FLAMMABLE GAS TECHNICAL BASIS DOCUMENT

Energy Technology Data Exchange (ETDEWEB)

KRIPPS, L.J.

2005-03-03

This document describes the qualitative evaluation of frequency and consequences for DST and SST representative flammable gas accidents and associated hazardous conditions without controls. The evaluation indicated that safety-significant structures, systems and components (SSCs) and/or technical safety requirements (TSRs) were required to prevent or mitigate flammable gas accidents. Discussion on the resulting control decisions is included. This technical basis document was developed to support WP-13033, Tank Farms Documented Safety Analysis (DSA), and describes the risk binning process for the flammable gas representative accidents and associated represented hazardous conditions. The purpose of the risk binning process is to determine the need for safety-significant structures, systems, and components (SSC) and technical safety requirement (TSR)-level controls for a given representative accident or represented hazardous condition based on an evaluation of the event frequency and consequence.

Flammable Gas Safety Self-Study 52827

Energy Technology Data Exchange (ETDEWEB)

Glass, George [Los Alamos National Laboratory

2016-03-17

This course, Flammable Gas Safety Self-Study (COURSE 52827), presents an overview of the hazards and controls associated with commonly used, compressed flammable gases at Los Alamos National Laboratory (LANL).

Steady-State Flammable Gas Release Rate Calculation And Lower Flammability Level Evaluation For Hanford Tank Waste

International Nuclear Information System (INIS)

Meacham, J.E.

2008-01-01

This report assesses the steady state flammability level under off normal ventilation conditions in the tank headspace for 28 double-shell tanks (DST) and 149 single shell-tanks (SST) at the Hanford Site. Flammability was calculated using estimated gas release rates, Le Chatelier's rule, and lower flammability limits of fuels in an air mixture. This revision updates the hydrogen generation rate input data for al1 177 tanks using waste composition information from the Best Basis Inventory Detail Report (data effective as of August 4,2008). Assuming only barometric breathing, the shortest time to reach 25% of the lower flammability limit is 13 days for DSTs (i.e., tank 241-AZ-102) and 36 days for SSTs (i.e., tank 241-B-203). Assuming zero ventilation, the shortest time to reach 25% of the lower flammability limit is 12 days for DSTs (i.e., tank 241-AZ-102) and 34 days for SSTs (i.e., tank 241-B-203).

Steady-State Flammable Gas Release Rate Calculation And Lower Flammability Level Evaluation For Hanford Tank Waste

International Nuclear Information System (INIS)

Meacham, J.E.

2009-01-01

This report assesses the steady state flammability level under off normal ventilation conditions in the tank headspace for 28 double-shell tanks (DST) and 149 single shell-tanks (SST) at the Hanford Site. Flammability was calculated using estimated gas release rates, Le Chatelier's rule, and lower flammability limits of fuels in an air mixture. This revision updates the hydrogen generation rate input data for all 177 tanks using waste composition information from the Best Basis Inventory Detail Report (data effective as of August 4,2008). Assuming only barometric breathing, the shortest time to reach 25% of the lower flammability limit is 11 days for DSTs (i.e., tank 241-AZ-10l) and 36 days for SSTs (i.e., tank 241-B-203). Assuming zero ventilation, the shortest time to reach 25% of the lower flammability limit is 10 days for DSTs (i.e., tank 241-AZ-101) and 34 days for SSTs (i.e., tank 241-B-203).

Operational experience in mitigating flammable gas releases from Hanford Site Tank 241-SY-101

International Nuclear Information System (INIS)

Lentsch, J.W.; Babad, H.; Kirch, N.W.

1995-01-01

Flammable gases consisting of hydrogen, nitrous oxide, ammonia, and methane are periodically released from Hanford Site waste tank 241-SY-101 at concentrations above the flammable limit. A large mixer pump installed in the tank in 1993 has effectively mitigated this problem by continuously releasing small amounts of the flammable gases at the rate they are generated. Tank 241-SY-101 is also equipped with multiple high-sensitivity gas monitoring systems and level detection systems to measure the quantity of gas that is retained in and released from the waste

Hazard assessments of double-shell flammable gas tanks

International Nuclear Information System (INIS)

Fox, G.L.; Stepnewski, D.D.

1994-01-01

This report is the fourth in a series of hazard assessments performed on the double-shell flammable gas watch list tanks. This report focuses on hazards associated with the double-shell watch list tanks (101-AW, 103-AN, 104-AN, and 105-AN). While a similar assessment has already been performed for tank 103-SY, it is also included here to incorporate a more representative slurry gas mixture and provide a consistent basis for comparing results for all the flammable gas tanks. This report is intended to provide an in-depth assessment by considering the details of the gas release event and slurry gas mixing as the gas is released from the waste. The consequences of postulated gas ignition are evaluated using a plume burn model and updated ignition frequency predictions. Tank pressurization which results from a gas burn, along with the structural response, is also considered. The report is intended to support the safety basis for work activities in flammable gas tanks by showing margins to safety limits that are available in the design and procedures

Quality Assurance Program Plan for TRUPACT-II Gas Generation Test Program

International Nuclear Information System (INIS)

2002-01-01

The Gas Generation Test Program (GGTP), referred to as the Program, is designed to establish the concentration of flammable gases and/or gas generation rates in a test category waste container intended for shipment in the Transuranic Package Transporter-II (TRUPACT-II). The phrase 'gas generationtesting' shall refer to any activity that establishes the flammable gas concentration or the flammable gas generation rate. This includes, but is not limited to, measurements performed directly on waste containers or during tests performed on waste containers. This Quality Assurance Program Plan (QAPP) documents the quality assurance (QA) and quality control (QC) requirements that apply to the Program. The TRUPACT-II requirements and technical bases for allowable flammable gas concentration and gas generation rates are described in the TRUPACT-II Authorized Methods for Payload Control (TRAMPAC).

A summary description of the flammable gas tank safety program

International Nuclear Information System (INIS)

Johnson, G.D.; Sherwood, D.J.

1994-10-01

Radioactive liquid waste may produce hydrogen as result of the interaction of gamma radiation and water. If the waste contains organic chelating agents, additional hydrogen as well as nitrous oxide and ammonia may be produced by thermal and radiolytic decomposition of these organics. Several high-level radioactive liquid waste storage tanks, located underground at the Hanford Site in Washington State, are on a Flammable Gas Watch List. Some contain waste that produces and retains gases until large quantities of gas are released rapidly to the tank vapor space. Tanks nearly-filled to capacity have relatively little vapor space; therefore if the waste suddenly releases a large amount of hydrogen and nitrous oxide, a flammable gas mixture could result. The most notable example of a Hanford waste tank with a flammable gas problem is tank 241-SY-101. Upon occasion waste stored in this tank has released enough flammable gas to burn if an ignition source had been present inside of the tank. Several, other Hanford waste tanks exhibit similar behavior although to a lesser magnitude. Because this behavior was hot adequately-addressed in safety analysis reports for the Hanford Tank Farms, an unreviewed safety question was declared, and in 1990 the Flammable Gas Tank Safety Program was established to address this problem. The purposes of the program are a follows: (1) Provide safety documents to fill gaps in the safety analysis reports, and (2) Resolve the safety issue by acquiring knowledge about gas retention and release from radioactive liquid waste and developing mitigation technology. This document provides the general logic and work activities required to resolve the unreviewed safety question and the safety issue of flammable gas mixtures in radioactive liquid waste storage tanks

TRU waste transportation -- The flammable gas generation problem

International Nuclear Information System (INIS)

Connolly, M.J.; Kosiewicz, S.T.

1997-01-01

The Nuclear Regulatory Commission (NRC) has imposed a flammable gas (i.e., hydrogen) concentration limit of 5% by volume on transuranic (TRU) waste containers to be shipped using the TRUPACT-II transporter. This concentration is the lower explosive limit (LEL) in air. This was done to minimize the potential for loss of containment during a hypothetical 60 day period. The amount of transuranic radionuclide that is permissible for shipment in TRU waste containers has been tabulated in the TRUPACT-II Safety Analysis Report for Packaging (SARP, 1) to conservatively prevent accumulation of hydrogen above this 5% limit. Based on the SARP limitations, approximately 35% of the TRU waste stored at the Idaho National Engineering and Environmental Lab (INEEL), Los Alamos National Lab (LANL), and Rocky Flats Environmental Technology Site (RFETS) cannot be shipped in the TRUPACT-II. An even larger percentage of the TRU waste drums at the Savannah River Site (SRS) cannot be shipped because of the much higher wattage loadings of TRU waste drums in that site's inventory. This paper presents an overview of an integrated, experimental program that has been initiated to increase the shippable portion of the Department of Energy (DOE) TRU waste inventory. In addition, the authors will estimate the anticipated expansion of the shippable portion of the inventory and associated cost savings. Such projection should provide the TRU waste generating sites a basis for developing their TRU waste workoff strategies within their Ten Year Plan budget horizons

FLAMMABLE GAS DIFFUSION THROUGH SINGLE SHELL TANK (SST) DOMES

Energy Technology Data Exchange (ETDEWEB)

MEACHAM, J.E.

2003-11-10

This report quantified potential hydrogen diffusion through Hanford Site Single-Shell tank (SST) domes if the SSTs were hypothetically sealed airtight. Results showed that diffusion would keep headspace flammable gas concentrations below the lower flammability limit in the 241-AX and 241-SX SST. The purpose of this document is to quantify the amount of hydrogen that could diffuse through the domes of the SSTs if they were hypothetically sealed airtight. Diffusion is assumed to be the only mechanism available to reduce flammable gas concentrations. The scope of this report is limited to the 149 SSTs.

Strategy for resolution of the flammable gas safety issue

International Nuclear Information System (INIS)

Johnson, G.D.

1997-01-01

This document provides a strategy for resolution of the Flammable Gas Safety Issue. It defines the key elements required for the following: Closing the Flammable Gas Unreviewed Safety Question (USQ); Providing the administrative basis for resolving the safety issue; Defining the data needed to support these activities; and Providing the technical and administrative path for removing tanks from the Watch List

Strategy for resolution of the flammable gas safety issue

Energy Technology Data Exchange (ETDEWEB)

Johnson, G.D.

1997-05-23

This document provides a strategy for resolution of the Flammable Gas Safety Issue. It defines the key elements required for the following: Closing the Flammable Gas Unreviewed Safety Question (USQ); Providing the administrative basis for resolving the safety issue; Defining the data needed to support these activities; and Providing the technical and administrative path for removing tanks from the Watch List.

A risk-based approach to flammable gas detector spacing.

Science.gov (United States)

Defriend, Stephen; Dejmek, Mark; Porter, Leisa; Deshotels, Bob; Natvig, Bernt

2008-11-15

offshore facilities, it is conventional to use computational fluid dynamics (CFD) modeling to determine the size of a flammable cloud that would result from a specific leak scenario. Simpler modeling methods can be used, but the results are not very accurate in the region near the release, especially where flow obstructions are present. The results from CFD analyses on several leak scenarios can be plotted to determine the size of a flammable cloud that could result in an explosion that would generate overpressure exceeding the strength of the mechanical design of the plant. A cloud of this size has the potential to produce a blast pressure or flying debris capable of causing a fatality or subsequent damage to vessels or piping containing hazardous material. In cases where the leak results in a fire, rather than explosion, CFD or other modeling methods can estimate the size of a leak that would cause a fire resulting in subsequent damage to the facility, or would prevent the safe escape of personnel. The gas detector system must be capable of detecting a gas release or vapor cloud, and initiating action to prevent the leak from reaching a size that could cause injury or severe damage upon ignition.

Flammable gas tank safety program: Technical basis for gas analysis and monitoring

International Nuclear Information System (INIS)

Estey, S.D.

1998-01-01

Several Hanford waste tanks have been observed to exhibit periodic releases of significant quantities of flammable gases. Because potential safety issues have been identified with this type of waste behavior, applicable tanks were equipped with instrumentation offering the capability to continuously monitor gases released from them. This document was written to cover three primary areas: (1) describe the current technical basis for requiring flammable gas monitoring, (2) update the technical basis to include knowledge gained from monitoring the tanks over the last three years, (3) provide the criteria for removal of Standard Hydrogen Monitoring System(s) (SHMS) from a waste tank or termination of other flammable gas monitoring activities in the Hanford Tank farms

Remote flammable gas detection/measuring device.

CSIR Research Space (South Africa)

Kononov, VA

1999-11-01

Full Text Available This research report presents the results of an evaluation of the existing open path remote flammable gas detection/monitoring technology and provides recommendations on possible limited implementation of this technology and future development...

Summary of tank information relating salt well pumping to flammable gas safety issues

International Nuclear Information System (INIS)

Caley, S.M.; Mahoney, L.A.; Gauglitz, P.A.

1996-09-01

The Hanford Site has 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. Active use of these SSTs was phased out completely by November 1980, and the first step toward final disposal of the waste in the SSTs is interim stabilization, which involves removing essentially all of the drainable liquid from the tank. Stabilization can be achieved administratively, by jet pumping to remove drainable interstitial liquid, or by supernatant pumping. To date, 116 tanks have been declared interim stabilized; 44 SSTs have had drainable liquid removed by salt well jet pumping. Of the 149 SSTs, 19 are on the Flammable Gas Watch List (FGWL) because the waste in these tanks is known or suspected, in all but one case, to generate and retain mixtures of flammable gases, including; hydrogen, nitrous oxide, and ammonia. Salt well pumping to remove the drainable interstitial liquid from these SSTs is expected to cause the release of much of the retained gas, posing a number of safety concerns. The scope of this work is to collect and summarize information, primarily tank data and observations, that relate salt well pumping to flammable gas safety issues. While the waste within FGWL SSTs is suspected offering flammable gases, the effect of salt well pumping on the waste behavior is not well understood. This study is being conducted for the Westinghouse Hanford Company as part of the Flammable Gas Project at the Pacific Northwest National Laboratory (PNNL). Understanding the historical tank behavior during and following salt well pumping will help to resolve the associated safety issues

Results of Vapor Space Monitoring of Flammable Gas Watch List Tanks

Energy Technology Data Exchange (ETDEWEB)

MCCAIN, D.J.

2000-09-27

This report documents the measurement of headspace gas concentrations and monitoring results from the Hanford tanks that have continuous flammable gas monitoring. The systems used to monitor the tanks are Standard Hydrogen Monitoring Systems. Further characterization of the tank off-gases was done with Gas Characterization systems and vapor grab samples. The background concentrations of all tanks are below the action level of 6250 ppm. Other information which can be derived from the measurements (such as generation rate, released rate, and ventilation rate) is also discussed.

Results of vapor space monitoring of flammable gas Watch List tanks

International Nuclear Information System (INIS)

Wilkins, N.E.

1997-01-01

This report documents the measurement of headspace gas concentrations and monitoring results from the Hanford tanks that have continuous flammable gas monitoring. The systems used to monitor the tanks are Standard Hydrogen Monitoring Systems. Further characterization of the tank off-gases was done with Gas Characterization Systems and vapor grab samples. The background concentrations of all tanks are below the action level of 6250 ppm. Other information which can be derived from the measurements (such as generation rate, release rate, and ventilation rate) is also discussed

Fixed target flammable gas upgrades

International Nuclear Information System (INIS)

Schmitt, R.; Squires, B.; Gasteyer, T.; Richardson, R.

1996-12-01

In the past, fixed target flammable gas systems were not supported in an organized fashion. The Research Division, Mechanical Support Department began to support these gas systems for the 1995 run. This technical memo describes the new approach being used to supply chamber gasses to fixed target experiments at Fermilab. It describes the engineering design features, system safety, system documentation and performance results. Gas mixtures provide the medium for electron detection in proportional and drift chambers. Usually a mixture of a noble gas and a polyatomic quenching gas is used. Sometimes a small amount of electronegative gas is added as well. The mixture required is a function of the specific chamber design, including working voltage, gain requirements, high rate capability, aging and others. For the 1995 fixed target run all the experiments requested once through gas systems. We obtained a summary of problems from the 1990 fixed target run and made a summary of the operations logbook entries from the 1991 run. These summaries primarily include problems involving flammable gas alarms, but also include incidents where Operations was involved or informed. Usually contamination issues were dealt with by the experimenters. The summaries are attached. We discussed past operational issues with the experimenters involved. There were numerous incidents of drift chamber failure where contaminated gas was suspect. However analyses of the gas at the time usually did not show any particular problems. This could have been because the analysis did not look for the troublesome component, the contaminant was concentrated in the gas over the liquid and vented before the sample was taken, or that contaminants were drawn into the chambers directly through leaks or sub-atmospheric pressures. After some study we were unable to determine specific causes of past contamination problems, although in argon-ethane systems the problems were due to the ethane only

46 CFR 111.105-32 - Bulk liquefied flammable gas and ammonia carriers.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Bulk liquefied flammable gas and ammonia carriers. 111... gas and ammonia carriers. (a) Each vessel that carries bulk liquefied flammable gases or ammonia as a.... (2) The term “gas-dangerous” does not include the weather deck of an ammonia carrier. (c) Each...

The role of quantitative uncertainty in the safety analysis of flammable gas accidents in Hanford waste tanks

International Nuclear Information System (INIS)

Bratzel, D.R.

1998-01-01

Following a 1990 investigation into flammable gas generation, retention, and release mechanisms within the Hanford Site high-level waste tanks, personnel concluded that the existing Authorization Basis documentation did not adequately evaluate flammable gas hazards. The US Department of Energy Headquarters subsequently declared the flammable gas hazard as an unresolved safety issue. Although work scope has been focused on resolution of the issue, it has yet to be resolved due to considerable uncertainty regarding essential technical parameters and associated risk. Resolution of the Flammable Gas Safety Issue will include the identification of a set of controls for the Authorization Basis for the tanks which will require a safety analysis of flammable gas accidents. A traditional nuclear facility safety analysis is based primarily on the analysis of a set of bounding accidents to represent the risks of the possible accidents and hazardous conditions at a facility. While this approach may provide some indication of the bounding consequences of accidents for facilities, it does not provide a satisfactory basis for identification of facility risk or safety controls when there is considerable uncertainty associated with accident phenomena and/or data as is the case with potential flammable gas accidents at the Hanford Site. This is due to the difficulties in identifying the bounding case and reaching consensus among safety analysts, facility operations and engineering, and the regulator on the implications of the safety analysis results. In addition, the bounding cases are frequently based on simplifying assumptions that make the analysis results insensitive to variations among facilities or the impact of alternative safety control strategies. The existing safety analysis of flammable gas accidents for the Tank Waste Remediation system (TWRS) at the Hanford Site has these difficulties. However, Hanford Site personnel are developing a refined safety analysis approach

DWPF Melter Off-Gas Flammability Assessment for Sludge Batch 9

Energy Technology Data Exchange (ETDEWEB)

Choi, A. S. [Savannah River Site (SRS), Aiken, SC (United States)

2016-07-11

The slurry feed to the Defense Waste Processing Facility (DWPF) melter contains several organic carbon species that decompose in the cold cap and produce flammable gases that could accumulate in the off-gas system and create potential flammability hazard. To mitigate such a hazard, DWPF has implemented a strategy to impose the Technical Safety Requirement (TSR) limits on all key operating variables affecting off-gas flammability and operate the melter within those limits using both hardwired/software interlocks and administrative controls. The operating variables that are currently being controlled include; (1) total organic carbon (TOC), (2) air purges for combustion and dilution, (3) melter vapor space temperature, and (4) feed rate. The safety basis limits for these operating variables are determined using two computer models, 4-stage cold cap and Melter Off-Gas (MOG) dynamics models, under the baseline upset scenario - a surge in off-gas flow due to the inherent cold cap instabilities in the slurry-fed melter.

Control Decisions for Flammable Gas Hazards in Waste Transfer Systems

International Nuclear Information System (INIS)

KRIPPS, L.J.

2000-01-01

This report describes the control decisions for flammable gas hazards in waste transfer systems (i.e., waste transfer piping and waste transfer-associated structures) made at control decision meetings on November 30, 1999a and April 19, 2000, and their basis. These control decisions, and the analyses that support them, will be documented in an amendment to the Final Safety Analysis Report (FSAR) (CHG 2000a) and Technical Safety Requirements (TSR) (CHG 2000b) to close the Flammable Gas Unreviewed Safety Question (USQ) (Bacon 1996 and Wagoner 1996). Following the Contractor Tier I review of the FSAR and TSR amendment, it will be submitted to the US. Department of Energy (DOE), Office of River Protection (ORP) for review and approval. The control decision meeting on November 30, 1999 to address flammable gas hazards in waste transfer systems followed the control decision process and the criteria for control decisions described in Section 3.3.1.5 of the FSAR. The control decision meeting agenda, attendance list, and introductory and background presentations are included in Attachments 1 through 4. The control decision discussions on existing and other possible controls for flammable gas hazards in waste transfer systems and the basis for selecting or not selecting specific controls are summarized in this report

Methods of Off-Gas Flammability Control for DWPF Melter Off-Gas System at Savannah River Site

International Nuclear Information System (INIS)

Choi, A.S.; Iverson, D.C.

1996-01-01

Several key operating variables affecting off-gas flammability in a slurry-fed radioactive waste glass melter are discussed, and the methods used to prevent potential off-gas flammability are presented. Two models have played a central role in developing such methods. The first model attempts to describe the chemical events occurring during the calcining and melting steps using a multistage thermodynamic equilibrium approach, and it calculates the compositions of glass and calcine gases. Volatile feed components and calcine gases are fed to the second model which then predicts the process dynamics of the entire melter off-gas system including off-gas flammability under both steady state and various transient operating conditions. Results of recent simulation runs are also compared with available data

Evaluation of Flammable Gas Monitoring and Ventilation System Alternatives for Double-Contained Receiver Tanks

International Nuclear Information System (INIS)

GUSTAVSON, R.D.

1999-01-01

This study identifies possible flammable gas monitoring and ventilation system alternatives to ensure adequate removal of flammable gases from the Double-Contained Receiver Tank (DCRT) primary tanks during temporary storage of small amounts of waste. The study evaluates and compares these alternatives to support closure of the Flammable Gas Unreviewed Safety Question (USQ TF-96-04330)

STEADY STATE FLAMMABLE GAS RELEASE RATE CALCULATION AND LOWER FLAMMABILITY LEVEL EVALUATION FOR HANFORD TANK WASTE

Energy Technology Data Exchange (ETDEWEB)

HU TA

2009-10-26

Assess the steady-state flammability level at normal and off-normal ventilation conditions. The hydrogen generation rate was calculated for 177 tanks using the rate equation model. Flammability calculations based on hydrogen, ammonia, and methane were performed for 177 tanks for various scenarios.

Flammable gas project expert elicitation results for Hanford Site double-shell tanks

International Nuclear Information System (INIS)

Bratzel, D.R.

1998-01-01

This report documents the results of the second phase of parameter quantification by the flammable gas expert panel. This second phase is focused on the analysis of flammable gas accidents in the Hanford Site double-shell tanks. The first phase of parameter quantification, performed in 1997 was focused on the analysis of Hanford single-shell tanks

A refined safety analysis approach for closure of the Hanford Site flammable gas unreviewed safety question

International Nuclear Information System (INIS)

Bratzel, D.R.

1997-01-01

Following a 1990 investigation into flammable gas generation, retention, and release mechanisms within the Hanford Site high-level waste tanks, personnel concluded that the existing Authorization Basis documentation did not adequately evaluate flammable gas hazards. This declaration was based primarily on the fact that personnel did not adequately consider hydrogen and nitrous oxide evolution within the material in certain waste tanks and subsequent hypothetical ignition in the development of safety documentation for the waste tanks. The US Department of Energy-Headquarters subsequently declared an Unreviewed Safety Question (USQ). Although work scope has been focused on closure of the USQ since 1990, the DOE has yet to close the USQ because of considerable uncertainty regarding essential technical parameters and associated risk. The DOE recently approved a Basis for Interim Operation to revise the Authorization Basis for managing the tank farms, however, the USQ remains open. The two fundamental requirements for closure of the flammable gas USQ are as follows: development of a defensible technical basis for existing controls; development of a process to assess the adequacy of controls as the waste tank mission progresses

Engineering task plan for flammable gas atmosphere mobile color video camera systems

International Nuclear Information System (INIS)

Kohlman, E.H.

1995-01-01

This Engineering Task Plan (ETP) describes the design, fabrication, assembly, and testing of the mobile video camera systems. The color video camera systems will be used to observe and record the activities within the vapor space of a tank on a limited exposure basis. The units will be fully mobile and designed for operation in the single-shell flammable gas producing tanks. The objective of this tank is to provide two mobile camera systems for use in flammable gas producing single-shell tanks (SSTs) for the Flammable Gas Tank Safety Program. The camera systems will provide observation, video recording, and monitoring of the activities that occur in the vapor space of applied tanks. The camera systems will be designed to be totally mobile, capable of deployment up to 6.1 meters into a 4 inch (minimum) riser

Development of a cost efficient methodology to perform allocation of flammable and toxic gas detectors applying CFD tools

Energy Technology Data Exchange (ETDEWEB)

Storch, Rafael Brod; Rocha, Gean Felipe Almeida [Det Norske Veritas (DNV), Rio de Janeiro, RJ (Brazil); Nalvarte, Gladys Augusta Zevallos [Det Norske Veritas (DNV), Novik (Norway)

2012-07-01

This paper is aimed to present a computational procedure for flammable and toxic gas detector allocation and quantification developed by DNV. The proposed methodology applies Computational Fluid Dynamics (CFD) simulations as well as operational and safety characteristics of the analyzed region to assess the optimal number of toxic and flammable gas detectors and their optimal location. A probabilistic approach is also used when applying the DNV software ThorEXPRESSLite, following NORSOK Z013 Annex G and presented in HUSER et al. 2000 and HUSER et al. 2001, when the flammable gas detectors are assessed. A DNV developed program, DetLoc, is used to run in an iterative way the procedure described above leading to an automatic calculation of the gas detectors location and number. The main advantage of the methodology presented above is the independence of human interaction in the gas detector allocation leading to a more precise and free of human judgment allocation. Thus, a reproducible allocation is generated when comparing several different analyses and a global criteria appliance is guaranteed through different regions in the same project. A case study is presented applying the proposed methodology. (author)

An approximate-reasoning-based method for screening flammable gas tanks

International Nuclear Information System (INIS)

Eisenhawer, S.W.; Bott, T.F.; Smith, R.E.

1998-03-01

High-level waste (HLW) produces flammable gases as a result of radiolysis and thermal decomposition of organics. Under certain conditions, these gases can accumulate within the waste for extended periods and then be released quickly into the dome space of the storage tank. As part of the effort to reduce the safety concerns associated with flammable gas in HLW tanks at Hanford, a flammable gas watch list (FGWL) has been established. Inclusion on the FGWL is based on criteria intended to measure the risk associated with the presence of flammable gas. It is important that all high-risk tanks be identified with high confidence so that they may be controlled. Conversely, to minimize operational complexity, the number of tanks on the watchlist should be reduced as near to the true number of flammable risk tanks as the current state of knowledge will support. This report presents an alternative to existing approaches for FGWL screening based on the theory of approximate reasoning (AR) (Zadeh 1976). The AR-based model emulates the inference process used by an expert when asked to make an evaluation. The FGWL model described here was exercised by performing two evaluations. (1) A complete tank evaluation where the entire algorithm is used. This was done for two tanks, U-106 and AW-104. U-106 is a single shell tank with large sludge and saltcake layers. AW-104 is a double shell tank with over one million gallons of supernate. Both of these tanks had failed the screening performed by Hodgson et al. (2) Partial evaluations using a submodule for the predictor likelihood for all of the tanks on the FGWL that had been flagged previously by Whitney (1995)

The effect of hydrogen enrichment towards the flammability limits of natural gas in conventional combustion

International Nuclear Information System (INIS)

Izirwan Izhab; Nur Syuhada Mohd Shokri; Nurul Saadah Sulaiman; Mohd Zulkifli Mohamad Noor; Siti Zubaidah Sulaiman; Rosmawati Naim; Norida Ridzuan, Mohd Masri Razak; Abdul Halim Abdul Razik; Zulkafli Hassan

2010-01-01

The use of hydrogenated fuels shows a considerable promise for the applications in gas turbines and internal combustion engines. The aims of this study are to determine the flammability limits of natural gas/ air mixtures and to investigate the effect of hydrogen enrichment on the flammability limits of natural gas/ air mixtures up to 60 vol % of hydrogen/fuel volume ratio at atmospheric pressure and ambient temperature. The experiments were performed in a 20 L closed explosion vessel where the mixtures were ignited by using a spark permanent wire that was placed at the centre of the vessel. The pressure-time variations during explosions of natural gas/ air mixtures in an explosion vessel were recorded. Moreover, the explosion pressure data is used to determine the flammability limits that flame propagation is considered to occur if explosion pressure is greater than 0.1 bar. Therefore, in this study, the results show that the range of flammability limits are from 6 vol % to 15 vol % and by the addition of hydrogen in natural gas proved to extend the initial lower flammability limit of 6 vol % to 2 vol % of methane. (author)

Characterization strategy for the flammable gas safety issue

International Nuclear Information System (INIS)

Stewart, C.W.; Brewster, M.E.; Roberts, J.S.

1997-06-01

The characterization strategy for resolving the flammable gas safety issue for Hanford waste tanks is based on a structured logic diagram (SLD) that displays the outcomes necessary to reach the desired goal of making flammable gas risk acceptable. The diagram provides a structured path that can identify all information inputs, data as well as models, needed to achieve the goal. Tracing the path from need to outcome provides an immediate and clear justification and defense of a specific need. The diagram itself is a open-quote picture of a risk calculation close-quote and forms the basis for a quantitative model of risk. The SLID, with the risk calculation, identifies options for characterization, mitigation, and controls that have the maximum effect in reducing risk. It provides quantitative input to risk-based decision making so that options are chosen for maximum impact at least cost

Project W-030 flammable gas verification monitoring test

International Nuclear Information System (INIS)

BARKER, S.A.

1999-01-01

This document describes the verification monitoring campaign used to document the ability of the new ventilation system to mitigate flammable gas accumulation under steady state tank conditions. This document reports the results of the monitoring campaign. The ventilation system configuration, process data, and data analysis are presented

Results of gas monitoring of double-shell flammable gas watch list tanks

International Nuclear Information System (INIS)

Wilkins, N.E.

1995-01-01

Tanks 103-SY; 101-AW; 103-, 104-, and 105-AN are on the Flammable Gas Watch List. Recently, standard hydrogen monitoring system (SHMS) cabinets have been installed in the vent header of each of these tanks. Grab samples have been taken once per week, and a gas chromatograph was installed on tank 104-AN as a field test. The data that have been collected since gas monitoring began on these tanks are summarized in this document

Equipment design guidance document for flammable gas waste storage tank new equipment

International Nuclear Information System (INIS)

Smet, D.B.

1996-01-01

This document is intended to be used as guidance for design engineers who are involved in design of new equipment slated for use in Flammable Gas Waste Storage Tanks. The purpose of this document is to provide design guidance for all new equipment intended for application into those Hanford storage tanks in which flammable gas controls are required to be addressed as part of the equipment design. These design criteria are to be used as guidance. The design of each specific piece of new equipment shall be required, as a minimum to be reviewed by qualified Unreviewed Safety Question evaluators as an integral part of the final design approval. Further Safety Assessment may be also needed. This guidance is intended to be used in conjunction with the Operating Specifications Documents (OSDs) established for defining work controls in the waste storage tanks. The criteria set forth should be reviewed for applicability if the equipment will be required to operate in locations containing unacceptable concentrations of flammable gas

Flammability Assessment Methodology Program Phase I: Final Report

Energy Technology Data Exchange (ETDEWEB)

C. A. Loehr; S. M. Djordjevic; K. J. Liekhus; M. J. Connolly

1997-09-01

The Flammability Assessment Methodology Program (FAMP) was established to investigate the flammability of gas mixtures found in transuranic (TRU) waste containers. The FAMP results provide a basis for increasing the permissible concentrations of flammable volatile organic compounds (VOCs) in TRU waste containers. The FAMP results will be used to modify the ''Safety Analysis Report for the TRUPACT-II Shipping Package'' (TRUPACT-II SARP) upon acceptance of the methodology by the Nuclear Regulatory Commission. Implementation of the methodology would substantially increase the number of drums that can be shipped to the Waste Isolation Pilot Plant (WIPP) without repackaging or treatment. Central to the program was experimental testing and modeling to predict the gas mixture lower explosive limit (MLEL) of gases observed in TRU waste containers. The experimental data supported selection of an MLEL model that was used in constructing screening limits for flammable VOC and flammable gas concentrations. The MLEL values predicted by the model for individual drums will be utilized to assess flammability for drums that do not meet the screening criteria. Finally, the predicted MLEL values will be used to derive acceptable gas generation rates, decay heat limits, and aspiration time requirements for drums that do not pass the screening limits. The results of the program demonstrate that an increased number of waste containers can be shipped to WIPP within the flammability safety envelope established in the TRUPACT-II SARP.

Data Observations on Double Shell Tank (DST) Flammable Gas Watch List Tank Behavior

Energy Technology Data Exchange (ETDEWEB)

HEDENGREN, D.C.

2000-09-28

This report provides the data from the retained gas sampler, void fraction instrument, ball rheometer, standard hydrogen monitoring system, and other tank data pertinent to gas retention and release behavior in the waste stored in double-shelled Flammable Gas Watch List tanks at Hanford. These include tanks 241-AN-103,241-AN-104, 241-AN-105, 241-AW-101, 241-SY-101, and 241-SY-103. The tanks and the waste they contain are described in terms of fill history and chemistry. The results of mixer pump operation and recent waste transfers and back-dilution in SY-101 are also described. In-situ measurement and monitoring systems are described and the data are summarized under the categories of thermal behavior, waste configuration and properties, gas generation and composition, gas retention and historical gas release behavior.

A model of gas generation and transport within TRU [transuranic] waste drums

International Nuclear Information System (INIS)

Smith, F.G. III.

1987-01-01

Gas generation from the radiolytic decomposition of organic material contaminated with plutonium is modeled. Concentrations of gas throughout the waste drum are determined using a diffusional transport model. The model accurately reproduces experimentally measured gas concentrations. With polyethylene waste in unvented drums, the model predicts that hydrogen gas can accumulate to concentrations greater than 4 mole percent (lower flammable limit) with about 5 Ci of plutonium. Polyethylene provides a worst case for combustible waste material. If the drum liner is punctured and a carbon composite filter vent is installed in the drum lid, the plutonium loading can be increased to 240 Ci without generating flammable gas mixtures. 5 refs., 7 figs., 4 tabs

Progress toward mitigation of flammable gas Tank 241-SY-101

International Nuclear Information System (INIS)

Lentsch, J.W.; Babad, H.; Hanson, C.E.; Kirch, N.W.

1994-01-01

The mixing pump installed in Hanford Site tank 241-SY-101 has been shown to be effective in releasing flammable gases in a controlled manner. This controlled release of gas prevents the accumulation and episodic release above flammable limits. More work needs to be done to optimize the pumping operation, and to evaluate the long-term effects of mixing so as to assure that no undesirable changes have occurred to the waste. Other alternative mitigation concepts are still being evaluated as a backup to mixing

Flammability of Gas-Filled Polymers

Directory of Open Access Journals (Sweden)

Ushkov Valentin Anatol'evich

2017-09-01

Full Text Available The regularities of flame propagation on the horizontal surface of gas-filled polymers are considered depending on the concentration of oxygen in the oxidizer flow. The values of the coefficients in the expression describing relationship between the rate of flame propagation on the surface of foams and oxygen concentration are obtained. It was shown that with the mass content of reactive organophosphorus compounds reaching 4.0...5.9%, non-smoldering resole foam plastics with high performance characteristics are obtained. It was found that in order to obtain moderately combustible polyurethane foams based on oxyethylated phosphorus-containing polyols, the phosphorus concentration should not exceed 3 % of mass. To obtain flame-retardant urea-formaldehyde foam cellular plastics, the concentration of phosphorus should not exceed 0.3 % of mass. Physical-mechanical properties and flammability indices of developed gas-filled polymers based on reactive oligomers are presented.

Strategy for resolution of the Flammable Gas Safety Issue

International Nuclear Information System (INIS)

Johnson, G.D.

1995-01-01

The purpose of this document is to provide the general strategy for resolution of the flammable gas safety issue; it is not a detailed description of program activities. budgets and schedules. Details of the program activities have been issued (Johnson and Sherwood, 1994) and the information pertaining to budgets is provided in the FY 1995-1997 Multi-Year Work Plan for Tank Waste Remediation System (TWRS) (Program Element 1.1.1.2.02.). The key element in this strategy is to provide an understanding of the behavior of each of the Flammable Gas Watch List tanks. While a review of historical information does provide some insight, it is necessary to gather current information about the gases, behavior and nature of the waste,. and about the control systems that maintain and monitor the waste. Analysis of this information will enable TWRS to determine the best approach to place any tank in a safe condition, if it is found to be in an unsafe state

Evaluation of mitigation strategies in Facility Group 1 double-shell flammable-gas tanks at the Hanford Site

International Nuclear Information System (INIS)

Unal, C.; Sadasivan, P.; Kubic, W.L.; White, J.R.

1997-11-01

Radioactive nuclear waste at the Hanford Site is stored in underground waste storage tanks at the site. The tanks fall into two main categories: single-shell tanks (SSTs) and double-shell tanks (DSTs). There are a total of 149 SSTs and 28 DSTs. The wastes stored in the tanks are chemically complex. They basically involve various sodium salts (mainly nitrite, nitrate, carbonates, aluminates, and hydroxides), organic compounds, heavy metals, and various radionuclides, including cesium, strontium, plutonium, and uranium. The waste is known to generate flammable gas (FG) [hydrogen, ammonia, nitrous oxide, hydrocarbons] by complex chemical reactions. The process of gas generation, retention, and release is transient. Some tanks reach a quasi-steady stage where gas generation is balanced by the release rate. Other tanks show continuous cycles of retention followed by episodic release. There currently are 25 tanks on the Flammable Gas Watch List (FGWL). The objective of this report is to evaluate possible mitigation strategies to eliminate the FG hazard. The evaluation is an engineering study of mitigation concepts for FG generation, retention, and release behavior in Tanks SY-101, AN-103, AN 104, An-105, and Aw-101. Where possible, limited quantification of the effects of mitigation strategies on the FG hazard also is considered. The results obtained from quantification efforts discussed in this report should be considered as best-estimate values. Results and conclusions of this work are intended to help in establishing methodologies in the contractor's controls selection analysis to develop necessary safety controls for closing the FG unreviewed safety question. The general performance requirements of any mitigation scheme are discussed first

Control Decisions for Flammable Gas Hazards in Double Contained Receiver Tanks (DCRTs)

Energy Technology Data Exchange (ETDEWEB)

KRIPPS, L.J.

2000-06-28

This report describes the control decisions for flammable gas hazards in double-contained receiver tanks (DCRTs) made at control decision meetings on November 16, 17, and 18, 1999, on April 19,2000, and on May 10,2000, and their basis. These control decisions, and the analyses that support them, will be documented in an amendment to the Final Safety Analysis Report (FSAR) (CHG 2000a) and Technical Safety Requirements (TSR) (CHG 2000b) to close the Flammable Gas Unreviewed Safety Question (USQ) (Bacon 1996 and Wagoner 1996) for DCRTs. Following the contractor Tier I review of the FSAR and TSR amendment, it will be submitted to the U.S. Department of Energy (DOE), Office of River Protection (ORP) for review and approval.

Thermal and Radiolytic Gas Generation Tests on Material from Tanks 241-U-103, 241-AW-101, 241-S-106, and 241-S-102: Status Report

International Nuclear Information System (INIS)

King, C.M.; Bryan, S.A.

1999-01-01

This report summarizes progress in evaluating thermal and radiolytic flammable gas generation in actual Hanford single-shell tank wastes. The work described was conducted at Pacific Northwest National Laboratory (PNNL) for the Flammable Gas Safety Project, whose purpose is to develop information to support DE and S Hanford (DESH) and Project Management Hanford Contract (PHMC) subcontractors in their efforts to ensure the safe interim storage of wastes at the Hanford Site. This work is related to gas generation studies performed by Numatec Hanford Corporation (formerly Westinghouse Hanford Company). This report describes the results of laboratory tests of gas generation from actual convective layer wastes from Tank 241-U-103 under thermal and radiolytic conditions. Accurate measurements of gas generation rates from highly radioactive tank wastes are needed to assess the potential for producing and storing flammable gases within the tanks. The gas generation capacity of the waste in Tank 241-U-103 is a high priority for the Flammable Gas Safety Program due to its potential for accumulating gases above the flammability limit (Johnson et al, 1997). The objective of this work was to establish the composition of gaseous degradation products formed in actual tank wastes by thermal and radiolytic processes as a function of temperature. The gas generation tests on Tank 241-U-103 samples focused first on the effect of temperature on the composition and rate of gas generation Generation rates of nitrogen, nitrous oxide, methane, and hydrogen increased with temperature, and the composition of the product gas mixture varied with temperature

Modelling of hot surface ignition within gas turbines subject to flammable gas in the intake

DEFF Research Database (Denmark)

Pedersen, Lea Duedahl; Nielsen, Kenny Krogh; Yin, Chungen

2017-01-01

Controlling risks associated with fires and explosions from leaks of flammable fluids at oil and gas facilities is paramount to ensuring safe operations. The gas turbine is a significant potential source of ignition; however, the residual risk is still not adequately understood. A model has been...... but decreases with increase in initial mixture temperature and pressure. The model shows a great potential in reliable prediction of the risk of hot surface ignition within gas turbines in the oil and gas industry. In the future, a dedicated experimental study will be performed not only to improve...

Safety basis for selected activities in single-shell tanks with flammable gas concerns. Revision 1

International Nuclear Information System (INIS)

Schlosser, R.L.

1996-01-01

This is full revision to Revision 0 of this report. The purpose of this report is to provide a summary of analyses done to support activities performed for single-shell tanks. These activities are encompassed by the flammable gas Unreviewed Safety Question (USQ). The basic controls required to perform these activities involve the identification, elimination and/or control of ignition sources and monitoring for flammable gases. Controls are implemented through the Interim Safety Basis (ISB), IOSRs, and OSDs. Since this report only provides a historical compendium of issues and activities, it is not to be used as a basis to perform USQ screenings and evaluations. Furthermore, these analyses and others in process will be used as the basis for developing the Flammable Gas Topical Report for the ISB Upgrade

Potential Flammable Gas Explosion in the TRU Vent and Purge Machine

International Nuclear Information System (INIS)

Vincent, A

2006-01-01

The objective of the analysis was to determine the failure of the Vent and Purge (V and P) Machine due to potential explosion in the Transuranic (TRU) drum during its venting and/or subsequent explosion in the V and P machine from the flammable gases (e.g., hydrogen and Volatile Organic Compounds [VOCs]) vented into the V and P machine from the TRU drum. The analysis considers: (a) increase in the pressure in the V and P cabinet from the original deflagration in the TRU drum including lid ejection, (b) pressure wave impact from TRU drum failure, and (c) secondary burns or deflagrations resulting from excess, unburned gases in the cabinet area. A variety of cases were considered that maximized the pressure produced in the V and P cabinet. Also, cases were analyzed that maximized the shock wave pressure in the cabinet from TRU drum failure. The calculations were performed for various initial drum pressures (e.g., 1.5 and 6 psig) for 55 gallon TRU drum. The calculated peak cabinet pressures ranged from 16 psig to 50 psig for various flammable gas compositions. The blast on top of cabinet and in outlet duct ranged from 50 psig to 63 psig and 12 psig to 16 psig, respectively, for various flammable gas compositions. The failure pressures of the cabinet and the ducts calculated by structural analysis were higher than the pressure calculated from potential flammable gas deflagrations, thus, assuring that V and P cabinet would not fail during this event. National Fire Protection Association (NFPA) 68 calculations showed that for a failure pressure of 20 psig, the available vent area in the V and P cabinet is 1.7 to 2.6 times the required vent area depending on whether hydrogen or VOCs burn in the V and P cabinet. This analysis methodology could be used to design the process equipment needed for venting TRU waste containers at other sites across the Department of Energy (DOE) Complex

Flammable gas safety program. Analytical methods development: FY 1994 progress report

International Nuclear Information System (INIS)

Campbell, J.A.; Clauss, S.; Grant, K.; Hoopes, V.; Lerner, B.; Lucke, R.; Mong, G.; Rau, J.; Wahl, K.; Steele, R.

1994-09-01

This report describes the status of developing analytical methods to account for the organic components in Hanford waste tanks, with particular focus on tanks assigned to the Flammable Gas Watch List. The methods that have been developed are illustrated by their application to samples obtained from Tank 241-SY-101 (Tank 101-SY)

Design review report for rotary mode core sample truck (RMCST) modifications for flammable gas tanks, preliminary design

International Nuclear Information System (INIS)

Corbett, J.E.

1996-02-01

This report documents the completion of a preliminary design review for the Rotary Mode Core Sample Truck (RMCST) modifications for flammable gas tanks. The RMCST modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to validate basic design assumptions and concepts to support a path forward leading to a final design. The conclusion reached by the review committee was that the design was acceptable and efforts should continue toward a final design review

Flammable gas safety program

International Nuclear Information System (INIS)

Campbell, J.A.; Clauss, S.; Grant, K.; Hoopes, V.; Lerner, B.; Lucke, R.; Mong, G.; Rau, J.; Steele, R.

1994-01-01

This report describes the status of developing analytical methods to account for the organic constituents in Hanford waste tanks, with particular emphasis on those tanks that have been assigned to the Flammable Gas Watch List. Six samples of core segments from Tank 101-SY, obtained during the window E core sampling, have been analyzed for organic constituents. Four of the samples were from the upper region, or convective layer, of the tank and two were from the lower, nonconvective layer. The samples were analyzed for chelators, chelator fragments, and several carboxylic acids by derivatization gas chromatography/mass spectrometry (GC/MS). The major components detected were ethylenediaminetetraacetic acid (EDTA), nitroso-iminodiacetic acid (NIDA), nitrilotriacetic acid (NTA), citric acid (CA), succinic acid (SA), and ethylenediaminetriacetic acid (ED3A). The chelator of highest concentration was EDTA in all six samples analyzed. Liquid chromatography (LC) was used to quantitate low molecular weight acids (LMWA) including oxalic, formic, glycolic, and acetic acids, which are present in the waste as acid salts. From 23 to 61% of the total organic carbon (TOC) in the samples analyzed was accounted for by these acids. Oxalate constituted approximately 40% of the TOC in the nonconvective layer samples. Oxalate was found to be approximately 3 to 4 times higher in concentration in the nonconvective layer than in the convective layer. During FY 1993, LC methods for analyzing LWMA, and two chelators N-(2-hydroxyethyl) ethylenediaminetriacetic acid and EDTA, were transferred to personnel in the Analytical Chemistry Laboratory and the 222-S laboratory

Flammable gas tank waste level reconcilliation tank 241-SX-102

International Nuclear Information System (INIS)

Brevick, C.H.; Gaddie, L.A.

1997-01-01

Fluoro Dynel Northwest (FDNW) was authorized to address flammable gas issues by reconciling the unexplained surface level increases in Tank 24 1-S-1 1 1 (S-I 1 1, typical). The trapped gas evaluation document (ref 1) states that Tank SX-102 exceeds the 25% of the lower flammable limit (FL) criterion (ref 2), based on a surface level rise evaluation. The Waste Storage Tank Status and Leak Detection Criteria document, commonly referred to as the ''Wallet Report'' is the basis for this letter report (ref 3). The Wallet Report is also a part of the trapped gas evaluation document criteria. The Wallet Report contains various tank information, including: physical information, status, levels, and dry wells, see Appendix A. The unexplained waste level rises were attributed to the production and retention of gas in the column of waste corresponding to the unacquainted for surface level rise. From 1973 through 1980, the Wallet Report tracked Tank S- 102 transfers and reported a net cumulative change of 19.95 in. This surface level increase is from an unknown source or is unacquainted for. Duke Engineering and Services Hanford (DASH) and Leached Martin Hanford Corporation (LMHC) are interested in determining the validity of the unexplained surface level changes reported in the 0611e Wallet Report based upon other corroborative sources of data. The purpose of this letter report is to assemble detailed surface level and waste addition data from daily tank records, logbooks, and other corroborative data that indicate surface levels, and to reconcile the cumulative unacquainted for surface level changes as shown in the Wallet Report from 1973 through 1980

Flammability Indices for Refrigerants

Science.gov (United States)

Kataoka, Osami

This paper introduces a new index to classify flammable refrigerants. A question on flammability indices that ASHRAE employs arose from combustion test results of R152a and ammonia. Conventional methods of not only ASHRAE but also ISO and Japanese High-pressure gas safety law to classify the flammability of refrigerants are evaluated to show why these methods conflict with the test results. The key finding of this paper is that the ratio of stoichiometric concentration to LFL concentration (R factor) represents the test results most precisely. In addition, it has excellent correlation with other flammability parameters such as flame speed and pressure rise coefficient. Classification according to this index gives reasonable flammability order of substances including ammonia, R152a and carbon monoxide. Theoretical background why this index gives good correlation is also discussed as well as the insufficient part of this method.

Operability test report for core sample truck number one flammable gas modifications

International Nuclear Information System (INIS)

Akers, J.C.

1997-01-01

This report primarily consists of the original test procedure used for the Operability Testing of the flammable gas modifications to Core Sample Truck No. One. Included are exceptions, resolutions, comments, and test results. This report consists of the original, completed, test procedure used for the Operability Testing of the flammable gas modifications to the Push Mode Core Sample Truck No. 1. Prior to the Acceptance/Operability test the truck No. 1 operations procedure (TO-080-503) was revised to be more consistent with the other core sample truck procedures and to include operational steps/instructions for the SR weather cover pressurization system. A draft copy of the operations procedure was used to perform the Operability Test Procedure (OTP). A Document Acceptance Review Form is included with this report (last page) indicating the draft status of the operations procedure during the OTP. During the OTP 11 test exceptions were encountered. Of these exceptions four were determined to affect Acceptance Criteria as listed in the OTP, Section 4.7 ACCEPTANCE CRITERIA

Flammable gas tank waste level reconciliation tank 241-SX-105

International Nuclear Information System (INIS)

Brevick, C.H.; Gaddie, L.A.

1997-01-01

Fluor Daniel Northwest was authorized to address flammable gas issues by reconciling the unexplained surface level increases in Tank 241-SX-105 (SX-105, typical). The trapped gas evaluation document states that Tank SX-105 exceeds the 25% of the lower flammable limit criterion, based on a surface level rise evaluation. The Waste Storage Tank Status and Leak Detection Criteria document, commonly referred to as the Welty Report is the basis for this letter report. The Welty Report is also a part of the trapped gas evaluation document criteria. The Welty Report contains various tank information, including: physical information, status, levels, and dry wells. The unexplained waste level rises were attributed to the production and retention of gas in the column of waste corresponding to the unaccounted for surface level rise. From 1973 through 1980, the Welty Report tracked Tank SX-105 transfers and reported a net cumulative change of 20.75 in. This surface level increase is from an unknown source or is unaccounted for. Duke Engineering and Services Hanford and Lockheed Martin Hanford Corporation are interested in determining the validity of unexplained surface level changes reported in the Welty Report based upon other corroborative sources of data. The purpose of this letter report is to assemble detailed surface level and waste addition data from daily tank records, logbooks, and other corroborative data that indicate surface levels, and to reconcile the cumulative unaccounted for surface level changes as shown in the Welty Report from 1973 through 1980. Tank SX-105 initially received waste from REDOX starting the second quarter of 1955. After June 1975, the tank primarily received processed waste (slurry) from the 242-S Evaporator/Crystallizer and transferred supernate waste to Tanks S-102 and SX-102. The Welty Report shows a cumulative change of 20.75 in. from June 1973 through December 1980

System acceptance and operability test report for the RMCS exhauster C on flammable gas tanks

International Nuclear Information System (INIS)

Waldo, E.J.

1998-01-01

This test report documents the completion of acceptance and operability testing of the rotary mode core sampling (RMCS) exhauster C, as modified for use as a major stack (as defined by the Washington State Department of Health) on flammable gas tanks

Operation of the multigap resistive plate chamber using a gas mixture free of flammable components

CERN Document Server

Akindinov, A; Antonioli, P; Arcelli, S; Basile, M; Cara Romeo, G; Cifarelli, Luisa; Cindolo, F; De Caro, A; De Pasquale, S; Di Bartolomeo, A; Fusco-Girard, M; Golovine, V; Guida, M; Hatzifotiadou, D; Kaidalov, A B; Kim, D H; Kim, D W; Kisselev, S M; Laurenti, G; Lee, K; Lee, S C; Lioublev, E; Luvisetto, M L; Margotti, A; Martemyanov, A N; Nania, R; Noferini, F; Otiougova, P; Pesci, A; Pinazza, O; Polozov, P A; Scapparone, E; Scioli, G; Sellitto, S B; Semeria, F; Smirnitsky, A V; Tchoumakov, M M; Usenko, E; Valenti, G; Voloshin, K G; Williams, M C S; Zagreev, B V; Zampolli, C; Zichichi, A

2004-01-01

We have investigated the operation of the multigap resistive plate chamber (MRPC) for the ALICE-TOF system with a gas mixture free of flammable components. Two different gas mixtures, with and without iso-C//4H//1//0 have been used to measure the performance of the MRPC. The efficiency, time resolution, total charge, and the fast to total charge ratio have been found to be comparable.

Evaluation of the generation and release of flammable gases in tank 241-SY-101

Energy Technology Data Exchange (ETDEWEB)

Babad, H.; Johnson, G.D.; Lechelt, J.A.; Reynolds, D.A. (Westinghouse Hanford Co., Richland, WA (United States)); Pederson, L.R.; Strachan, D.M. (Pacific Northwest Lab., Richland, WA (United States)); Meisel, D.; Jonah, C. (Argonne National Lab., IL (United States)); Ashby, E.C. (Georgia Inst. of Tech., Atlanta, GA (United States))

1991-11-01

Tank 241-SY-101 is a double shell, high-level waste tank located in the 200 West Area of the Hanford Site. This tank contains about 1 million gallons of waste that was concentrated at the 242-S Evaporator. Shortly after the waste was put in the tank, the waste began to expand because the generation of gases. In 1990 this tank was declared to have an unreviewed safety question because of the periodic release of hydrogen and nitrous oxide. A safety program was established to conduct a characterization of the waste and vented gases and to determine an effective means to prevent the accumulation of flammable gases in the tank dome space and ventilation system. Results of the expanded characterization conducted in fiscal year 1991 are presented. The use of gas chromatographs, mass spectrometers, and hydrogen-specific monitors provided a greater understanding of the vented gases. Additional instrumentation placed in the tank also helped to provide more detailed information on tank temperatures, gas pressure, and gas flow rates. An extensive laboratory study involving the Westinghouse Hanford Company, Pacific Northwest Laboratory, Argonne National Laboratory, and the Georgia Institute of Technology was initiated for the purpose of determining the mechanisms responsible for the generation of various gases. These studies evaluate both radiolytic and thermochemical processes. Results of the first series of experiments are described.

Flammable Gas Refined Safety Analysis Tool Software Verification and Validation Report for Resolve Version 2.5

International Nuclear Information System (INIS)

BRATZEL, D.R.

2000-01-01

The purpose of this report is to document all software verification and validation activities, results, and findings related to the development of Resolve Version 2.5 for the analysis of flammable gas accidents in Hanford Site waste tanks

Flammable gas double shell tank expert elicitation presentations (Part A and Part B)

Energy Technology Data Exchange (ETDEWEB)

Bratzel, D.R.

1998-04-17

This document is a compilation of presentation packages and white papers for the Flammable Gas Double Shell Tank Expert Elicitation Workshop {number_sign}2. For each presentation given by the different authors, a separate section was developed. The purpose for issuing these workshop presentation packages and white papers as a supporting document is to provide traceability and a Quality Assurance record for future reference to these packages.

Flammable gas double shell tank expert elicitation presentations (Part A and Part B)

International Nuclear Information System (INIS)

Bratzel, D.R.

1998-01-01

This document is a compilation of presentation packages and white papers for the Flammable Gas Double Shell Tank Expert Elicitation Workshop number-sign 2. For each presentation given by the different authors, a separate section was developed. The purpose for issuing these workshop presentation packages and white papers as a supporting document is to provide traceability and a Quality Assurance record for future reference to these packages

Electrical safety in flammable gas/vapor laden atmospheres

CERN Document Server

Korver, WOE

1992-01-01

This book provides comprehensive coverage of electrical system installation within areas where flammable gases and liquids are handled and processed. The accurate hazard evaluation of flammability risks associated with chemical and petrochemical locations is critical in determining the point at which the costs of electrical equipment and installation are balanced with explosion safety requirements. The book offers the most current code requirements along with tables and illustrations as analytic tools. Environmental characteristics are covered in Section 1 along with recommended electrical ins

Contribution to internal pressure and flammable gas concentration in RAM [radioactive material] transport packages

International Nuclear Information System (INIS)

Warrant, M.M.; Brown, N.

1989-01-01

Various facilities in the US generate wastes contaminated with transuranic (TRU) isotopes (such as plutonium and americium) that decay primarily by emission of alpha particles. The waste materials consist of a wide variety of commercially available plastics, paper, cloth, and rubber; concreted or sludge wastes containing water; and metals, glass, and other solid inorganic materials. TRU wastes that have surface dose rates of 200 mrem/hr or less are typically packaged in plastic bags placed inside metal drums or boxes that are vented through high efficiency particulate air (HEPA) filters. These wastes are to be transported from waste generation or storage sites to the Waste Isolation Pilot Plant (WIPP) in the TRUPACT-II, a Type B package. Radiolysis of organic wastes or packaging materials, or wastes containing water generates gas which may be flammable or simply contribute to the internal pressure of the radioactive material (RAM) transport package. This paper discusses the factors that affect the amount and composition of this gas, and summarizes maximum radiolytic G values (number of molecules produced per 100 eV absorbed energy) found in the technical literature for many common materials. These G values can be used to determine the combination of payload materials and decay heats that are safe for transport. G values are established for categories of materials, based on chemical functional groups. It is also shown using transient diffusion and quasi-equilibrium statistical mechanics methods that hydrogen, if generated, will not stratify at the top of the transport package void space. 9 refs., 1 tab

Gas generation from Hanford grout samples

International Nuclear Information System (INIS)

Jonah, C.D.; Kapoor, S.; Matheson, M.S.; Mulac, W.A.; Meisel, D.

1996-01-01

In an extension of our work on the radiolytic processes that occur in the waste tanks at the Hanford site, we studied the gas generation from grout samples that contained nuclear waste simulants. Grout is one option for the long-term storage of low-level nuclear waste solutions but the radiolytic effects on grout have not been thoroughly defined. In particular, the generation of potentially flammable and hazardous gases required quantification. A research team at Argonne examined this issue and found that the total amount of gases generated radiolytically from the WHC samples was an order of magnitude higher than predicted. This implies that novel pathways fro charge migration from the solid grout to the associated water are responsible for gas evolution. The grout samples produced hydrogen, nitrous oxide, and carbon monoxide as well as nitrogen and oxygen. Yields of each of these substances were determined for doses that are equivalent to about 80 years storage of the grout. Carbon monoxide, which was produced in 2% yield, is of particular importance because even small amounts may adversely affect catalytic conversion instrumentation that has been planned for installation in the storage vaults

Thermal and combined thermal and radiolytic reactions involving nitrous oxide, hydrogen, and nitrogen in the gas phase; comparison of gas generation rates in supernate and solid fractions of Tank 241-SY-101 simulated waste

International Nuclear Information System (INIS)

Bryan, S.A.; Pederson, L.R.

1995-03-01

This report summarizes progress made in evaluating me by which flammable gases are generated in Hanford double-shell tank wastes, based on the results of laboratory tests using simulated waste mixtures. Work described in this report. was conducted at Pacific Northwest Laboratory (PNL) for the Flammable Gas Safety Project, the purpose of which is to develop information needed to support Westinghouse Hanford Company (WHC) in their efforts to ensure the safe interim storage of wastes at the Hanford Site. This work is related to gas generation studies being performed at Georgia Institute of Technology (GIT), under subcontract to PNL, using simulated wastes, and to studies being performed at VMC using actual wastes

An approximate-reasoning-based method for screening high-level waste tanks for flammable gas

International Nuclear Information System (INIS)

Eisenhawer, S.W.; Bott, T.F.; Smith, R.E.

1998-01-01

The in situ retention of flammable gas produced by radiolysis and thermal decomposition in high-level waste can pose a safety problem if the gases are released episodically into the dome space of a storage tank. Screening efforts at Hanford have been directed at identifying tanks in which this situation could exist. Problems encountered in screening motivated an effort to develop an improved screening methodology. Approximate reasoning (AR) is a formalism designed to emulate the kinds of complex judgments made by subject matter experts. It uses inductive logic structures to build a sequence of forward-chaining inferences about a subject. AR models incorporate natural language expressions known as linguistic variables to represent evidence. The use of fuzzy sets to represent these variables mathematically makes it practical to evaluate quantitative and qualitative information consistently. The authors performed a pilot study to investigate the utility of AR for flammable gas screening. They found that the effort to implement such a model was acceptable and that computational requirements were reasonable. The preliminary results showed that important judgments about the validity of observational data and the predictive power of models could be made. These results give new insights into the problems observed in previous screening efforts

An Approximate Reasoning-Based Method for Screening High-Level-Waste Tanks for Flammable Gas

International Nuclear Information System (INIS)

Eisenhawer, Stephen W.; Bott, Terry F.; Smith, Ronald E.

2000-01-01

The in situ retention of flammable gas produced by radiolysis and thermal decomposition in high-level waste can pose a safety problem if the gases are released episodically into the dome space of a storage tank. Screening efforts at the Hanford site have been directed at identifying tanks in which this situation could exist. Problems encountered in screening motivated an effort to develop an improved screening methodology. Approximate reasoning (AR) is a formalism designed to emulate the kinds of complex judgments made by subject matter experts. It uses inductive logic structures to build a sequence of forward-chaining inferences about a subject. Approximate-reasoning models incorporate natural language expressions known as linguistic variables to represent evidence. The use of fuzzy sets to represent these variables mathematically makes it practical to evaluate quantitative and qualitative information consistently. In a pilot study to investigate the utility of AR for flammable gas screening, the effort to implement such a model was found to be acceptable, and computational requirements were found to be reasonable. The preliminary results showed that important judgments about the validity of observational data and the predictive power of models could be made. These results give new insights into the problems observed in previous screening efforts

An approximate reasoning-based method for screening high-level-waste tanks for flammable gas

International Nuclear Information System (INIS)

Eisenhawer, S.W.; Bott, T.F.; Smith, R.E.

2000-01-01

The in situ retention of flammable gas produced by radiolysis and thermal decomposition in high-level waste can pose a safety problem if the gases are released episodically into the dome space of a storage tank. Screening efforts at the Hanford site have been directed at identifying tanks in which this situation could exist. Problems encountered in screening motivated an effort to develop and improved screening methodology. Approximate reasoning (AR) is a formalism designed to emulate the kinds of complex judgments made by subject matter experts. It uses inductive logic structures to build a sequence of forward-chaining inferences about a subject. Approximate-reasoning models incorporate natural language expressions known as linguistic variables to represent evidence. The use of fuzzy sets to represent these variables mathematically makes it practical to evaluate quantitative and qualitative information consistently. In a pilot study to investigate the utility of AR for flammable gas screening, the effort to implement such a model was found to be acceptable, and computational requirements were found to be reasonable. The preliminary results showed that important judgments about the validity of observational data and the predictive power of models could be made. These results give new insights into the problems observed in previous screening efforts

An approximate reasoning-based method for screening high-level-waste tanks for flammable gas

Energy Technology Data Exchange (ETDEWEB)

Eisenhawer, S.W.; Bott, T.F.; Smith, R.E.

2000-06-01

The in situ retention of flammable gas produced by radiolysis and thermal decomposition in high-level waste can pose a safety problem if the gases are released episodically into the dome space of a storage tank. Screening efforts at the Hanford site have been directed at identifying tanks in which this situation could exist. Problems encountered in screening motivated an effort to develop and improved screening methodology. Approximate reasoning (AR) is a formalism designed to emulate the kinds of complex judgments made by subject matter experts. It uses inductive logic structures to build a sequence of forward-chaining inferences about a subject. Approximate-reasoning models incorporate natural language expressions known as linguistic variables to represent evidence. The use of fuzzy sets to represent these variables mathematically makes it practical to evaluate quantitative and qualitative information consistently. In a pilot study to investigate the utility of AR for flammable gas screening, the effort to implement such a model was found to be acceptable, and computational requirements were found to be reasonable. The preliminary results showed that important judgments about the validity of observational data and the predictive power of models could be made. These results give new insights into the problems observed in previous screening efforts.

Interstage Flammability Analysis Approach

Science.gov (United States)

Little, Jeffrey K.; Eppard, William M.

2011-01-01

The Interstage of the Ares I launch platform houses several key components which are on standby during First Stage operation: the Reaction Control System (ReCS), the Upper Stage (US) Thrust Vector Control (TVC) and the J-2X with the Main Propulsion System (MPS) propellant feed system. Therefore potentially dangerous leaks of propellants could develop. The Interstage leaks analysis addresses the concerns of localized mixing of hydrogen and oxygen gases to produce deflagration zones in the Interstage of the Ares I launch vehicle during First Stage operation. This report details the approach taken to accomplish the analysis. Specified leakage profiles and actual flammability results are not presented due to proprietary and security restrictions. The interior volume formed by the Interstage walls, bounding interfaces with the Upper and First Stages, and surrounding the J2-X engine was modeled using Loci-CHEM to assess the potential for flammable gas mixtures to develop during First Stage operations. The transient analysis included a derived flammability indicator based on mixture ratios to maintain achievable simulation times. Validation of results was based on a comparison to Interstage pressure profiles outlined in prior NASA studies. The approach proved useful in the bounding of flammability risk in supporting program hazard reviews.

Program plan for evaluation and remediation of the generation and release of flammable gases in Hanford Site waste tanks

International Nuclear Information System (INIS)

Johnson, G.D.

1991-08-01

This program plan describes the activities being conducted for the resolution of the flammable gas problem that is associated with 23 high-level waste tanks at the Hanford Site. The classification of the wastes in all of these tanks is not final and some wastes may not be high-level wastes. However, until the characterization and classification is complete, all the tanks are treated as if they contain high-level waste. Of the 23 tanks, Tank 241-SY-101 (referred to as Tank 101-SY) has exhibited significant episodic releases of flammable gases (hydrogen and nitrous oxide) for the past 10 years. The major near-term focus of this program is for the understanding and stabilization of this tank. An understanding of the mechanism for gas generation and the processes for the episodic release will be obtained through sampling of the tank contents, laboratory studies, and modeling of the tank behavior. Additional information will be obtained through new and upgraded instrumentation for the tank. A number of remediation, or stabilization, concepts will be evaluated for near-term (2 to 3 years) applications to Tank 101-SY. Detailed safety assessments are required for all activities that will occur in the tank (sampling, removal of equipment, and addition of new instruments). This program plan presents a discussion of each task, provides schedules for near-term activities, and gives a summary of the expected work for fiscal years 1991, 1992, and 1993. 16 refs., 7 figs., 8 tabs

Program plan for evaluation and remediation of the generation and release of flammable gases in Hanford Site waste tanks

Energy Technology Data Exchange (ETDEWEB)

Johnson, G.D. (comp.)

1991-08-01

This program plan describes the activities being conducted for the resolution of the flammable gas problem that is associated with 23 high-level waste tanks at the Hanford Site. The classification of the wastes in all of these tanks is not final and some wastes may not be high-level wastes. However, until the characterization and classification is complete, all the tanks are treated as if they contain high-level waste. Of the 23 tanks, Tank 241-SY-101 (referred to as Tank 101-SY) has exhibited significant episodic releases of flammable gases (hydrogen and nitrous oxide) for the past 10 years. The major near-term focus of this program is for the understanding and stabilization of this tank. An understanding of the mechanism for gas generation and the processes for the episodic release will be obtained through sampling of the tank contents, laboratory studies, and modeling of the tank behavior. Additional information will be obtained through new and upgraded instrumentation for the tank. A number of remediation, or stabilization, concepts will be evaluated for near-term (2 to 3 years) applications to Tank 101-SY. Detailed safety assessments are required for all activities that will occur in the tank (sampling, removal of equipment, and addition of new instruments). This program plan presents a discussion of each task, provides schedules for near-term activities, and gives a summary of the expected work for fiscal years 1991, 1992, and 1993. 16 refs., 7 figs., 8 tabs.

Investigation of flammable gas and thermal safety issues for retrieval of waste from Tank 241-AN-105

Energy Technology Data Exchange (ETDEWEB)

Caley, S.M.; Stewart, C.W.; Antoniak, Z.I.; Cuta, J.M.; Mahoney, L.A.; Panisko, F.E.

1998-09-01

The primary purpose of this report is to identify and resolve some of the flammable gas and thermal safety issues potentially associated with the retrieval of waste from Tank 241-AN-105 (AN-105), which is the first double-shell tank scheduled for waste retrieval at Hanford. The planned retrieval scenario includes the following steps in AN-105: (1) degas the tank using two submerged mixing pumps, (2) turn off the mixer pump(s) and allow any suspended solids to settle, (3) decant the supernatant to the intermediate feed staging tank(s) (IFSTs) (AP-102 and/or AP-104) using water/caustic dilution at the transfer pump inlet, (4) add the remaining dilution water/caustic to the slurry remaining in AN-105, (5) mix the tank with the mixer pump(s) until the soluble solids dissolve, (6) turn off the mixer pump(s) and let the insoluble solids settle, and (7) decant the new supernatant to the IFST(s), leaving the insoluble solids behind. Three waste retrieval safety issues are addressed in this report. They are (1) the controlled degassing of AN-105 to ensure that the headspace remains <25% of the lower flammability limit (LFL), (2) an assessment of how dissolved gas (mainly ammonia) released during the transfer of the supernatant in AN-105 to the IFSTs and the water/caustic dilution of the remaining slurry in AN-105 will affect the flammability in these tanks; and (3) an assessment of the maximum waste temperatures that might occur in AN-105 during retrieval operations.

Investigation of flammable gas and thermal safety issues for retrieval of waste from Tank 241-AN-105

International Nuclear Information System (INIS)

Caley, S.M.; Stewart, C.W.; Antoniak, Z.I.; Cuta, J.M.; Mahoney, L.A.; Panisko, F.E.

1998-09-01

The primary purpose of this report is to identify and resolve some of the flammable gas and thermal safety issues potentially associated with the retrieval of waste from Tank 241-AN-105 (AN-105), which is the first double-shell tank scheduled for waste retrieval at Hanford. The planned retrieval scenario includes the following steps in AN-105: (1) degas the tank using two submerged mixing pumps, (2) turn off the mixer pump(s) and allow any suspended solids to settle, (3) decant the supernatant to the intermediate feed staging tank(s) (IFSTs) (AP-102 and/or AP-104) using water/caustic dilution at the transfer pump inlet, (4) add the remaining dilution water/caustic to the slurry remaining in AN-105, (5) mix the tank with the mixer pump(s) until the soluble solids dissolve, (6) turn off the mixer pump(s) and let the insoluble solids settle, and (7) decant the new supernatant to the IFST(s), leaving the insoluble solids behind. Three waste retrieval safety issues are addressed in this report. They are (1) the controlled degassing of AN-105 to ensure that the headspace remains <25% of the lower flammability limit (LFL), (2) an assessment of how dissolved gas (mainly ammonia) released during the transfer of the supernatant in AN-105 to the IFSTs and the water/caustic dilution of the remaining slurry in AN-105 will affect the flammability in these tanks; and (3) an assessment of the maximum waste temperatures that might occur in AN-105 during retrieval operations

Biogas utilization as flammable for internal combustion engine

International Nuclear Information System (INIS)

Cardenas, H.

1995-01-01

In this work the energetic potential stored in form of generated biogas of organic industrial wastes treatment is analyzed. Biogas utilization as flammable at internal combustion engine coupled to electrical energy generating is studied in the Wastewater Treatment Plant of Bucaramanga city (Colombia). This Plant was designed for 160.000 habitants treatment capacity, 1300 m3/h wealth, 170 BDO/m3 residues concentration and 87% process efficiency. The plant generate 2.000 m3/d of biogas. In laboratory trials was worked with biogas originating from Treatment Plant, both without purifying and purified, and the obtained results were compared with both yields determined with 86-octanes gasoline and natural gas. The analysis of pollutant by-products generated in combustion process as leak gases, present corrosive compounds and not desirable. elements in biogas composition are included

A safety equipment list for rotary mode core sampling systems operation in single shell flammable gas tanks

International Nuclear Information System (INIS)

SMALLEY, J.L.

1999-01-01

This document identifies all interim safety equipment to be used for rotary mode core sampling of single-shell flammable gas tanks utilizing Rotary Mode Core Sampling systems (RMCS). This document provides the safety equipment for RMCS trucks HO-68K-4600, HO-68K-4647, trucks three and four respectively, and associated equipment. It is not intended to replace or supersede WHC-SD-WM-SEL-023, (Kelly 1991), or WHC-SD-WM-SEL-032, (Corbett 1994), which classifies 80-68K-4344 and HO-68K-4345 respectively. The term ''safety equipment'' refers to safety class (SC) and safety significant (SS) equipment, where equipment refers to structures, systems and components (SSC's). The identification of safety equipment in this document is based on the credited design safety features and analysis contained in the Authorization Basis (AB) for rotary mode core sampling operations in single-shell flammable gas tanks. This is an interim safety classification since the AB is interim. This document will be updated to reflect the final RMCS equipment safety classification designations upon completion of a final AB which will be implemented with the release of the Final Safety Analysis Report (FSAR)

Resolve. Version 2.5: Flammable Gas Accident Analysis Tool Acceptance Test Plan and Test Results

International Nuclear Information System (INIS)

LAVENDER, J.C.

2000-01-01

RESOLVE. Version 2 .5 is designed to quantify the risk and uncertainty of combustion accidents in double-shell tanks (DSTs) and single-shell tanks (SSTs). The purpose of the acceptance testing is to ensure that all of the options and features of the computer code run; to verify that the calculated results are consistent with each other; and to evaluate the effects of the changes to the parameter values on the frequency and consequence trends associated with flammable gas deflagrations or detonations

Gas generation from radiolytic attack of TRU-contaminated hydrogenous waste

International Nuclear Information System (INIS)

Zerwekh, A.

1979-06-01

In 1970, the Waste Management and Transportation Division of the Atomic Energy Commission ordered a segregation of transuranic (TRU)-contaminated solid wastes. Those below a contamination level of 10 nCi/g could still be buried; those above had to be stored retrievably for 20 y. The possibility that alpha-radiolysis of hydrogenous materials might produce toxic, corrosive, and flammable gases in retrievably stored waste prompted an investigation of gas identities and generation rates in the laboratory and field. Typical waste mixtures were synthesized and contaminated for laboratory experiments, and drums of actual TRU-contaminated waste were instrumented for field testing. Several levels of contamination were studied, as well as pressure, temperature, and moisture effects. G (gas) values were determined for various waste matrices, and degradation products were examined

A safety equipment list for rotary mode core sampling systems operation in single shell flammable gas tanks; TOPICAL

International Nuclear Information System (INIS)

SMALLEY, J.L.

1999-01-01

This document identifies all interim safety equipment to be used for rotary mode core sampling of single-shell flammable gas tanks utilizing Rotary Mode Core Sampling systems (RMCS). This document provides the safety equipment for RMCS trucks HO-68K-4600, HO-68K-4647, trucks three and four respectively, and associated equipment. It is not intended to replace or supersede WHC-SD-WM-SEL-023, (Kelly 1991), or WHC-SD-WM-SEL-032, (Corbett 1994), which classifies 80-68K-4344 and HO-68K-4345 respectively. The term ''safety equipment'' refers to safety class (SC) and safety significant (SS) equipment, where equipment refers to structures, systems and components (SSC's). The identification of safety equipment in this document is based on the credited design safety features and analysis contained in the Authorization Basis (AB) for rotary mode core sampling operations in single-shell flammable gas tanks. This is an interim safety classification since the AB is interim. This document will be updated to reflect the final RMCS equipment safety classification designations upon completion of a final AB which will be implemented with the release of the Final Safety Analysis Report (FSAR)

Gas release during salt well pumping: model predictions and comparisons to laboratory experiments

International Nuclear Information System (INIS)

Peurrung, L.M.; Caley, S.M.; Bian, E.Y.; Gauglitz, P.A.

1996-09-01

The Hanford Site has 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. Some of these wastes are known to generate mixtures of flammable gases, including hydrogen, nitrous oxide, and ammonia. Nineteen of these SSTs have been placed on the Flammable Gas Watch List (FGWL) because they are known or suspected, in all but one case, to retain these flammable gases. Salt well pumping to remove the interstitial liquid from SSTs is expected to cause the release of much of the retained gas, posing a number of safety concerns. Research at the Pacific Northwest National Laboratory (PNNL) has sought to quantify the release of flammable gases during salt well pumping operations. This study is being conducted for Westinghouse Hanford Company as part of the PNNL Flammable Gas Project. Understanding and quantifying the physical mechanisms and waste properties that govern gas release during salt well pumping will help to resolve the associated safety issues

An Equilibrium-Based Model of Gas Reaction and Detonation

International Nuclear Information System (INIS)

Trowbridge, L.D.

2000-01-01

During gaseous diffusion plant operations, conditions leading to the formation of flammable gas mixtures may occasionally arise. Currently, these could consist of the evaporative coolant CFC-114 and fluorinating agents such as F2 and ClF3. Replacement of CFC-114 with a non-ozone-depleting substitute is planned. Consequently, in the future, the substitute coolant must also be considered as a potential fuel in flammable gas mixtures. Two questions of practical interest arise: (1) can a particular mixture sustain and propagate a flame if ignited, and (2) what is the maximum pressure that can be generated by the burning (and possibly exploding) gas mixture, should it ignite? Experimental data on these systems, particularly for the newer coolant candidates, are limited. To assist in answering these questions, a mathematical model was developed to serve as a tool for predicting the potential detonation pressures and for estimating the composition limits of flammability for these systems based on empirical correlations between gas mixture thermodynamics and flammability for known systems. The present model uses the thermodynamic equilibrium to determine the reaction endpoint of a reactive gas mixture and uses detonation theory to estimate an upper bound to the pressure that could be generated upon ignition. The model described and documented in this report is an extended version of related models developed in 1992 and 1999

Action plan for response to abnormal conditions in Hanford high level radioactive liquid waste storage tanks containing flammable gases

International Nuclear Information System (INIS)

Sherwood, D.J.

1994-03-01

Radioactive liquid waste tends to produce hydrogen as a result of the interaction of gamma radiation and water. In tanks containing organic chelating agents, additional hydrogen gas as well as nitrous oxide and ammonia can be produced by thermal and radiolytic decomposition of these organics. Several high-level radioactive liquid waste storage tanks, located underground at the Hanford Site, contain waste that retains the gases produced in them until large quantities are released rapidly to the tank vapor space. Tanks filled to near capacity have relatively little vapor space; therefore, if the waste suddenly releases a large amount of hydrogen and nitrous oxide, a flammable gas mixture may result. The most notable waste tank with a flammable gas problem is tank 241-SY-101. Waste in this tank has occasionally released enough flammable gas to burn if an ignition source had been present inside of the tank. Several other waste tanks exhibit similar behavior to a lesser magnitude. Administrative controls have been developed to assure that these Flammable Gas Watch List tanks are safely maintained. Responses have also been developed for off-normal conditions which might develop in these tanks. In addition, scientific and engineering studies are underway to further understand and mitigate the behavior of the Flammable Gas Watch List tanks

Analysis of flammability in the attached buildings to containment under severe accident conditions

Energy Technology Data Exchange (ETDEWEB)

Rosa, J.C. de la, E-mail: juan-carlos.de-la-rosa-blul@ec.europa.eu [European Commission Joint Research Centre (Netherlands); Fornós, Joan, E-mail: jfornosh@anacnv.com [Asociación Nuclear Ascó-Vandellós (Spain)

2016-11-15

Highlights: • Analysis of flammability conditions in buildings outside containment. • Stepwise approach easily applicable for any kind of containment and attached buildings layout. • Detailed application for real plant conditions has been included. - Abstract: Right after the events unfolded in Fukushima Daiichi, the European Union countries agreed in subjecting Nuclear Power Plants to Stress Tests as developed by WENRA and ENSREG organizations. One of the results as implemented in many European countries derived from such tests consisted of mandatory technical instructions issued by nuclear regulatory bodies on the analysis of potential risk of flammable gases in attached buildings to containment. The current study addresses the key aspects of the analysis of flammable gases leaking to auxiliary buildings attached to Westinghouse large-dry PWR containment for the specific situation where mitigating systems to prevent flammable gases to grow up inside containment are available, and containment integrity is preserved – hence avoiding isolation system failure. It also provides a full practical exercise where lessons learned derived from the current study – hence limited to the imposed boundary conditions – are applied. The leakage of gas from the containment to the support buildings is based on separate calculations using the EPRI-owned Modular Accident Analysis Program, MAAP4.07. The FATE™ code (facility Flow, Aerosol, Thermal, and Explosion) was used to model the transport and distribution of leaked flammable gas (H{sub 2} and CO) in the penetration buildings. FATE models the significant mixing (dilution) which occurs as the released buoyant gas rises and entrains air. Also, FATE accounts for the condensation of steam on room surfaces, an effect which acts to concentrate flammable gas. The results of the analysis show that during a severe accident, flammable conditions are unlikely to occur in compartmentalized buildings such as the one used in the

Analysis of flammability in the attached buildings to containment under severe accident conditions

International Nuclear Information System (INIS)

Rosa, J.C. de la; Fornós, Joan

2016-01-01

Highlights: • Analysis of flammability conditions in buildings outside containment. • Stepwise approach easily applicable for any kind of containment and attached buildings layout. • Detailed application for real plant conditions has been included. - Abstract: Right after the events unfolded in Fukushima Daiichi, the European Union countries agreed in subjecting Nuclear Power Plants to Stress Tests as developed by WENRA and ENSREG organizations. One of the results as implemented in many European countries derived from such tests consisted of mandatory technical instructions issued by nuclear regulatory bodies on the analysis of potential risk of flammable gases in attached buildings to containment. The current study addresses the key aspects of the analysis of flammable gases leaking to auxiliary buildings attached to Westinghouse large-dry PWR containment for the specific situation where mitigating systems to prevent flammable gases to grow up inside containment are available, and containment integrity is preserved – hence avoiding isolation system failure. It also provides a full practical exercise where lessons learned derived from the current study – hence limited to the imposed boundary conditions – are applied. The leakage of gas from the containment to the support buildings is based on separate calculations using the EPRI-owned Modular Accident Analysis Program, MAAP4.07. The FATE™ code (facility Flow, Aerosol, Thermal, and Explosion) was used to model the transport and distribution of leaked flammable gas (H_2 and CO) in the penetration buildings. FATE models the significant mixing (dilution) which occurs as the released buoyant gas rises and entrains air. Also, FATE accounts for the condensation of steam on room surfaces, an effect which acts to concentrate flammable gas. The results of the analysis show that during a severe accident, flammable conditions are unlikely to occur in compartmentalized buildings such as the one used in the

Flammable refrigerants

NARCIS (Netherlands)

Gerwen, R.J.M. van; Verwoerd, M.; Oostendorp, P.A.

1999-01-01

Hydrocarbons are promising alternatives for CFC, HCFC and HFC refrigerants. Due to their flammable nature, safety aspects have to be considered carefully. The world-wide situation concerning acceptability and practical application of flammable refrigerants is becoming more and more complex and

Report on the handling of safety information concerning flammable gases and ferrocyanide at the Hanford waste tanks

International Nuclear Information System (INIS)

1990-07-01

This report discusses concerns safety issues, and management at Hanford Tank Farm. Concerns center on the issue of flammable gas generation which could ignite, and on possible exothermic reactions of ferrocyanide compounds which were added to single shell tanks in the 1950's. It is believed that information concerning these issues has been mis-handled and the problems poorly managed

Report on the handling of safety information concerning flammable gases and ferrocyanide at the Hanford waste tanks

Energy Technology Data Exchange (ETDEWEB)

1990-07-01

This report discusses concerns safety issues, and management at Hanford Tank Farm. Concerns center on the issue of flammable gas generation which could ignite, and on possible exothermic reactions of ferrocyanide compounds which were added to single shell tanks in the 1950's. It is believed that information concerning these issues has been mis-handled and the problems poorly managed. (CBS)

Flammability of kerosene in civil and military aviation

Energy Technology Data Exchange (ETDEWEB)

Sochet, I.; Gillard, P. [Universite d' Orleans, Lab. Energetique Explosions Structures, Bourges cedex, 18 (France)

2002-09-01

The investigation of the ignition conditions of kerosene vapors in the air contained in an aircraft fuel tank contributes to the definition of onboard safety requirements. Civil and military kerosene are characterized by specification. The specification of civil aviation kerosene is based upon usage requirements and property limits, while military kerosene is primarily controlled by specific chemical composition. Characterization of the flammability properties is a first step for the establishment of aircraft safety conditions. Flash point, vapor pressure, gas chromatography analysis, and flammability properties of the kerosene used by the French Military aviation (F-34 and F-35 kerosene) are compared with the flammability properties of civil kerosene. The empirical law established by the Federal Aviation Administration (FAA) in 1998, expressing the ignition energy in terms of fuel, temperature, flash point and altitude is modified and expressed in terms of fuel temperature, flash point and pressure. (Author)

Milestone Report #2: Direct Evaporator Leak and Flammability Analysis Modifications and Optimization of the Organic Rankine Cycle to Improve the Recovery of Waste Heat

Energy Technology Data Exchange (ETDEWEB)

Guillen, Donna Post [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2013-09-01

The direct evaporator is a simplified heat exchange system for an Organic Rankine Cycle (ORC) that generates electricity from a gas turbine exhaust stream. Typically, the heat of the exhaust stream is transferred indirectly to the ORC by means of an intermediate thermal oil loop. In this project, the goal is to design a direct evaporator where the working fluid is evaporated in the exhaust gas heat exchanger. By eliminating one of the heat exchangers and the intermediate oil loop, the overall ORC system cost can be reduced by approximately 15%. However, placing a heat exchanger operating with a flammable hydrocarbon working fluid directly in the hot exhaust gas stream presents potential safety risks. The purpose of the analyses presented in this report is to assess the flammability of the selected working fluid in the hot exhaust gas stream stemming from a potential leak in the evaporator. Ignition delay time for cyclopentane at temperatures and pressure corresponding to direct evaporator operation was obtained for several equivalence ratios. Results of a computational fluid dynamic analysis of a pinhole leak scenario are given.

16 CFR 1500.44 - Method for determining extremely flammable and flammable solids.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Method for determining extremely flammable and flammable solids. 1500.44 Section 1500.44 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS HAZARDOUS SUBSTANCES AND ARTICLES; ADMINISTRATION AND...

Flammable gas safety program. Analytical methods development: FY 1993 progress report

Energy Technology Data Exchange (ETDEWEB)

Campbell, J.A.; Clauss, S.; Grant, K.; Hoopes, V.; Lerner, B.; Lucke, R.; Mong, G.; Rau, J.; Steele, R.

1994-01-01

This report describes the status of developing analytical methods to account for the organic constituents in Hanford waste tanks, with particular emphasis on those tanks that have been assigned to the Flammable Gas Watch List. Six samples of core segments from Tank 101-SY, obtained during the window E core sampling, have been analyzed for organic constituents. Four of the samples were from the upper region, or convective layer, of the tank and two were from the lower, nonconvective layer. The samples were analyzed for chelators, chelator fragments, and several carboxylic acids by derivatization gas chromatography/mass spectrometry (GC/MS). The major components detected were ethylenediaminetetraacetic acid (EDTA), nitroso-iminodiacetic acid (NIDA), nitrilotriacetic acid (NTA), citric acid (CA), succinic acid (SA), and ethylenediaminetriacetic acid (ED3A). The chelator of highest concentration was EDTA in all six samples analyzed. Liquid chromatography (LC) was used to quantitate low molecular weight acids (LMWA) including oxalic, formic, glycolic, and acetic acids, which are present in the waste as acid salts. From 23 to 61% of the total organic carbon (TOC) in the samples analyzed was accounted for by these acids. Oxalate constituted approximately 40% of the TOC in the nonconvective layer samples. Oxalate was found to be approximately 3 to 4 times higher in concentration in the nonconvective layer than in the convective layer. During FY 1993, LC methods for analyzing LWMA, and two chelators N-(2-hydroxyethyl) ethylenediaminetriacetic acid and EDTA, were transferred to personnel in the Analytical Chemistry Laboratory and the 222-S laboratory.

Flammability characteristics of LPG

International Nuclear Information System (INIS)

Cardillo, Paolo

2005-01-01

The use of LPG is continuous increase not only in the domestic field but also in the field of the transports. Consequently, there is a renewed interest for its flammability characteristics in order to decide the necessary conditions of safety. The main components of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG are propane and butane; small concentrations of other hydrocarbons (isobutene, propylene, butane, ethane, pentane) may also be present. Different mixtures of LGP have different and physical characteristics with a different behavior during the use. Also flammability characteristics can be different according to the composition. In this paper at firsts the flammability characteristics of the main components of LGP, taken singularly, are examinated; subsequently some examples of calculation of the flammability limits of different mixture are reported [it

Mechanisms of gas retention and release: Experimental results for Hanford waste tanks 241-AW-101 and 241-AN-103

Energy Technology Data Exchange (ETDEWEB)

Rassat, S.D.; Gauglitz, P.A.; Bredt, P.R.; Mahoney, L.A.; Forbes, S.V.; Tingey, S.M.

1997-09-01

The 177 storage tanks at Hanford contain a vast array of radioactive waste forms resulting, primarily, from nuclear materials processing. Through radiolytic, thermal, and other decomposition reactions of waste components, gaseous species including hydrogen, ammonia, and the oxidizer nitrous oxide are generated within the waste tanks. Many of these tanks are known to retain and periodically release quantities of these flammable gas mixtures. The primary focus of the Flammable Gas Project is the safe storage of Hanford tank wastes. To this end, we strive to develop an understanding of the mechanisms of flammable gas retention and release in Hanford tanks through laboratory investigations on actual tank wastes. These results support the closure of the Flammable Gas Unreviewed Safety Question (USQ) on the safe storage of waste tanks known to retain flammable gases and support resolution of the broader Flammable Gas Safety Issue. The overall purpose of this ongoing study is to develop a comprehensive and thorough understanding of the mechanisms of flammable gas retention and release. The first objective of the current study was to classify bubble retention and release mechanisms in two previously untested waste materials from Tanks 241-AN-103 (AN-103) and 241-AW-101 (AW-101). Results were obtained for retention mechanisms, release characteristics, and the maximum gas retention. In addition, unique behavior was also documented and compared with previously studied waste samples. The second objective was to lengthen the duration of the experiments to evaluate the role of slowing bubble growth on the retention and release behavior. Results were obtained for experiments lasting from a few hours to a few days.

Mechanisms of gas retention and release: Experimental results for Hanford waste tanks 241-AW-101 and 241-AN-103

International Nuclear Information System (INIS)

Rassat, S.D.; Gauglitz, P.A.; Bredt, P.R.; Mahoney, L.A.; Forbes, S.V.; Tingey, S.M.

1997-09-01

The 177 storage tanks at Hanford contain a vast array of radioactive waste forms resulting, primarily, from nuclear materials processing. Through radiolytic, thermal, and other decomposition reactions of waste components, gaseous species including hydrogen, ammonia, and the oxidizer nitrous oxide are generated within the waste tanks. Many of these tanks are known to retain and periodically release quantities of these flammable gas mixtures. The primary focus of the Flammable Gas Project is the safe storage of Hanford tank wastes. To this end, we strive to develop an understanding of the mechanisms of flammable gas retention and release in Hanford tanks through laboratory investigations on actual tank wastes. These results support the closure of the Flammable Gas Unreviewed Safety Question (USQ) on the safe storage of waste tanks known to retain flammable gases and support resolution of the broader Flammable Gas Safety Issue. The overall purpose of this ongoing study is to develop a comprehensive and thorough understanding of the mechanisms of flammable gas retention and release. The first objective of the current study was to classify bubble retention and release mechanisms in two previously untested waste materials from Tanks 241-AN-103 (AN-103) and 241-AW-101 (AW-101). Results were obtained for retention mechanisms, release characteristics, and the maximum gas retention. In addition, unique behavior was also documented and compared with previously studied waste samples. The second objective was to lengthen the duration of the experiments to evaluate the role of slowing bubble growth on the retention and release behavior. Results were obtained for experiments lasting from a few hours to a few days

Mechanisms of gas retention and release: Experimental results for Hanford single-shell waste tanks 241-A-101, 241-S-106, and 241-U-103

International Nuclear Information System (INIS)

Rassat, S.D.; Caley, S.M.; Bredt, P.R.; Gauglitz, P.A.; Rinehart, D.E.; Forbes, S.V.

1998-09-01

The 177 underground waste storage tanks at the Hanford Site contain millions of gallons of radioactive waste resulting from the purification of nuclear materials and related processes. Through various mechanisms, flammable gas mixtures of hydrogen, ammonia, methane, and nitrous oxide are generated and retained in significant quantities within the waste in many (∼25) of these tanks. The potential for large releases of retained gas from these wastes creates a flammability hazard. It is a critical component of the effort to understand the flammability hazard and a primary goal of this laboratory investigation to establish an understanding of the mechanisms of gas retention and release in these wastes. The results of bubble retention experimental studies using waste samples from several waste tanks and a variety of waste types support resolution of the Flammable Gas Safety Issue. Gas bubble retention information gained in the pursuit of safe storage will, in turn, benefit future waste operations including salt-well pumping, waste transfers, and sluicing/retrieval

Composition, preparation, and gas generation results from simulated wastes of Tank 241-SY-101

International Nuclear Information System (INIS)

Bryan, S.A.; Pederson, L.R.

1994-08-01

This document reviews the preparation and composition of simulants that have been developed to mimic the wastes temporarily stored in Tank 241-SY-101 at Hanford. The kinetics and stoichiometry of gases that are generated using these simulants are also compared, considering the roles of hydroxide, chloride, and transition metal ions; the identities of organic constituents; and the effects of dilution, radiation, and temperature. Work described in this report was conducted for the Flammable Gas Safety Program at Pacific Northwest Laboratory, (a) whose purpose is to develop information that is necessary to mitigate potential safety hazards associated with waste tanks at the Hanford Site. The goal of this research and of related efforts at the Georgia Institute of Technology (GIT), Argonne National Laboratory (ANL), and Westinghouse Hanford Company (WHC) is to determine the thermal and thermal/radiolytic mechanisms by which flammable and other gases are produced in Hanford wastes, emphasizing those stored in Tank 241-SY-101. A variety of Tank 241-SY-101 simulants have been developed to date. The use of simulants in laboratory testing activities provides a number of advantages, including elimination of radiological risks to researchers, lower costs associated with experimentation, and the ability to systematically alter simulant compositions to study the chemical mechanisms of reactions responsible for gas generation. The earliest simulants contained the principal inorganic components of the actual waste and generally a single complexant such as N-(2-hydroxyethyl) ethylenediaminetriacetic acid (HEDTA) or ethylenediaminetriacetic acid (EDTA). Both homogeneous and heterogeneous compositional forms were developed. Aggressive core sampling and analysis activities conducted during Windows C and E provided information that was used to design new simulants that more accurately reflected major and minor inorganic components

Position paper on flammability concerns associated with TRU waste destined for WIPP

International Nuclear Information System (INIS)

1991-04-01

The Waste Isolation Pilot Plant (WIPP), in southeastern New Mexico,is an underground repository, designed for the safe geologic disposal of transuranic (TRU) wastes generated from defense-related activities of the US Department of Energy (DOE). The WIPP storage rooms are mined in a bedded salt (halite) formation, and are located 2150 feet below the surface. After the disposal of waste in the storage rooms, closure of the repository is expected to occur by creep (plastic flow) of the salt formation, with the waste being permanently isolated from the surrounding environment. This paper has evaluated the issue of flammability concerns associated with TRU waste to be shipped to WIPP, including a review of possible scenarios that can potentially contribute to the flammability. The paper discusses existing regulations that address potential flammability concerns, presents an analysis of previous flammability-related incidents at DOE sites with respect to the current regulations, and finally, examines the degree of assurance these regulations provide in safeguarding against flammability concerns during transportation and waste handling. 50 refs., 7 figs., 7 tabs

A safety assessment of rotary mode core sampling in flammable gas single shell tanks: Hanford Site, Richland, Washington

Energy Technology Data Exchange (ETDEWEB)

Raymond, R.E.

1996-04-15

This safety assessment (SA) addresses each of the required elements associated with the installation, operation, and removal of a rotary-mode core sampling (RMCS) device in flammable-gas single-shell tanks (SSTs). The RMCS operations are needed in order to retrieve waste samples from SSTs with hard layers of waste for which push-mode sampling is not adequate for sampling. In this SA, potential hazards associated with the proposed action were identified and evaluated systematically. Several potential accident cases that could result in radiological or toxicological gas releases were identified and analyzed and their consequences assessed. Administrative controls, procedures and design changes required to eliminate or reduce the potential of hazards were identified. The accidents were analyzed under nine categories, four of which were burn scenarios. In SSTS, burn accidents result in unacceptable consequences because of a potential dome collapse. The accidents in which an aboveground burn propagates into the dome space were shown to be in the ``beyond extremely unlikely`` frequency category. Given the unknown nature of the gas-release behavior in the SSTS, a number of design changes and administrative controls were implemented to achieve these low frequencies. Likewise, drill string fires and dome space fires were shown to be very low frequency accidents by taking credit for the design changes, controls, and available experimental and analytical data. However, a number of Bureau of Mines (BOM) tests must be completed before some of the burn accidents can be dismissed with high confidence. Under the category of waste fires, the possibility of igniting the entrapped gases and the waste itself were analyzed. Experiments are being conducted at the BOM to demonstrate that the drill bit is not capable of igniting the trapped gas in the waste. Laboratory testing and thermal analysis demonstrated that, under normal operating conditions, the drill bit will not create high

A safety assessment of rotary mode core sampling in flammable gas single shell tanks: Hanford Site, Richland, Washington

International Nuclear Information System (INIS)

Raymond, R.E.

1996-01-01

This safety assessment (SA) addresses each of the required elements associated with the installation, operation, and removal of a rotary-mode core sampling (RMCS) device in flammable-gas single-shell tanks (SSTs). The RMCS operations are needed in order to retrieve waste samples from SSTs with hard layers of waste for which push-mode sampling is not adequate for sampling. In this SA, potential hazards associated with the proposed action were identified and evaluated systematically. Several potential accident cases that could result in radiological or toxicological gas releases were identified and analyzed and their consequences assessed. Administrative controls, procedures and design changes required to eliminate or reduce the potential of hazards were identified. The accidents were analyzed under nine categories, four of which were burn scenarios. In SSTS, burn accidents result in unacceptable consequences because of a potential dome collapse. The accidents in which an aboveground burn propagates into the dome space were shown to be in the ''beyond extremely unlikely'' frequency category. Given the unknown nature of the gas-release behavior in the SSTS, a number of design changes and administrative controls were implemented to achieve these low frequencies. Likewise, drill string fires and dome space fires were shown to be very low frequency accidents by taking credit for the design changes, controls, and available experimental and analytical data. However, a number of Bureau of Mines (BOM) tests must be completed before some of the burn accidents can be dismissed with high confidence. Under the category of waste fires, the possibility of igniting the entrapped gases and the waste itself were analyzed. Experiments are being conducted at the BOM to demonstrate that the drill bit is not capable of igniting the trapped gas in the waste. Laboratory testing and thermal analysis demonstrated that, under normal operating conditions, the drill bit will not create high

Analysis of flammability limits for the liquefaction process of oxygen-bearing coal-bed methane

International Nuclear Information System (INIS)

Li, Q.Y.; Wang, L.; Ju, Y.L.

2011-01-01

Highlights: → A novel liquefaction and distillation process is designed for oxygen bearing coal-bed methane. → Oxygen contained in coal-bed methane is removed in distillation process. → Flammability limits are analyzed for the whole operation process. → We find explosion hazard may exist in distillation tower. → Effective measures are proposed to ensure the operation safety in distillation tower. - Abstract: A novel liquefaction and distillation process has been proposed and designed for the typical oxygen-bearing coal-bed methane (CBM), in which the impurities of the oxygen and nitrogen components are removed in the distillation column. The flammability limit theory combining with HYSYS simulation results are employed to analyze and calculate the flammability limits and the results indicate that no flammability hazard exists in the stages of compression, liquefaction and throttling. However, flammability hazard exists at the top the distillation column because the methane mole fraction decreases to the value below the upper flammability limit (UFL). The safety measures of initially removing oxygen content from the feed gas combining with the control of the bottom flowrate (flowrate of the liquid product at column bottom) are proposed to ensure the operation safety of the liquefaction process. The results reveal that the operation safety of the whole process can be guaranteed, together with high methane recovery rate and high purity of the liquid product. The applicability of the liquefaction process has also been analyzed in this paper. The simulation results can offer references for the separation of oxygen from CBM, the analysis of flammability limits and the safety measures for the whole process.

Summary report on the design of the retained gas sampler system (retained gas sampler, extruder and extractor)

International Nuclear Information System (INIS)

Wootan, D.W.; Bolden, R.C.; Bridges, A.E.; Cannon, N.S.; Chastain, S.A.; Hey, B.E.; Knight, R.C.; Linschooten, C.G.; Pitner, A.L.; Webb, B.J.

1994-01-01

This document summarizes work performs in Fiscal Year 1994 to develop the three main components of Retained Gas Sampler System (RGSS). These primary components are the Retained Gas Sampler (RGS), the Retained Gas Extruder (RGE), and the Retained Gas Extractor (RGEx). The RGS is based on the Westinghouse Hanford Company (WHC) Universal Sampler design, and includes modifications to reduce gas leakage. The primary data priorities for the RGSS are to measure the void fraction and the flammable gas concentration in the waste sample. Significant progress has been made in developing the RGSS. The RGSS is being developed by WHC to extract a representative waste sample from a Flammable Gas Watch List Tanks and to measure both the amount and composition of free and open-quotes boundclose quotes gases. Sudden releases of flammable gas mixtures are a safety concern for normal waste storage operations and eventual waste retrieval. Flow visualization testing was used to identify important fluid dynamic issues related to the sampling process. The primary data priorities for the RGSS are to measure the void fraction and the flammable gas concentration in the waste sample. The safety analysis for the RGSS is being performed by Los Alamos National Laboratory and is more than sixty percent (60%) complete

Evaluation of Gas Retention in Waste Simulants: Tall Column Experiments

Energy Technology Data Exchange (ETDEWEB)

Schonewill, Philip P.; Gauglitz, Phillip A.; Shimskey, Rick W.; Denslow, Kayte M.; Powell, Michael R.; Boeringa, Gregory K.; Bontha, Jagannadha R.; Karri, Naveen K.; Fifield, Leonard S.; Tran, Diana N.; Sande, Susan; Heldebrant, David J.; Meacham, Joseph E.; Smet, Dave; Bryan, Wesley E.; Calmus, Ronald B.

2014-05-16

Gas generation in Hanford’s underground waste storage tanks can lead to gas accumulation within the layer of settled solids (sludge) at the tank bottom. The gas, which typically has hydrogen as the major component together with other flammable species, is formed principally by radiation-driven chemical reactions. Accumulation of these gases within the sludge in a waste tank is undesirable and limits the amount of tank volume for waste storage. Further, accumulation of large amounts of gas in the sludge may potentially result in an unacceptable release of the accumulated gas if the sludge-layer density is reduced to less than that of the overlying sludge or that of the supernatant liquid. Rapid release of large amounts of flammable gases could endanger personnel and equipment near the tank. For this reason, a thorough understanding of the circumstances that can lead to a potentially problematic gas accumulation in sludge layers is needed. To respond to this need, the Deep Sludge Gas Release Event Program (DSGREP) was commissioned to examine gas release behavior in sludges.

Mechanisms of gas bubble retention and release: results for Hanford Waste Tanks 241-S-102 and 241-SY-103 and single-shell tank simulants

Energy Technology Data Exchange (ETDEWEB)

Gauglitz, P.A.; Rassat, S.D.; Bredt, P.R.; Konynenbelt, J.H.; Tingey, S.M.; Mendoza, D.P.

1996-09-01

Research at Pacific Northwest National Laboratory (PNNL) has probed the physical mechanisms and waste properties that contribute to the retention and release of flammable gases from radioactive waste stored in underground tanks at Hanford. This study was conducted for Westinghouse Hanford Company as part of the PNNL Flammable Gas Project. The wastes contained in the tanks are mixes of radioactive and chemical products, and some of these wastes are known to generate mixtures of flammable gases, including hydrogen, nitrous oxide, and ammonia. Because these gases are flammable, their retention and episodic release pose a number of safety concerns.

Mechanisms of gas bubble retention and release: results for Hanford Waste Tanks 241-S-102 and 241-SY-103 and single-shell tank simulants

International Nuclear Information System (INIS)

Gauglitz, P.A.; Rassat, S.D.; Bredt, P.R.; Konynenbelt, J.H.; Tingey, S.M.; Mendoza, D.P.

1996-09-01

Research at Pacific Northwest National Laboratory (PNNL) has probed the physical mechanisms and waste properties that contribute to the retention and release of flammable gases from radioactive waste stored in underground tanks at Hanford. This study was conducted for Westinghouse Hanford Company as part of the PNNL Flammable Gas Project. The wastes contained in the tanks are mixes of radioactive and chemical products, and some of these wastes are known to generate mixtures of flammable gases, including hydrogen, nitrous oxide, and ammonia. Because these gases are flammable, their retention and episodic release pose a number of safety concerns

16 CFR 1500.45 - Method for determining extremely flammable and flammable contents of self-pressurized containers.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Method for determining extremely flammable and flammable contents of self-pressurized containers. 1500.45 Section 1500.45 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS HAZARDOUS SUBSTANCES AND...

75 FR 49379 - Correction to Internal Citation of “Extremely Flammable Solid” and “Flammable Solid”

Science.gov (United States)

2010-08-13

... CONSUMER PRODUCT SAFETY COMMISSION 16 CFR Part 1500 Correction to Internal Citation of ``Extremely... to correct internal citations to the definitions of ``extremely flammable solid'' and ``flammable... citation for part 1500 continues to read as follows: Authority: 15 U.S.C. 1261-1277. 0 2. In Sec. 1500.83...

FLAMMABILITY OF HERBICIDE-TREATED GUAVA FOLIAGE

Science.gov (United States)

Guava leaves treated with herbicide were found to be less flammable than untreated green leaves or dead leaves . Differences in flammability were...determined by small-scale laboratory fires, differential thermal analysis, and thermogravimetric analysis. The herbicide-treated leaves had a higher ash

16 CFR 423.9 - Conflict with flammability standards.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Conflict with flammability standards. 423.9... TEXTILE WEARING APPAREL AND CERTAIN PIECE GOODS AS AMENDED § 423.9 Conflict with flammability standards. If there is a conflict between this regulation and any regulations issued under the Flammable Fabrics...

TECHNICAL JUSTIFICATION FOR CHOOSING PROPANE AS A CALIBRATION AGENT FOR TOTAL FLAMMABLE VOLATILE ORGANIC COMPOUND (VOC) DETERMINATIONS

International Nuclear Information System (INIS)

DOUGLAS, J.G.

2006-01-01

This document presents the technical justification for choosing and using propane as a calibration standard for estimating total flammable volatile organic compounds (VOCs) in an air matrix. A propane-in-nitrogen standard was selected based on a number of criteria: (1) has an analytical response similar to the VOCs of interest, (2) can be made with known accuracy and traceability, (3) is available with good purity, (4) has a matrix similar to the sample matrix, (5) is stable during storage and use, (6) is relatively non-hazardous, and (7) is a recognized standard for similar analytical applications. The Waste Retrieval Project (WRP) desires a fast, reliable, and inexpensive method for screening the flammable VOC content in the vapor-phase headspace of waste containers. Table 1 lists the flammable VOCs of interest to the WRP. The current method used to determine the VOC content of a container is to sample the container's headspace and submit the sample for gas chromatography--mass spectrometry (GC-MS) analysis. The driver for the VOC measurement requirement is safety: potentially flammable atmospheres in the waste containers must be allowed to diffuse prior to processing the container. The proposed flammable VOC screening method is to inject an aliquot of the headspace sample into an argon-doped pulsed-discharge helium ionization detector (Ar-PDHID) contained within a gas chromatograph. No actual chromatography is performed; the sample is transferred directly from a sample loop to the detector through a short, inert transfer line. The peak area resulting from the injected sample is proportional to the flammable VOC content of the sample. However, because the Ar-PDHID has different response factors for different flammable VOCs, a fundamental assumption must be made that the agent used to calibrate the detector is representative of the flammable VOCs of interest that may be in the headspace samples. At worst, we desire that calibration with the selected calibrating

The effect of the environment conditions on the prediction of flammable cloud dispersion

OpenAIRE

Schleder, Adriana; Martins, Marcelo; Pastor Ferrer, Elsa; Planas Cuchi, Eulàlia

2014-01-01

In order to quantify the damage caused by undesired events involving leakages of flammable materials, specific models are used to analyze the spills or jets of gas and liquid, gas dispersion, explosions and fires. The main step of this analysis is to estimate the concentration, in space and time, of the vapor cloud of hazardous substances released into the atmosphere; the purpose is to determine the area where a fire or explosion might occur and the quantity of flam...

A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

International Nuclear Information System (INIS)

Mendoza, D.P.; Mahoney, L.A.; Gauglitz, P.A.; Rassat, S.D.; Caley, S.M.

1999-01-01

The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the volume of gas released was sufficient to exceed the lower flammability limit (LFL) in the tank headspace (Alleinann et al. 1993). A mixer pump was installed in SY-101 in late 1993 to prevent gases from building up in the settled solids layer, and the large episodic gas releases have since ceased (Allemann et al. 1994; Stewart et al. 1994; Brewster et al. 1995). However, the surface level of SY-101 has been increasing since at least 1995, and in recent months the level growth has shown significant and unexpected acceleration. Based on a number of observations and measurements, including data from the void fraction instrument (VFI), we have concluded that the level growth is caused largely by increased gas retention in the floating crust. In September 1998, the crust contained between about 21 and 43% void based on VFI measurements (Stewart et al. 1998). Accordingly, it is important to understand the dominant mechanisms of gas retention, why the gas retention is increasing, and whether the accelerating level increase will continue, diminish or even reverse. It is expected that the retained gas in the crust is flammable, with hydrogen as a major constituent. This gas inventory would pose a flammable gas hazard if it were to release suddenly. In May 1997, the mechanisms of bubble retention and release from crust material were the subject of a workshop. The evaluation of the crust and potential hazards assumed a more typical void of roughly 15% gas. It could be similar to

A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

Energy Technology Data Exchange (ETDEWEB)

SD Rassat; PA Gauglitz; SM Caley; LA Mahoney; DP Mendoza

1999-02-23

The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the volume of gas released was sufficient to exceed the lower flammability limit (LFL) in the tank headspace (Allemann et al. 1993). A mixer pump was installed in SY-101 in late 1993 to prevent gases from building up in the settled solids layer, and the large episodic gas releases have since ceased (Allemann et al. 1994; Stewart et al. 1994; Brewster et al. 1995). However, the surface level of SY-101 has been increasing since at least 1995, and in recent months the level growth has shown significant and unexpected acceleration. Based on a number of observations and measurements, including data from the void fraction instrument (VFI), we have concluded that the level growth is caused largely by increased gas retention in the floating crust. In September 1998, the crust contained between about 21 and 43% void based on VFI measurements (Stewart et al. 1998). Accordingly, it is important to understand the dominant mechanisms of gas retention, why the gas retention is increasing, and whether the accelerating level increase will continue, diminish or even reverse. It is expected that the retained gas in the crust is flammable, with hydrogen as a major constituent. This gas inventory would pose a flammable gas hazard if it were to release suddenly. In May 1997, the mechanisms of bubble retention and release from crust material were the subject of a workshop. The evaluation of the crust and potential hazards assumed a more typical void of roughly 15% gas. It could be similar to

Predicting the flammable region reach of propane vapor clouds

OpenAIRE

Vílchez Sánchez, Juan Antonio; Villafañe, Diana; Casal Fàbrega, Joaquim

2014-01-01

Liquified gas fuels are widely used around the world, and the growth of LNG and LPG consumption continues to increase. However, using these fuels can lead to accidents if they are released to the environment. Consequently, the challenge to control and predict such hazards has become an objective in emergency planning and risk analysis. In a previous article the “Dispersion Safety Factor” (DSF) was proposed, defined as the ratio between the distance at which the lower flammability limit concen...

Natural gas for utility generation

International Nuclear Information System (INIS)

Moore, T.

1992-01-01

Forecasters predict that natural gas will be the dominant fuel choice for utility capacity additions in the coming decade and that power generation will be by far the largest growth market for gas sales. While gas's low emissions, high efficiency potential, and present low cost argue persuasively for a surge in gas-fired generation, many utilities have been slow to commit to a gas future, citing reasoned concern about long-term price trends and the ability of gas suppliers to deliver the fuel where and when it will be needed. Meanwhile, the relatively low cost of gas-fired units is providing an opportunity for independent power producers to compete strongly with utilities for generation contracts. EPRI studies suggest that a sound, competitive strategy will be based not on how much gas a utility burns, but rather on how this capacity fits into its overall generating mix at various fuel price levels. Gas suppliers will need to pay special attention to the operating needs of power generators if they are to solidify this important market

A study on flammability limits of fuel mixtures.

Science.gov (United States)

Kondo, Shigeo; Takizawa, Kenji; Takahashi, Akifumi; Tokuhashi, Kazuaki; Sekiya, Akira

2008-07-15

Flammability limit measurements were made for various binary and ternary mixtures prepared from nine different compounds. The compounds treated are methane, propane, ethylene, propylene, methyl ether, methyl formate, 1,1-difluoroethane, ammonia, and carbon monoxide. The observed values of lower flammability limits of mixtures were found to be in good agreement to the calculated values by Le Chatelier's formula. As for the upper limits, however, some are close to the calculated values but some are not. It has been found that the deviations of the observed values of upper flammability limits from the calculated ones are mostly to lower concentrations. Modification of Le Chatelier's formula was made to better fit to the observed values of upper flammability limits. This procedure reduced the average difference between the observed and calculated values of upper flammability limits to one-third of the initial value.

Tank 241-C-103 headspace flammability

International Nuclear Information System (INIS)

Huckaby, J.L.

1994-01-01

Information regarding flammable vapors, gases, and aerosols is presented for the purpose of resolving the tank 241-C-103 headspace flammability issue. Analyses of recent vapor and liquid samples, as well as visual inspections of the tank headspace, are discussed in the context of tank dynamics. This document is restricted to issues regarding the flammability of gases, vapors, and an aerosol that may exist in the headspace of tank 241-C-103. While discussing certain information about the organic liquid present in tank 241-C-103, this document addresses neither the potential for, nor consequences of, a pool fire involving this organic liquid; they will be discussed in a separate report

Tank 241-C-103 headspace flammability

Energy Technology Data Exchange (ETDEWEB)

Huckaby, J.L.

1994-01-01

Information regarding flammable vapors, gases, and aerosols is presented for the purpose of resolving the tank 241-C-103 headspace flammability issue. Analyses of recent vapor and liquid samples, as well as visual inspections of the tank headspace, are discussed in the context of tank dynamics. This document is restricted to issues regarding the flammability of gases, vapors, and an aerosol that may exist in the headspace of tank 241-C-103. While discussing certain information about the organic liquid present in tank 241-C-103, this document addresses neither the potential for, nor consequences of, a pool fire involving this organic liquid; they will be discussed in a separate report.

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Extremely flammable contact adhesives... REGULATIONS § 1500.133 Extremely flammable contact adhesives; labeling. (a) Extremely flammable contact adhesives, also known as contact bonding cements, when distributed in containers intended or suitable for...

Evaluation of Gas Retention in Waste Simulants: Intermediate-Scale Column and Open-Channel-Depth Tests

Energy Technology Data Exchange (ETDEWEB)

Powell, Michael R.; Gauglitz, Phillip A.; Denslow, Kayte M.; Fischer, Christopher M.; Heldebrant, David J.; Prowant, Matthew S.; Sande, Susan; Davis, James M.; Telander, Monty R.

2014-02-14

Gas generation in Hanford’s radioactive waste storage tanks can lead to gas accumulation within the layer of settled solids (sludge) at the tank bottom. The gas, which may be hazardous and/or flammable, is formed principally by radiation-driven chemical reactions. Accumulation of these gases within the sludge increases the sludge-layer volume, which decreases the available tank volume for waste storage. Further, accumulation of large amounts of gas in the sludge can potentially result in a relatively rapid release of the accumulated gas if the sludge-layer density is reduced to less than that of the overlying sludge or that of the supernatant liquid. The potential for rapid release of large amounts of hazardous and/or flammable gases is a safety hazard that needs to be managed. Accordingly, a thorough understanding is needed of the circumstances that can lead to problematic gas accumulation in sludge layers. The Deep-Sludge Gas Release Event Project (DSGREP) is tasked with developing an improved understanding of these gas release events.

16 CFR 1611.4 - Flammability test.

Science.gov (United States)

2010-01-01

... FLAMMABILITY OF VINYL PLASTIC FILM The Standard § 1611.4 Flammability test. (a) Apparatus and materials. The.... The center section of the rack contains an open U-shaped area in which burning of the specimen takes... fan is turned off during the test. (4) Timing mechanism. The burning rate shall be determined by a...

Genetic component of flammability variation in a Mediterranean shrub.

Science.gov (United States)

Moreira, B; Castellanos, M C; Pausas, J G

2014-03-01

Recurrent fires impose a strong selection pressure in many ecosystems worldwide. In such ecosystems, plant flammability is of paramount importance because it enhances population persistence, particularly in non-resprouting species. Indeed, there is evidence of phenotypic divergence of flammability under different fire regimes. Our general hypothesis is that flammability-enhancing traits are adaptive; here, we test whether they have a genetic component. To test this hypothesis, we used the postfire obligate seeder Ulex parviflorus from sites historically exposed to different fire recurrence. We associated molecular variation in potentially adaptive loci detected with a genomic scan (using AFLP markers) with individual phenotypic variability in flammability across fire regimes. We found that at least 42% of the phenotypic variation in flammability was explained by the genetic divergence in a subset of AFLP loci. In spite of generalized gene flow, the genetic variability was structured by differences in fire recurrence. Our results provide the first field evidence supporting that traits enhancing plant flammability have a genetic component and thus can be responding to natural selection driven by fire. These results highlight the importance of flammability as an adaptive trait in fire-prone ecosystems. © 2014 John Wiley & Sons Ltd.

Understanding vented gas explosions

Energy Technology Data Exchange (ETDEWEB)

Lautkaski, R. [VTT Energy, Espoo (Finland). Energy Systems

1997-12-31

The report is an introduction to vented gas explosions for nonspecialists, particularly designers of plants for flammable gases and liquids. The phenomena leading to pressure generation in vented gas explosions in empty and congested rooms are reviewed. The four peak model of vented gas explosions is presented with simple methods to predict the values of the individual peaks. Experimental data on the external explosion of dust and gas explosions is discussed. The empirical equation relating the internal and external peak pressures in vented dust explosions is shown to be valid for gas explosion tests in 30 m{sup 3} and 550 m{sup 3} chambers. However, the difficulty of predicting the internal peak pressure in large chambers remains. Methods of explosion relief panel design and principles of vent and equipment layout to reduce explosion overpressures are reviewed. (orig.) 65 refs.

Understanding vented gas explosions

Energy Technology Data Exchange (ETDEWEB)

Lautkaski, R [VTT Energy, Espoo (Finland). Energy Systems

1998-12-31

The report is an introduction to vented gas explosions for nonspecialists, particularly designers of plants for flammable gases and liquids. The phenomena leading to pressure generation in vented gas explosions in empty and congested rooms are reviewed. The four peak model of vented gas explosions is presented with simple methods to predict the values of the individual peaks. Experimental data on the external explosion of dust and gas explosions is discussed. The empirical equation relating the internal and external peak pressures in vented dust explosions is shown to be valid for gas explosion tests in 30 m{sup 3} and 550 m{sup 3} chambers. However, the difficulty of predicting the internal peak pressure in large chambers remains. Methods of explosion relief panel design and principles of vent and equipment layout to reduce explosion overpressures are reviewed. (orig.) 65 refs.

Gas bubble retention and its effect on waste properties: Retention mechanisms, viscosity, and tensile and shear strengths

International Nuclear Information System (INIS)

Gauglitz, P.A.; Rassat, S.D.; Powell, M.R.

1995-08-01

Several of the underground nuclear storage tanks at Hanford have been placed on a flammable gas watch list, because the waste is either known or suspected to generate, store, and episodically release flammable gases. Because retention and episodic release of flammable gases from these tanks containing radioactive waste slurries are critical safety concerns, Pacific Northwest Laboratory (PNL) is studying physical mechanisms and waste properties that contribute to the episodic gas release from these storage tanks. This study is being conducted for Westinghouse Hanford Company as part of the PNL Flammable Gas project. Previous investigations have concluded that gas bubbles are retained by the slurry or sludge that has settled at the bottom of the tanks; however, the mechanisms responsible for the retention of these bubbles are not well understood. Understanding the rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles and the dynamics of how these bubbles are released from the waste. The presence of gas bubbles is expected to affect the rheology of the sludge, specifically its viscosity and tensile and shear strengths, but essentially no literature data are available to assess the effect of bubbles. The objectives of this study were to conduct experiments and develop theories to understand better how bubbles are retained by slurries and sludges, to measure the effect of gas bubbles on the viscosity of simulated slurries, and to measure the effect of gas bubbles on the tensile and shear strengths of simulated slurries and sludges. In addition to accomplishing these objectives, this study developed correlations, based on the new experimental data, that can be used in large-scale computations of waste tank physical phenomena

Gas bubble retention and its effect on waste properties: Retention mechanisms, viscosity, and tensile and shear strengths

Energy Technology Data Exchange (ETDEWEB)

Gauglitz, P.A.; Rassat, S.D.; Powell, M.R. [and others

1995-08-01

Several of the underground nuclear storage tanks at Hanford have been placed on a flammable gas watch list, because the waste is either known or suspected to generate, store, and episodically release flammable gases. Because retention and episodic release of flammable gases from these tanks containing radioactive waste slurries are critical safety concerns, Pacific Northwest Laboratory (PNL) is studying physical mechanisms and waste properties that contribute to the episodic gas release from these storage tanks. This study is being conducted for Westinghouse Hanford Company as part of the PNL Flammable Gas project. Previous investigations have concluded that gas bubbles are retained by the slurry or sludge that has settled at the bottom of the tanks; however, the mechanisms responsible for the retention of these bubbles are not well understood. Understanding the rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles and the dynamics of how these bubbles are released from the waste. The presence of gas bubbles is expected to affect the rheology of the sludge, specifically its viscosity and tensile and shear strengths, but essentially no literature data are available to assess the effect of bubbles. The objectives of this study were to conduct experiments and develop theories to understand better how bubbles are retained by slurries and sludges, to measure the effect of gas bubbles on the viscosity of simulated slurries, and to measure the effect of gas bubbles on the tensile and shear strengths of simulated slurries and sludges. In addition to accomplishing these objectives, this study developed correlations, based on the new experimental data, that can be used in large-scale computations of waste tank physical phenomena.

Gas supply planning for new gas-fired electricity generation facilities

International Nuclear Information System (INIS)

Slocum, J.C.

1990-01-01

This paper explores several key issues in gas supply planning for new gas fired electric generation facilities. This paper will have two main sections, as follows: developing the gas supply plan for a gas-fired electricity generation facility and exploring key gas supply contract pricing issues

An Approach to the Flammability Testing of Aerospace Materials

Science.gov (United States)

Hirsch, David B.

2012-01-01

Presentation reviews: (1) Current approach to evaluation of spacecraft materials flammability (2) The need for and the approach to alternative routes (3) Examples of applications of the approach recommended a) Crew Module splash down b) Crew Module depressurization c) Applicability of NASA's flammability test data to other sample configurations d) Applicability of NASA's ground flammability test data to spacecraft environments

10 CFR 36.69 - Irradiation of explosive or flammable materials.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Irradiation of explosive or flammable materials. 36.69... IRRADIATORS Operation of Irradiators § 36.69 Irradiation of explosive or flammable materials. (a) Irradiation... cause radiation overexposures of personnel. (b) Irradiation of more than small quantities of flammable...

Independent design review report for truck number 1 modifications for flammable gas tanks

International Nuclear Information System (INIS)

Wilson, G.W.

1997-01-01

The East and West Tank Farm Standing Order 97-01 requires that the PMST be modified to include purging of the enclosed space underneath the shielded receiver weather cover per National Fire Protection Association (NFPA) 496, Purged and Pressurized Enclosures for Electrical Equipment. The Standing Order also requires that the PMST be modified by replacing the existing electrical remote latch (RLU) unit with a mechanical remote latch unit. As the mechanical remote latch unit was exactly like the RLU installed on the Rotary Mode Core Sampler Trucks (RMCST) and the design for the RMCST went through formal design review, replacing the RLU was done utilizing informal design verification and was completed per work package ES-97-0028. As the weather cover purge was similar to the design for the RMCSTS, this design was reviewed using the independent review method with multiple independent reviewers. A function design criteria (WHC-SD-WM-FDC-048, Functional Design Criteria for Core Sampling in Flammable Gas Watch List Tanks) provided the criteria for the modifications. The review consisted of distributing the design review package to the reviewers and collecting and dispositioning the RCR comments. The review package included the ECNs for review, the Design Compliance Matrix, copies of all drawings affected, and copies of outstanding ECNs against these drawings. A final meeting was held to ensure that all reviewers were aware of the changes to ECNs from incorporation of RCR comments

The effect of the computational grid size on the prediction of a flammable cloud dispersion

OpenAIRE

Schleder, Adriana; Martins, Marcelon; Pastor Ferrer, Elsa; Planas Cuchi, Eulàlia

2014-01-01

The consequence analysis is used to define the extent and nature of effects caused by undesired events being of great help when quantifying the damage caused by such events. For the case of leaking of flammable and/or toxic materials, effects are analyzed for explosions, fires and toxicity. Specific models are used to analyze the spills or jets of gas or liquids, gas dispersions, explosions and fires. The central step in the analysis of consequences in such cases is to de...

Gas retention and release behavior in Hanford single-shell waste tanks

International Nuclear Information System (INIS)

Stewart, C.W.; Brewster, M.E.; Gauglitz, P.A.; Mahoney, L.A.; Meyer, P.A.; Recknagle, K.P.; Reid, H.C.

1996-12-01

This report describes the current understanding of flammable gas retention and release in Hanford single-shell waste tanks based on theory, experimental results, and observations of tank behavior. The single-shell tanks likely to pose a flammable gas hazard are listed and described, and photographs of core extrusions and the waste surface are included. The credible mechanisms for significant flammable gas releases are described, and release volumes and rates are quantified as much as possible. The only mechanism demonstrably capable of producing large (∼100 m 3 ) spontaneous gas releases is the buoyant displacement, which occurs only in tanks with a relatively deep layer of supernatant liquid. Only the double-shell tanks currently satisfy this condition. All release mechanisms believed plausible in single-shell tanks have been investigated, and none have the potential for large spontaneous gas releases. Only small spontaneous gas releases of several cubic meters are likely by these mechanisms. The reasons several other postulated gas release mechanisms are implausible or incredible are also given

Bubble retention in synthetic sludge: Testing of alternative gas retention apparatus

International Nuclear Information System (INIS)

Rassat, S.D.; Gauglitz, P.A.

1995-07-01

Several of the underground storage tanks currently used to store waste at Hanford have been placed on the Flammable Gas Watch List, because the waste is either known or suspected to generate, store, and episodically release flammable gases. The objective of this experimental study is to develop a method to measure gas bubble retention in simulated tank waste and in diluted simulant. The method and apparatus should (1) allow for reasonably rapid experiments, (2) minimize sample disturbance, and (3) provide realistic bubble nucleation and growth. The scope of this experimental study is to build an apparatus for measuring gas retention in simulated waste and to design the apparatus to be compatible with future testing on actual waste. The approach employed for creating bubbles in sludge involves dissolving a soluble gas into the supernatant liquid at an elevated pressure, recirculating the liquid containing the dissolved gas through the sludge, then reducing the pressure to allow bubbles to nucleate and grow. Results have been obtained for ammonia as the soluble gas and SY1-SIM-91A, a chemically representative simulated tank waste. In addition, proof-of-principle experiments were conducted with both ammonia and CO 2 as soluble gases and sludge composed of 90-micron glass beads. Results are described

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

International Nuclear Information System (INIS)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-01

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

Energy Technology Data Exchange (ETDEWEB)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-29

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

On the temperature dependence of flammability limits of gases.

Science.gov (United States)

Kondo, Shigeo; Takizawa, Kenji; Takahashi, Akifumi; Tokuhashi, Kazuaki

2011-03-15

Flammability limits of several combustible gases were measured at temperatures from 5 to 100 °C in a 12-l spherical flask basically following ASHRAE method. The measurements were done for methane, propane, isobutane, ethylene, propylene, dimethyl ether, methyl formate, 1,1-difluoroethane, ammonia, and carbon monoxide. As the temperature rises, the lower flammability limits are gradually shifted down and the upper limits are shifted up. Both the limits shift almost linearly to temperature within the range examined. The linear temperature dependence of the lower flammability limits is explained well using a limiting flame temperature concept at the lower concentration limit (LFL)--'White's rule'. The geometric mean of the flammability limits has been found to be relatively constant for many compounds over the temperature range studied (5-100 °C). Based on this fact, the temperature dependence of the upper flammability limit (UFL) can be predicted reasonably using the temperature coefficient calculated for the LFL. However, some compounds such as ethylene and dimethyl ether, in particular, have a more complex temperature dependence. Copyright © 2011 Elsevier B.V. All rights reserved.

14 CFR 26.37 - Pending type certification projects: Fuel tank flammability.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pending type certification projects: Fuel tank flammability. 26.37 Section 26.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... AIRPLANES Fuel Tank Flammability § 26.37 Pending type certification projects: Fuel tank flammability. (a...

Framing scenarios of electricity generation and gas use: EPRI report series on gas demands for power generation. Final report

International Nuclear Information System (INIS)

Thumb, S.; Glover, W.; Hughes, W.R.

1996-07-01

Results of three EPRI projects have been combined to analyze power industry consumption of gas and other generating fuels. The report's capstone is a scenario analysis of power industry generation and fuel consumption. The Utility Fuel Consumption Model (UFCM), developed for the project, predicts generating capacity and generation by region and fuel through 2015, based on load duration curves, generation dispatch, and expected capacity additions. Scenarios embody uncertain factors, such as electricity demand growth, fuel switching, coal-gas competition, the merit order of gas-coal dispatch, and retirement of nuclear units, that substantially affect gas consumption. Some factors, especially electricity demand have very large effects. The report includes a consistent database on NUG (non-utility generation) capacity and generation and assesses historical and prospective trends in NUG generation. The report shows that NUG capacity growth will soon decline substantially. The study assesses industry capability for price-induced fuel switching from gas to oil and coal, documenting conversions of coal units to dual coal-gas capability and determining that gas-to-oil switching remains a strong influence on fuel availability and gas prices, though regulation and taxation have increased trigger prices for switching. 61 tabs

A highly conductive, non-flammable polymer–nanoparticle hybrid electrolyte

KAUST Repository

Agrawal, Akanksha; Choudhury, Snehashis; Archer, Lynden A.

2015-01-01

liquid media as the electrolyte solvent. Remarkably, we also find that even in highly flammable liquid media, the bidisperse nanoparticle hybrid electrolytes can be formulated to exhibit low or no flammability without compromising their favorable room

Gas retention and release behavior in Hanford single-shell waste tanks

Energy Technology Data Exchange (ETDEWEB)

Stewart, C.W.; Brewster, M.E.; Gauglitz, P.A.; Mahoney, L.A.; Meyer, P.A.; Recknagle, K.P.; Reid, H.C.

1996-12-01

This report describes the current understanding of flammable gas retention and release in Hanford single-shell waste tanks based on theory, experimental results, and observations of tank behavior. The single-shell tanks likely to pose a flammable gas hazard are listed and described, and photographs of core extrusions and the waste surface are included. The credible mechanisms for significant flammable gas releases are described, and release volumes and rates are quantified as much as possible. The only mechanism demonstrably capable of producing large ({approximately}100 m{sup 3}) spontaneous gas releases is the buoyant displacement, which occurs only in tanks with a relatively deep layer of supernatant liquid. Only the double-shell tanks currently satisfy this condition. All release mechanisms believed plausible in single-shell tanks have been investigated, and none have the potential for large spontaneous gas releases. Only small spontaneous gas releases of several cubic meters are likely by these mechanisms. The reasons several other postulated gas release mechanisms are implausible or incredible are also given.

14 CFR Appendix M to Part 25 - Fuel Tank System Flammability Reduction Means

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel Tank System Flammability Reduction... 25—Fuel Tank System Flammability Reduction Means M25.1Fuel tank flammability exposure requirements. (a) The Fleet Average Flammability Exposure of each fuel tank, as determined in accordance with...

Method of burning flammable radioactive wastes

International Nuclear Information System (INIS)

Yahata, Taneaki.

1980-01-01

Purpose: To completely oxidize flammable radioactive wastes such as organic compounds, ion exchange materials or oils. Method: Contaminated flammable radioactive wastes are heated and pyrolytically decomposed in the range 400 0 to 500 0 C in the presence of oxygen under lower pressure than atmospheric pressure. Volatile organic substance, hydrogen and soot subsequently produced are passed over oxidation catalyst. The catalysts such as copper oxide, iron oxide, cobalt oxide, nickel oxide, chromium oxide are heated in the range 600 0 to 700 0 C to produce stable oxides. (J.P.N.)

METHODOLOGY & CALCULATIONS FOR THE ASSIGNMENT OF WASTE FOR THE LARGE UNDERGROUND WASTE STORAGE TANKS AT THE HANFORD SITE

Energy Technology Data Exchange (ETDEWEB)

TU, T.A.

2007-01-04

Waste stored within tank farm double-shell tanks (DST) and single-shell tanks (SST) generates flammable gas (principally hydrogen) to varying degrees depending on the type, amount, geometry, and condition of the waste. The waste generates hydrogen through the radiolysis of water and organic compounds, thermolytic decomposition of organic compounds, and corrosion of a tank's carbon steel walls. Radiolysis and thermolytic decomposition also generates ammonia. Nonflammable gases, which act as dilutents (such as nitrous oxide), are also produced. Additional flammable gases (e.g., methane) are generated by chemical reactions between various degradation products of organic chemicals present in the tanks. Volatile and semi-volatile organic chemicals in tanks also produce organic vapors. The generated gases in tank waste are either released continuously to the tank headspace or are retained in the waste matrix. Retained gas may be released in a spontaneous or induced gas release event (GRE) that can significantly increase the flammable gas concentration in the tank headspace as described in RPP-7771, Flammable Gas Safety Isme Resolution. Appendices A through I provide supporting information. The document categorizes each of the large waste storage tanks into one of several categories based on each tank's waste and characteristics. These waste group assignments reflect a tank's propensity to retain a significant volume of flammable gases and the potential of the waste to release retained gas by a buoyant displacement event. Revision 6 is the annual update of the flammable gas Waste Groups for DSTs and SSTs.

A Simple Technique to Estimate the Flammability Index of Moroccan Forest Fuels

Directory of Open Access Journals (Sweden)

M'Hamed Hachmi

2011-01-01

Full Text Available A formula to estimate forest fuel flammability index (FI is proposed, integrating three species flammability parameters: time to ignition, time of combustion, and flame height. Thirty-one (31 Moroccan tree and shrub species were tested within a wide range of fuel moisture contents. Six species flammability classes were identified. An ANOVA of the FI-values was performed and analyzed using four different sample sizes of 12, 24, 36, and 50 flammability tests. Fuel humidity content is inversely correlated to the FI-value, and the linear model appears to be the most adequate equation that may predict the hypothetical threshold-point of humidity of extinction. Most of the Moroccan forest fuels studied are classified as moderately flammable to flammable species based on their average humidity content, calculated for the summer period from July to September.

Off-gas characteristics of defense waste vitrification using liquid-fed Joule-heated ceramic melters

International Nuclear Information System (INIS)

Goles, R.W.; Sevigny, G.J.

1983-09-01

Off-gas and effluent characterization studies have been established as part of a PNL Liquid-Fed Ceramic Melter development program supporting the Savannah River Laboratory Defense Waste Processing Facility (SRL-DWPF). The objectives of these studies were to characterize the gaseous and airborne emission properties of liquid-fed joule-heated melters as a function of melter operational parameters and feed composition. All areas of off-gas interest and concern including effluent characterization, emission control, flow rate behavior and corrosion effects have been studied using alkaline and formic-acid based feed compositions. In addition, the behavioral patterns of gaseous emissions, the characteristics of melter-generated aerosols and the nature and magnitude of melter effluent losses have been established under a variety of feeding conditions with and without the use of auxiliary plenum heaters. The results of these studies have shown that particulate emissions are responsible for most radiologically important melter effluent losses. Melter-generated gases have been found to be potentially flammable as well as corrosive. Hydrogen and carbon monoxide present the greatest flammability hazard of the combustibles produced. Melter emissions of acidic volatile compounds of sulfur and the halogens have been responsible for extensive corrosion observed in melter plenums and in associated off-gas lines and processing equipment. The use of auxiliary plenum heating has had little effect upon melter off-gas characteristics other than reducing the concentrations of combustibles

Gas in electricity generation [In New Zealand

International Nuclear Information System (INIS)

Devine, K.

1995-01-01

Gas is New Zealand's major thermal fuel for electricity generation. This paper describes what influences the volumes of gas burnt by ECNZ, and forecasts future gas demands for electricity generation. It also reviews the uncertainties associated with these forecasts and likely competition in building new electricity generating stations and outlines the strategy now being formulated to accommodate them. Because ECNZ's generation system is hydro-based, relatively small rapid changes in hydrological conditions can significantly affect the amount of gas used. This situation will change over time with major increases in thermal generation likely to be needed over the next 20 years. However, there are considerable uncertainties on gas supply and electricity demand levels in the long run, which will complicate investment and fuel decisions. (Author)

Flammable gas production in Land 2 and Land 3/4 radioactive waste repositories

International Nuclear Information System (INIS)

1988-02-01

Geological, radiolytic and microbiological sources of gas are considered in relation to Land 2 and Land 3/4 type radioactive waste repositories. Geological sources are potentially the most troublesome and it is concluded that site investigation work should be designed to detect gas trap structures, reservoir lithologies or source rocks. Known source and reservoir lithologies should not be considered as suitable for the siting of waste repositories. Radiolytic and microbiological sources will depend on waste characteristics. A detailed review of the literature on radiolytic gas generation is presented and conclusions from this work indicate that water in waste and matrix should be kept to a minimum. Similarly, the level of radioactivity stored in each waste container should be kept to the minimum compatible with the storage design. Microbiological gas sources will be reduced by maintaining the cellulose content of the waste at a minimum. It is suggested that the removal of organics from the waste stream would be beneficial in terms of potential gas production. (author)

Centralized power generation: what share for gas?

International Nuclear Information System (INIS)

Honore, A.; Pharabod, E.; Lecointe, O.; Poyer, L.

2007-01-01

Up to a recent past, most energy scenarios were foreseeing a fast growth of natural gas consumption thanks to an assumed strong penetration of gas-fueled power plants. The share of natural gas in the centralized power generation has been the subject of a meeting of the French gas association (AFG) which aimed at answering the following questions: today's position of gas power generation in Europe in the present day context of gas prices (level, volatility), the share of natural gas in the French power mix in the coming years, the strategies of development of gas power plants by historical operators and newcomers, the gas arbitration between its sale to end-users and its use for power generation, and the integration of the CO 2 risk. (J.S.)

Signal generation in gas detectors

International Nuclear Information System (INIS)

Stillman, A.

1993-01-01

This tutorial describes the generation of electrical signals in gas detectors. Ionization of the gas by the passage of charged particles generates these signals. Starting with the Bethe-Bloch equation, the treatment is a general introduction to the production of ion-pairs in gas devices. I continue with the characterization of the ionization as an electrical signal, and calculate the signal current in a simple example. Another example demonstrates the effect of space charge on the design of a detector. The AGS Booster ionization profile monitor is a model for this calculation

Gas characterization system software acceptance test procedure

International Nuclear Information System (INIS)

Vo, C.V.

1996-01-01

This document details the Software Acceptance Testing of gas characterization systems. The gas characterization systems will be used to monitor the vapor spaces of waste tanks known to contain measurable concentrations of flammable gases

Gas retention and release behavior in Hanford double-shell waste tanks

Energy Technology Data Exchange (ETDEWEB)

Meyer, P.A.; Brewster, M.E.; Bryan, S.A. [and others

1997-05-01

This report describes the current understanding of flammable gas retention and release in Hanford double-shell waste tanks AN-103, AN-104, AN-105, AW-101, SY-101, and SY-103. This knowledge is based on analyses, experimental results, and observations of tank behavior. The applicable data available from the void fraction instrument, retained gas sampler, ball rheometer, tank characterization, and field monitoring are summarized. Retained gas volumes and void fractions are updated with these new data. Using the retained gas compositions from the retained gas sampler, peak dome pressures during a gas burn are calculated as a function of the fraction of retained gas hypothetically released instantaneously into the tank head space. Models and criteria are given for gas generation, initiation of buoyant displacement, and resulting gas release; and predictions are compared with observed tank behavior.

Gas retention and release behavior in Hanford double-shell waste tanks

International Nuclear Information System (INIS)

Meyer, P.A.; Brewster, M.E.; Bryan, S.A.

1997-05-01

This report describes the current understanding of flammable gas retention and release in Hanford double-shell waste tanks AN-103, AN-104, AN-105, AW-101, SY-101, and SY-103. This knowledge is based on analyses, experimental results, and observations of tank behavior. The applicable data available from the void fraction instrument, retained gas sampler, ball rheometer, tank characterization, and field monitoring are summarized. Retained gas volumes and void fractions are updated with these new data. Using the retained gas compositions from the retained gas sampler, peak dome pressures during a gas burn are calculated as a function of the fraction of retained gas hypothetically released instantaneously into the tank head space. Models and criteria are given for gas generation, initiation of buoyant displacement, and resulting gas release; and predictions are compared with observed tank behavior

Tank 24-C-103 headspace flammability

International Nuclear Information System (INIS)

Huckaby, J.L.

1994-05-01

Information regarding flammable vapors, gases, and aerosols is presented and interpreted to help resolve the tank 241-C-103 headspace flammability issue. Analyses of recent vapor and liquid samples, as well as visual inspections of the tank headspace, are discussed in the context of tank dynamics. Concern that the headspace of tank 241-C-103 may contain a flammable mixture of organic vapors and an aerosol of combustible organic liquid droplets arises from the presence of a layer of organic liquid in the tank. This organic liquid is believed to have originated in the plutonium-uranium extraction (PUREX) process, having been stored initially in tank 241-C-102 and apparently transferred to tank 241-C-103 in 1975 (Carothers 1988). Analyses of samples of the organic liquid collected in 1991 and 1993 indicate that the primary constituents are tributyl phosphate (TBP) and several semivolatile hydrocarbons (Prentice 1991, Pool and Bean 1994). This is consistent with the premise that the organic waste came from the PUREX process, because the PUREX process used a solution of TBP in a diluent composed of the n-C 11 H 24 to n-C 15 H 32 normal paraffinic hydrocarbons (NPH)

49 CFR 174.304 - Class 3 (flammable liquid) materials in tank cars.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Class 3 (flammable liquid) materials in tank cars... (flammable liquid) materials in tank cars. A tank car containing a Class 3 (flammable liquid) material, other... the liquid from the tank car to permanent storage tanks of sufficient capacity to receive the entire...

A study of transient flow turbulence generation during flame/wall interactions in explosions

Science.gov (United States)

Hargrave, G. K.; Jarvis, S.; Williams, T. C.

2002-07-01

Experimental data are presented for the turbulent velocity field generated during flame/solid wall interactions in explosions. The presence of turbulence in a flammable gas mixture can wrinkle a flame front, increasing the flame surface area and enhancing the burning rate. In congested process plant, any flame propagating through an accidental release of flammable mixture will encounter obstructions in the form of walls, pipe-work or storage vessels. The interaction between the gas movement and the obstacle creates turbulence by vortex shedding and local wake/recirculation, whereby the flame can be wrapped in on itself, increasing the surface area available for combustion. Particle image velocimetry (PIV) was used to characterize the turbulent flow field in the wake of the obstacles placed in the path of propagating flames. This allowed the quantification of the interaction of the propagating flame and the generated turbulent flow field. Due to the accelerating nature of the explosion flow field, the wake flows develop `transient' turbulent fields and PIV provided data to define the spatial and temporal variation of the velocity field ahead of the propagating flame, providing an understanding of the direct interaction between flow and flame.

Gas characterization system software acceptance test report

International Nuclear Information System (INIS)

Vo, C.V.

1996-01-01

This document details the results of software acceptance testing of gas characterization systems. The gas characterization systems will be used to monitor the vapor spaces of waste tanks known to contain measurable concentrations of flammable gases

Flammability tests for regulation of building and construction materials

Science.gov (United States)

K. Sumathipala

2006-01-01

The regulation of building materials and products for flammability is critical to ensure the safety of occupants in buildings and other structures. The involvement of exposed building materials and products in fires resulting in the loss of human life often spurs an increase in regulation and new test methods to address the problem. Flammability tests range from those...

Flammability of litter from southeastern trees: a preliminary assessment

Science.gov (United States)

J. Morgan Varner; Jeffrey M. Kane; Erin M. Banwell; Jesse K. Kreye

2015-01-01

The southeastern United States possesses a great diversity of woody species and an equally impressive history of wildland fires. Species are known to vary in their flammability, but little is known about southeastern species. We used published data and our own collections to perform standard litter flammability tests on a diverse suite of 25 native overstory trees from...

METHODOLOGY & CALCULATIONS FOR THE ASSIGNMENT OF WASTE GROUPS FOR THE LARGE UNDERGROUND WASTE STORAGE TANKS AT THE HANFORD SITE

Energy Technology Data Exchange (ETDEWEB)

BARKER, S.A.

2006-07-27

Waste stored within tank farm double-shell tanks (DST) and single-shell tanks (SST) generates flammable gas (principally hydrogen) to varying degrees depending on the type, amount, geometry, and condition of the waste. The waste generates hydrogen through the radiolysis of water and organic compounds, thermolytic decomposition of organic compounds, and corrosion of a tank's carbon steel walls. Radiolysis and thermolytic decomposition also generates ammonia. Nonflammable gases, which act as dilutents (such as nitrous oxide), are also produced. Additional flammable gases (e.g., methane) are generated by chemical reactions between various degradation products of organic chemicals present in the tanks. Volatile and semi-volatile organic chemicals in tanks also produce organic vapors. The generated gases in tank waste are either released continuously to the tank headspace or are retained in the waste matrix. Retained gas may be released in a spontaneous or induced gas release event (GRE) that can significantly increase the flammable gas concentration in the tank headspace as described in RPP-7771. The document categorizes each of the large waste storage tanks into one of several categories based on each tank's waste characteristics. These waste group assignments reflect a tank's propensity to retain a significant volume of flammable gases and the potential of the waste to release retained gas by a buoyant displacement event. Revision 5 is the annual update of the methodology and calculations of the flammable gas Waste Groups for DSTs and SSTs.

21 CFR 866.2580 - Gas-generating device.

Science.gov (United States)

2010-04-01

...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2580 Gas-generating device. (a) Identification. A gas-generating device is a device intended for medical purposes that produces...

Cracked gas generator

Energy Technology Data Exchange (ETDEWEB)

Abthoff, J; Schuster, H D; Gabler, R

1976-11-17

A small cracked-gas generator in a vehicle driven, in particular, by an air combustion engine has been proposed for the economic production of the gases necessary for low toxicity combustion from diesel fuel. This proceeds via catalytic crack-gasification and exploitation of residual heat from exhaust gases. This patent application foresees the insertion of one of the catalysts supporting the cracked-gas reaction in a container through which the reacting mixture for cracked-gas production flows in longitudinal direction. Further, air ducts are embedded in the catalyst through which exhaust gases and fresh air flow in counter direction to the cracked gas flow in the catalyst. The air vents are connected through heat conduction to the catalyst. A cracked gas constituting H/sub 2//CO/CO/sub 2//CH/sub 4/ and H/sub 2/O can be produced from the air-fuel mixture using appropriate catalysts. By the addition of 5 to 25% of cracked gas to the volume of air drawn in by the combustion engine, a more favourable combustion can be achieved compared to that obtained under normal combustion conditions.

Flammability on textile of flight crew professional clothing

Science.gov (United States)

Silva-Santos, M. C.; Oliveira, M. S.; Giacomin, A. M.; Laktim, M. C.; Baruque-Ramos, J.

2017-10-01

The issue about flammability of textile materials employed in passenger cabins of commercial aircrafts is an important part of safety routines planning. Once an in-flight emergency initiated with fire or smoke aboard, time becomes critical and the entire crew must be involved in the solution. It is part of the crew functions, notably the attendants, the in-flight firefighting. This study compares the values of textile material of flight attendant working cloths and galley curtain fabric with regard to flammability and Limiting Oxygen Index (LOI). Values to the professional clothing material indicate that they are flammable and the curtains, self-extinguishing. Thus, despite of the occurrences of fire outbreaks in aircrafts are unexceptional, the use of other materials and technologies for uniforms, such as alternative textile fibers and flame retardant finishes should be considered as well as the establishment of performance limits regarding flame and fire exposing.

14 CFR 26.39 - Newly produced airplanes: Fuel tank flammability.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Newly produced airplanes: Fuel tank... Tank Flammability § 26.39 Newly produced airplanes: Fuel tank flammability. (a) Applicability: This... Series 767 Series (b) Any fuel tank meeting all of the criteria stated in paragraphs (b)(1), (b)(2) and...

Gas generation in incinerator ash; Gasbildning i aska

Energy Technology Data Exchange (ETDEWEB)

Arm, Maria; Lindeberg, Johanna; Rodin, Aasa; Oehrstroem, Anna; Backman, Rainer; Oehman, Marcus; Bostroem, Dan

2006-02-15

In recent years, explosions have occurred in certain phases of ash handling in Sweden. Investigations have revealed that hydrogen may have been present in all cases. The hydrogen is believed to be generated by chemical reactions of aluminium and other metals within the ash in the presence of water. The purpose with this study is to increase the knowledge of gas generation of incinerator ash. Thereby, guides for appropriate ash management can be introduced and the risk for further explosions prevented. The study has comprised analyses of the ash properties, such as chemical and physical composition and the pH, of ash from 14 incineration plants (mostly waste incineration plants). Different fractions of ash materials representing different parts of the process in each plant have been analysed. Furthermore, the fuel and the technical differences between the plants have been analysed. A tool for measuring the gas generation in the laboratory has been developed and the gas generation of the different ash materials at natural and increased pH was measured. Gas analyses and thermodynamic calculations have also been performed. The results showed that: bottom ash from fluidised bed boilers generated small amounts of gas at increased pH, much smaller amounts than the idle pass, cyclone and filter ash did, bottom ash from grate fired boilers generated more gas at increased pH than their cyclone ash and filter ash, with exception of the Linkoeping plant, all bio waste incineration plants generated ash with low gas generation potential, all fly ash materials with a gas generation potential of more than 10 l/kg originated from municipal waste incineration plants, filter ash that had been stored in oxygen rich environment generated significant less gas than fresh filter ash of the same origin, hardly any other gases were generated apart from hydrogen (very small amounts of acetone, furane, benzene and most likely methane were detected in some of the ash materials), there were no

Modelling leaf, plant and stand flammability for ecological and operational decision making

Science.gov (United States)

Zylstra, Philip

2014-05-01

Numerous factors have been found to affect the flammability of individual leaves and plant parts; however the way in which these factors relate to whole plant flammability, fire behaviour and the overall risk imposed by fire is not straightforward. Similarly, although the structure of plant communities is known to affect the flammability of the stand, a quantified, broadly applicable link has proven difficult to establish and validate. These knowledge gaps have presented major obstacles to the integration into fire behaviour science of research into factors affecting plant flammability, physiology, species succession and structural change, so that the management of ecosystems for fire risk is largely uninformed by these fields. The Forest Flammability Model (Zylstra, 2011) is a process-driven, complex systems model developed specifically to address this disconnect. Flame dimensions and position are calculated as properties emerging from the capacity for convective heat to propagate flame between horizontally and vertically separated leaves, branches, plants and plant strata, and this capacity is determined dynamically from the ignitability, combustibility and sustainability of those objects, their spatial arrangement and a vector-based model of the plume temperature from each burning fuel. All flammability properties as well as the physics of flame dimensions, angle and temperature distributions and the vertical structure of wind within the plant array use published sub-models which can be replaced as further work is developed. This modular structure provides a platform for the immediate application of new work on any aspect of leaf flammability or fire physics. Initial validation of the model examined its qualitative predictions for trends in forest flammability as a function of time since fire. The positive feedback predicted for the subalpine forest examined constituted a 'risky prediction' by running counter to the expectations of the existing approach, however

Integration of the Uncertainties of Anion and TOC Measurements into the Flammability Control Strategy for Sludge Batch 8 at the DWPF

International Nuclear Information System (INIS)

Edwards, T. B.

2013-01-01

The Savannah River National Laboratory (SRNL) has been working with the Savannah River Remediation (SRR) Defense Waste Processing Facility (DWPF) in the development and implementation of a flammability control strategy for DWPF's melter operation during the processing of Sludge Batch 8 (SB8). SRNL's support has been in response to technical task requests that have been made by SRR's Waste Solidification Engineering (WSE) organization. The flammability control strategy relies on measurements that are performed on Slurry Mix Evaporator (SME) samples by the DWPF Laboratory. Measurements of nitrate, oxalate, formate, and total organic carbon (TOC) standards generated by the DWPF Laboratory are presented in this report, and an evaluation of the uncertainties of these measurements is provided. The impact of the uncertainties of these measurements on DWPF's strategy for controlling melter flammability also is evaluated. The strategy includes monitoring each SME batch for its nitrate content and its TOC content relative to the nitrate content and relative to the antifoam additions made during the preparation of the SME batch. A linearized approach for monitoring the relationship between TOC and nitrate is developed, equations are provided that integrate the measurement uncertainties into the flammability control strategy, and sample calculations for these equations are shown to illustrate the impact of the uncertainties on the flammability control strategy

Estimation of the lower flammability limit of organic compounds as a function of temperature.

Science.gov (United States)

Rowley, J R; Rowley, R L; Wilding, W V

2011-02-15

A new method of estimating the lower flammability limit (LFL) of general organic compounds is presented. The LFL is predicted at 298 K for gases and the lower temperature limit for solids and liquids from structural contributions and the ideal gas heat of formation of the fuel. The average absolute deviation from more than 500 experimental data points is 10.7%. In a previous study, the widely used modified Burgess-Wheeler law was shown to underestimate the effect of temperature on the lower flammability limit when determined in a large-diameter vessel. An improved version of the modified Burgess-Wheeler law is presented that represents the temperature dependence of LFL data determined in large-diameter vessels more accurately. When the LFL is estimated at increased temperatures using a combination of this model and the proposed structural-contribution method, an average absolute deviation of 3.3% is returned when compared with 65 data points for 17 organic compounds determined in an ASHRAE-style apparatus. Copyright © 2010 Elsevier B.V. All rights reserved.

Controlling the ignition and flammability of magnesium for aerospace applications

International Nuclear Information System (INIS)

Czerwinski, Frank

2014-01-01

The perceived easy ignition and flammability of magnesium alloys create a detrimental safety feature that overshadows their high strength-to-weight ratio and hinders the aerospace application opportunities. To overcome the existing barriers a progress in understanding and controlling the reactivity of magnesium at high temperatures is required. This report describes fundamentals of magnesium ignition and flammability along with laboratory testing procedures and correlations with full scale fire scenarios, related in particular to the aircraft cabin. The influence of alloying elements on high temperature reactivity of magnesium and global efforts to develop ignition resistant and non-flammable magnesium alloys are reviewed. Although ignition and flammability represent quite different quantities, both are controlled by an oxidation resistance of the alloy and its capability to form a dense and protective surface oxide after exposures to an open flame or other heat source. Since surface oxide, composed of pure MgO, does not offer a sufficient protection, the research strategy is focused on modification of its chemistry and microstructure by micro-alloying the substrate with rare earths and other elements having high affinity to oxygen

The effect of dilution on the gas retention behavior of Tank 241-SY- 103 waste

International Nuclear Information System (INIS)

Bredt, P.R.; Tingey, S.M.

1996-01-01

Twenty-five of the 177 underground waste storage tanks on the Hanford Site have been placed on the Flammable Gas watch list. These 25 tanks, containing high-level waste generated during plutonium and uranium processing, have been identified as potentially capable of accumulating flammable gases above the lower flammability limit (Babad et al. 1991). In the case of Tanks 241-SY-101 and 241-SY-103, it has been proposed that diluting the tank waste may mitigate this hazard (Hudson et al. 1995; Stewart et al. 1994). The effect of dilution on the ability of waste from Tank 241-SY-103 to accumulate gas was studied at Pacific Northwest National Laboratory. A similar study has been completed for waste from Tank 241-SY-101 (Bredt et al. 1995). Because of the additional waste-storage volume available in Tank 241-SY-103 and because the waste is assumed to be similar to that currently in Tank 241-SY-101, Tank 241-SY-103 became the target for a demonstration of passive mitigation through in-tank dilution. In 1994, plans for the in-tank dilution demonstration were deferred pending a decision on whether to pursue dilution as a mitigation strategy. However, because Tank 241-SY-103 is an early retrieval target, determination of how waste properties vary with dilution will still be required

Gas Detection for Experiments

CERN Document Server

Hay, D

2001-01-01

Flammable gases are often used in detectors for physics experiments. The storage, distribution and manipulation of such flammable gases present several safety hazards. As most flammable gases cannot be detected by human senses, specific well-placed gas detection systems must be installed. Following a request from the user group and in collaboration with CERN safety officers, risk analyses are performed. An external contractor, who needs to receive detailed user requirements from CERN, performs the installations. The contract is passed on a guaranteed results basis. Co-ordination between all the CERN groups and verification of the technical installation is done by ST/AA/AS. This paper describes and focuses on the structured methodology applied to implement such installations based on goal directed project management techniques (GDPM). This useful supervision tool suited to small to medium sized projects facilitates the task of co-ordinating numerous activities to achieve a completely functional system.

Wireless gas sensing in South African underground platinum mines

CSIR Research Space (South Africa)

Abu-Mahfouz, Adnan M

2014-04-01

Full Text Available Approximately 70% of South African mines are classified as fiery, where methane gas potentially could cause explosions. The number of flammable gas reports and accidents are increasing steadily for both gold and platinum mines. However...

Gas turbine electric generator

International Nuclear Information System (INIS)

Nemoto, Masaaki; Yuhara, Tetsuo.

1993-01-01

When troubles are caused to a boundary of a gas turbine electric generator, there is a danger that water as an operation medium for secondary circuits leaks to primary circuits, to stop a plant and the plant itself can not resume. Then in the present invention, helium gases are used as the operation medium not only for the primary circuits but also for the secondary circuits, to provide so-called a direct cycle gas turbine system. Further, the operation media of the primary and secondary circuits are recycled by a compressor driven by a primary circuit gas turbine, and the turbine/compressor is supported by helium gas bearings. Then, problems of leakage of oil and water from the bearings or the secondary circuits can be solved, further, the cooling device in the secondary circuit is constituted as a triple-walled tube structure by way of helium gas, to prevent direct leakage of coolants into the reactor core even if cracks are formed to pipes. (N.H.)

Gas generation from transuranic waste degradation: an interim assessment

International Nuclear Information System (INIS)

Molecke, M.A.

1979-10-01

A review of all available, applicable data pertaining to gas generation from the degradation of transuranic waste matrix material and packaging is presented. Waste forms are representative of existing defense-related TRU wastes and include cellulosics, plastics, rubbers, concrete, process sludges, and mild steel. Degradation mechanisms studied were radiolysis, thermal, bacterial, and chemical corrosion. Gas generation rates are presented in terms of moles of gas produced per year per drum, and in G(gas) values for radiolytic degradation. Comparison of generation rates is made, as is a discussion of potential short- and long-term concerns. Techniques for reducing gas generation rates are discussed. 6 figures, 10 tables

Gas-fired electric power generating technologies

International Nuclear Information System (INIS)

1994-09-01

The workshop that was held in Madrid 25-27 May 1994 included participation by experts from 16 countries. They represented such diverse fields and disciplines as technology, governmental regulation, economics, and environment. Thus, the participants provided an excellent cross section of key areas and a diversity of viewpoints. At the workshop, a broad range of topics regarding gas-fired electric power generation was discussed. These included political, regulatory and financial issues as well as more specific technical questions regarding the environment, energy efficiency, advanced generation technologies and the status of competitive developments. Important technological advances in gas-based power and CHP technologies have already been achieved including higher energy efficiency and lower emissions, with further improvements expected in the near future. Advanced technology trends include: (a) The use of gas technology to reduce emissions from existing coal-fired power plants. (b) The wide-spread application of combined-cycle gas turbines in new power plants and the growing use of aero-derivative gas turbines in CHP applications. (c) Phosphoric acid fuel cells that are being introduced commercially. Their market penetration will grow over the next 10 years. The next generation of fuel cells (solid oxide and molten carbonate) is expected to enter the market around the year 2000. (EG)

Natural gas and electricity generation in Queensland

International Nuclear Information System (INIS)

Webb, G.

2001-01-01

The focus of this article is on electricity generation in Queensland. Black coal accounted for 97 percent, while natural gas made up only 1 percent of the fuel used in thermal power generation in 1997-98. The share of natural gas in thermal electricity generation is expected to rise to 21 percent by 2014-2015, because of the emphasis on natural gas in Queensland's new energy policy. Since 1973-1974, Queensland has led the way in electricity consumption, with an average annual growth rate of 6.8 percent but the average thermal efficiency has fallen from 38.0 percent in 1991-1992, to 36.6 percent in 1997-1998

Development of the Raman lidar system for remote hydrogen gas detection

Energy Technology Data Exchange (ETDEWEB)

Choi, In Young; Baik, Sung Hoon; Park, Seung Kyu; Park, Nak Gyu; Choi, Young Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Detection of hydrogen (H{sub 2}) gas leakage is very important for safety of the nuclear power plant because H{sub 2} gas is very flammable and explosive. H{sub 2} gas is generated by oxidizing the nuclear fuel cladding during the critical accident and generated H{sub 2} gas leads to serious secondary damages in the containment building of nuclear power plant. Thus, various H{sub 2} gas detection techniques are used in the nuclear power plant such as catalytic combustion sensors, semiconducting oxide sensors, thermal conductivity sensors and electrochemical sensor. A Raman lidar (Light Detection And Ranging) system for remote detection of the H{sub 2} gas can cover the area in the containment building of a nuclear power plant. H{sub 2} gas has a very strong Raman Effect, and H{sub 2} Raman cells have been widely used for laser wavelength conversion. In this study, Raman lidar system was developed for H{sub 2} gas detection used in the containment building of nuclear power plant. In this study, remote hydrogen gas detection devices and measuring algorithm are developed by using the Raman lidar method. Through the experiment, we proved that our developed Raman lidar system was possible to measure the N{sub 2} and H{sub 2} gas scattering signal remotely.

Extended Le Chatelier's formula for carbon dioxide dilution effect on flammability limits.

Science.gov (United States)

Kondo, Shigeo; Takizawa, Kenji; Takahashi, Akifumi; Tokuhashi, Kazuaki

2006-11-02

Carbon dioxide dilution effect on the flammability limits was measured for various flammable gases. The obtained values were analyzed using the extended Le Chatelier's formula developed in a previous study. As a result, it has been found that the flammability limits of methane, propane, propylene, methyl formate, and 1,1-difluoroethane are adequately explained by the extended Le Chatelier's formula using a common set of parameter values. Ethylene, dimethyl ether, and ammonia behave differently from these compounds. The present result is very consistent with what was obtained in the case of nitrogen dilution.

Inherently safe passive gas monitoring system

Energy Technology Data Exchange (ETDEWEB)

Cordaro, Joseph V.; Bellamy, John Stephen; Shuler, James M.; Shull, Davis J.; Leduc, Daniel R.

2016-09-06

Generally, the present disclosure is directed to gas monitoring systems that use inductive power transfer to safely power an electrically passive device included within a nuclear material storage container. In particular, the electrically passive device can include an inductive power receiver for receiving inductive power transfer through a wall of the nuclear material storage container. The power received by the inductive power receiver can be used to power one or more sensors included in the device. Thus, the device is not required to include active power generation components such as, for example, a battery, that increase the risk of a spark igniting flammable gases within the container.

Seasonal and local differences in leaf litter flammability of six Mediterranean tree species.

Science.gov (United States)

Kauf, Zorica; Fangmeier, Andreas; Rosavec, Roman; Španjol, Željko

2015-03-01

One of the suggested management options for reducing fire danger is the selection of less flammable plant species. Nevertheless, vegetation flammability is both complex and dynamic, making identification of such species challenging. While large efforts have been made to connect plant traits to fire behavior, seasonal changes and within species variability of traits are often neglected. Currently, even the most sophisticated fire danger systems presume that intrinsic characteristics of leaf litter stay unchanged, and plant species flammability lists are often transferred from one area to another. In order to assess if these practices can be improved, we performed a study examining the relationship between morphological characteristics and flammability parameters of leaf litter, thereby taking into account seasonal and local variability. Litter from six Mediterranean tree species was sampled throughout the fire season from three different locations along a climate gradient. Samples were subjected to flammability testing involving an epiradiator operated at 400 °C surface temperature with 3 g sample weight. Specific leaf area, fuel moisture content, average area, and average mass of a single particle had significant influences on flammability parameters. Effects of sampling time and location were significant as well. Due to the standardized testing conditions, these effects could be attributed to changes in intrinsic characteristics of the material. As the aforementioned effects were inconsistent and species specific, these results may potentially limit the generalization of species flammability rankings. Further research is necessary in order to evaluate the importance of our findings for fire danger modeling.

Modelling gas generation in radioactive waste repositories

International Nuclear Information System (INIS)

Agg, P.J.

1993-02-01

In a repository containing low- and intermediate-level waste, gas generation will occur principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. This Paper describes a mathematical model design to address gas generation by these mechanisms. The metal corrosion model incorporates a three-stage process encompassing both aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. Gas concentrations have been measured over a period of three years in large-scale drum experiments designed to simulate repository conditions. Model predictions are confirmed against the experimental measurements, and a prediction is then made of gas concentrations and generation rates over an assessment period of one million years in a radioactive waste repository. (author)

Modelling gas generation in radioactive waste repositories

International Nuclear Information System (INIS)

Agg, P.J.

1992-07-01

In a repository containing low- and intermediate-level waste, gas generation will occur principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. This paper describes a mathematical model designed to address gas generation by these mechanisms. The metal corrosion model incorporates a three-stage process encompassing both aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. Gas concentrations have been measured over a period of three years in large-scale drum experiments designed to simulate repository conditions. Model predictions are confirmed against the experimental measurements, and a prediction is then made of gas concentrations and generation rates over an assessment period of one million years in a radioactive waste repository. (Author)

14 CFR 26.33 - Holders of type certificates: Fuel tank flammability.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Holders of type certificates: Fuel tank... Tank Flammability § 26.33 Holders of type certificates: Fuel tank flammability. (a) Applicability. This... part 25 of this chapter. (2) Exception. This paragraph (b) does not apply to— (i) Fuel tanks for which...

The potential for gas fired generation in Atlantic Canada

International Nuclear Information System (INIS)

MacDonald, T.

2002-01-01

The objective of this presentation was to stimulate discussion regarding the potential for Maritimes based gas fired power generation. It was noted that although the subject is complex, simplified assumptions are presented. The topics of discussion include the move to restructure the electric power industry in Nova Scotia and New Brunswick, the interest in gas fired generation in Atlantic Canada, the expected increase in natural gas consumption, and the issue of whether there is sufficient supply and adequate infrastructure to support demand. Other topics of discussion included the impact of regulations on the industry, and the future outlook of natural gas supply as it relates to power generation. The efforts of the natural gas industry to meet US natural gas generating requirements were also discussed. 3 tabs., 8 figs

Test plan for measuring ventilation rates and combustible gas levels in TWRS active catch tanks

Energy Technology Data Exchange (ETDEWEB)

NGUYEN, D.M.

1999-05-20

The purpose of this test is to provide an initial screening of combustible gas concentrations in catch tanks that currently are operated by Tank Waste Remediation System (TWRS). The data will be used to determine whether or not additional data will be needed for closure of the flammable gas unreviewed safety question for these facilities. This test will involve field measurements of ammonia, organic vapor, and total combustible gas levels in the headspace of the catch tanks. If combustible gas level in a tank exceeds an established threshold, gas samples will be collected in SUMMA canisters for more extensive laboratory analysis. In addition, ventilation rates of some catch tanks will be measured to evaluate removal of flammable gas by air flow through the tanks.

Test plan for measuring ventilation rates and combustible gas levels in RPP active catch tanks

Energy Technology Data Exchange (ETDEWEB)

NGUYEN, D.M.

1999-06-03

The purpose of this test is to provide an initial screening of combustible gas concentrations in catch tanks that currently are operated by River Protection Project (RPP). The data will be used to determine whether or not additional data will be needed for closure of the flammable gas unreviewed safety question for these facilities. This test will involve field measurements of ammonia, organic vapor, and total combustible gas levels in the headspace of the catch tanks. If combustible gas level in a tank exceeds an established threshold, gas samples will be collected in SUMMA canisters for more extensive laboratory analysis. In addition, ventilation rates of some catch tanks will be measured to evaluate removal of flammable gas by air flow through the tanks.

Clothing Flammability and Burn Injuries: Public Opinion Concerning an Overlooked, Preventable Public Health Problem.

Science.gov (United States)

Frattaroli, Shannon; Spivak, Steven M; Pollack, Keshia M; Gielen, Andrea C; Salomon, Michele; Damant, Gordon H

2016-01-01

The objective of this study was to describe knowledge of clothing flammability risk, public support for clothing flammability warning labels, and stronger regulation to reduce the risk. As part of a national survey of homeowners about residential sprinkler systems, the authors included questions about clothing flammability. The authors used an online web panel to sample homeowners and descriptive methods to analyze the resulting data. The sample included 2333 homeowners. Knowledge of clothing flammability and government oversight of clothing flammability risk was low. Homeowners were evenly split about the effectiveness of current standards; however, when presented with clothing-related burn injury and death data, a majority (53%) supported stricter standards. Most homeowners (64%) supported warning labels and indicated that such labels would either have no effect on their purchasing decisions (64%) or be an incentive (24%) to purchase an item. Owners of sprinkler-equipped homes were more likely to support these interventions than owners of homes without sprinkler systems. Public knowledge about clothing flammability risks is low. Most homeowners supported clothing labels to inform consumers of this risk and increased government intervention to reduce the risk.

ELECTRICITY GENERATION FROM LANDFILL GAS IN TURKEY.

Science.gov (United States)

Salihoglu, Nezih Kamil

2018-05-08

Landfill gas (LFG)-to-energy plants in Turkey were investigated, and the LFG-to-energy plant of a metropolitan municipal landfill was monitored for 3 years. Installed capacities and actual gas engine working hours were determined. An equation was developed to estimate the power capacity for LFG-to-energy plants for a given amount of landfilled waste. Monitoring the actual gas generation rates enabled determination of LFG generation factors for Turkish municipal waste. A significant relationship (R = 0.524, p kitchen waste generation behaviors influenced by the ambient temperature. However, no significant correlation was found between the ambient temperature and the generated LFG. A temperature buffering capacity was inferred to exist within the landfill, which enables the anaerobic reactions to continue functioning even during cold seasons. The average LFG and energy generation rates were 45 m 3 LFG/ton waste landfilled and 0.08 MWh/ton waste landfilled, respectively. The mean specific LFG consumption for electricity generation was 529 ± 28 m 3 /MWh.

46 CFR 105.10-15 - Flammable liquid.

Science.gov (United States)

2010-10-01

... FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-15 Flammable... vapor pressure of 14 pounds or more. 1 American Society of Testing Materials Standard D 323...

arXiv R&D studies on eco-friendly gas mixtures for the ALICE Muon Identifier

CERN Document Server

INSPIRE-00584065

Resistive Plate Chambers (RPCs), used for the Muon Spectrometer of the ALICE experiment at CERN LHC, are currently operated in maxi-avalanche mode with a low threshold value and without amplification in the front-end electronics. RPC detectors have shown a good operation stability with the current gas mixture during the entire Run 1 (2010$-$2013) and the ongoing Run 2 (2015$-$2018) at the LHC. The gas mixture is made up of $C_{2}H_{2}F_{4}$, $SF_{6}$ and $iC_{4}H_{10}$. Since the first two gases have high Global Warming Potentials (GWPs), there is the risk that they will be phased out of production in the next years, due to the recent restrictions and regulations of the European Union. Therefore, finding a new eco-friendly gas mixture has become extremely important in order to reduce the emissions of greenhouse gases. In addition, the present $iC_{4}H_{10}$ contribution makes the current gas mixture flammable. Non-flammable components, or at least in non-flammable concentrations, would be advisable to make th...

16 CFR 1611.3 - Flammability-general requirement.

Science.gov (United States)

2010-01-01

... STANDARD FOR THE FLAMMABILITY OF VINYL PLASTIC FILM The Standard § 1611.3 Flammability—general requirement. The rate of burning shall not exceed 1.2 in./sec as judged by the average of five determinations...

Process gas generator feeding internal combustion piston engines

Energy Technology Data Exchange (ETDEWEB)

Iwantscheff, G; Kostka, H; Henkel, H J

1978-10-26

The invention relates to a process gas generator feeding gaseous fuel to internal combustion piston engines. The cylinder linings of the internal combustion engine are enclosed by the catalytic reaction chamber of the process gas generator which contains perforated sintered nozzle bricks as carriers of the catalysts needed for the conversion. The reaction chamber is surrounded by the exhaust gas chamber around which a tube coil is ound which feeds the fuel charge to the reaction chamber after evaporation and mixing with exhaust gas and air. The fuel which may be used for this purpose, e.g., is low-octane gasoline or diesel fuel. In the reaction chamber the fuel is catalytically converted at temperatures above 200/sup 0/C, e.g., into low-molecular paraffins, carbon monoxide and hydrogen. Operation of the internal combustion engine with a process gas generator greatly reduces the pollutant content of the exhaust gases.

Radiolytic gas generation in plutonium contaminated waste materials

International Nuclear Information System (INIS)

Kazanjian, A.R.

1976-01-01

Many plutonium contaminated waste materials decompose into gaseous products because of exposure to alpha radiation. The gases generated (usually hydrogen) over long-storage periods may create hazardous conditions. To determine the extent of such hazards, knowing the gas generation yields is necessary. These yields were measured by contacting some common Rocky Flats Plant waste materials with plutonium and monitoring the enclosed atmospheres for extensive periods of time. The materials were Plexiglas, polyvinyl chloride, glove-box gloves, machining oil, carbon tetrachloride, chlorothene VG solvent, Kimwipes (dry and wet), polyethylene, Dowex-1 resin, and surgeon's gloves. Both 239 Pu oxide and 238 Pu oxide were used as radiation sources. The gas analyses were made by mass spectrometry and the results obtained were the total gas generation, the hydrogen generation, the oxygen consumption rate, and the gas composition over the entire storage period. Hydrogen was the major gas produced in most of the materials. The total gas yields varied from 0.71 to 16 cm 3 (standard temperature pressure) per day per curie of plutonium. The oxygen consumption rates varied from 0.0088 to 0.070 millimoles per day per gram of plutonium oxide-239 and from 0.0014 to 0.0051 millimoles per day per milligram 238 Pu

Origin of natural gas; Tennen gas no kigen

Energy Technology Data Exchange (ETDEWEB)

Katayama, Y. [The Institute of Applied Energy, Tokyo (Japan)

1996-03-20

Natural gas, which is a general term of flammable hydrocarbon gases such as methane, is classified by origin into the following categories : (1) oil field gas (oil gas), (2) aquifers (bacteria-fermented methane), (3) coal gas (coal field gas), and (4) abiogenetic gas. The natural gas which has (1-4) origins and is now used as resource in a large quantity is (1) oil field gas. This gas is a hydrocarbon gas recovered in the production process of petroleum and contains components such as ethane, propane and butane. To the contrary, (2) aquifers and (3) coal gas have methane as main component. As (4) abiogenetic methane, there are gas formed in inorganic reaction in activities of submarine volcanos and deep gas (earth origin gas). Oil field gas has kerogen origin. Aquifers were formed by fermentation of organic matters. Coal gas was formed by coalification of vitrinite. As abiogenetic methane, there are inorganic reaction formation gas and deep gas, the latter of which exists little as resource. 7 refs., 11 figs., 1 tab.

46 CFR 154.908 - Inert gas generator: Location.

Science.gov (United States)

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Inert gas generator: Location. 154.908 Section 154.908 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Atmospheric Control in Cargo Containment Systems § 154.908 Inert gas generator: Location. (a) Except as...

BFR Electrolyte Additive Safety and Flammability Characterization

Energy Technology Data Exchange (ETDEWEB)

Allcorn, Eric [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-10-13

Lithium-ion battery safety is a critical issue in the adoption of the chemistry to larger scale applications such as transportation and stationary storage. One of the critical components impacting the safety of lithium-ion batteries is their use of highly flammable organic electrolytes. In this work, brominated flame retardants (BFR’s) – an existing class of flame retardant materials – are incorporated as additives to lithium-ion battery electrolytes with the intention to reduce the electrolyte flammability and thereby improve safety. There are a few critical needs for a successful electrolyte additive: solubility in the electrolyte, electrochemical stability over the range of battery operation, and minimal detrimental effects on battery performance. Those detrimental effects can take the form of electrolyte specific impacts, such as a reduction in conductivity, or electrode impacts, such as SEI-layer modification or chemical instability to the active material. In addition to these needs, the electrolyte additive also needs to achieve its intended purpose, which in this case is to reduce the flammability of the electrolyte. For the work conducted as part of this SPP agreement three separate BFR materials were provided by Albemarle to be tested by Sandia as additives in a traditional lithium-ion battery electrolyte. The provided BFR materials were tribromo-neopentyl alcohol, tetrabromo bisphenol A, and tribromoethylene. These materials were incorporated as separate 4 wt.% additives into a traditional lithium-ion battery electrolyte and compared to said traditional electrolyte, designated Gen2.

46 CFR 182.480 - Flammable vapor detection systems.

Science.gov (United States)

2010-10-01

... 100 GROSS TONS) MACHINERY INSTALLATION Specific Machinery Requirements § 182.480 Flammable vapor... permit calibration in a vapor free atmosphere. (g) Electrical connections, wiring, and components for a...

Methods development for measuring and classifying flammability/combustibility of refrigerants. Interim report, task 2 - test plan

Energy Technology Data Exchange (ETDEWEB)

Heinonen, E.W.; Tapscott, R.E. [Univ. of New Mexico, Albuquerque, NM (United States)

1994-07-01

Regulations on alternative refrigerants and concerns for the environment are forcing the refrigeration industry to consider the use of potentially flammable fluids to replace CFC fluids currently in use. The objectives of this program are to establish the conditions under which refrigerants and refrigerant blends exhibit flammability and to develop appropriate methods to measure flammability.

Gas-Generator Augmented Expander Cycle Rocket Engine

Science.gov (United States)

Greene, William D. (Inventor)

2011-01-01

An augmented expander cycle rocket engine includes first and second turbopumps for respectively pumping fuel and oxidizer. A gas-generator receives a first portion of fuel output from the first turbopump and a first portion of oxidizer output from the second turbopump to ignite and discharge heated gas. A heat exchanger close-coupled to the gas-generator receives in a first conduit the discharged heated gas, and transfers heat to an adjacent second conduit carrying fuel exiting the cooling passages of a primary combustion chamber. Heat is transferred to the fuel passing through the cooling passages. The heated fuel enters the second conduit of the heat exchanger to absorb more heat from the first conduit, and then flows to drive a turbine of one or both of the turbopumps. The arrangement prevents the turbopumps exposure to combusted gas that could freeze in the turbomachinery and cause catastrophic failure upon attempted engine restart.

Estimation and Uncertainty Analysis of Flammability Properties of Chemicals using Group-Contribution Property Models

DEFF Research Database (Denmark)

Frutiger, Jerome; Abildskov, Jens; Sin, Gürkan

Process safety studies and assessments rely on accurate property data. Flammability data like the lower and upper flammability limit (LFL and UFL) play an important role in quantifying the risk of fire and explosion. If experimental values are not available for the safety analysis due to cost...... or time constraints, property prediction models like group contribution (GC) models can estimate flammability data. The estimation needs to be accurate, reliable and as less time consuming as possible. However, GC property prediction methods frequently lack rigorous uncertainty analysis. Hence....... In this study, the MG-GC-factors are estimated using a systematic data and model evaluation methodology in the following way: 1) Data. Experimental flammability data is used from AIChE DIPPR 801 Database. 2) Initialization and sequential parameter estimation. An approximation using linear algebra provides...

Gas-fired Power Generation in India: Challenges and opportunities

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

India's fast growing economy needs to add 100,000 MW power generating capacity between 2002-2012. Given limitations to the use of coal in terms of environmental considerations, quality and supply constraints, gas is expected to play an increasingly important role in India's power sector. This report briefs NMC Delegates on the potential for gas-fired power generation in India and describes the challenges India faces to translate the potential for gas-fired power generation into reality.

14 CFR Appendix N to Part 25 - Fuel Tank Flammability Exposure and Reliability Analysis

Science.gov (United States)

2010-01-01

..., Definitions). A non-flammable ullage is one where the fuel-air vapor is too lean or too rich to burn or is... Office for approval the fuel tank flammability analysis, including the airplane-specific parameters...

Review on flammability of biofibres and biocomposites

CSIR Research Space (South Africa)

Mngomezulu, ME

2013-10-01

Full Text Available The subject on flammability properties of natural fibre-reinforced biopolymer composites has not been broadly researched. This is not only evidenced by the minimal use of biopolymer composites and/or blends in different engineering areas where fire...

16 CFR 1145.3 - Extremely flammable contact adhesives; risk of burns from explosive vapor ignition and flashback...

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Extremely flammable contact adhesives; risk... TO OTHER ACTS UNDER THE CONSUMER PRODUCT SAFETY ACT § 1145.3 Extremely flammable contact adhesives... associated with certain extremely flammable contact adhesives under the Consumer Product Safety Act rather...

Species mixture effects on flammability across plant phylogeny: the importance of litter particle size and the special role for non-Pinus Pinaceae.

Science.gov (United States)

Zhao, Weiwei; Cornwell, William K; van Pomeren, Marinda; van Logtestijn, Richard S P; Cornelissen, Johannes H C

2016-11-01

Fire affects and is affected by plants. Vegetation varies in flammability, that is, its general ability to burn, at different levels of ecological organization. To scale from individual plant traits to community flammability states, understanding trait effects on species flammability variation and their interaction is important. Plant traits are the cumulative result of evolution and they show, to differing extents, phylogenetic conservatism. We asked whether phylogenetic distance between species predicts species mixture effects on litterbed flammability. We conducted controlled laboratory burns for 34 phylogenetically wide-ranging species and 34 random two-species mixtures from them. Generally, phylogenetic distance did not predict species mixture effects on flammability. Across the plant phylogeny, most species were flammable except those in the non- Pinus Pinaceae, which shed small needles producing dense, poorly ventilated litterbeds above the packing threshold and therefore nonflammable. Consistently, either positive or negative dominance effects on flammability of certain flammable or those non-flammable species were found in mixtures involving the non- Pinus Pinaceae. We demonstrate litter particle size is key to explaining species nonadditivity in fuelbed flammability. The potential of certain species to influence fire disproportionately to their abundance might increase the positive feedback effects of plant flammability on community flammability state if flammable species are favored by fire.

Textiles: Some technocal information and data III: Low flammable and other high performance fibres

CSIR Research Space (South Africa)

Hunter, L

1978-07-01

Full Text Available What it meant by the flammability of a texttile material? What exactly are the meaning of such term as "non-burning", "fire resistant", "self-extinquishing","non-combustible","flameproof",etc? Unfortunately the flammability properties to which...

Gas generation and migration analysis for TRU waste disposal system

International Nuclear Information System (INIS)

Ando, Kenichi; Noda, Masaru; Yamamoto, Mikihiko; Mihara, Morihiro

2005-09-01

In TRU waste disposal system, significant quantities of gases may be generated due to metal corrosion, radiolysis effect and microorganism activities. It is therefore recommended that the potential impact of gas generation and migration on TRU waste repository should be evaluated. In this study, gas generation rates were calculated in the repository and gas migration analysis in the disposal system were carried out using two phase flow model with results of gas generation rates. First, the time dependencies of gas generation rate in each TRU waste repositories were evaluated based on amounts of metal, organic matter and radioactivity. Next, the accumulation pressure of gases and expelled pore water volume nuclides in the repository were calculated by TOUGH2 code. After that, the results showed that the increase of gas pressure was the range of 1.3 to 1.4 MPa. In the repository with and without buffer, the rate of expelled pore water was 0.006 - 0.009 m 3 /y and 0.018 - 0.24m 3 /y, respectively. In addition, the radioactive gas migration through the repository and geosphere are evaluated. And re-saturation analysis is also performed to evaluate the initial condition of the system. (author)

High gas dependence for power generation in Thailand: The vulnerability analysis

International Nuclear Information System (INIS)

Nakawiro, Thanawat; Bhattacharyya, Subhes C.

2007-01-01

Thailand uses 74% of its natural gas supply for power generation and 70% of its power comes from gas-based technology. High dependence on natural gas in power generation raises concerns about security of electricity supply that could affect competitiveness of Thai manufacturing and other industries at the global level. The effect of fuel dependence on security of electricity supply has received less emphasis in the literature. Given this gap, this research examines the economic impact of high dependence on natural gas for power generation in Thailand by analyzing the effect of changes in fuel prices (including fuel oil and natural gas) on electricity tariff in Thailand. At the same time, the research quantifies the vulnerability of the Thai economy due to high gas dependence in power generation. Our research shows that for every 10% change in natural gas price, electricity tariff in Thailand would change by 3.5%. In addition, we found that the gas bill for power generation consumed between 1.94% and 3.05% of gross domestic product (GDP) between 2000 and 2004 and in terms of GDP share per unit of energy, gas dependence in power generation is almost similar to that of crude oil import dependence. We also found that the basic metal industry, being an electricity intensive industry, is the most affected industry. Additionally, we find that volatility of gas price is the main factor behind the vulnerability concern. The research accordingly simulates two mitigation options of the problem, namely reducing gas dependence and increasing efficiency of gas-fired power plants, where the results show that these methods can reduce the vulnerability of the country from high gas dependence in power generation

Heat Recovery From Tail Gas Incineration To Generate Power

Energy Technology Data Exchange (ETDEWEB)

Tawfik, Tarek

2010-09-15

Many industrial processes result in tail gas wastes that must be flared or incinerated to abide with environmental guidelines. Tail gas incineration occurs in several chemical processes resulting in high-temperature exhaust gas that simply go to the stack, thus wasting all that valuable heat! This paper discusses useful heat recovery and electric power generation utilizing available heat in exhaust gas from tail gas incinerators. This heat will be recovered in a waste-heat recovery boiler that will produce superheated steam to expand in a steam turbine to generate power. A detailed cost estimate is presented.

Using natural gas generation to improve power system efficiency in China

International Nuclear Information System (INIS)

Hu, Junfeng; Kwok, Gabe; Xuan, Wang; Williams, James H.; Kahrl, Fredrich

2013-01-01

China's electricity sector faces the challenge of managing cost increases, improving reliability, and reducing its environmental footprint even as operating conditions become more complex due to increasing renewable penetration, growing peak demand, and falling system load factors. Addressing these challenges will require changes in how power generation is planned, priced, and dispatched in China. This is especially true for natural gas generation, which is likely to play an important role in power systems worldwide as a flexible generation resource. Although natural gas is commonly perceived to be economically uncompetitive with coal in China, these perceptions are based on analysis that fails to account for the different roles that natural gas generation plays in power systems—baseload, load following, and peaking generation. Our analysis shows that natural gas generation is already cost-effective for meeting peak demand in China, resulting in improved capacity factors and heat rates for coal-fired generators and lower system costs. We find that the largest barrier to using natural gas for peaking generation in China is generation pricing, which could be addressed through modest reforms to support low capacity factor generation. - Highlights: • Using gas generation as a “capacity resource” in China could have multiple benefits. • Benefits include lower total costs, improved efficiency for coal generators. • Price reforms needed to support low capacity factor generation in China

Microgravity Flammability Experiments for Spacecraft Fire Safety

DEFF Research Database (Denmark)

Legros, Guillaume; Minster, Olivier; Tóth, Balazs

2012-01-01

As fire behaviour in manned spacecraft still remains poorly understood, an international topical team has been created to design a validation experiment that has an unprecedented large scale for a microgravity flammability experiment. While the validation experiment is being designed for a re-sup...

Obstacles to the penetration of electric generation markets by natural gas

International Nuclear Information System (INIS)

Schleede, G.R.

1992-01-01

This paper reviews and compares the advantages and disadvantages that electric power generators have in generating electricity from a variety of fuel sources. It then goes on to emphasize the use of natural gas and how it can become more competitive in the electric generation field. The paper is based primarily on experiences by the author during his employment with the New England Electric System (NEES). The author reviews the source of electricity for this utility and describes the percentages of each fuel source. It then goes on to specifically discuss the planned natural gas-fired projects in the utility system. The paper outlines the NEES strategy of diversification with respect to gas suppliers and describes the important considerations it used when planning for electric generation with gas. These include determining pressure requirements needed by the gas distribution system when the gas-generators come on-line; determining the placement of the generators within the overall system (i.e. peak load facilities, base load facilities, etc.); contracting flexibility because of the need to vary the amount of gas taken; and the ability to manage pipeline capacity and gas supplies when they are not needed

Outlook for gas sales for electricity generation in the Northeast

International Nuclear Information System (INIS)

Linderman, C.W.

1998-01-01

Issues regarding future supply and demand of natural gas as opposed to coal in the electric power generation sector, generation performance standards of coal plants, new combined cycle applications, distributed generation, and the advantages of natural gas over coal are discussed. The electricity demand and supply situation in the Northeast, present and future, and the growing movement toward green power, green power certification programs, the need and demand for disclosure of emissions and fuel source of supply, price and other customer information were summarized. Nuclear power generation and the chances of it being replaced by natural gas-fuelled generation are assessed. Some pipeline siting issues and the need for careful coordination with the electric system to minimize new corridors, are also reviewed. The advantages of natural gas in terms of technology and reduced pollution, hence cleaner air, were cited as the reasons why natural gas has almost unlimited potential as the fuel of choice well into the 21. century

Comparative funding consequences of large versus small gas-fired power generation units

International Nuclear Information System (INIS)

Johnson, N.G.

1995-01-01

Gas producers are increasingly looking to privately-owned gas-fired power generation as a major growth market to support the development of new fields being discovered across Australia. Gas-fired generating technology is more environmentally friendly than coal-fired power stations, has lower unit capital costs and has higher efficiency levels. With the recent downward trends in gas prices for power generation (especially in Western Australia) it is likely that gas will indeed be the consistently preferred fuel for generation in Australia. Gas producers should be sensitive to the different financial and risk characteristics of the potential market represented by large versus small gas-fired private power stations. These differences are exaggerated by the much sharper focus given by the private sector to quantify risk and to its allocation to the parties best able to manage it. The significant commercial differences between classes of generation projects result in gas producers themselves being exposed to diverging risk profiles through their gas supply contracts with generating companies. Selling gas to larger generation units results in gas suppliers accepting proportionately (i.e. not just prorata to the larger installed capacity) higher levels of financial risk. Risk arises from the higher probability of a project not being completed, from the increased size of penalty payments associated with non-delivery of gas and from the rising level of competition between gas suppliers. Gas producers must fully understand the economics and risks of their potential electricity customers and full financial analysis will materially help the gas supplier in subsequent commercial gas contract negotiations. (author). 1 photo

Accounting for fuel price risk when comparing renewable to gas-fired generation: the role of forward natural gas prices

International Nuclear Information System (INIS)

Bolinger, Mark; Wiser, Ryan; Golove, William

2006-01-01

Unlike natural gas-fired generation, renewable generation (e.g., from wind, solar, and geothermal power) is largely immune to fuel price risk. If ratepayers are rational and value long-term price stability, then-contrary to common practice-any comparison of the levelized cost of renewable to gas-fired generation should be based on a hedged gas price input, rather than an uncertain gas price forecast. This paper compares natural gas prices that can be locked in through futures, swaps, and physical supply contracts to contemporaneous long-term forecasts of spot gas prices. We find that from 2000 to 2003, forward gas prices for terms of 2-10 years have been considerably higher than most contemporaneous long-term gas price forecasts. This difference is striking, and implies that comparisons between renewable and gas-fired generation based on these forecasts over this period have arguably yielded results that are biased in favor of gas-fired generation

29 CFR 1910.253 - Oxygen-fuel gas welding and cutting.

Science.gov (United States)

2010-07-01

... 29 Labor 5 2010-07-01 2010-07-01 false Oxygen-fuel gas welding and cutting. 1910.253 Section 1910..., DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Welding, Cutting and Brazing § 1910.253 Oxygen-fuel gas welding and cutting. (a) General requirements—(1) Flammable mixture. Mixtures of fuel gases...

30 CFR 77.1103 - Flammable liquids; storage.

Science.gov (United States)

2010-07-01

... storage tanks shall be mounted securely on firm foundations. Outlet piping shall be provided with flexible connections or other special fittings to prevent adverse effects from tank settling. (c) Fuel lines shall be... hazards. (d) Areas surrounding flammable-liquid storage tanks and electric substations and transformers...

The ring of fire: the relative importance of fuel packing versus intrinsic leaf flammability

NARCIS (Netherlands)

Grootemaat, S.; Wright, I.J.; Cornelissen, J.H.C.; Viegas, D.X.

2014-01-01

Two different experimental set-ups were used to disentangle the relative importance of intrinsic leaf traits versus fuel packing for the flammability in fuel beds. Dried leaves from 25 Australian perennial species were burnt in fuel bed rings under controlled conditions. The flammability parameters

Effect of Meltable Triazine-DOPO Additive on Rheological, Mechanical, and Flammability Properties of PA6

Directory of Open Access Journals (Sweden)

Irina Butnaru

2015-08-01

Full Text Available Through a straightforward approach, a new meltable, halogen-free, nitrogen-phosphorus-based flame retardant (FR, 6-(2-(4,6-diamino-1,3,5-triazin-2-ylethyl dibenzo[c,e][1,2]oxaphosphinine 6-oxide (DTE-DOPO was synthesized and incorporated in polyamide 6 (PA6. It was proved that a very low phosphorus content of 1.46 wt% for DTE-DOPO additive improved the flame retardancy of PA6, leading to a non-flammable material. The performance of the new additive was compared to that of the commercially-available Exolit® OP 1230. The PA6 formulations were evaluated by measuring the rheological, mechanical, and flammability behavior. Using compounding by melt extrusion, 17 wt% additives was introduced into PA6 matrix and the corresponding formulations were characterized. The results evidenced a higher homogeneity of DTE-DOPO with PA6, a high thermal stability with a catalyzing decomposition effect on PA6 caused by the presence of the new developed FR, enhanced elasticity for the PA6/DTE-DOPO formulation and a V0 rating for both formulations. Thermal and fire analysis indicated a primary gas-phase activity, combined with a complete suppression of the self-sustained burning for the PA6/DTE-DOPO formulation.

DOE/DOE Tight Oil Flammability & Transportation Spill Safety

Energy Technology Data Exchange (ETDEWEB)

Lord, David L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-12-01

This presentation describes crude oils, their phase behavior, the SPR vapor pressure program, and presents data comparisons from various analytical techniques. The overall objective is to describe physical properties of crude oil relevant to flammability and transport safety

Lifecycle greenhouse gas emissions of coal, conventional and unconventional natural gas for electricity generation

Science.gov (United States)

An analysis of the lifecycle greenhouse gas (GHG) emissions associated with natural gas use recently published by Howarth et al. (2011) stated that use of natural gas produced from shale formations via hydraulic fracturing would generate greater lifecycle GHG emissions than petro...

Gas Generation from K East Basin Sludges - Series II Testing

International Nuclear Information System (INIS)

Bryan, Samuel A.; Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R.; Thornton, Brenda M.

2001-01-01

This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor, pit and canister sludge. Mixed and unmixed and fractionated KE canister sludge were tested, along with floor and pit sludges from areas in the KE Basin not previously sampled. The first report in this series focused on gas generation from KE floor and canister sludge collected using a consolidated sampling technique. The third report will present results of gas generation testing of irradiated uranium fuel fragments with and without sludge addition. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge

Fires in the Cenozoic: a late flowering of flammable ecosystems

Directory of Open Access Journals (Sweden)

William John Bond

2015-01-01

Full Text Available Modern flammable ecosystems include tropical and subtropical savannas, steppe grasslands, boreal forests and temperate sclerophyll shrublands. Despite the apparent fiery nature of much contemporary vegetation, terrestrial fossil evidence would suggest we live in a time of low fire activity relative to the deep past. The inertinite content of coal, fossil charcoal, is strikingly low from the Eocene to the Pleistocene and no charcoalified mesofossils have been reported for the Cenozoic. Marine cores have been analysed for charcoal in the North Pacific, the north and south Atlantic off Africa, and the south China sea. These tell a different story with the oldest records indicating low levels of fire activity from the Eocene but a surge of fire from the late Miocene (~7 Ma. Phylogenetic studies of woody plants adapted to frequent savanna fires show them beginning to appear from the Late Miocene with peak origins in the late Pliocene in both South American and African lineages. Phylogenetic studies indicate ancient origins (60 Ma+ for clades characteristic of flammable sclerophyll vegetation from Australia and the Cape region of South Africa. However, as for savannas, there was a surge of speciation from the Late Miocene associated with the retreat of closed fire-intolerant forests. The wide geographic spread of increased fire activity in the last few million years suggests a global cause. However none of the potential global factors (oxygen, rainfall seasonality, CO2 , novel flammable growth forms provides an adequate explanation as yet. The global patterns and processes of fire and flammable vegetation in the Cenozoic, especially since the Late Miocene, deserve much more attention to better understand fire in the earth system.

Fires in the Cenozoic: a late flowering of flammable ecosystems.

Science.gov (United States)

Bond, William J

2014-01-01

Modern flammable ecosystems include tropical and subtropical savannas, steppe grasslands, boreal forests, and temperate sclerophyll shrublands. Despite the apparent fiery nature of much contemporary vegetation, terrestrial fossil evidence would suggest we live in a time of low fire activity relative to the deep past. The inertinite content of coal, fossil charcoal, is strikingly low from the Eocene to the Pleistocene and no charcoalified mesofossils have been reported for the Cenozoic. Marine cores have been analyzed for charcoal in the North Pacific, the north and south Atlantic off Africa, and the south China sea. These tell a different story with the oldest records indicating low levels of fire activity from the Eocene but a surge of fire from the late Miocene (~7 Ma). Phylogenetic studies of woody plants adapted to frequent savanna fires show them beginning to appear from the Late Miocene with peak origins in the late Pliocene in both South American and African lineages. Phylogenetic studies indicate ancient origins (60 Ma+) for clades characteristic of flammable sclerophyll vegetation from Australia and the Cape region of South Africa. However, as for savannas, there was a surge of speciation from the Late Miocene associated with the retreat of closed fire-intolerant forests. The wide geographic spread of increased fire activity in the last few million years suggests a global cause. However, none of the potential global factors (oxygen, rainfall seasonality, CO2, novel flammable growth forms) provides an adequate explanation as yet. The global patterns and processes of fire and flammable vegetation in the Cenozoic, especially since the Late Miocene, deserve much more attention to better understand fire in the earth system.

Accounting for fuel price risk: Using forward natural gas prices instead of gas price forecasts to compare renewable to natural gas-fired generation

Energy Technology Data Exchange (ETDEWEB)

Bolinger, Mark; Wiser, Ryan; Golove, William

2003-08-13

Against the backdrop of increasingly volatile natural gas prices, renewable energy resources, which by their nature are immune to natural gas fuel price risk, provide a real economic benefit. Unlike many contracts for natural gas-fired generation, renewable generation is typically sold under fixed-price contracts. Assuming that electricity consumers value long-term price stability, a utility or other retail electricity supplier that is looking to expand its resource portfolio (or a policymaker interested in evaluating different resource options) should therefore compare the cost of fixed-price renewable generation to the hedged or guaranteed cost of new natural gas-fired generation, rather than to projected costs based on uncertain gas price forecasts. To do otherwise would be to compare apples to oranges: by their nature, renewable resources carry no natural gas fuel price risk, and if the market values that attribute, then the most appropriate comparison is to the hedged cost of natural gas-fired generation. Nonetheless, utilities and others often compare the costs of renewable to gas-fired generation using as their fuel price input long-term gas price forecasts that are inherently uncertain, rather than long-term natural gas forward prices that can actually be locked in. This practice raises the critical question of how these two price streams compare. If they are similar, then one might conclude that forecast-based modeling and planning exercises are in fact approximating an apples-to-apples comparison, and no further consideration is necessary. If, however, natural gas forward prices systematically differ from price forecasts, then the use of such forecasts in planning and modeling exercises will yield results that are biased in favor of either renewable (if forwards < forecasts) or natural gas-fired generation (if forwards > forecasts). In this report we compare the cost of hedging natural gas price risk through traditional gas-based hedging instruments (e

Miniature Gas-Turbine Power Generator

Science.gov (United States)

Wiberg, Dean; Vargo, Stephen; White, Victor; Shcheglov, Kirill

2003-01-01

A proposed microelectromechanical system (MEMS) containing a closed- Brayton-cycle turbine would serve as a prototype of electric-power generators for special applications in which high energy densities are required and in which, heretofore, batteries have been used. The system would have a volume of about 6 cm3 and would operate with a thermal efficiency >30 percent, generating up to 50 W of electrical power. The energy density of the proposed system would be about 10 times that of the best battery-based systems now available, and, as such, would be comparable to that of a fuel cell. The working gas for the turbine would be Xe containing small quantities of CO2, O2, and H2O as gaseous lubricants. The gas would be contained in an enclosed circulation system, within which the pressure would typically range between 5 and 50 atm (between 0.5 and 5 MPa). The heat for the Brayton cycle could be supplied by any of a number of sources, including a solar concentrator or a combustor burning a hydrocarbon or other fuel. The system would include novel heat-transfer and heat-management components. The turbine would be connected to an electric power generator/starter motor. The system would include a main rotor shaft with gas bearings; the bearing surfaces would be made of a ceramic material coated with nanocrystalline diamond. The shaft could withstand speed of 400,000 rpm or perhaps more, with bearing-wear rates less than 10(exp -)4 those of silicon bearings and 0.05 to 0.1 those of SiC bearings, and with a coefficient of friction about 0.1 that of Si or SiC bearings. The components of the system would be fabricated by a combination of (1) three-dimensional xray lithography and (2) highly precise injection molding of diamond-compatible metals and ceramic materials. The materials and fabrication techniques would be suitable for mass production. The disadvantages of the proposed system are that unlike a battery-based system, it could generate a perceptible amount of sound, and

The greenhouse impact of unconventional gas for electricity generation

Energy Technology Data Exchange (ETDEWEB)

Hultman, Nathan; Ramig, Christopher [School of Public Policy, University of Maryland, 2101 Van Munching Hall, College Park, MD 20742 (United States); Rebois, Dylan [Department of Mechanical Engineering, University of Maryland, 2181 Glenn L Martin Hall, Building 088, College Park, MD 20742 (United States); Scholten, Michael [Joint Quantum Institute, University of Maryland, 2207 Computer and Space Sciences Building, College Park, MD 20742 (United States)

2011-10-15

New techniques to extract natural gas from unconventional resources have become economically competitive over the past several years, leading to a rapid and largely unanticipated expansion in natural gas production. The US Energy Information Administration projects that unconventional gas will supply nearly half of US gas production by 2035. In addition, by significantly expanding and diversifying the gas supply internationally, the exploitation of new unconventional gas resources has the potential to reshape energy policy at national and international levels-altering geopolitics and energy security, recasting the economics of energy technology investment decisions, and shifting trends in greenhouse gas (GHG) emissions. In anticipation of this expansion, one of the perceived core advantages of unconventional gas-its relatively moderate GHG impact compared to coal-has recently come under scrutiny. In this paper, we compare the GHG footprints of conventional natural gas, unconventional natural gas (i.e. shale gas that has been produced using the process of hydraulic fracturing, or 'fracking'), and coal in a transparent and consistent way, focusing primarily on the electricity generation sector. We show that for electricity generation the GHG impacts of shale gas are 11% higher than those of conventional gas, and only 56% that of coal for standard assumptions.

Gas temperature of capacitance spark discharge in air

International Nuclear Information System (INIS)

Ono, Ryo; Nifuku, Masaharu; Fujiwara, Shuzo; Horiguchi, Sadashige; Oda, Tetsuji

2005-01-01

Capacitance spark discharge has been widely used for studying the ignition of flammable gas caused by electrostatic discharge. In the present study, the gas temperature of capacitance spark discharge is measured. The gas temperature is an important factor in understanding the electrostatic ignition process because it influences the reaction rate of ignition. Spark discharge is generated in air with a pulse duration shorter than 100 ns. The discharge energy is set to 0.03-1 mJ. The rotational and vibrational temperatures of the N 2 molecule are measured using the emission spectrum of the N 2 second positive system. The rotational and vibrational temperatures are estimated to be 500 and 5000 K, respectively, which are independent of the discharge energy. This result indicates that most of the electron energy is consumed in the excitation of vibrational levels of molecules rather than the heating of the gas. The gas temperature after discharge is also measured by laser-induced fluorescence of OH radicals. It is shown that the gas temperature increases after discharge and reaches approximately 1000 K at 3 μs after discharge. Then the temperature decreases at a rate in the range of 8-35 K/μs depending on the discharge energy

Characterization and calibration of gas sensor systems at ppb level—a versatile test gas generation system

Science.gov (United States)

Leidinger, Martin; Schultealbert, Caroline; Neu, Julian; Schütze, Andreas; Sauerwald, Tilman

2018-01-01

This article presents a test gas generation system designed to generate ppb level gas concentrations from gas cylinders. The focus is on permanent gases and volatile organic compounds (VOCs) for applications like indoor and outdoor air quality monitoring or breath analysis. In the design and the setup of the system, several issues regarding handling of trace gas concentrations have been considered, addressed and tested. This concerns not only the active fluidic components (flow controllers, valves), which have been chosen specifically for the task, but also the design of the fluidic tubing regarding dead volumes and delay times, which have been simulated for the chosen setup. Different tubing materials have been tested for their adsorption/desorption characteristics regarding naphthalene, a highly relevant gas for indoor air quality monitoring, which has generated high gas exchange times in a previous gas mixing system due to long time adsorption/desorption effects. Residual gas contaminations of the system and the selected carrier air supply have been detected and quantified using both an analytical method (GC-MS analysis according to ISO 16000-6) and a metal oxide semiconductor gas sensor, which detected a maximum contamination equivalent to 28 ppb of carbon monoxide. A measurement strategy for suppressing even this contamination has been devised, which allows the system to be used for gas sensor and gas sensor system characterization and calibration in the low ppb concentration range.

High pressure gas driven liquid metal MHD homopolar generator

International Nuclear Information System (INIS)

Itoh, Yasuyuki

1988-01-01

A liquid metal MHD homopolar generator is proposed to be used as a high repetition rate pulsed power supply. In the generator, the thermal energy stored in a high pressure gas (He) reservoir is rapidly converted into kinetic energy of a rotating liquid metal (NaK) cylinder which is contracted by a gas driven annular free piston. The rotational kinetic energy is converted into electrical energy by making use of the homopolar generator principle. The conversion efficiency is calculated to be 47% in generating electrical energy of 20 kJ/pulse (1.7 MW peak power) at a repetition rate of 7 Hz. From the viewpoint of energy storage, the high pressure gas reservoir with a charging pressure of 15 MPa is considered to ''electrically'' store the energy at a density of 10 MJ/m 3 . (author)

The greenhouse impact of unconventional gas for electricity generation

International Nuclear Information System (INIS)

Hultman, Nathan; Ramig, Christopher; Rebois, Dylan; Scholten, Michael

2011-01-01

New techniques to extract natural gas from unconventional resources have become economically competitive over the past several years, leading to a rapid and largely unanticipated expansion in natural gas production. The US Energy Information Administration projects that unconventional gas will supply nearly half of US gas production by 2035. In addition, by significantly expanding and diversifying the gas supply internationally, the exploitation of new unconventional gas resources has the potential to reshape energy policy at national and international levels—altering geopolitics and energy security, recasting the economics of energy technology investment decisions, and shifting trends in greenhouse gas (GHG) emissions. In anticipation of this expansion, one of the perceived core advantages of unconventional gas—its relatively moderate GHG impact compared to coal—has recently come under scrutiny. In this paper, we compare the GHG footprints of conventional natural gas, unconventional natural gas (i.e. shale gas that has been produced using the process of hydraulic fracturing, or 'fracking'), and coal in a transparent and consistent way, focusing primarily on the electricity generation sector. We show that for electricity generation the GHG impacts of shale gas are 11% higher than those of conventional gas, and only 56% that of coal for standard assumptions.

Outlier treatment for improving parameter estimation of group contribution based models for upper flammability limit

DEFF Research Database (Denmark)

Frutiger, Jerome; Abildskov, Jens; Sin, Gürkan

2015-01-01

Flammability data is needed to assess the risk of fire and explosions. This study presents a new group contribution (GC) model to predict the upper flammability limit UFL oforganic chemicals. Furthermore, it provides a systematic method for outlier treatment inorder to improve the parameter...

The TRUPACT-II Matrix Depleton Program

International Nuclear Information System (INIS)

Connolly, M.J.; Djordjevic, S.M.; Loehr, C.A.; Smith, M.C.; Banjac, V.; Lyon, W.F.

1995-01-01

Contact-handled transuranic (CH-TRU) wastes will be shipped and disposed at the Waste Isolation Pilot Plant (WIPP) repository in the Transuranic Package Transporter-II (TRUPACT-II) shipping package. A primary transportation requirement for the TRUPACT-II is that the concentration of potentially flammable gases (i.e., hydrogen and methane) must not exceed 5 percent by volume in the package or the payload during a 60-day shipping period. Decomposition of waste materials by radiation, or radiolysis, is the predominant mechanism of gas generation during transport. The gas generation potential of a target waste material is characterized by a G-value, which is the number of molecules of gas generated per 100 eV of ionizing radiation absorbed by the target material. To demonstrate compliance with the flammable gas concentration requirement, theoretical worst-case calculations were performed to establish allowable wattage (decay heat) limits for waste containers. The calculations were based on the G-value for the waste material with the highest potential for flammable gas generation. The calculations also made no allowances for decreases of the G-value over time due to matrix depletion phenomena that have been observed by many experimenters. Matrix depletion occurs over time when an alpha-generating source particle alters the target material (by evaporation, reaction, or decomposition) into a material of lower gas generating potential. The net effect of these alterations is represented by the ''effective G-value.''

Effect of melamine phosphate on the thermal stability and flammability of bio-based polyurethanes

International Nuclear Information System (INIS)

Yakushin, Vladimir; Sevastyanova, Irina; Vilsone, Dzintra; Avots, Andris

2016-01-01

The effect of melamine phosphate (MP) on the thermal stability of bio-based polyurethane and the flammability parameters of wood samples with polyurethane coatings was studied. Thermogravimetric analysis and cone calorimeter test at a heat flux of 35 kW/m 2 were used for this purpose. The main characteristics of the thermal stability and flammability of the coating with addition of MP were compared with the characteristics of analogous coatings with addition of ammonium polyphosphate (APP), as well as APP in combination with melamine. It was found that the use of MP as an intumescent additive allows a considerable decrease of most of the flammability parameters of the polyurethane based on tall oil fatty acids, like APP. To reach the maximum effect, it is enough to load in the polyurethane 20% of MP. In contrast to APP, MP reduces also the smoke release of the samples. Using MP in combination with APP at definite weight ratios, it is possible to essentially reduce the flammability parameters of polyurethane coatings, such as PHRR, THR and MARHE. (paper)

Condensation heat transfer coefficients of flammable refrigerants on various enhanced tubes

International Nuclear Information System (INIS)

Park, Ki Jung; Jung, Dong Soo

2005-01-01

In this study, external condensation Heat Transfer Coefficients (HTCs) of six flammable refrigerants of propylene (R1270), propane (R290), isobutane (R600a), butane (R600), dimethylether (RE170), and HFC32 were measured at the vapor temperature of 39 .deg. C on a 1023 fpm low fin and turbo-C tubes. All data were taken under the heat flux of 32∼116 and 42∼142 kW/m 2 for the low fin and turbo-C tubes respectively. Flammable refrigerants' data obtained on enhanced tubes showed a typical trend that external condensation HTCs decrease with increasing wall subcooling. HFC32 and DME showed up to 30% higher HTCs than those of HCFC22 due to their excellent thermophysical properties. Propylene, propane, isobutane, and butane showed similar or lower HTCs than those of HCFC22. Beatty and Katz' correlation predicted the HTCs of the flammable refrigerants obtained on a low fin tube within a mean deviation of 7.3%. Turbo-C tube showed the best performance due to its 3 dimensional surface geometry for fast removal of condensate

Country-Level Life Cycle Assessment of Greenhouse Gas Emissions from Liquefied Natural Gas Trade for Electricity Generation.

Science.gov (United States)

Kasumu, Adebola S; Li, Vivian; Coleman, James W; Liendo, Jeanne; Jordaan, Sarah M

2018-02-20

In the determination of the net impact of liquefied natural gas (LNG) on greenhouse gas emissions, life cycle assessments (LCA) of electricity generation have yet to combine the effects of transport distances between exporting and importing countries, country-level infrastructure in importing countries, and the fuel sources displaced in importing countries. To address this, we conduct a LCA of electricity generated from LNG export from British Columbia, Canada with a three-step approach: (1) a review of viable electricity generation markets for LNG, (2) the development of results for greenhouse gas emissions that account for transport to importing nations as well as the infrastructure required for power generation and delivery, and (3) emissions displacement scenarios to test assumptions about what electricity is being displaced in the importing nation. Results show that while the ultimate magnitude of the greenhouse gas emissions associated with natural gas production systems is still unknown, life cycle greenhouse gas emissions depend on country-level infrastructure (specifically, the efficiency of the generation fleet, transmission and distribution losses and LNG ocean transport distances) as well as the assumptions on what is displaced in the domestic electricity generation mix. Exogenous events such as the Fukushima nuclear disaster have unanticipated effects on the emissions displacement results. We highlight national regulations, environmental policies, and multilateral agreements that could play a role in mitigating emissions.

LIQUIFIED NATURAL GAS (LNG) CARRIERS

OpenAIRE

Daniel Posavec; Katarina Simon; Matija Malnar

2010-01-01

Modern liquefied natural gas carriers are double-bottom ships classified according to the type of LNG tank. The tanks are specially designed to store natural gas cooled to -161°C, the boiling point of methane. Since LNG is highly flammable, special care must be taken when designing and operating the ship. The development of LNG carriers has begun in the middle of the twentieth century. LNG carrier storage space has gradually grown to the current maximum of 260000 m3. There are more than 300 L...

Generator gas as a fuel to power a diesel engine

Directory of Open Access Journals (Sweden)

Tutak Wojciech

2014-01-01

Full Text Available The results of gasification process of dried sewage sludge and use of generator gas as a fuel for dual fuel turbocharged compression ignition engine are presented. The results of gasifying showed that during gasification of sewage sludge is possible to obtain generator gas of a calorific value in the range of 2.15  2.59 MJ/m3. It turned out that the generator gas can be effectively used as a fuel to the compression ignition engine. Because of gas composition, it was possible to run engine with partload conditions. In dual fuel operation the high value of indicated efficiency was achieved equal to 35%, so better than the efficiency of 30% attainable when being fed with 100% liquid fuel. The dual fuel engine version developed within the project can be recommended to be used in practice in a dried sewage sludge gasification plant as a dual fuel engine driving the electric generator loaded with the active electric power limited to 40 kW (which accounts for approx. 50% of its rated power, because it is at this power that the optimal conditions of operation of an engine dual fuel powered by liquid fuel and generator gas are achieved. An additional advantage is the utilization of waste generated in the wastewater treatment plant.

Prediction methods for the calculation of the flammability properties of gases and vapors: CHETAH and ASTM software. Part 1. Esters and Ethers

International Nuclear Information System (INIS)

Gigante, L.; Dellavedova, M.; Pasturenzi, C.; Lunghi, A.; Cardillo, P.

2008-01-01

After the law by decree of the 12. June 2003, N 233 (ATEX Directive) and REACH regulation (Regulation EC n. 2907/2006 of the European Parliament), several industrial fields, also not chemical, need the flammability data for the substances used. Perhaps, many of these data, especially for compounds with not common uses, are not easy to collect. It would be helpful to provide prediction methods in order to calculate these data without any experimentation that sometimes results time consuming, expensive and practically impossible for all the commercial compounds. In this research the ASTM software CHETAH (CHEmical Thermodynamic And Hazard evaluation) has been used in order to compute the lower flammability limit (L i ), the limiting oxygen concentration (LOC, using nitrogen as inert gas) as a function of temperature, the adiabatic flame temperature T flame , the fundamental burning velocity (S u ), the quenching distance (Q d ), the minimum ignition energy (MIE) for esters and ethers, substances highly used in industry. [it

A flammability and combustion model for integrated accident analysis

International Nuclear Information System (INIS)

Plys, M.G.; Astleford, R.D.; Epstein, M.

1988-01-01

A model for flammability characteristics and combustion of hydrogen and carbon monoxide mixtures is presented for application to severe accident analysis of Advanced Light Water Reactors (ALWR's). Flammability of general mixtures for thermodynamic conditions anticipated during a severe accident is quantified with a new correlation technique applied to data for several fuel and inertant mixtures and using accepted methods for combining these data. Combustion behavior is quantified by a mechanistic model consisting of a continuity and momentum balance for the burned gases, and considering an uncertainty parameter to match the idealized process to experiment. Benchmarks against experiment demonstrate the validity of this approach for a single recommended value of the flame flux multiplier parameter. The models presented here are equally applicable to analysis of current LWR's. 21 refs., 16 figs., 6 tabs

Natural gas for power generation : issues and implications : an energy market assessment

International Nuclear Information System (INIS)

2006-06-01

This report presented a historical examination of trends in natural gas-fired generation as well as a perspective on the issues and potential implications of increasing reliance on natural gas. Potential changes to Canadian energy consumers were reviewed in addition to natural gas infrastructure and services. Electricity prices relating to natural gas generation were examined. A broad regional and continental perspective was employed to account for energy market integration and the fact that gas trends reflect developments outside of Canada. The report was divided into 2 sections: (1) an examination of the trend toward natural-gas fired generation of electricity in North America; and (2) an examination of issues in closer detail from a regional perspective followed by a discussion of the changes in generation and natural gas markets in western, eastern, and central North America. Questions arising from the analysis of specific regional supply, demand and infrastructure situations were also examined. Recommendations were presented for issues concerning the current gas market and the appropriate role of the government in ensuring adequate generation. Uncertainties in future natural gas supply were also considered. It was concluded that rapid industrial growth will continue to increase demand for natural gas and electricity supply. 5 figs

16 CFR Figure 5 to Part 1610 - An Example of a Typical Gas Shield

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false An Example of a Typical Gas Shield 5 Figure 5 to Part 1610 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT... Example of a Typical Gas Shield ER25MR08.004 ...

Flow Effects on the Flammability Diagrams of Solid Fuels: Microgravity Influence on Ignition Delay

Science.gov (United States)

Cordova, J. L.; Walther, D. C.; Fernandez-Pello, A. C.; Steinhaus, T.; Torero, J. L.; Quintere, J. G.; Ross, H. D.

1999-01-01

The possibility of an accidental fire in space-based facilities is a primary concern of space exploration programs. Spacecraft environments generally present low velocity air currents produced by ventilation and heating systems (of the order of 0.1 m/s), and fluctuating oxygen concentrations around that of air due to CO2 removal systems. Recent experiments of flame spread in microgravity show the spread rate to be faster and the limiting oxygen concentration lower than in normal-gravity. To date, there is not a material flammability-testing protocol that specifically addresses issues related to microgravity conditions. The present project (FIST) aims to establish a testing methodology that is suitable for the specific conditions of reduced gravity. The concepts underlying the operation of the LIFT apparatus, ASTM-E 1321-93, have been used to develop the Forced-flow Ignition and flame-Spread Test (FIST). As in the LIFT, the FIST is used to obtain the flammability diagrams of the material, i.e., graphs of ignition delay time and flame spread rate as a function of the externally applied radiant flux, but under forced flow rather than natural convection conditions, and for different oxygen concentrations. Although the flammability diagrams are similar, the flammability properties obtained with the FIST are found to depend on the flow characteristics. A research program is currently underway with the purpose of implementing the FIST as a protocol to characterize the flammability performance of solid materials to be used in microgravity facilities. To this point, tests have been performed with the FIST apparatus in both normal-gravity and microgravity conditions to determine the effects of oxidizer flow characteristics on the flammability diagrams of polymethylmethacrylate (PMMA) fuel samples. The experiments are conducted at reduced gravity in a KC- 135 aircraft following a parabolic flight trajectory that provides up to 25 seconds of low gravity. The objective of the

Gas generation matrix depletion quality assurance project plan

International Nuclear Information System (INIS)

1998-01-01

The Los Alamos National Laboratory (LANL) is to provide the necessary expertise, experience, equipment and instrumentation, and management structure to: Conduct the matrix depletion experiments using simulated waste for quantifying matrix depletion effects; and Conduct experiments on 60 cylinders containing simulated TRU waste to determine the effects of matrix depletion on gas generation for transportation. All work for the Gas Generation Matrix Depletion (GGMD) experiment is performed according to the quality objectives established in the test plan and under this Quality Assurance Project Plan (QAPjP)

Natural gas for electric power generation: Strategic issues, risks and opportunities

International Nuclear Information System (INIS)

Linderman, C.

1992-01-01

Natural gas is again being regarded as a significant fuel for electric power generation. It was once a predominant fuel for utilities in gas-producing areas, but natural gas consumption declined greatly after the 1973 oil shock because of reduced electricity demand and increased coal and nuclear generation. Moreover, wellhead price and other forms of regulation produced gas shortages in the 1970s. The resurgence of natural gas in future resource plans stems from its inherent ideal fuel characteristics: short lead time; low capital costs; small increments of modular capacity; delivered close to load centers; environmentally benign, preferable to oil and coal; and potential for high thermal efficiency in gas turbines. Natural gas, if available and attractively priced, is an ideal fuel for electric power generation. No other fuel shares these attractive characteristics, and utilities, facing higher than expected load growth, are relying on an increasing proportion of gas-fired combustion turbines, combined cycle plants, and cogeneration to meet a growing, yet uncertain, future demand for electricity. Despite these desirable operating characteristics, the varied past and uncertain future of natural gas markets raise legitimate concerns about the riskiness of current utility natural gas strategies. This report, which summarizes the major findings from research efforts, is intended to help utility decision-makers understand the full range of risks they face with natural gas electric power generation and to identify actions they can take to mitigate those risks

Influence of Knits Structure on Flammability and Comfortability

Directory of Open Access Journals (Sweden)

Mikučionienė D.

2014-12-01

Full Text Available Investigations of the influence of the knit structure, i.e. the loop length and the number of yarns in a loop, on flammability and comfortability are presented in this paper. The investigations were carried out using single jersey knits from Delta TA 18 tex × 2 yarns with five variants of a loop length. Single yarn as well as folded yarn from two single yarns was used in the investigations. Comparison of the results of single-layer knits flammability and air permeability with those of multilayer packet was made. The results obtained show that an increase in the loop length of the knit increases their permeability to air and decreases the burning time as well as increase in the number of layers decreases the air permeability and increases the burning time. Moreover, the similar burning time with significantly different permeability to air can be achieved changing the basic knitting parameters, i.e. the loop length and/or the yarn linear density.

Development of biomass gasification systems for gas turbine power generation

International Nuclear Information System (INIS)

Larson, E.D.; Svenningsson, P.

1991-01-01

Gas turbines are of interest for biomass applications because, unlike steam turbines, they have relatively high efficiencies and low unit capital costs in the small sizes appropriate for biomass installations. Gasification is a simple and efficient way to make biomass usable in gas turbines. The authors evaluate here the technical requirements for gas turbine power generation with biomass gas and the status of pressurized biomass gasification and hot gas cleanup systems. They also discuss the economics of gasifier-gas turbine cycles and make some comparisons with competing technologies. Their analysis indicates that biomass gasifiers fueling advanced gas turbines are promising for cost-competitive cogeneration and central station power generation. Gasifier-gas turbine systems are not available commercially, but could probably be developed in 3 to 5 years. Extensive past work related to coal gasification and pressurized combustion of solid fuels for gas turbines would be relevant in this effort, as would work on pressurized biomass gasification for methanol synthesis

Reactive intermediates in the gas phase generation and monitoring

CERN Document Server

Setser, D W

2013-01-01

Reactive Intermediates in the Gas Phase: Generation and Monitoring covers methods for reactive intermediates in the gas phase. The book discusses the generation and measurement of atom and radical concentrations in flow systems; the high temperature flow tubes, generation and measurement of refractory species; and the electronically excited long-lived states of atoms and diatomic molecules in flow systems. The text also describes the production and detection of reactive species with lasers in static systems; the production of small positive ions in a mass spectrometer; and the discharge-excite

16 CFR 1500.46 - Method for determining flashpoint of extremely flammable contents of self-pressurized containers.

Science.gov (United States)

2010-01-01

... extremely flammable contents of self-pressurized containers. 1500.46 Section 1500.46 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS HAZARDOUS SUBSTANCES AND... extremely flammable contents of self-pressurized containers. Use the apparatus described in § 1500.43a. Use...

Natural gas poised to penetrate deeper into electric generation

International Nuclear Information System (INIS)

Swanekamp, R.

1995-01-01

This article describes how advancements in gas supply, distribution and storage, coupled with new options in combustion equipment, continue to expand the use of natural gas for electric generation. The challenge is to meet the increasing demand while keeping prices competitive with other fuels--and keep a small band of skeptics at bay. To prepare for the projected growth in gas consumption, the natural-gas industry has invented in new infrastructure and technologies. Pipelines have been built; storage facilities have been expanded; and highly precise flow measurement stations have been installed. To mitigate supply and price risk, suppliers are offering short-, mid-, or long-term contracts which include service options and guarantees. In spite of these preparations, not all power producers are comfortable with the potential tidal wave of gas-fired capacity. Reason: It limits the electric-generation resource base to one fuel for future capacity

Power-generation method using combined gas and steam turbines

Energy Technology Data Exchange (ETDEWEB)

Liu, C; Radtke, K; Keller, H J

1997-03-20

The invention concerns a method of power generation using a so-called COGAS (combined gas and steam) turbine installation, the aim being to improve the method with regard to the initial costs and energy consumption so that power can be generated as cheaply as possible. This is achieved by virtue of the fact that air taken from the surrounding atmosphere is splint into an essentially oxygen-containing stream and an essentially nitrogen-containing stream and the two streams fed further at approximately atmospheric pressure. The essentially nitrogen-containing stream is mixed with an air stream to form a mixed nitrogen/air stream and the mixed-gas stream thus produced is brought to combustion chamber pressure in the compressor of the gas turbine, the combustion of the combustion gases in the combustion chamber of the gas turbine being carried out with the greater part of this compressed mixed-gas stream. (author) figs.

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR

International Nuclear Information System (INIS)

Unknown

2002-01-01

The objectives of this report period were to complete the development of the Gas Generator design, which was done; fabricate and test of the non-polluting unique power turbine drive gas Gas Generator, which has been postponed. Focus during this report period has been to complete the brazing and bonding necessary to fabricate the Gas Generator hardware, continue making preparations for fabricating and testing the Gas Generator, and continuing the fabrication of the Gas Generator hardware and ancillary hardware in preparation for the test program. Fabrication is more than 95% complete and is expected to conclude in early May 2002. the test schedule was affected by relocation of the testing to another test supplier. The target test date for hot fire testing is now not earlier than June 15, 2002

Safe Handling and Use of Flammable and Combustible Materials. Module SH-30. Safety and Health.

Science.gov (United States)

Center for Occupational Research and Development, Inc., Waco, TX.

This student module on safe handling and use of flammable and combustible materials is one of 50 modules concerned with job safety and health. This module introduces the student to the hazards of flammable and combustible materials and the measures necessary to control those hazards. Following the introduction, 14 objectives (each keyed to a page…

New generation of gas infrared point heaters

Energy Technology Data Exchange (ETDEWEB)

Schink, Damian [Pintsch Aben B.V., Dinslaken (Germany)

2011-11-15

It is more than thirty years since gas infrared heating for points was introduced on the railway network of what is now Deutsche Bahn. These installations have remained in service right through to the present, with virtually no modifications. More stringent requirements as regards availability, maintainability and remote monitoring have, however, led to the development of a new system of gas infrared heating for points - truly a new generation. (orig.)

Micro generation of electricity with gasification gas in a engine generator in dual mode; Microgeracao de eletricidade com gas de gaseificacao num motor gerador dual

Energy Technology Data Exchange (ETDEWEB)

Silva, Marcelo Jose da; Souza, Samuel Nelson Melegari de; Souza, Abel Alves de; Ricieri, Reinaldo P. [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PE (Brazil)], E-mail: marcelo_js07@hotmail.com

2010-07-01

Among the alternatives to the increase of world energy demand the use of biomass as energy source is one of the most promising as it contributes to reducing emissions of carbon dioxide in the atmosphere. Gasification is a process technology of biomass energy in a gaseous biofuel. The fuel gas got a low calorific value that can be used in diesel engine in dual mode for power generation in isolated communities. This study aimed to evaluate the reduction in the consumption of oil diesel an engine generator, using gas from gasification of wood. The engine generator brand used, it was a BRANCO, with direct injection power of 10 hp and mated to an electric generator 5,5 kW. The fuel gas was produced in a gasifier type co-current. The engine generator was put on load system from 0.5 kW to 3.5 kW through electric bank of heaters. For the oil diesel savings, the gas was injected mixed with intake air, as the oil diesel was normally injected by the injector of the engine (motor dual). The consumption od diesel was measured diesel by means of a precision scale. It was concluded that the engine converted to dual mode when using the gas for the gasification of wood showed a decrease in diesel consumption by up to 57%. (author)

Gas Generation from Actinide Oxide Materials

International Nuclear Information System (INIS)

Bailey, George; Bluhm, Elizabeth; Lyman, John; Mason, Richard; Paffett, Mark; Polansky, Gary; Roberson, G. D.; Sherman, Martin; Veirs, Kirk; Worl, Laura

2000-01-01

This document captures relevant work performed in support of stabilization, packaging, and long term storage of plutonium metals and oxides. It concentrates on the issue of gas generation with specific emphasis on gas pressure and composition. Even more specifically, it summarizes the basis for asserting that materials loaded into a 3013 container according to the requirements of the 3013 Standard (DOE-STD-3013-2000) cannot exceed the container design pressure within the time frames or environmental conditions of either storage or transportation. Presently, materials stabilized and packaged according to the 3013 Standard are to be transported in certified packages (the certification process for the 9975 and the SAFKEG has yet to be completed) that do not rely on the containment capabilities of the 3013 container. Even though no reliance is placed on that container, this document shows that it is highly likely that the containment function will be maintained not only in storage but also during transportation, including hypothetical accident conditions. Further, this document, by summarizing materials-related data on gas generation, can point those involved in preparing Safety Analysis Reports for Packages (SARPs) to additional information needed to assess the ability of the primary containment vessel to contain the contents and any reaction products that might reasonably be produced by the contents

Gas Generation from Actinide Oxide Materials

Energy Technology Data Exchange (ETDEWEB)

George Bailey; Elizabeth Bluhm; John Lyman; Richard Mason; Mark Paffett; Gary Polansky; G. D. Roberson; Martin Sherman; Kirk Veirs; Laura Worl

2000-12-01

This document captures relevant work performed in support of stabilization, packaging, and long term storage of plutonium metals and oxides. It concentrates on the issue of gas generation with specific emphasis on gas pressure and composition. Even more specifically, it summarizes the basis for asserting that materials loaded into a 3013 container according to the requirements of the 3013 Standard (DOE-STD-3013-2000) cannot exceed the container design pressure within the time frames or environmental conditions of either storage or transportation. Presently, materials stabilized and packaged according to the 3013 Standard are to be transported in certified packages (the certification process for the 9975 and the SAFKEG has yet to be completed) that do not rely on the containment capabilities of the 3013 container. Even though no reliance is placed on that container, this document shows that it is highly likely that the containment function will be maintained not only in storage but also during transportation, including hypothetical accident conditions. Further, this document, by summarizing materials-related data on gas generation, can point those involved in preparing Safety Analysis Reports for Packages (SARPs) to additional information needed to assess the ability of the primary containment vessel to contain the contents and any reaction products that might reasonably be produced by the contents.

Flammability limits: A review with emphasis on ethanol for aeronautical applications and description of the experimental procedure

International Nuclear Information System (INIS)

Coronado, Christian J.R.; Carvalho, João A.; Andrade, José C.; Cortez, Ely V.; Carvalho, Felipe S.; Santos, José C.; Mendiburu, Andrés Z.

2012-01-01

Highlights: ► Develops a comprehensive literature review on ethanol flammability limits. ► Difference in standard procedures lead to different experimental values of the flammability limits. ► Methodology for experiments to find the FL's of ethanol for aeronautical applications. - Abstract: The lower and upper flammability limits of a fuel are key tools for predicting fire, assessing the possibility of explosion, and designing protection systems. Knowledge about the risks involved with the explosion of both gaseous and vaporized liquid fuel mixtures with air is very important to guarantee safety in industrial, domestic, and aeronautical applications. Currently, most countries use various standard experimental tests, which lead to different experimental values for these limits. A comprehensive literature review of the flammability limits of combustible mixtures is developed here in order to organize the theoretical and practical knowledge of the subject. The main focus of this paper is the review of the flammability data of ethanol–air mixtures available in the literature. In addition, the description of methodology for experiments to find the upper and lower limits of flammability of ethanol for aeronautical applications is discussed. A heated spherical 20 L vessel was used. The mixtures were ignited with electrode rods placed in the center of the vessel, and the spark gap was 6.4 mm. LFL and the UFL were determined for ethanol (hydrated ethanol 96% °INPM) as functions of temperature for atmospheric pressure to compare results with data published in the scientific literature.

Method for Predicting Hypergolic Mixture Flammability Limits

Science.gov (United States)

2017-02-01

of all these phases. 15.  SUBJECT TERMS EOARD, rocket propulsion, combustion chemistry , energetic ionic liquids, flammability limits, fuel/oxidizer...Chemical Engineering Lab(UCP) This report is in support of the Integrated High Payoff Rocket Propulsion Technology (IHPRPT) Demonstration Program, which...formation at 298.15 K have been proposed by Osmont and co-workers [Osmont, 2007 and Osmont et al., 2007] by using quantum chemistry computations at

Hydrogen Generation Rate Model Calculation Input Data

International Nuclear Information System (INIS)

KUFAHL, M.A.

2000-01-01

This report documents the procedures and techniques utilized in the collection and analysis of analyte input data values in support of the flammable gas hazard safety analyses. This document represents the analyses of data current at the time of its writing and does not account for data available since then

Gas generation and migration in the shallow land disposal and preliminary impact analysis

International Nuclear Information System (INIS)

Nakai, Kunihiro

1996-01-01

As the latent effect in the case of gas generation in waste repositories, the damage of barriers by gas pressure, the pushing-out of contaminated water by pressure gas in waste repositories, the movement of radioactive gases containing H-3, C-14 and others, the explosion accompanying the release of combustible gas like hydrogen onto ground, and the effect to ground-water flow by gas movement or pressure are conceivable. The mechanism and the rate of gas generation, and the amount of the substances that generate gases in low level radioactive waste are explained. The models for evaluating the generation, accumulation and movement of gases are described. As to the evaluation of gas movement, the conditions for the evaluation, the results of evaluating gas permeation, the sensitivity of various parameters and so on are reported. Also the effects of radioactive gases, the pushing-out of pore water, the explosion of pressure-accumulating gases and the effect to ground-water flow were evaluated. Supposing the gas generation in shallow underground waste repositories, the model for evaluating the behaviors of gases and water in a whole system was made, and the preliminary evaluation was carried out. (K.I.)

Using a rainforest-flame forest mosaic to test the hypothesis that leaf and litter fuel flammability is under natural selection.

Science.gov (United States)

Clarke, Peter J; Prior, Lynda D; French, Ben J; Vincent, Ben; Knox, Kirsten J E; Bowman, David M J S

2014-12-01

We used a mosaic of infrequently burnt temperate rainforest and adjacent, frequently burnt eucalypt forests in temperate eastern Australia to test whether: (1) there were differences in flammability of fresh and dried foliage amongst congeners from contrasting habitats, (2) habitat flammability was related to regeneration strategy, (3) litter fuels were more flammable in frequently burnt forests, (4) the severity of a recent fire influenced the flammability of litter (as this would suggest fire feedbacks), and (5) microclimate contributed to differences in fire hazard amongst habitats. Leaf-level comparisons were made among 11 congeneric pairs from rainforest and eucalypt forests. Leaf-level ignitability, combustibility and sustainability were not consistently higher for taxa from frequently burnt eucalypt forests, nor were they higher for species with fire-driven recruitment. The bulk density of litter-bed fuels strongly influenced flammability, but eucalypt forest litter was not less dense than rainforest litter. Ignitability, combustibility and flame sustainability of community surface fuels (litter) were compared using fuel arrays with standardized fuel mass and moisture content. Forests previously burned at high fire severity did not have consistently higher litter flammability than those burned at lower severity or long unburned. Thus, contrary to the Mutch hypothesis, there was no evidence of higher flammability of litter fuels or leaves from frequently burnt eucalypt forests compared with infrequently burnt rainforests. We suggest the manifest pyrogenicity of eucalypt forests is not due to natural selection for more flammable foliage, but better explained by differences in crown openness and associated microclimatic differences.

Life-cycle comparison of greenhouse gas emissions and water consumption for coal and shale gas fired power generation in China

International Nuclear Information System (INIS)

Chang, Yuan; Huang, Runze; Ries, Robert J.; Masanet, Eric

2015-01-01

China has the world's largest shale gas reserves, which might enable it to pursue a new pathway for electricity generation. This study employed hybrid LCI (life cycle inventory) models to quantify the ETW (extraction-to-wire) GHG (greenhouse gas) emissions and water consumption per kWh of coal- and shale gas-fired electricity in China. Results suggest that a coal-to-shale gas shift and upgrading coal-fired power generation technologies could provide pathways to less GHG and water intensive power in China. Compared to different coal-fired generation technologies, the ETW GHG emissions intensity of gas-fired CC (combined cycle) technology is 530 g CO 2 e/kWh, which is 38–45% less than China's present coal-fired electricity. Gas-fired CT (combustion turbine) technology has the lowest ETW water consumption intensity at 960 g/kWh, which is 34–60% lower than China's present coal-fired electricity. The GHG-water tradeoff of the two gas-fired power generation technologies suggests that gas-fired power generation technologies should be selected based on regional-specific water resource availabilities and electricity demand fluctuations in China. However, the low price of coal-fired electricity, high cost of shale gas production, insufficient pipeline infrastructures, and multiple consumers of shale gas resources may serve as barriers to a coal-to-shale gas shift in China's power sector in the near term. - Highlights: • The GHG and water footprints of coal- and shale gas-fired electricity are estimated. • A coal-to-shale gas shift can enable less GHG and water intensive power in China. • The GHG emissions of shale gas-fired combined cycle technology is 530 g CO 2 e/kWh. • The water consumption of shale gas-fired combustion turbine technology is 960 g/kWh. • Shale gas-fired power generation technologies selection should be regional-specific

Test Plan for Measuring Ventilation Rates and Combustible Gas Levels in TWRS Active Catch Tanks

Energy Technology Data Exchange (ETDEWEB)

NGUYEN, D.M.

1999-10-25

The purpose of this sampling activity is to obtain data to support an initial evaluation of potential hazards due to the presence of combustible gas in catch tanks that are currently operated by the River Protection Project (RPP). Results of the hazard analysis will be used to support closure of the flammable gas unreviewed safety question for these facilities. The data collection will be conducted in accordance with the Tank Safety Screening Data Quality Objective (Dukelow et al. 1995). Combustible gas, ammonia, and organic vapor levels in the headspace of the catch tanks will be field-measured using hand-held instruments. If a combustible gas level measurement in a tank exceeds an established threshold, gas samples will he collected in SUMMA' canisters for more extensive laboratory analysis. In addition, ventilation rates of some catch tanks will be measured to evaluate removal of flammable gas by air flowing through the tanks. This test plan identifies the sample collection, laboratory analysis, quality assurance, and reporting objectives for this data collection effort. The plan also provides the procedures for field measurement of combustible gas concentrations and ventilation rates.

Modelling of gas generation in deep geological repositories after closure

International Nuclear Information System (INIS)

Poller, A.; Mayer, G.; Darcis M; Smith, P.

2016-12-01

In deep geological repositories for radioactive waste, significant quantities of gases will be generated in the long term as a result of various processes, notably the anaerobic corrosion of metals and the degradation of organic materials. Therefore, the impact of gas production on post-closure safety of the repositories needs to be assessed as part of a safety case. The present report provides a comprehensive description of the quantitative modelling of gas generation and associated water consumption during the post-closure phase of deep geological repositories in Opalinus Clay based on current scientific knowledge and on current preliminary repository designs. This includes a presentation of the modelling basis, namely the conceptual and mathematical models, the input data used, the computer tools developed, the relevant uncertainties and principal programme / design options, as well as the derivation, analysis and discussion of specific assessment cases. The modelling is carried out separately for the two main sources of gas, which are the emplaced waste including the disposal containers; and the construction materials. The contribution of construction materials to gas generation rates in emplacement tunnels for spent fuel (SF) and vitrified high-level waste (HLW) is significant during several thousand years after closure. In the long term, however, the corrosion of the disposal canisters, which are in the reference case assumed to be fabricated of carbon steel, accounts for the vast majority of the total gas produced in these tunnels. The contribution of construction materials in emplacement caverns for long lived intermediate-level waste (ILW) and low- and intermediate-level waste (L/ILW) to gas generation is generally small. In ILW emplacement caverns, gas generation is generally dominated by hydrogen generation from the corrosion of cast iron Mosaik-II waste containers for PWR internals and from the corrosion of aluminium in operational waste from the

Modelling of gas generation in deep geological repositories after closure

Energy Technology Data Exchange (ETDEWEB)

Poller, A. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Mayer, G.; Darcis M [AF-Consult Switzerland Ltd, Baden-Dättwil, (Switzerland); Smith, P. [Safety Assessment Management Ltd, Henley-On-Thames, Oxfordshire (United Kingdom)

2016-12-15

In deep geological repositories for radioactive waste, significant quantities of gases will be generated in the long term as a result of various processes, notably the anaerobic corrosion of metals and the degradation of organic materials. Therefore, the impact of gas production on post-closure safety of the repositories needs to be assessed as part of a safety case. The present report provides a comprehensive description of the quantitative modelling of gas generation and associated water consumption during the post-closure phase of deep geological repositories in Opalinus Clay based on current scientific knowledge and on current preliminary repository designs. This includes a presentation of the modelling basis, namely the conceptual and mathematical models, the input data used, the computer tools developed, the relevant uncertainties and principal programme / design options, as well as the derivation, analysis and discussion of specific assessment cases. The modelling is carried out separately for the two main sources of gas, which are the emplaced waste including the disposal containers; and the construction materials. The contribution of construction materials to gas generation rates in emplacement tunnels for spent fuel (SF) and vitrified high-level waste (HLW) is significant during several thousand years after closure. In the long term, however, the corrosion of the disposal canisters, which are in the reference case assumed to be fabricated of carbon steel, accounts for the vast majority of the total gas produced in these tunnels. The contribution of construction materials in emplacement caverns for long lived intermediate-level waste (ILW) and low- and intermediate-level waste (L/ILW) to gas generation is generally small. In ILW emplacement caverns, gas generation is generally dominated by hydrogen generation from the corrosion of cast iron Mosaik-II waste containers for PWR internals and from the corrosion of aluminium in operational waste from the

Technology of steam generators for gas-cooled reactors. Proceedings of a specialists' meeting

Energy Technology Data Exchange (ETDEWEB)

NONE

1988-07-01

The activity of the IAEA in the field of the technology of gas-cooled reactors was formalized by formation of an International Working Group on Gas-Cooled Reactors (IWGCR). The gas cooled reactor program considered by the IWGCR includes carbon-dioxide-cooled thermal reactors, helium cooled thermal high temperature reactors for power generation and for process heat applications and gas-cooled fast breeder reactors. This report covers the papers dealing with operating experience, steam generators for next generation of gas-cooled reactors, material development and corrosion problems, and thermohydraulics.

Technology of steam generators for gas-cooled reactors. Proceedings of a specialists' meeting

International Nuclear Information System (INIS)

1988-01-01

The activity of the IAEA in the field of the technology of gas-cooled reactors was formalized by formation of an International Working Group on Gas-Cooled Reactors (IWGCR). The gas cooled reactor program considered by the IWGCR includes carbon-dioxide-cooled thermal reactors, helium cooled thermal high temperature reactors for power generation and for process heat applications and gas-cooled fast breeder reactors. This report covers the papers dealing with operating experience, steam generators for next generation of gas-cooled reactors, material development and corrosion problems, and thermohydraulics

Chemical Safety Alert: Lightning Hazard to Facilities Handling Flammable Substances

Science.gov (United States)

Raises awareness about lightning strikes, which cause more death/injury and damage than all other environmental elements combined, so industry can take proper precautions to protect equipment and storage or process vessels containing flammable materials.

78 FR 42818 - SafetyAlert: Safety Alert: Risks Associated With Liquid Petroleum (LP) Gas Odor Fade

Science.gov (United States)

2013-07-17

... gas that under certain conditions is required to be odorized for leak detection. The purpose of this... detection of any unintended release or leak of the gas. LPG is highly flammable and dangerous to inhale in... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No...

Gas generation from low-level radioactive waste: Concerns for disposal

International Nuclear Information System (INIS)

Siskind, B.

1992-01-01

The Advisory Committee on Nuclear Waste (ACNW) has urged the Nuclear Regulatory Commission (NRC) to reexamine the topic of hydrogen gas generation from low-level radioactive waste (LLW) in closed spaces to ensure that the slow buildup of hydrogen from water-bearing wastes in sealed containers does not become a problem for long-term safe disposal. Brookhaven National Laboratory (BNL) has prepared a report, summarized in this paper, for the NRC to respond to these concerns. The paper discusses the range of values for G(H 2 ) reported for materials of relevance to LLW disposal; most of these values are in the range of 0.1 to 0.6. Most studies of radiolytic hydrogen generation indicate a leveling off of pressurization, probably because of chemical kinetics involving, in many cases, the radiolysis of water within the waste. Even if no leveling off occurs, realistic gas leakage rates (indicating poor closure by gaskets on drums and liners) will result in adequate relief of pressure for radiolytic gas generation from the majority of commercial sector LLW packages. Biodegradative gas generation, however, could pose a pressurization hazard even at realistic gas leakage rates. Recommendations include passive vents on LLW containers (as already specified for high integrity containers) and upper limits to the G values and/or the specific activity of the LLW

The Jarvis gas release incident

International Nuclear Information System (INIS)

Manocha, J.

1992-01-01

On 26 September, 1991, large volumes of natural gas were observed to be leaking from two water wells in the Town of Jarvis. Gas and water were being ejected from a drilled water well, at which a subsequent gas explosion occurred. Measurements of gas concentrations indicated levels far in excess of the lower flammability limit at several locations. Electrical power and natural gas services were cut off, and residents were evacuated. A state of emergency was declared, and gas was found to be flowing from water wells, around building foundations, and through other fractures in the ground. By 27 September the volumes of gas had reduced substantially, and by 30 September all residents had returned to their homes and the state of emergency was cancelled. The emergency response, possible pathways of natural gas into the aquifer, and public relations are discussed. It is felt that the likelihood of a similar incident occurring in the future is high. 11 figs

LIQUIFIED NATURAL GAS (LNG CARRIERS

Directory of Open Access Journals (Sweden)

Daniel Posavec

2010-12-01

Full Text Available Modern liquefied natural gas carriers are double-bottom ships classified according to the type of LNG tank. The tanks are specially designed to store natural gas cooled to -161°C, the boiling point of methane. Since LNG is highly flammable, special care must be taken when designing and operating the ship. The development of LNG carriers has begun in the middle of the twentieth century. LNG carrier storage space has gradually grown to the current maximum of 260000 m3. There are more than 300 LNG carriers currently in operation (the paper is published in Croatian.

Leakage analysis of fuel gas pipe in large LNG carrier engine room

Directory of Open Access Journals (Sweden)

CEN Zhuolun

2017-10-01

Full Text Available [Objectives] The electric propulsion dual-fuel engine is becoming dominant in newly built Liquefied Natural Gas(LNGcarriers. To avoid the potential risks that accompany the use of flammable and explosive boil-off gas,the performance of precise safety and reliability assessments is indispensable. [Methods] This research concerns the engine rooms of large LNG carriers which are propelled electrically by a dual-fuel engine. Possible fuel gas(natural gasleak cases in different areas of the engine room are simulated and analyzed. Five representative leak cases defined by leak form,leak location and leak rate are entered into a Computational Fluid Dynamics(CFDsimulation,in which the Reynolds stress model of Fluent software is adopted as the turbulence model. The results of the leaked gas distribution and ventilation velocity field are analyzed in combination to obtain the diffusion tendency and concentration distribution of leaked gas in different areas.[Results] Based on an analysis of the results,an optimized arrangement of flammable gas detectors is provided for the engine room, and the adoption of an explosion-proof exhaust fan is proven to be unnecessary.[Conclusions] These analysis methods can provide a reference for similar gas leakage scenarios occurring in confined ventilated spaces. In addition, the simulation results can be used to quantitatively assess potential fire or explosion damage in order to guide the design of structural reinforcements.

Investigation of the Extinguishing Features for Liquid Fuels and Organic Flammable Liquids Atomized by a Water Flow

Directory of Open Access Journals (Sweden)

Voytkov Ivan V.

2016-01-01

Full Text Available The processes of heat and mass transfer were investigated experimentally while moving and evaporating the atomized water flow in high-temperature combustion products of typical liquid fuels and organic flammable liquids: gasoline, kerosene, acetone, crude oil, industrial alcohol. We determined typical periods of liquid extinguishing by an atomized water flow of various dispersability. Data of the discharge of extinguishing medium corresponding to various parameters of atomization and duration of using the atomization devices was presented. It is shown that Um≈3.5 m/s is a minimal outflow velocity of droplets during moving while passing the distance of 1m in the high-temperature gas medium to stop the combustion of organic liquids.

Assessing and ranking the flammability of some ornamental plant species to select firewise plants for landscaping in WUI (SE France).

Science.gov (United States)

Ganteaume, A.; Jappiot, M.; Lampin, C.

2012-04-01

The increasing urbanization of Wildland-Urban Interfaces (WUI) as well as the high fire occurrence in these areas requires the assessment and the ranking of the flammability of the ornamental vegetation surrounding houses especially that planted in hedges. Thus, the flammability of seven species, among those most frequently planted in hedges in Provence (South-Eastern France), were studied at particle level and at dead surface fuel level (litters) under laboratory conditions. The flammability parameters (ignition frequency, time-to-ignition, flaming duration) of the very fine particles (live leaves and particles fire bench. Burning experiments using the epiradiator showed that live leaves of Phyllostachys sp., Photinia frasei and Prunus laurocerasus had the shortest time-to-ignition and the highest ignition frequency and flaming duration whereas Pittosporum tobira and Nerium oleander were the longest to ignite with a low frequency. Phyllostachys sp. and Nerium oleander litters were the shortest to ignite while Prunus laurocerasus litter had the lowest bulk density and long time-to-ignition, but high flame propagation. Photinia fraseri litter ignited frequently and had a high flame spread while Pittosporum tobira litter ignited the least frequently and for the shortest duration. Cupressus sempervirens litter had the highest bulk density and the longest flaming duration but the lowest flame propagation. Pyracantha coccinea litter was the longest to ignite and flame propagation was low but lasted a long time. Hierarchical cluster analysis performed on the flammability parameters of live leaves and of litters ranked the seven species in four distinct clusters from the most flammable (Prunus laurocerasus and Pyracantha coccinea) to the least flammable (Pittosporum tobira and Nerium oleander); the other species displaying two groups of intermediate flammabilities (Phyllostachys sp.- Photinia fraseri and Cupressus sempervirens ). The species with highly flammable

Gas generation in deep radioactive waste repositories: a review of processes, controls and models

International Nuclear Information System (INIS)

Jones, M.A.

1990-10-01

Gas generation within radioactive waste repositories may produce two general problems: 1) breaching of engineered and natural barriers due to high gas pressures; 2) enhanced radiological risk due to reduced groundwater travel times and/or greater aqueous or gaseous activities reaching the biosphere. As a result of these concerns, HMIP must be aware of the current status of relevant research, together with any associated deficiencies. This report addresses the current status of published research on near-field gas generation from worldwide sources and documents the important gas generating processes, the factors controlling them and models available to simulate them. In the absence of suitable models, outline technical specifications for corrosion and microbial degradation gas generation models are defined and the deficiencies in the current understanding of gas generation are highlighted; a conceptual research programme to correct these deficiencies is presented. (author)

Computer systems and software description for gas characterization system

International Nuclear Information System (INIS)

Vo, C.V.

1997-01-01

The Gas Characterization System Project was commissioned by TWRS management with funding from TWRS Safety, on December 1, 1994. The project objective is to establish an instrumentation system to measure flammable gas concentrations in the vapor space of selected watch list tanks, starting with tank AN-105 and AW-101. Data collected by this system is meant to support first tank characterization, then tank safety. System design is premised upon Characterization rather than mitigation, therefore redundancy is not required

Study of physical properties, gas generation and gas retention in simulated Hanford waste

International Nuclear Information System (INIS)

Bryan, S.A.; Pederson, L.R.; Scheele, R.D.

1993-04-01

The purpose of this study was to establish the chemical and physical processes responsible for the generation and retention of gases within high-level waste from Tank 101-SY on the Hanford Site. This research, conducted using simulated waste on a laboratory scale, supports the development of mitigation/remediation strategies for Tank 101-SY. Simulated waste formulations are based on actual waste compositions. Selected physical properties of the simulated waste are compared to properties of actual Tank 101-SY waste samples. Laboratory studies using aged simulated waste show that significant gas generation occurs thermally at current tank temperatures (∼60 degrees C). Gas compositions include the same gases produced in actual tank waste, primarily N 2 , N 2 O, and H 2 . Gas stoichiometries have been shown to be greatly influenced by several organic and inorganic constituents within the simulated waste. Retention of gases in the simulated waste is in the form of bubble attachment to solid particles. This attachment phenomenon is related to the presence of organic constituents (HEDTA, EDTA, and citrate) of the simulated waste. A mechanism is discussed that relates the gas bubble/particle interactions to the partially hydrophobic surface produced on the solids by the organic constituents

Greenhouse gas emissions from shale gas and coal for electricity generation in South Africa

Directory of Open Access Journals (Sweden)

Brett Cohen

2014-03-01

Full Text Available There is increased interest, both in South Africa and globally, in the use of shale gas for electricity and energy supply. The exploitation of shale gas is, however, not without controversy, because of the reported environmental impacts associated with its extraction. The focus of this article is on the greenhouse gas footprint of shale gas, which some literature suggests may be higher than what would have been expected as a consequence of the contribution of fugitive emissions during extraction, processing and transport. Based on some studies, it has been suggested that life-cycle emissions may be higher than those from coal-fired power. Here we review a number of studies and analyse the data to provide a view of the likely greenhouse gas emissions from producing electricity from shale gas, and compare these emissions to those of coal-fired power in South Africa. Consideration was given to critical assumptions that determine the relative performance of the two sources of feedstock for generating electricity � that is the global warming potential of methane and the extent of fugitive emissions. The present analysis suggests that a 100-year time horizon is appropriate in analysis related to climate change, over which period the relative contribution is lower than for shorter periods. The purpose is to limit temperature increase in the long term and the choice of metric should be appropriate. The analysis indicates that, regardless of the assumptions about fugitive emissions and the period over which global warming potential is assessed, shale gas has lower greenhouse gas emissions per MWh of electricity generated than coal. Depending on various factors, electricity from shale gas would have a specific emissions intensity between 0.3 tCO2/MWh and 0.6 tCO2/MWh, compared with about 1 tCO2/MWh for coal-fired electricity in South Africa.

Flammability Analysis For Actinide Oxides Packaged In 9975 Shipping Containers

Energy Technology Data Exchange (ETDEWEB)

Laurinat, James E.; Askew, Neal M.; Hensel, Steve J.

2013-03-21

Packaging options are evaluated for compliance with safety requirements for shipment of mixed actinide oxides packaged in a 9975 Primary Containment Vessel (PCV). Radiolytic gas generation rates, PCV internal gas pressures, and shipping windows (times to reach unacceptable gas compositions or pressures after closure of the PCV) are calculated for shipment of a 9975 PCV containing a plastic bottle filled with plutonium and uranium oxides with a selected isotopic composition. G-values for radiolytic hydrogen generation from adsorbed moisture are estimated from the results of gas generation tests for plutonium oxide and uranium oxide doped with curium-244. The radiolytic generation of hydrogen from the plastic bottle is calculated using a geometric model for alpha particle deposition in the bottle wall. The temperature of the PCV during shipment is estimated from the results of finite element heat transfer analyses.

Natural gas and electricity generation in New South Wales

International Nuclear Information System (INIS)

Webb, G.

2001-01-01

In its Profile of the Australian Electricity Industry, ABARE noted that NSW was the first State in Australia to unbundle the operations of its State owned electricity industry. The process commenced in 1991, when the Electricity Commission of NSW was renamed Pacific Power and reorganised into six generation and transmission sectors. The power generation fuel mix for NSW in 1999-2000 was as follows: black coal, 97 percent and natural gas, 3 percent. NSW has also imported some brown coal generated electricity from Victoria in recent years. The import of cheap brown coal power from this State due to a marked increase in the availability of brown coal base-load generators in the Latrobe Valley forced some surplus black coal generating capacity in NSW to be withdrawn from the marketplace. Four generating units were closed down in 1998 two 500 MW units at Liddell and two 300 MW units at Munmorah. Further prospects for natural gas are reported to be good; its share in the thermal electricity generation market is forecasted to rise from 3 percent in 1999-2000 to 12 percent in 2014-1015

Gas Generation from K East Basin Sludges - Series I Testing

International Nuclear Information System (INIS)

Delegard, Calvin H.; Bryan, Samuel A.; Schmidt, Andrew J.; Bredt, Paul R.; King, Christopher M.; Sell, Rachel L.; Burger, Leland L.; Silvers, Kurt L.

2000-01-01

This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor and canister sludge. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. The overall goals for this testing were to collect detailed gas generation rate and composition data to ascertain the quantity and reactivity of the metallic uranium (and other reactive species) present in the K Basin sludge. The gas generation evaluation included four large-scale vessels (850 ml) and eight small-scale vessels (30 ml) in an all-metal, leak tight system. The tests were conducted for several thousand hours at ambient and elevated temperatures (32 C, 40 C, 60 C, 80 C, and 95 C) to accelerated the reactions and provide conclusive gas generation data within a reasonable testing period. The sludge used for these tests was collected from the KE Basin floor and canister barrels (containing damaged spent fuel elements) using a consolidated sampling technique (i.e., material from several locations was combined to form ''consolidated samples''). Portions of these samples were sieved to separate particles greater than 250 m (P250) from particle less than 250 m (M250). This separation was performed to mimic the separation operations that are planned during the retrieval of certain K Basin sludge types and to gain a better understanding of how uranium metal is distributed in the sludge. The corrosion rate of the uranium metal particles in the sludge was found to agree reasonably well with corrosion rates reported in the literature

Cycling performance of lithium polymer cells assembled by in situ polymerization of a non-flammable ionic liquid monomer

International Nuclear Information System (INIS)

Lee, Yoon-Sung; Kim, Dong-Won

2013-01-01

Highlights: • Gel polymer electrolytes were synthesized by in situ polymerization of ionic liquid in the lithium polymer cells. • Flammability of the electrolyte was significantly reduced by polymerizing electrolyte containing a non-flammable ionic liquid monomer. • The cells assembled with polymeric ionic liquid-based electrolytes exhibited reversible cycling behavior with good capacity retention. -- Abstract: Lithium polymer cells composed of a lithium negative electrode and a LiCoO 2 positive electrode were assembled with a gel polymer electrolyte obtained by in situ polymerization of an electrolyte solution containing an ionic liquid monomer with vinyl groups. The polymerization of the electrolyte solution containing the non-flammable ionic liquid monomer resulted in a significant reduction of the flammability of the gel polymer electrolytes. The lithium polymer cell assembled with the stable gel polymer electrolyte delivered a discharge capacity of 134.3 mAh g −1 at ambient temperature and exhibited good capacity retention

Agricultural residues as fuel for producer gas generation

Energy Technology Data Exchange (ETDEWEB)

Hoeglund, C

1981-01-01

This paper reports on results from a series of tests with four different types of agricultural residues as fuel for producer gas generation. The fuels are coconut shells, coconut husks, pelletized wheat-straw and pressed sugar cane. The tests were made with a 73 Hp (50 kW) agricultural tractor diesel engine equipped with a standard gasifier developed for wood chips in Sweden, and run on a testbed at the Swedish National Machinery Testing Institute. The engine was operated on approximately 10% diesel oil and 90% producer gas. The gas composition, its calorific value and temperature, the pressure drop and the engine power were monitored. Detailed elementary analysis of the fuel and gas were carried out. Observations were also made regarding the important aspects of bridging and slagging in the gasifier. The tests confirmed that coconut shells make an excellent fuel for producer gas generation. After 8 hours of running no problems with slags and bridging were experienced. Coconut husks showed no bridging but some slag formation. The gasifier operated satisfactorily for this fuel. Pelletized wheat straw and pressed sugar cane appeared unsuitable as fuel in the unmodified test gasifier (Type F 300) due to slag formation. It is important to note, however, that the present test results are not optimal for any of the fuels used, the gasifier being designed for wood-chips and not for the test-fuels used. Tests using approximately modified gasifiers are planned for the future.

Spreaders, igniters, and burning shrubs: plant flammability explains novel fire dynamics in grass-invaded deserts.

Science.gov (United States)

Fuentes-Ramirez, Andres; Veldman, Joseph W; Holzapfel, Claus; Moloney, Kirk A

2016-10-01

Novel fire regimes are an important cause and consequence of global environmental change that involve interactions among biotic, climatic, and human components of ecosystems. Plant flammability is key to these interactions, yet few studies directly measure flammability or consider how multiple species with different flammabilities interact to produce novel fire regimes. Deserts of the southwestern United States are an ideal system for exploring how novel fire regimes can emerge when fire-promoting species invade ecosystems comprised of species that did not evolve with fire. In these deserts, exotic annual grasses provide fuel continuity across landscapes that did not historically burn. These fires often ignite a keystone desert shrub, the fire-intolerant creosote bush, Larrea tridentata (DC.) Coville. Ignition of Larrea is likely catalyzed by fuels produced by native plants that grow beneath the shrubs. We hypothesize that invasive and native species exhibit distinct flammability characteristics that in combination determine spatial patterns of fire spread and intensity. We measured flammability metrics of Larrea, two invasive grasses, Schismus arabicus and Bromus madritensis, and two native plants, the sub-shrub Ambrosia dumosa and the annual herb Amsinckia menziesii. Results of laboratory experiments show that the grasses carry fire quickly (1.32 cm/s), but burn for short duration (0.5 min) at low temperatures. In contrast, native plants spread fire slowly (0.12 cm/s), but burn up to eight times longer (4 min) and produced hotter fires. Additional experiments on the ignition requirements of Larrea suggest that native plants burn with sufficient temperature and duration to ignite dead Larrea branches (time to ignition, 2 min; temperature at ignition 692°C). Once burning, these dead branches ignite living branches in the upper portions of the shrub. Our study provides support for a conceptual model in which exotic grasses are "spreaders" of fire and native

FEBEX. Investigations on gas generation, release and migration

International Nuclear Information System (INIS)

Jockwer, Norbert; Wieczorek, Klaus

2008-06-01

The FEBEX project is based on the Spanish reference concept for the disposal of radioactive waste in crystalline rock, which considers the emplacement of the canisters enclosing the conditioned waste surrounded by clay barriers constructed of high-compacted bentonite blocks in horizontal drifts /ENR 957. The whole project consisted of an experimental and a modelling part. The experimental part itself was divided into the in-situ test, a mock-up test performed at the CIEMAT laboratory, and various small-scale laboratory tests. In the modelling part it was expected to develop and validate the thermo-hydro-mechanical (THM) and the thermo-hydro-chemical (THC) processes for the performance assessment of the near-field behaviour. GRS was only involved in the in-situ test and some additional laboratory work with regard to gas generation, gas migration, and pore pressure build-up in the buffer constructed of high-compacted bentonite blocks around the electrical heaters simulating the waste containers. The following topics are covered: installation and dismantling of the heater pipes; methods of gas generation and release measurement, summary of results and discussion

Price elasticity of natural gas demand in the power generation sector

International Nuclear Information System (INIS)

McArdle, P.F.

1990-01-01

Today, the demand for energy by the electric generation sector is highly competitive and price-responsive. Previous estimates of the price elasticity of natural gas demand in this sector have focused primarily on data from the 1960s and 1970s. Such estimates fail to take full account of economic, regulatory, and legislative developments that have altered the structure of the electric generation market during the 1980s. Structural changes include an increased ability of utilities to choose among generating options, the increase in non-utility generators, the amending of the Fuel Use Act, and a more competitive market for electricity. An accurate estimate of price elasticity requires a refocusing on data from the post-1983 period. The purpose of this paper is to answer two questions: how price responsive (elastic) is natural gas demand in this market; and what changes in natural gas demand elasticity have occurred over time

Comparison and evaluation of methods for the determination of flammability limits, applied to methane/hydrogen/air mixtures

International Nuclear Information System (INIS)

Schoor, F. van den; Hermanns, R.T.E.; Oijen, J.A. van; Verplaetsen, F.; Goey, L.P.H. de

2008-01-01

Different methods, both experimental and numerical, to determine the flammability limits are compared and evaluated, exemplified by a determination of the flammability limits of methane/hydrogen/air mixtures for hydrogen fuel molar fractions of 0, 0.2, 0.4 and 0.6, at atmospheric pressure and ambient temperature. Two different experimental methods are used. The first method uses a glass tube with visual observation of the flame, whereas the second method uses a closed spherical vessel with a pressure rise criterion to determine whether flame propagation has occurred. In addition to these experiments, the flammability limits are determined numerically. Unsteady planar and spherically expanding flames are calculated with a one-dimensional flame code with the inclusion of radiation heat loss in the optically thin limit. Comparison of the experimental results with the results of the planar flame calculations shows large differences, especially for lean mixtures. These differences increase with increasing hydrogen content in the fuel. Better agreement with the experimental results is found for the spherically expanding flame calculations. A limiting burning velocity of 5 cm/s is found to predict the upper flammability limit determined with the tube method very well, whereas the limiting flame temperature approach was found to give poorer agreement. Further analysis indicates that the neglect of flame front instabilities is the probable cause of the large differences between experimental and numerical results at the lower flammability limit

Non-Toxic, Non-Flammable, -80 C Phase Change Materials

Science.gov (United States)

Cutbirth, J. Michael

2013-01-01

The objective of this effort was to develop a non-toxic, non-flammable, -80 C phase change material (PCM) to be used in NASA's ICEPAC capsules for biological sample preservation in flight to and from Earth orbit. A temperature of about -68 C or lower is a critical temperature for maintaining stable cell, tissue, and cell fragment storage.

Power generation from landfill gas workshop discussion of Session 1

International Nuclear Information System (INIS)

Loning, A.; Bevan, G.; Moss, H.

1992-01-01

The discussion following presentations on the UK Dept. of Energy's involvement with power generation form landfill gas and the UK Government's attitude to pollution prevention from landfill gas power production is presented. The discussion focusses particularly on the Non-Fossil Fuel Obligation. (UK)

Study on gas turbines. Leading role of high efficiency power generation; Gas turbine kenkyu. Kokoritsu hatsuden no shuyaku wo nerau

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-01-31

This review summarizes research works of Central Research Institute of Electric Power Industry on gas turbines playing a leading role of high efficiency power generation. This article describes historical changes of gas turbine technology, changes and current status from the viewpoint of electric power industry, and development trend in various makers. Increase in the flow-in gas temperature, low NOx combustion technology, use of various fuels, and durability evaluation and improvement technology for high temperature parts are described as technological problems and development trends. The increase in temperature is indispensable for the improvement of efficiency. Materials having heat resistance, anticorrosion and strength are required. Accordingly, Ni-based single crystal super alloy has been developed. Developments of ceramic gas turbine and catalytic combustor are also described. The coal gasification combined power generation is expected as a new power generation technology having availability of various coals, high efficiency, and excellent environmental protection. Development of 1500 {degree}C class combustor for turbines has been promoted. Evaluation and improvement of durability of high temperature parts are also described. For the new utilization technology of gas turbines, repowering and compressed air storage gas turbine power generation technology are introduced. 92 figs., 14 tabs.

Technology on In-Situ Gas Generation to Recover Residual Oil Reserves

Energy Technology Data Exchange (ETDEWEB)

Sayavur Bakhtiyarov

2008-02-29

This final technical report covers the period October 1, 1995 to February 29, 2008. This chapter begins with an overview of the history of Enhanced Oil Recovery techniques and specifically, CO2 flood. Subsequent chapters conform to the manner consistent with the Activities, Tasks, and Sub-tasks of the project as originally provided in Exhibit C1 in the Project Management Plan dated September 20, 1995. These chapters summarize the objectives, status and conclusions of the major project activities performed during the project period. The report concludes by describing technology transfer activities stemming from the project and providing a reference list of all publications of original research work generated by the project team or by others regarding this project. The overall objective of this project was a final research and development in the United States a technology that was developed at the Institute for Geology and Development of Fossil Fuels in Moscow, Russia. Before the technology can be convincingly adopted by United States oil and gas producers, the laboratory research was conducted at Mew Mexico Institute of Mining and Technology. The experimental studies were conducted to measure the volume and the pressure of the CO{sub 2} gas generated according to the new Russian technology. Two experimental devices were designed, built and used at New Mexico Tech facilities for these purposes. The designed setup allowed initiating and controlling the reaction between the 'gas-yielding' (GY) and 'gas-forming' (GF) agents proposed by Russian technology. The temperature was controlled, and the generated gas pressure and volume were recorded during the reaction process. Additionally, the effect of surfactant addition on the effectiveness of the process was studied. An alternative GY reactant was tested in order to increase the efficiency of the CO2 gas generation process. The slim tube and the core flood experimental studies were conducted to define

Non-Flammable Crew Clothing Utilizing Phosphorus-Based Fire Retardant Polymers, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — For maintaining U.S. leadership role in space exploration, there is an urgent need to develop non-flammable shirts, shorts, sweaters, and jackets without...

A Flue Gas Tube for Thermoelectric Generator

DEFF Research Database (Denmark)

2013-01-01

The invention relates to a flue gas tube (FGT) (1) for generation of thermoelectric power having thermoelectric elements (8) that are integrated in the tube. The FTG may be used in combined heat and power (CHP) system (13) to produce directly electricity from waste heat from, e.g. a biomass boiler...

Low-Flammability PTFE for High-Oxygen Environments

Science.gov (United States)

Walle, E.; Fallon, B.; Sheppard, A.

1986-01-01

Modified forming process removes volatile combustible materials. Flammability of cable-wrapping tape reduced by altering tape-manufacturing process. In new manufacturing process, tape formed by proprietary process of screw extrusion, followed by washing in solvent and drying. Tape then wrapped as before. Spectrogram taken after extrusion, washing, and drying shows lower hydrocarbon content. PTFE formed by new process suited to oxygen-rich environments. Safe in liquid oxygen of Space Shuttle tank and in medical uses; thin-wall shrinkable tubing in hospital test equipment, surgical instruments, and implants.

The Efficiency of Non-Flammable Functional Underwear

Directory of Open Access Journals (Sweden)

Glombikova Viera

2014-09-01

Full Text Available This study evaluates the efficiency of non-flammable functional underwear used as a secondary heat barrier in extreme conditions. Five groups of knitted fabrics were analysed for flame resistance and selected physiological properties (water vapour permeability, air permeability, thermal resistance and liquid moisture transport by moisture management transport. The results indicated similar levels of flame resistance for the materials tested but show important differences in terms of physiological characteristics, namely liquid moisture transport, which influences the safety and comfort of protective clothing.

Effects of additives on thermal stability of Li ion cells

Science.gov (United States)

Doughty, Daniel H.; Roth, E. Peter; Crafts, Chris C.; Nagasubramanian, G.; Henriksen, Gary; Amine, Khalil

Li ion cells are being developed for high-power applications in hybrid electric vehicles, because these cells offer superior combination of power and energy density over current cell chemistries. Cells using this chemistry are proposed for battery systems in both internal combustion engine and fuel cell-powered hybrid electric vehicles. However, the safety of these cells needs to be understood and improved for eventual widespread commercial applications. The thermal-abuse response of Li ion cells has been improved by the incorporation of more stable anode carbons and electrolyte additives. Electrolyte solutions containing vinyl ethylene carbonate (VEC), triphenyl phosphate (TPP), tris(trifluoroethyl)phosphate (TFP) as well as some proprietary flame-retardant additives were evaluated. Test cells in the 18,650 configuration were built at Sandia National Laboratories using new stable electrode materials and electrolyte additives. A special test fixture was designed to allow determination of self-generated cell heating during a thermal ramp profile. The flammability of vented gas and expelled electrolyte was studied using a novel arrangement of a spark generator placed near the cell to ignite vent gas if a flammable gas mixture was present. Flammability of vent gas was somewhat reduced by the presence of certain additives. Accelerating rate calorimetry (ARC) was also used to characterize 18,650-size test cell heat and gas generation. Gas composition was analyzed by gas chromatography (GC) and was found to consist of CO 2, H 2, CO, methane, ethane, ethylene and small amounts of C1-C4 organic molecules.

An optimization model for natural gas supply portfolios of a power generation company

International Nuclear Information System (INIS)

Jirutitijaroen, Panida; Kim, Sujin; Kittithreerapronchai, Oran; Prina, José

2013-01-01

Highlights: ► An optimization model for daily operation of a natural gas-fired generation company is proposed. ► The model considers uncertainties in electricity price and natural gas price. ► The model is formulated to capture the hedging decisions by the company. ► The solution yields quantities of natural gas, generating schedule and purchasing quantities of electricity. ► Higher profit can be achieved by adapting inventory and production to the actual spot prices of natural gas and electricity. - Abstract: This paper considers a deregulated electricity market environment where a natural gas-fired generation company can engage in different types of contracts to manage its natural gas supply as well as trade on the electricity market. If the contracts are properly designed, they can protect the company from fluctuations in electricity price and demand, at some cost to the company’s expected profit. This reduction in profit can be mitigated by trading on the natural gas and electricity spot markets, but this trading activity may also sometimes result in losses. A stochastic programming model is formulated to capture the hedging decisions made by the company, as well as the interactions between the natural gas and electricity markets. The benefits offered by this approach for profit maximization in a variety of business scenarios, such as the case where the company can hold some amount of gas in storage are studied and presented. It is found that the stochastic model enables the company to optimize the electricity generation schedule and the natural gas consumption, including spot price transactions and gas storage management. Several managerial insights into the natural gas market, natural gas storage, and distribution profit are given

Gas generation from the irradiation of mortar

International Nuclear Information System (INIS)

Lewis, M.A.; Warren, D.W.

1989-01-01

A mortar formulation capable of immobilizing chloride salts with high levels of radioactivity is being developed. As part of the developmental effort, radiation effects are being investigated. The radiolytic generation of gas(es) from irradiated mortar formulations was determined for several formulations with variable salt loadings at several test temperatures. The irradiation of a mortar formulation consisting of cement, slag, fly ash, water and 0 to 10 wt % salt led to the generation of hydrogen. The rate of generation was approximately constant, steady state pressures were not attained and final pressures were comparatively high. Higher salt concentrations were correlated with higher hydrogen generation rates for experiments at ambient temperature while lower rates were observed at 120/degree/C. The irradiation of a mortar consisting of cement, fly ash, water and salt led to the radiolytic generation of both oxygen and hydrogen. The addition of 2 wt % FeS or CaS inhibited oxygen generation and changed the hydrogen production rate. 10 refs., 4 figs., 3 tabs

Status and integration of studies of gas generation in Hanford wastes

International Nuclear Information System (INIS)

Pederson, L.R.; Bryan, S.A.

1996-10-01

The purpose of this report is to review recent progress in determining the mechanism, kinetics, and stoichiometry of gas generation in Hanford waste tanks. Information has been gathered from the results of (1) laboratory studies with simulated wastes; (2) laboratory studies with actual waste core samples (Tanks SY-101 and SY-103); (3) studies of thermal and radiolytic reactions in the gas phase; (4) gas solubility evaluations; and (5) in-tank gas composition data. The results of laboratory studies using simulated wastes, which were aimed at determining chemical mechanisms responsible for gas generation, are summarized in Section 2. Emphasized are findings from work performed at the Georgia Institute of Technology (GIT), which was conducted under subcontract to Pacific Northwest National Laboratory (PNNL) and completed in FY 1996. Thermally activated pathways for the decomposition of hydroxyethylethylene-diaminetriacetic acid (HEDTA, trisodium salt) in simulated wastes were established by this work, among other accomplishments

Status and integration of studies of gas generation in Hanford wastes

Energy Technology Data Exchange (ETDEWEB)

Pederson, L.R.; Bryan, S.A.

1996-10-01

The purpose of this report is to review recent progress in determining the mechanism, kinetics, and stoichiometry of gas generation in Hanford waste tanks. Information has been gathered from the results of (1) laboratory studies with simulated wastes; (2) laboratory studies with actual waste core samples (Tanks SY-101 and SY-103); (3) studies of thermal and radiolytic reactions in the gas phase; (4) gas solubility evaluations; and (5) in-tank gas composition data. The results of laboratory studies using simulated wastes, which were aimed at determining chemical mechanisms responsible for gas generation, are summarized in Section 2. Emphasized are findings from work performed at the Georgia Institute of Technology (GIT), which was conducted under subcontract to Pacific Northwest National Laboratory (PNNL) and completed in FY 1996. Thermally activated pathways for the decomposition of hydroxyethylethylene-diaminetriacetic acid (HEDTA, trisodium salt) in simulated wastes were established by this work, among other accomplishments.

Certification of power generation from sewage gas

International Nuclear Information System (INIS)

Ronchetti, C.

2004-01-01

This article discusses the certification of power generated from sewage gas in packaged co-generation units in Switzerland. Since 2003, such electricity can be sold as 'green power' to consumers, who pay an additional charge for this ecologically generated power. Since the eco-balance of this electricity generated in wastewater treatment plant is considered as being excellent, the prestigious 'Naturemade Star' label has been awarded to it. This label sets most stringent requirements. The Canius wastewater treatment plant in the 'Lenzerheide' in eastern Switzerland is taken as an example to illustrate the procedure that has to be gone through to receive certification. This certification is carried out by independent auditors and guarantees that the 'green' electricity offered by the utility meets the high ecological criteria set by the label

Process for water-gas generation from degassed combustibles

Energy Technology Data Exchange (ETDEWEB)

1906-05-23

A process for water-gas generation in a continuous operation from degassed combustibles in the lower part of a vertical exterior-heated retort, whose middle part can serve to degas the combustibles, is described. It is characterized in that the water vapor employed is obtained by vaporizing water in the upper part of the retort by means of the waste heat from the heating gases, which had effected the coking of the combustibles before the water-gas recovery or after the latter.

Power-generating process of obtaining gas-energy carrier and reducer from coal

International Nuclear Information System (INIS)

Tleugabulov, S.; Duncheva, E.; Zubkevich, M.

1999-01-01

The manufacture of power-generating gas has the important economic value for Kazakhstan having large territory, raw and fuel resources especially power coal and clean coal wastes. The technology of reception of gas-energy carrier and reducer from power coal is developed. The basic product of technological process is heated reducing gas. Reducing potential of the gas is characterized by a volumetric share of components (CO+H 2 )-RC in relation to volume of whole mix of gases received with gasification of coal. The value of parameter RC is regulated by a degree of enrichment of air by oxygen r 0 , and the temperature - by the charge of a parity of endothermic reaction in the chamber of gas regeneration. The dependence of the gas structure and temperature on the degree of enrichment of air by oxygen is shown and the circuit of the gas generator is given. (author)

Calculating the flue gas dew point for raw brown coal fired steam generators

Energy Technology Data Exchange (ETDEWEB)

Schinkel, W.

1977-01-01

The paper analyzes parameters influencing the sulfuric acid dew point in flue gas of steam generators. Sulfur content and alkaline earths content in the fuel air ratio during combustion, fly ash content in the flue gas (which absorbs sulfur dioxide and sulfur trioxide) and combustion conditions in steam generators are relevant parameters in the combustion process. A thermodynamic and reaction kinetic calculation of the sulfuric acid dew point is, however, not yet possible. A statistical evaluation of dew point measurements in steam generators is, therefore, employed. Various diagrams show results of dew point measurements carried out at generators with steam capacities ranging from 40 to 660 t/h, which demonstrate relations of these parameters to flue gas dew points, in particular the relative sulfur content (sulfur content in the raw brown coal compared to coal ash content and alkaline earths content). A function is derived for the conversion of fuel sulfur to sulfur trioxide. A diagram presents the relation of the flue gas dew point to partial pressures of sulfuric acid and steam. Direct calculation of the flue gas dew point was achieved by the proposed method. It is applied in steam generator design. (17 refs.)

Seeded inert gas driven disk generator

International Nuclear Information System (INIS)

Joshi, N.K.; Venkatramani, N.; Rohatgi, V.K.

1987-01-01

This report outlines the present status of work being carried out in closed cycle MHD and disk generators. It gives the basic principles and discusses a proposal for setting up an experimental facility to study nonequilibrium plasmas using an inert gas driven disk generator. Disk geometry is a near ideal geometry for plasma studies since it has single or few pair electrodes combined with near perfect insulating walls. The proposed outlay of facility with components and subsystem is given. The facility may also be used to study the concept of fully ionized seed and to develop advanced diagnostic techniques. The absic equation describing the working parameters of such a system is also given in the Appendix. (author). 57 refs

Continuous organic waste digester and methane gas generator

Energy Technology Data Exchange (ETDEWEB)

Araneta, V.A.

1979-01-01

A patent on the construction of a utility model of an industrial product of a continuous organic-waste digester and methane-gas generator is described. It comprises an airtight chamber to receive slurry of organic waste; a gas-water scrubber to purge carbon dioxide, odor-omitting gases and froth or scrum from newly formed methane gas evolving from said slurry of organic wastes; and two dually functioning slurry-feed and -discharge pipes connected to a reversible pump. It has one pipe with an opening at the base of an airtight chamber and the other pipe with up-ended openings below the fluid level of the slurry to be accumulated in the airtight chamber.

Modeling of microbial gas generation: application to the eastern Mediterranean “Biogenic Play”

Energy Technology Data Exchange (ETDEWEB)

Schneider, M.; Dubille, M.; Montadert, L.

2016-07-01

Biogenic gas is becoming increasingly important as an exploration target in the petroleum industry because it occurs in geologically predictable circumstances and in large quantities at shallow depths as free gas or gas hydrates. As accumulations of biogenic gas result in a subtle synchronization between early generation and early trapping, we integrated a macroscopic model of microbial gas generation within a 3D basin and petroleum system forward simulator. The macroscopic model is based on a microscopic model, which consists in a 1D sedimentary column that accounts for sedimentation, compaction, Darcy flow and Diffusion flow. The organic carbon is the only non-soluble element considered in this version of the model. The dissolved elements are O2, SO4 2-, H2, CH3COOH, and CH4. Methane is dissolved in water or present as a free phase if its concentration exceeds its solubility at given pressure and temperature. In this microscopic model, the transformation of substrate into biomass is described through a set of logistic equations coupled with the transport equations (advection and diffusion). Based on the microscopic considerations we developed the macroscopic model of low maturity/biogenic gas generation in which hydrocarbons are generated through first order kinetic reactions at low maturity. This macroscopic model is adapted to petroleum system modeling at basin scale with TemisFlow®, which aims to understand and predict hydrocarbon generation, migration, and accumulation. It is composed of: i) A source rock criteria which allow defining the biogenic gas source rocks potential and ii) A kinetic model of methane generation. The previous model has been successfully applied on different basins such as the Carupano Basin from the offshore Venezuela, the Magdalena Delta (offshore Colombia) and the offshore Vietnam where direct observations of low-maturity gas were available. Furthermore, it has been applied in the offshore Lebanon in order to check the viability of

Thermal-maturity limit for primary thermogenic-gas generation from humic coals as determined by hydrous pyrolysis

Science.gov (United States)

Lewan, Michael; Kotarba, M.J.

2014-01-01

Hydrous-pyrolysis experiments at 360°C (680°F) for 72 h were conducted on 53 humic coals representing ranks from lignite through anthracite to determine the upper maturity limit for hydrocarbon-gas generation from their kerogen and associated bitumen (i.e., primary gas generation). These experimental conditions are below those needed for oil cracking to ensure that generated gas was not derived from the decomposition of expelled oil generated from some of the coals (i.e., secondary gas generation). Experimental results showed that generation of hydrocarbon gas ends before a vitrinite reflectance of 2.0%. This reflectance is equivalent to Rock-Eval maximum-yield temperature and hydrogen indices (HIs) of 555°C (1031°F) and 35 mg/g total organic carbon (TOC), respectively. At these maturity levels, essentially no soluble bitumen is present in the coals before or after hydrous pyrolysis. The equivalent kerogen atomic H/C ratio is 0.50 at the primary gas-generation limit and indicates that no alkyl moieties are remaining to source hydrocarbon gases. The convergence of atomic H/C ratios of type-II and -I kerogen to this same value at a reflectance of indicates that the primary gas-generation limits for humic coal and type-III kerogen also apply to oil-prone kerogen. Although gas generation from source rocks does not exceed vitrinite reflectance values greater than , trapped hydrocarbon gases can remain stable at higher reflectance values. Distinguishing trapped gas from generated gas in hydrous-pyrolysis experiments is readily determined by of the hydrocarbon gases when a -depleted water is used in the experiments. Water serves as a source of hydrogen in hydrous pyrolysis and, as a result, the use of -depleted water is reflected in the generated gases but not pre-existing trapped gases.

Flammability characteristics of combustible gases and vapors

Energy Technology Data Exchange (ETDEWEB)

Zabetakis, M. G. [Bureau of Mines, Pittsburgh, PA (United States)

1964-05-01

This is a summary of the available limit of flammability, autoignition and burning-rate data for more than 200 combustible gases and vapors in air and other oxidants, as well as of empirical rules and graphs that can be used to predict similar data for thousands of other combustibles under a variety of environmental conditions. Spec$c data are presented on the paraffinic, unsaturated, aromatic, and alicyclic hydrocarbons, alcohols, ethers, aldehydes, ketones, and sulfur compounds, and an assortment of fuels, fuel blends, hydraulic fluids, engine oils, and miscellaneous combustible gases and vapors.

A preliminary study on the thermal conductivity and flammability of WPC based on some tropical woods

International Nuclear Information System (INIS)

Chia, L.H.L.; Chua, P.H.; Lee, E.E.N.

1985-01-01

Selected local woods and their wood-polymer combinations or composites (WPC) were tested for their thermal conductivity and their fire resistance. WPC were prepared by polymerizing monomers 'in situ' in oven dried woods by gamma radiation. The monomers included acrylonitrile (AN), 60% styrene-40% acrylonitrile (STAN), methyl methacrylate (MMA), 95% methyl methacrylate-5% dioxane (MD), and vinylidene chloride (VDC). A reduction in thermal conductivity was exhibited by all the composites prepared. W-PAN showed the greatest reduction in thermal conductivity and W-PSTAN in general showed the least. An explanation is suggested for this behaviour. The polymers PMMA and PMD were found to enhance flammability of the woods while PVDC, PAN, and PSTAN imparted fire resistance to the woods. Of the six local woods studied, Ramin-and-Keruing-polymer composites showed the highest flammable tendencies obtained. The correlation of thermal conductivity to flammability is discussed. (author)

Natural gas as a public utilities' generator for market orientation

International Nuclear Information System (INIS)

Delnoij, J.

1995-01-01

The forthcoming free market for the energy sector in Europe is discussed. The author (retiring chairman of KVGN) advocates strengthening the collective market position of energy distribution companies and of the total gas sector, e.g. by continuing the combination of gas distribution and gas purchase and by increased tuning of research and market developments. Energy distribution companies have to strengthen the relation with their customers and set explicit quality objectives. The author also supported competition between the different forms of energy on the energy market and the strive of the gas sector to substitute polluting energy carriers, and electricity generated from these low-efficient energy carriers, by gas

Metathesis in the generation of low-temperature gas in marine shales

Directory of Open Access Journals (Sweden)

Jarvie Daniel M

2010-01-01

Full Text Available Abstract The recent report of low-temperature catalytic gas from marine shales took on additional significance with the subsequent disclosure of natural gas and low-temperature gas at or near thermodynamic equilibrium in methane, ethane, and propane. It is important because thermal cracking, the presumed source of natural gas, cannot generate these hydrocarbons at equilibrium nor can it bring them to equilibrium over geologic time. The source of equilibrium and the source of natural gas are either the same (generation under equilibrium control or closely associated. Here we report the catalytic interconversion of hydrocarbons (metathesis as the source of equilibrium in experiments with Cretaceous Mowry shale at 100°C. Focus was on two metathetic equilibria: methane, ethane, and propane, reported earlier, Q (K = [(C1*(C3]/[(C22], and between these hydrocarbons and n-butane, Q* (K = [(C1*(n-C4]/[(C2*(C3], reported here for the first time. Two observations stand out. Initial hydrocarbon products are near equilibrium and have maximum average molecular weights (AMW. Over time, products fall from equilibrium and AMW in concert. It is consistent with metathesis splitting olefin intermediates [Cn] to smaller intermediates (fission as gas generation creates open catalytic sites ([ ]: [Cn] + [ ] → [Cn-m] + [Cm]. Fission rates increasing exponentially with olefin molecular weight could contribute to these effects. AMW would fall over time, and selective fission of [C3] and [n-C4] would draw Q and Q* from equilibrium. The results support metathesis as the source of thermodynamic equilibrium in natural gas.

Reference Material Kydex(registered trademark)-100 Test Data Message for Flammability Testing

Science.gov (United States)

Engel, Carl D.; Richardson, Erin; Davis, Eddie

2003-01-01

The Marshall Space Flight Center (MSFC) Materials and Processes Technical Information System (MAPTIS) database contains, as an engineering resource, a large amount of material test data carefully obtained and recorded over a number of years. Flammability test data obtained using Test 1 of NASA-STD-6001 is a significant component of this database. NASA-STD-6001 recommends that Kydex 100 be used as a reference material for testing certification and for comparison between test facilities in the round-robin certification testing that occurs every 2 years. As a result of these regular activities, a large volume of test data is recorded within the MAPTIS database. The activity described in this technical report was undertaken to mine the database, recover flammability (Test 1) Kydex 100 data, and review the lessons learned from analysis of these data.

Study related to the generation of the conditional intensities of ideal Bose-gas

International Nuclear Information System (INIS)

Al-Oklah, H.

2007-01-01

In this paper, we will answer on the following question: Are there any conditions on the chemical potential and temperature of an ideal BOSE gas when generating the conditional intensities of ideal Bose-gas, and will the position distribution of the ideal Bose-gas be a Gibbs-process. The study shows that there should be no conditions on the chemical potential and thermodynamical temperature of an ideal BOSE gas when we generate the conditional intensities of ideal Bose-gas except that the fundamental conditions, the chemical potential is negative and the inverse temperature is positive. Thus the position distribution of the ideal Bose-gas may only be a Gibbs-process, in the special case when the thermodynamical temperature of the ideal BOSE gas tends to the absolute zero. (author)

Flammability of polypropylene/organoclay nanocomposites

International Nuclear Information System (INIS)

Alves, Tatianny Soares; Barbosa, Renata; Carvalho, Laura Hecker de; Canedo, Eduardo Luis

2014-01-01

The flammabilities of nanocomposites made with three polypropylene grades (homo and copolymers) with 5 wt % of organoclay (Cloisite 20A), 5 or 15 wt % of maleated polypropylene as compatibilizer, and 0, 0.5 or 1 wt % of cis-13-docosenamide (Erucamide) as co-intercalant, were studied using the horizontal burning test UL94HB. Masterbatches prepared in an internal mixer were diluted in the polypropylene matrix using a corotating twin-screw extruder, with different screw configurations and operating at 240 or 480 rpm. Results indicate that the high burning rate of the composites was not affected by the processing conditions. For all formulations was observed a significant reduction in smoke release, lack of dripping and the formation of a char surface layer, that protected the core of the samples. (author)

A small capacity co generative gas-turbine plant in factory AD 'Komuna' - Skopje (Macedonia)

International Nuclear Information System (INIS)

Dimitrov, Konstantin; Armenski, Slave; Tashevski, Done

2000-01-01

The factory AD 'Komuna' -Skopje (Macedonia), has two steam block boilers, type ST 800 for steam production for process and space heating. The factory satisfies the electricity needs from the national grid. By the use of natural gas like fuel it is possible to produce electrical energy in its own co generative gas turbine plant. In this article, a co generative plant with small-scale gas turbine for electricity production is analyzed . The gas from gas turbine have been introduce in the steam block boiler. Also, a natural gas consumption, the electricity production, total investment and payback period of investment are determined. (Authors)

Responding to Terrorist Incidents in Your Community: Flammable-Liquid Fire Fighting Techniques for Municipal and Rural Firefighters

Energy Technology Data Exchange (ETDEWEB)

Denise Baclawski

2010-03-08

The University of Nevada, Reno Fire Science Academy (FSA) applied for grant funding to develop and deliver programs for municipal, rural, and volunteer firefighters. The FSA specializes in preparing responders for a variety of emergency events, including flammable liquid fires resulting from accidents, intentional acts, or natural disasters. Live fire training on full scale burnable props is the hallmark of FSA training, allowing responders to practice critical skills in a realistic, yet safe environment. Unfortunately, flammable liquid live fire training is often not accessible to municipal, rural, or volunteer firefighters due to limited department training budgets, even though most department personnel will be exposed to flammable liquid fire incidents during the course of their careers. In response to this training need, the FSA developed a course during the first year of the grant (Year One), Responding to Terrorist Incidents in Your Community: Flammable-Liquid Fire Fighting Techniques for Municipal and Rural Firefighters. During the three years of the grant, a total of 2,029 emergency responders received this training. In Year Three, two new courses, a train-the-trainer for Responding to Terrorist Incidents in Your Community and Management of Large-Scale Disasters for Public Officials were developed and pilot tested during the Real-World Disaster Management Conference held at the FSA in June of 2007. Two research projects were conducted during Years Two and Three. The first, conducted over a two year period, evaluated student surveys regarding the value of the flammable liquids training received. The second was a needs assessment conducted for rural Nevada. Both projects provided important feedback and a basis for curricula development and improvements.

Electricity generation with natural gas or with uranium?

International Nuclear Information System (INIS)

Villanueva M, C.

2009-10-01

The program of works and investments of electric sector that actualize each year the Federal Commission of Electricity, include to the projects of electric power generating stations that will begin its commercial operation inside the horizon of the next ten years, in order to satisfy opportunely with appropriate reservation margins the demand of power and energy in the national interconnected system that grows year to year. In spite of its inherent advantages, in the electric sector prospective 2008-2017 are not considered explicitly to the nuclear power plants, except for the small amplification of capacity of nuclear power plant of Laguna Verde, that already is executing. In this context, the objective of this work is to present and to discuss arguments to favor and against the combined cycle and nuclear technologies, to indicate the risks and disadvantages in that it incurs the electric sector when leaning on so disproportionately on the fossil fuels for the electricity generation, in particular the natural gas, deferring to an indefinite future the installation of nuclear plants whose proven technology is economic, sure, clean and reliable and it contributes decisively to the national energy security. To mitigate the harmful effects of excessive dependence on natural gas to generate electric power, was propose alternatives to the expansion program of electric sector to year 2017, which would have as benefits the decrease of the annual total cost of electric power supply for public service, the significant reduction of natural gas imports and emissions reduction of CO 2 to the atmosphere. (Author)

Estimating retained gas volumes in the Hanford tanks using waste level measurements

International Nuclear Information System (INIS)

Whitney, P.D.; Chen, G.; Gauglitz, P.A.; Meyer, P.A.; Miller, N.E.

1997-09-01

The Hanford site is home to 177 large, underground nuclear waste storage tanks. Safety and environmental concerns surround these tanks and their contents. One such concern is the propensity for the waste in these tanks to generate and trap flammable gases. This report focuses on understanding and improving the quality of retained gas volume estimates derived from tank waste level measurements. While direct measurements of gas volume are available for a small number of the Hanford tanks, the increasingly wide availability of tank waste level measurements provides an opportunity for less expensive (than direct gas volume measurement) assessment of gas hazard for the Hanford tanks. Retained gas in the tank waste is inferred from level measurements -- either long-term increase in the tank waste level, or fluctuations in tank waste level with atmospheric pressure changes. This report concentrates on the latter phenomena. As atmospheric pressure increases, the pressure on the gas in the tank waste increases, resulting in a level decrease (as long as the tank waste is open-quotes softclose quotes enough). Tanks with waste levels exhibiting fluctuations inversely correlated with atmospheric pressure fluctuations were catalogued in an earlier study. Additionally, models incorporating ideal-gas law behavior and waste material properties have been proposed. These models explicitly relate the retained gas volume in the tank with the magnitude of the waste level fluctuations, dL/dP. This report describes how these models compare with the tank waste level measurements

Bottoming micro-Rankine cycles for micro-gas turbines

International Nuclear Information System (INIS)

Invernizzi, Costante; Iora, Paolo; Silva, Paolo

2007-01-01

This paper investigates the possibility of enhancing the performances of micro-gas turbines through the addition of a bottoming organic Rankine cycle which recovers the thermal power of the exhaust gases typically available in the range of 250-300 o C. The ORC cycles are particularly suitable for the recovery of heat from sources at variable temperatures, and for the generation of medium to small electric power. With reference to a micro-gas turbine with a size of about 100 kWe, a combined configuration could increase the net electric power by about 1/3, yielding an increase of the electrical efficiency of up to 40%. A specific analysis of the characteristics of different classes of working fluids is carried out in order to define a procedure to select the most appropriate fluid, capable of satisfying both environmental (ozone depletion potential, global warming potential) and technical (flammability, toxicity, fluid critical temperature and molecular complexity) concerns. Afterwards, a thermodynamic analysis is performed to ascertain the most favourable cycle thermodynamic conditions, from the point of view of heat recovery. Furthermore, a preliminary design of the ORC turbine (number of stages, outer diameter and rotational speed) is carried out

Screening the Hanford tanks for trapped gas

International Nuclear Information System (INIS)

Whitney, P.

1995-10-01

The Hanford Site is home to 177 large, underground nuclear waste storage tanks. Hydrogen gas is generated within the waste in these tanks. This document presents the results of a screening of Hanford's nuclear waste storage tanks for the presence of gas trapped in the waste. The method used for the screening is to look for an inverse correlation between waste level measurements and ambient atmospheric pressure. If the waste level in a tank decreases with an increase in ambient atmospheric pressure, then the compressibility may be attributed to gas trapped within the waste. In this report, this methodology is not used to estimate the volume of gas trapped in the waste. The waste level measurements used in this study were made primarily to monitor the tanks for leaks and intrusions. Four measurement devices are widely used in these tanks. Three of these measure the level of the waste surface. The remaining device measures from within a well embedded in the waste, thereby monitoring the liquid level even if the liquid level is below a dry waste crust. In the past, a steady rise in waste level has been taken as an indicator of trapped gas. This indicator is not part of the screening calculation described in this report; however, a possible explanation for the rise is given by the mathematical relation between atmospheric pressure and waste level used to support the screening calculation. The screening was applied to data from each measurement device in each tank. If any of these data for a single tank indicated trapped gas, that tank was flagged by this screening process. A total of 58 of the 177 Hanford tanks were flagged as containing trapped gas, including 21 of the 25 tanks currently on the flammable gas watch list

29 CFR 1910.107 - Spray finishing using flammable and combustible materials.

Science.gov (United States)

2010-07-01

... drying apparatus and electrical connections and wiring thereto shall not be located within spray... apparatus, the drying apparatus, and the ventilating system of the spray enclosure shall be equipped with... 29 Labor 5 2010-07-01 2010-07-01 false Spray finishing using flammable and combustible materials...

Fuel prices, emission standards, and generation costs for coal vs natural gas power plants.

Science.gov (United States)

Pratson, Lincoln F; Haerer, Drew; Patiño-Echeverri, Dalia

2013-05-07

Low natural gas prices and stricter, federal emission regulations are promoting a shift away from coal power plants and toward natural gas plants as the lowest-cost means of generating electricity in the United States. By estimating the cost of electricity generation (COE) for 304 coal and 358 natural gas plants, we show that the economic viability of 9% of current coal capacity is challenged by low natural gas prices, while another 56% would be challenged by the stricter emission regulations. Under the current regulations, coal plants would again become the dominant least-cost generation option should the ratio of average natural gas to coal prices (NG2CP) rise to 1.8 (it was 1.42 in February 2012). If the more stringent emission standards are enforced, however, natural gas plants would remain cost competitive with a majority of coal plants for NG2CPs up to 4.3.

Flammability and thermal properties studies of nonwoven flax reinforced acrylic based polyester composites

Science.gov (United States)

Rasyid, M. F. Ahmad; Salim, M. S.; Akil, H. M.; Ishak, Z. A. Mohd.

2017-12-01

In the pursuit of green and more sustainable product, natural fibre reinforced composites originating from renewable resources has gained interest in recent years. These natural fibres exhibit good mechanical properties, low production costs, and good environmental properties. However, one of the disadvantages of natural fibre reinforced composites is their high flammability that limits their application in many fields. Within this research, the effect of sodium silicate on the flammability and thermal properties of flax reinforced acrylic based polyester composites has been investigated. Sodium silicate is applied as binder and flame retardant system in impregnation process of the natural flax fiber mats. The addition of sodium silicate significantly improved the flame retardant efficiency but reduced the degree of crosslinking of the composites.

WIPP panel simulations with gas generation

International Nuclear Information System (INIS)

DeVries, K.L.; Callahan, G.D.; Munson, D.E.

1996-01-01

An important issue in nuclear waste repository performance is the potential for fracture development resulting in pathways for release of radionuclides beyond the confines of the repository. A series of demonstration calculations using structural finite element analyses are presented here to examine the effect of internal gas generation on the response of a sealed repository. From the calculated stress fields, the most probable location for a fracture to develop was determined to be within the pillars interior to the repository for the range of parameter values considered. If a fracture interconnects the rooms and panels of the repository, fracture opening produces significant additional void volume to limit the excess gas pressure to less than 1.0 MPa above the overburden pressure. Consequently, the potential for additional fracture development into the barrier pillar is greatly reduced, which provides further confidence that the waste will be contained within the repository

LBA-ECO LC-02 Forest Flammability Data, Catuaba Experimental Farm, Acre, Brazil: 1998

Data.gov (United States)

National Aeronautics and Space Administration — This data set provides the results of controlled burns conducted to assess the flammability of mature forests on the Catuaba Experimental Farm of the Federal...

LBA-ECO LC-02 Forest Flammability Data, Catuaba Experimental Farm, Acre, Brazil: 1998

Data.gov (United States)

National Aeronautics and Space Administration — ABSTRACT: This data set provides the results of controlled burns conducted to assess the flammability of mature forests on the Catuaba Experimental Farm of the...

Drought Resilience of Water Supplies for Shale Gas Extraction and Related Power Generation in Texas

Science.gov (United States)

Reedy, R. C.; Scanlon, B. R.; Nicot, J. P.; Uhlman, K.

2014-12-01

There is considerable concern about water availability to support energy production in Texas, particularly considering that many of the shale plays are in semiarid areas of Texas and the state experienced the most extreme drought on record in 2011. The Eagle Ford shale play provides an excellent case study. Hydraulic fracturing water use for shale gas extraction in the play totaled ~ 12 billion gallons (bgal) in 2012, representing ~7 - 10% of total water use in the 16 county play area. The dominant source of water is groundwater which is not highly vulnerable to drought from a recharge perspective because water is primarily stored in the confined portion of aquifers that were recharged thousands of years ago. Water supply drought vulnerability results primarily from increased water use for irrigation. Irrigation water use in the Eagle Ford play was 30 billion gallons higher in the 2011 drought year relative to 2010. Recent trends toward increased use of brackish groundwater for shale gas extraction in the Eagle Ford also reduce pressure on fresh water resources. Evaluating the impacts of natural gas development on water resources should consider the use of natural gas in power generation, which now represents 50% of power generation in Texas. Water consumed in extracting the natural gas required for power generation is equivalent to ~7% of the water consumed in cooling these power plants in the state. However, natural gas production from shale plays can be overall beneficial in terms of water resources in the state because natural gas combined cycle power generation decreases water consumption by ~60% relative to traditional coal, nuclear, and natural gas plants that use steam turbine generation. This reduced water consumption enhances drought resilience of power generation in the state. In addition, natural gas combined cycle plants provide peaking capacity that complements increasing renewable wind generation which has no cooling water requirement. However, water

Explosion protection for vehicles intended for the transport of flammable gases and liquids--an investigation into technical and operational basics.

Science.gov (United States)

Förster, Hans; Günther, Werner

2009-05-30

In Europe, the transport of flammable gases and liquids in tanks has been impacted by new developments: for example, the introduction of the vapour-balancing technique on a broad scale and the steady increase in the application of electronic components with their own power sources; furthermore, new regulatory policies like the ATEX Directives are being enforced in the European Union. With this background in mind, the present investigation aims to provide a basis for future developments of the relevant explosion protection regulations in the safety codes for the transport of dangerous goods (RID/ADR). Specifically, the concentration of gas in the air was measured under various practical conditions while tank vehicles were being loaded with flammable gases or liquids. These spot-test data were supplemented by systematic investigations at a road tanker placed in our test field. With respect to non-electrical ignition sources, a closer investigation of the effect of hot surfaces was carried out. With regard to improving the current regulations, the results of our investigation show that it would be reasonable to implement a stronger differentiation of the characteristics of the dangerous goods (gaseous/liquid, flashpoint) on the one hand and of the techniques applied (loading with and without vapour-balancing system) on the other hand. Conclusions for the further development of the current international regulations are proposed.

Explosion protection for vehicles intended for the transport of flammable gases and liquids-An investigation into technical and operational basics

International Nuclear Information System (INIS)

Foerster, Hans; Guenther, Werner

2009-01-01

In Europe, the transport of flammable gases and liquids in tanks has been impacted by new developments: for example, the introduction of the vapour-balancing technique on a broad scale and the steady increase in the application of electronic components with their own power sources; furthermore, new regulatory policies like the ATEX Directives are being enforced in the European Union. With this background in mind, the present investigation aims to provide a basis for future developments of the relevant explosion protection regulations in the safety codes for the transport of dangerous goods (RID/ADR). Specifically, the concentration of gas in the air was measured under various practical conditions while tank vehicles were being loaded with flammable gases or liquids. These spot-test data were supplemented by systematic investigations at a road tanker placed in our test field. With respect to non-electrical ignition sources, a closer investigation of the effect of hot surfaces was carried out. With regard to improving the current regulations, the results of our investigation show that it would be reasonable to implement a stronger differentiation of the characteristics of the dangerous goods (gaseous/liquid, flashpoint) on the one hand and of the techniques applied (loading with and without vapour-balancing system) on the other hand. Conclusions for the further development of the current international regulations are proposed.

Engineering design and exergy analyses for combustion gas turbine based power generation system

International Nuclear Information System (INIS)

Sue, D.-C.; Chuang, C.-C.

2004-01-01

This paper presents the engineering design and theoretical exergetic analyses of the plant for combustion gas turbine based power generation systems. Exergy analysis is performed based on the first and second laws of thermodynamics for power generation systems. The results show the exergy analyses for a steam cycle system predict the plant efficiency more precisely. The plant efficiency for partial load operation is lower than full load operation. Increasing the pinch points will decrease the combined cycle plant efficiency. The engineering design is based on inlet air-cooling and natural gas preheating for increasing the net power output and efficiency. To evaluate the energy utilization, one combined cycle unit and one cogeneration system, consisting of gas turbine generators, heat recovery steam generators, one steam turbine generator with steam extracted for process have been analyzed. The analytical results are used for engineering design and component selection

First Study of Helium Gas Purification System as Primary Coolant of Co-Generation Reactor

International Nuclear Information System (INIS)

Piping Supriatna

2009-01-01

The technological progress of NPP Generation-I on 1950’s, Generation-II, Generation-III recently on going, and Generation-IV which will be implemented on next year 2025, concept of nuclear power technology implementation not only for generate electrical energy, but also for other application which called cogeneration reactor. Commonly the type of this reactor is High Temperature Reactor (HTR), which have other capabilities like Hydrogen production, desalination, Enhanced Oil Recovery (EOR), etc. The cogeneration reactor (HTR) produce thermal output higher than commonly Nuclear Power Plant, and need special Heat Exchanger with helium gas as coolant. In order to preserve heat transfer with high efficiency, constant purity of the gas must be maintained as well as possible, especially contamination from its impurities. In this report has been done study for design concept of HTR primary coolant gas purification system, including methodology by sampling He gas from Primary Coolant and purification by using Physical Helium Splitting Membrane. The examination has been designed in physical simulator by using heater as reactor core. The result of study show that the of Primary Coolant Gas Purification System is enable to be implemented on cogeneration reactor. (author)

49 CFR 173.2 - Hazardous materials classes and index to hazard class definitions.

Science.gov (United States)

2010-10-01

....50 1 1.6 Extremely insensitive detonating substances 173.50 2 2.1 Flammable gas 173.115 2 2.2 Non-flammable compressed gas 173.115 2 2.3 Poisonous gas 173.115 3 Flammable and combustible liquid 173.120 4 4.1 Flammable solid 173.124 4 4.2 Spontaneously combustible material 173.124 4 4.3 Dangerous when wet...

49 CFR 172.400 - General labeling requirements.

Science.gov (United States)

2010-10-01

... 172.411 1.6 EXPLOSIVES 1.6 172.411 2.1 FLAMMABLE GAS 172.417 2.2 NONFLAMMABLE GAS 172.415 2.3 POISON GAS 172.416 3 (flammable liquid) Combustible liquid FLAMMABLE LIQUID (none) 172.419 4.1 FLAMMABLE... B) POISON 172.430 6.2 INFECTIOUS SUBSTANCE 1 172.432 7 (see § 172.403) RADIOACTIVE WHITE-I 172.436 7...

Gas Supply, Pricing Mechanism and the Economics of Power Generation in China

Directory of Open Access Journals (Sweden)

Yuanxin Liu

2018-04-01

Full Text Available During the “13th Five-Year Plan” period, green energy is the top priority for China. China has realized that natural gas, as a low-carbon energy source, fits with the nation’s energy demand and will play a critical role in the energy transition, but the actual industry development is slower than expected. By analyzing the major gas corporations around the world, the paper finds that the key factors of the sector are supply and price of the energy resource. A comprehensive analysis on domestic and foreign imported gas reveals a trend of oversupply in China in the future. Given the critical import dependence, China has introduced a series of gas price reforms since 2013, which have led to negative impacts on important gas consumption sectors including power generation. With the levelized cost of electricity (LCOE model, we find that under the prevailing gas supply structure and price level, the economy of utility gas power generation will remain unprofitable, while combined cooling heating and power (CCHP is only commercially feasible in coastal developed regions. If continuing, such a trend will not only bring forth disastrous consequences to gas power industry, but also damage the upstream gas industry, more importantly, impede the energy transition. We conclude the paper with policy implications on pricing mechanism reform, developing domestic unconventional gas and the R&D of gas turbine.

Prediction of Non-Equilibrium Kinetics of Fuel-Rich Kerosene/LOX Combustion in Gas Generator

International Nuclear Information System (INIS)

Yu, Jung Min; Lee, Chang Jin

2007-01-01

Gas generator is the device to produce high enthalpy gases needed to drive turbo-pump system in liquid rocket engine. And, the combustion temperature in gas generator should be controlled below around 1,000K to avoid any possible thermal damages to turbine blade by using either fuel rich combustion or oxidizer rich combustion. Thus, nonequilibrium chemical reaction dominates in fuel-rich combustion of gas generator. Meanwhile, kerosene is a compounded fuel with various types of hydrocarbon elements and difficult to model the chemical kinetics. This study focuses on the prediction of the non-equilibrium reaction of fuel rich kerosene/LOX combustion with detailed kinetics developed by Dagaut using PSR (Perfectly Stirred Reactor) assumption. In Dagaut's surrogate model for kerosene, chemical kinetics of kerosene consists of 1,592 reaction steps with 207 chemical species. Also, droplet evaporation time is taken into account in the PSR calculation by changing the residence time of droplet in the gas generator. Frenklach's soot model was implemented along with detailed kinetics to calculate the gas properties of fuel rich combustion efflux. The results could provide very reliable and accurate numbers in the prediction of combustion gas temperature,species fraction and material properties

Techno-economic assessment and policy of gas power generation considering the role of multiple stakeholders in China

International Nuclear Information System (INIS)

Dong Jun; Zhang Xu; Xu Xiaolin

2012-01-01

In accordance with the energy planning in China, within the “Twelfth Five-Year” period (2011–2015), the proportion of natural gas among primary energy consumption is expected to increase from the current 4% to 8%. In 2015, about 17 natural gas pipelines will be completed. This paper reviews the current situation of gas power generation, analyzes the main opportunities and obstacles of gas power generation development in China, and conducts a techno-economic assessment of the natural gas power generation, taking into account the role and the interaction of the multiple stakeholders in the natural gas industry chain. Taking a power plant fueled with the natural gas transported by the second West-to-East Pipeline as an example, it is found that the on-grid power price fluctuates upward with the rise of gas price and downward with the increase of annual utilization hours, and the influences of tax policies on the on-grid power price prove to be highly significant. As the analysis and calculation indicate, the environmental benefits of natural gas power generation ought to be strongly emphasized, compared with coal-fired power generation. Finally, this paper puts forward specific policy recommendations, from the perspectives of electricity price, gas price, tax, power grid dispatching, etc. - Highlights: ► Presents the opportunities and obstacles of gas power generation development in China. ► Analyzes the interactions of multiple stakeholders in the natural gas industry chain. ► Conducts a techno-economic assessment on the natural gas power generation. ► Discusses the responsibilities and risks of multiple stakeholders. ► Puts forward policy recommendations, from electricity price, gas price, tax, etc.

Fleet Composition of Rail Tank Cars That Transport Flammable Liquids: 2013-2016

Science.gov (United States)

2017-09-05

Section 7308 of the Fixing America's Surface Transportation Act (FAST Act; P. L. 114-94; December 4, 2015) requires the U.S. Department of Transportation (DOT) to assemble and collect data on rail tank cars transporting Class 3 flammable liquids (box...

Power generation potential using landfill gas from Ontario municipal solid waste landfills. Appendix B2

International Nuclear Information System (INIS)

Anon.

1993-01-01

Twenty-six landfill sites have been identified in Ontario with potential gas production rates suitable for recovery and use in power plant applications. If 70% of the gas naturally generated from these sites was collected and utilized, ca 88 MW could be produced in 1991 (declining to 74 MW by 2001) from the gas generated. Assuming the current average generation rate of one tonne per capita, an estimated nine million tonnes of municipal refuse is produced annually in Ontario, and landfilling is expected to continue to play a major role. It is suggested that the level of gas generation identified for the year 1991 will be sustainable given that as old landfills are spent, new ones are built. The accuracy of the prediction depends largely on future government policies regarding incineration, the effects of present waste reduction programs, and approval of new landfill sites. Due to the combined costs of the gas collection system, auxiliary equipment, and gas processing system, installed cost of a landfill-gas fired power plant is high relative to that of conventional natural gas-fired plants. For landfills presently without a gas collection system, the high initial capital investment for gas field test programs and for the installation of a collection system is a barrier that deters municipalities from tapping this energy potential. 2 figs., 3 tabs

Gas jet structure influence on high harmonic generation

OpenAIRE

Grant-Jacob, James; Mills, Benjamin; Butcher, Thomas J.; Chapman, Richard T.; Brocklesby, William S.; Frey, Jeremy G.

2011-01-01

Gas jets used as sources for high harmonic generation (HHG) have a complex three-dimensional density and velocity profile. This paper describes how the profile influences the generation of extreme-UV light. As the position of the laser focus is varied along the jet flow axis, we show that the intensity of the output radiation varies by approximately three times, with the highest flux being observed when the laser is focused into the Mach disc. The work demonstrated here will aid in the optimi...

Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.

Energy Technology Data Exchange (ETDEWEB)

Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

2011-09-01

Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

Development of Large-Format Lithium-Ion Cells with Silicon Anode and Low Flammable Electrolyte

Science.gov (United States)

Wu, James J.; Hernandez-Lugo, D. M.; Smart, M. C.; Ratnakumar, B. V.; Miller, T. B.; Lvovich, V. F.; Lytle, J. K.

2014-01-01

NASA is developing safe, high energy and high capacity lithium-ion cell designs and batteries for future missions under NASAs Advanced Space Power System (ASPS) project. Advanced cell components, such as high specific capacity silicon anodes and low-flammable electrolytes have been developed for improving the cell specific energy and enhancing safety. To advance the technology readiness level, we have developed large-format flight-type hermetically sealed battery cells by incorporating high capacity silicon anodes, commercially available lithium nickel, cobalt, aluminum oxide (NCA) cathodes, and low-flammable electrolytes. In this report, we will present the performance results of these various battery cells. In addition, we will also discuss the post-test cell analysis results as well.

Counter-Rotatable Fan Gas Turbine Engine with Axial Flow Positive Displacement Worm Gas Generator

Science.gov (United States)

Giffin, Rollin George (Inventor); Murrow, Kurt David (Inventor); Fakunle, Oladapo (Inventor)

2014-01-01

A counter-rotatable fan turbine engine includes a counter-rotatable fan section, a worm gas generator, and a low pressure turbine to power the counter-rotatable fan section. The low pressure turbine maybe counter-rotatable or have a single direction of rotation in which case it powers the counter-rotatable fan section through a gearbox. The gas generator has inner and outer bodies having offset inner and outer axes extending through first, second, and third sections of a core assembly. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes and extending radially outwardly and inwardly respectively. The helical blades have first, second, and third twist slopes in the first, second, and third sections respectively. A combustor section extends through at least a portion of the second section.

Power import or domestic power generation using gas?

International Nuclear Information System (INIS)

Saettler, M.; Bohnenschaefer, W.; Schlesinger, M.

2001-01-01

This report for the Swiss Federal Office of Energy (SFOE) presents expert opinion on the question of how Switzerland could meet its demands for power in the future. The results of the analysis of two options - the import of electrical power or its generation using natural-gas-fired power stations - made in the light of gas market liberalisation are presented. These include the assessment of the use of 'GuD' (combined gas and steam-turbine) power stations in the 100 MW e l to 400 MW e l class regarding their cost, their emissions and primary energy consumption. The authors discuss the assessments from the political and economic points of view. An appendix supplies characteristic data for 'GuD' power stations and an example of a model calculation for a 400 MW e l 'GuD' power station

Natural gas power generation: interruptible gas distribution network regulation; Geracao termoeletrica a gas natural: regulacao do segmento interruptivel de distribuicao de gas canalizado

Energy Technology Data Exchange (ETDEWEB)

Paula, Claudio Paiva de; Kann, Zevi [Agencia Reguladora de Saneamento e Energia do Estado de Sao Paulo (ARSESP), SP (Brazil)

2008-07-01

The paper relates studies regarding the natural gas distribution network interruptible branch. This new service can be appropriate for thermal power generation on flexible dispatch mode, as 'take or pay' contracts surplus jobs. The paper indicates no regulatory restraints in an interruptible network implantation. The final conclusion is that interruptible contracts can be an improvement on the distribution business and certainly can accommodate a suitable demand and supply volumes in the long-term gas market balance. (author)

Considerations for reduction of gas generation in a low-level radioactive waste repository

International Nuclear Information System (INIS)

Cho, Chan Hee; Son, Jung Kwon; Lee, Myung Chan; Song, Myung Jae

1997-01-01

In a low-level radioactive waste repository, H 2 , CO 2 , and CH 4 will be generated principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. The metal corrosion model incorporates a three-stage process encompassing aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. A prediction is made for gas concentrations and generation rates over an assessment period of ten thousand years in a radioactive waste repository. The results suggest that H 2 is the principal gas generated within the radioactive waste cavern. The generation rates of CO 2 and CH 4 are likely to be insignificant by comparison with H 2 . Therefore, an effective way to decrease gas generation in a radioactive waste repository seems to be to reduce metal content since the generation rate of H 2 is most sensitive to the concentration of steel

Accounting for fuel price risk when comparing renewable togas-fired generation: the role of forward natural gas prices

Energy Technology Data Exchange (ETDEWEB)

Bolinger, Mark; Wiser, Ryan; Golove, William

2004-07-17

Unlike natural gas-fired generation, renewable generation (e.g., from wind, solar, and geothermal power) is largely immune to fuel price risk. If ratepayers are rational and value long-term price stability, then--contrary to common practice--any comparison of the levelized cost of renewable to gas-fired generation should be based on a hedged gas price input, rather than an uncertain gas price forecast. This paper compares natural gas prices that can be locked in through futures, swaps, and physical supply contracts to contemporaneous long-term forecasts of spot gas prices. We find that from 2000-2003, forward gas prices for terms of 2-10 years have been considerably higher than most contemporaneous long-term gas price forecasts. This difference is striking, and implies that comparisons between renewable and gas-fired generation based on these forecasts over this period have arguably yielded results that are biased in favor of gas-fired generation.

Automation of steam generator services at public service electric & gas

Energy Technology Data Exchange (ETDEWEB)

Cruickshank, H.; Wray, J.; Scull, D. [Public Service Electric & Gas, Hancock`s Bridge, NJ (United States)

1995-03-01

Public Service Electric & Gas takes an aggressive approach to pursuing new exposure reduction techniques. Evaluation of historic outage exposure shows that over the last eight refueling outages, primary steam generator work has averaged sixty-six (66) person-rem, or, approximately tewenty-five percent (25%) of the general outage exposure at Salem Station. This maintenance evolution represents the largest percentage of exposure for any single activity. Because of this, primary steam generator work represents an excellent opportunity for the development of significant exposure reduction techniques. A study of primary steam generator maintenance activities demonstrated that seventy-five percent (75%) of radiation exposure was due to work activities of the primary steam generator platform, and that development of automated methods for performing these activities was worth pursuing. Existing robotics systems were examined and it was found that a new approach would have to be developed. This resulted in a joint research and development project between Westinghouse and Public Service Electric & Gas to develop an automated system of accomplishing the Health Physics functions on the primary steam generator platform. R.O.M.M.R.S. (Remotely Operated Managed Maintenance Robotics System) was the result of this venture.

Mechanistic analysis of double-shell tank gas release

Energy Technology Data Exchange (ETDEWEB)

Allemann, R.T.; Antoniak, Z.I.; Friley, J.R.; Haines, C.E.; Liljegren, L.M.; Somasundaram, S.

1991-12-01

Pacific Northwest Laboratory (PNL) is studying possible mechanisms and fluid dynamics contributing to the periodic release of gases from the double-shell waste storage tanks at Hanford. This study is being conducted for Westinghouse Hanford Company (WHC), a contractor for the US Department of Energy (DOE). This interim report discusses the work done through November 1990. Safe management of the wastes at Hanford depends on an understanding of the chemical and physical mechanisms that take place in the waste tanks. An example of the need to understand these mechanisms is tank 101-SY. The waste in this tank is generating and periodically releasing potentially flammable gases into the tank vent system according to observations of the tank. How these gases are generated and become trapped, the causes of periodic release, and the mechanism of the release are not known in detail. In order to develop a safe mitigation strategy, possible physical mechanisms for the periodic release of flammable gases need to be understood.

Moisture effects on greenhouse gases generation in nitrifying gas-phase compost biofilters.

Science.gov (United States)

Maia, Guilherme D N; Day, George B; Gates, Richard S; Taraba, Joseph L; Coyne, Mark S

2012-06-01

Gas-phase compost biofilters are extensively used in concentrated animal feeding operations to remove odors and, in some cases, ammonia from air sources. The expected biochemical pathway for these predominantly aerobic systems is nitrification. However, non-uniform media with low oxygen levels can shift biofilter microbial pathways to denitrification, a source of greenhouse gases. Several factors contribute to the formation of anoxic/anaerobic zones: media aging, media and particle structure, air velocity distribution, compaction, biofilm thickness, and moisture content (MC) distribution. The present work studies the effects of media moisture conditions on ammonia (NH(3)) removal and greenhouse gas generation (nitrous oxide, N(2)O and methane, CH(4)) for gas-phase compost biofilters subject to a 100-day controlled drying process. Continuous recordings were made for the three gases and water vapor (2.21-h sampling cycle, each cycle consisted of three gas species, and water vapor, for a total of 10,050 data points). Media moisture conditions were classified into three corresponding media drying rate (DR) stages: Constant DR (wetter media), falling DR, and stable-dry system. The first-half of the constant DR period (0-750 h; MC=65-52%, w.b.) facilitated high NH(3) removal rates, but higher N(2)O generation and no CH(4) generation. At the drier stages of the constant DR (750-950 h; MC=52-48%, w.b.) NH(3) removal remained high but N(2)O net generation decreased to near zero. In the falling DR stage (1200-1480 h; MC=44-13%) N(2)O generation decreased, CH(4) increased, and NH(3) was no longer removed. No ammonia removal or greenhouse gas generation was observed in the stable-dry system (1500-2500 h; MC=13%). These results indicate that media should remain toward the drier region of the constant DR (in close proximity to the falling DR stage; MC=50%, approx.), to maintain high levels of NH(3) removal, reduced levels of N(2)O generation, and nullify levels of CH(4

Flammability of self-extinguishing kenaf/ABS nanoclays composite for aircraft secondary structure

Science.gov (United States)

Karunakaran, S.; Majid, D. L.; Mohd Tawil, M. L.

2016-10-01

This study investigates the flammability properties of kenaf fiber reinforced acrylonitrile butadiene styrene (ABS) with nanoclays composites. Natural fiber is one of the potential materials to be used with thermoplastic as a composite due to its attractive properties such as lightweight and strong. In this paper, flammability properties of this material are evaluated through Underwriters Laboratory 94 Horizontal Burning (UL94 HB), which has been conducted for both controlled and uncontrolled conditions, smoke density and limiting oxygen index tests (LOI). These flammability tests are in compliance with the Federal Aviation Regulation (FAR) requirement. The results from UL94 HB and smoke density tests show that the presence of nanoclays with effective composition of kenaf fiber reinforced ABS has enhanced the burning characteristics of the material by hindering propagation of flame spread over the surface of the material through char formation. Consequently, this decreases the burning rate and produces low amount of smoke during burning. On contrary, through LOI test, this material requires less oxygen to burn when exposed to fire, which hinders the enhancement of burning characteristics. This is due to burning mechanism exhibited by nanoclays that catalyzes barrier formation and flame propagation rate over the surface of the biocomposite material. Overall, these experimental results suggest that this biocomposite material is capable of self-extinguishing and possesses effective fire extinction. The observed novel synergism from the result obtained is promising to be implemented in secondary structures of aircraft with significant benefits such as cost-effective, lightweight and biodegradable self-extinguishing biocomposite.

Gas generation and release from the VLJ repository

International Nuclear Information System (INIS)

Vieno, T.; Valkiainen, M.

1992-01-01

The VLJ repository is an underground disposal facility located at the Olkiluoto nuclear power plant site on the west coast of Finland. The repository will house low (LLW) and intermediate level radioactive wastes (MLW) from the TVO I and TVO II BWR's and the spent fuel interim store at Olkiluoto. The disposal rooms have been excavated at a depth of 60... 100 meters in the crystalline bedrock. They consist of two rock silos - one for the LLW and the other for MLW. Low level waste is usually packed in steel drums and steel boxes. Medium level wastes consists of bituminized resins in steel drums. Wastes packages are emplaced in concrete boxes before transportation into the repository. Low level wastes are emplaced in the shotcreted rock silo where no backfilling will used. For medium level wastes, a separate silo of reinforced concrete has been constructed inside the rock silo. No backfilling will be used inside the concrete silo and an opening will be made in the lid of the concrete silo for gas release. The microbial degradation of low level wastes is the principle gas generation process in the repository. The gas transport though the bedrock covering the repository is evaluated with the help of ground water flow study. It is recommended that the shotcrete lining on the ceiling of the repository cavern is partly removed before the final sealing of the repository. Provided that dissipation of gases from the disposal cavern into the rock can been assured, the overall effects of gas generation on the long-term safety of the repository are insignificant. 10 refs., 6 figs

Gas-cooled reactor application for a university campus

International Nuclear Information System (INIS)

Colak, Ue.; Kadiroghlu, O.K.; Soekmen, C.N.; Schmitt, H.

1991-01-01

Large urban areas with unfavourable topographic and meteorological conditions suffer severe air pollution during the winter months. Use of low grade lignites, imported higher quality coal or imported fuel oil are the sources of air pollution in the form of sulphur dioxide, fly ash and soot. Large housing complexes or old and historical locations within the city are in need of pollution free centralized district heating systems. Natural gas imported from the Soviet Union is a solution for this problem. Lack of gas distribution network for high pressure gas within the city is the main bottle-neck for the heating systems utilizing natural gas. Concern of the safety of flammable high pressure gas circulating within the city is another drawback for the natural gas heating systems. Nuclear district heating is an environmentally viable option worth looking into it. Localized urban nuclear heating is an interesting solution for large urban areas with old and historical character. The results of a feasibility study on the HGR application for the Hacettepe University presented here, summarizes the concept of gas-cooled heating reactors specially designed for urban centers. The inherently safe characteristics of the pebble bed heating reactor makes localized urban nuclear heating a viable alternative to other heat sources. An economical analysis of various heat sources with equal power levels is done for the Beytepe campus of Hacettepe University in Ankara. Under special boundary conditions, the price for heat generation can be much lower for nuclear heating with GHR 20 than for hard coal or fuel oil. It is also possible that if the price escalation rate for natural gas exceeds 3%, then nuclear heating with GHR can be more competitive. It is concluded that the nuclear heating of Beytepe campus with a GHR 20 is feasible and economical. (author) 3 figs., 5 refs

High methane natural gas/air explosion characteristics in confined vessel.

Science.gov (United States)

Tang, Chenglong; Zhang, Shuang; Si, Zhanbo; Huang, Zuohua; Zhang, Kongming; Jin, Zebing

2014-08-15

The explosion characteristics of high methane fraction natural gas were investigated in a constant volume combustion vessel at different initial conditions. Results show that with the increase of initial pressure, the peak explosion pressure, the maximum rate of pressure rise increase due to a higher amount (mass) of flammable mixture, which delivers an increased amount of heat. The increased total flame duration and flame development time result as a consequence of the higher amount of flammable mixture. With the increase of the initial temperature, the peak explosion pressures decrease, but the pressure increase during combustion is accelerated, which indicates a faster flame speed and heat release rate. The maximum value of the explosion pressure, the maximum rate of pressure rise, the minimum total combustion duration and the minimum flame development time is observed when the equivalence ratio of the mixture is 1.1. Additionally, for higher methane fraction natural gas, the explosion pressure and the maximum rate of pressure rise are slightly decreased, while the combustion duration is postponed. The combustion phasing is empirically correlated with the experimental parameters with good fitting performance. Furthermore, the addition of dilute gas significantly reduces the explosion pressure, the maximum rate of pressure rise and postpones the flame development and this flame retarding effect of carbon dioxide is stronger than that of nitrogen. Copyright © 2014 Elsevier B.V. All rights reserved.

Electricity generation from landfill gas: a commercial view revisited

International Nuclear Information System (INIS)

Limbrick, A.J.

1992-01-01

Wapsey's Wood power station has been generating electricity from landfill gas since 1987. Despite a good technical track record, the project did not secure a fair price for the electricity it sold until it was included in the 1991 Non-Fossil Fuel Obligation (NFFO). The NFFO has served to bring forward approximately 560 MW of renewable energy generating capacity, of which 15 per cent is fuelled by landfill gas. However, case histories such as that of Wapsey's Wood highlight the weaknesses of the current arrangements. To secure the continued steady growth of commercially robust renewable energy projects, there is a need to boost the business confidence of potential developers. The paper proposes two ways to remove the present uncertainty: simplify the application procedures, and remove the December 1998 expiry date that currently applies to power purchase agreements under the NFFO. (author)

METHODOLOGY AND CALCULATIONS FOR THE ASSIGNMENT OF WASTE GROUPS FOR THE LARGE UNDERGROUND WASTE STORAGE TANKS AT THE HANFORD SITE

Energy Technology Data Exchange (ETDEWEB)

WEBER RA

2009-01-16

The Hanford Site contains 177 large underground radioactive waste storage tanks (28 double-shell tanks and 149 single-shell tanks). These tanks are categorized into one of three waste groups (A, B, and C) based on their waste and tank characteristics. These waste group assignments reflect a tank's propensity to retain a significant volume of flammable gases and the potential of the waste to release retained gas by a buoyant displacement gas release event. Assignments of waste groups to the 177 double-shell tanks and single-shell tanks, as reported in this document, are based on a Monte Carlo analysis of three criteria. The first criterion is the headspace flammable gas concentration following release of retained gas. This criterion determines whether the tank contains sufficient retained gas such that the well-mixed headspace flammable gas concentration would reach 100% of the lower flammability limit if the entire tank's retained gas were released. If the volume of retained gas is not sufficient to reach 100% of the lower flammability limit, then flammable conditions cannot be reached and the tank is classified as a waste group C tank independent of the method the gas is released. The second criterion is the energy ratio and considers whether there is sufficient supernatant on top of the saturated solids such that gas-bearing solids have the potential energy required to break up the material and release gas. Tanks that are not waste group C tanks and that have an energy ratio < 3.0 do not have sufficient potential energy to break up material and release gas and are assigned to waste group B. These tanks are considered to represent a potential induced flammable gas release hazard, but no spontaneous buoyant displacement flammable gas release hazard. Tanks that are not waste group C tanks and have an energy ratio {ge} 3.0, but that pass the third criterion (buoyancy ratio < 1.0, see below) are also assigned to waste group B. Even though the designation as

METHODOLOGY AND CALCULATIONS FOR THE ASSIGNMENT OF WASTE GROUPS FOR THE LARGE UNDERGROUND WASTE STORAGE TANKS AT THE HANFORD SITE

Energy Technology Data Exchange (ETDEWEB)

FOWLER KD

2007-12-27

This document categorizes each of the large waste storage tanks into one of several categories based on each tank's waste characteristics. These waste group assignments reflect a tank's propensity to retain a significant volume of flammable gases and the potential of the waste to release retained gas by a buoyant displacement event. Revision 7 is the annual update of the calculations of the flammable gas Waste Groups for DSTs and SSTs. The Hanford Site contains 177 large underground radioactive waste storage tanks (28 double-shell tanks and 149 single-shell tanks). These tanks are categorized into one of three waste groups (A, B, and C) based on their waste and tank characteristics. These waste group assignments reflect a tank's propensity to retain a significant volume of flammable gases and the potential of the waste to release retained gas by a buoyant displacement gas release event. Assignments of waste groups to the 177 double-shell tanks and single-shell tanks, as reported in this document, are based on a Monte Carlo analysis of three criteria. The first criterion is the headspace flammable gas concentration following release of retained gas. This criterion determines whether the tank contains sufficient retained gas such that the well-mixed headspace flammable gas concentration would reach 100% of the lower flammability limit if the entire tank's retained gas were released. If the volume of retained gas is not sufficient to reach 100% of the lower flammability limit, then flammable conditions cannot be reached and the tank is classified as a waste group C tank independent of the method the gas is released. The second criterion is the energy ratio and considers whether there is sufficient supernatant on top of the saturated solids such that gas-bearing solids have the potential energy required to break up the material and release gas. Tanks that are not waste group C tanks and that have an energy ratio < 3.0 do not have sufficient

Utilization of hydrogen gas production for electricity generation in ...

African Journals Online (AJOL)

Utilization of hydrogen gas production for electricity generation in fuel cell by Enterobacter aerogenes ADH 43 with many kinds of carbon sources in batch stirred tank reactor. MA Rachman, LD Eniya, Y Liasari, MM Nasef, A Ahmad, H Saidi ...

The behavior, quantity, and location of undissolved gas in Tank 241-SY-101

Energy Technology Data Exchange (ETDEWEB)

Brewster, M.E.; Gallagher, N.B.; Hudson, J.D.; Stewart, C.W.

1995-10-01

Mitigation of episodic flammable gas releases from Hanford Waste Tank 241-SY-101 was accomplished in July 1993 with the installation of a mixer pump that prevents gas retention. But is has not been possible until recently to measure the effects of mixing on the waste or how much gas remains and where it is located. Direct measurements of the void fraction and rheology of the mixed waste by the void fraction instrument (VFI) and ball rheometer along with previous data provide estimates of the location, quantity, and behavior of undissolved gas in the tank. This report documents the compilation and integration of the information that enables this understanding.

Progress Toward a Microfabricated Gas Turbine Generator for Soldier Portable Power Applications

National Research Council Canada - National Science Library

Jacobson, S. A; Das, S; Savoulides, N; Steyn, J. L; Lang, J; Li, H. Q; Livermore, C; Schmidt, M. A; Teo, C. J; Umans, S. D; Epstein, A. H; Arnold, D. P; Park, J-W; Zana, I; Allen, M. G

2004-01-01

Microelectromechanical systems (MEMS) turbocharger and electric generator devices have been fabricated and tested as part of a program at MIT to develop a microfabricated gas turbine generator for portable power applications...

Ensuring Reliable Natural Gas-Fired Generation with Fuel Contracts and Storage - DOE/NETL-2017/1816

Energy Technology Data Exchange (ETDEWEB)

Myles, Paul T. [National Energy Technology Lab. (NETL), Albany, OR (United States); Labarbara, Kirk A. [National Energy Technology Lab. (NETL), Albany, OR (United States); Logan, Cecilia Elise [National Energy Technology Lab. (NETL), Albany, OR (United States)

2017-11-17

This report finds that natural gas-fired power plants purchase fuel both on the spot market and through firm supply contracts; there do not appear to be clear drivers propelling power plants toward one or the other type. Most natural gas-fired power generators are located near major natural gas transmission pipelines, and most natural gas contracts are currently procured on the spot market. Although there is some regional variation in the type of contract used, a strong regional pattern does not emerge. Whether gas prices are higher with spot or firm contracts varies by both region and year. Natural gas prices that push the generators higher in the supply curve would make them less likely to dispatch. Most of the natural gas generators discussed in this report would be unlikely to enter firm contracts if the agreed price would decrease their dispatch frequency. The price points at which these generators would be unlikely to enter a firm contract depends upon the region that the generator is in, and how dependent that region is on natural gas. The Electric Reliability Council of Texas (ERCOT) is more dependent on natural gas than either Eastern Interconnection or Western Interconnection. This report shows that above-ground storage is prohibitively expensive with respect to providing storage for an extended operational fuel reserve comparable to the amount of on-site fuel storage used for coal-fired plants. Further, both pressurized and atmospheric tanks require a significant amount of land for storage, even to support one day’s operation at full output. Underground storage offers the only viable option for 30-day operational storage of natural gas, and that is limited by the location of suitable geologic formations and depleted fields.

Advanced On Board Inert Gas Generation System (OBBIGS), Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Valcor Engineering Corporation proposes to develop an advanced On Board Inert Gas Generation System, OBIGGS, for aircraft fuel tank inerting to prevent hazardous...

Recovery Act: Brea California Combined Cycle Electric Generating Plant Fueled by Waste Landfill Gas

Energy Technology Data Exchange (ETDEWEB)

Galowitz, Stephen

2012-12-31

The primary objective of the Project was to maximize the productive use of the substantial quantities of waste landfill gas generated and collected at the Olinda Landfill near Brea, California. An extensive analysis was conducted and it was determined that utilization of the waste gas for power generation in a combustion turbine combined cycle facility was the highest and best use. The resulting Project reflected a cost effective balance of the following specific sub-objectives: • Meeting the environmental and regulatory requirements, particularly the compliance obligations imposed on the landfill to collect, process and destroy landfill gas • Utilizing proven and reliable technology and equipment • Maximizing electrical efficiency • Maximizing electric generating capacity, consistent with the anticipated quantities of landfill gas generated and collected at the Olinda Landfill • Maximizing equipment uptime • Minimizing water consumption • Minimizing post-combustion emissions • The Project produced and will produce a myriad of beneficial impacts. o The Project created 360 FTE construction and manufacturing jobs and 15 FTE permanent jobs associated with the operation and maintenance of the plant and equipment. o By combining state-of-the-art gas clean up systems with post combustion emissions control systems, the Project established new national standards for best available control technology (BACT). o The Project will annually produce 280,320 MWh’s of clean energy o By destroying the methane in the landfill gas, the Project will generate CO2 equivalent reductions of 164,938 tons annually. The completed facility produces 27.4 MWnet and operates 24 hours a day, seven days a week.

Generation of oxy-hydrogen gas and its effect on performance of spark ignition engine

Science.gov (United States)

Patil, N. N.; Chavan, C. B.; More, A. S.; Baskar, P.

2017-11-01

Considering the current scenario of petroleum fuels, it has been observed that, they will last for few years from now. On the other hand, the ever increasing cost of a gasoline fuels and their related adverse effects on environment caught the attention of researchers to find a supplementary source. For commercial fuels, supplementary source is not about replacing the entire fuel, instead enhancing efficiency by simply making use of it in lesser amount. From the recent research that has been carried out, focus on the use of Hydrogen rich gas as a supplementary source of fuel has increased. But the problem related to the storage of hydrogen gas confines the application of pure hydrogen in petrol engine. Using oxy-hydrogen gas (HHO) generator the difficulties of storing the hydrogen have overcome up to a certain limit. The present study highlights on performance evaluation of conventional petrol engine by using HHO gas as a supplementary fuel. HHO gas was generated from the electrolysis of water. KOH solution of 3 Molar concentration was used which act as a catalyst and accelerates the rate of generation of HHO gas. Quantity of gas to be supplied to the engine was controlled by varying amount of current. It was observed that, engine performance was improved on the introduction of HHO gas.

Fires in the Cenozoic: a late flowering of flammable ecosystems

OpenAIRE

Bond, William J.

2015-01-01

Modern flammable ecosystems include tropical and subtropical savannas, steppe grasslands, boreal forests, and temperate sclerophyll shrublands. Despite the apparent fiery nature of much contemporary vegetation, terrestrial fossil evidence would suggest we live in a time of low fire activity relative to the deep past. The inertinite content of coal, fossil charcoal, is strikingly low from the Eocene to the Pleistocene and no charcoalified mesofossils have been reported for the Cenozoic. Marine...

Status and integration of the gas generation studies performed for the Hydrogen Safety Program

International Nuclear Information System (INIS)

Pederson, L.R.; Strachan, D.M.

1993-02-01

Waste in Tank 241-SY-101 on the Hanford Site generates and periodically releases hydrogen, nitrous oxide, and nitrogen gases. Studies have been conducted at several laboratories to determine the chemical mechanisms for the gas generation and release. Results from these studies are presented and integrated in an attempt to describe current understanding of the physical properties of the waste and the mechanisms of gas generation and retention. Existing tank data are consistent with the interpretation that gases are uniformly generated in the tank, released continuously from the convecting layer, and stored in the nonconvecting layer. Tank temperature measurements suggest that the waste consists of ''gobs'' of material that reach neutral buoyancy at different times. The activation energy of the rate limiting step of the gas generating process was calculated to be about 7 kJ/mol but measured in the laboratory at 80 to 100 kJ/mol. Based on observed temperature changes in the tank the activation energy is probably not higher than about 20 kJ/mol. Several simulated waste compositions have been devised for use in laboratory studies in the place of actual waste from Tank 241-SY-101. Data from these studies can be used to predict how the actual waste might behave when heated or diluted. Density evaluations do not confirm that heating waste at the bottom of the tank would induce circulation within the waste; however, heating may release gas bubbles by dissolving the solids to which the bubbles adhere. Gas generation studies on simulated wastes indicated that nitrous oxide and hydrogen yields are not particularly coupled. Solubility studies of nitrous oxide, the most soluble of the principal gaseous products, indicate it is unlikely that dissolved gases contribute substantially to the quantity of gas released during periodic events

Using Probability of Exceedance to Compare the Resource Risk of Renewable and Gas-Fired Generation

Energy Technology Data Exchange (ETDEWEB)

Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-08-01

Of the myriad risks surrounding long-term investments in power plants, resource risk is one of the most difficult to mitigate, and is also perhaps the risk that most-clearly distinguishes renewable generation from natural gas-fired generation. For renewable generators like wind and solar projects, resource risk manifests as a quantity risk—i.e., the risk that the quantity of wind and insolation will be less than expected.i For gas-fired generators (i.e., a combined-cycle gas turbine or “CCGT”), resource risk manifests primarily as a price risk—i.e., the risk that natural gas will cost more than expected. Most often, resource risk—and natural gas price risk in particular—falls disproportionately on utility ratepayers, who are typically not well-equipped to manage this risk. As such, it is incumbent upon utilities, regulators, and policymakers to ensure that resource risk is taken into consideration when making or approving resource decisions, or enacting policies that influence the development of the electricity sector more broadly.

Gas generation in SFL 3-5 and effects on radionuclide release

International Nuclear Information System (INIS)

Skagius, K.; Lindgren, M.; Pers, K.

1999-12-01

A deep repository, SFL 3-5, is presently planned for disposing of long-lived low- and intermediate-level waste. In this study the amounts of gas that can be generated in the waste packages and in the vaults are estimated. The potential gas pressure build-up, the displacement of contaminated water and the consequences on radionuclide release from the engineered barriers in the repository are also addressed. The study is focussed on the repository design and waste inventory that was defined for the prestudy of SFL 3-5. Since the reporting of the prestudy the design of the repository has been modified and the waste inventory has been updated and a preliminary safety assessment of the repository has been carried out based on the new design and updated waste inventory. The implications on gas generation and release of these modifications in design and waste inventory are briefly addressed in this study

Gas generation in SFL 3-5 and effects on radionuclide release

Energy Technology Data Exchange (ETDEWEB)

Skagius, K.; Lindgren, M.; Pers, K. [Kemakta Konsult AB, Stockholm (Sweden)

1999-12-01

A deep repository, SFL 3-5, is presently planned for disposing of long-lived low- and intermediate-level waste. In this study the amounts of gas that can be generated in the waste packages and in the vaults are estimated. The potential gas pressure build-up, the displacement of contaminated water and the consequences on radionuclide release from the engineered barriers in the repository are also addressed. The study is focussed on the repository design and waste inventory that was defined for the prestudy of SFL 3-5. Since the reporting of the prestudy the design of the repository has been modified and the waste inventory has been updated and a preliminary safety assessment of the repository has been carried outbased on the new design and updated waste inventory. The implications on gas generation and release of these modifications in design and waste inventory are briefly addressed in this study.

Apples with apples: accounting for fuel price risk in comparisons of gas-fired and renewable generation

Energy Technology Data Exchange (ETDEWEB)

Bolinger, Mark; Wiser, Ryan

2003-12-18

For better or worse, natural gas has become the fuel of choice for new power plants being built across the United States. According to the US Energy Information Administration (EIA), natural gas combined-cycle and combustion turbine power plants accounted for 96% of the total generating capacity added in the US between 1999 and 2002--138 GW out of a total of 144 GW. Looking ahead, the EIA expects that gas-fired technology will account for 61% of the 355 GW new generating capacity projected to come on-line in the US up to 2025, increasing the nationwide market share of gas-fired generation from 18% in 2002 to 22% in 2025. While the data are specific to the US, natural gas-fired generation is making similar advances in other countries as well. Regardless of the explanation for (or interpretation of) the empirical findings, however, the basic implications remain the same: one should not blindly rely on gas price forecasts when comparing fixed-price renewable with variable-price gas-fired generation contracts. If there is a cost to hedging, gas price forecasts do not capture and account for it. Alternatively, if the forecasts are at risk of being biased or out of tune with the market, then one certainly would not want to use them as the basis for resource comparisons or investment decisions if a more certain source of data (forwards) existed. Accordingly, assuming that long-term price stability is valued, the most appropriate way to compare the levelized cost of these resources in both cases would be to use forward natural gas price data--i.e. prices that can be locked in to create price certainty--as opposed to uncertain natural gas price forecasts. This article suggests that had utilities and analysts in the US done so over the sample period from November 2000 to November 2003, they would have found gas-fired generation to be at least 0.3-0.6 cents/kWh more expensive (on a levelized cost basis) than otherwise thought. With some renewable resources, in particular wind

An Earth-Based Equivalent Low Stretch Apparatus to Assess Material Flammability for Microgravity & Extraterrestrial Fire-Safety Applications

Science.gov (United States)

Olson, S. L.; Beeson, H.; Haas, J.

2001-01-01

One of the performance goals for NASA's enterprise of Human Exploration and Development of Space (HEDS) is to develop methods, data bases, and validating tests for material flammability characterization, hazard reduction, and fire detection/suppression strategies for spacecraft and extraterrestrial habitats. This work addresses these needs by applying the fundamental knowledge gained from low stretch experiments to the development of a normal gravity low stretch material flammability test method. The concept of the apparatus being developed uses the low stretch geometry to simulate the conditions of the extraterrestrial environment through proper scaling of the sample dimensions to reduce the buoyant stretch in normal gravity. The apparatus uses controlled forced-air flow to augment the low stretch to levels which simulate Lunar or Martian gravity levels. In addition, the effect of imposed radiant heat flux on material flammability can be studied with the cone heater. After breadboard testing, the apparatus will be integrated into NASA's White Sands Test Facility's Atmosphere-Controlled Cone Calorimeter for evaluation as a new materials screening test method.

Competition between coal and gas for large scale power generation

International Nuclear Information System (INIS)

Howieson, B.

1997-01-01

The relative competitiveness of coal- and gas-fired generation will be affected by distinctive country and market factors as well as site specific considerations, regarding such factors as environment, market structure and economics (such as fuel and plant costs). National and international politics have an impact on all three factors and any decision on the development of generation plant must take into account both current and future political climates. An analysis suggests that, at the present time, upgrading existing coal stations is attractive compared with new combined cycle gas turbines (CCGTs). However, this conclusion is highly dependent on the site specific nature of existing plant and the anticipated future environmental regime. Increased environmental pressure, particularly in the area of CO 2 emissions, would result in CCGTs being the first choice plant option. (R.P.)

Study of gas generation in drum L/ILW packages using hermetic containers

International Nuclear Information System (INIS)

Molnar, M.; Palcsu, L.; Svingor, E.; Futo, I.; Major, Z.; Veres, M.

2005-01-01

Complete text of publication follows. During the storage of low and intermediate level radioactive waste (L/ILW) significant quantities of gas may be produced. It is likely that a small proportion of the generated gas will be radioactive as a result of the incorporation of the isotopes 3 H and 14 C that are present within the waste. To obtain reliable estimates of the quantities and rates of the gas production in L/ILWa series of measurements was carried out of waste packages produced and temporarily stored at the site of Paks Nuclear Power Plant (NPP). Ten drums filled with selected original L/ILW were placed into hermetic containers equipped with sampling valves for repeated sampling. These hermetic containers were stored at the same site where the L/ILW is stored primarily in the Paks NPP. The pressure and the temperature of the headspace gas in the containers were monitored continuously. Qualitative gas component analyses of headspace gases of drums and their containers were executed by quadrupole mass spectrometer. The gas generation rate in the stored L/ILW was calculated by the measured state parameters and the composition variation of the gas in the closed containers. Stable isotope measurements were executed from the CO 2 , CH 4 and N 2 fractions by stable isotope ratio mass spectrometer. Helium measurements were done by noble gas mass spectrometer. The tritium content of the vapour, H 2 and CH 4 fractions was measured by a low background liquid scintillation counter. 14 C content of the CO 2 and CH 4 fractions was measured by a low background gas proportional counter system (ATOMKI). Our results showed that the main generated gases in L/ILW are carbon dioxide, methane, hydrogen and nitrogen. The typical rates were 0.05-0.2 normal litre gas/day for CO 2 and CH 4 generation, and less than 0.02 normal litre gas/day for H 2 . Because of the typical vanishing of the O 2 from the headspace gases no explosive gas mixture was indicated in the L/ILW drums during

PW-6ES gas turbine generator for Maglev linear motor car. Yamanashi rinia jikkensen daiichi hensei sharyo tosaiyo PW-6ES gas tabin hatsuden sochi

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, T [JR Railway Technical Research Inst., Tokyo (Japan); Nakamura, S [Ebara Corp., Tokyo (Japan)

1994-06-10

A power generator is developed to be used as the auxiliary power source for the first carriage at the levitation type railway Yamanashi linear experimental line. The gas turbine generator is installed to supply power to the electric equipment on the carriage, and the power generating conditions are transmitted to the ground commanding room via on-board central control system for centralized controlling. An aircraft diversion type ST6 gas turbine and a high frequency light weight generator are combined for the gas turbine generator developed this time. Single reduction planetary gear is employed for the reduction gear which connects the two units directly, the gas turbine being connected to one side and the generator to the other side with no coupling. The output of the generator is 350kW, AC 455V, and 400Hz, and power is supplied to the electric devices on the carriage after having been converted to DC 600V. Aluminium is used to reduce the weights of the soundproof enclosure and exhaust dust shell plate. 1 fig., 1 tab.

Numerical Study of the Working Process in the Reducing Gas Generator of the Upper Stage Oxygen - Methane Engine

Directory of Open Access Journals (Sweden)

D. M. Yagodnikov

2015-01-01

Full Text Available This article deals with the problems of creating a reducing gas generator of the liquid rocket engine (LRE of upper stage using advanced fuel components, namely oxygen + liquid natural gas. Relevance of the work is justified by the need to create and develop of environmentally friendly missile systems for space applications using methane-based fuel (liquid natural gas. As compared to the currently used unsymmetrical dimethyl-hydrazine and kerosene, this fuel is environmentally safe, passive to corrosion, has better cooling properties and high energy characteristics in the re-generatively cooled chambers, as well as is advantageous for LRE of multiple start and use.The purpose of this work is a mathematical modeling, calculation of the working process efficiency, as well as study of gas-dynamic structure of the flow in the gas generator flow path. The object of study is the upper stage LRE gas generator, which uses the reducing scheme on the liquid propellants: oxygen + liquid methane. Research methods are based on numerical simulation.Computational studies allowed us to receive the velocity, temperatures, and concentrations of reactants and combustion products in the longitudinal section of gas generator. Analysis of the gas-dynamic structure of flow shows a complete equalization of the velocity field by 2/3 of the gas generator length. Thus, the same distance is not enough to equalize the temperature distribution of the gasification products and their concentrations in radius. Increasing the total excess oxidant ratio from 0.15 to 0.25 leads to a greater spread of the parameters at the exit of the gas generator by ~ 13 ÷ 17%. As a recommendation to reduce the size of the working area, is proposed a dual-zone gas generator-mixing scheme with fuel separately supplied to the first and second zones.

Advanced Combustion Systems for Next Generation Gas Turbines

Energy Technology Data Exchange (ETDEWEB)

Joel Haynes; Jonathan Janssen; Craig Russell; Marcus Huffman

2006-01-01

Next generation turbine power plants will require high efficiency gas turbines with higher pressure ratios and turbine inlet temperatures than currently available. These increases in gas turbine cycle conditions will tend to increase NOx emissions. As the desire for higher efficiency drives pressure ratios and turbine inlet temperatures ever higher, gas turbines equipped with both lean premixed combustors and selective catalytic reduction after treatment eventually will be unable to meet the new emission goals of sub-3 ppm NOx. New gas turbine combustors are needed with lower emissions than the current state-of-the-art lean premixed combustors. In this program an advanced combustion system for the next generation of gas turbines is being developed with the goal of reducing combustor NOx emissions by 50% below the state-of-the-art. Dry Low NOx (DLN) technology is the current leader in NOx emission technology, guaranteeing 9 ppm NOx emissions for heavy duty F class gas turbines. This development program is directed at exploring advanced concepts which hold promise for meeting the low emissions targets. The trapped vortex combustor is an advanced concept in combustor design. It has been studied widely for aircraft engine applications because it has demonstrated the ability to maintain a stable flame over a wide range of fuel flow rates. Additionally, it has shown significantly lower NOx emission than a typical aircraft engine combustor and with low CO at the same time. The rapid CO burnout and low NOx production of this combustor made it a strong candidate for investigation. Incremental improvements to the DLN technology have not brought the dramatic improvements that are targeted in this program. A revolutionary combustor design is being explored because it captures many of the critical features needed to significantly reduce emissions. Experimental measurements of the combustor performance at atmospheric conditions were completed in the first phase of the program

Two generators to produce SI-traceable reference gas mixtures for reactive compounds at atmospheric levels

Science.gov (United States)

Pascale, C.; Guillevic, M.; Ackermann, A.; Leuenberger, D.; Niederhauser, B.

2017-12-01

To answer the needs of air quality and climate monitoring networks, two new gas generators were developed and manufactured at METAS in order to dynamically generate SI-traceable reference gas mixtures for reactive compounds at atmospheric concentrations. The technical features of the transportable generators allow for the realization of such gas standards for reactive compounds (e.g. NO2, volatile organic compounds) in the nmol · mol-1 range (ReGaS2), and fluorinated gases in the pmol ṡ mol-1 range (ReGaS3). The generation method is based on permeation and dynamic dilution. The transportable generators have multiple individual permeation chambers allowing for the generation of mixtures containing up to five different compounds. This mixture is then diluted using mass flow controllers, thus making the production process adaptable to generate the required amount of substance fraction. All parts of ReGaS2 in contact with the gas mixture are coated to reduce adsorption/desorption processes. Each input parameter required to calculate the generated amount of substance fraction is calibrated with SI-primary standards. The stability and reproducibility of the generated amount of substance fractions were tested with NO2 for ReGaS2 and HFC-125 for ReGaS3. They demonstrate stability over 1-4 d better than 0.4% and 0.8%, respectively, and reproducibility better than 0.7% and 1%, respectively. Finally, the relative expanded uncertainty of the generated amount of substance fraction is smaller than 3% with the major contributions coming from the uncertainty of the permeation rate and/or of the purity of the matrix gas. These relative expanded uncertainties meet then the needs of the data quality objectives fixed by the World Meteorological Organization.

Use of gas for new generating capacity - The customer's view

International Nuclear Information System (INIS)

Linderman, C.W.

1992-01-01

This paper reviews the future gas demand for electric power generation in the US. It shows substantial growth along the eastern seaboard which will require pipeline capacity additions in order to serve the load. Many of the existing gas-fired plants fuel will switch to a commodity which will probably not comply with many of the new emissions requirements and that the alternate fuel for new units will be distillate oil. The demand for gas appears to be at the upper end of some of the gas supply scenarios. In serving the industry, there are a number of considerations that the gas transportation sector of the gas industry must identify. Pipelines will be dealing with a new group of organizations which they may or may not be familiar. Some of the real time operational differences that are seen at this point, especially dealing with load response and reliability, are crucial to a successful interface. This paper concludes that the previous levels of interaction must be replaced by a greater level of coordination than both industries have had previously

Functional design criteria for the retained gas sampler system

International Nuclear Information System (INIS)

Wootan, D.W.

1995-01-01

A Retained Gas Sampler System (RGSS) is being developed to capture and analyze waste samples from Hanford Flammable Gas Watch List Tanks to determine both the quantity and composition of gases retained in the waste. The RGSS consists of three main components: the Sampler, Extractor, and Extruder. This report describes the functional criteria for the design of the RGSS components. The RGSS Sampler is based on the WHC Universal Sampler design with modifications to eliminate gas leakage. The primary function of the Sampler is to capture a representative waste sample from a tank and transport the sample with minimal loss of gas content from the tank to the laboratory. The function of the Extruder is to transfer the waste sample from the Sampler to the Extractor. The function of the Extractor is to separate the gases from the liquids and solids, measure the relative volume of gas to determine the void fraction, and remove and analyze the gas constituents

Mechanisms of gas generation from simulated SY tank farm wastes: FY 1995 progress report

International Nuclear Information System (INIS)

Barefield, E.K.; Boatright, D.; Deshpande, A.; Doctorovich, F.; Liotta, C.L.; Neumann, H.M.; Seymore, S.

1996-07-01

The objective of this work is to develop a better understanding of the mechanism of formation of flammable gases in the thermal decomposition of metal complexants such as HEDTA and sodium glycolate in simulated SY tank farm waste mixtures. This report summarizes the results of work done at the Georgia Institute of Technology in fiscal year 1995. Topics discussed are (1) long-term studies of the decomposition of HEDTA in simulated waste mixtures under an argon atmosphere at 90 and 120 degrees C, including time profiles for disappearance of HEDTA and appearance of products and the quantitative analysis of the kinetic behavior; (2) considerations of hydroxylamine as an intermediate in the production of nitrogen containing gases by HEDTA decomposition; (3) some thoughts on the revision of the global mechanism for thermal decomposition of HEDTA under argon; (4) preliminary long-term studies of the decomposition of HEDTA in simulated waste under an oxygen atmosphere at 120 degrees C; (5) estimation of the amount of NH 3 in the gas phase above HEDTA reaction mixtures; and (6) further, examination of the interaction of aluminum with nitrite ion using 27 Al NMR spectroscopy. Section 2 of this report describes the work conducted over the last three years at GIT. Section 3 contains a discussion of the kinetic behavior of HEDTA under argon; Section 4 discusses the role of hydroxylamine. Thermal decomposition of HEDTA to ED3A is the subject of Section 5, and decomposition of HEDTA in simulated waste mixtures under oxygen is covered in Section 6. In Section 7 we estimate ammonia in the gas phase; the role of aluminum is discussed in Section 8

Long-term congestion management by investment in gas-turbine generators : a cost-benefit analysis

International Nuclear Information System (INIS)

Tuan, L.A.; Bhattacharya, K.

2007-01-01

Load management is one of the most important tasks in the operation of an electric power system. Transmission congestion occurs whenever the grid has one or more violations of the physical, operation, or policy constraints under which it normally operates. In a deregulated electricity market, the independent system operator (ISO) must ensure that contracted power transactions are carried out reliably. Several schemes of congestion management run the risk of increasing electricity prices due to the market power of local generators in congested areas. An alternative is to manage congestion through the installation of reserve gas turbine generators which can be brought online to the system within a short time. The use of gas turbines at different buses in the system can enhance the system in ways of transmission relief during emergency events. This paper proposed a framework for the evaluation of long-term investment by the ISO on gas-turbine generators as a tool for providing transmission congestion relief in the dispatch stage based on cost-benefit analysis. The objective of the framework is to optimally decide the locations and sizes of the generators at different buses in the network in order to minimize the total cost of investment of gas turbines and to minimize total system congestion. A bus-wise cost-benefit analysis was carried out by solving the DC optimal power flow (dc-OPF) model. The CIGRE 32-Bus system was used for the case study. It was shown that network overloading can be significantly reduced with the support of gas turbines at selected buses. The long-term decision of the investment on gas-turbine would depend on the opportunity cost of the gas-turbine with respect to the congestion problem. The gas turbines could also reduce the amount of unserved energy during peak load conditions. 11 refs., 4 tabs., 3 figs

Study on economic potential of nuclear-gas combined cycle power generation in Chinese market

International Nuclear Information System (INIS)

Zhou Zhiwei; Bian Zhiqiang; Yang Mengjia

2004-01-01

Facing the challenges of separation of electric power plant and grid, and the deregulation of Chinese electricity supplying market in near future, nuclear power plants mainly operated as based load at the present regulated market should look for new operation mode. The economics of electric generation with nuclear-natural gas combined cycle is studied based on current conditions of natural gas and nuclear power plants in China. The results indicate that the technology development of nuclear-natural gas combined cycle for power generation is of potential prospects in Chinese electric market. (authors)

Layout of an internally heated gas generator for the steam gasification of coal

International Nuclear Information System (INIS)

Feistel, P.P.; Duerrfeld, R.; Heck, K.H. van; Juentgen, H.

1975-01-01

Industrial-scale steam gasification of coal using heat from high temperature reactors requires research and development on allothermal gas generators. Bergbau-Forschung GmbH, Essen, does theoretical and experimental work in this field. The experiments deal with reaction kinetics, heat transfer and material tests. Their significance for the layout of a full-scale gas generator is shown. Including material specifications, the feasibility of a gasifier, characterized by a fluid bed volume of 318 m 3 and a heat transferring area of 4000 m 2 , results. The data, now available, are used to determine the gasification throughput from the heat balance, i.e. the equality of heat consumed and heat transferred. Throughputs of about 50 t/hr of coal are possible for a single gas generator, the helium outlet temperature of the HTR being 950 0 C/ Bergbau-Forschung has commissioned a medium-scale pilot plant (200 kg/hr). (Auth.)

The effects of introducing natural gas in the Canary Islands for electricity generation

International Nuclear Information System (INIS)

Ramos-Real, Francisco Javier; Moreno-Piquero, Juan Carlos; Ramos-Henriquez, Jose Manuel

2007-01-01

This study analyses the economic effects of introducing natural gas in the Canary Islands to generate electricity in combined cycle gas turbine (CCGT) plants. To this end we will evaluate how this measure contributes to achieving the objectives of the islands' energy policy and we calculate the cost of generating a kWh from this technology. For this calculation we obtain the net present value (NPV) of the total production costs during the economic lifetime of the plant so as to subsequently find the unitary cost per kWh generated. The result obtained indicates that the kWh cost is some 25% lower than the cost of using petroleum derivatives. Additionally, if we consider the positive effect of CO 2 emissions reductions, the cost is 41% lower. The introduction of natural gas will also be a decisive factor in complying with Kyoto requirements and in diversifying supply sources in the Canaries

Microbial Gas Generation Under Expected Waste Isolation Pilot Plant Repository Conditions: Final Report

International Nuclear Information System (INIS)

Gillow, J.B.; Francis, A.

2011-01-01

Gas generation from the microbial degradation of the organic constituents of transuranic (TRU) waste under conditions expected in the Waste Isolation Pilot Plant (WIPP) was investigated. The biodegradation of mixed cellulosic materials and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, hypalon, leaded hypalon, and neoprene) was examined. We evaluated the effects of environmental variables such as initial atmosphere (air or nitrogen), water content (humid (∼70% relative humidity, RH) and brine inundated), and nutrient amendments (nitogen phosphate, yeast extract, and excess nitrate) on microbial gas generation. Total gas production was determined by pressure measurement and carbon dioxide (CO 2 ) and methane (CH 4 ) were analyzed by gas chromatography; cellulose degradation products in solution were analyzed by high-performance liquid chromatography. Microbial populations in the samples were determined by direct microscopy and molecular analysis. The results of this work are summarized.

Roadmapping the Resolution of Gas Generation Issues in Packages Containing Radioactive Waste/Materials - A Status Report

International Nuclear Information System (INIS)

Luke, D.E.; Hamp, S.

2002-01-01

Gas generation issues, particularly hydrogen, have been an area of concern for the transport and storage of radioactive materials and waste in the Department of Energy (DOE) Complex. Potentially combustible gases can be generated through a variety of reactions, including chemical reactions and radiolytic decomposition of hydrogen-containing material. Since transportation regulations prohibit shipment of explosives and radioactive materials together, it was decided that hydrogen generation was a problem that warranted the execution of a high-level roadmapping effort. This paper discusses the major gas generation issues within the DOE Complex and the research that has been and is being conducted by the transuranic (TRU) waste, nuclear materials, and spent nuclear fuels (SNF) programs within DOE's Environmental Management (EM) organizations to address gas generation concerns. This paper presents a ''program level'' roadmap that links technology development to program needs and identifies the probability of success in an effort to understand the programmatic risk associated with the issue of gas generation. This paper also presents the status of the roadmap and follow-up activities

30 CFR 35.22 - Test to determine effect of evaporation on flammability.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Test to determine effect of evaporation on... § 35.22 Test to determine effect of evaporation on flammability. (a) Purpose. The purpose of this test shall be to determine the effect of evaporation on the reduction of fire resistance of a hydraulic fluid...

Natural gas power generation in Brazil: New window of opportunity?

International Nuclear Information System (INIS)

Gorini de Oliveira, Ricardo; Moraes Marreco, Juliana de

2006-01-01

This survey analyses the need as well as the attractiveness of private investment in natural gas thermal power generation under the Brazilian new power sector reform. Providing a scenario analysis from 2004 to 2014, this paper focuses on the investor perspective, and concludes that investments in natural gas thermal power plants in Brazil are not feasible, without financial subsidies stimulating investors. The more wary of risk both government and society are, and the more averse to risk the investor is, the higher the probability of higher capacity payment to provide incentives to investors. The alternative would be a lower capacity payment combined with higher thermal power tariffs; meaning that generators would receive much more payment when operating, despite assuming higher risks. Additionally, the improvement in safety supply cost is estimated and a sensibility analysis on the actual variables is performed

Maximum Potential Hydrogen Gas Retention in the sRF Resin Ion Exchange Column for the LAWPS Process

Energy Technology Data Exchange (ETDEWEB)

Gauglitz, Phillip A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wells, Beric E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bottenus, Courtney LH [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schonewill, Philip P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)