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1

Management of Hanford Site non-defense production reactor spent nuclear fuel, Hanford Site, Richland, Washington  

SciTech Connect

The US Department of Energy (DOE) needs to provide radiologically, and industrially safe and cost-effective management of the non-defense production reactor spent nuclear fuel (SNF) at the Hanford Site. The proposed action would place the Hanford Site`s non-defense production reactor SNF in a radiologically- and industrially-safe, and passive storage condition pending final disposition. The proposed action would also reduce operational costs associated with storage of the non-defense production reactor SNF through consolidation of the SNF and through use of passive rather than active storage systems. Environmental, safety and health vulnerabilities associated with existing non-defense production reactor SNF storage facilities have been identified. DOE has determined that additional activities are required to consolidate non-defense production reactor SNF management activities at the Hanford Site, including cost-effective and safe interim storage, prior to final disposition, to enable deactivation of facilities where the SNF is now stored. Cost-effectiveness would be realized: through reduced operational costs associated with passive rather than active storage systems; removal of SNF from areas undergoing deactivation as part of the Hanford Site remediation effort; and eliminating the need to duplicate future transloading facilities at the 200 and 400 Areas. Radiologically- and industrially-safe storage would be enhanced through: (1) removal from aging facilities requiring substantial upgrades to continue safe storage; (2) utilization of passive rather than active storage systems for SNF; and (3) removal of SNF from some storage containers which have a limited remaining design life. No substantial increase in Hanford Site environmental impacts would be expected from the proposed action. Environmental impacts from postulated accident scenarios also were evaluated, and indicated that the risks associated with the proposed action would be small.

NONE

1997-03-01

2

Experimental studies of radially heterogeneous liquid metal fast breeder reactor critical assemblies at the zero-power plutonium reactor  

Microsoft Academic Search

Experimental programs to investigate the physics characteristics of heterogeneous liquid metal fast breeder reactor cores have been conducted in the zero-power plutonium reactor critical facility over a period of about5 yr. Previous experiments on conventional homogeneous cores provided appropriate benchmark data against which to judge the heterogeneous core results. For a heterogeneous reactor of the Clinch River Breeder Reactor size,

H. F. McFarlane; S. B. Brumbach; S. G. Carpenter; P. J. Collins; D. N. Olsen

1984-01-01

3

Decommissioning of eight surplus production reactors at the Hanford Site, Richland, Washington. Addendum (Final Environmental Impact Statement)  

SciTech Connect

The first section of this volume summarizes the content of the draft environmental impact statement (DEIS) and this Addendum, which together constitute the final environmental impact statement (FEIS) prepared on the decommissioning of eight surplus plutonium production reactors at Hanford. The FEIS consists of two volumes. The first volume is the DEIS as written. The second volume (this Addendum) consists of a summary; Chapter 9, which contains comments on the DEIS and provides DOE`s responses to the comments; Appendix F, which provides additional health effects information; Appendix K, which contains costs of decommissioning in 1990 dollars; Appendix L, which contains additional graphite leaching data; Appendix M, which contains a discussion of accident scenarios; Appendix N, which contains errata; and Appendix 0, which contains reproductions of the letters, transcripts, and exhibits that constitute the record for the public comment period.

Not Available

1992-12-01

4

Isotope Production at the Hanford Site in Richland, Washington  

SciTech Connect

This report was prepared in response to a request from the Nuclear Energy Research Advisory Committee (NERAC) subcommittee on ''Long-Term Isotope Research and Production Plans.'' The NERAC subcommittee has asked for a reply to a number of questions regarding (1) ''How well does the Department of Energy (DOE) infrastructure sme the need for commercial and medical isotopes?'' and (2) ''What should be the long-term role of the federal government in providing commercial and medical isotopes?' Our report addresses the questions raised by the NERAC subcommittee, and especially the 10 issues that were raised under the first of the above questions (see Appendix). These issues are related to the isotope products offered by the DOE Isotope Production Sites, the capabilities and condition of the facilities used to produce these products, the management of the isotope production programs at DOE laboratories, and the customer service record of the DOE Isotope Production sites. An important component of our report is a description of the Fast Flux Test Facility (FFTF) reactor at the Hbford Site and the future plans for its utilization as a source of radioisotopes needed by nuclear medicine physicians, by researchers, and by customers in the commercial sector. In response to the second question raised by the NERAC subcommittee, it is our firm belief that the supply of isotopes provided by DOE for medical, industrial, and research applications must be strengthened in the near future. Many of the radioisotopes currently used for medical diagnosis and therapy of cancer and other diseases are imported from Canada, Europe, and Asia. This situation places the control of isotope availability, quality, and pricing in the hands of non-U.S. suppliers. It is our opinion that the needs of the U.S. customers for isotopes and isotope products are not being adequately served, and that the DOE infrastructure and facilities devoted to the supply of these products must be improved This perception forms one of the fundamental bases for our proposal that the FFTF, which is currently in a standby condition, be reactivated to supply nuclear services and products such as radioisotopes needed by the U.S. medical, industrial, and research communities.

Ammoniums

1999-06-01

5

75 FR 43158 - Amended Record of Decision for the Decommissioning of Eight Surplus Production Reactors at the...  

Federal Register 2010, 2011, 2012, 2013

...Decision for the Decommissioning of Eight Surplus Production Reactors at the Hanford Site...Statement on Decommissioning of Eight Surplus Production Reactors at the Hanford Site, Richland, WA (Surplus Production Reactors Final EIS)...

2010-07-23

6

Transfer of Plutonium-Uranium Extraction Plant and N Reactor irradiated fuel for storage at the 105-KE and 105-KW fuel storage basins, Hanford Site, Richland Washington.  

National Technical Information Service (NTIS)

The U.S. Department of Energy (DOE) needs to remove irradiated fuel from the Plutonium-Uranium Extraction (PUREX) Plant and N Reactor at the Hanford Site, Richland, Washington, to stabilize the facilities in preparation for decontamination and decommissio...

1995-01-01

7

Environmental Assessment: Relocation and storage of TRIGA{reg_sign} reactor fuel, Hanford Site, Richland, Washington  

SciTech Connect

In order to allow the shutdown of the Hanford 308 Building in the 300 Area, it is proposed to relocate fuel assemblies (101 irradiated, three unirradiated) from the Mark I TRIGA Reactor storage pool. The irradiated fuel assemblies would be stored in casks in the Interim Storage Area in the Hanford 400 Area; the three unirradiated ones would be transferred to another TRIGA reactor. The relocation is not expected to change the offsite exposure from all Hanford Site 300 and 400 Area operations.

NONE

1995-08-01

8

Masters Thesis- Criticality Alarm System Design Guide with Accompanying Alarm System Development for the Radioisotope Production Laboratory in Richland, Washington  

SciTech Connect

A detailed instructional manual was created to guide criticality safety engineers through the process of designing a criticality alarm system (CAS) for Department of Energy (DOE) hazard class 1 and 2 facilities. Regulatory and technical requirements were both addressed. A list of design tasks and technical subtasks are thoroughly analyzed to provide concise direction for how to complete the analysis. An example of the application of the design methodology, the Criticality Alarm System developed for the Radioisotope Production Laboratory (RPL) of Richland, Washington is also included. The analysis for RPL utilizes the Monte Carlo code MCNP5 for establishing detector coverage in the facility. Significant improvements to the existing CAS were made that increase the reliability, transparency, and coverage of the system.

Greenfield, Bryce A.

2009-12-20

9

11. Building Layout, 185189 D, U.S. Atomic Energy Commission, Richland ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Building Layout, 185-189 D, U.S. Atomic Energy Commission, Richland Operations Office, Dwg. No. H-1-14844, 1957. - D-Reactor Complex, Deaeration Plant-Refrigeration Buildings, Area 100-D, Richland, Benton County, WA

10

Plutonium and tritium produced in the Hanford Site production reactors  

SciTech Connect

In a news release on December 7, 1993, the Secretary of Energy announced declassification action that included totals for plutonium and tritium production in the Hanford Site production reactors. This information was reported as being preliminary because it was not fully supported by documentation. Subsequently, production data were made available from the US Department of Energy-Headquarters (DOE-HQ) records that indicated an increase of about one and one-half metric tons in total plutonium production. The Westinghouse Hanford Company was tasked by the US Department of Energy-Richland Operations Office to substantiate production figures and DOE-HQ data and to provide a defensible report of weapons- (6 wt% {sup 240}Pu) and nonweapons- (fuels-)grade (nominally 9 wt% or higher {sup 240}Pu) plutonium and tritium production in the Hanford Site production reactors. The task was divided into three parts. The first part was to determine plutonium and tritium production based on available reported accountability records. The second part was to determine plutonium production independently by calculational checks based on reactor thermal power generation and plutonium conversion factors representing the various reactor fuels. The third part was to resolve differences, if they occurred, in the reported and calculational results. In summary, the DOE-HQ-reported accountability records of plutonium and tritium production were determined to be the most defensible record of Hanford Site reactor production. The DOE-HQ records were consistently supported by the independent calculational checks and the records of operational data. Total production quantities are 67.4 MT total plutonium, which includes 12.9 MT of nonweapons-grade plutonium. The total tritium production was 10.6 kg.

Roblyer, S.P.

1994-09-28

11

Gas Production in Reactor Materials  

SciTech Connect

This paper presents an overview of the principal nuclear reactions that are known to produce hydrogen and helium in irradiated materials and a summary of the comparison of measurements with predictions in various reactors. Hydrogen and helium are produced in all reactor materials by fast neutron reactions which typically have thresholds above 4 MeV. Selected elements also have thermal neutron gas production reactions that can be quite prolific, such as 6Li, 10B, and 14N, and there are a number of elements which produce transmutation products that have high thermal neutron gas production cross sections, most notably 59Ni produced by irradiation of Ni and 65Zn produced by irradiation of Cu or Zn. Since gas production cross sections are isotope-specific, gas production rates can change during irradiation due to transmutation effects or initial rates can be modified by isotopic tailoring of reactor materials.

Greenwood, Lawrence R.

2006-01-18

12

Hydrogen production in solar reactors  

Microsoft Academic Search

The present work summarizes the recent activities of our laboratory in the field of solar-aided hydrogen production with structured monolithic solar reactors. This reactor concept, “transferred” from the well-known automobile exhaust catalytic after-treatment systems, employs ceramic supports optimized to absorb effectively solar radiation and develop sufficiently high temperatures, that are coated with active materials capable to perform\\/catalyze a variety of

Christos C. Agrafiotis; Chrysoula Pagkoura; Souzana Lorentzou; Margaritis Kostoglou; Athanasios G. Konstandopoulos

2007-01-01

13

Status report of confinement studies Douglas United Nuclear operated reactors.  

National Technical Information Service (NTIS)

Confinement studies on the Hanford Production reactors were started in March at the request of the Richland Operations Office. The confinement studies were then undertaken with the following objectives established: (1) review and reestablish if necessary,...

J. R. Spink N. F. Fifer

1965-01-01

14

Characterization of stored defense production spent nulcear fuel and associated materials at Hanford Site, Richland Washington: Environmental assessment  

SciTech Connect

There are about 2,100 tonnes (2,300 tons) of defense production spent nuclear fuel stored in the 100-K Area Basins located along the south shore of the Columbia River in the northern part of the Hanford Site. Some of the fuel which has been in storage for a number of years is in poor condition and continues to deteriorate. The basins also contain fuel fragments and radioactively contaminated sludge. The DOE needs to characterize defense production spent nuclear fuel and associated materials stored on the Hanford Site. In order to satisfy that need, the Department of Energy (DOE) proposes to select, collect and transport samples of spent nuclear fuel and associated materials to the 327 Building for characterization. As a result of that characterization, modes of interim storage can be determined that would be compatible with the material in its present state and alternative treatment processes could be developed to permit a broader selection of storage modes. Environmental impacts of the proposed action were determined to be limited principally to radiation exposure of workers, which, however, were found to be small. No health effects among workers or the general public would be expected under routine operations. Implementation of the proposed action would not result in any impacts on cultural resources, threatened, endangered and candidate species, air or water quality, socioeconomic conditions, or waste management.

NONE

1995-03-01

15

Increase productivity with novel reactor design  

SciTech Connect

Hydrocarbon processing industry (HPI) operators have always desired flexible control over process temperature as the chemical reactions proceeded. By managing reaction temperature, petrochemical manufacturers can optimize other processing variables, thus increasing product yields and minimizing wastes and byproducts. Diverse requirements of the HPI have spawned many different reactor types. Each design has benefits but also limitations. Ongoing challenges in reactor development include large pressure drop, high catalyst inventory, labor-intensive change-out of catalysts, etc. Two case histories explore using adiabatic and nonadiabatic reactor technology for exothermic and endothermic reactions.

Arakawa, S.T.; Mulvaney, R.C.; Felch, D.E.; Petri, J.A.; Vandenbussche, K.; Dandekar, H.W. [UOP LLC, Des Plaines, IL (United States)

1998-03-01

16

Production of molybdenum-99 using solution reactors  

SciTech Connect

This paper presents the results of a study investigating the feasibility of the use of solution (or homogenous) reactors to produce {sup 99}Mo for medical applications. The goal of this experiment was to irradiate small quantities of uranyl nitrate in a solution reactor to produce {sup 99}Mo and to subsequently extract that {sup 99}Mo from the fuel solution using an on-line single-phase extraction process. Further, the experiment investigated the process efficiency and product purity. The experiments were performed using the SHEBA reactor at Los Alamos National Laboratory.

Glenn, D.E. [Department of Energy, Los Alamos, NM (United States); Heger, S. [Univ. of New Mexico, Albuquerque, NM (United States); Ball, R.

1996-12-31

17

Continuous ethanol production by immobilized yeast reactor  

Microsoft Academic Search

Saccharomyces cerevisiae yeast immobilized in calcium alginate gel beads was employed in packed-bed column reactors for continuous ethanol production from glucose or cane molasses, and for beer fermentation from barley malt wort. With properly balanced nutrient content or periodical regeneration of cells by nutrient addition and aeration, ethanol production could be maintained for several months. About 7 percent (w\\/v) ethanol

Yu-Yen Linko; P. Linko

1981-01-01

18

Hydrogen production using modular hellum reactor  

Microsoft Academic Search

The high-temperature characteristics of the Modular Helium Reactor (MHR) make it a strong candidate for the production of hydrogen using either thermochemical or high- temperature electrolysis (HTE) processes. Using heat from the MHR to drive a Sulfur-Iodine (SI) thermochemical hydrogen process has been the subject of a DOE sponsored Nuclear Engineering Research Initiative (NERI) project lead by General Atomics, with

A Shenoy; SM Mohsin Reza; Matt Richards; General Atomics

1996-01-01

19

Biodiesel production using a membrane reactor  

Microsoft Academic Search

The immiscibility of canola oil in methanol provides a mass-transfer challenge in the early stages of the transesterification of canola oil in the production of fatty acid methyl esters (FAME or biodiesel). To overcome or rather, exploit this situation, a two-phase membrane reactor was developed to produce FAME from canola oil and methanol. The transesterification of canola oil was performed

M. A. Dubé; A. Y. Tremblay; J. Liu

2007-01-01

20

Membrane reactor application to hydrogen production  

Microsoft Academic Search

Selective removal of hydrogen in a membrane reactor enables the hydrogen production by steam reforming at lower reaction temperatures than conventional processes. We invented a composite membrane consisting of thin palladium layer deposited on the outer surface of porous ceramics by electroless-plating. The palladium layer could completely cover the surface, so that only hydrogen could permeate through the membrane with

E Kikuchi

2000-01-01

21

Drart environmental impact statement siting, construction, and operation of New Production Reactor capacity. Volume 4, Appendices D-R  

SciTech Connect

This Environmental Impact Statement (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site near Aiken, South Carolina. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public. This volume contains 15 appendices.

Not Available

1991-04-01

22

Draft environmental impact statement for the siting, construction, and operation of New Production Reactor capacity. Volume 1, Summary  

SciTech Connect

This Environmental Impact Statement (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site near Aiken, South Carolina. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public.

Not Available

1991-04-01

23

Hydrogen Production Using the Modular Helium Reactor  

SciTech Connect

The high-temperature characteristics of the Modular Helium Reactor (MHR) make it a strong candidate for the production of hydrogen using either thermochemical or high-temperature electrolysis (HTE) processes. Using heat from the MHR to drive a Sulfur-Iodine (S-I) thermochemical hydrogen process has been the subject of a DOE sponsored Nuclear Engineering Research Initiative (NERI) project lead by General Atomics, with participation from the Idaho National Engineering and Environmental Laboratory (INEEL) and Texas A&M University. While the focus of much of the initial work was on the S-I thermochemical production of hydrogen, recent activities have also included development of a preconceptual design for an integral HTE hydrogen production plant driven by the process heat and electricity produced by a 600 MWt MHR. This paper describes RELAP5-3D analyses performed to evaluate alternative primary system cooling configurations for the MHR to minimize peak reactor vessel and core temperatures while achieving core helium outlet temperatures in the range of 900 oC to 1000 oC, needed for the efficient production of hydrogen using either the S-I thermochemical or HTE process. The cooling schemes investigated are intended to ensure peak fuel temperatures do not exceed specified limits under normal or transient upset conditions, and that reactor vessel temperatures do not exceed ASME code limits for steady-state or transient conditions using standard LWR vessel materials. Preconceptual designs for both an S-I thermochemical and HTE hydrogen production plant driven by a 600 MWt MHR at helium outlet temperatures in the range of 900 oC to 1000 oC are described and compared. An initial SAPHIRE model to evaluate the reliability, maintainablility, and availability of the S-I hydrogen production plant is also discussed, and plans for future assessments of conceptual designs for both a S-I thermochemical and HTE hydrogen production plant coupled to a 600 MWt modular helium reactor are described.

E. A. Harvego; S. M. Reza; M. Richards; A. Shenoy

2005-05-01

24

Green nanoparticle production using micro reactor technology  

NASA Astrophysics Data System (ADS)

The importance and potential of nanoparticles in daily life as well as in various industrial processes is becoming more predominant. Specifically, silver nanoparticles are increasingly applied, e.g. in clothes and wipes, due to their antibacterial properties. For applications in liquid phase it is advantageous to produce the nanoparticles directly in suspension. This article describes a green production of silver nanoparticles using micro reactor technology considering principles of green chemistry. The aim is to reveal the potential and constraints of this approach and to show, how economic and environmental costs vary depending on process conditions. For this purpose our research compares the proposed process with water-based batch synthesis and demonstrates improvements in terms of product quality. Because of the lower energy consumption and lower demand of cleaning agents, micro reactor is the best ecological choice.

Kück, A.; Steinfeldt, M.; Prenzel, K.; Swiderek, P.; Gleich, A. v.; Thöming, J.

2011-07-01

25

Innovative energy production in fusion reactors  

Microsoft Academic Search

Concepts of innovative energy production in neutron-lean fusion reactors without having the conventional turbine-type generator are proposed for improving the plant efficiency. These concepts are: (1) traveling wave direct energy conversion of 14.7 MeV protons; (2) cusp type direct energy conversion of charged particles; (3) efficient use of radiation with semiconductor and supplying clean fuel in a form of hydrogen

A. Iiyoshi; H. Momota; O. Motojima; M. Okamoto; S. Sudo; Y. Tomita; S. Yamaguchi; M. Ohnishi; M. Onozuka; C. Uenosono

1993-01-01

26

The behavior of fission products during nuclear rocket reactor tests  

NASA Astrophysics Data System (ADS)

Fission product release from nuclear rocket propulsion reactor fuel is an important consideration for nuclear rocket development and application. Fission product data from the last six reactors of the Rover program are collected in this paper to provide as basis for addressing development and testing issues. Fission product loss from the fuel will depend on fuel composition and reactor design and operating parameters. During ground testing, fission products can be contained downstream of the reactor. The last Rover reactor tested, the Nuclear Furnance, was mated to an effluent clean-up system that was effective in preventing the discharge of fission products into the atmosphere.

Bokor, Peter C.; Kirk, William L.; Bohl, Richard J.

1991-01-01

27

Feasibility study of a magnetic fusion production reactor  

Microsoft Academic Search

A magnetic fusion reactor can produce 10.8 kg of tritium at a fusion power of only 400 MW —an order of magnitude lower power than that of a fission production reactor. Alternatively, the same fusion reactor can produce 995 kg of plutonium. Either a tokamak or a tandem mirror production plant can be used for this purpose; the cost is

R. W. Moir

1986-01-01

28

Radiolytic production of chemical fuels in fusion reactor systems  

Microsoft Academic Search

Miley's energy flow diagram for fusion reactor systems is extended to include radiolytic production of chemical fuel. Systematic study of the economics and the overall efficiencies of fusion reactor systems leads to a criterion for evaluating the potential of radiolytic production of chemical fuel as a means of enhancing the performance of a fusion reactor system. The ecumenicity of the

Fish

1977-01-01

29

(Fission product transport processes in reactor accidents)  

SciTech Connect

The purpose of this trip was to participate in and to hold informal discussions with other participants in the International Centre for Heat and Mass Transfer (ICHMT) International Seminar on Fission Product Transport Processes held at Dubrovnik, Yugoslavia, during the week of May 22--26, 1989. There were 129 participants from 20 countries at the Seminar. The travelers delivered two invited lectures and presented four invited papers based upon NRC-sponsored work at Oak Ridge National Laboratory. One of the travelers also served as Chairman of the Session entitled Transport Phenomena in the Reactor Coolant System'' and appeared as a Panelist in the Closing Session of the Seminar.

Hodge, S.A.; Beahm, E.C.; Kress, T.S.; Malinauskas, A.P.

1989-06-14

30

High-productivity continuous biofilm reactor for butanol production  

Microsoft Academic Search

Corn steep liquor (CSL), a byproduct of the corn wet-milling process, was used in an immobilized cell continuous biofilm reactor\\u000a to replace the expensive P2 medium ingredients. The use of CSL resulted in the production of 6.29 g\\/L of total acetone-butanol-ethanol\\u000a (ABE) as compared with 6.86 g\\/L in a control experiment. These studies were performed at a dilution rate of

Nasib Qureshi; Patrick Karcher; Michael Cotta; Hans P. Blaschek

2004-01-01

31

Aerosol research at Hanford and engineering applications to production reactors  

Microsoft Academic Search

When the construction of the confinement facilities for Hanford production reactors is completed, the potential for contaminating the environment with accidentally released fission products will be greatly reduced. This was demonstrated already when rupture debris burned in the rear face area of one of the reactors in which the fog spray was installed and ready for service. The fog spray

C. E. Linderoth; H. W. Heacock; L. C. Schwendiman

2009-01-01

32

Modeling issues associated with production reactor safety assessment  

Microsoft Academic Search

This paper describes several Probabilistic Safety Assessment (PSA) modeling issues that are related to the unique design and operation of the production reactors. The identification of initiating events and determination of a set of success criteria for the production reactors is of concern because of their unique design. The modeling of accident recovery must take into account the unique operation

D. W. Stack; W. R. Thomas

1990-01-01

33

POTENTIAL BENCHMARKS FOR ACTINIDE PRODUCTION IN HANFORD REACTORS  

SciTech Connect

A significant experimental program was conducted in the early Hanford reactors to understand the reactor production of actinides. These experiments were conducted with sufficient rigor, in some cases, to provide useful information that can be utilized today in development of benchmark experiments that may be used for the validation of present computer codes for the production of these actinides in low enriched uranium fuel.

PUIGH RJ; TOFFER H

2011-10-19

34

Draft environmental impact statement for the siting, construction, and operation of New Production Reactor capacity. Volume 3, Sections 7-12, Appendices A-C  

SciTech Connect

This Environmental Impact Statement (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site near Aiken, South Carolina. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public. This volume contains references; a list of preparers and recipients; acronyms, abbreviations, and units of measure; a glossary; an index and three appendices.

Not Available

1991-04-01

35

Draft environmental impact statement for the siting, construction, and operation of New Production Reactor capacity. Volume 2, Sections 1-6  

SciTech Connect

This (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public. This volume contains the analysis of programmatic alternatives, project alternatives, affected environment of alternative sites, environmental consequences, and environmental regulations and permit requirements.

Not Available

1991-04-01

36

The behavior of fission products during nuclear rocket reactor tests  

NASA Astrophysics Data System (ADS)

The experience base regarding fission product behavior developed during the Rover program, the nuclear rocket development program of 1955 to 1972 will be useful in planning a renewed nuclear rocket program. During the Rover program, 20 reactors were tested at the Nuclear Rocket Development Station in Nevada. Nineteen of these discharged effluent directly into the atmosphere; the last reactor tested, a non-flight-prototypic, fuel-element-testing reactor called the Nuclear Furnace (NF-1) was connected to an effluent cleanup system that removed fission products before the hydrogen coolant (propellant) was discharged to the atmosphere. In general, we are able to increase both test duration and fuel temperature during the test series. Therefore fission product data from the later part of the program are more interesting and more applicable to future reactors. We have collected fission product retention (and release) data reported in both formal and informal publications for six of the later reactor tests; five of these were Los Alamos reactors that were firsts of a kind in configuration or operating conditions. We have also, with the cooperation of Westinghouse, included fission product data from the NRX-A6 reactor, the final member of a series of developmental reactors with the same basic geometry, but with significant design and fabrication improvements as the series continued. Table 1 lists the six selected reactors and the test parameters for each.

Bokor, Peter C.; Kirk, William L.; Bohl, Richard J.

37

The behavior of fission products during nuclear rocket reactor tests  

SciTech Connect

The experience base regarding fission product behavior developed during the Rover program, the nuclear rocket development program of 1955--1972, will be useful in planning a renewed nuclear rocket program. During the Rover program, 20 reactors were tested at the Nuclear Rocket Development Station in Nevada. Nineteen of these discharged effluent directly into the atmosphere; the last reactor tested, a non-flight-prototypic, fuel-element-testing reactor called the Nuclear Furnace (NF-1) was connected to an effluent cleanup system that removed fission products before the hydrogen coolant (propellant) was discharged to the atmosphere. In general, we are able to increase both test duration and fuel temperature during the test series. Therefore fission product data from the later part of the program are more interesting and more applicable to future reactors. We have collected fission product retention (and release) data reported in both formal and informal publications for six of the later reactor tests; five of these were Los Alamos reactors that were firsts of a kind in configuration or operating conditions. We have also, with the cooperation of Westinghouse, included fission product data from the NRX-A6 reactor, the final member of series of developmental reactors with the same basic geometry, but with significant design and fabrication improvements as the series continued. Table 1 lists the six selected reactors and the test parameters for each.

Bokor, P.C.; Kirk, W.L.; Bohl, R.J.

1991-01-01

38

Supplying the nuclear arsenal: American production reactors, 1942--1992  

SciTech Connect

Although the history of commercial-power nuclear reactors is well known, the story of the government reactors that produce weapons-grade plutonium and tritium has been shrouded in secrecy. In the first detailed look at the origin and development of these production reactors, the authors describe a fifty-year government effort no less complex, expensive, and technologically demanding than the Polaris or Apollo programs--yet one about which most Americans know virtually nothing. The book describes the evolution of the early reactors, the atomic weapons establishment that surrounded them, and the sometimes bitter struggles between business and political constituencies for their share of 'nuclear pork.' They show how, since the 1980s, aging production reactors have increased the risk of radioactive contamination of the atmosphere and water table. And they describe how the Department of Energy mounted a massive effort to find the right design for a new generation of reactors, only to abandon that effort with the end of the Cold War. Today, all American production reactors remain closed. Due to short half-life, the nation's supply of tritium, crucial to modern weapons, is rapidly dwindling. As countries like Iraq and North Korea threaten to join the nuclear club, the authors contend, the United States needs to revitalize tritium production capacity in order to maintain a viable nuclear deterrent. Meanwhile, as slowly decaying artifacts of the Cold War, the closed production reactors at Hanford, Washington, and Savannah River, South Carolina, loom ominously over the landscape.

Carlisle, R.P.; Zenzen, J.M.

1996-01-01

39

Corrosion-product release in light water reactors  

SciTech Connect

This research project is aimed at studying corrosion-product release from a range of reactor alloys under both PWR and BWR coolant chemistry conditions. The results of such a study will be ued to recommend ways by which corrosion-product release, and subsequent radiation fields, can be minimized in reactors. The investigation of corrosion-product release has so far employed three main techniques: in-reactor loop experiments to provide data on the effects of coolant chemistry and reactor irradiation; out-reactor loop experiments to provide kinetics data on release; and a combined radiotracer-surface analytical study of oxide films to provide mechanistic information on release. The results of the first year of the program are presented and discussed.

Lister, D.H.

1984-03-01

40

Fission product scrubbing system for a nuclear reactor  

Microsoft Academic Search

A fission product scrubbing system is described for a nuclear reactor including a containment building defining a containment space for accommodating reactor components, comprising (a) means defining a water tank in the containment building; (b) a dividing wall extending into the water tank for separating the water tank into a first and a second compartment; (c) means defining a collection

1986-01-01

41

Survey of dust production in pebble bed reactor cores  

Microsoft Academic Search

Graphite dust produced via mechanical wear from the pebbles in a pebble bed reactor is an area of concern for licensing. Both the German pebble bed reactors produced graphite dust that contained activated elements. These activation products constitute an additional source term of radiation and must be taken under consideration during the conduct of accident analysis of the design. This

Joshua J. Cogliati; Abderrafi M. Ougouag; Javier Ortensi

2011-01-01

42

A shell-and-tube pyrolysis reactor for olefin production  

SciTech Connect

In this paper, a new thermal cracking technology using shell-and-tube type pyrolysis reactors, in which the accent is shifted from radiative to convective heat transfer, is introduced. A smooth temperature distribution can be achieved with the proposed reactor geometry. This lowers the coking rate and increases the run length of the reactor and the lifetime of the tubes. A reactor model accounting in great detail for the reactor geometry and the different heat-transfer mechanisms is combined with a rigorous kinetic model based on radical reaction mechanisms to predict the temperature distribution in the reactor, the heat transfer from flue gas to process gas, and the naphtha conversion, together with the associated product yields for the various tubes.

Heyndericks, G.J.; Froment, G.B. (Laboratorium voor Petrochemische Techniek, Rijksuniversiteit, Krijgslaan 281, B9000 Gent (Belgium)); Martin, G.H. (Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France))

1992-09-01

43

Homogeneous fast-flux isotope-production reactor  

DOEpatents

A method is described for producing tritium in a liquid metal fast breeder reactor. Lithium target material is dissolved in the liquid metal coolant in order to facilitate the production and removal of tritium.

Cawley, W.E.; Omberg, R.P.

1982-08-19

44

Survey of Dust Production in Pebble Bed Reactors Cores  

SciTech Connect

Graphite dust produced via mechanical wear from the pebbles in a pebble bed reactor is an area of concern for licensing. Both the German pebble bed reactors produced graphite dust that contained activated elements. These activation products constitute an additional source term of radiation and must be taken under consideration during the conduct of accident analysis of the design. This paper discusses the available literature on graphite dust production and measurements in pebble bed reactors. Limited data is available on the graphite dust produced from the AVR and THTR-300 pebble bed reactors. Experiments that have been performed on wear of graphite in pebble-bed-like conditions are reviewed. The calculation of contact forces, which are a key driving mechanism for dust in the reactor, are also included. In addition, prior graphite dust predictions are examined, and future areas of research are identified.

Joshua J. Cogliati; Abderafi M. Ougouag; Javier Ortensi

2011-06-01

45

Richland Environmental Restoration Project management action process document  

SciTech Connect

A critical mission of the U.S. Department of Energy (DOE) is the planning, implementation, and completion of environmental restoration programs at DOE facilities. An integral part of this mission involves the safe and cost-effective environmental restoration of the Hanford Site. For over 40 years the Hanford Site supported United States national defense programs, largely through the production of nuclear materials. One legacy of historical Hanford Site operations is a significant waste inventory of radioactive and/or regulated chemical materials. Releases of these materials have, in some cases, contaminated the Hanford Site environment. The DOE Richland Operations Office (RL) is responsible for protecting human health and the environment from potential Hanford Site environmental hazards by identifying, assessing, and mitigating risks posed by contaminated sites.

NONE

1996-04-01

46

Polymer product engineering utilising oscillatory baffled reactors  

Microsoft Academic Search

The Oscillatory baffled reactor (OBR) can be used to produce particles with controlled size and morphology, in batch or continuous flow. This is due to the effect of the superimposed oscillations that radially mixes fluid but still allows plug-flow (or close to plug flow) behaviour in a continuous system. This mixing, combined with a close to a constant level of

Xiongwei Ni; K. R Murray; Yanmin Zhang; Daniel Bennett; Tony Howes

2002-01-01

47

Economics of power plant district and process heating in Richland, Washington  

SciTech Connect

The economic feasibility of utilizing hot water from nuclear reactors to provide district heating for private residences in Richland, Washington, and space and process heating for nearby offices, part of the Hanford Reservation, and the Lamb-Weston potato processing plant is assessed. Specifically, the practicality of using hot water from the Washington Public Power Supply System's WNP-1 reactor, which is currently under construction on the Hanford Reservation, just north of the City of Richland is established. World-wide experience with district heating systems and the advantages of using these systems are described. The GEOCITY computer model used to calculate district heating costs is described and the assumptions upon which the costs are based are presented. District heating costs for the city of Richland, process heating costs for the Lamb-Weston potato processing plant, district heating costs for the Horn Rapids triangle area, and process heating costs for the 300 and 3000 areas are discussed. An economic analysis is discussed and institutional restraints are summarized. (MCW)

Fassbender, L.L.; Bloomster, C.H.

1981-04-01

48

Chemistry of fission product iodine under nuclear reactor accident conditions  

SciTech Connect

The radioisotopes of iodine are generally acknowledged to be the species whose release into the biosphere as a result of a nuclear reactor accident is of the greatest concern. In the course of its release, the fission product is subjected to differing chemical environments; these can alter the physicochemical form of the fission product and thus modify the manner and extent to which release occurs. Both the chemical environments which are characteristic of reactor accidents and their effect in determining physical and chemical form of fission product iodine have been studied extensively, and are reviewed in this report. 76 refs.

Malinauskas, A.P.; Bell, J.T.

1986-01-01

49

Two photons correlated production at the 25MWTh reactor  

SciTech Connect

We have performed an extensive search for correlated production of two or more photons at the 25MWTh reactor at Swierk/Poland/. We were looking for a prompt signal originating from decays of axions. Our experimental set-up consisted of an arry of nine 3'' x 3'' NaI/Tl/detectors, surrounded by active/plastic scintillators/ and passive shieldings, thus ncreasing experimental sensitivity as compared to other experiments in which two detectors were used. Data were collected during 26 weeks, with four days of reactor ''ON'', and three days of reactor ''OFF'' each week. Preliminary results are presented.

Abramowicz, H.; Doroba, K.; Walczak, R.; Gorski, M.; Jasin-acute-accentski, A.; Kozl-dash-barowski, T.; Ratyn-acute-accentski, W.; Szeptycka, M.; Szymczak, M.; Tucholski, A.; and others

1985-01-15

50

Two photons correlated production at the 25MWTh reactor  

NASA Astrophysics Data System (ADS)

We have performed an extensive search for correlated production of two or more photons at the 25MWTh reactor at Swierk/Poland/. We were looking for a prompt signal originating from decays of axions. Our experimental set-up consisted of an arry of nine 3`×3` NaI/Tl/detectors, surrounded by active/plastic scintillators/ and passive shieldings, thus ncreasing experimental sensitivity as compared to other experiments in which two detectors were used. Data were collected during 26 weeks, with four days of reactor ``ON'', and three days of reactor ``OFF'' each week. Preliminary results are presented.

Abramowicz, H.; Doroba, K.; Walczak, R.; Górski, M.; Jasi?ski, A.; Koz?Owski, T.; Raty?ski, W.; Szeptycka, M.; Szymczak, M.; Tucholski, A.

1985-01-01

51

Wetlands: Their impact on siting a proposed nuclear production reactor  

Microsoft Academic Search

The Savannah River Site (SRS) is a 780-km[sup 2] US Department of Energy (DOE) site managed by the Westinghouse Savannah River Company for the production of nuclear materials for defense and other purposes. Five nuclear production reactors (NPRs) constructed in the 1950s are located on the site, and all but one are either on standby or shut down. The possibility

K. L. Hooker; S. A. Danker; A. R. Grainger; V. A. Rogers

1993-01-01

52

Feasibility study of a magnetic fusion production reactor  

NASA Astrophysics Data System (ADS)

A magnetic fusion reactor can produce 10.8 kg of tritium at a fusion power of only 400 MW —an order of magnitude lower power than that of a fission production reactor. Alternatively, the same fusion reactor can produce 995 kg of plutonium. Either a tokamak or a tandem mirror production plant can be used for this purpose; the cost is estimated at about 1.4 billion (1982 dollars) in either case. (The direct costs are estimated at 1.1 billion.) The production cost is calculated to be 22,000/g for tritium and 260/g for plutonium of quite high purity (1%240Pu). Because of the lack of demonstrated technology, such a plant could not be constructed today without significant risk. However, good progress is being made in fusion technology and, although success in magnetic fusion science and engineering is hard to predict with assurance, it seems possible that the physics basis and much of the needed technology could be demonstrated in facilities now under construction. Most of the remaining technology could be demonstrated in the early 1990s in a fusion test reactor of a few tens of megawatts. If the Magnetic Fusion Energy Program constructs a fusion test reactor of approximately 400 MW of fusion power as a next step in fusion power development, such a facility could be used later as a production reactor in a spinoff application. A construction decision in the late 1980s could result in an operating production reactor in the late 1990s. A magnetic fusion production reactor (MFPR) has four potential advantages over a fission production reactor: (1) no fissile material input is needed; (2) no fissioning exists in the tritium mode and very low fissioning exists in the plutonium mode thus avoiding the meltdown hazard; (3) the cost will probably be lower because of the smaller thermal power required; (4) and no reprocessing plant is needed in the tritium mode. The MFPR also has two disadvantages: (1) it will be more costly to operate because it consumes rather than sells electricity, and (2) there is a risk of not meeting the design goals.

Moir, R. W.

1986-12-01

53

Lactic Acid Production in a Mixed-Culture Biofilm Reactor †  

PubMed Central

Novel solid supports, consisting of polypropylene blended with various agricultural materials (pp composite), were evaluated as supports for pure- and mixed-culture continuous lactic acid fermentations in biofilm reactors. Streptomyces viridosporus T7A (ATCC 39115) was used to form a biofilm, and Lactobacillus casei subsp. rhamnosus (ATCC 11443) was used for lactic acid production. For mixed-culture fermentations, a 15-day continuous fermentation of S. viridosporus was performed initially to establish the biofilm. The culture medium was then inoculated with L. casei subsp. rhamnosus. For pure-culture fermentation, L. casei subsp. rhamnosus was inoculated directly into the reactors containing sterile pp composite chips. The biofilm reactors containing various pp composite chips were compared with a biofilm reactor containing pure polypropylene chips and with a reactor containing a suspension culture. Continuous fermentation was started, and each flow rate (0.06 to 1.92 ml/min) was held constant for 24 h; steady state was achieved after 10 h. Lactic acid production was determined throughout the 24-h period by high-performance liquid chromatography. Production rates that were two to five times faster than those of the suspension culture (control) were observed for the pure- and mixed-culture bioreactors. Both lactic acid production rates and lactic acid concentrations in the culture medium were consistently higher in mixed-culture than in pure-culture fermentations. Biofilm formation on the chips was detected at harvest by chip clumping and Gram staining.

Demirci, Ali; Pometto, Anthony L.; Johnson, Kenneth E.

1993-01-01

54

Recharge to the North Richland well field  

SciTech Connect

The investigation was based on a preliminary ground-water flow model of the 1100 Area. Because few local data were available for this effort, an existing regional ground-water flow model of the Hanford Site was applied, which is based on the Variable Thickness Transient (VTT) ground-water flow code (Kipp et al., 1976). A submodel of the Hanford Site model was developed based on the VTT code. An independent model consisting of a simple representation of the local conditions in the vicinity of the North Richland well field was also used in the investigation. This model, based on the MODFLOW code (McDonald and Harbaugh, 1984), was used in a series of transient simulations to examine dynamic aspects of the well field/recharge basin. Results from this simple model also provide an independent, qualitative check of results produced with the 1100 Area model based on the VTT code. This report summarizes the 1100 Area modeling investigation, including the approach used to generate results for the regional and 1100 Area VTT models, the approach used in the transient MODFLOW model, results from some initial steady-state and transient simulations with the submodel and the MODFLOW models, and resulting conclusions and recommendations. Because local data were lacking to develop and calibrate the models, the investigation described in this report can best be described as a ''sensitivity analysis'' of ground-water flow in the 1100 Area. 4 refs., 10 figs., 2 tabs.

Law, A.G.

1989-07-01

55

NOVEL REACTOR FOR THE PRODUCTION OF SYNTHESIS GAS  

SciTech Connect

Praxair investigated an advanced technology for producing synthesis gas from natural gas and oxygen This production process combined the use of a short-reaction time catalyst with Praxair's gas mixing technology to provide a novel reactor system. The program achieved all of the milestones contained in the development plan for Phase I. We were able to develop a reactor configuration that was able to operate at high pressures (up to 19atm). This new reactor technology was used as the basis for a new process for the conversion of natural gas to liquid products (Gas to Liquids or GTL). Economic analysis indicated that the new process could provide a 8-10% cost advantage over conventional technology. The economic prediction although favorable was not encouraging enough for a high risk program like this. Praxair decided to terminate development.

Vasilis Papavassiliou; Leo Bonnell; Dion Vlachos

2004-12-01

56

Transmutation of selected fission products in a fast reactor  

SciTech Connect

A small fast reactor such as the Fast Flux Test Facility can be an effective device for destroying long-lived fission products such as {sup 99}Tc and {sup 129}I. There are several potential core configuration options using both fast and moderated neutron spectra. The calculated Doppler reactivity coefficient for {sup 99}Tc was 60% of the value for {sup 238}U on a per atom basis. Replacing {sup 238}U with {sup 99}Tc in waste burn applications has the positive attributes of reduced parasitic capture in uranium and enhanced fission product destruction, while retaining a substantial Doppler effect. A modular liquid metal reactor system could support about 8 to 10 comparably sized conventional light water reactors.

Wootan, D.W.; Nelson, J.V.

1993-05-01

57

CALIFORNIUM PRODUCTION IN THE HIGH FLUX ISOTOPE REACTOR  

Microsoft Academic Search

Californium-252 and other isotope production rates resulting from ; irradiating Pu-242 in the proposed High Flux Isotope Reactor were estimated. The ; effect of curium recycle was investigated and optimum irradiation cycles ; determined. Approximately 60 mg of Cf-252 would be available from the HFIR ; installation about 11\\/4 years after exposure of 200 g of Pu-242 is started. The

H. C. Claiborne; M. P. Lietzke

1959-01-01

58

A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL  

Microsoft Academic Search

Gas Technology Institute is developing a novel concept of membrane gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening,

Shain Doong; Estela Ong; Mike Atroshenko; Mike Roberts; Francis Lau

2004-01-01

59

A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL  

Microsoft Academic Search

Gas Technology Institute is developing a novel concept of membrane gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening,

Shain Doong; Estela Ong; Mike Atroshenko; Francis Lau; Mike Roberts

2004-01-01

60

A microBio reactor for hydrogen production.  

SciTech Connect

The purpose of this work was to explore the potential of developing a microfluidic reactor capable of enzymatically converting glucose and other carbohydrates to hydrogen. This aggressive project was motivated by work in enzymatic hydrogen production done by Woodward et al. at OWL. The work reported here demonstrated that hydrogen could be produced from the enzymatic oxidation of glucose. Attempts at immobilizing the enzymes resulted in reduced hydrogen production rates, probably due to buffer compatibility issues. A novel in-line sensor was also developed to monitor hydrogen production in real time at levels below 1 ppm. Finally, a theoretical design for the microfluidic reactor was developed but never produced due to the low production rates of hydrogen from the immobilized enzymes. However, this work demonstrated the potential of mimicking biological systems to create energy on the microscale.

Volponi, Joanne V.; Walker, Andrew William

2003-12-01

61

192. View of the Richland Balsam Mountain Overlook. This is ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

192. View of the Richland Balsam Mountain Overlook. This is the highest elevation, 6,047, on the Blue Ridge Parkway. Looking west-northwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

62

Richland Environmental Restoration Project management action process document  

SciTech Connect

This document is the prescribed means for providing direct input to the US Department of Energy Headquarters regarding the status, accomplishments, strategy, and issues of the Richland Environmental Restoration Project. The project mission, organizational interfaces, and operational history of the Hanford Site are provided. Remediation strategies are analyzed in detail. The document includes a status of Richland Environmental Restoration project activities and accomplishments, and it presents current cost summaries, schedules, and technical baselines.

NONE

1996-04-01

63

CONTINUOUS PRODUCTION OF ETHANOL IN HIGH PRODUCTIVITY BIOREACTORS USING GENETICALLY ENGINEERED ESCHERICHIA COLI FBR5: MEMBRANE AND FIXED CELL REACTORS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Biochemical reactor design plays a major role in determining the economics of fuel and chemical production. Reactors that result in continuously high productivities can significantly reduce the cost of the final product. With this aim, five different reactor systems were evaluated for ethanol prod...

64

A proposed standard on medical isotope production in fission reactors  

SciTech Connect

Authors Robert E. Sehenter, Garry Brown and Charles S. Holden argue that a Standard for 'Medical Isotope Production' is needed. Medical isotopes are becoming major components of application for the diagnosis and treatment of all the major diseases including all forms of cancer, heart disease, arthritis, Alzheimer's, among others. Current nuclear data to perform calculations is incomplete, dated or imprecise or otherwise flawed for many isotopes that could have significant applications in medicine. Improved data files will assist computational analyses to design means and methods for improved isotope production techniques in the fission reactor systems. Initial focus of the Standard is expected to be on neutron cross section and branching data for both fast and thermal reactor systems. Evaluated and reviewed tables giving thermal capture cross sections and resonance integrals for the major target and product medical isotopes would be the expected 'first start' for the 'Standard Working Group'. (authors)

Schenter, R. E. [Smart Bullets Inc., 2521 SW Luradel Street, Portland, OR 97219 (United States); Brown, G. J. [Ozarks Medical Center, Cancer Treatment Center, Shaw Medical Building, 1111 Kentucky Avenue, West Plains, MO 65775 (United States); Holden, C. S. [Thorenco LLC, 369 Pine Street, San Francisco, CA 94104 (United States)

2006-07-01

65

Production of long-lived hafnium isomers in reactor irradiations  

NASA Astrophysics Data System (ADS)

Experiments on production of long-lived Hf178m isomer in reactor irradiations are described. Properties of this nuclide are promising for its potential application as a relatively safe power source characterized by high density of accumulated energy. Metal natHf samples were activated in the Dubna IBR-2 reactor at positions corresponding to different neutron fluxes. Samples were bare or shielded by Cd and B 4C layers. The gamma activity of the samples was analyzed with Ge gamma spectrometers during a two-year period following their irradiation. In the presence of dominant activation products 175Hf and 181Hf, the high-spin isomers Hf178m and Hf179m were also detected despite relatively low levels. The isomer-to-ground state ratios and cross-sections were determined from the measured yields. For Hf178m, the cross-section for burnup (destruction) by neutron capture after its production was also estimated, clarifying the results from earlier experiments. In the context of suggestions for use of Hf178m for applications, the results confirm that large-scale production of this isomer by reactor irradiations is not feasible. In contrast, the efficiency of production of Hf179m is much higher and an amount of about 10 16 atoms may be produced in standard reactor irradiations. For Hf178m, more productive methods are known, in particular fast neutron irradiations at E n ? 14 MeV and spallation reactions at intermediate energies. Neutron cross-sections for isomers may also be significant in astrophysics.

Karamian, S. A.; Carroll, J. J.; Adam, J.; Kulagin, E. N.; Shabalin, E. P.

2006-06-01

66

Standards data base for the Department of Energy (DOE) Office of New Production Reactors (ONPR).  

National Technical Information Service (NTIS)

The DOE Office of New Production Reactors (ONPR) has the overall responsibility and authority to manage the development, design, construction, and initial operation of the next generation of production reactors and associated fuel and target cycle support...

P. R. Lobner W. L. Cooper

1989-01-01

67

A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL  

SciTech Connect

Gas Technology Institute is developing a novel concept of membrane reactor coupled with a gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening, testing and identifying potential candidate membranes under high temperature, high pressure, and harsh environments of the coal gasification conditions. The best performing membranes will be selected for preliminary reactor design and cost estimates. Hydrogen permeation data for several perovskite membranes BCN (BaCe{sub 0.9}Nd{sub 0.1}O{sub 3-x}), SCE (SrCe{sub 0.9}Eu{sub 0.1}O{sub 3}) and SCTm (SrCe{sub 0.95}Tm{sub 0.05}O{sub 3}) have been successfully obtained for temperatures between 800 and 950 C and pressures from 1 to 12 bar in this project. However, it is known that the cerate-based perovskite materials can react with CO{sub 2}. Therefore, the stability issue of the proton conducting perovskite materials under CO{sub 2} or H{sub 2}S environments was examined. Tests were conducted in the Thermo Gravimetric Analyzer (TGA) unit for powder and disk forms of BCN and SCE. Perovskite materials doped with zirconium (Zr) are known to be resistant to CO{sub 2}. The results from the evaluation of the chemical stability for the Zr doped perovskite membranes are presented. During this reporting period, flowsheet simulation was also performed to calculate material and energy balance based on several hydrogen production processes from coal using high temperature membrane reactor (1000 C), low temperature membrane reactor (250 C), or conventional technologies. The results show that the coal to hydrogen process employing both the high temperature and the low temperature membrane reactors can increase the hydrogen production efficiency (cold gas efficiency) by more than 50% compared to the conventional process. Using either high temperature or low temperature membrane reactor process also results in an increase of the cold gas efficiencies as well as the thermal efficiencies of the overall process.

Shain Doong; Estela Ong; Mike Atroshenko; Francis Lau; Mike Roberts

2005-07-29

68

An evaluation of reactor cooling and coupled hydrogen production processes using the modular helium reactor  

Microsoft Academic Search

The high-temperature characteristics of the modular helium reactor (MHR) make it a strong candidate for producing hydrogen using either thermochemical or high-temperature electrolysis (HTE) processes. Using heat from the MHR to drive a sulfur-iodine (SI) thermochemical hydrogen production process has been the subject of a U.S. Department of Energy sponsored Nuclear Engineering Research Initiative (NERI) project led by General Atomics,

E. A. Harvego; S. M. M. Reza; M. Richards; A. Shenoy

2006-01-01

69

Two photons correlated production at the 25MWTh reactor  

Microsoft Academic Search

We have performed an extensive search for correlated production of two or more photons at the 25MWTh reactor at Swierk\\/Poland\\/. We were looking for a prompt signal originating from decays of axions. Our experimental set-up consisted of an arry of nine 3`×3` NaI\\/Tl\\/detectors, surrounded by active\\/plastic scintillators\\/ and passive shieldings, thus ncreasing experimental sensitivity as compared to other experiments in

H. Abramowicz; K. Doroba; R. Walczak; M. Górski; A. Jasin-acute-accentski; T. Kozl-dash-barowski; W. Ratyn-acute-accentski; M. Szeptycka; M. Szymczak; A. Tucholski

1985-01-01

70

Solar water splitting for hydrogen production with monolithic reactors  

Microsoft Academic Search

The present work proposes the exploitation of solar energy for the dissociation of water and production of hydrogen via an integrated thermo-chemical reactor\\/receiver system. The basic idea is the use of multi-channelled honeycomb ceramic supports coated with active redox reagent powders, in a configuration similar to that encountered in automobile exhaust catalytic aftertreatment.Iron-oxide-based redox materials were synthesized, capable to operate

C. Agrafiotis; M. Roeb; A. G. Konstandopoulos; L. Nalbandian; V. T. Zaspalis; C. Sattler; P. Stobbe; A. M. Steele

2005-01-01

71

A new tubular reactor for mass production of microalgae outdoors  

Microsoft Academic Search

A novel reactor for outdoor production of microalgae is described. Air-lift is used for circulation of the culture in transparent tubes lying on the ground and interconnected by a manifold. Dissolved O2 is removed through a gas-separator placed 2.0 m above the tubes and water-spray is used for cooling. The manifold permits short-run durations between leaving the gas separator and

Amos Richmond; Sammy Boussiba; Avigad Vonshak; Reuven Kopel

1993-01-01

72

Corrosion-product release in light water reactors  

SciTech Connect

This is the final report of a research program aimed at measuring and studying the release of corrosion products from typical PWR and BWR materials to reactor coolant. The program has provided measurements of release from stainless steel, steam generator alloys and hard-facing material (Stellite) to PWR coolant under several chemistry conditions. Kinetic expressions for cumulative release as a function of time have been developed. Corrosion measurements in- and out-reactor have indicated little effect of reactor radiation on corrosion of these materials. Detailed surface analysis has characterized the formation of oxide films in PWR coolant, and has led to suggestions of mechanisms of release. The mechanisms have been made the basis of a system model which has been used to evaluate the effects of various system parameters on the concentration of dissolved cobalt in the coolant--i.e., on the source term for activity transport. The understanding of film formation and release have led to a proposed method of preconditioning PWRs to reduce substantially radiation fields during subsequent operation. Correlations for elemental release from stainless steel and Stellite under BWR conditions have also been derived. They indicate that cobalt-based alloys in BWR reactor circuits are the major source of corrosion-released cobalt. The effects of zinc on the growth of oxide films on carbon steel, Inconel-600 and Stellite-6 are also described. 39 refs., 38 figs., 12 tabs.

Lister, D.; Davidson, R.D. (Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.)

1989-09-01

73

Design Study and Analysis of Pb-Bi Cooled Fast Reactor for Hydrogen Production  

Microsoft Academic Search

DESIGN STUDY AND ANALYSIS OF PB-BI COOLED FAST REACTOR FOR HYDROGEN PRODUCTION. The capability of 200 MWt Pb-Bi cooled fast reactor to operate at average coolant outlet temperature 550 0C and satisfy safety requirement give an opportunity this reactor as a heat source for hydrogen production. In this study 200 MWt Pb-Bi cooled fast reactor for hydrogen production have been

Zaki Su' ud; Abdul Waris; Bambang Ari Wahjoedi; Bandar Seri Iskandar; Perak Darul Ridzuan

74

Biological hydrogen production in a UASB reactor with granules. II: Reactor performance in 3-year operation.  

PubMed

The experiment was conducted to evaluate the performance of an upflow anaerobic sludge blanket (UASB) with granules for H(2) production from a sucrose-rich synthetic wastewater at various substrate concentrations (5.33-28.07 g-COD/L) and hydraulic retention times (HRTs) (3-30 h) for over 3 years. The kinetics of H(2) production was evaluated, and the sludge yield and endogenous decay coefficient of the H(2)-producing granules were estimated to be 0.334 g-VSS/g-COD and 0.004/h, respectively. Based on Gibbs free energy calculations, the formation thermodynamics of caproate, an important aqueous product, were analyzed. Experimental results show that the H(2) partial pressure in biogas decreased with increasing substrate concentration, but was not sensitive to the variation of HRT in a range of 6-22 h. The H(2) production rate increased with increasing substrate concentration, but decreased with increasing HRT. The H(2) yield was in the range of 0.49-1.44 mol-H(2)/mol-glucose. Acetate, butyrate, caporate, and ethanol were the main aqueous products in the reactor, and their concentrations were dependent on both substrate concentration and HRT. An elevated substrate concentration resulted in a shift of fermentation from butyrate- to caporate-type in the reactor and the formation of caproate was dependent on the H(2) partial pressure. The 3-year experimental results demonstrate that H(2) could be produced continuously and stably from the acidogenic-granule-based UASB reactor. PMID:16615161

Yu, Han-Qing; Mu, Yang

2006-08-01

75

Process aspects of hydrogen production using the Tandem Mirror Reactor  

SciTech Connect

An SO/sub 3/ decomposer design is presented which provides the necessary production of SO/sub 2/ + O/sub 2/ for the thermochemical production of H/sub 2/ using the thermal heat from the blanket of a Tandem Mirror Fusion Reactor. The decomposer is a catalytic, fluidized bed reactor operating at 1050/sup 0/K that contains internal heat exchanger tubes to provide the heat for the highly endothermic SO/sub 3/ decomposition reactor. The conversion per pass is around 55% using either CuO or platinum-based catalysts. We examine the impact on the design of varying the temperature 100/sup 0/C higher or lower than 1050/sup 0/K and we also look at both liquid sodium and helium as the heat transfer medium to carry the heat from the TMR to the decomposer. To drive a H/sub 2/ plant with 15 x 10/sup 6/ sm/sup 3//d there would be around 7 decomposers, 10 m in height and 6 m in diameter, made of Incoloy-800H at $24/kg at a total capital cost of around $50 million - which translates to about 12 cents/GJ of H/sub 2/ produced with conventional economics. Helium-driven units would approximately double the cost in trade for the additional safety isolation.

Galloway, T.R.

1980-10-08

76

Preconceptual design of the new production reactor circulator test facility  

SciTech Connect

This report presents the results of a study of a new circulator test facility for the New Production Reactor Modular High-Temperature Gas-Cooled Reactor. The report addresses the preconceptual design of a stand-alone test facility with all the required equipment to test the Main Circulator/shutoff valve and Shutdown Cooling Circulator/shutoff valve. Each type of circulator will be tested in its own full flow, full power helium test loop. Testing will cover the entire operating range of each unit. The loop will include a test vessel, in which the circulator/valve will be mounted, and external piping. The external flow piping will include a throttle valve, flowmeter, and heat exchanger. Subsystems will include helium handling, helium purification, and cooling water. A computer-based data acquisition and control system will be provided. The estimated costs for the design and construction of this facility are included. 2 refs., 15 figs.

Thurston, G.

1990-06-01

77

MANHATTAN PROJECT B REACTOR HANFORD WASHINGTON [HANFORD'S HISTORIC B REACTOR (12-PAGE BOOKLET)  

SciTech Connect

The Hanford Site began as part of the United States Manhattan Project to research, test and build atomic weapons during World War II. The original 670-square mile Hanford Site, then known as the Hanford Engineer Works, was the last of three top-secret sites constructed in order to produce enriched uranium and plutonium for the world's first nuclear weapons. B Reactor, located about 45 miles northwest of Richland, Washington, is the world's first full-scale nuclear reactor. Not only was B Reactor a first-of-a-kind engineering structure, it was built and fully functional in just 11 months. Eventually, the shoreline of the Columbia River in southeastern Washington State held nine nuclear reactors at the height of Hanford's nuclear defense production during the Cold War era. The B Reactor was shut down in 1968. During the 1980's, the U.S. Department of Energy began removing B Reactor's support facilities. The reactor building, the river pumphouse and the reactor stack are the only facilities that remain. Today, the U.S. Department of Energy (DOE) Richland Operations Office offers escorted public access to B Reactor along a designated tour route. The National Park Service (NPS) is studying preservation and interpretation options for sites associated with the Manhattan Project. A draft is expected in summer 2009. A final report will recommend whether the B Reactor, along with other Manhattan Project facilities, should be preserved, and if so, what roles the DOE, the NPS and community partners will play in preservation and public education. In August 2008, the DOE announced plans to open B Reactor for additional public tours. Potential hazards still exist within the building. However, the approved tour route is safe for visitors and workers. DOE may open additional areas once it can assure public safety by mitigating hazards.

GERBER MS

2009-04-28

78

Catalyst development for microchannel reactors for martian in situ propellant production  

Microsoft Academic Search

Catalytic microchannel reactors were designed for in situ propellant production for Mars exploration. In the reactor system, the Sabatier and the reverse water–gas-shift (RWGS) reactions were carried out for methane and oxygen production using carbon dioxide and hydrogen as feed stock. The focus of the present study was on developing catalysts for these two reactions, aiming at intensifying reactor operation.

Jianli Hu; Kriston P. Brooks; Jamelyn D. Holladay; Daniel T. Howe; Thomas M. Simon

2007-01-01

79

Long-lived activation products in reactor materials  

SciTech Connect

The purpose of this program was to assess the problems posed to reactor decommissioning by long-lived activation products in reactor construction materials. Samples of stainless steel, vessel steel, concrete, and concrete ingredients were analyzed for up to 52 elements in order to develop a data base of activatable major, minor, and trace elements. Large compositional variations were noted for some elements. Cobalt and niobium concentrations in stainless steel, for example, were found to vary by more than an order of magnitude. A thorough evaluation was made of all possible nuclear reactions that could lead to long lived activation products. It was concluded that all major activation products have been satisfactorily accounted for in decommissioning planning studies completed to date. A detailed series of calculations was carried out using average values of the measured compositions of the appropriate materials to predict the levels of activation products expected in reactor internals, vessel walls, and bioshield materials for PWR and BWR geometries. A comparison is made between calculated activation levels and regulatory guidelines for shallow land disposal according to 10 CFR 61. This analysis shows that PWR and BWR shroud material exceeds the Class C limits and is, therefore, generally unsuitable for near-surface disposal. The PWR core barrel material approaches the Class C limits. Most of the remaining massive components qualify as either Class A or B waste with the bioshield clearly Class A, even at the highest point of activation. Selected samples of activated steel and concrete were subjected to a limited radiochemical analysis program as a verification of the computer model. Reasonably good agreement with the calculations was obtained where comparison was possible. In particular, the presence of /sup 94/Nb in activated stainless steel at or somewhat above expected levels was confirmed.

Evans, J.C.; Lepel, E.L.; Sanders, R.W.; Wilkerson, C.L.; Silker, W.; Thomas, C.W.; Abel, K.H.; Robertson, D.R.

1984-08-01

80

Biological production of ethanol from coal. Task 4 report, Continuous reactor studies.  

National Technical Information Service (NTIS)

The production of ethanol from synthesis gas by the anaerobic bacterium C. ljungdahlii has been demonstrated in continuous stirred tank reactors (CSTRs), CSTRs with cell recycle and trickle bed reactors. Various liquid media were utilized in these studies...

1992-01-01

81

Reactor design for minimizing product inhibition during enzymatic lignocellulose hydrolysis: II. Quantification of inhibition and suitability of membrane reactors.  

PubMed

Product inhibition of cellulolytic enzymes affects the efficiency of the biocatalytic conversion of lignocellulosic biomass to ethanol and other valuable products. New strategies that focus on reactor designs encompassing product removal, notably glucose removal, during enzymatic cellulose conversion are required for alleviation of glucose product inhibition. Supported by numerous calculations this review assesses the quantitative aspects of glucose product inhibition on enzyme-catalyzed cellulose degradation rates. The significance of glucose product inhibition on dimensioning of different ideal reactor types, i.e. batch, continuous stirred, and plug-flow, is illustrated quantitatively by modeling different extents of cellulose conversion at different reaction conditions. The main operational challenges of membrane reactors for lignocellulose conversion are highlighted. Key membrane reactor features, including system set-up, dilution rate, glucose output profile, and the problem of cellobiose are examined to illustrate the quantitative significance of the glucose product inhibition and the total glucose concentration on the cellulolytic conversion rate. Comprehensive overviews of the available literature data for glucose removal by membranes and for cellulose enzyme stability in membrane reactors are given. The treatise clearly shows that membrane reactors allowing continuous, complete, glucose removal during enzymatic cellulose hydrolysis, can provide for both higher cellulose hydrolysis rates and higher enzyme usage efficiency (kg(product)/kg(enzyme)). Current membrane reactor designs are however not feasible for large scale operations. The report emphasizes that the industrial realization of cellulosic ethanol requires more focus on the operational feasibility within the different hydrolysis reactor designs, notably for membrane reactors, to achieve efficient enzyme-catalyzed cellulose degradation. PMID:20172020

Andri?, Pavle; Meyer, Anne S; Jensen, Peter A; Dam-Johansen, Kim

2010-02-19

82

CFD optimization of continuous stirred-tank (CSTR) reactor for biohydrogen production  

Microsoft Academic Search

There has been little work on the optimal configuration of biohydrogen production reactors. This paper describes three-dimensional computational fluid dynamics (CFD) simulations of gas–liquid flow in a laboratory-scale continuous stirred-tank reactor used for biohydrogen production. To evaluate the role of hydrodynamics in reactor design and optimize the reactor configuration, an optimized impeller design has been constructed and validated with CFD

Jie Ding; Xu Wang; Xue-Fei Zhou; Nan-Qi Ren; Wan-Qian Guo

2010-01-01

83

Westinghouse independent safety review of Savannah River production reactors  

SciTech Connect

Westinghouse Electric Corporation has performed a safety assessment of the Savannah River production reactors (K,L, and P) as requested by the US Department of Energy. This assessment was performed between November 1, 1988, and April 1, 1989, under the transition contract for the Westinghouse Savannah River Company's preparations to succeed E.I. du Pont de Nemours Company as the US Department of Energy contractor for the Savannah River Project. The reviewers were drawn from several Westinghouse nuclear energy organizations, embody a combination of commercial and government reactor experience, and have backgrounds covering the range of technologies relevant to assessing nuclear safety. The report presents the rationale from which the overall judgment was drawn and the basis for the committee's opinion on the phased restart strategy proposed by E.I. du Pont de Nemours Company, Westinghouse, and the US Department of Energy-Savannah River. The committee concluded that it could recommend restart of one reactor at partial power upon completion of a list of recommended upgrades both to systems and their supporting analyses and after demonstration that the organization had assimilated the massive changes it will have undergone.

Leggett, W.D.; McShane, W.J. (Westinghouse Hanford Co., Richland, WA (USA)); Liparulo, N.J.; McAdoo, J.D.; Strawbridge, L.E. (Westinghouse Electric Corp., Pittsburgh, PA (USA). Nuclear and Advanced Technology Div.); Toto, G. (Westinghouse Electric Corp., Pittsburgh, PA (USA). Nuclear Services Div.); Fauske, H.K. (Fauske and Associates, Inc., Burr Ridge, IL (USA)); Call, D.W. (Westinghouse Savannah R

1989-04-01

84

Solar chemical reactor technology for industrial production of lime  

Microsoft Academic Search

We developed the solar chemical reactor technology to effect the endothermic calcination reaction CaCO3(s)?CaO(s)+CO2(g) at 1200–1400K. The indirect heating 10kWth multi-tube rotary kiln prototype processed 1–5mm limestone particles, producing high purity lime that is not contaminated with combustion by-products. The quality of the solar produced quicklime meets highest industrial standards in terms of reactivity (low, medium, and high) and degree

Anton Meier; Enrico Bonaldi; Gian Mario Cella; Wojciech Lipinski; Daniel Wuillemin

2006-01-01

85

A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL  

SciTech Connect

Gas Technology Institute is developing a novel concept of membrane gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening, testing and identifying potential candidate membranes under high temperature, high pressure, and harsh environments of the coal gasification conditions. The best performing membranes will be selected for preliminary reactor design and cost estimates. To evaluate the performances of the candidate membranes under the gasification conditions, a high temperature/high pressure hydrogen permeation unit has been constructed in this project. During this reporting period, the unit has been fully commissioned and is operational. The unit is capable of operating at temperatures up to 1100 C and pressures to 60 atm for evaluation of ceramic membranes such as mixed ionic conducting membrane. A double-seal technique has been developed and tested successfully to achieve leak-tight seal for the membranes. Initial data for a commercial Palladium-Gold membrane were obtained at temperatures to 450 C and pressures to 13 atm. Tests for the perovskite membranes are being performed and the results will be reported in the next quarter. A membrane gasification reactor model was developed to consider the H{sub 2} permeability of the membrane, the kinetics and the equilibriums of the gas phase reactions in the gasifier, the operating conditions and the configurations of the membrane reactor. The results show that the hydrogen production efficiency using the novel membrane gasification reactor concept can be increased by about 50% versus the conventional gasification process. This confirms the previous evaluation results from the thermodynamic equilibrium calculation. A rigorous model for hydrogen permeation through mixed proton-electron conducting ceramic membranes was also developed based on non-equilibrium thermodynamics. The results from the simulation work confirm that the hydrogen flux increases with increasing partial pressure of hydrogen. The presence of steam in the permeate side can have a small negative effect on the hydrogen flux, in the order of 10%. When the steam partial pressure is greater than 1 atm, the hydrogen flux becomes independent of the steam pressure.

Shain Doong; Estela Ong; Mike Atroshenko; Francis Lau; Mike Roberts

2004-07-29

86

Radionuclide production at the University of Missouri research reactor  

SciTech Connect

Reactor-produced radionuclides have wide applications in biological and biochemical research and in nuclear medicine diagnosis and therapy of disease. The University of Missouri Research Reactor (MURR) has long played a prominent role in these applications, beginning with isotope {open_quotes}seed{close_quotes} implants and (n, {gamma}) {sup 99}Mo for {sup 99m}Tc generators >25 yr ago. In the last 20 yr MURR`s radioisotope production has focused on research and development of therapeutic beta emitters such as {sup 90}Y microspheres; {sup 188}W {sup 188}Re and {sup 166} Dy/ {sup 166}Ho generators; and high-specific-activity {sup 153}Sm, {sup 186}Re, {sup 166}Ho, {sup 177}Lu, and {sup 105}Rh. Production of {sup 192}Ir and {sup 198}Au for therapeutic seeds has continued, while MURR irradiations to produce {sup 35}S, {sup 32}P, and (most recently) {sup 33}P continue to supply a significant fraction of the world`s market.

Ehrhardt, G.J.; Ketring, A.R.; Ma, D. [Univ. of Missouri, Columbia, MO (United States)

1997-12-01

87

(COMEDIE program review and fission product transport in MHTGR reactor)  

SciTech Connect

The subcontract between Martin Marietta Energy Systems, Inc., and the CEA provides for the refurbishment of the high pressure COMEDIE test loop in the SILOE reactor and a series of experiments to characterize fission product lift-off from MHTGR heat exchanger surfaces under several depressurization accident scenarios. The data will contribute to the validation of models and codes used to predict fission product transport in the MHTGR. In the meeting at CEA headquarters in Paris the program schedule and preparation for the DCAA and Quality Assurance audits were discussed. Long-range interest in expanded participation in the gas-cooled reactor technology Umbrella Agreement was also expressed by the CEA. At the CENG, in Grenoble, technical details on the loop design, fabrication components, development of test procedures, and preparation for the DOE quality assurance (QA) audit in May were discussed. After significant delays in CY 1989 it appears that good progress is being made in CY 1990 and the first major test will be initiated by December. An extensive list of agreements and commitments was generated to facilitate the coordination and planning of future work. 2 figs., 2 tabs.

Stansfield, O.M.

1990-03-15

88

Development of Enzymatic Membrane Reactor (EMR) for Cyclodextrins Production  

NASA Astrophysics Data System (ADS)

This study investigated on the fouling mechanisms in ultrafiltration membrane during separation of cyclodextrins from starch and CGTase. The Resistance-In-Series Model was used to identify the responsible hydraulic resistances. The result showed that the weak adsorption fouling resistance (ra1) was the main factor that contributed the rate and extent of flux decline. Moreover the significant organic fouling that is contributed by starch, CDs, CGTase and intermediate by-products in organic colloids and/or macromolecular revealed that the fouling potential was ra1> rg > rcp > ra2. The overall results indicate that the fouling mechanism consists of pore mouth adsorption and subsequently narrowing of the pores as those components (starch and CGTase) are small enough not to be excluded by steric considerations. In the latter stage unreacted starch would be accumulated to form gel/cake layer. The measured flux recovery of enzymatic membrane reactor for CDs production was about 95%.

Mimi Sakinah, A. M.; Ismail, A. F.; Illias, Rosli Md; Hassan, Osman

89

Butanol production by Clostridium beijerinckii BA101 in an immobilized cell biofilm reactor  

Microsoft Academic Search

Acetone butanol ethanol was produced in a continuous immobilized cell (biofilm) plug-flow reactor inoculated with Clostridium beijerinckii BA101. To achieve high reactor productivity, C. beijerinckii BA101 cells were immobilized by adsorption onto clay brick. The continuous plug-flow reactor offers high productivities owing\\u000a to reduced butanol inhibition and increased cell concentration. Although high productivity was achieved, it was at the expense

Jason Lienhardt; Justin Schripsema; Nasib Qureshi; Hans P. Blaschek

2002-01-01

90

Methanol as carbon source for biomass production in a loop reactor  

Microsoft Academic Search

Literature concerning mass transfer in bubble columns and loop reactors contains numerous data on small-scale units. On the other hand, data on the production scale, i.e. reactor diameters exceeding 1 m, are scarce. The present work tries to apply the data that are available to the calculation of a loop reactor. The metabolic reaction itself is performed in each single

U. Faust; W. Sittig

91

High temperature growth of SiC and group III nitride structures in production reactors  

Microsoft Academic Search

We describe the use of a family of high temperature reactors to grow SiC and nitrides. The load capacity ranges from single wafer machines to multiple wafer mass production reactors. All these reactors have a two flow injection system allowing a separated inlet of the various reactants. To achieve maximum uniformity of the growth, the gas foil rotation principle is

D. Schmitz; R. Beccard; G. Strauch; H. Juergensen; E. Woelk; M. Bremser

1998-01-01

92

Bio-hydrogen production from molasses by anaerobic fermentation in continuous stirred tank reactor  

NASA Astrophysics Data System (ADS)

A study of bio-hydrogen production was performed in a continuous flow anaerobic fermentation reactor (with an available volume of 5.4 L). The continuous stirred tank reactor (CSTR) for bio-hydrogen production was operated under the organic loading rates (OLR) of 8-32 kg COD/m3 reactor/d (COD: chemical oxygen demand) with molasses as the substrate. The maximum hydrogen production yield of 8.19 L/d was obtained in the reactor with the OLR increased from 8 kg COD/m3 reactor/d to 24 kg COD/m3 d. However, the hydrogen production and volatile fatty acids (VFAs) drastically decreased at an OLR of 32 kg COD/m3 reactor/d. Ethanoi, acetic, butyric and propionic were the main liquid fermentation products with the percentages of 31%, 24%, 20% and 18%, which formed the mixed-type fermentation.

Han, Wei; Li, Yong-Feng; Chen, Hong; Deng, Jie-Xuan; Yang, Chuan-Ping

2010-11-01

93

Methanol production in an optimized dual-membrane fixed-bed reactor  

Microsoft Academic Search

Coupling reaction and separation in a membrane reactor improves the reactor efficiency and reduces purification cost in the following stages. This paper focuses on modeling and optimization of methanol production in a dual-membrane reactor. In this configuration, conventional methanol reactor is supported by Pd\\/Ag membrane tubes for hydrogen permeation and alumina–silica composite membrane tubes for water vapor removal from the

M. Farsi; A. Jahanmiri

94

Annual Energy Consumption Analysis Report for Richland Middle School  

SciTech Connect

Richland Middle School is a single story, 90,000 square feet new school located in Richland, WA. The design team proposed four HVAC system options to serve the building. The proposed HVAC systems are listed as following: (1) 4-pipe fan coil units served by electrical chiller and gas-fired boilers, (2) Ground-source closed water loop heat pumps with water loop heat pumps with boiler and cooling tower, and (3) VAV system served by electrical chiller and gas-fired boiler. This analysis estimates the annual energy consumptions and costs of each system option, in order to provide the design team with a reasonable basis for determining which system is most life-cycle cost effective. eQuest (version 3.37), a computer-based energy simulation program that uses the DOE-2 simulation engine, was used to estimate the annual energy costs.

Liu, Bing

2003-12-18

95

A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL  

SciTech Connect

Gas Technology Institute is developing a novel concept of membrane gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening, testing and identifying potential candidate membranes under high temperature, high pressure, and harsh environments of the coal gasification conditions. The best performing membranes will be selected for preliminary reactor design and cost estimates. To evaluate the performances of the candidate membranes under the gasification conditions, a high temperature/high pressure hydrogen permeation unit has been constructed in this project. The unit is designed to operate at temperatures up to 1100 C and pressures to 60 atm for evaluation of ceramic membranes such as mixed ionic conducting membrane. The unit was fully commissioned and is operational. Several perovskite membranes based on the formulations of BCN (BaCe{sub 0.8}Nd{sub 0.2}O{sub 3-x}) and BCY (BaCe{sub 0.8}Y{sub 0.2}O{sub 3-x}) were prepared by GTI and tested in the new permeation unit. These membranes were fabricated by either uniaxial pressing or tape casting technique with thickness ranging from 0.2 mm to 0.7 mm. Hydrogen permeation data for the BCN perovskite membrane have been successfully obtained for temperatures between 800 and 950 C and pressures from 1 to 12 bar. The highest hydrogen flux was measured at 1.6 STPcc/min/cm{sup 2} at a hydrogen feed pressure of 12 bar and 950 C with a membrane thickness of 0.22 mm. A membrane gasification reactor model was developed to consider the H{sub 2} permeability of the membrane, the kinetics and the equilibriums of the gas phase reactions in the gasifier, the operating conditions and the configurations of the membrane reactor. The results show that the hydrogen production efficiency using the novel membrane gasification reactor concept can be increased by about 50% versus the conventional gasification process. This confirms the previous evaluation results from the thermodynamic equilibrium calculation. A rigorous model for hydrogen permeation through mixed proton-electron conducting ceramic membranes was also developed based on non-equilibrium thermodynamics. The hydrogen flux predicted from the modeling results are in line with the data from the experimental measurement. The simulation also shows that the presence of steam in the permeate side or the feed side of the membrane can have a small negative effect on the hydrogen flux, in the order of 10%.

Shain Doong; Estela Ong; Mike Atroshenko; Francis Lau; Mike Roberts

2004-10-26

96

Wetlands: Their impact on siting a proposed nuclear production reactor  

SciTech Connect

The Savannah River Site (SRS) is a 780-km[sup 2] US Department of Energy (DOE) site managed by the Westinghouse Savannah River Company for the production of nuclear materials for defense and other purposes. Five nuclear production reactors (NPRs) constructed in the 1950s are located on the site, and all but one are either on standby or shut down. The possibility of siting a new NPR at the SRS or at other sites (Hanford and Idaho) in the DOE complex was being evaluated in an environmental impact statement (EIS) when on November 1, 1991, the Secretary of Energy decided to defer a decision on the NPR until after a programmatic EIS addressing reconfiguration of the DOE weapons complex was completed. Candidate sites at SRS for the proposed NPR were evaluated against disqualifying conditions in the categories of ecological resources and wetlands, human health effects, geology/hydrology, and engineering considerations. In initial considerations, the presence of wetlands was not determined to be a disqualifying condition. It was critical that the proposed reactor be sited on an area with optimum geologic properties so that the required load-bearing capacity under its footprint could be met. Lessons learned in this planning effort are to clearly understand the real needs of the project in terms of area, hydrology, geologic criteria, etc., and conduct siting studies early in a project's life that strongly weigh wetlands and other ecological considerations. In this case, once project personnel had a clear understanding of the length of time required for processing the Sec. 404 permit (and possibly a Sec. 10 permit for the outfall) and the cost required for preparation of the permit application, mitigation, and long-term monitoring, the site selection criteria were revisited. After numerous discussions and additional geologic considerations, it was determined that the proposed NPR footprint could be oriented to avoid all but [approximately]0.5ha of wetlands.

Hooker, K.L.; Danker, S.A.; Grainger, A.R. (Savannah River Operations Office, Aiken, SC (United States)); Rogers, V.A.

1993-01-01

97

Pipe break testing of primary loop piping similar to Department of Energy's New Production Reactor-Heavy Water Reactor  

SciTech Connect

The subject of this paper is to review the recent failure testing of the Savannah River C-reactor piping weldment, which will be referred to as the C-pipe in the remainder of the paper. The intent of this paper is to further familiarize the technical community with Oak Ridge National Laboratory's (ORNL) pipe test program and associated activities surrounding the C-pipe test as conducted on behalf of the Department of Energy New Production Reactor (DOE-NPR) Program.

Poole, A.B.; Clinard, J.A.; Battiste, R.L.; Hendrich, W.R.

1993-01-01

98

Comparative study of ethanol production by an immobilized yeast in a tubular reactor and in a multistage reactor  

Microsoft Academic Search

Summary The productivity of continuous ethanol fermentation has been increased using fixed bed reactors where a high density of yeast cells was maintained on a packing of wood chips. Two different systems have been used: 1. A tubular reactor which produced alcohol solutions containing up to 13.5% (V\\/V) ethanol. High CO2 retention and a poor mass transfer between bulk medium

Y. W. Ryu; J. M. Navarro; G. Durand

1982-01-01

99

Uncertainties in the Anti-neutrino Production at Nuclear Reactors  

SciTech Connect

Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in {bar {nu}}{sub e} detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties, and their relevance to reactor {bar {nu}}{sub e} experiments.

Djurcic, Zelimir; Detwiler, Jason A.; Piepke, Andreas; Foster Jr., Vince R.; Miller, Lester; Gratta, Giorgio

2008-08-06

100

Production capabilities in US nuclear reactors for medical radioisotopes  

Microsoft Academic Search

The availability of reactor-produced radioisotopes in the United States for use in medical research and nuclear medicine has traditionally depended on facilities which are an integral part of the US national laboratories and a few reactors at universities. One exception is the reactor in Sterling Forest, New York, originally operated as part of the Cintichem (Union Carbide) system, which is

S. Mirzadeh; A. P. Callahan; F. F. Jr. Knapp; R. E. Schenter

1992-01-01

101

Synthesis gas production by biomass pyrolysis: Effect of reactor temperature on product distribution  

Microsoft Academic Search

This paper describes mass, C, H, and O balances for wood chips pyrolysis experiments performed in a tubular reactor under conditions of rich H2 gas production (700–1000°C) and for determined solid heating rates (20–40°Cs?1). Permanent gases (H2, CO, CH4, CO2, C2H4, C2H6), water, aromatic tar (10 compounds from benzene to phenanthrene and phenols), and char were considered in the balance

A. Dufour; P. Girods; E. Masson; Y. Rogaume; A. Zoulalian

2009-01-01

102

A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL  

SciTech Connect

Gas Technology Institute is developing a novel concept of membrane reactor coupled with a gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening, testing and identifying potential candidate membranes under high temperature, high pressure, and harsh environments of the coal gasification conditions. The best performing membranes will be selected for preliminary reactor design and cost estimates. To evaluate the performances of the candidate membranes under the gasification conditions, a high temperature/high pressure hydrogen permeation unit has been constructed in this project. The unit is designed to operate at temperatures up to 1100 C and pressures to 60 atm for evaluation of ceramic membranes such as mixed protonic-electronic conducting membrane. Several perovskite membranes based on the formulations of BCN (BaCe{sub 0.8}Nd{sub 0.2}O{sub 3-x}), BCY (BaCe{sub 0.8}Y{sub 0.2}O{sub 3-x}), Eu-doped SrCeO{sub 3} (SCE) and SrCe{sub 0.95}Tm{sub 0.05}O{sub 3} (SCTm) were successfully tested in the new permeation unit. During this reporting period, a thin BCN membrane supported on a porous BCN layer was fabricated. The objective was to increase the hydrogen flux with a further reduction of the thickness of the active membrane layer. The thinnest dense layer that could be achieved in our laboratory currently was about 0.2 mm. Nevertheless, the membrane was tested in the permeation unit and showed reasonable flux compared to the previous BCN samples of the same thickness. A long term durability test was conducted for a SCTm membrane with pure hydrogen in the feed side and nitrogen in the sweep side. The pressure was 1 bar and the temperature was around 1010 C. No decline of hydrogen flux was observed after continuous running of over 250 hours. This long term test indicates that the perovskite membrane has good thermal stability under the reducing conditions of the hydrogen atmosphere. A conceptual design of the membrane reactor configuration for a 1000 tons-per-day (TPD) coal gasifier was completed. The design considered a tubular membrane module located within the freeboard area of a fluidized bed gasifier. The membrane ambipolar conductivity was based on the value calculated from the measured permeation data. A membrane thickness of 25 micron was assumed in the calculation. The GTI's gasification model combined with a membrane reactor model were used to determine the dimensions of the membrane module. It appears that a membrane module can be configured within a fluidized bed gasifier without substantial increase of the gasifier dimensions.

Shain Doong; Estela Ong; Mike Atroshenko; Francis Lau; Mike Roberts

2005-04-28

103

Utilization of fast reactor excess neutrons for burning long lived fission products  

Microsoft Academic Search

An evaluation is made on a large MOX fuel fast reactor's capability of burning long lived fission product Tc99, which dominates the long term radiotoxicity of the high level radioactive waste. The excess neutrons generated in the fast reactor core are utilized to transmute Tc-99 to stable isotopes due to neutron capture reaction.The fission product target assemblies which consist of

K Kawashima; K Kobayashi; K Kaneto

1995-01-01

104

An analysis of gamma-ray energy deposition in a heterogeneous liquid-metal fast breeder reactor  

Microsoft Academic Search

Gamma-dose analysis was performed on an absolute-value basis at the zero-power plutonium reactor (ZPPR)-13B\\/4 critical assembly, which was one of the benchmark radially heterogeneous 650-MW (electric) liquid-metal reactor cores, to validate the current data and methods applicable to power reactor design calculations. Discussions of particular aspects inherent to the critical measurements, such as heterogeneity in the ZPPR plate cells and

M. Kawashima; T. Yoshida; T. Yokoyama; T. Yamamoto

1989-01-01

105

Digital-Image Processing Improves Man-Machine Communication at a Nuclear Reactor.  

National Technical Information Service (NTIS)

The application of digital image processing to improve man-machine communication in a nuclear reactor control room is illustrated. At the Hanford N Reactor, operated by UNC Nuclear Industries for the United States Department of Energy, in Richland, Washin...

S. A. Cook T. P. Harrington H. Toffer

1982-01-01

106

Hydrogen Production Via a Commercially Ready Inorganic Membrane Reactor  

SciTech Connect

In the last report, we covered the experimental verification of the mathematical model we developed for WGS-MR, specifically in the aspect of CO conversion ratio, and the effect of the permeate sweep. Bench-top experimental study has been continuing in this period to verify the remaining aspects of the reactor performance, including hydrogen recovery ratio, hydrogen purity and CO contaminant level. Based upon the comparison of experimental vs simulated results in this period along with the results reported in the last period, we conclude that our mathematical model can predict reliably all aspects of the membrane reactor performance for WGS using typical coal gasifier off-gas as feed under the proposed operating condition. In addition to 250 C, the experimental study at 225 C was performed. As obtained at 250 C, the predicted values match well with the experimental results at this lower temperature. The pretreatment requirement in our proposed WGS-MR process can be streamlined to the particulate removal only. No excess water beyond the stoichiometric requirement for CO conversion is necessary; thus, power generation efficiency can be maximized. PROX will be employed as post-treatment for the elimination of trace CO. Since the CO contaminant level from our WGS-MR is projected to be 20-30 ppm, PROX can be implemented economically and reliably to deliver hydrogen with <10 ppm CO to meet the spec for PEM fuel cell. This would be a more cost effective solution than the production of on-spec hydrogen without the use of prost treatment. WGS reaction in the presence of sulfur can be accomplished with the use of the Co/MoS{sub 2} catalyst. This catalyst has been employed industrially as a sour gas shift catalyst. Our mathematical simulation on WGS-MR based upon the suggested pre- and post-treatment has demonstrated that a nearly complete CO conversion (i.e., 99+%) can be accomplished. Although conversion vs production cost may play an important role in an overall process optimization, no cost optimization has been taken into consideration presently. We estimate that {approx}90% of the hydrogen produced from the H{sub 2}+CO in the coal gasifier off-gas can be recovered via our proposed WGS-MR process. Its purity level ranges from 80 to 92% depending upon the H{sub 2}/CO{sub 2} selectivity of 10 to 25 respectively. If the purity of 95% is required, the hydrogen recovery ratio will drop to {approx}80% level for the membrane with H{sub 2}/CO{sub 2} = 25.

Paul K. T. Liu

2006-09-30

107

From discovery to production: Scale-out of continuous flow meso reactors  

PubMed Central

Summary A continuous flow parallel reactor system has been developed to provide a rapid and seamless transition from the discovery phase and production phase of chemical synthesis, particularly in low volume-high value pharmaceuticals production. Using a single fixed bed catalytic meso reactor, reactions can be screened on a small discovery scale over short time scales. The intensified process produces sufficient material for a full analysis. By replication of the single reactor in parallel, the same chemistry can be achieved on a larger scale, on a small footprint and without the mass and heat transport limitations of reactor scale-out in batch.

Parracho, Ana I R

2009-01-01

108

Recent BeO-reflector-controlled reactor experiments in ZPPR  

NASA Astrophysics Data System (ADS)

Integral reactor physics measurements were performed on a BeO-reflected fast reactor assembly in the Zero Power Plutonium Reactor Facility during January and February of 1985. The measurements emphasized power distributions and reflector control worths in two different critical states. The measurements have been analyzed using three-dimensional deterministic and Monte Carlo methods and the ENDF/B-V.2 nuclear data library. Together the measurements and analyses form a modern, reliable, benchmark data set for testing calculational methods that will be used in predicting some of the design parameters for future space reactors.

McFarlane, Harold F.; Brumbach, Stephen B.; Carpenter, Stuart G.; Collins, Peter J.; McKnight, Richard D.

109

Aspects of 238Pu production in the experimental fast reactor JOYO  

Microsoft Academic Search

Experimental determination of 238Pu in 237Np samples irradiated in the experimental fast reactor JOYO was done as part of the demonstration of 238Pu production from 237Np in fast reactors within the framework of the protected Pu production project, which aims at reinforcement of proliferation resistance of Pu by increasing the 238Pu isotopic ratio. 238Pu production amount in the irradiated 237Np

Masahiko Osaka; Shin-ichi Koyama; Masahiko Itoh; Masaki Saito

2005-01-01

110

A Novel Membrane Reactor for Direct Hydrogen Production from Coal  

SciTech Connect

Gas Technology Institute is developing a novel concept of membrane gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening, testing and identifying potential candidate membranes under high temperature, high pressure, and harsh environments of the coal gasification conditions. The best performing membranes will be selected for preliminary reactor design and cost estimates. To evaluate the performances of the candidate membranes under the gasification conditions, a high temperature/high pressure hydrogen permeation unit has been constructed in this project. The unit is designed to operate at temperatures up to 1100 C and pressures to 60 atm for evaluation of ceramic membranes such as mixed ionic conducting membrane. Several perovskite membranes based on the formulations of BCN (BaCe{sub 0.8}Nd{sub 0.2}O{sub 3-x}) and BCY (BaCe{sub 0.8}Y{sub 0.2}O{sub 3-x}) were prepared by GTI and successfully tested in the new permeation unit. During this reporting period, two different types of membranes, Eu-doped SrCeO{sub 3} (SCE) and SrCe{sub 0.95}Tm{sub 0.05}O{sub 3} (SCTm) provided by the University of Florida and the University of Cincinnati, respectively were tested in the high pressure permeation unit. The SCTm membrane, with a thickness of 1.7 mm, showed the highest hydrogen permeability among the perovskite membranes tested in this project so far. The hydrogen flux measured for the SCTm membrane was close to 0.8 cc/min/cm{sup 2} at a hydrogen feed pressure of about 4 bar at 950 C. SEM and EDX analysis for the tested SCTm membrane showed a separate Ce-rich phase deposited along the grain boundaries in the region towards the feed side of the membrane. No such phase separation was observed towards the permeate side. Partial reduction of the SCTm perovskite material by the high pressure hydrogen, especially in the feed side of the membrane, was postulated to be the possible reason for the phase separation. Further investigation of the stability issue of the perovskite membrane is needed.

Shain Doong, Estela Ong; Mike Atroshenko; Francis Lau; Mike Robers

2004-12-31

111

RELEASE OF FISSION PRODUCTS ON THE IN-PILE MELTING OR BURNING OF REACTOR FUELS  

Microsoft Academic Search

In-pile experiments are being conducted to study the release of fission products during simulated reactor accidents. Two types of experiments have been performed in the Oak Ridge Research Reactor to simulate reactor accidents in which fuel elements are destroyed by melting or burning. One type consisted of melting or vaporizing a miniature stainless-steel-clad UO2 fuel element in a helium atmosphere.

R. P. Shields; W. E. Browning; Jr. C. E. Miller; Jr. B. F. Roberts

112

Reactor production and processing of radioisotopes for therapeutic applications in nuclear medicine  

Microsoft Academic Search

Nuclear reactors continue to play an important role in providing radioisotopes for nuclear medicine. Many reactor-produced radioisotopes are ``neutron rich`` and decay by beta-emission and are thus of interest for therapeutic applications. This talk discusses the production and processing of a variety of reactor-produced radioisotopes of current interest, including those produced by the single neutron capture process, double neutron capture

F. F. Jr. Knapp; S. Mirzadeh; A. L. Beets

1995-01-01

113

High temperature growth of SiC and group III nitride structures in production reactors  

Microsoft Academic Search

We describe the use of a family of high temperature MOVPE reactors to grow SiC and III-V nitrides such as GaN. The load capacity ranges from single wafer machines to multiple wafer mass production reactors. All of these reactors have a two flow injection system, allowing separated inlet of the various reactants. To achieve maximum growth uniformity, the Gas Foil

D. Schmitz; R. Beccard; E. G. Woelk; G. Strauch; H. Juergensen

1998-01-01

114

Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes  

SciTech Connect

High Temperature Electrolysis (HTE), when coupled to an advanced nuclear reactor capable of operating at reactor outlet temperatures of 800 °C to 950 °C, has the potential to efficiently produce the large quantities of hydrogen needed to meet future energy and transportation needs. To evaluate the potential benefits of nuclear-driven hydrogen production, the UniSim process analysis software was used to evaluate different reactor concepts coupled to a reference HTE process design concept. The reference HTE concept included an Intermediate Heat Exchanger and intermediate helium loop to separate the reactor primary system from the HTE process loops and additional heat exchangers to transfer reactor heat from the intermediate loop to the HTE process loops. The two process loops consisted of the water/steam loop feeding the cathode side of a HTE electrolysis stack, and the steam or air sweep loop used to remove oxygen from the anode side. The UniSim model of the process loops included pumps to circulate the working fluids and heat exchangers to recover heat from the oxygen and hydrogen product streams to improve the overall hydrogen production efficiencies. The reference HTE process loop model was coupled to separate UniSim models developed for three different advanced reactor concepts (a high-temperature helium cooled reactor concept and two different supercritical CO2 reactor concepts). Sensitivity studies were then performed to evaluate the affect of reactor outlet temperature on the power cycle efficiency and overall hydrogen production efficiency for each of the reactor power cycles. The results of these sensitivity studies showed that overall power cycle and hydrogen production efficiencies increased with reactor outlet temperature, but the power cycle producing the highest efficiencies varied depending on the temperature range considered.

Edwin A. Harvego; Michael G. McKellar; James E. O'Brien; J. Stephen Herring

2007-04-01

115

Hydrogen production by biomass gasification in supercritical water with a fluidized bed reactor  

Microsoft Academic Search

Hydrogen production by biomass gasification in supercritical water (SCW) is a promising technology for utilizing high moisture content biomass, but reactor plugging is a critical problem for biomass gasification in the tubular reactor. A novel SCW fluidized bed system for biomass gasification was developed successfully in State Key Laboratory of Multiphase Flow in Power Engineering (SKLMF) to prevent the plugging

Y. J. Lu; H. Jin; L. J. Guo; X. M. Zhang; C. Q. Cao; X. Guo

2008-01-01

116

STAR - H2 : the secure transportable autonomous reactor for hydrogen production and desalinization.  

SciTech Connect

The Secure Transportable Autonomous Reactor for Hydrogen production is a modular fast reactor intended for the mid 21st century energy market wherein electricity and hydrogen are employed as complementary energy carriers and nuclear energy contributes to sustainable energy supply based on full transuranic recycle in a passively safe, environmentally friendly and proliferation-resistant manner suitable for widespread worldwide deployment.

Wade, D.C.; Doctor, R.; Peddicord, K.L.

2002-02-26

117

Phospholipase C-catalyzed sphingomyelin hydrolysis in a membrane reactor for ceramide production  

Microsoft Academic Search

A membrane reactor for the production of ceramide through sphingomyelin hydrolysis with phospholipase C from Clostridium perfringens was studied for the first time. Ceramide has raised a large interest as an active component in both pharmaceutical and cosmetic industry. The enzymatic hydrolysis of sphingomyelin has been proven to be a feasible method to produce ceramide. In the membrane reactor constructed,

Long Zhang; Shanshan Liang; Lars I. Hellgren; Gunnar Eigil Jonsson; Xuebing Xu

2008-01-01

118

Reactor production and processing of therapeutic radioisotopes for applications in nuclear medicine  

Microsoft Academic Search

In this paper the reactor production of a variety of therapeutic radionuclides of current clinical interest are discussed. Examples include radioisotopes produced by single neutron capture and those which are available from –\\/decay of reactor-produced parent radioisotopes. Two examples of generator parents produced by double neutron capture of targets are also discussed. One key example in this category is188W, produced

S. Mirzadeh; A. L. Beets

1996-01-01

119

Production Test IP-725 increased graphite temperature limit: F Reactor.  

National Technical Information Service (NTIS)

The fundamental objective of the graphite temperature limit is to prevent excessive oxidation of the graphite moderator blocks with carbon dioxide and water vapor in the reactor atmosphere. Laboratory tests have shown that 10 percent uniform oxidation of ...

A. Russell

1964-01-01

120

Search for Short Lived Isotopes in Volatile Reactor Fuel Products.  

National Technical Information Service (NTIS)

The volatile radioactive nuclides produced by thermal neutron fissioning of uranium oxide-polyethylene fuel of the AGN-201 Reactor were collected in an evacuated aluminum cylinder. The following constituent isotopes, identified by gamma ray spectrometry, ...

W. D. Fagan

1969-01-01

121

Identification of Volatile Reactor Fuel Decomposition Products by Spectral Analysis.  

National Technical Information Service (NTIS)

The volatile radioactive species produced by irradiation of AGN - 201 Reactor fuel elements were obtained by irradiation of the fuel in an evacuated inert container. Eleven constituent nuclides, including two radioactive daughters, were identified by gamm...

L. A. Lindsay

1968-01-01

122

Liquid phase methanol reactor staging process for the production of methanol  

DOEpatents

The present invention is a process for the production of methanol from a syngas feed containing carbon monoxide, carbon dioxide and hydrogen. Basically, the process is the combination of two liquid phase methanol reactors into a staging process, such that each reactor is operated to favor a particular reaction mechanism. In the first reactor, the operation is controlled to favor the hydrogenation of carbon monoxide, and in the second reactor, the operation is controlled so as to favor the hydrogenation of carbon dioxide. This staging process results in substantial increases in methanol yield.

Bonnell, Leo W. (Macungie, PA); Perka, Alan T. (Macungie, PA); Roberts, George W. (Emmaus, PA)

1988-01-01

123

Extreme thermophilic biohydrogen production from wheat straw hydrolysate using mixed culture fermentation: effect of reactor configuration.  

PubMed

Hydrogen production from hemicellulose-rich wheat straw hydrolysate was investigated in continuously-stirred tank reactor (CSTR), up-flow anaerobic sludge bed (UASB) reactor, and anaerobic filter (AF) reactor. The CSTR was operated at an hydraulic retention time (HRT) of 3 days, and the UASB and AF reactors were operated at 1 day HRT, using mixed extreme thermophiles at 70 °C. The highest hydrogen production yield of 212.0±6.6 mL-H?/g-sugars, corresponding to a hydrogen production rate of 821.4±25.5 mL-H?/dL was achieved with the UASB reactor. Lowering the HRT to 2.5 days caused cell mass washout in the CSTR, while the UASB and AF reactors gave fluctuating and reducing hydrogen production at a 0.5-day HRT. The original rate and yield were recovered when the HRT was increased back to 1 day. These results demonstrate that reactor configuration is an important factor for enhancing and stabilizing H? production. PMID:20554199

Kongjan, Prawit; Angelidaki, Irini

2010-10-01

124

Assemblies with both target and fuel pins in an isotope-production reactor  

DOEpatents

A method is described for producing tritium in a fast breeder reactor cooled with liquid metal. Lithium target material is placed in pins adjacent to fuel pins in order to increase the tritium production rate.

Cawley, W.E.; Omberg, R.P.

1982-08-19

125

Response of structures to energetic events for the Savannah River Site production reactors probabilistic risk assessment.  

National Technical Information Service (NTIS)

The response of structures to energetic events postulated to arise in a probabilistic risk assessment (PRA) of a Savannah River Site (SRS) production reactor is addressed. Energetic events that arise in PRAs can damage structures and therefore have a sign...

S. M. Santa Cruz D. C. Smith W. F. Yau

1992-01-01

126

Simulation of methane production in a laboratory-scale reactor containing hydrate-bearing porous medium  

SciTech Connect

Production of methane, induced by depressurization of hydrate sediment in a reactor, was investigated by numerical simulations using a computational fluid dynamics code TOUGH+/Hydrate. The methane production rates were computed at well-pressure drops of 4.2, 14.7, and 29.5 MPa and at a reactor temperature of 21 0C. The predicted behavior of methane production from the reactor is consistent with field-scale simulations and observations. The production rate increases with pressure drop at the well. Evolution patterns of gas and hydrate distributions are similar to those obtained in field-scale simulations. These preliminary results clearly indicate that numerical simulators can be applied to laboratory-scale reactors to anticipate scenarios observed in field experiments.

Gamwo, I.K.; Myshakin, E.M.; Zhang, Wu; Warzinski, R.P.

2008-01-01

127

Action Plan for updated Chapter 15 Accident Analysis in the SRS Production Reactor SAR  

SciTech Connect

This report describes the Action Plan for the upgrade of the Chapter 15 Accident Analysis in the SRS Production Reactor SAR required for K-Restart. This Action Plan will be updated periodically to reflect task accomplishments and issue resolutions.

Hightower, N.T. III; Burnett, T.W.

1989-11-15

128

Assessment of Natural Gas Splitting with a Concentrating Solar Reactor for Hydrogen Production  

Microsoft Academic Search

Hydrogen production via thermal decomposition of methane using a solar reactor is analyzed for two different applications: (1) for a fueling station and (2) for power production. For the fueling station, the selling price of hydrogen is controlled by the high cost of hydrogen storage and compression, combined with storage limitations of the system, which prevents maximum hydrogen production. Two

Pamela L. Spath; Wade A. Amos

2002-01-01

129

Fission product iodine and cesium release behavior under light water reactor accident conditions  

Microsoft Academic Search

The release behavior of the fission products iodine and cesium has been characterized in fission product release tests that have been conducted at Oak Ridge National Laboratory with highly irradiated, light water reactor fuel segments under conditions simulating severe accidents. The chemical forms of the fission products depended on the composition of the carrier gases used in the tests. In

J. L. Collins; M. F. Osborne; R. A. Lorenz; A. P. Malinauskas

1988-01-01

130

Tritium concentrations in the Columbia River at Richland  

SciTech Connect

The concentrations of tritium in the Columbia River, which are measurable using special analytical techniques, have been decreasing during recent years. Tritium levels are significantly greater at the Richland Pumphouse downstream of the Hanford Site than upstream at Priest Rapids Dam. Tritium is known to enter the river along the Hanford Site as direct effluent discharges, which have been virtually eliminated, and through the seepage of ground water contaminated as a result of past operations. The seepage of contaminated ground water has continued, expanding over time to encompass a larger portion of the Hanford shoreline nearer to the downstream Columbia River monitoring station. Cross-sectional sampling of the river was conducted to determine the distribution of tritium across the river and evaluate the relationship between average tritium concentrations in the river and those measured by the downstream river sampling system.

Dirkes, R.L.

1993-01-01

131

Routine environmental audit of the Hanford Site, Richland, Washington  

SciTech Connect

This report documents the results of the routine environmental audit of the Hanford Site (Hanford), Richland, Washington. During this audit, the activities conducted by the audit team included reviews of internal documents an reports from previous audits and assessments; interviews with US Department of Energy (DOE), State of Washington regulatory, and contractor personnel; and inspections and observations of selected facilities and operations. The onsite portion of the audit was conducted May 2--13, 1994, by the DOE Office of Environmental Audit (EH-24), located within the Office of Environment, Safety and Health (EH). The audit evaluated the status of programs to ensure compliance with Federal, State, and local environmental laws and regulations; compliance with DOE orders, guidance, and directives; and conformance with accepted industry practices and standards of performance. The audit also evaluated the status and adequacy of the management systems developed to address environmental requirements.

Not Available

1994-05-01

132

Methane production in an UASB reactor operated under periodic mesophilic-thermophilic conditions.  

PubMed

Methane production was studied in a laboratory-scale 10 L anaerobic upflow sludge bed (UASB) reactor with periodic variations of the reactor temperature. On a daily basis the temperature was varied between 35 and 45 degrees C or 35 and 55 degrees C with a heating period of 6 h. Each temperature increase was accompanied by an increase in methane production and a decrease in the concentration of soluble organic matter in the effluent. In comparison to a reactor operated at 35 degrees C, a net increase in methane production of up to 22% was observed. Batch activity tests demonstrated a tolerance of mesophilic methanogenic populations to short-term, 2-6 h, temperature increases, although activity of acetoclastic methanogens decreased after 6 h exposure to a temperature of 55 degrees C. 16S sequencing of DGGE bands revealed proliferation of temperature-tolerant Methanospirillum hungatii sp. in the reactor. PMID:18383125

Bourque, J-S; Guiot, S R; Tartakovsky, B

2008-08-15

133

Biological production of ethanol from coal. Task 4 report, Continuous reactor studies  

SciTech Connect

The production of ethanol from synthesis gas by the anaerobic bacterium C. ljungdahlii has been demonstrated in continuous stirred tank reactors (CSTRs), CSTRs with cell recycle and trickle bed reactors. Various liquid media were utilized in these studies including basal medium, basal media with 1/2 B-vitamins and no yeast extract and a medium specifically designed for the growth of C. ljungdahlii in the CSTR. Ethanol production was successful in each of the three reactor types, although trickle bed operation with C. ljungdahlii was not as good as with the stirred tank reactors. Operation in the CSTR with cell recycle was particularly promising, producing 47 g/L ethanol with only minor concentrations of the by-product acetate.

Not Available

1992-10-01

134

Experience in Monitoring the BWR (Boiling Water Reactor) Fuel Behaviour and Fission Product Releases During off Normal Conditions.  

National Technical Information Service (NTIS)

Tarapur Atomic Power Station has accumulated over 33 reactor years of operating experience in monitoring Boiling Water Reactor fuel behavior. The sudden and sharp increases in the fission product releases were experienced in the earlier years due to gross...

N. B. Joshi V. S. inivasan K. Nanjundeswaran

1986-01-01

135

Three-reactors chemical looping process for hydrogen production  

Microsoft Academic Search

This paper analyzes a novel process for producing hydrogen from natural gas, based on chemical looping (CL) techniques, allowing for intrinsic capture of carbon dioxide. The core of the process consists of a three-reactors CL system, where iron oxide particles are circulated to: (i) oxidize natural gas (thus providing, after cooling and water condensation, a CO2 stream ready for sequestration),

Paolo Chiesa; Giovanni Lozza; Alberto Malandrino; Matteo Romano; Vincenzo Piccolo

2008-01-01

136

Study on Conceptual Design of Tritium Production Reactor Based on ST  

NASA Astrophysics Data System (ADS)

A preliminary conceptual design of an advanced tritium production fusion reactor based on Spherical Torus (ST) as intermediate application of fusion energy was presented in this paper. Different from traditional Tokamak tritium production reactor design, advanced plasma physics performance and compact structural characteristics of ST configuration were used to minimize tritium leakage and to maximize tritium breeding ratio with arrangement of tritium production blankets as possible as it can within vacuum vessel in order to produce 1kg excess tritium except self-sufficient plasma core, corresponding plant availability 40%. Based on 2D Neutronic calculation, a preliminary conceptual design of ST-TPR was presented. The tritium breeding ratio, resulted from 2D neutronics calculation, high up to 1.68 has not yet been available in previous tritium production reactor design, which shows that tritium production based on ST is more advanced than other ways.

He, Kaihui; Huang, Jinhua

2003-06-01

137

Supplying the nuclear arsenal: Production reactor technology, management, and policy, 1942--1992  

SciTech Connect

This book focuses on the lineage of America`s production reactors, those three at Hanford and their descendants, the reactors behind America`s nuclear weapons. The work will take only occasional sideways glances at the collateral lines of descent, the reactor cousins designed for experimental purposes, ship propulsion, and electric power generation. Over the decades from 1942 through 1992, fourteen American production reactors made enough plutonium to fuel a formidable arsenal of more than twenty thousand weapons. In the last years of that period, planners, nuclear engineers, and managers struggled over designs for the next generation of production reactors. The story of fourteen individual machines and of the planning effort to replace them might appear relatively narrow. Yet these machines lay at the heart of the nation`s nuclear weapons complex. The story of these machines is the story of arming the winning weapon, supplying the nuclear arms race. This book is intended to capture the history of the first fourteen production reactors, and associated design work, in the face of the end of the Cold War.

Carlisle, R.P.; Zenzen, J.M.

1994-01-01

138

REACTOR  

DOEpatents

A breeder reactor is described, including a mass of fissionable material that is less than critical with respect to unmoderated neutrons and greater than critical with respect to neutrons of average energies substantially greater than thermal, a coolant selected from sodium or sodium--potassium alloys, a control liquid selected from lead or lead--bismuth alloys, and means for varying the quantity of control liquid in the reactor. (AEC)

Szilard, L.

1963-09-10

139

Impact of varying lignocellulosic sugars on continuous solvent production in an immobilized column reactor.  

PubMed

The effect of varying glucose, mannose and xylose concentrations on continuous solvent production at various dilution rates was studied by multiple linear regression (MLR) modeling using an immobilized column reactor. The factors affecting the solvent production were dilution rate and concentrations of glucose and mannose. MLR-models also showed a preference of glucose as well as its inhibitory effect on xylose consumption. The fermentation process was studied at bigger scale with a volume factor of 17 with an added recirculation loop in the system. The up-scaled reactor produced 12.5g/l of acetone-butanol-ethanol (ABE) solvents at a dilution rate of 0.23h(-1), as compared to 13.4g/l with a smaller column reactor. The xylose utilization was significantly higher in the modified reactor (73%) as compared to the small scale (43%). PMID:24001559

Viikilä, Matti; Wallenius, Janne; Ojamo, Heikki; Granström, Tom; Survase, Shrikant A

2013-08-15

140

Analysis of fission-product effects in a Fast Mixed-Spectrum Reactor concept  

SciTech Connect

The Fast Mixed-Spectrum Reactor (FMSR) concept has been proposed by BNL as a means of alleviating certain nonproliferation concerns relating to civilian nuclear power. This breeder reactor concept has been tailored to operate on natural uranium feed (after initial startup), thus eliminating the need for fuel reprocessing. The fissile material required for criticality is produced, in situ, from the fertile feed material. This process requires that large burnup and fluence levels be achievable, which, in turn, necessarily implies that large fission-product inventories will exist in the reactor. It was the purpose of this study to investigate the effects of large fission-product inventories and to analyze the effect of burnup on fission-product nuclide distributions and effective cross sections. In addition, BNL requested that a representative 50-group fission-product library be generated for use in FMSR design calculations.

White, J.R.; Burns, T.J.

1980-02-01

141

Reactor production and processing of radioisotopes for therapeutic applications in nuclear medicine  

SciTech Connect

Nuclear reactors continue to play an important role in providing radioisotopes for nuclear medicine. Many reactor-produced radioisotopes are ``neutron rich`` and decay by beta-emission and are thus of interest for therapeutic applications. This talk discusses the production and processing of a variety of reactor-produced radioisotopes of current interest, including those produced by the single neutron capture process, double neutron capture and those available from beta-decay of reactorproduced radioisotopes. Generators prepared from reactorproduced radioisotopes are of particular interest since repeated elution inexpensively provides many patient doses. The development of the alumina-based W-188/Re-188 generator system is discussed in detail.

Knapp, F.F. Jr.; Mirzadeh, S.; Beets, A.L.

1995-02-01

142

Production of Sn-117m in the BR2 high-flux reactor.  

PubMed

The BR2 reactor is a 100MW(th) high-flux 'materials testing reactor', which produces a wide range of radioisotopes for various applications in nuclear medicine and industry. Tin-117m ((117m)Sn), a promising radionuclide for therapeutic applications, and its production have been validated in the BR2 reactor. In contrast to therapeutic beta emitters, (117m)Sn decays via isomeric transition with the emission of monoenergetic conversion electrons which are effective for metastatic bone pain palliation and radiosynovectomy with lesser damage to the bone marrow and the healthy tissues. Furthermore, the emitted gamma photons are ideal for imaging and dosimetry. PMID:19303313

Ponsard, B; Srivastava, S C; Mausner, L F; Russ Knapp, F F; Garland, M A; Mirzadeh, S

2009-02-20

143

Production of Sn-117m in the BR2 and HFIR Research Reactors  

SciTech Connect

The BR2 reactor is a 100 MW{sub th} high-flux 'materials testing reactor', which produces a wide range of radioisotopes for various applications in nuclear medicine and industry. Tin-117m ({sup 117m}Sn), a promising radionuclide for therapeutic applications, and its production have been validated in the BR2 reactor. In contrast to therapeutic beta emitters, {sup 117m}Sn decays via isomeric transition with the emission of monoenergetic conversion electrons which are effective for metastatic bone pain palliation and radiosynovectomy with lesser damage to the bone marrow and the healthy tissues. Furthermore, the emitted gamma photons are ideal for imaging and dosimetry.

Ponsard, B.; Srivastava, S.; Garland, M.; Knapp, R.; Mirzadeh, S.; Mausner, L.F.

2009-07-01

144

On a simplified system for steam production in nuclear power plants with pressurized water reactors  

Microsoft Academic Search

The paper develops the idea of a new system of steam production (Simplified System for Steam Production, SSSP) in nuclear power plants (NPPs) with PWR reactors, which is simplified as compared to the system used in the classical NPP of this type where steam is produced by steam generators (SGs). With the SSSP, expanders are used instead of SGs. The

Mircea Cârdu; Marian Dumitru

1999-01-01

145

Modeling of oligodextran production in an ultrafiltration stirred-cell membrane reactor  

Microsoft Academic Search

The aim of this study was to investigate the types of oligodextrans that could be generated via controlled enzymatic depolymerization of dextran using an endodextranase. An ultrafiltration stirred-cell membrane reactor was employed to provide the means of controlling product molecular size and characteristics. The process was operated in batch mode and the products were recovered as permeates. The effect of

K. C. Mountzouris; S. G. Gilmour; A. S. Grandison; R. A. Rastall

1999-01-01

146

Lactic acid production by immobilized Lactobacillus casei in recycle batch reactor: a step towards optimization  

Microsoft Academic Search

Different nutritional and process parameters influencing lactic acid production by Lactobacillus casei, adsorbed to Poraver beads in a recycle batch reactor system, were studied in an attempt to set up a system having a long operational lifetime and permitting use of high substrate concentrations for maximal conversion to the product. The presence of lactose, even as a minor fraction of

Appadurai Senthuran; Vasanthe Senthuran; Rajni Hatti-Kaul; Bo Mattiasson

1999-01-01

147

Corrosion of Fast-Reactor Claddings by Physical and Chemical Interaction with Fuel and Fission Products  

Microsoft Academic Search

Fuel-cladding chemical interaction in fast breeder reactor (FBR) fuel pins can cause both matrix and intergranular corrosion of the inner surface of the cladding. Matrix corrosion is uniform nonselective interaction with fuel and fission products, causing the cladding to thin. Intergranular corrosion occurs on grain boundaries, weakening both them and the grains. Interaction with fission products may be the cause

V. A. TZYKANOV; V. N. GOLOVANOV; V. K. SHAMARDIN; F. N. KRYUKOV; A. V. POVSTYANKO

148

A study of fission product transport from failed fuel during N reactor postulated accidents  

Microsoft Academic Search

This report presents a study of fission product transport behavior in N Reactor during a severe accident. More detail about fission product behavior than has previously been available is provided and key parameters that control this behavior are identified. The current report is an extension to a previous interum study that has added an aerosol formation model, replaced an older

Hagrman

1989-01-01

149

Biomass pyrolysis in a circulating fluid bed reactor for the production of fuels and chemicals  

Microsoft Academic Search

An approach for biomass flash pyrolysis in a circulating fluid bed (CFB) reactor with continuous solids regeneration is described in this study. The unit is capable of performing conventional and catalytic biomass pyrolysis with the proper solid selection. The production of improved quality liquid products in a direct step through catalytic pyrolysis is investigated in this work. Both conventional and

A. A Lappas; M. C Samolada; D. K Iatridis; S. S Voutetakis; I. A Vasalos

2002-01-01

150

Effect of reactor configuration on biogas production from wheat straw hydrolysate  

Microsoft Academic Search

The potential of wheat straw hydrolysate for biogas production was investigated in continuous stirred tank reactor (CSTR) and up-flow anaerobic sludge bed (UASB) reactors. The hydrolysate originated as a side stream from a pilot plant pretreating wheat straw hydrothermally (195°C for 10–12min) for producing 2nd generation bioethanol [Kaparaju, P., Serrano, M., Thomsen, A.B., Kongjan, P., Angelidaki, I., 2009. Bioethanol, biohydrogen

Prasad Kaparaju; María Serrano; Irini Angelidaki

2009-01-01

151

Butanol production by Clostridium acetobutylicum in a continuous packed bed reactor  

Microsoft Academic Search

In this study, we report on a butanol production process by immobilized Clostridium acetobutylicum in a continuous packed bed reactor (PBR) using Tygon® rings as a carrier. The medium was a solution of lactose (15–30 g\\/L) and yeast extract (3 g\\/L) to emulate the cheese whey,\\u000a an abundant lactose-rich wastewater. The reactor was operated under controlled conditions with respect to the pH

Fabio Napoli; Giuseppe Olivieri; Maria Elena Russo; Antonio Marzocchella; Piero Salatino

2010-01-01

152

Correlations for fission product release from N Reactor fuel under high-temperature accident conditions  

SciTech Connect

Empirical correlations were derived for fission product release from metallic uranium alloy 601 N Reactor fuel during postulated accident conditions in which the fuel nears, reaches, or exceeds the melting temperature. The correlations were based on a sparse data base from fuel melted in an inert or steam atmosphere. The empirical correlations are presented for use in subsequent deterministic analyses of N Reactor behavior during hypothetical severe accidents beyond the design basis. 20 refs., 4 figs., 4 tabs.

Birney, K.R.; Bechtold, D.B.; McCall, T.B.

1988-03-01

153

Production of whey protein hydrolysates with reduced allergenicity in a stable membrane reactor  

Microsoft Academic Search

In this paper, a process for the stable production of low allergenicity hydrolysates is presented. Whey protein was hydrolysed at 50°C and pH 8.5 using a bacterial protease in a continuous stirred tank membrane reactor including a polyethersulfone plate and frame ultrafiltration module with a molecular weight cut-off of 3kDa. The reactor was maintained in operation for 16h. Conversion reached

Antonio Guadix; Fernando Camacho; Emilia M. Guadix

2006-01-01

154

Continuous biohydrogen production from diluted molasses in an anaerobic contact reactor  

Microsoft Academic Search

An anaerobic contact reactor (ACR) system comprising a continuous flow stirred tank reactor (CSTR) with settler to decouple\\u000a the hydraulic retention time (HRT) from solids retention time (SRT) was developed for fermentative hydrogen production from\\u000a diluted molasses by mixed microbial cultures. The ACR was operated at various volumetric loading rates (VLRs) of 20–44 kgCOD·m?3·d?1 with constant HRT of 6 h

Sheng Chang; Jianzheng Li; Feng Liu

2011-01-01

155

Technical and economic evaluation of different reactors for methanotrophic cultures for propylene oxide production.  

PubMed

A two-stage process for the manufacture of propylene oxide is described. The preliminary economics based on use of methanol as a regeneration factor has resulted in a production cost of $12.10/lb of propylene oxide based on propylene oxide production rate of 40 mg/g-cell/h in conventional reactor. Increasing the propylene oxide production from 40 to 500 mg/g-cell/h resulted in a cost reduction from $12.10 to 5.8/lb of propylene oxide. The granular-activated, carbon-fluidized bed reactor (GAC-FBR) absorbs the propylene oxide and when saturated is eluted with ethyl acetate, and the bed is regenerated by steam to drive off the residual solvents. The estimated manufacturing costs are approx 59% lower (from $12.10/lb in conventional reactors to $5.00/lb for GAC-FBRs) for products that are highly inhibitory such as epoxides. In the GAC-FBR reactor, enhancing the propylene oxide production rate from 120 to 1500 mg/g-cell/h has resulted in the cost reduction to $2.00/lb. Enhancing the production capacity from 1 million lb to 10 million lb/yr has further reduced the cost of production to $1.00/lb. PMID:18576029

Soni, B K; Kelley, R L; Srivastava, V J

1998-01-01

156

ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS, AND THE FEDERAL GOVERNMENT - 11052  

Microsoft Academic Search

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River (SRS) near Aiken, South Carolina. Nuclear weapons material production began in the early 1950s, utilizing five production reactors. In the early 1990s all SRS production reactor operations were terminated. The first reactor closure end state declaration was recently institutionalized in

C. Bergren; M. Flora; H. Belencan

2010-01-01

157

ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS AND THE FEDERAL GOVERNMENT  

Microsoft Academic Search

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River (SRS) near Aiken, South Carolina. Nuclear weapons material production began in the early 1950s, utilizing five production reactors. In the early 1990s all SRS production reactor operations were terminated. The first reactor closure end state declaration was recently institutionalized in

Bergren

2009-01-01

158

MHTGR: New production reactor summary of experience base  

SciTech Connect

Worldwide interest in the Modular High-Temperature Gas-Cooled Reactor (MHTGR) stems from the capability of the system to retain the advanced fuel and thermal performance while providing unparalleled levels of safety. The small power level of the MHTGR and its passive systems give it a margin of safety not attained by other concepts being developed for power generation. This report covers the experience base for the key nuclear system, components, and processes related to the MHTGR-NPR. 9 refs., 39 figs., 9 tabs.

Not Available

1988-03-01

159

REACTOR  

DOEpatents

A pressurized water reactor in which automatic control is achieved by varying the average density of the liquid moderator-cooiant is patented. Density is controlled by the temperature and power level of the reactor ftself. This control can be effected by the use of either plate, pellet, or tubular fuel elements. The fuel elements are disposed between upper and lower coolant plenum chambers and are designed to permit unrestricted coolant flow. The control chamber has an inlet opening communicating with the lower coolant plenum chamber and a restricted vapor vent communicating with the upper coolant plenum chamber. Thus, a variation in temperature of the fuel elements will cause a variation in the average moderator density in the chamber which directly affects the power level of the reactor.

Roman, W.G.

1961-06-27

160

Plasma-arc reactor for production possibility of powdered nano-size materials  

NASA Astrophysics Data System (ADS)

Nano-size materials of various chemical compositions find increasing application in life nowadays due to some of their unique properties. Plasma technologies are widely used in the production of a range of powdered nano-size materials (metals, alloys, oxides, nitrides, carbides, borides, carbonitrides, etc.), that have relatively high melting temperatures. Until recently, the so-called RF-plasma generated in induction plasma torches was most frequently applied [1-3]. The subject of this paper is the developments of a new type of plasma-arc reactor, operated with transferred arc system for production of disperse nano-size materials. The new characteristics of the PLASMALAB reactor are the method of feeding the charge, plasma arc control and anode design. The disperse charge is fed by a charge feeding system operating on gravity principle through a hollow cathode of an arc plasma torch situated along the axis of a water-cooled wall vertical tubular reactor. The powdered material is brought into the zone of a plasma space generated by the DC rotating transferred plasma arc. The arc is subjected to Auto-Electro-Magnetic Rotation (AEMR) by an inductor serially connected to the anode circuit. The anode is in the form of a water-cooled copper ring. It is mounted concentrically within the cylindrical reactor, with its lower part electrically insulated from it. The electric parameters of the arc in the reactor and the quantity of processed charge are maintained at a level permitting generation of a volumetric plasma discharge. This mode enables one to attain high mean mass temperature while the processed disperse material flows along the reactor axis through the plasma zone where the main physico-chemical processes take place. The product obtained leaves the reactor through the annular anode, from where it enters a cooling chamber for fixing the produced nano-structure. Experiments for AlN synthesis from aluminium power and nitrogen were carried out using the plasma reactor described here above.

Hadzhiyski, V.; Mihovsky, M.; Gavrilova, R.

2011-01-01

161

Group Constants Generation of the Pseudo Fission Products for Fast Reactor Burnup Calculations  

SciTech Connect

The pseudo fission products for the burnup calculations of the liquid metal fast reactor were generated. The cross-section data and fission product yield data of ENDF/B-VI were used for the pseudo fission product data of U-235, U-238, Pu-239, Pu-240, Pu-241, and Pu-242. The pseudo fission product data can be used with the KAFAX-F22 or -E66, which are the MATXS-format libraries for analyses of the liquid metal fast reactor at KAERI and were distributed through the OECD/NEA. The 80-group MATXS-format libraries of the 172 fission products were generated and the burnup chains for generation of the pseudo fission products were prepared.

Gil, Choong-Sup; Kim, Do Heon; Chang, Jonghwa [Korea Atomic Energy Research Institute, 150 Dukjin-dong, Yusung-gu, Taejon (Korea, Republic of)

2005-05-24

162

Group Constants Generation of the Pseudo Fission Products for Fast Reactor Burnup Calculations  

NASA Astrophysics Data System (ADS)

The pseudo fission products for the burnup calculations of the liquid metal fast reactor were generated. The cross-section data and fission product yield data of ENDF/B-VI were used for the pseudo fission product data of U-235, U-238, Pu-239, Pu-240, Pu-241, and Pu-242. The pseudo fission product data can be used with the KAFAX-F22 or -E66, which are the MATXS-format libraries for analyses of the liquid metal fast reactor at KAERI and were distributed through the OECD/NEA. The 80-group MATXS-format libraries of the 172 fission products were generated and the burnup chains for generation of the pseudo fission products were prepared.

Gil, Choong-Sup; Kim, Do Heon; Chang, Jonghwa

2005-05-01

163

Air quality impact analysis in support of the new production reactor environmental impact statement  

SciTech Connect

The Pacific Northwest Laboratory (PNL) conducted this air quality impact analysis for the US Department of Energy (DOE). The purpose of this work was to provide Argonne National Laboratory (ANL) with the required estimates of ground-level concentrations of five criteria air pollutants at the Hanford Site boundary from each of the stationary sources associated with the new production reactor (NPR) and its supporting facilities. The DOE proposes to provide new production capacity for the primary production of tritium and secondary production of plutonium to support the US nuclear weapons program. Three alternative reactor technologies are being considered by DOE: the light-water reactor, the low-temperature, heavy-water reactor, and the modular high-temperature, gas-cooled reactor. In this study, PNL provided estimates of the impacts of the proposed action on the ground-level concentration of the criteria air pollutants for each of the alternative technologies. The criteria pollutants were sulfur dioxide, nitrogen dioxide, carbon monoxide, total suspended particulates, and particulates with a diameter of less than 10 microns. Ground-level concentrations were estimated for the peak construction phase activities expected to occur in 1997 and for the operational phase activities beginning in the year 2000. Ground-level concentrations of the primary air pollutants were estimated to be well below any of the applicable national or state ambient air quality standards. 12 refs., 19 tabs.

Hadley, D L

1991-04-01

164

Production of a Biopolymer at Reactor Scale: A Laboratory Experience  

ERIC Educational Resources Information Center

|Undergraduate students of biotechnology became familiar with several aspects of bioreactor operation via the production of xanthan gum, an industrially relevant biopolymer, by "Xanthomonas campestris" bacteria. The xanthan gum was extracted from the fermentation broth and the yield coefficient and productivity were calculated. (Contains 2…

Genc, Rukan; Rodriguez-Couto, Susana

2011-01-01

165

Columbia River monitoring: Distribution of tritium in Columbia River water at the Richland Pumphouse  

SciTech Connect

The Surface Environmental Surveillance Project (SESP) is conducted by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). This report presents the results of a special study conducted as part of the SESP to supplement the routine Columbia River monitoring program and provide information relative to the dispersion and distribution of Hanford origin contaminants entering the river through the seepage of ground water along the Hanford Site. Sampling was conducted along cross sections to determine the distribution of tritium within the Columbia River at Richland, Washington. The investigation was also designed to evaluate the relationship between the average tritium concentrations in the river water at this location and in water collected from the routine SESP river monitoring system located at the city of Richland drinking water intake (Richland Pumphouse). This study was conducted during the summers of 1987 and 1988. Water samples were collected along cross sections located at or near the Richland Pumphouse monitoring station.

Dirkes, R.L.

1993-02-01

166

Improvement in the bioreactor specific productivity by coupling continuous reactor with repeated fed-batch reactor for acetone-butanol-ethanol production.  

PubMed

In comparison to the different fermentation modes for the production of acetone, butanol and ethanol (ABE) researched to date, the continuous fermentation is the most economically favored. Continuous fermentation with two or more reactor cascade is reported to be the most efficient as it results in a more stable solvent production process. In this work, it is shown that a continuous (first-stage) reactor coupled to a repeated fed-batch (second stage) is superior to batch and fed-batch fermentations, including two-stage continuous fermentation. This is due to the efficient catalyst use, reported through the specific product rate and rapid glucose consumption rate. High solvents are produced at 19.4 g(ABE) l?¹, with volumetric productivities of 0.92 g(butanol) l?¹ h?¹ and 1.47 g(ABE) l ?¹ h?¹. The bioreactor specific productivities of 0.62 and 0.39 g g?¹(cdw) h?¹ obtained show a high catalyst activity. This new process mode has not been reported before in the development of ABE fermentation and it shows great potential and superiority to the existing fermentation methods. PMID:22542935

Setlhaku, Mpho; Brunberg, Sina; Villa, Eva Del Amor; Wichmann, Rolf

2012-04-19

167

REACTOR  

DOEpatents

The system conteraplates ohmically heating a gas to high temperatures such as are useful in thermonuclear reactors of the stellarator class. To this end the gas is ionized and an electric current is applied to the ionized gas ohmically to heat the gas while the ionized gas is confined to a central portion of a reaction chamber. Additionally, means are provided for pumping impurities from the gas and for further heating the gas. (AEC)

Spitzer, L. Jr.

1962-01-01

168

Optimization of outdoor cultivation in flat panel airlift reactors for lipid production by Chlorella vulgaris.  

PubMed

Microalgae are discussed as a potential renewable feedstock for biofuel production. The production of highly concentrated algae biomass with a high fatty acid content, accompanied by high productivity with the use of natural sunlight is therefore of great interest. In the current study an outdoor pilot plant with five 30?L Flat Panel Airlift reactors (FPA) installed southwards were operated in 2011 in Stuttgart, Germany. The patented FPA reactor works on the basis of an airlift loop reactor and offers efficient intermixing for homogeneous light distribution. A lipid production process with the microalgae Chlorella vulgaris (SAG 211-12), under nitrogen and phosphorous deprivation, was established and evaluated in regard to the fatty acid content, fatty acid productivity and light yield. In the first set of experiments limitations caused by restricted CO2 availability were excluded by enriching the media with NaOH. The higher alkalinity allows a higher CO2 content of supplied air and leads to doubling of fatty acid productivity. The second set of experiments focused on how the ratio of light intensity to biomass concentration in the reactor impacts fatty acid content, productivity and light yield. The specific light availability was specified as mol photons on the reactor surface per gram biomass in the reactor. This is the first publication based on experimental data showing the quantitative correlation between specific light availability, fatty acid content and biomass light yield for a lipid production process under nutrient deprivation and outdoor conditions. High specific light availability leads to high fatty acid contents. Lower specific light availability increases fatty acid productivity and biomass light yield. An average fatty acid productivity of 0.39?g?L(-1) ?day(-1) for a 12 days batch process with a final fatty acid content of 44.6% [w/w] was achieved. Light yield of 0.4?g?mol?photons(-1) was obtained for the first 6 days of cultivation. Biotechnol. Bioeng. 2013;110: 2882-2893. © 2013 Wiley Periodicals, Inc. PMID:23616347

Münkel, Ronja; Schmid-Staiger, Ulrike; Werner, Achim; Hirth, Thomas

2013-05-16

169

Hydrogen production from propane in Rh-impregnated metallic microchannel reactors and alumina foams  

Microsoft Academic Search

Rh-impregnated alumina foams and metallic microchannel reactors have been studied for production of hydrogen-rich syngas through short contact time catalytic partial oxidation (POX) and oxidative steam reforming (OSR) of propane. Effects of temperature and residence time have been compared for the two catalytic systems. Temperature profiles obtained along the central axis were valuable in understanding the different behaviour of the

Ingrid Aartun; Bozena Silberova; Hilde Venvik; Peter Pfeifer; Oliver Görke; Klaus Schubert; Anders Holmen

2005-01-01

170

Solar energy concentrating reactors for hydrogen production by photoelectrochemical water splitting  

Microsoft Academic Search

The use of solar energy to produce hydrogen by electrolysis is one potential renewable hydrogen source to fuel a future hydrogen economy. A cost-effective, renewable source of hydrogen is needed to reduce the emissions of carbon dioxide that occur with hydrogen-production methods utilizing fossil fuels. This report describes the design, construction, and testing of simple and inexpensive photoelectrochemical (PEC) reactors

Nelson A. Kelly; Thomas L. Gibson

2008-01-01

171

Semi-continuous hydrogen production from catalytic methane decomposition using a fluidized-bed reactor  

Microsoft Academic Search

Non-oxidative, catalytic decomposition of hydrocarbons is an alternative, one-step process to produce pure hydrogen with no production of carbon oxides or higher hydrocarbons. Carbon produced from the decomposition reaction, in the form of potentially valuable carbon nanotubes, remains anchored to the active catalyst sites in a fixed bed. To facilitate periodical removal of this carbon from the reactor and to

Naresh Shah; Shankang Ma; Yuguo Wang; Gerald P. Huffman

2007-01-01

172

Hydrogen production by catalytic cracking of methane over nickel gauze under periodic reactor operation  

Microsoft Academic Search

The catalytic cracking of methane over nickel gauze is proposed as an attractive alternative for the production of CO-free hydrogen. The catalyst deactivates due to intensive coke deposition. Therefore, the reactor was operated periodically with the reaction followed by the catalyst regeneration by burning of coke in oxidative atmosphere. The optimal reaction performance was found to consist of reaction periods

B. Monnerat; L. Kiwi-Minsker; A. Renken

2001-01-01

173

Characteristics and biogas production potential of municipal solid wastes pretreated with a rotary drum reactor  

Microsoft Academic Search

This study was conducted to determine the characteristics and biogas production potential of organic materials separated from municipal solid wastes using a rotary drum reactor (RDR) process. Four different types of wastes were first pretreated with a commercial RDR system at different retention times (1, 2 and 3 d) and the organic fractions were tested with batch anaerobic digesters with

Baoning Zhu; Petros Gikas; Ruihong Zhang; James Lord; Bryan Jenkins; Xiujin Li

2009-01-01

174

Vapor transport of fission products in postulated severe light water reactor accidents  

Microsoft Academic Search

A methodology based on chemical thermodynamics has been developed to treat the transport of volatile fission products (FPs) through the core and the primary system. The FPs considered are cesium, iodine, tellurium, strontium, and ruthenium, which may pose the major biohazard in postulated severe accidents in light water reactors. The vapor transport of FPs depends on the volatilities of the

D. Cubicciotti; B. R. Sehgal

1984-01-01

175

Modeling requirements for full-scope reactor simulators of fission-product transport during severe accidents  

Microsoft Academic Search

This paper describes in the needs and requirements to properly and efficiently model fission product transport on full scope reactor simulators. Current LWR simulators can be easily adapted to model severe accident phenomena and the transport of radionuclides. Once adapted these simulators can be used as a training tool during operator training exercises for training on severe accident guidelines, for

P. G. Ellison; P. R. Monson; H. A. Mitchell

1990-01-01

176

Co-Product Extraction Studies on n-Reactor Pt-57 Target Materials.  

National Technical Information Service (NTIS)

Single pellets (of approximately 70 g each) of irradiated lithium aluminate target from N-Reactor test PT-57 were used in a series of experiments to determine the extent to which the product tritium can be recovered by (a) vacuum outgassing of the target ...

W. H. Yunker W. O. Greenhalgh J. R. Lundquist T. S. Soine K. M. Harmon

1966-01-01

177

A NOVEL CONTINUOUS-FLOW REACTOR USING REACTIVE DISTILLATION FOR BIODIESEL PRODUCTION  

Microsoft Academic Search

The production of biodiesel through batch and existing continuous-flow processes requires the use of a much higher excess alcohol, typically 100%, than the stoichiometric molar requirement in order to drive the transesterification reaction to completion. This excess alcohol must be recovered in a separate process, which involves additional capital and operating costs. In this study, a novel reactor system using

B. B. He; A. P. Singh; J. C. Thompson

178

Fuel processor based on syngas production via short contact time catalytic partial oxidation reactors  

Microsoft Academic Search

Short contact time catalytic partial oxidation (SCT-CPO) of natural gas is a promising technology for syngas production, representing an appealing alternative to existing processes. The high conversion and selectivity observed since the earlier works in this field can make this process attractive. Moreover, the SCT-CPO reactors can be autothermally operated and the possibility to use air as oxidant appears a

Stefania Specchia; Giovanna Negro; Guido Saracco; Vito Specchia

2007-01-01

179

Vertical high-speed rotating disk reactors for production scale MOVPE of compound semiconductors  

Microsoft Academic Search

Compound semiconductors are at the heart of todays advanced digital and optoelectronic devices. As device production levels increase, so too does the need for high throughput deposition systems. The vertical rotating disk reactor (RDR) has been scaled to dimensions allowing metal organic chemical vapor deposition (MOCVD) on multiple substrates located on a 300 mm diameter platter. This symmetric large area

R. C. Walker; A. G. Thompson; Gary S. Tompa; Peter A. Zawadzki; Alexander Gurary

1994-01-01

180

Hydrogen Production by High Temperature Electrolysis with Nuclear Reactor  

SciTech Connect

In this paper, we report our design of high temperature electrolysis plant system and the analysis results. The system efficiency increases with the increase of the steam utilization in the solid oxide electrolysis cell (SOEC) or the decrease of the hydrogen recycle (hydrogen recycle flow to product hydrogen flow) ratio,. The system efficiency is nearly independent of the SOEC operating temperature and pressure, and the air to product O{sub 2} ratio. In this study, the maximum system efficiency is 56.3%. (authors)

Ogawa, Takashi; Fujiwara, Seiji; Kasai, Shigeo; Yamada, Kazuya [Toshiba Corporation: 1 Toshiba-cho, Fuchu, Tokyo, 183-8511 (Japan)

2007-07-01

181

Development of a novel integrated continuous reactor system for biocatalytic production of biodiesel.  

PubMed

A novel integrated immobilized enzyme-reactor system involving a continuous stirred tank reactor with two packed bed reactors in series was developed for the continuous production of biodiesel. The problem of methanol solubility into oil was solved by introducing a stirred tank reactor to dissolve methanol into partially converted oil. This step made the process perfectly continuous without requiring any organic solvent and intermittent methanol addition in the process. The substrate feeding rate of 0.74mL/min and enzyme loading of 0.75g per reactor were determined to be optimum for maximum biodiesel yield. The integrated continuous process was stable up to 45 cycles with biodiesel productivity of 137.2g/L/h, which was approximately 5 times higher than solvent free batch process. In comparison with the processes reported in literature using expensive Novozyme 435 and hazardous organic solvent, the present process is completely green and perfectly continuous with economic and environmental advantages. PMID:24001564

Chattopadhyay, Soham; Sen, Ramkrishna

2013-08-12

182

Calculation of fission products release from pebble-bed reactors  

Microsoft Academic Search

Thesis. Using a two-region diffusion model, fission product release ; from coated particles is calculated under simplified assumptions. With the help ; of Laplace-transforms the time-dependent diffusion equations are solved with ; suitable boundary conditions. A second solution is based on the application of ; Green's functions. Both methods yield the same results. Knowing the temperature ; distribution throughout the

Herhadi

1972-01-01

183

Horizontal reactor for the continuous production of ethanol by yeasts immobilized in pectin  

Microsoft Academic Search

Yeast cells (Saccharomyces cerevisiae) were immobilized in pectin gel, incubated 12 h at 30°C and then used for the continuous production of ethanol employing a wedge-shaped horizontal reactor and sugar cane molasses as the carbon source. Under steady state conditions the mean residence time was 1.6 h and the volumetric productivity 40 g EtOH\\/hl. The gas evolved was easily released.

Antonio Navarro; Hugo Marangoni; Ignacio Magaña Plaza; Danley Callieri

1984-01-01

184

l(?)Carnitine production with immobilized Escherichia coli cells in continuous reactors  

Microsoft Academic Search

Escherichia coli 044 K74 was able to biotransform trans-crotonobetaine to l(?)-carnitine in continuous packed-bed reactors with cells immobilized in glass beads or polyurethane foams. Fumarate was added to the medium used for growth to increase both the carnitine production rate and carnitine yield. Although high productivities close to 2 g l?1h?1 were obtained with both supports, carnitine yields of 26%

JoséMaría Obón; Juan Ramón Maiquez; Manuel Canovas; Hans-Peter Kleber; JoséLuis Iborra

1997-01-01

185

Particle characteristics in the reactor and pelletizing areas of carbon black production.  

PubMed

Physical and chemical characteristics of airborne particles (ultrafine, PM1, PM2.5, and PM10) in reactor and pelletizing areas during carbon black production were measured to assess process related sources of particles in work areas. Results from bagging areas within the same three facilities have been previously published. Particle number and mass concentration measurements were conducted in these work areas and at ambient comparison sites at each of the three carbon black plants. No elevated ultrafine particle number concentrations (UFP, <100 nm) with respect to ambient were determined in the work areas of Plant 1, intermittently elevated concentrations at Plant 2, and permanently elevated concentrations at Plant 3. The intermittently elevated UFP concentrations in the pelletizer and reactor areas of Plant 2 could be related to nearby traffic emissions. The ultrafine particle number concentrations at Plant 2 are comparable to those determined at urban traffic sites. Both work areas of Plant 3 showed elevated UFP concentrations in the pelletizer reactor and areas. In the case of the reactor, which was the only enclosed reactor area investigated among the three facilities, the source of the elevated UFP number concentration was most likely attributable to grease and oil fumes from maintenance activities, a conclusion supported by carbon fractionation analysis. The elevated UFP number concentrations in the pelletizing area in this same plant are related to leaks in the production line, which allowed particulate matter to escape to the surrounding areas. Absolute PM10 mass concentrations were all within normal ambient concentrations except for the pelletizing area in Plant 3, which showed continuous levels above ambient. One additional source contributing to peak level PM10 mass concentrations at Plant 2 was due to wind dispersion from a carbon black spill incident the day prior to measurements. It is concluded from these measurements that no carbon black is released in the reactor and pelletizing areas (as UFP or PM10) from the closed production lines under normal operating conditions. PMID:16998988

Kuhlbusch, T A J; Fissan, H

2006-10-01

186

Control of an anaerobic reactor towards maximum biogas production  

Microsoft Academic Search

A new control strategy is introduced for operating anaerobic digestion processes efficiently at high load. The control system includes a cascade controller embedded into a rule-based supervisory system based on extremum-seeking control. The control system measures pH and biogas production rate and varies the organic load by manipulating the influent flow. Good control performances were achieved during the start-up and

J. Liu; G. Olsson; B. Mattiasson

187

A two-stage enzymatic ethanol-based biodiesel production in a packed bed reactor.  

PubMed

A two-stage enzymatic process for producing fatty acid ethyl ester (FAEE) in a packed bed reactor is reported. The process uses an experimental immobilized lipase (NS 88001) and Novozym 435 to catalyze transesterification (first stage) and esterification (second stage), respectively. Both stages were conducted in a simulated series of reactors by repeatedly passing the reaction mixture through a single reactor, with separation of the by-product glycerol and water between passes in the first and second stages, respectively. The second stage brought the major components of biodiesel to 'in-spec' levels according to the European biodiesel specifications for methanol-based biodiesel. The highest overall productivity achieved in the first stage was 2.52 kg FAEE(kg catalyst)?¹ h?¹ at a superficial velocity of 7.6 cm min?¹, close to the efficiency of a stirred tank reactor under similar conditions. The overall productivity of the proposed two-stage process was 1.56 kg FAEE(kg catalyst)?¹ h?¹. Based on this process model, the challenges of scale-up have been addressed and potential continuous process options have been proposed. PMID:22728395

Xu, Yuan; Nordblad, Mathias; Woodley, John M

2012-06-21

188

Medical isotope production: A new research initiative for the Annular Core Research Reactor  

SciTech Connect

An investigation has been performed to evaluate the capabilities of the Annular Core Research Reactor and its supporting Hot Cell Facility for the production of {sup 99}Mo and its separation from the fission product stream. Various target irradiation locations for a variety of core configurations were investigated, including the central cavity, fuel and reflector locations, and special target configurations outside the active fuel region. Monte Carlo techniques, in particular MCNP using ENDF B-V cross sections, were employed for the evaluation. The results indicate that the reactor, as currently configured, and with its supporting Hot Cell Facility, would be capable in meeting the current US demand if called upon. Modest modifications, such as increasing the capacity of the external heat exchangers, would permit significantly higher continuous power operation and even greater {sup 99}Mo production ensuring adequate capacity for future years.

Coats, R.L.; Parma, E.J.

1993-12-31

189

Multipurpose Small Size Fast Reactor: Its Basic Concept and Application to Nuclear Hydrogen Production  

SciTech Connect

Here we propose a basic concept of a multipurpose small-sized fast reactor and its applicability to produce nuclear hydrogen for near future mass use of hydrogen industrial and public use. The modular-type fast reactor of 150 MW thermal output does not require fuel exchange nor decommissioning on the site, and can be transported from the factory in a fabricated form. For the hydrogen production, we propose to use the sorption enhanced reforming process (SERP), in which the steam-methane reforming can take place around 450 - 550. Since this temperature range is rather low compared to the ongoing steam reforming method (> 800 ), the SERP system combined with an adequate nuclear reactor system should be a promising one to cope with the coming age of hydrogen civilization. (authors)

Endo, H. [Toshiba Corporation (Japan); Sawada, T.; Ninokata, H. [Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8550 (Japan)

2002-07-01

190

Production of mouse interleukin-12 is greater in tobacco hairy roots grown in a mist reactor than in an airlift reactor.  

PubMed

We compared the growth and productivity of a tobacco line of hairy roots that produces murine interleukin 12 (mIL-12) grown in three different culture systems: shake flasks, an airlift reactor, and a scalable mist reactor. Of the total mIL-12 produced by cultures grown in shake flasks ( approximately 434.8 microg L(-1)), almost 21% was recovered from the medium. In contrast to roots harvested from shake flasks and the mist reactor, roots were not uniformly distributed in the airlift reactor. Roots formed a dense ring around the wall of the reactor and surrounding the central rising column of fine aeration bubbles. Root quality was also better in both the shake flasks and mist reactor than in the airlift reactor. There were more pockets of dark roots in the airlift reactor suggesting some of the roots were nutrient starved. Although the best root growth (7 g DW L(-1)) was in the shake flasks, both reactors produced about the same, but less dry mass, nearly 5 g DW L(-1). Total mIL-12 concentration was highest in the mist reactor at 5.3 microg g(-1) FW, but productivity, 31 microg g(-1) FW day(-1) was highest in shake flasks. Roots grown in the mist reactor produced about 49.5% more mIL-12 than roots grown in the airlift reactor. Protease activity in the media increased steadily during culture of the roots in all three systems. The comparisons of protease activity, protein and mIL-12 levels done in the shake flask system suggest that the increase in proteases associated with progression into stationary phase is most detrimental to mIL-12 concentration. This is the first description of the design and operation of a scalable version of a mist bioreactor that uses a plastic bag. This also the first report of reasonable production levels of functional mIL-12, or any protein, produced by hairy roots grown in a mist reactor. Results will prove useful for further optimization and scale-up studies of plant-produced therapeutic proteins. PMID:18988263

Liu, Chunzhao; Towler, Melissa J; Medrano, Giuliana; Cramer, Carole L; Weathers, Pamela J

2009-03-01

191

Radioisotope research, production, and processing at the University of Missouri Research Reactor  

SciTech Connect

The University of Missouri Research Reactor (MURR) is a 10 MW, light-water-cooled and moderated research reactor which first achieved criticality in 1996 and is currently the highest powered university-owned research reactor in the U.S. For many years a major supplier of reactor-produced isotopes for research and commercial purposes, in the last 15 years MURR has concentrated on development of reactor-produced beta-particle emitters for experimental use in nuclear medicine therapy of cancer and rheumatoid arthritis. MURR has played a major role in the development of bone cancer pain palliation with the agents {sup 153}Sm EDTMP and {sup 186}Re/{sup 188}Re HEDP, as well as in the use of {sup 186}Re, {sup 177}Lu, {sup 166}Ho, and {sup 105}Rh for radioimmunotherapy and receptor-agent-guided radiotherapy. MURR is also responsible for the development of therapeutic, {sup 90}Y-labeled glass microspheres for the treatment of liver tumors, a product ({sup 90}Y Therasphere{trademark}) which is currently an approved drug in Canada. MURR has also pioneered the development of {sup 188}W/{sup 188}Re and {sup 99}Mo/{sup 99m}Tc gel generators, which make the use of low specific activity {sup 188}W and {sup 99}Mo practical for such isotope generators.

Ehrhardt, G.J.; Ketring, A.R.; Ja, Wei; Ma, D.; Zinn, K.; Lanigan, J.

1995-12-31

192

A review of existing gas-cooled reactor circulators with application of the lessons learned to the new production reactor circulators  

Microsoft Academic Search

This report presents the results of a study of the lessons learned during the design, testing, and operation of gas-cooled reactor coolant circulators. The intent of this study is to identify failure modes and problem areas of the existing circulators so this information can be incorporated into the design of the circulators for the New Production Reactor (NPR)-Modular High-Temperature Gas

1990-01-01

193

A scalable membrane gradostat reactor for enzyme production using Phanerochaete chrysosporium.  

PubMed

This is the first demonstration of process scale-up of a membrane gradostat reactor for continuous enzyme production using Phanerochaete chrysosporium ME446. The fungus was immobilised by reverse filtration on to externally unskinned, ultrafiltration capillary membranes and then nutrient gradients were induced across the biofilm. A 10-fold scale-up from a single capillary bioreactor to a 2.4 l multi-capillary unit resulted in a 7-fold increase in enzyme productivity with a peak at 209 U l(-1) d(-1). Subsequent scale effects on the spore distribution, continuous manganese peroxidase production profile and biofilm development are discussed. PMID:12882287

Govender, S; Jacobs, E P; Leukes, W D; Pillay, V L

2003-01-01

194

Technical and economic evaluation of different reactors for methanotrophic cultures for propylene oxide production  

Microsoft Academic Search

A two-stage process for the manufacture of propylene oxide is described. The preliminary economics based on use of methanol\\u000a as a regeneration factor has resulted in a production cost of $12.10\\/lb of propylene oxide based on propylene oxide production\\u000a rate of 40 mg\\/g-cell\\/h in conventional reactor. Increasing the propylene oxide production from 40 to 500 mg\\/g-cell\\/h resulted\\u000a in a cost

Bhupendra K. Soni; Robert L. Kelley; Vipul J. Srivastava

1998-01-01

195

Knowledges and abilities catalog for nuclear power plant operators: Savannah River Site (SRS) production reactors  

SciTech Connect

The Knowledges and Abilities Catalog for Nuclear Power Plant Operations: Savannah River Site (SRS) Production Reactors, provides the basis for the development of content-valid certification examinations for Senior Reactor Operators (SROs) and Central Control Room Supervisors (SUP). The position of Shift Technical Engineer (STE) has been included in the catalog for completeness. This new SRS reactor operating shift crew position is held by an individual holding a CCR Supervisor Certification who has received special engineering and technical training. Also, the STE has a Bachelor of Science degree in engineering or a related technical field. The SRS catalog contains approximately 2500 knowledge and ability (K/A) statements for SROs and SUPs at heavy water moderated production reactors. Each K/A statement has been rated for its importance to the safe operation of the plant in a manner ensuring the health and safety of the public. The SRS K/A catalog is presently organized into five major sections: Plant Systems grouped by Safety Function, Plant Wide Generic K/As, Emergency Plant Evolutions, Theory and Components (to be developed).

Not Available

1990-06-20

196

Materials experience and selection for nuclear materials production reactor heat exchangers  

SciTech Connect

The primary coolant systems for the heavy-water nuclear materials production reactors at the Savannah River Site are coupled to the secondary coolant systems through shell and tube heat exchangers. The head, shell, and tube sheets of these heat exchangers are fabricated from AISI Type 304 grades of austenitic stainless steel. The 8,957 tubes in each heat exchanger were originally fabricated from Type 304 stainless steel, but service experience has lead to the use of Sea Cure tubing in newer systems. The design includes double tube sheets, core rods, and 33,410 square feet of heat transfer surface. Tubes are rolled into the tube sheets and seal welded after rolling. The tubes contain Type 304 stainless steel rods which are positioned in the center of each tube axis to increase the fraction of the cooling water contacting the heat transfer surface. Each reactor utilizes twelve heat exchangers; thus the 120+ reactor-years of operating experience provide approximately 1,440 heat exchanger-years of service. Fatigue, stress corrosion cracking, crevice corrosion, and pitting have been observed during the service life. This paper describes the observed degradation processes and uses the operational experience to recommend materials for the Heavy Water -- New Production Reactor (HW-NPR).

Marra, J.E.; Louthan, M.R. Jr.

1990-01-01

197

Ethanol production in a multimembrane bioreactor: Cell and reactor modeling and continuous fermentation  

SciTech Connect

A novel bioreactor, in which hydrophilic and hydrophobic membranes segregate cells, nutrient, and solvent, has been previously described. The model system studied has been ethanol production by Saccharomyces cerevisiae with tributyl phosphate as the extractive solvent. A structured, nonsegregated model of model of Saccharomyces cerevisiae, similar in philosophy to the E. coli models extensively developed at Cornell, has been constructed. The model establishes a basis for a realistic model of multi-membrane bioreactor fermentations as well as lays the groundwork for an increasingly detailed description of the cell. A model of a pressure cycled reactor has been constructed around the model of the cells. Tested against actual reactor fermentations, the model's predictions were in quantitative agreement. The model was used to computationally survey the relative utility of variations in system design and operating strategy, suggesting that increased mixing between the cell and nutrient layers and the use of a solvent with a distribution coefficient much higher than that of TBP would significantly improve productivity. The reactor has been operated continuously without failure for over 3000 hours, demonstrating that it can be run for the periods dictated by process economics. Two natural substrates were fermented in the reactor. Corn starch hydrolysate appears to be a highly suitable substrate, blackstrap molasses does not. Zymomonas mobilis was a less effective catalyst than Saccharomyces cerevisiae.

Steinmeyer, D.E.

1990-01-01

198

Technical assumption for Mo-99 production in the MARIA reactor. Feasibility study  

SciTech Connect

The main objective of U-235 irradiation is to obtain the Tc-99m isotope which is widely used in the domain of medical diagnostics. The decisive factor determining its availability, despite its short life time, is a reaction of radioactive decay of Mo-99 into Tc- 99m. One of the possible sources of molybdenum can be achieved in course of the U-235 fission reaction. The paper presents activities and the calculations results obtained upon the feasibility study on irradiation of U-235 targets for production of molybdenum in the MARIA reactor. The activities including technical assumption were focused on performing calculation for modelling of the target and irradiation device as well as adequate equipment and tools for processing in reactor. It has been assumed that the basic component of fuel charge is an aluminium cladded plate with dimensions of 40x230x1.45 containing 4.7 g U-235. The presumed mode of the heat removal generated in the fuel charge of the reactor primary cooling circuit influences the construction of installation to be used for irradiation and the technological instrumentation. The outer channel construction for irradiation has to be identical as the standard fuel channel construction of the MARIA reactor. It enables to use the existing slab and reactor mounting sockets for the fastening of the molybdenum channel as well as the cooling water delivery system. The measurement of water temperature cooling a fuel charge and control of water flow rate in the channel can also be carried out be means of the standard instrumentation of the reactor. (author)

Jaroszewicz, J.; Pytel, K.; Dabkowski, L.; Krzysztoszek, G. [Institute of Atomic Energy, 05-400 Otwock-Swierk (Poland)

2008-07-15

199

Evaluation of plastic composite-supports for enhanced ethanol production in biofilm reactors  

Microsoft Academic Search

Biofilms are a natural form of cell immobilization that result from microbial attachment to solid supports. Biofilm reactors with polypropylene composite-supports containing up to 25% (w\\/w) of various agricultural materials (corn hulls, cellulose, oat hulls, soybean hulls or starch) and nutrients (soybean flour or zein) were used for ethanol production. Pure cultures ofZymomonas mobilis, ATCC 31821 orSaccharomyces cerevisiae ATCC 24859

M Reddy Kunduru; AL Pometto

1996-01-01

200

The spatial distribution of fission product gamma-ray energy in reactor fuel elements  

Microsoft Academic Search

Thermoluminescent dosimeters were used to determine the spatial distribution of fission product gamma-ray energy deposition in pressurized water reactor (PWR) fuel under conditions similar to those of a postulated loss-of-coolant accident (LOCA). Measurements were made in a mock-up which simulated exactly the materials and dimensions of a PWR fuel element. The detectors were positioned at various positions in the UOâ

Bass; R. B. Jr

1978-01-01

201

Laccase-catalysed synthesis of coupling products of phenolic substrates in different reactors  

Microsoft Academic Search

Substrate oxidation of aromatic substances by the enzyme laccase followed by a heteromolecular coupling with a co-substrate is a promising possibility for the synthesis of new compounds. To find a suitable reactor for the effective production of new compounds, the laccase-catalysed coupling of 3-(3,4-dihydroxyphenyl)propionic acid with 4-aminobenzoic acid was investigated as a model system. Based on the kinetic parameters, a

R. Pilz; E. Hammer; F. Schauer; U. Kragl

2003-01-01

202

Optimal product distribution from laminar flow reactors: Newtonian and other power-law fluids  

Microsoft Academic Search

In tubular reactors viscous fluids are in laminar flow. For reactions in series this gives a product distribution different from either plug flow or mixed flow. More importantly, laminar flow depresses the maximum amount of intermediate that can be obtained when compared to plug flow. Here we treat the simple case of an elementary two-step mechanism:(1)[A?R?S]Three special cases of the

Keith L. Levien; Octave Levenspiel

1999-01-01

203

Radioactive Fission Product Release from Defective Light Water Reactor Fuel Elements  

Microsoft Academic Search

Results are provided of the experimental investigation of radioactive fission product (RFP) release, i.e., krypton, xenon, and iodine radionuclides from fuel elements with initial defects during long-term (3 to 5 yr) irradiation under low linear power (5 to 12 kW\\/m) and during special experiments in the VK-50 vessel-type boiling water reactor.The calculation model for the RFP release from the fuel-to-cladding

Vadim V. Konyashov; Alexander M. Krasnov

2002-01-01

204

High-temperature reactor fuel fission product release and distribution at 1600 to 1800 degrees C  

Microsoft Academic Search

The essential feature of small, modular high-temperature reactors (HTRs) is the inherent limitation in maximum accident temperature to below 1600° C combined with the ability of coated particle fuel to retain all safety-relevant fission products under these conditions. To demonstrate this ability, spherical fuel elements with modern TRISO particles are irradiated and subjected to heating tests. Even after extended heating

W. Schenk; H. Nabielek

1991-01-01

205

An industrial-size flat plate glass reactor for mass production of Nannochloropsis sp. (Eustigmatophyceae)  

Microsoft Academic Search

A flat plate (10 cm light-path), vertical reactor made of 10-mm glass plates glued together to form a 500- to 1000-l unit was developed for outdoor production of Nannochloropsis sp., one of the most promising photoautotrophic producer of eicosapentaenoic acid (20:5?3, EPA) for aquaculture. The energy inputs required for mixing and cooling the culture were calculated and the harvesting regime

Zhang Cheng-Wu; Odi Zmora; Reuven Kopel; Amos Richmond

2001-01-01

206

Neutronics analysis of water-cooled energy production blanket for a fusion–fission hybrid reactor  

Microsoft Academic Search

Neutronics calculations were performed to analyse the parameters of blanket energy multiplication factor (M) and tritium breeding ratio (TBR) in a fusion–fission hybrid reactor for energy production named FDS (Fusion-Driven hybrid System)-EM (Energy Multiplier) blanket. The most significant and main goal of the FDS-EM blanket is to achieve the energy gain of about 1GWe with self-sustaining tritium, i.e. the M

Jieqiong Jiang; Minghuang Wang; Zhong Chen; Yuefeng Qiu; Jinchao Liu; Yunqing Bai; Hongli Chen; Yanglin Hu

2010-01-01

207

Application of evaluated fission-product delayed-neutron precursor data in reactor kinetics calculations  

SciTech Connect

Evaluated fission-product yield and decay data have been used to describe 105 delayed neutron precursors explicitly in point reactor kinetics calculations. Results calculated for /sup 235/U thermal fission show that rod-drop reactivity values obtained from kinetics calculations with 6-group precursor data are considerably higher than those calculated with explicit delayed-neutron precursor data. The calculated kinetics associated with positive reactivity steps are significantly different.

Perry, R.T.; Wilson, W.B.; England, T.R.; Brady, M.C.

1985-01-01

208

Hydrogen production in a zigzag and straight catalytic wall coated micro channel reactor by CFD modeling  

Microsoft Academic Search

Hydrogen production from steam reforming of methanol for fuel cell application was modeled in a wall coated micro channel reactor by CFD approach. Heat of steam reforming (SR) was supplied from catalytic total oxidation (TOX) of methanol on Cu\\/ZnO\\/Al2O3 catalyst and Heat conducts from TOX to SR zone through Steel divider wall between two channels. Heat integration was compared in

Ali Fazeli; Mohsen Behnam

2010-01-01

209

Micro-structured nuclear fuel and novel nuclear reactor concepts for advanced power production  

Microsoft Academic Search

Many applications (e.g. terrestrial and space electric power production, naval, underwater and railroad propulsion and auxiliary power for isolated regions) require a compact-high-power electricity source. The development of such a reactor structure necessitates a deeper understanding of fission energy transport and materials behavior in radiation dominated structures. One solution to reduce the greenhouse-gas emissions and delay the catastrophic events' occurrences

Liviu Popa-Simil

2008-01-01

210

Methane production by treating vinasses from hydrous ethanol using a modified UASB reactor  

PubMed Central

Background A modified laboratory-scale upflow anaerobic sludge blanket (UASB) reactor was used to obtain methane by treating hydrous ethanol vinasse. Vinasses or stillage are waste materials with high organic loads, and a complex composition resulting from the process of alcohol distillation. They must initially be treated with anaerobic processes due to their high organic loads. Vinasses can be considered multipurpose waste for energy recovery and once treated they can be used in agriculture without the risk of polluting soil, underground water or crops. In this sense, treatment of vinasse combines the elimination of organic waste with the formation of methane. Biogas is considered as a promising renewable energy source. The aim of this study was to determine the optimum organic loading rate for operating a modified UASB reactor to treat vinasse generated in the production of hydrous ethanol from sugar cane molasses. Results The study showed that chemical oxygen demand (COD) removal efficiency was 69% at an optimum organic loading rate (OLR) of 17.05 kg COD/m3-day, achieving a methane yield of 0.263 m3/kg CODadded and a biogas methane content of 84%. During this stage, effluent characterization presented lower values than the vinasse, except for potassium, sulfide and ammonia nitrogen. On the other hand, primers used to amplify the 16S-rDNA genes for the domains Archaea and Bacteria showed the presence of microorganisms which favor methane production at the optimum organic loading rate. Conclusions The modified UASB reactor proposed in this study provided a successful treatment of the vinasse obtained from hydrous ethanol production. Methanogen groups (Methanobacteriales and Methanosarcinales) detected by PCR during operational optimum OLR of the modified UASB reactor, favored methane production.

2012-01-01

211

Modeling requirements for full-scope reactor simulators of fission-product transport during severe accidents  

SciTech Connect

This paper describes in the needs and requirements to properly and efficiently model fission product transport on full scope reactor simulators. Current LWR simulators can be easily adapted to model severe accident phenomena and the transport of radionuclides. Once adapted these simulators can be used as a training tool during operator training exercises for training on severe accident guidelines, for training on containment venting procedures, or as training tool during site wide emergency training exercises.

Ellison, P.G.; Monson, P.R. [Westinghouse Savannah River Co., Aiken, SC (United States); Mitchell, H.A. [Concord Associates, Inc., Knoxville, TN (United States)

1990-12-31

212

Modeling requirements for full-scope reactor simulators of fission-product transport during severe accidents  

SciTech Connect

This paper describes in the needs and requirements to properly and efficiently model fission product transport on full scope reactor simulators. Current LWR simulators can be easily adapted to model severe accident phenomena and the transport of radionuclides. Once adapted these simulators can be used as a training tool during operator training exercises for training on severe accident guidelines, for training on containment venting procedures, or as training tool during site wide emergency training exercises.

Ellison, P.G.; Monson, P.R. (Westinghouse Savannah River Co., Aiken, SC (United States)); Mitchell, H.A. (Concord Associates, Inc., Knoxville, TN (United States))

1990-01-01

213

Aluminum\\/uranium fuel foaming\\/recriticality considerations for production reactor core-melt accidents  

Microsoft Academic Search

Severe accident studies for the Savannah River production reactors indicate that if coherent fuel melting and relocation occur in the absence of target melting, in-vessel recriticality may be achieved. In this paper, fuel-melt\\/target interaction potential is assessed where fission gas-induced fuel foaming and melt attack on target material are evaluated and compared with available data. Models are developed to characterize

M. L. Hyder; P. G. Ellison; A. W. Cronenberg

1990-01-01

214

A1-U fuel foaming\\/recriticality considerations for production reactor core-melt accidents  

Microsoft Academic Search

Severe accident studies for the Savannah River production reactors indicate that if coherent fuel melting and relocation occur in the absence of target melting, in-vessel recriticality may be achieved. In this paper, fuel-melt\\/target interaction potential is assessed, where fission gas-induced fuel foaming and melt attach on target material are evaluated and compared with available data. Models are developed to characterize

A. W. Cronenberg; M. L. Hyder; P. G. Ellison

1990-01-01

215

Butanol production by Clostridium beijerinckii BA101 in an immobilized cell biofilm reactor: increase in sugar utilization.  

PubMed

Acetone butanol ethanol was produced in a continuous immobilized cell (biofilm) plug-flow reactor inoculated with Clostridium beijerinckii BA101. To achieve high reactor productivity, C. beijerinckii BA101 cells were immobilized by adsorption onto clay brick. The continuous plug-flow reactor offers high productivities owing to reduced butanol inhibition and increased cell concentration. Although high productivity was achieved, it was at the expense of low sugar utilization (30.3%). To increase sugar utilization, the reactor effluent was recycled. However, this approach is complicated by butanol toxicity. The effluent was recycled after removal of butanol by pervaporation to reduce butanol toxicity in the reactor. Recycling of butanol-free effluent resulted in a sugar utilization of 100.7% in addition to high productivity of 10.2 g/(L x h) at a dilution rate of 1.5 h(-1). A dilution rate of 2.0 h(-1) resulted in a reactor productivity of 16.2 g/(L x h) and sugar utilization of 101.4%. It is anticipated that this reactor-recovery system would be economical for butanol production when using C. beijerinckii BA101. PMID:12018285

Lienhardt, Jason; Schripsema, Justin; Qureshi, Nasib; Blaschek, Hans P

2002-01-01

216

Fission product release assessment for O6 mixed bundle channel feeder stagnation break in CANDU-6 reactor.  

National Technical Information Service (NTIS)

A fission product release assessment for O6 'mixed-bundle' channel feeder stagnation break in CANDU-6 reactor has been performed as one of the licensing safety analyses required for 24 natural uranium CANFLEX bundle irradiation in CANDU-6 reactor. The tot...

D. J. Oh D. Bowslaugh

1996-01-01

217

Optimization of tri-reformer reactor to produce synthesis gas for methanol production using differential evolution (DE) method  

Microsoft Academic Search

This paper presents a study on optimization of a fixed bed tri-reformer reactor (TR). This reactor has been used instead of conventional steam reformer (CSR) and auto thermal reformer (CAR). A theoretical investigation has been performed in order to evaluate the optimal operating conditions and enhancement of methane conversion, hydrogen production and desired H2\\/CO ratio as a synthesis gas for

Z. Arab Aboosadi; A. H. Jahanmiri; M. R. Rahimpour

2011-01-01

218

Production of polygalacturonases by Aspergillus section Nigri strains in a fixed bed reactor.  

PubMed

Polygalacturonases (PG) are pectinolytic enzymes that have technological, functional and biological applications in food processing, fruit ripening and plant-fungus interactions, respectively. In the present, a microtitre plate methodology was used for rapid screening of 61 isolates of fungi from Aspergillus section Nigri to assess production of endo- and exo-PG. Studies of scale-up were carried out in a fixed bed reactor operated under different parameters using the best producer strain immobilised in orange peels. Four experiments were conducted under the following conditions: the immobilised cells without aeration; immobilised cells with aeration; immobilised cells with aeration and added pectin; and free cells with aeration. The fermentation was performed for 168 h with removal of sample every 24 h. Aspergillus niger strain URM 5162 showed the highest PG production. The results obtained indicated that the maximum endo- and exo-PG activities (1.18 U ? mL-1 and 4.11 U ? mL-1, respectively) were obtained when the reactor was operating without aeration. The microtitre plate method is a simple way to screen fungal isolates for PG activity detection. The fixed bed reactor with orange peel support and using A. niger URM 5162 is a promising process for PG production at the industrial level. PMID:23358324

Maciel, Marília; Ottoni, Cristiane; Santos, Cledir; Lima, Nelson; Moreira, Keila; Souza-Motta, Cristina

2013-01-28

219

Fuel and core testing plan for a target fueled isotope production reactor.  

SciTech Connect

In recent years there has been an unstable supply of the critical diagnostic medical isotope 99Tc. Several concepts and designs have been proposed to produce 99Mo the parent nuclide of 99Tc, at a commercial scale sufficient to stabilize the world supply. This work lays out a testing and experiment plan for a proposed 2 MW open pool reactor fueled by Low Enriched Uranium (LEU) 99Mo targets. The experiments and tests necessary to support licensing of the reactor design are described and how these experiments and tests will help establish the safe operating envelop for a medical isotope production reactor is discussed. The experiments and tests will facilitate a focused and efficient licensing process in order to bring on line a needed production reactor dedicated to supplying medical isotopes. The Target Fuel Isotope Reactor (TFIR) design calls for an active core region that is approximately 40 cm in diameter and 40 cm in fuel height. It contains up to 150 cylindrical, 1-cm diameter, LEU oxide fuel pins clad with Zircaloy (zirconium alloy), in an annular hexagonal array on a {approx}2.0 cm pitch surrounded, radially, by a graphite or a Be reflector. The reactor is similar to U.S. university reactors in power, hardware, and safety/control systems. Fuel/target pin fabrication is based on existing light water reactor fuel fabrication processes. However, as part of licensing process, experiments must be conducted to confirm analytical predictions of steady-state power and accident conditions. The experiment and test plan will be conducted in phases and will utilize existing facilities at the U.S. Department of Energy's Sandia National Laboratories. The first phase is to validate the predicted reactor core neutronics at delayed critical, zero power and very low power. This will be accomplished by using the Sandia Critical Experiment (CX) platform. A full scale TFIR core will be built in the CX and delayed critical measurements will be taken. For low power experiments, fuel pins can be removed after the experiment and using Sandia's metrology lab, relative power profiles (radially and axially) can be determined. In addition to validating neutronic analyses, confirming heat transfer properties of the target/fuel pins and core will be conducted. Fuel/target pin power limits can be verified with out-of-pile (electrical heating) thermal-hydraulic experiments. This will yield data on the heat flux across the Zircaloy clad and establish safety margin and operating limits. Using Sandia's Annular Core Research Reactor (ACRR) a 4 MW TRIGA type research reactor, target/fuel pins can be driven to desired fission power levels for long durations. Post experiment inspection of the pins can be conducted in the Auxiliary Hot Cell Facility to observe changes in the mechanical properties of the LEU matrix and burn-up effects. Transient tests can also be conducted at the ACRR to observe target/fuel pin performance during accident conditions. Target/fuel pins will be placed in double experiment containment and driven by pulsing the ACRR until target/fuel failure is observed. This will allow for extrapolation of analytical work to confirm safety margins.

Coats, Richard Lee; Dahl, James J.; Parma, Edward J., Jr.

2010-12-01

220

A review of existing gas-cooled reactor circulators with application of the lessons learned to the new production reactor circulators  

SciTech Connect

This report presents the results of a study of the lessons learned during the design, testing, and operation of gas-cooled reactor coolant circulators. The intent of this study is to identify failure modes and problem areas of the existing circulators so this information can be incorporated into the design of the circulators for the New Production Reactor (NPR)-Modular High-Temperature Gas Cooled Reactor (MHTGR). The information for this study was obtained primarily from open literature and includes data on high-pressure, high-temperature helium test loop circulators as well as the existing gas cooled reactors worldwide. This investigation indicates that trouble free circulator performance can only be expected when the design program includes a comprehensive prototypical test program, with the results of this test program factored into the final circulator design. 43 refs., 7 tabs.

White, L.S.

1990-07-01

221

Advances in biofilm reactors for production of value-added products  

Microsoft Academic Search

Biofilms are defined as microbial cell layers, which are irreversibly or reversibly attached on solid surfaces. These attached\\u000a cells are embedded in a self-produced exopolysaccharide matrix, and exhibit different growth and bioactivity compared with\\u000a suspended cells. With their high biomass density, stability, and potential for long-term fermentation, biofilm reactors are\\u000a employed for the fermentation and bioconversion, which need large amount

Kuan-Chen Cheng; Ali Demirci; Jeffrey M. Catchmark

2010-01-01

222

Experiments and analysis of fission product release in HEU-fuelled SLOWPOKE-2 reactors  

NASA Astrophysics Data System (ADS)

Fission product activity levels have been measured using a transportable gamma ray spectroscopy system at four SLOWPOKE-2 facilities. Through an analysis of the concentrations of these radionuclides in samples of the reactor coolant and gas headspace, the rate of release from the fuel has been determined by a Savitzky-Golay method and also by a non-linear least squares method. The release rate calculation has been validated against the mainframe code SUMRT. By examining the release rates, the source of the short-lived fission products is determined to be direct recoil from exposed uranium-bearing surfaces.

Harnden-Gillis, A. C.; Bennett, L. G. I.; Lewis, B. J.

1994-07-01

223

Hydrogen production from rice winery wastewater in an upflow anaerobic reactor by using mixed anaerobic cultures  

Microsoft Academic Search

Continuous production of hydrogen from the anaerobic acidogenesis of a high-strength rice winery wastewater by a mixed bacterial flora was demonstrated. The experiment was conducted in a 3.0-l upflow reactor to investigate individual effects of hydraulic retention time (HRT) (2–24h), chemical oxygen demand (COD) concentration in wastewater (14–36g COD\\/l), pH (4.5–6.0) and temperature (20–55°C) on bio-hydrogen production from the wastewater.

Hanqing Yu; Zhenhu Zhu; Wenrong Hu; Haisheng Zhang

2002-01-01

224

Chemistry of Sodium Coolant. Impurities of Nuclear Fuel and Its Fission Products in Sodium Coolant of Fast Reactors.  

National Technical Information Service (NTIS)

Properties of impurities of nuclear fuel and its fission products and their behaviour in sodium coolant of the primary circuit of fast reactors are considered. The impurities are classified with account of their properties, behaviour in the circuit and si...

E. E. Konovalov A. I. Lastov P. S. Otstavnov

1982-01-01

225

Joule-Heated Molten Regolith Electrolysis Reactor Concepts for Oxygen and Metals Production on the Moon and Mars.  

National Technical Information Service (NTIS)

The maturation of Molten Regolith Electrolysis (MRE) as a viable technology for oxygen and metals production on explored planets relies on the realization of the self-heating mode for the reactor. Joule heat generated during regolith electrolysis creates ...

J. A. Dominques L. Sibille

2012-01-01

226

Production of polygalacturonases by Aspergillus oryzae in stirred tank and internal- and external-loop airlift reactors.  

PubMed

The production of endo- and exo-polygalacturonase (PG) by Aspergillus oryzae was assessed in stirred tank reactors (STRs), internal-loop airlift reactors (ILARs) and external-loop airlift reactors (ELARs). For STR production, we compared culture media formulated with either pectin (WBE) or partially hydrolyzed pectin. The highest enzyme activities were obtained in medium that contained 50% pectin in hydrolyzed form (WBE5). PG production in the three reactor types was compared for WBE5 and low salt WBE medium, with additional salts added at 48, 60 and 72h (WBES). The ELARs performed better than the ILARs in WBES medium where the exo-PG was the same concentration as for STRs and the endo-PG was 20% lower. These results indicate that PG production is higher under experimental conditions that result in higher cell growth with minimum pH values less than 3.0. PMID:22940313

Fontana, Roselei Claudete; da Silveira, Maurício Moura

2012-07-24

227

Novel Membrane Reactor for Direct Hydrogen Production from Coal. (Quarterly Report, April 1, 2005-June 30, 2005).  

National Technical Information Service (NTIS)

Gas Technology Institute is developing a novel concept of membrane reactor coupled with a gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification react...

S. Doong E. Ong M. Atroshenko F. Lau M. Roberts

2005-01-01

228

Novel Membrane Reactor for Direct Hydrogen Production from Coal. (Quarterly Report, April 2, 2004-June 30, 2005).  

National Technical Information Service (NTIS)

Gas Technology Institute is developing a novel concept of membrane reactor coupled with a gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification react...

S. Doong E. Ong M. Atroshenko F. Lau M. Roberts

2005-01-01

229

Assessment of fission product yields data needs in nuclear reactor applications  

SciTech Connect

Studies on the build-up of fission products in fast reactors have been performed, with particular emphasis on the effects related to the physics of the nuclear fission process. Fission product yields, which are required for burn-up calculations, depend on the proton and neutron number of the target nucleus as well as on the incident neutron energy. Evaluated nuclear data on fission product yields are available for all relevant target nuclides in reactor applications. However, the description of their energy dependence in evaluated data is still rather rudimentary, which is due to the lack of experimental fast fission data and reliable physical models. Additionally, physics studies of evaluated JEFF-3.1.1 fission yields data have shown potential improvements, especially for various fast fission data sets of this evaluation. In recent years, important progress in the understanding of the fission process has been made, and advanced model codes are currently being developed. This paper deals with the semi-empirical approach to the description of the fission process, which is used in the GEF code being developed by K.-H. Schmidt and B. Jurado on behalf of the OECD Nuclear Energy Agency, and with results from the corresponding author's diploma thesis. An extended version of the GEF code, supporting the calculation of spectrum weighted fission product yields, has been developed. It has been applied to the calculation of fission product yields in the fission rate spectra of a MOX fuelled sodium-cooled fast reactor. Important results are compared to JEFF-3.1.1 data and discussed in this paper. (authors)

Kern, K.; Becker, M.; Broeders, C. [Institut fuer Neutronenphysik und Reaktortechnik, KIT Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Leopoldshafen (Germany)

2012-07-01

230

Feasibility study Part I - Thermal hydraulic analysis of LEU target for {sup 99}Mo production in Tajoura reactor  

SciTech Connect

The Renewable Energies and Water Desalination Research Center (REWDRC), Libya, will implement the technology for {sup 99}Mo isotope production using LEU foil target, to obtain new revenue streams for the Tajoura nuclear research reactor and desiring to serve the Libyan hospitals by providing the medical radioisotopes. Design information is presented for LEU target with irradiation device and irradiation Beryllium (Be) unit in the Tajoura reactor core. Calculated results for the reactor core with LEU target at different level of power are presented for steady state and several reactivity induced accident situations. This paper will present the steady state thermal hydraulic design and transient analysis of Tajoura reactor was loaded with LEU foil target for {sup 99}Mo production. The results of these calculations show that the reactor with LEU target during the several cases of transient are in safe and no problems will occur. (author)

Bsebsu, F.M.; Abotweirat, F. [Reactor Department, Renewable Energies and Water Desalination Research Cente, P.O. Box 30878 Tajoura, Tripoli (Libyan Arab Jamahiriya)], E-mail: Bsebso@yahoo.com, E-mail: abutweirat@yahoo.com; Elwaer, S. [Radiochemistry Department, Renewable Energies and Water Desalination Research Cente, P.O. Box 30878 Tajoura, Tripoli (Libyan Arab Jamahiriya)], E-mail: samiwer@yahoo.com

2008-07-15

231

Modular Hybrid Plasma Reactor for Low Cost Bulk Production of Nanomaterials  

SciTech Connect

INL developed a bench scale modular hybrid plasma system for gas phase nanomaterials synthesis. The system was being optimized for WO3 nanoparticles production and scale model projection to a 300 kW pilot system. During the course of technology development many modifications had been done to the system to resolve technical issues that had surfaced and also to improve the performance. All project tasks had been completed except 2 optimization subtasks. These 2 subtasks, a 4-hour and an 8-hour continuous powder production runs at 1 lb/hr powder feeding rate, were unable to complete due to technical issues developed with the reactor system. The 4-hour run had been attempted twice and both times the run was terminated prematurely. The modular electrode for the plasma system was significantly redesigned to address the technical issues. Fabrication of the redesigned modular electrodes and additional components had been completed at the end of the project life. However, not enough resource was available to perform tests to evaluate the performance of the new modifications. More development work would be needed to resolve these problems prior to scaling. The technology demonstrated a surprising capability of synthesizing a single phase of meta-stable delta-Al2O3 from pure alpha-phase large Al2O3 powder. The formation of delta-Al2O3 was surprising because this phase is meta-stable and only formed between 973-1073 K, and delta-Al2O3 is very difficult to synthesize as a single phase. Besides the specific temperature window to form this phase, this meta-stable phase may have been stabilized by nanoparticle size formed in a high temperature plasma process. This technology may possess the capability to produce unusual meta-stable nanophase materials that would be otherwise difficult to produce by conventional methods. A 300 kW INL modular hybrid plasma pilot scale model reactor had been projected using the experimental data from PPG Industries 300 kW hot wall plasma reactor. The projected size of the INL 300 kW pilot model reactor would be about 15% that of the PPG 300 kW hot wall plasma reactor. Including the safety net factor the projected INL pilot reactor size would be 25-30% of the PPG 300 kW hot wall plasma pilot reactor. Due to the modularity of the INL plasma reactor and the energy cascading effect from the upstream plasma to the downstream plasma the energy utilization is more efficient in material processing. It is envisioning that the material through put range for the INL pilot reactor would be comparable to the PPG 300 kW pilot reactor but the energy consumption would be lower. The INL hybrid plasma technology is rather close to being optimized for scaling to a pilot system. More near term development work is still needed to complete the process optimization before pilot scaling.

Peter C. Kong

2011-12-01

232

Inulinase production in a packed bed reactor by solid state fermentation.  

PubMed

In this work, production of inulinase was carried out in a packed bed reactor (PBR) under solid state fermentation. Kluyveromyces marxianus var. marxianus was used to produce the inulinase using pressmud as substrate. The parameters like air flow rate, packing density and particle size were optimized using response surface methodology (RSM) to maximize the inulinase production. The optimum conditions for the maximum inulinase production were: air flow rate - 0.82 L/min, packing density - 40 g/L and particle size - 0.0044 mm (mesh - 14/20). At these optimized conditions, the production of inulinase was found to be 300.5 unit/gram of dry substrate (U/gds). PMID:23688470

Dilipkumar, M; Rajamohan, N; Rajasimman, M

2013-04-03

233

Butanol production by bioconversion of cheese whey in a continuous packed bed reactor.  

PubMed

Butanol production by Clostridium acetobutylicum DSM 792 fermentation was investigated. Unsupplemented cheese whey was adopted as renewable feedstock. The conversion was successfully carried out in a biofilm packed bed reactor (PBR) for more than 3 months. The PBR was a 4 cm ID, 16 cm high glass tube with a 8 cm bed of 3mm Tygon rings, as carriers. It was operated at the dilution rate between 0.4h(-1) and 0.94 h(-1). The cheese whey conversion process was characterized in terms of metabolites production (butanol included), lactose conversion and biofilm mass. Under optimized conditions, the performances were: butanol productivity 2.66 g/Lh, butanol concentration 4.93 g/L, butanol yield 0.26 g/g, butanol selectivity of the overall solvents production 82 wt%. PMID:23619138

Raganati, F; Olivieri, G; Procentese, A; Russo, M E; Salatino, P; Marzocchella, A

2013-04-04

234

A model for nonvolatile fission product release during reactor accident conditions  

SciTech Connect

An analytical model has been developed to describe the release kinetics of nonvolatile fission products (e.g., molybdenum, cerium, ruthenium, and barium) from uranium dioxide fuel under severe reactor accident conditions. This treatment considers the rate-controlling process of release in accordance with diffusional transport in the fuel matrix and fission product vaporization from the fuel surface into the surrounding gas atmosphere. The effect of the oxygen potential in the gas atmosphere on the chemical form and volatility of the fission product is considered. A correlation is also developed to account for the trapping effects of antimony and tellurium in the Zircaloy cladding. This model interprets the release behavior of fission products observed in Commissariat a l`Energie Atomique experiments conducted in the HEVA/VERCORS facility at high temperature in a hydrogen and steam atmosphere.

Lewis, B.J.; Andre, B.; Ducros, G. [CEA Centre d`Etudes Nucleaires, Grenoble (France); Maro, D. [CEA Centre d`Etudes Nucleaires, Fontenay aux Roses (France)

1996-10-01

235

Richland Environmental Restoration Project Fiscal Year 2000-2002 Detailed Work Plan - Remedial Action and Waste Disposal Project  

Microsoft Academic Search

The U. S. Department of Energy (DOE), Richland Operations Office (RL), directed Hanford Site contractors to update multi-year work plans in accordance with the guidance provided to them. The Richland Environmental Restoration Project continued the Detailed Work Plan update approach that was approved in fiscal year 1998. This Detailed Work Plan provides the cost, scope, and schedule for the FY00

L. D. Dillon

1999-01-01

236

Reservoir characterization of the Mississippian Ratcliffe, Richland County, Montana, Williston Basin. Topical report, September 1997  

SciTech Connect

This topical report is a compilation of characterizations by different disciplines of the Mississippian Ratcliffe in portions of Richland County, MT. Goals of the report are to increase understanding of the reservoir rocks, oil-in-place, heterogeneity and methods for improved recovery. The report covers investigations of geology, petrography, reservoir engineering and seismic. The Ratcliffe is a low permeability oil reservoir which appears to be developed across much of the study area and occurs across much of the Williston Basin. The reservoir has not been a primary drilling target in the study area because average reserves have been insufficient to payout the cost of drilling and completion despite the application of hydraulic fracture stimulation. Oil trapping does not appear to be structurally controlled. For the Ratcliffe to be a viable drilling objective, methods need to be developed for (1) targeting better reservoir development and (2) better completions. A geological model is presented for targeting areas with greater potential for commercial reserves in the Ratcliffe. This model can be best utilized with the aid of 3D seismic. A 3D seismic survey was acquired and is used to demonstrate a methodology for targeting the Ratcliffe. Other data obtained during the project include oriented core, special formation-imaging log, pressure transient measurements and oil PVT. Although re-entry horizontal drilling was unsuccessfully tested, this completion technology should improve the economic viability of the Ratcliffe. Reservoir simulation of horizontal completions with productivity of three times that of a vertical well suggested two or three horizontal wells in a 258-ha (640-acre) area could recover sufficient reserves for profitable drilling.

Sippel, M.; Luff, K.D.; Hendricks, M.L.

1998-07-01

237

Ammonium recovery from reject water combined with hydrogen production in a bioelectrochemical reactor.  

PubMed

In this study, a bioelectrochemical reactor was investigated for simultaneous hydrogen production and ammonium recovery from reject water, which is an ammonium-rich side-stream produced from sludge treatment processes at wastewater treatment plants. In the anode chamber of the reactor, microorganisms converted organic material into electrical current. The electrical current was used to generate hydrogen gas at the cathode with 96±6% efficiency. Real or synthetic reject water was fed to the cathode chamber where proton reduction into hydrogen gas resulted in a pH increase which led to ammonium being converted into volatile ammonia. The ammonia could be stripped from the solution and recovered in acid. Overall, ammonium recovery efficiencies reached 94% with synthetic reject water and 79% with real reject water. This process could potentially be used to make wastewater treatment plants more resource-efficient and further research is warranted. PMID:23973971

Wu, Xue; Modin, Oskar

2013-08-02

238

Differential evolution (DE) strategy for optimization of hydrogen production, cyclohexane dehydrogenation and methanol synthesis in a hydrogen-permselective membrane thermally coupled reactor  

Microsoft Academic Search

In this work a novel reactor configuration has been proposed for simultaneous methanol synthesis, cyclohexane dehydrogenation and hydrogen production. This reactor configuration is a membrane thermally coupled reactor which is composed of three sides for methanol synthesis, cyclohexane dehydrogenation and hydrogen production. Methanol synthesis takes place in the exothermic side that supplies the necessary heat for the endothermic dehydrogenation of

M. H. Khademi; M. R. Rahimpour; A. Jahanmiri

2010-01-01

239

Evaluation of injury/illness recordkeeping pilot course taught in Richland, Washington, June 18, 1992  

SciTech Connect

This report summarizes trainee evaluations for the Safety Training Section course, Injury/Illness Recordkeeping which was conducted June 18, at Hanford, in richland, Washington. This class was the second pilot course taught. This class was designed to aquaint attendees with DOE orders 5484.1, 5484.1A, draft 3 and OSHA regulations found in 29 CFR 1904.

Wright, T.S.

1992-11-01

240

Correlation of Late Genozoic Gravel Deposits along the Yakima River Drainage from Ellensburg to Richland  

Microsoft Academic Search

Gravel deposits are sampled for clast lithology at fifty-seven sites along the Yakima River from Thoi} to Richland, \\\\fashington. One hundred clasrs, io each of three different sizes, are identified from each site. These are divided into five Iithologic groulx: basatt, andesite, grnniric, metamorphic, and sedimentary. cravels from the modern Yakima River, three Yalima Rivir rerraces, the Eileniburg Formation, and

241

Startup of the FFTF sodium cooled reactor  

SciTech Connect

The Fast Flux Test Facility (FFTF), located on the Department of Energy (DOE) Hanford Reservation near Richland, Washington, is a 3 Loop 400 MWt sodium cooled fast reactor with a primary mission to test fuels and materials for development of the Liquid Metal Fast Breeder Reactor (LMFBR). Highlights of the ATP involving the system inerting, liquid metal and inerted cell testing and initial ascent to full power are discussed. 3 refs.

Umek, A.M.; Redekopp, R.D.

1981-08-01

242

Pipe break testing of primary loop piping similar to Department of Energy`s New Production Reactor-Heavy Water Reactor  

SciTech Connect

The subject of this paper is to review the recent failure testing of the Savannah River C-reactor piping weldment, which will be referred to as the C-pipe in the remainder of the paper. The intent of this paper is to further familiarize the technical community with Oak Ridge National Laboratory`s (ORNL) pipe test program and associated activities surrounding the C-pipe test as conducted on behalf of the Department of Energy New Production Reactor (DOE-NPR) Program.

Poole, A.B.; Clinard, J.A.; Battiste, R.L.; Hendrich, W.R.

1993-05-01

243

Production of tomato flavor volatiles from a crude enzyme preparation using a hollow-fiber reactor.  

PubMed

In recent years there has been an increase in the interest in the production of compounds by isolation from natural sources or through processes that can be deemed "natural". This is of particular interest in the food and beverage industry for flavors and aromas. Hexanal, organoleptically known to possess "green character", is of considerable commercial interest. The objective of this study was to determine if the enzyme template known to be responsible for the synthesis of hexanal from linoleic acid (18:2) in tomato fruits could be harnessed using a hollow-fiber reactor. A hollow-fiber reactor system was set up and consisted of a XAMPLER ultrafiltration module coupled to a reservoir. The enzyme template was extracted from ripe tomato fruits and processed through an ultrafiltration unit (NMWC of 100 kDa) to produce a retentate enriched in soluble and membrane-associated lipoxygenase (LOX) and hydroperoxide lyase (HPL). This extract was recirculated through the lumen of the hollow-fiber ultrafiltration unit with the addition of substrate in the form of linoleic acid, with buffer addition to the reaction flask to maintain a constant retentate volume. Product formation was measured in the permeate using solid phase microextraction (SPME) developed for this system. At exogenous substrate concentrations of 16 mM and a transmembrane pressure of 70 kPa, hexanal production rates are in the order of 5.1 microg/min. Addition of Triton X-100 resulted in membrane fouling and reduced flux. The reactor system has been run for periods of up to 1 week and has been shown to be stable over this period. PMID:10620268

Cass, B J; Schade, F; Robinson, C W; Thompson, J E; Legge, R L

2000-02-01

244

Enzymatic production of hydrogen peroxide and acetaldehyde in a pressure reactor.  

PubMed

Alcohol oxidase, an enzyme which exhibits relatively weak substrate specificity among short chain alcohols, forms the corresponding aldehyde and hydrogen peroxide as coproduct. The ability of alcohol oxidase from Pichia pastoris yeast to convert ethanol to acetaldehyde and hydrogen peroxide was examined in an oxygen pressure reactor under conditions, such that oxygen availability was sufficient to permit rapid catalysis. Hydrogen peroxide levels of approximately 1.8/M (6% w/w) were attained in 2-3 h with 2.8 microM enzyme, corresponding to a productivity of approximately 30 g peroxide/g enzyme. Optimal conditions (within equipment limitations) were 900 psi oxygen, 2.6M ethanol, at 4 degrees C. Similar levels of products were reached in the reactor using enzyme immobilized covalently on controlled pore glass and noncovalently on an anion exchange support. Recycle of covalently immobilized enzyme was not possible as a result of enzyme inactivation after a single run. Limited recycle of noncovalently immobilized enzyme was accomplished with substantial decreases in levels of product attainable on each cycle. PMID:18597282

Nelles, L P; Arnold, J A; Willman, D S

1990-10-20

245

Conceptual Design of Low-Temperature Hydrogen Production and High-Efficiency Nuclear Reactor Technology  

NASA Astrophysics Data System (ADS)

Hydrogen, a potential alternative energy source, is produced commercially by methane (or LPG) steam reforming, a process that requires high temperatures, which are produced by burning fossil fuels. However, as this process generates large amounts of CO2, replacement of the combustion heat source with a nuclear heat source for 773-1173K processes has been proposed in order to eliminate these CO2 emissions. In this paper, a novel method of nuclear hydrogen production by reforming dimethyl ether (DME) with steam at about 573K is proposed. From a thermodynamic equilibrium analysis of DME steam reforming, the authors identified conditions that provide high hydrogen production fraction at low pressure and temperatures of about 523-573K. By setting this low-temperature hydrogen production process upstream from a turbine and nuclear reactor at about 573K, the total energy utilization efficiency according to equilibrium mass and heat balance analysis is about 50%, and it is 75%for a fast breeder reactor (FBR), where turbine is upstream of the reformer.

Fukushima, Kimichika; Ogawa, Takashi

246

ACRR (Annular Core Research Reactor) fission product release tests: ST-1 and ST-2  

SciTech Connect

Two experiments (ST-1 and ST-2) have been performed in the Annular Core Research Reactor (ACER) at Sandia National Laboratories (SNLA) to obtain time-resolved data on the release of fission products from irradiated fuels under light water reactor (LWR) severe accident conditions. Both experiments were conducted in a highly reducing environment at maximum fuel temperatures of greater than 2400 K. These experiments were designed specifically to investigate the effect of increased total pressure on fission product release; ST-1 was performed at approximately 0.16 MPa and ST-2 was run at 1.9 MPa, whereas other parameters were matched as closely as possible. Release rate data were measured for Cs, I, Ba, Sr, Eu, Te, and U. The release rates were higher than predicted by existing codes for Ba, Sr, Eu, and U. Te release was very low, but Te did not appear to be sequestered by the zircaloy cladding; it was evenly distributed in the fuel. In addition, in posttest analysis a unique fuel morphology (fuel swelling) was observed which may have enhanced fission product release, especially in the high pressure test (ST-2). These data are compared with analytical results from the CORSOR correlation and the VICTORIA computer model. 8 refs., 8 figs., 2 tabs.

Allen, M.D.; Stockman, H.W.; Reil, K.O.; Grimley, A.J.; Camp, W.J.

1988-01-01

247

Analysis of fission product revaporization in a BWR Reactor Coolant System during a station blackout accident  

SciTech Connect

This paper presents an analysis of fission product revaporization from the Reactor Coolant System (RCS) following the Reactor Pressure Vessel (RPV) failure. The station blackout accident in a BWR Mark I Power Plant was considered. The TRAPMELT3 models for vaporization, chemisorption, and the decay heating of RCS structures and gases were used and extended beyond the RPV failure in the analysis. The RCS flow models based on the density-difference or pressure-difference between the RCS and containment pedestal region were developed to estimate the RCS outflow which carries the revaporized fission product to the containment. A computer code called REVAP was developed for the analysis. The REVAP code was incorporated with the MARCH, TRAPMELT3 and NAUA codes from the Source Term Code Package (STCP) to estimate the impact of revaporization on environmental release. The results show that the thermal-hydraulic conditions between the RCS and the pedestal region are important factors in determining the magnitude of revaporization and subsequent release of the volatile fission product into the environment. 6 refs., 8 figs.

Yang, J.W.; Schmidt, E.; Cazzoli, E.; Khatib-Rahbar, M.

1988-01-01

248

Very High Efficiency Reactor (VHER) Concepts for Electrical Power Generation and Hydrogen Production.  

National Technical Information Service (NTIS)

The goal of the Very High Efficiency Reactor study was to develop and analyze concepts for the next generation of nuclear power reactors. The next generation power reactor should be cost effective compared to current power generation plant, passively safe...

E. J. Parma P. S. Pickard A. J. Suo-Anttila

2003-01-01

249

Environmental characterization of two potential locations at Hanford for a new production reactor  

SciTech Connect

This report describes various environmental aspects of two areas on the Hanford Site that are potential locations for a New Production Reactor (NPR). The area known as the Skagit Hanford Site is considered the primary or reference site. The second area, termed the Firehouse Site, is considered the alternate site. The report encompasses an environmental characterization of these two potential NPR locations. Eight subject areas are covered: geography and demography; ecology; meteorology; hydrology; geology; cultural resources assessment; economic and social effects of station construction and operation; and environmental monitoring. 80 refs., 68 figs., 109 tabs.

Watson, E.C.; Becker, C.D.; Fitzner, R.E.; Gano, K.A.; Imhoff, K.L.; McCallum, R.F.; Myers, D.A.; Page, T.L.; Price, K.R.; Ramsdell, J.V.; Rice D.G.; Schreiber D.L.; Skumatz L.A.; Sommer D.J.; Tawil J.J.; Wallace R.W.; Watson D.G.

1984-09-01

250

Feasibility study for production of I-131 radioisotope using MNSR research reactor.  

PubMed

A feasibility study for (131)I production using a Low Power Research Reactor was conducted to predict the yield of (131)I by cyclic activation technique. A maximum activity of 5.1GBq was achieved through simulation using FORTRAN 90, for an irradiation of 6h. But experimentally only 4h irradiation could be done, which resulted in an activity of 4.0×10(5)Bq. The discrepancy in the activities was due to the fact that beta decays released during the process could not be considered. PMID:21900016

Elom Achoribo, A S; Akaho, Edward H K; Nyarko, Benjamin J B; Osae Shiloh, K D; Odame Duodu, Godfred; Gibrilla, Abass

2011-08-23

251

Fission Product Monitoring of TRISO Coated Fuel For The Advanced Gas Reactor -1 Experiment  

SciTech Connect

The US Department of Energy has embarked on a series of tests of TRISO-coated particle reactor fuel intended for use in the Very High Temperature Reactor (VHTR) as part of the Advanced Gas Reactor (AGR) program. The AGR-1 TRISO fuel experiment, currently underway, is the first in a series of eight fuel tests planned for irradiation in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The AGR-1 experiment reached a peak compact averaged burn up of 9% FIMA with no known TRISO fuel particle failures in March 2008. The burnup goal for the majority of the fuel compacts is to have a compact averaged burnup greater than 18% FIMA and a minimum compact averaged burnup of 14% FIMA. At the INL the TRISO fuel in the AGR-1 experiment is closely monitored while it is being irradiated in the ATR. The effluent monitoring system used for the AGR-1 fuel is the Fission Product Monitoring System (FPMS). The FPMS is a valuable tool that provides near real-time data indicative of the AGR-1 test fuel performance and incorporates both high-purity germanium (HPGe) gamma-ray spectrometers and sodium iodide [NaI(Tl)] scintillation detector-based gross radiation monitors. To quantify the fuel performance, release-to-birth ratios (R/B’s) of radioactive fission gases are computed. The gamma-ray spectra acquired by the AGR-1 FPMS are analyzed and used to determine the released activities of specific fission gases, while a dedicated detector provides near-real time count rate information. Isotopic build up and depletion calculations provide the associated isotopic birth rates. This paper highlights the features of the FPMS, encompassing the equipment, methods and measures that enable the calculation of the release-to-birth ratios. Some preliminary results from the AGR-1 experiment are also presented.

Dawn M. Scates; John (Jack) K Hartwell; John B. Walter

2008-09-01

252

Measurement of environmental radiation exposure rates from Vernita, Hanford Reach, and Richland area shores. Addendum 1  

SciTech Connect

Environmental radiation exposure rate measurements are taken on and around the Hanford Site for Pacific Northwest Laboratory`s Hanford Site Surface Environmental Surveillance Project. In 1992, environmental radiation exposure rate measurements were taken from shoreline and island areas ranging from Vernita, along the Hanford Reach, down to the Richland Pumphouse. Measurements were taken primarily at locations known or expected to have elevated exposure rates as determined by examination of aerial photographs depicting radiation exposure measurements. Results from the 1992 survey indicated radiation exposure rates taken from the Hanford Reach area were elevated in comparison to the measurements taken from the Vernita area with ranges of 8 to 28 {mu}R/hr and 4 to 11 {mu}R/hr, respectively. In January 1994, additional shoreline radiation exposure rate measurements were taken from the Vernita, Hanford Reach, and Richland areas to determine the relationship of radiation exposure rates along the Richland area shores when compared to Vernita and Hanford Reach area exposure rates (measurements along the Richland area were not collected during the 1992 survey). This report discusses the 1994 results and is an addendum to the report that discussed the 1992 survey. An analysis of variance indicated a significant location interaction at a p-value of 0.0014. To determine differences between paried locations a post-hoc comparison of location means was performed on log transformed data using the Scheff{acute e}`s F-test. This test indicated a significant difference between Hanford Reach and Richland area means with a mean difference of 0.075 /{mu}R/hr and a p-value of 0.0014. No significant difference was found between Hanford Reach and Vernita area means: The mean difference was 0.031 {mu}R/hr and the p-value was 0.3138. No significant difference was found between Vernita and Richland area means with a mean difference of 0.044 {mu}R/hr and a p-value of 0.1155.

Cooper, A.T.

1995-02-01

253

Integration of a turbine expander with an exothermic reactor loop—Flow sheet development and application to ammonia production  

Microsoft Academic Search

This paper investigates the direct integration of a gas turbine power cycle with an ammonia synthesis loop. Such a loop represents a typical reactor–separator system with a recycle stream and cold separation of the product from the recycle loop. The hot reaction products are expanded directly instead of raising steam in a waste heat boiler to drive a steam turbine.

I. L. Greeff; J. A. Visser; K. J. Ptasinski; F. J. J. G. Janssen

2003-01-01

254

Double-ended break probability estimate for the 304 stainless steel main circulation piping of a production reactor  

SciTech Connect

The large break frequency resulting from intergranular stress corrosion cracking in the main circulation piping of the Savannah River Site (SRS) production reactors has been estimated. Four factors are developed to describe the likelihood that a crack exists that is not identified by ultrasonic inspection, and that grows to instability prior to growing through-wall and being detected by the ensuing leakage. The estimated large break frequency is 3.4 {times} 10{sup {minus}8} per reactor-year.

Mehta, H.S. (General Electric Co., San Jose, CA (United States)); Daugherty, W.L.; Awadalla, N.G.; Sindelar, R.L. (Westinghouse Savannah River Co., Aiken, SC (United States))

1991-01-01

255

Fatty acids production from hydrogen and carbon dioxide by mixed culture in the membrane biofilm reactor.  

PubMed

Gasification of waste to syngas (H2/CO2) is seen as a promising route to a circular economy. Biological conversion of the gaseous compounds into a liquid fuel or chemical, preferably medium chain fatty acids (caproate and caprylate) is an attractive concept. This study for the first time demonstrated in-situ production of medium chain fatty acids from H2 and CO2 in a hollow-fiber membrane biofilm reactor by mixed microbial culture. The hydrogen was for 100% utilized within the biofilms attached on the outer surface of the hollow-fiber membrane. The obtained concentrations of acetate, butyrate, caproate and caprylate were 7.4, 1.8, 0.98 and 0.42 g/L, respectively. The biomass specific production rate of caproate (31.4 mmol-C/(L day g-biomass)) was similar to literature reports for suspended cell cultures while for caprylate the rate (19.1 mmol-C/(L day g-biomass)) was more than 6 times higher. Microbial community analysis showed the biofilms were dominated by Clostridium spp., such as Clostridium ljungdahlii and Clostridium kluyveri. This study demonstrates a potential technology for syngas fermentation in the hollow-fiber membrane biofilm reactors. PMID:23941982

Zhang, Fang; Ding, Jing; Zhang, Yan; Chen, Man; Ding, Zhao-Wei; van Loosdrecht, Mark C M; Zeng, Raymond J

2013-07-31

256

Letter report: Title listing of daily operating data on Hanford single-pass reactors, 1944--1971  

SciTech Connect

The primary objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that populations and individuals could have received as a result of emissions from Hanford Site operations since 1944, with descriptions of the uncertainties inherent in such estimates. A secondary objective is to make project documentation and Hanford-originated references used in the reports available to the public. Hanford-originated documents of potential interest and/or use to the HEDR Project are made publicly available through the US Government's National Technical Information Service and placed in the US Department of Energy Richland Field Office (RL) Public Reading Room in Richland, Washington. Project work is conducted under several technical tasks, among which is the Source Terms Task. Under this task, estimates of radioactive emissions from Hanford facilities since 1944 are developed. These estimates are based on historical measurements and production information. The Information Resources Task identifies and retrieves historical production operating information for developing source terms. The purpose of this letter report is to identify documents that record daily reactor operating information at the Hanford Site for the years 1944--1971. Complete bibliographic citations and sample pages from each different format for Hanford reactor operations data are included.

Gydesen, S.P.

1992-02-01

257

Hydrogen production and combustion in severe reactor accidents: an integral assessment perspective  

SciTech Connect

Hydrogen production and combustion during hypothetical severe nuclear reactor accidents are discussed from the perspective of integral predictive assessment of such accidents. Unmitigated hydrogen production after prolonged core dryout has the adverse impacts of accelerating the degradation of core geometry, reducing heat transfer area, and impeding the in-vessel recovery of an accident. Unmitigated hydrogen combustion can, in certain circumstances, lead to containment failure, or it could damage equipment and thereby impede recovery. The phenomena of in-vessel hydrogen generation and combustion are summarized, including recent experiments, and selected models for integral predictive assessment of these phenomena are described. Adequacies and shortcomings of models and the experimental data base are identified, and the effects of mitigation are discussed.

Plys, M.G. (Fauske and Assoc., Inc., Burr Ridge, IL (United States))

1993-03-01

258

Model of the control rod housing overflow incident in a Savannah River Production Reactor.  

National Technical Information Service (NTIS)

On May 25, 1992, K-reactor at the Savannah River Site was being configured for start up when a D20 leak of unknown origin was detected on the top of the reactor. The reactor was immediately shutdown, and reactor start up was put on hold until the cause of...

M. A. Shadday G. P. Flach J. L. Steimke L. D. Koffman N. M. Askew

1993-01-01

259

EVALUATION OF ACTIVATION PRODUCTS IN REMAINING IN REMAINING K-, L- AND C-REACTOR STRUCTURES  

SciTech Connect

An analytic model and calculational methodology was previously developed for P-reactor and R-reactor to quantify the radioisotopes present in Savannah River Site (SRS) reactor tanks and the surrounding structural materials as a result of neutron activation of the materials during reactor operation. That methodology has been extended to K-reactor, L-reactor, and C-reactor. The analysis was performed to provide a best-estimate source term input to the Performance Assessment for an in-situ disposition strategy by Site Decommissioning and Demolition (SDD). The reactor structure model developed earlier for the P-reactor and R-reactor analyses was also used for the K-reactor and L-reactor. The model was suitably modified to handle the larger Creactor tank and associated structures. For all reactors, the structure model consisted of 3 annular zones, homogenized by the amount of structural materials in the zone, and 5 horizontal layers. The curie content on an individual radioisotope basis and total basis for each of the regions was determined. A summary of these results are provided herein. The efficacy of this methodology to accurately predict the radioisotopic content of the reactor systems in question has been demonstrated and is documented in Reference 1. As noted in that report, results for one reactor facility cannot be directly extrapolated to other SRS reactors.

Vinson, D.; Webb, R.

2010-09-30

260

Studies of Plutonium-238 Production at the High Flux Isotope Reactor  

SciTech Connect

The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) is a versatile 85 MW{sub th}, pressurized, light water-cooled and -moderated research reactor. The core consists of two fuel elements, an inner fuel element (IFE) and an outer fuel element (OFE), each constructed of involute fuel plates containing high-enriched-uranium (HEU) fuel ({approx}93 wt% {sup 235}U/U) in the form of U{sub 3}O{sub 8} in an Al matrix and encapsulated in Al-6061 clad. An over-moderated flux trap is located in the center of the core, a large beryllium reflector is located on the outside of the core, and two control elements (CE) are located between the fuel and the reflector. The flux trap and reflector house numerous experimental facilities which are used for isotope production, material irradiation, and cold/thermal neutron scattering. Over the past five decades, the US Department of Energy (DOE) and its agencies have been producing radioisotope power systems used by the National Aeronautics and Space Administration (NASA) for unmanned, long-term space exploration missions. Plutonium-238 is used to power Radioisotope Thermoelectric Generators (RTG) because it has a very long half-life (t{sub 1/2} {approx} 89 yr.) and it generates about 0.5 watts/gram when it decays via alpha emission. Due to the recent shortage and uncertainty of future production, the DOE has proposed a plan to the US Congress to produce {sup 238}Pu by irradiating {sup 237}Np as early as in fiscal year 2011. An annual production rate of 1.5 to 2.0 kg of {sup 238}Pu is expected to satisfy these needs and could be produced in existing national nuclear facilities like HFIR and the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). Reactors at the Savannah River Site were used in the past for {sup 238}Pu production but were shut down after the last production in 1988. The nation's {sup 237}Np inventory is currently stored at INL. A plan for producing {sup 238}Pu at US research reactor facilities such as the High Flux Isotope Reactor at ORNL has been initiated by the US DOE and NASA for space exploration needs. Two Monte Carlo-based depletion codes, TRITON (ORNL) and VESTA (IRSN), were used to study the {sup 238}Pu production rates with varying target configurations in a typical HFIR fuel cycle. Preliminary studies have shown that approximately 11 grams and within 15 to 17 grams of {sup 238}Pu could be produced in the first irradiation cycle in one small and one large VXF facility, respectively, when irradiating fresh target arrays as those herein described. Important to note is that in this study we discovered that small differences in assumptions could affect the production rates of Pu-238 observed. The exact flux at a specific target location can have a significant impact upon production, so any differences in how the control elements are modeled as a function of exposure, will also cause differences in production rates. In fact, the surface plot of the large VXF target Pu-238 production shown in Figure 3 illustrates that the pins closest to the core can potentially have production rates as high as 3 times those of pins away from the core, thus implying that a cycle-to-cycle rotation of the targets may be well advised. A methodology for generating spatially-dependent, multi-group self-shielded cross sections and flux files with the KENO and CENTRM codes has been created so that standalone ORIGEN-S inputs can be quickly constructed to perform a variety of {sup 238}Pu production scenarios, i.e. combinations of the number of arrays loaded and the number of irradiation cycles. The studies herein shown with VESTA and TRITON/KENO will be used to benchmark the standalone ORIGEN.

Lastres, Oscar [University of Tennessee, Knoxville (UTK); Chandler, David [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Jarrell, Joshua J [ORNL; Maldonado, G. Ivan [University of Tennessee, Knoxville (UTK)

2011-01-01

261

Factors affecting cell growth and monoclonal antibody production in stirred reactors.  

PubMed

Environmental and cultural factors that could affect growth and cell viability of mouse-mouse hybridoma cells in culture were investigated. The aim was to determine conditions that could prolong viability and result in increased yields of monoclonal antibodies in stirred reactors. Factors studied included temperature, level of dissolved oxygen, nutrient depletion, and waste product accumulation. Growing cells at temperatures 3-9 degrees lower than optimum (37 degrees C) increased viability but monoclonal antibody production was lowered. A low level of dissolved oxygen (25% air saturation compared to 60% for optimum growth) prolonged cell viability and increased the monoclonal antibody yield by about 50%. Feeding cultures daily to maintain the glucose level above 1 mg/ml and at the same time feeding cells glutamine (150 micrograms/10(6) cells per day) maintained the level of viable cells at 1.7 X 10(6)/ml for at least 9 days and resulted in an antibody yield of 290 micrograms/ml, about a 70% increase over cultures fed either glucose or glutamine alone. Ammonium ion, added to cell populations at levels produced in cultures, stopped cell growth and decreased antibody production. Another waste product, lactic acid, had no toxic effect when added to media at levels found in cultures. These results agree with our suggestion that monoclonal antibody production is enhanced by maintaining cell viability over a prolonged period and provide a base for investigating modes of hybridoma cell propagation in fermentors. PMID:3944469

Reuveny, S; Velez, D; Macmillan, J D; Miller, L

1986-01-22

262

Gasification of refuse derived fuel in a fixed bed reactor for syngas production  

SciTech Connect

Steam gasification of two different refuse derived fuels (RDFs), differing slightly in composition as well as thermal stability, was carried out in a fixed-bed reactor at atmospheric pressure. The proximate and ultimate analyses reveal that carbon and hydrogen are the major components in RDFs. The thermal analysis indicates the presence of cellulose and plastic based materials in RDFs. H{sub 2} and CO are found to be the major products, along with CO{sub 2} and hydrocarbons resulting from gasification of RDFs. The effect of gasification temperature on H{sub 2} and CO selectivities was studied, and the optimum temperature for better H{sub 2} and CO selectivity was determined to be 725 deg. C. The calorific value of product gas produced at lower gasification temperature is significantly higher than that of gas produced at higher process temperature. Also, the composition of RDF plays an important role in distribution of products gas. The RDF with more C and H content is found to produce more amounts of CO and H{sub 2} under similar experimental conditions. The steam/waste ratio showed a notable effect on the selectivity of syngas as well as calorific value of the resulting product gas. The flow rate of carrier gas did not show any significant effect on products yield or their distribution.

Dalai, Ajay K. [Catalysis and Chemical Reaction Engineering Laboratories, Department of Chemical Engineering, University of Saskatchewan, Saskatoon, SK, S7N 5A9 (Canada)], E-mail: ajay.dalai@usask.ca; Batta, Nishant [Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK, S7N 5A9 (Canada); Eswaramoorthi, I. [Catalysis and Chemical Reaction Engineering Laboratories, Department of Chemical Engineering, University of Saskatchewan, Saskatoon, SK, S7N 5A9 (Canada); Schoenau, Greg J. [Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK, S7N 5A9 (Canada)

2009-01-15

263

Radioactivity levels of the Columbia River below Richland, Washington for the period January, February, March 1955  

Microsoft Academic Search

The radioactivity levels of Columbia River water and mud are summarized for the area below Richland, Washington. Below the Kennewick Highland-Pasco section there is a gradual decrease in the activity density of beta particle emitters. The activity density of alpha particle emitters in Columbia River water averages 6.0 x 10⁻⁹ ..mu..c\\/ml at Kennewick Highlands and less than 5 x 10⁻⁹

Rostenbach

1955-01-01

264

Environmental Assessment Use of Existing Borrow Areas, Hanford Site, Richland, Washington  

SciTech Connect

The U.S. Department of Energy (DOE) operates the Hanford Site near Richland, Washington. The DOE needs to identify and operate onsite locations for a continued supply of raw aggregate materials [approximately 7,600,000 cubic meters (10,000,000 cubic yards) over the next 10 years] for new facility construction, maintenance of existing facilities and transportation corridors, and fill and capping material for remediation and other sites.

N /A

2001-10-10

265

Anaerobic baffled reactor treatment of biodiesel-processing wastewater with high strength of methanol and glycerol: reactor performance and biogas production  

Microsoft Academic Search

Biodiesel-processing factories employing the alkali-catalyzed transesterification process generate a large amount of wastewater\\u000a containing high amount of methanol, glycerol, and oil. As such, wastewater has high potential to produce biogas using anaerobic\\u000a treatment. The aim of this research was to investigate the performance of an anaerobic baffled reactor for organic removal\\u000a and biogas production from biodiesel wastewater. The effect of

Darin Phukingngam; Orathai Chavalparit; Dararat Somchai; Maneerat Ongwandee

2011-01-01

266

Three-dimensional nodal diffusion and transport methods for the analysis of fast-reactor critical experiments  

SciTech Connect

This paper describes two new nodal methods for solving the multigroup neutron diffusion and transport equations in three-dimensional Cartesian geometry. These methods have been developed for the global analysis of fast-reactor critical experiments once cell-averaged multigroup cross sections for each matrix position or drawer have been computed using appropriate cell-homogenization procedures. Brief descriptions of the nodal diffusion and transport schemes are presented, along with results of two- and three-dimensional calculations for a current Zero Power Plutonium Reactor (ZPPR) configuration.

Lawrence, R.D.

1984-01-01

267

Design and construction of a 7,500 liter immobilized cell reactor-separator for ethanol production from whey  

SciTech Connect

A 7,500 liter reactor/separator has been constructed for the production of ethanol from concentrated whey permeate. This unit is sited in Hopkinton IA, across the street from a whey generating cheese plant A two phase construction project consisting of (1) building and testing a reactor/separator with a solvent absorber in a single unified housing, and (2) building and testing an extractive distillation/product stripper for the recovery of anhydrous ethanol is under way. The design capacity of this unit is 250,000 gal/yr of anhydrous product. Design and construction details of the reactor/absorber separator are given, and design parameters for the extractive distillation system are described.

Dale, M.C.

1992-12-31

268

Fission Product Monitoring and Release Data for the Advanced Gas Reactor -1 Experiment  

SciTech Connect

The AGR-1 experiment is a fueled multiple-capsule irradiation experiment that was irradiated in the Advanced Test Reactor (ATR) from December 26, 2006 until November 6, 2009 in support of the Very High Temperature Reactor (VHTR) Technology Development Office (TDO) Fuel Development and Qualification program. An important measure of the fuel performance is the quantification of the fission product releases over the duration of the experiment. To provide this data for the inert fission gasses(Kr and Xe), a fission product monitoring system (FPMS) was developed and implemented to monitor the individual capsule effluents for the radioactive species. The FPMS continuously measured the concentrations of various krypton and xenon isotopes in the sweep gas from each AGR-1 capsule to provide an indicator of fuel irradiation performance. Spectrometer systems quantified the concentrations of Kr-85m, Kr-87, Kr-88, Kr-89, Kr-90, Xe-131m, Xe-133, Xe 135, Xe 135m, Xe-137, Xe-138, and Xe-139 accumulated over repeated eight hour counting intervals.-. To determine initial fuel quality and fuel performance, release activity for each isotope of interest was derived from FPMS measurements and paired with a calculation of the corresponding isotopic production or birthrate. The release activities and birthrates were combined to determine Release-to-Birth ratios for the selected nuclides. R/B values provide indicators of initial fuel quality and fuel performance during irradiation. This paper presents a brief summary of the FPMS, the release to birth ratio data for the AGR-1 experiment and preliminary comparisons of AGR-1 experimental fuels data to fission gas release models.

Dawn M. Scates; John B. Walter; Jason M. Harp; Mark W. Drigert; Edward L. Reber

2010-10-01

269

Rotating algal biofilm reactor and spool harvester for wastewater treatment with biofuels by-products.  

PubMed

Maximizing algae production in a wastewater treatment process can aid in the reduction of soluble nitrogen and phosphorus concentrations in the wastewater. If harvested, the algae-based biomass offers the added benefit as feedstock for the production of biofuels and bioproducts. However, difficulties in harvesting, concentrating, and dewatering the algae-based biomass have limited the development of an economically feasible treatment and production process. When algae-based biomass is grown as a surface attached biofilm as opposed to a suspended culture, the biomass is naturally concentrated and more easily harvested. This can lead to less expensive removal of the biomass from wastewater, and less expensive downstream processing in the production of biofuels and bioproducts. In this study, a novel rotating algal biofilm reactor (RABR) was designed, built, and tested at bench (8 L), medium (535 L), and pilot (8,000 L) scales. The RABR was designed to operate in the photoautotrophic conditions of open tertiary wastewater treatment, producing mixed culture biofilms made up of algae and bacteria. Growth substrata were evaluated for attachment and biofilm formation, and an effective substratum was discovered. The RABR achieved effective nutrient reduction, with average removal rates of 2.1 and 14.1 g m(-2) day(-1) for total dissolved phosphorus and total dissolved nitrogen, respectively. Biomass production ranged from 5.5 g m(-2) day(-1) at bench scale to as high as 31 g m(-2) day(-1) at pilot scale. An efficient spool harvesting technique was also developed at bench and medium scales to obtain a concentrated product (12-16% solids) suitable for further processing in the production of biofuels and bioproducts. PMID:22328283

Christenson, Logan B; Sims, Ronald C

2012-02-13

270

ENHANCED HYDROGEN PRODUCTION INTEGRATED WITH CO2 SEPARATION IN A SINGLE-STAGE REACTOR  

SciTech Connect

Hydrogen production by the water gas shift reaction (WGSR) is equilibrium limited due to thermodynamic constrains. However, this can be overcome by continuously removing the product CO{sub 2}, thereby driving the WGSR in the forward direction to enhance hydrogen production. This project aims at using a high reactivity, mesoporous calcium based sorbent (PCC-CaO) for removing CO{sub 2} using reactive separation scheme. Preliminary results have shown that PCC-CaO dominates in its performance over naturally occurring limestone towards enhanced hydrogen production. However, maintenance of high reactivity of the sorbent over several reaction-regeneration cycles warrants effective regeneration methods. We have identified sub-atmospheric calcination (vacuum) as vital regeneration technique that helps preserve the sorbent morphology. Sub-atmospheric calcination studies reveal the significance of vacuum level, diluent gas flow rate, thermal properties of diluent gas, and sorbent loading on the kinetics of calcination and the morphology of the resultant CaO sorbent. Steam, which can be easily separated from CO{sub 2}, has been envisioned as a potential diluent gas due to its better thermal properties resulting in effective heat transfer. A novel multi-fixed bed reactor was designed which isolates the catalyst bed from the sorbent bed during the calcination step. This should prevent any potential catalyst deactivation due to oxidation by CO{sub 2} during the regeneration phase.

Himanshu Gupta; Mahesh Iyer; Bartev Sakadjian; Liang-Shih Fan

2005-04-01

271

Two stage anaerobic baffled reactors for bio-hydrogen production from municipal food waste.  

PubMed

A two-step anaerobic baffled reactor (ABR-1 and ABR-2) for H2 production from municipal food waste (MFW) was investigated at a temperature of 26 °C. In ABR-1, the average yield of H2 at an HRT of 26 h and OLR of 58 kg COD/m3 d was 250 ml H2/g VS removed. As unexpected; the H2 production in the ABR-2 was further increased up to 370 ml H2/gVS removed at a HRT of 26 h and OLR of 35 kg COD/m3 d. The total H2 yield in the two-step process was estimated to be 4.9 mol H2/mol hexose. The major part of H2 production in the ABR-1 was due to the conversion of COD(particulate) (36%). In the ABR-2 the H2 yield was mainly due to the conversion of COD in the soluble form (76%). Based on these results MFW could be ideal substrate for H2 production in a two-step ABR processes. PMID:21498075

Tawfik, A; Salem, A; El-Qelish, M

2011-03-14

272

Continuous ethanol production by immobilized yeast reactor coupled with membrane pervaporation unit.  

PubMed

A system comprised of an immobilized yeast reactor producing ethanol, with a membrane pervaporation module for continuously removing and concentrating the produced ethanol, was developed. The combined system consisted of two integrated circulation loops: In one the sugar-containing medium is circulated through the membrane pervaporation module. The two loops were interconnected in a way allowing for separate parameter optimization (e.g., flow rate, temperature, pH) for each loop.The fermentation unit was 2.0 L bioreactor with five equal segments, packed with 5-mm beads of immobilized yeasts. The bead matrix was a crosslinked polyacrylamide hydrazide gel coated with calcium alginate. The fast circulation loop of the bioreactor allowed for efficient liberation of CO(2) at the top of the immobilized yeast reactor. Continuous operation of the uncoupled reactor for over 50 days with inflowing defined medium or dilute molasses at a residence time of 1.25 h yielded ethanol at a rate of about 10 g/L h.The pervaporation unit was constructed from four 60-cm-long tubular membranes of silicone composite on a polysulfone support. The output from the fermentor was circulated through the inside of the tubes of a unit with a total surface area of 800 cm(2), having an average flux of 150 mL/h, and selectivities to ethanol vs. water up to 7. A vacuum of 30 mb was applied to the outside of the tubes, removing 20-30 g of ethanol per hour, which was collected in condensors. The continuous removal of ethanol, avoiding inhibition of the fermentation process, resulted in an improved productivity and allowed the use of high sugar concentrations (40% wt/vol) offering the potential of a compact system with reduced stillage.The combined system of ethanol production and removal enabled an operative steady state at which the liquid volume of the system, and the concentrations of ethanol within the reactor ( 4% wt/vol), as well as within the flux crossing the pervaporation membrane (17%-20% wt/vol) were kept constant. At the steady state, a 40% wt/vol sugar solution could be continuously added to the fermentor when 12%-20% wt/vol clear ethanol solution was continuously removed by the pervaporation unit. Membrane fouling was reversed by short washing steps, and continuous step operation was maintained by working with two different modules that were interchanged. In this manner, long term continuous operation (over 40 days) was achieved with a productivity of 20-30 g/L h, representing over a twofold increase relative to the continuously operated reactor uncoupled from the membrane and a fivefold increase in comparison with the value obtained fro a corresponding batch fermentation. PMID:18600843

Shabtai, Y; Chaimovitz, S; Freeman, A; Katchalski-Katzir, E; Linder, C; Nemas, M; Perry, M; Kedem, O

1991-10-20

273

76 FR 37888 - Yellowstone Valley Railroad, L.L.C.-Discontinuance of Service Exemption-in Dawson and Richland...  

Federal Register 2010, 2011, 2012, 2013

...Transportation Board [Docket No. AB 991X] Yellowstone Valley Railroad, L.L.C.--Discontinuance...Dawson and Richland Counties, Mont. Yellowstone Valley Railroad, L.L.C. (YVRR...1\\ Applicant's name was formerly Yellowstone Valley Railroad, Inc. See Watco...

2011-06-28

274

A Report on the Mitigation of Impacts Upon the Beckwith Mound Group (47RI20) Gotham, Richland County, Wisconsin.  

National Technical Information Service (NTIS)

This report summarizes past and present day archeological investigations conducted on the abandoned townsite of Richland City, Wisconsin (ca. 1849-1920). This village was platted on top of several prehistoric mound, village and workshop sites at the mouth...

A. R. Woolworth N. L. Woolworth

1980-01-01

275

Geologic setting of the New Production Reactor within the Savannah River Site  

SciTech Connect

The geology and hydrology of the reference New Production Reactor (NPR) site at Savannah River Site (SRS) have been summarized using the available information from the NPR site and areas adjacent to the site, particularly the away from reactor spent fuel storage site (AFR site). Lithologic and geophysical logs from wells drilled near the NPR site do not indicate any faults in the upper several hundred feet of the Coastal Plain sediments. However, the Pen Branch Fault is located about 1 mile south of the site and extends into the upper 100 ft of the Coastal Plain sequence. Subsurface voids, resulting from the dissolution of calcareous portions of the sediments, may be present within 200 ft of the surface at the NPR site. The water table is located within 30 to 70 ft of the surface. The NPR site is located on a groundwater divide, and groundwater flow for the shallowest hydraulic zones is predominantly toward local streams. Groundwater flow in deeper Tertiary sediments is north to Upper Three Runs Creek or west to the Savannah River Swamp. Groundwater flow in the Cretaceous sediments is west to the Savannah River.

Price, V. [Westinghouse Savannah River Co., Aiken, SC (United States); Fallaw, W.C. [Furman Univ., Greenville, SC (United States). Dept. of Geology; McKinney, J.B. [Exploration Resources, Inc., Athens, GA (United States)

1991-12-31

276

Modification of PROMETHEUS Reactor as a Fusion Breeder and Fission Product Transmuter  

NASA Astrophysics Data System (ADS)

This study presents the analyses of the fissile breeding and long-lived fission product (LLFP) transmutation potentials of PROMETHEUS reactor. For this purpose, a fissile breeding zone (FBZ) fueled with the ceramic uranium mono-carbide (UC) and a LLFP transmutation zone (TZ) containing the 99TC and 129I and 135Cs isotopes are separately placed into the breeder zone of PROMETHEUS-H design. The neutronic calculations are performed by using two different computer codes, the XSDRNPM/SCALE4.4a neutron transport code and the MCNP4B Monte Carlo code. A range of analyses are examined to determine the effects of the FF, the fraction of 6Li in lithium (Li) and the theoretical density (TD) of Li2O in the tritium breeder zone (TBZ) on the neutronic parameters. It is observed that the numerical results obtained from both codes are consistent with each other. It is carried out that the profiles of fission power density (FPD) are flattened individually for each FF (from 3 to 10%). Only, in the cases of FF ? 8%, the system is self sufficient from the point of view of tritium generation. The results bring out that the modified PROMETHEUS fusion reactor has capabilities of effective fissile breeding and LLFP transmutation, as well as the energy generation.

Yap?c?, Hüseyin; Öz???k, Gül?ah

2008-12-01

277

Understanding the role of defect production in radiation embrittlement of reactor pressure vessels.  

SciTech Connect

Comparative experiments using high energy (10 MeV) electrons and test reactor neutrons have been undertaken to understand the role that primary damage state has on hardening (embrittlement) induced by irradiation at 300 C. Electrons produce displacement damage primarily by low energy atomic recoils, while fast neutrons produce displacements from considerably higher energy recoils. Comparison of changes resulting from neutron irradiation, in which nascent point defect clusters can form in dense cascades, with electron irradiation, where cascade formation is minimized, can provide insight into the role that the in-cascade point defect clusters have on the mechanisms of embrittlement. Tensile property changes induced by 10 MeV electrons or test reactor neutron irradiations of unalloyed iron and an Fe-0.9 wt.% Cu-1.0 wt.% Mn alloy were examined in the damage range of 9.0 x 10{sup {minus}5} dpa to 1.5 x 10{sup {minus}2} dpa. The results to date showed the ternary alloy experienced substantially greater embrittlement in both the electron and neutron irradiated samples relative to unalloyed iron. Surprisingly, despite their disparate nature of defect production, similar embrittlement trends with increasing radiation damage were observed for electrons and neutrons in both the ternary and unalloyed iron.

Alexander, D. E.

1999-08-04

278

A1-U fuel foaming/recriticality considerations for production reactor core-melt accidents  

SciTech Connect

Severe accident studies for the Savannah River production reactors indicate that if coherent fuel melting and relocation occur in the absence of target melting, in-vessel recriticality may be achieved. In this paper, fuel-melt/target interaction potential is assessed, where fission gas-induced fuel foaming and melt attach on target material are evaluated and compared with available data. Models are developed to characterize foams for irradiated Al-based fuel. Predictions indicate transient foaming (the extent of which is governed by fission gas inventory), heating transient, and bubble coalescence behavior. The model also indicates that metallic foams are basically unstable and will collapse, which largely depends on film tenacity and melt viscosity. For high-burnup fuel, foams lasting tens of seconds are predicted, allowing molten fuel to contact and cause melt ablation of concentric targets. For low-burnup fuel, contact can not be assured, thus recriticality may be of concern at reactor startup. 8 refs., 4 figs., 4 tabs.

Cronenberg, A.W. (Engineering Science and Analysis, Albuquerque, NM (USA)); Hyder, M.L.; Ellison, P.G. (Westinghouse Savannah River Co., Aiken, SC (USA))

1990-01-01

279

Evaluation of radcal gamma thermometers for in-core monitoring of Savannah River Site production reactors  

SciTech Connect

The Savannah River Site (SRS) recently obtained a quantity of Radcal Gamma Thermometer Assemblies (RGTAs) for in-core monitoring of local power in their production reactors. The RGTAs, manufactured by DELTA M Corporation in Oak Ridge, Tennessee, contained seven Self Calibrating Gamma Thermometer (SCGT) sensors within a 7.26 mm diameter, 3.06 m length with a total length of 5.6 m. All RGTAs contained an isolated segmented heater cable for in-situ calibration. Each SCGT sensor was subjected to a 40 point calibration at discrete power levels from 0.5 to 6 watts per gram (w/g) under both joule and cable power. Calibration equations were developed from this to predict reactor power at each sensor. Additionally three units were calibrated at combined joule and cable heating conditions from 0.5 to 2.5 w/g cable and 0.5 to 6 w/g joule. A statistical analysis of all data was used to derive prediction equations that enable SRS engineers to precisely track any changes in sensor calibration throughout the lifetime of the instruments. This paper presents the detailed configuration of the 36 units manufactured for SRS, reviews the calibration results, and discusses the utility and accuracy of the statistically derived prediction equations for in-situ calibration.

McCulloch, R.W.; Crowley, J.L. [DELTA M Corp., Oak Ridge, TN (United States); Croft, W.D. [Westinghouse Savannah River Co., Aiken, SC (United States)

1991-12-31

280

Evaluation of radcal gamma thermometers for in-core monitoring of Savannah River Site production reactors  

SciTech Connect

The Savannah River Site (SRS) recently obtained a quantity of Radcal Gamma Thermometer Assemblies (RGTAs) for in-core monitoring of local power in their production reactors. The RGTAs, manufactured by DELTA M Corporation in Oak Ridge, Tennessee, contained seven Self Calibrating Gamma Thermometer (SCGT) sensors within a 7.26 mm diameter, 3.06 m length with a total length of 5.6 m. All RGTAs contained an isolated segmented heater cable for in-situ calibration. Each SCGT sensor was subjected to a 40 point calibration at discrete power levels from 0.5 to 6 watts per gram (w/g) under both joule and cable power. Calibration equations were developed from this to predict reactor power at each sensor. Additionally three units were calibrated at combined joule and cable heating conditions from 0.5 to 2.5 w/g cable and 0.5 to 6 w/g joule. A statistical analysis of all data was used to derive prediction equations that enable SRS engineers to precisely track any changes in sensor calibration throughout the lifetime of the instruments. This paper presents the detailed configuration of the 36 units manufactured for SRS, reviews the calibration results, and discusses the utility and accuracy of the statistically derived prediction equations for in-situ calibration.

McCulloch, R.W.; Crowley, J.L. (DELTA M Corp., Oak Ridge, TN (United States)); Croft, W.D. (Westinghouse Savannah River Co., Aiken, SC (United States))

1991-01-01

281

Effect of fermented wastewaters from butter production on phosphates removal in a sequencing batch reactor.  

PubMed

This study determined the potential for fermented wastewaters from butter production plant to act as a carbon source to facilitate phosphates removal. Synthetic dairy wastewaters were treated using SBR, with doses of fermented wastewaters. An increase in the fermented wastewater doses were found to improve the effluent quality in respect of phosphates and nitrates. The lowest concentrations of phosphate and nitrates, respectively 0.10 ± 0.04 mg PO(4)-PL(-1) and 1.03 ± 0.22 mg NO(3)-NL(-1), were noted in the effluent from the reactor fed with fermented wastewaters in a dose of 0.25 L d(-1) per 0.45 L d(-1) of wastewaters fed to the reactor. In the case of the two highest doses, an increase in effluent COD was stated. The higher effectiveness resulted from the fact that the introduction of fermented wastewaters caused an increase in the easily-available carbon compounds content and the predominance of acetic acid amongst VFAs available to dephosphatating and denitrifying bacteria. PMID:22776262

Janczukowicz, Wojciech; Rodziewicz, Joanna; Thornton, Arthur; Czaplicka, Kamila

2012-06-19

282

[Interview]: Alexandre Shvartsburg, Pacific Northwest National Laboratory, Richland, WA, USA  

SciTech Connect

Q1. What are your main research activities in ion mobility mass spectrometry (past or present)? My early efforts focused on the structural characterization of atomic (carbon and semiconductor) clusters. After the production of bulk fullerenes, many hoped that other nanoclusters discovered in the gas phase could also coalesce into new materials. As these studies required accurate and robust mobility calculations for any ion geometry, I strived to build the needed theory and implement it in the Mobcal software widely employed today. Since 2004, I have been developing methods and novel applications of differential IMS (FAIMS) at PNNL. The principal achievement has been raising the resolving power by over tenfold (up to ~400 for multiply-charged peptides) using elevated fields, helium and hydrogen-rich buffers, and extended filtering times. This performance broadly allows previously unthinkable separations of very similar species, for example sequence inversions and post-translational modification localization isomers of peptides (including “middle-down” peptides such as histone tails), lipid regioisomers, and even isotopomers. Another major direction is investigating the dipole alignment of larger proteins, which creates an exceptionally strong FAIMS effect that is a potential tool for structural biology. Q2: What have been the most significant instrumentation or applications developments in the history of ion mobility - mass spectrometry? In 1995 when I started graduate research at Northwestern, only two groups worldwide worked with IMS/MS and “the literature” meant papers by Bowers (UCSB). Well-wishers counseled me to “learn something useful like HPLC, as IMS would never have real utility”. This booklet showcases the scale of change since. First, the practical IMS/ToF platforms for complex biological analyses demonstrated by Clemmer have turned IMS/MS from an esoteric physical chemistry technique into a powerful analytical tool. By commercializing the IMS/ToF technology in Synapt instruments, Waters has greatly increased its impact via expanded number and diversity of applications. Concurrently, Guevremont at Canadian NRC has perfected FAIMS coupled to MS, deployed it for real-world bio and environmental analyses, and widely distributed it in the Ionalytics Selectra system (subsequently installed on Thermo MS platforms). The latest breakthrough is ultra-FAIMS by Owlstone, where extreme fields allow numerous qualitatively new separations and operational modes that we just begin to explore. Q3: Where do you see ion mobility - mass spectrometry making the most impact in the next 5 years? Any predictions for where the field will go? Sciences dealing with perturbations in media (such as optics or acoustics) at some point shift from the linear to nonlinear paradigm, where propagation depends on the magnitude of perturbation or its driving force. While the linear part remains industrially important (e.g., eyewear and architectural glass for optics), frontline research moves to nonlinear phenomena. IMS is undergoing that transition now with the rise of FAIMS, which should continue as the fundamental understanding improves, new modalities and applications emerge, and more instrumentation is introduced by vendors. Modifying and augmenting FAIMS separations through vapor dopants that render ion mobilities less linear is becoming routine. I expect this area to advance, extending to more specific interactions and to complexation with solution additives. Another route to higher separation power is integrating FAIMS with conventional IMS; proliferation of both technologies would make such 2-D platforms common. Along with mass spectrometry and conventional IMS, FAIMS will address increasingly large macromolecules, including proteins and their complexes.

Shvartsburg, Alexandre A.

2012-12-01

283

Aluminum/uranium fuel foaming/recriticality considerations for production reactor core-melt accidents  

SciTech Connect

Severe accident studies for the Savannah River production reactors indicate that if coherent fuel melting and relocation occur in the absence of target melting, in-vessel recriticality may be achieved. In this paper, fuel-melt/target interaction potential is assessed where fission gas-induced fuel foaming and melt attack on target material are evaluated and compared with available data. Models are developed to characterize foams for irradiated aluminum-based fuel. Predictions indicate transient foaming, the extent of which is governed by fission gas inventory, heating transient conditions, and bubble coalescence behavior. The model also indicates that metallic foams are basically unstable and will collapse, which largely depends on film tenacity and melt viscosity considerations. For high-burnup fuel, extensive foaming lasting tens of seconds is predicted, allowing molten fuel to contact and cause melt ablation of concentric targets. For low-burnup fuel, contact can not be assured. 9 refs., 4 figs., 4 tabs.

Hyder, M.L.; Ellison, P.G. (Westinghouse Savannah River Co., Aiken, SC (USA)); Cronenberg, A.W. (Engineering Science and Analysis, Albuquerque, NM (USA))

1990-01-01

284

Analysis of the magnetic corrosion product deposits on a boiling water reactor cladding  

NASA Astrophysics Data System (ADS)

The buildup of corrosion product deposits (CRUD) on the fuel cladding of the boiling water reactor (BWR) before and after zinc injection has been investigated by applying local experimental analytical techniques. Under the BWR water chemistry conditions, Zn addition together with the presence of Ni and Mn induce the formation of (Zn,Ni,Mn)[Fe2O4] spinel solid solutions. X-ray absorption spectroscopy (XAS) revealed inversion ratios of cation distribution in spinels deposited from the solid solution. Based on this information, a two-site ferrite spinel solid solution model is proposed. Electron probe microanalysis (EPMA) and extended X-ray absorption fine structure (EXAFS) findings suggest the zinc-rich ferrite spinels formation on BWR fuel cladding mainly at lower pin.

Orlov, Andrey; Degueldre, Claude; Kaufmann, Wilfried

2013-01-01

285

Production of Sn-117m in the BR2 and HFIR High-Flux Reactors  

SciTech Connect

Tin-117m (T 14.0 d; 159 keV, 86%) is a promising radionuclide for therapeutic applications. In contrast to beta emitters, 117mSn emits low-energy conver-sion electrons that deposit their intense energy (127, 129, 152 keV) within a short range (0.22 - 0.29 mm) which can destroy tumors but not damage the bone marrow or other healthy tissues. The 159 keV gamma photons are ideal for imaging to monitor the cancer. This paper reports the results of 117mSn production yield calculations and measurements for several irradiation conditions which can be achieved in both the BR2 (Mol, Belgium) and HFIR (Oak Ridge, USA) High-Flux research reactors.

Ponsard, Bernard [Belgian Nuclear Research Centre, SCK-CEN; Garland, Marc A [ORNL; Knapp Jr, Russ F [ORNL; Mirzadeh, Saed [ORNL; Srivastava, Suresh [Brookhaven National Laboratory (BNL); Mausner, Leonard [Brookhaven National Laboratory (BNL)

2008-01-01

286

Consequences of tritium release to water pathways from postulated accidents in a DOE production reactor  

SciTech Connect

A full-scale PRA of a DOE production reactor has been completed that considers full release of tritium as part of the severe accident source term. Two classes of postulated reactor accidents, a loss-of-moderator pumping accident and a loss-of-coolant accident, are used to bound the expected dose consequence from liquid pathway release. Population doses from the radiological release associated with the two accidents are compared for aqueous discharge and atmospheric release modes. The expectation values of the distribution of possible values for the societal effective dose equivalent to the general public, given a tritium release to the atmosphere, is 2.8 person-Sv/PBq (9.9 {times} 10{sup {minus}3} person-rem/Ci). The general public drinking water dose to downstream water consumers is 6.5 {times} 10{sup {minus}2} person-Sv/Pbq (2.4 {times} 10{sup {minus}4} person-rem/Ci) for aqueous releases to the surface streams eventually reaching the Savannah River. Negligible doses are calculated for freshwater fish and saltwater invertebrate consumption, irrigation, and recreational use of the river, given that an aqueous release is assumed to occur. Relative to the balance of fission products released in a hypothetical severe accident, the tritium-related dose is small. This study suggests that application of regional models (1610 km radius) will indicate larger dose consequences from short-term tritium release to the atmosphere than from comparable tritium source terms to water pathways. However, the water pathways assessment is clearly site-specific, and the overall aqueous dose will be dependent on downstream receptor populations and uses of the river.

O`Kula, K.R.; Olson, R.L.; Hamby, D.M.

1991-12-31

287

Analysis of fission product revaporization in a BWR reactor cooling system during a station blackout accident  

SciTech Connect

This report presents a preliminary analysis of fission product revaporization in the Reactor Cooling System (RCS) after the vessel failure. The station blackout transient for BWR Mark I Power Plant is considered. The TRAPMELT3 models of evaporization, chemisorption, and the decay heating of RCS structures and gases are adopted in the analysis. The RCS flow models based on the density-difference between the RCS and containment pedestal region are developed to estimate the RCS outflow which carries the revaporized fission product to the containment. A computer code called REVAP is developed for the analysis. The REVAP is incorporated with the MARCH, TRAPMELT3 and NAUA codes of the Source Term Code Pack Package (STCP). The NAUA code is used to estimate the impact of revaporization on environmental release. The results show that the thermal-hydraulic conditions between the RCS and the pedestal region are important factors determining the magnitude of revaporization and subsequent release of the volatile fission product. 8 figs., 1 tab.

Yang, J.W.; Schmidt, E.; Cazzoli, E.; Khatib-Rahbar, M.

1988-01-01

288

Part I. Fuel-motion diagnostics in support of fast-reactor safety experiments. Part II. Fission product detection system in support of fast reactor safety experiments  

SciTech Connect

In all destructive fast-reactor safety experiments at TREAT, fuel motion and cladding failure have been monitored by the fast-neutron/gamma-ray hodoscope, providing experimental results that are directly applicable to design, modeling, and validation in fast-reactor safety. Hodoscope contributions to the safety program can be considered to fall into several groupings: pre-failure fuel motion, cladding failure, post-failure fuel motion, steel blockages, pretest and posttest radiography, axial-power-profile variations, and power-coupling monitoring. High-quality results in fuel motion have been achieved, and motion sequences have been reconstructed in qualitative and quantitative visual forms. A collimated detection system has been used to observe fission products in the upper regions of a test loop in the TREAT reactor. Particular regions of the loop are targeted through any of five channels in a rotatable assembly in a horizontal hole through the biological shield. A well-type neutron detector, optimized for delayed neutrons, and two GeLi gamma ray spectrometers have been used in several experiments. Data are presented showing a time history of the transport of Dn emitters, of gamma spectra identifying volatile fission products deposited as aerosols, and of fission gas isotopes released from the coolant.

Devolpi, A.; Doerner, R.C.; Fink, C.L.; Regis, J.P.; Rhodes, E.A.; Stanford, G.S.; Braid, T.H.; Boyar, R.E.

1986-05-01

289

Benefit of sodium hydroxide pretreatment of ensiled sorghum forage on the anaerobic reactor stability and methane production.  

PubMed

The assessment of the pretreatment effect on the anaerobic digestion process is generally based on the results of batch tests, which may fail in truly predicting full-scale anaerobic reactors performance. Therefore, in this study, the effect of alkaline pretreatment on the anaerobic digestion of ensiled sorghum forage was evaluated by comparing the results of two semi-continuous CSTR (Continuously Stirred Tank Reactor) anaerobic reactors. Results showed that an alkaline pretreatment step, prior to the anaerobic digestion of ensiled sorghum forage, can have a beneficial effect both in enhancing methane production (an increase of 25% on methane production was observed, if compared to that of untreated sorghum) and in giving more stability to the anaerobic digestion process. PMID:23867533

Sambusiti, C; Ficara, E; Malpei, F; Steyer, J P; Carrère, H

2013-06-30

290

Organics removal from landfill leachate and activated sludge production in SBR reactors  

SciTech Connect

This study is aimed at estimating organic compounds removal and sludge production in SBR during treatment of landfill leachate. Four series were performed. At each series, experiments were carried out at the hydraulic retention time (HRT) of 12, 6, 3 and 2 d. The series varied in SBR filling strategies, duration of the mixing and aeration phases, and the sludge age. In series 1 and 2 (a short filling period, mixing and aeration phases in the operating cycle), the relationship between organics concentration (COD) in the leachate treated and HRT was pseudo-first-order kinetics. In series 3 (with mixing and aeration phases) and series 4 (only aeration phase) with leachate supplied by means of a peristaltic pump for 4 h of the cycle (filling during reaction period) - this relationship was zero-order kinetics. Activated sludge production expressed as the observed coefficient of biomass production (Y {sub obs}) decreased correspondingly with increasing HRT. The smallest differences between reactors were observed in series 3 in which Y {sub obs} was almost stable (0.55-0.6 mg VSS/mg COD). The elimination of the mixing phase in the cycle (series 4) caused the Y {sub obs} to decrease significantly from 0.32 mg VSS/mg COD at HRT 2 d to 0.04 mg VSS/mg COD at HRT 12 d. The theoretical yield coefficient Y accounted for 0.534 mg VSS/mg COD (series 1) and 0.583 mg VSS/mg COD (series 2). In series 3 and 4, it was almost stable (0.628 mg VSS/mg COD and 0.616 mg VSS/mg COD, respectively). After the elimination of the mixing phase in the operating cycle, the specific biomass decay rate increased from 0.006 d{sup -1} (series 3) to 0.032 d{sup -1} (series 4). The operating conditions employing mixing/aeration or only aeration phases enable regulation of the sludge production. The SBRs operated under aerobic conditions are more favourable at a short hydraulic retention time. At long hydraulic retention time, it can lead to a decrease in biomass concentration in the SBR as a result of cell decay. On the contrary, in the activated sludge at long HRT, a short filling period and operating cycle of the reactor with the mixing and aeration phases seem the most favourable.

Klimiuk, Ewa [University of Warmia and Mazury in Olsztyn, Faculty of Environmental Sciences and Fisheries, Department of Environmental Biotechnology, Sloneczna St. 45G, 10-957 Olsztyn (Poland); Kulikowska, Dorota [University of Warmia and Mazury in Olsztyn, Faculty of Environmental Sciences and Fisheries, Department of Environmental Biotechnology, Sloneczna St. 45G, 10-957 Olsztyn (Poland)]. E-mail: dorotak@uwm.edu.pl

2006-07-01

291

A Feasibility Study of a Steam Methane Reforming Hydrogen Production Plant with a Sodium-Cooled Fast Reactor  

SciTech Connect

A thermal source for hydrogen production is an attractive utilization of nuclear energy. Hydrogen production from natural gas is a promising method in an early stage of hydrogen society, though hydrogen production with water splitting without carbon dioxide emission is the final goal. Steam methane reforming is a well-known method for producing hydrogen from natural gas. A hydrogen separation membrane makes the reforming temperature much lower than that of the equilibrium condition, and a sodium-cooled fast reactor, which supplies heat at {approx}500 deg. C, can be used as a heat source for hydrogen production.In this study, a hydrogen production plant with the membrane reforming method using a sodium-cooled reactor as a thermal source has been designed, and its economic potential is roughly evaluated. The hydrogen production cost is estimated to be about $1.67/kg, achieving the economic target of $1.7/kg. The construction cost is largely shared by the reformers' cost, and it can be decreased using a more efficient hydrogen separation membrane. This shows that steam methane reforming hydrogen production with a sodium-cooled reactor has high economical potential.

Chikazawa, Yoshitaka [Japan Nuclear Cycle Development Institute (Japan); Konomura, Mamoru [Japan Nuclear Cycle Development Institute (Japan); Uchida, Shouji [Advanced Reactor Technology Company, Ltd. (Japan); Sato, Hiroyuki [Mitsubishi Heavy Industries, Ltd. (Japan)

2005-12-15

292

Feasibility Study of Supercritical Light Water Cooled Reactors for Electrical Power Production, 5th Quarterly Report, October - December 2002  

SciTech Connect

The overall objective of this project is to evaluate the feasibility of supercritical light water cooled reactors for electric power production. The use of light water at supercritical pressures as the coolant in a nuclear reactor offers the potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies for the power conversion cycle are possible (i.e. up to about 45%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type re-circulation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel and smaller containment building than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed. If no additional moderator is added to the fuel rod lattice, it is possible to attain fast neutron energy spectrum conditions in a supercritical water-cooled reactor (SCWR). This type of core can make use of either fertile or fertile-free fuel and retain a hard spectrum to effectively burn plutonium and minor actinides from LWR spent fuel while efficiently generating electricity. One can also add moderation and design a thermal spectrum SCWR that can also burn actinides. The project is organized into three tasks:

Philip MacDonald; Jacopo Buongiorno; Cliff Davis; J. Stephen Herring; Kevan Weaver; Ron Latanision; Bryce Mitton; Gary Was; Luca Oriani; Mario Carelli; Dmitry Paramonov; Lawrence Conway

2003-01-01

293

Effects of plastic composite support and pH profiles on pullulan production in a biofilm reactor.  

PubMed

Pullulan is a linear homopolysaccharide which is composed of glucose units and often described as alpha-1, 6-linked maltotriose. The applications of pullulan range from usage as blood plasma substitutes to environmental pollution control agents. In this study, a biofilm reactor with plastic composite support (PCS) was evaluated for pullulan production using Aureobasidium pullulans. In test tube fermentations, PCS with soybean hulls, defatted soy bean flour, yeast extract, dried bovine red blood cells, and mineral salts was selected for biofilm reactor fermentation (due to its high nitrogen content, moderate nitrogen leaching rate, and high biomass attachment). Three pH profiles were later applied to evaluate their effects on pullulan production in a PCS biofilm reactor. The results demonstrated that when a constant pH at 5.0 was applied, the time course of pullulan production was advanced and the concentration of pullulan reached 32.9 g/L after 7-day cultivation, which is 1.8-fold higher than its respective suspension culture. The quality analysis demonstrated that the purity of produced pullulan was 95.8% and its viscosity was 2.4 centipoise. Fourier transform infrared spectroscopy spectra also supported the supposition that the produced exopolysaccharide was mostly pullulan. Overall, this study demonstrated that a biofilm reactor can be successfully implemented to enhance pullulan production and maintain its high purity. PMID:19936738

Cheng, Kuan-Chen; Demirci, Ali; Catchmark, Jeffrey M

2009-11-20

294

Feasibility study Part I - Thermal hydraulic analysis of LEU target for ⁹⁹Mo production in Tajoura reactor  

Microsoft Academic Search

The Renewable Energies and Water Desalination Research Center (REWDRC), Libya, will implement the technology for ⁹⁹Mo isotope production using LEU foil target, to obtain new revenue streams for the Tajoura nuclear research reactor and desiring to serve the Libyan hospitals by providing the medical radioisotopes. Design information is presented for LEU target with irradiation device and irradiation Beryllium (Be) unit

F. M. Bsebsu; F. Abotweirat; S. Elwaer

2008-01-01

295

CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS\\/CO2  

Microsoft Academic Search

There are a number of exothermic chemical reactions which might benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. A particularly promising area is production of oxygenated chemicals, such as alcohols and ethers, from synthesis gas, which can be economically produced from coal or biomass. The ebullated bed operation requires that the

Peizheng Zhou

2000-01-01

296

CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS\\/CO2  

Microsoft Academic Search

There are a number of exothermic chemical reactions which might benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. A particularly promising area is production of oxygenated chemicals, such as alcohols and ethers, from synthesis gas, which can be economically produced from coal or biomass. The ebullated bed operation requires that the

Peizheng Zhou

2001-01-01

297

Safety Issues at the Defense Production Reactors. A Report to the U.S. Department of Energy.  

ERIC Educational Resources Information Center

This report provides an assessment of safety management, safety review, and safety methodology employed by the Department of Energy (DOE) and private contractors. Chapter 1, "The DOE Safety Framework," examines safety objectives for production reactors and processes to implement the objectives. Chapter 2, "Technical Issues," focuses on a variety…

National Academy of Sciences - National Research Council, Washington, DC. Commission on Physical Sciences, Mathematics, and Resources.

298

Safety Issues at the Defense Production Reactors. A Report to the U.S. Department of Energy.  

ERIC Educational Resources Information Center

|This report provides an assessment of safety management, safety review, and safety methodology employed by the Department of Energy (DOE) and private contractors. Chapter 1, "The DOE Safety Framework," examines safety objectives for production reactors and processes to implement the objectives. Chapter 2, "Technical Issues," focuses on a variety…

National Academy of Sciences - National Research Council, Washington, DC. Commission on Physical Sciences, Mathematics, and Resources.

299

Letter report: Title listing of daily operating data on Hanford single-pass reactors, 1944--1971. Hanford Environmental Dose Reconstruction Project  

SciTech Connect

The primary objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that populations and individuals could have received as a result of emissions from Hanford Site operations since 1944, with descriptions of the uncertainties inherent in such estimates. A secondary objective is to make project documentation and Hanford-originated references used in the reports available to the public. Hanford-originated documents of potential interest and/or use to the HEDR Project are made publicly available through the US Government`s National Technical Information Service and placed in the US Department of Energy Richland Field Office (RL) Public Reading Room in Richland, Washington. Project work is conducted under several technical tasks, among which is the Source Terms Task. Under this task, estimates of radioactive emissions from Hanford facilities since 1944 are developed. These estimates are based on historical measurements and production information. The Information Resources Task identifies and retrieves historical production operating information for developing source terms. The purpose of this letter report is to identify documents that record daily reactor operating information at the Hanford Site for the years 1944--1971. Complete bibliographic citations and sample pages from each different format for Hanford reactor operations data are included.

Gydesen, S.P.

1992-02-01

300

Studies on preparation of 64 Cu using (n,?) route of reactor production using medium flux research reactor in India  

Microsoft Academic Search

64Cu (t1\\/2 12.7 h) is a versatile radionuclide owing to its unique decay scheme and exhibits three types of decay electron capture (41%),\\u000a ?? (40%), ?+ (19%) that is useful in nuclear medicine applications. Different batches of natural copper oxide (CuO) and 99.9% enriched\\u000a 63CuO targets were irradiated in research reactors at a neutron flux of 6.6 × 1012 n cm?2 s?1 for duration of 3 days.

K. V. Vimalnath; A. Rajeswari; Viju Chirayil; P. L. Sharad; K. C. Jagadeesan; P. V. Joshi; Meera Venkatesh

301

Separation Requirements for a Hydrogen Production Plant and High-Temperature Nuclear Reactor  

SciTech Connect

This report provides the methods, models, and results of an evaluation for locating a hydrogen production facility near a nuclear power plant. In order to answer the risk-related questions for this combined nuclear and chemical facility, we utilized standard probabilistic safety assessment methodologies to answer three questions: what can happen, how likely is it, and what are the consequences? As part of answering these questions, we developed a model suitable to determine separation distances for hydrogen process structures and the nuclear plant structures. Our objective of the model-development and analysis is to answer key safety questions related to the placement of one or more hydrogen production plants in the vicinity of a high-temperature nuclear reactor. From a thermal-hydraulic standpoint we would like the two facilities to be quite close. However, safety and regulatory implications force the separation distance to be increased, perhaps substantially. Without answering these safety questions, the likelihood for obtaining a permit to construct and build such as facility in the U.S. would be questionable. The quantitative analysis performed for this report provides us with a scoping mechanism to determine key parameters related to the development of a nuclear-based hydrogen production facility. From our calculations, we estimate that when the separation distance is less than 100m, the core damage frequency is large enough (greater than 1E-6/yr) to become problematic in a risk-informed environment. However, a variety of design modifications, for example blast-deflection barriers, were explored to determine the impact of potential mitigating strategies. We found that these mitigating cases may significantly reduce risk and should be explored as the design for the hydrogen production facility evolves.

Curtis Smith; Scott Beck; Bill Galyean

2005-09-01

302

Production of ?-carotene from beet molasses by Blakeslea trispora in stirred-tank and bubble column reactors  

Microsoft Academic Search

The effect of aeration rate and agitation speed on ?-carotene production from molasses by Blakeslea trispora in a stirred-tank fermentor and optimization of the production of the pigment in a bubble column reactor were investigated.\\u000a In addition, a central composite design was employed to determine the maximum ?-carotene concentration at optimum values for\\u000a the process variables (aeration rate, sugar concentration,

Yekta Goksungur; Fani Mantzouridou; Triantafyllos Roukas; Parthena Kotzekidou

2004-01-01

303

Production of H 2 from catalytic partial oxidation of H 2S in a short-contact-time reactor  

Microsoft Academic Search

Partial oxidation of H2S over alumina catalysts in a short-contact-time reactor (SCTR) has been shown to yield hydrogen, sulfur and water as the predominant products. At a set temperature of 400 °C and a contact time of 13 ms, the conversion of H2S is 64.6% with a H2 selectivity of 20.8%, while the amount of SO2 in the products was

P. D. Clark; N. I. Dowling; M. Huang

2004-01-01

304

Nonisothermal reactors for the production of pure water from peritoneal dialysis waste waters.  

PubMed

The diffusion of peritoneal dialysis (PD) at home is somewhat restricted by the difficulty of transport and storage of a large amount of dialytic solutions. This problem is exacerbated in the case of hemodialysis. With the aim of producing pure water to be used in preparing the solution for peritoneal dialysis, or for hemodialysis in general, as one example, we purified the spent dialysate solution from PD. Experiments were carried out with 24 dialysate solutions taken from 8 patients. Pure water was obtained by means of a thermodialysis process in a hollow fiber reactor operating under nonisothermal conditions. Results show that the yield of the nonisothermal process is dependent on the temperature difference applied across the hydrophobic membranes. The production of pure water per square meter of membrane and per hour was equal to 0.55 or 1.2 or 2.0 liters, with a temperature difference of 11 degrees C or 21 degrees C or 28 degrees C, respectively. These results encourage the use of the thermodialysis process in the production of pure water for clinical uses. PMID:17295193

Diano, N; Ettari, G; Grano, V; Gaeta, F S; Rossi, S; Bencivenga, U; D'Alterio, C; Ruocco, G; Mita, L; De Santo, N G; Canciglia, P; Mita, D G

2007-01-01

305

Effect of slurry in cat cracking reactor on product yield and quality  

SciTech Connect

Cracking on microbead zeolitic catalysts is becoming one of the most extensively used processes in petroleum refining. Many paths have been taken in improving the cat cracking process. One of these paths is based on logical application of the principles of physicochemical technology. Feasibility was demonstrated for intensifying the catalytic cracking of vacuum distillate by means of various activating additives, mainly refinery by-products, added to the feed in certain concentrations. By varying the concentration of the additive, the process parameters can be regulated. Of the various parameters, the coke deposition on the catalyst is the most sensitive to the action of additives. We have investigated the possibility of intensifying the cat cracking process by optimizing the quantity of slurry fed to the trapping device of the reactor. It was assumed that the slurry acts in the same manner as additions of products from a different source. In a laboratory unit, we determined the effect of small concentrations of slurry on the material balance in cracking.

Useinova, M.S.; Guseinov, A.M.; Kapustin, V.M. [and others

1994-07-01

306

Co-composting of eggshell waste in self-heating reactors: Monitoring and end product quality.  

PubMed

Industrial eggshell waste (ES) is classified as an animal by-product not intended to human consumption. For reducing pathogen spreading risk due to soil incorporation of ES, sanitation by composting is a pre-treatment option. This work aims to evaluate eggshell waste recycling in self-heating composting reactors and investigate ES effect on process evolution and end product quality. Potato peel, grass clippings and rice husks were the starting organic materials considered. The incorporation of 30% (w/w) ES in a composting mixture did not affect mixture biodegradability, nor its capacity to reach sanitizing temperatures. After 25days of composting, ES addition caused a nitrogen loss of about 10gNkg(-1) of initial volatile solids, thus reducing nitrogen nutritional potential of the finished compost. This study showed that a composting mixture with a significant proportion of ES (30% w/w) may be converted into calcium-rich marketable compost to neutralize soil acidity and/or calcium deficiencies. PMID:24055972

Soares, Micaela A R; Quina, Margarida M J; Quinta-Ferreira, Rosa M

2013-09-04

307

Nitrous oxide production from sequencing batch reactor sludge under nitrifying conditions: effect of nitrite concentrations.  

PubMed

Nitrous oxide (N2O), a greenhouse gas which contributes to the destruction of the stratospheric ozone layer, can be emitted from nitrifying processes during wastewater treatment. The pathway of N2O production was studied using a lab-scale nitrifying reactor. Allylthiourea was used to inhibit NH4+ oxidation and provide information on processes that happen under nitrifying condition. Our study confirmed that besides heterotrophic bacteria, ammonium-oxidizing bacteria could perform denitrification processes, during which NO2- was the electron acceptor and NH4+ was the electron donor, with N2 and N2O as final products. The relative contribution of the heterotrophic denitrification process to total N2O emissions varied from 46.1% to 60.4% depending on NO2(-)-N addition. Correspondingly, 21.8% to 51.5% of total N2O emissions can be attributed to nitrifier denitrification. Little N2O is emitted during the NO2- oxidation process. PMID:22629611

Gong, Youkui; Wang, Shuying; Wang, Sai; Peng, Yongzhen

308

Enhanced production of recombinant aspartase of Aeromonas media NFB-5 in a stirred tank reactor.  

PubMed

Aspartase gene (aspA) from Aeromonas media NFB-5 was cloned and expressed in Escherichia coli BL21 using pET21b(+) expression vector. Maximum production of aspartase was obtained at shake-flask after 5h of IPTG (1.5mM) induction at 37°C and by supplementing the media with KH2PO4 (0.3%, w/v) and K2HPO4 (0.3%, w/v). Further production was investigated at a laboratory scale stirred tank reactor using response surface methodology (RSM). Agitation (130-270rpm), aeration (0.30-1.70vvm) and IPTG induction time (3-7h) was optimized. Optimal levels of agitation (250rpm), aeration (1.25vvm) and induction time (6h) were determined by statistical analysis of the experimental data. More than 7-fold increase in recombinant aspartase (1234U/g wet weight) was observed than the parent strain (172U/g wet wt). Homogenized immobilized permeabilized recombinant cells (566mg/g wet cells) produced more l-aspartic acid as compared to permeabilized recombinant free cells (154mg/g wet cells). PMID:23219690

Singh, Ram Sarup; Yadav, Mukesh

2012-11-17

309

Production and physicochemical properties of functional-butterfat through enzymatic interesterification in a continuous reactor.  

PubMed

Modified-butterfat (MBF) was synthesized with four blends (8:6:6, 6:6:8, 6:6:9, and 4:6:10, by weight) of anhydrous butterfat (ABF), palm stearin (PS) and flaxseed oil (FSO) through enzymatic interesterification in a continuous packed-bed reactor. Flow rate effect of 3, 5, 8 and 10 mL/min on enzymatic interesterification was investigated. By increasing the enzyme contact time with substrates (decreased flow rates), not only did melting and crystallization points shift to lower temperature but also the equivalent carbon number, ECN 36-38 from FSO decreased. Further all reactions were performed at flow rate of 5 mL/min (contact time 140 min) in a continuous reactor packed with 150 g of Lipozyme RM IM. After short path distillation, alpha-linolenic acid composition (%) of 8:6:6, 6:6:8, 6:6:9, and 4:6:10 MBFs were 16, 21, 23 and 25%, respectively. The contents of ECN 36-38, and ECN 48-50 decreased in the blends and MBFs for each substrate ratio. ECN 42-46 in the newly produced TAG increased. Melting points of MBFs were 38 degrees C (8:6:6), 35.5 degrees C (6:6:8), 34 degrees C (6:6:9), and 32 degrees C (4:6:10). MBFs interesterified with FSO contained phytosterols (17-36 mg/100 g) and tocopherols (116-173 microg/g). The products of 8:6:6, 6:6:8, 6:6:9 and 4:6:10 MBFs were softer (69, 88, 80, and 92%, respectively) than pure butterfat at refrigeration temperature. The polymorphic form changed from beta form (blends) to desirable crystalline structure of beta' form (MBFs). Crystal morphology of MBFs also changed and was composed of small spherulites of varying density. PMID:19138078

Shin, Jung-Ah; Akoh, Casimir C; Lee, Ki-Teak

2009-02-11

310

Radioactive Fission Product Release from Defective Light Water Reactor Fuel Elements  

SciTech Connect

Results are provided of the experimental investigation of radioactive fission product (RFP) release, i.e., krypton, xenon, and iodine radionuclides from fuel elements with initial defects during long-term (3 to 5 yr) irradiation under low linear power (5 to 12 kW/m) and during special experiments in the VK-50 vessel-type boiling water reactor.The calculation model for the RFP release from the fuel-to-cladding gap of the defective fuel element into coolant was developed. It takes into account the convective transport in the fuel-to-cladding gap and RFP sorption on the internal cladding surface and is in good agreement with the available experimental data. An approximate analytical solution of the transport equation is given. The calculation dependencies of the RFP release coefficients on the main parameters such as defect size, fuel-to-cladding gap, temperature of the internal cladding surface, and radioactive decay constant were analyzed.It is shown that the change of the RFP release from the fuel elements with the initial defects during long-term irradiation is, mainly, caused by fuel swelling followed by reduction of the fuel-to-cladding gap and the fuel temperature. The calculation model for the RFP release from defective fuel elements applicable to light water reactors (LWRs) was developed. It takes into account the change of the defective fuel element parameters during long-term irradiation. The calculation error according to the program does not exceed 30% over all the linear power change range of the LWR fuel elements (from 5 to 26 kW/m)

Konyashov, Vadim V.; Krasnov, Alexander M. [State Scientific Centre of Russian Federation-Research Institute of Atomic Reactors (Russian Federation)

2002-04-15

311

ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS, AND THE FEDERAL GOVERNMENT - 11052  

SciTech Connect

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River (SRS) near Aiken, South Carolina. Nuclear weapons material production began in the early 1950s, utilizing five production reactors. In the early 1990s all SRS production reactor operations were terminated. The first reactor closure end state declaration was recently institutionalized in a Comprehensive Environmental Response and Compensation and Liability Act (CERCLA) Early Action Record of Decision. The decision for the final closure of the 318,000 square foot 105-P Reactor was determined to be in situ decommissioning (ISD). ISD is an acceptable and cost effective alternative to off-site disposal for the reactor building, which will allow for consolidation of remedial action wastes generated from other cleanup activities within the P Area. ISD is considered protective by the regulators, U. S. Environmental Protection Agency (US EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC), public and stakeholders as waste materials are stabilized/immobilized, and radioactivity is allowed to naturally decay, thus preventing future exposure to the environment. Stakeholder buy-in was critical in the upfront planning in order to achieve this monumental final decision. Numerous public meetings and workshops were held in two different states (covering a 200 mile radius) with stakeholder and SRS Citizens Advisory Board participation. These meetings were conducted over an eight month period as the end state decision making progressed. Information provided to the public evolved from workshop to workshop as data became available and public input from the public meetings were gathered. ISD is being considered for the balance of the four SRS reactors and other hardened facilities such as the chemical Separation Facilities (canyons).

Bergren, C.; Flora, M.; Belencan, H.

2010-11-17

312

ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS AND THE FEDERAL GOVERNMENT  

SciTech Connect

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River (SRS) near Aiken, South Carolina. Nuclear weapons material production began in the early 1950s, utilizing five production reactors. In the early 1990s all SRS production reactor operations were terminated. The first reactor closure end state declaration was recently institutionalized in a Comprehensive Environmental Response and Compensation and Liability Act (CERCLA) Early Action Record of Decision. The decision for the final closure of the 318,000 square foot 105-P Reactor was determined to be in situ decommissioning (ISD). ISD is an acceptable and cost effective alternative to off-site disposal for the reactor building, which will allow for consolidation of remedial action wastes generated from other cleanup activities within the P Area. ISD is considered protective by the regulators, U. S. Environmental Protection Agency (US EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC), public and stakeholders as waste materials are stabilized/immobilized, and radioactivity is allowed to naturally decay, thus preventing future exposure to the environment. Stakeholder buy-in was critical in the upfront planning in order to achieve this monumental final decision. Numerous public meetings and workshops were held in two different states (covering a 200 mile radius) with stakeholder and SRS Citizens Advisory Board participation. These meetings were conducted over an eight month period as the end state decision making progressed. Information provided to the public evolved from workshop to workshop as data became available and public input from the public meetings were gathered. ISD is being considered for the balance of the four SRS reactors and other hardened facilities such as the chemical processing canyons.

Bergren, C

2009-01-16

313

Design of an Online, Multispectrometer Fission Product Monitoring System (FPMS) to Support Advanced Gas Reactor (AGR) Fuel Testing and Qualification in the Advanced Test Reactor  

SciTech Connect

The US Department of Energy (DOE) is embarking on a series of tests of tristructural isotropic (TRISO) coated-particle reactor fuel for the advanced gas reactor (AGR). As one part of this fuel development program, a series of eight fuel irradiation tests are planned for the Idaho National Laboratory's (INL's) advanced test reactor (ATR). The first test in this series (AGR-1) will incorporate six separate capsules irradiated simultaneously, each containing about 51,000 TRISO-coated fuel particles supported in a graphite matrix and continuously swept with inert gas during irradiation. The effluent gas from each of the six capsules must be independently monitored in near real time and the activity of various fission gas nuclides determined and reported. A set of seven heavily-shielded, high-purity germanium (HPGe) gamma-ray spectrometers and sodium iodide [NaI(Tl)] scintillation detector-based total radiation detectors have been designed and are being configured and tested for use during the AGR-1 experiment. The AGR-1 test specification requires that the fission product monitoring system (FPMS) have sufficient sensitivity to detect the failure of a single coated fuel particle and sufficient range to allow it to "count" multiple (up to 250) successive particle failures. This paper describes the design and expected performance of the AGR-1 FPMS.

John K. Hartwell

2007-06-01

314

Dynamic simulation of a tubular reactor for the production of low-density polyethylene using adaptive method of lines  

NASA Astrophysics Data System (ADS)

The dynamic mathematical model of a tubular reactor for the production of low-density polyethylene (LDPE) is introduced and simulation studies of a LDPE plant are presented. The plant consists of the tubular reactor, compressors, heat exchangers and material recycles. The overall model formulation comprises differential, partial differential and algebraic equations. This model formulation is transformed into a DAE system using an adaptive method of lines approach, where the grid points may change their position but their number remains constant. With this technique a solution on a standard PC is possible.

Hafele, M.; Kienle, A.; Boll, M.; Schmidt, C.-U.; Schwibach, M.

2005-11-01

315

H 2 production by steam-quenching of Zn vapor in a hot-wall aerosol flow reactor  

Microsoft Academic Search

Hydrogen production by steam-hydrolysis of zinc is investigated as part of a two-step water-splitting thermochemical cycle based on ZnO\\/Zn redox reactions. The hydrolysis reactor consists of a hot-wall tube containing a flow of Zn(g) that is steam-quenched to co-produce H2 and Zn\\/ZnO nanoparticles. The effects of the quenching gas flow rate and reactor wall temperature on the Zn-to-ZnO chemical conversion

T. Melchior; N. Piatkowski; A. Steinfeld

2009-01-01

316

Nuclear Reactors. Revised.  

ERIC Educational Resources Information Center

|This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

Hogerton, John F.

317

Nuclear Reactors. Revised.  

ERIC Educational Resources Information Center

This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

Hogerton, John F.

318

Continuous methane fermentation and the production of vitamin B12 in a fixed-bed reactor packed with loofah.  

PubMed

A fixed-bed reactor with acclimated methanogens immobilized on a loofah support was studied on a laboratory scale to evaluate the system producing methane from the mixture of CO(2) and H(2) gas, with the production of vitamin B(12) as a by-product. Fermentation using CO(2)/H(2) acclimated methanogens was conducted in a jar fermentor with hydraulic retention times (HRTs) of three and six days. The performance of the reactor was mainly dependent on the HRT. With an HRT of three days, the methane production rate and the vitamin B(12) concentration in the culture broth were 6.18 l/l-reactor/h and 2.88 mg/l-culture liquid; these values were 11.96 l/l-reactor/h and 37.54 mg/l-culture liquid for an HRT of six days. A higher total cell mass of methanogens retained 42.5 g dry cell/l-culture liquid was achieved in the HRT of six days. The loofah carrier immobilized almost 95% of the methanogens, which led to a more effective bio-reaction. It was also observed that the fermentation system had a better ability to buffer pH, especially for an HRT of six days. PMID:14766162

Yang, Yingnan; Zhang, Zhenya; Lu, Jun; Maekawa, Takaaki

2004-05-01

319

Corrosion product deposits on boiling-water reactor cladding: Experimental and theoretical investigation of magnetic properties  

NASA Astrophysics Data System (ADS)

Recent Eddy current investigations on the cladding of nuclear fuel pins have shown that the apparent oxide layers are falsified due to unexpected magnetic properties of corrosion product deposits. Analyses by Scanning Electron Microscopy (SEM) or Electron Probe Micro Analysis (EPMA) demonstrated that the deposit layer consists of complex 3-d element oxides (Ni, Mn, Fe) along with Zn, since the reactor operates with a Zn addition procedure to reduce buildup of radiation fields on the recirculation system surfaces. The oxides crystallise in ferritic spinel structures. These spinels are well-known for their magnetic behaviour. Since non-magnetic zinc ferrite (ZnFe2O4) may become magnetic when doped with even small amounts of Ni and/or Mn, their occurrence in the deposit layer has been analyzed. The magnetic permeability of zinc ferrite, trevorite and jacobsite and their solid solutions are estimated by magnetic moment additivity. From the void history examination, the low elevation sample (810 mm) did not face significant boiling during the irradiation cycles suggesting growth of (Mn0.092+Zn0.752+Fe0.293+)[(Fe1.713+Mn0.032+Ni0.132+)O] crystals with theoretical value of the magnetic permeability for the averaged heterogeneous CRUD layer of 9.5 ± 3. Meanwhile, (Mn0.162+Zn0.552+Fe0.293+)[(Fe1.713+Mn0.042+Ni0.252+)O] crystallizes at the mid elevation (1810 mm) with theoretical magnetic permeability for the CRUD layer of 4.2 ± 1.5 at the investigated azimuthal location. These theoretical data are compared with the magnetic permeability of the corrosion product deposited layers gained from reactor pool side Eddy current (EC) analyses (9.0 ± 1.0 for low and 3.5 ± 1.0 for high elevation). The calculated thicknesses and magnetic permeability values of the deposition layers (estimated by MAGNACROX multifrequency EC method) match together with these estimated using an "ion magnetic moment additivity" model.

Orlov, A.; Degueldre, C.; Wiese, H.; Ledergerber, G.; Valizadeh, S.

2011-09-01

320

Fission product iodine release and retention in nuclear reactor accidents— experimental programme at PSI  

NASA Astrophysics Data System (ADS)

Iodine radionuclides constitute one of the most important fission products of uranium and plutonium. If the volatile forms would be released into the environment during a severe accident, a potential health hazard would then ensue. Understanding its behaviour is an important prerequisite for planning appropriate mitigation measures. Improved and extensive knowledge of the main iodine species and their reactions important for the release and retention processes in the reactor containment is thus mandatory. The aim of PSI's radiolytical studies is to improve the current thermodynamic and kinetic databases and the models for iodine used in severe accident computer codes. Formation of sparingly soluble silver iodide (AgI) in a PWR containment sump can substantially reduce volatile iodine fraction in the containment atmosphere. However, the effectiveness is dependent on its radiation stability. The direct radiolytic decomposition of AgI and the effect of impurities on iodine volatilisation were experimentally determined at PSI using a remote-controlled and automated high activity 188W/Re generator (40 GBq/ml). Low molecular weight organic iodides are difficult to be retained in engineered safety systems. Investigation of radiolytic decomposition of methyl iodide in aqueous solutions, combined with an on-line analysis of iodine species is currently under investigation at PSI.

Bruchertseifer, H.; Cripps, R.; Guentay, S.; Jaeckel, B.

2003-01-01

321

Production of ZrC Matrix for Use in Gas Fast Reactor Composite Fuels  

SciTech Connect

Zirconium carbide is being considered as a candidate for inert matrix material in composite nuclear fuel for Gas fast reactors due to its favorable characteristics. ZrC can be produced by the direct reaction of pure zirconium and graphite powders. Such a reaction is exothermic in nature. The reaction is self sustaining once initial ignition has been achieved. The heat released during the reaction is high enough to complete the reaction and achieve partial sintering without any external pressure applied. External heat source is required to achieve ignition of the reactants and maintain the temperature close to the adiabatic temperature to achieve higher levels of sintering. External pressure is also a driving force for sintering. In the experiments described, cylindrical compacts of ZrC were produced by direct combustion reaction. External induction heating combined with varying amounts of external applied pressure was employed to achieve varying degrees of density/porosity. The effect of reactant particle size on the product characteristics was also studied. The samples were characterized for density/porosity, composition and microstructure. (authors)

Vasudevamurthy, Gokul; Knight, Travis W.; Roberts, Elwyn [Nuclear Materials Laboratory, University of South Carolina 300 Main St, Columbia, SC-29208 (United States); Adams, Thad [Savannah River National Laboratory Materials Technology Division Aiken, SC-29808 (United States)

2007-07-01

322

Uncertainties in source term calculations generated by the ORIGEN2 computer code for Hanford Production Reactors  

SciTech Connect

The ORIGEN2 computer code is the primary calculational tool for computing isotopic source terms for the Hanford Environmental Dose Reconstruction (HEDR) Project. The ORIGEN2 code computes the amounts of radionuclides that are created or remain in spent nuclear fuel after neutron irradiation and radioactive decay have occurred as a result of nuclear reactor operation. ORIGEN2 was chosen as the primary code for these calculations because it is widely used and accepted by the nuclear industry, both in the United States and the rest of the world. Its comprehensive library of over 1,600 nuclides includes any possible isotope of interest to the HEDR Project. It is important to evaluate the uncertainties expected from use of ORIGEN2 in the HEDR Project because these uncertainties may have a pivotal impact on the final accuracy and credibility of the results of the project. There are three primary sources of uncertainty in an ORIGEN2 calculation: basic nuclear data uncertainty in neutron cross sections, radioactive decay constants, energy per fission, and fission product yields; calculational uncertainty due to input data; and code uncertainties (i.e., numerical approximations, and neutron spectrum-averaged cross-section values from the code library). 15 refs., 5 figs., 5 tabs.

Heeb, C.M.

1991-03-01

323

First production of ultracold neutrons with a solid deuterium source at the pulsed reactor TRIGA Mainz?  

NASA Astrophysics Data System (ADS)

The production rates of ultracold neutrons (UCN) with a solid deuterium converter have been measured at the pulsed reactor TRIGA Mainz. Exposed to a thermal neutron fluence of ensuremath ˜ 1\\cdot 10^{13} n·cm^-2·pulse^-1, the number of detected very cold and ultracold neutrons ranges up to 200 000 at 7mol of solid deuterium (sD2) in combination with a pre-moderator (mesitylene). About 50% of the measured neutrons can be assigned to UCN with energies E of ensuremath V_F(sD_2)? E ? V_F(guide) where V F( sD 2) = 105 neV and V F( guide) = 190 neV are the Fermi potentials of the sD2 converter and our stainless steel neutron guides, respectively. Thermal cycling of solid deuterium, which was frozen out from the gas phase, considerably improved the UCN yield, in particular at higher amounts of sD2.

Frei, A.; Sobolev, Yu.; Altarev, I.; Eberhardt, K.; Gschrey, A.; Gutsmiedl, E.; Hackl, R.; Hampel, G.; Hartmann, F. J.; Heil, W.; Kratz, J. V.; Lauer, Th.; Li?on Aguilar, A.; Müller, A. R.; Paul, S.; Pokotilovski, Yu.; Schmid, W.; Tassini, L.; Tortorella, D.; Trautmann, N.; Trinks, U.; Wiehl, N.

2007-11-01

324

Catalytic reformer-combustor: A novel reactor concept for synthesis gas production  

Microsoft Academic Search

A novel reactor design, so called a reformer-combustor, has been proposed for performing COâ reforming of methane to synthesis gas with high yield and energy efficiency. In this reactor that consists of two interconnected fluidized beds, i.e., reformer and combustor, heat that is needed for the highly endothermic COâ reforming is generated by catalytic combustion of methane over a reforming

L. Mleczko; S. Malcus; T. Wurzel

1997-01-01

325

Production of hydrogen and carbon by solar thermal methane splitting. I. The unseeded reactor  

Microsoft Academic Search

Solar thermal methane splitting was performed in a series of tests with an unseeded low capacity reactor. Effective screening of the reactor window from contact with carbon particles was achieved by application of the tornado flow configuration (J Solar Energy Eng 124 (2002) 206). The tests were performed at atmospheric pressure and at temperatures up to 1320K. An extent of

Meir Kogan; Abraham Kogan

2003-01-01

326

A multi-phase, micro-dispersion reactor for the continuous production of methane gas hydrate  

SciTech Connect

A continuous-jet hydrate reactor originally developed to generate a CO2 hydrate stream has been modified to continuously produce CH4 hydrate. The reactor has been tested in the Seafloor Process Simulator (SPS), a 72-L pressure vessel available at Oak Ridge National Laboratory. During experiments, the reactor was submerged in water inside the SPS and received water from the surrounding through a submersible pump and CH4 externally through a gas booster pump. Thermodynamic conditions in the hydrate stability regime were employed in the experiments. The reactor produced a continuous stream of CH4 hydrate, and based on pressure values and amount of gas injected, the conversion of gas to hydrate was estimated. A conversion of up to 70% was achieved using this reactor.

Taboada Serrano, Patricia L [ORNL; Ulrich, Shannon M [ORNL; Szymcek, Phillip [ORNL; McCallum, Scott [Oak Ridge Associated Universities (ORAU); Phelps, Tommy Joe [ORNL; Palumbo, Anthony Vito [ORNL; Tsouris, Costas [ORNL

2009-01-01

327

Fast Pyrolysis of Poplar Using a Captive Sample Reactor: Effects of Inorganic Salts on Primary Pyrolysis Products  

SciTech Connect

We have constructed a captive sample reactor (CSR) to study fast pyrolysis of biomass. The reactor uses a stainless steel wire mesh to surround biomass materials with an isothermal environment by independent controlling of heating rates and pyrolysis temperatures. The vapors produced during pyrolysis are immediately entrained and transported in He carrier gas to a molecular beam mass spectrometer (MBMS). Formation of secondary products is minimized by rapidly quenching the sample support with liquid nitrogen. A range of alkali and alkaline earth metal (AAEM) and transition metal salts were tested to study their effect on composition of primary pyrolysis products. Multivariate curve resolution (MCR) analysis of the MBMS data shows that transition metal salts enhance pyrolysis of carbohydrates and AAEM salts enhances pyrolysis of lignin. This was supported by performing similar separate studies on cellulose, hemicellulose and extracted lignin. The effect of salts on char formation is also discussed.

Mukarakate, C.; Robichaud, D.; Donohoe, B.; Jarvis, M.; Mino, K.; Bahng, M. K.; Nimlos, M.

2012-01-01

328

Production of human lysozyme in biofilm reactor and optimization of growth parameters of Kluyveromyces lactis K7.  

PubMed

Lysozyme (1,4-?-N-acetylmuramidase) is a lytic enzyme, which degrades the bacterial cell wall. Lysozyme has been of interest in medicine, cosmetics, and food industries because of its anti-bactericidal effect. Kluyveromyces lactis K7 is a genetically modified organism that expresses human lysozyme. There is a need to improve the human lysozyme production by K. lactis K7 to make the human lysozyme more affordable. Biofilm reactor provides high biomass by including a solid support, which microorganisms grow around and within. Therefore, the aim of this study was to produce the human lysozyme in biofilm reactor and optimize the growth conditions of K. lactis K7 for the human lysozyme production in biofilm reactor with plastic composite support (PCS). The PCS, which includes polypropylene, soybean hull, soybean flour, bovine albumin, and salts, was selected based on biofilm formation on PCS (CFU/g), human lysozyme production (U/ml), and absorption of lysozyme inside the support. To find the optimum combination of growth parameters, a three-factor Box-Behnken design of response surface method was used. The results suggested that the optimum conditions for biomass and lysozyme productions were different (27 °C, pH 6, 1.33 vvm for biomass production; 25 °C, pH 4, no aeration for lysozyme production). Then, different pH and aeration shift strategies were tested to increase the biomass at the first step and then secrete the lysozyme after the shift. As a result, the lysozyme production amount (141 U/ml) at 25 °C without pH and aeration control was significantly higher than the lysozyme amount at evaluated pH and aeration shift conditions (p?

Ercan, Duygu; Demirci, Ali

2013-05-09

329

Basic energy efficiency of plasma production in electrical discharge and electron beam reactors  

SciTech Connect

Non-thermal plasma processing is an emerging technology for the abatement of volatile organic compounds (VOCs) and nitrogen oxides (NO{sub x}) in atmospheric pressure gas streams. Either electrical discharge of electron beam methods can produce these plasmas. This paper presents a comparative assessment of various non-thermal plasma reactors. The goal of our project is two-fold: (1) to understand the feasibility and scalability of various non-thermal plasma reactors by focusing on the energy efficiency of the electron and chemical kinetics, and (2) to optimize process parameters and provide performance and economic data. Experimental results using a compact electron beam reactor, pulsed corona reactor and dielectric-barrier discharge will be presented. These reactors have been used to study the removal of NO{sub x} and a wide variety of VOCs. The effects of background gas decomposition and gas temperature on the decomposition chemistry have been studied. The decomposition mechanisms are discussed to illustrate how the chemistry could strongly affect the economics of the process. An analysis of the electron kinetics show that electrical discharge reactors are the most suitable only for processes requiring O radicals. For pollution control applications requiring copious amounts of electrons, ions, N atoms or OH radicals, the sue of electron beam reactors is generally the best way of minimizing the electrical power consumption.

Penetrante, B.M.; Hsiao, M.C.; Bardsley, J.N.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States); Kuthi, A. [Plasma and Materials Technologies, Inc., Chatsworth, CA (United States); Burkhart, C.P.; Bayless, J.R. [First Point Scientific, Inc., Agoura Hills, CA (United States)

1996-11-01

330

Effects of plastic composite support and pH profiles on pullulan production in a biofilm reactor  

Microsoft Academic Search

Pullulan is a linear homopolysaccharide which is composed of glucose units and often described as ?-1, 6-linked maltotriose.\\u000a The applications of pullulan range from usage as blood plasma substitutes to environmental pollution control agents. In this\\u000a study, a biofilm reactor with plastic composite support (PCS) was evaluated for pullulan production using Aureobasidium pullulans. In test tube fermentations, PCS with soybean

Kuan-Chen Cheng; Ali Demirci; Jeffrey M. Catchmark

2010-01-01

331

Burning of Minor Actinides and Fission Products from Spent Nuclear Fuel of Power Plants in Dual-Purpose Fusion Reactor  

Microsoft Academic Search

The paper presents the results of analysis of transmutation of Minor Actinides (MA) and Fission Products (FP) from the Spent Nuclear Fuel (SNF) of nuclear power plants. The transmutation scenario includes repeating periods of neutron irradiation in dual-purpose Fusion Power Reactor-Tokamak (FPRT) with Deuterium-Tritium plasma as neutron source and periods of Partitioning and Reprocessing (P&R) of fuel between the irradiation

N. N. Vasiliev; S. V. Sheludjakov; Yu. S. Shpansky; A. G. Serikov

2003-01-01

332

Integration of methanol steam reforming and combustion in a microchannel reactor for H 2 production: A CFD simulation study  

Microsoft Academic Search

A computational fluid dynamics (CFD) study of the thermal integration of the steam reforming of methanol (SRM) and the combustion of methanol in a catalytic microchannel reactor is presented. This issue is of interest for in situ H2 production for portable power units based on low-temperature PEM fuel cells. Three-dimensional simulations have been carried out under relevant conditions for the

G. Arzamendi; P. M. Diéguez; M. Montes; M. A. Centeno; J. A. Odriozola; L. M. Gandía

2009-01-01

333

Fermentative hydrogen production with a draft tube fluidized bed reactor containing silicone-gel-immobilized anaerobic sludge  

Microsoft Academic Search

A draft tube fluidized bed reactor (DTFBR) containing immobilized cell particles was designed to produce H2 continuously. A synthetic polymer (silicone gel; SC) was used as the primary material to immobilize acclimated anaerobic sludge for H2 production in DTFBR with a working volume of 8L. The DTFBR system was operated at a hydraulic retention time (HRT) of 2.2–8.9h and an

Chi-Neng Lin; Shu-Yii Wu; Jo-Shu Chang

2006-01-01

334

Citrus peel influences the production of an extracellular naringinase by Staphylococcus xylosus MAK2 in a stirred tank reactor  

Microsoft Academic Search

Staphylococcus xylosus MAK2, Gram-positive coccus, a nonpathogenic member of the coagulase-negative Staphylococcus family was isolated from soil and used to produce naringinase in a stirred tank reactor. An initial medium at pH 5.5 and\\u000a a cultivation temperature of 30°C was found to be optimal for enzyme production. The addition of Ca+2 caused stimulation of enzyme activity. The effect of various physico-chemical

Munish Puri; Aneet Kaur; Colin J. Barrow; Ram Sarup Singh

2011-01-01

335

Effect of the shear rate on pullulan production from beet molasses by Aureobasidium pullulans in an airlift reactor  

Microsoft Academic Search

The effect of the shear rate on pullulan production from beet molasses by Aureobasidium pullulans P56 in an airlift reactor was investigated. A maximum polysaccharide concentration (18.5 g\\/L), biomass dry weight (14.0 g\\/L),\\u000a polysaccharide yield (38.5%), and sugar utilization (96%) was achieved at a shear rate of 42 s?1. A. pullulans grown on beet molasses produced a mixture of pullulan

T. Roukas; G. Serris

1999-01-01

336

Fission product transport and behavior during two postulated loss-of-flow transients in the Advanced Test Reactor  

Microsoft Academic Search

The fission product behavior during two postulated loss-of-flow accidents (leading to high- and low-pressure core degradations) in the Advanced Test Reactor (ATR) has been analyzed. These transients are designated ATR transients LCP 15 (high pressure) and LPP9 (low pressure). Normally, transients of this nature would be easily mitigated using existing safety systems and procedures. In these analyses, failure of these

J. P. Adams; M. L. Carboneau; D. L. Hagrman

1993-01-01

337

A hybrid model combining hydrodynamic and biological effects for production of bacterial cellulose with a pilot scale airlift reactor  

Microsoft Academic Search

A hybrid model combining hydrodynamic and biological effects is developed to describe the cultivation of Acetobacter xylinum for bacterial cellulose production in a modified airlift reactor with wire-mesh draft tubes. The hydrodynamic part is essentially a modified tanks-in-series model whose parameters are determined using a tracer response method. The modified tanks-in-series model is based on that the materials in the

Kewei Zuo; Hai-Peng Cheng; Sheng-Chi Wu; Wen-Teng Wu

2006-01-01

338

Non-fossil energy for the production of synthetic fuels from coal. I. Fusion reactor with high temperature steam electrolyzer and gasifier  

Microsoft Academic Search

Fusion reactors could displace a large amount of the coal needed for synthetic fuel production. A unique feature of a fusion reactor is that it can potentially supply high temperature steam in the range of 1000° to 1500°C in a continuous manner. The high temperature steam would be obtained by internal heating of a refractory containing blanket section which would

Steinberg

1978-01-01

339

Non-fossil energy for the production of synthetic fuels from Coal I. Fusion reactor with high temperature steam electrolyzer and gasifier  

Microsoft Academic Search

Fusion reactors could displace a large amount of the coal needed for synthetic fuel production. A unique feature of a fusion reactor is that it can potentially supply high temperature steam in the range of 1000° to 1500°C in a continuous manner. The high temperature steam would be obtained by internal heating of a refractory containing blanket section which would

Steinberg

1980-01-01

340

IN-SITU MONITORING OF PRODUCT STREAMS FROM A SPINNING TUBE-IN-TUBE REACTOR USING A METTLER-TOLEDO REACT-IR  

EPA Science Inventory

A Mettler-Toledo ReactIR system has been used for in-line, real-time monitoring of the product stream from a spinning tube-in-tube reactor (STT®, Kreido Laboratories, Camarillo California). This combination of a process intensified continuous-flow reactor and an in-situ analytic...

341

Low energy continuous reactor separator for the production of ethanol from corn grits/starch and biomass streams. 3rd Quarterly report, October 15, 1994--January 15, 1995.  

National Technical Information Service (NTIS)

This project is an attempt to develop and demonstrate an improved reactor for the production of ethanol from starch and ligno-cellulosic streams. Bio-Process Innovations holds a patent of this reactor technology, and is directing the project. A Continuous...

1995-01-01

342

Investigation of the effects of radiolytic-gas bubbles on the long-term operation of solution reactors for medical-isotope production  

NASA Astrophysics Data System (ADS)

One of the most common and important medical radioisotopes is 99Mo, which is currently produced using the target irradiation technology in heterogeneous nuclear reactors. The medical isotope 99Mo can also be produced from uranium fission using aqueous homogeneous solution reactors. In solution reactors, 99Mo is generated directly in the fuel solution, resulting in potential advantages when compared with the target irradiation process in heterogeneous reactors, such as lower reactor power, less waste heat, and reduction by a factor of about 100 in the generation of spent fuel. The commercial production of medical isotopes in solution reactors requires steady-state operation at about 200 kW. At this power regime, the formation of radiolytic-gas bubbles creates a void volume in the fuel solution that introduces a negative coefficient of reactivity, resulting in power reduction and instabilities that may impede reactor operation for medical-isotope production. A model has been developed considering that reactivity effects are due to the increase in the fuel-solution temperature and the formation of radiolytic-gas bubbles. The model has been validated against experimental results from the Los Alamos National Laboratory uranyl fluoride Solution High-Energy Burst Assembly (SHEBA), and the SILENE uranyl nitrate solution reactor, commissioned at the Commissariat a l'Energie Atomique, in Valduc, France. The model shows the feasibility of solution reactors for the commercial production of medical isotopes and reveals some of the important parameters to consider in their design, including the fuel-solution type, 235U enrichment, uranium concentration, reactor vessel geometry, and neutron reflectors surrounding the reactor vessel. The work presented herein indicates that steady-state operation at 200 kW can be achieved with a solution reactor consisting of 120 L of uranyl nitrate solution enriched up to 20% with 235U and a uranium concentration of 145 kg/m3 in a graphite-reflected cylindrical geometry.

Souto Mantecon, Francisco Javier

343

The Hanford Site New Production Reactor (NPR) economic and demographic baseline forecasts  

SciTech Connect

The objective of this is to present baseline employment and population forecasts for Benton, Franklin, and Yakima Counties. These forecasts will be used in the socioeconomic analysis portion of the New Production Reactor Environmental Impact Statement. Aggregate population figures for the three counties in the study area were developed for high- and low-growth scenarios for the study period 1990 through 2040. Age-sex distributions for the three counties during the study period are also presented. The high and low scenarios were developed using high and low employment projections for the Hanford site. Hanford site employment figures were used as input for the HARC-REMI Economic and Demographic (HED) model to produced baseline employment forecasts for the three counties. These results, in turn, provided input to an integrated three-county demographic model. This model, a fairly standard cohort-component model, formalizes the relationship between employment and migration by using migration to equilibrate differences in labor supply and demand. In the resulting population estimates, age-sex distributions for 1981 show the relatively large work force age groups in Benton County while Yakima County reflects higher proportions of the population in the retirement ages. The 2040 forecasts for all three counties reflect the age effects of relatively constant and low fertility increased longevity, as well as the cumulative effects of the migration assumptions in the model. By 2040 the baby boom population will be 75 years and older, contributing to the higher proportion of population in the upper end age group. The low scenario age composition effects are similar. 13 refs., 5 figs., 9 tabs.

Cluett, C.; Clark, D.C. (Battelle Human Affairs Research Center, Seattle, WA (USA)); Pittenger, D.B. (Demographics Lab., Olympia, WA (USA))

1990-08-01

344

Vented target elements for use in an isotope-production reactor. [LMFBR  

DOEpatents

A method is described for producing tritium gas in a fast breeder reactor cooled with liquid metal. Lithium target material is placed in pins equipped with vents, and tritium gas is recovered from the coolant.

Cawley, W.E.; Omberg, R.P.

1982-08-19

345

Trend analysis of coal gasification product yields in an entrained flow reactor  

SciTech Connect

The coal gasification experiments performed by Bissett (1986) under a wide range of residence time, reaction temperatures and pressures form an excellent data base for either verification or predictive computational models. The experiments have been conducted on the METC advanced gasification facilities reactor. For the steam tests via the primary stream a mixture of pulverized coal and conveying Argon, and via the secondary stream (the annular region) a mixture of steam and Argon are introduced into the reactor. For the carbon dioxide tests, a mixture of pulverized coal and conveying Argon is introduced into the reactor via the primary stream; reactant CO{sub 2} is introduced into the reactor via the secondary stream. 8 refs., 20 figs., 9 tabs.

Celik, I.; Chattree, M.

1989-10-01

346

Studies of Plutonium238 Production at the High Flux Isotope Reactor  

Microsoft Academic Search

The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) is a versatile 85 MW{sub th}, pressurized, light water-cooled and -moderated research reactor. The core consists of two fuel elements, an inner fuel element (IFE) and an outer fuel element (OFE), each constructed of involute fuel plates containing high-enriched-uranium (HEU) fuel (93 wt% ²³U\\/U) in the form of

Oscar Lastres; David Chandler; Joshua J Jarrell; G. Ivan Maldonado

2011-01-01

347

Application of an electrochemical membrane reactor to the thermochemical water splitting IS process for hydrogen production  

Microsoft Academic Search

The Bunsen reaction (SO2 + I2 + 2H2O = H2SO4 + 2HI) in the thermochemical IS process to produce hydrogen was successfully employed using an electrochemical membrane reactor. H2SO4 and HI were concentrated in the anode side and the cathode side of the reactor, respectively. I2 is the dominant bulk of the recycling chemicals in this process, and I2 concentration

Mikihiro Nomura; Seiji Fujiwara; Kazuhiko Ikenoya; Seiji Kasahara; Hayato Nakajima; Shinji Kubo; Gab-Jin Hwang; Ho-Sang Choi; Kaoru Onuki

2004-01-01

348

The production of zinc by thermal dissociation of zinc oxide—solar chemical reactor design  

Microsoft Academic Search

We describe the design, fabrication, and preliminary test of a novel solar chemical reactor for conducting the thermal dissociation of ZnO into zinc and oxygen at above 2000 K. The reactor configuration features a windowed rotating cavity-receiver lined with ZnO particles that are held by centrifugal force. With this arrangement, ZnO is directly exposed to high-flux solar irradiation and serves

P. Haueter; S. Moeller; R. Palumbo; A. Steinfeld

1999-01-01

349

FUNCTION AND PERFORMANCE OF A PRE?REACTOR TO A REACTIVE DISTILLATION COLUMN FOR BIODIESEL PRODUCTION  

Microsoft Academic Search

This article describes an in?depth follow?up to previous studies showing that an oil?methanol mixer prior to an RD reactor played an important role in enhancing the overall performance of the RD reactor system. An in?line static mixer was used for the purpose of providing initial mixing of the reactants, heating the mixture up to the desired operating temperature, and carrying

B. B. He; A. P. Singh; J. C. Thompson

350

Feasibility Study of Supercritical Light Water Cooled Reactors for Electric Power Production  

SciTech Connect

The supercritical water reactor (SCWR) has been the object of interest throughout the nuclear Generation IV community because of its high potential: a simple, direct cycle, compact configuration; elimination of many traditional LWR components, operation at coolant temperatures much higher than traditional LWRs and thus high thermal efficiency. It could be said that the SWR was viewed as the water counterpart to the high temperature gas reactor.

Philip MacDonald; Jacopo Buongiorno; James Sterbentz; Cliff Davis; Robert Witt; Gary Was; J. McKinley; S. Teysseyre; Luca Oriani; Vefa Kucukboyaci; Lawrence Conway; N. Jonsson: Bin Liu

2005-02-13

351

Development of membrane reactor technology for power production with pre-combustion CO 2 capture  

Microsoft Academic Search

Hydrogen membrane reactors are an advanced technology for pre-combustion CO2 capture at gas fired power stations. Developments in the field of membrane manufacturing, bench scale testing, module modeling and technoeconomic evaluations are discussed. Semi-commercial modules with membranes up to 50 cm length are currently available. A bench scale multi-tube membrane reactor with a capacity up to 8 parallel tubes has been

Jan Wilco Dijkstra; Johannis A. Z. Pieterse; Hui Li; Jurriaan Boon; Yvonne C. van Delft; Gunabalan Raju; Gerard Peppink; Ruud W. van den Brink; Daniel Jansen

2011-01-01

352

Fast pyrolysis of palm kernel cake in a closed-tubular reactor: product compositions and kinetic model.  

PubMed

In this study, fast pyrolysis of palm kernel cake (PKC) was carried out in a closed-tubular reactor over a temperature range of 550 to 750°C with various retention times. The pyrolyzing gas products mainly included CO, CO(2), and light hydrocarbons; it is noted that no hydrogen was detected in the product. In order to investigate the reaction pathway, the kinetic lump model of Liden was applied to verify and calculate all rate constants. The results obtained at different temperatures indicated that the rate constant increased with pyrolysis temperature. Furthermore, the experimental results were in good agreement with the proposed mechanism. PMID:21215611

Ngo, Thanh-An; Kim, Jinsoo; Kim, Seung-Soo

2010-12-16

353

Cellulase production by Trichoderma harzianum in static and mixed solid-state fermentation reactors under nonaseptic conditions  

SciTech Connect

Cellulase production from lignocellulosic materials was studied in solid-state cultivation by both static and mixed techniques under nonaseptic conditions. The effects of fermentation conditions, such as moisture content, pH, temperature, and aeration, on cellulase production by Trichoderma harzianum using a mixture of wheat straw (80%) and bran (20%) were investigated. With a moisture content of 74% and a pH of 5.8, 18 IU filter paper activity and 198 IU endoglucanase activity/g initial substrate content were obtained in 66 hours. The extension from static column cultivation to stirred tank reactor of 65 l capacity gave similar yields of cellulase.

Deschamps, F.; Giuliano, C.; Asther, M.; Huet, M.C.; Roussos, S.

1985-09-01

354

A monolithic lipase reactor for biodiesel production by transesterification of triacylglycerides into fatty acid methyl esters  

PubMed Central

An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2 h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10 min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel.

Urban, Jiri; Svec, Frantisek; Frechet, Jean M.J.

2011-01-01

355

Final report on LDRD project : biodiesel production from vegetable oils using slit-channel reactors.  

SciTech Connect

This report documents work done for a late-start LDRD project, which was carried out during the last quarter of FY07. The objective of this project was to experimentally explore the feasibility of converting vegetable (e.g., soybean) oils to biodiesel by employing slit-channel reactors and solid catalysts. We first designed and fabricated several slit-channel reactors with varying channel depths, and employed them to investigate the improved performance of slit-channel reactors over traditional batch reactors using a NaOH liquid catalyst. We then evaluated the effectiveness of several solid catalysts, including CaO, ZnO, MgO, ZrO{sub 2}, calcium gluconate, and heteropolyacid or HPA (Cs{sub 2.5}H{sub 0.5}PW{sub 12}O{sub 40}), for catalyzing the soybean oil-to-biodiesel transesterification reaction. We found that the slit-channel reactor performance improves as channel depth decreases, as expected; and the conversion efficiency of a slit-channel reactor is significantly higher when its channel is very shallow. We further confirmed CaO as having the highest catalytic activity among the solid catalysts tested, and we demonstrated for the first time calcium gluconate as a promising solid catalyst for converting soybean oil to biodiesel, based on our preliminary batch-mode conversion experiments.

Kalu, E. Eric (FAMU-FSU College of Engineering, Tallahassee, FL); Chen, Ken Shuang

2008-01-01

356

Thermal- and Fast-Spectrum Molten Salt Reactors for Actinide Burning and Fuel Production  

SciTech Connect

In a molten salt reactor (MSR), the fuel is dissolved in a fluoride salt coolant. The technology was partly developed in the 1950s and 1960s. With changing goals for advanced reactors and new technologies, there is currently a renewed interest in MSRs. The new technologies include (1) Brayton power cycles (rather than steam cycles) that eliminate many of the historical challenges in building MSRs and (2) the conceptual development of several fast-spectrum MSRs that have large negative temperature and void coefficients, a unique safety characteristic not found in solid-fuel fast reactors. Earlier MSRs were thermal-neutron-spectrum reactors. Compared with solid-fueled reactors, MSR systems have lower fissile inventories, no radiation damage constraint on attainable fuel burnup, no spent nuclear fuel, no requirement to fabricate and handle solid fuel, and a single isotopic composition of fuel in the reactor. These and other characteristics may enable MSRs to have potentially unique capabilities and competitive economics for actinide burning and extending fuel resources. The status, unique characteristics, and recent worldwide advances in MSRs are described.

Forsberg, Charles W [ORNL

2007-01-01

357

Environmental Monitoring Plan United States Department of Energy Richland Operations Office. Revision 2  

SciTech Connect

This Environmental Monitoring Plan was prepared for the US Department of Energy`s (DOE`s) Richland Operations Office (RL) to implement the requirements of DOE Order 5400.1. According to the Order, each DOE site, facility, or activity that uses, generates, releases, or manages significant pollutants or hazardous materials shall prepare a written environmental monitoring plan covering two major activities: (1) effluent monitoring and (2) environmental surveillance. The plan is to contain information discussing the rationale and design criteria for the monitoring programs, sampling locations and schedules, quality assurance requirements, program implementation procedures, analytical procedures, and reporting requirements. The plan`s purpose is to assist DOE in the management of environmental activities at the Hanford Site and to help ensure that operations on the site are conducted in an environmentally safe and sound manner.

NONE

1997-11-10

358

Geologic map of the Richland 1:100,000 quadrangle, Washington  

SciTech Connect

This map of the Richland 1:100,000-scale quadrangle, Washington, shows the geology of one of fifteen complete or partial 1:100,000-scale quadrangles that cover the southeast quadrant of Washington. Geologic maps of these quadrangles have been compiled by geologists with the Washington Division of Geology and Earth Resources (DGER) and Washington State University and are the principal data sources for a 1:250,000-scale geologic map of the southeast quadrant of Washington, which is in preparation. Eleven of these quadrangles are being released as DGER open-file reports. The map of the Wenatchee quadrangle has been published by the US Geological Survey, and the Moses Lake, Ritzville quadrangles have already been released.

Reidel, S.P.; Fecht, K.R. [comps.

1993-09-01

359

Simple automatic device for real time sampling of gas production by a reactor  

SciTech Connect

An innovative automatic device, allowing periodically drawing samples of the gases produced by a generic reactor, is presented. The gases evolving during the reaction are collected in a storage manifold, equipped with a variable volume consisting of a stainless steel bellow, whose expansion or contraction is driven by a linear step motor. A capacitive gauge monitors the pressure inside the storage manifold, while a feedback control loop reacts to any pressure change adjusting the variable volume (by means of the step motor) in such a way to keep the pressure at a desired set point P{sub 0}. As long as the reaction proceeds, the gas production results in a progressive expansion of the variable volume, whose instantaneous value is constantly monitored by means of a slide potentiometer, whose lever is rigidly connected to the bellow's moving extremity. Once the bellow's expansion has reached a predetermined volume increment {delta}V, which means that an amount of gas P{sub 0}{delta}V has been produced and collected in the storage circuit, a quantity P{sub 0}V{sub S}{<=}P{sub 0}{delta}V of gas is released to the analysis system. A set of electropneumatic valves, automatically operated by the control system, allows for gas delivery to the analysis equipment and retrieval of the set point pressure, by compression of the variable volume, with no influence on the reaction. All relevant parameters are monitored and logged on a personal computer. The control and data acquisition software, made out using National Instrument LABVIEW trade mark sign , also provides control of the analysis equipment. The ability of the proposed setup to not affect the ongoing process allows real time monitoring (by drawing samples at regular time intervals during the reaction) of the gas production. Moreover, since the amount of gas P{sub 0}V{sub S} drawn at each sampling is always the same, it is possible to establish at a glance whether or not there are changes in the concentration of any component, by directly comparing the results of the analysis of successive samples.

Frattolillo, A. [ENEA-Unita Tecnico Scientifica Fusione-Centro Ricerche Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy)

2006-06-15

360

The role of pH in the fermentative H2 production from an acidogenic granule-based reactor.  

PubMed

The role of pH in the fermentative H(2) production from an upflow acidogenic granule-based reactor was investigated in this study. Experimental results show that all H(2) partial pressure, H(2) production rate and H(2) yield were pH-dependent, in the range of 2.8 x 10(4)-5.2 x 10(4)Pa, 61-145 ml-H(2)l(-1)h(-1) and 0.68-1.61 mol-H(2)mol-glucose(-1), respectively. The maximum H(2) partial pressure was observed at pH 3.4, while both maximum H(2) production rate and H(2) yield were found at pH 4.2. Acetate, propionate, butyrate, i-butyrate, valerate, caporate and ethanol were present in the effluent of this UASB reactor, and their distribution was also pH-dependent. As pH was decreased from 4.2 to a lower level of 3.4 or increased to a higher level of 6.3, the fermentative type of this H(2)-producing reactor would shift from butyrate-type to caporate- or ethanol-type. Thermodynamic analysis was performed to explore the possible metabolic pathways of caproate and valerate formation. The metabolic pathway of caproate formation was pH-dependent, while that of valerate formation was pH-independent. A neural network model was designed, trained and validated. It was able to successfully describe the daily variations of H(2) partial pressure and H(2) yield of the reactor, and to predict its steady state performance at various pHs. PMID:16466779

Mu, Yang; Yu, Han-Qing; Wang, Yi

2006-02-08

361

Citrus peel influences the production of an extracellular naringinase by Staphylococcus xylosus MAK2 in a stirred tank reactor.  

PubMed

Staphylococcus xylosus MAK2, Gram-positive coccus, a nonpathogenic member of the coagulase-negative Staphylococcus family was isolated from soil and used to produce naringinase in a stirred tank reactor. An initial medium at pH 5.5 and a cultivation temperature of 30°C was found to be optimal for enzyme production. The addition of Ca(+)² caused stimulation of enzyme activity. The effect of various physico-chemical parameters, such as pH, temperature, agitation, and inducer concentration was studied. The enzyme production was enhanced by the addition of citrus peel powder (CPP) in the optimized medium. A twofold increase in naringinase production was achieved using different technological combinations. The process optimization using technological combinations allowed rapid optimization of large number of variables, which significantly improved enzyme production in a 5-l reactor in 34 h. An increase in sugar concentration (15 g?l?¹) in the fermentation medium further increased naringinase production (8.9 IU?ml?¹) in the bioreactor. Thus, availability of naringinase renders it attractive for potential biotechnological applications in citrus processing industry. PMID:20922381

Puri, Munish; Kaur, Aneet; Barrow, Colin J; Singh, Ram Sarup

2010-10-05

362

Solidification of Liquid Concentrate and Solid Waste Generated as by-Products of the Liquid Radwaste Treatment Systems in Light-Water Reactors.  

National Technical Information Service (NTIS)

The treatment of liquid concentrate and solid waste produced in light-water reactors as by-products of liquid radwaste treatment systems consists of five basic operations: waste collection, waste pretreatment, solidification agent handling, mixing/packagi...

R. M. Neilson P. Colombo

1977-01-01

363

Syngas production by thermochemical conversion of CO2 and H2O mixtures using a high-temperature heat pipe based reactor  

NASA Astrophysics Data System (ADS)

The design of a new high-temperature, solar-based reactor for thermochemical production of syngas using water and carbon dioxide will be discussed. The reactor incorporates the use of high-temperature heat pipe(s) that efficiently transfer the heat from a solar collector to a porous metal oxide material. Special attention is given to the thermal characteristics of the reactor, which are key factors affecting the overall system efficiency and amount of fuel produced. The thermochemical cycle that is considered is that for ceria based material. Preliminary data acquired from an early stage reactor, operated at temperatures up to 1100oC, is presented and efforts are now underway to increase the operating temperature of the reactor to 1300oC to further increase the efficiency of the thermochemical fuel production process.

Pearlman, Howard; Chen, Chien-Hua

2012-10-01

364

Public Health Assessment for Palmetto Recycling, Incorporated, Columbia, Richland County, South Carolina, Region 4. CERCLIS No. SCD037398120.  

National Technical Information Service (NTIS)

The Palmetto Recycling Incorporated (PRI) site consists of 1.5 acres of land on Koon Store Road, in a rural area approximately 8 miles north of Columbia in Richland County, South Carolina. The main sources of contamination appear to come from liquids and ...

1995-01-01

365

Citric acid production in a bubble-column reactor using cells of the yeast Candida guilliermondii immobilized by adsorption onto sawdust  

Microsoft Academic Search

Cells of the yeast Candida guilliermondii have been immobilized by adsorption onto sawdust and used in a bubble-column reactor for the continuous production of citric acid. At a dilution rate of 0.21 h?1 in a nitrinogen-limited medium containing glucose, a reactor productivity of 0.24 g l?1 h?1 has been achieved which is twice that observed in a batch fermenter culture

Djadjat Tisnadjaja; Noemi A. Gutierrez; Ian S. Maddox

1996-01-01

366

[Treatment of high-concentration butyl-acrylate-production wastewater by A three-phase biological fluidized bed reactor].  

PubMed

The butyl-acrylate-production wastewater was treated by a three-phase biological fluidized bed reactor. The influences of acrylic acid concentrations, p-toluenesulfonic acid concentrations, volumic load and hydraulic retention time on pollutants removal efficiencies were investigated. It was indicated that the reactor was suitable for the treatment of butyl-acrylate-production wastewater at a high loading rate. Acrylic acid of 100 mg/L or p-toluenesulfonic acid of 50 mg/L in the influent can inhibit the unacclimated microorganisms in the fluidized bed reactor. The inhibition effects were eliminated after an acclimation of two weeks. Acrylic acid and p-toluenesulfonic acid could be removed completely at COD loading rates up to 11.56-13.56 kg/(m3 x d). The effluent COD could satisfy the demand of Class II in Chinese Integrated Wastewater Discharge Standard (GB 8978-1996) at COD loading rates up to 8.86 kg/(m3 x d) when influent COD concentration is below 2000 mg/L. When the influent COD concentration was increased to 9550-11,800 mg/L(acrylic acid of 6244 mg/L and p-toluenesulfonic acid of 1000 mg/L), the effluent COD was 271-360 mg/L, which satisfied the demand of Class III in Chinese Integrated Wastewater Discharge Standard (GB 8978-1996) at COD loading rates of 7.96-9.83 kg/(m3 x d). PMID:21780595

Fan, Zhi-qing; Song, Yu-dong; Zhou, Yue-xi; Liang, Han-dong

2011-05-01

367

Protected Plutonium Production by Transmutation of Minor Actinides for Peace and Sustainable Prosperity—Irradiation Tests of Np and NpU Samples in the Experimental Fast Reactor JOYO (JAEA) and the Advanced Test Reactor at INL—  

Microsoft Academic Search

A project on Protected Plutonium Production (P) was proposed by Tokyo Institute of Technology as part of a nonproliferation research program for plutonium (Pu) utilization in nuclear reactors. The project is aimed at the production of inherently protected Pu by the addition of Np to uranium (U) fuel. In order to validate this P concept, two irradiation tests were performed.

Shin-ichi KOYAMA; Masahiko OSAKA; Masahiko ITOH; Hiroshi SAGARA; Masaki SAITO

2010-01-01

368

Feasibility Study of Supercritical Light Water Cooled Fast Reactors for Actinide Burning and Electric Power Production  

SciTech Connect

The use of supercritical temperature and pressure light water as the coolant in a direct-cycle nuclear reactor offers potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies of the power conversion cycle are possible (i.e. up to 46%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type recirculation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed. If a tight fuel rod lattice is adopted, it is possible to significantly reduce the neutron moderation and attain fast neutron energy spectrum conditions. In this project a supercritical water reactor concept with a simple, blanket-free, pancake-shaped core will be developed. This type of core can make use of either fertile or fertile-free fuel and retain the hard spectrum to effectively burn plutonium and minor actinides from LWR spent fuel while efficiently generating electricity.

Mac Donald, Philip Elsworth; Buongiorno, Jacopo; Davis, Cliff Bybee; Weaver, Kevan Dean

2002-01-01

369

Application of a packed bed reactor for the production of hydrogen from cheese whey permeate: Effect of organic loading rate.  

PubMed

The production of H2 was studied using a packed bed reactor with polyurethane foam acting as support material. Experiments were performed using mixed microflora under non sterile conditions. The system was initially operated with synthetic wastewater as the sole substrate. Subsequently, cheese whey permeate was added to the system at varying organic loading rates (OLR). The performance of the reactor was evaluated by applying a continuous decrease in OLR. As a result, a significant decrease in H2 yields (HY) was observed with the decrease in OLR from 18.8 to 6.3 g chemical oxygen demand (COD)/L d. Microbial analysis demonstrated that the prevalence of non-hydrogen producers, Sporolactobacillus sp. and Prevotella, was the main reason for low HYs obtained. This behavior indicates that the fermentation under non-sterile conditions was favored by high concentrations of substrate by creating an adverse environment for nonhydrogen producer organisms. PMID:24171421

Fernández, Camino; Carracedo, Begoña; Martínez, Elia Judith; Gómez, Xiomar; Morán, Antonio

2014-01-01

370

Continuous hydrogen production from co-digestion of municipal food waste and kitchen wastewater in mesophilic anaerobic baffled reactor.  

PubMed

This study was carried out to assess the impact of organic loading rate (OLR) on the performance of mesophilic anaerobic baffled reactor (ABR) for H(2) production from a co-digestion of municipal food waste and kitchen wastewater. The reactor was operated at different organic loading rates (OLRs) of 29, 36 and 47 g COD(total)/Ld. The hydraulic retention time (HRT) was kept constant at 1.6d. The results showed that increasing the OLR from 29 to 36 g COD(total)/Ld, leads to a significant (p ? 0.01) drop in the H(2) production from 6.0±0.5 to 5.4±1.04 L H(2)/d, respectively. However, the H(2) production remained at the same level of 5.3±1.04 L H(2)/d at increasing the OLR from 36 to 47 g COD(total)/Ld. The H(2) generation was mainly due to conversion of COD (57%) and carbohydrate (81%). Protein and lipids conversion represents only 23.3% and 4.1% respectively for H(2) production. PMID:22446053

Tawfik, A; El-Qelish, M

2012-02-20

371

Comparative Study to Determine an Optimal Material for Tritium Production in a Direct Drive IFE Reactor  

NASA Astrophysics Data System (ADS)

An important technical and economic consideration in designing the prospective direct drive inertial fusion energy (IFE) reactor is the determination of a suitable mechanism for tritium breeding. A comprehensive review is undertaken to determine the optimal breeding material, examining two candidate compounds: 83Pb-17Li and (LiF)2BeF2 (FLiBe). In this study, the compounds are evaluated based on chemical and physical properties, structural requirements, feasibility, hazards, and costs of application. Preliminary results seemed to indicate that FLiBe may be the more practical option, due to its mechanical utility and the relative projected efficacy of blanket design. However, much remains to be investigated, particularly the properties of breeder and structural materials in the specific conditions of a reactor. This evaluation process will require further theoretical modeling as well as practical trial, currently planned in other progenitor reactor designs. This paper will present the results of the analysis of these candidate breeder materials.

Aristova, Maria; Gentile, Charles

2007-11-01

372

Comparison of mesophilic and thermophilic upflow anaerobic sludge blanket reactors treating instant coffee production wastewater  

Microsoft Academic Search

Stable anaerobic digestion of settled instant coffee wastewater was achieved for over 100 days in mesophilic (35°C) and termophilic (55°C) UASB reactors. Thermophilic upflow anaerobic sludge blankets (UASBs) were seeded with mesophilic granules and converted to thermophilic operation by raising the temperature to 55°C in one step. Successful thermophilic operation was achieved within 28 days. Both mesophilic and thermophilic UASBs

Richard M. Dinsdale; Freda R. Hawkes; Dennis L. Hawkes

1997-01-01

373

Hydrogen production for fuel cell application in an autothermal micro-channel reactor  

Microsoft Academic Search

Results concerning the coupling of the steam reforming (SR) and total oxidation (TOX) of methanol in a two-passage reactor are presented. A commercially available copper based catalyst is used for the steam reforming. For the total oxidation, a highly active cobalt oxide catalyst was developed. Both catalysts are used in form of thin layers immobilized on the wall of the

Pierre Reuse; Albert Renken; Katja Haas-Santo; Oliver Görke; Klaus Schubert

2004-01-01

374

Cane molasses fermentation for continuous ethanol production in an immobilized cells reactor by Saccharomyces cerevisiae  

Microsoft Academic Search

Sodium-alginate immobilized yeast was employed to produce ethanol continuously using cane molasses as a carbon source in an immobilized cell reactor (ICR). The immobilization of Saccharomyces cerevisiae was performed by entrapment of the cell cultured media harvested at exponential growth phase (16 h) with 3% sodium alginate. During the initial stage of operation, the ICR was loaded with fresh beads of

Farshid Ghorbani; Habibollah Younesi; Abbas Esmaeili Sari; Ghasem Najafpour

2011-01-01

375

Production of ZrC Matrix for Use in Gas Fast Reactor Composite Fuels  

Microsoft Academic Search

Zirconium carbide is being considered as a candidate for inert matrix material in composite nuclear fuel for Gas fast reactors due to its favorable characteristics. ZrC can be produced by the direct reaction of pure zirconium and graphite powders. Such a reaction is exothermic in nature. The reaction is self sustaining once initial ignition has been achieved. The heat released

Gokul Vasudevamurthy; Travis W. Knight; Elwyn Roberts; Thad Adams

2007-01-01

376

In-Depth Survey Report: Evaluation of Enclosed Reactor for the Production of Aligned Carbon Nanotubes.  

National Technical Information Service (NTIS)

The study site produces aligned carbon nanotubes in an enclosed reactor (Easy Tube 3000, First Nano, Ronkonkoma, NY). Carbon nanotubes are produced so that they are aligned in one direction on a substrate. These are termed 'aligned carbon nanotubes' and t...

C. Beaucham C. Sparks L. M. Low W. A. Heitbrink

2012-01-01

377

Identification of Volatile Reactor Fuel Decomposition Products by Gas Chromatography and Spectral Analysis.  

National Technical Information Service (NTIS)

The gases produced by irradiation of the polyethylene moderated fuel used in the AGN-201 reactor at the Naval Postgraduate School were analyzed for both radioactive and non-radioactive species. The hydrogen content of the gases is higher than that reporte...

L. W. Cole

1968-01-01

378

Feasibility Study of Supercritical Light Water Cooled Reactors for Electric Power Production  

Microsoft Academic Search

The supercritical water reactor (SCWR) has been the object of interest throughout the nuclear Generation IV community because of its high potential: a simple, direct cycle, compact configuration; elimination of many traditional LWR components, operation at coolant temperatures much higher than traditional LWRs and thus high thermal efficiency. It could be said that the SWR was viewed as the water

Philip MacDonald; Jacopo Buongiorno; James Sterbentz; Cliff Davis; Robert Witt; J. McKinley; S. Teysseyre; Luca Oriani; Vefa Kucukboyaci; Lawrence Conway; N. Jonsson; Bin Liu

2005-01-01

379

HYBRID SULFUR CYCLE FLOWSHEETS FOR HYDROGEN PRODUCTION USING HIGH-TEMPERATURE GAS-COOLED REACTORS  

SciTech Connect

Two hybrid sulfur (HyS) cycle process flowsheets intended for use with high-temperature gas-cooled reactors (HTGRs) are presented. The flowsheets were developed for the Next Generation Nuclear Plant (NGNP) program, and couple a proton exchange membrane (PEM) electrolyzer for the SO2-depolarized electrolysis step with a silicon carbide bayonet reactor for the high-temperature decomposition step. One presumes an HTGR reactor outlet temperature (ROT) of 950 C, the other 750 C. Performance was improved (over earlier flowsheets) by assuming that use of a more acid-tolerant PEM, like acid-doped poly[2,2'-(m-phenylene)-5,5'-bibenzimidazole] (PBI), instead of Nafion{reg_sign}, would allow higher anolyte acid concentrations. Lower ROT was accommodated by adding a direct contact exchange/quench column upstream from the bayonet reactor and dropping the decomposition pressure. Aspen Plus was used to develop material and energy balances. A net thermal efficiency of 44.0% to 47.6%, higher heating value basis is projected for the 950 C case, dropping to 39.9% for the 750 C case.

Gorensek, M.

2011-07-06

380

THE INFLUENCE OF DESIGN AND PRODUCTION PARAMETERS ON FABRICATION COSTS OF NUCLEAR REACTOR FUEL ELEMENTS  

Microsoft Academic Search

A study was conducted to determine fuel fabrication and assembly costs ; in a large nuclear power industry for several reactors, fuel rod sizes, and fuel ; materials. The bases and assumptions for development of cost data are discussed ; along with methods for developing cost equations. Results and interpretations ; are included. (J.R.D.);

P. E. Stein; A. C. Ayers; R. J. Braatz; C. M. Bradford; V. D. Holt; G. P. Mattie

1961-01-01

381

Hydrogen-rich gas production from gasoline in a short contact time catalytic reactor  

Microsoft Academic Search

Presented is a study of hydrogen-rich gas generation by selective catalytic oxidation of gasoline in a nearly adiabatic monolith reactor. Experiments were conducted using a gasoline mixture containing 191 hydrocarbon species, while corresponding thermodynamic models employed a surrogate mixture of 29 organics with well-defined properties. Based on the data obtained, it was demonstrated that a nearly equilibrium synthesis gas could

L. Bobrova; I. Zolotarsky; V. Sadykov; V. Sobyanin

2007-01-01

382

Influence of biomass production and detachment forces on biofilm structures in a biofilm airlift suspension reactor  

Microsoft Academic Search

The influence of process conditions (substrate loading rate and detachment force) on the structure of biofilms grown on basalt particles in a Biofilm Airlift Sus- pension (BAS) reactor was studied. The structure of the biofilms (density, surface shape, and thickness) and mi- crobial characteristics (biomass yield) were investigated at substrate loading rates of 5, 10, 15, and 20 kg COD\\/

W. K. Kwok; C. Picioreanu; S. L. Ong; M. C. M. van Loosdrecht; W. J. Ng; J. J. Heijnen

1998-01-01

383

The characteristics of extracellular polymeric substances and soluble microbial products in moving bed biofilm reactor-membrane bioreactor.  

PubMed

The characteristics of extracellular polymeric substances (EPS) and soluble microbial products (SMP) in conventional membrane bioreactor (MBR) and in moving bed biofilm reactor-membrane bioreactors (MBBR-MBR) were investigated in long-term (170days) experiments. The results showed that all reactors had high removal efficiency of ammonium and COD, despite very different fouling conditions. The MBBR-MBR with media fill ratio of 26.7% had much lower total membrane resistance and no obvious fouling were detected during the whole operation. In contrast, MBR and MBBR-MBR with lower and higher media fill experienced more significant fouling. Low fouling at optimum fill ratio may be due to the higher percentage of small molecular size (<1kDa) and lower percentage of large molecular size (>100kDa) of EPS and SMP in the reactor. The composition of EPS and SMP affected fouling due to different O-H bonds in hydroxyl functional groups, and less polysaccharides and lipids. PMID:24077152

Duan, Liang; Jiang, Wei; Song, Yonghui; Xia, Siqing; Hermanowicz, Slawomir W

2013-09-02

384

Wastewater treatment from biodiesel production via a coupled photo-Fenton-aerobic sequential batch reactor (SBR) system.  

PubMed

A coupled system of the photo-Fenton advanced oxidation technique and an aerobic sequential batch reactor (SBR) was used to treat wastewater from biodiesel production using either palm or castor oil. The photo-Fenton reaction and biological process were evaluated individually and were effective at treating the wastewater; nevertheless, each process required longer degradation times for the wastewater pollutants compared with the coupled system. The proposed coupled photo-Fenton/aerobic SBR system obtained a 90% reduction of the chemical oxygen demand (COD) in half of the time required for the biological system individually. PMID:22766873

Ramírez, Ximena María Vargas; Mejía, Gina Maria Hincapié; López, Kelly Viviana Patiño; Vásquez, Gloria Restrepo; Sepúlveda, Juan Miguel Marín

2012-01-01

385

Evaluation of selected ex-reactor accidents related to the tritium and medical isotope production mission at the FFTF  

SciTech Connect

The Fast Flux Test Facility (FFTF) has been proposed as a production facility for tritium and medical isotopes. A range of postulated accidents related to ex-reactor irradiated fuel and target handling were identified and evaluated using new source terms for the higher fuel enrichment and for the tritium and medical isotope targets. In addition, two in-containment sodium spill accidents were re-evaluated to estimate effects of increased fuel enrichment and the presence of the Rapid Retrieval System. Radiological and toxicological consequences of the analyzed accidents were found to be well within applicable risk guidelines.

Himes, D.A.

1997-11-17

386

Book Review: Fission product transport processes in reactor accidents, proceedings to the International Centre for Heat and Mass processes  

SciTech Connect

In the wake of the Chernobyl accident, the Executive Committee of the International Centre for Heat and Mass Transfer decided at its meeting in Tashkent in April 1987 to organize a seminar on fission product transport processes in reactor accidents. The seminar was held in Dubrovnik, Yugoslavia, May 22-26, 1989. Co-sponsoring organizations were the United Nations Educational Scientific and Cultural Organization, Carleton University, and the Boris Kidric Institute of Nuclear Sciences. Twelve invited lectures and forty-seven invited papers were presented. 1 tab.

Kress, T.S. [Martin Marietta Energy Systems, Oak Ridge, TN (United States)

1991-01-01

387

NEUTRONIC REACTOR  

DOEpatents

A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

Wigner, E.P.

1958-04-22

388

ENERGY EFFICIENCY LIMITS FOR A RECUPERATIVE BAYONET SULFURIC ACID DECOMPOSITION REACTOR FOR SULFUR CYCLE THERMOCHEMICAL HYDROGEN PRODUCTION  

SciTech Connect

A recuperative bayonet reactor design for the high-temperature sulfuric acid decomposition step in sulfur-based thermochemical hydrogen cycles was evaluated using pinch analysis in conjunction with statistical methods. The objective was to establish the minimum energy requirement. Taking hydrogen production via alkaline electrolysis with nuclear power as the benchmark, the acid decomposition step can consume no more than 450 kJ/mol SO{sub 2} for sulfur cycles to be competitive. The lowest value of the minimum heating target, 320.9 kJ/mol SO{sub 2}, was found at the highest pressure (90 bar) and peak process temperature (900 C) considered, and at a feed concentration of 42.5 mol% H{sub 2}SO{sub 4}. This should be low enough for a practical water-splitting process, even including the additional energy required to concentrate the acid feed. Lower temperatures consistently gave higher minimum heating targets. The lowest peak process temperature that could meet the 450-kJ/mol SO{sub 2} benchmark was 750 C. If the decomposition reactor were to be heated indirectly by an advanced gas-cooled reactor heat source (50 C temperature difference between primary and secondary coolants, 25 C minimum temperature difference between the secondary coolant and the process), then sulfur cycles using this concept could be competitive with alkaline electrolysis provided the primary heat source temperature is at least 825 C. The bayonet design will not be practical if the (primary heat source) reactor outlet temperature is below 825 C.

Gorensek, M.; Edwards, T.

2009-06-11

389

Conceptual Analysis of the Power Production of Fission Electric Cell Reactors  

SciTech Connect

The United States Department of Energy, Nuclear Energy Research Initiative (NERI) Direct Energy Conversion project has as its goal the development of direct energy conversion (DEC) processes suitable for commercial development. DEC is defined as any fission process that returns usable energy with no intermediate thermal process. This project includes the study of the fission electric cell (FEC). In the FEC, fission fragments exit the fuel element cathode and are collected by the cell anode. Previous work [1] has shown the potential of FECs, with theoretical efficiencies up to 60%. Inspection of this work indicates the need for additional system modeling prior to any conclusions regarding the final FEC reactor configuration. This paper builds on the previous work and outlines the development of models to facilitate design decisions. The models address criticality, design life, reactor configuration, and current-voltage characteristics. In addition, this paper proposes future work to complete the design model. (authors)

King, Donald; Rochau, Gary; Morrow, Charles; Cash, Jamie; Seidel, David; Slutz, Stephen [Sandia National Laboratories (United States)

2002-07-01

390

Analysis of the methane production in thermophilic anaerobic reactors: use of autofluorescence microscopy  

Microsoft Academic Search

Methanogenic activity in thermophilic, anaerobic reactors was determined by comparing the amount of methane generated in single- and two-stage systems with the size of the methanogenic population, as determined by microscopy. The methanogenic activities were 2.71 × 10-9 ml methane cell-1 d-1 and 1.10 × 10-9 ml methane cell-1 d-1 for 10 and 4 days of the hydraulic retention time

R. Solera; L. I. Romero; D. Sales

2001-01-01

391

Fuel assembly for the production of tritium in light water reactors  

DOEpatents

A nuclear fuel assembly is described for producing tritium in a light water moderated reactor. The assembly consists of two intermeshing arrays of subassemblies. The first subassemblies comprise concentric annular elements of an outer containment tube, an annular target element, an annular fuel element, and an inner neutron spectrums shifting rod. The second subassemblies comprise an outer containment tube and an inner rod of either fuel, target, or neutron spectrum shifting neutral.

Cawley, William E. (Richland, WA); Trapp, Turner J. (Richland, WA)

1985-01-01

392

Fuel assembly for the production of tritium in light water reactors  

DOEpatents

A nuclear fuel assembly is described for producing tritium in a light water moderated reactor. The assembly consists of two intermeshing arrays of subassemblies. The first subassemblies comprise concentric annular elements of an outer containment tube, an annular target element, an annular fuel element, and an inner neutron spectrums shifting rod. The second subassemblies comprise an outer containment tube and an inner rod of either fuel, target, or neutron spectrum shifting neutral.

Cawley, W.E.; Trapp, T.J.

1983-06-10

393

Process development of continuous hydrogen production by Enterobacter aerogenes in a packed column reactor  

Microsoft Academic Search

Hydrogen bioproduction from agro-industrial residues by Enterobacter aerogenes in a continuous packed column has been investigated and a complete reactor characterization is presented. Experimental runs carried out at different residence time, liable of interest for industrial application, showed hydrogen yields ranging from 1.36 to 3.02 mmolH2mmolуglucose or, in other words, from 37.5% to 75% of the theoretical hydrogen yield. A

E. Palazzi; B. Fabiano; P. Perego

2000-01-01

394

Continuous production of biogas from dairy manure using an innovative no-mix reactor  

Microsoft Academic Search

A 25 L no-mix anaerobic digester was designed and fabricated. The digester was designed to act as liquid-solid separator.\\u000a The sludges obtained from the bottom of the digester had high nitrogen and ash concentrations while the effluent had no offensive\\u000a odor. The performance of the no-mix digester was compared to that of a continuous stirred tank reactor at two temperatures

A. E. Ghaly; R. M. Ben-Hassan

1989-01-01

395

Production of maltose syrup by bioconversion of cassava starch in an ultrafiltration reactor  

Microsoft Academic Search

The use of an ultrafiltration membrane reactor (UFR) for the bioconversion of cassava starch into maltose was studied. Carbosep membranes with cut-offs of 10, 50 and 150 kDa were used. The 50 kDa cut-off membrane gave the most acceptable results in terms of permeate flux and maltose content. The enzymes Maltogenase and Promozyme (Novo Nordisk) were used to saccharify and

O. Gaouar; N. Zakhia; C. Aymard; G. M. Rios

1998-01-01

396

Characterization of the retained sludge in a down-flow hanging sponge (DHS) reactor with emphasis on its low excess sludge production.  

PubMed

Experiments to characterize retained sludge in a down-flow hanging sponge (DHS) reactor fed with upflow anaerobic sludge blanket (UASB) treated sewage under moderate conditions were conducted. Plenty of oxygen was supplied through the DHS reactor without aeration and the effluent qualities after the reactor were comparable to activated sludge processes. The average excess sludge production rate was 0.09 g SS g(-1) COD removed. The DHS reactor maintained a high sludge concentration of 26.9 g VSS L(-1) sponge, resulting in a low loading rate of 0.032 g COD g(-1) VSS day(-1). The endogenous respiration rate of DHS sludge was comparable to previously reported aerobic sludges. The numbers of microfauna were one order of magnitude greater than those in activated sludge. The results indicated that low excess sludge production was attributable to the high sludge concentration, sufficient oxygen supply, adequate endogenous respiration rate, and a high density and diversity of microfauna. PMID:23567678

Onodera, Takashi; Matsunaga, Kengo; Kubota, Kengo; Taniguchi, Ryoko; Harada, Hideki; Syutsubo, Kazuaki; Okubo, Tsutomu; Uemura, Shigeki; Araki, Nobuo; Yamada, Masayoshi; Yamauchi, Masahito; Yamaguchi, Takashi

2013-03-05

397

Evaluation of injury/illness recordkeeping pilot course taught in Richland, Washington, January 15, 1992  

SciTech Connect

This section summarizes trainee evaluations for the Safety Training Section course, Injury/Illness Recordkeeping which was conducted January 15, at Hanford, in Richland Washington. This class was the first pilot course taught. This class was designed to acquaint attendees with DOE orders 5484.1, 5484.1A, draft 3 and the OSHA regulations found in 29 CFR 1904. This goal was partially achieved; the section pertaining to DOE orders must be improve prior to the next pilot class. Section 1.1 and 1.2 of this report summarize the quantitative course evaluations that trainees provided upon completion of the course. Appendix A provides a transcript of the trainees` written comments. Numeric course ratings were generally positive and show that the course material and instruction were very effective. Written comments supported the positive numeric ratings. The course content and knowledge gained by the trainees exceeded most of the students` expectations of the course. Results from the final examination showed that students gained significant knowledge from the course.

Wright, T.S.

1992-03-01

398

Evaluation of injury/illness recordkeeping pilot course taught in Richland, Washington, January 15, 1992  

SciTech Connect

This section summarizes trainee evaluations for the Safety Training Section course, Injury/Illness Recordkeeping which was conducted January 15, at Hanford, in Richland Washington. This class was the first pilot course taught. This class was designed to acquaint attendees with DOE orders 5484.1, 5484.1A, draft 3 and the OSHA regulations found in 29 CFR 1904. This goal was partially achieved; the section pertaining to DOE orders must be improve prior to the next pilot class. Section 1.1 and 1.2 of this report summarize the quantitative course evaluations that trainees provided upon completion of the course. Appendix A provides a transcript of the trainees' written comments. Numeric course ratings were generally positive and show that the course material and instruction were very effective. Written comments supported the positive numeric ratings. The course content and knowledge gained by the trainees exceeded most of the students' expectations of the course. Results from the final examination showed that students gained significant knowledge from the course.

Wright, T.S.

1992-03-01

399

Inspection of surveillance equipment and activities at DOE Field Office, Richland  

SciTech Connect

The purpose of this inspection was to review surveillance activities by the Department of Energy's (DOE) Field Office, Richland (RL) and contractor employees at the RL Hanford site for efficiency and economy and compliance with laws and regulations. The scope included surveillance activities, procedures, training, types of surveillance equipment, and management controls over the equipment and activities. We also looked at Departmental policies and procedures regarding the equipment and activities. Allegations of illegal surveillance that came to our attention during the course of this inspection were referred to the Department of Justice. As part of our review, inspectors were on-site at RL from February 11, 1991, through March 1, 1991. Follow-up trips to RL were also made in April, May, and June 1991. We also conducted interviews at Albuquerque, Savannah River, and Germantown of former RL employees and RL contractors who were on travel. Officials from DOE's Office of General Counsel (OGC), Office of Security Affairs, and Office of Safeguards and Security (S S) were also interviewed regarding the Department's purchase and possession of wiretapping and eavesdropping devices. We obtained 75 signed sworn statements from 55 individuals during the course of the inspection. 1 fig., 1 tab.

Not Available

1991-09-30

400

Influence of aeration rate and carrier concentration on xylitol production from sugarcane bagasse hydrolyzate in immobilized-cell fluidized bed reactor  

Microsoft Academic Search

A new approach to the biotechnological production of xylitol from sugarcane bagasse using Candida guilliermondii cells immobilized on porous glass in a fluidized bed reactor (FBR) is presented. The influence of aeration rate (AR) and carrier concentration (Cs) on the production process was evaluated. Seven batch fermentation runs were conducted according to a 22 factorial design. The results obtained showed

Júlio C. Santos; Attilio Converti; Walter de Carvalho; Solange I. Mussatto; Silvio S. da Silva

2005-01-01

401

Production of single-walled carbon nanotubes from methane over CoMo\\/MgO nanocatalyst: A comparative study of fixed and fluidized bed reactors  

Microsoft Academic Search

In this study, the performances of fixed and fluidized bed reactors in the production of single-walled carbon nanotubes (SWNTs) have been investigated. In both reactors, single-walled carbon nanotubes were grown by catalytic chemical vapor decomposition (CCVD) of methane over Co-Mo\\/MgO nanocatalyst under two different operating conditions. The synthesized samples were characterized by TEM, TGA and Raman spectroscopy. It is found

Alimorad Rashidi; Roghayeh Lotfi; Ehsaneh Fakhrmosavi; Masoud Zare

2011-01-01

402

Performance evaluation of a mesophilic anaerobic fluidized-bed reactor treating wastewater derived from the production of proteins from extracted sunflower flour  

Microsoft Academic Search

A study of the anaerobic digestion of wastewater derived from the production of protein isolates from extracted sunflower flour was carried out in a laboratory-scale, mesophilic (35°C) fluidized-bed reactor with saponite as bacterial support. Chemical oxygen demand (COD) removal efficiencies in the range of 98.3–80.0% were achieved in the reactor at organic loading rates (OLR) of between 0.6 and 9.3

Rafael Borja; Esther González; Francisco Raposo; Francisco Millán; Antonio Mart??n

2001-01-01

403

Application of a multi-layer packed-bed reactor to citric acid production in solid-state fermentation using Aspergillus niger  

Microsoft Academic Search

Solid-state fermentation, using the fungus Aspergillus niger, has been employed for the production of citric acid from kumara, a starch-containing root crop. A multi-layer packed-bed reactor was designed and operated in an attempt to understand mass and heat transfer during the fermentation. Although only a limited understanding was obtained, the multi-layer packed-bed reactor improved the mass transfer considerably compared with

M. Y. Lu; I. S. Maddox; J. D. Brooks

1998-01-01

404

Fermentative hydrogen production from soybean protein processing wastewater in an anaerobic baffled reactor (ABR) using anaerobic mixed consortia.  

PubMed

Fermentative H(2) production from soybean protein processing wastewater (SPPW) was investigated in a four-compartment anaerobic baffled reactor (ABR) using anaerobic mixed cultures under continuous flow condition in the present study. After being inoculated with aerobic activated sludge and operated at the inoculants of 5.98 gVSS L(-1), COD of 5000 mg L(-1), HRT of 16 h and temperature of (35 ± 1) °C for 22 days, the ABR achieved stable ethanol-type fermentation. The specific hydrogen production rate of anaerobic activated sludge was 165 LH(2)kg MLVSS(-1) day(-1), the substrate conversion rate was 600.83 LH(2)kg COD(-1)and the COD removal efficiency was 44.73% at the stable operation status. The ABR system exhibited a better stability and higher hydrogen yields than continuous stirring tank reactor under the same operational condition. The experimental data documented the feasibility of substrate degradation along with molecular H(2) generation utilizing SPPW as primary carbon source in the ABR system. PMID:21901369

Zhu, Ge-fu; Li, Jian-zheng; Liu, Chao-xiang

2011-09-08

405

Physicochemical properties of cross-linked and acetylated starches and products of their hydrolysis in continuous recycle membrane reactor.  

PubMed

The aim of the present work was to study the physicochemical properties of doubly modified, by cross-linking and acetylating, starches as well as the products of their enzymatic hydrolysis. A two step procedure of hydrolysis, including the batch and membrane reactors, were investigated. The second step of enzymatic processes were carried out in a continuous recycle membrane reactor (CRMR). Three kinds of commercial starches--two preparations of acetylated distarch adipate E1422 of different degrees of cross-linking, as well as one preparation of acetylated distarch phosphate E1414 were examined. It was found that the degree of substitution of acetyl groups in the macromolecules of starch did not influence the effectiveness of hydrolysis. However, the degree of cross-linking with adipate groups slightly decreased the efficiency of processing in the CRMR. Additionally, the relationship between the type of hydrocolloid and its adsorption activity in the air/water and oil/water systems was considered. All obtained derivatives revealed adsorption properties and reduced the surface/interface tension in the air/water and oil/water systems. The efficiency and effectiveness of adsorption of the investigated hydrocolloids were affected by the type of modification as well as the degree of substitution of acetyl groups in the macromolecules of starch. Particle size distributions formed in aqueous solutions for all investigated hydrolyses were determined and compared with results obtained for commercial products. PMID:19734024

Prochaska, Krystyna; Konowa?, Emilia; Sulej-Chojnacka, Joanna; Lewandowicz, Grazyna

2009-08-03

406

CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS/CO2  

SciTech Connect

There are a number of exothermic chemical reactions which might benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. A particularly promising area is production of oxygenated chemicals, such as alcohols and ethers, from synthesis gas, which can be economically produced from coal or biomass. The ebullated bed operation requires that the small-diameter ({approx}1/32 inch) catalyst particles have enough mechanical strength to avoid loss by attrition. However, all of the State Of The Art (SOTA) catalysts and advanced catalysts for the purpose are low in mechanical strength. The patented carbon-coated catalyst technology developed in our laboratory converts catalyst particles with low mechanical strength to strong catalysts suitable for ebullated bed application. This R&D program is concerned with the modification on the mechanical strength of the SOTA and advanced catalysts so that the ebullated bed technology can be utilized to produce valuable oxygenated chemicals from syngas/CO{sub 2} efficiently and economically. The objective of this R&D program is to study the technical and economic feasibility of selective production of high-value oxygenated chemicals from synthesis gas and CO{sub 2} mixed feed in an ebullated bed reactor using carbon-coated catalyst particles.

Peizheng Zhou

2001-10-26

407

CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS/CO2  

SciTech Connect

There are a number of exothermic chemical reactions which might benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. A particularly promising area is production of oxygenated chemicals, such as alcohols and ethers, from synthesis gas, which can be economically produced from coal or biomass. The ebullated bed operation requires that the small-diameter ({approx} 1/32 inch) catalyst particles have enough mechanical strength to avoid loss by attrition. However, all of the State Of The Art (SOTA) catalysts and advanced catalysts for the purpose are low in mechanical strength. The patented carbon-coated catalyst technology developed in our laboratory converts catalyst particles with low mechanical strength to strong catalysts suitable for ebullated bed application. This R&D program is concerned with the modification on the mechanical strength of the SOTA and advanced catalysts so that the ebullated bed technology can be utilized to produce valuable oxygenated chemicals from syngas/CO{sub 2} efficiently and economically. The objective of this R&D program is to study the technical and economic feasibility of selective production of high-value oxygenated chemicals from synthesis gas and CO{sub 2} mixed feed in an ebullated bed reactor using carbon-coated catalyst particles.

Peizheng Zhou

2000-11-17

408

Activation of Canadian coals in a fixed-bed reactor: effect of the particle size on product quality  

SciTech Connect

Three Canadian coals, namely, Bienfait lignite, Montgomery sub-bituminous C, and Coal Valley high volatile bituminous C were activated in a fixed-bed reactor. For each coal, two different sizes of particles in the ranges of 0-1.25 mm (fines) and 1.25-2.5 mm (granules) along with cylindrical pellets of 3.18 mm in diameter and 7{+-}2 mm long were activated. The qualities of the products were determined by measuring iodine and methylene blue numbers, specific Brunauer-Emmett-Teller (BET) surface areas, bulk densities, and ash contents. The specific surface areas and iodine and methylene blue numbers of bituminous coal products were lower than the values obtained with the lignite and sub-bituminous coals, although the product yields were higher. Products obtained from pellets were found to have superior quality compared to that obtained from fines. The ash content of the feed coal influences the quality of the product activated carbon. It was established that a first-order reaction between steam and coal pellets occurred in the process. The activation energies for the process were also determined. 17 refs., 12 figs., 4 tabs.

Ajay K. Dalai; Narayan C. Pradhan; Jian Liu; Amitabha Majumdar; Eric L. Tollefson [University of Saskatchewan, Saskatoon, SK (Canada). Department of Chemical Engineering

2008-07-15

409

Experimental studies and comprehensive reactor modeling of hydrogen production by the catalytic reforming of crude ethanol in a packed bed tubular reactor over a Ni\\/Al 2 O 3 catalyst  

Microsoft Academic Search

A rigorous numerical model was developed to simulate the production of hydrogen from the reforming of crude ethanol in a packed bed tubular reactor (PBTR). The model was based on the coupling of mass and energy balance equations as well as a new kinetic model developed for the process. The simulation results for crude ethanol conversion were found to be

Ahmed Aboudheir; Abayomi Akande; Raphael Idem; Ajay Dalai

2006-01-01

410

A Fisheries Evaluation of the Richland and Toppenish/Satus Canal Fish Screening Facilities, Spring 1986 Annual Report.  

SciTech Connect

The fisheries evaluation phase of diversion screen effectiveness summarizes the results of work at the Richland and Toppenish/Satus Fish screening facilities (Richland Screens and Toppenish/Satus Screens) during 1986. More than 10,000 steelhead, Salmo gairdneri, and chinook salmon, Oncorhynchus tshawytscha, were released at the screen diversions. At the Richland Screens, 61% of the released steelhead were recovered and 1.1% were descaled; 93% of the spring chinook salmon were recovered and less than 1% were descaled. At the Toppenish/Satus Screens, only steelhead were evaluated for descaling; 88.9% were recovered and 23.9% were descaled. Only steelhead were evaluated because the Yakima River fisheries managers did not expect any other smolts to occur in Toppenish Creek. Because of the acclimation conditions and the amount of time the fish had to be held before testing, some of the test population were descaled during holding and transportation. The 23.9% descaling for the test fish was compared to 26.4% for the controls.

Neitzel, D.A.; Abernethy, C. Scott; Lusty, E. William

1987-05-01

411

Microstructured Reactors for Development and Production in Pharmaceutical and Fine Chemistry  

Microsoft Academic Search

The true potential of microprocess technology for process\\u000a \\u0009 intensification is not yet fully clear and needs to be actively\\u000a \\u0009 explored, although more and more industrial case stories provide\\u000a \\u0009 information. This paper uses a short-cut cost analysis to\\u000a \\u0009 show the major cost portions for processes conducted by\\u000a \\u0009 microstructured reactors. This leads to predicting novel chemical\\u000a \\u0009 protocol conditions, which are tailored for microprocess

V. Hessel; P. Löb; U. Krtschil; H. Löwe

2007-01-01

412

Production of cyclodextrins in a fluidized-bed reactor using cyclodextrin-glycosyl-transferase  

Microsoft Academic Search

Cyclodextrin-glycosyl-transferase (EC2.4.1.19), produced by Wacker (Munich, Germany), was purified by biospecific affinity\\u000a chromatography with ?-cyclodextrin (?-CD) as ligand, and immobilized into controlled pore silica particles (0.42 mm). This\\u000a immobilized enzyme (IE) had 4.7 mg of protein\\/g of support and a specific activity of 8.6 ?mol of ?-CD\\/(min·gIF) at 50°C, pH 8.0. It was used in a fluidized-bed reactor (FBR) at

Paulo W. Tardioli; Gisella M. Zanin; Flávio F. de Moraes

2000-01-01

413

Method for fabricating wrought components for high-temperature gas-cooled reactors and product  

DOEpatents

A method and alloys for fabricating wrought components of a high-temperature gas-cooled reactor are disclosed. These wrought, nickel-based alloys, which exhibit strength and excellent resistance to carburization at elevated temperatures, include aluminum and titanium in amounts and ratios to promote the growth of carburization resistant films while preserving the wrought character of the alloys. These alloys also include substantial amounts of molybdenum and/or tungsten as solid-solution strengtheners. Chromium may be included in concentrations less than 10% to assist in fabrication. Minor amounts of carbon and one or more carbide-forming metals also contribute to high-temperature strength.

Thompson, Larry D. (San Diego, CA); Johnson, Jr., William R. (San Diego, CA)

1985-01-01

414

Nuclear track membranes: Production in nuclear reactors and prospects of application  

SciTech Connect

Nuclear track membranes are produced by a physico-chemical treatment of polymeric films exposed to fission fragments in nuclear reactors or to heavy ion beams. Heavy charged particles form in the solids along their trajectories regions of high ionization density where polymer destruction takes place. Selective dissolution of damaged material converts the initial film into a microfiltration membrane with cylindrical through pores. The main feature of nuclear membranes are a small thickness and uniformity of pore size. The qualities of the nuclear membranes promise good prospects for applications in many areas.

Fursov, B.I.; Kryuchkov, E.A.; Mironov, N.N. [and others

1993-12-31

415

Advanced Resources for Catalysis Science: Workshop Results. Recommendations for a National Catalysis Research Institute. Held in Richland, Washington on September 21-22, 2004.  

National Technical Information Service (NTIS)

Twenty-seven experts-representing a broad spectrum-from national laboratories, industry, and universities participated in the Advanced Resources for Catalysis Science Workshop held at Pacific Northwest National Laboratory, Richland, Washington, September ...

D. Ray C. Peden

2004-01-01

416

A pilot plant scale Continuous Stirred Reactor\\/Separator for the production of ethanol from corn grits\\/starch and biomass streams. [Quarterly progress report, May 1, 1994August 1, 1994  

Microsoft Academic Search

This project seeks to develop and demonstrate an improved reactor for the production of ethanol from starch and ligno-cellulosic streams. Bio-Process Innovations holds a patent on this reactor technology, and is directing the project. A Continuous Stirred Reactor Separator (CSRS) is being built on a pilot plant scale for testing at a small Iowa ethanol plant (Permeate Refining) while bench

1994-01-01

417

Use of Glucose Oxidase in a Membrane Reactor for Gluconic Acid Production  

NASA Astrophysics Data System (ADS)

This article aims at the evaluation of the catalytic performance of glucose oxidase (GO) (EC.1.1.3.4) for the glucose/gluconic acid conversion in the ultrafiltration cell type membrane reactor (MB-CSTR). The reactor was coupled with a Millipore ultrafiltration-membrane (cutoff of 100 kDa) and operated for 24 h under agitation of 100 rpm, pH 5.5, and 30°C. The experimental conditions varied were the glucose concentration (2.5, 5.0, 10.0, 20.0, and 40.0 mM), the feeding rate (0.5, 1.0, 3.0, and 6.0/h), dissolved oxygen (8.0 and 16.0 mg/L), GO concentration (2.5, 5.0, 10.0, and 20.0 UGO/mL), and the glucose oxidase/catalase activity ratio (UGO/UCAT)(1?0, 1?10, 1?20, and 1?30). A conversion yield of 80% and specific reaction rate of 40×10-4 mmol/h·UGO were attained when the process was carried out under the following conditions: D=3.0/h, dissolved oxygen=16.0 mg/L, [G]=40 mM, and (UGO/UCAT)=1?20. A simplified model for explaining the inhibition of GO activity by hydrogen peroxide, formed during the glucose/gluconic acid conversion, was presented.

Das Neves, Luiz Carlos Martins; Vitolo, Michele

418

Inspection indications, stress corrosion cracks and repair of process piping in nuclear materials production reactors  

SciTech Connect

Ultrasonic inspection of Schedule 40 Type 304 stainless steel piping in the process water system of the Savannah River Site reactors has provided indications of discontinuities in less than 10% of the weld heat affected zones. Pipe sections containing significant indications are replaced with Type 304L components. Post removal metallurgical evaluation showed that the indications resulted from stress corrosion cracking in weld heat-affected zones and that the overall weld quality was excellent. The evaluation also revealed weld fusion zone discontinuities such as incomplete penetration, incomplete fusion, inclusions, underfill at weld roots and hot cracks. Service induced extension of these discontinuities was generally not significant although stress corrosion cracking in one weld fusion zone was noted. One set of UT indications was caused by metallurgical discontinuities at the fusion boundary of an extra weld. This extra weld, not apparent on the outer pipe surface, was slightly overlapping and approximately parallel to the weld being inspected. This extra weld was made during a pipe repair, probably associated with initial construction processes. The two nearly parallel welds made accurate assessment of the UT signal difficult. The implications of these observations to the inspection and repair of process water systems of nuclear reactors is discussed.

Louthan, M.R. Jr.; West, S.L.; Nelson, D.Z.

1991-01-01

419

Modeling of a Multitube High-Temperature Solar Thermochemical Reactor for Hydrogen Production  

SciTech Connect

A solar reactor consisting of a cavity-receiver containing an array of tubular absorbers is considered for performing the ZnO-dissociation as part of a two-step H{sub 2}O-splitting thermochemical cycle using concentrated solar energy. The continuity, momentum, and energy governing equations that couple the rate of heat transfer to the Arrhenius-type reaction kinetics are formulated for an absorbing-emitting-scattering particulate media and numerically solved using a computational fluid dynamics code. Parametric simulations were carried out to examine the influence of the solar flux concentration ratio (3000-6000 suns), number of tubes (1-10), ZnO mass flow rate (2-20 g/min per tube), and ZnO particle size (0.06-1 {mu}m) on the reactor's performance. The reaction extent reaches completion within 1 s residence time at above 2000 K, yielding a solar-to-chemical energy conversion efficiency of up to 29%.

Haussener, S.; Hirsch, D.; Perkins, C.; Weimer, A.; Lewandowski, A.; Steinfeld, A.

2009-05-01

420

Inspection indications, stress corrosion cracks and repair of process piping in nuclear materials production reactors  

SciTech Connect

Ultrasonic inspection of Schedule 40 Type 304 stainless steel piping in the process water system of the Savannah River Site reactors has provided indications of discontinuities in less than 10% of the weld heat affected zones. Pipe sections containing significant indications are replaced with Type 304L components. Post removal metallurgical evaluation showed that the indications resulted from stress corrosion cracking in weld heat-affected zones and that the overall weld quality was excellent. The evaluation also revealed weld fusion zone discontinuities such as incomplete penetration, incomplete fusion, inclusions, underfill at weld roots and hot cracks. Service induced extension of these discontinuities was generally not significant although stress corrosion cracking in one weld fusion zone was noted. One set of UT indications was caused by metallurgical discontinuities at the fusion boundary of an extra weld. This extra weld, not apparent on the outer pipe surface, was slightly overlapping and approximately parallel to the weld being inspected. This extra weld was made during a pipe repair, probably associated with initial construction processes. The two nearly parallel welds made accurate assessment of the UT signal difficult. The implications of these observations to the inspection and repair of process water systems of nuclear reactors is discussed.

Louthan, M.R. Jr.; West, S.L.; Nelson, D.Z.

1991-12-31

421

The Ongoing Impact of the U.S. Fast Reactor Integral Experiments Program  

SciTech Connect

The creation of a large database of integral fast reactor physics experiments advanced nuclear science and technology in ways that were unachievable by less capital intensive and operationally challenging approaches. They enabled the compilation of integral physics benchmark data, validated (or not) analytical methods, and provided assurance of future rector designs The integral experiments performed at Argonne National Laboratory (ANL) represent decades of research performed to support fast reactor design and our understanding of neutronics behavior and reactor physics measurements. Experiments began in 1955 with the Zero Power Reactor No. 3 (ZPR-3) and terminated with the Zero Power Physics Reactor (ZPPR, originally the Zero Power Plutonium Reactor) in 1990 at the former ANL-West site in Idaho, which is now part of the Idaho National Laboratory (INL). Two additional critical assemblies, ZPR-6 and ZPR-9, operated at the ANL-East site in Illinois. A total of 128 fast reactor assemblies were constructed with these facilities [1]. The infrastructure and measurement capabilities are too expensive to be replicated in the modern era, making the integral database invaluable as the world pushes ahead with development of liquid metal cooled reactors.

John D. Bess; Michael A. Pope; Harold F. McFarlane

2012-11-01

422

Environmental restoration and waste management site-specific plan for Richland Operations Office. [Contains glossary  

SciTech Connect

This document was prepared to implement and support the US Department of Energy-Headquarters (DOE-HQ) national plan. The national plan, entitled Environmental Restoration and Waste Management Five-Year Plan (DOE 1990b) (hereinafter referred to as the DOE-HQ Five-Year Plan) is the cornerstone of the US Department of Energy's (DOE) long-term strategy in environmental restoration and waste management. The DOE-HQ Five-Year Plan addresses overall philosophy and environmental and waste-related activities under the responsibilities of the DOE Office of Environmental Restoration and Waste Management. The plan also reaffirms DOE-HQ goals to bring its nuclear sites into environmental compliance in cooperation with its regulators and the public, and to clean up and restore the environment by 2019 (the commitment for the Hanford Site is for one year sooner, or 2018). This document is part of the site-specific plan for the US Department of Energy-Richland Operations Office (DOE-RL). It is the first revision of the original plan, which was dated December 1989 (DOE-RL 1989a). This document is a companion document to the Overview of the Hanford Cleanup Five-Year Plan (DOE-RL 1989d) and The Hanford Site Environmental Restoration and Waste Management Five-Year Plan Activity Data Sheets (DOE-RL 1991). Although there are three documents that make up the complete DOE-RL plan, this detailed information volume was prepared so it could be used as a standalone document. 71 refs., 40 figs., 28 tabs.

Not Available

1991-09-01

423

Environmental assessment of SP-100 ground engineering system test site: Hanford Site, Richland, Washington  

SciTech Connect

The US Department of Energy (DOE) proposes to modify an existing reactor containment building (decommissioned Plutonium Recycle Test Reactor (PRTR) 309 Building) to provide ground test capability for the prototype SP-100 reactor. The 309 Building (Figure 1.1) is located in the 300 Area on the Hanford Site in Washington State. The National Environmental Policy Act (NEPA) requires that Federal agencies assess the potential impacts that their actions may have on the environment. This Environmental Assessment describes the consideration given to environmental impacts during reactor concept and test site selection, examines the environmental effects of the DOE proposal to ground test the nuclear subsystem, describes alternatives to the proposed action, and examines radiological risks of potential SP-100 use in space. 73 refs., 19 figs., 7 tabs.

Not Available

1988-12-01

424

Separation of fission products from spent pressurized water reactor fuels by anion exchange and extraction chromatography for inductively coupled plasma atomic emission spectrometric analysis  

Microsoft Academic Search

A study has been carried out on the separation of fission products from spent pressurized water reactor (PWR) fuels and their quantitative determination using inductively coupled plasma atomic emission spectrometry (ICP-AES). Plutonium and uranium were separated from fission products using anion exchange and tri-n-butylphosphate (TBP) extraction chromatography, respectively. Americium was separated and fission products such as Sr, Ba, Cd, La,

Chang Heon Lee; Moo Yul Suh; Kwang Soon Choi; Jung Suk Kim; Byong Chul Song; Kwang Yong Jee; Won Ho Kim

2001-01-01

425

Bacterial cellulose production under oxygen-enriched air at different fructose concentrations in a 50-liter, internal-loop airlift reactor  

Microsoft Academic Search

Bacterial cellulose (BC) production by Acetobacter xylinum subsp. sucrofermentans BPR2001 was carried out in a 50-l internal-loop airlift reactor in air at an initial fructose concentration of 40 g\\/l. The BC production rate was 0.059 g\\/l per h. When oxygen-enriched air was supplied instead of air, the BC production rate increased to 0.093 g\\/l per h, and the BC yield

Y. Chao; Y. Sugano; M. Shoda

2001-01-01

426

Effects of fed-batch fermentation and pH profiles on nisin production in suspended-cell and biofilm reactors  

Microsoft Academic Search

A biofilm reactor not only shortens the lag phase of nisin production, but also enhances nisin production when combined with an appropriate pH profile. Due to the substrate inhibition that takes place at high levels of carbon source, fed-batch fermentation was proposed as a better alternative for nisin production. In this study, the combined effects of fed-batch fermentation and various

Thunyarat Pongtharangkul; Ali Demirci

2006-01-01

427

Production optimization with operating constraints for a fed-batch reactor with DMC predictive control  

Microsoft Academic Search

This work presents a production optimization approach with operating constraints applied to a fed-batch penicillin process with a DMC predictive controller. A deterministic and non-structured mathematical model of the fed-batch penicillin production process solved by a fourth order variable step Runge–Kutta–Gill algorithm type simulated the system. The production process optimization has been performed through the manipulation of the initial cell

J. A. D. Rodrigues; R. Maciel Filho

1999-01-01

428

Production of middle distillate in a dual-bed reactor from synthesis gas through wax cracking: Effect of acid property of Pd-loaded solid acid catalysts on the wax conversion and middle distillate selectivity  

Microsoft Academic Search

Selective production of middle distillate (C10–C20) from synthesis gas (CO+H2) was carried out in a dual-bed reactor. Co-based catalysts were used in the first-bed reactor to produce wax (C21+) from synthesis gas, and Pd-loaded solid acid catalysts were used in the second-bed reactor to produce middle distillate from wax through hydrocracking. Co\\/TiO2 catalyst in the first-bed reactor produced more than

Kyung Min Cho; Sunyoung Park; Jeong Gil Seo; Min Hye Youn; Sung-Hyeon Baeck; Ki-Won Jun; Jin Suk Chung; In Kyu Song

2008-01-01

429

Continuous Production of Lipase-Catalyzed Biodiesel in a Packed-Bed Reactor: Optimization and Enzyme Reuse Study  

PubMed Central

An optimal continuous production of biodiesel by methanolysis of soybean oil in a packed-bed reactor was developed using immobilized lipase (Novozym 435) as a catalyst in a tert-butanol solvent system. Response surface methodology (RSM) and Box-Behnken design were employed to evaluate the effects of reaction temperature, flow rate, and substrate molar ratio on the molar conversion of biodiesel. The results showed that flow rate and temperature have significant effects on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions were as follows: flow rate 0.1?mL/min, temperature 52.1°C, and substrate molar ratio 1?:?4. The predicted and experimental values of molar conversion were 83.31 ± 2.07% and 82.81 ± .98%, respectively. Furthermore, the continuous process over 30 days showed no appreciable decrease in the molar conversion. The paper demonstrates the applicability of using immobilized lipase and a packed-bed reactor for continuous biodiesel synthesis.

Chen, Hsiao-Ching; Ju, Hen-Yi; Wu, Tsung-Ta; Liu, Yung-Chuan; Lee, Chih-Chen; Chang, Cheng; Chung, Yi-Lin; Shieh, Chwen-Jen

2011-01-01

430

10. Floor Layout of Thermal Hydraulics Laboratory, from The Thermal ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. Floor Layout of Thermal Hydraulics Laboratory, from The Thermal Hydraulics Laboratory at Hanford. General Electric Company, Hanford Atomic Products Operation, Richland, Washington, 1961. - D-Reactor Complex, Deaeration Plant-Refrigeration Buildings, Area 100-D, Richland, Benton County, WA

431

The economic and community impacts of closing Hanford's N Reactor and nuclear materials production facilities  

Microsoft Academic Search

This study discusses the negative economic impact on local cities and counties and the State of Washington of a permanent closure of nuclear materials production at the Hanford Site, located in the southeastern part of the state. The loss of nuclear materials production, the largest and most important of the five Department of Energy (DOE) missions at Hanford, could occur

M. J. Scott; D. B. Belzer; R. J. Nesse; R. W. Schultz; P. A. Stokowski; D. C. Clark

1987-01-01

432

Licensing for tritium production in a commercial light water reactor: A utility view  

Microsoft Academic Search

In a December 1995 Record of Decision for the Final Programmatic Environmental Impact Statement for Tritium Supply and Recycling, the US Department of Energy (DOE) decided to pursue a dual-track approach to determine the preferred option for future production of tritium for the nuclear weapons stockpile. The two options to be pursued were (a) the Accelerator Production of Tritium and

J. S. Chardos; G. C. Sorensen; L. W. Erickson

2000-01-01

433

PRODUCTION OF ACETONE BUTANOL (AB) FROM AGRICULTURAL RESIDUES USING CLOSTRIDIUM ACETOBUTYLICUM IN BATCH REACTORS COUPLED WITH PRODUCT RECOVERY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Substrate cost is one of the most important factors that affects price of butanol production by fermentation. For this reason, use of economically available substrates such as agricultural residues should be investigated. Hence, wheat straw (WS) was chosen for the present studies for acetone butan...

434

Design and demonstration of an immobilized-cell fluidized-bed reactor for the efficient production of ethanol  

SciTech Connect

Initial studies have been carried out using a 4 inch ID fluidized bed reactor (FBR). This medium scale FBR was designed for scale-up. Present performance was compared with results from experiments using smaller FBRs. On-line and off-line measurement systems are also described. Zymomonas mobilis was immobilized in {kappa}-carrageenan at cell loadings of 15--50 g (dry weight) L{sup {minus}1}. The system is designed for determining optimal operation with high conversion and productivity for a variety of conditions including feedstocks, temperature, flow rate, and column sizes (from 2 to 5 meters tall). The demonstration used non-sterile feedstocks containing either industrial (light steep water) or synthetic nutrients and dextrose.

Webb, O.F.; Scott, T.C.; Davison, B.H.; Scott, C.D.

1994-06-01

435

Arrival time and magnitude of airborne fission products from the Fukushima, Japan, reactor incident as measured in Seattle, WA, USA.  

PubMed

We report results of air monitoring started due to the recent natural catastrophe on 11 March 2011 in Japan and the severe ensuing damage to the Fukushima Dai-ichi nuclear reactor complex. On 17-18 March 2011, we registered the first arrival of the airborne fission products (131)I, (132)I, (132)Te, (134)Cs, and (137)Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. We measured the evolution of the activities over a period of 23 days at the end of which the activities had mostly fallen below our detection limit. The highest detected activity from radionuclides attached to particulate matter amounted to 4.4 ± 1.3 mBq m(-3) of (131)I on 19-20 March. PMID:21719167

Leon, J Diaz; Jaffe, D A; Kaspar, J; Knecht, A; Miller, M L; Robertson, R G H; Schubert, A G

2011-06-29

436

Development of a phenomena identification and ranking table for thermal-hydraulic phenomena during a double-ended guillotine break LOCA in an SRS production reactor  

SciTech Connect

A rising level of scrutiny is being directed toward the Savannah River Site (SRS) production reactors. Improved calculational capabilities are being developed to provide a best estimate analytical process to determine the safe operating margins of the reactors. The Code Scaling, Applicability, and Uncertainty (CSAU) methodology, developed by the US Nuclear Regulatory Commission to support best estimate simulations, is being applied to the best estimate limits analysis for the SRS production reactors. One of the foundational parts of the method is the identification and ranking of all the processes that occur during the specific limiting scenario. The phenomena ranking is done according to their importance to safety criteria during the transient and is used to focus the uncertainty analysis on a sufficient, yet cost effective scope of work. This report documents the thermal-hydraulic phenomena that occur during a limiting break in an SRS production reactor and their importance to the uncertainty in simulations of the reactor behavior. 9 refs., 14 figs., 10 tabs.

Hanson, R.G.; Ortiz, M.G.; Bolander, M.A.; Wilson, G.E.

1989-07-01

437

Removal of estrogenic compounds from filtered secondary wastewater effluent in a continuous enzymatic membrane reactor. Identification of biotransformation products.  

PubMed

In the present study, a novel and efficient technology based on the use of an oxidative enzyme was developed to perform the continuous removal of estrogenic compounds from polluted wastewaters. A 2 L enzymatic membrane reactor (EMR) was successfully operated for 100 h with minimal requirements of laccase for the transformation of estrone (E1), 17?-estradiol (E2), and 17?-ethinylestradiol (EE2)from both buffer solution and real wastewater (filtered secondary effluent). When the experiments were performed at high and low concentrations of the target compounds, 4 mg/L and 100 ?g/L, not only high removal yields (80-100%) but also outstanding reduction of estrogenicity (about 84-95%) were attained. When the EMR was applied for the treatment of municipal wastewaters with real environmental concentrations of the different compounds (0.29-1.52 ng/L), excellent results were also achieved indicating the high efficiency and potential of the enzymatic reactor system. A second goal of this study relied on the identification of the transformation products to elucidate the catalytic mechanism of estrogens' transformation by laccase. The formation of dimers and trimers of E1, E2, and EE2, as well as the decomposition of E2 into E1 by laccase-catalyzed treatment, has been demonstrated by liquid chromatography atmospheric pressure chemical ionization (LC-APCI) analysis and confirmed by determination of accurate masses through liquid chromatography electrospray time-of-flight mass spectrometry (LC-ESI-TOF). Dimeric products of E2 and EE2 were found even when operating at environmental concentrations. Moreover, the reaction pathways of laccase-catalyzed transformation of E2 were proposed. PMID:23544499

Lloret, Lucia; Eibes, Gemma; Moreira, M Teresa; Feijoo, Gumersindo; Lema, Juan M

2013-04-09

438

Biofuels from Pyrolysis: Catalytic Biocrude Production in a Novel, Short-Contact Time Reactor  

SciTech Connect

Broad Funding Opportunity Announcement Project: RTI is developing a new pyrolysis process to convert second-generation biomass into biofuels in one simple step. Pyrolysis is the decomposition of substances by heating—the same process used to render wood into charcoal, caramelize sugar, and dry roast coffee and beans. RTI’s catalytic biomass pyrolysis differs from conventional flash pyrolysis in that its end product contains less oxygen, metals, and nitrogen—all of which contribute to corrosion, instability, and inefficiency in the fuel-production process. This technology is expected to easily integrate into the existing domestic petroleum refining infrastructure, making it an economically attractive option for biofuels production.

None

2010-01-01

439

Continuous ethanol production from nonsterilized carob pod extract by immobilized Saccharomyces cerevisiae on mineral kissiris using a two-reactor system  

SciTech Connect

The continuous production of ethanol from nonsterilized carob pod extract by immobilized Saccharomyces cerevisiae on mineral kissiris using one- and two-reactor systems has been investigated. A maximum ethanol productivity of 9.6 g/L/h was obtained at an initial sugar concentration of 200 g/L and D = 0.4 h{sup -1} with 68% of theoretical yield and 34% of sugar utilization using the one-reactor system. At S{sub 0} = 200 g/L, D = 0.05 h{sup -1}, 83% of theoretical yield, and 64% of sugar utilization, an ethanol productivity of 2.6 g/L/h was achieved. In the two-reactor system, a maximum ethanol productivity of 11.4 g/L/h was obtained at S{sub 0} = 200 g/L and D = 0.4 h{sup -1} with 68.5% of theoretical yield and 41.5% of sugar utilization. The two-reactor system was operated at a constant dilution rate of 0.3 h{sup -1} for 60 d without loss of the original immobilized yeast activity. In this case, the average ethanol productivity, ethanol yield (% of theoretical), and sugar utilization were 10.7 g/L/h, 71.5%, and 48%, respectively. 18 refs., 3 figs.

Roukas, T. [Aristotle Univ. of Thessaloniki (Greece)

1996-06-01

440

Optimization of continuous hydrogen production from co-fermenting molasses with liquid swine manure in an anaerobic sequencing batch reactor.  

PubMed

This study investigated and optimized the operational conditions for continuous hydrogen production from sugar beet molasses, co-fermented with liquid swine manure in an anaerobic sequencing batch reactor. Results indicated that pH, HRT and total solids content in the swine manure (TS) had significant impact on all the responses such as biogas production rate (BPR), hydrogen content (HC), hydrogen production rate (HPR), and hydrogen yield (HY), although the highest level of each response was achieved at different combination of the three variables. The maximum BPR, HC, HPR and HY of 32.21 L/d, 30.51%, 2.23 L/d/L and 1.57 mol-H2/mol-sugar were estimated at the optimal pH, HRT, and TS of 5.55, 15.78 h, and 0.71% for BPR; 5.22, 12.04, and 0.69 for HC; 5.32, 15.62, and 0.78% for HPR; and 5.36, 17.56, and 0.74% for HY, respectively. Good linear relationships of the predicted and tested results for all the parameters were observed. PMID:23567702

Wu, Xiao; Lin, Hongjian; Zhu, Jun

2013-03-07

441

Continuous Recycle Enzymatic Membrane Reactor System for In-situ Production of Pure and Sterile Glucose Solution  

NASA Astrophysics Data System (ADS)

In this study, an efficient Continuous Recycle Enzymatic Membrane Reactor (CREMR) system for production of in-situ glucose solution was developed and the Simultaneous Gelatinization, Liquefaction and Saccharification (SGLS) carried out at temperatures below 60°C, is proposed to replace the conventional starch hydrolysis. Using a 30 kD polysulfone hollow fibre membrane and 10% (w/w) tapioca starch concentration, it is found that during the steady state continuous operation, the SGLS process in the CREMR at temperatures of 55 and 60°C and trans-membrane pressures of 0.5 and 1 bar has produced a steady state glucose concentration in the permeate stream as high as 64 g L-1 over a period of eight hours operation. The glucose solution obtained is of high purity greater than 99.9% and sterile, hence can be utilised as intravenous dripping solution and other medical products without post-treatments. In addition, the CREMR system is also relatively easy to scale-up, has a smaller footprint c.f. conventional systems, thus allowing in-situ production.

Sarbatly, Rosalam; Krishnaiah, Duduku; England, Richard

442

Retrofit Russian research reactors  

Microsoft Academic Search

A likely source for enriched uranium for production of a gun-type bomb might be a research reactor. A state or terrorist organization would find the technical process for separating uranium from the reactor fuel plates is simple and well-published. An unguarded research reactor could be found in the former Soviet Union. Russia and the former republics have seen an increasing

Mabe

1993-01-01

443

High solids fermentation reactor  

DOEpatents

A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

Wyman, Charles E. (Lakewood, CO); Grohmann, Karel (Littleton, CO); Himmel, Michael E. (Littleton, CO); Richard, Christopher J. (Lakewood, CO)

1993-01-01

444

Reconstruction of Radial Fission-Product Distributions in Reactor Fuels from a Small Number of Projections.  

National Technical Information Service (NTIS)

Four mathematical techniques for reconstruction of the radial two-dimensional distribution of fission products using projections obtained by nondestructive gamma scanning were evaluated. Reconstruction of a picture from a finite set of projections is math...

B. K. Barnes J. R. Phillips M. L. Barnes

1981-01-01

445

Ni-Si Alloys for the S-I Reactor-Hydrogen Production Process Interface  

SciTech Connect

The overall goal of this project was to develop Ni-Si alloys for use in vessels to contain hot, pressurized sulfuric acid. The application was to be in the decomposition loop of the thermochemical cycle for production of hydrogen.

Joseph W. Newkirk; Richard K. Brow

2010-01-21

446

NiSi Alloys for the SI Reactor-Hydrogen Production Process Interface  

Microsoft Academic Search

The overall goal of this project was to develop Ni-Si alloys for use in vessels to contain hot, pressurized sulfuric acid. The application was to be in the decomposition loop of the thermochemical cycle for production of hydrogen.

Joseph W. Newkirk; Richard K. Brow

2010-01-01

447

Fermentative hydrogen production from liquid swine manure with glucose supplement using an anaerobic sequencing batch reactor  

Microsoft Academic Search

The idea of coupling renewable energy production and agricultural waste management inspired this thesis. The production of an important future fuel---hydrogen gas---from high strength waste stream-liquid swine manure---using anaerobic treatment processes makes the most sustainable sense for both wastewater utilization and energy generation. The objectives of this thesis were to develop a fermentation process for converting liquid swine manure to

Xiao Wu

2009-01-01

448

Optimization of a flat plate glass reactor for mass production of Nannochloropsis sp. outdoors  

Microsoft Academic Search

The relationships between areal (g m?2 per day) and volumetric (g l?1 per day) productivity of Nannochloropsis sp. as affected by the light-path (ranging from 1.3 to 17.0 cm) of a vertical flat plate glass photobioreactor were elucidated. In general, the shorter the length of the light-path (LP), the smaller the areal volume and the higher the volumetric productivity. The