; S. J. Losinski

    2004-01-01

    Conversion of Idaho National Engineering and Environmental Laboratory radioactive sodium-bearing waste into a single solid waste form by evaporation was demonstrated in both flask-scale and pilot-scale agitated thin film evaporator tests. A sodium-bearing waste simulant was adjusted to represent an evaporator feed in which the acid from the distillate is concentrated, neutralized, and recycled back through the evaporator. The advantage to this flowsheet is that a single remote-handled transuranic waste form is produced in the evaporator bottoms without the generation of any low-level mixed secondary waste. However, use of a recycle flowsheet in sodium-bearing waste evaporation results in a 50% increase in remote-handled transuranic volume in comparison to a non-recycle flowsheet.

  3. Defense Waste Processing Facility Recycle Stream Evaporation

    International Nuclear Information System (INIS)

    STONE, MICHAEL

    2006-01-01

    tank farm by eliminating all recycle transfers to the tank farm except a small purge stream. The test program performed by the Savannah River National Laboratory (SRNL) consisted of four phases: (1) Radioactive characterization of the recycle streams, (2) OLI modeling, (3) simulant testing, and (4) radioactive testing. The evaluation determined that the operation of a dedicated recycle evaporator is feasible, but some technical and operational issues must be resolved. These issues are incorporation of the higher solids from the cleaning solution, foaming during the evaporation process, and higher than acceptable levels of mercury, nitrate, I-129, and organic carbon in the condensate for some of the potential recycle streams. This paper will focus on the simulant testing

  4. Evaporation, Rheology, And Vitrification Of A Pretreated Radioactive Hanford Tank 241-AN-104 Sample Mixed With Simulated Law SBS Recycle

    International Nuclear Information System (INIS)

    MARK, CROWDER

    2004-01-01

    This study involved evaporation of the radioactive low activity waste AN-104 pretreated waste and a simulant LAW submerged bed scrubber recycle from Duratek blended at two different volume ratios. The AN104SBS35651 pretreated wastes were then blended with glass former chemicals, GFCs, and a single blend vitrified. The chemical and physical properties, during all phases of blending were characterized per Table 1-1. The AN-104 radioactive waste used for this study was initially characterized at SRNL, Hay 2003, followed by filtration to remove entrained solids, Poirier 2003, and put through ion exchange for cesium removal, Adu-Wusu 2003,. All the test objectives in Table 1-1 are from section 3 of the Test Specification, Sidibe 2003. The test exception listed in Table 1-2 deleted the vitrification objectives for vitrification product analyses and product testing of the AN-104 glass. Therefore, Table 1-1 does not list any vitrification product analyses and product testing objectives

  5. Studying precipitation recycling over the Tibetan Plateau using evaporation-tagging and back-trajectory analysis

    Science.gov (United States)

    Gao, Y.

    2017-12-01

    Regional precipitation recycling (i.e., the contribution of local evaporation to local precipitation) is an important component of water cycle over the Tibetan Plateau (TP). Two methods were used to investigate regional precipitation recycling: 1) tracking of tagged atmospheric water parcels originating from evaporation in a source region (i.e., E-tagging), and 2) back-trajectory approach to track the evaporative sources contributed to precipitation in a specific region. These two methods were applied to Weather Research and Forecasting (WRF) regional climate simulations to quantify the precipitation recycling ratio in the TP for three selected years: climatologically normal, dry and wet year. The simulation region is characterized by high average elevation above 4000 m and complex terrain. The back-trajectory approach is also calculated over three sub-regions over the TP: namely western, northeastern and southeastern TP, and the E-tagging approach could provide recycling-ratio distributions over the whole TP. Three aspects are investigated to characterize the precipitation recycling: annual mean, seasonal variations and spatial distributions. Averaged over the TP, the precipitation recycling ratio estimated by the E-tagging approach is higher than that from the back-trajectory method. The back-trajectory approach uses a precipitation threshold as total precipitation in five days divided by a random number, and this number was set to 500 as a tread off between equilibrium and computational efficiency. Lower recycling ratio derived from the back-trajectory approach is related to the precipitation threshold used. The E-tagging, however, tracks every air parcel of evaporation regardless of the precipitation amount. There is no obvious seasonal variation in the recycling ratio using both methods. The E-tagging approach shows high recycling ratios in the center TP, indicating stronger land-atmospheric interactions than elsewhere.

  6. Precipitation recycling in West Africa - regional modeling, evaporation tagging and atmospheric water budget analysis

    Science.gov (United States)

    Arnault, Joel; Kunstmann, Harald; Knoche, Hans-Richard

    2015-04-01

    Many numerical studies have shown that the West African monsoon is highly sensitive to the state of the land surface. It is however questionable to which extend a local change of land surface properties would affect the local climate, especially with respect to precipitation. This issue is traditionally addressed with the concept of precipitation recycling, defined as the contribution of local surface evaporation to local precipitation. For this study the West African monsoon has been simulated with the Weather Research and Forecasting (WRF) model using explicit convection, for the domain (1°S-21°N, 18°W-14°E) at a spatial resolution of 10 km, for the period January-October 2013, and using ERA-Interim reanalyses as driving data. This WRF configuration has been selected for its ability to simulate monthly precipitation amounts and daily histograms close to TRMM (Tropical Rainfall Measuring Mission) data. In order to investigate precipitation recycling in this WRF simulation, surface evaporation tagging has been implemented in the WRF source code as well as the budget of total and tagged atmospheric water. Surface evaporation tagging consists in duplicating all water species and the respective prognostic equations in the source code. Then, tagged water species are set to zero at the lateral boundaries of the simulated domain (no inflow of tagged water vapor), and tagged surface evaporation is considered only in a specified region. All the source terms of the prognostic equations of total and tagged water species are finally saved in the outputs for the budget analysis. This allows quantifying the respective contribution of total and tagged atmospheric water to atmospheric precipitation processes. The WRF simulation with surface evaporation tagging and budgets has been conducted two times, first with a 100 km2 tagged region (11-12°N, 1-2°W), and second with a 1000 km2 tagged region (7-16°N, 6°W -3°E). In this presentation we will investigate hydro

  7. Lattice-Boltzmann simulations of droplet evaporation

    KAUST Repository

    Ledesma-Aguilar, Rodrigo; Vella, Dominic; Yeomans, Julia M.

    2014-01-01

    © the Partner Organisations 2014. We study the utility and validity of lattice-Boltzmann (LB) simulations to explore droplet evaporation driven by a concentration gradient. Using a binary-fluid lattice-Boltzmann algorithm based on Cahn-Hilliard dynamics, we study the evaporation of planar films and 3D sessile droplets from smooth solid surfaces. Our results show that LB simulations accurately reproduce the classical regime of quasi-static dynamics. Beyond this limit, we show that the algorithm can be used to explore regimes where the evaporative and diffusive timescales are not widely separated, and to include the effect of boundaries of prescribed driving concentration. We illustrate the method by considering the evaporation of a droplet from a solid surface that is chemically patterned with hydrophilic and hydrophobic stripes. This journal is

  8. Lattice-Boltzmann simulations of droplet evaporation

    KAUST Repository

    Ledesma-Aguilar, Rodrigo

    2014-09-04

    © the Partner Organisations 2014. We study the utility and validity of lattice-Boltzmann (LB) simulations to explore droplet evaporation driven by a concentration gradient. Using a binary-fluid lattice-Boltzmann algorithm based on Cahn-Hilliard dynamics, we study the evaporation of planar films and 3D sessile droplets from smooth solid surfaces. Our results show that LB simulations accurately reproduce the classical regime of quasi-static dynamics. Beyond this limit, we show that the algorithm can be used to explore regimes where the evaporative and diffusive timescales are not widely separated, and to include the effect of boundaries of prescribed driving concentration. We illustrate the method by considering the evaporation of a droplet from a solid surface that is chemically patterned with hydrophilic and hydrophobic stripes. This journal is

  9. Phase 1 Testing Results of Immobilization of WTP Effluent Management Facility Evaporator Bottoms Core Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Cozzi, Alex D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-01-05

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it to the LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate, along with entrained, volatile, and semi-volatile metals, such as Hg, As, and Se. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate that get recycled to the melter, and is a key objective of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of earlier tasks was to formulate and prepare a

  10. Engineering work plan for implementing the Process Condensate Recycle Project at the 242-A evaporator

    International Nuclear Information System (INIS)

    Haring, D.S.

    1995-01-01

    The 242-A Evaporator facility is used to reduce the volume of waste stored in the Hanford double shell tanks. This facility uses filtered raw water for cooling, de-entrainment pad sprays, pump seal water, and chemical tank make-up. Some of these uses result in the introduction of filtered raw water into the process, thus increasing the volume of waste requiring evaporation and subsequent treatment by the 200 East Effluent Treatment Facility. The pump seal water and the de-entrainment pad spray systems were identified as candidates for a waste minimization upgrade. This work plan describes the activities associated with the design, installation, testing and initial operation of the process condensate recycle system. Implementation of the process condensate recycle system will permit the use of process condensate in place of raw water for the de-entrainment pad sprays and pump seals. This will reduce the amount of low-level liquid waste and generated during facility operation through source reduction and recycling

  11. Evaporation Of Hanford Waste Treatment Plant Direct Feed Low Activity Waste Effluent Management Facility Core Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Mcclane, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-09-01

    stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfates in the recycled Condensate and is a key outcome of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of this task was to demonstrate evaporation of a simulant of the LAW Melter Off-gas Condensate expected during DFLAW operations, in order to predict the composition of the effluents from the EMF evaporator to aid in planning for their disposition. This document describes the results of that test using the core simulant. This simulant formulation is designated as the “core simulant”; other additives will be included for specific testing, such as volatiles for evaporation or hazardous metals for measuring leaching properties of waste forms. The results indicate that the simulant can easily be concentrated via evaporation. During that the pH adjustment step in simulant preparation, ammonium is quickly converted to ammonia, and most of the ammonia was stripped from the simulated waste and partitioned to the condensate. Additionally, it was found that after concentrating (>12x) and cooling that a small amount of LiF and Na3(SO4)F precipitate out of solution. With the exception of ammonia, analysis of the condensate indicated very low to below detectable levels of many of the constituents in the simulant, yielding very high decontamination factors (DF).

  12. Numerical simulation of a semi-indirect evaporative cooler

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R. Herrero [Departamento de Ingenieria Termica y de Fluidos, Universidad Politecnica de Cartagena, C/Dr. Fleming, s/n (Campus Muralla), 30202 Cartagena, Murcia (Spain)

    2009-11-15

    This paper presents the experimental study and numerical simulation of a semi-indirect evaporative cooler (SIEC), which acts as an energy recovery device in air conditioning systems. The numerical simulation was conducted by applying the CFD software FLUENT implementing a UDF to model evaporation/condensation. The numerical model was validated by comparing the simulation results with experimental data. Experimental data and numerical results agree for the lower relative humidity series but not for higher relative humidity values. (author)

  13. Numerical simulation of droplet evaporation between two circular plates

    International Nuclear Information System (INIS)

    Bam, Hang Jin; Son, Gi Hun

    2015-01-01

    Numerical simulation is performed for droplet evaporation between two circular plates. The flow and thermal characteristics of the droplet evaporation are numerically investigated by solving the conservation equations of mass, momentum, energy and mass fraction in the liquid and gas phases. The liquid-gas interface is tracked by a sharp-interface level-set method which is modified to include the effects of evaporation at the liquid-gas interface and contact angle hysteresis at the liquid-gas-solid contact line. An analytical model to predict the droplet evaporation is also developed by simplifying the mass and vapor fraction equations in the gas phase. The numerical results demonstrate that the 1-D analytical prediction is not applicable to the high rate evaporation process. The effects of plate gap and receding contact angle on the droplet evaporation are also quantified.

  14. Molecular Dynamics Simulations on Evaporation of Droplets with Dissolved Salts

    OpenAIRE

    Jin-Liang Xu; Min Chen; Xiao-Dong Wang; Bing-Bing Wang

    2013-01-01

    Molecular dynamics simulations are used to study the evaporation of water droplets containing either dissolved LiCl, NaCl or KCl salt in a gaseous surrounding (nitrogen) with a constant high temperature of 600 K. The initial droplet has 298 K temperature and contains 1,120 water molecules, 0, 40, 80 or 120 salt molecules. The effects of the salt type and concentration on the evaporation rate are examined. Three stages with different evaporation rates are observed for all cases. In the initial...

  15. Evaporators

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard

    1996-01-01

    Type of evaporators. Regulation. Thermal dimensioning. Determination of pressure loss and heat transfer coefficients.......Type of evaporators. Regulation. Thermal dimensioning. Determination of pressure loss and heat transfer coefficients....

  16. Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, Duane J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, William R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-01-01

    (chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion of tanks and equipment, precipitation of solids, release of ammonia gas vapors, and scale in the tank farm evaporator. Routing this stream to the tank farms does not permanently divert it from recycling into the WTP, only temporarily stores it prior to reprocessing. Testing is normally performed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. The primary parameter of this phase of the test program was measuring the formation of solids during evaporation in order to assess the compatibility of the stream with the evaporator and transfer and storage equipment. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW facility melter offgas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and, thus, the composition will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. This report discusses results of evaporation testing of the simulant. Two conditions were tested, one with the simulant at near neutral pH, and a second at alkaline pH. The neutral pH test is comparable to the conditions in the Hanford Effluent Treatment Facility (ETF) evaporator, although that evaporator operates at near atmospheric pressure and tests were done under vacuum. For the alkaline test, the target pH was based on the tank farm corrosion control program requirements, and the test protocol and equipment was comparable to that

  17. Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    International Nuclear Information System (INIS)

    Adamson, Duane J.; Nash, Charles A.; McCabe, Daniel J.; Crawford, Charles L.; Wilmarth, William R.

    2014-01-01

    (chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion of tanks and equipment, precipitation of solids, release of ammonia gas vapors, and scale in the tank farm evaporator. Routing this stream to the tank farms does not permanently divert it from recycling into the WTP, only temporarily stores it prior to reprocessing. Testing is normally performed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. The primary parameter of this phase of the test program was measuring the formation of solids during evaporation in order to assess the compatibility of the stream with the evaporator and transfer and storage equipment. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW facility melter offgas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and, thus, the composition will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. This report discusses results of evaporation testing of the simulant. Two conditions were tested, one with the simulant at near neutral pH, and a second at alkaline pH. The neutral pH test is comparable to the conditions in the Hanford Effluent Treatment Facility (ETF) evaporator, although that evaporator operates at near atmospheric pressure and tests were done under vacuum. For the alkaline test, the target pH was based on the tank farm corrosion control program requirements, and the test protocol and equipment was comparable to that

  18. Evaporation

    International Nuclear Information System (INIS)

    Delaney, B.T.; Turner, R.J.

    1989-01-01

    Evaporation has long been used as a unit operation in the manufacture of various products in the chemical-process industries. In addition, it is currently being used for the treatment of hazardous wastes such as radioactive liquids and sludges, metal-plating wastes, and other organic and inorganic wastes. Design choice is dependent on the liquid to be evaporated. The three most common types of evaporation equipment are the rising-film, falling-film, and forced-circulation evaporators. The first two rely on boiling heat transfer and the latter relies on flash vaporization. Heat exchangers, flash tanks, and ejectors are common auxiliary equipment items incorporated with evaporator bodies to complete an evaporator system. Properties of the liquid to be evaporated are critical in final selection of an appropriate evaporator system. Since operating costs are a significant factor in overall cost, heat-transfer characteristics and energy requirements are important considerations. Properties of liquids which are critical to the determination of final design include: heat capacity, heat of vaporization, density, thermal conductivity, boiling point rise, and heat-transfer coefficient. Evaporation is an expensive technology, both in terms of capital costs and operating costs. Additionally, mechanical evaporation produces a condensate and a bottoms stream, one or both of which may require further processing or disposal. 3 figs

  19. Modeling and computational simulation of the osmotic evaporation process

    Directory of Open Access Journals (Sweden)

    Freddy Forero Longas

    2016-09-01

    Conclusions: It was found that for the conditions studied the Knudsen diffusion model is most suitable to describe the transfer of water vapor through the hydrophobic membrane. Simulations developed adequately describe the process of osmotic evaporation, becoming a tool for faster economic development of this technology.

  20. Simulation of Diffusive Lithium Evaporation Onto the NSTX Vessel Walls

    International Nuclear Information System (INIS)

    Stotler, D.P.; Skinner, C.H.; Blanchard, W.R.; Krstic, P.S.; Kugel, H.W.; Schneider, H.; Zakharov, L.E.

    2010-01-01

    A model for simulating the diffusive evaporation of lithium into a helium filled NSTX vacuum vessel is described and validated against an initial set of deposition experiments. The DEGAS 2 based model consists of a three-dimensional representation of the vacuum vessel, the elastic scattering process, and a kinetic description of the evaporated atoms. Additional assumptions are required to account for deuterium out-gassing during the validation experiments. The model agrees with the data over a range of pressures to within the estimated uncertainties. Suggestions are made for more discriminating experiments that will lead to an improved model.

  1. Waste Evaporator Accident Simulation Using RELAP5 Computer Code

    International Nuclear Information System (INIS)

    POLIZZI, L.M.

    2004-01-01

    An evaporator is used on liquid waste from processing facilities to reduce the volume of the waste through heating the waste and allowing some of the water to be separated from the waste through boiling. This separation process allows for more efficient processing and storage of liquid waste. Commonly, the liquid waste consists of an aqueous solution of chemicals that over time could induce corrosion, and in turn weaken the tubes in the steam tube bundle of the waste evaporator that are used to heat the waste. This chemically induced corrosion could escalate into a possible tube leakage and/or the severance of a tube(s) in the tube bundle. In this paper, analyses of a waste evaporator system for the processing of liquid waste containing corrosive chemicals are presented to assess the system response to this accident scenario. This accident scenario is evaluated since its consequences can propagate to a release of hazardous material to the outside environment. It is therefore important to ensure that the evaporator system component structural integrity is not compromised, i.e. the design pressure and temperature of the system is not exceeded during the accident transient. The computer code used for the accident simulation is RELAP5-MOD31. The accident scenario analyzed includes a double-ended guillotine break of a tube in the tube bundle of the evaporator. A mitigated scenario is presented to evaluate the excursion of the peak pressure and temperature in the various components of the evaporator system to assess whether the protective actions and controls available are adequate to ensure that the structural integrity of the evaporator system is maintained and that no atmospheric release occurs

  2. Direct numerical simulations of evaporating droplets in turbulence

    Science.gov (United States)

    Palmore, John; Desjardins, Olivier

    2015-11-01

    This work demonstrates direct numerical simulations of evaporating two phase flows, with applications to studying combustion in aircraft engines. Inside the engine, liquid fuel is injected into the combustion chamber where it atomizes into droplets and evaporates. Combustion occurs as the fuel vapor mixes with the surrounding flow of turbulent gas. Understanding combustion, therefore, requires studying evaporation in a turbulent flow and the resulting vapor distribution. We study the problem using a finite volume framework to solve the Navier-Stokes and scalar transport equations under a low-Mach assumption [Desjardins et al., J. Comp. Phys., 2008]. The liquid-gas interface is tracked using a conservative level-set method [Desjardins et al., J. Comp. Phys., 2008] which allows for a sharp reconstruction of the discontinuity across the interface. Special care is taken in the discretization of cells near the liquid-gas interface to ensure the stability and accuracy of the solution. Results are discussed for non-reacting simulations of liquid droplets evaporating into a turbulent field of inert gas.

  3. Modelling, simulating and optimizing boiler heating surfaces and evaporator circuits

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    A model for optimizing the dynamic performance of boiler have been developed. Design variables related to the size of the boiler and its dynamic performance have been defined. The object function to be optimized takes the weight of the boiler and its dynamic capability into account. As constraints...... for the optimization a dynamic model for the boiler is applied. Furthermore a function for the value of the dynamic performance is included in the model. The dynamic models for simulating boiler performance consists of a model for the flue gas side, a model for the evaporator circuit and a model for the drum....... The dynamic model has been developed for the purpose of determining boiler material temperatures and heat transfer from the flue gas side to the water-/steam side in order to simulate the circulation in the evaporator circuit and hereby the water level fluctuations in the drum. The dynamic model has been...

  4. Preparation and evaporation of Hanford Waste treatment plant direct feed low activity waste effluent management facility simulant

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Howe, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-07

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate, LMOGC) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation, and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream involves concentrating the condensate in a new evaporator at the Effluent Management Facility (EMF) and returning it to the LAW melter. The LMOGC stream will contain components, e.g. halides and sulfates, that are volatile at melter temperatures, have limited solubility in glass waste forms, and present a material corrosion concern. Because this stream will recycle within WTP, these components are expected to accumulate in the LMOGC stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfates in the glass and is a key objective of this program. In order to determine the disposition path, it is key to experimentally determine the fate of contaminants. To do this, testing is needed to account for the buffering chemistry of the components, determine the achievable evaporation end point, identify insoluble solids that form, determine the formation and distribution of key regulatoryimpacting constituents, and generate an aqueous stream that can be used in testing of the subsequent immobilization step. This overall program examines the potential treatment and immobilization of the LMOGC stream to enable alternative disposal. The objective of this task was to (1) prepare a simulant of the LAW Melter Off-gas Condensate expected during DFLAW operations, (2) demonstrate evaporation in order to predict the final composition of the effluents from the EMF

  5. Simulation analysis of globally integrated logistics and recycling strategies

    Energy Technology Data Exchange (ETDEWEB)

    Song, S.J.; Hiroshi, K. [Hiroshima Inst. of Tech., Graduate School of Mechanical Systems Engineering, Dept. of In formation and Intelligent Systems Engineering, Hiroshima (Japan)

    2004-07-01

    This paper focuses on the optimal analysis of world-wide recycling activities associated with managing the logistics and production activities in global manufacturing whose activities stretch across national boundaries. Globally integrated logistics and recycling strategies consist of the home country and two free trading economic blocs, NAFTA and ASEAN, where significant differences are found in production and disassembly cost, tax rates, local content rules and regulations. Moreover an optimal analysis of globally integrated value-chain was developed by applying simulation optimization technique as a decision-making tool. The simulation model was developed and analyzed by using ProModel packages, and the results help to identify some of the appropriate conditions required to make well-performed logistics and recycling plans in world-wide collaborated manufacturing environment. (orig.)

  6. RECYCLING NICKEL ELECTROPLATING RINSE WATERS BY LOW TEMPERATURE EVAPORATION AND REVERSE OSMOSIS

    Science.gov (United States)

    Low temperature evaporation and reverse osmosis systems were each evaluated (on a pilot scale) on their respective ability to process rinse water collected from a nickel electroplating operation. Each system offered advantages under specific operating conditions. The low temperat...

  7. Dynamic simulation of a forced circulation evaporating system

    International Nuclear Information System (INIS)

    Lee, J.S.; Lee, K.J.

    1993-01-01

    A dynamic simulation program has been developed to simulate the forced circulation evaporating system of the Kori PWR Power Plant in Korea which is used to treat liquid waste containing boric acid. Energy and mass balances for the vapor and liquid phases are used to describe the interaction among system components such as the vapor body, heater jacket and condenser. In order to simulate entrainment carryover in the sieve tray column and wire mesh pad, Kister's and Carpenter-Othmer's correlations are adopted, respectively. A new correlation formula is also suggested to simulate the geometric effect of the vapor body. A fuzzy heuristic controller and conventional controllers such as P (proportional), PI (proportional-integral) and PID (proportional-integral-derivative) controls are incorporated to observe their responses to a given disturbance. The simulations show good agreement with the real operation data. It is also identified that the vapor velocity or flow rate in the sieve tray column determines the system decontamination factor (DF), and that the longer the vapor body is, the less entrainment carryover occurs out of the vapor body. In addition, the wire mesh pad is identified as maintaining very high deentrainment efficiency even though the vapor velocity may show large fluctuations. With respect to system control, the fuzzy heuristic controller approaches a new steady state faster than conventional controllers. Also the fuzzy controller maintains higher DF during transients and is stronger against time delay in the control components. (Author)

  8. Simulating evaporation of surface atoms of thorium-alloyed tungsten in strong electronic fields

    International Nuclear Information System (INIS)

    Bochkanov, P.V.; Mordyuk, V.S.; Ivanov, Yu.I.

    1984-01-01

    By the Monte Carlo method simulating evaporation of surface atoms of thorium - alloyed tungsten in strong electric fields is realized. The strongest evaporation of surface atoms of pure tungsten as compared with thorium-alloyed tungsten in the contentration range of thorium atoms in tungsten matrix (1.5-15%) is shown. The evaporation rate increases with thorium atoms concentration. Determined is in relative units the surface atoms evaporation rate depending on surface temperature and electric field stront

  9. Numerical simulation of double-pipe condensers and evaporators

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Valladares, O. [Universidad Nacional Autonoma de Mexico, Morelos (Mexico). Centro de Investigacion en Energia; Perez-Segarra, C.D.; Rigola, J. [Universitat Politecnica de Catalunya, Terrassa (Spain). Centre Tecnologic de Transferencia de Calor, Lab. de Termotecnia i Energetica

    2004-09-01

    A detailed one-dimensional steady and transient numerical simulation of the thermal and fluid-dynamic behaviour of double-pipe heat exchangers (evaporators and condensers) has been carried out. The governing equations (continuity, momentum and energy) inside the internal tube and the annulus, together with the energy equation in the internal tube wall, external tube wall and insulation, are solved iteratively in a segregated manner. The discretized governing equations in the zones with fluid flow are efficiently coupled using an implicit step by step method. This formulation requires the use of empirical correlations for the evaluation of convective heat transfer, shear stress and void fraction. An implicit central difference numerical scheme and a line-by-line solver was used in the internal and external tube walls and insulation. A special treatment has been implemented in order to consider transitions (single-phase/two-phase, dry-out,...). All the flow variables (enthalpies, temperatures, pressures, mass fractions, velocities, heat fluxes,...) together with the thermophysical properties are evaluated at each point of the grid in which the domain is discretized. Different numerical aspects and comparisons with analytical and experimental results are presented in order to verify and validate the model. (author)

  10. Laboratory simulation of high-level liquid waste evaporation and storage

    International Nuclear Information System (INIS)

    Anderson, P.A.

    1978-01-01

    The reprocessing of nuclear fuel generates high-level liquid wastes (HLLW) which require interim storage pending solidification. Interim storage facilities are most efficient if the HLLW is evaporated prior to or during the storage period. Laboratory evaporation and storage studies with simulated waste slurries have yielded data which are applicable to the efficient design and economical operation of actual process equipment

  11. Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges

    Energy Technology Data Exchange (ETDEWEB)

    Maingi, R., E-mail: rmaingi@pppl.gov [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Osborne, T.H. [General Atomics, 3550 General Atomics Ct., San Diego, CA 92121 (United States); Bell, M.G.; Bell, R.E.; Boyle, D.P. [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Canik, J.M. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831 (United States); Diallo, A.; Kaita, R.; Kaye, S.M.; Kugel, H.W.; LeBlanc, B.P. [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Sabbagh, S.A. [Applied Physics and Applied Math Dept., Columbia University, New York, NY 10027 (United States); Skinner, C.H. [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Soukhanovskii, V.A. [Lawrence Livermore National Laboratory, 7000 East Ave, PO Box 808, Livermore, CA 94551 (United States)

    2015-08-15

    In this paper, the effects of a pre-discharge lithium evaporation variation on highly shaped discharges in the National Spherical Torus Experiment (NSTX) are documented. Lithium wall conditioning (‘dose’) was routinely applied onto graphite plasma facing components between discharges in NSTX, partly to reduce recycling. Reduced D{sub α} emission from the lower and upper divertor and center stack was observed, as well as reduced midplane neutral pressure; the magnitude of reduction increased with the pre-discharge lithium dose. Improved energy confinement, both raw τ{sub E} and H-factor normalized to scalings, with increasing lithium dose was also observed. At the highest doses, we also observed elimination of edge-localized modes. The midplane edge plasma profiles were dramatically altered, comparable to lithium dose scans at lower shaping, where the strike point was farther from the lithium deposition centroid. This indicates that the benefits of lithium conditioning should apply to the highly shaped plasmas planned in NSTX-U.

  12. Water accounting and vulnerability evaluation (WAVE): considering atmospheric evaporation recycling and the risk of freshwater depletion in water footprinting.

    Science.gov (United States)

    Berger, Markus; van der Ent, Ruud; Eisner, Stephanie; Bach, Vanessa; Finkbeiner, Matthias

    2014-04-15

    Aiming to enhance the analysis of water consumption and resulting consequences along the supply chain of products, the water accounting and vulnerability evaluation (WAVE) model is introduced. On the accounting level, atmospheric evaporation recycling within drainage basins is considered for the first time, which can reduce water consumption volumes by up to 32%. Rather than predicting impacts, WAVE analyzes the vulnerability of basins to freshwater depletion. Based on local blue water scarcity, the water depletion index (WDI) denotes the risk that water consumption can lead to depletion of freshwater resources. Water scarcity is determined by relating annual water consumption to availability in more than 11,000 basins. Additionally, WDI accounts for the presence of lakes and aquifers which have been neglected in water scarcity assessments so far. By setting WDI to the highest value in (semi)arid basins, absolute freshwater shortage is taken into account in addition to relative scarcity. This avoids mathematical artifacts of previous indicators which turn zero in deserts if consumption is zero. As illustrated in a case study of biofuels, WAVE can help to interpret volumetric water footprint figures and, thus, promotes a sustainable use of global freshwater resources.

  13. Direct numerical simulation of 3D particle motion in an evaporating liquid film

    International Nuclear Information System (INIS)

    Hwang, Ho Chan; Son, Gi Hun

    2016-01-01

    A direct numerical simulation method is developed for 3D particle motion in liquid film evaporation. The liquid-gas and fluid-solid interfaces are tracked by a sharp-interface Level-set (LS) method, which includes the effects of evaporation, contact line and solid particles. The LS method is validated through simulation of the interaction between two particles falling in a single-phase fluid. The LS based DNS method is applied to computation of the particle motion in liquid film evaporation to investigate the particle-interface and particle-particle interactions

  14. Development of decommissioning recycle simulator for the rational reuse of dismantled wastes

    International Nuclear Information System (INIS)

    Sakata, Eichi; Ozaki, Sachio; Hironaga, Michihiko; Nishiuchi, Tatsuo

    2002-01-01

    An expert system having a faculty of furnishing motivations for decommissioning planners to establish a rational recycle scenario has been developed and named 'recycle simulator'. This paper presents both a summarized configuration and an algorithm of the proposed system and indicates content of required data-bases and their mutual relations. Finally an instance applying the 'recycle simulator' pointed out some important factors in the reuse of demolished concrete. (author)

  15. Regulatory off-gas analysis from the evaporation of Hanford simulated waste spiked with organic compounds.

    Science.gov (United States)

    Saito, Hiroshi H; Calloway, T Bond; Ferrara, Daro M; Choi, Alexander S; White, Thomas L; Gibson, Luther V; Burdette, Mark A

    2004-10-01

    After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, the remaining low-activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation before being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile, and pesticide compounds and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River National Laboratory. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using U.S. Environmental Protection Agency (EPA) SW-846 Methods. Volatile and light semi-volatile organic compounds (1 mm Hg vapor pressure) in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program (licensed by OLI Systems, Inc.) evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate, and off-gas streams, with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI Environmental Simulation Program model is constrained by available literature data.

  16. Simultaneous ion and neutral evaporation in aqueous nanodrops: experiment, theory, and molecular dynamics simulations.

    Science.gov (United States)

    Higashi, Hidenori; Tokumi, Takuya; Hogan, Christopher J; Suda, Hiroshi; Seto, Takafumi; Otani, Yoshio

    2015-06-28

    We use a combination of tandem ion mobility spectrometry (IMS-IMS, with differential mobility analyzers), molecular dynamics (MD) simulations, and analytical models to examine both neutral solvent (H2O) and ion (solvated Na(+)) evaporation from aqueous sodium chloride nanodrops. For experiments, nanodrops were produced via electrospray ionization (ESI) of an aqueous sodium chloride solution. Two nanodrops were examined in MD simulations: a 2500 water molecule nanodrop with 68 Na(+) and 60 Cl(-) ions (an initial net charge of z = +8), and (2) a 1000 water molecule nanodrop with 65 Na(+) and 60 Cl(-) ions (an initial net charge of z = +5). Specifically, we used MD simulations to examine the validity of a model for the neutral evaporation rate incorporating both the Kelvin (surface curvature) and Thomson (electrostatic) influences, while both MD simulations and experimental measurements were compared to predictions of the ion evaporation rate equation of Labowsky et al. [Anal. Chim. Acta, 2000, 406, 105-118]. Within a single fit parameter, we find excellent agreement between simulated and modeled neutral evaporation rates for nanodrops with solute volume fractions below 0.30. Similarly, MD simulation inferred ion evaporation rates are in excellent agreement with predictions based on the Labowsky et al. equation. Measurements of the sizes and charge states of ESI generated NaCl clusters suggest that the charge states of these clusters are governed by ion evaporation, however, ion evaporation appears to have occurred with lower activation energies in experiments than was anticipated based on analytical calculations as well as MD simulations. Several possible reasons for this discrepancy are discussed.

  17. Simulation of oblique evaporating diesel sprays, and comparison with empirical correlations and simulated straight sprays

    International Nuclear Information System (INIS)

    Chaudhry, I.A.; Mirza, M.R.; Rashid, M.J.

    2010-01-01

    The innovation in software analysis and various available programming facilities have urged the designers at various levels to do indispensable calculations for engine flows. Presently, the 3-D analysis approach is under practice to do simulations for various parameters involving engine operations using various soft wares, 'Fluent' being the trendiest at the moment for CFD modeling. The present work involves CFD modeling of diesel fuel sprays at a specified angle with cylinder axis. Fuel spray modeling includes sub-models for aerodynamic drag, droplet oscillation and distortion, turbulence effects, droplet breakup, evaporation, and droplet collision and coalescence. The data available from existing published work is used to model the fuel spray and the subsequent simulation results are compared to experimental results to test validity of the proposed models. (author)

  18. Evaporation of freely suspended single droplets: experimental, theoretical and computational simulations

    International Nuclear Information System (INIS)

    Hołyst, R; Litniewski, M; Jakubczyk, D; Kolwas, K; Kolwas, M; Kowalski, K; Migacz, S; Palesa, S; Zientara, M

    2013-01-01

    Evaporation is ubiquitous in nature. This process influences the climate, the formation of clouds, transpiration in plants, the survival of arctic organisms, the efficiency of car engines, the structure of dried materials and many other phenomena. Recent experiments discovered two novel mechanisms accompanying evaporation: temperature discontinuity at the liquid–vapour interface during evaporation and equilibration of pressures in the whole system during evaporation. None of these effects has been predicted previously by existing theories despite the fact that after 130 years of investigation the theory of evaporation was believed to be mature. These two effects call for reanalysis of existing experimental data and such is the goal of this review. In this article we analyse the experimental and the computational simulation data on the droplet evaporation of several different systems: water into its own vapour, water into the air, diethylene glycol into nitrogen and argon into its own vapour. We show that the temperature discontinuity at the liquid–vapour interface discovered by Fang and Ward (1999 Phys. Rev. E 59 417–28) is a rule rather than an exception. We show in computer simulations for a single-component system (argon) that this discontinuity is due to the constraint of momentum/pressure equilibrium during evaporation. For high vapour pressure the temperature is continuous across the liquid–vapour interface, while for small vapour pressures the temperature is discontinuous. The temperature jump at the interface is inversely proportional to the vapour density close to the interface. We have also found that all analysed data are described by the following equation: da/dt = P 1 /(a + P 2 ), where a is the radius of the evaporating droplet, t is time and P 1 and P 2 are two parameters. P 1 = −λΔT/(q eff ρ L ), where λ is the thermal conductivity coefficient in the vapour at the interface, ΔT is the temperature difference between the liquid droplet

  19. A new moving boundary model for transient simulation of dry-expansion evaporators

    DEFF Research Database (Denmark)

    Jensen, Jakob Munch; Knudsen, Hans-Jørgen Høgaard

    2002-01-01

    A new moving boundary model is presented for describing the dynamics of dry-expansin evaporators. The model is derived from conservation equations for mass and energy integrated over the two-phase and the superheated region. The new model is numerical fast compared to discretized models and very...... robust to sudden changes in the system. The model is well suited for open loop simulation for system design and model based contol strategies as e.g. optimal LQG (linear quadratic gausian) control. Simulation results for a refrigeration system are shown for different changes in evaporator fan speed...

  20. Waste Heat Recovery and Recycling in Thermal Separation Processes: Distillation, Multi-Effect Evaporation (MEE) and Crystallization Processes

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel A. Dada; Chandrakant B. Panchal; Luke K. Achenie; Aaron Reichl; Chris C. Thomas

    2012-12-03

    Evaporation and crystallization are key thermal separation processes for concentrating and purifying inorganic and organic products with energy consumption over 1,000 trillion Btu/yr. This project focused on a challenging task of recovering low-temperature latent heat that can have a paradigm shift in the way thermal process units will be designed and operated to achieve high-energy efficiency and significantly reduce the carbon footprint as well as water footprint. Moreover, this project has evaluated the technical merits of waste-heat powered thermal heat pumps for recovery of latent heat from distillation, multi-effect evaporation (MEE), and crystallization processes and recycling into the process. The Project Team has estimated the potential energy, economics and environmental benefits with the focus on reduction in CO2 emissions that can be realized by 2020, assuming successful development and commercialization of the technology being developed. Specifically, with aggressive industry-wide applications of heat recovery and recycling with absorption heat pumps, energy savings of about 26.7 trillion Btu/yr have been estimated for distillation process. The direct environmental benefits of this project are the reduced emissions of combustible products. The estimated major reduction in environmental pollutants in the distillation processes is in CO2 emission equivalent to 3.5 billion lbs/year. Energy consumption associated with water supply and treatments can vary between 1,900 kWh and 23,700 kWh per million-gallon water depending on sources of natural waters [US DOE, 2006]. Successful implementation of this technology would significantly reduce the demand for cooling-tower waters, and thereby the use and discharge of water treatment chemicals. The Project Team has also identified and characterized working fluid pairs for the moderate-temperature heat pump. For an MEE process, the two promising fluids are LiNO3+KNO3+NANO3 (53:28:19 ) and LiNO3+KNO3+NANO2

  1. Effect of simulated mechanical recycling processes on the structure and properties of poly(lactic acid).

    Science.gov (United States)

    Beltrán, F R; Lorenzo, V; Acosta, J; de la Orden, M U; Martínez Urreaga, J

    2018-06-15

    The aim of this work is to study the effects of different simulated mechanical recycling processes on the structure and properties of PLA. A commercial grade of PLA was melt compounded and compression molded, then subjected to two different recycling processes. The first recycling process consisted of an accelerated ageing and a second melt processing step, while the other recycling process included an accelerated ageing, a demanding washing process and a second melt processing step. The intrinsic viscosity measurements indicate that both recycling processes produce a degradation in PLA, which is more pronounced in the sample subjected to the washing process. DSC results suggest an increase in the mobility of the polymer chains in the recycled materials; however the degree of crystallinity of PLA seems unchanged. The optical, mechanical and gas barrier properties of PLA do not seem to be largely affected by the degradation suffered during the different recycling processes. These results suggest that, despite the degradation of PLA, the impact of the different simulated mechanical recycling processes on the final properties is limited. Thus, the potential use of recycled PLA in packaging applications is not jeopardized. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The potential environmental gains from recycling waste plastics: Simulation of transferring recycling and recovery technologies to Shenyang, China

    International Nuclear Information System (INIS)

    Chen Xudong; Xi Fengming; Geng Yong; Fujita, Tsuyoshi

    2011-01-01

    Research highlights: → Urban symbiosis creates compatibility of industrial development and waste management. → Mechanical technology leads to more CO 2 emission reduction. → Energy recovery technology leads to more fossil fuel saving. → Clean energy makes recycling technologies cleaner. → Demand management is crucial for realizing potential environmental gains of recycling. - Abstract: With the increasing attention on developing a low-carbon economy, it is necessary to seek appropriate ways on reducing greenhouse gas (GHG) emissions through innovative municipal solid waste management (MSWM), such as urban symbiosis. However, quantitative assessments on the environmental benefits of urban symbiosis, especially in developing countries, are limited because only a limited number of planned synergistic activities have been successful and it is difficult to acquire detailed inventory data from private companies. This paper modifies and applies a two-step simulation system and used it to assess the potential environmental benefits, including the reduction of GHG emissions and saving of fossil fuels, by employing various Japanese plastics recycling/energy-recovery technologies in Shenyang, China. The results showed that among various recycling/energy-recovery technologies, the mechanical waste plastics recycling technology, which produces concrete formwork boards (NF boards), has the greatest potential in terms of reducing GHG emissions (1.66 kg CO 2 e/kg plastics), whereas the technology for the production of refuse plastic fuel (RPF) has the greatest potential on saving fossil fuel consumption (0.77 kgce/kg-plastics). Additional benefits can be gained by applying combined technologies that cascade the utilization of waste plastics. Moreover, the development of clean energy in conjunction with the promotion of new waste plastics recycling programs could contribute to additional reductions in GHG emissions and fossil fuel consumption.

  3. The potential environmental gains from recycling waste plastics: simulation of transferring recycling and recovery technologies to Shenyang, China.

    Science.gov (United States)

    Chen, Xudong; Xi, Fengming; Geng, Yong; Fujita, Tsuyoshi

    2011-01-01

    With the increasing attention on developing a low-carbon economy, it is necessary to seek appropriate ways on reducing greenhouse gas (GHG) emissions through innovative municipal solid waste management (MSWM), such as urban symbiosis. However, quantitative assessments on the environmental benefits of urban symbiosis, especially in developing countries, are limited because only a limited number of planned synergistic activities have been successful and it is difficult to acquire detailed inventory data from private companies. This paper modifies and applies a two-step simulation system and used it to assess the potential environmental benefits, including the reduction of GHG emissions and saving of fossil fuels, by employing various Japanese plastics recycling/energy-recovery technologies in Shenyang, China. The results showed that among various recycling/energy-recovery technologies, the mechanical waste plastics recycling technology, which produces concrete formwork boards (NF boards), has the greatest potential in terms of reducing GHG emissions (1.66 kg CO(2)e/kg plastics), whereas the technology for the production of refuse plastic fuel (RPF) has the greatest potential on saving fossil fuel consumption (0.77 kg ce/kg-plastics). Additional benefits can be gained by applying combined technologies that cascade the utilization of waste plastics. Moreover, the development of clean energy in conjunction with the promotion of new waste plastics recycling programs could contribute to additional reductions in GHG emissions and fossil fuel consumption. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Expansive development of a decommissioning program 'recycle simulator' in nuclear power station

    International Nuclear Information System (INIS)

    Nishiuchi, T.; Ozaki, S.; Hironaga, M.

    2004-01-01

    A decommissioning program 'Recycle Simulator' should be put into practice in careful consideration of both recycle of non-radioactive wastes and reduce of radioactive wastes in the coming circulatory social system. Nevertheless current support systems for decommissioning planning mainly deal with decontamination, safety storage and dismantlement, so-called the prior part of the total decommissioning process. Authors emphasize the necessity of total planning of decommissioning including recycle or reuse of a large amount of demolition materials and are propelling the development of the multi expert system named 'Recycle Simulator'. This paper presents an algorithm of the recycling and reusing scenario of demolition materials and a summarized configuration. 'Recycle Simulator' for the demolished concrete was developed in 2000 and presented at a previous International Conference on Nuclear Engineering. Construction of a supporting multi expert system for the totally planning of decommissioning projects is objected by expansive development of the previous version. 3 main conclusions obtained from this paper are the following. (1) The previously developed expert system was advanced in its estimation function toward the satisfaction of decommissioning planners. (2) The applicability of the system was enlarged to all the radioactive and non-radioactive wastes, demolished metal and concrete products, in a corresponding site of decommissioning. (3) Finally decommissioning recycle simulator was completed in a harmonized unification. (authors)

  5. Thermodynamic simulation and evaluation of sugar refinery evaporators using a steady state modelling approach

    International Nuclear Information System (INIS)

    Lewis, A.E.; Khodabocus, F.; Dhokun, V.; Khalife, M.

    2010-01-01

    In a sugar refinery, the juice is concentrated through evaporation, with the objective of concentrating the juice to syrup as rapidly as possible. Because the heat of vaporization of water is relatively high, the evaporation process can be highly energy intensive, and therefore the economical use of steam is important in the refinery. This paper reports on the development of a simulation model for the evaporation sections of two Mauritian sugar refineries. The first objective was to use the simulation model to carry out an energy balance over the evaporators in order to assess the economy of steam usage over the refinery. The second objective was to examine to what extent a fundamental steady state model, based on thermodynamics (not kinetics) was capable of predicting the material and energy flows in two operating sugar refineries and thereby to evaluate the applicability of the modelling framework. The simulation model was validated using historical data as well as data from the plant DCS system. The simulation results generally correlated well with the measured values, except for one of the evaporators on one refinery. Some suggestions were made as to the cause of the discrepancy. On balance, it was found that both refineries are extremely efficient in terms of steam and equipment usage and that there is not much scope for energy optimisation within the present configuration - nor for much spare steam capacity for an additional refinery. It was also shown that steady state process simulation, using thermodynamic models, can generate a very useful representation of a working refinery. Besides being able to use the model to 'benchmark' the operation and thus evaluate its performance as a whole as well as across individual units, it could also be used to evaluate refinery performance across refineries, nationally as well as globally.

  6. Design Configuration And Simulation Of A Multi Effects Evaporator For A Desalination Plant

    Directory of Open Access Journals (Sweden)

    Ethar Ali

    2015-08-01

    Full Text Available This research is focused on the economic feasibility of using multi-effect evaporators MEV for the production of potable water for the city of Port Sudan the main port of Sudan. Port Sudan city suffers from chronic shortage of potable water. The study has shown that five effect evaporator plant in Port Sudan can produce 1.41106 m3year at a unit cost of 5m3 with a pay-back period of 7 years. A simulation of the MEV has been performed using Aspen Hysys version 7.3 and produced results were very much similar to these obtained manually.

  7. Towards dual recycling with the aid of time and frequency domain simulations

    International Nuclear Information System (INIS)

    Malec, M; Grote, H; Freise, A; Heinzel, G; Strain, K A; Hough, J; Danzmann, K

    2004-01-01

    Dual recycling, the combination of the interferometric techniques of power and signal recycling, allows the improvement of the shot noise limited sensitivity of interferometric gravitational wave detectors. GEO 600 is the first km-scale gravitational wave detector using dual recycling. The hardware installation is completed and dual recycling has become a great challenge in terms of commissioning of GEO 600. Simulations show that lock acquisition of the optical system can only be achieved in certain detector states. Thus as we need to start with a locked detector in such a specific state, an appropriate strategy is needed to change the state of detector operation without losing lock. The basic concepts and first results based on time and frequency domain simulations will be presented in this paper

  8. Bituminization of simulated waste, spent resins, evaporator concentrates and animal ashes by extrusion process

    International Nuclear Information System (INIS)

    Grosche Filho, C.E.; Chandra, U.

    1987-01-01

    The results of the study of bituminization of simulated radwaste - spennt ion-exchange resins, borate evaporator/concentrates and animal ashes, are presented and discussed. Distilled and oxidizer bitumen were used. Characterization of the crude material and simulated wastes-bitumen mixtures of varying weigt composition (30, 40, 50, 60% by weight of dry waste material) was carried out. The asphaltene and parafin contents in the bitumens were also determined. Some additives and were used with an aim to improve the characteristcs of solidified wastes. For leaching studies, granular ion-exchange resins were with Cs - 134 and mixtures of resin-bitumen were prepared. The leaching studies were executed using the IAEA recommendation and the ISO method. A conventional screw-extruder, common in plastic industry, was used determine operational parameters and process difficulties. Mixtures of resin-bitumen and evaporator concentrate-bitumen obtained from differents operational conditions were characterized. (Author) [pt

  9. Development of dynamic simulator for thermosyphon evaporator process with an application

    International Nuclear Information System (INIS)

    Shimizu, Yoshiaki; Tsutsui, Tenson.

    1986-06-01

    A dynamic simulator has been developed for radwaste evaporator system in the Research Reactor Institute of Kyoto University. Under mild assumptions, two-phase flow model of the thermosyphon evaporator was shown to be modelled by a set of ordinary and algebraic equations. Through a structure analysis of such equations, a compact but efficient computer program was realized using FORTRAN computer language. By comparing numerical results with experimental ones, reliability of the model has been examined. Furthermore, mentioning several applications imbedded into the developed simulator, a bi-objective optimal problem was formulated generally, and then solved numerically through a practical procedure. It is expected that such a consideration is helpful for the radwaste management in practice. (author)

  10. Simulation and optimization of continuous extractive fermentation with recycle system

    Science.gov (United States)

    Widjaja, Tri; Altway, Ali; Rofiqah, Umi; Airlangga, Bramantyo

    2017-05-01

    Extractive fermentation is continuous fermentation method which is believed to be able to substitute conventional fermentation method (batch). The recovery system and ethanol refinery will be easier. Continuous process of fermentation will make the productivity increase although the unconverted sugar in continuous fermentation is still in high concentration. In order to make this process more efficient, the recycle process was used. Increasing recycle flow will enhance the probability of sugar to be re-fermented. However, this will make ethanol enter fermentation column. As a result, the accumulated ethanol will inhibit the growth of microorganism. This research aims to find optimum conditions of solvent to broth ratio (S:B) and recycle flow to fresh feed ratio in order to produce the best yield and productivity. This study employed optimization by Hooke Jeeves method using Matlab 7.8 software. The result indicated that optimum condition occured in S: B=2.615 and R: F=1.495 with yield = 50.2439 %.

  11. Production of proteinase A by Saccharomyces cerevisiae in a cell-recycling fermentation system: Experiments and computer simulations

    DEFF Research Database (Denmark)

    Grøn, S.; Biedermann, K.; Emborg, Claus

    1996-01-01

    experimentally and by computer simulations. Experiments and simulations showed that cell mass and product concentration were enhanced by high ratios of recycling. Additional simulations showed that the proteinase A concentration decreased drastically at high dilution rates and the optimal volumetric...... productivities were at high dilution rates just below washout and at high ratios of recycling. Cell-recycling fermentation gave much higher volumetric productivities and stable product concentrations in contrast to simple continuous fermentation....

  12. Numerical simulation of strong evaporation and condensation for plasma-facing materials

    International Nuclear Information System (INIS)

    Kunugi, T.; Yasuda, H.

    1994-01-01

    The thermal response of the divertor plate to the hard plasma disruptions had been analyzed numerically by the two dimensional transient heat transfer code. There are several studies of the vapor shielding effects on the thermal response to the plasma disruption. However, it was pointed out some discrepancies among the numerical results calculated by U.S., EC and Japan for the same disruption conditions by van der Laan. One of the authors studied the sensitivity of some parameters (i.e., the temperature dependency of the thermal properties, an evaporation coefficient and a saturated condensation ratio) of disruption erosion analysis. Though the authors expected that the variations in evaporation models lead to the large variety of the erosion, they gave no significant effects on the surface temperature, the evaporation and melt-layer thickness. In this paper, the authors will describe the development of the numerical simulation codes for the strong evaporation and condensation from the plasma facing materials (PFMs) such as carbon, tungsten and beryllium

  13. Application of direct simulation Monte Carlo method for analysis of AVLIS evaporation process

    International Nuclear Information System (INIS)

    Nishimura, Akihiko

    1995-01-01

    The computation code of the direct simulation Monte Carlo (DSMC) method was developed in order to analyze the atomic vapor evaporation in atomic vapor laser isotope separation (AVLIS). The atomic excitation temperatures of gadolinium atom were calculated for the model with five low lying states. Calculation results were compared with the experiments obtained by laser absorption spectroscopy. Two types of DSMC simulations which were different in inelastic collision procedure were carried out. It was concluded that the energy transfer was forbidden unless the total energy of the colliding atoms exceeds a threshold value. (author)

  14. Numerical simulation research on the optimization for blade shape of rotational supercavitating evaporator

    International Nuclear Information System (INIS)

    Li, Q; Cheng, J P; Zheng, Z Y; Li, F C; Kulagin, V A

    2015-01-01

    Rotational Supercavitating Evaporator (RSCE) has been proposed as a new technology for seawater desalination. However, it lacks systematic researches on the blade shape of RSCE. In this paper, numerical simulations were conducted on the supercavities formed behind two-dimensional (2D) wedge-shaped cavitators of the RSCE. The cavitating flows around the 2D wedge-shaped cavitators with several certain wedge angles varied from 30 to 150 degrees under different cavitation numbers were simulated, and the empirical formulae of supercavity dimensions about cavitation number at corresponding wedge angles were obtained

  15. Steady 3D Numerical Simulation of the Evaporator and Compensation Chamber of a Loop Heat Pipe

    Directory of Open Access Journals (Sweden)

    A. V. Nedayvozov

    2017-01-01

    Full Text Available The paper presents results of a steady three-dimensional numerical simulation of a flat evaporator and compensation chamber (CC of a loop heat pipe (LHP and describes a procedure of the thermal state calculation of the evaporator and the compensation chamber.The LHP is an efficient heat transfer device operating on the principle of evaporation-condensation cycle. It is successfully used in space technology and also to cool the heat-stressed components of electronic devices and computer equipment. The authors carried out a numerical study of the influence of the condensate pipeline length, immersed in water, on the thermal state of the evaporator and the compensation chamber.  The paper shows the influence of the mass forces field on the calculation results. Presents all the numerical studies carried out by the authors for a brass flat evaporator with a thermal load of 80 W. Water is used as a LHP heat-transfer fluid. Fields of temperature, pressure and velocity are presented for each design option.Based on the calculation results, the authors came to the following conclusions:Influence of the mass forces field for the LHP of this type is significant and leads to arising water vortex flow in the condensate pipeline and CC, thereby mixing and equalizing the water temperature in the CC and in the porous element, reducing the maximum temperature of the porous element;The increasing section length of the condensate pipeline in the CC leads to increasing velocity of the heat-transfer fluid in the CC and in the porous element, decreasing mixing zone of the condensate in the CC, and increasing temperature non-uniformity of the porous element.

  16. A critical assessment of capillary condensation and evaporation equations: a computer simulation study.

    Science.gov (United States)

    Wongkoblap, A; Do, D D; Birkett, G; Nicholson, D

    2011-04-15

    Grand Canonical Monte Carlo simulation (GCMC) is used to study the capillary condensation and evaporation of argon adsorption in finite-length carbon cylindrical nanopores. From the simulation results of local density distributions in the radial and axial directions we obtain the contact angle and the core radii just before condensation and just after evaporation. These are then used in the Kelvin equation (evaporation) and Cohan equation (condensation) to obtain the product of surface tension and liquid molar volume. This product is found to be always greater than for the bulk liquid. We test this deviation with pores of different length and radius and find that both affect the derived product of surface tension and liquid molar volume. The implication of this finding is that if the values of surface tension and liquid molar volume of the bulk phase are used in the Kelvin equation the pore radius will be underestimated. For argon adsorption in cylindrical pores we propose that the Kelvin and Cohan equations should be modified to take account of the difference between the fluid in the adsorbed phase in the confined space and that in the bulk phase. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Determination of uranium distribution in the evaporation of simulated Savannah River Site waste

    International Nuclear Information System (INIS)

    Barnes, M.J.; Chandler, G.T.

    1995-01-01

    The results of an experimental program addressing the distribution of uranium in saltcake and supernate for two Savannah River Site waste compositions are presented. Successive batch evaporations were performed on simulated H-Area Modified Purex low-heat and post-aluminum dissolution wastes spiked with depleted uranium. Waste compositions and physical data were obtained for supernate and saltcake samples. For the H-Area Modified Purex low-heat waste, the product saltcake contained 42% of the total uranium from the original evaporator feed solution. However, precipitated solids only accounted for 10% of the original uranium mass; the interstitial liquid within the saltcake matrix contained the remainder of the uranium. In the case of the simulated post-aluminum dissolution waste; the product saltcake contained 68% of the total uranium from the original evaporator feed solution. Precipitated solids accounted for 52% of the original uranium mass; again, the interstitial liquid within the saltcake matrix contained the remainder of the uranium. An understanding of the distribution of uranium between supernatant liquid, saltcake, and sludge is required to develop a material balance for waste processing operations. This information is necessary to address nuclear criticality safety concerns

  18. Interpretation of atom probe tomography data for the intermetallic TiAl+Nb by means of field evaporation simulation

    KAUST Repository

    Boll, Torben; Al-Kassab, Talaat

    2013-01-01

    In this paper simulations of the field evaporation process during field ion microscopy (FIM) and atom probe tomography (APT) are presented and compared with experimental data. The Müller-Schottky-model [1] was extended to include the local atomic

  19. Numerical simulation and field test study of desulfurization wastewater evaporation treatment through flue gas.

    Science.gov (United States)

    Deng, Jia-Jia; Pan, Liang-Ming; Chen, De-Qi; Dong, Yu-Quan; Wang, Cheng-Mu; Liu, Hang; Kang, Mei-Qiang

    2014-01-01

    Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 μm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

  20. Simulation of boiling flow in evaporator of separate type heat pipe with low heat flux

    International Nuclear Information System (INIS)

    Kuang, Y.W.; Wang, Wen; Zhuan, Rui; Yi, C.C.

    2015-01-01

    Highlights: • A boiling flow model in a separate type heat pipe with 65 mm diameter tube. • Nucleate boiling is the dominant mechanism in large pipes at low mass and heat flux. • The two-phase heat transfer coefficient is less sensitive to the total mass flux. - Abstract: The separate type heat pipe heat exchanger is considered to be a potential selection for developing passive cooling spent fuel pool – for the passive pressurized water reactor. This paper simulates the boiling flow behavior in the evaporator of separate type heat pipe, consisting of a bundle of tubes of inner diameter 65 mm. It displays two-phase characteristic in the evaporation section of the heat pipe working in low heat flux. In this study, the two-phase flow model in the evaporation section of the separate type heat pipe is presented. The volume of fluid (VOF) model is used to consider the interaction between the ammonia gas and liquid. The flow patterns and flow behaviors are studied and the agitated bubbly flow, churn bubbly flow are obtained, the slug bubble is likely to break into churn slug or churn froth flow. In addition, study on the heat transfer coefficients indicates that the nucleate boiling is the dominant mechanism in large pipes at low mass and heat flux, with the heat transfer coefficient being less sensitive to the total mass flux

  1. Waste Treatment Plant LAW Evaporation: Antifoam Performance

    International Nuclear Information System (INIS)

    BAICH, MARKA

    2004-01-01

    This report describes the work performed to determine the performance and fate of several commercial antifoams during evaporation of various simulants of Envelope A, B, and C mixed with simulated River Protection Project Waste Treatment Plant (RPP-WTP) recycle streams. Chemical and radiation stability of selected antifoams was also investigated.Contributors to this effort include: Illinois Institute of Technology (IIT), DOW Corning Analytical, and Savannah River Technology Center (SRTC)

  2. Degradation of pre-aged polymers exposed to simulated recycling: properties and thermal stabilities

    Czech Academy of Sciences Publication Activity Database

    Luzuriaga, S.; Kovářová, Jana; Fortelný, Ivan

    2006-01-01

    Roč. 91, č. 6 (2006), s. 1226-1232 ISSN 0141-3910 Institutional research plan: CEZ:AV0Z40500505 Keywords : accelerated weathering * simulated recycling * polyolefins Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.174, year: 2006

  3. Numerical simulation of the temperature effects on the performance of rotational supercavitating evaporator

    International Nuclear Information System (INIS)

    Zheng, Z Y; Cheng, J P; Li, F C; Zhang, M; Li, Q; Kulagin, V A

    2015-01-01

    With the application of supercavitation effect, a novel device named Rotational Supercavitating Evaporator (RSCE) has been designed for desalination. In order to study the effect of temperature on the performance of RSCE and then direct the experimental study on RSCE for the next step, numerical simulations are conducted on the supercavitating flows in RSCE under different temperatures and rotational speeds. The results show that the rotational speed, resistance moment and mechanical energy consumed by the rotational cavitator under the critical state with the largest supercavity, decrease with the increase of temperature. And the area and volume of the supercavity increase exponentially with the increase of temperature under the same rotational speed

  4. Impacts of boreal hydroelectric reservoirs on seasonal climate and precipitation recycling as simulated by the CRCM5: a case study of the La Grande River watershed, Canada

    Science.gov (United States)

    Irambona, C.; Music, B.; Nadeau, D. F.; Mahdi, T. F.; Strachan, I. B.

    2018-02-01

    Located in northern Quebec, Canada, eight hydroelectric reservoirs of a 9782-km2 maximal area cover 6.4% of the La Grande watershed. This study investigates the changes brought by the impoundment of these reservoirs on seasonal climate and precipitation recycling. Two 30-year climate simulations, corresponding to pre- and post-impoundment conditions, were used. They were generated with the fifth-generation Canadian Regional Climate Model (CRCM5), fully coupled to a 1D lake model (FLake). Seasonal temperatures and annual energy budget were generally well reproduced by the model, except in spring when a cold bias, probably related to the overestimation of snow cover, was seen. The difference in 2-m temperature shows that reservoirs induce localized warming in winter (+0.7 ± 0.02 °C) and cooling in the summer (-0.3 ± 0.02 °C). The available energy at the surface increases throughout the year, mostly due to a decrease in surface albedo. Fall latent and sensible heat fluxes are enhanced due to additional energy storage and availability in summer and spring. The changes in precipitation and runoff are within the model internal variability. At the watershed scale, reservoirs induce an additional evaporation of only 5.9 mm year-1 (2%). We use Brubaker's precipitation recycling model to estimate how much of the precipitation is recycled within the watershed. In both simulations, the maximal precipitation recycling occurs in July (less than 6%), indicating weak land-atmosphere coupling. Reservoirs do not seem to affect this coupling, as precipitation recycling only decreased by 0.6% in July.

  5. Bituminization of simulated waste, spent resins, evaporator concentrates and animal ashes by extrusion process

    International Nuclear Information System (INIS)

    Grosche Filho, C.E.; Chandra, U.

    1986-01-01

    The results of the study of simulated radwaste, spent ion-exchange resins, borates/evaporator-concentrates and animal ashes, in bituminized form, are presented and discussed. Distilled and oxidized bitumen were used for characterizing the crude material and simulated wastes-bitumen mixtures of varying weight composition 30, 40, 50, 60% by weight the dry waste material. The asphaltine and parafin contents in the bitumens were determined. Some additives and clays were used aiming best characteristics of solidified wastes. For leaching studies, granular ion-exchange resins were loaded with Cs 134 and mixtures of resins-bitumens were prepared. The leaching studies were executed using the IAEA recommendation and the ISO method. It was used a conventional screw-extruder, used in plastic industry, to determine operational conditions and process difficulties. Mixtures resins-bitumen and concentrate-bitumen in differents operational condition were prepared and analysed. (Author) [pt

  6. Controlled Crystal Grain Growth in Mixed Cation-Halide Perovskite by Evaporated Solvent Vapor Recycling Method for High Efficiency Solar Cells.

    Science.gov (United States)

    Numata, Youhei; Kogo, Atsushi; Udagawa, Yosuke; Kunugita, Hideyuki; Ema, Kazuhiro; Sanehira, Yoshitaka; Miyasaka, Tsutomu

    2017-06-07

    We developed a new and simple solvent vapor-assisted thermal annealing (VA) procedure which can reduce grain boundaries in a perovskite film for fabricating highly efficient perovskite solar cells (PSCs). By recycling of solvent molecules evaporated from an as-prepared perovskite film as a VA vapor source, named the pot-roast VA (PR-VA) method, finely controlled and reproducible device fabrication was achieved for formamidinium (FA) and methylammonium (MA) mixed cation-halide perovskite (FAPbI 3 ) 0.85 (MAPbBr 3 ) 0.15 . The mixed perovskite was crystallized on a low-temperature prepared brookite TiO 2 mesoporous scaffold. When exposed to very dilute solvent vapor, small grains in the perovskite film gradually unified into large grains, resulting in grain boundaries which were highly reduced and improvement of photovoltaic performance in PSC. PR-VA-treated large grain perovskite absorbers exhibited stable photocurrent-voltage performance with high fill factor and suppressed hysteresis, achieving the best conversion efficiency of 18.5% for a 5 × 5 mm 2 device and 15.2% for a 1.0 × 1.0 cm 2 device.

  7. Systematic simulation of a tubular recycle reactor on the basis of pilot plant experiments

    Energy Technology Data Exchange (ETDEWEB)

    Paar, H; Narodoslawsky, M; Moser, A [Technische Univ., Graz (Austria). Inst. fuer Biotechnologie, Mikrobiologie und Abfalltechnologie

    1990-10-10

    Systematic simulatiom may decisively help in development and optimization of bioprocesses. By applying simulation techniques, optimal use can be made of experimental data, decreasing development costs and increasing the accuracy in predicting the behavior of an industrial scale plant. The procedure of the dialogue between simulation and experimental efforts will be exemplified in a case study. Alcoholic fermentation of glucose by zymomonas mobilis bacteria in a gasified turbular recycle reactor was studied first by systematic simulation, using a computer model based solely on literature data. On the base of the results of this simulation, a 0.013 m{sup 3} pilot plant reactor was constructed. The pilot plant experiments, too, were based on the results of the systematic simulation. Simulated and experimental data were well in agreement. The pilot plant experiments reiterated the trends and limits of the process as shown by the simulation results. Data from the pilot plant runs were then used to improve the simulation model. This improved model was subsequently used to simulate the performances of an industrial scale plant. The results of this simulation are presented. They show that the alcohol fermentation in a tubular recycle reactor is potentially advantageous to other reactor configurations, especially to continuous stirred tanks. (orig.).

  8. Mass and heat transfer between evaporation and condensation surfaces: Atomistic simulation and solution of Boltzmann kinetic equation.

    Science.gov (United States)

    Zhakhovsky, Vasily V; Kryukov, Alexei P; Levashov, Vladimir Yu; Shishkova, Irina N; Anisimov, Sergey I

    2018-04-16

    Boundary conditions required for numerical solution of the Boltzmann kinetic equation (BKE) for mass/heat transfer between evaporation and condensation surfaces are analyzed by comparison of BKE results with molecular dynamics (MD) simulations. Lennard-Jones potential with parameters corresponding to solid argon is used to simulate evaporation from the hot side, nonequilibrium vapor flow with a Knudsen number of about 0.02, and condensation on the cold side of the condensed phase. The equilibrium density of vapor obtained in MD simulation of phase coexistence is used in BKE calculations for consistency of BKE results with MD data. The collision cross-section is also adjusted to provide a thermal flux in vapor identical to that in MD. Our MD simulations of evaporation toward a nonreflective absorbing boundary show that the velocity distribution function (VDF) of evaporated atoms has the nearly semi-Maxwellian shape because the binding energy of atoms evaporated from the interphase layer between bulk phase and vapor is much smaller than the cohesive energy in the condensed phase. Indeed, the calculated temperature and density profiles within the interphase layer indicate that the averaged kinetic energy of atoms remains near-constant with decreasing density almost until the interphase edge. Using consistent BKE and MD methods, the profiles of gas density, mass velocity, and temperatures together with VDFs in a gap of many mean free paths between the evaporation and condensation surfaces are obtained and compared. We demonstrate that the best fit of BKE results with MD simulations can be achieved with the evaporation and condensation coefficients both close to unity.

  9. Waste Feed Evaporation Physical Properties Modeling

    International Nuclear Information System (INIS)

    Daniel, W.E.

    2003-01-01

    This document describes the waste feed evaporator modeling work done in the Waste Feed Evaporation and Physical Properties Modeling test specification and in support of the Hanford River Protection Project (RPP) Waste Treatment Plant (WTP) project. A private database (ZEOLITE) was developed and used in this work in order to include the behavior of aluminosilicates such a NAS-gel in the OLI/ESP simulations, in addition to the development of the mathematical models. Mathematical models were developed that describe certain physical properties in the Hanford RPP-WTP waste feed evaporator process (FEP). In particular, models were developed for the feed stream to the first ultra-filtration step characterizing its heat capacity, thermal conductivity, and viscosity, as well as the density of the evaporator contents. The scope of the task was expanded to include the volume reduction factor across the waste feed evaporator (total evaporator feed volume/evaporator bottoms volume). All the physical properties were modeled as functions of the waste feed composition, temperature, and the high level waste recycle volumetric flow rate relative to that of the waste feed. The goal for the mathematical models was to predict the physical property to predicted simulation value. The simulation model approximating the FEP process used to develop the correlations was relatively complex, and not possible to duplicate within the scope of the bench scale evaporation experiments. Therefore, simulants were made of 13 design points (a subset of the points used in the model fits) using the compositions of the ultra-filtration feed streams as predicted by the simulation model. The chemistry and physical properties of the supernate (the modeled stream) as predicted by the simulation were compared with the analytical results of experimental simulant work as a method of validating the simulation software

  10. MATHEMATICAL MODELING AND SIMULATION OF AUTOMATIC CONTROL FOR QUINTUPLE EFFECT EVAPORATION OF CENTRAL SUGAR “EL PALMAR” IN VENEZUELA

    Directory of Open Access Journals (Sweden)

    Lisoviett Pérez Pinto

    2015-04-01

    Full Text Available In this paper, the mathematical modeling and simulation of the automatic control of the quintuple effect of evaporation of a sugar mill “El Palmar” in Venezuela is made. The multiple effect consist of 5 evaporators Robert type, with equal characteristics, connected in series. Starting from the desired operating conditions and control requirements: level in each evaporator vessel, cane syrup concentration and pressure in the fifth evaporator vessel using mass balances, balance on solids for each evaporator and energy to the barometric condenser is present at the output of the fifth vessel, the nonlinear model of the process is obtained, resulting in a system of multiple inputs and multiple outputs, with strong interactions between variables. In the design of the system of the automatic process control, we are interested in maintaining the variables that characterize the performance of it and they are regulated in an operating point; we proceed to linearize the model around an equilibrium point, resulting in a new model in terms of the variables variations around an environment from that point. Then, it is processed the model obtained in terms of input and output relations, based on the characterization of it in terms of variables and transfer relationships in the complex frequency domain. Finally, the evaporation process is simulated, establishing the adequacy of the model to the real process.

  11. Factors affecting the leachability of caesium and strontium from cemented simulant evaporator wastes

    International Nuclear Information System (INIS)

    Lee, D.J.; Brown, D.J.

    1981-08-01

    Leach rates of stable cesium and strontium from a range of simulated evaporator waste/cement formulations have been determined. Important factors in plant operation are assessed for their effect on leach rates. Increasing the curing time and lowering the water/cement ratio has been shown to reduce leach rates by up to a factor of four. Incorporation of additives such as clays and supplementary cementatious materials can reduce leach rates by up to three orders magnitude, and coating the surface of the waste form with a neat cement grout can reduce the cesium leach rate by up to four orders of magnitude. The effects of permeability of the matrix and its cesium absorption capacity on the leach rates have been analysed qualitatively. (U.K.)

  12. Formation of nitrogen-containing oligomers by methylglyoxal and amines in simulated evaporating cloud droplets.

    Science.gov (United States)

    De Haan, David O; Hawkins, Lelia N; Kononenko, Julia A; Turley, Jacob J; Corrigan, Ashley L; Tolbert, Margaret A; Jimenez, Jose L

    2011-02-01

    Reactions of methylglyoxal with amino acids, methylamine, and ammonium sulfate can take place in aqueous aerosol and evaporating cloud droplets. These processes are simulated by drying droplets and bulk solutions of these compounds (at low millimolar and 1 M concentrations, respectively) and analyzing the residuals by scanning mobility particle sizing, nuclear magnetic resonance, aerosol mass spectrometry (AMS), and electrospray ionization MS. The results are consistent with imine (but not diimine) formation on a time scale of seconds, followed by the formation of nitrogen-containing oligomers, methylimidazole, and dimethylimidazole products on a time scale of minutes to hours. Measured elemental ratios are consistent with imidazoles and oligomers being major reaction products, while effective aerosol densities suggest extensive reactions take place within minutes. These reactions may be a source of the light-absorbing, nitrogen-containing oligomers observed in urban and biomass-burning aerosol particles.

  13. Essays of leaching in cemented products containing simulated waste from evaporator concentrated of PWR reactor

    International Nuclear Information System (INIS)

    Haucz, Maria Judite A.; Calabria, Jaqueline A. Almeida; Tello, Cledola Cassia O.; Candido, Francisco Donizete; Seles, Sandro Rogerio Novaes

    2011-01-01

    This paper evaluated the results from leaching resistance essays of cemented products, prepared from three distinct formulations, containing simulated waste of concentrated from the PWR reactor evaporator. The leaching rate is a parameter of qualification of solidified products containing radioactive waste and is determined in accordance with regulation ISO 6961. This procedure evaluates the capacity of transfer organic and inorganic substances presents in the waste through dissolution in the extractor medium. For the case of radioactive waste it is reached the more retention of contaminants in the cemented product, i.e.the lesser value of lixiviation rate. Therefore, this work evaluated among the proposed formulation that one which attend the criterion established in the regulation CNEN-NN-6.09

  14. Molecular dynamics simulations for the motion of evaporative droplets driven by thermal gradients along nanochannels

    KAUST Repository

    Wu, Congmin

    2013-04-04

    For a one-component fluid on a solid substrate, a thermal singularity may occur at the contact line where the liquid-vapor interface intersects the solid surface. Physically, the liquid-vapor interface is almost isothermal at the liquid-vapor coexistence temperature in one-component fluids while the solid surface is almost isothermal for solids of high thermal conductivity. Therefore, a temperature discontinuity is formed if the two isothermal interfaces are of different temperatures and intersect at the contact line. This leads to the so-called thermal singularity. The localized hydrodynamics involving evaporation/condensation near the contact line leads to a contact angle depending on the underlying substrate temperature. This dependence has been shown to lead to the motion of liquid droplets on solid substrates with thermal gradients (Xu and Qian 2012 Phys. Rev. E 85 061603). In the present work, we carry out molecular dynamics (MD) simulations as numerical experiments to further confirm the predictions made from our previous continuum hydrodynamic modeling and simulations, which are actually semi-quantitatively accurate down to the small length scales in the problem. Using MD simulations, we investigate the motion of evaporative droplets in one-component Lennard-Jones fluids confined in nanochannels with thermal gradients. The droplet is found to migrate in the direction of decreasing temperature of solid walls, with a migration velocity linearly proportional to the temperature gradient. This agrees with the prediction of our continuum model. We then measure the effect of droplet size on the droplet motion. It is found that the droplet mobility is inversely proportional to a dimensionless coefficient associated with the total rate of dissipation due to droplet movement. Our results show that this coefficient is of order unity and increases with the droplet size for the small droplets (∼10 nm) simulated in the present work. These findings are in semi

  15. Evaporation and NARS Nitric Acid Mass Balance Summary: 2000--2005

    International Nuclear Information System (INIS)

    Kreutzberg, B.D.; Ames, R.L.; Hansel, K.M.

    2005-01-01

    A compilation of the historical nitric acid processing data for the evaporation and nitric acid recycle system (NARS) in TA-55 has provided general acid mass balance trends, as well as the location of missing information in both the evaporation system and NARS data logs. The data were accumulated during the calendar years 2000 to 2005. After making a number of processing assumptions, the empirical system information was used to create an interactive spreadsheet that predicts, with moderate accuracy, some of the various stream variables for the combined evaporation and acid recycle processes. Empirical data and interactive calculations were compared to an Aspen Plus(trademark) simulation of the process

  16. SIMULATION OF MICROALGAL GROWTH IN A CONTINUOUS PHOTOBIOREACTOR WITH SEDIMENTATION AND PARTIAL BIOMASS RECYCLING

    Directory of Open Access Journals (Sweden)

    C. E. de Farias Silva

    Full Text Available Abstract Microalgae are considered as promising feedstocks for the third generation of biofuels. They are autotrophic organisms with high growth rate and can stock an enormous quantity of lipids (about 20 - 40% of their dried cellular weight. This work was aimed at studying the cultivation of Scenedesmus obliquus in a two-stage system composed of a photobioreactor and a settler to concentrate and partially recycle the biomass as a way to enhance the microalgae cellular productivity. It was attempted to specify by simulation and experimental data a relationship between the recycling rate, kinetic parameters of microalgal growth and photobioreactor operating conditions. Scenedesmus obliquus cells were cultivated in a lab-scale flat-plate reactor, homogenized by aeration, and running in continuous flow with a residence time of 1.66 day. Experimental data for the microalgal growth were used in a semi-empirical simulation model. The best results were obtained for Fw=0.2FI, when R = 1 and kd = 0 and 0.05 day-1, with the biomass production in the reactor varying between 8 g L -1 and 14 g L-1, respectively. The mathematical model fitted to the microalgal growth experimental data was appropriate for predicting the efficiency of the reactor in producing Scenedesmus obliquus cells, establishing a relation between cellular productivity and the minimum recycling rate that must be used in the system.

  17. Molecular Monte Carlo Simulations Using Graphics Processing Units: To Waste Recycle or Not?

    Science.gov (United States)

    Kim, Jihan; Rodgers, Jocelyn M; Athènes, Manuel; Smit, Berend

    2011-10-11

    In the waste recycling Monte Carlo (WRMC) algorithm, (1) multiple trial states may be simultaneously generated and utilized during Monte Carlo moves to improve the statistical accuracy of the simulations, suggesting that such an algorithm may be well posed for implementation in parallel on graphics processing units (GPUs). In this paper, we implement two waste recycling Monte Carlo algorithms in CUDA (Compute Unified Device Architecture) using uniformly distributed random trial states and trial states based on displacement random-walk steps, and we test the methods on a methane-zeolite MFI framework system to evaluate their utility. We discuss the specific implementation details of the waste recycling GPU algorithm and compare the methods to other parallel algorithms optimized for the framework system. We analyze the relationship between the statistical accuracy of our simulations and the CUDA block size to determine the efficient allocation of the GPU hardware resources. We make comparisons between the GPU and the serial CPU Monte Carlo implementations to assess speedup over conventional microprocessors. Finally, we apply our optimized GPU algorithms to the important problem of determining free energy landscapes, in this case for molecular motion through the zeolite LTA.

  18. Using Aspen simulation package to determine solubility of mixed salts in TRU waste evaporator bottoms

    Energy Technology Data Exchange (ETDEWEB)

    Hatchell, J.L.

    1998-03-01

    Nitric acid from plutonium process waste is a candidate for waste minimization by recycling. Process simulation software packages, such as Aspen, are valuable tools to estimate how effective recovery processes can be, however, constants in equations of state for many ionic components are not in their data libraries. One option is to combine single salt solubility`s in the Aspen model for mixed salt system. Single salt solubilities were regressed in Aspen within 0.82 weight percent of literature values. These were combined into a single Aspen model and used in the mixed salt studies. A simulated nitric acid waste containing mixed aluminum, calcium, iron, magnesium and sodium nitrate was tested to determine points of solubility between 25 and 100 C. Only four of the modeled experimental conditions, at 50 C and 75 C, produced a saturated solution. While experimental results indicate that sodium nitrate is the first salt to crystallize out, the Aspen computer model shows that the most insoluble salt, magnesium nitrate, the first salt to crystallize. Possible double salt formation is actually taking place under experimental conditions, which is not captured by the Aspen model.

  19. Simulation of air-heated evaporators using a method of local analysis

    International Nuclear Information System (INIS)

    Parise, J.A.R.; Cartwright, W.G.

    1983-01-01

    The development and application of an analytical method for the performance prediction of air-heated evaporators are presented. A local analysis is employed in which the evaporator is considered as a three dimensional matrix of elementary heat transfer modules. For each element, local film coefficients for both air and the evaporating fluid are determined appropriate to the local conditions, including the two-phase flow regime. An application of the method is considered. (Author) [pt

  20. Dynamical Simulation of Recycling and Particle Fueling in TJ-II Plasmas

    International Nuclear Information System (INIS)

    Lopez-Bruna, D.; Ferreira, J. A.; Tabares, F. L.; Castejon, F.; Guasp, J.

    2007-01-01

    With the aim of improving the calculation tools for transport analysis in TJ-II plasmas, in this work we analyze the simplified model for a kinetic equation that ASTRA uses to calculate the neutral particle distribution in the plasma. Next, we act on the boundary conditions for this kinetic equation (particularly on the neutral density in the plasma boundary) so we can simulate the recycling conditions for the TJ-II in a simple way. With the resulting transport models we can easily analyze the sensibility of these plasmas to the cold gas puffing depending on the recycling conditions. These transport models evidence the problem of density control in the TJ-II. Likewise, we estimate the importance of recycling in the plasmas heated by energetic neutral beam injection. The experimentally observed increments in density when the energetic neutrals are injected would respond, according to the calculations here presented, to a large increment of the neutrals influx that cannot be explained by the beam itself. (Author) 22 refs

  1. Measured and simulated soil water evaporation from four Great Plains soils

    Science.gov (United States)

    The amount of soil water lost during stage one and stage two soil water evaporation is of interest to crop water use modelers. The ratio of measured soil surface temperature (Ts) to air temperature (Ta) was tested as a signal for the transition in soil water evaporation from stage one to stage two d...

  2. Recycling inflow method for simulations of spatially evolving turbulent boundary layers over rough surfaces

    Science.gov (United States)

    Yang, Xiang I. A.; Meneveau, Charles

    2016-01-01

    The technique by Lund et al. to generate turbulent inflow for simulations of developing boundary layers over smooth flat plates is extended to the case of surfaces with roughness elements. In the Lund et al. method, turbulent velocities on a sampling plane are rescaled and recycled back to the inlet as inflow boundary condition. To rescale mean and fluctuating velocities, appropriate length scales need be identified and for smooth surfaces, the viscous scale lν = ν/uτ (where ν is the kinematic viscosity and uτ is the friction velocity) is employed for the inner layer. Different from smooth surfaces, in rough wall boundary layers the length scale of the inner layer, i.e. the roughness sub-layer scale ld, must be determined by the geometric details of the surface roughness elements and the flow around them. In the proposed approach, it is determined by diagnosing dispersive stresses that quantify the spatial inhomogeneity caused by the roughness elements in the flow. The scale ld is used for rescaling in the inner layer, and the boundary layer thickness δ is used in the outer region. Both parts are then combined for recycling using a blending function. Unlike the blending function proposed by Lund et al. which transitions from the inner layer to the outer layer at approximately 0.2δ, here the location of blending is shifted upwards to enable simulations of very rough surfaces in which the roughness length may exceed the height of 0.2δ assumed in the traditional method. The extended rescaling-recycling method is tested in large eddy simulation of flow over surfaces with various types of roughness element shapes.

  3. Interpretation of atom probe tomography data for the intermetallic TiAl+Nb by means of field evaporation simulation

    KAUST Repository

    Boll, Torben

    2013-01-01

    In this paper simulations of the field evaporation process during field ion microscopy (FIM) and atom probe tomography (APT) are presented and compared with experimental data. The Müller-Schottky-model [1] was extended to include the local atomic arrangement on the evaporation process of atoms. This arrangement was described by the sum of the next-neighbor-binding-energies, which differ for an atom of type A, depending on how many A-A, B-B or A-B bonds are present. Thus simulations of APT-data of intermetallic phases become feasible. In this study simulations of L10-TiAl with additions of Nb are compared with experimental data. Certain artifacts, which appear for experimental data are treated as well. © 2012 Elsevier B.V.

  4. Numerical Simulation of Recycled Concrete Using Convex Aggregate Model and Base Force Element Method

    Directory of Open Access Journals (Sweden)

    Yijiang Peng

    2016-01-01

    Full Text Available By using the Base Force Element Method (BFEM on potential energy principle, a new numerical concrete model, random convex aggregate model, is presented in this paper to simulate the experiment under uniaxial compression for recycled aggregate concrete (RAC which can also be referred to as recycled concrete. This model is considered as a heterogeneous composite which is composed of five mediums, including natural coarse aggregate, old mortar, new mortar, new interfacial transition zone (ITZ, and old ITZ. In order to simulate the damage processes of RAC, a curve damage model was adopted as the damage constitutive model and the strength theory of maximum tensile strain was used as the failure criterion in the BFEM on mesomechanics. The numerical results obtained in this paper which contained the uniaxial compressive strengths, size effects on strength, and damage processes of RAC are in agreement with experimental observations. The research works show that the random convex aggregate model and the BFEM with the curve damage model can be used for simulating the relationship between microstructure and mechanical properties of RAC.

  5. Mixing of Process Heels, Process Solutions and Recycle Streams: Small-Scale Simulant

    International Nuclear Information System (INIS)

    Kaplan, D.I.

    2001-01-01

    The overall objective of this small-scale simulant mixing study was to identify the processes within the Hanford Site River Protection Project - Waste Treatment Plant (RPP-WTP) that may generate precipitates and to identify the types of precipitates formed. This information can be used to identify where mixtures of various solutions will cause precipitation of solids, potentially causing operational problems such as fouling equipment or increasing the amount of High Level Waste glass produced. Having this information will help guide protocols for flushing or draining tanks, mixing internal recycle streams, and mixing waste tank supernates. This report contains the discussion and thermodynamic chemical speciation modeling of the raw data

  6. Adaptive Mesh Refinement and High Order Geometrical Moment Method for the Simulation of Polydisperse Evaporating Sprays

    Directory of Open Access Journals (Sweden)

    Essadki Mohamed

    2016-09-01

    Full Text Available Predictive simulation of liquid fuel injection in automotive engines has become a major challenge for science and applications. The key issue in order to properly predict various combustion regimes and pollutant formation is to accurately describe the interaction between the carrier gaseous phase and the polydisperse evaporating spray produced through atomization. For this purpose, we rely on the EMSM (Eulerian Multi-Size Moment Eulerian polydisperse model. It is based on a high order moment method in size, with a maximization of entropy technique in order to provide a smooth reconstruction of the distribution, derived from a Williams-Boltzmann mesoscopic model under the monokinetic assumption [O. Emre (2014 PhD Thesis, École Centrale Paris; O. Emre, R.O. Fox, M. Massot, S. Chaisemartin, S. Jay, F. Laurent (2014 Flow, Turbulence and Combustion 93, 689-722; O. Emre, D. Kah, S. Jay, Q.-H. Tran, A. Velghe, S. de Chaisemartin, F. Laurent, M. Massot (2015 Atomization Sprays 25, 189-254; D. Kah, F. Laurent, M. Massot, S. Jay (2012 J. Comput. Phys. 231, 394-422; D. Kah, O. Emre, Q.-H. Tran, S. de Chaisemartin, S. Jay, F. Laurent, M. Massot (2015 Int. J. Multiphase Flows 71, 38-65; A. Vié, F. Laurent, M. Massot (2013 J. Comp. Phys. 237, 277-310]. The present contribution relies on a major extension of this model [M. Essadki, S. de Chaisemartin, F. Laurent, A. Larat, M. Massot (2016 Submitted to SIAM J. Appl. Math.], with the aim of building a unified approach and coupling with a separated phases model describing the dynamics and atomization of the interface near the injector. The novelty is to be found in terms of modeling, numerical schemes and implementation. A new high order moment approach is introduced using fractional moments in surface, which can be related to geometrical quantities of the gas-liquid interface. We also provide a novel algorithm for an accurate resolution of the evaporation. Adaptive mesh refinement properly scaling on massively

  7. Performance of a wiped film evaporator with simulated high level waste slurries

    International Nuclear Information System (INIS)

    Dierks, R.D.; Bonner, W.F.

    1975-01-01

    The horizontal, reverse taper, wiped film evaporator that was evaluated demonstrated a number of positive characteristics with respect to its applicability in the solidification of nuclear fuel recovery process wastes. Foremost among these is its ability to remove the bulk (80 to 90 percent) of the liquid associated with any of the purex-type high level, intermediate level, or mixed waste slurries. The major disadvantage of the evaporator is its current inability to discharge a product that is low enough in liquid content to avoid sticking to the evaporator discharge nozzle. Also, while the indirect indications of the torque required to turn the rotor and the power drawn by the drive motor are indicative of the liquid content of the discharged product, no reliable correlation has been found to cover all of the possible flow rates and feed stock compositions that the evaporator may be required to handle. In addition, no reliable means has been found to indicate the presence or absence of product flow through the discharge nozzle. The lack of a positive means of moving the product concentrate out of the evaporator and into a high temperature receiver is an undesirable feature of the evaporator. Pulverized glass former, or frit, was added to the evaporator feedstock in a ratio of frit to metal oxides of 2 to 1, and the resulting mixture successfully evaporated to a concentrate containing about 50 percent solids. In general, the performance of the wiped film evaporator evaluated was favorable for its use in a nuclear waste fixation process, however further development of the rotor design, power input, and operating techniques will be required to produce a free flowing solid product

  8. Influence of soil surface structure on simulated infiltration and subsequent evaporation

    International Nuclear Information System (INIS)

    Verplancke, H.; Hartmann, R.; Boodt, M. de

    1983-01-01

    A laboratory rainfall and evaporation experiment was conducted to study the effectiveness of the soil surface structure on infiltration and subsequent evaporation. The stability of the surface layer was improved through the application of synthetic additives such as bituminous emulsion and a prepolymer of polyurea (Uresol). The soil column where the soil surface was treated with a bituminous emulsion shows a decrease in depth of wetting owing to the water repellency of that additive, and consequently an increased runoff. However, the application of Uresol to the surface layer improved the infiltration. The main reason for these differences is that in the untreated soils there is a greater clogging of macropores originating from aggregate breakdown under raindrop impact in the top layer. The evaporation experiment started after all columns were wetted to a similar soil-water content and was carried out in a controlled environmental tunnel. Soil-water content profiles were established during evaporation by means of a fully automatic γ-ray scanner. It appears that in both treatments the cumulative evaporation was less than in the untreated soil. This was due to the effect of an aggregated and stabilized surface layer. Under a treated soil surface the evaporation remains constant during the whole experiment. However, under an untreated soil surface different evaporation stages were recorded. From these experiments the impression is gained that the effect of aggregating the soil surface is an increase of the saturated hydraulic conductivity under conditions near saturation. On the other hand, a finely structured layer exhibits a greater hydraulic conductivity during evaporation in the lower soil-water potential range than a coarsely aggregated layer. So it may be concluded that, to obtain the maximum benefit from the available water - optimal water conservation - much attention must be given to the aggregation of the top soil and its stability. (author)

  9. Recycle Waste Collection Tank (RWCT) simulant testing in the PVTD feed preparation system

    International Nuclear Information System (INIS)

    Abrigo, G.P.; Daume, J.T.; Halstead, S.D.; Myers, R.L.; Beckette, M.R.; Freeman, C.J.; Hatchell, B.K.

    1996-03-01

    (This is part of the radwaste vitrification program at Hanford.) RWCT was to routinely receive final canister decontamination sand blast frit and rinse water, Decontamination Waste Treatment Tank bottoms, and melter off-gas Submerged Bed Scrubber filter cake. In order to address the design needs of the RWCT system to meet performance levels, the PNL Vitrification Technology (PVTD) program used the Feed Preparation Test System (FPTS) to evaluate its equipment and performance for a simulant of RWCT slurry. (FPTS is an adaptation of the Defense Waste Processing Facility feed preparation system and represents the initially proposed Hanford Waste Vitrification Plant feed preparation system designed by Fluor-Daniel, Inc.) The following were determined: mixing performance, pump priming, pump performance, simulant flow characterization, evaporator and condenser performance, and ammonia dispersion. The RWCT test had two runs, one with and one without tank baffles

  10. Capturing the spectrum of interaction effects in genetic association studies by simulated evaporative cooling network analysis.

    Directory of Open Access Journals (Sweden)

    Brett A McKinney

    2009-03-01

    Full Text Available Evidence from human genetic studies of several disorders suggests that interactions between alleles at multiple genes play an important role in influencing phenotypic expression. Analytical methods for identifying Mendelian disease genes are not appropriate when applied to common multigenic diseases, because such methods investigate association with the phenotype only one genetic locus at a time. New strategies are needed that can capture the spectrum of genetic effects, from Mendelian to multifactorial epistasis. Random Forests (RF and Relief-F are two powerful machine-learning methods that have been studied as filters for genetic case-control data due to their ability to account for the context of alleles at multiple genes when scoring the relevance of individual genetic variants to the phenotype. However, when variants interact strongly, the independence assumption of RF in the tree node-splitting criterion leads to diminished importance scores for relevant variants. Relief-F, on the other hand, was designed to detect strong interactions but is sensitive to large backgrounds of variants that are irrelevant to classification of the phenotype, which is an acute problem in genome-wide association studies. To overcome the weaknesses of these data mining approaches, we develop Evaporative Cooling (EC feature selection, a flexible machine learning method that can integrate multiple importance scores while removing irrelevant genetic variants. To characterize detailed interactions, we construct a genetic-association interaction network (GAIN, whose edges quantify the synergy between variants with respect to the phenotype. We use simulation analysis to show that EC is able to identify a wide range of interaction effects in genetic association data. We apply the EC filter to a smallpox vaccine cohort study of single nucleotide polymorphisms (SNPs and infer a GAIN for a collection of SNPs associated with adverse events. Our results suggest an important

  11. RHEOLOGICAL AND ELEMENTAL ANALYSES OF SIMULANT SB5 SLURRY MIX EVAPORATOR-MELTER FEED TANK SLURRIES

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, A.

    2010-02-08

    The Defense Waste Processing Facility (DWPF) will complete Sludge Batch 5 (SB5) processing in fiscal year 2010. DWPF has experienced multiple feed stoppages for the SB5 Melter Feed Tank (MFT) due to clogs. Melter throughput is decreased not only due to the feed stoppage, but also because dilution of the feed by addition of prime water (about 60 gallons), which is required to restart the MFT pump. SB5 conditions are different from previous batches in one respect: pH of the Slurry Mix Evaporator (SME) product (9 for SB5 vs. 7 for SB4). Since a higher pH could cause gel formation, due in part to greater leaching from the glass frit into the supernate, SRNL studies were undertaken to check this hypothesis. The clogging issue is addressed by this simulant work, requested via a technical task request from DWPF. The experiments were conducted at Aiken County Technology Laboratory (ACTL) wherein a non-radioactive simulant consisting of SB5 Sludge Receipt and Adjustment Tank (SRAT) product simulant and frit was subjected to a 30 hour SME cycle at two different pH levels, 7.5 and 10; the boiling was completed over a period of six days. Rheology and supernate elemental composition measurements were conducted. The caustic run exhibited foaming once, after 30 minutes of boiling. It was expected that caustic boiling would exhibit a greater leaching rate, which could cause formation of sodium aluminosilicate and would allow gel formation to increase the thickness of the simulant. Xray Diffraction (XRD) measurements of the simulant did not detect crystalline sodium aluminosilicate, a possible gel formation species. Instead, it was observed that caustic conditions, but not necessarily boiling time, induced greater thickness, but lowered the leach rate. Leaching consists of the formation of metal hydroxides from the oxides, formation of boric acid from the boron oxide, and dissolution of SiO{sub 2}, the major frit component. It is likely that the observed precipitation of Mg

  12. WTP Pilot-Scale Evaporation Tests

    International Nuclear Information System (INIS)

    QURESHI, ZAFAR

    2004-01-01

    This report documents the design, assembly, and operation of a Pilot-Scale Evaporator built and operated by SRTC in support of Waste Treatment Plant (WTP) Project at the DOE's Hanford Site. The WTP employs three identical evaporators, two for the Waste Feed and one for the Treated LAW. The Pilot-Scale Evaporator was designed to test simulants for both of these waste streams. The Pilot-Scale Evaporator is 1/76th scale in terms of evaporation rates. The basic configuration of forced circulation vacuum evaporator was employed. A detailed scaling analysis was performed to preserve key operating parameters such as basic loop configuration, system vacuum, boiling temperature, recirculation rates, vertical distances between important hardware pieces, reboiler heat transfer characteristics, vapor flux, configuration of demisters and water spray rings. Three evaporation test campaigns were completed. The first evaporation run used water in order to shake down the system. The water runs were important in identifying a design flaw that inhibited mixing in the evaporator vessel, thus resulting in unstable boiling operation. As a result the loop configuration was modified and the remaining runs were completed successfully. Two simulant runs followed the water runs. Test 1: Simulated Ultrafiltration Recycles with HLW SBS, and Test 2: Treated AN102 with Envelop C LAW. Several liquid and offgas samples were drawn from the evaporator facility for regulatory and non-regulatory analyses. During Test 2, the feed and the concentrate were spiked with organics to determine organic partitioning. The decontamination factor (DF) for Test 1 was measured to be 110,000 (more than the expected value of 100,000). Dow Corning Q2-3183A antifoam agent was tested during both Tests 1 and 2. It was determined that 500 ppm of this antifoam agent was sufficient to control the foaminess to less than 5 per cent of the liquid height. The long-term testing (around 100 hours of operation) did not show any

  13. Molecular simulation of steady-state evaporation and condensation in the presence of a non-condensable gas

    Science.gov (United States)

    Liang, Zhi; Keblinski, Pawel

    2018-02-01

    Using molecular dynamics simulations, we study evaporation and condensation of fluid Ar in the presence of a non-condensable Ne gas in a nanochannel. The evaporation and condensation are driven by the temperature difference, ΔTL, between the evaporating and condensing liquid surfaces. The steady-state evaporation and condensation fluxes (JMD) are also affected by the Ne concentration, ρNe, and the nanochannel length. We find that across a wide range of ΔTL and ρNe, JMD is in good agreement with the prediction from Stefan's law and from Schrage relationships. Furthermore, for ΔTL less than ˜20% of the absolute average temperature, we find that both steady-state heat and mass fluxes are proportional to ΔTL. This allows us to determine the interfacial resistance to the heat and mass transfer and compare it with the corresponding resistances in the gas phase. In this context, we derive an analytical expression for the effective thermal conductivity of the gas region in the nanochannel and the mass transport interfacial resistance equivalent length, i.e., the length of the nanochannel for which the resistance to the mass flow is the same as the interfacial resistance to the mass flow.

  14. Simulation of a Wall-Bounded Flow using a Hybrid LES/RAS Approach with Turbulence Recycling

    Science.gov (United States)

    Quinlan, Jesse R.; Mcdaniel, James; Baurle, Robert A.

    2012-01-01

    Simulations of a supersonic recessed-cavity flow are performed using a hybrid large-eddy/ Reynolds-averaged simulation approach utilizing an inflow turbulence recycling procedure and hybridized inviscid flux scheme. Calorically perfect air enters the three-dimensional domain at a free stream Mach number of 2.92. Simulations are performed to assess grid sensitivity of the solution, efficacy of the turbulence recycling, and effect of the shock sensor used with the hybridized inviscid flux scheme. Analysis of the turbulent boundary layer upstream of the rearward-facing step for each case indicates excellent agreement with theoretical predictions. Mean velocity and pressure results are compared to Reynolds-averaged simulations and experimental data for each case, and these comparisons indicate good agreement on the finest grid. Simulations are repeated on a coarsened grid, and results indicate strong grid density sensitivity. The effect of turbulence recycling on the solution is illustrated by performing coarse grid simulations with and without inflow turbulence recycling. Two shock sensors, one of Ducros and one of Larsson, are assessed for use with the hybridized inviscid flux reconstruction scheme.

  15. Experimental and theoretical/numerical study of evaporation from shallow pools of organic liquids, at simulated work place conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lennert, Anne Spandet

    1998-04-01

    The rate of evaporation from shallow pools of organic liquids was measured together with the global pollutant concentration distribution in a test chamber simulating work place conditions at room temperature. factorial data cover three liquids with different volatility, three pool geometries, and three room convective velocities in the range usually met in occupational hygiene. The data are compared to 6 semi-empirical correlations for mass tranfer employed in occupational hygiene and to 5 analytical correlations for boundary layer theory derived by the Reynolds analogy to heat transfer. The semi-empirical correlations generally showed a fair agreement for all experimental data, but tended to underestimate the evaporation especially at the lowest air velocity. All analytical correlations strongly underestimated all experimental data. A new simple correlation predicting evaporation rate based on the data was suggested. Three-dimensional CFD-predictions for laminar flow are in fair agreement with the data on the evaporation rates for the experiment that covers three organic compounds, all pool geometries and the two lowest levels of the air velocity. The global pollutant concentration distribution in case of convective air flow cannot be predicted by the model developed by Roach. If knowledge of the evaporation rate and pollutant concentration at some distance from the source were available, the predicted global pollutant concentration distribution by the model suggested by Scheff. offered a fair agreement with observed data. The box model suggested by Sinden generally offered a fair performance but tended to underestimate the pollutant concentration in region close to the source. Preliminary three-dimensional CFD-predictions of the pollutant concentration distribution in the test chamber covering the data with the lowest air velocity were in fair agreement with the average pollutant concentration but overestimated the average velocity. (au) 29 refs.

  16. Simulation of Patterned Glass Film Formation in the Evaporating Colloidal Liquid under IR Heating

    Science.gov (United States)

    Kolegov, K. S.

    2018-02-01

    The paper theoretically studies the method of evaporative lithography in combination with external infrared heating. This method makes it possible to form solid microstructures of the required relief shape as a result of evaporation of the liquid film of the colloidal solution under the mask. The heated particles are sintered easier, so there are no cracks in the obtained structure, unlike the structure obtained employing the standard method of evaporative lithography. The paper puts forward a modification of the mathematical model which allows to describe not only heat and mass transfer at the initial stage of the process, but also the phase transition of colloidal solution into glass. Aqueous latex is taken as an example. The resulting final form of solid film is in good agreement with the experimental data of other authors.

  17. Application of the Forhyd model to simulate net precipitation and intercepted water evaporation in forest canopies in Colombian amazonia

    International Nuclear Information System (INIS)

    Tellez Guio, Patricia; Boschell Villamarin, Francisco; Tobon Marin, Conrado

    2005-01-01

    Hydrologic simulation is a technique, which allows us to understand the relationships among hydrological, biological and ecological variables in an ecosystem. In this research, the FORHYD model is used to simulate the net precipitation and the water intercepted by the canopies of a mature forest, a 30-year old secondary forest, an 18-year old secondary forest, a 5-year old secondary forest, and a shifting cultivation plot, all located in Colombia's amazonia. The model calculates the water budget of the canopy by using the precipitation rates, canopy drainage and evaporation of the water intercepted by the canopy. This paper is the second one in a series of papers reporting the results of the research on the simulation of the hydrological fluxes in three different land use types of Colombian amazonia. The research was carried out in middle Caqueta of Colombian amazonia (northwest amazon basin). The FORHYD model was calibrated and validated by using field observations of the climate, net precipitation (PT), thoughtful (TH) and stem flow (ST), which were monitored during a period of 15 months from March 2001 to June 2002. These observations were used as both input variables and diagnostic variables to probe the model's precision to simulate field observations. Results showed that FORHYD simulates with a good precision the net precipitation and the evaporation of the water intercepted by the canopy. However, the model's precision depends on a good parameterization, which in turn depends on a good database of field observations. The model is a good tool for simulating the hydrological cycle and can be used to simulate critical scenarios of climate variability

  18. The effects of particle recycling on the divertor plasma: A particle-in-cell with Monte Carlo collision simulation

    Science.gov (United States)

    Chang, Mingyu; Sang, Chaofeng; Sun, Zhenyue; Hu, Wanpeng; Wang, Dezhen

    2018-05-01

    A Particle-In-Cell (PIC) with Monte Carlo Collision (MCC) model is applied to study the effects of particle recycling on divertor plasma in the present work. The simulation domain is the scrape-off layer of the tokamak in one-dimension along the magnetic field line. At the divertor plate, the reflected deuterium atoms (D) and thermally released deuterium molecules (D2) are considered. The collisions between the plasma particles (e and D+) and recycled neutral particles (D and D2) are described by the MCC method. It is found that the recycled neutral particles have a great impact on divertor plasma. The effects of different collisions on the plasma are simulated and discussed. Moreover, the impacts of target materials on the plasma are simulated by comparing the divertor with Carbon (C) and Tungsten (W) targets. The simulation results show that the energy and momentum losses of the C target are larger than those of the W target in the divertor region even without considering the impurity particles, whereas the W target has a more remarkable influence on the core plasma.

  19. Heat transfer in an evaporation-condensation system in simulated weightlessness conditions

    Science.gov (United States)

    Bologa, M. K.; Grosu, F. P.; Kozhevnikov, I. V.; Motorin, O. V.; Polikarpov, A. A.

    2017-10-01

    The process of heat transfer in an evaporation-condensation system (ECS) at circulation of dielectric liquid in a closed thermoelectrohydrodynamic (TEHD) loop consisting of an evaporator, a condenser and electrohydrodynamic (EHD) pump for pumping of heat carrier, is considered. Previously, the authors studied the dependence of heat transfer on the angle of rotation of TEHD loop in a vertical plane. The report contains the results of studies of heat transfer at electrohydrodynamic pumping of the heat carrier (8% solution of acetone in Freon 113) in the condenser area by means of EHD pump of “cone-cone” type. All elements of the ECS are arranged in a horizontal plane and the heat transfer from the heater to the condenser without EHD pumping is impossible. A pulsating heat carrier flow mode, depending on the heat input and the voltage applied to the pump, takes place at EHD pumping. As the input power is decreasing the frequency of the coolant pulsations as well as the departure diameter and number of vapour bubbles are also decreasing. At some critical heat input the pulsations disappear and the transition from turbulent mode to the laminar one takes place causing the decrease of the heat transfer coefficient. The increase of the pumping flow rate by raising the voltage applied to the EHD pump, results in a partial suppression of boiling. The maximum intensification of heat transfer is reached at pulsation frequency of 1.25 Hz. The maximum heat flow from the heater was 4.2·104 W/m2. Graphical representation and the physical interpretation of the results, which reflect the essence of the process, are given.

  20. Distributed parameter modeling and simulation for the evaporation system of a controlled circulation boiler based on 3-D combustion monitoring

    International Nuclear Information System (INIS)

    Chu Yuntao; Lou Chun; Cheng Qiang; Zhou Huaichun

    2008-01-01

    In this paper, a dynamic, distributed parameter model for the evaporation system of a controlled circulation boiler was developed. As an essential basis, the 3-D temperature distribution and the average emissivity of the particle phase inside its furnace can be got by a flame image processing technique from multiple, visible flame image detectors in a real-time combustion monitoring system. Then the transient, 2-D radiation flux can be obtained by solving a set of energy balance equations for the water wall elements, which serves as a distributed boundary condition for the dynamic, distributed parameter model proposed for the evaporation system. For large change of the boiler load, two important parameters, the correction factor of equivalent flame emissivity and the coefficient of the steam mass flow rate at the outlet of the drum, were determined using the operation data from a 300 MW boiler. The model was validated by comparing the simulation results for some main steam parameters of the system with those from measurements. Besides that, the transient distributions of the parameters, such as the steam quality and the mass velocity, were predicted by the model. This model can be used for on-line calculation or off-line prediction of the local abnormal phenomena occurring on the water walls, forming an important basis to effectively evaluate the security and the reliability of a power plant boiler

  1. Interaction between the effects of evaporation rate and amount of simulated rainfall on development of the free-living stages of Haemonchus contortus.

    Science.gov (United States)

    O'Connor, Lauren J; Kahn, Lewis P; Walkden-Brown, Stephen W

    2008-08-17

    A factorial experiment (3 x 4 x 2 x 3) was conducted in programmable incubators to investigate interaction between the effects of rainfall amount, rainfall distribution and evaporation rate on development of Haemonchus contortus to L3. Sheep faeces containing H. contortus eggs were incubated on sterilised soil under variable temperatures typical of summer in the Northern Tablelands of NSW, Australia. Simulated rainfall was applied in 1 of 3 amounts (12, 24 or 32 mm) and 4 distributions (a single event on the day after deposition, or the same total amount split in 2, 3 or 4 equal events over 2, 3 or 4 days, respectively). Samples were incubated at either a Low or High rate of evaporation (Low: 2.1-3.4 mm/day and High: 3.8-6.1 mm/day), and faeces and soil were destructively sampled at 4, 7 and 14 days post-deposition. Recovery of L3 from the soil (extra-pellet L3) increased over time (up to 0.52% at day 14) and with each increment of rainfall (12 mm: evaporation rate (0.01%) compared with the Low evaporation rate (0.31%). All rainfall amounts yielded significantly different recoveries of L3 under Low evaporation rates but there was no difference between the 12 and 24 mm treatments under the High evaporation rate. The distribution of simulated rainfall did not significantly affect recovery of infective larvae. Faecal moisture content was positively associated with L3 recovery, as was the ratio of cumulative precipitation and cumulative evaporation (P/E), particularly when measured in the first 4 days post-deposition. The results show that evaporation rate plays a significant role in regulating the influence of rainfall amount on the success of L3 transmission.

  2. Separation of aromatic precipitates from simulated high level radioactive waste by hydrolysis, evaporation and liquid-liquid extraction

    International Nuclear Information System (INIS)

    Young, S.R.; Shah, H.B.; Carter, J.T.

    1991-01-01

    The Defense Waste Processing Facility (DWPF) at the SRS will be the United States' first facility to process High Level radioactive Waste (HLW) into a borosilicate glass matrix. The removal of aromatic precipitates by hydrolysis, evaporation and liquid-liquid extraction will be a key step in the processing of the HLW. This step, titled the Precipitate Hydrolysis Process, has been demonstrated by the Savannah River Laboratory with the Precipitate Hydrolysis Experimental Facility (PHEF). The mission of the PHEF is to demonstrate processing of simulated high level radioactive waste which contains tetraphenylborate precipitates and nitrite. Reduction of nitrite by hydroxylamine nitrate and hydrolysis of the tetraphenylborate by formic acid is discussed. Gaseous production, which is primarily benzene, nitrous oxide and carbon dioxide, has been quantified. Production of high-boiling organic compounds and the accumulation of these organic compounds within the process are addressed

  3. Mathematical modelling and simulation of the operation in sugar and alcohol industry: 2 - evaporation; Modelagem matematica e simulacao das operacoes da industria de acucar e alcool: 2 - evaporacao

    Energy Technology Data Exchange (ETDEWEB)

    Chiappetta, A; Giudici, R; Nascimento, C A.O. do [Sao Paulo Univ., SP (Brazil). Escola Politecnica

    1987-12-31

    A mathematical model is presented for steady-state simulation of multiple-effects evaporators systems used for concentration of sugar solution. The model basis are the fundamental energy and mass balances equations, as well as empirical correlations for the problem being handled. The evaporation system simulation is performed with an executive program which allows different process configurations. For one typical case, some process parameters (volumetric rate and concentration of feed;exhaust steam temperature) influences on syrup concentration and solution temperature were studied. (author) 8 figs., 2 refs.

  4. Bubble column and CFD simulation for chemical recycling of polyethylene terephthalate

    Science.gov (United States)

    Alzuhairi, Mohammed

    2018-05-01

    Computational Fluid Dynamics (CFD) is an important simulation tool, which uses powerful computer to get optimal design in industrial processes. New approach technique of bubble column for three phases has been used with respect to chemical recycling of Polyethylene Terephthalate (PET). The porous ceramic has been used in thin plate (5 mm) with a narrow pore size distribution. Excellent agreement between CFD has been predicted and experimental profiles of hold-up and velocity close to wall have been observed for a column diameter 0.08 m, column height 0.15 m (HD), and superficial gas velocity (VG) 0.05 m/s. The main purpose of the current study is to highlight depolymerization of PET chemically by using the close system of Ethylene Glycol, PET-Catalyzed, and Nitrogen glycolysis process in bubble column of three phases technique by using Nano catalyst, SiO2 with various weight percent (0.01, 0.02, 0.05, 0.1, 0.2, and 0.5) based on PET weight and preheated Nitrogen up to 100° C by extra heater in bubble column reactor. The depolymerization time could be reduced in order to improve heat and mass transfer in comparison with the traditional methods. Little amount not exceeding 0.01% of Nano SiO2 is enough for completing depolymerization. The final product of PET depolymerization has full characterization by FTIR, AFM, CHN tests and has been used as a vital additive for Bitumen, it has been investigated as a moisture-proof, water seepage-proof material, and as a tough resistant to environmental conditions.

  5. Nanojets, Electrospray, and Ion Field Evaporation: Molecular Dynamics Simulations and Laboratory Experiments

    Science.gov (United States)

    2008-07-22

    Eft (d) (otherwise Coulomb fission occurs), and the solute residue diameter is less than the critical diameter at which E\\ = ER(</); i.e., in the...12 / tap " Figure 10. Atomic configurations taken from a molecular dynamics simulation of a 10 nm formamide droplet prior to and after the

  6. Nanojets, Electrospray, and Ion Field Evaporation: Molecular Dynamics Simulations and Laboratory Experiments

    National Research Council Canada - National Science Library

    Luedtke, W. D; Landman, Uzi; Chiu, Y. H; Levandier, D. J; Dressler, R. A; Sok, S; Gordon, M. S

    2008-01-01

    ... experiment and using molecular dynamics (MD) simulations. The electrospray source is operated in a Taylor cone-jet mode, with the nanojet that forms being characterized by high surface-normal electric field strengths in the vicinity of I V/nm...

  7. Simulation of temporal and spatial distribution of required irrigation water by crop models and the pan evaporation coefficient method

    Science.gov (United States)

    Yang, Yan-min; Yang, Yonghui; Han, Shu-min; Hu, Yu-kun

    2009-07-01

    Hebei Plain is the most important agricultural belt in North China. Intensive irrigation, low and uneven precipitation have led to severe water shortage on the plain. This study is an attempt to resolve this crucial issue of water shortage for sustainable agricultural production and water resources management. The paper models distributed regional irrigation requirement for a range of cultivated crops on the plain. Classic crop models like DSSAT- wheat/maize and COTTON2K are used in combination with pan-evaporation coefficient method to estimate water requirements for wheat, corn, cotton, fruit-trees and vegetables. The approach is more accurate than the static approach adopted in previous studies. This is because the combination use of crop models and pan-evaporation coefficient method dynamically accounts for irrigation requirement at different growth stages of crops, agronomic practices, and field and climatic conditions. The simulation results show increasing Required Irrigation Amount (RIA) with time. RIA ranges from 5.08×109 m3 to 14.42×109 m3 for the period 1986~2006, with an annual average of 10.6×109 m3. Percent average water use by wheat, fruit trees, vegetable, corn and cotton is 41%, 12%, 12%, 11%, 7% and 17% respectively. RIA for April and May (the period with the highest irrigation water use) is 1.78×109 m3 and 2.41×109 m3 respectively. The counties in the piedmont regions of Mount Taihang have high RIA while the central and eastern regions/counties have low irrigation requirement.

  8. Application of High Performance Computing for Simulations of N-Dodecane Jet Spray with Evaporation

    Science.gov (United States)

    2016-11-01

    is unlimited. 10 6. References 1. Malbec L-M, Egúsquiza J, Bruneaux G, Meijer M. Characterization of a set of ECN spray A injectors : nozzle to...sprays and develop a predictive theory for comparison to measurements in the laboratory of turbulent diesel sprays. 15. SUBJECT TERMS high...models into future simulations of turbulent jet sprays and develop a predictive theory for comparison to measurements in the lab of turbulent diesel

  9. Recycling Resources. [Student Handbook, Sound Filmstrips, 12-Inch Record, Pollution Simulation Game, Teacher's Manual

    Science.gov (United States)

    Hatch, C. Richard

    A 15- to 20-hour course on materials recycling, teaching junior high school students about environmental problems and solutions, is developed in this set of materials. It attempts to stimulate them to participate in community efforts aimed at improving the environment. Items in the kit include: (1) teacher's manual, with lesson plans enumerating…

  10. Numerical simulations of multicomponent evaporation and gas-phase transport using M{sup 2}NOTS

    Energy Technology Data Exchange (ETDEWEB)

    Ho, C.K. [Sandia National Laboratories, Albuquerque, NM (United States)

    1995-03-01

    The multiphase, multicomponent, non-isothermal simulator M{sup 2}NOTS was tested against several one-dimensional experiments. The experiments represented a through-flow limiting condition of soil venting in which air flows through the contaminated region. Predictions using M{sup 2}NOTS of changing in situ compositions and effluent concentrations for toluene and o-xylene mixtures were compared to the observed results. Results showed that M{sup 2}NOTS was able to capture the salient trends and features of multicomponent through-flow venting processes.

  11. A simulation environment for dry-expansion evaporators with application to the design of autotuning control algorithms for electronic expansion valves

    Energy Technology Data Exchange (ETDEWEB)

    Beghi, Alessandro [Dipartimento di Ingegneria dell' Informazione, Universita di Padova, via Gradenigo 6/B, I-35131 Padova (Italy); Cecchinato, Luca [Dipartimento di Fisica Tecnica, Universita di Padova, via Venezia 1, I-35131 Padova (Italy)

    2009-11-15

    In this paper some results of a research project aimed at deriving high-performance, adaptive control algorithms for electronic expansion valves (EEVs) to be used in finned-coiled, dry-expansion evaporators for refrigeration systems are reported. With the aim of developing a software environment that can be used for controller design, rapid prototyping, optimization of data collection and test design, virtual prototyping approach to design was adopted. The development of a distributed dynamic simulation model of the evaporator coupled with an electronic expansion valve, and its use for deriving autotuning PID control algorithms is described. Experimental results confirm the effectiveness of this kind of approach. (author)

  12. Flash evaporator

    OpenAIRE

    1997-01-01

    A device and method for flash evaporating a reagent includes an evaporation chamber that houses a dome on which evaporation occurs. The dome is solid and of high thermal conductivity and mass, and may be heated to a temperature sufficient to vaporize a specific reagent. The reagent is supplied from an external source to the dome through a nozzle, and may be supplied as a continuous stream, as a shower, and as discrete drops. A carrier gas may be introduced into the evaporation chamber and cre...

  13. Multi-fluid modeling of low-recycling divertor regimes

    International Nuclear Information System (INIS)

    Smirnov, R.D.; Pigarov, A.Yu.; Krasheninnikov, S.I.; Rognlien, T.D.; Soukhanovskii, V.A.; Rensink, M.E.; Maingi, R.; Skinner, C.H.; Stotler, D.P.; Bell, R.E.; Kugel, H.W.

    2010-01-01

    The low-recycling regimes of divertor operation in a single-null NSTX magnetic configuration are studied using computer simulations with the edge plasma transport code UEDGE. The edge plasma transport properties pertinent to the low-recycling regimes are demonstrated. These include the flux-limited character of the parallel heat transport and the high plasma temperatures with the flattened profiles in the scrape-off-layer. It is shown that to maintain the balance of particle fluxes at the core interface the deuterium gas puffing rate should increase as the divertor recycling coefficient decreases. The radial profiles of the heat load to the outer divertor plate, the upstream radial plasma profiles, and the effects of the cross-field plasma transport in the low-recycling regimes are discussed. It is also shown that recycling of lithium impurities evaporating from the divertor plate at high surface temperatures can reverse the low-recycling divertor operational regime to the high-recycling one and may cause thermal instability of the divertor plate (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Multi-Fluid Modeling of Low-Recycling Divertor Regimes

    International Nuclear Information System (INIS)

    Smirnov, R.D.; Pigarov, A.Y.; Krasheninnikov, S.I.; Rognlien, T.D.; Soukhanovskii, V.A.; Rensink, M.E.; Maingi, R.; Skinner, C.H.; Stotler, D.P.; Bell, R.E.; Kugel, H.W.

    2010-01-01

    The low-recycling regimes of divertor operation in a single-null NSTX magnetic configuration are studied using computer simulations with the edge plasma transport code UEDGE. The edge plasma transport properties pertinent to the low-recycling regimes are demonstrated. These include the flux-limited character of the parallel heat transport and the high plasma temperatures with the flattened profiles in the scrape-off-layer. It is shown that to maintain the balance of particle fluxes at the core interface the deuterium gas puffing rate should increase as the divertor recycling coefficient decreases. The radial profiles of the heat load to the outer divertor plate, the upstream radial plasma profiles, and the effects of the cross-field plasma transport in the low-recycling regimes are discussed. It is also shown that recycling of lithium impurities evaporating from the divertor plate at high surface temperatures can reverse the low-recycling divertor operational regime to the high-recycling one and may cause thermal instability of the divertor plate.

  15. Simulating intracrater ash recycling during mid-intensity explosive activity: high temperature laboratory experiments on natural basaltic ash

    Science.gov (United States)

    D'Oriano, Claudia; Pompilio, Massimo; Bertagnini, Antonella; Cioni, Raffaello; Pichavant, Michel

    2010-05-01

    Direct observations of mid-intensity eruptions, in which a huge amount of ash is generated, indicate that ash recycling is quite common. The recognition of juvenile vs. recycled fragments is not straightforward, and no unequivocal, widely accepted criteria exist to support this. The presence of recycled glassy fragments can hide primary magmatic information, introducing bias in the interpretations of the ongoing magmatic and volcanic activity. High temperature experiments were performed at atmospheric pressure on natural samples to investigate the effects of reheating on morphology, texture and composition of volcanic ash. Experiments simulate the transformation of juvenile glassy fragments that, falling into the crater or in the upper part of the conduit, are recycled by following explosions. Textural and compositional modifications obtained in laboratory are compared with similar features observed in natural samples in order to identify some main general criteria to be used for the discrimination of recycled material. Experiments were carried out on tephra produced during Strombolian activity, fire fountains and continuous ash emission at Etna, Stromboli and Vesuvius. Coarse glassy clasts were crushed in a nylon mortar in order to create an artificial ash, and then sieved to select the size interval of 1-0.71 mm. Ash shards were put in a sealed or open quartz tube, in order to prevent or to reproduce effects of air oxidation. The tube was suspended in a HT furnace at INGV-Pisa and kept at different temperatures (up to to 1110°C) for increasing time (0.5-12 hours). Preliminary experiments were also performed under gas flux conditions. Optical and electron microscope observations indicate that high temperature and exposure to the air induce large modifications on clast surface, ranging from change in color, to incipient plastic deformation till complete sintering. Significant change in color of clasts is strictly related to the presence of air, irrespective of

  16. Preliminary evaluation of the immobilization of simulated evaporator concentrate waste in low density polyethylene by extrusion process

    International Nuclear Information System (INIS)

    Cota, Stela; Oliveira, Tania Valeria S. de; Senne Junior, Murillo; Pacheco, Graziella

    2007-01-01

    Simulated evaporator concentrate was prepared by pre-treating sodium borate with calcium hydroxide to produce an insoluble borate salt. The resultant solid waste was blended by extrusion with virgin low density polyethylene (LDPE) in the proportion of 30 wt%. Samples were prepared to evaluate homogeneity, mechanical strength and leaching behavior. The homogeneity of each sample individually and in consecutive samples was indirectly estimated by sectioning each sample in four pieces and submitting each piece to density determination (ASTM standard D-792). Mechanical strength was evaluated through determination of compressive strength (ASTM standard D-695), and the results were compared to the value for the pure polymer and with the limit established by CNEN standard NN-6.09 for cement waste products. Samples were also tested for leaching by accelerated leaching test (ASTM standard C1308). Results showed a good homogeneity. Standard deviations of the density measurements were less than 1% for a single sample and less than 6% considering 3 samples. Polymer compressive strength at yield point and at 5% and 10% strain have increased after the mixture with the simulated waste, indicating an increase on the material strength. Estimated compressive strength was above CNEN standard limit for cement waste products if 5% strain could be considered a reasonable limit to assure structural integrity of the material. Cumulated leaching fraction after 11 days of accelerated leaching test was found to be below 10%, and diffusion coefficient was estimated as 9.06 x 10 -10 cm 2 /s, with deviation of 8.3%. (author)

  17. Preliminary evaluation of the immobilization of simulated evaporator concentrate waste in low density polyethylene by extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Stela; Oliveira, Tania Valeria S. de; Senne Junior, Murillo; Pacheco, Graziella [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: sdsc@cdtn.br

    2007-07-01

    Simulated evaporator concentrate was prepared by pre-treating sodium borate with calcium hydroxide to produce an insoluble borate salt. The resultant solid waste was blended by extrusion with virgin low density polyethylene (LDPE) in the proportion of 30 wt%. Samples were prepared to evaluate homogeneity, mechanical strength and leaching behavior. The homogeneity of each sample individually and in consecutive samples was indirectly estimated by sectioning each sample in four pieces and submitting each piece to density determination (ASTM standard D-792). Mechanical strength was evaluated through determination of compressive strength (ASTM standard D-695), and the results were compared to the value for the pure polymer and with the limit established by CNEN standard NN-6.09 for cement waste products. Samples were also tested for leaching by accelerated leaching test (ASTM standard C1308). Results showed a good homogeneity. Standard deviations of the density measurements were less than 1% for a single sample and less than 6% considering 3 samples. Polymer compressive strength at yield point and at 5% and 10% strain have increased after the mixture with the simulated waste, indicating an increase on the material strength. Estimated compressive strength was above CNEN standard limit for cement waste products if 5% strain could be considered a reasonable limit to assure structural integrity of the material. Cumulated leaching fraction after 11 days of accelerated leaching test was found to be below 10%, and diffusion coefficient was estimated as 9.06 x 10{sup -10} cm{sup 2}/s, with deviation of 8.3%. (author)

  18. Bituminization of simulated PWR type reactor wastes, boric evaporator bottons and ion exchange resins, carried out in CNEN/SP using commercial bitumen available in the Brazilian market

    International Nuclear Information System (INIS)

    Grosche Filho, C.E.; Chandra, U.

    1986-01-01

    The first results of the study of bituminization of simulated PWR wastes, boric evaporator bottons and spent ion-exclange resins (OH - , H + ) and incinerated ash-wates are presented and discussed. The study consisted of characterization of the commercial bitumen, locally available and bitumen wastes products of varying whight compositions. The characterization was carried out using standard analysis methods of ABNT and ASTM, and included measurement of, penetration, softening point and flash point. In addition, the bitumen samples were analized for their resin and asphaltene contents. For leaching studies, wastes products of bitumen and resin loaded with 134 Cs were utilized. The method used was according to the ISO norms. The simulation of the industrial process was carried out using an extruder-evaporator typically used in the plastic industries offered by Industria de Maquinas Miotto Ltda., Sao Bernardo do Campo - SP. (Author) [pt

  19. The GEM code. A simulation program for the evaporation and the fission process of an excited nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Furihata, Shiori [Mitsubishi Research Institute Inc., Tokyo (Japan); Niita, Koji [Research Organization for Information Science and Technology, Tokai, Ibaraki (Japan); Meigo, Shin-ichiro; Ikeda, Yujiro; Maekawa, Fujio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    The GEM code is a simulation program which describes the de-excitation process of an excited nucleus, which is based on the Generalized Evaporation Model and the Atchison fission model. It has been shown that the combination of the Bertini intranuclear cascade model and GEM accurately predicts the cross sections of light fragments, such as Be produced from the proton-induced reactions. It has also been shown that the use of the reevaluated parameters in the Atchison model improves predictions of cross sections of fission fragments produced from the proton-induced reaction on Au. In this report, we present details and the usage of the GEM code. Furthermore, the results of benchmark calculations are shown by using the combination of the Bertini intranuclear cascade model and the GEM code (INC/GEM). Neutron spectra and isotope production cross sections from the reactions on various targets irradiated by protons are calculated with INC/GEM. Those results are compared with experimental data as well as the calculation results with LAHET. INC/GEM reproduces the experiments of double differential neutron emissions from the reaction on Al and Pb. The isotopic distributions for He, Li, and Be produced from the reaction on Ag are in good agreement with experimental data within 50%, although INC/GEM underestimates those of heavier nuclei than O. It is also shown that the predictions with INC/GEM for isotope production of light fragments, such as Li and Be, are better than those calculation with LAHET, particularly for heavy target. INC/GEM also gives better estimates of the cross sections of fission products than LAHET. (author)

  20. Evaporation of liquid droplets of nano- and micro-meter size as a function of molecular mass and intermolecular interactions: experiments and molecular dynamics simulations.

    Science.gov (United States)

    Hołyst, Robert; Litniewski, Marek; Jakubczyk, Daniel

    2017-09-13

    Transport of heat to the surface of a liquid is a limiting step in the evaporation of liquids into an inert gas. Molecular dynamics (MD) simulations of a two component Lennard-Jones (LJ) fluid revealed two modes of energy transport from a vapour to an interface of an evaporating droplet of liquid. Heat is transported according to the equation of temperature diffusion, far from the droplet of radius R. The heat flux, in this region, is proportional to temperature gradient and heat conductivity in the vapour. However at some distance from the interface, Aλ, (where λ is the mean free path in the gas), the temperature has a discontinuity and heat is transported ballistically i.e. by direct individual collisions of gas molecules with the interface. This ballistic transport reduces the heat flux (and consequently the mass flux) by the factor R/(R + Aλ) in comparison to the flux obtained from temperature diffusion. Thus it slows down the evaporation of droplets of sizes R ∼ Aλ and smaller (practically for sizes from 10 3 nm down to 1 nm). We analyzed parameter A as a function of interactions between molecules and their masses. The rescaled parameter, A(k B T b /ε 11 ) 1/2 , is a linear function of the ratio of the molecular mass of the liquid molecules to the molecular mass of the gas molecules, m 1 /m 2 (for a series of chemically similar compounds). Here ε 11 is the interaction parameter between molecules in the liquid (proportional to the enthalpy of evaporation) and T b is the temperature of the gas in the bulk. We tested the predictions of MD simulations in experiments performed on droplets of ethylene glycol, diethylene glycol, triethylene glycol and tetraethylene glycol. They were suspended in an electrodynamic trap and evaporated into dry nitrogen gas. A changes from ∼1 (for ethylene glycol) to approximately 10 (for tetraethylene glycol) and has the same dependence on molecular parameters as obtained for the LJ fluid in MD simulations. The value of x = A

  1. DWPF recycle minimization: Brainstorming session

    International Nuclear Information System (INIS)

    Jacobs, R.A.; Poirier, M.R.

    1993-01-01

    The recycle stream from the DWPF constitutes a major source of water addition to the High Level Waste evaporator system. As now designed, the entire flow of 3.5 to 6.5 gal/min (at sign 25% and 75% attainment, respectively), or 2 gal/min during idling, flow to the 2H evaporator system (Tank 43). Substantial improvement in the HLW water balance and tank volume management is expected if the DWPF recycle to the HLW evaporator system can be significantly reduced. A task team has been appointed to study alternatives for reducing the flow to the HLW evaporator system and make recommendations for implementation and/or further study and evaluation. The brainstorming session detailed in this report was designed to produce the first cut options for the task team to further evaluate

  2. Molecular dynamics simulations to examine structure, energetics, and evaporation/condensation dynamics in small charged clusters of water or methanol containing a single monatomic ion.

    Science.gov (United States)

    Daub, Christopher D; Cann, Natalie M

    2012-11-01

    We study small clusters of water or methanol containing a single Ca(2+), Na(+), or Cl(-) ion with classical molecular dynamics simulations, using models that incorporate polarizability via the Drude oscillator framework. Evaporation and condensation of solvent from these clusters is examined in two systems, (1) for isolated clusters initially prepared at different temperatures and (2) those with a surrounding inert (Ar) gas of varying temperature. We examine these clusters over a range of sizes, from almost bare ions up to 40 solvent molecules. We report data on the evaporation and condensation of solvent from the clusters and argue that the observed temperature dependence of evaporation in the smallest clusters demonstrates that the presence of heated gas alone cannot, in most cases, solely account for bare ion production in electrospray ionization (ESI), neglecting the key contribution of the electric field. We also present our findings on the structure and energetics of the clusters as a function of size. Our data agree well with the abundant literature on hydrated ion clusters and offer some novel insight into the structure of methanol and ion clusters, especially those with a Cl(-) anion, where we observe the presence of chain-like structures of methanol molecules. Finally, we provide some data on the reparameterizations necessary to simulate ions in methanol using the separately developed Drude oscillator models for methanol and for ions in water.

  3. Evaporator bulb

    International Nuclear Information System (INIS)

    Stoll, W.

    1977-01-01

    In order to prevent the hazard of a possible excursion in an evaporator bulb for radioactive liquids there is provided in the bottom of the vessel a recess filled with a neutron-absorbing and moderating material. The bottom drain pipe is coming out sideways and connected with a heated pipe feeding above into the vessel tangentially. (TK) [de

  4. Evaporating firewalls

    Science.gov (United States)

    Van Raamsdonk, Mark

    2014-11-01

    In this note, we begin by presenting an argument suggesting that large AdS black holes dual to typical high-energy pure states of a single holographic CFT must have some structure at the horizon, i.e. a fuzzball/firewall, unless the procedure to probe physics behind the horizon is state-dependent. By weakly coupling the CFT to an auxiliary system, such a black hole can be made to evaporate. In a case where the auxiliary system is a second identical CFT, it is possible (for specific initial states) that the system evolves to precisely the thermofield double state as the original black hole evaporates. In this case, the dual geometry should include the "late-time" part of the eternal AdS black hole spacetime which includes smooth spacetime behind the horizon of the original black hole. Thus, if a firewall is present initially, it evaporates. This provides a specific realization of the recent ideas of Maldacena and Susskind that the existence of smooth spacetime behind the horizon of an evaporating black hole can be enabled by maximal entanglement with a Hawking radiation system (in our case the second CFT) rather than prevented by it. For initial states which are not finely-tuned to produce the thermofield double state, the question of whether a late-time infalling observer experiences a firewall translates to a question about the gravity dual of a typical high-energy state of a two-CFT system.

  5. Hanford recycling

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, I.M.

    1996-09-01

    This paper is a study of the past and present recycling efforts on the Hanford site and options for future improvements in the recycling program. Until 1996, recycling goals were voluntarily set by the waste generators: this year, DOE has imposed goals for all its sites to accomplish by 1999. Hanford is presently meeting the voluntary site goals, but may not be able to meet all the new DOE goals without changes to the program. Most of these new DOE goals are recycling goals: * Reduce the generation of radioactive (low-level) waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of low-level mixed waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of hazardous waste from routine operations 50 percent through source reduction and recycling. * Recycle 33 percent of the sanitary waste from all operations. * Increase affirmative procurement of EPA-designated recycled items to 100 percent. The Hanford recycling program has made great strides-there has been a 98 percent increase in the amount of paper recycled since its inception in 1990. Hanford recycles paper, chemicals cardboard, tires, oil, batteries, rags, lead weights, fluorescent tubes, aerosol products, concrete, office furniture, computer software, drums, toner cartridges, and scrap metal. Many other items are recycled or reused by individual groups on a one time basis without a formal contract. Several contracts are closed-loop contracts which involve all parts of the recycle loop. Considerable savings are generated from recycling, and much more is possible with increased attention and improvements to this program. General methods for improving the recycling program to ensure that the new goals can be met are: a Contract and financial changes 0 Tracking database and methods improvements 0 Expanded recycling efforts. Specifically, the Hanford recycling program would be improved by: 0 Establishing one overall

  6. Liquid evaporation process and evaporator

    International Nuclear Information System (INIS)

    Bergey, Claude; Ravenel, Jacques.

    1975-01-01

    The process described enables a liquid to be evaporated rapidly without any projection. A jet of hot gas is applied to the liquid, the power and angle of the jet being chosen so as to spin the liquid. It is particularly used in the case of radioactive products [fr

  7. Simulation study on the operating characteristics of the heat pipe for combined evaporative cooling of computer room air-conditioning system

    International Nuclear Information System (INIS)

    Han, Zongwei; Zhang, Yanqing; Meng, Xin; Liu, Qiankun; Li, Weiliang; Han, Yu; Zhang, Yanhong

    2016-01-01

    In order to improve the energy efficiency of air conditioning systems in computer rooms, this paper proposed a new concept of integrating evaporative cooling air-conditioning system with heat pipes. Based on a computer room in Shenyang, China, a mathematical model was built to perform transient simulations of the new system. The annual dynamical performance of the new system was then compared with a typical conventional computer room air-conditioning system. The result showed that the new integrated air-conditioning system had better energy efficiency, i.e. 31.31% reduction in energy consumption and 29.49% increase in COP (coefficient of performance), due to the adoption of evaporative condenser and the separate type heat pipe technology. Further study also revealed that the incorporated heat pipes enabled a 36.88% of decrease in the operation duration of the vapor compressor, and a 53.86% of reduction for the activation times of the compressor, which could lead to a longer lifespan of the compressor. The new integrated evaporative cooling air-conditioning system was also tested in different climate regions. It showed that the energy saving of the new system was greatly affected by climate, and it had the best effect in cold and dry regions like Shenyang with up to 31.31% energy saving. In some warm and humid climate regions like Guangzhou, the energy saving could be achieved up to 13.66%. - Highlights: • A novel combined air-conditioning system of computer room is constructed. • The performance of the system and conventional system is simulated and compared. • The applicability of the system in different climate regions is investigated.

  8. Nuclear recycling

    International Nuclear Information System (INIS)

    Spinrad, B.I.

    1985-01-01

    This paper discusses two aspects of the economics of recycling nuclear fuel: the actual costs and savings of the recycling operation in terms of money spent, made, and saved; and the impact of the recycling on the future cost of uranium. The authors review the relevant physical and chemical processes involved in the recycling process. Recovery of uranium and plutonium is discussed. Fuel recycling in LWRs is examined and a table presents the costs of reprocessing and not reprocessing. The subject of plutonium in fast reactors is addressed. Safeguards and weapons proliferation are discussed

  9. Evaporation of Lennard-Jones clusters

    International Nuclear Information System (INIS)

    Roman, C.E.; Garzon, I.L.

    1991-01-01

    Extensive molecular dynamics simulations have been done to study the evaporation of a 13-atom Lennard-Jones cluster. The survival probability and the evaporative lifetime are calculated as a function of the cluster total energy from a classical trajectory analysis. The results are interpreted in terms of the RRK theory of unimolecular dissociation. The calculation of the binding energy of the evaporated species from the evaporation rate and the average kinetic energy release is discussed. (orig.)

  10. The Compressor Recycle System

    OpenAIRE

    Barstad, Bjørn Ove

    2010-01-01

    The compressor recycle system is the main focus of this thesis. When the mass flow through a compressor becomes too low, the compressor can plunge into surge. Surge is a term that is used for axisymmetric oscillation through a compressor and is highly unwanted. The recycle system feeds compressed gas back to the intake when the mass flow becomes too low, and thereby act as a safety system.A mathematical model of the recycle system is extended and simulated in SIMULINK. The mathematical model ...

  11. Literature Review On Impact Of Glycolate On The 2H Evaporator And The Effluent Treatment Facility

    International Nuclear Information System (INIS)

    Adu-Wusu, K.

    2012-01-01

    Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporator serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to reflect the effects from the glycolate additions for the 2H Evaporator system are in order. An evaluation of the 2H Evaporator criticality analysis is also needed. A determination of the amount or fraction of the glycolate in the evaporator overhead is critical to more accurately assess its impact on the ETF. Hence, use of predictive models like OLI Environmental Simulation Package Software (OLI/ESP) and/or testing are recommended for the determination of the glycolate concentration in the overhead. The impact on the ETF depends on the concentration of glycolate in the ETF feed. The impact is classified as minor for feed glycolate concentrations (le) 33 mg/L or 0.44 mM. The ETF unit operations that will have

  12. LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    Adu-Wusu, K.

    2012-05-10

    Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporator serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to reflect the effects from the glycolate additions for the 2H Evaporator system are in order. An evaluation of the 2H Evaporator criticality analysis is also needed. A determination of the amount or fraction of the glycolate in the evaporator overhead is critical to more accurately assess its impact on the ETF. Hence, use of predictive models like OLI Environmental Simulation Package Software (OLI/ESP) and/or testing are recommended for the determination of the glycolate concentration in the overhead. The impact on the ETF depends on the concentration of glycolate in the ETF feed. The impact is classified as minor for feed glycolate concentrations {le} 33 mg/L or 0.44 mM. The ETF unit operations that will have

  13. Unconventional recycling

    Energy Technology Data Exchange (ETDEWEB)

    White, K.M.

    1996-05-01

    Despite advances made in recycling technology and markets for materials over the past few years, recycling at convention centers, particularly on the show floor itself, can be a vexing problem. Part of the problem lies in the fact that recycling at convention centers has more to do with logistics than it does with these industry trends. However, given the varied nature of convention centers, and the shows they book, a rigid approach to recycling at convention centers is not always feasible. Like the numerous different curbside programs serving communities across the country, what works for one convention center--and one show--many not work for another. These difficulties notwithstanding, more convention centers are offering recycling programs today, and more groups booking conventions these days have begun requesting recycling services.

  14. Streamer Evaporation

    Science.gov (United States)

    Suess, Steven T.; Wang, A. H.; Wu, Shi T.; Nerney, S.

    1998-01-01

    Evaporation is the consequence of slow plasma heating near the tops of streamers where the plasma is only weakly contained by the magnetic field. The form it takes is the slow opening of field lines at the top of the streamer and transient formation of new solar wind. It was discovered in polytropic model calculations, where due to the absence of other energy loss mechanisms in magnetostatic streamers, its ultimate endpoint is the complete evaporation of the streamer. This takes, for plausible heating rates, weeks to months in these models. Of course streamers do not behave this way, for more than one reason. One is that there are losses due to thermal conduction to the base of the streamer and radiation from the transition region. Another is that streamer heating must have a characteristic time constant and depend on the ambient physical conditions. We use our global Magnetohydrodynamics (MHD) model with thermal conduction to examine a few examples of the effect of changing the heating scale height and of making ad hoc choices for how the heating depends on ambient conditions. At the same time, we apply and extend the analytic model of streamers, which showed that streamers will be unable to contain plasma for temperatures near the cusp greater than about 2xl0(exp 6) K. Slow solar wind is observed to come from streamers through transient releases. A scenario for this that is consistent with the above physical process is that heating increases the near-cusp temperature until field lines there are forced open. The subsequent evacuation of the flux tubes by the newly forming slow wind decreases the temperature and heating until the flux tubes are able to reclose. Then, over a longer time scale, heating begins to again refill the flux tubes with plasma and increase the temperature until the cycle repeats itself. The calculations we report here are first steps towards quantitative evaluation of this scenario.

  15. Revealing Invisible Water: Moisture Recycling as an Ecosystem Service.

    Science.gov (United States)

    Keys, Patrick W; Wang-Erlandsson, Lan; Gordon, Line J

    2016-01-01

    An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized

  16. Thermogravimetric analysis of fuel film evaporation

    Institute of Scientific and Technical Information of China (English)

    HU Zongjie; LI Liguang; YU Shui

    2006-01-01

    Thermogravimetric analysis (TGA) was compared with the petrochemical distillation measurement method to better understand the characteristics of fuel film evaporation at different wall tem- peratures. The film evaporation characteristics of 90# gasoline, 93# gasoline and 0# diesel with different initial thicknesses were investigated at different environmental fluxes and heating rates. The influences of heating rate, film thickness and environmental flux on fuel film evaporation for these fuels were found. The results showed that the environmental conditions in TGA were similar to those for fuel films in the internal combustion engines, so data from TGA were suitable for the analysis of fuel film evaporation. TGA could simulate the key influencing factors for fuel film evaporation and could investigate the basic quantificational effect of heating rate and film thickness. To get a rapid and sufficient fuel film evaporation, sufficiently high wall temperature is necessary. Evaporation time decreases at a high heating rate and thin film thickness, and intense gas flow is important to promoting fuel film evaporation. Data from TGA at a heating rate of 100℃/min are fit to analyze the diesel film evaporation during cold-start and warming-up. Due to the tense molecular interactions, the evaporation sequence could not be strictly divided according to the boiling points of each component for multicomponent dissolved mixture during the quick evaporation process, and the heavier components could vaporize before reaching their boiling points. The 0# diesel film would fully evaporate when the wall temperature is beyond 250℃.

  17. Advanced evaporator technology progress report FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    Chamberlain, D.; Hutter, J.C.; Leonard, R.A. [and others

    1995-01-01

    This report summarizes the work that was completed in FY 1992 on the program {open_quotes}Technology Development for Concentrating Process Streams.{close_quotes} The purpose of this program is to evaluate and develop evaporator technology for concentrating radioactive waste and product streams such as those generated by the TRUEX process. Concentrating these streams and minimizing the volume of waste generated can significantly reduce disposal costs; however, equipment to concentrate the streams and recycle the decontaminated condensates must be installed. LICON, Inc., is developing an evaporator that shows a great deal of potential for this application. In this report, concepts that need to be incorporated into the design of an evaporator operated in a radioactive environment are discussed. These concepts include criticality safety, remote operation and maintenance, and materials of construction. Both solubility and vapor-liquid equilibrium data are needed to design an effective process for concentrating process streams. Therefore, literature surveys were completed and are summarized in this report. A model that is being developed to predict vapor phase compositions is described. A laboratory-scale evaporator was purchased and installed to study the evaporation process and to collect additional data. This unit is described in detail. Two new LICON evaporators are being designed for installation at Argonne-East in FY 1993 to process low-level radioactive waste generated throughout the laboratory. They will also provide operating data from a full-sized evaporator processing radioactive solutions. Details on these evaporators are included in this report.

  18. Advanced evaporator technology progress report FY 1992

    International Nuclear Information System (INIS)

    Chamberlain, D.; Hutter, J.C.; Leonard, R.A.

    1995-01-01

    This report summarizes the work that was completed in FY 1992 on the program open-quotes Technology Development for Concentrating Process Streams.close quotes The purpose of this program is to evaluate and develop evaporator technology for concentrating radioactive waste and product streams such as those generated by the TRUEX process. Concentrating these streams and minimizing the volume of waste generated can significantly reduce disposal costs; however, equipment to concentrate the streams and recycle the decontaminated condensates must be installed. LICON, Inc., is developing an evaporator that shows a great deal of potential for this application. In this report, concepts that need to be incorporated into the design of an evaporator operated in a radioactive environment are discussed. These concepts include criticality safety, remote operation and maintenance, and materials of construction. Both solubility and vapor-liquid equilibrium data are needed to design an effective process for concentrating process streams. Therefore, literature surveys were completed and are summarized in this report. A model that is being developed to predict vapor phase compositions is described. A laboratory-scale evaporator was purchased and installed to study the evaporation process and to collect additional data. This unit is described in detail. Two new LICON evaporators are being designed for installation at Argonne-East in FY 1993 to process low-level radioactive waste generated throughout the laboratory. They will also provide operating data from a full-sized evaporator processing radioactive solutions. Details on these evaporators are included in this report

  19. Determination of paraffins in food simulants and packaging materials by liquid chromatography with evaporative mass detection and identification of paraffin type by liquid chromatography/gas chromatography and fourier transform infrared spectroscopy

    NARCIS (Netherlands)

    Simal-Gándara, J.; Sarria-Vidal, M.; Rijk, M.A.H.

    2000-01-01

    A liquid chromatographic method with evaporative mass detection (EMD) is described for the determination of paraffins in food contact materials that do not contain polyolefin oligomers, or paraffins migrating from these materials into fatty food simulants or certain simple foods. A normal-phase

  20. Simulation Analysis of the Four Configurations of Solar Desiccant Cooling System Using Evaporative Cooling in Tropical Weather in Malaysia

    Directory of Open Access Journals (Sweden)

    M. M. S. Dezfouli

    2014-01-01

    Full Text Available A high demand for air conditioning systems exists in hot and humid regions because of the warm climate during the year. The high energy consumption of conventional air conditioning system is the reason for our investigation of the solar desiccant cooling system as an energy-efficient cooling system. Four model configurations were considered to determine the best configuration of a solar desiccant cooling system: one-stage ventilation, one-stage recirculation, two-stage ventilation, and two-stage recirculation. These models were stimulated for 8,760 hr of operation under hot and humid weather in Malaysia. Several parameters (i.e., coefficient of performance or COP, room temperature and humidity ratio, and the solar fraction of each system were evaluated by detecting the temperature and humidity ratio of the different points of each configuration by TRNSYS simulation. The latent and sensible loads of the test room were 0.875 kW and 2.625 kW, respectively. By investigating the simulation results of the four systems, the ventilation modes were found to be higher than the recirculation modes in the one- and two-stage solar desiccant cooling systems. The isothermal dehumidification COP of the two-stage ventilation was higher than that of the two-stage recirculation. Hence, the two-stage ventilation mode desiccant cooling system in a hot and humid area has higher efficiency than the other configurations.

  1. Mixed phase evaporation source

    International Nuclear Information System (INIS)

    1975-01-01

    Apparatus for reducing convection current heat loss in electron beam evaporator is described. A material to be evaporated (evaporant) is placed in the crucible of an electron beam evaporation source along with a porous mass formed of a powdered or finely divided solid to act as an impedance to convection currents. A feed system is employed to replenish the supply of evaporant as it is vaporized

  2. Continuous processing of recombinant proteins: Integration of inclusion body solubilization and refolding using simulated moving bed size exclusion chromatography with buffer recycling.

    Science.gov (United States)

    Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

    2013-12-06

    An integrated process which combines continuous inclusion body dissolution with NaOH and continuous matrix-assisted refolding based on closed-loop simulated moving bed size exclusion chromatography was designed and experimentally evaluated at laboratory scale. Inclusion bodies from N(pro) fusion pep6His and N(pro) fusion MCP1 from high cell density fermentation were continuously dissolved with NaOH, filtered and mixed with concentrated refolding buffer prior to refolding by size exclusion chromatography (SEC). This process enabled an isocratic operation of the simulated moving bed (SMB) system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling by concentrating the raffinate using tangential flow filtration. With this continuous refolding process, we increased the refolding and cleavage yield of both model proteins by 10% compared to batch dilution refolding. Furthermore, more than 99% of the refolding buffer of the raffinate could be recycled which reduced the buffer consumption significantly. Based on the actual refolding data, we compared throughput, productivity, and buffer consumption between two batch dilution refolding processes - one using urea for IB dissolution, the other one using NaOH for IB dissolution - and our continuous refolding process. The higher complexity of the continuous refolding process was rewarded with higher throughput and productivity as well as significantly lower buffer consumption compared to the batch dilution refolding processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Length and time scales of atmospheric moisture recycling

    NARCIS (Netherlands)

    Van der Ent, R.J.; Savenije, H.H.G.

    2011-01-01

    It is difficult to quantify the degree to which terrestrial evaporation supports the occurrence of precipitation within a certain study region (i.e. regional moisture recycling) due to the scale- and shape-dependence of regional moisture recycling ratios. In this paper we present a novel approach to

  4. Tire Recycling

    Science.gov (United States)

    1997-01-01

    Cryopolymers, Inc. tapped NASA expertise to improve a process for recycling vehicle tires by converting shredded rubber into products that can be used in asphalt road beds, new tires, hoses, and other products. In conjunction with the Southern Technology Applications Center and Stennis Space Center, NASA expertise in cryogenic fuel-handling needed for launch vehicle and spacecraft operations was called upon to improve the recycling concept. Stennis advised Cryopolymers on the type of equipment required, as well as steps to reduce the amount of liquid nitrogen used in the process. They also guided the company to use more efficient ways to control system hardware. It is estimated that more than 300 million tires nationwide are produced per year. Cryopolymers expects to reach a production rate of 5,000 tires recycled per day.

  5. New models for droplet heating and evaporation

    KAUST Repository

    Sazhin, Sergei S.

    2013-02-01

    A brief summary of new models for droplet heating and evaporation, developed mainly at the Sir Harry Ricardo Laboratory of the University of Brighton during 2011-2012, is presented. These are hydrodynamic models for mono-component droplet heating and evaporation, taking into account the effects of the moving boundary due to evaporation, hydrodynamic models of multi-component droplet heating and evaporation, taking and not taking into account the effects of the moving boundary, new kinetic models of mono-component droplet heating and evaporation, and a model for mono-component droplet evaporation, based on molecular dynamics simulation. The results, predicted by the new models are compared with experimental data and the prehctions of the previously developed models where possible. © 2013 Asian Network for Scientific Information.

  6. Is evaporative colling important for shallow clouds?

    Science.gov (United States)

    Gentine, P.; Park, S. B.; Davini, P.; D'Andrea, F.

    2017-12-01

    We here investigate and test using large-eddy simulations the hypothesis that evaporative cooling might not be crucial for shallow clouds. Results from various Shallow convection and stratocumulus LES experiments show that the influence of evaporative cooling is secondary compared to turbulent mixing, which dominates the buoyancy reversal. In shallow cumulus subising shells are not due to evaporative cooling but rather reflect a vortical structure, with a postive buoyancy anomaly in the core due to condensation. Disabling evaporative cooling has negligible impact on this vortical structure and on buoyancy reversal. Similarly in non-precipitating stratocumuli evaporative cooling is negeligible copmared to other factors, especially turbulent mixing and pressure effects. These results emphasize that it may not be critical to icnlude evaporative cooling in parameterizations of shallow clouds and that it does not alter entrainment.

  7. Continuous processing of recombinant proteins: integration of refolding and purification using simulated moving bed size-exclusion chromatography with buffer recycling.

    Science.gov (United States)

    Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

    2014-04-11

    Continuous processing of recombinant proteins was accomplished by combining continuous matrix-assisted refolding and purification by tandem simulated moving bed (SMB) size-exclusion chromatography (SEC). Recombinant proteins, N(pro) fusion proteins from inclusion bodies were dissolved with NaOH and refolded in the SMB system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling of the refolding buffer of the raffinate by tangential flow filtration. For further purification of the refolded proteins, a second SMB operation also based on SEC was added. The whole system could be operated isocratically with refolding buffer as the desorbent buffer, and buffer recycling could also be applied in the purification step. Thus, a significant reduction in buffer consumption was achieved. The system was evaluated with two proteins, the N(pro) fusion pep6His and N(pro) fusion MCP-1. Refolding solution, which contained residual N(pro) fusion peptide, the cleaved autoprotease N(pro), and the cleaved target peptide was used as feed solution. Full separation of the cleaved target peptide from residual proteins was achieved at a purity and recovery in the raffinate and extract, respectively, of approximately 100%. In addition, more than 99% of the refolding buffer of the raffinate was recycled. A comparison of throughput, productivity, and buffer consumption of the integrated continuous process with two batch processes demonstrated that up to 60-fold higher throughput, up to 180-fold higher productivity, and at least 28-fold lower buffer consumption can be obtained by the integrated continuous process, which compensates for the higher complexity. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Understanding Atom Probe Tomography of Oxide-Supported Metal Nanoparticles by Correlation with Atomic-Resolution Electron Microscopy and Field Evaporation Simulation.

    Science.gov (United States)

    Devaraj, Arun; Colby, Robert; Vurpillot, François; Thevuthasan, Suntharampillai

    2014-04-17

    Oxide-supported metal nanoparticles are widely used in heterogeneous catalysis. The increasingly detailed design of such catalysts necessitates three-dimensional characterization with high spatial resolution and elemental selectivity. Laser-assisted atom probe tomography (APT) is uniquely suited to the task but faces challenges with the evaporation of metal/insulator systems. Correlation of APT with aberration-corrected scanning transmission electron microscopy (STEM), for Au nanoparticles embedded in MgO, reveals preferential evaporation of the MgO and an inaccurate assessment of nanoparticle composition. Finite element field evaporation modeling is used to illustrate the evolution of the evaporation front. Nanoparticle composition is most accurately predicted when the MgO is treated as having a locally variable evaporation field, indicating the importance of considering laser-oxide interactions and the evaporation of various molecular oxide ions. These results demonstrate the viability of APT for analysis of oxide-supported metal nanoparticles, highlighting the need for developing a theoretical framework for the evaporation of heterogeneous materials.

  9. Evaporator Cleaning Studies

    International Nuclear Information System (INIS)

    Wilmarth, W.R.

    1999-01-01

    Operation of the 242-16H High Level Waste Evaporator proves crucial to liquid waste management in the H-Area Tank Farm. Recent operational history of the Evaporator showed significant solid formation in secondary lines and in the evaporator pot. Additional samples remain necessary to ensure material identity in the evaporator pot. Analysis of these future samples will provide actinide partitioning information and dissolution characteristics of the solid material from the pot to ensure safe chemical cleaning

  10. Simulation and design of distillation units for treatment of sulfite pulping condensates to recover methanol and furfural. Part I. Incorporation with an evaporation unit and use of secondary steam

    Energy Technology Data Exchange (ETDEWEB)

    Zacchi, G.; Aly, G.

    1979-06-01

    A distillation unit was simulated using DESTLA, a computer program for steady-state calculations of general multicomponent distillation units. Vapor-liquid and liquid-liquid equilibria were both computed by EQUIL, a computer program for computation and plotting of such equilibria. The simulations resulted in a distillation unit consisting of three columns. Energy consumed in the first column dominates the operating costs of the unit. The first of the three different alternatives studied for satisfying the energy requirements of the first column is presented. Incorporating the first column into an evaporation unit yields low steam consumption. However, a decrease in evaporation capacity due to the temperature drop in the first column and complex control design are the disadvantages associated with this alternative.

  11. Evaporation and Climate Change

    NARCIS (Netherlands)

    Brandsma, T.

    1993-01-01

    In this article the influence of climate change on evaporation is discussed. The emphasis is on open water evaporation. Three methods for calculating evaporation are compared considering only changes in temperature and factors directly dependent on temperature. The Penman-method is used to

  12. The recycling of domestic waste water. A study of the factors influencing the storage capacity and the simulation of the usage patterns

    Energy Technology Data Exchange (ETDEWEB)

    Fewkes, A; Ferris, S A

    1982-01-01

    The flushing of toilets with recycled domestic waste water makes a significant saving in the use of potable water. The size of the storage tank is a critical factor in the design of such a system; the inputs to the storage, which are random, are influenced by the size of family and individual washing and bathing habits. The demand from the storage tank is random in time but the volume is constant at each occurrence. A method of generating these waste water time series, with their inherent stochastic nature, is described. These simulated event patterns are then used to investigate the operation of a single-tank waste water storage system. The computer model determines the percentage of water conserved for several combinations of storage capacity and family size: the effect of changes in design parameters and operating conditions on the system performance is also assessed.

  13. Chlorine condenser-evaporator simulation

    Science.gov (United States)

    Muraveva, E. A.

    2017-10-01

    Refrigeration machines are an integral part of chemical engineering. Coldness in mechanical engineering is used to improve the properties of steels, to stabilize the shape and size of steel parts, to restore the dimensions of worn steel hardened parts, to fasten the parts to be machined during cutting and grinding, to ensure fixed planting during assembly, bending pipelines, deep drawing and stamping parts from sheet materials, in the manufacture and processing of rubber parts, with solid anodizing of aluminum alloy parts.

  14. Biofouling potential and material reactivity in a simulated water distribution network supplied with stormwater recycled via managed aquifer recharge.

    Science.gov (United States)

    Gonzalez, Dennis; Tjandraatmadja, Grace; Barry, Karen; Vanderzalm, Joanne; Kaksonen, Anna H; Dillon, Peter; Puzon, Geoff J; Sidhu, Jatinder; Wylie, Jason; Goodman, Nigel; Low, Jason

    2016-11-15

    The injection of stormwater into aquifers for storage and recovery during high water demand periods is a promising technology for augmenting conventional water reserves. Limited information exists regarding the potential impact of aquifer treated stormwater in distribution system infrastructure. This study describes a one year pilot distribution pipe network trial to determine the biofouling potential for cement, copper and polyvinyl chloride pipe materials exposed to stormwater stored in a limestone aquifer compared to an identical drinking water rig. Median alkalinity (123 mg/L) and colour (12 HU) in stormwater was significantly higher than in drinking water (82 mg/L and 1 HU) and pipe discolouration was more evident for stormwater samples. X-ray Diffraction and Fluorescence analyses confirmed this was driven by the presence of iron rich amorphous compounds in more thickly deposited sediments also consistent with significantly higher median levels of iron (∼0.56 mg/L) in stormwater compared to drinking water (∼0.17 mg/L). Water type did not influence biofilm development as determined by microbial density but faecal indicators were significantly higher for polyvinyl chloride and cement exposed to stormwater. Treatment to remove iron through aeration and filtration would reduce the potential for sediment accumulation. Operational and verification monitoring parameters to manage scaling, corrosion, colour, turbidity and microbial growth in recycled stormwater distribution networks are discussed. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  15. Recycle and reduction of waste water in ISL operation

    International Nuclear Information System (INIS)

    Du Zhiming; Liu Naizhong; Su Xuebin; Li Jianhua; Zou Maoqing; Xing Yongguo

    2014-01-01

    Sandstone type uranium resources will be promote the main force of natural uranium production in China. The wastewater produced in the process of in-situ leaching mining need to be studied specially, so as to meet the requirements of green mining and realize the recycling of wastewater and decrement. We have researched and adopted including nature groundwater environmental recycling, liquor of precipitation recycling, optimization of elution process, the transformation waste water reduction, water evaporation reduction and a series of technological measures. The field application results show that the wastewater recycling and reduction in the process of production achieved a good environmental protection effect. (authors)

  16. Recycling Lesson Plan

    Science.gov (United States)

    Okaz, Abeer Ali

    2013-01-01

    This lesson plan designed for grade 2 students has the goal of teaching students about the environmental practice of recycling. Children will learn language words related to recycling such as: "we can recycle"/"we can't recycle" and how to avoid littering with such words as: "recycle paper" and/or "don't throw…

  17. Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle

    International Nuclear Information System (INIS)

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.

    2013-01-01

    of the decontaminated Recycle stream may be suitable for the Effluent Treatment Facility, where it could be evaporated and solidified. The contaminated slurry stream containing the absorbents and radionuclides will be preliminarily characterized in this phase of the program to evaluate disposal options, and disposition routes will be tested in the next phase. The testing described herein will aid in selection of the best disposal pathway. Several research tasks have been identified that are needed for this initial phase: Simulant formulation- Concentration of Recycle to reduce storage volume; Blending of concentrated Recycle with tank waste; Sorption of radionuclides; and, Precipitation of radionuclides. After this initial phase of testing, additional tasks are expected to be identified for development. These tasks likely include evaluation and testing of applicable solid-liquid separation technologies, slurry rheology measurements, composition variability testing and evaluations, corrosion and erosion testing, slurry storage and immobilization investigations, and decontaminated Recycle evaporation and solidification. Although there are a number of unknown parameters listed in the technical details of the concepts described here, many of these parameters have precedence and do not generally require fundamental new scientific breakthroughs. Many of the materials and processes described are already used in radioactive applications in the DOE complex, or have been tested previously in comparable conditions. Some of these materials and equipment are already used in High Level Waste applications, which are much more complex and aggressive conditions than the LAW Recycle stream. In some cases, the unknown parameters are simply extensions of already studied conditions, such as tank waste corrosion chemistry. The list of testing needs at first appears daunting, but virtually all have been done before, although there are potential issues with compatibility with this unique

  18. Evaporation rate of nucleating clusters.

    Science.gov (United States)

    Zapadinsky, Evgeni

    2011-11-21

    The Becker-Döring kinetic scheme is the most frequently used approach to vapor liquid nucleation. In the present study it has been extended so that master equations for all cluster configurations are included into consideration. In the Becker-Döring kinetic scheme the nucleation rate is calculated through comparison of the balanced steady state and unbalanced steady state solutions of the set of kinetic equations. It is usually assumed that the balanced steady state produces equilibrium cluster distribution, and the evaporation rates are identical in the balanced and unbalanced steady state cases. In the present study we have shown that the evaporation rates are not identical in the equilibrium and unbalanced steady state cases. The evaporation rate depends on the number of clusters at the limit of the cluster definition. We have shown that the ratio of the number of n-clusters at the limit of the cluster definition to the total number of n-clusters is different in equilibrium and unbalanced steady state cases. This causes difference in evaporation rates for these cases and results in a correction factor to the nucleation rate. According to rough estimation it is 10(-1) by the order of magnitude and can be lower if carrier gas effectively equilibrates the clusters. The developed approach allows one to refine the correction factor with Monte Carlo and molecular dynamic simulations.

  19. Recycling production designs: the value of coordination and flexibility in aluminum recycling operations

    Science.gov (United States)

    Brommer, Tracey H.

    The growing motivation for aluminum recycling has prompted interest in recycling alternative and more challenging secondary materials. The nature of these alternative secondary materials necessitates the development of an intermediate recycling facility that can reprocess the secondary materials into a liquid product Two downstream aluminum remelters will incorporate the liquid products into their aluminum alloy production schedules. Energy and environmental benefits result from delivering the products as liquid but coordination challenges persist because of the energy cost to maintain the liquid. Further coordination challenges result from the necessity to establish a long term recycling production plan in the presence of long term downstream aluminum remelter production uncertainty and inherent variation in the daily order schedule of the downstream aluminum remelters. In this context a fundamental question arises, considering the metallurgical complexities of dross reprocessing, what is the value of operating a coordinated set of by-product reprocessing plants and remelting cast houses? A methodology is presented to calculate the optimal recycling center production parameters including 1) the number of recycled products, 2) the volume of recycled products, 3) allocation of recycled materials across recycled products, 4) allocation of recycled products across finished alloys, 4) the level of flexibility for the recycling center to operate. The methods implemented include, 1) an optimization model to describe the long term operations of the recycling center, 2) an uncertainty simulation tool, 3) a simulation optimization method, 4) a dynamic simulation tool with four embedded daily production optimization models of varying degrees of flexibility. This methodology is used to quantify the performance of several recycling center production designs of varying levels of coordination and flexibility. This analysis allowed the identification of the optimal recycling

  20. Water evaporation: a transition path sampling study.

    Science.gov (United States)

    Varilly, Patrick; Chandler, David

    2013-02-07

    We use transition path sampling to study evaporation in the SPC/E model of liquid water. On the basis of thousands of evaporation trajectories, we characterize the members of the transition state ensemble (TSE), which exhibit a liquid-vapor interface with predominantly negative mean curvature at the site of evaporation. We also find that after evaporation is complete, the distributions of translational and angular momenta of the evaporated water are Maxwellian with a temperature equal to that of the liquid. To characterize the evaporation trajectories in their entirety, we find that it suffices to project them onto just two coordinates: the distance of the evaporating molecule to the instantaneous liquid-vapor interface and the velocity of the water along the average interface normal. In this projected space, we find that the TSE is well-captured by a simple model of ballistic escape from a deep potential well, with no additional barrier to evaporation beyond the cohesive strength of the liquid. Equivalently, they are consistent with a near-unity probability for a water molecule impinging upon a liquid droplet to condense. These results agree with previous simulations and with some, but not all, recent experiments.

  1. Optimizing the operating parameters of corona electrostatic separation for recycling waste scraped printed circuit boards by computer simulation of electric field.

    Science.gov (United States)

    Li, Jia; Lu, Hongzhou; Liu, Shushu; Xu, Zhenming

    2008-05-01

    The printed circuit board (PCB) has a metal content of nearly 28% metal, including an abundance of nonferrous metals such as copper, lead, and tin. The purity of precious metals in PCBs is more than 10 times that of rich-content minerals. Therefore, the recycling of PCBs is an important subject, not only from the viewpoint of waste treatment, but also with respect to the recovery of valuable materials. Compared with traditional process the corona electrostatic separation (CES) had no waste water or gas during the process and it had high productivity with a low-energy cost. In this paper, the roll-type corona electrostatic separator was used to separate metals and nonmetals from scraped waste PCBs. The software MATLAB was used to simulate the distribution of electric field in separating space. It was found that, the variations of parameters of electrodes and applied voltages directly influenced the distribution of electric field. Through the correlation of simulated and experimental results, the good separation results were got under the optimized operating parameter: U=20-30 kV, L=L(1)=L(2)=0.21 m, R(1)=0.114, R(2)=0.019 m, theta(1)=20 degrees and theta(2)=60 degrees .

  2. Recycling waste

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P I.S.

    1976-01-01

    It is being realized that if environmental quality is to be improved the amount of waste generated by man has to be substantially reduced. There are two ways this can be achieved. First, by conserving materials and energy, and sacrificing economic growth, a solution that is completely unacceptable because it would mean some form of rationing, mass unemployment, and collapse of society as it is known. The second way to reduce the volume of waste is by planned recycling, re-use, and recovery. Already the reclamation industry recovers, processes, and turns back for re-use many products used by industry and thereby reduces the UK's import bill for raw materials. In the book, the author sets out the various ways materials may be recovered from industrial and municipal wastes. The broad technology of waste management is covered and attention is focused on man's new resources lying buried in the mountains of industrial wastes, the emissions from stocks, the effluents and sludges that turn rivers into open sewers, and municipal dumps in seventeen chapters. The final chapter lists terms and concepts used in waste technology, organizations concerned with waste management, and sources of information about recycling waste. (MCW)

  3. Microwave heating type evaporator

    International Nuclear Information System (INIS)

    Taura, Masazumi; Nishi, Akio; Morimoto, Takashi; Izumi, Jun; Tamura, Kazuo; Morooka, Akihiko.

    1987-01-01

    Purpose: To prevent evaporization stills against corrosion due to radioactive liquid wastes. Constitution: Microwaves are supplied from a microwave generator by way of a wave guide tube and through a microwave permeation window to the inside of an evaporatization still. A matching device is attached to the wave guide tube for transmitting the microwaves in order to match the impedance. When the microwaves are supplied to the inside of the evaporization still, radioactive liquid wastes supplied from a liquid feed port by way of a spray tower to the inside of the evaporization still is heated and evaporated by the induction heating of the microwaves. (Seki, T.)

  4. Semiclassical Approach to Black Hole Evaporation

    OpenAIRE

    Lowe, David A.

    1992-01-01

    Black hole evaporation may lead to massive or massless remnants, or naked singularities. This paper investigates this process in the context of two quite different two dimensional black hole models. The first is the original CGHS model, the second is another two dimensional dilaton-gravity model, but with properties much closer to physics in the real, four dimensional, world. Numerical simulations are performed of the formation and subsequent evaporation of black holes and the results are fou...

  5. Recycling Facilities - Land Recycling Cleanup Locations

    Data.gov (United States)

    NSGIC Education | GIS Inventory — Land Recycling Cleanup Location Land Recycling Cleanup Locations (LRCL) are divided into one or more sub-facilities categorized as media: Air, Contained Release or...

  6. Evaporation, Boiling and Bubbles

    Science.gov (United States)

    Goodwin, Alan

    2012-01-01

    Evaporation and boiling are both terms applied to the change of a liquid to the vapour/gaseous state. This article argues that it is the formation of bubbles of vapour within the liquid that most clearly differentiates boiling from evaporation although only a minority of chemistry textbooks seems to mention bubble formation in this context. The…

  7. Rapid Evaporation of microbubbles

    Science.gov (United States)

    Gautam, Jitendra; Esmaeeli, Asghar

    2008-11-01

    When a liquid is heated to a temperature far above its boiling point, it evaporates abruptly. Boiling of liquid at high temperatures can be explosive and destructive, and poses a potential hazard for a host of industrial processes. Explosive boiling may occur if a cold and volatile liquid is brought into contact with a hot and non-volatile liquid, or if a liquid is superheated or depressurized rapidly. Such possibilities are realized, for example, in the depressurization of low boiling point liquefied natural gas (LNG) in the pipelines or storage tanks as a result of a leak. While boiling of highly heated liquids can be destructive at macroscale, the (nearly) instantaneous pace of the process and the release of large amount of kinetic energy make the phenomena extremely attractive at microscale where it is possible to utilize the released energy to derive micromechanical systems. For instance, there is currently a growing interest in micro-explosion of liquid for generation of micro bubbles for actuation purposes. The aim of the current study is to gain a fundamental understanding of the subject using direct numerical simulations. In particular, we seek to investigate the boundary between stable and unstable nucleus growth in terms of the degree of liquid superheat and to compare the dynamics of unstable and stable growth.

  8. Installation of a three-dimensional simulation method for core-physical description of pebble bed reactors with multiple recycling process at the example of the AVR

    International Nuclear Information System (INIS)

    Grotkamp, T.

    1984-01-01

    To describe the core-physical behaviour of pebble bed reactors simulation models are used, which reproduce the burn-up/recycling and - resulting - calculate criticality and neutron spectrum as well as neutron flux and temperature distribution. Modelling the AVR-reactor requires a three-dimensional treating for detailed considerations because of the graphite noses extending into the core. Such a system is built up in the present work and compared with the results of the two-dimensional model standardizated from operational side. The agreement is so good that the latter one is sufficient for the calculations accompanying the operation. The comparison with results of measurement is very satisfying in regard to fuel element distribution and temperature coefficient. As in all theoretical investigations there stays a discrepance of a little more than 1 nile against the measurement at the reactivity equivalence of the AVR rod-bank. On the other hand it is possible to reproduce the rod-bank curve resulting of the calibration very exactly with the present model. (orig.) [de

  9. Trends in evaporation of a large subtropical lake

    Science.gov (United States)

    Hu, Cheng; Wang, Yongwei; Wang, Wei; Liu, Shoudong; Piao, Meihua; Xiao, Wei; Lee, Xuhui

    2017-07-01

    How rising temperature and changing solar radiation affect evaporation of natural water bodies remains poor understood. In this study, evaporation from Lake Taihu, a large (area 2400 km2) freshwater lake in the Yangtze River Delta, China, was simulated by the CLM4-LISSS offline lake model and estimated with pan evaporation data. Both methods were calibrated against lake evaporation measured directly with eddy covariance in 2012. Results show a significant increasing trend of annual lake evaporation from 1979 to 2013, at a rate of 29.6 mm decade-1 according to the lake model and 25.4 mm decade-1 according to the pan method. The mean annual evaporation during this period shows good agreement between these two methods (977 mm according to the model and 1007 mm according to the pan method). A stepwise linear regression reveals that downward shortwave radiation was the most significant contributor to the modeled evaporation trend, while air temperature was the most significant contributor to the pan evaporation trend. Wind speed had little impact on the modeled lake evaporation but had a negative contribution to the pan evaporation trend offsetting some of the temperature effect. Reference evaporation was not a good proxy for the lake evaporation because it was on average 20.6 % too high and its increasing trend was too large (56.5 mm decade-1).

  10. Out-of-tank evaporator demonstration: Tanks focus area

    International Nuclear Information System (INIS)

    1998-11-01

    Approximately 100 million gal of liquid waste is stored in underground storage tanks (UST)s at the Hanford Site, Idaho National Engineering and Environmental Laboratory (INEEL), Savannah River Site (SRS), and Oak Ridge Reservation (ORR). This waste is radioactive with a high salt content. The US Department of Energy (DOE) wants to minimize the volume of radioactive liquid waste in USTs by removing the excess water. This procedure conserves tank space; lowers the cost of storage; and reduces the volume of wastes subsequently requiring separation, immobilization, and disposal. The Out-of-Tank Evaporator Demonstration (OTED) was initiated to test a modular, skid-mounted evaporator. A mobile evaporator system manufactured by Delta Thermal Inc. was selected. The evaporator design was routinely used in commercial applications such as concentrating metal-plating wastes for recycle and concentrating ethylene glycol solutions. In FY 1995, the skid-mounted evaporator system was procured and installed in an existing ORNL facility (Building 7877) with temporary shielding and remote controls. The evaporator system was operational in January 1996. The system operated 24 h/day and processed 22,000 gal of Melton Valley Storage Tank (MVST) supernatant. The distillate contained essentially no salts or radionuclides. Upon completion of the demonstration, the evaporator underwent decontamination testing to illustrate the feasibility of hands-on maintenance and potential transport to another DOE facility. This report describes the process and the evaporator, its performance at ORNL, future plans, applications of this technology, cost estimates, regulatory and policy considerations, and lessons learned

  11. Recycling of electronic scrap

    DEFF Research Database (Denmark)

    Legarth, Jens Brøbech

    This Ph.D. thesis deals with the growingly important field of electronics recycling with special attention to the problem of printed circuit board recycling. A literature survey of contemporary electronics recycling and printed circuit board recycling is presented.Further, an analysis of the role...

  12. Green Science: Revisiting Recycling

    Science.gov (United States)

    Palliser, Janna

    2011-01-01

    Recycling has been around for a long time--people have reused materials and refashioned them into needed items for thousands of years. More recently, war efforts encouraged conservation and reuse of materials, and in the 1970s recycling got its official start when recycling centers were created. Now, curbside recycling programs and recycling…

  13. Vacuum evaporation of pure metals

    OpenAIRE

    Safarian, Jafar; Engh, Thorvald Abel

    2013-01-01

    Theories on the evaporation of pure substances are reviewed and applied to study vacuum evaporation of pure metals. It is shown that there is good agreement between different theories for weak evaporation, whereas there are differences under intensive evaporation conditions. For weak evaporation, the evaporation coefficient in Hertz-Knudsen equation is 1.66. Vapor velocity as a function of the pressure is calculated applying several theories. If a condensing surface is less than one collision...

  14. Evaporation in hydrology and meteorology

    OpenAIRE

    Brandsma, T.

    1990-01-01

    In this paper the role of evaporation in hydrology and meteorology is discussed, with the emphasis on hydrology. The basic theory of evaporation is given and methods to determine evaporation are presented. Some applications of evaporation studies in literature are given in order to illustrate the theory. Further, special conditions in evaporation are considered, followed by a fotmulation of the difficulties in determining evaporation, The last part of the paper gives a short discussion about ...

  15. Evaporation under vacuum condition

    International Nuclear Information System (INIS)

    Mizuta, Satoshi; Shibata, Yuki; Yuki, Kazuhisa; Hashizume, Hidetoshi; Toda, Saburo; Takase, Kazuyuki; Akimoto, Hajime

    2000-01-01

    In nuclear fusion reactor design, an event of water coolant ingress into its vacuum vessel is now being considered as one of the most probable accidents. In this report, the evaporation under vacuum condition is evaluated by using the evaporation model we have developed. The results show that shock-wave by the evaporation occurs whose behavior strongly depends on the initial conditions of vacuum. And in the case of lower initial pressure and temperature, the surface temp finally becomes higher than other conditions. (author)

  16. Actinide recycle

    Energy Technology Data Exchange (ETDEWEB)

    Till, C; Chang, Y [Argonne National Laboratory, Argonne, IL (United States)

    1990-07-01

    A multitude of studies and assessments of actinide partitioning and transmutation were carried out in the late 1970s and early 1980s. Probably the most comprehensive of these was a study coordinated by Oak Ridge National Laboratory. The conclusions of this study were that only rather weak economic and safety incentives existed for partitioning and transmuting the actinides for waste management purposes, due to the facts that (1) partitioning processes were complicated and expensive, and (2) the geologic repository was assumed to contain actinides for hundreds of thousands of years. Much has changed in the few years since then. A variety of developments now combine to warrant a renewed assessment of the actinide recycle. First of all, it has become increasingly difficult to provide to all parties the necessary assurance that the repository will contain essentially all radioactive materials until they have decayed. Assurance can almost certainly be provided to regulatory agencies by sound technical arguments, but it is difficult to convince the general public that the behavior of wastes stored in the ground can be modeled and predicted for even a few thousand years. From this point of view alone there would seem to be a clear benefit in reducing the long-term toxicity of the high-level wastes placed in the repository.

  17. Actinide recycle

    International Nuclear Information System (INIS)

    Till, C.; Chang, Y.

    1990-01-01

    A multitude of studies and assessments of actinide partitioning and transmutation were carried out in the late 1970s and early 1980s. Probably the most comprehensive of these was a study coordinated by Oak Ridge National Laboratory. The conclusions of this study were that only rather weak economic and safety incentives existed for partitioning and transmuting the actinides for waste management purposes, due to the facts that (1) partitioning processes were complicated and expensive, and (2) the geologic repository was assumed to contain actinides for hundreds of thousands of years. Much has changed in the few years since then. A variety of developments now combine to warrant a renewed assessment of the actinide recycle. First of all, it has become increasingly difficult to provide to all parties the necessary assurance that the repository will contain essentially all radioactive materials until they have decayed. Assurance can almost certainly be provided to regulatory agencies by sound technical arguments, but it is difficult to convince the general public that the behavior of wastes stored in the ground can be modeled and predicted for even a few thousand years. From this point of view alone there would seem to be a clear benefit in reducing the long-term toxicity of the high-level wastes placed in the repository

  18. Formulation and preparation of Hanford Waste Treatment Plant direct feed low activity waste Effluent Management Facility core simulant

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL; Adamson, Duane J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL

    2016-05-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate, LMOGC) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it to the LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of the LMOGC stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste, amongst the other problems such a recycle stream present. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate in the recycled Condensate and is a key outcome of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of this task was to formulate and prepare a simulant of the LAW Melter

  19. CAPSULE REPORT: EVAPORATION PROCESS

    Science.gov (United States)

    Evaporation has been an established technology in the metal finishing industry for many years. In this process, wastewaters containing reusable materials, such as copper, nickel, or chromium compounds are heated, producing a water vapor that is continuously removed and condensed....

  20. Is Municipal Solid Waste Recycling Economically Efficient?

    Science.gov (United States)

    Lavee, Doron

    2007-12-01

    It has traditionally been argued that recycling municipal solid waste (MSW) is usually not economically viable and that only when externalities, long-term dynamic considerations, and/or the entire product life cycle are taken into account, recycling becomes worthwhile from a social point of view. This article explores the results of a wide study conducted in Israel in the years 2000 2004. Our results reveal that recycling is optimal more often than usually claimed, even when externality considerations are ignored. The study is unique in the tools it uses to explore the efficiency of recycling: a computer-based simulation applied to an extensive database. We developed a simulation for assessing the costs of handling and treating MSW under different waste-management systems and used this simulation to explore possible cost reductions obtained by designating some of the waste (otherwise sent to landfill) to recycling. We ran the simulation on data from 79 municipalities in Israel that produce over 60% of MSW in Israel. For each municipality, we were able to arrive at an optimal method of waste management and compare the costs associated with 100% landfilling to the costs born by the municipality when some of the waste is recycled. Our results indicate that for 51% of the municipalities, it would be efficient to adopt recycling, even without accounting for externality costs. We found that by adopting recycling, municipalities would be able to reduce direct costs by an average of 11%. Through interviews conducted with representatives of municipalities, we were also able to identify obstacles to the utilization of recycling, answering in part the question of why actual recycling levels in Israel are lower than our model predicts they should be.

  1. Boilers, evaporators, and condensers

    International Nuclear Information System (INIS)

    Kakac, S.

    1991-01-01

    This book reports on the boilers, evaporators and condensers that are used in power plants including nuclear power plants. Topics included are forced convection for single-phase side heat exchangers, heat exchanger fouling, industrial heat exchanger design, fossil-fuel-fired boilers, once through boilers, thermodynamic designs of fossil fuel-first boilers, evaporators and condensers in refrigeration and air conditioning systems (with respect to reducing CFC's) and nuclear steam generators

  2. Resource Efficient Metal and Material Recycling

    Science.gov (United States)

    Reuter, Markus A.; van Schaik, Antoinette

    Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

  3. Modelling Recycling Targets

    DEFF Research Database (Denmark)

    Hill, Amanda Louise; Leinikka Dall, Ole; Andersen, Frits M.

    2014-01-01

    Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22......% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...... the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish municipalities...

  4. Modeling Evaporation and Particle Assembly in Colloidal Droplets.

    Science.gov (United States)

    Zhao, Mingfei; Yong, Xin

    2017-06-13

    Evaporation-induced assembly of nanoparticles in a drying droplet is of great importance in many engineering applications, including printing, coating, and thin film processing. The investigation of particle dynamics in evaporating droplets can provide fundamental hydrodynamic insight for revealing the processing-structure relationship in the particle self-organization induced by solvent evaporation. We develop a free-energy-based multiphase lattice Boltzmann method coupled with Brownian dynamics to simulate evaporating colloidal droplets on solid substrates with specified wetting properties. The influence of interface-bound nanoparticles on the surface tension and evaporation of a flat liquid-vapor interface is first quantified. The results indicate that the particles at the interface reduce surface tension and enhance evaporation flux. For evaporating particle-covered droplets on substrates with different wetting properties, we characterize the increase of evaporate rate via measuring droplet volume. We find that droplet evaporation is determined by the number density and circumferential distribution of interfacial particles. We further correlate particle dynamics and assembly to the evaporation-induced convection in the bulk and on the surface of droplet. Finally, we observe distinct final deposits from evaporating colloidal droplets with bulk-dispersed and interface-bound particles. In addition, the deposit pattern is also influenced by the equilibrium contact angle of droplet.

  5. A new stationary droplet evaporation model and its validation

    OpenAIRE

    Fang WANG; Jie YAO; Shaofeng YANG; Rui LIU; Jie JIN

    2017-01-01

    The liquid droplet evaporation character is important for not only combustion chamber design process but also high-accuracy spray combustion simulation. In this paper, the suspended droplets’ evaporation character was measured in a quiescent high-temperature environment by micro high-speed camera system. The gasoline and kerosene experimental results are consistent with the reference data. Methanol, common kerosene and aviation kerosene droplet evaporation characteristics, as well as their ev...

  6. Evaporation in hydrology and meteorology

    NARCIS (Netherlands)

    Brandsma, T.

    1990-01-01

    In this paper the role of evaporation in hydrology and meteorology is discussed, with the emphasis on hydrology. The basic theory of evaporation is given and methods to determine evaporation are presented. Some applications of evaporation studies in literature are given in order to illustrate the

  7. Accelerated evaporation of water on graphene oxide.

    Science.gov (United States)

    Wan, Rongzheng; Shi, Guosheng

    2017-03-29

    Using molecular dynamics simulations, we show that the evaporation of nanoscale volumes of water on patterned graphene oxide is faster than that on homogeneous graphene oxide. The evaporation rate of water is insensitive to variation in the oxidation degree of the oxidized regions, so long as the water film is only distributed on the oxidized regions. The evaporation rate drops when the water film spreads onto the unoxidized regions. Further analysis showed that varying the oxidation degree observably changed the interaction between the outmost water molecules and the solid surface, but the total interaction for the outmost water molecules only changed a very limited amount due to the correspondingly regulated water-water interaction when the water film is only distributed on the oxidized regions. When the oxidation degree is too low and some unoxidized regions are also covered by the water film, the thickness of the water film decreases, which extends the lifetime of the hydrogen bonds for the outmost water molecules and lowers the evaporation rate of the water. The insensitivity of water evaporation to the oxidation degree indicates that we only need to control the scale of the unoxidized and oxidized regions for graphene oxide to regulate the evaporation of nanoscale volumes of water.

  8. Mobile evaporator corrosion test results

    International Nuclear Information System (INIS)

    Rozeveld, A.; Chamberlain, D.B.

    1997-05-01

    Laboratory corrosion tests were conducted on eight candidates to select a durable and cost-effective alloy for use in mobile evaporators to process radioactive waste solutions. Based on an extensive literature survey of corrosion data, three stainless steel alloys (304L, 316L, AL-6XN), four nickel-based alloys (825, 625, 690, G-30), and titanium were selected for testing. The corrosion tests included vapor phase, liquid junction (interface), liquid immersion, and crevice corrosion tests on plain and welded samples of candidate materials. Tests were conducted at 80 degrees C for 45 days in two different test solutions: a nitric acid solution. to simulate evaporator conditions during the processing of the cesium ion-exchange eluant and a highly alkaline sodium hydroxide solution to simulate the composition of Tank 241-AW-101 during evaporation. All of the alloys exhibited excellent corrosion resistance in the alkaline test solution. Corrosion rates were very low and localized corrosion was not observed. Results from the nitric acid tests showed that only 316L stainless steel did not meet our performance criteria. The 316L welded interface and crevice specimens had rates of 22.2 mpy and 21.8 mpy, respectively, which exceeds the maximum corrosion rate of 20 mpy. The other welded samples had about the same corrosion resistance as the plain samples. None of the welded samples showed preferential weld or heat-affected zone (HAZ) attack. Vapor corrosion was negligible for all alloys. All of the alloys except 316L exhibited either open-quotes satisfactoryclose quotes (2-20 mpy) or open-quotes excellentclose quotes (<2 mpy) corrosion resistance as defined by National Association of Corrosion Engineers. However, many of the alloys experienced intergranular corrosion in the nitric acid test solution, which could indicate a susceptibility to stress corrosion cracking (SCC) in this environment

  9. CFD Analysis of Evaporation-Condensation Phenomenon In an Evaporation Chamber of Natural Vacuum Solar Desalination

    Science.gov (United States)

    Ambarita, H.; Ronowikarto, A. D.; Siregar, R. E. T.; Setyawan, E. Y.

    2018-01-01

    Desalination technologies is one of solutions for water scarcity. With using renewable energy, like solar energy, wind energy, and geothermal energy, expected will reduce the energy demand. This required study on the modeling and transport parameters determination of natural vacuum solar desalination by using computational fluid dynamics (CFD) method to simulate the model. A three-dimensional case, two-phase model was developed for evaporation-condensation phenomenon in natural vacuum solar desalination. The CFD simulation results were compared with the avalaible experimental data. The simulation results shows inthat there is a phenomenon of evaporation-condensation in an evaporation chamber. From the simulation, the fresh water productivity is 2.21 litre, and from the experimental is 2.1 litre. This study shows there’s an error of magnitude 0.4%. The CFD results also show that, vacuum pressure will degrade the saturation temperature of sea water.

  10. Evaporation of Lennard-Jones fluids.

    Science.gov (United States)

    Cheng, Shengfeng; Lechman, Jeremy B; Plimpton, Steven J; Grest, Gary S

    2011-06-14

    Evaporation and condensation at a liquid/vapor interface are ubiquitous interphase mass and energy transfer phenomena that are still not well understood. We have carried out large scale molecular dynamics simulations of Lennard-Jones (LJ) fluids composed of monomers, dimers, or trimers to investigate these processes with molecular detail. For LJ monomers in contact with a vacuum, the evaporation rate is found to be very high with significant evaporative cooling and an accompanying density gradient in the liquid domain near the liquid/vapor interface. Increasing the chain length to just dimers significantly reduces the evaporation rate. We confirm that mechanical equilibrium plays a key role in determining the evaporation rate and the density and temperature profiles across the liquid/vapor interface. The velocity distributions of evaporated molecules and the evaporation and condensation coefficients are measured and compared to the predictions of an existing model based on kinetic theory of gases. Our results indicate that for both monatomic and polyatomic molecules, the evaporation and condensation coefficients are equal when systems are not far from equilibrium and smaller than one, and decrease with increasing temperature. For the same reduced temperature T/T(c), where T(c) is the critical temperature, these two coefficients are higher for LJ dimers and trimers than for monomers, in contrast to the traditional viewpoint that they are close to unity for monatomic molecules and decrease for polyatomic molecules. Furthermore, data for the two coefficients collapse onto a master curve when plotted against a translational length ratio between the liquid and vapor phase.

  11. Mathematical modeling of wiped-film evaporators

    International Nuclear Information System (INIS)

    Sommerfeld, J.T.

    1976-05-01

    A mathematical model and associated computer program were developed to simulate the steady-state operation of wiped-film evaporators for the concentration of typical waste solutions produced at the Savannah River Plant. In this model, which treats either a horizontal or a vertical wiped-film evaporator as a plug-flow device with no backmixing, three fundamental phenomena are described: sensible heating of the waste solution, vaporization of water, and crystallization of solids from solution. Physical property data were coded into the computer program, which performs the calculations of this model. Physical properties of typical waste solutions and of the heating steam, generally as analytical functions of temperature, were obtained from published data or derived by regression analysis of tabulated or graphical data. Preliminary results from tests of the Savannah River Laboratory semiworks wiped-film evaporators were used to select a correlation for the inside film heat transfer coefficient. This model should be a useful aid in the specification, operation, and control of the full-scale wiped-film evaporators proposed for application under plant conditions. In particular, it should be of value in the development and analysis of feed-forward control schemes for the plant units. Also, this model can be readily adapted, with only minor changes, to simulate the operation of wiped-film evaporators for other conceivable applications, such as the concentration of acid wastes

  12. Frequent Questions on Recycling

    Science.gov (United States)

    This is a list of frequent questions on recycling, broken down into five categories. These are answers to common questions that EPA has received from press and web inquiries. This list is located on the Reduce, Reuse, Recycle website.

  13. Certified Electronics Recyclers

    Science.gov (United States)

    Learn how EPA encourages all electronics recyclers become certified by demonstrating to an accredited, independent third-party auditor and that they meet specific standards to safely recycle and manage electronics.

  14. Evaporation of liquids on chemically patterned surfaces

    NARCIS (Netherlands)

    Vieyra Salas, J.A.; Darhuber, A.A.

    2011-01-01

    We studied evaporation rates of volatile liquids deposited onto chemically patterned surfaces by means of experiments and numerical simulations. We quantified the influence of the droplet geometry, in particular circular, triangular, rectangular and square shapes, as well as the influence of contact

  15. Footprint of recycled water subsidies downwind of Lake Michigan

    Science.gov (United States)

    Continental evaporation is a significant and dynamic flux within the atmospheric water budget, but few methods provide robust observational constraints on the large-scale hydroclimatological and hydroecological impacts of this ‘recycled-water’ flux. We demonstrate a geospatial analysis that provides...

  16. Modeling black hole evaporation

    CERN Document Server

    Fabbri, Alessandro

    2005-01-01

    The scope of this book is two-fold: the first part gives a fully detailed and pedagogical presentation of the Hawking effect and its physical implications, and the second discusses the backreaction problem, especially in connection with exactly solvable semiclassical models that describe analytically the black hole evaporation process. The book aims to establish a link between the general relativistic viewpoint on black hole evaporation and the new CFT-type approaches to the subject. The detailed discussion on backreaction effects is also extremely valuable.

  17. Systematics of evaporation

    International Nuclear Information System (INIS)

    Klots, C.E.

    1991-01-01

    Beginning with rather basic principles, general relations are obtained for evaporative rate constants. These are established both as a function of energy and of temperature. In parallel with this, expressions are developed for the kinetic energy distribution of the separating species. Explicit evaluation of the rate constants in the case of 'chemical' evaporation from an entity containing n monomeric units yields as a typical result k(T)(s -1 )=3.10 13 n 2/3 exp[6/n 1/3 ]exp(-ΔE a (n)/k B T). Experimental evidence in support of this relation is cited. Applications to thermionic emission are also noted. (orig.)

  18. Rethink, Rework, Recycle.

    Science.gov (United States)

    Wrhen, Linda; DiSpezio, Michael A.

    1991-01-01

    Information about the recycling and reuse of plastics, aluminum, steel, glass, and newspapers is presented. The phases of recycling are described. An activity that allows students to separate recyclable materials is included. The objectives, a list of needed materials, and procedure are provided. (KR)

  19. Aluminium beverage can recycling

    Energy Technology Data Exchange (ETDEWEB)

    Lewinski, A von

    1985-08-01

    Canned beverages have become a controversial issue in this era of ecological sensitivity. METALL has already discussed the problem of can recycling. The present article discusses the technical aspects of aluminium can recycling. Two further articles will follow on aluminium can recycling in North America and on the results of European pilot projects.

  20. Modelling Recycling Targets

    DEFF Research Database (Denmark)

    hill, amanda; Leinikka Dall, Ole; Andersen, Frits Møller

    2014-01-01

    % for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...

  1. The recycling is moving

    CERN Multimedia

    GS Department

    2011-01-01

    The recycling site currently situated near building 133 has been transferred to the car park of building 156. The site is identified by the sign “RECYCLING” and the above logo. In this new, more accessible site, you will find recycling bins for the following waste: PET (recyclable plastic bottles); Aluminium cans; Nespresso coffee capsules.  

  2. Essays of leaching in cemented products containing simulated waste from evaporator concentrated of PWR reactor; Ensaios de lixiviacao em produtos cimentados contendo rejeito simulado de concentrado do evaporador de reator PWR

    Energy Technology Data Exchange (ETDEWEB)

    Haucz, Maria Judite A.; Calabria, Jaqueline A. Almeida; Tello, Cledola Cassia O.; Candido, Francisco Donizete; Seles, Sandro Rogerio Novaes, E-mail: hauczmj@cdtn.b, E-mail: jaalmeida@cdtn.b, E-mail: tellocc@cdtn.b, E-mail: fdc@cdtn.b, E-mail: seless@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-10-26

    This paper evaluated the results from leaching resistance essays of cemented products, prepared from three distinct formulations, containing simulated waste of concentrated from the PWR reactor evaporator. The leaching rate is a parameter of qualification of solidified products containing radioactive waste and is determined in accordance with regulation ISO 6961. This procedure evaluates the capacity of transfer organic and inorganic substances presents in the waste through dissolution in the extractor medium. For the case of radioactive waste it is reached the more retention of contaminants in the cemented product, i.e.the lesser value of lixiviation rate. Therefore, this work evaluated among the proposed formulation that one which attend the criterion established in the regulation CNEN-NN-6.09

  3. The continuous similarity model of bulk soil-water evaporation

    Science.gov (United States)

    Clapp, R. B.

    1983-01-01

    The continuous similarity model of evaporation is described. In it, evaporation is conceptualized as a two stage process. For an initially moist soil, evaporation is first climate limited, but later it becomes soil limited. During the latter stage, the evaporation rate is termed evaporability, and mathematically it is inversely proportional to the evaporation deficit. A functional approximation of the moisture distribution within the soil column is also included in the model. The model was tested using data from four experiments conducted near Phoenix, Arizona; and there was excellent agreement between the simulated and observed evaporation. The model also predicted the time of transition to the soil limited stage reasonably well. For one of the experiments, a third stage of evaporation, when vapor diffusion predominates, was observed. The occurrence of this stage was related to the decrease in moisture at the surface of the soil. The continuous similarity model does not account for vapor flow. The results show that climate, through the potential evaporation rate, has a strong influence on the time of transition to the soil limited stage. After this transition, however, bulk evaporation is independent of climate until the effects of vapor flow within the soil predominate.

  4. Flashing evaporation under different pressure levels

    International Nuclear Information System (INIS)

    Liao, Yixiang; Lucas, Dirk; Krepper, Eckhard; Rzehak, Roland

    2013-01-01

    Highlights: • CFD simulation based on two-fluid model for flashing boiling inside a vertical pipe. • Effect of pressure level on the maximum thermal energy available for evaporation. • Effect of presumed bubble size on the onset of flashing as well as evaporation rate. • Effect of pressure level on the critical bubble size that can start stable flashing. • Effect of pressure level on nucleation rate and mechanism. - Abstract: Flashing evaporation of water inside a vertical pipe under four pressure levels is investigated both experimentally and numerically. In the experiment depressurization is realized through a blow-off valve, and the evaporation rate is controlled by the opening rate and degree of the valve. In the CFD simulation phase change is assumed to be caused by thermal heat transfer between steam–water interface and the surrounding water. Consequently, the evaporation rate is determined by heat transfer coefficient, interfacial area density as well as liquid superheat degree. The simulated temporal course of cross-section averaged steam volume fraction is compared with the measured one. It is found that the increasing rate and maximum value of steam volume fraction is over-predicted under low-pressure conditions, which is mainly caused by the neglect of bubble growth in the mono-dispersed simulation. The agreement is notably improved by performing poly-dispersed simulations with the inhomogeneous MUSIG approach (IMUSIG). On the other hand an underestimation of the maximum steam volume fraction is observed in high-pressure cases, since the contribution of nucleation to the total steam generation rate becomes large as the system pressure increases. Reliable models for nucleation rate as well as bubble detachment size are indispensable for reliable predictions. An effect of the system pressure level on the nucleation mechanism is observed in the experiment

  5. Semiclassical approach to black hole evaporation

    International Nuclear Information System (INIS)

    Lowe, D.A.

    1993-01-01

    Black hole evaporation may lead to massive or massless remnants, or naked singularities. This paper investigates this process in the context of two quite different two-dimensional black hole models. The first is the original Callan-Giddings-Harvey-Strominger (CGHS) model, the second is another two-dimensional dilaton-gravity model, but with properties much closer to physics in the real, four-dimensional, world. Numerical simulations are performed of the formation and subsequent evaporation of black holes and the results are found to agree qualitatively with the exactly solved modified CGHS models, namely, that the semiclassical approximation breaks down just before a naked singularity appears

  6. Performance of evaporative condensers

    Energy Technology Data Exchange (ETDEWEB)

    Ettouney, Hisham M.; El-Dessouky, Hisham T.; Bouhamra, Walid; Al-Azmi, Bader

    2001-07-01

    Experimental investigation is conducted to study the performance of evaporative condensers/coolers. The analysis includes development of correlations for the external heat transfer coefficient and the system efficiency. The evaporative condenser includes two finned-tube heat exchangers. The system is designed to allow for operation of a single condenser, two condensers in parallel, and two condensers in series. The analysis is performed as a function of the water-to-air mass flow rate ratio (L/G) and the steam temperature. Also, comparison is made between the performance of the evaporative condenser and same device as an air-cooled condenser. Analysis of the collected data shows that the system efficiency increases at lower L/G ratios and higher steam temperatures. The system efficiency for various configurations for the evaporative condenser varies between 97% and 99%. Lower efficiencies are obtained for the air-cooled condenser, with values between 88% and 92%. The highest efficiency is found for the two condensers in series, followed by two condensers in parallel and then the single condenser. The parallel condenser configuration can handle a larger amount of inlet steam and can provide the required system efficiency and degree of subcooling. The correlation for the system efficiency gives a simple tool for preliminary system design. The correlation developed for the external heat transfer coefficient is found to be consistent with the available literature data. (Author)

  7. Acid fractionation for low level liquid waste cleanup and recycle

    International Nuclear Information System (INIS)

    Gombert, D. II; McIntyre, C.V.; Mizia, R.E.; Schindler, R.E.

    1990-01-01

    At the Idaho Chemical Processing Plant, low level liquid wastes containing small amounts of radionuclides are concentrated via a thermosyphon evaporator for calcination with high level waste, and the evaporator condensates are discharged with other plant wastewater to a percolation pond. Although all existing discharge guidelines are currently met, work has been done to reduce all waste water discharges to an absolute minimum. In this regard, a 15-tray acid fractionation column will be used to distill the mildly acidic evaporator condensates into concentrated nitric acid for recycle in the plant. The innocuous overheads from the fractionator having a pH greater than 2, are superheated and HEPA filtered for atmospheric discharge. Nonvolatile radionuclides are below detection limits. Recycle of the acid not only displaces fresh reagent, but reduces nitrate burden to the environment, and completely eliminates routine discharge of low level liquid wastes to the environment

  8. Dynamical Simulation of Recycling and Particle Fueling in TJ-II Plasmas; Simulacion Dinamica del Reciclado y de la Inyeccion de Particulas en los Plasmas del TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Bruna, D; Ferreira, J A; Tabares, F L; Castejon, F; Guasp, J

    2007-07-20

    With the aim of improving the calculation tools for transport analysis in TJ-II plasmas, in this work we analyze the simplified model for a kinetic equation that ASTRA uses to calculate the neutral particle distribution in the plasma. Next, we act on the boundary conditions for this kinetic equation (particularly on the neutral density in the plasma boundary) so we can simulate the recycling conditions for the TJ-II in a simple way. With the resulting transport models we can easily analyze the sensibility of these plasmas to the cold gas puffing depending on the recycling conditions. These transport models evidence the problem of density control in the TJ-II. Likewise, we estimate the importance of recycling in the plasmas heated by energetic neutral beam injection. The experimentally observed increments in density when the energetic neutrals are injected would respond, according to the calculations here presented, to a large increment of the neutrals influx that cannot be explained by the beam itself. (Author) 22 refs.

  9. Forest evaporation models: Relationships between stand growth and evaporation

    CSIR Research Space (South Africa)

    Le Maitre, David C

    1997-06-01

    Full Text Available The relationships between forest stand structure, growth and evaporation were analysed to determine whether forest evaporation can be estimated from stand growth data. This approach permits rapid assessment of the potential impacts of afforestation...

  10. Slag recycling of irradiated vanadium

    International Nuclear Information System (INIS)

    Gorman, P.K.

    1995-01-01

    An experimental inductoslag apparatus to recycle irradiated vanadium was fabricated and tested. An experimental electroslag apparatus was also used to test possible slags. The testing was carried out with slag materials that were fabricated along with impurity bearing vanadium samples. Results obtained include computer simulated thermochemical calculations and experimentally determined removal efficiencies of the transmutation impurities. Analyses of the samples before and after testing were carried out to determine if the slag did indeed remove the transmutation impurities from the irradiated vanadium

  11. Usage of Recycled Pet

    Directory of Open Access Journals (Sweden)

    A. Ebru Tayyar

    2010-01-01

    Full Text Available The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bottles are commonly used in beverage industry and can be reused after physical and chemical recycling processes. Usage areas of recycled PET have been developed rapidly. Although recycled PET is used in plastic industry, composite industry also provides usage alternatives of recycled PET. Textile is a suitable sector for recycling of some plastics made of polymers too. In this study, the recycling technologies and applications of waste PET bottles have been investigated and scientific works in this area have been summarized.

  12. Optimal control of evaporator and washer plants

    International Nuclear Information System (INIS)

    Niemi, A.J.

    1989-01-01

    Tests with radioactive tracers were used for experimental analysis of a multiple-effect evaporator plant. The residence time distribution of the liquor in each evaporator was described by one or two perfect mixers with time delay and by-pass flow terms. The theoretical model of a single evaporator unit was set up on the basis of its instantaneous heat and mass balances and such models were fitted to the test data. The results were interpreted in terms of physical structures of the evaporators. Further model parameters were evaluated by conventional step tests and by measurements of process variables at one or more steady states. Computer simulation and comparison with the experimental results showed that the model produces a satisfactory response to solids concentration input and could be extended to cover the steam feed and liquor flow inputs. An optimal feedforward control algorithm was developed for a two unit, co-current evaporator plant. The control criterion comprised the deviations of the final solids content of liquor and the consumption of fresh steam, from their optimal steady-state values. In order to apply the algorithm, the model of the solids in liquor was reduced to two nonlinear differential equations. (author)

  13. Evaporation rate of water in hydrophobic confinement.

    Science.gov (United States)

    Sharma, Sumit; Debenedetti, Pablo G

    2012-03-20

    The drying of hydrophobic cavities is believed to play an important role in biophysical phenomena such as the folding of globular proteins, the opening and closing of ligand-gated ion channels, and ligand binding to hydrophobic pockets. We use forward flux sampling, a molecular simulation technique, to compute the rate of capillary evaporation of water confined between two hydrophobic surfaces separated by nanoscopic gaps, as a function of gap, surface size, and temperature. Over the range of conditions investigated (gaps between 9 and 14 Å and surface areas between 1 and 9 nm(2)), the free energy barrier to evaporation scales linearly with the gap between hydrophobic surfaces, suggesting that line tension makes the predominant contribution to the free energy barrier. The exponential dependence of the evaporation rate on the gap between confining surfaces causes a 10 order-of-magnitude decrease in the rate when the gap increases from 9 to 14 Å. The computed free energy barriers are of the order of 50 kT and are predominantly enthalpic. Evaporation rates per unit area are found to be two orders of magnitude faster in confinement by the larger (9 nm(2)) than by the smaller (1 nm(2)) surfaces considered here, at otherwise identical conditions. We show that this rate enhancement is a consequence of the dependence of hydrophobic hydration on the size of solvated objects. For sufficiently large surfaces, the critical nucleus for the evaporation process is a gap-spanning vapor tube.

  14. Convection-enhanced water evaporation

    OpenAIRE

    B. M. Weon; J. H. Je; C. Poulard

    2011-01-01

    Water vapor is lighter than air; this can enhance water evaporation by triggering vapor convection but there is little evidence. We directly visualize evaporation of nanoliter (2 to 700 nL) water droplets resting on silicon wafer in calm air using a high-resolution dual X-ray imaging method. Temporal evolutions of contact radius and contact angle reveal that evaporation rate linearly changes with surface area, indicating convective (instead of diffusive) evaporation in nanoliter water droplet...

  15. Evaporative behavior of carbon with MPD Arc Jet

    Energy Technology Data Exchange (ETDEWEB)

    Sukegawa, Toshio; Madarame, Haruki; Okamoto, Koji [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1996-10-01

    Using the Magneto-Plasma-Dynamic Arc Jet (MPD Arc Jet) device, the plasma-material interaction during simulated plasma disruption was experimentally investigated. To clarify the effects of the evaporation, the isotropic graphite was used as a target. The thermal conductivity of the isotropic graphite was much higher than that of the pyrolytic graphite, resulting in smaller evaporation. The light intensity distribution during the simulated disruption for the isotropic graphite was quite different from that for the pyrolytic graphite. (author)

  16. Impact, absorption and evaporation of raindrops on building facades

    DEFF Research Database (Denmark)

    Abuku, Masaru; Janssen, Hans; Poesen, Jean

    2009-01-01

    . Finally, the experimental and numerical data were used in a more precise three-dimensional simulation of impact, absorption and evaporation of random and discrete wind-driven raindrops. This was compared With the common one-dimensional simulation of absorption and evaporation at the facade considering...... a continuous uniform rain load as boundary condition, and significant differences between the two approaches were observed. (C) 2008 Elsevier Ltd. All rights reserved....

  17. A new stationary droplet evaporation model and its validation

    Directory of Open Access Journals (Sweden)

    Fang WANG

    2017-08-01

    Full Text Available The liquid droplet evaporation character is important for not only combustion chamber design process but also high-accuracy spray combustion simulation. In this paper, the suspended droplets’ evaporation character was measured in a quiescent high-temperature environment by micro high-speed camera system. The gasoline and kerosene experimental results are consistent with the reference data. Methanol, common kerosene and aviation kerosene droplet evaporation characteristics, as well as their evaporation rate changing with temperature, were obtained. The evaporation rate experimental data were compared with the prediction result of Ranz-Marshall boiling temperature model (RMB, Ranz-Marshall low-temperature model (RML, drift flux model (DFM, mass analogy model (MAM, and stagnant film model (SFM. The disparity between the experimental data and the model prediction results was mainly caused by the neglect of the natural convection effect, which was never introduced into the droplet evaporation concept. A new droplet evaporation model with consideration of natural convection buoyancy force effect was proposed in this paper. Under the experimental conditions in this paper, the calculation results of the new droplet evaporation model were agreed with the experimental data for kerosene, methanol and other fuels, with less than 20% relative deviations. The relative deviations between the new evaporation model predictions for kerosene and the experimental data from the references were within 10%.

  18. Artificial weathering of oils by rotary evaporator

    International Nuclear Information System (INIS)

    Fieldhouse, B.; Hollebone, B.P.; Singh, N.R.; Tong, T.S.; Mullin, J.

    2009-01-01

    Oil weathering has a considerable affect on the behaviour, impact and ultimate fate of an oil spill. As such, efforts have been made to study weathering as a whole using bench-scale procedures. The studies are generally divided into individual processes where the effect of other major processes are introduce as an amended sample input rather than a concurrent process. The weathering process that has the greatest effect immediately following an oil spill is evaporation, particularly for lighter oils. The rotary evaporator apparatus offers a convenient means of producing artificially weathered oil for laboratory studies. This paper reported on a study that examined the representativeness of samples obtained by this method compared to pan evaporation and the impact of changes to the apparatus or method parameters on sample chemistry. Experiments were performed on Alberta Sweet Mixed Blend no. 5 in a rotary evaporator under varying conditions of temperature and air flow at ambient pressure using 2 apparatus. The rate of mass loss increased with temperature and air flow rate as expected, but the quantitative relationships could not be defined from the data due to contributions by other uncontrolled factors. It was concluded that the rotary evaporator is not suited for evaporation rate studies, but rather for producing samples suitable for use in other studies. Chemical analysis showed that the relative abundance distributions of target n-alkane hydrocarbons varied with the degree of weathering of an oil in a consistent manner at ambient pressure, regardless of the temperature, rate of air exchange or other factors related to the apparatus and procedure. The composition of the artificially weathered oil was also consistent with that from an open pan simulation of a weathered oil slick. Loss of water content varied with the conditions of evaporation because of the differential rates of evaporation due to relative humidity considerations. It was concluded that weathering

  19. The importance of recycling - Responsible recycling

    International Nuclear Information System (INIS)

    Svensson, Joens Petter

    2014-01-01

    7 times the total emissions from Sweden are saved each year by the recycling industry. It reduces CO 2 emissions and saves the environment. In fact it annually reduces global CO 2 emissions by 500 million tons, which is more than what is being emitted by the world wide aviation industry. Recycling of iron and steel saves 74% energy and reduces water and air pollution by respectively 76% and 86%, compared to primary production. It provides new raw materials and contributes to save energy. There's no sense in producing goods in a permanent material like plastics, that's supposed to be used only once. It's a huge waste of resources. Today the recycling industry provides half of the world's raw materials and this figure is set to increase. It's about environmentally sound management of resources. It's about plain common sense. There has to be a political willingness to facilitate recycling in every way. And from a corporate perspective social responsibility is becoming an increasingly important competitive edge. This is also a communication issue, it has to be a fact that is well known to the market when a company is doing valuable environmental work. We also need a well functioning global market with easy to understand regulations to facilitate global trade. The global demand for recycled materials should influence their collection and use. Fraud and theft has also to be kept at bay which calls for a close collaboration between organizations such as The International Chamber of Commerce, The International Trade Council and the International Maritime Bureau of the commercial crime services. Increasing recycling is the only way to go if we want to minimize our effect on the environment. We have to remember that recycling is essential for the environment. An increase would be a tremendous help to reduce the green house effect. Increasing recycling is not rocket science. We know how to do it, we just have to decide to go through with it

  20. Lamps recycling aiming at the environment preservation

    International Nuclear Information System (INIS)

    Yamachita, Roberto Akira; Gama, Paulo Henrique R. Pereira; Haddad, Jamil; Santos, Afonso H. Moreira; Guardia, Eduardo C.

    1999-01-01

    The article discusses the following issues of lamps recycling in Brazil: mercury lamps recycling, recycling potential, energy conservation and environmental impacts, enterprises lamps recycling, and incentives policy

  1. Recycling of concrete

    International Nuclear Information System (INIS)

    Halaszovich, S.

    1988-01-01

    The paper reviews potentials and problems of disposal or recycling of concrete removed from nuclear installations. Due to the difficulties in determining radioactivity limits that are compatible with utilization of recycled material in practice, a method is proposed that takes into account inhalation of dusts, as occurring during the reprocessing or recycling of the concrete, for instance in road building. This method is based on the maximum permissible radioactivity uptake by inhalation of a nuclide mixture of unknown composition. (RB) [de

  2. Benchmarking survey for recycling.

    Energy Technology Data Exchange (ETDEWEB)

    Marley, Margie Charlotte; Mizner, Jack Harry

    2005-06-01

    This report describes the methodology, analysis and conclusions of a comparison survey of recycling programs at ten Department of Energy sites including Sandia National Laboratories/New Mexico (SNL/NM). The goal of the survey was to compare SNL/NM's recycling performance with that of other federal facilities, and to identify activities and programs that could be implemented at SNL/NM to improve recycling performance.

  3. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    Ashlines: To promote and support the commercially viable and environmentally sound recycling of coal combustion byproducts for productive uses through scientific research, development, and field testing.

  4. Mixed plastics recycling technology

    CERN Document Server

    Hegberg, Bruce

    1995-01-01

    Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.

  5. Maldistribution in airewater heat pump evaporators. Part 1: Effects on evaporator, heat pump and system level

    DEFF Research Database (Denmark)

    Mader, Gunda; Palm, Björn; Elmegaard, Brian

    2015-01-01

    This paper presents an approach to quantify the effect of evaporator maldistribution onoperating costs of air-water heat pumps. In the proposed simulation model maldistributionis induced by two parameters describing refrigerant phase and air flow distribution.Annual operating costs are calculated...

  6. Evaporation of tiny water aggregation on solid surfaces with different wetting properties.

    Science.gov (United States)

    Wang, Shen; Tu, Yusong; Wan, Rongzheng; Fang, Haiping

    2012-11-29

    The evaporation of a tiny amount of water on the solid surface with different wettabilities has been studied by molecular dynamics simulations. From nonequilibrium MD simulations, we found that, as the surface changed from hydrophobic to hydrophilic, the evaporation speed did not show a monotonic decrease as intuitively expected, but increased first, and then decreased after it reached a maximum value. The analysis of the simulation trajectory and calculation of the surface water interaction illustrate that the competition between the number of water molecules on the water-gas surface from where the water molecules can evaporate and the potential barrier to prevent those water molecules from evaporating results in the unexpected behavior of the evaporation. This finding is helpful in understanding the evaporation on biological surfaces, designing artificial surfaces of ultrafast water evaporating, or preserving water in soil.

  7. Mathematical model of compact type evaporator

    Science.gov (United States)

    Borovička, Martin; Hyhlík, Tomáš

    2018-06-01

    In this paper, development of the mathematical model for evaporator used in heat pump circuits is covered, with focus on air dehumidification application. Main target of this ad-hoc numerical model is to simulate heat and mass transfer in evaporator for prescribed inlet conditions and different geometrical parameters. Simplified 2D mathematical model is developed in MATLAB SW. Solvers for multiple heat and mass transfer problems - plate surface temperature, condensate film temperature, local heat and mass transfer coefficients, refrigerant temperature distribution, humid air enthalpy change are included as subprocedures of this model. An automatic procedure of data transfer is developed in order to use results of MATLAB model in more complex simulation within commercial CFD code. In the end, Proper Orthogonal Decomposition (POD) method is introduced and implemented into MATLAB model.

  8. Thermodynamic Modeling of Savannah River Evaporators

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.F.

    2001-08-02

    A thermodynamic model based on the code SOLGASMIX is developed to calculate phase equilibrium in evaporators and related tank wastes at the Savannah River Site (SRS). This model uses the Pitzer method to calculate activity coefficients, and many of the required Pitzer parameters have been determined in the course of this work. Principal chemical species in standard SRS simulant solutions are included, and the temperature range for most parameters has been extended above 100 C. The SOLGASMIX model and calculations using the code Geochemists Workbench are compared to actual solubility data including silicate, aluminate, and aluminosilicate solutions. In addition, SOLGASMIX model calculations are also compared to transient solubility data involving SRS simulant solutions. These comparisons indicate that the SOLGASMIX predictions closely match reliable data over the range of temperature and solution composition expected in the SRS evaporator and related tanks. Predictions using the Geochemists Workbench may be unreliable, due primarily to the use of an inaccurate activity coefficient model.

  9. New mechanism of cluster-field evaporation in rf breakdown

    Directory of Open Access Journals (Sweden)

    Z. Insepov

    2004-12-01

    Full Text Available Using a simple field evaporation model and molecular dynamics simulations of nanoscale copper tip evolution in a high electric field gradient typical for linacs, we have studied a new mechanism for rf-field evaporation. The mechanism consists of simultaneous (collective field evaporation of a large group of tip atoms in high-gradient fields. Thus, evaporation of large clusters is energetically more favorable when compared with the conventional, “one-by-one” mechanism. The studied mechanism could also be considered a new mechanism for the triggering of rf-vacuum breakdown. This paper discusses the mechanism and the experimental data available for electric field evaporation of field-emission microscopy tips.

  10. Using evaporation to control capillary instabilities in micro-systems.

    Science.gov (United States)

    Ledesma-Aguilar, Rodrigo; Laghezza, Gianluca; Yeomans, Julia M; Vella, Dominic

    2017-12-06

    The instabilities of fluid interfaces represent both a limitation and an opportunity for the fabrication of small-scale devices. Just as non-uniform capillary pressures can destroy micro-electrical mechanical systems (MEMS), so they can guide the assembly of novel solid and fluid structures. In many such applications the interface appears during an evaporation process and is therefore only present temporarily. It is commonly assumed that this evaporation simply guides the interface through a sequence of equilibrium configurations, and that the rate of evaporation only sets the timescale of this sequence. Here, we use Lattice-Boltzmann simulations and a theoretical analysis to show that, in fact, the rate of evaporation can be a factor in determining the onset and form of dynamical capillary instabilities. Our results shed light on the role of evaporation in previous experiments, and open the possibility of exploiting diffusive mass transfer to directly control capillary flows in MEMS applications.

  11. Miniature electron bombardment evaporation source: evaporation rate measurement

    International Nuclear Information System (INIS)

    Nehasil, V.; Masek, K.; Matolin, V.; Moreau, O.

    1997-01-01

    Miniature electron beam evaporation sources which operate on the principle of vaporization of source material, in the form of a tip, by electron bombardment are produced by several companies specialized in UHV equipment. These sources are used primarily for materials that are normally difficult to deposit due to their high evaporation temperature. They are appropriate for special applications such as heteroepitaxial thin film growth requiring a very low and well controlled deposition rate. A simple and easily applicable method of evaporation rate control is proposed. The method is based on the measurement of ion current produced by electron bombardment of evaporated atoms. The absolute evaporation flux values were measured by means of the Bayard-Alpert ion gauge, which enabled the ion current vs evaporation flux calibration curves to be plotted. (author). 1 tab., 4 figs., 6 refs

  12. PFR evaporator leak

    International Nuclear Information System (INIS)

    Smedley, J.A.

    1975-01-01

    PFR has three heat removal circuits each one having an evaporator, superheater, reheater; all separate units. The status of the system was that circuit No 3 was steaming with 10 MW thermal nuclear power; No 1 circuit was filled with sodium but with the evaporator awaiting modification to cure gas entrainment problems already reported. The leak was in No 2 circuit and was located in the evaporator unit. The evaporator is rated at 120 M thermal at full power and as such is a large unit. The circuit was filled with both sodium and water for the first time three weeks before the conference so it was recent history being reported and therefore any figures quoted should be taken as indicative only. The history of the steam generator was that it was built at works to a very high standard and underwent all the usual tests of strength, inspection of welds and helium leak testing. The steam generator is of U tube design with a tube plate to which the boiler tubes are welded, with all the welds in one of two gas spaces. The inlet and outlet sides are separated by a baffle and the salient features are illustrated in the attached figure. The unit achieved a leak tightness better than the detection limit in the helium leak test at works. This limit was assessed as being less than an equivalent leak of 10 -6 g/s water under steam generator service conditions. However even though all the steam generator units passed this test at works a further test was carried out when the circuits had been completed. The test was carried out during commissioning after sodium filling and with the units hot. The method was to introduce a mixture of helium/ argon at 500 pounds/square inch into the water side of the steam generators and measure the helium concentration in the sodium side gas spaces of the circuit. The test lasted many days and under these conditions the sensitivity is such that a leak equivalent to somewhere between 10 -7 to 10 -6 g/s equivalent water leak could be detected, i

  13. PFR evaporator leak

    Energy Technology Data Exchange (ETDEWEB)

    Smedley, J A

    1975-07-01

    PFR has three heat removal circuits each one having an evaporator, superheater, reheater; all separate units. The status of the system was that circuit No 3 was steaming with 10 MW thermal nuclear power; No 1 circuit was filled with sodium but with the evaporator awaiting modification to cure gas entrainment problems already reported. The leak was in No 2 circuit and was located in the evaporator unit. The evaporator is rated at 120 M thermal at full power and as such is a large unit. The circuit was filled with both sodium and water for the first time three weeks before the conference so it was recent history being reported and therefore any figures quoted should be taken as indicative only. The history of the steam generator was that it was built at works to a very high standard and underwent all the usual tests of strength, inspection of welds and helium leak testing. The steam generator is of U tube design with a tube plate to which the boiler tubes are welded, with all the welds in one of two gas spaces. The inlet and outlet sides are separated by a baffle and the salient features are illustrated in the attached figure. The unit achieved a leak tightness better than the detection limit in the helium leak test at works. This limit was assessed as being less than an equivalent leak of 10{sup -6} g/s water under steam generator service conditions. However even though all the steam generator units passed this test at works a further test was carried out when the circuits had been completed. The test was carried out during commissioning after sodium filling and with the units hot. The method was to introduce a mixture of helium/ argon at 500 pounds/square inch into the water side of the steam generators and measure the helium concentration in the sodium side gas spaces of the circuit. The test lasted many days and under these conditions the sensitivity is such that a leak equivalent to somewhere between 10{sup -7} to 10{sup -6} g/s equivalent water leak could be

  14. Evaporation and Antievaporation Instabilities

    Directory of Open Access Journals (Sweden)

    Andrea Addazi

    2017-10-01

    Full Text Available We review (antievaporation phenomena within the context of quantum gravity and extended theories of gravity. The (antievaporation effect is an instability of the black hole horizon discovered in many different scenarios: quantum dilaton-gravity, f ( R -gravity, f ( T -gravity, string-inspired black holes, and brane-world cosmology. Evaporating and antievaporating black holes seem to have completely different thermodynamical features compared to standard semiclassical black holes. The purpose of this review is to provide an introduction to conceptual and technical aspects of (antievaporation effects, while discussing problems that are still open.

  15. Water Recycling in Australia

    Directory of Open Access Journals (Sweden)

    Ross Young

    2011-09-01

    Full Text Available Australia is the driest inhabited continent on earth and, more importantly, experiences the most variable rainfall of all the continents on our planet. The vast majority of Australians live in large cities on the coast. Because wastewater treatments plants were all located near the coast, it was thought that large scale recycling would be problematic given the cost of infrastructure and pumping required to establish recycled water schemes. This all changed when Australia experienced a decade of record low rainfall and water utilities were given aggressive targets to increase the volume of water recycled. This resulted in recycled water being accepted as a legitimate source of water for non-drinking purposes in a diversified portfolio of water sources to mitigate climate risk. To ensure community support for recycled water, Australia lead the world in developing national guidelines for the various uses of recycled water to ensure the protection of public health and the environment. Australia now provides a great case study of the developments in maximizing water recycling opportunities from policy, regulatory and technological perspectives. This paper explores the evolution in thinking and how approaches to wastewater reuse has changed over the past 40 years from an effluent disposal issue to one of recognizing wastewater as a legitimate and valuable resource. Despite recycled water being a popular choice and being broadly embraced, the concept of indirect potable reuse schemes have lacked community and political support across Australia to date.

  16. Reuse, Reduce, Recycle.

    Science.gov (United States)

    Briscoe, Georgia

    1991-01-01

    Discussion of recycling paper in law libraries is also applicable to other types of libraries. Results of surveys of law libraries that investigated recycling practices in 1987 and again in 1990 are reported, and suggestions for reducing the amount of paper used and reusing as much as possible are offered. (LRW)

  17. Length and time scales of atmospheric moisture recycling

    Directory of Open Access Journals (Sweden)

    R. J. van der Ent

    2011-03-01

    Full Text Available It is difficult to quantify the degree to which terrestrial evaporation supports the occurrence of precipitation within a certain study region (i.e. regional moisture recycling due to the scale- and shape-dependence of regional moisture recycling ratios. In this paper we present a novel approach to quantify the spatial and temporal scale of moisture recycling, independent of the size and shape of the region under study. In contrast to previous studies, which essentially used curve fitting, the scaling laws presented by us follow directly from the process equation. thus allowing a fair comparison between regions and seasons. The calculation is based on ERA-Interim reanalysis data for the period 1999 to 2008. It is shown that in the tropics or in mountainous terrain the length scale of recycling can be as low as 500 to 2000 km. In temperate climates the length scale is typically between 3000 to 5000 km whereas it amounts to more than 7000 km in desert areas. The time scale of recycling ranges from 3 to 20 days, with the exception of deserts, where it is much longer. The most distinct seasonal differences can be observed over the Northern Hemisphere: in winter, moisture recycling is insignificant, whereas in summer it plays a major role in the climate. The length and time scales of atmospheric moisture recycling can be useful metrics to quantify local climatic effects of land use change.

  18. Evaporation of inclined water droplets

    Science.gov (United States)

    Kim, Jin Young; Hwang, In Gyu; Weon, Byung Mook

    2017-01-01

    When a drop is placed on a flat substrate tilted at an inclined angle, it can be deformed by gravity and its initial contact angle divides into front and rear contact angles by inclination. Here we study on evaporation dynamics of a pure water droplet on a flat solid substrate by controlling substrate inclination and measuring mass and volume changes of an evaporating droplet with time. We find that complete evaporation time of an inclined droplet becomes longer as gravitational influence by inclination becomes stronger. The gravity itself does not change the evaporation dynamics directly, whereas the gravity-induced droplet deformation increases the difference between front and rear angles, which quickens the onset of depinning and consequently reduces the contact radius. This result makes the evaporation rate of an inclined droplet to be slow. This finding would be important to improve understanding on evaporation dynamics of inclined droplets. PMID:28205642

  19. On the application of the classic Kessler and Berry schemes in Large Eddy Simulation models with a particular emphasis on cloud autoconversion, the onset time of precipitation and droplet evaporation

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    Full Text Available Many Large Eddy Simulation (LES models use the classic Kessler parameterisation either as it is or in a modified form to model the process of cloud water autoconversion into precipitation. The Kessler scheme, being linear, is particularly useful and is computationally straightforward to implement. However, a major limitation with this scheme lies in its inability to predict different autoconversion rates for maritime and continental clouds. In contrast, the Berry formulation overcomes this difficulty, although it is cubic. Due to their different forms, it is difficult to match the two solutions to each other. In this paper we single out the processes of cloud conversion and accretion operating in a deep model cloud and neglect the advection terms for simplicity. This facilitates exact analytical integration and we are able to derive new expressions for the time of onset of precipitation using both the Kessler and Berry formulations. We then discuss the conditions when the two schemes are equivalent. Finally, we also critically examine the process of droplet evaporation within the framework of the classic Kessler scheme. We improve the existing parameterisation with an accurate estimation of the diffusional mass transport of water vapour. We then demonstrate the overall robustness of our calculations by comparing our results with the experimental observations of Beard and Pruppacher, and find excellent agreement.

    Key words. Atmospheric composition and structure · Cloud physics and chemistry · Pollution · Meteorology and atmospheric dynamics · Precipitation

  20. On the application of the classic Kessler and Berry schemes in Large Eddy Simulation models with a particular emphasis on cloud autoconversion, the onset time of precipitation and droplet evaporation

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    1998-05-01

    Full Text Available Many Large Eddy Simulation (LES models use the classic Kessler parameterisation either as it is or in a modified form to model the process of cloud water autoconversion into precipitation. The Kessler scheme, being linear, is particularly useful and is computationally straightforward to implement. However, a major limitation with this scheme lies in its inability to predict different autoconversion rates for maritime and continental clouds. In contrast, the Berry formulation overcomes this difficulty, although it is cubic. Due to their different forms, it is difficult to match the two solutions to each other. In this paper we single out the processes of cloud conversion and accretion operating in a deep model cloud and neglect the advection terms for simplicity. This facilitates exact analytical integration and we are able to derive new expressions for the time of onset of precipitation using both the Kessler and Berry formulations. We then discuss the conditions when the two schemes are equivalent. Finally, we also critically examine the process of droplet evaporation within the framework of the classic Kessler scheme. We improve the existing parameterisation with an accurate estimation of the diffusional mass transport of water vapour. We then demonstrate the overall robustness of our calculations by comparing our results with the experimental observations of Beard and Pruppacher, and find excellent agreement.Key words. Atmospheric composition and structure · Cloud physics and chemistry · Pollution · Meteorology and atmospheric dynamics · Precipitation

  1. Continuous cell recycle fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Warren, R K; Hill, G A; MacDonald, D G

    1991-10-01

    A cell recycle fermentor using a cross-flow membrane filter has been operated for extended periods. Productivities as high as 70 g/l/h were obtained at a cell concentration of 120 g/l and a product concentration of 70 g/l. The experimental results were then fitted to previously derived biokinetic models (Warren et al., 1990) for a continuous stirred tank fermentor. A good fit for growth rate was found and the cell yield was shown to decrease with product concentration. The product yield, however, was found to remain nearly constant at all cell, substrate and product concentrations. These biokinetics, along with a previous model for the membrane filter (Warren et al., 1991) were then used in a simulalation to estimate the costs of producing ethanol in a large scale system. This simulation was optimized using a variant of the steepest descent method from which a fermentor inlet substrate concentration of 150 g/l and a net cost of $CAN 253.5/1000 L ethanol were projected. From a sensitivity analysis, the yield parameters were found to have the greatest effect on ethanol net cost of the fermentor parameters, while the operating costs and the profit was found to be most sensitive to the wheat raw material cost and to the dried grains by-product value. 55 refs., 11 tabs., 7figs.

  2. 242-A evaporator hazards assessment

    International Nuclear Information System (INIS)

    Johnson, T.L.

    1998-01-01

    This document establishes the technical basis in support of Emergency Planning activities for the 242-A Evaporator, on the Hanford Site. Through this document the technical basis for the development of facility specific Emergency Action Levels and the Emergency Planning Zone is demonstrated. The evaporator sues a conventional, forced-circulation, vacuum evaporation system to concentrate radioactive waste solutions. This concentration results in the reduction in waste volume and reduces the number of double-shelled tanks required to store the waste

  3. Probing loop quantum gravity with evaporating black holes.

    Science.gov (United States)

    Barrau, A; Cailleteau, T; Cao, X; Diaz-Polo, J; Grain, J

    2011-12-16

    This Letter aims at showing that the observation of evaporating black holes should allow the usual Hawking behavior to be distinguished from loop quantum gravity (LQG) expectations. We present a full Monte Carlo simulation of the evaporation in LQG and statistical tests that discriminate between competing models. We conclude that contrarily to what was commonly thought, the discreteness of the area in LQG leads to characteristic features that qualify evaporating black holes as objects that could reveal quantum gravity footprints. © 2011 American Physical Society

  4. Water Evaporation and Conformational Changes from Partially Solvated Ubiquitin

    Directory of Open Access Journals (Sweden)

    Saravana Prakash Thirumuruganandham

    2010-01-01

    Full Text Available Using molecular dynamics simulation, we study the evaporation of water molecules off partially solvated ubiquitin. The evaporation and cooling rates are determined for a molecule at the initial temperature of 300 K. The cooling rate is found to be around 3 K/ns, and decreases with water temperature in the course of the evaporation. The conformation changes are monitored by studying a variety of intermediate partially solvated ubiquitin structures. We find that ubiquitin shrinks with decreasing hydration shell and exposes more of its hydrophilic surface area to the surrounding.

  5. Development And Initial Testing Of Off-Gas Recycle Liquid From The WTP Low Activity Waste Vitrification Process - 14333

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.; Taylor-Pashow, Kathryn M.; Adamson, Duane J.; Crawford, Charles L.; Morse, Megan M.

    2014-01-07

    The Waste Treatment and Immobilization Plant (WTP) process flow was designed to pre-treat feed from the Hanford tank farms, separate it into a High Level Waste (HLW) and Low Activity Waste (LAW) fraction and vitrify each fraction in separate facilities. Vitrification of the waste generates an aqueous condensate stream from the off-gas processes. This stream originates from two off-gas treatment unit operations, the Submerged Bed Scrubber (SBS) and the Wet Electrospray Precipitator (WESP). Currently, the baseline plan for disposition of the stream from the LAW melter is to recycle it to the Pretreatment facility where it gets evaporated and processed into the LAW melter again. If the Pretreatment facility is not available, the baseline disposition pathway is not viable. Additionally, some components in the stream are volatile at melter temperatures, thereby accumulating to high concentrations in the scrubbed stream. It would be highly beneficial to divert this stream to an alternate disposition path to alleviate the close-coupled operation of the LAW vitrification and Pretreatment facilities, and to improve long-term throughput and efficiency of the WTP system. In order to determine an alternate disposition path for the LAW SBS/WESP Recycle stream, a range of options are being studied. A simulant of the LAW Off-Gas Condensate was developed, based on the projected composition of this stream, and comparison with pilot-scale testing. The primary radionuclide that vaporizes and accumulates in the stream is Tc-99, but small amounts of several other radionuclides are also projected to be present in this stream. The processes being investigated for managing this stream includes evaporation and radionuclide removal via precipitation and adsorption. During evaporation, it is of interest to investigate the formation of insoluble solids to avoid scaling and plugging of equipment. Key parameters for radionuclide removal include identifying effective precipitation or ion

  6. Turkish Undergraduates' Misconceptions of Evaporation, Evaporation Rate, and Vapour Pressure

    Science.gov (United States)

    Canpolat, Nurtac

    2006-01-01

    This study focused on students' misconceptions related to evaporation, evaporation rate, and vapour pressure. Open-ended diagnostic questions were used with 107 undergraduates in the Primary Science Teacher Training Department in a state university in Turkey. In addition, 14 students from that sample were interviewed to clarify their written…

  7. Molecular investigation of evaporation of biodroplets containing single-strand DNA on graphene surface.

    Science.gov (United States)

    Akbari, Fahimeh; Foroutan, Masumeh

    2018-02-14

    In this study, the water droplet behaviour of four different types of single-strand DNA with homogeneous base sequence on a graphene substrate during evaporation of the droplet was investigated using molecular dynamics (MD) simulation. The simulation results indicated that the evaporation depended on the DNA sequence. The observed changes can be divided into four parts: (i) vaporization mode, (ii) evaporation flux, (iii) mechanism of single-strand placement on the surface, and (iv) consideration of remaining single strands after evaporation. Our simulation observations indicated different evaporation modes for thymine biodroplets as compared to those for other biodroplets. The evaporation of the thymine biodroplets occurred with an increase in the contact angle, while that of the other biodroplets occur in a constant contact angle mode. Moreover, thymine biodroplets generate the lowest contact line compared to other single strands, and it is always placed far away from the centre of the droplets during evaporation. Investigating variations in the evaporation flux shows that thymine has the highest evaporation flux and guanine has the lowest. Moreover, during initial evaporation, the flux of evaporation increases at the triple point of the biodroplets containing thymine single strands, while it decreases in the other biodroplets. The following observation was obtained from the study of the placement of single strands on the substrate: guanine and thymine interacted slower than other single strands during evaporation with graphene, adenine single strand had a higher folding during evaporation, and guanine single strand showed the lowest end-to-end distance. The investigation of single-strand DNA after evaporation shows that adenine produces the most stable structure at the end of evaporation. In addition, cytosine is the most stretched single-strand DNA due to its lack of internal π-π stacking and hydrogen bonding. Therefore, cytosine single strand is more

  8. Recycling of used oil

    International Nuclear Information System (INIS)

    Vipulanandan, C.; Ghurye, G.

    1992-01-01

    This paper reports on used oil which is a valuable resource that should be recycled. Recycling used oil saves energy and natural resources. Used oil can be reprocessed and used as fuel in industrial burners and boilers. Unfortunately, more than 400 million gallons/year of used oil is lost through widespread dumping, partly due to lack of effective recycling procedures. Although used oil is not currently a federally listed hazardous waste, the U.S. EPA has proposed to list it as a hazardous waste, which will make recycling of used oil even more attractive. Laboratory samples, representing used oil, were used for detailed parametric studies and to determine the limitation of extending some of the current physical separation techniques such as sedimentation and centrifuging developed for oil-water and solid-liquid separation

  9. Recycling of Metals

    DEFF Research Database (Denmark)

    Damgaard, Anders; Christensen, Thomas Højlund

    2011-01-01

    Metals like iron and aluminium are produced from mineral ore and used for a range of products, some of which have very short lifetimes and thus constitute a major fraction of municipal waste. Packaging in terms of cans, foils and containers are products with a short lifetime. Other products like...... appliances, vehicles and buildings, containing iron and aluminium metals, have long lifetimes before they end up in the waste stream. The recycling of production waste and postconsumer metals has a long history in the metal industry. Some metal smelters are today entirely based on scarp metals. This chapter...... describes briefly how iron and aluminium are produced and how scrap metal is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of metal recycling. Copper and other metals are also found in waste but in much smaller...

  10. Reduce, reuse and recycle

    CSIR Research Space (South Africa)

    Afrika, M

    2010-10-01

    Full Text Available The adoption of the internationally accepted waste management hierarchy (Sakai et al, 1996) into South African policy has changed the focus from “end of pipe” waste management towards waste minimisation (reuse, recycling and cleaner production...

  11. Recycling of Glass

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

  12. A Practical Recycling Project . . .

    Science.gov (United States)

    Durant, Raymond H.; Mikuska, James M.

    1973-01-01

    Descirbes a school district's recycling program of aluminum lunch trays that are collected after their use. The trays are used as scrap metal in industrial education workshop and used for sand castings. (PS)

  13. Challenges in plastics recycling

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

    2015-01-01

    Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...

  14. Dual recycling for GEO 600

    International Nuclear Information System (INIS)

    Grote, H; Freise, A; Malec, M; Heinzel, G; Willke, B; Lueck, H; Strain, K A; Hough, J; Danzmann, K

    2004-01-01

    Dual recycling is the combination of signal recycling and power recycling; both optical techniques improve the shot-noise-limited sensitivity of interferometric gravitational-wave detectors. In addition, signal recycling can reduce the loss of light power due to imperfect interference and allows us, in principle, to beat the standard quantum limit. The interferometric gravitational-wave detector GEO 600 is the first of the kilometre-scale detectors to use signal recycling. We have recently equipped the detector with a signal-recycling mirror with a transmittance of 1%. In this paper, we present details of the detector commissioning and the first locks of the dual-recycled interferometer

  15. The Recycler Electron Cooler

    Energy Technology Data Exchange (ETDEWEB)

    Shemyakin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Prost, L. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-03-19

    The Recycler Electron cooler was the first (and so far, the only) cooler working at a relativistic energy (γ = 9.5). It was successfully developed in 1995-2004 and was in operation at Fermilab in 2005-2011, providing cooling of antiprotons in the Recycler ring. This paper describes the cooler, difficulties in achieving the required electron beam parameters and the ways to overcome them, cooling measurements, and details of operation.

  16. PET and Recycling

    Directory of Open Access Journals (Sweden)

    Funda Sevencan

    2007-08-01

    Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull. 2007; 6(4: 307-312

  17. PET and Recycling

    Directory of Open Access Journals (Sweden)

    Funda Sevencan

    2007-08-01

    Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull 2007; 6(4.000: 307-312

  18. Nuclear reactor recyclation device

    International Nuclear Information System (INIS)

    Takigawa, Yukio; Chuma, Kazuto

    1987-01-01

    Purpose: To prevent the unevenness for the coolant flow rate even when abnormality occurs to one of recycling pumps. Constitution: A plurality of jet pumps disposed at an interval around the reactor core are divided circumferentially into two sets, and a pipeway is disposed to the outside of each pair including recycling pumps corresponding to each of the sets. The pipeway is connected to the recycling inlet of the jet pump by way of a manifold. The discharge portion of the recycling pumps of the loop pipeway are connected with each other by way of communication pipes, and a normally closed valve is disposed to the communication pipe and the normally closed valve of the communication pipe is opened upon detecting abnormality for one of the recycling pumps. Thus, if either one of the pair of recycling pumps shows abnormal state, coolants flows from the other of pipeway to the outside of the loop pipeway and coolants are supplied from all the jet pumps to the reactor core portion and, accordingly, the not-uniform flow rate can be prevented to eliminate undesired effect on the reactor core. (Kamimura, M.)

  19. Recycling of Paper and Cardboard

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    waste. Recycling of paper and cardboard production waste and postconsumer waste has a long history in the pulp and paper industry. The recycled material now makes up more than half of the raw material used in European pulp and paper industry (ERPC, 2004). This chapter describes briefly how paper...... and cardboard are produced and how waste paper is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of paper recycling....

  20. Evaporative cooling: Effective latent heat of evaporation in relation to evaporation distance from the skin

    NARCIS (Netherlands)

    Havenith, G.; Bröde, P.; Hartog, E.A. den; Kuklane, K.; Holmer, I.; Rossi, R.M.; Richards, M.; Farnworth, B.; Wang, X.

    2013-01-01

    Calculation of evaporative heat loss is essential to heat balance calculations. Despite recognition that the value for latent heat of evaporation, used in these calculations, may not always reflect the real cooling benefit to the body, only limited quantitative data on this is available, which has

  1. Finite element analysis of plastic recycling machine designed for ...

    African Journals Online (AJOL)

    ... design was evaluated using finite element analysis (FEA) tool in Solid Works Computer ... Also, a minimum factor of safety value of 5.3 was obtained for shredder shaft ... Machine; Design; Recycling; Sustainability; Finite Element; Simulation ...

  2. Coal and recycling mark the way forward

    Energy Technology Data Exchange (ETDEWEB)

    Bignell, E.

    2000-11-01

    A report is given of this year's Mineral Engineering Society's annual conference held in Scarborough, UK. The themes of recycling and coal were chosen for the two days of technical presentations. Topics included the cleaning up of brown field sites; the use of recycled waste oxide to replace iron ore pellets for cooling furnaces in steel making; high pressure filtration of industrial mineral effluent; iron ore mining in Australia; screen development; the status of coal preparation technology, by RJB Mining; study of movement of material (to simulate coal) in a hopper; and a UK-Chinese project on reduction of sulphur in coal.

  3. Distributed model based control of multi unit evaporation systems

    International Nuclear Information System (INIS)

    Yudi Samyudia

    2006-01-01

    In this paper, we present a new approach to the analysis and design of distributed control systems for multi-unit plants. The approach is established after treating the effect of recycled dynamics as a gap metric uncertainty from which a distributed controller can be designed sequentially for each unit to tackle the uncertainty. We then use a single effect multi-unit evaporation system to illustrate how the proposed method is used to analyze different control strategies and to systematically achieve a better closed-loop performance using a distributed model-based controller

  4. Land-atmosphere feedbacks in EURO-CORDEX: analysis and impact on the precipitation recycling in a changing climate

    Science.gov (United States)

    Cardoso, Rita M.; Soares, Pedro M. M.; Rios, Alexandre; Trigo, Ricardo M.

    2017-04-01

    Land-atmosphere interactions are known to play a key role on climate and are expected to be critical to understand its evolution as a consequence of climate change. These land-air feedbacks are of utmost importance in those regions and periods when the intensity of evapotranspiration is high and, at the same time, controlled by soil moisture availability. In the Mediterranean Basin, the amount of rainfall coming from evapotranspiration over land represents a relevant fraction of the total precipitation in the year. Furthermore, many of these areas are affected by water limitations and are expected to be more sensitive to the impact of climate change along the upcoming decades. The latent and sensible heat fluxes in the Euro-CORDEX simulations (0.11 and 0.44) are the starting point for an assessment of the expected changes in the surface evapotranspiration and evaporative fraction (EF) in a changing climate. The changes in the heat fluxes and EF between 2071-2100 and 1971-2000 exhibit a large spread. The majority of the models forecast an increase in EF in Scandinavia and a decrease in the Mediterranean and Iberia. The WRF model, is also used to explore 3D land-atmosphere coupling over the different regions within the European CORDEX domain, at 0.44 horizontal resolution and for a high resolution domain (9km) over the Iberian Peninsula (IP). We start our analysis by computing the recycling ratio, for the hindcast (1989-2009), through the method of Eltahir and Bras, as a first approach to quantify the intensity of land-atmosphere feedbacks and their impact on the rainfall regime. This method, much more accurate than analytical Integral Moisture Budget recycling models, allows us to explore the spatial distribution of recycling over Europe and therefore focus our analysis on the most sensitive regions. The highest recycling ratio occurs in central and eastern Europe in late spring and summer; where the percentage of precipitation from evapotranspiration is higher than

  5. Effect of evaporator temperature on vapor compression refrigeration system

    Directory of Open Access Journals (Sweden)

    Abdullah A.A.A. Al-Rashed

    2011-12-01

    Full Text Available This paper presents a comparable evaluation of R600a (isobutane, R290 (propane, R134a, R22, for R410A, and R32 an optimized finned-tube evaporator, and analyzes the evaporator effect on the system coefficient of performance (COP. Results concerning the response of a refrigeration system simulation software to an increase in the amount of oil flowing with the refrigerant are presented. It is shown that there is optima of the apparent overheat value, for which either the exchanged heat or the refrigeration coefficient of performance (COP is maximized: consequently, it is not possible to optimize both the refrigeration COP and the evaporator effect. The obtained evaporator optimization results were incorporated in a conventional analysis of the vapor compression system. For a theoretical cycle analysis without accounting for evaporator effects, the COP spread for the studied refrigerants was as high as 11.7%. For cycle simulations including evaporator effects, the COP of R290 was better than that of R22 by up to 3.5%, while the remaining refrigerants performed approximately within a 2% COP band of the R22 baseline for the two condensing temperatures considered.

  6. Hydrothermal waves in evaporating sessile drops

    OpenAIRE

    Brutin, D.; Rigollet, F.; Niliot, C. Le

    2009-01-01

    Drop evaporation is a simple phenomena but still unclear concerning the mechanisms of evaporation. A common agreement of the scientific community based on experimental and numerical work evidences that most of the evaporation occurs at the triple line. However, the rate of evaporation is still empirically predicted due to the lack of knowledge on the convection cells which develop inside the drop under evaporation. The evaporation of sessile drop is more complicated than it appears due to the...

  7. Interfacial Instabilities in Evaporating Drops

    Science.gov (United States)

    Moffat, Ross; Sefiane, Khellil; Matar, Omar

    2007-11-01

    We study the effect of substrate thermal properties on the evaporation of sessile drops of various liquids. An infra-red imaging technique was used to record the interfacial temperature. This technique illustrates the non-uniformity in interfacial temperature distribution that characterises the evaporation process. Our results also demonstrate that the evaporation of methanol droplets is accompanied by the formation of wave-trains in the interfacial temperature field; similar patterns, however, were not observed in the case of water droplets. More complex patterns are observed for FC-72 refrigerant drops. The effect of substrate thermal conductivity on the structure of the complex pattern formation is also elucidated.

  8. Control of black hole evaporation?

    International Nuclear Information System (INIS)

    Ahn, Doyeol

    2007-01-01

    Contradiction between Hawking's semi-classical arguments and the string theory on the evaporation of a black hole has been one of the most intriguing problems in fundamental physics. A final-state boundary condition inside the black hole was proposed by Horowitz and Maldacena to resolve this contradiction. We point out that the original Hawking effect can also be regarded as a separate boundary condition at the event horizon for this scenario. Here, we found that the change of the Hawking boundary condition may affect the information transfer from the initial collapsing matter to the outgoing Hawking radiation during the evaporation process and as a result the evaporation process itself, significantly

  9. Comparison of fin-and-tube interlaced and face split evaporators with flow maldistribution and compensation

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl; Elmegaard, Brian; Larsen, Lars Finn Sloth

    2013-01-01

    Flow maldistribution in fin-and tube evaporators for residential air-conditioning is investigated by numerical simulation. In particular, the interlaced and the face split evaporator are compared in flow maldistribution conditions. The considered sources of maldistribution are the liquid/vapor di......Flow maldistribution in fin-and tube evaporators for residential air-conditioning is investigated by numerical simulation. In particular, the interlaced and the face split evaporator are compared in flow maldistribution conditions. The considered sources of maldistribution are the liquid...

  10. Introducing ultrasonic falling film evaporator for moderate temperature evaporation enhancement.

    Science.gov (United States)

    Dehbani, Maryam; Rahimi, Masoud

    2018-04-01

    In the present study, Ultrasonic Falling Film (USFF), as a novel technique has been proposed to increase the evaporation rate of moderate temperature liquid film. It is a proper method for some applications which cannot be performed at high temperature, such as foodstuff industry, due to their sensitivity to high temperatures. Evaporation rate of sodium chloride solution from an USFF on an inclined flat plate compared to that for Falling Film without ultrasonic irradiation (FF) at various temperatures was investigated. The results revealed that produced cavitation bubbles have different effects on evaporation rate at different temperatures. At lower temperatures, size fluctuation and collapse of bubbles and in consequence induced physical effects of cavitation bubbles resulted in more turbulency and evaporation rate enhancement. At higher temperatures, the behavior was different. Numerous created bubbles joined together and cover the plate surface, so not only decreased the ultrasound vibrations but also reduced the evaporation rate in comparison with FF. The highest evaporation rate enhancement of 353% was obtained at 40 °C at the lowest Reynolds number of 250. In addition, the results reveal that at temperature of 40 °C, USFF has the highest efficiency compared to FF. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Concrete produced with recycled aggregates

    Directory of Open Access Journals (Sweden)

    J. J. L. Tenório

    Full Text Available This paper presents the analysis of the mechanical and durable properties of recycled aggregate concrete (RAC for using in concrete. The porosity of recycled coarse aggregates is known to influence the fresh and hardened concrete properties and these properties are related to the specific mass of the recycled coarse aggregates, which directly influences the mechanical properties of the concrete. The recycled aggregates were obtained from construction and demolition wastes (CDW, which were divided into recycled sand (fine and coarse aggregates. Besides this, a recycled coarse aggregate of a specific mass with a greater density was obtained by mixing the recycled aggregates of the CDW with the recycled aggregates of concrete wastes (CW. The concrete was produced in laboratory by combining three water-cement ratios, the ratios were used in agreement with NBR 6118 for structural concretes, with each recycled coarse aggregates and recycled sand or river sand, and the reference concrete was produced with natural aggregates. It was observed that recycled aggregates can be used in concrete with properties for structural concrete. In general, the use of recycled coarse aggregate in combination with recycled sand did not provide good results; but when the less porous was used, or the recycled coarse aggregate of a specific mass with a greater density, the properties of the concrete showed better results. Some RAC reached bigger strengths than the reference concrete.

  12. Japan's fuel recycling policy

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The Atomic Energy Commission (AEC) has formulated Japanese nuclear fuel recycling plan for the next 20 years, based on the idea that the supply and demand of plutonium should be balanced mainly through the utilization of plutonium for LWRs. The plan was approved by AEC, and is to be incorporated in the 'Long term program for development and utilization of nuclear energy' up for revision next year. The report on 'Nuclear fuel recycling in Japan' by the committee is characterized by Japanese nuclear fuel recycling plan and the supply-demand situation for plutonium, the principle of the possession of plutonium not more than the demand in conformity with nuclear nonproliferation attitude, and the establishment of a domestic fabrication system of uranium-plutonium mixed oxide fuel. The total plutonium supply up to 2010 is estimated to be about 85 t, on the other hand, the demand will be 80-90 t. The treatment of plutonium is the key to the recycling and utilization of nuclear fuel. By around 2000, the private sector will commercialize the fabrication of the MOX fuel for LWRs at the annual rate of about 100 t. Commitment to nuclear nonproliferation, future nuclear fuel recycling program in Japan, MOX fuel fabrication system in Japan and so on are reported. (K.I.)

  13. Recycling of Reinforced Plastics

    Science.gov (United States)

    Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri

    2014-02-01

    This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.

  14. Recycling of reprocessed uranium

    International Nuclear Information System (INIS)

    Randl, R.P.

    1987-01-01

    Since nuclear power was first exploited in the Federal Republic of Germany, the philosophy underlying the strategy of the nuclear fuel cycle has been to make optimum use of the resource potential of recovered uranium and plutonium within a closed fuel cycle. Apart from the weighty argument of reprocessing being an important step in the treatment and disposal of radioactive wastes, permitting their optimum ecological conditioning after the reprocessing step and subsequent storage underground, another argument that, no doubt, carried weight was the possibility of reducing the demand of power plants for natural uranium. In recent years, strategies of recycling have emerged for reprocessed uranium. If that energy potential, too, is to be exploited by thermal recycling, it is appropriate to choose a slightly different method of recycling from the one for plutonium. While the first generation of reprocessed uranium fuel recycled in the reactor cuts down natural uranium requirement by some 15%, the recycling of a second generation of reprocessed, once more enriched uranium fuel helps only to save a further three per cent of natural uranium. Uranium of the second generation already carries uranium-232 isotope, causing production disturbances, and uranium-236 isotope, causing disturbances of the neutron balance in the reactor, in such amounts as to make further fabrication of uranium fuel elements inexpedient, even after mixing with natural uranium feed. (orig./UA) [de

  15. Dual manifold heat pipe evaporator

    Science.gov (United States)

    Adkins, D.R.; Rawlinson, K.S.

    1994-01-04

    An improved evaporator section is described for a dual manifold heat pipe. Both the upper and lower manifolds can have surfaces exposed to the heat source which evaporate the working fluid. The tubes in the tube bank between the manifolds have openings in their lower extensions into the lower manifold to provide for the transport of evaporated working fluid from the lower manifold into the tubes and from there on into the upper manifold and on to the condenser portion of the heat pipe. A wick structure lining the inner walls of the evaporator tubes extends into both the upper and lower manifolds. At least some of the tubes also have overflow tubes contained within them to carry condensed working fluid from the upper manifold to pass to the lower without spilling down the inside walls of the tubes. 1 figure.

  16. The evaporative vector: Homogeneous systems

    International Nuclear Information System (INIS)

    Klots, C.E.

    1987-05-01

    Molecular beams of van der Waals molecules are the subject of much current research. Among the methods used to form these beams, three-sputtering, laser ablation, and the sonic nozzle expansion of neat gases - yield what are now recognized to be ''warm clusters.'' They contain enough internal energy to undergo a number of first-order processes, in particular that of evaporation. Because of this evaporation and its attendant cooling, the properties of such clusters are time-dependent. The states of matter which can be arrived at via an evaporative vector on a typical laboratory time-scale are discussed. Topics include the (1) temperatures, (2) metastability, (3) phase transitions, (4) kinetic energies of fragmentation, and (5) the expression of magical properties, all for evaporating homogeneous clusters

  17. Recycling fusion materials

    International Nuclear Information System (INIS)

    Ooms, L.

    2005-01-01

    The inherent safety and environmental advantages of fusion power in comparison with other energy sources play an important role in the public acceptance. No waste burden for future generations is therefore one of the main arguments to decide for fusion power. The waste issue has thus been studied in several documents and the final conclusion of which it is stated that there is no permanent disposal waste needed if recycling is applied. But recycling of fusion reactor materials is far to be obvious regarding mostly the very high specific activity of the materials to be handled, the types of materials and the presence of tritium. The main objective of research performed by SCK-CEN is to study the possible ways of recycling fusion materials and analyse the challenges of the materials management from fusion reactors, based on current practices used in fission reactors and the requirements for the manufacture of fusion equipment

  18. Assessment of water droplet evaporation mechanisms on hydrophobic and superhydrophobic substrates.

    Science.gov (United States)

    Pan, Zhenhai; Dash, Susmita; Weibel, Justin A; Garimella, Suresh V

    2013-12-23

    Evaporation rates are predicted and important transport mechanisms identified for evaporation of water droplets on hydrophobic (contact angle ~110°) and superhydrophobic (contact angle ~160°) substrates. Analytical models for droplet evaporation in the literature are usually simplified to include only vapor diffusion in the gas domain, and the system is assumed to be isothermal. In the comprehensive model developed in this study, evaporative cooling of the interface is accounted for, and vapor concentration is coupled to local temperature at the interface. Conjugate heat and mass transfer are solved in the solid substrate, liquid droplet, and surrounding gas. Buoyancy-driven convective flows in the droplet and vapor domains are also simulated. The influences of evaporative cooling and convection on the evaporation characteristics are determined quantitatively. The liquid-vapor interface temperature drop induced by evaporative cooling suppresses evaporation, while gas-phase natural convection acts to enhance evaporation. While the effects of these competing transport mechanisms are observed to counterbalance for evaporation on a hydrophobic surface, the stronger influence of evaporative cooling on a superhydrophobic surface accounts for an overprediction of experimental evaporation rates by ~20% with vapor diffusion-based models. The local evaporation fluxes along the liquid-vapor interface for both hydrophobic and superhydrophobic substrates are investigated. The highest local evaporation flux occurs at the three-phase contact line region due to proximity to the higher temperature substrate, rather than at the relatively colder droplet top; vapor diffusion-based models predict the opposite. The numerically calculated evaporation rates agree with experimental results to within 2% for superhydrophobic substrates and 3% for hydrophobic substrates. The large deviations between past analytical models and the experimental data are therefore reconciled with the

  19. Integrated Nuclear Recycle Plant

    International Nuclear Information System (INIS)

    Patodi, Anuj; Parashar, Abhishek; Samadhiya, Akshay K.; Ray, Saheli; Dey, Mitun; Singh, K.K.

    2017-01-01

    Nuclear Recycle Board (NRB), Tarapur proposes to set up an 'Integrated Nuclear Recycle Plant' at Tarapur. This will be located in the premises of BARC facilities. The project location is at coastal town of Tarapur, 130 Km north of Mumbai. Project area cover of INRP is around 80 hectares. The plant will be designed to process spent fuel received from Pressurized Heavy Water Reactors (PHWRs). This is the first large scale integrated plant of the country. INRP will process spent fuel obtained from indigenous nuclear power plants and perform left over nuclear waste disposal

  20. Mox fuels recycling

    International Nuclear Information System (INIS)

    Gay, A.

    1998-01-01

    This paper will firstly emphasis that the first recycling of plutonium is already an industrial reality in France thanks to the high degree of performance of La Hague and MELOX COGEMA's plants. Secondly, recycling of spent Mixed OXide fuel, as a complete MOX fuel cycle, will be demonstrated through the ability of the existing plants and services which have been designed to proceed with such fuels. Each step of the MOX fuel cycle concept will be presented: transportation, reception and storage at La Hague and steps of spent MOX fuel reprocessing. (author)

  1. Numerical study of the evaporation process and parameter estimation analysis of an evaporation experiment

    Directory of Open Access Journals (Sweden)

    K. Schneider-Zapp

    2010-05-01

    Full Text Available Evaporation is an important process in soil-atmosphere interaction. The determination of hydraulic properties is one of the crucial parts in the simulation of water transport in porous media. Schneider et al. (2006 developed a new evaporation method to improve the estimation of hydraulic properties in the dry range. In this study we used numerical simulations of the experiment to study the physical dynamics in more detail, to optimise the boundary conditions and to choose the optimal combination of measurements. The physical analysis exposed, in accordance to experimental findings in the literature, two different evaporation regimes: (i a soil-atmosphere boundary layer dominated regime (regime I close to saturation and (ii a hydraulically dominated regime (regime II. During this second regime a drying front (interface between unsaturated and dry zone with very steep gradients forms which penetrates deeper into the soil as time passes. The sensitivity analysis showed that the result is especially sensitive at the transition between the two regimes. By changing the boundary conditions it is possible to force the system to switch between the two regimes, e.g. from II back to I. Based on this findings a multistep experiment was developed. The response surfaces for all parameter combinations are flat and have a unique, localised minimum. Best parameter estimates are obtained if the evaporation flux and a potential measurement in 2 cm depth are used as target variables. Parameter estimation from simulated experiments with realistic measurement errors with a two-stage Monte-Carlo Levenberg-Marquardt procedure and manual rejection of obvious misfits lead to acceptable results for three different soil textures.

  2. Fermilab Recycler Collimation System Design

    Energy Technology Data Exchange (ETDEWEB)

    Brown, B. C. [Fermilab; Adamson, P. [Fermilab; Ainsworth, R. [Fermilab; Capista, D. [Fermilab; Hazelwood, K. [Fermilab; Kourbanis, I. [Fermilab; Mokhov, N. V. [Fermilab; Morris, D. K. [Fermilab; Murphy, M. [Fermilab; Sidorov, V. [Fermilab; Stern, E. [Fermilab; Tropin, I. [Fermilab; Yang, M-J. [Fermilab

    2016-10-04

    To provide 700 kW proton beams for neutrino production in the NuMI facility, we employ slip stacking in the Recycler with transfer to the Main Injector for recapture and acceleration. Slip stacking with 12 Booster batches per 1.33 sec cycle of the Main Injector has been implemented and briefly tested while extensive operation with 8 batches and 10 batches per MI cycle has been demonstrated. Operation in this mode since 2013 shows that loss localization is an essential component for long term operation. Beam loss in the Recycler will be localized in a collimation region with design capability for absorbing up to 2 kW of lost protons in a pair of 20-Ton collimators (absorbers). This system will employ a two stage collimation with a thin molybdenum scattering foil to define the bottom edge of both the injected and decelerated-for-slipping beams. Optimization and engineering design of the collimator components and radiation shielding are based on comprehensive MARS15 simulations predicting high collimation efficiency as well as tolerable levels of prompt and residual radiation. The system installation during the Fermilab 2016 facility shutdown will permit commissioning in the subsequent operating period.

  3. Viscoelastic behaviour of cold recycled asphalt mixes

    Science.gov (United States)

    Cizkova, Zuzana; Suda, Jan

    2017-09-01

    Behaviour of cold recycled mixes depends strongly on both the bituminous binder content (bituminous emulsion or foamed bitumen) and the hydraulic binder content (usually cement). In the case of cold recycled mixes rich in bitumen and with low hydraulic binder content, behaviour is close to the viscoelastic behaviour of traditional hot mix asphalt. With decreasing bituminous binder content together with increasing hydraulic binder content, mixes are characteristic with brittle behaviour, typical for concrete pavements or hydraulically bound layers. The behaviour of cold recycled mixes with low content of both types of binders is similar to behaviour of unbound materials. This paper is dedicated to analysing of the viscoelastic behaviour of the cold recycled mixes. Therefore, the tested mixes contained higher amount of the bituminous binder (both foamed bitumen and bituminous emulsion). The best way to characterize any viscoelastic material in a wide range of temperatures and frequencies is through the master curves. This paper includes interesting findings concerning the dependency of both parts of the complex modulus (elastic and viscous) on the testing frequency (which simulates the speed of heavy traffic passing) and on the testing temperature (which simulates the changing climate conditions a real pavement is subjected to).

  4. Characteristics of a micro-fin evaporator: Theoretical analysis and experimental verification

    OpenAIRE

    Zheng Hui-Fan; Fan Xiao-Wei; Wang Fang; Liang Yao-Hua

    2013-01-01

    A theoretical analysis and experimental verification on the characteristics of a micro-fin evaporator using R290 and R717 as refrigerants were carried out. The heat capacity and heat transfer coefficient of the micro-fin evaporator were investigated under different water mass flow rate, different refrigerant mass flow rate, and different inner tube diameter of micro-fin evaporator. The simulation results of the heat transfer coefficient are fairly in good a...

  5. Filter Backwash Recycling Rule Documents

    Science.gov (United States)

    The purpose of the FBRR is to require (PWSs) to review their recycle practices and, where appropriate, work with the state Primacy Agency to make any necessary changes to recycle practices that may compromise microbial control.

  6. Overview of HTGR fuel recycle

    International Nuclear Information System (INIS)

    Notz, K.J.

    1976-01-01

    An overview of HTGR fuel recycle is presented, with emphasis placed on reprocessing and fuel kernel refabrication. Overall recycle operations include (1) shipment and storage, (2) reprocessing, (3) refabrication, (4) waste handling, and (5) accountability and safeguards

  7. Lake Nasser evaporation reduction study

    Directory of Open Access Journals (Sweden)

    Hala M.I. Ebaid

    2010-10-01

    Full Text Available This study aims to evaluate the reduction of evaporation of Lake Nasser’s water caused by disconnecting (fully or partially some of its secondary channels (khors. This evaluation integrates remote sensing, Geographic Information System (GIS techniques, aerodynamic principles, and Landsat7 ETM+ images. Three main procedures were carried out in this study; the first derived the surface temperature from Landsat thermal band; the second derived evaporation depth and approximate evaporation volume for the entire lake, and quantified evaporation loss to the secondary channels’ level over one month (March by applied aerodynamic principles on surface temperature of the raster data; the third procedure applied GIS suitability analysis to determine which of these secondary channels (khors should be disconnected. The results showed evaporation depth ranging from 2.73 mm/day at the middle of the lake to 9.58 mm/day at the edge. The evaporated water-loss value throughout the entire lake was about 0.86 billion m3/month (March. The analysis suggests that it is possible to save an approximate total evaporation volume loss of 19.7 million m3/month (March, and thus 2.4 billion m3/year, by disconnecting two khors with approximate construction heights of 8 m and 15 m. In conclusion, remote sensing and GIS are useful for applications in remote locations where field-based information is not readily available and thus recommended for decision makers remotely planning in water conservation and management.

  8. Evaporative gas turbine cycles. A thermodynamic evaluation of their potential

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, P M

    1993-03-01

    The report presents a systematic method of thermodynamically evaluating different gas turbine cycles, treating the working fluids as ideal gases (c{sub p}=c{sub p}(T)). All models used to simulate different components in the cycles are presented in the report in detail and then connected in a computer program fully developed by the author. The report focuses on the theme of evaporative gas turbine cycles, in which low level heat is used to evaporate water into the compressed air stream between the compressor and recuperator. This leads to efficiency levels close to a comparable combined cycle but without the steam bottoming cycle. A parametric analysis has been conducted with the aim of deciding the best configuration of an evaporative cycle both for an uncooled expander and for a cooled expander. The model proposed to simulate the cooled expander is a combination between two existing models. (121 refs., 35 figs.,).

  9. Negative pressure characteristics of an evaporating meniscus at nanoscale

    Directory of Open Access Journals (Sweden)

    Maroo Shalabh

    2011-01-01

    Full Text Available Abstract This study aims at understanding the characteristics of negative liquid pressures at the nanoscale using molecular dynamics simulation. A nano-meniscus is formed by placing liquid argon on a platinum wall between two nano-channels filled with the same liquid. Evaporation is simulated in the meniscus by increasing the temperature of the platinum wall for two different cases. Non-evaporating films are obtained at the center of the meniscus. The liquid film in the non-evaporating and adjacent regions is found to be under high absolute negative pressures. Cavitation cannot occur in these regions as the capillary height is smaller than the critical cavitation radius. Factors which determine the critical film thickness for rupture are discussed. Thus, high negative liquid pressures can be stable at the nanoscale, and utilized to create passive pumping devices as well as significantly enhance heat transfer rates.

  10. Recycling - Danish Waste Management Strategy

    DEFF Research Database (Denmark)

    Romann, Anne Funch; Thøgersen, John; Husmer, Lis

    The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials.......The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials....

  11. Vehicle recycling regulations

    DEFF Research Database (Denmark)

    Smink, Carla

    2007-01-01

    The number of end-of-life vehicles (ELVs) in the EU is increasing continously. Around 75 percent of an ELV are recyclable metals. The forecast growth in the number of ELVs calls for regulation that aims to minimise the environmental impact of a car. Using Denmark as an example, this article...

  12. Nuclear fuel recycling system

    International Nuclear Information System (INIS)

    Lee, H.R.; Koch, A.K.; Krawczyk, A.

    1981-01-01

    A process is provided for recycling sintered uranium dioxide fuel pellets rejected during fuel manufacture and the swarf from pellet grinding. The scrap material is prepared mechanically by crushing and milling as a high solids content slurry, using scrap sintered UO 2 pellets as the grinding medium under an inert atmosophere

  13. Recycling as moral behaviour

    DEFF Research Database (Denmark)

    Thøgersen, John

    It is argued in this paper that in the affluent, industrial societies, environmental behaviours like recycling are typically classified within ""the domain of morality"" in people's minds. Intentions regarding these types of behaviours are not ba a thorough - conscious or unconscious - calculation...

  14. Recycling Behavior: A Multidimensional Approach

    Science.gov (United States)

    Meneses, Gonzalo Diaz; Palacio, Asuncion Beerli

    2005-01-01

    This work centers on the study of consumer recycling roles to examine the sociodemographic and psychographic profile of the distribution of recycling tasks and roles within the household. With this aim in mind, an empirical work was carried out, the results of which suggest that recycling behavior is multidimensional and comprises the undertaking…

  15. The use of reverse osmosis at nuclear power plants. Replacement of evaporator

    International Nuclear Information System (INIS)

    Kus, Pavel; Bartova, Sarka; Kunesova, Katerina; Smejdova, Vladena; Vonkova, Katerina

    2015-01-01

    Evaporators are being used in nuclear power plants for the treatment of primary coolant containing H3BO3 for neutron absorption and other components for adjusting water chemistry. The aim is to achieve a concentrated H3BO3 solution, which is further purified by ion exchangers and then recycled into the primary cycle. Operation of evaporators is expensive, therefore reverse osmosis was proposed as one promising alternative. A pilot-plant RO unit was used for the experiments performed with feed solution. The successful technology is now being implemented at Temelin NPP.

  16. The use of reverse osmosis at nuclear power plants. Replacement of evaporator

    Energy Technology Data Exchange (ETDEWEB)

    Kus, Pavel; Bartova, Sarka; Kunesova, Katerina; Smejdova, Vladena; Vonkova, Katerina [Research Centre Rez, Husinec-Rez (Czech Republic). Technological Circuits

    2015-06-01

    Evaporators are being used in nuclear power plants for the treatment of primary coolant containing H3BO3 for neutron absorption and other components for adjusting water chemistry. The aim is to achieve a concentrated H3BO3 solution, which is further purified by ion exchangers and then recycled into the primary cycle. Operation of evaporators is expensive, therefore reverse osmosis was proposed as one promising alternative. A pilot-plant RO unit was used for the experiments performed with feed solution. The successful technology is now being implemented at Temelin NPP.

  17. Quantifying recycled moisture fraction in precipitation of an arid region using deuterium excess

    Directory of Open Access Journals (Sweden)

    Yanlong Kong

    2013-01-01

    Full Text Available Terrestrial moisture recycling by evapotranspiration has recently been recognised as an important source of precipitation that can be characterised by its isotopic composition. Up to now, this isotope technique has mainly been applied to moisture recycling in some humid regions, including Brazil, Great Lakes in North America and the European Alps. In arid and semi-arid regions, the contribution of transpiration by plants to local moisture recycling can be small, so that evaporation by bare soil and surface water bodies dominates. Recognising that the deuterium excess (d-excess of evaporated moisture is significantly different from that of the original water, we made an attempt to use this isotopic parameter for estimating moisture recycling in the semi-arid region of Eastern Tianshan, China. We measured the d-excess of samples taken from individual precipitation events during a hydrological year from 2003 to 2004 at two Tianshan mountain stations, and we used long-term monthly average values of the d-excess for the station Urumqi, which are available from the International Atomic Energy Agency–World Meteorological Organization (IAEA–WMO Global Network of Isotopes in Precipitation (GNIP. Since apart from recycling of moisture from the ground, sub-cloud evaporation of falling raindrops also affects the d-excess of precipitation, the measured values had to be corrected for this evaporation effect. For the selected stations, the sub-cloud evaporation was found to change between 0.1 and 3.8%, and the d-excess decreased linearly with increasing sub-cloud evaporation at about 1.1‰ per 1% change of sub-cloud evaporation. Assuming simple mixing between advected and recycled moisture, the recycled fraction in precipitation has been estimated to be less than 2.0±0.6% for the Tianshan mountain stations and reach values up to 15.0±0.7% in the Urumqi region. The article includes a discussion of these findings in the context of water cycling in the

  18. Theoretical and testing performance of an innovative indirect evaporative chiller

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yi; Xie, Xiaoyun [Department of Building Science and Technology, Tsinghua University, Beijing (China)

    2010-12-15

    An indirect evaporative chiller is a device used to produce chilled water at a temperature between the wet bulb temperature and dew point of the outdoor air, which can be used in building HVAC systems. This article presents a theoretical analysis and practical performance of an innovative indirect evaporative chiller. First, the process of the indirect evaporative chiller is introduced; then, the matching characteristics of the process are presented and analyzed. It can be shown that the process that produces cold water by using dry air is a nearly-reversible process, so the ideal produced chilled water temperature of the indirect evaporative chiller can be set close to the dew point temperature of the chiller's inlet air. After the indirect evaporative chiller was designed, simulations were done to analyze the output water temperature, the cooling efficiency relative to the inlet dew point temperature, and the COP that the chiller can performance. The first installation of the indirect evaporative chiller of this kind has been run for 5 years in a building in the city of Shihezi. The tested output water temperature of the chiller is around 14-20 C, which is just in between of the outdoor wet bulb temperature and dew point. The tested COP{sub r,s} of the developed indirect evaporative chiller reaches 9.1. Compared with ordinary air conditioning systems, the indirect evaporative chiller can save more than 40% in energy consumption due to the fact that the only energy consumed is from pumps and fans. An added bonus is that the indirect evaporative chiller uses no CFCs that pollute to the aerosphere. The tested internal parameters, such as the water-air flow rate ratio and heat transfer area for each heat transfer process inside the chiller, were analyzed and compared with designed values. The tested indoor air conditions, with a room temperature of 23-27 C and relative humidity of 50-70%, proved that the developed practical indirect evaporative chiller

  19. Evaporative cycles - in theory and in practise

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, P.M.

    2000-08-01

    The thesis is based on applied research, rather closed to industrial development. The developed simulation model, for pre-design of evaporative gas turbine cycles, has been validated in a 600 kW pilot plant and in rebuilt turbo-charged diesel engines. Besides of the work with the thesis including theoretical modelling and hardware development concerning wet cycles, the work has also resulted in three patents dealing with the technique studied. The main feature of the evaporative cycles is the way the integration between the gas and liquid flows is executed, combined with using low-level heat gathered into the liquid phase which is later used to evaporate the liquid itself in a humidification tower. In this tower, the mass- and heat transfer take place under stable physical laws, and if the tower is properly designed, the distilling effect in the tower will also be high. Today the combined cycle has the best thermal efficiency to generate electricity from fuels. Every new power cycle, including the evaporative cycles, will therefore be compared with power stations based on combined cycles. In evaporative cycles, the steam bottoming cycle of the combined cycles has been eliminated. Instead the 'steam' cycle is integrated into the gas cycle. This action has a favourable effect on thermal efficiency and on NO{sub x} formation in the combustion zone. The major part of this thesis is about the EvGT-project. At Lund University, the major objective of this project was to develop, design, erect and operate the world's first evaporative gas turbine unit. The objective was accomplished in 1999, and in the process of reaching the objective, rather large modelling errors, both thermodynamic and dimensioning of the humidification tower, have been detected in the open literature. It seems as if the pressure dependency of the humidification process has been underestimated in the models used today. The EvGT-pilot plant at Lund University was built and taken into

  20. The Fernald Waste Recycling Program

    International Nuclear Information System (INIS)

    Motl, G.P.

    1993-01-01

    Recycling is considered a critical component of the waste disposition strategy at the Fernald Plant. It is estimated that 33 million cubic feet of waste will be generated during the Fernald cleanup. Recycling some portion of this waste will not only conserve natural resources and disposal volume but will, even more significantly, support the preservation of existing disposition options such as off-site disposal or on-site storage. Recognizing the strategic implications of recycling, this paper outlines the criteria used at Fernald to make recycle decisions and highlights several of Fernald's current recycling initiatives

  1. Flow within an evaporating glycerol-water binary droplet: Segregation by gravitational effects

    Science.gov (United States)

    Li, Yaxing; Lv, Pengyu; Diddens, Christian; Wijshoff, Herman; Versluis, Michel; Lohse, Detlef

    2017-11-01

    The flow within an evaporating glycerol-water binary droplet with Bond number Bo PIV for both sessile and pendant droplets during evaporation process, which surprisingly show opposite radial flow directions - inward and outward, respectively. This observation clearly reveals that gravitational effects play a crucial role in controlling flow fields within the evaporating droplets. We theoretically analyse that this gravity-driven effect is caused by density gradients due to the local concentration difference of glycerol within the droplet triggered by different volatilities of the two components during evaporation. Finally, for confirmation, we numerically simulate the process, revealing a good agreement with experimental results.

  2. Multiple recycling of NdFeB-type sintered magnets

    Energy Technology Data Exchange (ETDEWEB)

    Zakotnik, M. [Department of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)], E-mail: miha.zakotnik@gmail.com; Harris, I.R.; Williams, A.J. [Department of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2009-02-05

    Some fully dense, sintered NdFeB-type magnets (employed in VCM disc drives) have been subjected to a recycling process using the hydrogen decrepitation (HD) process. After a brief milling treatment, the powder was aligned, pressed and re-sintered and this procedure was repeated four times with a progressive fall in the density and in the magnetic properties. The chemical analysis indicated that this was due to the progressive oxidation of the Nd-rich material and to some Nd loss by evaporation. The procedure was then repeated but with the addition (blending) of a fine powder of neodymium hydride after the first cycle. It was found that the addition of 1 at.% of neodymium at each stage was sufficient to maintain the density and the magnetic properties of the recycled magnets up to and including the 4th cycle. Inductively coupled plasma (ICP) and metallographic analysis indicated that the neodymium hydride additions compensated for the neodymium loss due to evaporation and to oxidation so that the proportion of Nd-rich material remained approximately constant. The additional amount of Nd{sub 2}O{sub 3} in the blended recycled magnets appeared to inhibit grain growth on the 3rd and 4th cycles when compared to that of the unblended magnets. The next challenge is to see if the process can be scaled-up to an industrial scale.

  3. Recycling phosphorus from wastewater

    DEFF Research Database (Denmark)

    Lemming, Camilla Kjærulff

    wastewater-derived products, and to relate this to the availability from other P-containing waste products and mineral P fertiliser. This included aspects of development over time and soil accumulation, as well as effects of soil pH and the spatial distribution in soil. The P sources applied in this PhD work...... reserves. Wastewater represents the largest urban flow of P in waste. Hence, knowledge about plant P availability of products from the wastewater treatment system, and also comparison to other waste P sources and mineral P is essential to obtain an efficient recycling and to prioritise between different P...... recycling options. The work of this PhD focused on the plant P availability of sewage sludge, a P-rich residue from wastewater treatment which is commonly applied to agricultural soil in Denmark. The overall objective of the PhD work was to evaluate the plant availability of P in sewage sludge and other...

  4. Thermal management optimization of a thermoelectric-integrated methanol evaporator using a compact CFD modeling approach

    DEFF Research Database (Denmark)

    Xin, Gao; Chen, Min; Snyder, G. Jeffrey

    2013-01-01

    exchange structure. The structure transfers the fuel cell exhaust heat to the evaporation chamber to evaporate the methanol, where TE modules are installed in between to facilitate the heat regulation. In this work, firstly, a numerical study is conducted to determine the working currents and working modes......To better manage the magnitude and the direction of the heat flux in an exchanger-based methanol evaporator of a fuel cell system, thermoelectric (TE) modules can be deployed as TE heat flux regulators (TERs). The performance of the TE-integrated evaporator is strongly influenced by its heat......, and uses a different material property acquisition method based on module manufacturers’ datasheets. Secondly, a simulation study is carried out on the novel evaporator to minimize its thermal resistance and to assess the evaporator pressure drop. The factors studied include: type of the fins of the heat...

  5. Numerical study of evaporators in power plants for improved dynamic fl exibility

    DEFF Research Database (Denmark)

    Johansen, Axel Vodder Ohrt

    The main objective of this Ph.D. thesis is to describe and analyse the most recent knowledge about operational flexibility in steam power plant evaporators, based on mathematical / numerical methods. The thesis addresses a mathematical study of steam power plant evaporators and involves the reader...... will be introduced to basic concepts in the power sector, including lifetime terms, such as corrosion, creep and fatigue, related to the evaporator tubes, which are responsible for the transfer of energy from the boiler to the water / steam circuit of a power plant. New evaporator technologies are briefly described......, followed by a simulation of a steam power plant evaporator of Skærbækværket (SKV3), which is one of DONG Energy’s ten central CHP plants, built in 1998 and located in Skærbæk at the mouth of Kolding Fjord in Denmark. Here different heating profiles of the evaporator are investigated, as well...

  6. Effect of evaporation on the growth kinetics in a model for two species

    International Nuclear Information System (INIS)

    El-Nashar, Hassan F.

    2002-02-01

    A surface growth model for two species is proposed, when deposition, surface diffusion and evaporation are considered, in (1+1)-dimensions. A Monte Carlo simulation is carried out, focusing on the effect of evaporation on the evolution of the amount of roughness. The results show that the interplay between deposition, surface diffusion and evaporation slows down the rate of growth of the surface width. In addition, when the rate of evaporation increases, the surface width grows faster to a higher value, in comparison to the case of low rate of evaporation. This introduces changes in the scaling exponents which show that evaporation should be given equal or as much consideration as deposition and surface relaxation. (author)

  7. Usage of Recycled Pet

    OpenAIRE

    Tayyar, A. Ebru; Üstün, Sevcan

    2010-01-01

    The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PE...

  8. Plutonium recycling in PWR

    International Nuclear Information System (INIS)

    Youinou, G.; Girieud, R.; Guigon, B.

    2000-01-01

    Two concepts of 100% MOX PWR cores are presented. They are designed such as to minimize the consequences of the introduction of Pu on the core control. The first one has a high moderation ratio and the second one utilizes an enriched uranium support. The important design parameters as well as their capabilities to multi recycle Pu are discussed. We conclude with the potential interest of the two concepts. (author)

  9. COPPER CABLE RECYCLING TECHNOLOGY

    International Nuclear Information System (INIS)

    Chelsea Hubbard

    2001-01-01

    The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D and D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D and D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness

  10. Recycling of merchant ships

    Directory of Open Access Journals (Sweden)

    Magdalena Klopott

    2013-12-01

    Full Text Available The article briefly outlines the issues concerning ship recycling. It highlights ships' high value as sources of steel scrap and non-ferrous metals, without omitting the fact that they also contain a range of hazardous substances. Moreover, the article also focuses on basic ship demolition methods and their environmental impact, as well as emphasizes the importance of “design for ship recycling” philosophy.

  11. Evaporation and condensation at a liquid surface. II. Methanol

    Science.gov (United States)

    Matsumoto, Mitsuhiro; Yasuoka, Kenji; Kataoka, Yosuke

    1994-11-01

    The rates of evaporation and condensation of methanol under the vapor-liquid equilibrium condition at the temperature of 300 and 350 K are investigated with a molecular dynamics computer simulation. Compared with the argon system (reported in part I), the ratio of self-reflection is similar (˜10%), but the ratio of molecule exchange is several times larger than the argon, which suggests that the conventional assumption of condensation as a unimolecular process completely fails for associating fluids. The resulting total condensation coefficient is 20%-25%, and has a quantitative agreement with a recent experiment. The temperature dependence of the evaporation-condensation behavior is not significant.

  12. Distribution of Evaporating CO2 in Parallel Microchannels

    DEFF Research Database (Denmark)

    Brix, Wiebke; Elmegaard, Brian

    2008-01-01

    The impact on the heat exchanger performance due to maldistribution of evaporating CO2 in parallel channels is investigated numerically. A 1D steady state simulation model of a microchannel evaporator is built using correlations from the literature to calculate frictional pressure drop and heat...... transfer coefficients. For two channels in parallel two different cases of maldistribution are studied. Firstly, the impact of a non-uniform air flow is considered, and secondly the impact of maldistribution of the two phases in the inlet manifold is investigated. The results for both cases are compared...

  13. Recycling and Networking

    Directory of Open Access Journals (Sweden)

    T. Bányai

    2004-01-01

    Full Text Available In recent years, the notion that for environmental and legislative reasons improvements The national environmental policies and practice, including recycling strategies, are desirable and in many cases might be economically beneficial has been gaining ground. Although according to recent surveys the state of the environment in Hungary is in line with average values of the European Union, the main challenge for the country is to achieve sustainability in economic, environmental and technological terms. With a view to accession to the European Union, a harmonisation strategy must be worked out and implemented. This harmonisation strategy includes not only legislative aspects, but also social, technological, financial and logistic considerations.Because of the high logistic costs of achieving closed loop recycling systems, the author focuses on logistic aspects and tasks of the improvement phases and concentrates on the possibilities of networking and co-operation. The paper describes some possible alternative solutions for co-operative recycling processes, to improve the following logistic parameters: delivery times, accuracy of supply, running times, utilization of capacities, stock quantities, flexibility, transparency of the system, high forwarding capability, quality of product. The logistic aspects of co-operation will be analysed from the viewpoint of a closed loop economy.

  14. Economics and recycling

    Energy Technology Data Exchange (ETDEWEB)

    Butlin, J A

    1977-06-01

    The current state of recycling technology could appear to be a question of supply and demand, first for storage, disposal, and reclamation facilities, and secondly, for reclaimed materials. If supply and demand are to be relied upon as an environmental policy tool, several conditions need to exist within the economy: supply data for storage and disposal facilities should reflect the full social cost of their use for this purpose relative to any other; demand data for the use of storage facilities must reflect the full social benefit of having waste go through one channel rather than some other; demand for and supply of reclaimed materials for recycling must reflect the full costs and benefits of rechanneling them back into production or consumption; and the markets for products competitive to recycled raw materials (mainly virgin raw materials) should reflect full social costs and benefits, as should the markets for the alternative uses of storage and disposal facilities. If these conditions are met (in addition to a few technical ones), then the problem of waste management will not arise. (MCW)

  15. Recycling of packing plastics

    International Nuclear Information System (INIS)

    Gintenreiter-Koegl, S.

    2001-05-01

    The ordinance on the avoidance of packaging waste was a serious intervention in the public and private waste management in Austria. Above all the high expenses for an overall packaging waste collection and the recycling of packaging plastics were criticized. The landfill ordinance comes into force in 2004 and this means another major change in the Austrian waste management system. In the course of this change the overall collection and the recycling and recovery of waste streams, especially of the high caloric plastics waste, have to be discussed again. The goal of this work was on the one hand to develop and adapt the hydrocracking process for the recovery of mixed plastics waste and to show a possible application in Austria. On the other hand the work shows the technical, ecological and economical conditions for packaging plastics recycling and recovery in order to find optimum applications for the processes and to examine their contribution to a sustainable development. A hydrocracking test plant for the processing of mixed plastic wastes was built and had been running for about three years. The tests were carried out successfully and the suitability of the technology for the recovery of packaging plastics could be shown. Results show at least a 35 % yield of fuel. The hydrocracking technology is quite common in the oil industries and therefore an integration on a refinery site is suggested. (author)

  16. Recycling retention functions

    International Nuclear Information System (INIS)

    Skrable, K.W.; Chabot, G.E.; Johnson, M.H.

    1981-01-01

    Beginning with the concept of any number of physiologically meaningful compartments that recycle material with a central extracellular fluid compartment and considering various excretion pathways, we solve the differential equations describing the kinetics by the method of Laplace to obtain concise algebraic expressions for the retentions. These expressions contain both fundamental and eigenvalue rate constants; the eigenvalue rate constants are obtained from the solution of a polynomial incorporating the fundamental rate constants. Mathematically exact expressions that predict the biodistribution resulting from continuous uptakes are used to obtain very simple mathematically exact steady state expressions as well as approximate expressions applicable to any time. These steady state and approximate expressions contain only the fundamental rate constants; also, they include a recycling factor that describes the increase in the biodistributions because of recycling. To obtain the values of the fundamental rate constants, short term kinetics studies along with data on the long term distributions are suggested. Retention functions obtained in this way predict both the short term and long term distributions; they therefore are useful in the interpretation of bioassay data and in the estimation of internal doses

  17. The sustainability of LNG evaporation

    NARCIS (Netherlands)

    Stougie, L.; Van der Kooi, H.J.

    2011-01-01

    Numerous LNG (Liquefied Natural Gas) import terminals are under construction to fulfil the growing demand for energy carriers. After storage in tanks, the LNG needs to be heated and evaporated, also called ‘regasified’, to the natural gas needed in households and industry. Several options exist for

  18. Evaporation in relation to hydrology

    NARCIS (Netherlands)

    Wartena, L.; Keijman, J.Q.; Bruijn, H.A.R. de; Bakel, P.J.T. van; Stricker, J.N.M.; Velds, C.A.

    1981-01-01

    In meteorology some topics enjoy particular interest from other disciplines. The interest of hydrologists for the evaporation of water is a case in point, understandably and rightly so. In fact, over the last few decades, hydrology has clearly done more than using meteorological knowledge thus

  19. Micro-evaporation electrolyte concentrator

    NARCIS (Netherlands)

    Timmer, B.H.; van Delft, K.M.; Olthuis, Wouter; Bergveld, Piet; van den Berg, Albert

    2003-01-01

    The sensitivity of miniaturized chemical analysis systems depends most of the time on the obtainable detection limit. Concentrating the analyte prior to the detection system can enhance the detection limit. In this writing an analyte concentrator is presented that makes use of evaporation to

  20. Optimum operating conditions for a water purification process integrated to a heat transformer with energy recycling using neural network inverse

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, J.A.; Siqueiros, J.; Juarez-Romero, D. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas, Universidad Autonoma del Estado de Morelos (UAEM), Av. Universidad No. 1001, Col. Chamilpa, Cuernavaca, Morelos C.P. 62209 (Mexico); Bassam, A. [Posgrado en Ingenieria y Ciencias Aplicadas, Universidad Autonoma del Estado de Morelos (UAEM), Av. Universidad No. 1001, Col. Chamilpa, Cuernavaca, Morelos C.P. 62209 (Mexico)

    2009-04-15

    Artificial neural network inverse (ANNi) is applied to calculate the optimal operating conditions on the coefficient of performance (COP) for a water purification process integrated to an absorption heat transformer with energy recycling. An artificial neural network (ANN) model is developed to predict the COP which was increased with energy recycling. This ANN model takes into account the input and output temperatures for each one of the four components (absorber, generator, evaporator, and condenser), as well as two pressures and LiBr + H{sub 2}O concentrations. For the network, a feedforward with one hidden layer, a Levenberg-Marquardt learning algorithm, a hyperbolic tangent sigmoid transfer function and a linear transfer function were used. The best fitting training data set was obtained with three neurons in the hidden layer. On the validation data set, simulations and experimental data test were in good agreement (R > 0.99). This ANN model can be used to predict the COP when the input variables (operating conditions) are well known. However, to control the COP in the system, we developed a strategy to estimate the optimal input variables when a COP is required from ANNi. An optimization method (the Nelder-Mead simplex method) is used to fit the unknown input variable resulted from the ANNi. This methodology can be applied to control on-line the performance of the system. (author)

  1. Numerical study of a novel dew point evaporative cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Riangvilaikul, B.; Kumar, S. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120 (Thailand)

    2010-11-15

    Dew point evaporative cooling system is an alternative to vapor compression air conditioning system for sensible cooling of ventilation air. This paper presents the theoretical performance of a novel dew point evaporative cooling system operating under various inlet air conditions (covering dry, moderate and humid climate) and influence of major operating parameters (namely, velocity, system dimension and the ratio of working air to intake air). A model of the dew point evaporative cooling system has been developed to simulate the heat and mass transfer processes. The outlet air conditions and system effectiveness predicted by the model using numerical method for known inlet parameters have been validated with experimental findings and with recent literature. The model was used to optimize the system parameters and to investigate the system effectiveness operating under various inlet air conditions. (author)

  2. Theoretical and computational analyses of LNG evaporator

    Science.gov (United States)

    Chidambaram, Palani Kumar; Jo, Yang Myung; Kim, Heuy Dong

    2017-04-01

    Theoretical and numerical analysis on the fluid flow and heat transfer inside a LNG evaporator is conducted in this work. Methane is used instead of LNG as the operating fluid. This is because; methane constitutes over 80% of natural gas. The analytical calculations are performed using simple mass and energy balance equations. The analytical calculations are made to assess the pressure and temperature variations in the steam tube. Multiphase numerical simulations are performed by solving the governing equations (basic flow equations of continuity, momentum and energy equations) in a portion of the evaporator domain consisting of a single steam pipe. The flow equations are solved along with equations of species transport. Multiphase modeling is incorporated using VOF method. Liquid methane is the primary phase. It vaporizes into the secondary phase gaseous methane. Steam is another secondary phase which flows through the heating coils. Turbulence is modeled by a two equation turbulence model. Both the theoretical and numerical predictions are seen to match well with each other. Further parametric studies are planned based on the current research.

  3. OLI/ESP Modeling Of The Semi-Integrated Pilot Plant For Estimate Of Campaigns I-IV Simulant Volumes

    International Nuclear Information System (INIS)

    CARL, BARNES

    2004-01-01

    Four SIPP campaigns have been planned to investigate the effect of recycle streams on the RPP-WTP pretreatment process such as the filter flux rate and other areas of interest. This document describes OLI/ESP modeling work done in support of the planning and operation of the SIPP. An existing OLI/ESP steady-state model was expanded to represent the pretreatment system through to the TLP evaporator for the LAW train and the washed sludge for the HLW train. The model was used to investigate alternative operating scenarios, determine the optimum volumetric waste feed ratio of AP-101 to AY-102, and, for each campaign, estimate the simulant and input recycle volumes corresponding to the target glass production rates of 6MT/day HLW glass and 80MT/day LAW glass and scaled to the target of 140L of Campaign I washed sludge. It was designed to quickly achieve steady state and simulation results indicate this was accomplished by Campaign IV. The alternative operating scenarios modeled differed only in the point at which the AP-101 and AY-102 waste feed streams were introduced to the process. The results showed no difference in the production rate between the scenarios. Therefore, for these specific waste feeds the process should be operated to maximize the energy efficiency and minimize scaling in the evaporator by feeding the AY-102 waste feed to the ultra-filtration feed prep tank, bypassing the waste feed evaporator

  4. LOREF: Air cooler optimisation with reduction of ice and frost formation - Optimisation of lamella air-coolers/evaporators of air/water heat pumps - Part 2: mathematical-physical simulation of the lamella air-coolers with condensate and frost formation; LOREF: Luftkuehler-Optimierung mit Reduktion von Eis- und Frostbildung - Optimierung des Lamellenluftkuehlers/Verdampfers von Luft/Wasser-Waermepumpen - Teil 2: mathematisch-physikalische Simulation des Lamellenluftkuehlers mit Kondensat- und Frostbildung

    Energy Technology Data Exchange (ETDEWEB)

    Sahinagic, R.; Gasser, L.; Wellig, B.; Hilfiker, K.

    2008-04-15

    The average coefficient of performance (COP) of air/water heat pumps shall be further improved over the next decade. Its success will strongly depend on two measures: by altering the characteristic of the heat pump through continuous operation instead of on/off operation, and further, by reducing the formation of frost and ice. Frost significantly reduces the air flow, and consequently also the heat and mass transfer in the fin tube evaporator. The formation of frost and ice is influenced by a complex interaction between the fin tube evaporator, the characteristic of the fan and of the heat pump itself. An accurate prediction of these processes is required to optimize the design of the fin tube evaporator in combination with fan and heat pump to further improve the overall efficiency. Based on the theory of simultaneous heat and mass transfer combined with partial condensation and desublimation, a simulation program for the prediction of frost and ice formation has been developed, being valid over the wide range of the ambient air (from -10 {sup o}C to 15 {sup o}C and dry to saturated air). The humidity is deposited either as condensate, frost, ice or as a combination of them on the fins and tubes of the evaporator. It was a major challenge to create a correlation for the physical properties of the frost and ice layer in the unsteady processes. By numerous experiments, four regions of physical properties are distinguished, depending on the temperature at the boundary layer between air and frost or ice: condensate above -2.7 {sup o}C, condensate and ice between -3.5 {sup o}C to -2.7 {sup o}C, ice and frost between -5.2 {sup o}C to -3.5 {sup o}C and frost formed directly by desublimation below -5.2 {sup o}C. A high reliability has been obtained with the mathematical-physical simulation program proven over the entire applicable range of air temperature and humidity, temperature difference for heat transfer, air velocity and geometry of the fin tube evaporator. (author)

  5. Free energy barriers to evaporation of water in hydrophobic confinement.

    Science.gov (United States)

    Sharma, Sumit; Debenedetti, Pablo G

    2012-11-08

    We use umbrella sampling Monte Carlo and forward and reverse forward flux sampling (FFS) simulation techniques to compute the free energy barriers to evaporation of water confined between two hydrophobic surfaces separated by nanoscopic gaps, as a function of the gap width, at 1 bar and 298 K. The evaporation mechanism for small (1 × 1 nm(2)) surfaces is found to be fundamentally different from that for large (3 × 3 nm(2)) surfaces. In the latter case, the evaporation proceeds via the formation of a gap-spanning tubular cavity. The 1 × 1 nm(2) surfaces, in contrast, are too small to accommodate a stable vapor cavity. Accordingly, the associated free energy barriers correspond to the formation of a critical-sized cavity for sufficiently large confining surfaces, and to complete emptying of the gap region for small confining surfaces. The free energy barriers to evaporation were found to be of O(20kT) for 14 Å gaps, and to increase by approximately ~5kT with every 1 Å increase in the gap width. The entropy contribution to the free energy of evaporation was found to be independent of the gap width.

  6. Numerical study of droplet evaporation in an acoustic levitator

    Science.gov (United States)

    Bänsch, Eberhard; Götz, Michael

    2018-03-01

    We present a finite element method for the simulation of all relevant processes of the evaporation of a liquid droplet suspended in an acoustic levitation device. The mathematical model and the numerical implementation take into account heat and mass transfer across the interface between the liquid and gaseous phase and the influence of acoustic streaming on this process, as well as the displacement and deformation of the droplet due to acoustic radiation pressure. We apply this numerical method to several theoretical and experimental examples and compare our results with the well-known d2-law for the evaporation of spherical droplets and with theoretical predictions for the acoustic streaming velocity. We study the influence of acoustic streaming on the distribution of water vapor and temperature in the levitation device, with special attention to the vapor distribution in the emerging toroidal vortices. We also compare the evaporation rate of a droplet with and without acoustic streaming, as well as the evaporation rates in dependence of different temperatures and sound pressure levels. Finally, a simple model of protein inactivation due to heat damage is considered and studied for different evaporation settings and their respective influence on protein damage.

  7. Fish extinctions alter nutrient recycling in tropical freshwaters.

    Science.gov (United States)

    McIntyre, Peter B; Jones, Laura E; Flecker, Alexander S; Vanni, Michael J

    2007-03-13

    There is increasing evidence that species extinctions jeopardize the functioning of ecosystems. Overfishing and other human influences are reducing the diversity and abundance of fish worldwide, but the ecosystem-level consequences of these changes have not been assessed quantitatively. Recycling of nutrients is one important ecosystem process that is directly influenced by fish. Fish species vary widely in the rates at which they excrete nitrogen and phosphorus; thus, altering fish communities could affect nutrient recycling. Here, we use extensive field data on nutrient recycling rates and population sizes of fish species in a Neotropical river and Lake Tanganyika, Africa, to evaluate the effects of simulated extinctions on nutrient recycling. In both of these species-rich ecosystems, recycling was dominated by relatively few species, but contributions of individual species differed between nitrogen and phosphorus. Alternative extinction scenarios produced widely divergent patterns. Loss of the species targeted by fishermen led to faster declines in nutrient recycling than extinctions in order of rarity, body size, or trophic position. However, when surviving species were allowed to increase after extinctions, these compensatory responses had strong moderating effects even after losing many species. Our results underscore the complexity of predicting the consequences of extinctions from species-rich animal communities. Nevertheless, the importance of exploited species in nutrient recycling suggests that overfishing could have particularly detrimental effects on ecosystem functioning.

  8. Quantifying Evaporation in a Permeable Pavement System

    Science.gov (United States)

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  9. Fundamentals of evaporation and condensation phenomena

    International Nuclear Information System (INIS)

    Munir, Z.A.

    1979-01-01

    Fundamental relationships governing evaporation and condensation processes are reviewed. The terrace-ledge-kink (TLK) model is discussed in terms of atomic steps comprising growth and evaporation of crystals. Recent results in the field are described

  10. Foaming in Hanford River Protection Project Waste Treatment Plant LAW Evaporation Processes - FY01 Summary Report

    International Nuclear Information System (INIS)

    Calloway, T.B.

    2002-01-01

    The LAW evaporation processes currently being designed for the Hanford River Protection Project Waste Treatment Plant are subject to foaming. Experimental simulant studies have been conducted in an effort to achieve an effective antifoam agent suitable to mitigate such foaming

  11. Evaporative lithographic patterning of binary colloidal films.

    Science.gov (United States)

    Harris, Daniel J; Conrad, Jacinta C; Lewis, Jennifer A

    2009-12-28

    Evaporative lithography offers a promising new route for patterning a broad array of soft materials. In this approach, a mask is placed above a drying film to create regions of free and hindered evaporation, which drive fluid convection and entrained particles to regions of highest evaporative flux. We show that binary colloidal films exhibit remarkable pattern formation when subjected to a periodic evaporative landscape during drying.

  12. Evaporative cooling in polymer electrolyte fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Shimotori, S; Sonai, A [Toshiba Corp. Tokyo (Japan)

    1996-06-05

    The concept of the evaporative cooling for the internally humidified PEFC was confirmed by the experiment. The evaporative cooling rates at the anode and the cathode were mastered under the various temperatures and air utilizations. At a high temperature the proportion of the evaporative cooling rate to the heat generation rate got higher, the possibility of the evaporative cooling was demonstrated. 2 refs., 7 figs., 1 tab.

  13. Environmental aspects of recycling

    International Nuclear Information System (INIS)

    Jansma, R.; Van Gemert, F.

    2001-01-01

    Advanced recycling options were studied. Emphasis was on the production of high-level waste. All other impacts, e.g. emissions, were considered to be of minor importance, since from a technical point of view they can be limited to any desired extent. An objective was to gather data from the industry and to use them in a Life Cycle Analysis (LCA) of several fuel cycle options. It was necessary to complete our data set with literature data. At the end of our project we could benefit from the results of several Expert Working Groups of OECD/NEA. Detailed information was available for the once-through fuel cycle (OFC) and the fuel cycle with mono recycling of MOX. For the other more advanced fuel cycle options information was of a more qualitative nature. The established set of data was sufficient to conduct a streamlined LCA with focus on waste production for final disposal. Some remarks should be made before comparing the various fuel cycle options studied. The first relates to plutonium that contributes to more than 90% of the radiotoxicity of the spent fuel for more than 1000 centuries. Large concern for transmutation of minor actinides will disproportional if plutonium itself is not eliminated. The second remark is that the fission products contribute potentially very little to the radiotoxicity especially when some long-lived radionuclides after separation are imprisoned in stable matrices to prevent them to be carried by underground water. From all nuclear fuel cycles considered, the MIX cycle in LWRs, with recycling of plutonium and minor actinides has the lowest minor actinides production (0.018 kg/TW e h) and the plutonium production is also quite low (0.06 kg/TW e h). The MIX cycle without minor actinides recycling performs a little better with respect to plutonium production (0.04 kg/TW e h) but has a relatively high minor actinides production (8.7 kg/TW e h). Another conclusion is that burning of minor actinides in fast reactors (MA 0.28 kg/TW e h, Pu 0

  14. Text recycling: acceptable or misconduct?

    Science.gov (United States)

    Harriman, Stephanie; Patel, Jigisha

    2014-08-16

    Text recycling, also referred to as self-plagiarism, is the reproduction of an author's own text from a previous publication in a new publication. Opinions on the acceptability of this practice vary, with some viewing it as acceptable and efficient, and others as misleading and unacceptable. In light of the lack of consensus, journal editors often have difficulty deciding how to act upon the discovery of text recycling. In response to these difficulties, we have created a set of guidelines for journal editors on how to deal with text recycling. In this editorial, we discuss some of the challenges of developing these guidelines, and how authors can avoid undisclosed text recycling.

  15. Emulsified industrial oils recycling

    Energy Technology Data Exchange (ETDEWEB)

    Gabris, T.

    1982-04-01

    The industrial lubricant market has been analyzed with emphasis on current and/or developing recycling and re-refining technologies. This task has been performed for the United States and other industrialized countries, specifically France, West Germany, Italy and Japan. Attention has been focused at emulsion-type fluids regardless of the industrial application involved. It was found that emulsion-type fluids in the United States represent a much higher percentage of the total fluids used than in other industrialized countries. While recycling is an active matter explored by the industry, re-refining is rather a result of other issues than the mere fact that oil can be regenerated from a used industrial emulsion. To extend the longevity of an emulsion is a logical step to keep expenses down by using the emulsion as long as possible. There is, however, another important factor influencing this issue: regulations governing the disposal of such fluids. The ecological question, the respect for nature and the natural balances, is often seen now as everybody's task. Regulations forbid dumping used emulsions in the environment without prior treatment of the water phase and separation of the oil phase. This is a costly procedure, so recycling is attractive since it postpones the problem. It is questionable whether re-refining of these emulsions - as a business - could stand on its own if these emulsions did not have to be taken apart for disposal purposes. Once the emulsion is separated into a water and an oil phase, however, re-refining of the oil does become economical.

  16. New models for droplet heating and evaporation

    KAUST Repository

    Sazhin, Sergei S.; Elwardani, Ahmed Elsaid; Gusev, Ivan G.; Xie, Jianfei; Shishkova, Irina N.; Cao, Bingyang; Snegirev, Alexander Yu.; Heikal, Morgan Raymond

    2013-01-01

    and evaporation, taking into account the effects of the moving boundary due to evaporation, hydrodynamic models of multi-component droplet heating and evaporation, taking and not taking into account the effects of the moving boundary, new kinetic models of mono

  17. Evaporation from a sphagnum moss surface

    Science.gov (United States)

    D.S. Nichols; J.M. Brown

    1980-01-01

    Peat cores, 45 cm in diameter, were collected from a sphagnum bog in northern Minnesota, and used to measure the effects of different temperatures and water levels on evaporation from a sphagnum moss surface in a growth chamber. Under all conditions, evaporation from the moss surface was greater than that from a free-water surface. Evaporation from the moss increased...

  18. An evaporation driven pump for microfluidics applications

    NARCIS (Netherlands)

    Nie, C.; Mandamparambil, R.; Frijns, A.J.H.; den Toonder, J.M.J.; Tadrist, L.; Graur, I.

    2014-01-01

    We present an evaporation driven micro-pump for micro fluidic applications on a foil. In such a device, the evaporation rate is controlled by the geometry of the channel outlet and its temperature. The evaporation is also influenced by environmental parameters such as air humidity and temperature.

  19. Investigation of a novel dew point indirect evaporative air conditioning system for buildings

    OpenAIRE

    Duan, Zhiyin

    2011-01-01

    This study aims to improve the performance of existing indirect evaporative coolers. A new dew point indirect evaporative cooler with counter-current heat/mass exchanger was developed in this research by optimal design, material selection, numerical simulation, experimental investigations and economic, environmental, regional acceptance analysis. A new dew point heat/mass exchanger using a counter-current flow pattern was designed by numerical simulation in terms of material, structure, g...

  20. Recycle Glass in Foam Glass Production

    DEFF Research Database (Denmark)

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

  1. Changes in precipitation recycling over arid regions in the Northern Hemisphere

    Science.gov (United States)

    Li, Ruolin; Wang, Chenghai; Wu, Di

    2018-01-01

    Changes of precipitation recycling (PR) in Northern Hemisphere from 1981 to 2010 are investigated using a water recycling model. The temporal and spatial characteristics of recycling in arid regions are analyzed. The results show that the regional precipitation recycling ratio (PRR) in arid regions is larger than in wet regions. PRR in arid regions has obvious seasonal variation, ranging from more than 25 % to less than 1 %. Furthermore, in arid regions, PRR is significantly negatively correlated with precipitation (correlation coefficient r = -0.5, exceeding the 99 % significance level). Moreover, the trend of PRR is related to changes in precipitation in two ways. PRR decreases with increasing precipitation in North Africa, which implies that less locally evaporated vapor converts into actual precipitation. However, in Asian arid regions, the PRR increases as precipitation reduces, which implies that more locally evaporated vapor converts into rainfall. Further, as PRR mainly depends on evapotranspiration, the PRR trend in Asian arid regions develops as temperature increases and more evaporated vapor enters the atmosphere to offset the reduced rainfall.

  2. Water Evaporation in Swimming Baths

    DEFF Research Database (Denmark)

    Hyldgård, Carl-Erik

    This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which are repres......This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which...... are represented in instructions for carrying out and running swimming baths. If you follow the instructions you can achieve less investments, less heat consumption and a better comfort to the bathers....

  3. Black hole evaporation: a paradigm

    International Nuclear Information System (INIS)

    Ashtekar, Abhay; Bojowald, Martin

    2005-01-01

    A paradigm describing black hole evaporation in non-perturbative quantum gravity is developed by combining two sets of detailed results: (i) resolution of the Schwarzschild singularity using quantum geometry methods and (ii) time evolution of black holes in the trapping and dynamical horizon frameworks. Quantum geometry effects introduce a major modification in the traditional spacetime diagram of black hole evaporation, providing a possible mechanism for recovery of information that is classically lost in the process of black hole formation. The paradigm is developed directly in the Lorentzian regime and necessary conditions for its viability are discussed. If these conditions are met, much of the tension between expectations based on spacetime geometry and structure of quantum theory would be resolved

  4. Duplex Tear Film Evaporation Analysis.

    Science.gov (United States)

    Stapf, M R; Braun, R J; King-Smith, P E

    2017-12-01

    Tear film thinning, hyperosmolarity, and breakup can cause irritation and damage to the human eye, and these form an area of active investigation for dry eye syndrome research. Recent research demonstrates that deficiencies in the lipid layer may cause locally increased evaporation, inducing conditions for breakup. In this paper, we explore the conditions for tear film breakup by considering a model for tear film dynamics with two mobile fluid layers, the aqueous and lipid layers. In addition, we include the effects of osmosis, evaporation as modified by the lipid, and the polar portion of the lipid layer. We solve the system numerically for reasonable parameter values and initial conditions and analyze how shifts in these cause changes to the system's dynamics.

  5. Dew Point Evaporative Comfort Cooling

    Science.gov (United States)

    2012-11-01

    Multiple DASs were installed at Fort Carson, and the data from all the sensors were stored and partially processed on Campbell Scientific Data Loggers. The...evaporative cooling technologies would be expected to easily overcome utility- scale water withdrawal rates. As an example, an evaluation of an...Ambient pressure Outdoor Setra 276 1% of full scale Pyranometer Horizontal Campbell Scientific CS300 5% of daily total The OAT measurement has an

  6. Experimental results on evaporation waves

    Science.gov (United States)

    Grana Otero, Jose; Parra Fabian, Ignacio

    2010-11-01

    A liquid contained in a vertical glass tube is suddenly depressurized from a high initial pressure down to one for which the stable state is vapour, so vaporization sets off at the free surface. For large enough evaporation rates, the planar vapour-liquid interface is Darrieus-Landau unstable [1], leading to the interface surface rippling close to the instability threshold. Further increasing the initial to final pressure ratio brings about evaporation waves [2,3], in which a highly corrugated front propagates downwards into the liquid. A new experimental method is presented as well as some experimental results obtained by tracking the evolution of the front with a high speed camera. In addition, a number of new phenomena related to the dynamics of bubbles growth at the walls has been uncovered. In particular, a new mode of propagation of the evaporation front is found. In this mode the front originates from below the interface, so the propagation is upwards against gravity with a curved but smooth front.[4pt] [1] F. J. Higuera, Phys. Fluids, V. 30, 679 (1987).[0pt] [2] J.E.Shepherd and B.Sturtevant, J.Fluid Mech., V.121,379 (1982).[0pt] [3] P.Reinke and G.Yadigaroglu, Int.J.Multiph. Flow, V.27,1487 (2001).

  7. Improvements of evaporation drag model

    International Nuclear Information System (INIS)

    Li Xiaoyan; Yang Yanhua; Xu Jijun

    2004-01-01

    A special observable experiment facility has been established, and a series of experiments have been carried out on this facility by pouring one or several high-temperature particles into a water pool. The experiment has verified the evaporation drag model, which believe the non-symmetric profile of the local evaporation rate and the local density of the vapor would bring about a resultant force on the hot particle so as to resist its motion. However, in Yang's evaporation drag model, radiation heat transfer is taken as the only way to transfer heat from hot particle to the vapor-liquid interface and all of the radiation energy is deposited on the vapor-liquid interface, thus contributing to the vaporization rate and mass balance of the vapor film. So, the heat conduction and the heat convection are taken into account in improved model. At the same time, the improved model given by this paper presented calculations of the effect of hot particles temperature on the radiation absorption behavior of water

  8. Cooling clothing utilizing water evaporation

    DEFF Research Database (Denmark)

    Sakoi, Tomonori; Tominaga, Naoto; Melikov, Arsen Krikor

    2014-01-01

    . To prevent wet discomfort, the T-shirt was made of a polyester material having a water-repellent silicon coating on the inner surface. The chest, front upper arms, and nape of the neck were adopted as the cooling areas of the human body. We conducted human subject experiments in an office with air......We developed cooling clothing that utilizes water evaporation to cool the human body and has a mechanism to control the cooling intensity. Clean water was supplied to the outer surface of the T-shirt of the cooling clothing, and a small fan was used to enhance evaporation on this outer surface...... temperature ranging from 27.4 to 30.7 °C to establish a suitable water supply control method. A water supply control method that prevents water accumulation in the T-shirt and water dribbling was validated; this method is established based on the concept of the water evaporation capacity under the applied...

  9. Behaviour of Recycled Coarse Aggregate Concrete: Age and Successive Recycling

    Science.gov (United States)

    Sahoo, Kirtikanta; Pathappilly, Robin Davis; Sarkar, Pradip

    2016-06-01

    Recycled Coarse Aggregate (RCA) concrete construction technique can be called as `green concrete', as it minimizes the environmental hazard of the concrete waste disposal. Indian standard recommends target mean compressive strength of the conventional concrete in terms of water cement ratio ( w/ c). The present work is an attempt to study the behaviour of RCA concrete from two samples of parent concrete having different age group with regard to the relationship of compressive strength with water cement ratios. Number of recycling may influence the mechanical properties of RCA concrete. The influence of age and successive recycling on the properties such as capillary water absorption, drying shrinkage strain, air content, flexural strength and tensile splitting strength of the RCA concrete are examined. The relationship between compressive strength at different w/ c ratios obtained experimentally is investigated for the two parameters such as age of parent concrete and successive recycling. The recycled concrete using older recycled aggregate shows poor quality. While the compressive strength reduces with successive recycling gradually, the capillary water absorption increases abruptly, which leads to the conclusion that further recycling may not be advisable.

  10. Recovery of recycled acrylonitrile-butadiene-styrene, through mixing with styrene-ethylene/butylene-styrene

    OpenAIRE

    Peydro, M. A.; Parres, F.; Crespo Amorós, José Enrique; Navarro Vidal, Raúl

    2013-01-01

    Recovery of recycled acrylonitrile-butadiene-styrene (ABS) through mixing with styrene-ethylene/butylene-styrene (SEBS) has been studied in this paper. To simulate recycled ABS, virgin ABS was processed through 5 cycles, at extreme processing temperatures, 220 degrees C and 260 degrees C. The virgin ABS, the virgin SEBS, the recycled ABS and the mixtures were mechanically, thermally and rheologically characterized after the various cycles of reprocessing in order to evaluate their correspondi...

  11. Open-loop recycling: A LCA case study of PET bottle-to-fibre-recycling

    NARCIS (Netherlands)

    Shen, L.; Worrell, E.; Patel, M.K.

    2010-01-01

    This study assesses the environmental impact of polyethylene terephthalate (PET) bottle-to-fibre recycling using the methodology of life-cycle assessment (LCA). Four recycling cases, including mechanical recycling, semi-mechanical recycling, back-to-oligomer recycling and back-to-monomer recycling

  12. Waste material recycling: Assessment of contaminants limiting recycling

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn

    systematically investigated. This PhD project provided detailed quantitative data following a consistent approach to assess potential limitations for the presence of chemicals in relation to material recycling. Paper and plastics were used as illustrative examples of materials with well-established recycling...... schemes and great potential for increase in recycling, respectively. The approach followed in the present work was developed and performed in four distinct steps. As step one, fractional composition of waste paper (30 fractions) and plastics (9 fractions) from households in Åbenrå municipality (Southern...... detrimental to their recycling. Finally, a material flow analysis (MFA) approach revealed the potential for accumulation and spreading of contaminants in material recycling, on the example of the European paper cycle. Assessment of potential mitigation measures indicated that prevention of chemical use...

  13. Resources, recycle, and substitution

    International Nuclear Information System (INIS)

    Wymer, R.G.

    A two-fold strategy appears necessary to ensure that the resource needs of the developed and developing nations are met. First, recycle and substitution must be encouraged in those instances where they do find application. Although these measures have limited applicability, they may be of vital importance in those instances where they do apply; in any event, they buy time. Second, practical and economical technologies must be developed to exploit the lower-grade and marginal ores and the oftentimes abundant but highly refractory ores, as well as to greatly increase the recovery of secondary elements present in the ores - elements whose form and amounts in the ores make them economically unrecoverable by themselves, but which are economically recoverable as by-products. It is often the case that if these elements are not recovered during the initial mining and milling operations, they are rendered unrecoverable, in a practical sense, forever. Furthermore, they may even become environmental pollutants. Specific examples of recovery from refractory ores, by-product recovery, and recycle are given. Also, some suggestions of substitutes for important resources are tabulated

  14. Heat and mass transfer analogies for evaporation models at high evaporation rate

    OpenAIRE

    Trontin , P.; Villedieu , P.

    2014-01-01

    International audience; In the framework of anti and deicing applications, heated liquid films can appear above the ice thickness, or directly above the wall. Then, evaporation plays a major role in the Messinger balance and evaporated mass has to be predicted accurately. Unfortunately, it appears that existing models under-estimate evaporation at high temperature. In this study, different evaporation models at high evaporation rates are studied. The different hypothesis on which these models...

  15. Simulations

    CERN Document Server

    Ngada, Narcisse

    2015-06-15

    The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.

  16. Recycling Pressure-Sensitive Products

    Science.gov (United States)

    Jihui Guo; Larry Gwin; Carl Houtman; Mark Kroll; Steven J. Severtson

    2012-01-01

    The efficient control of contaminants such as metals, plastics, inks and adhesives during the processing of recovered paper products determines the profitability of recycling mills. In fact, it is arguably the most important technical obstacle in expanding the use of recycled paper.1-4 An especially challenging category of contaminants to manage...

  17. The Dynamic Earth: Recycling Naturally!

    Science.gov (United States)

    Goldston, M. Jenice; Allison, Elizabeth; Fowler, Lisa; Glaze, Amanda

    2013-01-01

    This article begins with a thought-provoking question: What do you think of when you hear the term "recycle?" Many think about paper, glass, aluminum cans, landfills, and reducing waste by reusing some of these materials. How many of us ever consider the way the systems of Earth dynamically recycle its materials? In the following…

  18. Does evaporation paradox exist in China?

    Directory of Open Access Journals (Sweden)

    Z. T. Cong

    2009-03-01

    Full Text Available One expected consequence of global warming is the increase in evaporation. However, lots of observations show that the rate of evaporation from open pans of water has been steadily decreasing all over the world in the past 50 years. The contrast between expectation and observation is called "evaporation paradox". Based on data from 317 weather stations in China from 1956 to 2005, the trends of pan evaporation and air temperature were obtained and evaporation paradox was analyzed. The conclusions include: (1 From 1956 to 2005, pan evaporation paradox existed in China as a whole while pan evaporation kept decreasing and air temperature became warmer and warmer, but it does not apply to Northeast and Southeast China; (2 From 1956 to 1985, pan evaporation paradox existed narrowly as a whole with unobvious climate warming trend, but it does not apply to Northeast China; (3 From 1986 to 2005, in the past 20 years, pan evaporation paradox did not exist for the whole period while pan evaporation kept increasing, although it existed in South China. Furthermore, the trend of other weather factors including sunshine duration, windspeed, humidity and vapor pressure deficit, and their relations with pan evaporation are discussed. As a result, it can be concluded that pan evaporation decreasing is caused by the decreasing in radiation and wind speed before 1985 and pan evaporation increasing is caused by the decreasing in vapor pressure deficit due to strong warming after 1986. With the Budyko curve, it can be concluded that the actual evaporation decreased in the former 30 years and increased in the latter 20 year for the whole China.

  19. Technology options for future recycling

    International Nuclear Information System (INIS)

    Kikuchi, T.

    2001-01-01

    Recycling of nuclear material is indispensable, not only for using valuable resources but also for reducing the debt which we may leave to the next generations. Advanced reprocessing technologies have been developed in several countries to deal with the diversification of nuclear fuels. Also technologies derived from reprocessing or other fuel cycle areas have continued to be developed in terms of recycling. Cost effectiveness and waste-free processing are increasingly important factors in the applicable of an alternate recycling policy. This paper introduces an example of the studies in this field conducted in some countries including Japan and considers the establishment of effective recycling methodologies taking into account the uncertainty of future recycling policy. (author)

  20. Space Plastic Recycling System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Techshot's proposed Space Plastic Recycler (SPR) is an automated closed loop plastic recycling system that allows the automated conversion of disposable ISS...

  1. Actinide recycling in reactors

    International Nuclear Information System (INIS)

    Kuesters, H.; Wiese, H.W.; Krieg, B.

    1995-01-01

    The objective is an assessment of the transmutation of long-lived actinides and fission products and the incineration of plutonium for reducing the risk potential of radioactive waste from reactors in comparison to direct waste disposal. The contribution gives an interim account on homogeneous and heterogeneous recycling of 'risk nuclides' in thermal and fast reactors. Important results: - A homogeneous 5 percent admixture of minor actinides (MA) from N4-PWRs to EFR fuel would allow a transmutation not only of the EFR MA, but in addition of the MA from 5 or 6 PWRs of equal power. However, the incineration is restricted by safety considerations. - LWR have only a very low MA incineration potential, due to their disadvantageous neutron capture/fission ratio. - In order to keep the Cm inventory at a low level, it is advantageous to concentrate the Am heterogeneously in particular fuel elements or rods. (orig./HP)

  2. Recycling of plastics

    Energy Technology Data Exchange (ETDEWEB)

    Kaminsky, W; Menzel, J; Sinn, H

    1976-01-01

    Considering the shortage of raw materials and environmental pollution, the recycling of plastic waste is a very important topic. Pilot plants for research in Funabashi Japan, Franklin (Ohio) U.S.A., and the R 80-process of Krauss Maffei, W. Germany, have demonstrated the possibility of reclaiming plastics from refuse. Old tires and waste from the plastic producing and manufacturing industries are readily available. The pyrolysis of plastic yields gaseous and liquid products, and the exploitation of this cracking reaction has been demonstrated by pilot plants in Japan and Great Britain. Further laboratory scale experiments are taking place in W. Germany. In continuous fluidized beds and in molten salts, polyethylene, polypropylene, polyvinylchloride, polystyrene and rubber are pyrolysed and better than 98 percent conversion is obtained. Up to 40 percent of the feed can be obtained as aromatic compounds, and a pilot plant is under construction. As a first step PVC-containing material can be almost quantitatively dehydrochlorinated.

  3. Recycling microcavity optical biosensors.

    Science.gov (United States)

    Hunt, Heather K; Armani, Andrea M

    2011-04-01

    Optical biosensors have tremendous potential for commercial applications in medical diagnostics, environmental monitoring, and food safety evaluation. In these applications, sensor reuse is desirable to reduce costs. To achieve this, harsh, wet chemistry treatments are required to remove surface chemistry from the sensor, typically resulting in reduced sensor performance and increased noise due to recognition moiety and optical transducer degradation. In the present work, we suggest an alternative, dry-chemistry method, based on O2 plasma treatment. This approach is compatible with typical fabrication of substrate-based optical transducers. This treatment completely removes the recognition moiety, allowing the transducer surface to be refreshed with new recognition elements and thus enabling the sensor to be recycled.

  4. Physics of plutonium recycling

    International Nuclear Information System (INIS)

    2003-01-01

    The commercial recycling of plutonium as PuO 2 /UO 2 mixed-oxide (MOX) fuel is an established practice in pressurised water reactors (PWRs) in several countries, the main motivation being the consumption of plutonium arising from spent fuel reprocessing. Although the same motivating factors apply in the case of boiling water reactors (BWRs), they have lagged behind PWRs for various reasons, and MOX utilisation in BWRs has been implemented in only a few reactors to date. One of the reasons is that the nuclear design of BWR MOX assemblies (or bundles) is more complex than that of PWR assemblies. Recognizing the need and the timeliness to address this issue at the international level, the OECD/NEA Working Party on the Physics of Plutonium Fuels and Innovative Fuel Cycles (WPPR) conducted a physics code benchmark test for a BWR assembly. This volume reports on the benchmark results and conclusions that can be drawn from it. (authors)

  5. Formation of coffee-stain patterns at the nanoscale: The role of nanoparticle solubility and solvent evaporation rate.

    Science.gov (United States)

    Zhang, Jianguo; Milzetti, Jasmin; Leroy, Frédéric; Müller-Plathe, Florian

    2017-03-21

    When droplets of nanoparticle suspension evaporate from surfaces, they leave behind a deposit of nanoparticles. The mechanism of evaporation-induced pattern formation in the deposit is studied by molecular dynamics simulations for sessile nanodroplets. The influence of the interaction between nanoparticles and liquid molecules and the influence of the evaporation rate on the final deposition pattern are addressed. When the nanoparticle-liquid interaction is weaker than the liquid-liquid interaction, an interaction-driven or evaporation-induced layer of nanoparticles appears at the liquid-vapor interface and eventually collapses onto the solid surface to form a uniform deposit independently of the evaporation rate. When the nanoparticle-liquid and liquid-liquid interactions are comparable, the nanoparticles are dispersed inside the droplet and evaporation takes place with the contact line pinned at a surface defect. In such a case, a pattern with an approximate ring-like shape is found with fast evaporation, while a more uniform distribution is observed with slower evaporation. When the liquid-nanoparticle interaction is stronger than the liquid-liquid interaction, evaporation always occurs with receding contact line. The final deposition pattern changes from volcano-like to pancake-like with decreasing evaporation rate. These findings might help to design nanoscale structures like nanopatterns or nanowires on surface through controlled solvent evaporation.

  6. Capillary condensation and evaporation in alumina nanopores with controlled modulations.

    Science.gov (United States)

    Bruschi, Lorenzo; Mistura, Giampaolo; Liu, Lifeng; Lee, Woo; Gösele, Ulrich; Coasne, Benoit

    2010-07-20

    Capillary condensation in nanoporous anodic aluminum oxide presenting not interconnected pores with controlled modulations is studied using adsorption experiments and molecular simulations. Both the experimental and simulation data show that capillary condensation and evaporation are driven by the smallest size of the nanopore (constriction). The adsorption isotherms for the open and closed pores are almost identical if constrictions are added to the system. The latter result implies that the type of pore ending does not matter in modulated pores. Thus, the presence of hysteresis loops observed in adsorption isotherms measured in straight nanopores with closed bottom ends can be explained in terms of geometrical inhomogeneities along the pore axis. More generally, these results provide a general picture of capillary condensation and evaporation in constricted or modulated pores that can be used for the interpretation of adsorption in disordered porous materials.

  7. Evaporative oxidation treatability test report

    International Nuclear Information System (INIS)

    1995-04-01

    In 1992, Congress passed the Federal Facilities Compliance Act that requires the U.S. Department of Energy (DOE) to treat and dispose of its mixed waste in accordance with the Resource Conservation and Recovery Act (RCRA) land disposal restrictions (LDRs). In response to the need for mixed-waste treatment capacity where available off-site commercial treatment facilities do not exist or cannot be used, the DOE Albuquerque Operations Office (DOE-AL) organized a Treatment Selection Team to match mixed wastes with treatment options and develop a strategy for treatment of its mixed wastes. DOE-AL manages operations at nine sites with mixed-waste inventories. The Treatment Selection Team determined a need to develop mobile treatment capacity to treat wastes at the sites where the wastes are generated. Treatment processes used for mixed waste not only must address the hazardous component (i.e., meet LDRs) but also must contain the radioactive component in a form that allows final disposal while protecting workers, the public, and the environment. On the basis of recommendations of the Treatment Selection Team, DOE-AL assigned projects to the sites to bring mixed-waste treatment capacity on-line. The three technologies assigned to the DOE Grand Junction Projects Office (GJPO) are evaporative oxidation, thermal desorption, and treated wastewater evaporation. Rust Geotech, the DOE-GJPO prime contractor, was assigned to design and fabricate mobile treatment units (MTUs) for these three technologies and to deliver the MTUs to selected DOE-AL sites. To conduct treatability tests at the GJPO, Rust leased a pilot-scale evaporative oxidation unit from the Clemson Technical Center (CTC), Anderson, South Carolina. The purpose of this report is to document the findings and results of tests performed using this equipment

  8. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Ziemkiewicz, Paul; Vandivort, Tamara; Pflughoeft-Hassett, Debra; Chugh, Y Paul; Hower, James

    2008-08-31

    Each year, over 100 million tons of solid byproducts are produced by coal-burning electric utilities in the United States. Annual production of flue gas desulfurization (FGD) byproducts continues to increase as the result of more stringent sulfur emission restrictions. In addition, stricter limits on NOx emissions mandated by the 1990 Clean Air Act have resulted in utility burner/boiler modifications that frequently yield higher carbon concentrations in fly ash, which restricts the use of the ash as a cement replacement. Controlling ammonia in ash is also of concern. If newer, “clean coal” combustion and gasification technologies are adopted, their byproducts may also present a management challenge. The objective of the Combustion Byproducts Recycling Consortium (CBRC) is to develop and demonstrate technologies to address issues related to the recycling of byproducts associated with coal combustion processes. A goal of CBRC is that these technologies, by the year 2010, will lead to an overall ash utilization rate from the current 34% to 50% by such measures as increasing the current rate of FGD byproduct use and increasing in the number of uses considered “allowable” under state regulations. Another issue of interest to the CBRC would be to examine the environmental impact of both byproduct utilization and disposal. No byproduct utilization technology is likely to be adopted by industry unless it is more cost-effective than landfilling. Therefore, it is extremely important that the utility industry provide guidance to the R&D program. Government agencies and privatesector organizations that may be able to utilize these materials in the conduct of their missions should also provide input. The CBRC will serve as an effective vehicle for acquiring and maintaining guidance from these diverse organizations so that the proper balance in the R&D program is achieved.

  9. Enhancement of Water Evaporation on Solid Surfaces with Nanoscale Hydrophobic-Hydrophilic Patterns.

    Science.gov (United States)

    Wan, Rongzheng; Wang, Chunlei; Lei, Xiaoling; Zhou, Guoquan; Fang, Haiping

    2015-11-06

    Using molecular dynamics simulations, we show that the evaporation of nanoscale water on hydrophobic-hydrophilic patterned surfaces is unexpectedly faster than that on any surfaces with uniform wettability. The key to this phenomenon is that, on the patterned surface, the evaporation rate from the hydrophilic region only slightly decreases due to the correspondingly increased water thickness; meanwhile, a considerable number of water molecules evaporate from the hydrophobic region despite the lack of water film. Most of the evaporated water from the hydrophobic region originates from the hydrophilic region by diffusing across the contact lines. Further analysis shows that the evaporation rate from the hydrophobic region is approximately proportional to the total length of the contact lines.

  10. Sub- and super-Maxwellian evaporation of simple gases from liquid water

    International Nuclear Information System (INIS)

    Kann, Z. R.; Skinner, J. L.

    2016-01-01

    Non-Maxwellian evaporation of light atoms and molecules (particles) such as He and H 2 from liquids has been observed experimentally. In this work, we use simulations to study systematically the evaporation of Lennard-Jones particles from liquid water. We find instances of sub- and super-Maxwellian evaporation, depending on the mass of the particle and the particle-water interaction strength. The observed trends are in qualitative agreement with experiment. We interpret these trends in terms of the potential of mean force and the effectiveness and frequency of collisions during the evaporation process. The angular distribution of evaporating particles is also analyzed, and it is shown that trends in the energy from velocity components tangential and normal to the liquid surface must be understood separately in order to interpret properly the angular distributions.

  11. Sub- and super-Maxwellian evaporation of simple gases from liquid water

    Energy Technology Data Exchange (ETDEWEB)

    Kann, Z. R.; Skinner, J. L., E-mail: skinner@chem.wisc.edu [Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706 (United States)

    2016-04-21

    Non-Maxwellian evaporation of light atoms and molecules (particles) such as He and H{sub 2} from liquids has been observed experimentally. In this work, we use simulations to study systematically the evaporation of Lennard-Jones particles from liquid water. We find instances of sub- and super-Maxwellian evaporation, depending on the mass of the particle and the particle-water interaction strength. The observed trends are in qualitative agreement with experiment. We interpret these trends in terms of the potential of mean force and the effectiveness and frequency of collisions during the evaporation process. The angular distribution of evaporating particles is also analyzed, and it is shown that trends in the energy from velocity components tangential and normal to the liquid surface must be understood separately in order to interpret properly the angular distributions.

  12. Mean-field kinetic theory approach to evaporation of a binary liquid into vacuum

    Science.gov (United States)

    Frezzotti, A.; Gibelli, L.; Lockerby, D. A.; Sprittles, J. E.

    2018-05-01

    Evaporation of a binary liquid into near-vacuum conditions has been studied using numerical solutions of a system of two coupled Enskog-Vlasov equations. Liquid-vapor coexistence curves have been mapped out for different liquid compositions. The evaporation process has been investigated at a range of liquid temperatures sufficiently lower than the critical one for the vapor not to significantly deviate from the ideal behavior. It is found that the shape of the distribution functions of evaporating atoms is well approximated by an anisotropic Maxwellian distribution with different characteristic temperatures for velocity components normal and parallel to the liquid-vapor interface. The anisotropy reduces as the evaporation temperature decreases. Evaporation coefficients are computed based on the separation temperature and the maximum concentration of the less volatile component close to the liquid-vapor interface. This choice leads to values which are almost constant in the simulation conditions.

  13. Specificity Switching Pathways in Thermal and Mass Evaporation of Multicomponent Hydrocarbon Droplets: A Mesoscopic Observation.

    Science.gov (United States)

    Nasiri, Rasoul; Luo, Kai H

    2017-07-10

    For well over one century, the Hertz-Knudsen equation has established the relationship between thermal - mass transfer coefficients through a liquid - vapour interface and evaporation rate. These coefficients, however, have been often separately estimated for one-component equilibrium systems and their simultaneous influences on evaporation rate of fuel droplets in multicomponent systems have yet to be investigated at the atomic level. Here we first apply atomistic simulation techniques and quantum/statistical mechanics methods to understand how thermal and mass evaporation effects are controlled kinetically/thermodynamically. We then present a new development of a hybrid method of quantum transition state theory/improved kinetic gas theory, for multicomponent hydrocarbon systems to investigate how concerted-distinct conformational changes of hydrocarbons at the interface affect the evaporation rate. The results of this work provide an important physical concept in fundamental understanding of atomistic pathways in topological interface transitions of chain molecules, resolving an open problem in kinetics of fuel droplets evaporation.

  14. Evaporation of nanoscale water on a uniformly complete wetting surface at different temperatures.

    Science.gov (United States)

    Guo, Yuwei; Wan, Rongzheng

    2018-05-03

    The evaporation of nanoscale water films on surfaces affects many processes in nature and industry. Using molecular dynamics (MD) simulations, we show the evaporation of a nanoscale water film on a uniformly complete wetting surface at different temperatures. With the increase in temperature, the growth of the water evaporation rate becomes slow. Analyses show that the hydrogen bond (H-bond) lifetimes and orientational autocorrelation times of the outermost water film decrease slowly with the increase in temperature. Compared to a thicker water film, the H-bond lifetimes and orientational autocorrelation times of a monolayer water film are much slower. This suggests that the lower evaporation rate of the monolayer water film on a uniformly complete wetting surface may be caused by the constriction of the water rotation due to the substrate. This finding may be helpful for controlling nanoscale water evaporation within a certain range of temperatures.

  15. Evaporation From Soil Containers With Irregular Shapes

    Science.gov (United States)

    Assouline, Shmuel; Narkis, Kfir

    2017-11-01

    Evaporation from bare soils under laboratory conditions is generally studied using containers of regular shapes where the vertical edges are parallel to the flow lines in the drying domain. The main objective of this study was to investigate the impact of irregular container shapes, for which the flow lines either converge or diverge toward the surface. Evaporation from initially saturated sand and sandy loam soils packed in cones and inverted cones was compared to evaporation from corresponding cylindrical columns. The initial evaporation rate was higher in the cones, and close to potential evaporation. At the end of the experiment, the cumulative evaporation depth in the sand cone was equal to that in the column but higher than in the inverted cone, while in the sandy loam, the order was cone > column > inverted cone. By comparison to the column, stage 1 evaporation was longer in the cones, and practically similar in the inverted cones. Stage 2 evaporation rate decreased with the increase of the evaporating surface area. These results were more pronounced in the sandy loam. For the sand column, the transition between stage 1 and stage 2 evaporation occurred when the depth of the saturation front was approximately equal to the characteristic length of the soil. However, for the cone and the inverted cone, it occurred for a shallower depth of the saturation front. It seems therefore that the concept of the characteristic length derived from the soil hydraulic properties is related to drying systems of regular shapes.

  16. Development and Analysis of Desiccant Enhanced Evaporative Air Conditioner Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, E.; Woods, J.; Judkoff, R.

    2012-04-01

    This report documents the design of a desiccant enhanced evaporative air conditioner (DEVAP AC) prototype and the testing to prove its performance. Previous numerical modeling and building energy simulations indicate a DEVAP AC can save significant energy compared to a conventional vapor compression AC (Kozubal et al. 2011). The purposes of this research were to build DEVAP prototypes, test them to validate the numerical model, and identify potential commercialization barriers.

  17. Stable Isotope Mass Balance of the Laurentian Great Lakes to Constrain Evaporative Losses

    Energy Technology Data Exchange (ETDEWEB)

    Jasechko, S. [Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario and Alberta Innovates, Technology Futures, Victoria, British Columbia (Canada); Gibson, J. J. [Canada Alberta Innovates, Technology Futures, Victoria, British Columbia and Department of Geography, University of Victoria, Victoria, British Columbia (Canada); Pietroniro, A. [National Water Research Institute, Environment Canada, Saskatoon, Saskatchewan (Canada); Edwards, T.W D. [Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario (Canada)

    2013-07-15

    Evaporation is an important yet poorly constrained component of the water budget of the Laurentian Great Lakes, but is known historically to have a significant impact on regional climate, including enhanced humidity and downwind lake effect precipitation. Sparse over lake climate monitoring continues to limit ability to quantify bulk lake evaporation and precipitation rates by physical measurements, impeded by logistical difficulties and costs of instrumenting large areas of open water (10{sup 3}-10{sup 5} km2). Measurements of stable isotopes of oxygen and hydrogen in water samples of precipitation and surface waters within the great lakes basin are used to better understand the controls on the region's water cycle. A stable isotope mass balance approach to calculate long term evaporation as a proportion of input to each lake is discussed. The approach capitalizes on the well understood systematic isotopic separation of an evaporating water body, but includes added considerations for internal recycling of evaporated moisture in the overlying atmosphere that should be incorporated for surface waters sufficiently large to significantly influence surrounding climate. (author)

  18. Preliminary Geological Findings on the BP-1 Simulant

    Science.gov (United States)

    Stoeser, D. B.; Rickman, D. L.; Wilson, S.

    2010-01-01

    A waste material from an aggregate producing quarry has been used to make an inexpensive lunar simulant called BP-1. The feedstock is the Black Point lava flow in northern Arizona. Although this is part of the San Francisco volcanic field, which is also the source of the JSC-1 series feedstock, BP-1 and JSC-1 are distinct. Chemically, the Black Point flow is an amygdaloidal nepheline-bearing basalt. The amygdules are filled with secondary minerals containing opaline silica, calcium carbonate, and ferric iron minerals. X-ray diffraction (XRD) detected approximately 3% quartz, which is in line with tests done by the Kennedy Space Center Industrial Hygiene Office. Users of this material should use appropriate protective equipment. XRD also showed the presence of significant halite and some bassanite. Both are interpreted to be evaporative residues due to recycling of wash water at the quarry. The size distribution of BP-1 may be superior to some other simulants for some applications.

  19. Evaporative demand, transpiration, and photosynthesis: How are they changing?

    Science.gov (United States)

    Farquhar, G. D.; Roderick, M. L.

    2009-04-01

    in leaves of C3 species. Planta 149: 78-90. Hobbins, MT, Dai, A, Roderick, ML, and Farquhar, GD, 2008: Revisiting the parameterization of potential evaporation as a driver of long-term water balance trends. Geophysical Research Letters. 35, L12403, doi:10.1029/2008GL033840. Roderick, ML, and Farquhar, GD, 2002: The cause of decreased pan evaporation over the last 50 years. Science 298: 1410-1411. Roderick, ML, Rotstayn, LD, Farquhar, GD, and Hobbins, MT, 2007: On the attribution of changing pan evaporation. Geophysical Research Letters VOL. 34, L17403, doi:10.1029/2007GL031166. Rotstayn, LD, Roderick, ML, and Farquhar, GD, 2006: A simple pan-evaporation model for analysis of climate simulations: Evaluation over Australia. Geophysical Research Letters 33: L17715, doi: 10.1029/2006GL027114 Wong, SC, Cowan, IR, and Farquhar, GD, 1979: Stomatal conductance correlates with photosynthetic capacity. Nature 282: 424-426.

  20. Plastics recycling: challenges and opportunities.

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-07-27

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  1. Plastics recycling: challenges and opportunities

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-01-01

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  2. Quantized evaporation from liquid helium

    Science.gov (United States)

    Baird, M. J.; Hope, F. R.; Wyatt, A. F. G.

    1983-07-01

    The atomic-level kinetics of evaporation from a liquid surface are investigated experimentally for the case of liquid He-4. A pulse of phonons was injected by a submerged thin-film heater into purified He-4 (cooled to less than about 0.1 K) and collimated into a beam directed at the liquid surface; the atoms liberated at the surface were detected by a bolometer. The energy of the incident phonon and the kinetic energy of the liberated atom were calculated by determining the group velocity (from the minimum time elapsed between the beginning of the heater pulse and the arrival of the leading edge of the signal) and combining it with neutron-measured excitation dispersion data. Measurements were also made with a mixture of He-3 and He-4. The results are shown to be in good agreement with theoretical predictions of the phonon-induced quantum evaporation of surface atoms: the energy of the phonon is divided between the kinetic energy of the liberated atom and the energy required to overcome the binding forces.

  3. Evaporator modeling - A hybrid approach

    International Nuclear Information System (INIS)

    Ding Xudong; Cai Wenjian; Jia Lei; Wen Changyun

    2009-01-01

    In this paper, a hybrid modeling approach is proposed to model two-phase flow evaporators. The main procedures for hybrid modeling includes: (1) Based on the energy and material balance, and thermodynamic principles to formulate the process fundamental governing equations; (2) Select input/output (I/O) variables responsible to the system performance which can be measured and controlled; (3) Represent those variables existing in the original equations but are not measurable as simple functions of selected I/Os or constants; (4) Obtaining a single equation which can correlate system inputs and outputs; and (5) Identify unknown parameters by linear or nonlinear least-squares methods. The method takes advantages of both physical and empirical modeling approaches and can accurately predict performance in wide operating range and in real-time, which can significantly reduce the computational burden and increase the prediction accuracy. The model is verified with the experimental data taken from a testing system. The testing results show that the proposed model can predict accurately the performance of the real-time operating evaporator with the maximum error of ±8%. The developed models will have wide applications in operational optimization, performance assessment, fault detection and diagnosis

  4. Coal liquefaction with preasphaltene recycle

    Science.gov (United States)

    Weimer, Robert F.; Miller, Robert N.

    1986-01-01

    A coal liquefaction system is disclosed with a novel preasphaltene recycle from a supercritical extraction unit to the slurry mix tank wherein the recycle stream contains at least 90% preasphaltenes (benzene insoluble, pyridine soluble organics) with other residual materials such as unconverted coal and ash. This subject process results in the production of asphaltene materials which can be subjected to hydrotreating to acquire a substitute for No. 6 fuel oil. The preasphaltene-predominant recycle reduces the hydrogen consumption for a process where asphaltene material is being sought.

  5. Wetting and evaporation of binary mixture drops.

    Science.gov (United States)

    Sefiane, Khellil; David, Samuel; Shanahan, Martin E R

    2008-09-11

    Experimental results on the wetting behavior of water, methanol, and binary mixture sessile drops on a smooth, polymer-coated substrate are reported. The wetting behavior of evaporating water/methanol drops was also studied in a water-saturated environment. Drop parameters (contact angle, shape, and volume) were monitored in time. The effects of the initial relative concentrations on subsequent evaporation and wetting dynamics were investigated. Physical mechanisms responsible for the various types of wetting behavior during different stages are proposed and discussed. Competition between evaporation and hydrodynamic flow are evoked. Using an environment saturated with water vapor allowed further exploration of the controlling mechanisms and underlying processes. Wetting stages attributed to differential evaporation of methanol were identified. Methanol, the more volatile component, evaporates predominantly in the initial stage. The data, however, suggest that a small proportion of methanol remained in the drop after the first stage of evaporation. This residual methanol within the drop seems to influence subsequent wetting behavior strongly.

  6. Evaporation thermal anslysis of Swallow-tailed Axial-grooved Heat Pipe

    Science.gov (United States)

    Zhang, Renping

    2018-03-01

    A detailed mathematical model that describes evaporating characteristics through thin liquid film at the evaporator section of swallow-tailed axial-grooved heat pipe was developed. The numerical simulation results about thin film profile, liquid-vapour interface temperature, evaporating rate and heat flux at the evaporating thin film region were given by the current investigation and the effect of superheat on the liquid-vapour interface temperature, evaporating mass rate and heat flux was discussed. Meanwhile, thermal model of the meniscus region at the evaporating section was developed to calculate the rate of heat transfer. The ratio of the heat conduction in the evaporating thin liquid film region and total heat rate were also discussed. It is indicated that the thickness of thin liquid film rises in a nearly linear fashion. The disjoining pressure can be neglected with increasing the liquid film thickness, tends to be negligibly small. The heat transfer rate at the intrinsic meniscus cannot be compared with that of the evaporating liquid film region.

  7. Dynamics of soil water evaporation during soil drying: laboratory experiment and numerical analysis.

    Science.gov (United States)

    Han, Jiangbo; Zhou, Zhifang

    2013-01-01

    Laboratory and numerical experiments were conducted to investigate the evolution of soil water evaporation during a continuous drying event. Simulated soil water contents and temperatures by the calibrated model well reproduced measured values at different depths. Results show that the evaporative drying process could be divided into three stages, beginning with a relatively high evaporation rate during stage 1, followed by a lower rate during transient stage and stage 2, and finally maintaining a very low and constant rate during stage 3. The condensation zone was located immediately below the evaporation zone in the profile. Both peaks of evaporation and condensation rate increased rapidly during stage 1 and transition stage, decreased during stage 2, and maintained constant during stage 3. The width of evaporation zone kept a continuous increase during stages 1 and 2 and maintained a nearly constant value of 0.68 cm during stage 3. When the evaporation zone totally moved into the subsurface, a dry surface layer (DSL) formed above the evaporation zone at the end of stage 2. The width of DSL also presented a continuous increase during stage 2 and kept a constant value of 0.71 cm during stage 3.

  8. Dynamics of Soil Water Evaporation during Soil Drying: Laboratory Experiment and Numerical Analysis

    Science.gov (United States)

    Han, Jiangbo; Zhou, Zhifang

    2013-01-01

    Laboratory and numerical experiments were conducted to investigate the evolution of soil water evaporation during a continuous drying event. Simulated soil water contents and temperatures by the calibrated model well reproduced measured values at different depths. Results show that the evaporative drying process could be divided into three stages, beginning with a relatively high evaporation rate during stage 1, followed by a lower rate during transient stage and stage 2, and finally maintaining a very low and constant rate during stage 3. The condensation zone was located immediately below the evaporation zone in the profile. Both peaks of evaporation and condensation rate increased rapidly during stage 1 and transition stage, decreased during stage 2, and maintained constant during stage 3. The width of evaporation zone kept a continuous increase during stages 1 and 2 and maintained a nearly constant value of 0.68 cm during stage 3. When the evaporation zone totally moved into the subsurface, a dry surface layer (DSL) formed above the evaporation zone at the end of stage 2. The width of DSL also presented a continuous increase during stage 2 and kept a constant value of 0.71 cm during stage 3. PMID:24489492

  9. Evaporation of Arabian light crude oil spilled on sea and on beach sands : influence of solar radiation and wind velocity

    International Nuclear Information System (INIS)

    Bergueiro, J.R.; Marti, A.; Fuertes, A.; Moreno, S.; Guijarro, S.

    1998-01-01

    The evaporation of crude oil resulting from a spill on sea water was studied to develop a simulation model. Evaporation takes place within a complex process of mass and energy transfer. The effects of physical and chemical variables (such as wind velocity and direct and diffused solar radiation) and the environmental conditions of the spillage were also considered. Arabian crude oil was used in the simulation model for crude oil spillage on sea water. An equation for the evaporation process was used to correlate the evaporated fraction of oil as a function of time. The area of spreading was determined as a function of the dominant stage at each moment of spreading. The evaporation of spilled crude oil on beach sand consisting of three different particle sizes was also studied and used for a simulation model for crude oil spillage on a polluted beach. 7 refs., 6 tabs., 10 figs

  10. Sessile Drop Evaporation and Leidenfrost Phenomenon

    OpenAIRE

    A. K. Mozumder; M. R. Ullah; A. Hossain; M. A. Islam

    2010-01-01

    Problem statement: Quenching and cooling are important process in manufacturing industry for controlling the mechanical properties of materials, where evaporation is a vital mode of heat transfer. Approach: This study experimentally investigated the evaporation of sessile drop for four different heated surfaces of Aluminum, Brass, Copper and Mild steel with a combination of four different liquids as Methanol, Ethanol, Water and NaCl solution. The time of evaporation for the droplet on the hot...

  11. Recycling of americium

    International Nuclear Information System (INIS)

    Hagstroem, Ingela

    1999-12-01

    Separation of actinides from spent nuclear fuel is a part of the process of recycling fissile material. Extracting agents for partitioning the high level liquid waste (HLLW) from conventional PUREX reprocessing is studied. The CTH-process is based on three consecutive extraction cycles. In the first cycle protactinium, uranium, neptunium and plutonium are removed by extraction with di-2-ethylhexyl-phosphoric acid (HDEHP) from a 6 M nitric acid HLLW solution. Distribution ratios for actinides, fission products and corrosion products between HLLW and 1 M HDEHP in an aliphatic diluent have been investigated. To avoid addition of chemicals the acidity is reduced by a tributylphosphate (TBP) extraction cycle. The distribution ratios of elements present in HLLW have been measured between 50 % TBP in an aliphatic diluent and synthetic HLLW in range 0.1-6 M nitric acid. In the third extraction cycle americium and curium are extracted. To separate trivalent actinides from lanthanides a method based on selective stripping of the actinides from 1 M HDEHP is proposed. The aqueous phase containing ammonia, diethylenetriaminepentaacetic acid (DTPA) and lactic acid is recycled in a closed loop after reextraction of the actinides into a second organic phase also containing 1 M HDEHP. Distribution ratios for americium and neodymium have been measured at varying DTPA and lactic acid concentrations and at varying pH. Nitrogen-donor reagents have been shown to have a potential to separate trivalent actinides from lanthanides. 2,2':6,2''-terpyridine as extractant follows the CHON-principle and can in synergy with 2-bromodecanoic acid separate americium from europium. Distribution ratios for americium and europium, in the range of 0.02-0.12 M nitric acid, between nitric acid and 0.02 M terpyridine with 1 M 2-bromodecanoic acid in tert-butylbenzene (TBB) was investigated. Comparison with other nitrogen-donor reagents show that increasing lipophilicity of the molecule, by substitution of

  12. Portable brine evaporator unit, process, and system

    Science.gov (United States)

    Hart, Paul John; Miller, Bruce G.; Wincek, Ronald T.; Decker, Glenn E.; Johnson, David K.

    2009-04-07

    The present invention discloses a comprehensive, efficient, and cost effective portable evaporator unit, method, and system for the treatment of brine. The evaporator unit, method, and system require a pretreatment process that removes heavy metals, crude oil, and other contaminates in preparation for the evaporator unit. The pretreatment and the evaporator unit, method, and system process metals and brine at the site where they are generated (the well site). Thus, saving significant money to producers who can avoid present and future increases in transportation costs.

  13. Safety Analysis Of Actinide Recycled Fast Power Reactor

    International Nuclear Information System (INIS)

    Taufik, Mohammad

    2001-01-01

    Simulation for safety analysis of actinide recycled fast power reactor has been performed. The objective is to know reactor response about ULOF and ULOF and UTOP simultaneous accident. From parameter result such reactivity feedback, power, temperature, and cooled flow rate can conclusion that reactor have inherent safety system, which can back to new Equilibrium State

  14. The Three Rs: Reduce, Reuse, Recycle.

    Science.gov (United States)

    Science Activities, 1991

    1991-01-01

    A student hand-out for a recycling unit defines the terms reduce, recycle, and reuse as they relate to solid waste management. Presents the characteristics of recyclable items such as yard wastes, metals, glass, and paper. Lists organizations through which more information about recycling can be obtained. (MCO)

  15. You're a "What"? Recycling Coordinator

    Science.gov (United States)

    Torpey, Elka Maria

    2011-01-01

    Recycling coordinators supervise curbside and dropoff recycling programs for municipal governments or private firms. Today, recycling is mandatory in many communities. And advancements in collection and processing methods have helped to increase the quantity of materials for which the recycling coordinator is responsible. In some communities,…

  16. The Diffusion Effect of MSW Recycling

    Directory of Open Access Journals (Sweden)

    Yi-Tui Chen

    2017-12-01

    Full Text Available The purpose of this paper is to compare the recycling performance for some waste fractions selected including food waste, bulk waste, paper, metal products, plastics/rubber and glass products and then to develop some directions for the future improvements. The priority of each waste fraction for recycling is also analyzed by using an importance-performance analysis. Traditionally, the recycling rate that is calculated by the ratio of waste recycled to waste collected is used as an indicator to measure recycling performance. Due to a large variation among waste fractions in municipal solid waste (MSW, the recycling rate cannot reflect the actual recycling performance. The ceiling of recycling rate for each waste fraction estimated from the diffusion models is incorporated into a model to calculate recycling performance. The results show that (1 the diffusion effect exists significantly for the recycling of most recyclables but no evidence is found to support the diffusion effect for the recycling of food waste and bulk waste; (2 the recycling performance of waste metal products ranks the top, compared to waste paper, waste glass and other waste fractions; (3 furthermore, an importance-performance analysis (IPA is employed to analyze the priority of recycling programs and thus this paper suggests that the recycling of food waste should be seen as the most priority item to recycle.

  17. Analysis of flow maldistribution in fin-and-tube evaporators for residential air-conditioning systems

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl

    superheat by distributing individual channel mass flow rate continuously (perfect control). The compensation method is compared to the use of a larger evaporator in order to study their trade-off in augmenting system performance (cooling capacity and COP). The studies are performed by numerical modeling...... profile across the A-coil evaporator was predicted by means of CFD simulation software STAR-CD 3.26 (2005) and applied in the numerical model. The main reason for the better face split evaporator performance at uniform conditions or when compensating, is that the superheated "weak" zones with low UA...

  18. Technology options for future recycling

    International Nuclear Information System (INIS)

    Kikuchi, T.

    2000-01-01

    It goes without saying that recycling of nuclear material is indispensable, not only for the effective use of valuable resources but also to reduce the debt which we may leave to the next generations. Many developments in advanced reprocessing technologies have been carried out in several countries to deal with the diversification of nuclear fuels. Also technologies derived from reprocessing or other fuel cycle areas have continued to be developed in terms of recycling. Cost effectiveness and waste-free processing are increasingly important factors in the applicable of an alternate recycling policy. This paper introduces an example of the studies in this field, which has been conducted in Japan and considers the establishment of effective recycling methodologies taking into account the uncertainty of future policy. (authors)

  19. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  20. A recycling molecular beam reactor

    International Nuclear Information System (INIS)

    Prada-Silva, G.; Haller, G.L.; Fenn, J.B.

    1974-01-01

    In a Recycling Molecular Beam Reactor, RMBR, a beam of reactant gas molecules is formed from a supersonic free jet. After collision with a target the molecules pass through the vacuum pumps and are returned to the nozzle source. Continuous recycling permits the integration of very small reaction probabilities into measurable conversions which can be analyzed by gas chromatography. Some preliminary experiments have been carried out on the isomerization of cyclopropane

  1. Entropy Budget for Hawking Evaporation

    Directory of Open Access Journals (Sweden)

    Ana Alonso-Serrano

    2017-07-01

    Full Text Available Blackbody radiation, emitted from a furnace and described by a Planck spectrum, contains (on average an entropy of 3 . 9 ± 2 . 5 bits per photon. Since normal physical burning is a unitary process, this amount of entropy is compensated by the same amount of “hidden information” in correlations between the photons. The importance of this result lies in the posterior extension of this argument to the Hawking radiation from black holes, demonstrating that the assumption of unitarity leads to a perfectly reasonable entropy/information budget for the evaporation process. In order to carry out this calculation, we adopt a variant of the “average subsystem” approach, but consider a tripartite pure system that includes the influence of the rest of the universe, and which allows “young” black holes to still have a non-zero entropy; which we identify with the standard Bekenstein entropy.

  2. Organic evaporator steam valve failure

    International Nuclear Information System (INIS)

    Jacobs, R.A.

    1992-01-01

    Defense Waste Processing Facility (DWPF) Technical has requested an analysis of the capacity of the Organic Evaporator (OE) condenser (OEC) be performed to determine its capability in the case where the OE steam flow control valve fails open. Calculations of the OE boilup and the OEC heat transfer coefficient indicate the OEC will have more than enough capacity to remove the heat at maximum OE boilup. In fact, the Salt Cell Vent Condenser (SCVC) should also have sufficient capacity to handle the maximum OE boilup. Therefore, it would require simultaneous loss of OEC and/or SCVC condensing capacity for the steam valve failure to cause high benzene in the Process Vessel Vent System (PVVS)

  3. The impact of non-isothermal soil moisture transport on evaporation fluxes in a maize cropland

    Science.gov (United States)

    Shao, Wei; Coenders-Gerrits, Miriam; Judge, Jasmeet; Zeng, Yijian; Su, Ye

    2018-06-01

    The process of evaporation interacts with the soil, which has various comprehensive mechanisms. Multiphase flow models solve air, vapour, water, and heat transport equations to simulate non-isothermal soil moisture transport of both liquid water and vapor flow, but are only applied in non-vegetated soils. For (sparsely) vegetated soils often energy balance models are used, however these lack the detailed information on non-isothermal soil moisture transport. In this study we coupled a multiphase flow model with a two-layer energy balance model to study the impact of non-isothermal soil moisture transport on evaporation fluxes (i.e., interception, transpiration, and soil evaporation) for vegetated soils. The proposed model was implemented at an experimental agricultural site in Florida, US, covering an entire maize-growing season (67 days). As the crops grew, transpiration and interception became gradually dominated, while the fraction of soil evaporation dropped from 100% to less than 20%. The mechanisms of soil evaporation vary depending on the soil moisture content. After precipitation the soil moisture content increased, exfiltration of the liquid water flow could transport sufficient water to sustain evaporation from soil, and the soil vapor transport was not significant. However, after a sufficient dry-down period, the soil moisture content significantly reduced, and the soil vapour flow significantly contributed to the upward moisture transport in topmost soil. A sensitivity analysis found that the simulations of moisture content and temperature at the soil surface varied substantially when including the advective (i.e., advection and mechanical dispersion) vapour transport in simulation, including the mechanism of advective vapour transport decreased soil evaporation rate under wet condition, while vice versa under dry condition. The results showed that the formulation of advective soil vapor transport in a soil-vegetation-atmosphere transfer continuum can

  4. Heat loss of heat pipelines in insulation moisture conditions with the evaporation

    Directory of Open Access Journals (Sweden)

    Polovnikov Vyacheslav Yu.

    2014-01-01

    Full Text Available Results of numerical simulation of heat and mass transfer in a wet fibroporous material in conditions of evaporation and steam diffusion were obtained. Values of heat and mass fluxes were established. The contribution of evaporation effect to total heat flux and need to consider volume fractions of water and steam into the structure of fibroporous material in calculation of effective thermal conductivity were shown. Nonstationarity of heat and mass transfer in conditions of considered problem can be ignored.

  5. MOX fuel reprocessing and recycling

    International Nuclear Information System (INIS)

    Guillet, J.L.

    1990-01-01

    This paper is devoted to the reprocessing of MOX fuel in UP2-800 plant at La Hague, and to the MOX successive reprocessing and recycling. 1. MOX fuel reprocessing. In a first step, the necessary modifications in UP2-800 to reprocess MOX fuel are set out. Early in the UP2-800 project, actions have been taken to reprocess MOX fuel without penalty. They consist in measures regarding: Dissolution; Radiological shieldings; Nuclear instrumentation; Criticality. 2. Mox successive reprocessing and recycling. The plutonium recycling in the LWR is now a reality and, as said before, the MOX fuel reprocessing is possible in UP2-800 plant at La Hague. The following actions in this field consist in verifying the MOX successive reprocessing and recycling possibilities. After irradiation, the fissile plutonium content of irradiated MOX fuel is decreased and, in this case, the re-use of plutonium in the LWR need an important increase of initial Pu enrichment inconsistent with the Safety reactor constraints. Cogema opted for reprocessing irradiated MOX fuel in dilution with the standard UO2 fuel in appropriate proportions (1 MOX for 4 UO2 fuel for instance) in order to save a fissile plutonium content compatible with MOX successive recycling (at least 3 recyclings) in LWR. (author). 2 figs

  6. Intrinsic Evaporative Cooling by Hygroscopic Earth Materials

    Directory of Open Access Journals (Sweden)

    Alexandra R. Rempel

    2016-08-01

    Full Text Available The phase change of water from liquid to vapor is one of the most energy-intensive physical processes in nature, giving it immense potential for cooling. Diverse evaporative cooling strategies have resulted worldwide, including roof ponds and sprinklers, courtyard fountains, wind catchers with qanats, irrigated green roofs, and fan-assisted evaporative coolers. These methods all require water in bulk liquid form. The evaporation of moisture that has been sorbed from the atmosphere by hygroscopic materials is equally energy-intensive, however, yet has not been examined for its cooling potential. In arid and semi-arid climates, hygroscopic earth buildings occur widely and are known to maintain comfortable indoor temperatures, but evaporation of moisture from their walls and roofs has been regarded as unimportant since water scarcity limits irrigation and rainfall; instead, their cool interiors are attributed to well-established mass effects in delaying the transmission of sensible gains. Here, we investigate the cooling accomplished by daily cycles of moisture sorption and evaporation which, requiring only ambient humidity, we designate as “intrinsic” evaporative cooling. Connecting recent soil science to heat and moisture transport studies in building materials, we use soils, adobe, cob, unfired earth bricks, rammed earth, and limestone to reveal the effects of numerous parameters (temperature and relative humidity, material orientation, thickness, moisture retention properties, vapor diffusion resistance, and liquid transport properties on the magnitude of intrinsic evaporative cooling and the stabilization of indoor relative humidity. We further synthesize these effects into concrete design guidance. Together, these results show that earth buildings in diverse climates have significant potential to cool themselves evaporatively through sorption of moisture from humid night air and evaporation during the following day’s heat. This finding

  7. Mercury recycling in the United States in 2000

    Science.gov (United States)

    Brooks, William E.; Matos, Grecia R.

    2005-01-01

    mercury is estimated because it is a low-volume commodity and its production, use, and disposal is difficult to track. The prices and volumes of each category of mercury-containing material may change dramatically from year to year. For example, the average price of mercury was approximately $150 per flask from 2000 until 2003 and then rose sharply to $650 per flask in fall 2004 and approximately $850 per flask in spring 2005. Since 1927, the common unit for measuring and pricing mercury has been the flask in order to conform to the system used at Almaden, Spain (Meyers, 1951). One flask weighs 34.5 kilograms, and 29 flasks of mercury are contained in a metric ton. In the United States, the chlorine-caustic soda industry, which is the leading end-user of elemental mercury, recycles most of its mercury in-plant as home scrap. Annual purchases of replacement mercury by the chlorine-caustic soda industry indicate that some mercury may be lost through evaporation to the environment, put into a landfill as industrial waste, or trapped within pipes in the plant. Impending closure of domestic and foreign mercury-cell chlorine-caustic soda plants and the shift to nonmercury technology for chlorine-caustic soda production could ultimately result in a significant volume of elemental mercury for recycling, sale, or storage. Globally, mercury is widely used in artisanal, or small-scale, gold mining. Most of that mercury is lost to the environment and is not recycled. The recycling rate for mercury was not available owing to insufficient data in 2000, and the efficiency of mercury recycling was estimated to be 62 percent.

  8. Design of the Advanced Virgo non-degenerate recycling cavities

    International Nuclear Information System (INIS)

    Granata, M; Barsuglia, M; Flaminio, R; Freise, A; Hild, S; Marque, J

    2010-01-01

    Advanced Virgo is the project to upgrade the interferometric gravitational wave detector Virgo, and it foresees the implementation of power and signal non-degenerate recycling cavities. Such cavities suppress the build-up of high order modes of the resonating sidebands, with some advantage for the commissioning of the detector and the build-up of the gravitational signal. Here we present the baseline design of the Advanced Virgo non-degenerate recycling cavities, giving some preliminary results of simulations about the tolerances of this design to astigmatism, mirror figure errors and thermal lensing.

  9. Molecular characterization and volatility evolution of α-pinene ozonolysis SOA during isothermal evaporations

    Science.gov (United States)

    D'Ambro, E.; Schobesberger, S.; Lopez-Hilfiker, F.; Shilling, J. E.; Lee, B. H.; Thornton, J. A.

    2017-12-01

    α-Pinene (C10H16), the most abundantly emitted monoterpene, is a large contributor to global biogenic secondary organic aerosol (SOA) budgets due to its high SOA yields upon oxidation. We probe the volatility and evaporation behavior upon dilution of α-pinene SOA to further our understanding of the nascent volatility distribution, viscosity, and how these evolve in time absent photochemical oxidation. We present molecular composition measurements of the gas and particle phases of α-pinene ozonolysis SOA formed at 0% and 50% relative humidity (RH), followed by room-temperature evaporation in ultra-high purity N2 humidified to 20-90% RH. Experiments were performed in the Pacific Northwest National Laboratory 10.6 m3 and the University of Washington 0.7 m3 environmental chambers utilizing a Filter Inlet for Gases and AEROsols (FIGAERO) coupled to a high-resolution time of flight chemical ionization mass spectrometer utilizing iodide adduct ionization. We present novel insights into the total mass that evaporates as a function of time from 10 min to 24 hours without heating, the molecular speciation of the evaporate, as well as the effective volatility and composition of the SOA mass remaining. Consistent with previous studies, we find two stages of evaporation: a rapid loss of a large portion of the total signal over the course of ≤3 hours, followed by a stage of much slower evaporation over the proceeding 21 hours. Varying the RH of formation effects evaporation rate on timescales ≤3 hours, however the mass fraction remaining after 24 hours converges to 30-50% under all formation and evaporation RHs. We simulate the evaporation behavior and remaining fractions desorbed via temperature programmed thermal desorption to derive effective saturation vapor concentrations, mass accommodation coefficients, and rates of chemical evolution producing both higher and lower volatility components during the evaporation time period.

  10. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    The Combustion Byproducts Recycling Consortium (CBRC) program was developed as a focused program to remove and/or minimize the barriers for effective management of over 123 million tons of coal combustion byproducts (CCBs) annually generated in the USA. At the time of launching the CBRC in 1998, about 25% of CCBs were beneficially utilized while the remaining was disposed in on-site or off-site landfills. During the ten (10) year tenure of CBRC (1998-2008), after a critical review, 52 projects were funded nationwide. By region, the East, Midwest, and West had 21, 18, and 13 projects funded, respectively. Almost all projects were cooperative projects involving industry, government, and academia. The CBRC projects, to a large extent, successfully addressed the problems of large-scale utilization of CCBs. A few projects, such as the two Eastern Region projects that addressed the use of fly ash in foundry applications, might be thought of as a somewhat smaller application in comparison to construction and agricultural uses, but as a novel niche use, they set the stage to draw interest that fly ash substitution for Portland cement might not attract. With consideration of the large increase in flue gas desulfurization (FGD) gypsum in response to EPA regulations, agricultural uses of FGD gypsum hold promise for large-scale uses of a product currently directed to the (currently stagnant) home construction market. Outstanding achievements of the program are: (1) The CBRC successfully enhanced professional expertise in the area of CCBs throughout the nation. The enhanced capacity continues to provide technology and information transfer expertise to industry and regulatory agencies. (2) Several technologies were developed that can be used immediately. These include: (a) Use of CCBs for road base and sub-base applications; (b) full-depth, in situ stabilization of gravel roads or highway/pavement construction recycled materials; and (c) fired bricks containing up to 30%-40% F

  11. Sequence crystallization during isotherm evaporation of southern ...

    African Journals Online (AJOL)

    Southern Algerian's natural brine sampled from chott Baghdad may be a source of mineral salts with a high economic value. These salts are recoverable by simple solar evaporation. Indeed, during isothermal solar evaporation, it is possible to recover mineral salts and to determine the precipitation sequences of different ...

  12. Odors from evaporation of acidified pig urine

    NARCIS (Netherlands)

    Willers, H.C.; Hobbs, P.J.; Ogink, N.W.M.

    2004-01-01

    In the Dutch Hercules project feces and urine from pigs are collected separately underneath the slatted floor in a pig house and treated in two processes. Feces are composted and urine is concentrated by water evaporation in a packed bed. Exhaust air from the pig house is used for the evaporation in

  13. 21 CFR 131.130 - Evaporated milk.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Evaporated milk. 131.130 Section 131.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION MILK AND CREAM Requirements for Specific Standardized Milk and Cream § 131.130 Evaporated milk. (a...

  14. An evaporation based digital microflow meter

    NARCIS (Netherlands)

    Nie, C; Frijns, A J H; Mandamparambil, R; Zevenbergen, M A G; den Toonder, J M J

    2015-01-01

    In this work, we present a digital microflow meter operating in the range 30-250 nl min-1 for water. The principle is based on determining the evaporation rate of the liquid via reading the number of wetted pore array structures in a microfluidic system, through which continuous evaporation takes

  15. An evaporation based digital microflow meter

    NARCIS (Netherlands)

    Nie, C.; Frijns, A.J.H.; Mandamparambil, R.; Zevenbergen, M.A.G.; Toonder, den J.M.J.

    2015-01-01

    In this work, we present a digital microflow meter operating in the range 30–250 nl min-1 for water. The principle is based on determining the evaporation rate of the liquid via reading the number of wetted pore array structures in a microfluidic system, through which continuous evaporation takes

  16. 242-A evaporator vacuum condenser system

    International Nuclear Information System (INIS)

    Smith, V.A.

    1994-01-01

    This document is written for the 242-A evaporator vacuum condenser system (VCS), describing its purpose and operation within the evaporator. The document establishes the operating parameters specifying pressure, temperature, flow rates, interlock safety features and interfacing sub-systems to support its operation

  17. Shadow mask evaporation through monolayer modified nanostencils

    NARCIS (Netherlands)

    Kolbel, M.; Tjerkstra, R.W.; Brugger, J.P.; van Rijn, C.J.M.; Nijdam, W.; Huskens, Jurriaan; Reinhoudt, David

    2002-01-01

    Gradual clogging of the apertures of nanostencils used as miniature shadow masks in metal evaporations can be reduced by coating the stencil with self-assembled monolayers (SAM). This is quantified by the dimensions (height and volume) of gold features obtained by nanostencil evaporation as measured

  18. Floating convection barrier for evaporation source

    International Nuclear Information System (INIS)

    1975-01-01

    A floating matrix of titanium in an uranium evaporation source, melted by an electron beam, serves as a barrier for preventing cooler material from reaching the evaporation area. This construction allows a big volume of melted uranium to be present and new uranium to be furnished in regulated intervals without manual intervention

  19. Structuring of polymer solutions upon solvent evaporation

    NARCIS (Netherlands)

    Schaefer, C.; van der Schoot, P.|info:eu-repo/dai/nl/102140618; Michels, J. J.

    2015-01-01

    The morphology of solution-cast, phase-separated polymers becomes finer with increasing solvent evaporation rate. We address this observation theoretically for a model polymer where demixing is induced by steady solvent evaporation. In contrast to what is the case for a classical, thermal quench

  20. Evaporation experiments and modelling for glass melts

    NARCIS (Netherlands)

    Limpt, J.A.C. van; Beerkens, R.G.C.

    2007-01-01

    A laboratory test facility has been developed to measure evaporation rates of different volatile components from commercial and model glass compositions. In the set-up the furnace atmosphere, temperature level, gas velocity and batch composition are controlled. Evaporation rates have been measured

  1. Performance Analysis of an Evaporator for a Diesel Engine–Organic Rankine Cycle (ORC) Combined System and Influence of Pressure Drop on the Diesel Engine Operating Characteristics

    OpenAIRE

    Chen Bei; Hongguang Zhang; Fubin Yang; Songsong Song; Enhua Wang; Hao Liu; Ying Chang; Hongjin Wang; Kai Yang

    2015-01-01

    The main purpose of this research is to analyze the performance of an evaporator for the organic Rankine cycle (ORC) system and discuss the influence of the evaporator on the operating characteristics of diesel engine. A simulation model of fin-and-tube evaporator of the ORC system is established by using Fluent software. Then, the flow and heat transfer characteristics of the exhaust at the evaporator shell side are obtained, and then the performance of the fin-and-tube evaporator of the ORC...

  2. Process control for a continuous uranyl nitrate evaporator

    International Nuclear Information System (INIS)

    Peterson, S.F.; MacIntyre, L.P.

    1984-07-01

    A continuous uranyl nitrate evaporator at the Savannah River Plant (SRP) in Aiken, South Carolina ws the subject of this work. A rigorous mathematical model of the evaporator was developed. A difference equation form of the model was then constructed and used for control studies. Relative gain analysis was done on the system in order to identify any promising multivariable control schemes. Several alternate control schemes were modeled, tuned, and compared against the scheme presently in use at SRP. As the pneumatic specific gravity instrumentation at SRP is very noisy, the noise was simulated and used in the second phase of the control study. In this phase, alternate tuning methods and filters were invesigated and compared. The control studies showed that the control algorithm now in use at SRP is the simplest and best available. 10 references, 53 figures, 22 tables

  3. Microporous Cokes Formed in Zeolite Catalysts Enable Efficient Solar Evaporation

    KAUST Repository

    Wang, Jianjian

    2017-03-13

    Cokes are inevitably generated during zeolite-catalyzed reactions as deleterious side products that deactivate the catalyst. In this study, we in-situ converted cokes into carbons within the confined microporous zeolite structures and evaluated their performances as absorbing materials for solar-driven water evaporation. With a properly chosen zeolite, the cokederived carbons possessed ordered interconnected pores and tunable compositions. We found that the porous structure and the oxygen content in as-prepared carbons had important influences on their energy conversion efficiencies. Among various investigated carbon materials, the carbon derived from the methanol-to-olefins reaction over zeolite Beta gave the highest conversion efficiency of 72% under simulated sunlight with equivalent solar intensity of 2 suns. This study not only demonstrates the great potential of traditionally useless cokes for solar thermal applications but also provides new insights into the design of carbon-based absorbing materials for efficient solar evaporation.

  4. Evaporation and condensation at a liquid methanol surface

    Science.gov (United States)

    Matsumoto, Mitsuhiro; Yasuoka, Kenji; Kataoka, Yosuke

    1994-07-01

    The dynamics of evaporation and condensation at a flat liquid surface of methanol were studied under the liquidvapor equilibrium condition at room temperature with molecular dynamics computer simulation techniques. Analysis of molecular trajectories shows that the condensation coefficient is 89%. It suggests that only a tenth of incident vapor molecules are reflected at the liquid surface, contrary to a prediction of a classical transition state theory. To investigate the potential barrier of the evaporation-condensation process, a particle insertion method was applied and the local chemical potential near the surface was evaluated. The calculated chemical potential is constant in the whole region including the surface layer and no potential barrier is observed in the vincinity of the surface, which casts strong doubt on the explanation of a transition state theory.

  5. Drop evaporation and triple line dynamics

    Science.gov (United States)

    Sobac, Benjamin; Brutin, David; Gavillet, Jerome; Université de Provence Team; Cea Liten Team

    2011-03-01

    Sessile drop evaporation is a phenomenon commonly came across in nature or in industry with cooling, paintings or DNA mapping. However, the evaporation of a drop deposited on a substrate is not completely understood due to the complexity of the problem. Here we investigate, with several nano-coating of the substrate (PTFE, SiOx, SiOc and CF), the influence of the dynamic of the triple line on the evaporation process. The experiment consists in analyzing simultaneously the motion of the triple line, the kinetics of evaporation, the internal thermal motion and the heat and mass transfer. Measurements of temperature, heat-flux and visualizations with visible and infrared cameras are performed. The dynamics of the evaporative heat flux appears clearly different depending of the motion of the triple line

  6. Water evaporation on highly viscoelastic polymer surfaces.

    Science.gov (United States)

    Pu, Gang; Severtson, Steven J

    2012-07-03

    Results are reported for a study on the evaporation of water droplets from a highly viscoelastic acrylic polymer surface. These are contrasted with those collected for the same measurements carried out on polydimethylsiloxane (PDMS). For PDMS, the evaporation process involves the expected multistep process including constant drop area, constant contact angle, and finally a combination of these steps until the liquid is gone. In contrast, water evaporation from the acrylic polymer shows a constant drop area mode throughout. Furthermore, during the evaporation process, the drop area actually expands on the acrylic polymer. The single mode evaporation process is consistent with formation of wetting structures, which cannot be propagated by the capillary forces. Expansion of the drop area is attributed to the influence of the drop capillary pressure. Furthermore, the rate of drop area expansion is shown to be dependent on the thickness of the polymer film.

  7. Controlling water evaporation through self-assembly.

    Science.gov (United States)

    Roger, Kevin; Liebi, Marianne; Heimdal, Jimmy; Pham, Quoc Dat; Sparr, Emma

    2016-09-13

    Water evaporation concerns all land-living organisms, as ambient air is dryer than their corresponding equilibrium humidity. Contrarily to plants, mammals are covered with a skin that not only hinders evaporation but also maintains its rate at a nearly constant value, independently of air humidity. Here, we show that simple amphiphiles/water systems reproduce this behavior, which suggests a common underlying mechanism originating from responding self-assembly structures. The composition and structure gradients arising from the evaporation process were characterized using optical microscopy, infrared microscopy, and small-angle X-ray scattering. We observed a thin and dry outer phase that responds to changes in air humidity by increasing its thickness as the air becomes dryer, which decreases its permeability to water, thus counterbalancing the increase in the evaporation driving force. This thin and dry outer phase therefore shields the systems from humidity variations. Such a feedback loop achieves a homeostatic regulation of water evaporation.

  8. Modelling refrigerant distribution in microchannel evaporators

    DEFF Research Database (Denmark)

    Brix, Wiebke; Kærn, Martin Ryhl; Elmegaard, Brian

    2009-01-01

    of the refrigerant distribution is carried out for two channels in parallel and for two different cases. In the first case maldistribution of the inlet quality into the channels is considered, and in the second case a non-uniform airflow on the secondary side is considered. In both cases the total mixed superheat...... out of the evaporator is kept constant. It is shown that the cooling capacity of the evaporator is reduced significantly, both in the case of unevenly distributed inlet quality and for the case of non-uniform airflow on the outside of the channels.......The effects of refrigerant maldistribution in parallel evaporator channels on the heat exchanger performance are investigated numerically. For this purpose a 1D steady state model of refrigerant R134a evaporating in a microchannel tube is built and validated against other evaporator models. A study...

  9. Sodium evaporation into a forced argon flow

    International Nuclear Information System (INIS)

    Kumada, Toshiaki; Kasahara, Fumio; Ishiguro, Ryoji

    1975-01-01

    Evaporation from a rectangular sodium free surface into an argon flow was measured. Tests were carried out with varying sodium temperature, argon velocity and argon temperature respectively under conditions of fog formation being possible. In order to clarify the enhancement of evaporation by fog formation, convection heat transfer from a plate of the same geometry into an air flow was also measured. The evaporation rate and Sherwood number were compared with those predicted by both the heat transfer experiment and the theory proposed by Hill and Szekely, and also a comparison was run with the previously reported experimental results of sodium evaporation. As a result it was shown that the sodium evaporation rate in this experiment is at least four times as large as that predicted by the heat transfer experiment and varies almost linearly with the heat transfer rate and the sodium vapour pressure. (auth.)

  10. Recycled concrete with coarse recycled aggregate. An overview and analysis

    Directory of Open Access Journals (Sweden)

    B. González-Fonteboa

    2018-04-01

    Full Text Available The construction field has contributed to environmental degradation, producing a high amount of construction and demolition waste (C&D waste and consuming large volumes of natural resources. In this context, recycled concrete (RC has been recognised as a means to preserve natural resources and reduce space for waste storage. During the last decades, many researchers have developed works studying different recycled concrete properties. This review focuses on structural RC made with coarse recycled aggregate from concrete waste. The main objective is to provide a state of the art report on RC’s properties and an analysis on how to predict them taking into account relevant research works. Moreover, the study tries to collect and update RC findings, proposing equations to define RC’s performance, in terms of mechanical strength, modulus of elasticity, stress-strain, creep and shrinkage.

  11. Evaporational losses under different soil moisture regimes and atmospheric evaporativities using tritium

    International Nuclear Information System (INIS)

    Saxena, P.; Chaudhary, T.N.; Mookerji, P.

    1991-01-01

    Tritium as tracer was used in a laboratory study to estimate the contribution of moisture from different soil depths towards actual soil water evaporation. Results indicated that for comparable amounts of free water evaporation (5 cm), contribution of moisture from 70-80 cm soil layer towards total soil moisture loss through evaporation increased nearly 1.5 to 3 folds for soils with water table at 90 cm than without water table. Identical initial soil moistures were exposed to different atmospheric evaporativities. Similarly, for a given initial soil moisture status, upward movement of moisture from 70-80 cm soil layer under low evaporativity was nearly 8 to 12 times that of under high evaporativity at 5 cm free water evaporation value. (author). 6 refs., 4 tabs., 2 figs

  12. What can recycling in thermal reactors accomplish?

    International Nuclear Information System (INIS)

    Piet, Steven J.; Matthern, Gretchen E.; Jacobson, Jacob J.

    2007-01-01

    Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives. (authors)

  13. What can Recycling in Thermal Reactors Accomplish?

    International Nuclear Information System (INIS)

    Steven Piet; Gretchen E. Matthern; Jacob J. Jacobson

    2007-01-01

    Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives

  14. Auditing an intensive care unit recycling program.

    Science.gov (United States)

    Kubicki, Mark A; McGain, Forbes; O'Shea, Catherine J; Bates, Samantha

    2015-06-01

    The provision of health care has significant direct environmental effects such as energy and water use and waste production, and indirect effects, including manufacturing and transport of drugs and equipment. Recycling of hospital waste is one strategy to reduce waste disposed of as landfill, preserve resources, reduce greenhouse gas emissions, and potentially remain fiscally responsible. We began an intensive care unit recycling program, because a significant proportion of ICU waste was known to be recyclable. To determine the weight and proportion of ICU waste recycled, the proportion of incorrect waste disposal (including infectious waste contamination), the opportunity for further recycling and the financial effects of the recycling program. We weighed all waste and recyclables from an 11-bed ICU in an Australian metropolitan hospital for 7 non-consecutive days. As part of routine care, ICU waste was separated into general, infectious and recycling streams. Recycling streams were paper and cardboard, three plastics streams (polypropylene, mixed plastics and polyvinylchloride [PVC]) and commingled waste (steel, aluminium and some plastics). ICU waste from the waste and recycling bins was sorted into those five recycling streams, general waste and infectious waste. After sorting, the waste was weighed and examined. Recycling was classified as achieved (actual), potential and total. Potential recycling was defined as being acceptable to hospital protocol and local recycling programs. Direct and indirect financial costs, excluding labour, were examined. During the 7-day period, the total ICU waste was 505 kg: general waste, 222 kg (44%); infectious waste, 138 kg (27%); potentially recyclable waste, 145 kg (28%). Of the potentially recyclable waste, 70 kg (49%) was actually recycled (14% of the total ICU waste). In the infectious waste bins, 82% was truly infectious. There was no infectious contamination of the recycling streams. The PVC waste was 37% contaminated

  15. Process evaluation of enzymatic hydrolysis with filtrate recycle for the production of high concentration sugars.

    Science.gov (United States)

    Xue, Ying; Rusli, Jannov; Chang, Hou-Min; Phillips, Richard; Jameel, Hasan

    2012-02-01

    Process simulation and lab trials were carried out to demonstrate and confirm the efficiency of the concept that recycling hydrolysate at low total solid enzymatic hydrolysis is one of the options to increase the sugar concentration without mixing problems. Higher sugar concentration can reduce the capital cost for fermentation and distillation because of smaller retention volume. Meanwhile, operation cost will also decrease for less operating volume and less energy required for distillation. With the computer simulation, time and efforts can be saved to achieve the steady state of recycling process, which is the scenario for industrial production. This paper, to the best of our knowledge, is the first paper discussing steady-state saccharification with recycling of the filtrate form enzymatic hydrolysis to increase sugar concentration. Recycled enzymes in the filtrate (15-30% of the original enzyme loading) resulted in 5-10% higher carbohydrate conversion compared to the case in which recycled enzymes were denatured. The recycled hydrolysate yielded 10% higher carbohydrate conversion compared to pure sugar simulated hydrolysate at the same enzyme loading, which indicated hydrolysis by-products could boost enzymatic hydrolysis. The high sugar concentration (pure sugar simulated) showed inhibition effect, since about 15% decrease in carbohydrate conversion was observed compared with the case with no sugar added. The overall effect of hydrolysate recycling at WinGEMS simulated steady-state conditions with 5% total solids was increasing the sugar concentration from 35 to 141 g/l, while the carbohydrate conversion was 2% higher for recycling at steady state (87%) compared with no recycling strategy (85%). Ten percent and 15% total solid processes were also evaluated in this study.

  16. ASSESSMENT OF ENERGY SAVING IN WASTE RECYCLING USING SYSTEM DYNAMICS

    Directory of Open Access Journals (Sweden)

    Eugênio de Oliveira Simonetto

    2013-06-01

    Full Text Available Recycling is a topic of great importance in integrated waste management, evidence of this is verified in the National Policy of Solid Waste, decreed in 2010, where it is considered one of the priorities. In this article is presented a computer simulation model, since their development until its validation, which aims to support environmental managers in their decisions regarding the definition and / or maintenance of solid waste policies recycling, as well as evaluating the benefits of process in the environment (in this article we evaluated the energy savings. For the model development was considered: the rate of natural population growth (births and deaths, percentage of solid waste recycled (for each type of material, gravimetric composition of the material in the total waste generated, the amount of waste generated per inhabitant and energy savings caused by each distinct type of material. Through the model results generated, end users (environmental managers thereof may, for example, set incentives to reduce the total generation of solid waste, produce campaigns enhancing reuse and recycling and to assess the relative benefits of energy savings caused by recycling. Model validation was through analysis of future scenarios for a given municipality in southern Brazil. For modeling and system validation was used Vensim from Ventana Systems.

  17. Radioactive materials in recycled metals.

    Science.gov (United States)

    Lubenau, J O; Yusko, J G

    1995-04-01

    In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.

  18. A UK perspective on recycling

    International Nuclear Information System (INIS)

    Williams, T.

    1991-01-01

    The United Kingdom, through the recycling of depleted uranium from Magnox reactors into Advanced Gas-cooled Reactor (AGR) fuel, has already recycled significant quantities of reprocessed material in reactors owned by Nuclear Electric plc and Scottish Nuclear Limited. This AGR fuel has been satisfactorily irradiated and discharged over a decade or more, and will be reprocessed in the new Thermal Oxide Reprocessing Plant (THORP), currently under construction in the UK. British Nuclear Fuels plc (BNFL) and the UK Atomic Energy Authority (UKAEA) have also been exploiting the potential of plutonium recycled in mixed oxide (MOX) fuel, which they have been making since 1963. All of the UK nuclear companies are committed to further recycling of Magnox depleted uranium during the 1990s, and it is anticipated that oxide recycling will also become firmly established during the next decade. British Nuclear Fuels and Urenco Ltd, as the providers of fuel cycle services, are developing an infrastructure to close the fuel cycle for oxide nuclear fuel, using both the uranium and plutonium arising from reprocessing. (author)

  19. Recycling of polymers: a review.

    Science.gov (United States)

    Ignatyev, Igor A; Thielemans, Wim; Vander Beke, Bob

    2014-06-01

    Plastics are inexpensive, easy to mold, and lightweight. These and many other advantages make them very promising candidates for commercial applications. In many areas, they have substantially suppressed traditional materials. However, the problem of recycling still is a major challenge. There are both technological and economic issues that restrain the progress in this field. Herein, a state-of-art overview of recycling is provided together with an outlook for the future by using popular polymers such as polyolefins, poly(vinyl chloride), polyurethane, and poly(ethylene terephthalate) as examples. Different types of recycling, primary, secondary, tertiary, quaternary, and biological recycling, are discussed together with related issues, such as compatibilization and cross-linking. There are various projects in the European Union on research and application of these recycling approaches; selected examples are provided in this article. Their progress is mirrored by granted patents, most of which have a very limited scope and narrowly cover certain technologies. Global introduction of waste utilization techniques to the polymer market is currently not fully developed, but has an enormous potential. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Recycling of plastics in Germany

    International Nuclear Information System (INIS)

    Thienen, N. von; Patel, M.

    1999-01-01

    This article deals with the waste management of post-consumer plastics in Germany and its potential to save fossil fuels and reduce CO 2 emissions. Since most experience is available for packaging, the paper first gives an overview of the legislative background and the material flows for this sector. Then recycling and recovery processes for plastics waste from all sectors are assessed in terms of their contribution to energy saving and CO 2 abatement. Practically all the options studied show a better performance than waste treatment in an average incinerator which has been chosen as the reference case. High ecological benefits can be achieved by mechanical recycling if virgin polymers are substituted. The paper then presents different scenarios for managing plastic waste in Germany in 1995: considerable savings can be made by strongly enhancing the efficiency of waste incinerators. Under these conditions the distribution of plastics waste among mechanical recycling, feedstock recycling and energy recovery has a comparatively mall impact on the overall results. The maximum savings amount to 74 PJ of energy, i.e, 9% of the chemical sector energy demand in 1995 and 7.0 Mt CO 2 , representing 13% of the sector's emissions. The assessment does not support a general recommendation of energy recovery due to the large difference between the German average and the best available municipal waste-to-energy facilities and also due to new technological developments in the field of mechanical recycling

  1. Characteristics of a micro-fin evaporator: Theoretical analysis and experimental verification

    Directory of Open Access Journals (Sweden)

    Zheng Hui-Fan

    2013-01-01

    Full Text Available A theoretical analysis and experimental verification on the characteristics of a micro-fin evaporator using R290 and R717 as refrigerants were carried out. The heat capacity and heat transfer coefficient of the micro-fin evaporator were investigated under different water mass flow rate, different refrigerant mass flow rate, and different inner tube diameter of micro-fin evaporator. The simulation results of the heat transfer coefficient are fairly in good agreement with the experimental data. The results show that heat capacity and the heat transfer coefficient of the micro-fin evaporator increase with increasing logarithmic mean temperature difference, the water mass flow rate and the refrigerant mass flow rate. Heat capacity of the micro-fin evaporator for diameter 9.52 mm is higher than that of diameter 7.00 mm with using R290 as refrigerant. Heat capacity of the micro-fin evaporator with using R717 as refrigerant is higher than that of R290 as refrigerant. The results of this study can provide useful guidelines for optimal design and operation of micro-fin evaporator in its present or future applications.

  2. Evaporation Rate of Water as a Function of a Magnetic Field and Field Gradient

    Directory of Open Access Journals (Sweden)

    Peng Shang

    2012-12-01

    Full Text Available The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g, 1 g, 1.56 g and 1.96 g in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air.

  3. Evaporation rate of water as a function of a magnetic field and field gradient.

    Science.gov (United States)

    Guo, Yun-Zhu; Yin, Da-Chuan; Cao, Hui-Ling; Shi, Jian-Yu; Zhang, Chen-Yan; Liu, Yong-Ming; Huang, Huan-Huan; Liu, Yue; Wang, Yan; Guo, Wei-Hong; Qian, Ai-Rong; Shang, Peng

    2012-12-11

    The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g), 1 g, 1.56 g and 1.96 g) in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air.

  4. Evaporation Rate of Water as a Function of a Magnetic Field and Field Gradient

    Science.gov (United States)

    Guo, Yun-Zhu; Yin, Da-Chuan; Cao, Hui-Ling; Shi, Jian-Yu; Zhang, Chen-Yan; Liu, Yong-Ming; Huang, Huan-Huan; Liu, Yue; Wang, Yan; Guo, Wei-Hong; Qian, Ai-Rong; Shang, Peng

    2012-01-01

    The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g), 1 g, 1.56 g and 1.96 g) in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air. PMID:23443127

  5. Methadone Recycling Sustains Drug Reservoir in Tissue.

    Science.gov (United States)

    Linares, Oscar A; Fudin, Jeffrey; Daly, Annemarie; Schiesser, William E; Boston, Raymond C

    2015-09-01

    We hypothesize that there is a tissue store of methadone content in humans that is not directly accessible, but is quantifiable. Further, we hypothesize the mechanism by which methadone content is sustained in tissue stores involves methadone uptake, storage, and release from tissue depots in the body (recycling). Accordingly, we hypothesize that such tissue stores, in part, determine plasma methadone levels. We studied a random sample of six opioid-naïve healthy subjects. We performed a clinical trial simulation in silico using pharmacokinetic modeling. We found a large tissue store of methadone content whose size was much larger than methadone's size in plasma in response to a single oral dose of methadone 10 mg. The tissue store measured 13-17 mg. This finding could only be explained by the contemporaneous storage of methadone in tissue with dose recycling. We found that methadone recycles 2-5 times through an inaccessible extravascular compartment (IAC), from an accessible plasma-containing compartment (AC), before exiting irreversibly. We estimate the rate of accumulation (or storage) of methadone in tissue was 0.029-7.29 mg/h. We predict 39 ± 13% to 83 ± 6% of methadone's tissue stores "spillover" into the circulation. Our results indicate that there exists a large quantifiable tissue store of methadone in humans. Our results support the notion that methadone in humans undergoes tissue uptake, storage, release into the circulation, reuptake from the circulation, and re-release into the circulation, and that spillover of methadone from tissue stores, in part, maintain plasma methadone levels in humans.

  6. The evaporation of the charged and uncharged water drops

    Indian Academy of Sciences (India)

    Drop evaporation; ventilation coefficient; evaporation-effect of electrical forces. ... to study the effect of ventilation on the rate of evaporation of the millimeter sized ... a ventilated drop to reach its equilibrium temperature increases with the drop ...

  7. Nuclear recycling: costs, savings, and safeguards

    International Nuclear Information System (INIS)

    Spinrad, B.I.

    1985-01-01

    This chapter discusses the economics, physical and chemical processes, and safety of nuclear fuel recycling. The spent fuel must be chemically reprocessed in order to recover uranium and plutonium. Topics considered include indifference costs, recycling in light water reactors (LWRs), plutonium in fast reactors, the choice between recycling and storage, safeguards, and weapons proliferation. It is shown that the economics of recycling nuclear fuel involves the actual costs and savings of the recycling operation in terms of money spent, made, and saved, and the impact of the recycling on the future cost of uranium

  8. Evaporation of nanofluid droplet on heated surface

    Directory of Open Access Journals (Sweden)

    Yeung Chan Kim

    2015-04-01

    Full Text Available In this study, an experiment on the evaporation of nanofluid sessile droplet on a heated surface was conducted. A nanofluid of 0.5% volumetric concentration mixed with 80-nm-sized CuO powder and pure water were used for experiment. Droplet was applied to the heated surface, and images of the evaporation process were obtained. The recorded images were analyzed to find the volume, diameter, and contact angle of the droplet. In addition, the evaporative heat transfer coefficient was calculated from experimental result. The results of this study are summarized as follows: the base diameter of the droplet was maintained stably during the evaporation. The measured temperature of the droplet was increased rapidly for a very short time, then maintained constantly. The nanofluid droplet was evaporated faster than the pure water droplet under the experimental conditions of the same initial volume and temperature, and the average evaporative heat transfer coefficient of the nanofluid droplet was higher than that of pure water. We can consider the effects of the initial contact angle and thermal conductivity of nanofluid as the reason for this experimental result. However, the effect of surface roughness on the evaporative heat transfer of nanofluid droplet appeared unclear.

  9. 242-A evaporator safety analysis report

    International Nuclear Information System (INIS)

    CAMPBELL, T.A.

    1999-01-01

    This report provides a revised safety analysis for the upgraded 242-A Evaporator (the Evaporator). This safety analysis report (SAR) supports the operation of the Evaporator following life extension upgrades and other facility and operations upgrades (e.g., Project B-534) that were undertaken to enhance the capabilities of the Evaporator. The Evaporator has been classified as a moderate-hazard facility (Johnson 1990). The information contained in this SAR is based on information provided by 242-A Evaporator Operations, Westinghouse Hanford Company, site maintenance and operations contractor from June 1987 to October 1996, and the existing operating contractor, Waste Management Hanford (WMH) policies. Where appropriate, a discussion address the US Department of Energy (DOE) Orders applicable to a topic is provided. Operation of the facility will be compared to the operating contractor procedures using appropriate audits and appraisals. The following subsections provide introductory and background information, including a general description of the Evaporator facility and process, a description of the scope of this SAR revision,a nd a description of the basic changes made to the original SAR

  10. 242-A evaporator safety analysis report

    Energy Technology Data Exchange (ETDEWEB)

    CAMPBELL, T.A.

    1999-05-17

    This report provides a revised safety analysis for the upgraded 242-A Evaporator (the Evaporator). This safety analysis report (SAR) supports the operation of the Evaporator following life extension upgrades and other facility and operations upgrades (e.g., Project B-534) that were undertaken to enhance the capabilities of the Evaporator. The Evaporator has been classified as a moderate-hazard facility (Johnson 1990). The information contained in this SAR is based on information provided by 242-A Evaporator Operations, Westinghouse Hanford Company, site maintenance and operations contractor from June 1987 to October 1996, and the existing operating contractor, Waste Management Hanford (WMH) policies. Where appropriate, a discussion address the US Department of Energy (DOE) Orders applicable to a topic is provided. Operation of the facility will be compared to the operating contractor procedures using appropriate audits and appraisals. The following subsections provide introductory and background information, including a general description of the Evaporator facility and process, a description of the scope of this SAR revision,a nd a description of the basic changes made to the original SAR.

  11. UREP: gateway to uranium recycling

    International Nuclear Information System (INIS)

    Rougeau, J.P.; Durret, L.F.

    1988-01-01

    The industrial experience accumulated in France on recycling makes their conversion service fully reliable technically and economically. Problems associated with chemical and radiochemical behavior have been solved satisfactorily in order to offer customers flexible options for their personal optimization. Economically, a price reduction by a significant factor (up to two) has been proposed by UREP as a firm commitment for the coming years. This is the result of technical experience coupled with favorable scaling effect for the large conversion plant proposed. It is believed that such a positive approach greatly helps customers in managing recycling of their material and generating savings in their fuel cycle economics. This flow of recycled uranium, on top of the 40000 t of natural uranium consumed each year, is a valuable asset available to those utilities which have selected the reprocessing route. 2 figs

  12. Metallic mercury recycling. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Beck, M.A.

    1994-07-01

    Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made.

  13. Radioactive contamination of recycled metals

    International Nuclear Information System (INIS)

    Lubenau, J.O.; Cool, D.A.; Yusko, J.G.

    1996-01-01

    Radioactive sources commingled with metal scrap have become a major problem for the metals recycling industry worldwide. Worldwide there have been 38 confirmed reports of radioactive sources accidentally smelted with recycled metal. In some instances, contaminated metal products were subsequently distributed. The metal mills, their products and byproducts from the metal making process such as slags, crosses and dusts from furnaces can become contaminated. In the U.S., imported ferrous metal products such as reinforcement bars, pipe flanges, table legs and fencing components have been found contaminated with taco. U.S. steel mills have unintentionally smelted radioactive sources on 16 occasions. The resulting cost for decontamination waste disposal and temporary closure of the steel mill is typically USD 10,000,000 and has been as much as USD 23,000,000. Other metal recycling industries that have been affected by this problem include aluminum, copper, zinc, gold, lead and vanadium. (author)

  14. Metallic mercury recycling. Final report

    International Nuclear Information System (INIS)

    Beck, M.A.

    1994-01-01

    Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made

  15. Wetting and evaporation of salt-water nanodroplets: A molecular dynamics investigation.

    Science.gov (United States)

    Zhang, Jun; Borg, Matthew K; Sefiane, Khellil; Reese, Jason M

    2015-11-01

    We employ molecular dynamics simulations to study the wetting and evaporation of salt-water nanodroplets on platinum surfaces. Our results show that the contact angle of the droplets increases with the salt concentration. To verify this, a second simulation system of a thin salt-water film on a platinum surface is used to calculate the various surface tensions. We find that both the solid-liquid and liquid-vapor surface tensions increase with salt concentration and as a result these cause an increase in the contact angle. However, the evaporation rate of salt-water droplets decreases as the salt concentration increases, due to the hydration of salt ions. When the water molecules have all evaporated from the droplet, two forms of salt crystals are deposited, clump and ringlike, depending on the solid-liquid interaction strength and the evaporation rate. To form salt crystals in a ring, it is crucial that there is a pinned stage in the evaporation process, during which salt ions can move from the center to the rim of the droplets. With a stronger solid-liquid interaction strength, a slower evaporation rate, and a higher salt concentration, a complete salt crystal ring can be deposited on the surface.

  16. Theory of evapotranspiration. 2. Soil and intercepted water evaporation

    OpenAIRE

    Budagovskyi, Anatolij Ivanovič; Novák, Viliam

    2011-01-01

    Evaporation of water from the soil is described and quantified. Formation of the soil dry surface layer is quantitatively described, as a process resulting from the difference between the evaporation and upward soil water flux to the soil evaporating level. The results of evaporation analysis are generalized even for the case of water evaporation from the soil under canopy and interaction between evaporation rate and canopy transpiration is accounted for. Relationships describing evapotranspi...

  17. Low-temperature field evaporation of Nb3Sn compound

    International Nuclear Information System (INIS)

    Ksenofontov, V.A.; Kul'ko, V.B.; Kutsenko, P.A.

    1986-01-01

    Investigation results on field evaporation of superconducting Nb 3 Sn compound wth A15 lattice are presented. Compound evaporation is shown to proceed in two stages. Evaporation field and ionic composition of evaporating material are determined. It is found out that in strong electric fields compound surface represents niobium skeleton, wich does not form regular image. Comparison of ion-microscopic and calculated images formed by low-temperature field evaporation indicates to possibility of sample surface reconstruction after preferable tin evaporation

  18. Enhanced Evaporation and Condensation in Tubes

    Science.gov (United States)

    Honda, Hiroshi

    A state-of-the-art review of enhanced evaporation and condensation in horizontal microfin tubes and micro-channels that are used for air-conditioning and refrigeration applications is presented. The review covers the effects of flow pattern and geometrical parameters of the tubes on the heat transfer performance. Attention is paid to the effect of surface tension which leads to enhanced evaporation and condensation in the microfin tubes and micro-channels. A review of prior efforts to develop empirical correlations of the heat transfer coefficient and theoretical models for evaporation and condensation in the horizontal microfin tubes and micro-channels is also presented.

  19. Towards a rational definition of potential evaporation

    Directory of Open Access Journals (Sweden)

    J.-P. Lhommel

    1997-01-01

    Full Text Available The concept of potential evaporation is defined on the basis of the following criteria: (i it must establish an upper limit to the evaporation process in a given environment (the term 'environment' including meteorological and surface conditions, and (ii this upper limit must be readily calculated from measured input data. It is shown that this upper limit is perfectly defined and is given by the Penman equation, applied with the corresponding meteorological data (incoming radiation and air characteristics measured at a reference height and the appropriate surface characteristics (albedo, roughness length, soil heat flux. Since each surface has its own potential evaporation, a function of its own surface characteristics, it is useful to define a reference potential evaporation as a short green grass completely shading the ground. Although the potential evaporation from a given surface is readily calculated from the Penman equation, its physical significance or interpretation is not so straightforward, because it represents only an idealized situation, not a real one. Potential evaporation is the evaporation from this surface, when saturated and extensive enough to obviate any effect of local advection, under the same meteorological conditions. Due to the feedback effects of evaporation on air characteristics, it does not represent the 'real' evaporation (i.e. the evaporation which could be physically observed in the real world from such an extensive saturated surface in these given meteorological conditions (if this saturated surface were substituted for an unsaturated one previously existing. From a rigorous standpoint, this calculated potential evaporation is not physically observable. Nevertheless, an approximate representation can be given by the evaporation from a limited saturated area, the dimension of which depends on the height of measurement of the air characteristics used as input in the Penman equation. If they are taken at a height

  20. Thermocapillary flow about an evaporating meniscus

    Science.gov (United States)

    Schmidt, G. R.; Chung, T. J.

    1992-01-01

    The steady motion and thermal behavior of an evaporating superheated liquid in a small cavity bounded by isothermal sidewalls is examined. Scaling analyses and a two-dimensional finite element model are used to investigate the influence of thermocapillarity, buoyancy, and temperature-dependent mass flux on flowfield, interfacial heat transfer, and meniscus morphology. Numerical investigations indicate the existence of two counter-rotating cells symmetric about the cavity center. Results also show that evaporation tends to counteract this circulation by directing flow toward the hotter sidewalls. Although thermocapillarity and evaporation yield different flowfield distributions, both effects tend to increase interfacial temperature and heat transfer.

  1. Optimized evaporative cooling for sodium Bose-Einstein condensation against three-body loss

    International Nuclear Information System (INIS)

    Shobu, Takahiko; Yamaoka, Hironobu; Imai, Hiromitsu; Morinaga, Atsuo; Yamashita, Makoto

    2011-01-01

    We report on a highly efficient evaporative cooling optimized experimentally. We successfully created sodium Bose-Einstein condensates with 6.4x10 7 atoms starting from 6.6x10 9 thermal atoms trapped in a magnetic trap by employing a fast linear sweep of radio frequency at the final stage of evaporative cooling so as to overcome the serious three-body losses. The experimental results such as the cooling trajectory and the condensate growth quantitatively agree with the numerical simulations of evaporative cooling on the basis of the kinetic theory of a Bose gas carefully taking into account our specific experimental conditions. We further discuss theoretically a possibility of producing large condensates, more than 10 8 sodium atoms, by simply increasing the number of initial thermal trapped atoms and the corresponding optimization of evaporative cooling.

  2. [Interlaboratory Study on Evaporation Residue Test for Food Contact Products (Report 1)].

    Science.gov (United States)

    Ohno, Hiroyuki; Mutsuga, Motoh; Abe, Tomoyuki; Abe, Yutaka; Amano, Homare; Ishihara, Kinuyo; Ohsaka, Ikue; Ohno, Haruka; Ohno, Yuichiro; Ozaki, Asako; Kakihara, Yoshiteru; Kobayashi, Hisashi; Sakuragi, Hiroshi; Shibata, Hiroshi; Shirono, Katsuhiro; Sekido, Haruko; Takasaka, Noriko; Takenaka, Yu; Tajima, Yoshiyasu; Tanaka, Aoi; Tanaka, Hideyuki; Tonooka, Hiroyuki; Nakanishi, Toru; Nomura, Chie; Haneishi, Nahoko; Hayakawa, Masato; Miura, Toshihiko; Yamaguchi, Miku; Watanabe, Kazunari; Sato, Kyoko

    2018-01-01

    An interlaboratory study was performed to evaluate the equivalence between an official method and a modified method of evaporation residue test using three food-simulating solvents (water, 4% acetic acid and 20% ethanol), based on the Japanese Food Sanitation Law for food contact products. Twenty-three laboratories participated, and tested the evaporation residues of nine test solutions as blind duplicates. For evaporation, a water bath was used in the official method, and a hot plate in the modified method. In most laboratories, the test solutions were heated until just prior to evaporation to dryness, and then allowed to dry under residual heat. Statistical analysis revealed that there was no significant difference between the two methods, regardless of the heating equipment used. Accordingly, the modified method provides performance equal to the official method, and is available as an alternative method.

  3. The recycling of reprocessed uranium

    International Nuclear Information System (INIS)

    Lannegrace, J.-P.

    1991-01-01

    The 1990 update to the Uranium Institute's report ''Uranium Market Issues'', presented to this Symposium last year (1990) stated that the impact of recycled reprocessing products on uranium demand would be limited in the near future to that due to MOX fuel fabrication. The report stated that the recycling of reprocessed uranium was still at an early discussion stage, rather than being a short-term prospect. This paper will set out to challenge this assertion, on the basis both of facts and of economic and environmental incentives. (author)

  4. Collection of Recyclables from Cubes

    DEFF Research Database (Denmark)

    Wøhlk, Sanne; Bogh, Morten Bie; Mikkelsen, Hardy

    2014-01-01

    Collection of recyclable materials is a major part of reverse logistics and an important issue in sustainable logistics. In this paper we consider a case study where paper and glass are collected from recycling cubes and transported to a treatment facility where it is processed for reuse. We...... analyze how outsourcing the planning and transportation of the service can result in conflicts of interest and as a consequence cause unsustainable solutions. Finally, we suggest an alternative payment structure which can lead to a common goal, overall economic sustainability, and an improved financial...

  5. Waste collection systems for recyclables

    DEFF Research Database (Denmark)

    Larsen, Anna Warberg; Merrild, Hanna Kristina; Møller, Jacob

    2010-01-01

    and technical limitations are respected, and what will the environmental and economic consequences be? This was investigated in a case study of a municipal waste management system. Five scenarios with alternative collection systems for recyclables (paper, glass, metal and plastic packaging) were assessed...... and treatment of waste were reduced with increasing recycling, mainly because the high cost for incineration was avoided. However, solutions for mitigation of air pollution caused by increased collection and transport should be sought. (C) 2009 Elsevier Ltd. All rights reserved....

  6. Process to recycle shredder residue

    Science.gov (United States)

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

    2001-01-01

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  7. Recycling and surplus chemical programs

    International Nuclear Information System (INIS)

    Harper, T.J.

    1993-05-01

    In 1988, 45 years of defense production came to a close at the US Department of Energy (DOE) Hanford Site. The mission of the Hanford Site was formally changed to environmental restoration and remediation. Westinghouse Hanford Company (WHC) is the management and operations (M ampersand O) contractor leading the cleanup. Within the framework of future Site cleanup, Hanford recycling and surplus chemical programs are making a viable contribution today to waste minimization, diversion of materials from the waste stream, and setting a standard for future operations. This paper focuses on two successful efforts: paper recycling and surplus chemical sales

  8. 1998 interim 242-A Evaporator tank system integrity assessment report

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, C.E.

    1998-07-02

    This Integrity Assessment Report (IAR) is prepared by Fluor Daniel Northwest (FDNW) under contract to Lockheed-Martin Hanford Company (LMHC) for Waste Management Hanford (WMH), the 242-A Evaporator (facility) operations contractor for Fluor Daniel Hanford, and the US Department of Energy, the system owner. The contract specifies that FDNW perform an interim (5 year) integrity assessment of the facility and prepare a written IAR in accordance with Washington Administrative Code (WAC) 173-303-640. The WAC 173-303 defines a treatment, storage, or disposal (TSD) facility tank system as the ``dangerous waste storage or treatment tank and its ancillary equipment and containment.`` This integrity assessment evaluates the two tank systems at the facility: the evaporator vessel, C-A-1 (also called the vapor-liquid separator), and the condensate collection tank, TK-C-100. This IAR evaluates the 242-A facility tank systems up to, but not including, the last valve or flanged connection inside the facility perimeter. The initial integrity assessment performed on the facility evaluated certain subsystems not directly in contact with dangerous waste, such as the steam condensate and used raw water subsystems, to provide technical information. These subsystems were not evaluated in this IAR. The last major upgrade to the facility was project B-534. The facility modifications, as a result of project B-534, were evaluated in the 1993 facility interim integrity assessment. Since that time, the following upgrades have occurred in the facility: installation of a process condensate recycle system, and installation of a package steam boiler to provide steam for the facility. The package boiler is not within the scope of the facility TSD.

  9. 1998 interim 242-A Evaporator tank system integrity assessment report

    International Nuclear Information System (INIS)

    Jensen, C.E.

    1998-01-01

    This Integrity Assessment Report (IAR) is prepared by Fluor Daniel Northwest (FDNW) under contract to Lockheed-Martin Hanford Company (LMHC) for Waste Management Hanford (WMH), the 242-A Evaporator (facility) operations contractor for Fluor Daniel Hanford, and the US Department of Energy, the system owner. The contract specifies that FDNW perform an interim (5 year) integrity assessment of the facility and prepare a written IAR in accordance with Washington Administrative Code (WAC) 173-303-640. The WAC 173-303 defines a treatment, storage, or disposal (TSD) facility tank system as the ''dangerous waste storage or treatment tank and its ancillary equipment and containment.'' This integrity assessment evaluates the two tank systems at the facility: the evaporator vessel, C-A-1 (also called the vapor-liquid separator), and the condensate collection tank, TK-C-100. This IAR evaluates the 242-A facility tank systems up to, but not including, the last valve or flanged connection inside the facility perimeter. The initial integrity assessment performed on the facility evaluated certain subsystems not directly in contact with dangerous waste, such as the steam condensate and used raw water subsystems, to provide technical information. These subsystems were not evaluated in this IAR. The last major upgrade to the facility was project B-534. The facility modifications, as a result of project B-534, were evaluated in the 1993 facility interim integrity assessment. Since that time, the following upgrades have occurred in the facility: installation of a process condensate recycle system, and installation of a package steam boiler to provide steam for the facility. The package boiler is not within the scope of the facility TSD

  10. A Guide to Running a Recycling Project. [Includes Recycling Handbook].

    Science.gov (United States)

    Oregon Recycling Information and Organizing Network, Portland.

    This guide, designed for both students and adults, is intended for individuals who feel they might be interested in establishing a recycling depot. The guide includes such pertinent information as deciding how to set up a depot, markets and transportation, preparation of materials, where to place the depot and when to operate it, publicity and…

  11. The Recycling Solution: How I Increased Recycling on Dilworth Road

    Science.gov (United States)

    Keller, J. Jacob

    2010-01-01

    The grandson of Fred Keller, one of the founders of behavior analysis, Jacob was 10 years old when he conducted the project for his elementary school science fair. We recently contacted Jacob to learn more about his project. He told us the inspiration came from a class field trip to the county recycling center, which included seeing video footage…

  12. Effects of Surface Dipole Lengths on Evaporation of Tiny Water Aggregation

    International Nuclear Information System (INIS)

    Wang Shen; Wan Rongzheng; Fang Haiping; Tu Yusong

    2013-01-01

    Using molecular dynamics simulation, we compared evaporation behavior of a tiny amount of water molecules adsorbed on solid surfaces with different dipole lengths, including surface dipole lengths of 1 fold, 2 folds, 4 folds, 6 folds and 8 folds of 0.14 nm and different charges from 0.1e to 0.9e. Surfaces with short dipole lengths (1-fold system) can always maintain hydrophobic character and the evaporation speeds are not influenced, whether the surface charges are enhanced or weakened; but when surface dipole lengths get to 8 folds, surfaces become more hydrophilic as the surface charge increases, and the evaporation speeds increase gradually and monotonically. By tuning dipole lengths from 1-fold to 8-fold systems, we confirmed non-monotonic variation of the evaporation flux (first increases, then decreases) in 4 fold system with charges (0.1e–0.7e), reported in our previous paper [S. Wang, et al., J. Phys. Chem. B 116 (2012) 13863], and also show the process from the enhancement of this unexpected non-monotonic variation to its vanishment with surface dipole lengths increasing. Herein, we demonstrated two key factors to influence the evaporation flux of a tiny amount of water molecules adsorbed on solid surfaces: the exposed surficial area of water aggregation from where the water molecules can evaporate directly and the attraction potential from the substrate hindering the evaporation. In addition, more interestingly, we showed extra steric effect of surface dipoles on further increase of evaporation flux for 2-folds, 4-folds, 6-folds and 8-folds systems with charges around larger than 0.7e. (The steric effect is first reported by parts of our authors [C. Wang, et al., Sci. Rep. 2 (2012) 358]). This study presents a complete physical picture of the influence of surface dipole lengths on the evaporation behavior of the adsorbed tiny amount of water. (condensed matter: structural, mechanical, and thermal properties)

  13. Simulation

    DEFF Research Database (Denmark)

    Gould, Derek A; Chalmers, Nicholas; Johnson, Sheena J

    2012-01-01

    Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable p...... performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used....

  14. Contact angle change during evaporation of near-critical liquids

    Science.gov (United States)

    Nikolayev, Vadim; Hegseth, John; Beysens, Daniel

    1998-11-01

    An unexpected change of the dynamic contact angle was recently observed in a near-critical liquid-gas system in a space experiment. While the near-critical liquid completely wets a solid under equilibrium conditions, the apparent contact angle changed from 0^circ to about 120^circ during evaporation. We propose an explanation for this phenomenon by taking into account vapor recoil due to evaporation (motion of the vapor from the free liquid surface). This force is normal to the vapor-liquid interface and is directed towards the liquid. It increases sharply near the triple contact line. Near the critical point, where the surface tension force is very weak, the vapor recoil force can be important enough to change the apparent contact angle. A similar effect can also explain the drying of a heater during boiling at high heat flux. The drying greatly reduces the heat transfer to the liquid causing the heater to melt. This phenomenon is called ``boiling crisis", ``burnout" or ``Departure from Nuclear Boiling". We report the preliminary results of the numerical simulation of the liquid evaporation by the Boundary Element method.

  15. Evaporation channel as a tool to study fission dynamics

    Science.gov (United States)

    Di Nitto, A.; Vardaci, E.; La Rana, G.; Nadtochy, P. N.; Prete, G.

    2018-03-01

    The dynamics of the fission process is expected to affect the evaporation residue cross section because of the fission hindrance due to the nuclear viscosity. Systems of intermediate fissility constitute a suitable environment for testing such hypothesis since they are characterized by evaporation residue cross sections comparable or larger than the fission ones. Observables related to emitted charged particles, due to their relatively high emission probability, can be used to put stringent constraints on models describing the excited nucleus decay and to recognize the effects of fission dynamics. In this work model simulations are compared with the experimental data collected via the 32S +100 Mo reaction at Elab = 200 MeV. Consequently we pointed out, exploring an extended set of evaporation channel observables, the limits of the statistical model and the large improvement obtained with a dynamical model. Moreover we stress the importance of using an apparatus covering a large fraction of 4π to extract observables. Finally, we discuss the opportunity to measure more sensitive observables by a new detection device in operation at LNL.

  16. Multi-material classification of dry recyclables from municipal solid waste based on thermal imaging.

    Science.gov (United States)

    Gundupalli, Sathish Paulraj; Hait, Subrata; Thakur, Atul

    2017-12-01

    There has been a significant rise in municipal solid waste (MSW) generation in the last few decades due to rapid urbanization and industrialization. Due to the lack of source segregation practice, a need for automated segregation of recyclables from MSW exists in the developing countries. This paper reports a thermal imaging based system for classifying useful recyclables from simulated MSW sample. Experimental results have demonstrated the possibility to use thermal imaging technique for classification and a robotic system for sorting of recyclables in a single process step. The reported classification system yields an accuracy in the range of 85-96% and is comparable with the existing single-material recyclable classification techniques. We believe that the reported thermal imaging based system can emerge as a viable and inexpensive large-scale classification-cum-sorting technology in recycling plants for processing MSW in developing countries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Experimental and numerical study of an evaporatively-cooled condenser of air-conditioning systems

    International Nuclear Information System (INIS)

    Islam, M.R.; Jahangeer, K.A.; Chua, K.J.

    2015-01-01

    The performance of an air-conditioning unit with evaporately-cooled condenser coil is studied experimentally and numerically. An experimental setup is fabricated by retrofitting a commercially available air-conditioning unit and installing comprehensive measuring sensors and controllers. Experimental result shows that the COP (Coefficient of Performance) of the evaporately-cooled air-conditioning unit increases by about 28% compared to the conventional air cooled air-conditioning unit. To analyze the heat and mass transfer processes involved in the evaporately-cooled condenser, a detailed theoretical model has been developed based on the fluid flow characteristics of the falling film and the thermodynamic aspect of the evaporation process. Simulated results agree well with experimental data. The numerical model provides new insights into the intrinsic links between operating variables and heat transfer characteristics of water film in evaluating the performance of evaporatively-cooled condenser system. Two heat transfer coefficients, namely, wall to bulk and bulk to interface are introduced and computed from the simulation results under different operating conditions. Finally, the overall heat transfer coefficient for the water film is computed and presented as a function of dimensionless variables which can conveniently be employed by engineers to design and analyze high performance evaporatively-cooled heat exchangers. - Highlights: • Performance of evaporatively-cooled condenser is investigated. • Local convective heat transfer coefficients of water film are determined. • Thermal resistance of water film is negligible. • Heat transfer with evaporated vapor plays significant role on performance. • Better condenser performance translates to an improvement in COP

  18. Morphological Evolution of Block Copolymer Particles: Effect of Solvent Evaporation Rate on Particle Shape and Morphology.

    Science.gov (United States)

    Shin, Jae Man; Kim, YongJoo; Yun, Hongseok; Yi, Gi-Ra; Kim, Bumjoon J

    2017-02-28

    Shape and morphology of polymeric particles are of great importance in controlling their optical properties or self-assembly into unusual superstructures. Confinement of block copolymers (BCPs) in evaporative emulsions affords particles with diverse structures, including prolate ellipsoids, onion-like spheres, oblate ellipsoids, and others. Herein, we report that the evaporation rate of solvent from emulsions encapsulating symmetric polystyrene-b-polybutadiene (PS-b-PB) determines the shape and internal nanostructure of micron-sized BCP particles. A distinct morphological transition from the ellipsoids with striped lamellae to the onion-like spheres was observed with decreasing evaporation rate. Experiments and dissipative particle dynamics (DPD) simulations showed that the evaporation rate affected the organization of BCPs at the particle surface, which determined the final shape and internal nanostructure of the particles. Differences in the solvent diffusion rates in PS and PB at rapid evaporation rates induced alignment of both domains perpendicular to the particle surface, resulting in ellipsoids with axial lamellar stripes. Slower evaporation rates provided sufficient time for BCP organization into onion-like structures with PB as the outermost layer, owing to the preferential interaction of PB with the surroundings. BCP molecular weight was found to influence the critical evaporation rate corresponding to the morphological transition from ellipsoid to onion-like particles, as well as the ellipsoid aspect ratio. DPD simulations produced morphologies similar to those obtained from experiments and thus elucidated the mechanism and driving forces responsible for the evaporation-induced assembly of BCPs into particles with well-defined shapes and morphologies.

  19. Sustainability issues in circuit board recycling

    DEFF Research Database (Denmark)

    Legarth, Jens Brøbech; Alting, Leo; Baldo, Gian Luca

    1995-01-01

    The resource recovery and environmental impact issues of printed circuit board recycling by secondary copper smelters are discussed. Guidelines concerning material selection for circuit board manufacture and concerning the recycling processes are given to enhance recovery efficiency and to lower...

  20. Recycled materials in Portland cement concrete

    Science.gov (United States)

    2000-06-01

    This report pertains to a comprehensive study involving the use of recycled materials in Portland cement concrete. Three different materials were studied including crushed glass (CG), street sweepings (SS), and recycled concrete (RC). Blast furnace s...

  1. Long-term aging of recycled binders.

    Science.gov (United States)

    2015-07-01

    Asphalt pavement is Americas most recycled material. Eighty million tons of asphalt, nearly 80% of all milled asphalt pavement, : is recycled every year [1]. To effectively maintain its 40,000 miles of paved roads, the Florida Department of Transp...

  2. Durable Recycled Superpave Mixes in Kansas

    Science.gov (United States)

    2018-04-01

    The use of economical and environment-friendly recycled asphalt materials has become increasingly popular for asphalt pavement construction. In general, reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) are used in hot-mix asphalt ...

  3. Transhorizon Radiowave Propagation due to Evaporation Dueting

    Indian Academy of Sciences (India)

    from the meteorological perspective, evaporation ducts have far reaching implications on radio communications ... Background Theory ... It is in this context that the tropo- .... eters that are representative of the ongoing physical processes at.

  4. Influence of Evaporation on Soap Film Rupture.

    Science.gov (United States)

    Champougny, Lorène; Miguet, Jonas; Henaff, Robin; Restagno, Frédéric; Boulogne, François; Rio, Emmanuelle

    2018-03-13

    Although soap films are prone to evaporate due to their large surface to volume ratio, the effect of evaporation on macroscopic film features has often been disregarded in the literature. In this work, we experimentally investigate the influence of environmental humidity on soap film stability. An original experiment allows to measure both the maximum length of a film pulled at constant velocity and its thinning dynamics in a controlled atmosphere for various values of the relative humidity [Formula: see text]. At first order, the environmental humidity seems to have almost no impact on most of the film thinning dynamics. However, we find that the film length at rupture increases continuously with [Formula: see text]. To rationalize our observations, we propose that film bursting occurs when the thinning due to evaporation becomes comparable to the thinning due to liquid drainage. This rupture criterion turns out to be in reasonable agreement with an estimation of the evaporation rate in our experiment.

  5. Evaporation analysis for Tank SX-104

    International Nuclear Information System (INIS)

    Barrington, C.A.

    1994-10-01

    Decreases in historical interstitial liquid level measurements in tank SX-104 were compared to predictions of a numerical model based upon diffusion of water through a porous crust. The analysis showed that observed level decreases could be explained by evaporation

  6. Denton E-beam Evaporator #2

    Data.gov (United States)

    Federal Laboratory Consortium — Description:CORAL Name: E-Beam Evap 2This is an electron gun evaporator for the deposition of metals and dielectrics thin films. Materials available are: Ag, Al, Au,...

  7. Denton E-beam Evaporator #1

    Data.gov (United States)

    Federal Laboratory Consortium — Description:CORAL Name: E-Beam Evap 1This is a dual e-beam/thermal evaporator for the deposition of metal and dielectric thin films. Materials available are: Ag, Al,...

  8. Fabrication of Josephson Junction without shadow evaporation

    Science.gov (United States)

    Wu, Xian; Ku, Hsiangsheng; Long, Junling; Pappas, David

    We developed a new method of fabricating Josephson Junction (Al/AlOX/Al) without shadow evaporation. Statistics from room temperature junction resistance and measurement of qubits are presented. Unlike the traditional ``Dolan Bridge'' technique, this method requires two individual lithographies and straight evaporations of Al. Argon RF plasma is used to remove native AlOX after the first evaporation, followed by oxidation and second Al evaporation. Junction resistance measured at room temperature shows linear dependence on Pox (oxidation pressure), √{tox} (oxidation time), and inverse proportional to junction area. We have seen 100% yield of qubits made with this method. This method is promising because it eliminates angle dependence during Junction fabrication, facilitates large scale qubits fabrication.

  9. Vapor-based interferometric measurement of local evaporation rate and interfacial temperature of evaporating droplets.

    Science.gov (United States)

    Dehaeck, Sam; Rednikov, Alexey; Colinet, Pierre

    2014-03-04

    The local evaporation rate and interfacial temperature are two quintessential characteristics for the study of evaporating droplets. Here, it is shown how one can extract these quantities by measuring the vapor concentration field around the droplet with digital holographic interferometry. As a concrete example, an evaporating freely receding pending droplet of 3M Novec HFE-7000 is analyzed at ambient conditions. The measured vapor cloud is shown to deviate significantly from a pure-diffusion regime calculation, but it compares favorably to a new boundary-layer theory accounting for a buoyancy-induced convection in the gas and the influence upon it of a thermal Marangoni flow. By integration of the measured local evaporation rate over the interface, the global evaporation rate is obtained and validated by a side-view measurement of the droplet shape. Advective effects are found to boost the global evaporation rate by a factor of 4 as compared to the diffusion-limited theory.

  10. Proceedings of the waste recycling workshop

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, R.E.; Thomas, A.F.; Ries, M.A. [eds.] [Ohio State Univ., Columbus, OH (United States)

    1993-12-31

    Recorded are seventeen talks from five sessions at the workshop. FERMCO`s recycling program, state of the art recycling technology, and an integrated demonstration of deactivation, decommissioning and decommissioning are presented in the plenary session. In the concrete session, decontamination and recycling are discussed. In the transite session, regulations are considered along with recycling and decontamination. In the metals session, radioactive scrap metals are emphasized. And in the regulatory considerations and liabilities session, DOE and EPA viewpoints are discussed. (GHH)

  11. The Diffusion Effect of MSW Recycling

    OpenAIRE

    Yi-Tui Chen; Fu-Chiang Yang; Shih-Heng Yu

    2017-01-01

    The purpose of this paper is to compare the recycling performance for some waste fractions selected including food waste, bulk waste, paper, metal products, plastics/rubber and glass products and then to develop some directions for the future improvements. The priority of each waste fraction for recycling is also analyzed by using an importance-performance analysis. Traditionally, the recycling rate that is calculated by the ratio of waste recycled to waste collected is used as an indicator t...

  12. Rate control for electron gun evaporation

    International Nuclear Information System (INIS)

    Schellingerhout, A.J.G.; Janocko, M.A.; Klapwijk, T.M.; Mooij, J.E.

    1989-01-01

    Principles for obtaining high-quality rate control for electron gun evaporation are discussed. The design criteria for rate controllers are derived from this analysis. Results are presented which have been obtained with e-guns whose evaporation rate is controlled by a Wehnelt electrode or by sweeping of the electron beam. Further improvements of rate stability can be obtained by improved design of e-guns and power supplies

  13. Towards a rational definition of potential evaporation

    OpenAIRE

    Lhomme, Jean-Paul

    1997-01-01

    International audience; The concept of potential evaporation is defined on the basis of the following criteria: (i) it must establish an upper limit to the evaporation process in a given environment (the term "environment" including meteorological and surface conditions), and (ii) this upper limit must be readily calculated from measured input data. It is shown that this upper limit is perfectly defined and is given by the Penman equation, applied with the corresponding meteorological data (i...

  14. Recycling at Penn State's Beaver Stadium. "Recycle on the Go" Success Story

    Science.gov (United States)

    US Environmental Protection Agency, 2009

    2009-01-01

    With a 13-year-old recycling program, The Pennsylvania State University's (Penn State) Beaver Stadium in the past diverted nearly 30 tons of recyclables per year from local landfills. A new initiative to promote recycling in the stadium's tailgating area has helped Penn State more than triple its old recycling record, collecting 112 tons in 2008.…

  15. Pyrolysis characteristics and pyrolysis products separation for recycling organic materials from waste liquid crystal display panels

    International Nuclear Information System (INIS)

    Wang, Ruixue; Xu, Zhenming

    2016-01-01

    Highlights: • Pyrolysis characteristics are conducted for a better understanding of LCDs pyrolysis. • Optimum design is developed which is significant to guide the further industrial process. • Acetic acid and TPP are recycled and separated. - Abstract: Waste liquid crystal display (LCD) panels mainly contain inorganic materials (glass substrate with indium-tin oxide film), and organic materials (polarizing film and liquid crystal). The organic materials should be removed beforehand since the organic matters would hinder the indium recycling process. In the present study, pyrolysis process is used to remove the organic materials and recycle acetic as well as and triphenyl phosphate (TPP) from waste LCD panels in an environmental friendly way. Several highlights of this study are summarized as follows: (i) Pyrolysis characteristics and pyrolysis kinetics analysis are conducted which is significant to get a better understanding of the pyrolysis process. (ii) Optimum design is developed by applying Box–Behnken Design (BBD) under response surface methodology (RSM) for engineering application which is significant to guide the further industrial recycling process. The oil yield could reach 70.53 wt% and the residue rate could reach 14.05 wt% when the pyrolysis temperature is 570 °C, nitrogen flow rate is 6 L min"−"1 and the particle size is 0.5 mm. (iii) Furthermore, acetic acid and TPP are recycled, and then separated by rotary evaporation, which could reduce the consumption of fossil energy for producing acetic acid, and be reused in electronics manufacturing industry.

  16. Pyrolysis characteristics and pyrolysis products separation for recycling organic materials from waste liquid crystal display panels

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruixue; Xu, Zhenming, E-mail: zmxu@sjtu.edu.cn

    2016-01-25

    Highlights: • Pyrolysis characteristics are conducted for a better understanding of LCDs pyrolysis. • Optimum design is developed which is significant to guide the further industrial process. • Acetic acid and TPP are recycled and separated. - Abstract: Waste liquid crystal display (LCD) panels mainly contain inorganic materials (glass substrate with indium-tin oxide film), and organic materials (polarizing film and liquid crystal). The organic materials should be removed beforehand since the organic matters would hinder the indium recycling process. In the present study, pyrolysis process is used to remove the organic materials and recycle acetic as well as and triphenyl phosphate (TPP) from waste LCD panels in an environmental friendly way. Several highlights of this study are summarized as follows: (i) Pyrolysis characteristics and pyrolysis kinetics analysis are conducted which is significant to get a better understanding of the pyrolysis process. (ii) Optimum design is developed by applying Box–Behnken Design (BBD) under response surface methodology (RSM) for engineering application which is significant to guide the further industrial recycling process. The oil yield could reach 70.53 wt% and the residue rate could reach 14.05 wt% when the pyrolysis temperature is 570 °C, nitrogen flow rate is 6 L min{sup −1} and the particle size is 0.5 mm. (iii) Furthermore, acetic acid and TPP are recycled, and then separated by rotary evaporation, which could reduce the consumption of fossil energy for producing acetic acid, and be reused in electronics manufacturing industry.

  17. State-of-the-art of recycling e-wastes by vacuum metallurgy separation.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2014-12-16

    In recent era, more and more electric and electronic equipment wastes (e-wastes) are generated that contain both toxic and valuable materials in them. Most studies focus on the extraction of valuable metals like Au, Ag from e-wastes. However, the recycling of metals such as Pb, Cd, Zn, and organics has not attracted enough attentions. Vacuum metallurgy separation (VMS) processes can reduce pollution significantly using vacuum technique. It can effectively recycle heavy metals and organics from e-wastes in an environmentally friendly way, which is beneficial for both preventing the heavy metal contaminations and the sustainable development of resources. VMS can be classified into several methods, such as vacuum evaporation, vacuum carbon reduction and vacuum pyrolysis. This paper respectively reviews the state-of-art of these methods applied to recycling heavy metals and organics from several kinds of e-wastes. The method principle, equipment used, separating process, optimized operating parameters and recycling mechanism of each case are illustrated in details. The perspectives on the further development of e-wastes recycling by VMS are also presented.

  18. Recycling nutrients in algae biorefinery

    NARCIS (Netherlands)

    Garcia Alba, Laura; Vos, M.P.; Torri, C.; Fabbri, D.; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

    2013-01-01

    Algal fuel cells: Repeated nutrient recycling is demonstrated by reusing the aqueous phase obtained from the hydrothermal liquefaction (HTL) of microalgae. This is achieved, for the first time, by performing a complete set of four continuous growth–HTL cycles. Results show similar growth rates in

  19. The Fulton School Recycling Project.

    Science.gov (United States)

    Lindsay, Jean

    1994-01-01

    Outlines a school recycling project that started as a newspaper collection for library funds and evolved into a community service. Discusses problems that were overcome, strategies for implementation of the project, and related cross-curricular studies and activities. Contains two curriculum mind maps. (LZ)

  20. Controlling adhesive behavior during recycling

    Science.gov (United States)

    Carl Houtman; Karen Scallon; Jihui Guo; XinPing Wang; Steve Severtson; Mark Kroll; Mike Nowak

    2004-01-01

    Adhesives can be formulated to facilitate their removal by typical paper recycling unit operations. The investigations described in this paper are focused on determining fundamental properties that control particle size during pulping. While pressure-sensitive adhesives (PSAs) with high elastic moduli tend to survive pulping with larger particles, facestock and...