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Advanced Membrane Separation Technologies for Energy Recovery from Industrial Process Streams

Description: Recovery of energy from relatively low-temperature waste streams is a goal that has not been achieved on any large scale. Heat exchangers do not operate efficiently with low-temperature streams and thus require such large heat exchanger surface areas that they are not practical. Condensing economizers offer one option for heat recovery from such streams, but they have not been widely implemented by industry. A promising alternative to these heat exchangers and economizers is a prototype ceramic membrane system using transport membrane technology for separation of water vapor and recovery of heat. This system was successfully tested by the Gas Technology Institute (GTI) on a natural gas fired boiler where the flue gas is relatively clean and free of contaminants. However, since the tubes of the prototype system were constructed of aluminum oxide, the brittle nature of the tubes limited the robustness of the system and even limited the length of tubes that could be used. In order to improve the robustness of the membrane tubes and make the system more suitable for industrial applications, this project was initiated with the objective of developing a system with materials that would permit the system to function successfully on a larger scale and in contaminated and potentially corrosive industrial environments. This required identifying likely industrial environments and the hazards associated with those environments. Based on the hazardous components in these environments, candidate metallic materials were identified that are expected to have sufficient strength, thermal conductivity and corrosion resistance to permit production of longer tubes that could function in the industrial environments identified. Tests were conducted to determine the corrosion resistance of these candidate alloys, and the feasibility of forming these materials into porous substrates was assessed. Once the most promising metallic materials were identified, the ability to form an alumina membrane layer on ...
Date: January 14, 2013
Creator: Keiser, J. R.; Wang, D.; Bischoff, B.; Ciora,; Radhakrishnan, B. & Gorti, S. B.
Partner: UNT Libraries Government Documents Department

An Experimental Study of an FEL Oscillator with a Linear Taper

Description: Motivated by the work of Saldin, Schneidmiller and Yurkov, we have measured the detuning curve widths, spectral characteristics, efficiency, and energy spread as a function of the taper for low and high Q resonators in the IR Demo FEL at Jefferson Lab. Both positive and negative tapers were used. Gain and frequency agreed reasonably well with the predictions of a single mode theory. The efficiency agreed reasonably well for a negative taper with a high Q resonator but disagreed for lower Q values due to the large slippage parameter and the non-ideal resonator Q. We saw better efficiency for a negative taper than for the same positive taper. The energy spread induced in the beam, normalized to the efficiency is larger for the positive taper than for the corresponding negative taper. This indicates that a negative taper is preferred over a positive taper in an energy recovery FEL.
Date: January 1, 2001
Creator: Benson, S.; Gubeli, J. & Neil, G.R.
Partner: UNT Libraries Government Documents Department

Is recycling the best policy option? Insights from life cycle analysis

Description: The public perceives that the more we recycle, the better off we are. However, both the concept of recycling and the benefits to be achieved from recycling are somewhat vague. To determine the best option for disposition of a material at the end of its first use, we need to first define the available options and then clarify the possible goals that can be achieved by them. The best option will depend on the material, goals to be achieved, and location-dependent factors, such as costs, resources, and regulations. This paper presents the results of a life-cycle energy analysis of kraft paper and newsprint by Argonne National Laboratory. They indicate that under some circumstances, the option of fiber-energy recovery will maximize the benefits that can. be realized from the U.S. used paper resource.
Date: March 1, 1996
Creator: Gaines, L.L. & Stodolsky, F.
Partner: UNT Libraries Government Documents Department

A Preliminary Study of Energy Recovery in Vehicles by Using Regenerative Magnetic Shock Absorbers

Description: Road vehicles can expend a significant amount of energy in undesirable vertical motions that are induced by road bumps, and much of that is dissipated in conventional shock absorbers as they dampen the vertical motions. Presented in this paper are some of the results of a study aimed at determining the effectiveness of efficiently transforming that energy into electrical power by using optimally designed regenerative electromagnetic shock absorbers. In turn, the electrical power can be used to recharge batteries or other efficient energy storage devices (e.g., flywheels) rather than be dissipated. The results of the study are encouraging - they suggest that a significant amount of the vertical motion energy can be recovered and stored.
Date: May 14, 2001
Creator: Goldner, R. B.; Zerigian, P. & Hull, J. R.
Partner: UNT Libraries Government Documents Department

Overview of the Jefferson Lab IR FEL Program

Description: Jefferson Lab (formerly known as CEBAF) is building a kilowatt-level free-electron laser operating in the mid-infrared to study technologies required for high average power operation. The design of the driver accelerator, its subsystems, and the wiggler and optical cavity will be described. We also present estimates of the output power, electron beam quality, and beam stability during energy recovery. Finally, the status of the project will be reviewed.
Date: December 1, 1996
Creator: Benson, Stephen & team, and the Jefferson Lab FEL
Partner: UNT Libraries Government Documents Department


Description: Workshop on Photo-injectors for Energy Recovery Linac was held at National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory (BNL) on January 22 and 23, 2001. Fifty people attended the workshop; they came from three countries, representing universities, industries and national laboratories. This is the first workshop ever held on photo-injectors for CW operation, and for the first time, both DC and RF photo-injectors were discussed at the workshop. Workshop covered almost all major issues of photo-injectors, photocathode, laser system, vacuum, DC, 433 MHz/B-factory cavities based RF gun, 1.3 GHz RF gun and beam instrumentation. High quantum efficiency and long live time photocathode is the issue discussed during the workshop. Four working group leaders have done great jobs summarizing the workshop discussion, and identifying the major issues for future R and D.
Date: January 22, 2001
Creator: WANG,X.J.
Partner: UNT Libraries Government Documents Department

Intense, broadband far-IR/THZ radiation from the Jlab FEL

Description: The authors calculate the spectral output from a dipole magnet in the energy recovery system of the Jefferson Laboratory Free Electron Laser (FEL) in the 1--10,000 cm{sup {minus}1} (1 micron to 1 cm) range. They show that due to multiparticle coherent enhancement (coherent synchrotron radiation or CSR), the emission contains almost 1 watt/cm{sup {minus}1} of power emitted into the diffraction limit. For the purpose of this illustrative calculation they assume some typical parameters for the machine, namely that they have 100 pico-coulomb electron bunches at a 37.4 MHz repetition rate. They also assumed full width half maximum (fwhm) horizontal and vertical beam sizes of 200 microns. They took the electron beam energy to be 40 MeV, the bending radius to be 1m, and they extracted 90 x 90 milliradians of light (approximately an {line_integral}/11 beam).
Date: February 12, 2001
Creator: Williams, Gwyn P.
Partner: UNT Libraries Government Documents Department

The Jefferson Lab 1 KW IR FEL

Description: The Jefferson Lab (JLab) IR Demo Free Electron Laser (FEL) has completed commissioning and is initiating user service. The FEL - a high repetition rate, low extraction efficiency wiggler-driven optical cavity resonator - produces over 1 kW of tuneable light on intervals in a 3-6 lim wavelength range. It is driven by a 35-48 MeV, 5 mA superconducting RF (SRF) based energy-recovering continuous wave (CW) electron linac. The driver accelerator meets requirements imposed by low energy, high current, and a demand for stringent beam control at the wiggler and during energy recovery. These constraints are driven by the need for six-dimensional phase space management, the existence of deleterious collective phenomena (space charge, wake-fields, beam break-up, and coherent synchrotron radiation), and interactions between the FEL and the accelerator RF. The authors detail the system design, relate commissioning highlights, and discuss present performance.
Date: August 1, 2000
Creator: Team, D. Douglas for the Jefferson Lab IR Demo FEL
Partner: UNT Libraries Government Documents Department

RF Stability in Energy Recovering Free Electron Lasers: Theory and Experiment

Description: Phenomena that result from the interaction of the beam with the rf fields in superconducting cavities, and can potentially limit the performance of high average power Energy Recovery Free Electron Lasers (FELs), are reviewed. These phenomena include transverse and longitudinal multipass, multibunch Beam Breakup, longitudinal beam-loading types of instabilities and their interaction with the FEL, Higher Order Mode power dissipation, emittance growth and energy spread due to short range wakefields, and rf control issues. We present experimental data obtained at the Jefferson Lab IR FEL with average current up to 5 mA, compare with analytic calculations and simulations and extrapolate the performance of Energy Recovery FELs to much higher average currents, up to approximately 100 mA. This work supported by U.S. DOE Contract No. DE-AC05-84ER40150, the Commonwealth of Virginia and the Laser Processing Consortium.
Date: August 1, 2001
Creator: Merminga, Lia
Partner: UNT Libraries Government Documents Department

Diagnostics for Recirculating and Energy Recovery Linacs

Description: In this paper, the electron beam diagnostics developed for recirculating electron accelerators will be reviewed. The main novelties in dealing with such accelerators are: to have sufficient information and control possibilities for the longitudinal phase space, to have means to accurately set the recirculation path length, and to have a means to distinguish the beam passes on measurements of position in the linac proper. The solutions to these problems obtained at Jefferson Laboratory and elsewhere will be discussed. In addition, more standard instrumentation (profiling and emittance measurements) will be reviewed in the context of recirculating linacs. Finally, and looking forward, electron beam diagnostics for applications to high current energy recovered linacs will be discussed.
Date: May 1, 2002
Creator: Krafft, Geoffrey & Denard, Jean-Claude
Partner: UNT Libraries Government Documents Department

First Lasing of the Jefferson Lab IR Demo FEL

Description: As reported previously [1], Jefferson Lab is building a free-electron laser capable of generating a continuous wave kilowatt laser beam. The driver-accelerator consists of a superconducting, energy-recovery accelerator. The initial stage of the program was to produce over 100 W of average power with no recirculation. In order to provide maximum gain the initial wavelength was chosen to be 5 mu-m and the initial beam energy was chosen to be 38.5 MeV. On June 17, 1998, the laser produced 155 Watts cw power at the laser output with a 98% reflective output coupler. On July 28th, 311 Watts cw power was obtained using a 90% reflective output coupler. A summary of the commissioning activities to date as well as some novel lasing results will be summarized in this paper. Present work is concentrated on optimizing lasing at 5 mu-m, obtaining lasing at 3 mu-m, and commissioning the recirculation transport in preparation for kilowatt lasing this fall.
Date: May 1, 1999
Creator: Benson, Stephen; Biallas, George; Bohn, Court; Douglas, David; Dylla, H.F.; Evans, R. et al.
Partner: UNT Libraries Government Documents Department


Description: An R&D facility for an Energy Recovery Linac (ERL) intended as part of an electron-cooling project for RHIC is, being constructed at this laboratory. The center piece of the facility is a 5-cell 703.75 MHz super-conducting RF linac. Successful operation will depend on effective HOM damping. It is planned to achieve HOM damping exclusively with ferrite absorbers. The performance of a prototype absorber was measured by transforming it into a resonant cavity and alternatively by a conventional wire method. The results expressed as a surface or R-square impedance are presented in this paper.
Date: July 10, 2005
Partner: UNT Libraries Government Documents Department


Description: This paper presents an overview of existing and emerging technologies on electron sources that can service various Energy Recovering Linacs under consideration. Photocathodes that can deliver average currents from 1 mA to 1 A, the pros and cons associated with these cathodes are addressed. Status of emerging technologies such as secondary emitters, cesiated dispenser cathodes, field and photon assisted field emitters and super lattice photocathodes are also reviewed.
Date: March 19, 2005
Creator: RAO, T.; BURRILL, A.; CHANG, X. Y.; SMEDLEY, J. & AL., ET
Partner: UNT Libraries Government Documents Department


Description: An energy recovery linac (ERL), under development at Brookhaven National Laboratory [1,2], will push ERLs further towards high current and high brightness beams. This R&D ERL will operate in two modes: a high current mode and a high charge mode. In this paper we present a lattice of the machine and PARMELA simulations from the cathode to the beam dump. We discuss the design considerations and present main parameters for various modes of operation.
Date: May 16, 2005
Creator: KAYRAN, D.; BEN-ZVI, I.; CALAGA, R.; CHANG, X. Y. & AL., ET
Partner: UNT Libraries Government Documents Department

Energy Recovery Linacs for Light Source Applications

Description: Energy Recovery Linacs are being considered for applications in present and future light sources. ERLs take advantage of the continuous operation of superconducting rf cavities to accelerate high average current beams with low losses. The electrons can be directed through bends, undulators, and wigglers for high brightness x ray production. They are then decelerated to low energy, recovering power so as to minimize the required rf drive and electrical draw. When this approach is coupled with advanced continuous wave injectors, very high power, ultra-short electron pulse trains of very high brightness can be achieved. This paper will review the status of worldwide programs and discuss the technology challenges to provide such beams for photon production.
Date: April 1, 2011
Creator: Neil, George
Partner: UNT Libraries Government Documents Department

LHeC ERL Design and Beam-dynamics Issues

Description: We discuss machine and beam parameter choices for a Linac-Ring option of the Large Hadron electron Collider (LHeC) based on the LHC. With the total wall-plug power limited to 100 MW and a target current of about 6 mA the desired luminosity of 1033 cm-2 s-1 can be reached, providing one exploits unique features of the Energy Recovery Linac (ERL). Here, we describe the overall layout of such ERL complex located on the LHC site. We present an optimized multi-pass linac optics enabling operation of the proposed 3-pass Recirculating Linear Accelerator (RLA) in the Energy Recovery mode. We also describe emittance preserving return arc optics architecture; including layout and optics of the arc switch-yard. Furthermore, we discuss importance of collective effects such as: beam breakup in the RLA, as well as ion accumulation, with design-integrated mitigation measures, and the electron-beam disruption in collision. Finally, a few open questions are highlighted.
Date: September 1, 2011
Creator: S.A. Bogacz, I. Shin, D. Schulte, F. Zimmermann
Partner: UNT Libraries Government Documents Department

First Considerations Concerning an Optimized Cavity Design for the Main Linac of BERLinPro

Description: The Berlin Energy Recovery Linac Project (BERLinPro) is designed to develop and demonstrate CW linac technology and expertise required to drive next-generation Energy Recovery Linacs. Strongly HOM-damped multicell 1.3 GHz cavities are required for the main linac. The optimization of the cavities presented here is primarily based on the CEBAF 1.5 GHz 5-cell high-current cavity design, including HOM waveguide couplers. The cavity was scaled to 1.3 GHz and extended to 7 cells. Modifications to the end group design have also been studied. An effort was also made to reduce the ratio Epk/Eacc while still permitting HOMs to propagate.
Date: September 1, 2011
Creator: B. Riemann, T. Weis, W. Anders, J. Knobloch, A. Neumann, H.-W. Glock, C. Potratz, U. van Rienen, F. Marhauser
Partner: UNT Libraries Government Documents Department

First Demonstration of Electron Beam Generation and Characterization with an All Superconducting Radio-frequency (SRF) Photoinjector

Description: In preparation for a high brightness, high average current electron source for the energy-recovery linac BERLinPro an all superconducting radio-frequency photoinjector is now in operation at Helmholtz-Zentrum Berlin. The aim of this experiment is beam demonstration with a high brightness electron source able to generate sub-ps pulse length electron bunches from a superconducting (SC) cathode film made of Pb coated on the backwall of a Nb SRF cavity. This paper describes the setup of the experiment and first results from beam measurements.
Date: September 1, 2011
Creator: Kamps, T; Barday, R; Jankowiak, A; Knobloch, J; Kugeler, O; Matveenko, A N et al.
Partner: UNT Libraries Government Documents Department

Studies of injection into naturally fractured reservoirs

Description: A semi-analytical model for studies of cold water injectioninto naturally fractured reservoirs has been developed. The model can beused to design the flow rates and location of injection wells in suchsystems. The results obtained using the model show that initially thecold water will move very rapidly through the fracture system away fromthe well. Later on, conductive heat transfer from the rock matrix blockswill retard the advancement of the cold water front, and eventuallyuniform energy sweep conditions will prevail. Where uniform energy sweepconditions are reached the cold waer movement away from the injectionwell will be identical to that in a porous medium; consequently maximumenergy recovery from the rock matrix will be attained. The time ofuniform energy sweep and the radial distance from the injection wellwhere it occurs are greatly dependent upon the fracture spacing, butindependent of the fracture aperture.
Date: July 1, 1982
Creator: Bodvarsson, Gudmundur S. & Lai, Cheng Hsien
Partner: UNT Libraries Government Documents Department

Closing plenary summary of working group 4 instrumentation and controls for ERL2011

Description: Working group 4 was charged with presentations and discussions on instrumentation and controls with regards to Energy Recovery Linacs (ERL). There were 4 sessions spanning 3.5 hours in which 7 talks were delivered, the first being an invited plenary presentation. The time allotted for each talk was limited to 20-25 minutes in order to allow 5-10 minutes for discussion. Most of the talks were held in joint session with working group 5 (Unwanted Beam Loss). This format was effective for the purpose of this workshop. A final series of discussion sessions were also held with working group 5. Summary of the working group 4 activities, presented in the closing plenary session. We had a plenary presentation on operational performance, experience, and future plans at the existing ERL injector prototype at Cornell. This included instrumentation data, controls system configurations, as well as description of future needs. This was followed by four talks from KEK and RIKEN/SPring-8 that described electron beam instrumentation already in use or under development that can be applied to ERL facilities. The final talks described the ERLs under construction at KEK and BNL. The format of having joint sessions with working group 5 was beneficial as there were a significant number of common topics and concerns with regards to the causes of beam loss, instrumentation hardware, and techniques used to measure and analyze beam loss.
Date: October 16, 2011
Creator: Gassner, D. & Obina, T.
Partner: UNT Libraries Government Documents Department

Higher-order mode analysis at the BNL Energy Recovery Linac

Description: Understanding the prevalence and structure of higher-order modes (HOMs) in accelerator cavities is critical because their excitation can result in problematic single bunch and multi-bunch effects. Particularly hazardous are dipole modes, which are more easily excited due to their linear field nature near the beam center. During a recent superconducting test on the energy recovery linac (ERL) cavity at Brookhaven National Laboratory (BNL), 8 of the highest-Q HOMs were measured for the first time. In conjunction with analysis of CST Microwave Studio simulation results for the ERL model, one of these modes was further studied in the copper prototype ERL cavity. A method of identifying HOMs utilizing existing holes drilled in copper cavity cells was developed and used to conclude that the observed high-Q mode was a quadrupole.
Date: August 3, 2011
Creator: Johnson, E.C.; Ben-Zvi, I.; Hahn, H.; Hammons, L. & Xu, W.
Partner: UNT Libraries Government Documents Department