WorldWideScience

Sample records for dissolved gas monitoring

  1. Millstone 3 condensate dissolved gas monitoring

    International Nuclear Information System (INIS)

    Burns, T.F.; Grondahl, E.E.; Snyder, D.T.

    1988-01-01

    Condensate dissolved oxygen problems at Millstone Point Unit 3 (MP3) were investigated using the Dissolved Gas Monitoring System developed by Radiological and Chemical Technology, Inc. under EPRI sponsorship. Argon was injected into the turbine exhaust basket tips to perform a dissolved gas transport analysis and determine steam jet air ejector gas removal efficiency. The operating configuration of the steam jet air ejector system was varied to determine the effect on gas removal efficiency. Following circulating water chlorination, the gas removal efficiency was determined to evaluate the effect of condenser tube fouling on steam jet air ejector performance

  2. Total Dissolved Gas Monitoring in Chum Salmon Spawning Gravels Below Bonneville Dam

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Geist, David R.; Panther, Jennifer L.; Dawley, Earl

    2007-01-30

    At the request of the U.S. Army Corps of Engineers (Portland District), Pacific Northwest National Laboratory (PNNL) conducted research to determine whether total dissolved gas concentrations are elevated in chum salmon redds during spring spill operations at Bonneville Dam. The study involved monitoring the total dissolved gas levels at egg pocket depth and in the river at two chum salmon spawning locations downstream from Bonneville Dam. Dissolved atmospheric gas supersaturation generated by spill from Bonneville Dam may diminish survival of chum (Oncorhynchus keta) salmon when sac fry are still present in the gravel downstream from Bonneville Dam. However, no previous work has been conducted to determine whether total dissolved gas (TDG) levels are elevated during spring spill operations within incubation habitats. The guidance used by hydropower system managers to provide protection for pre-emergent chum salmon fry has been to limit TDG to 105% after allowing for depth compensation. A previous literature review completed in early 2006 shows that TDG levels as low as 103% have been documented to cause mortality in sac fry. Our study measured TDG in the incubation environment to evaluate whether these levels were exceeded during spring spill operations. Total dissolved gas levels were measured within chum salmon spawning areas near Ives Island and Multnomah Falls on the Columbia River. Water quality sensors screened at egg pocket depth and to the river were installed at both sites. At each location, we also measured dissolved oxygen, temperature, specific conductance, and water depth to assist with the interpretation of TDG results. Total dissolved gas was depth-compensated to determine when levels were high enough to potentially affect sac fry. This report provides detailed descriptions of the two study sites downstream of Bonneville Dam, as well as the equipment and procedures employed to monitor the TDG levels at the study sites. Results of the monitoring at

  3. AN APPLICATION OF FLOW INJECTION ANALYSIS WITH GAS DIFFUSION AND SPECTROPHOTOMETRIC DETECTION FOR THE MONITORING OF DISSOLVED SULPHIDE CONCENTRATION IN ENVIRONMENTAL SAMPLES

    Directory of Open Access Journals (Sweden)

    Malwina Cykowska

    2014-10-01

    Full Text Available The monitoring of the concentration of sulphide is very important from the environment point of view because of high toxicity of hydrogen sulphide. What is more hydrogen sulphide is an important pollution indicator. In many cases the determination of sulphide is very difficult due to complicated matrix of some environmental samples, which causes that most analytical methods cannot be used. Flow injection analysis allows to avoid matrix problem what makes it suitable for a wide range of applications in analytical laboratories. In this paper determination of dissolved sulphide in environmental samples by gas-diffusion flow injection analysis with spectrophotometric detection was presented. Used gas-diffusion separation ensures the elimination of interferences caused by sample matrix and gives the ability of determination of sulphides in coloured and turbid samples. Studies to optimize the measurement conditions and to determine the value of the validation parameters (e.g. limit of detection, limit of quantification, precision, accuracy were carried out. Obtained results confirm the usefulness of the method for monitoring the concentration of dissolved sulphides in water and waste water. Full automation and work in a closed system greatly reduces time of analysis, minimizes consumption of sample and reagents and increases safety of analyst’s work.

  4. Recovery of krypton-85 from dissolver off-gas streams

    International Nuclear Information System (INIS)

    Law, J.P.; Lamb, K.M.

    1988-01-01

    The Rare Gas Plant at the Idaho Chemical Processing Plant Recovers fission product krypton and xenon from dissolver off gas streams. Recently the system was upgraded to allow processing of hydrogen rich dissolver off-gas streams. A trickle bed hydrogen recombiner was installed and tested. The Rare Gas Plant can now safely process gas streams containing up to 80% hydrogen

  5. Measuring and understanding total dissolved gas pressure in groundwater

    Science.gov (United States)

    Ryan, C.; Roy, J. W.; Randell, J.; Castellon, L.

    2009-05-01

    Since dissolved gases are important to a number of aspects of groundwater (e.g. age dating, active or passive bioremediation, greenhouse gas fluxes, understanding biogeochemical processes involving gases, assessing potential impacts of coal bed methane activities), accurate concentration measurements, and understanding of their subsurface behaviour are important. Researchers have recently begun using total dissolved gas pressure (TGP) sensor measurements, more commonly applied for surface water monitoring, in concert with gas composition analyses to estimate more accurate groundwater gas concentrations in wells. We have used hydraulic packers to isolate the well screens where TDP is being measured, and pump tests to indicate that in-well degassing may reduce TDG below background groundwater levels. Thus, in gas-charged groundwater zones, TGPs can be considerably underestimated in the absence of pumping or screen isolation. We have also observed transient decreased TGPs during pumping that are thought to result from ebullition induced when the water table or water level in the well is lowered below a critical hydrostatic pressure.

  6. Total dissolved gas, barometric pressure, and water temperature data, lower Columbia River, Oregon and Washington, 1996

    Science.gov (United States)

    Tanner, Dwight Q.; Harrison, Howard E.; McKenzie, Stuart W.

    1996-01-01

    Increased levels of total dissolved gas pressure can cause gas-bubble trauma in fish downstream from dams on the Columbia River. In cooperation with the U.S. Army Corps of Engineers, the U.S. Geological Survey collected data on total dissolved gas pressure, barometric pressure, water temperature, and dissolved oxygen pressure at 11 stations on the lower Columbia River from the John Day forebay (river mile 215.6) to Wauna Mill (river mile 41.9) from March to September 1996. Methods of data collection, review, and processing are described in this report. Summaries of daily minimum, maximum, and mean hourly values are presented for total dissolved gas pressure, barometric pressure, and water temperature. Hourly values for these parameters are presented graphically. Dissolved oxygen data are not presented in this report because the quality-control data show that the data have poor precision and high bias. Suggested changes to monitoring procedures for future studies include (1) improved calibration procedures for total dissolved gas and dissolved oxygen to better define accuracy at elevated levels of supersaturation and (2) equipping dissolved oxygen sensors with stirrers because river velocities at the shoreline monitoring stations probably cannot maintain an adequate flow of water across the membrane surface of the dissolved oxygen sensor.

  7. Dissolved oxygen mapping: A powerful tool for site assessments and ground water monitoring

    International Nuclear Information System (INIS)

    Newman, W.A.; Kimball, G.

    1992-01-01

    Dissolved oxygen concentration profiles often provide an excellent indication of the natural biological activity of microorganisms in ground water. The analysis of dissolved oxygen in ground water also provides a rapid, inexpensive method for determining the areal extent of contaminant plumes containing aerobically degraded compounds such as petroleum hydrocarbons. Indigenous hydrocarbon degrading organisms are present at most petroleum product spills giving this technique an almost universal application for dissolved hydrocarbons in ground water. Data from several sites will be presented to demonstrate the relationship between oxygen and dissolved contaminant concentrations. The inverse relationship between oxygen concentrations and dissolved contaminants can be used in many ways. During the initial site assessment, rapid on-site testing of ground water can provide real time data to direct drilling by identification of potentially contaminated locations. Several analytical techniques are available that allow field analysis to be performed in less than five minutes. Dissolved oxygen testing also provides an inexpensive way to monitor hydrocarbon migration without expensive gas chromatography. Often a plume of oxygen depleted ground water extends farther downgradient than the dissolved hydrocarbon plume. The depletion of oxygen in a well can provide an early warning system that detects upgradient contamination before the well is impacted by detectable levels of contaminants. Another application is the measurement of the natural degradation potential for aerobic remediation. If an aerobic in-situ remediation is used, dissolved oxygen monitoring provides an inexpensive method to monitor the progress of the remediation

  8. A new device for continuous monitoring the CO2 dissolved in water

    Science.gov (United States)

    de Gregorio, S.; Camarda, M.; Cappuzzo, S.; Giudice, G.; Gurrieri, S.; Longo, M.

    2009-04-01

    The measurements of dissolved CO2 in water are common elements of industrial processes and scientific research. In order to perform gas dissolved measurements is required to separate the dissolved gaseous phase from water. We developed a new device able to separate the gases phase directly in situ and well suitable for continuous measuring the CO2 dissolved in water. The device is made by a probe of a polytetrafluorethylene (PTFE) tube connected to an I.R. spectrophotometer (I.R.) and a pump. The PTFE is a polymeric semi-permeable membrane and allows the permeation of gas in the system. Hence, this part of the device is dipped in water in order to equilibrate the probe headspace with the dissolved gases. The partial pressure of the gas i in the headspace at equilibrium (Pi) follows the Henry's law: Pi=Hi•Ci, where Hi is the Henry's constant and Ci is the dissolved concentration of gas i. After the equilibrium is achieved, the partial pressure of CO2 inside the tube is equal to the partial pressure of dissolved CO2. The concentration of CO2 is measured by the I.R. connected to the tube. The gas is moved from the tube headspace to the I.R. by using the pump. In order to test the device and assess the best operating condition, several experimental were performed in laboratory. All the test were executed in a special apparatus where was feasible to create controlled atmospheres. Afterward the device has been placed in a draining tunnel sited in the Mt. Etna Volcano edifice (Italy). The monitored groundwater intercepts the Pernicana Fault, along which degassing phenomena are often observed. The values recorded by the station result in agreement with monthly directly measurements of dissolved CO2 partial pressure.

  9. Dissolved gas concentrations of the geothermal fluids in Taiwan

    Science.gov (United States)

    Chen, Ai-Ti; Yang, Tsanyao Frank

    2010-05-01

    Taiwan, a geologically active island, is located on the boundary of the Philippine Sea Plate and the Eurasian Plate. High heat flow and geothermal gradient generated by the complex collision and orogeny, warm up the meteoric water and/or the ground water. The heated water becomes geothermal fluids. In previous studies, researchers tried to categorize hot springs based on the appearance, chemical compositions and lithological areas. Because of the chemical inertness, the concentrations and isotopic composition of dissolved noble gases are good indicators of the mantle degassing, geothermal conditions, and so on. In this study, 55 hot springs were collected from different tectonic units. It is the first time to systematically study the hot springs in Taiwan in terms of dissolved gases. Hot spring water is sampled and stored in pre-evacuated glass bottles for analyzing gas compositions. The abundances of noble gases were determined by a quadrupole mass spectrometer based on the isotope dilution technique. Samples with glass vials are introduced to RAD 7 and GC for dissolved Rn and major dissolved gases analyses. Furthermore, helium isotopic ratios and helium-neon ratios are measured on a conventional noble gas mass spectrometer. For hydrochemistry analysis, water samples are analyzed by IC, ICP-MS and titration. We can classify the hot springs samples into three major groups from main anion concentration data; and then, subdivide them into nine minor groups by cation concentration data. Moreover, according to major dissolved gases compositions, three major gas components: CH4, N2 and CO2, are identified. Dissolved noble gases provided more detailed clues about hot springs sources in Taiwan, such as the degree of mixing between meteoric water and deep-source water, which will be further discussed in this study.

  10. Monitoring dissolved radioactive cesium in Abukuma River in Fukushima Prefecture

    International Nuclear Information System (INIS)

    Yasutaka, Tetsuo; Kawabe, Yoshishige; Kurosawa, Akihiko; Komai, Takeshi

    2013-01-01

    Radioactive materials were released into the atmosphere and deposited over wide areas of farmland, forests, and cities; elevated levels of "1"3"1I, "1"3"4Cs, and "1"3"7Cs have been detected in these areas due to the accident at the Tokyo Power Fukushima Daiichi Nuclear Power Plant caused by the April 2011 earthquake and tsunami in eastern Japan. Radioactive Cs deposited on farmland and forests gradually leaches into water bodies such as mountain streams and rivers adsorbed onto particles or in a dissolved state. It is important to calrify the level of dissolved and total radioactive Cs in environmental water for forecasting the of discharge of radioactive Cs from forest and watersheds, assessing on the effect of dissolved and total radioactive Cs on not only irrigation water but also rice and other crops, and evaluating the transport of radioactive Cs from rivers to costal areas. Therefore, it is important to monitor their levels in Fukushima Prefecture over time. In this research, we monitored the levels of dissolved and total radioactive Cs in Abukuma River using a conventional evaporative concentration method. By monitoring the river waters since September 2012, it was estimated that the levels of dissolved radioactive Cs were less than 0.128 Bq/L and those of total radioactive Cs were less than 0.274 Bq/L in the main stream and branches of Abukuma River in the low suspended solid condition. (author)

  11. Measurement of dissolved hydrogen and hydrogen gas transfer in a hydrogen-producing reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shizas, I.; Bagley, D.M. [Toronto Univ., ON (Canada). Dept. of Civil Engineering

    2004-07-01

    This paper presents a simple method to measure dissolved hydrogen concentrations in the laboratory using standard equipment and a series of hydrogen gas transfer tests. The method was validated by measuring hydrogen gas transfer parameters for an anaerobic reactor system that was purged with 10 per cent carbon dioxide and 90 per cent nitrogen using a coarse bubble diffuser stone. Liquid samples from the reactor were injected into vials and hydrogen was allowed to partition between the liquid and gaseous phases. The concentration of dissolved hydrogen was determined by comparing the headspace injections onto a gas chromatograph and a standard curve. The detection limit was 1.0 x 10{sup -5} mol/L of dissolved hydrogen. The gas transfer rate for hydrogen in basal medium and anaerobic digester sludge was used to validate the method. Results were compared with gas transfer models. In addition to monitoring dissolved hydrogen in reactor systems, this method can help improve hydrogen production potential. 1 ref., 4 figs.

  12. Detector module for gas monitor

    International Nuclear Information System (INIS)

    1980-01-01

    The invention relates to radioactive source detector module for use in a gas monitor. It is adapted to contain the source and other detector components to allow sealed coupling of those components with other portions of the gas monitor. It is particularly concerned with the use of radioactive materials used as electron sources in gas monitors. The module is used to detect changes in electron flow caused by partial absorption of the electron capture gas flowing between two electrodes. The assembly includes a gas flow source, a gas receiver and an electronic assembly for receiving a signal from the detector. The radioactive source and electrodes are housed so that they are connected to the gas flow source so as to prevent accidental or undesired disconnection. It is designed so that the detector module may be removed or replaced into the gas monitor assemblies by untrained personnel so as to prevent exposure to the radioactive material. Full details are given. (U.K.)

  13. Experimental study on total dissolved gas supersaturation in water

    Directory of Open Access Journals (Sweden)

    Lu Qu

    2011-12-01

    Full Text Available More and more high dams have been constructed and operated in China. The total dissolved gas (TDG supersaturation caused by dam discharge leads to gas bubble disease or even death of fish. Through a series of experiments, the conditions and requirements of supersaturated TDG generation were examined in this study. The results show that pressure (water depth, aeration, and bubble dissolution time are required for supersaturated TDG generation, and the air-water contact area and turbulence intensity are the main factors that affect the generation rate of supersaturated TDG. The TDG supersaturation levels can be reduced by discharging water to shallow shoals downstream of the dam or using negative pressure pipelines. Furthermore, the TDG supersaturation levels in stilling basins have no direct relationship with those in reservoirs. These results are of great importance for further research on the prediction of supersaturated TDG generation caused by dam discharge and aquatic protection.

  14. PREDICTION OF TOTAL DISSOLVED GAS EXCHANGE AT HYDROPOWER DAMS

    Energy Technology Data Exchange (ETDEWEB)

    Hadjerioua, Boualem [ORNL; Pasha, MD Fayzul K [ORNL; Stewart, Kevin M [ORNL; Bender, Merlynn [Bureau of Reclamation; Schneider, Michael L. [U.S. Army Corps of Engineers

    2012-07-01

    Total dissolved gas (TDG) supersaturation in waters released at hydropower dams can cause gas bubble trauma in fisheries resulting in physical injuries and eyeball protrusion that can lead to mortality. Elevated TDG pressures in hydropower releases are generally caused by the entrainment of air in spillway releases and the subsequent exchange of atmospheric gasses into solution during passage through the stilling basin. The network of dams throughout the Columbia River Basin (CRB) are managed for irrigation, hydropower production, flood control, navigation, and fish passage that frequently result in both voluntary and involuntary spillway releases. These dam operations are constrained by state and federal water quality standards for TDG saturation which balance the benefits of spillway operations designed for Endangered Species Act (ESA)-listed fisheries versus the degradation to water quality as defined by TDG saturation. In the 1970s, the United States Environmental Protection Agency (USEPA), under the federal Clean Water Act (Section 303(d)), established a criterion not to exceed the TDG saturation level of 110% in order to protect freshwater and marine aquatic life. The states of Washington and Oregon have adopted special water quality standards for TDG saturation in the tailrace and forebays of hydropower facilities on the Columbia and Snake Rivers where spillway operations support fish passage objectives. The physical processes that affect TDG exchange at hydropower facilities have been studied throughout the CRB in site-specific studies and routine water quality monitoring programs. These data have been used to quantify the relationship between project operations, structural properties, and TDG exchange. These data have also been used to develop predictive models of TDG exchange to support real-time TDG management decisions. These empirically based predictive models have been developed for specific projects and account for both the fate of spillway and

  15. Gas House Autonomous System Monitoring

    Science.gov (United States)

    Miller, Luke; Edsall, Ashley

    2015-01-01

    Gas House Autonomous System Monitoring (GHASM) will employ Integrated System Health Monitoring (ISHM) of cryogenic fluids in the High Pressure Gas Facility at Stennis Space Center. The preliminary focus of development incorporates the passive monitoring and eventual commanding of the Nitrogen System. ISHM offers generic system awareness, adept at using concepts rather than specific error cases. As an enabler for autonomy, ISHM provides capabilities inclusive of anomaly detection, diagnosis, and abnormality prediction. Advancing ISHM and Autonomous Operation functional capabilities enhances quality of data, optimizes safety, improves cost effectiveness, and has direct benefits to a wide spectrum of aerospace applications.

  16. Separation of krypton from dissolver off-gas of a reprocessing plant using preparative gas chromatography

    International Nuclear Information System (INIS)

    Matoni, M.

    1984-02-01

    Kr-85 can be separated from the pre-purified purge air in the final processing step of the purification phase for dissolver off-gases of a reprocessing plant with the aid of preparative gas chromatography. Activated carbon adsorbers in combination with helium as carrier gas permits maximum gas mixture through-flow. A separation temperature of 30 0 C is considered optimal. An adsorbent volume of 40 dm 3 is necessary for processing the residual gas flow of 2.5 Nm 3 /h; the adsorbent is divided between 2 columns linked in series each of which are 2 m long with an internal diameter of 100 mm. The helium flow required is five times greater than the off-gas flow. The degree of purity for krypton is greater than 90% for a decontamination factor of greater than 1000. (orig./HP) [de

  17. Effect of Dissolved gas on bubble behavior of subcooled boiling in narrow channel

    International Nuclear Information System (INIS)

    Li Shaodan; Tan Sichao; Xu Chao; Gao Puzhen; Xu Jianjun

    2013-01-01

    An experimental investigation was performed to study the effect of dissolved gas on bubble behavior in narrow rectangular channel under subcooled boiling condition. A high-speed digital video camera was applied to capture the dynamics of the bubble with or without dissolved gas in a narrow rectangular channel. It is found that the dissolved gas has great influence on bubble behavior in subcooled boiling condition. The dissolved gas slows down the rate of bubble growth and condensation and makes the variation of the bubble diameter present some oscillation characteristics. This phenomenon was discussed in the view of the vapor evaporation and condensation. The existence of the dissolved gas can facilitate the survival of the bubble and promote the aggregation of bubbles, and enhence heat transfer enhancement in some ways. (authors)

  18. Use of a dissolved-gas measurement system for reducing the dissolved oxygen at St. Lucie Unit 2

    International Nuclear Information System (INIS)

    Snyder, D.T.; Coit, R.L.

    1993-02-01

    When the dissolved oxygen in the condensate at St. Lucie Unit 2 could not be reduced below the administrative limit of 10 ppB, EPRI cooperated with Florida Power and Light to find the cause and develop remedies. Two problems were identified with the assistance of a dissolved gas measurement system (DGMS) that can detect leaks into condensate when used with argon blanketing. Drain piping from the air ejection system had flooded which decreased its performance, and leaks were found at a strainer flange and a couple expansion joints. Initially the dissolved oxygen content was reduced to about 9 ppB; owever, the dissolved oxygen from Condenser A was consistently higher than that from condenser B. Injection of about 0.4 cubic per minute (CFM) of argon above the hotwell considerably improved the ventilation of Condenser A, reducing the dissolved oxygen about 30% to about 6 ppB. The use of nitrogen was equally effective. While inert gas injection is helpful, it may be better to have separate air ejectors for each condenser. Several recommendations for improving oxygen removal are given

  19. Suitability of selected free-gas and dissolved-gas sampling containers for carbon isotopic analysis.

    Science.gov (United States)

    Eby, P; Gibson, J J; Yi, Y

    2015-07-15

    Storage trials were conducted for 2 to 3 months using a hydrocarbon and carbon dioxide gas mixture with known carbon isotopic composition to simulate typical hold times for gas samples prior to isotopic analysis. A range of containers (both pierced and unpierced) was periodically sampled to test for δ(13)C isotopic fractionation. Seventeen containers were tested for free-gas storage (20°C, 1 atm pressure) and 7 containers were tested for dissolved-gas storage, the latter prepared by bubbling free gas through tap water until saturated (20°C, 1 atm) and then preserved to avoid biological activity by acidifying to pH 2 with phosphoric acid and stored in the dark at 5°C. Samples were extracted using valves or by piercing septa, and then introduced into an isotope ratio mass spectrometer for compound-specific δ(13)C measurements. For free gas, stainless steel canisters and crimp-top glass serum bottles with butyl septa were most effective at preventing isotopic fractionation (pierced and unpierced), whereas silicone and PTFE-butyl septa allowed significant isotopic fractionation. FlexFoil and Tedlar bags were found to be effective only for storage of up to 1 month. For dissolved gas, crimp-top glass serum bottles with butyl septa were again effective, whereas silicone and PTFE-butyl were not. FlexFoil bags were reliable for up to 2 months. Our results suggest a range of preferred containers as well as several that did not perform very well for isotopic analysis. Overall, the results help establish better QA/QC procedures to avoid isotopic fractionation when storing environmental gas samples. Recommended containers for air transportation include steel canisters and glass serum bottles with butyl septa (pierced and unpierced). Copyright © 2015 John Wiley & Sons, Ltd.

  20. Subcooled boiling heat transfer correlation to calculate the effects of dissolved gas in a liquid

    International Nuclear Information System (INIS)

    Zarkasi, Amin S.; Chao, W.W.; Kunze, Jay F.

    2004-01-01

    The water coolant in most operating power reactor systems is kept free of dissolved gas, so as to minimize corrosion. However, in most research reactors, which operate at temperatures below 70 deg. C, and between 1 and 5 atm. pressure, the dissolved gas remains present in the water coolant system during operation. This dissolved gas can have a significant effect during accident conditions (i.e. a LOCA), when the fluid quickly reaches boiling, coincident with flow stagnation and subsequent flow reversal. A benchmark experiment was conducted, with an electrically heated, closed loop channel, modeling a research reactor fuel coolant channels (2 mm thick). The results showed 'boiling (bubble) noise' occurring before wall temperatures reached saturation, and a significant increase (up to 50%) in the heat transfer coefficient in the subcooled boiling region when in the presence of dissolved gas, compared to degassed water. Since power reactors do not involve dissolved gas, the RELAP safety analysis code does not include any provisions for the effect of dissolved gas on heat transfer. In this work, the effects of the dissolved gas are evaluated for inclusion in the RELAP code, including provision for initiating 'nucleate boiling' at a lower temperature, and a provision for enhancing the heat transfer coefficient during the subcooled boiling region. Instead of relying on Chen's correlation alone, a modification of the superposition method of Bjorge was adopted. (author)

  1. A Novel Infrared Gas Monitor

    Science.gov (United States)

    Wang, Yingding; Zhong, Hongjie

    2000-03-01

    In the paper a novel non-dispersive infrared(IR) gas monitor is described.It is based on the principle that certain gases absorb IR radiation at specific(and often unique) wavelengths.Conventional devices typically include several primary components:a broadband source, usually an incandescent filament,a rotating chopper shutter,a narrow-band filter,a sample tube and a detector. We have developed a number of IR light emitting diodes(LED) having narrow optical bandwidths and which can be intensity modulated by electrical means,for example InAsSbP(4.2 micron)LED.The IR LED can thus replace the thermal source,narrow-band filter and chopper assembly of the conventional IR gas monitor,yielding a solid state,low- powered,compact and almost maintenance-free instrument with high sensitivity and stability and which free of the effects of mechanical vibration too. The detector used in the IR gas monitor is the solid-state detector,such as PbS,PbSe, InSb,HgCdTe,TGS,LT and PZT detector etc. The different configuration of the IR gas monitor is designed.For example,two-path version for measuring methane concentration by monitoring the 3.31 micron absorption band,it can eliminate the interference effects,such as to compensate for LED intensity changes caused by power and temperature variations,and for signal fluctuations due to changes in detector bias. we also have designed portable single-beam version without the sample tube.Its most primary advantage is very cheap(about cost USD 30 ).It measures carbon dioxide concentration by monitoring the 4.25 micron absorption band.Thought its precisions is low,it is used to control carbon dioxide concentration in the air in the green houses and plastic houses(there are about twenty millon one in the China).Because more carbon dioxide will increase the quanity of vegetable and flower production to a greatextent. It also is used in medical,sanitary and antiepidemic applications,such as hospital, store,hotel,cabin and ballroom etc. Key words

  2. Laser Calorimetry Spectroscopy for ppm-level Dissolved Gas Detection and Analysis.

    Science.gov (United States)

    K S, Nagapriya; Sinha, Shashank; R, Prashanth; Poonacha, Samhitha; Chaudhry, Gunaranjan; Bhattacharya, Anandaroop; Choudhury, Niloy; Mahalik, Saroj; Maity, Sandip

    2017-02-20

    In this paper we report a newly developed technique - laser calorimetry spectroscopy (LCS), which is a combination of laser absorption spectroscopy and calorimetry - for the detection of gases dissolved in liquids. The technique involves determination of concentration of a dissolved gas by irradiating the liquid with light of a wavelength where the gas absorbs, and measuring the temperature change caused by the absorbance. Conventionally, detection of dissolved gases with sufficient sensitivity and specificity was done by first extracting the gases from the liquid and then analyzing the gases using techniques such as gas chromatography. Using LCS, we have been able to detect ppm levels of dissolved gases without extracting them from the liquid. In this paper, we show the detection of dissolved acetylene in transformer oil in the mid infrared (MIR) wavelength (3021 nm) region.

  3. Dissolved stable noble gas measurements from primary water of Paks NPP

    International Nuclear Information System (INIS)

    Palcsu, L.; Molnar, M.; Szanto, Zs.; Svingor, E.; Futo, I.; Pinter, T.

    2001-01-01

    A sampling and measuring method of noble gases from the primary water circuit of a VVER type NPP was developed to provide relevant information about the kilter of heating rods and detailed additional information about some working parameters. The helium concentrations and 3 He/ 4 He ratios was used to estimate the content of tritium and alpha emitting isotopes of the primary water. By argon content measurements the air penetration and the required hydrazine amount for the oxygen absorption could be estimated with high accuracy. Continuous monitoring of the concentration and isotope ratios of Xe and Kr in the dissolved gas is proved to be a good tool for high sensitivity detection of small leakage of fuel elements. In case of block-3 xenon surplus was detected. The results indicate possible leakage of fuel rods.(author)

  4. Total dissolved gas prediction and optimization in RiverWare

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Kevin M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Witt, Adam M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Hadjerioua, Boualem [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Management and operation of dams within the Columbia River Basin (CRB) provides the region with irrigation, hydropower production, flood control, navigation, and fish passage. These various system-wide demands can require unique dam operations that may result in both voluntary and involuntary spill, thereby increasing tailrace levels of total dissolved gas (TDG) which can be fatal to fish. Appropriately managing TDG levels within the context of the systematic demands requires a predictive framework robust enough to capture the operationally related effects on TDG levels. Development of the TDG predictive methodology herein attempts to capture the different modes of hydro operation, thereby making it a viable tool to be used in conjunction with a real-time scheduling model such as RiverWare. The end result of the effort will allow hydro operators to minimize system-wide TDG while meeting hydropower operational targets and constraints. The physical parameters such as spill and hydropower flow proportions, accompanied by the characteristics of the dam such as plant head levels and tailrace depths, are used to develop the empirically-based prediction model. In the broader study, two different models are developed a simplified and comprehensive model. The latter model incorporates more specific bubble physics parameters for the prediction of tailrace TDG levels. The former model is presented herein and utilizes an empirically based approach to predict downstream TDG levels based on local saturation depth, spillway and powerhouse flow proportions, and entrainment effects. Representative data collected from each of the hydro projects is used to calibrate and validate model performance and the accuracy of predicted TDG uptake. ORNL, in conjunction with IIHR - Hydroscience & Engineering, The University of Iowa, carried out model adjustments to adequately capture TDG levels with respect to each plant while maintaining a generalized model configuration. Validation results

  5. Field Monitoring of Landfill Gas

    International Nuclear Information System (INIS)

    Silvola, M.; Priha, E.

    2003-01-01

    The Finnish waste legislation requires monitoring of landfill gases. The main goal of this study is to develop instructions for field monitoring of landfill gases to be utilized by consultants and authorities. In the project it was got acquainted with the field analytical methods of landfill gases and instruments of field measurement. It was done various practical field measurements in several landfills. In the studied landfills were observed methane, carbon dioxide and oxygen concentrations and gas forming inside waste embankment in different seasons. It was measured methane emissions that discharged through a landfill surface by a chamber technique. In addition to this it was studied volatile organic compounds (VOC:s), which were liberated in a landfill. It was also studied methane oxidization in cover layers of a landfill. (orig.)

  6. Effects of Total Dissolved Gas on Chum Salmon Fry Incubating in the Lower Columbia River

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Hand, Kristine D.; Geist, David R.; Murray, Katherine J.; Panther, Jenny; Cullinan, Valerie I.; Dawley, Earl M.; Elston, Ralph A.

    2008-01-30

    This report describes research conducted by Pacific Northwest National Laboratory in FY 2007 for the U.S. Army Corps of Engineers, Portland District, to characterize the effects of total dissolved gas (TDG) on the incubating fry of chum salmon (Onchorhynchus keta) in the lower Columbia River. The tasks conducted and results obtained in pursuit of three objectives are summarized: * to conduct a field monitoring program at the Ives Island and Multnomah Falls study sites, collecting empirical data on TDG to obtain a more thorough understanding of TDG levels during different river stage scenarios (i.e., high-water year versus low-water year) * to conduct laboratory toxicity tests on hatchery chum salmon fry at gas levels likely to occur downstream from Bonneville Dam * to sample chum salmon sac fry during Bonneville Dam spill operations to determine if there is a physiological response to TDG levels. Chapter 1 discusses the field monitoring, Chapter 2 reports the findings of the laboratory toxicity tests, and Chapter 3 describes the field-sampling task. Each chapter contains an objective-specific introduction, description of the study site and methods, results of research, and discussion of findings. Literature cited throughout this report is listed in Chapter 4. Additional details on the study methdology and results are provided in Appendixes A through D.

  7. Total Dissolved Gas Effects on Incubating Chum Salmon Below Bonneville Dam

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Hand, Kristine D.; Carter, Kathleen M.; Geist, David R.; Murray, Katherine J.; Dawley, Earl M.; Cullinan, Valerie I.; Elston, Ralph A.; Vavrinec, John

    2009-01-29

    At the request of the U.S. Army Corps of Engineers (USACE; Portland District), Pacific Northwest National Laboratory (PNNL) undertook a project in 2006 to look further into issues of total dissolved gas (TDG) supersaturation in the lower Columbia River downstream of Bonneville Dam. In FY 2008, the third year of the project, PNNL conducted field monitoring and laboratory toxicity testing to both verify results from 2007 and answer some additional questions about how salmonid sac fry respond to elevated TDG in the field and the laboratory. For FY 2008, three objectives were 1) to repeat the 2006-2007 field effort to collect empirical data on TDG from the Ives Island and Multnomah Falls study sites; 2) to repeat the static laboratory toxicity tests on hatchery chum salmon fry to verify 2007 results and to expose wild chum salmon fry to incremental increases in TDG, above those of the static test, until external symptoms of gas bubble disease were clearly present; and 3) to assess physiological responses to TDG levels in wild chum salmon sac fry incubating below Bonneville Dam during spill operations. This report summarizes the tasks conducted and results obtained in pursuit of the three objectives. Chapter 1 discusses the field monitoring, Chapter 2 reports the findings of the laboratory toxicity tests, and Chapter 3 describes the field-sampling task. Each chapter contains an objective-specific introduction, description of the study site and methods, results of research, and discussion of findings. Literature cited throughout this report is listed in Chapter 4. Additional details on the monitoring methodology and results are provided in Appendices A and B included on the compact disc bound inside the back cover of the printed version of this report.

  8. Fabrication of ATALANTE Dissolver Off-Gas Sorbent-Based Capture System

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Jr., Joseph Franklin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-30

    A small sorbent-based capture system was designed that could be placed in the off-gas line from the fuel dissolver in the ATALANTE hot cells with minimal modifications to the ATALANTE dissolver off-gas system. Discussions with personnel from the ATALANTE facility provided guidance that was used for the design. All components for this system have been specified, procured, and received on site at Oak Ridge National Laboratory (ORNL), meeting the April 30, 2015, milestone for completing the fabrication of the ATALANTE dissolver off-gas capture system. This system will be tested at ORNL to verify operation and to ensure that all design requirements for ATALANTE are met. Modifications to the system will be made, as indicated by the testing, before the system is shipped to ATALANTE for installation in the hot cell facility.

  9. Novel Apparatus for the Real-Time Quantification of Dissolved Gas Concentrations and Isotope Ratios

    Science.gov (United States)

    Gupta, M.; Leen, J.; Baer, D. S.; Owano, T. G.; Liem, J.

    2013-12-01

    Measurements of dissolved gases and their isotopic composition are critical in studying a variety of phenomena, including underwater greenhouse gas generation, air-surface exchange, and pollution migration. These studies typically involve obtaining water samples from streams, lakes, or ocean water and transporting them to a laboratory, where they are degased. The gases obtained are then generally measured using gas chromatography and isotope ratio mass spectrometry for concentrations and isotope ratios, respectively. This conventional, off-line methodology is time consuming, significantly limits the number of the samples that can be measured and thus severely inhibits detailed spatial and temporal mapping of gas concentrations and isotope ratios. In this work, we describe the development of a new membrane-based degassing device that interfaces directly to Los Gatos Research (cavity enhanced laser absorption or Off-Axis ICOS) gas analyzers (cavity enhanced laser absorption or Off-Axis ICOS analyzers) to create an autonomous system that can continuously and quickly measure concentrations and isotope ratios of dissolved gases in real time in the field. By accurately controlling the water flow rate through the membrane degasser, gas pressure on the outside of the membrane, and water pressure on the inside of the membrane, the system is able to generate precise and highly reproducible results. Moreover, by accurately measuring the gas flow rates in and out of the degasser, the gas-phase concentrations (ppm) could be converted into dissolved gas concentrations (nM). We will present detailed laboratory test data that quantifies the linearity, precision, and dynamic range of the system for the concentrations and isotope ratios of dissolved methane, carbon dioxide, and nitrous oxide. By interfacing the degassing device to a novel cavity-enhanced spectrometer (developed by LGR), preliminary data will also be presented for dissolved volatile organics (VOC) and other

  10. Adsorptive separation of NOsub(x) from dissolver off-gas

    International Nuclear Information System (INIS)

    Ringel, H.

    1984-06-01

    After precleaning the dissolver off-gas contains, besides the noble gases Xe and Kr, about 0.5 vol.% each of NOsub(x) and H 2 O. For the removal of these NOsub(x) and H 2 O residues to below 1 ppm, an adsorptive gas cleaning process has been developed and tested on a lab-scale. For the process, an acid resistant molecular sieve was selected and its properties investigated with respect to application; e.g. the dependence of the adsorption capacity on temperature, gas composition and face velocity. By the operation of a lab-scale facility with 400 Nl/h continuous off-gas throughput the suitability of the adsorption process has been demonstrated for off-gas cleaning and recycling of the separated NO 2 and H 2 O to the dissolver. (orig.) [de

  11. Continuous in-situ monitoring of dissolved gases for the characterization of the Critical Zone with a MIMS

    Science.gov (United States)

    Chatton, Eliot; Labasque, Thierry; Aquilina, Luc; de la Bernardie, Jérôme; Guihéneuf, Nicolas

    2016-04-01

    In the perspective of a temporal and spatial exploration of the Critical Zone, we developed an in situ monitoring instrument for continuous dissolved gas analysis (N2, O2, CO2, CH4, He, Ne, Ar, Kr, Xe). With a large resolution (5 orders of magnitude) and a capability of high frequency multi-tracer analysis (1 gas every 1.5 seconds), the MIMS (Membrane Inlet Mass Spectrometer) is an innovative tool allowing the investigation of a large panel of physical and biogeochemical processes. First of all, this study presents the results of groundwater tracer tests using dissolved gases in order to evaluate transport properties of a fractured media in Brittany, France (Ploemeur, ORE H+). The tracer test experiment showed that the MIMS is perfectly suitable for field work. The instrument provides precise measurements accurate enough to produce breakthrough curves during groundwater tracer tests. The results derived from 4He data gives transport parameters in good agreement with the results obtained with a fluorescent tracer. Combined with a pump and a multi-parameter probe, the MIMS is also capable to perform accurate dissolved gases well-logs allowing a real-time estimation of recharge conditions (temperature, excess air), aquifer stratification, redox conditions and groundwater residence time by 4He dating. Therefore, the MIMS is a valuable tool for in situ characterization of biogeochemical reactivity in aquatic systems, the determination of aquifer transport properties, the monitoring of groundwater recharge conditions and the characterization of aquifer-river exchanges.

  12. Gas bubble disease monitoring and research of juvenile salmonids

    International Nuclear Information System (INIS)

    Maule, A.G.; Beeman, J.; Hans, K.M.; Mesa, M.G.; Haner, P.; Warren, J.J.

    1997-10-01

    This document describes the project activities 1996--1997 contract year. This report is composed of three chapters which contain data and analyses of the three main elements of the project: field research to determine the vertical distribution of migrating juvenile salmonids, monitoring of juvenile migrants at dams on the Snake and Columbia rivers, and laboratory experiments to describe the progression of gas bubble disease signs leading to mortality. The major findings described in this report are: A miniature pressure-sensitive radio transmitter was found to be accurate and precise and, after compensation for water temperature, can be used to determine the depth of tagged-fish to within 0.32 m of the true depth (Chapter 1). Preliminary data from very few fish suggest that depth protects migrating juvenile steelhead from total dissolved gas supersaturation (Chapter 1). As in 1995, few fish had any signs of gas bubble disease, but it appeared that prevalence and severity increased as fish migrated downstream and in response to changing gas supersaturation (Chapter 2). It appeared to gas bubble disease was not a threat to migrating juvenile salmonids when total dissolved gas supersaturation was < 120% (Chapter 2). Laboratory studies suggest that external examinations are appropriate for determining the severity of gas bubble disease in juvenile salmonids (Chapter 3). The authors developed a new method for examining gill arches for intravascular bubbles by clamping the ventral aorta to reduce bleeding when arches were removed (Chapter 3). Despite an outbreak of bacterial kidney disease in the experimental fish, the data indicate that gas bubble disease is a progressive trauma that can be monitored (Chapter 3)

  13. Raman spectroscopy measurement of CH4 gas and CH4 dissolved in water for laser remote sensing in water

    Science.gov (United States)

    Somekawa, Toshihiro; Fujita, Masayuki

    2018-04-01

    We examined the applicability of Raman spectroscopy as a laser remote sensing tool for monitoring CH4 in water. The Raman technique has already been used successfully for measurements of CO2 gas in water. In this paper, considering the spectral transmittance of water, third harmonics of Q-switched Nd:YAG laser at 355 nm (UV region) was used for detection of CH4 Raman signals. The Raman signal at 2892 cm-1 from CH4 dissolved in water was detected at a tail of water Raman signal.

  14. Feasibility study for evaluating cumulative exposure of downstream migrant juvenile salmonids to total dissolved gas. Final report

    International Nuclear Information System (INIS)

    Abernethy, C.S.; Dauble, D.D.; Johnson, R.L.

    1997-11-01

    A feasibility study was initiated to determine if downstream migrant salmonids could be monitored to determine potential relationships between total dissolved gas (TDG) exposure and signs of gas bubble trauma (GBT). The primary objectives were to: (1) establish logistical requirements for in-river monitoring of TDG exposure, including net pen design, deployment, and navigation constraints; (2) resolve uncertainties associated with effects of the net pen on fish behavior; (3) test the accuracy and precision of in-river monitoring equipment used to measure fish distribution and water quality; and (4) determine the application of hydrologic/flow models to predictions of TDG exposure. In-river measurements included water velocity, boat position, and selected water quality parameters (temperature, dissolved oxygen, pH, depth, conductivity). Fish distribution within the net pen was monitored using scanning sonar, and a split-beam echo sounder was used to evaluate vertical distribution of fish m in the river adjacent to the net pen. Three test drifts were conducted from late July through late August. The studies demonstrated that it was feasible to assemble and deploy a large net pen for mobile monitoring of TDG exposure. Accurate monitoring of vertical and lateral distribution of smolts was performed, and diel differences in behavior were documented. Further, the fish sounded in response to researcher activity on the perimeter platform. Thus, in-transit monitoring for GBT or mortality would affect fish depth distribution and exposure to TDG. Principal recommendations for future studies are directed at improving maneuverability of the net pen in adverse weather conditions and applying new acoustics technology to simultaneously collect fish distribution data from within and outside of the pen. 6 refs., 17 figs., 2 tabs

  15. Multi-Gas Monitor (MGM)

    Science.gov (United States)

    Pilgrim, Jeff; Limero, Thomas

    2015-01-01

    Multi-Gas Monitor is a flight experiment, a technology demonstration to test the ability of tunable diode laser spectroscopy based instrument to stay in calibration long term and follow events and dynamics occurring with the cabin atmosphere. MGM measures 4 gases: oxygen, carbon monoxide, ammonia and water vapor, as well as temperature and pressure. This month marked one year of successful and continuous MGM operation on ISS. The crew successfully tested the ammonia channel using a commercially available inhalant. MGM has detected some interesting dynamics inside Japanese Experiment Module (JEM) as a result of CO2 thruster firings from the SPHERES/RINGS payload and water spikes from dry out cycling of the JEM heat exchangers. Results to date have given us high confidence in the technology such that we believe this could have applications in the energy and medical sectors. This presentation will summarize the testing and results of the unit on ISS and suggest areas of use within the energy and medical arenas.

  16. Dissolved atmospheric gas in xylem sap measured with membrane inlet mass spectrometry.

    Science.gov (United States)

    Schenk, H Jochen; Espino, Susana; Visser, Ate; Esser, Bradley K

    2016-04-01

    A new method is described for measuring dissolved gas concentrations in small volumes of xylem sap using membrane inlet mass spectrometry. The technique can be used to determine concentrations of atmospheric gases, such as argon, as reported here, or for any dissolved gases and their isotopes for a variety of applications, such as rapid detection of trace gases from groundwater only hours after they were taken up by trees and rooting depth estimation. Atmospheric gas content in xylem sap directly affects the conditions and mechanisms that allow for gas removal from xylem embolisms, because gas can dissolve into saturated or supersaturated sap only under gas pressure that is above atmospheric pressure. The method was tested for red trumpet vine, Distictis buccinatoria (Bignoniaceae), by measuring atmospheric gas concentrations in sap collected at times of minimum and maximum daily temperature and during temperature increase and decline. Mean argon concentration in xylem sap did not differ significantly from saturation levels for the temperature and pressure conditions at any time of collection, but more than 40% of all samples were supersaturated, especially during the warm parts of day. There was no significant diurnal pattern, due to high variability between samples. © 2015 John Wiley & Sons Ltd.

  17. Monitoring gas quality green gas feeding in; Monitoring gaskwaliteit groengasinvoeding

    Energy Technology Data Exchange (ETDEWEB)

    Holstein, J. [DNV KEMA Energy and Sustainability, Arnhem (Netherlands); Polman, E. [Kiwa Technology, Apeldoorn (Netherlands)

    2013-04-15

    Due to the growing number of green gas facilities in the Netherlands more practical knowledge is collected about the production and injection of green gas. Also there was the need to gather data about more practical experiences and knowledge about the gas quality, the performance of gas cleaning and gas treatment systems, as well the integration of green gas in the gas infrastructure. In addition to this, there is a need to get insight in the safety aspects of green gas injection. In order to comply this demand, DNV KEMA en Kiwa Technology measured the quality parameters continuously between June 2012 en January 2013 (three weeks) and discontinuously (gas samples) of green gas at eight production facilities. The measurements have been performed at designated places and are independent from the measurements of the biomethane producer. In order to be sure that the results of DNV KEMA and Kiwa are comparable, a combined measurement program was executed. It results in uniformity for all the measured values: the differences are within the uncertainty level for each component. During the measurement period of three weeks, the gas quality parameters were compared to specifications, written down in the national regulations for the transport and the distribution grid respectively [Dutch] Door het groeiend aantal groengasinvoedingen in Nederland wordt steeds meer praktijkkennis verzameld. Er dient meer praktijkkennis te worden verzameld over de chemische gaskwaliteit, prestaties van de gasreiniging- en gasopwaardering en de wijze van inpassing in de bestaande infrastructuur. Daarnaast is het wenselijk om inzicht te verkrijgen in de veiligheid van groengasinvoeding. Daarop is de groengaskwaliteit op acht locaties over een periode van drie weken continu en discontinu gemeten tussen juni 2012 en januari 2013. De metingen zijn uitgevoerd op een aangewezen plaats door de netbeheerder en staan los van de metingen van de invoeders zelf. Voor het waarborgen van de uniformiteit van

  18. Prediction of Dissolved Gas Concentrations in Transformer Oil Based on the KPCA-FFOA-GRNN Model

    Directory of Open Access Journals (Sweden)

    Jun Lin

    2018-01-01

    Full Text Available The purpose of analyzing the dissolved gas in transformer oil is to determine the transformer’s operating status and is an important basis for fault diagnosis. Accurate prediction of the concentration of dissolved gas in oil can provide an important reference for the evaluation of the state of the transformer. A combined predicting model is proposed based on kernel principal component analysis (KPCA and a generalized regression neural network (GRNN using an improved fruit fly optimization algorithm (FFOA to select the smooth factor. Firstly, based on the idea of using the dissolved gas ratio of oil to diagnose the transformer fault, gas concentration ratios are also used as characteristic parameters. Secondly, the main parameters are selected from the feature parameters using the KPCA method, and the GRNN is then used to predict the gas concentration in the transformer oil. In the training process of the network, the FFOA is used to select the smooth factor of the neural network. Through a concrete example, it is shown that the method proposed in this paper has better data fitting ability and more accurate prediction ability compared with the support vector machine (SVM and gray model (GM methods.

  19. Burner and dissolver off-gas treatment in HTR fuel reprocessing

    International Nuclear Information System (INIS)

    Barnert-Wiemer, H.; Heidendael, M.; Kirchner, H.; Merz, E.; Schroeder, G.; Vygen, H.

    1979-01-01

    In the reprocessing of HTR fuel, essentially all of the gaseous fission products are released during the heat-end tratment, which includes burning of the graphite matrix and dissolving of the heavy metallic residues in THOREX reagent. Three facilities for off-gas cleaning are described, the status of the facility development and test results are reported. Hot tests with a continuous dissolver for HTR-type fuel (throughput 2 kg HM/d) with a closed helium purge loop have been carried out. Preliminary results of these experiments are reported

  20. On-line fast response device and method for measuring dissolved gas in a fluid

    Science.gov (United States)

    Tutu, Narinder Kumar [Manorville, NY

    2011-01-11

    A method and device for the measurement of dissolved gas within a fluid. The fluid, substantially a liquid, is pumped into a pipe. The flow of the fluid is temporally restricted, creating one or more low pressure regions. A measurement indicative of trapped air is taken before and after the restriction. The amount of dissolved air is calculated from the difference between the first and second measurements. Preferably measurements indicative of trapped air is obtained from one or more pressure transducers, capacitance transducers, or combinations thereof. In the alternative, other methods such as those utilizing x-rays or gamma rays may also be used to detect trapped air. Preferably, the fluid is a hydraulic fluid, whereby dissolved air in the fluid is detected.

  1. Gasometer: An inexpensive device for continuous monitoring of dissolved gases and supersaturation

    Science.gov (United States)

    Bouck, G.R.

    1982-01-01

    The “gasometer” is a device that measures differential dissolved-gas pressures (δP) in water relative to barometric pressure (as does the “Weiss saturometer”), but operates continuously without human attention. The gasometer can be plumbed into a water-supply system and requires 8 liters/minute of water or more at 60 kilopascals. The gasometer's surfaces are nontoxic, and flow-through water can be used for fish culture. The gasometer may be connected to a small submersible pump and operated as a portable unit. The gasometer can activate an alarm system and thus protect fish from hyperbaric (supersaturation) or hypobaric gas pressures (usually due to low dissolved oxygen). Instructions are included for calculating and reporting data including the pressure and saturation of individual gases. Construction and performance standards are given for the gasometer. Occasional cleaning is required to remove biofouling from the gas-permeable tubing.PDF

  2. Ice Harbor Spillway Dissolved Gas Field Studies: Before and After Spillway Deflectors

    Science.gov (United States)

    2016-07-01

    Steven C. Wilhelms Coastal And Hydraulics Laboratory U.S. Army Engineer Research and Development Center 3909 Halls Ferry Road Vicksburg, Mississippi...Harbor as a measure to reduce the total dissolved gas (TDG) production during spill operations. Three field studies were conducted at the Ice Harbor...significantly reduced for nearly all spill operations with deflectors in place. TDG near the stilling basin was reduced from approximately 150% to

  3. Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A.

    2009-09-14

    Migratory and resident fish in the Columbia River Basin are exposed to stresses associated with hydroelectric power production, including changes in pressure as they pass through turbines and dissolved gas supersaturation (resulting from the release of water from the spillway). To examine pressure changes as a source of turbine-passage injury and mortality, Pacific Northwest National Laboratory scientists conducted specific tests using a hyperbaric chamber. Tests were designed to simulate Kaplan turbine passage conditions and to quantify the response of fish to rapid pressure changes, with and without the complication of fish being acclimated to gas-supersaturated water.

  4. Studies in the dissolver off-gas system for a spent FBR fuel reprocessing plant

    International Nuclear Information System (INIS)

    Heinrich, E.; Huefner, R.; Weirich, F.

    1982-01-01

    Investigations of possible modifications of the process steps of a dissolver off-gas (DOG) system for a spent FBR fuel reprocessing plant are reported. The following operations are discussed: iodine removal from the fuel solution; behaviour of NOsub(x) and iodine in nitric acid off-gas scrubbers at different temperatures and nitric acid concentrations; iodine desorption from the scrub acid; selective absorption of noble gases in refrigerant-12; cold traps. The combination of suitable procedures to produce a total DOG system is described. (U.K.)

  5. Recharge processes and vertical transfer investigated through long-term monitoring of dissolved gases in shallow groundwater

    Science.gov (United States)

    de Montety, V.; Aquilina, L.; Labasque, T.; Chatton, E.; Fovet, O.; Ruiz, L.; Fourré, E.; de Dreuzy, J. R.

    2018-05-01

    We investigated temporal variations and vertical evolution of dissolved gaseous tracers (CFC-11, CFC-12, SF6, and noble gases), as well as 3H/3He ratio to determine groundwater recharge processes of a shallow unconfined, hard-rock aquifer in an agricultural catchment. We sampled dissolved gas concentration at 4 locations along the hillslope of a small experimental watershed, over 6 hydrological years, between 2 and 6 times per years, for a total of 20 field campaigns. We collected groundwater samples in the fluctuation zone and the permanently saturated zone using piezometers from 5 to 20 m deep. The purpose of this work is i) to assess the benefits of using gaseous tracers like CFCs and SF6 to study very young groundwater with flows suspected to be heterogeneous and variable in time, ii) to characterize the processes that control dissolved gas concentrations in groundwater during the recharge of the aquifer, and iii) to understand the evolution of recharge flow processes by repeated measurement campaigns, taking advantage of a long monitoring in a site devoted to recharge processes investigation. Gas tracer profiles are compared at different location of the catchment and for different hydrologic conditions. In addition, we compare results from CFCs and 3H/3He analysis to define the flow model that best explains tracer concentrations. Then we discuss the influence of recharge events on tracer concentrations and residence time and propose a temporal evolution of residence times for the unsaturated zone and the permanently saturated zone. These results are used to gain a better understanding of the conceptual model of the catchment and flow processes especially during recharge events.

  6. Ionization chamber for monitoring radioactive gas

    International Nuclear Information System (INIS)

    Kotrappa, P.; Dempsey, J.

    1992-01-01

    This present invention provides simple, effective and accurate cumulative measurement of radioactive gas over a time period. Measurements of radioactive gas are important for many purposes. Tritium concentrations in potentially exposed workers are measured, for example, with periodic urine specimens. Carbon-14 serves as a useful research tool for monitoring the progress of many chemical and biological reactions and interactions. For example, many microorganisms break down carbon-14 containing compounds in sugar to produce carbon-14 dioxide gas which can be collected and measured to determine various characteristics of the microorganisms. Both tritium and carbon-14 dioxide produce low energy radiation which cannot be easily measured by conventional radioactivity detectors. (author). 4 figs

  7. Ionization chamber for monitoring radioactive gas

    Energy Technology Data Exchange (ETDEWEB)

    Kotrappa, P; Dempsey, J

    1992-09-22

    This present invention provides simple, effective and accurate cumulative measurement of radioactive gas over a time period. Measurements of radioactive gas are important for many purposes. Tritium concentrations in potentially exposed workers are measured, for example, with periodic urine specimens. Carbon-14 serves as a useful research tool for monitoring the progress of many chemical and biological reactions and interactions. For example, many microorganisms break down carbon-14 containing compounds in sugar to produce carbon-14 dioxide gas which can be collected and measured to determine various characteristics of the microorganisms. Both tritium and carbon-14 dioxide produce low energy radiation which cannot be easily measured by conventional radioactivity detectors. (author). 4 figs.

  8. Dissolved gas geochemical signatures of the ground waters related to the 2011 El Hierro magmatic reactivation

    Science.gov (United States)

    Rodríguez, F.; Hernández, P. A.; Padrón, E.; Pérez, N. M.; Sumino, H.; Melián, G. V.; Padilla, G. D.; Barrancos, J.; Dionis, S.; Nolasco, D.; Calvo, D.; Hernández, I.; Peraza, M. D.

    2012-04-01

    El Hierro Island is the south westernmost and the youngest island of the Canary archipelago (Restinga village (at the southernmost part of El Hierro island), suggesting the existence of a submarine eruption. Since October 12, frequent episodes of, turbulent gas emission and foaming, and the appearance of steamy lava fragments has been observed on the sea surface. Instituto Volcanologico de Canarias (INVOLCAN) started a hydrogeochemical program on August 2011 in order to evaluate the temporal evolution of dissolved gases on four different observation points (vertical and horizontal wells) of El Hierro. Three wells are located on the north of the island (where the seismic activity occurred at the beginning of the volcano-seismic unrest) and one horizontal well (gallery) in the south. At each observation point the concentration of dissolved helium, CO2, N2, O2 and Ar and the isotopic composition of He, C-CO2 and Ar have been measured three times per week. Significant increases on the dissolved gases content, mainly on CO2 and He/CO2 ratio, have been measured at all the observation points prior to the increasing of released seismic energy. Isotopic composition of dissolved helium, measured as 3He/4He ratio, showed an significant increase (from 1-3 RA up to 7.2 RA, being RA the isotopic 3He/4He ratio on air) at all the observation points 20 days before the occurrence of the submarine eruption and these relatively high 3He/4He values have been maintained along the volcanic unrest period. The isotopic composition of CO2 has showed also significant changes in relation to the release of seismic energy. The results observed on this dissolved gases study have been tremendously beneficial on the volcanic surveillance tools to study and forecast the evolution of the seismic-volcanic crisis.

  9. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    Energy Technology Data Exchange (ETDEWEB)

    Prasetyaningrum, A., E-mail: ajiprasetyaningrum@gmail.com; Ratnawati,; Jos, B. [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. H. Soedarto Tembalang, Semarang, Central Java, Indonesia, 50276 (Indonesia)

    2015-12-29

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O{sub 3}) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.

  10. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    International Nuclear Information System (INIS)

    Prasetyaningrum, A.; Ratnawati,; Jos, B.

    2015-01-01

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O 3 ) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV

  11. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    Science.gov (United States)

    Prasetyaningrum, A.; Ratnawati, Jos, B.

    2015-12-01

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O3) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.

  12. Design, Fabrication, and Shakeout Testing of ATALANTE Dissolver Off-Gas Sorbent-Based Capture System

    International Nuclear Information System (INIS)

    Walker Jr, Joseph Franklin; Jubin, Robert Thomas; Jordan, Jacob A.; Bruffey, Stephanie H.

    2015-01-01

    A sorbent-based capture system designed for integration into the existing dissolver off-gas (DOG) treatment system at the ATelier Alpha et Laboratoires pour ANalyses, Transuraniens et Etudes de retraitement (ATALANTE) facility has been successfully designed and fabricated and has undergone shakeout testing. Discussions with personnel from the ATALANTE facility provided guidance that was used for the design. All components for this system were specified, procured, and received on site at Oak Ridge National Laboratory (ORNL). The system was then fabricated and tested at ORNL to verify operation. Shakeout testing resulted in a simplified system. This system should be easily installed into the existing facility and should be straightforward to operate during future experimental testing. All parts were selected to be compatible with ATALANTE power supplies, space requirements, and the existing DOG treatment system. Additionally, the system was demonstrated to meet all of four design requirements. These include (1) a dissolver off-gas flow rate of ?100 L/h (1.67 L/min), (2) an external temperature of ?50°C for all system components placed in the hot cell, (3) a sorbent bed temperature of ~150°C, and (4) a gas temperature of ~150°C upon entry into the sorbent bed. The system will be ready for shipment and installation in the existing DOG treatment system at ATALANTE in FY 2016.

  13. Tiger: knowledge based gas turbine condition monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Trave-Massuyes, L. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Quevedo, J. [University of Catalonia, (Spain); Milne, R.; Nicol, Ch.

    1995-12-31

    Exxon petrochemical plant in Scotland requires continuous ethylene supply from offshore site in North Sea. The supply is achieved thanks to compressors driven by a 28 MW gas turbine, whose monitoring is of major importance. The TIGER fault diagnostic system is a knowledge base system containing a prediction model. (D.L.) 11 refs.

  14. Tiger: knowledge based gas turbine condition monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Trave-Massuyes, L [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Quevedo, J [University of Catalonia, (Spain); Milne, R; Nicol, Ch

    1996-12-31

    Exxon petrochemical plant in Scotland requires continuous ethylene supply from offshore site in North Sea. The supply is achieved thanks to compressors driven by a 28 MW gas turbine, whose monitoring is of major importance. The TIGER fault diagnostic system is a knowledge base system containing a prediction model. (D.L.) 11 refs.

  15. Gas chromatography in blood carbon monoxide monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Drasche, H.; Funk, L.; Herbolsheimer, R.

    1975-05-01

    A description of a gas chromatography method for monitoring blood carboxyhaemoglobin (HbCO) levels in a very small quantity (100 mcl) of capillary blood: reagents and apparatus, procedures, calculation of results. To calculate HbCO content, an aliquot portion of water-diluted blood is saturated with CO; this saturation obviates the need to determine the haemoglobin or iron blood levels.

  16. Gas monitoring onboard ISS using FTIR spectroscopy

    Science.gov (United States)

    Gisi, Michael; Stettner, Armin; Seurig, Roland; Honne, Atle; Witt, Johannes; Rebeyre, Pierre

    2017-06-01

    In the confined, enclosed environment of a spacecraft, the air quality must be monitored continuously in order to safeguard the crew's health. For this reason, OHB builds the ANITA2 (Analysing Interferometer for Ambient Air) technology demonstrator for trace gas monitoring onboard the International Space Station (ISS). The measurement principle of ANITA2 is based on the Fourier Transform Infrared (FTIR) technology with dedicated gas analysis software from the Norwegian partner SINTEF. This combination proved to provide high sensitivity, accuracy and precision for parallel measurements of 33 trace gases simultaneously onboard ISS by the precursor instrument ANITA1. The paper gives a technical overview about the opto-mechanical components of ANITA2, such as the interferometer, the reference Laser, the infrared source and the gas cell design and a quick overview about the gas analysis. ANITA2 is very well suited for measuring gas concentrations specifically but not limited to usage onboard spacecraft, as no consumables are required and measurements are performed autonomously. ANITA2 is a programme under the contract of the European Space Agency, and the air quality monitoring system is a stepping stone into the future, as a precursor system for manned exploration missions.

  17. Design and Implementation of Remotely Monitoring System for Total Dissolved Solid in Baghdad Drinking Water Networks

    Directory of Open Access Journals (Sweden)

    Hussein Abdul-Ridha Mohammed

    2018-01-01

    Full Text Available he pollution of drinking water is a dangerous problem for the whole world, it can threaten the health of people and as people in developed society attaches more importance to environmental protection, it is of great research significance to intelligently and remotely monitoring the environment. Therefore in this paper, a remote water monitoring system for Baghdad drinking water system is suggested. The proposed system consists of data sensing and monitoring nodes at different locations in Baghdad to sensing and analyzes the data. These nodes are periodically measured Total Dissolved Solids (TDS. In case of measured value above TDS threshold which is 500 ppm, then an automated warning message will be sent to authorize persons in the maintenance center via Global Position System to take the correct action. This suggested structure has several advantages over traditional monitoring systems in terms of price, portability, reliability, applicability and takes a sample from a water tap in easy and real-time approach.

  18. Low-level radioactive gas monitor for natural gas operations

    International Nuclear Information System (INIS)

    Armstrong, F.E.

    1969-11-01

    A portable radioactivity detection system for monitoring the tritium content of natural gas under field conditions has been developed. The sensing device employed is a complex proportional counting assembly operated without the use of massive shielding previously employed with such low-level radiation detectors. The practical limit of detection for the system is a tritium content of 10 -9 microcurie per cc of natural gas. All components of the system are packaged in three waterproof cases weighing slightly less than 30 kg each. Power requirement is 500 watts of 120 volt, 60 Hz current. Operation is fully automatic with a printed record produced at predetermined time intervals

  19. Water and dissolved gas geochemistry of the monomictic Paterno sinkhole (central Italy

    Directory of Open Access Journals (Sweden)

    Matteo Nocentini

    2012-07-01

    Full Text Available This paper describes the chemical and isotope features of water and dissolved gases from lake Paterno (max. depth 54 m, a sinkhole located in the NE sector of the S. Vittorino plain (Rieti, Central Italy, where evidences of past and present hydrothermal activity exists. In winter (February 2011 lake Paterno waters were almost completely mixed, whereas in summer time (July 2011 thermal and chemical stratifications established. During the stratification period, water and dissolved gas chemistry along the vertical water column were mainly controlled by biological processes, such as methanogenesis, sulfate-reduction, calcite precipitation, denitrification, and NH4 and H2 production. Reducing conditions at the interface between the bottom sediments and the anoxic waters are responsible for the relatively high concentrations of dissolved iron (Fe and manganese (Mn, likely present in their reduced oxidation state. Minerogenic and biogenic products were recognized at the lake bottom even during the winter sampling. At relatively shallow depth the distribution of CH4 and CO2 was controlled by methanotrophic bacteria and photosynthesis, respectively. The carbon isotope signature of CO2 indicates a significant contribution of deep-originated inorganic CO2 that is related to the hydrothermal system feeding the CO2-rich mineralized springs discharging in the surrounding areas of lake Paterno. The seasonal lake stratification likely controls the vertical and horizontal distribution of fish populations in the different periods of the year.

  20. Potential for a process-based monitoring method above geologic carbon storage sites using dissolved gases in freshwater aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Romanak, Katherine [Gulf Coast Carbon Center, Bureau of Economic Geology, The University of Texas at Austin, TX 78713 (United States); Dobeck, Laura; Spangler, Lee [Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717 (United States); Dixon, Tim [IEA Greenhouse Gas R and D Programme, Cheltenham GL52 7RZ (United Kingdom)

    2013-07-01

    The process-based method is a new technique for monitoring CO{sub 2} storage permanence in the vadose zone above geologic carbon storage (GCS) sites. This method uses ratios of coexisting gas species to understand geochemical processes rather than comparing CO{sub 2} concentrations with large baseline data sets, thereby making monitoring more efficient. In the vadose zone, ratios among coexisting gases (CO{sub 2}, O{sub 2}, N{sub 2} and CH{sub 4}) have been used to distinguish biologic respiration, water-rock-CO{sub 2} interaction, and methane oxidation from a leakage signal. We report the preliminary results of a feasibility test conducted in July 2012 at the Zero Emission Research and Technology Center (ZERT) controlled release site in Montana, USA to discern whether the method could be applied to dissolved gases in groundwater, thereby enhancing groundwater monitoring. Preliminary results are favorable, making the process-based approach potentially useful for monitoring shallow freshwater aquifers above GCS sites. (authors)

  1. Gas-Liquid Precipitation of water dissolved heavy metal ions using hydrogen sulfide gas

    NARCIS (Netherlands)

    Al Tarazi, M.Y.M.

    2004-01-01

    Precipitation of solids promoted by gas-liquid reactions is applied in many industrial processes such as the production of ammonium phosphate, ammonium sulphate, barium carbonate, calcium carbonate, calcium fluoride, ypsum (calcium sulphate), goethite, sodium bicarbonate, strontium carbonate and

  2. FFTF fission gas monitor computer system

    International Nuclear Information System (INIS)

    Hubbard, J.A.

    1987-01-01

    The Fast Flux Test Facility (FFTF) is a liquid-metal-cooled test reactor located on the Hanford site. A dual computer system has been developed to monitor the reactor cover gas to detect and characterize any fuel or test pin fission gas releases. The system acquires gamma spectra data, identifies isotopes, calculates specific isotope and overall cover gas activity, presents control room alarms and displays, and records and prints data and analysis reports. The fission gas monitor system makes extensive use of commercially available hardware and software, providing a reliable and easily maintained system. The design provides extensive automation of previous manual operations, reducing the need for operator training and minimizing the potential for operator error. The dual nature of the system allows one monitor to be taken out of service for periodic tests or maintenance without interrupting the overall system functions. A built-in calibrated gamma source can be controlled by the computer, allowing the system to provide rapid system self tests and operational performance reports

  3. Integrated Microfluidic Gas Sensors for Water Monitoring

    Science.gov (United States)

    Zhu, L.; Sniadecki, N.; DeVoe, D. L.; Beamesderfer, M.; Semancik, S.; DeVoe, D. L.

    2003-01-01

    A silicon-based microhotplate tin oxide (SnO2) gas sensor integrated into a polymer-based microfluidic system for monitoring of contaminants in water systems is presented. This device is designed to sample a water source, control the sample vapor pressure within a microchannel using integrated resistive heaters, and direct the vapor past the integrated gas sensor for analysis. The sensor platform takes advantage of novel technology allowing direct integration of discrete silicon chips into a larger polymer microfluidic substrate, including seamless fluidic and electrical interconnects between the substrate and silicon chip.

  4. Subsurface Monitor for Dissolved Inorganic Carbon at Geological Sequestration Site Phase 1 SBIR Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sheng Wu

    2012-08-03

    Phase I research of this SBIR contract has yielded anticipated results and enable us to develop a practical new instrument to measure the Dissolved Inorganic Carbons (DIC) as well as Supercritical (SC) CO2 in underground brine water at higher sensitivity, lower cost, higher frequency and longer period of time for the Monitoring, Verification & Accounting (MVA) of CO2 sequestration as well as Enhanced Oil Recovery (EOR). We show that reduced cost and improved performance are possible; both future and emerging market exist for the proposed new instrument.

  5. Homogeneous bubble nucleation in binary systems of liquid solvent and dissolved gas

    Czech Academy of Sciences Publication Activity Database

    Němec, Tomáš

    2016-01-01

    Roč. 467, March (2016), s. 26-37 ISSN 0301-0104 R&D Projects: GA ČR GAP101/10/1819; GA ČR GA13-23550S Institutional support: RVO:61388998 Keywords : bubble nucleation * binary nucleation theory * dissolved gas Subject RIV: BJ - Thermodynamics Impact factor: 1.767, year: 2016 http://ac.els-cdn.com/S0301010416000124/1-s2.0-S0301010416000124-main.pdf?_tid=7797c8a0-fb13-11e5-ba55-00000aab0f6c&acdnat=1459849853_b9a5413fefc3e9199e844a9ccc97f514

  6. The source and behavior of iodine dissolving in groundwater in the Mobara gas field, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Gento [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan). Tokai Works

    2002-06-01

    The groundwater of the Mobara gas-field in Boso peninsula, eastern Japan, contains considerable amount, around 100 mg/L, of iodine besides dissolved methane. Twelve groundwater samples from gas-producing wells to the aquifer within the Kazusa Group in Mobara and Naruto districts have been analyzed for iodine, pH, Eh, HCO{sub 3}{sup -}, NH{sub 4}{sup +}, SiO{sub 2}(aq), {delta}D, {delta}{sup 18}O, {delta}{sup 13}C{sub CH4} and seventeen elements. There is a good correlation between the concentrations of the dissolved elements to those in marine algae. The principal source of the iodine is believed to be algae buried in the sediments and the iodine has been discharged to the porefluid during decomposition of the tissue. The molar ratio of I{sup -}/Cl{sup -} in the groundwater increases from 1.0 x 10{sup 3} to 2.2 x 10{sup 3} with changing the depth from 2000 to 1000 meters below the surface and turns to decrease from 2.2 x 10{sup 3} to 1.8 x 10{sup 3} with going up from 1000 to 500 meters. This tendency may be caused by the variation of buried organisms due to changing the sedimentary environment. The observed variation in the ratio indicates that the iodine discharged in the pore fluid did not migrate significantly after the deposition of the formation. This paper can be regarded as an English version of Japanese article written by Kamei, which was published on the 'Shigen Chishitsu (Resource Geology)' 51(2)145-151(2000). (author)

  7. Monitoring greenhouse gas emissions from landfill sites

    International Nuclear Information System (INIS)

    Eade, G.

    2001-01-01

    Methane is the chief component of natural gas, but also occurs naturally by the anaerobic decomposition of organic matter in swamp areas, at landfill sites, in fact at any location where organic deposits are present. Carbon dioxide is also produced by the decomposition of organic material as well as being the primary by-product of combustion. This article focuses on techniques to test a wide variety of combustible and toxic gases, including surface emission testing of landfill sites. Specifically, it describes the Methane Emission Monitoring System (MEMS) developed by Hetek Solutions Inc., whose primary objective is to to effectively locate surface emissions of methane gas from active landfill sites using flame ionization (FI) technology, and to plot the 'hot spots' using a Differential Global Positioning System (DGPS), which provides sub-metre accuracy for plotting emissions locations at landfill sites. The FI equipment is installed on all-terrain vehicles (ATVs). Several thousand kilometers of pipeline inspections have been performed in Alberta and Saskatchewan using this system in the mid-1990s. The mobile FI/ATV units have been redesigned for landfill gas emission testing, equipped with new DGPS equipment and interface software. They meet the New Source Performance Standards (NSPS) drafted in the United States in 1996, which requires all landfill sites to be inspected for methane gas emissions. Using the FI/ATV combination, productivity over conventional walking inspection procedures increased some 400 per cent, while monitoring accuracy is equivalent to or better than those provided by previous conventional methods. The company can also provide the Optical Methane Detector (OMD) system using infrared technology. They are capable of performing 14,000 measurements per second, thus providing immediate response. To date, ATV emissions testing has been proven to be very effective in various types of gas detection. When interfaced with DGPS technology, computer

  8. State observers for monitoring gas pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, M.J.; Jones, R.P.; Pritchard, A.J.

    1987-03-01

    This paper describes work performed on collaboration with the British Gas Corporation in relation to the development of algorithms for monitoring the condition of high-pressure gas pipelines. The practical problem considered is that of reconstructing the pressure profile along a single length of pipe from pressure measurements at the end points and a further measurement at an intermediate point along the pipe. The approach adopted is based on the implementation of a finite-dimensional asymptotic state observer derived from consideration of the distributed-parameter properties of the system. The paper includes the results of a computational study in which the observer was evaluated against experimental data corresponding to an 80 km section of pipe. These results indicate that the dynamic observer is capable of providing an accurate estimate of the pressure profile over a complete 24 h demand cycle. 5 refs. (authors).

  9. 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.

  10. Effect of phytoremediation on concentrations of benzene, toluene, naphthalene, and dissolved oxygen in groundwater at a former manufactured gas plant site, Charleston, South Carolina, USA, 1998–2014

    Science.gov (United States)

    Landmeyer, James E.; Effinger, Thomas N.

    2016-01-01

    Concentrations of benzene, toluene, naphthalene, and dissolved oxygen in groundwater at a former manufactured gas plant site near Charleston, South Carolina, USA, have been monitored since the installation of a phytoremediation system of hybrid poplar trees in 1998. Between 2000 and 2014, the concentrations of benzene, toluene, and naphthalene (BT&N) in groundwater in the planted area have decreased. For example, in the monitoring well containing the highest concentrations of BT&N, benzene concentrations decreased from 10,200 µg/L to less than 4000 µg/L, toluene concentrations decreased from 2420 µg/L to less than 20 µg/L, and naphthalene concentrations decreased from 6840 µg/L to less than 3000 µg/L. Concentrations of BT&N in groundwater in all wells were observed to be lower during the summer months relative to the winter months of a particular year during the first few years after installing the phytoremediation system, most likely due to increased transpiration and contaminant uptake by the hybrid poplar trees during the warm summer months; this pathway of uptake by trees was confirmed by the detection of benzene, toluene, and naphthalene in trees during sampling events in 2002, and later in the study in 2012. These data suggest that the phytoremediation system affects the groundwater contaminants on a seasonal basis and, over multiple years, has resulted in a cumulative decrease in dissolved-phase contaminant concentrations in groundwater. The removal of dissolved organic contaminants from the aquifer has resulted in a lower demand on dissolved oxygen supplied by recharge and, as a result, the redox status of the groundwater has changed from anoxic to oxic conditions. This study provides much needed information for water managers and other scientists on the viability of the long-term effectiveness of phytoremediation in decreasing groundwater contaminants and increasing dissolved oxygen at sites contaminated by benzene, toluene, and naphthalene.

  11. Enhancement of organic matter degradation and methane gas production of anaerobic granular sludge by degasification of dissolved hydrogen gas.

    Science.gov (United States)

    Satoh, Hisashi; Bandara, Wasala M K R T W; Sasakawa, Manabu; Nakahara, Yoshihito; Takahashi, Masahiro; Okabe, Satoshi

    2017-11-01

    A hollow fiber degassing membrane (DM) was applied to enhance organic matter degradation and methane gas production of anaerobic granular sludge process by reducing the dissolved hydrogen gas (D-H 2 ) concentration in the liquid phase. DM was installed in the bench-scale anaerobic granular sludge reactors and D-H 2 was removed through DM using a vacuum pump. Degasification improved the organic matter degradation efficiency to 79% while the efficiency was 62% without degasification at 12,000mgL -1 of the influent T-COD concentration. Measurement of D-H 2 concentrations in the liquid phase confirmed that D-H 2 was removed by degasification. Furthermore, the effect of acetate concentrations on the organic matter degradation efficiency was investigated. At acetate concentrations above 3gL -1 , organic matter degradation deteriorated. Degasification enhanced the propionate and acetate degradation. These results suggest that degasification reduced D-H 2 concentration and volatile fatty acids concentrations, prevented pH drop, and subsequent enhanced organic matter degradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Cumulative effects of cascade hydropower stations on total dissolved gas supersaturation.

    Science.gov (United States)

    Ma, Qian; Li, Ran; Feng, Jingjie; Lu, Jingying; Zhou, Qin

    2018-03-01

    Elevated levels of total dissolved gas (TDG) may occur downstream of dams during the spill process. These high levels would increase the incidence of gas bubble disease in fish and cause severe environmental impacts. With increasing numbers of cascade hydropower stations being built or planned, the cumulative effects of TDG supersaturation are becoming increasingly prominent. The TDG saturation distribution in the downstream reaches of the Jinsha River was studied to investigate the cumulative effects of TDG supersaturation resulting from the cascade hydropower stations. A comparison of the effects of the joint operation and the single operation of two hydropower stations (XLD and XJB) was performed to analyze the risk degree to fish posed by TDG supersaturation. The results showed that water with supersaturated TDG generated at the upstream cascade can be transported to the downstream power station, leading to cumulative TDG supersaturation effects. Compared with the single operation of XJB, the joint operation of both stations produced a much higher TDG saturation downstream of XJB, especially during the non-flood discharge period. Moreover, the duration of high TDG saturation and the lengths of the lethal and sub-lethal areas were much higher in the joint operation scenario, posing a greater threat to fish and severely damaging the environment. This work provides a scientific basis for strategies to reduce TDG supersaturation to the permissible level and minimize the potential risk of supersaturated TDG.

  13. Profile Monitors Based on Residual Gas Interaction

    CERN Document Server

    Forck, P; Giacomini, T; Peters, A

    2005-01-01

    The precise determination of transverse beam profiles at high current hadron accelerators has to be performed non-interceptingly. Two methods will be discussed based on the excitation of the residual gas molecules by the beam particles: Firstly, by beam induced fluorescence (BIF) light is emitted from the residual gas molecules and is observed with an image intensified CCD camera. At most laboratories N2 gas is inserted, which has a large cross section for emission in the blue wave length region. Secondly, a larger signal strength is achieved by detecting the ionization products in an Ionization Profile Monitor (IPM). By applying an electric field all ionization products are accelerated toward a spatial resolving Micro-Channel Plate. The signal read-out can either be performed by observing the light from a phosphor screen behind the MCP or electronically by a wire array. Methods to achieve a high spatial resolution and a fast turn-by-turn readout capability are discussed. Even though various approaches at dif...

  14. E-perm radon monitors for determining waterborne concentrations of dissolved in radon 222Rn

    International Nuclear Information System (INIS)

    Jester, W.A.; Kotrappa, P.

    1989-01-01

    This paper describes a simple and relatively inexpensive method in which E-Perm radon monitors are used to determine the concentration of dissolved 222 Rn in drinking water. This procedure takes advantage of E-Perm's ability to accurately measure the integral radon exposure under conditions of high humidity. The method was evaluated against the liquid scintillation procedure recommended by the U.S. Environmental Protection Agency (EPA) and was found to give excellent agreement. An E-perm is an electret ion chamber that consists of a small chamber constructed from a conducting plastic and having an electret at its base and a filtered air inlet at the top. The technique described in this paper takes advantages of E-Perm's insensitivity to high humidity

  15. Portable spectrometer monitors inert gas shield in welding process

    Science.gov (United States)

    Grove, E. L.

    1967-01-01

    Portable spectrometer using photosensitive readouts, monitors the amount of oxygen and hydrogen in the inert gas shield of a tungsten-inert gas welding process. A fiber optic bundle transmits the light from the welding arc to the spectrometer.

  16. Membrane gas sensors for fermentation monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Mandenius, C F

    1987-12-01

    Results of a study on membrane gas sensors are presented to show their general applicability to fermentation monitoring of volatiles, such as alcohols, organic acids and aldehydes under various process and reactor conditions. Permeable silicone (Noax AB) and teflon (fluorcarbon AB) are tested as material for a gas sensor. The silicone tubing method is mainly used and ethanolic fermentation is performed in the study. Investigation is made to determine the dependence of the sensitivity of the sensors on the temperature, pH, concentration and other properties of fermentation liquid. The effect of temperature on the ethanol response is investigated in the temperature range of 7-50/sup 0/C to reveal that the response time decreases while the sensor's sensitivity increases with an increasing temperature. Comparison among methanol, ethyl acetate, acetaldehyde and ethanol is made with respect to the effect of their concentration on the sensitivity of a sensor. Results of a three-month measurement with the sensor immersed in fermentation liquid are compared with those of GC analysis to investigate the correlation between the sensor's sensitivity and GC analysis data. (11 figs, 17 refs)

  17. U.S. Geological Survey Noble Gas Laboratory’s standard operating procedures for the measurement of dissolved gas in water samples

    Science.gov (United States)

    Hunt, Andrew G.

    2015-08-12

    This report addresses the standard operating procedures used by the U.S. Geological Survey’s Noble Gas Laboratory in Denver, Colorado, U.S.A., for the measurement of dissolved gases (methane, nitrogen, oxygen, and carbon dioxide) and noble gas isotopes (helium-3, helium-4, neon-20, neon-21, neon-22, argon-36, argon-38, argon-40, kryton-84, krypton-86, xenon-103, and xenon-132) dissolved in water. A synopsis of the instrumentation used, procedures followed, calibration practices, standards used, and a quality assurance and quality control program is presented. The report outlines the day-to-day operation of the Residual Gas Analyzer Model 200, Mass Analyzer Products Model 215–50, and ultralow vacuum extraction line along with the sample handling procedures, noble gas extraction and purification, instrument measurement procedures, instrumental data acquisition, and calculations for the conversion of raw data from the mass spectrometer into noble gas concentrations per unit mass of water analyzed. Techniques for the preparation of artificial dissolved gas standards are detailed and coupled to a quality assurance and quality control program to present the accuracy of the procedures used in the laboratory.

  18. Noble gas atmospheric monitoring at reprocessing facilities

    International Nuclear Information System (INIS)

    Nakhleh, C.W.; Perry, R.T. Jr.; Poths, J.; Stanbro, W.D.; Wilson, W.B.; Fearey, B.L.

    1997-01-01

    The discovery in Iraq after the Gulf War of the existence of a large clandestine nuclear-weapon program has led to an across-the-board international effort, dubbed Programme 93+2, to improve the effectiveness and efficiency of International Atomic Energy Agency (IAEA) safeguards. One particularly significant potential change is the introduction of environmental monitoring (EM) techniques as an adjunct to traditional safeguards methods. Monitoring of stable noble gas (Kr, Xe) isotopic abundances at reprocessing plant stacks appears to be able to yield information on the burnup and type of the fuel being processed. To estimate the size of these signals, model calculations of the production of stable Kr, Xe nuclides in reactor fuel and the subsequent dilution of these nuclides in the plant stack are carried out for two case studies: reprocessing of PWR fuel with a burnup of 35 GWd/tU, and reprocessing of CAND fuel with a burnup of 1 GWd/tU. For each case, a maximum-likelihood analysis is used to determine the fuel burnup and type from the isotopic data

  19. In situ monitoring using Lab on Chip devices, with particular reference to dissolved silica.

    Science.gov (United States)

    Turner, G. S. C.; Loucaides, S.; Slavik, G. J.; Owsianka, D. R.; Beaton, A.; Nightingale, A.; Mowlem, M. C.

    2016-02-01

    In situ sensors are attractive alternatives to discrete sampling of natural waters, offering the potential for sustained long term monitoring and eliminating the need for sample handling. This can reduce sample contamination and degradation. In addition, sensors can be clustered into multi-parameter observatories and networked to provide both spatial and time series coverage. High resolution, low cost, and long term monitoring are the biggest advantages of these technologies to oceanographers. Microfluidic technology miniaturises bench-top assay systems into portable devices, known as a `lab on a chip' (LOC). The principle advantages of this technology are low power consumption, simplicity, speed, and stability without compromising on quality (accuracy, precision, selectivity, sensitivity). We have successfully demonstrated in situ sensors based on this technology for the measurement of pH, nitrate and nitrite. Dissolved silica (dSi) is an important macro-nutrient supporting a major fraction of oceanic primary production carried out by diatoms. The biogeochemical Si cycle is undergoing significant modifications due to human activities, which affects availability of dSi, and consequently primary production. Monitoring dSi concentrations is therefore critical in increasing our understanding of the biogeochemical Si cycle to predict and manage anthropogenic perturbations. The standard bench top air segmented flow technique utilising the reduction of silicomolybdic acid with spectrophotometric detection has been miniaturised into a LOC system; the target limit of detection is 1 nM, with ± 5% accuracy and 3% precision. Results from the assay optimisation are presented along with reagent shelf life to demonstrate the robustness of the chemistry. Laboratory trials of the sensor using ideal solutions and environmental samples in environmentally relevant conditions (temperature, pressure) are discussed, along with an overview of our current LOC analytical capabilities.

  20. Technology survey for real-time monitoring of plutonium in a vitrifier off-gas system

    International Nuclear Information System (INIS)

    Berg, J.M.; Veirs, D.K.

    1996-01-01

    We surveyed several promising measurement technologies for the real-time monitoring of plutonium in a vitrifier off-gas system. The vitrifier is being developed by Westinghouse Savannah River Corp. and will be used to demonstrate vitrification of plutonium dissolved in nitric acid for fissile material disposition. The risk of developing a criticality hazard in the off-gas processing equipment can be managed by using available measurement technologies. We identified several potential technologies and methods for detecting plutonium that are sensitive enough to detect the accumulation of a mass sufficient to form a criticality hazard. We recommend gross alpha-monitoring technologies as the most promising option for Westinghouse Savannah River Corp. to consider because that option appears to require the least additional development. We also recommend further consideration for several other technologies because they offer specific advantages and because gross alpha-monitoring could prove unsuitable when tested for this specific application

  1. Probing the regional distribution of pulmonary gas exchange through single-breath gas- and dissolved-phase 129Xe MR imaging.

    Science.gov (United States)

    Kaushik, S Sivaram; Freeman, Matthew S; Cleveland, Zackary I; Davies, John; Stiles, Jane; Virgincar, Rohan S; Robertson, Scott H; He, Mu; Kelly, Kevin T; Foster, W Michael; McAdams, H Page; Driehuys, Bastiaan

    2013-09-01

    Although some central aspects of pulmonary function (ventilation and perfusion) are known to be heterogeneous, the distribution of diffusive gas exchange remains poorly characterized. A solution is offered by hyperpolarized 129Xe magnetic resonance (MR) imaging, because this gas can be separately detected in the lung's air spaces and dissolved in its tissues. Early dissolved-phase 129Xe images exhibited intensity gradients that favored the dependent lung. To quantitatively corroborate this finding, we developed an interleaved, three-dimensional radial sequence to image the gaseous and dissolved 129Xe distributions in the same breath. These images were normalized and divided to calculate "129Xe gas-transfer" maps. We hypothesized that, for healthy volunteers, 129Xe gas-transfer maps would retain the previously observed posture-dependent gradients. This was tested in nine subjects: when the subjects were supine, 129Xe gas transfer exhibited a posterior-anterior gradient of -2.00 ± 0.74%/cm; when the subjects were prone, the gradient reversed to 1.94 ± 1.14%/cm (P exchange caused by differences in lung inflation and posture.

  2. Aerosol and iodine removal system for the dissolver off-gas in a large fuel reprocessing plant

    International Nuclear Information System (INIS)

    Furrer, J.; Wilhelm, J.G.; Jannakos, K.

    1979-01-01

    A newly developed filter combination for the dissolver off-gas in a reprocessing plant with a throughput of 1400 t/y of heavy metal is presented and single filter components are described. The design principle chosen provides for remote handling and direct disposal in waste drums of 200 l volume. The optimization of housings and filter units is studied on true scale components in the simulated dissolver off-gas of a test facility named PASSAT. This facility will be described. PASSAT will be also used for final testing of the SORPTEX process which is under development. Its concept is included in the paper. The design and function of the new multiway sorption filter providing for complete loading of the iodine sorption material and maintaining continuously high decontamznation factors will also be given. Removal efficiencies measured for aerosols and iodine in an existing reprocessing plant are indicated

  3. Suggested guidelines for gas emission monitoring at danish landfills

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Scheutz, Charlotte

    2015-01-01

    Landfill gas is produced on waste disposal sites receiving organic waste resulting in emission of methane. Regulation requires that the landfill gas is managed in order to reduce emissions, but very few suggestions exist to how the landfill gas management activities are monitored, what requirements...... to the ability of the landfill gas management to reduce the emission should be set up, and how criteria are developed for when the monitoring activities can be terminated. Monitoring procedures are suggested centred on a robust method for measuring the total methane emission from the site, and quantitative...

  4. Helium gas purity monitor based on low frequency acoustic resonance

    Science.gov (United States)

    Kasthurirengan, S.; Jacob, S.; Karunanithi, R.; Karthikeyan, A.

    1996-05-01

    Monitoring gas purity is an important aspect of gas recovery stations where air is usually one of the major impurities. Purity monitors of Katherometric type are commercially available for this purpose. Alternatively, we discuss here a helium gas purity monitor based on acoustic resonance of a cavity at audio frequencies. It measures the purity by monitoring the resonant frequency of a cylindrical cavity filled with the gas under test and excited by conventional telephone transducers fixed at the ends. The use of the latter simplifies the design considerably. The paper discusses the details of the resonant cavity and the electronic circuit along with temperature compensation. The unit has been calibrated with helium gas of known purities. The unit has a response time of the order of 10 minutes and measures the gas purity to an accuracy of 0.02%. The unit has been installed in our helium recovery system and is found to perform satisfactorily.

  5. The dynamics of dissolved oxygen concentration for water quality monitoring and assessment in polder ditches

    NARCIS (Netherlands)

    Veeningen, R.

    1983-01-01

    This study deals with the use of the dynamics of dissolved oxygen concentration for water quality assessment in polder ditches. The dynamics of the dissolved oxygen concentration, i.e. the temporal and spatial variations in a few polder ditches under a range of natural, pollution and management

  6. Plastic-bag radon gas monitor and survey results

    International Nuclear Information System (INIS)

    Torri, G.

    1990-01-01

    The Plastic-bag radon monitor used in the Italian National Survey is described. The choice of this radon gas sampler has been determined by the peculiarity of the italian environmental monitoring program, which is carried out by several different regional laboratories. Results obtained in the past using this radon monitoring device are also reported. (author). 8 refs, 7 figs

  7. Evaluation technology for burnup and generated amount of plutonium by measurement of Xenon isotopic ratio in dissolver off-gas at reprocessing facility (Joint research)

    International Nuclear Information System (INIS)

    Okano, Masanori; Kuno, Takehiko; Shirouzu, Hidetomo; Yamada, Keiji; Sakai, Toshio; Takahashi, Ichiro; Charlton, William S.; Wells, Cyndi A.; Hemberger, Philip H.

    2006-12-01

    The amount of Pu in the spent fuel was evaluated from Xe isotopic ratio in off-gas in reprocessing facility, is related to burnup. Six batches of dissolver off-gas (DOG) at spent fuel dissolution process were sampled from the main stack in Tokai Reprocessing Plant (TRP) during BWR fuel (approx. 30GWD/MTU) reprocessing campaign. Xenon isotopic ratio was determined with Gas Chromatography/Mass Spectrometry. Burnup and generated amount of Pu were evaluated with Noble Gas Environmental Monitoring Application code (NOVA), developed by Los Alamos National Laboratory. Inferred burnup evaluated by Xe isotopic measurements and NOVA were in good agreement with those of the declared burnup in the range from -3.8% to 7.1%. Also, the inferred amount of Pu in spent fuel was in good agreed with those of the declared amount of Pu calculated by ORIGEN code in the range from -0.9% to 4.7%. The evaluation technique is applicable for both burnup credit to achieve efficient criticality safety control and a new measurement method for safeguards inspection. (author)

  8. Field Tests of Real-time In-situ Dissolved CO2 Monitoring for CO2 Leakage Detection in Groundwater

    Science.gov (United States)

    Yang, C.; Zou, Y.; Delgado, J.; Guzman, N.; Pinedo, J.

    2016-12-01

    Groundwater monitoring for detecting CO2 leakage relies on groundwater sampling from water wells drilled into aquifers. Usually groundwater samples are required be collected periodically in field and analyzed in the laboratory. Obviously groundwater sampling is labor and cost-intensive for long-term monitoring of large areas. Potential damage and contamination of water samples during the sampling process can degrade accuracy, and intermittent monitoring may miss changes in the geochemical parameters of groundwater, and therefore signs of CO2 leakage. Real-time in-situ monitoring of geochemical parameters with chemical sensors may play an important role for CO2 leakage detection in groundwater at a geological carbon sequestration site. This study presents field demonstration of a real-time in situ monitoring system capable of covering large areas for detection of low levels of dissolved CO2 in groundwater and reliably differentiating natural variations of dissolved CO2 concentration from small changes resulting from leakage. The sand-alone system includes fully distributed fiber optic sensors for carbon dioxide detection with a unique sensor technology developed by Intelligent Optical Systems. The systems were deployed to the two research sites: the Brackenridge Field Laboratory where the aquifer is shallow at depths of 10-20 ft below surface and the Devine site where the aquifer is much deeper at depths of 140 to 150 ft. Groundwater samples were periodically collected from the water wells which were installed with the chemical sensors and further compared to the measurements of the chemical sensors. Our study shows that geochemical monitoring of dissolved CO2 with fiber optic sensors could provide reliable CO2 leakage signal detection in groundwater as long as CO2 leakage signals are stronger than background noises at the monitoring locations.

  9. Photonic crystal fiber modal interferometer with Pd/WO3 coating for real-time monitoring of dissolved hydrogen concentration in transformer oil.

    Science.gov (United States)

    Zhang, Ya-Nan; Wu, Qilu; Peng, Huijie; Zhao, Yong

    2016-12-01

    A highly-sensitive and temperature-robust photonic crystal fiber (PCF) modal interferometer coated with Pd/WO 3 film was fabricated and studied, aiming for real-time monitoring of dissolved hydrogen concentration in transformer oil. The sensor probe was fabricated by splicing two segments of a single mode fiber (SMF) with both ends of the PCF. Since the collapse of air holes in the PCF in the interfaces between SMF and PCF, a SMF-PCF-SMF interferometer structure was formed. The Pd/WO 3 film was fabricated by sol-gel method and coated on the surface of the PCF by dip-coating method. When the Pd/WO 3 film is exposed to hydrogen, both the length and cladding refractive index of the PCF would be changed, resulting in the resonant wavelength shift of the interferometer. Experimental results showed that the hydrogen measurement sensitivity of the proposed sensor can reach 0.109 pm/(μl/l) in the transformer oil, with the measurement range of 0-10 000 μl/l and response time less than 33 min. Besides, the proposed sensor was temperature-insensitive without any compensation process, easy to fabricate without any tapering, polishing, or etching process, low cost and quickly response without any oil-gas separation device. All these performances satisfy the actual need of real-time monitoring of dissolved hydrogen concentration in the transformer oil.

  10. Engineering considerations for corrosion monitoring of gas gathering pipeline systems

    Energy Technology Data Exchange (ETDEWEB)

    Braga, T.G.; Asperger, R.G.

    1987-01-01

    Proper corrosion monitoring of gas gathering pipelines requires a system review to determine the appropriate monitor locations and types of monitoring techniques. This paper develops and discusses a classification of conditions such as flow regime and gas composition. Also discussed are junction categories which, for corrosion monitoring, need to be considered from two points of view. The first is related to fluid flow in the line and the second is related corrosion inhibitor movement along the pipeline. The appropriate application of the various monitoring techniques such as coupons, hydrogen detectors, electrical resistance probe and linear polarization probes are discussed in relation to flow regime and gas composition. Problems caused by semi-conduction from iron sulfide are considered. Advantages and disadvantages of fluid gathering methods such as pots and flow-through drips are discussed in relation to their reliability as on-line monitoring locations.

  11. ANALYSIS OF DISSOLVED METHANE, ETHANE, AND ETHYLENE IN GROUND WATER BY A STANDARD GAS CHROMATOGRAPHIC TECHNIQUE

    Science.gov (United States)

    The measurement of dissolved gases such as methane, ethane, and ethylene in ground water is important in determining whether intrinsic bioremediation is occurring in a fuel- or solvent-contaminated aquifer. A simple procedure is described for the collection and subsequent analys...

  12. 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

  13. Carbon tetrachloride ERA soil-gas baseline monitoring

    International Nuclear Information System (INIS)

    Fancher, J.D.

    1994-01-01

    From December 1991 through December 1993, Westinghouse Hanford Company performed routine baseline monitoring of selected wells ad soil-gas points twice weekly in the 200 West Area of the Hanford Site. This work supported the carbon Tetrachloride Expedited Response Action (ERA) and provided a solid baseline of volatile organic compound (VOC) concentrations in wells and in the subsurface at the ERA site. As site remediation continues, comparisons to this baseline can be one means of measuring the success of carbon tetrachloride vapor extraction. This report contains observations of the patterns and trends associated with data obtained during soil-gas monitoring at the 200 West Area: Monitoring performed since late 1991 includes monitoring soil-gas probes ad wellheads for volatile organic compounds (VOCs). This report reflects monitoring data collected from December 1991 through December 1993

  14. 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

  15. On-line ultrasonic gas entrainment monitor

    International Nuclear Information System (INIS)

    Day, C.K.; Pedersen, H.N.

    1978-01-01

    Apparatus employing ultrasonic energy for detecting and measuring the quantity of gas bubbles present in liquids being transported through pipes is described. An ultrasonic transducer is positioned along the longitudinal axis of a fluid duct, oriented to transmit acoustic energy radially of the duct around the circumference of the enclosure walls. The back-reflected energy is received centrally of the duct and interpreted as a measure of gas entrainment. One embodiment employs a conical reflector to direct the transmitted acoustic energy radially of the duct and redirect the reflected energy back to the transducer for reception. A modified embodiment employs a cylindrical ultrasonic transducer for this purpose

  16. Disposal of Kr-85 separated from the dissolver off-gas of a reprocessing plant for LWR fuels

    International Nuclear Information System (INIS)

    Nommensen, O.

    1981-08-01

    The principle of the radiation protection to keep the radiation load of the population as low as possible requires the development of methods for retaining the radionuclide Krypton 85 seperated off the dissolver waste gas of future reprocessing plants for LWR-nuclear fuel elements. In a recommendation of the RSK the long-termed storage of the Kr-85 in a pressure gas bottle and the marine disposal we considered to be disposal methods low in risk. The present work develops a concept for both of the disposal methods and demonstrates their technical feasibility. The comparison of the cost estimations effected for both of the disposal methods shows that the costs related with the marine disposal of the pressure gas bottles amounting to 1.90 DM/kg of reprocessed U fall by the factor 10 below the costs that result from the surface storage of the bottles. In both cases was referred to a reprocessing capacity of 1400 t U/a corresponding to 50 GW installed nuclear power, thereby accumulating approximately 629 PBq (17 MCi) Kr-85 per year. Both concepts project the seperated radioactive inert gas to be filled in pressure gas bottles in a low temperature rectification plant. Each of the 85 bottles to be filled per year contains 7.4 PBq (200 kCi) Kr-85. (orig./HP) [de

  17. Shale gas impacts on groundwater resources: insights from monitoring a fracking site in Poland

    Science.gov (United States)

    Montcoudiol, Nelly; Isherwood, Catherine; Gunning, Andrew; Kelly, Thomas; Younger, Paul

    2017-04-01

    Exploitation of shale gas by hydraulic fracturing (fracking) is highly controversial and concerns have been raised regarding induced risks from this technique. The SHEER project, an EU Horizon 2020-funded project, is looking into developing best practice to understand, prevent and mitigate the potential short- and long-term environmental impacts and risks from shale gas exploration and exploitation. Three major potential impacts were identified: groundwater contamination, air pollution and induced seismicity. This presentation will deal with the hydrogeological aspect. As part of the SHEER project, four monitoring wells were installed at a shale gas exploration site in Northern Poland. They intercept the main drinking water aquifer located in Quaternary sediments. Baseline monitoring was carried out from mid-December 2015 to beginning of June 2016. Fracking operations occurred in two horizontal wells, in two stages, in June and July 2016. The monitoring has continued after fracking was completed, with site visits every 4-6 weeks. Collected data include measurements of groundwater level, conductivity and temperature at 15-minute intervals, frequent sampling for laboratory analyses and field measurements of groundwater physico-chemical parameters. Groundwater samples are analysed for a range of constituents including dissolved gases and isotopes. The presentation will focus on the interpretation of baseline monitoring data. The insights gained into the behaviour of the Quaternary aquifer will allow a greater perspective to be place on the initial project understanding draw from previous studies. Short-term impacts will also be discussed in comparison with the baseline monitoring results. The presentation will conclude with discussion of challenges regarding monitoring of shale gas fracking sites.

  18. Earthworms change the quantity and composition of dissolved organic carbon and reduce greenhouse gas emissions during composting.

    Science.gov (United States)

    Nigussie, Abebe; Bruun, Sander; de Neergaard, Andreas; Kuyper, Thomas W

    2017-04-01

    Dissolved organic carbon (DOC) has recently been proposed as an indicator of compost stability. We assessed the earthworms' effect on DOC content and composition during composting, and linked compost stability to greenhouse gas emissions and feeding ratio. Earthworms reduced total DOC content, indicating larger stability of vermicompost than of thermophilic compost. The concentrations of humic acid and fulvic acid were reduced by earthworms, whereas there was no significant effect on hydrophobic neutrals and hydrophilics. The humic acid fraction was depleted more quickly than the other compounds, indicating humic acid degradation during composting. The optimum feeding ratio decreased DOC content compared to the high feeding ratio. The lowest N 2 O emissions were also observed at the optimum feeding ratio. Our study confirmed the use of DOC content and composition as an indicator of compost stability and suggested that feeding ratio should be considered when assessing the earthworms' effect on stabilisation and greenhouse gas emissions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Rapid analysis of dissolved methane, ethylene, acetylene and ethane using partition coefficients and headspace-gas chromatography.

    Science.gov (United States)

    Lomond, Jasmine S; Tong, Anthony Z

    2011-01-01

    Analysis of dissolved methane, ethylene, acetylene, and ethane in water is crucial in evaluating anaerobic activity and investigating the sources of hydrocarbon contamination in aquatic environments. A rapid chromatographic method based on phase equilibrium between water and its headspace is developed for these analytes. The new method requires minimal sample preparation and no special apparatus except those associated with gas chromatography. Instead of Henry's Law used in similar previous studies, partition coefficients are used for the first time to calculate concentrations of dissolved hydrocarbon gases, which considerably simplifies the calculation involved. Partition coefficients are determined to be 128, 27.9, 1.28, and 96.3 at 30°C for methane, ethylene, acetylene, and ethane, respectively. It was discovered that the volume ratio of gas-to-liquid phase is critical to the accuracy of the measurements. The method performance can be readily improved by reducing the volume ratio of the two phases. Method validation shows less than 6% variation in accuracy and precision except at low levels of methane where interferences occur in ambient air. Method detection limits are determined to be in the low ng/L range for all analytes. The performance of the method is further tested using environmental samples collected from various sites in Nova Scotia.

  20. Novel microelectrode-based online system for monitoring N2O gas emissions during wastewater treatment.

    Science.gov (United States)

    Marques, Ricardo; Oehmen, Adrian; Pijuan, Maite

    2014-11-04

    Clark-type nitrous oxide (N2O) microelectrodes are commonly used for measuring dissolved N2O levels, but have not previously been tested for gas-phase applications, where the N2O emitted from wastewater systems can be directly quantified. In this study, N2O microelectrodes were tested and validated for online gas measurements, and assessed with respect to their temperature, gas flow, composition dependence, gas pressure, and humidity. An exponential correlation between temperature and sensor signal was found, whereas gas flow, composition, pressure, and humidity did not have any influence on the signal. Two of the sensors were tested at different N2O concentration ranges (0-422.3, 0-50, 0-10, and 0-2 ppmv N2O) and exhibited a linear response over each range. The N2O emission dynamics from two laboratory scale sequencing batch reactors performing ammonia or nitrite oxidation were also monitored using one of the microsensors and results were compared with two other analytical methods. Results show that N2O emissions were accurately described with these microelectrodes and support their application for assessing gaseous N2O emissions from wastewater treatment systems. Advantages of the sensors as compared to conventional measurement techniques include a wider quantification range of N2O fluxes, and a single measurement system that can assess both liquid and gas-phase N2O dynamics.

  1. Temperature monitoring of gas-cooled reactors

    International Nuclear Information System (INIS)

    Kaiser, G.E.

    1977-01-01

    The present paper deals with questions like : a) Why temperature monitoring in high-temperature reactors at all. b) How are the measuring positions arranged and how are the measurements designed. c) What technique of temperature measurement is applied. (RW) [de

  2. The isotopic chemical and dissolved gas concentrations in groundwater near Venterstad, Cape Province

    International Nuclear Information System (INIS)

    Vogel, J.C.; Talma, A.S.; Heaton, T.H.E.

    1980-01-01

    Groundwater was collected for a multi parameter investigation from 27 boreholes within a radius of 120 km from Venterstad (Cape Province). The samples were analysed for the isotopes carbon-14, carbon-13, oxygen-18, tritium and radon-222, for the dissolved gases nitrogen, oxygen, argon, methane and helium and for the major ionic species. These data, with those collected during previous investigations of the flooding of the Orange Fish tunnel, are used to discuss the geohydrology of the area. Three water types of different origin were delineated

  3. Reactor cover gas monitoring at the Fast Flux Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Bechtold, R A; Holt, F E; Meadows, G E; Schenter, R E [Westinghouse Hanford Company, Richland, WA (United States)

    1987-07-01

    The Fast Flux Test Facility (FFTF) is a 400 megawatt (thermal) sodium cooled reactor designed for irradiation testing of fuels, materials and components for LMRs. It is operated by the Westinghouse Hanford Company for the U. S. Department of Energy on the government-owned Hanford reservation near Richland, Washington. The first 100 day operating cycle began in April 1982 and the eighth operating cycle was completed In July 1986. Argon is used as the cover gas for all sodium systems at the plant. A program for cover gas monitoring has been in effect since the start of sodium fill in 1978. The argon is supplied to the FFTF by a liquid argon Dewar System and used without further purification. A liquid argon Dewar system provides the large volume of inert gas required for operation of the FFTF. The gas is used as received and is not recycled. Low concentrations of krypton and xenon in the argon supply are essential to preclude interference with the gas tag system. Gas chromatography has been valuable for detection of inadvertent air in leakage during refueling operations. A temporary system is installed over the reactor during outages to prevent oxide formation in the sodium vapor traps upstream from the on line gas chromatograph. On line gas monitoring by gamma spectrometry and grab sampling with GTSTs has been successful for the identification of numerous radioactive gas releases from creep capsule experiments as well as 9 fuel pin ruptures. A redundant fission gas monitoring system has been installed to insure constant surveillance of the reactor cover gas.

  4. Monitoring of noble gas radioisotopes in nuclear power plant effluents

    International Nuclear Information System (INIS)

    Kabat, M.J.

    1985-01-01

    Monitoring of gaseous radionuclides in the effluents of nuclear facilities is an essential requirement in effluent management programs. Since there is no practical way of removing noble gas radioisotopes from air at release pathways, their accurate monitoring is essential for providing appropriate environmental protection. Emitted γ dose-rate is the limiting factor for concentration-time integral of noble gas in gaseous effluents of reactor facilities. The external exposure to the public from a semi-infinite cloud is directly proportional to both the noble gas isotope concentration and the integrated γ energy per disintegration. Both can be directly measured in gaseous effluent pathways with a suitable detector. The capability of NaI(T1), CaF 2 (Eu) and plastic scintillation detectors to measure the γ-Ci.MeV content of noble gas releases was experimentally evaluated. The combination of CaF 2 (Eu) detector in a pressurized through-flow chamber, with a charge integrating scaler well complied with both γ energy response and detection sensitivity requirements. Noble gas source terms and effluent monitoring criteria are discussed, theoretical and experimental results are presented and a practical, on-line noble gas monitoring system is described

  5. Miniaturized Planar Room Temperature Ionic Liquid Electrochemical Gas Sensor for Rapid Multiple Gas Pollutants Monitoring.

    Science.gov (United States)

    Wan, Hao; Yin, Heyu; Lin, Lu; Zeng, Xiangqun; Mason, Andrew J

    2018-02-01

    The growing impact of airborne pollutants and explosive gases on human health and occupational safety has escalated the demand of sensors to monitor hazardous gases. This paper presents a new miniaturized planar electrochemical gas sensor for rapid measurement of multiple gaseous hazards. The gas sensor features a porous polytetrafluoroethylene substrate that enables fast gas diffusion and room temperature ionic liquid as the electrolyte. Metal sputtering was utilized for platinum electrodes fabrication to enhance adhesion between the electrodes and the substrate. Together with carefully selected electrochemical methods, the miniaturized gas sensor is capable of measuring multiple gases including oxygen, methane, ozone and sulfur dioxide that are important to human health and safety. Compared to its manually-assembled Clark-cell predecessor, this sensor provides better sensitivity, linearity and repeatability, as validated for oxygen monitoring. With solid performance, fast response and miniaturized size, this sensor is promising for deployment in wearable devices for real-time point-of-exposure gas pollutant monitoring.

  6. Separation of the fission product noble gases krypton and xenon from dissolver off-gas in reprocessing HTGR-fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bohnenstingl, J.; Djoa, S. H.; Laser, M.; Mastera, S.; Merz, E.; Morschl, P.

    1976-04-15

    This paper describes a process developed for the retainment and separation of volatile (3H, 129 +131I) and gaseous (85Kr, Xe) fission products from the off-gas produced during dissolution of HTGR-fuel. To prevent unnecessary dilution of liberated noble gases by surrounding atmosphere, a helium purge-gas cycle is applied to enable a coarse fractionating of krypton and xenon by cold-trapping at about 80 deg K after precleaning the gas stream. The process consists of the following steps: deposition of droplets and solid aerosols; chemisorption of iodine on silver impregnated silica gel; catalytic removal of nitrogen oxides and oxygen; drying of the process gas stream; final filtering of abraded solids; deposition of xenon in solid form at 80 deg K and low subpressure; deposition of krypton in solid form at 80 deg K after compression to about 6 bar; decontamination of 85krypton-containing xenon by batch distillation for eventual industrial utilization; and removal of nitrogen and argon enrichment during continuous operation in the purge-gas stream by inleaking air with charcoal. A continuously operating dissolver vessel, closed to the surrounding atmosphere, yields a very high content of noble gases, e.g., 0.35 vol % krypton and 2.0 vol % xenon. The presented off-gas treatment unit is operated in cold runs with 1/3 of the full capacity and can treat about 1 m3 STP/h helium, corresponding to a quantity of about 10,000 MW(e) HTGR-fuel reprocessing plant.

  7. Separation of the fission product noble gases krypton and xenon from dissolver off-gas in reprocessing HTGR-fuel

    International Nuclear Information System (INIS)

    Bohnenstingl, J.; Djoa, S.H.; Laser, M.; Mastera, S.; Merz, E.; Morschl, P.

    1976-01-01

    This paper describes a process developed for the retainment and separation of volatile ( 3 H, 129+131 I) and gaseous ( 85 Kr, Xe) fission products from the off-gas produced during dissolution of HTGR-fuel. To prevent unnecessary dilution of liberated noble gases by surrounding atmosphere, a helium purge-gas cycle is applied to enable a coarse fractionating of krypton and xenon by cold-trapping at about 80 0 K after precleaning the gas stream. The process consists of the following steps: deposition of droplets and solid aerosols; chemisorption of iodine on silver impregnated silica gel; catalytic removal of nitrogen oxides and oxygen; drying of the process gas stream; final filtering of abraded solids; deposition of xenon in solid form at 80 0 K and low subpressure; deposition of krypton in solid form at 80 0 K after compression to about 6 bar; decontamination of 85 Kr-containing xenon by batch distillation for eventual industrial utilization; and removal of nitrogen and argon enrichment during continuous operation in the purge-gas stream by inleaking air with charcoal. A continuously operating dissolver vessel, closed to the surrounding atmosphere, yields a very high content of noble gases, i.e., 0.35 vol % krypton and 2.0 vol % xenon. The presented off-gas treatment unit is operated in cold runs with 1 / 3 of the full capacity and can treat about 1 m 3 STP/h helium, corresponding to a quantity of about 10,000 MW/sub e/ HTGR-fuel reprocessing plant

  8. Pilot plant development for adsorptive krypton separation from dissolver off-gas

    International Nuclear Information System (INIS)

    Ringel, H.; Printz, R.

    1987-01-01

    In view of hot cell application a separation process was investigated for the retention of Kr-85 from gaseous effluents. In the flow sheet only adsorption beds are applied. The most efficient process scheme is adsorption of the noble gas on activated charcoal and thereafter separation of the coadsorbed gas species like N 2 , O 2 , Xe and CO 2 from the krypton by gas chromatography. Adsorption is at normal pressure and low temperatures of up to -160 0 C, whereas desorption is at elevated temperatures and under helium purge. Influences on the process operation like off-gas composition, adsorption temperatures and adsorbent are experimentally investigated, as well as the behavior of trace impurities in the adsorption columns. On the basis of pilot plant operation the main components for a full scale facility are being designed

  9. Gas transport below artificial recharge ponds: insights from dissolved noble gases and a dual gas (SF6 and 3He) tracer experiment.

    Science.gov (United States)

    Clark, Jordan F; Hudson, G Bryant; Avisar, Dror

    2005-06-01

    A dual gas tracer experiment using sulfur hexafluoride (SF6) and an isotope of helium (3He) and measurements of dissolved noble gases was performed at the El Rio spreading grounds to examine gas transport and trapped air below an artificial recharge pond with a very high recharge rate (approximately 4 m day(-1)). Noble gas concentrations in the groundwater were greater than in surface water due to excess air formation showing that trapped air exists below the pond. Breakthrough curves of SF6 and 3He at two nearby production wells were very similar and suggest that nonequilibrium gas transfer was occurring between the percolating water and the trapped air. At one well screened between 50 and 90 m below ground, both tracers were detected after 5 days and reached a maximum at approximately 24 days. Despite the potential dilution caused by mixing within the production well, the maximum concentration was approximately 25% of the mean pond concentration. More than 50% of the SF6 recharged was recovered by the production wells during the 18 month long experiment. Our results demonstrate that at artificial recharge sites with high infiltration rates and moderately deep water tables, transport times between recharge locations and wells determined with gas tracer experiments are reliable.

  10. Fuel rod puncturing and fission gas monitoring system examination techniques

    International Nuclear Information System (INIS)

    Song, Woong Sup

    1999-02-01

    Fission gas products accumulated in irradiated fuel rod is 1-2 cm 3 in CANDU and 40-50 cm 3 in PWR fuel rod. Fuel rod puncturing and fission gas monitoring system can be used for both CANDU and PWR fuel rod. This system comprises puncturing device located at in cell part and monitoring device located at out cell part. The system has computerized 9 modes and can calculate both void volume and mass volume only single puncturing. This report describes techniques and procedure for operating fuel rod puncturing and gas monitoring system which can be play an important role in successful operation of the devices. Results obtained from the analysis can give more influence over design for fuel rods. (Author). 6 refs., 9 figs

  11. Infrared spectroscopy for monitoring gas hydrates in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Dobbs, G.T.; Luzinova, Y.; Mizaikoff, B. [Georgia Inst. of Technology, Atlanta, GA (United States). School of Chemistry and Biochemistry; Raichlin, Y.; Katzir, A. [Tel-Aviv Univ., Tel-Aviv (Israel). Shool of Physics and Astronomy

    2008-07-01

    This paper introduced the first principles for monitoring gas hydrate formation and dissociation in aqueous solution by evaluating state-responsive infrared (IR) absorption features of water with fiberoptic evanescent field spectroscopy. A first order linear functional relationship was also derived according to Lambert Beer's law in order to quantify the percentage gas hydrate within the volume of water probed via the evanescent field. In addition, spectroscopic studies evaluating seafloor sediments collected from a gas hydrate site in the Gulf of Mexico revealed minimal spectral interferences from sediment matrix components. As such, evanescent field sensing strategies were established as a promising perspective for monitoring the dynamics of gas hydrates in oceanic environments. 21 refs., 5 figs.

  12. Real-time trend monitoring of gas compressor stations

    Energy Technology Data Exchange (ETDEWEB)

    Van Hardeveld, T. (Nova, an Alberta Corp., AB (Canada))

    1991-02-01

    The authors' company has developed a machinery health monitoring system (MHealth) for short-term and long-term historical trending and analysis of data from its 40 gas compressor stations. The author discusses the benefits of real-time trending in troubleshooting operations, in preventative maintenance scheduling and cites specific applications in the startup operations of several new gas compressor/centrifugal compressor units.

  13. Cryogenic separation of krypton and xenon from dissolver off-gas

    Energy Technology Data Exchange (ETDEWEB)

    Bohnenstingl, J.; Heidendael, M.; Laser, M.; Mastera, S.; Merz, E.

    1976-03-15

    Although the release of fission product noble gas Kr-85 has not posed a health problem to date, a process is being developed for the removal and storage of fission product noble gases from dissolution process stream of fuel reprocessing. The separation process described for noble gas in air being proved in semi-technical scale includes cryogenic distillation and consists of the following steps: (1) removal of 129 +131iodine on silver-coated silica gel; (2) deposition of particulate materials by HEPA-filters; (3) elimination of O2 and NOx by catalytic conversion with H2/ to N2 and H2O; (4) drying of the gas stream with molecular sieve; (5) deposition of xenon in solid form at about 80 K, while the remaining gas components are liquified; (6) enrichment of Kr by low temperature distillation of liquid-gas mixture; (7) withdrawal of the highly enriched Kr-fraction at the bottom of the still to be bottled in pressurized steel cylinders for final disposal; and (8) purification of Kr-85 contaminated Xe for further industrial reuse by batch distillation.

  14. Experimental study on engine gas-path component fault monitoring using exhaust gas electrostatic signal

    International Nuclear Information System (INIS)

    Sun, Jianzhong; Zuo, Hongfu; Liu, Pengpeng; Wen, Zhenhua

    2013-01-01

    This paper presents the recent development in engine gas-path components health monitoring using electrostatic sensors in combination with signal-processing techniques. Two ground-based engine electrostatic monitoring experiments are reported and the exhaust gas electrostatic monitoring signal-based fault-detection method is proposed. It is found that the water washing, oil leakage and combustor linear cracking result in an increase in the activity level of the electrostatic monitoring signal, which can be detected by the electrostatic monitoring system. For on-line health monitoring of the gas-path components, a baseline model-based fault-detection method is proposed and the multivariate state estimation technique is used to establish the baseline model for the electrostatic monitoring signal. The method is applied to a data set from a turbo-shaft engine electrostatic monitoring experiment. The results of the case study show that the system with the developed method is capable of detecting the gas-path component fault in an on-line fashion. (paper)

  15. Tritium-gas/water-vapor monitor. Tests and evaluation

    International Nuclear Information System (INIS)

    Jalbert, R.A.

    1982-07-01

    A tritium gas/water-vapor monitor was designed and built by the Health Physics Group at the Los Alamos National Laboratory. In its prototype configuration, the monitor took the shape of two separate instruments: a (total) tritium monitor and a water-vapor monitor. Both instruments were tested and evaluated. The tests of the (total) tritium monitor, basically an improved version of the standard flow-through ion-chamber instrument, are briefly reported here and more completely elsewhere. The tests of the water-vapor monitor indicated that the novel approach used to condense water vapor for scintillation counting has a number of serious drawbacks and that further development of the instrument is unwarranted

  16. Modular design of a reprocessing plant dissolver off-gas system. Variations, flexibility and stage of development

    International Nuclear Information System (INIS)

    Henrich, E.; Huefner, R.

    1984-01-01

    Simple and economic control of the volatile radionuclides in a reprocessing plant requires two equally important prerequisites: suitable processing in the plant head-end and reliable operation of the dissolver off-gas (DOG) purification system. A small number of DOG purification modules was selected from various alternatives. The major selection criteria are removal efficiency, simplicity, convenient operating conditions and flexibility that provide compatibility with other off-gas treatment steps, subsequent waste treatment and different processing modes in the head-end. The behaviour of noxious materials was investigated in nitric acid off-gas scrubbers of different design and for a wide range of operating modes and conditions. A concentration range of nitric acid from very dilute to hyperazeotropic concentrations and a temperature range from -55 deg. C to above room temperature as well as the use of hydrogen peroxide were studied on an engineering scale. Nitrous gases and iodine can be removed to the trace level at special operating modes. Aerosol and iodine filters are discussed briefly. A selective absorption process using CF 2 Cl 2 solvent for noble gas and 14 C removal was developed on a laboratory scale. It operates at low temperatures and atmospheric pressure. Xe and Kr were separated using two absorption columns. Pilot-plant scale noble gas scrubbers are under construction and are being integrated into the existing test facility. A series of process steps has been chosen for integrated process demonstration runs on an engineering scale. The integrated DOG system consists of several scrubbers and filters operating at atmospheric pressure. The temperature decreases stepwise, without producing large changes in the opposite direction, providing compatibility within the process train

  17. Influence of dissolved gas and temperature on the light yield of new liquid scintillators

    CERN Document Server

    Buontempo, S; Golovkin, S V; Martellotti, G; Medvedkov, A M; Penso, G; Soloviev, A S; Vasilchenko, V G

    1999-01-01

    Sixteen new liquid scintillators, emitting green light, were studied. They are based on four solvents combined with four dopants. The influence of different gas atmospheres was studied. In particular it was shown that by keeping these liquid scintillators in vacuum or in a neutral gas, the light yield increases up to 32~\\% at 20 $^{\\circ}$C and for the best solvent-dopant combinations. The dependance of the light yield on temperature was also studied for these scintillators. In the 20--60 $^{\\circ}$C interval, some exhibit a light yield variation of $\\sim$ 3 \\% which is smaller than that of the NE 102A plastic scintillator.

  18. Earthworms change the quantity and composition of dissolved organic carbon and reduce greenhouse gas emissions during composting

    DEFF Research Database (Denmark)

    Nigatu, Abebe Nigussie; Bruun, Sander; de Neergaard, Andreas

    2017-01-01

    Dissolved organic carbon (DOC) has recently been proposed as an indicator of compost stability. We assessed the earthworms' effect on DOC content and composition during composting, and linked compost stability to greenhouse gas emissions and feeding ratio. Earthworms reduced total DOC content......, indicating larger stability of vermicompost than of thermophilic compost. The concentrations of humic acid and fulvic acid were reduced by earthworms, whereas there was no significant effect on hydrophobic neutrals and hydrophilics. The humic acid fraction was depleted more quickly than the other compounds......, indicating humic acid degradation during composting. The optimum feeding ratio decreased DOC content compared to the high feeding ratio. The lowest N2O emissions were also observed at the optimum feeding ratio. Our study confirmed the use of DOC content and composition as an indicator of compost stability...

  19. Monitoring of energy efficiency of technological modes of gas transport using modern gas-turbine equipment

    Science.gov (United States)

    Golik, V. V.; Zemenkova, M. Yu; Shipovalov, A. N.; Akulov, K. A.

    2018-05-01

    The paper presents calculations and an example of energy efficiency justification of the regimes of the equipment used. The engineering design of the gas pipeline in the part of monitoring the energy efficiency of a gas compressor unit (GCU) is considered. The results of the GCU characteristics and its components evaluation are described. The evaluation results of the energy efficiency indicators of the gas pipeline are presented. As an example of the result of the analysis, it is proposed to use gas compressor unit GCU-32 "Ladoga" because of its efficiency and cost effectiveness, in comparison with analogues.

  20. Design of instrument for monitoring nuclear radiation and baneful gas

    International Nuclear Information System (INIS)

    Xiong Jianping; Chen Jun; Zhu Wenkai

    2006-01-01

    Counters and ionization chambers are applied to sensors, and microprocessor based on ARM IP is applied to center controller in the instrument. It is achieved to monitor nuclear radiation and baneful gas in an instrument. The instrument is capable of LCD displaying, menu operating and speech alarming. (authors)

  1. The first experience with LHC beam gas ionization monitor

    CERN Document Server

    Sapinski, M; Dehning, B; Guerrero, A; Patecki, M; Versteegen, R

    2012-01-01

    The Beam Gas Ionization Monitors (BGI) are used to measure beam emittance on LHC. This paper describes the detectors and their operation and discusses the issues met during the commissioning. It also discusses the various calibration procedures used to correct for non-uniformity of Multi-Channel plates and to correct the beam size for effects affecting the electron trajectory after ionization.

  2. Specific radiological monitoring (SRM) in oil and gas production platforms

    International Nuclear Information System (INIS)

    Hairul Nizam Idris, Syed Asraf Fahlawi Wafa S.M Ghazi and Fadzley Izwan Abd Manaf

    2007-01-01

    Technologically enhanced naturally occurring radioactive materials (TENORM) are present in components of both oil and natural gas production facilities. TENORM can be associated with the presence of crude oil, produced water and natural gas. The radiation exposure pathways to the workers in oil and gas production are similar to those in the uranium and heavy mineral sand mining and processing industry. This paper work provides a short review on the Specific Radiological Monitoring (SRM) program were carried out at oil and gas platforms in the east cost of Peninsular Malaysia. The objective of this paper work is to observe the monitoring parameters levels and to evaluate whether these levels are exceeding the limits set by Atomic Energy Licensing Board (AELB). The monitoring results showed that the surface contamination, airborne contamination and concentration of radon and thoron are well below the set limit stipulated in LEM/TEK/30 SEM.2, except for external radiation and radioactivity concentration of sludge and scales. About 2 (2.35%) from the 85 external radiation measurements performed were found above the permissible limit. While about 11 (36.6%) and 7 (23.3%) of the 30 collected sludge and scales samples were found containing higher Ra-226 and Ra-228, respectively, than the mean concentrations in normal soils of Peninsular Malaysia. In general, it can be concluded that a few of oil and gas production platform are producing TENORM. (Author)

  3. Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

    International Nuclear Information System (INIS)

    Abernethy, Cary S; Amidan, Brett G

    2001-01-01

    The objective of this study was to examine the relative importance of pressure changes as a source of turbine-passage injury and mortality. Specific tests were designed to quantify the response of fish to rapid pressure changes typical of turbine passage, with and without the complication of the fish being acclimated to gas supersaturated water. We investigated the responses of rainbow trout (Oncorhynchus mykiss), chinook salmon (O. tshawytscha), and bluegill sunfish (Lepomis macrochirus) to these two stresses, both singly and in combination

  4. 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

  5. Hydrogeochemical processes controlling water and dissolved gas chemistry at the Accesa sinkhole (southern Tuscany, central Italy

    Directory of Open Access Journals (Sweden)

    Franco Tassi

    2014-05-01

    Full Text Available The 38.5 m deep Lake Accesa is a sinkhole located in southern Tuscany (Italy that shows a peculiar water composition, being characterized by relatively high total dissolved solids (TDS values (2 g L-1 and a Ca(Mg-SO4 geochemical facies. The presence of significant amounts of extra-atmospheric gases (CO2 and CH4, which increase their concentrations with depth, is also recognized. These chemical features, mimicking those commonly shown by volcanic lakes fed by hydrothermal-magmatic reservoirs, are consistent with those of mineral springs emerging in the study area whose chemistry is produced by the interaction of meteoric-derived waters with Mesozoic carbonates and Triassic evaporites. Although the lake has a pronounced thermocline, water chemistry does not show significant changes along the vertical profile. Lake water balance calculations demonstrate that Lake Accesa has >90% of its water supply from sublacustrine springs whose subterranean pathways are controlled by the local structural assessment that likely determined the sinking event, the resulting funnel-shape being then filled by the Accesa waters. Such a huge water inflow from the lake bottom (~9·106 m3 yr-1 feeds the lake effluent (Bruna River and promotes the formation of water currents, which are able to prevent the establishment of a vertical density gradient. Consequently, a continuous mixing along the whole vertical water column is established. Changes of the drainage system by the deep-originated waters in the nearby former mining district have strongly affected the outflow rates of the local mineral springs; thus, future intervention associated with the ongoing remediation activities should carefully be evaluated to preserve the peculiar chemical features of Lake Accesa.

  6. Remote real-time monitoring of subsurface landfill gas migration.

    Science.gov (United States)

    Fay, Cormac; Doherty, Aiden R; Beirne, Stephen; Collins, Fiachra; Foley, Colum; Healy, John; Kiernan, Breda M; Lee, Hyowon; Maher, Damien; Orpen, Dylan; Phelan, Thomas; Qiu, Zhengwei; Zhang, Kirk; Gurrin, Cathal; Corcoran, Brian; O'Connor, Noel E; Smeaton, Alan F; Diamond, Dermot

    2011-01-01

    The cost of monitoring greenhouse gas emissions from landfill sites is of major concern for regulatory authorities. The current monitoring procedure is recognised as labour intensive, requiring agency inspectors to physically travel to perimeter borehole wells in rough terrain and manually measure gas concentration levels with expensive hand-held instrumentation. In this article we present a cost-effective and efficient system for remotely monitoring landfill subsurface migration of methane and carbon dioxide concentration levels. Based purely on an autonomous sensing architecture, the proposed sensing platform was capable of performing complex analytical measurements in situ and successfully communicating the data remotely to a cloud database. A web tool was developed to present the sensed data to relevant stakeholders. We report our experiences in deploying such an approach in the field over a period of approximately 16 months.

  7. Using High Spatio-Temporal Optical Remote Sensing to Monitor Dissolved Organic Carbon in the Arctic River Yenisei

    Directory of Open Access Journals (Sweden)

    Pierre-Alexis Herrault

    2016-09-01

    Full Text Available In Arctic regions, a major concern is the release of carbon from melting permafrost that could greatly exceed current human carbon emissions. Arctic rivers drain these organic-rich watersheds (Ob, Lena, Yenisei, Mackenzie, Yukon but field measurements at the outlets of these great Arctic rivers are constrained by limited accessibility of sampling sites. In particular, the highest dissolved organic carbon (DOC fluxes are observed throughout the ice breakup period that occurs over a short two to three-week period in late May or early June during the snowmelt-generated peak flow. The colored fraction of dissolved organic carbon (DOC which absorbs UV and visible light is designed as chromophoric dissolved organic matter (CDOM. It is highly correlated to DOC in large arctic rivers and streams, allowing for remote sensing to monitor DOC concentrations from satellite imagery. High temporal and spatial resolutions remote sensing tools are highly relevant for the study of DOC fluxes in a large Arctic river. The high temporal resolution allows for correctly assessing this highly dynamic process, especially the spring freshet event (a few weeks in May. The high spatial resolution allows for assessing the spatial variability within the stream and quantifying DOC transfer during the ice break period when the access to the river is almost impossible. In this study, we develop a CDOM retrieval algorithm at a high spatial and a high temporal resolution in the Yenisei River. We used extensive DOC and DOM spectral absorbance datasets from 2014 and 2015. Twelve SPOT5 (Take5 and Landsat 8 (OLI images from 2014 and 2015 were examined for this investigation. Relationships between CDOM and spectral variables were explored using linear models (LM. Results demonstrated the capacity of a CDOM algorithm retrieval to monitor DOC fluxes in the Yenisei River during a whole open water season with a special focus on the peak flow period. Overall, future Sentinel2/Landsat8

  8. Monitoring environmental effects of shale gas exploitation at Wysin in Poland.

    Science.gov (United States)

    Lasocki, Stanislaw; Mirek, Janusz; Bialon, Wojciech; Cielesta, Szymon; Lasak, Mateusz; Cesca, Simone; Lopez Comino, Jose Angel; Dahm, Torsten; Scarpa, Roberto; Gunning, Andrew; Montcoudiol, Nelly; Isherwood, Catherine; Jaroslawski, Janusz; Guzikowski, Jakub

    2017-04-01

    Environmental effects of shale gas exploration and exploitation are extensively studied in the framework of "Shale Gas Exploration and Exploitation Induced Risks" project (SHEER, H2020-LCE 16-2014-1). One of the main component of this study is on-site monitoring of the effects at Wysin shale-gas play of Polish Oil and Gas Company in Poland. This includes monitoring of seismicity and water and air quality. Surface seismic monitoring network consists of 6 surface broadband (BB) seismometers and 25 surface short-period (SP) seismometers The SPs are assembled into three small aperture arrays with 9, 8 and 8 stations, respectively, distributed in a triangle geometry at a distance of about 2-4 km from the hydrofracturing rig. Each array is complemented with one BB station. The three remaining BBs are located up to about 5 km from the rig. In addition 3 borehole broadband seismometers are located in three shallow boreholes. The groundwater monitoring makes use of four wells, which reach a main underground water reservoir. Three complementary datasets are collected: continuous monitoring of borehole data, laboratory analyses of water samples and field monitoring of water quality parameters. The continuous monitoring makes use of down-hole probes, which have been installed in each borehole. The probes record absolute pressure, temperature and electrical conductivity. In addition, a barometric probe has been installed above ground to record atmospheric pressure in order to allow conversion of absolute pressure to a water level. After collection, water samples are sent to an accredited laboratory for analysis. The field monitoring is undertaken during the sampling visits. Whilst the borehole is being purged, physico-chemical parameters are monitored using a multi-parameter probe. This measures and records temperature, specific conductivity, pH, dissolved oxygen and oxidation-reduction potential within the water. Hydrocarbon gas content within the water is below detection

  9. Extreme dissolved oxygen variability in urbanised tropical wetlands: The need for detailed monitoring to protect nursery ground values

    Science.gov (United States)

    Dubuc, Alexia; Waltham, Nathan; Malerba, Martino; Sheaves, Marcus

    2017-11-01

    Little is known about levels of dissolved oxygen fish are exposed to daily in typical urbanised tropical wetlands found along the Great Barrier Reef coastline. This study investigates diel dissolved oxygen (DO) dynamics in one of these typical urbanised wetlands, in tropical North Queensland, Australia. High frequency data loggers (DO, temperature, depth) were deployed for several days over the summer months in different tidal pools and channels that fish use as temporal or permanent refuges. DO was extremely variable over a 24 h cycle, and across the small-scale wetland. The high spatial and temporal DO variability measured was affected by time of day and tidal factors, namely water depth, tidal range and tidal direction (flood vs ebb). For the duration of the logging time, DO was mainly above the adopted threshold for hypoxia (50% saturation), however, for around 11% of the time, and on almost every logging day, DO values fell below the threshold, including a severe hypoxic event (nursery ground value. There is a substantial discontinuity between the recommended DO values in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality and the values observed in this wetland, highlighting the limited value of these guidelines for management purposes. Local and regional high frequency data monitoring programs, in conjunction with local exposure risk studies are needed to underpin the development of the management that will ensure the sustainability of coastal wetlands.

  10. Silicon microring refractometric sensor for atmospheric CO(2) gas monitoring.

    Science.gov (United States)

    Mi, Guangcan; Horvath, Cameron; Aktary, Mirwais; Van, Vien

    2016-01-25

    We report a silicon photonic refractometric CO(2) gas sensor operating at room temperature and capable of detecting CO(2) gas at atmospheric concentrations. The sensor uses a novel functional material layer based on a guanidine polymer derivative, which is shown to exhibit reversible refractive index change upon absorption and release of CO(2) gas molecules, and does not require the presence of humidity to operate. By functionalizing a silicon microring resonator with a thin layer of the polymer, we could detect CO(2) gas concentrations in the 0-500ppm range with a sensitivity of 6 × 10(-9) RIU/ppm and a detection limit of 20ppm. The microring transducer provides a potential integrated solution in the development of low-cost and compact CO(2) sensors that can be deployed as part of a sensor network for accurate environmental monitoring of greenhouse gases.

  11. A Gas Chromatographic Method for the Determination of Bicarbonate and Dissolved Gases

    Directory of Open Access Journals (Sweden)

    John H. Loughrin

    2017-11-01

    Full Text Available A gas chromatographic method for the rapid determination of aqueous carbon dioxide and its speciation into solvated carbon dioxide and bicarbonate is presented. One-half mL samples are injected through a rubber septum into 20-mL vials that are filled with 9.5 mL of 0.1 N HCl. A one mL portion of the headspace is withdrawn and injected onto a gas chromatograph equipped with a thermal conductivity detector. Using the dimensionless Henry's constant for carbon dioxide and an adaptation of the Henderson-Hasselbalch equation, carbon dioxide in the samples can be categorized among solvated, bicarbonate, and carbonate forms. Natural water samples as well as wastewater from a municipal sewage treatment plant and a swine rearing operation were analyzed by this method and the results compared favorably to those obtained by titration. Samples stored for up to 5 weeks showed no significant changes in carbon dioxide concentrations. In addition, using flame ionization and electron capture detectors, methane and nitrous oxide concentrations in the samples were also measured.

  12. Air-sea gas transfer in a shallow, flowing and coastal environment estimated by dissolved inorganic carbon and dissolved oxygen analyses

    Digital Repository Service at National Institute of Oceanography (India)

    Abe, O.; Watanabe, A.; Sarma, V.V.S.S.; Matsu, Y.; Yamano, H.; Yoshida, N.; Saino, T.

    crest and an outflow through a prominent 8 channel, whereas southern wind conditions this pattern is weakened or disturbed 9 (Yamano et al., 1998). Thus, during northern to northeastern winds, metabolic activities 10 with respect to primary production...). Dissolved oxygen was almost less than saturation during the observation period, 16 except on 8 March (Fig. 3f), when the daytime concentration exceeded saturation level 17 due to the increase of net productivity associated with solar radiation. DIC and DO...

  13. Geopressured-geothermal test of the EDNA Delcambre No. 1 well, Tigre Lagoon Field, Vermilion Parish, Louisiana: Analysis of water and dissolved natural gas: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hankind, B.E.; Karkalits, O.C.

    1978-09-01

    The presence of large volumes of hot water (250-425 F) containing dissolved natural gas in the Gulf of Mexico coastal areas at depths of 5,000 to 25,000 feet (the geopressured zone) has been known for several years. Because natural gas and oil from conventional production methods were relatively inexpensive prior to 1973, and because foreign oil was readily available, no economic incentive existed for developing this resource. With the oil embargo and the resulting rapid escalation in prices of oil and gas since 1973, a new urgency exists for examining the economic potential of the geopressured-geothermal resource. The main objective of the research reported here was to determine the volume of gas dissolved in the geopressured water, as well as the qualitative and quantitative composition of the water and the dissolved gas. A further objective was to use an existing shut-in gas well so that drilling time and the attendant costs could be avoided.

  14. Time-dependent analysis of dissolver off-gas cleaning installations in a reprocessing plant

    International Nuclear Information System (INIS)

    Nagel, K.; Furrer, J.; Becker, G.; Obrowski, W.; Seghal, Y.P.; Weymann, J.

    1983-01-01

    The iodine- and aerosol-filtering test facility PASSAT of the Nuclear Research Centre in Karlsruhe has been investigated using a method which allows time-dependent analyses under accident conditions. This method which is closely related to fault-tree analysis needs subdivision in barriers of the system, and their logical combination in a tree. The barriers have binary states: defect and intact. The defect state will be described by a fault tree, whereas the intact state includes dependences of a barrier operation on physical parameters. The intact state enables time-dependent calculations. Calculations have been done for iodine filtering, because the best known entrance data are given. Results demonstrate clearly that the amount of iodine released increases only if both heaters failed, which heat the off-gas from 30 0 C to 80 0 C and then to 130 0 C. Additionally the integrated amount of iodine released depends on time period between the failures of the heaters

  15. Update on the use of dissolved oxygen addition to monitor the effectiveness of noble metal applications in external manifolds

    International Nuclear Information System (INIS)

    Varela, J.A.; Huie, H.H.; Seeman, R.A.; Bourne, C.M.; Odell, A.D.

    2014-01-01

    Electrochemical corrosion potential (ECP) measurements in a Mitigation Monitoring System (MMS) ECP manifold have historically been a primary indicator of the effectiveness of an On-Line NobleChem™ (OLNC) application, with the MMS ECP intended to measure the catalytic effect of noble metal deposited on the ECP manifold surface. In some plants ECP measurements made on untreated surfaces prior to an OLNC application were significantly lower than what would be expected for stainless steel under reactor bulk chemistry conditions. This is due to the consumption and depletion of bulk liquid dissolved oxygen (DO) in the lines supplying reactor water to these external ECP measurement locations. This phenomenon degrades the ability to use these external manifolds to confirm noble metal deposition. Previous papers have described how the injection of an oxygen-rich stream to the MMS supply stream (DO Addition) can be used to re-establish the capability of external ECP measurements to monitor the catalytic behavior of platinum deposited during an OLNC injection. This paper will provide an update of how this method is being successfully used in operating BWRs to monitor OLNC injections. The paper will outline the overall approach used to characterize the catalytic behavior of external ECP manifolds before and after the noble metal application and present plant data collected during DO Additions performed under various conditions. (author)

  16. Organic iodine removal from simulated dissolver off-gas systems utilizing silver-exchanged mordenite

    International Nuclear Information System (INIS)

    Jubin, R.T.

    1981-01-01

    The removal of methyl iodide by adsorption onto silver mordenite was studied using a simulated off-gas from the fuel dissolution step of a nuclear fuel reprocessing plant. The adsorption of methyl iodide on silver mordenite was examined for the effect of NO/sub x/, humidity, iodine concentration, filter temperature, silver loadings and filter pretreatment. The highest iodine loading achieved in these tests was 142 mg CH 3 I per g of substrate on fully exchanged zeolite, approximately the same as elemental iodine loadings. A filter using fully exchanged silver mordenite operating at 200 0 C obtained higher iodine loadings than a similar filter operating at 150 0 C. Pretreatment of the sorbent bed with hydrogen rather than dry air, at a temperature of 200 0 C, also improved the loading. Variations in the methyl iodide concentration had minimal effects on the overall loading. Filters exposed to moist air streams attained higher loadings than those in contact with dry air. Partially exchanged silver mordenite achieved higher silver utilizations than the fully exchanged material. The partially exchanged mordenite also achieved higher loadings at 200 0 C than at 250 0 C. The iodine loaded onto these beds was not stripped at 500 0 C by either 4.5% hydrogen or 100% hydrogen; however, the iodine could be removed by air at 500 0 C, and the bed could be reloaded. A study of the regeneration characteristics of fully exchanged silver mordenite indicates limited adsorbent capacity after complete removal of the iodine with 4.5% hydrogen in the regeneration gas stream at 500 0 C. The loss of adsorbent capacity is much higher for silver mordenite regenerated in a stainless steel filter housing than in a glass filter housing

  17. Continuous intra-arterial blood-gas monitoring

    Science.gov (United States)

    Divers, George A.; Riccitelli, Samuel D.; Blais, Maurice; Hui, Henry K.

    1993-05-01

    Fiber optic technology and optical fluorescence have made the continuous monitoring of arterial blood gases a reality. Practical products that continuously monitor blood gases by use of an invasive sensor are now available. Anesthesiologists and intensive care physicians are beginning to explore the practical implications of this technology. With the advent of intra- arterial blood gas monitors it is possible to assess arterial blood gas values without the labor intensive steps of drawing blood and transporting a blood sample to the lab followed by the actual analysis. These intra-arterial blood gas monitors use new optical sensor technologies that can be reduced in size to the point that the sensor can be inserted into the arterial blood flow through a 20-gauge arterial cannula. In the best of these technologies the sensors accuracy and precision are similar to those in vitro analyzers. This presentation focuses on background technology and in vivo performance of a device developed, manufactured, and marketed by Puritan-Bennett Corporation.

  18. New generation enrichment monitoring technology for gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Ianakiev, Kiril D.; Alexandrov, Boian S.; Boyer, Brian D.; Hill, Thomas R.; Macarthur, Duncan W.; Marks, Thomas; Moss, Calvin E.; Sheppard, Gregory A.; Swinhoe, Martyn T.

    2008-01-01

    The continuous enrichment monitor, developed and fielded in the 1990s by the International Atomic Energy Agency, provided a go-no-go capability to distinguish between UF 6 containing low enriched (approximately 4% 235 U) and highly enriched (above 20% 235 U) uranium. This instrument used the 22-keV line from a 109 Cd source as a transmission source to achieve a high sensitivity to the UF 6 gas absorption. The 1.27-yr half-life required that the source be periodically replaced and the instrument recalibrated. The instrument's functionality and accuracy were limited by the fact that measured gas density and gas pressure were treated as confidential facility information. The modern safeguarding of a gas centrifuge enrichment plant producing low-enriched UF 6 product aims toward a more quantitative flow and enrichment monitoring concept that sets new standards for accuracy stability, and confidence. An instrument must be accurate enough to detect the diversion of a significant quantity of material, have virtually zero false alarms, and protect the operator's proprietary process information. We discuss a new concept for advanced gas enrichment assay measurement technology. This design concept eliminates the need for the periodic replacement of a radioactive source as well as the need for maintenance by experts. Some initial experimental results will be presented.

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

    International Nuclear Information System (INIS)

    Sherwood, D.J.

    1995-01-01

    Flammable gases generated in radioactive liquids. Twenty-five high level radioactive liquid waste storage tanks located underground at the Hanford Site are on a Flammable Gas Watch List because they contain waste which tends to retain the gases generated in it until rather large quantities are available for sudden release to the tank head space; if a tank is full it has little dome space, and a flammable concentration of gases could be produced--even if the tank is ventilated. If the waste has no tendency to retain gas generated in it then a continual flammable gas concentration in the tank dome space is established by the gas production rate and the tank ventilation rate (or breathing rate for unventilated tanks); this is also a potential problem for Flammable Gas Watch List tanks, and perhaps other Hanford tanks too. All Flammable Gas Watch List tanks will be fitted with Standard Hydorgen Monitoring Systems so that their behavior can be observed. In some cases, such as tank 241-SY-101, the data gathered from such observations will indicate that tank conditions need to be mitigated so that gas release events are either eliminated or rendered harmless. For example, a mixer pump was installed in tank 241-SY-101; operating the pump stirs the waste, replacing the large gas release events with small releases of gas that are kept below twenty-five percent of the lower flammability limit by the ventilation system. The concentration of hydrogen measured in Hanford waste tanks is greater than that of any other flammable gas. Hydrogen levels measured with a Standard Hydrogen Monitoring System in excess of 0.6 volume percent will cause Westinghouse Hanford Company to consider actions which will decrease the amount of flammable gas in the tank

  20. 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

  1. A SIGNAL ENHANCED PORTABLE RAMAN PROBE FOR ANESTHETIC GAS MONITORING

    Directory of Open Access Journals (Sweden)

    S. Schlüter

    2015-03-01

    Full Text Available The spontaneous Raman scattering technique is an excellent tool for a quantitative analysis of multi-species gas mixtures. It is a noninvasive optical method for species identification and gas phase concentration measurement of all Raman active molecules, since the intensity of the species specific Raman signal is linearly dependent on the concentration. Applying a continuous wave (CW laser it typically takes a few seconds to capture a gas phase Raman spectrum at room temperature. Nevertheless in contrast to these advantages the weak Raman signal intensity is a major drawback. Thus, it is still challenging to detect gas phase Raman spectra in alow-pressure regime with a temporal resolution of only a few 100 ms. In this work a fully functional gas phase Raman system for measurements in the low-pressure regime (p ≥ 980 hPa (absolute is presented. It overcomes the drawback of a weak Raman signal by using a multipass cavity. A description of the sensor setup and of the multipass arrangement will be presented. Moreover the complete functionality of the sensor system will be demonstrated by measurements at an anesthesia simulator under clinical relevant conditions and in comparison to a conventional gas monitor.

  2. Using dissolved gas analysis to investigate the performance of an organic carbon permeable reactive barrier for the treatment of mine drainage

    Science.gov (United States)

    Williams, R.L.; Mayer, K.U.; Amos, R.T.; Blowes, D.W.; Ptacek, C.J.; Bain, J.G.

    2007-01-01

    The strongly reducing nature of permeable reactive barrier (PRB) treatment materials can lead to gas production, potentially resulting in the formation of gas bubbles and ebullition. Degassing in organic C based PRB systems due to the production of gases (primarily CO2 and CH4) is investigated using the depletion of naturally occurring non-reactive gases Ar and N2, to identify, confirm, and quantify chemical and physical processes. Sampling and analysis of dissolved gases were performed at the Nickel Rim Mine Organic Carbon PRB, which was designed for the treatment of groundwater contaminated by low quality mine drainage characterized by slightly acidic pH, and elevated Fe(II) and SO4 concentrations. A simple 4-gas degassing model was used to analyze the dissolved gas data, and the results indicate that SO4 reduction is by far the dominant process of organic C consumption within the barrier. The data provided additional information to delineate rates of microbially mediated SO4 reduction and confirm the presence of slow and fast flow zones within the barrier. Degassing was incorporated into multicomponent reactive transport simulations for the barrier and the simulations were successful in reproducing observed dissolved gas trends.

  3. Environmental monitoring in the gas industry of Russia

    International Nuclear Information System (INIS)

    Sedykh, A.D.; Dinkov, V.A.; Gritsenko, A.I.; Bosnyatsky, G.P.; Maksimov, V.M.

    1997-01-01

    The paper describes the basic principles and targets of production pollution monitoring (PPM) along with the analysis of structure, content and main functions of PPM relative to the experience of EEC and existing legislative and normative basis. The comparison, quantitative and qualitative analysis of pollutant emission at the Russian gas industry enterprises is given. Promising scientific and research targets the solution of which will promote improvement of ecological situation and will allow to meet international environmental agreements have been formulated. (au)

  4. Noble gas geochemistry to monitor CO2 geological storages

    International Nuclear Information System (INIS)

    Lafortune, St.

    2007-11-01

    According to the last IPCC (Intergovernmental Panel on Climate Change) report, a probability of 90 % can be now established for the responsibility of the anthropogenic CO 2 emissions for the global climate change observed since the beginning of the 20. century. To reduce these emissions and keep producing energy from coal, oil or gas combustions, CO 2 could be stored in geological reservoirs like aquifers, coal beds, and depleted oil or gas fields. Storing CO 2 in geological formations implies to control the efficiency and to survey the integrity of the storages, in order to be able to detect the possible leaks as fast as possible. Here, we study the feasibility of a geochemical monitoring through noble gas geochemistry. We present (1) the development of a new analytical line, Garodiox, developed to extract quantitatively noble gas from water samples, (2) the testing of Garodiox on samples from a natural CO 2 storage analogue (Pavin lake, France) and (3) the results of a first field work on a natural CO 2 accumulation (Montmiral, France). The results we obtain and the conclusions we draw, highlight the interest of the geochemical monitoring we suggest. (author)

  5. A stream-based methane monitoring approach for evaluating groundwater impacts associated with unconventional gas development.

    Science.gov (United States)

    Heilweil, Victor M; Stolp, Bert J; Kimball, Briant A; Susong, David D; Marston, Thomas M; Gardner, Philip M

    2013-01-01

    Gaining streams can provide an integrated signal of relatively large groundwater capture areas. In contrast to the point-specific nature of monitoring wells, gaining streams coalesce multiple flow paths. Impacts on groundwater quality from unconventional gas development may be evaluated at the watershed scale by the sampling of dissolved methane (CH4 ) along such streams. This paper describes a method for using stream CH4 concentrations, along with measurements of groundwater inflow and gas transfer velocity interpreted by 1-D stream transport modeling, to determine groundwater methane fluxes. While dissolved ionic tracers remain in the stream for long distances, the persistence of methane is not well documented. To test this method and evaluate CH4 persistence in a stream, a combined bromide (Br) and CH4 tracer injection was conducted on Nine-Mile Creek, a gaining stream in a gas development area in central Utah. A 35% gain in streamflow was determined from dilution of the Br tracer. The injected CH4 resulted in a fivefold increase in stream CH4 immediately below the injection site. CH4 and δ(13) CCH4 sampling showed it was not immediately lost to the atmosphere, but remained in the stream for more than 2000 m. A 1-D stream transport model simulating the decline in CH4 yielded an apparent gas transfer velocity of 4.5 m/d, describing the rate of loss to the atmosphere (possibly including some microbial consumption). The transport model was then calibrated to background stream CH4 in Nine-Mile Creek (prior to CH4 injection) in order to evaluate groundwater CH4 contributions. The total estimated CH4 load discharging to the stream along the study reach was 190 g/d, although using geochemical fingerprinting to determine its source was beyond the scope of the current study. This demonstrates the utility of stream-gas sampling as a reconnaissance tool for evaluating both natural and anthropogenic CH4 leakage from gas reservoirs into groundwater and surface water

  6. Microfabricated BTU monitoring device for system-wide natural gas monitoring.

    Energy Technology Data Exchange (ETDEWEB)

    Einfeld, Wayne; Manginell, Ronald Paul; Robinson, Alex Lockwood; Moorman, Matthew Wallace

    2005-11-01

    The natural gas industry seeks inexpensive sensors and instrumentation to rapidly measure gas heating value in widely distributed locations. For gas pipelines, this will improve gas quality during transfer and blending, and will expedite accurate financial accounting. Industrial endusers will benefit through continuous feedback of physical gas properties to improve combustion efficiency during use. To meet this need, Sandia has developed a natural gas heating value monitoring instrument using existing and modified microfabricated components. The instrument consists of a silicon micro-fabricated gas chromatography column in conjunction with a catalytic micro-calorimeter sensor. A reference thermal conductivity sensor provides diagnostics and surety. This combination allows for continuous calorimetric determination with a 1 minute analysis time and 1.5 minute cycle time using air as a carrier gas. This system will find application at remote natural gas mining stations, pipeline switching and metering stations, turbine generators, and other industrial user sites. Microfabrication techniques will allow the analytical components to be manufactured in production quantities at a low per-unit cost.

  7. Technical Note: Precise quantitative measurements of total dissolved inorganic carbon from small amounts of seawater using a gas chromatographic system

    Directory of Open Access Journals (Sweden)

    T. Hansen

    2013-10-01

    Full Text Available Total dissolved inorganic carbon (CT is one of the most frequently measured parameters used to calculate the partial pressure of carbon dioxide in seawater. Its determination has become increasingly important because of the rising interest in the biological effects of ocean acidification. Coulometric and infrared detection methods are currently favored in order to precisely quantify CT. These methods however are not sufficiently validated for CT measurements of biological experiments manipulating seawater carbonate chemistry with an extended CT measurement range (~1250–2400 μmol kg–1 compared to natural open ocean seawater (~1950–2200 μmol kg−1. The requirement of total sample amounts between 0.1–1 L seawater in the coulometric- and infrared detection methods potentially exclude their use for experiments working with much smaller volumes. Additionally, precise CT analytics become difficult with high amounts of biomass (e.g., phytoplankton cultures or even impossible in the presence of planktonic calcifiers without sample pre-filtration. Filtration however, can alter CT concentration through gas exchange induced by high pressure. Addressing these problems, we present precise quantification of CT using a small, basic and inexpensive gas chromatograph as a CT analyzer. Our technique is able to provide a repeatability of ±3.1 μmol kg−1, given by the pooled standard deviation over a CT range typically applied in acidification experiments. 200 μL of sample is required to perform the actual CT measurement. The total sample amount needed is 12 mL. Moreover, we show that sample filtration is applicable with only minor alteration of the CT. The method is simple, reliable and with low cumulative material costs. Hence, it is potentially attractive for all researchers experimentally manipulating the seawater carbonate system.

  8. Identification of transformer fault based on dissolved gas analysis using hybrid support vector machine-modified evolutionary particle swarm optimisation

    Science.gov (United States)

    2018-01-01

    Early detection of power transformer fault is important because it can reduce the maintenance cost of the transformer and it can ensure continuous electricity supply in power systems. Dissolved Gas Analysis (DGA) technique is commonly used to identify oil-filled power transformer fault type but utilisation of artificial intelligence method with optimisation methods has shown convincing results. In this work, a hybrid support vector machine (SVM) with modified evolutionary particle swarm optimisation (EPSO) algorithm was proposed to determine the transformer fault type. The superiority of the modified PSO technique with SVM was evaluated by comparing the results with the actual fault diagnosis, unoptimised SVM and previous reported works. Data reduction was also applied using stepwise regression prior to the training process of SVM to reduce the training time. It was found that the proposed hybrid SVM-Modified EPSO (MEPSO)-Time Varying Acceleration Coefficient (TVAC) technique results in the highest correct identification percentage of faults in a power transformer compared to other PSO algorithms. Thus, the proposed technique can be one of the potential solutions to identify the transformer fault type based on DGA data on site. PMID:29370230

  9. Identification of transformer fault based on dissolved gas analysis using hybrid support vector machine-modified evolutionary particle swarm optimisation.

    Directory of Open Access Journals (Sweden)

    Hazlee Azil Illias

    Full Text Available Early detection of power transformer fault is important because it can reduce the maintenance cost of the transformer and it can ensure continuous electricity supply in power systems. Dissolved Gas Analysis (DGA technique is commonly used to identify oil-filled power transformer fault type but utilisation of artificial intelligence method with optimisation methods has shown convincing results. In this work, a hybrid support vector machine (SVM with modified evolutionary particle swarm optimisation (EPSO algorithm was proposed to determine the transformer fault type. The superiority of the modified PSO technique with SVM was evaluated by comparing the results with the actual fault diagnosis, unoptimised SVM and previous reported works. Data reduction was also applied using stepwise regression prior to the training process of SVM to reduce the training time. It was found that the proposed hybrid SVM-Modified EPSO (MEPSO-Time Varying Acceleration Coefficient (TVAC technique results in the highest correct identification percentage of faults in a power transformer compared to other PSO algorithms. Thus, the proposed technique can be one of the potential solutions to identify the transformer fault type based on DGA data on site.

  10. Identification of transformer fault based on dissolved gas analysis using hybrid support vector machine-modified evolutionary particle swarm optimisation.

    Science.gov (United States)

    Illias, Hazlee Azil; Zhao Liang, Wee

    2018-01-01

    Early detection of power transformer fault is important because it can reduce the maintenance cost of the transformer and it can ensure continuous electricity supply in power systems. Dissolved Gas Analysis (DGA) technique is commonly used to identify oil-filled power transformer fault type but utilisation of artificial intelligence method with optimisation methods has shown convincing results. In this work, a hybrid support vector machine (SVM) with modified evolutionary particle swarm optimisation (EPSO) algorithm was proposed to determine the transformer fault type. The superiority of the modified PSO technique with SVM was evaluated by comparing the results with the actual fault diagnosis, unoptimised SVM and previous reported works. Data reduction was also applied using stepwise regression prior to the training process of SVM to reduce the training time. It was found that the proposed hybrid SVM-Modified EPSO (MEPSO)-Time Varying Acceleration Coefficient (TVAC) technique results in the highest correct identification percentage of faults in a power transformer compared to other PSO algorithms. Thus, the proposed technique can be one of the potential solutions to identify the transformer fault type based on DGA data on site.

  11. Bedside arterial blood gas monitoring system using fluorescent optical sensors

    Science.gov (United States)

    Bartnik, Daniel J.; Rymut, Russell A.

    1995-05-01

    We describe a bedside arterial blood gas (ABG) monitoring system which uses fluorescent optical sensors in the measurement of blood pH, PCO2 and PO2. The Point-of-Care Arterial Blood Gas Monitoring System consists of the SensiCathTM optical sensor unit manufactured by Optical Sensors Incorporated and the TramTM Critical Care Monitoring System with ABG Module manufactured by Marquette Electronics Incorporated. Current blood gas measurement techniques require a blood sample to be removed from the patient and transported to an electrochemical analyzer for analysis. The ABG system does not require removal of blood from the patient or transport of the sample. The sensor is added to the patient's existing arterial line. ABG measurements are made by drawing a small blood sample from the arterial line in sufficient quantity to ensure an undiluted sample at the sensor. Measurements of pH, PCO2 and PO2 are made within 60 seconds. The blood is then returned to the patient, the line flushed and results appear on the bedside monitor. The ABG system offers several advantages over traditional electrochemical analyzers. Since the arterial line remains closed during the blood sampling procedure the patient's risk of infection is reduced and the caregiver's exposure to blood is eliminated. The single-use, disposable sensor can be measure 100 blood samples over 72 hours after a single two-point calibration. Quality Assurance checks are also available and provide the caregiver the ability to assess system performance even after the sensor is patient attached. The ABG module integrates with an existing bedside monitoring system. This allows ABG results to appear on the same display as ECG, respiration, blood pressure, cardiac output, SpO2, and other clinical information. The small module takes up little space in the crowded intensive care unit. Performance studies compare the ABG system with an electrochemical blood gas analyzer. Study results demonstrated accurate and precise blood

  12. Long-term monitoring of marine gas leakage

    Science.gov (United States)

    Spickenbom, Kai; Faber, Eckhard; Poggenburg, Jürgen; Seeger, Christian; Furche, Markus

    2010-05-01

    The sequestration of CO2 in sub-seabed geological formations is one of the Carbon Capture and Storage (CCS) strategies currently under study. Although offshore operations are significantly more expensive than comparable onshore operations, the growing public resistance against onshore CCS projects makes sub-seabed storage a promising option. Even after a thorough review of the geological setting, there is always the possibility of leakage from the reservoir. As part of the EU-financed project CO2ReMoVe (Research, Monitoring, Verification), which aims to develop innovative research and technologies for monitoring and verification of carbon dioxide geological storage, we are working on the development of submarine long-term gas flow monitoring systems. The basic design of the monitoring system builds on our experience in volcano monitoring. Early prototypes were composed of a raft floating on the surface of a mud volcano, carrying sensors for CO2 flux and concentration, data storage and transmission, and power supply by battery-buffered solar panels. The system was modified for installation in open sea by using a buoy instead of a raft and a funnel on the seafloor to collect the gas, connected by a flexible tube. This setup provides a cost-effective solution for shallow waters. However, a buoy interferes with ship traffic, and it is also difficult to adapt this design to greater water depths. These requirements can best be complied by a completely submersed system. A system for unattended long-term monitoring in a marine environment has to be extremely durable. Therefore, we focussed on developing a mechanically and electrically as simple setup as possible, which has the additional advantage of low cost. The system consists of a funnel-shaped gas collector, a sensor head and pressure housings for electronics and power supply. Since this setup is inexpensive, it can be deployed in numbers to cover larger areas. By addition of multi-channel data loggers, data

  13. Laser Gas-Analyser for Monitoring a Source of Gas Pollution

    Directory of Open Access Journals (Sweden)

    V. A. Gorodnichev

    2015-01-01

    Full Text Available Currently, the problem of growing air pollution of the Earth is of relevance. Many countries have taken measures to protect the environment in order to limit the negative anthropogenic impacts.In such a situation an objective information on the actual content of pollutants in the atmosphere is of importance. For operational inspection of the pollutant concentrations and for monitoring pollution sources, it is necessary to create high-speed high-sensitivity gas analysers.Laser meters are the most effective to provide operational remote and local inspection of gas pollution of the Earth atmosphere.Laser meter for routine gas analysis should conduct operational analysis of the gas mixture (air. For this a development of appropriate information support is required.Such information support should include a database with absorption coefficients of pollutants (specific to potential sources of pollution at possible measuring wavelengths (holding data for a particular emitter of the laser meter and an efficient algorithms to search the measuring wavelengths and conduct a quantitative analysis of gas mixtures.Currently, the issues, important for practice and related to the development of information support for the laser gas analyzer to conduct important for practice routine measurements remain unclear.In this paper we develop an algorithm to provide an operational search of the measuring wavelengths of laser gas analyser and an algorithm to recover quantitively the gaseous component concentrations of controlled gas mixture from the laser multi-spectral measurements that take into account a priori information about the source-controlled gas pollution and do not require a large amount of computation. The method of mathematical simulation shows the effectiveness of the algorithms described both for seach of measuring wavelengths and for quantitative analysis of gas releases.

  14. Monitor large-scale consumers market natural gas and electricity 2010; Monitor groothandelsmarkten gas en elektriciteit 2010

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-02-15

    The Office of Energy Regulation ('Energiekamer') carries out its legal task by means of a monitor, a practical tool to assess and analyze the wholesale market for electricity. Monitoring of the wholesale electricity market concerns continuous, accurate and structured following of developments in the market. The aim is to identify in time signals from the market that could lead to a decrease of competition and transparency. The starting point of the monitor for the wholesale electricity market is the selection of indicators which give insight in real competition, liquidity and transparency. [Dutch] De Energiekamer schrijft jaarlijks haar bevindingen over de mate van marktwerking in de groothandelsmarkten gas en elektriciteit in een rapport aan de Minister van Economische Zaken. Dit rapport is de monitor. Sinds 2007 zijn de bevindingen over de groothandelsmarkten voor gas en elektriciteit samengevoegd in een publicatie. Concreet verzamelt de Energiekamer marktinformatie zoals prijzen en hoeveelheden. Daarnaast bestudeert de Energiekamer of deze uitkomsten overeenkomen met wat beoogd was in de vrije energiemarkt. De Energiekamer onderzoekt of de voorwaarden (zoals bijvoorbeeld toetredingsbarrieres en transparantie) optimaal zijn voor doeltreffende concurrentie en geeft voorstellen van maatregelen om de marktwerking te verbeteren.

  15. Monitoring terrestrial dissolved organic carbon export at land-water interfaces using remote sensing

    Science.gov (United States)

    Yu, Q.; Li, J.; Tian, Y. Q.

    2017-12-01

    Carbon flux from land to oceans and lakes is a crucial component of carbon cycling. However, this lateral carbon flow at land-water interface is often neglected in the terrestrial carbon cycle budget, mainly because observations of the carbon dynamics are very limited. Monitoring CDOM/DOC dynamics using remote sensing and assessing DOC export from land to water remains a challenge. Current CDOM retrieval algorithms in the field of ocean color are not simply applicable to inland aquatic ecosystems since they were developed for coarse resolution ocean-viewing imagery and less complex water types in open-sea. We developed a new semi-analytical algorithm, called SBOP (Shallow water Bio-Optical Properties algorithm) to adapt to shallow inland waters. SBOP was first developed and calibrated based on in situ hyperspectral radiometer data. Then we applied it to the Landsat-8 OLI images and evaluated the effectiveness of the multispectral images on inversion of CDOM absorption based on our field sampling at the Saginaw Bay in the Lake Huron. The algorithm performances (RMSE = 0.17 and R2 = 0.87 in the Saginaw Bay; R2 = 0.80 in the northeastern US lakes) is promising and we conclude the CDOM absorption can be derived from Landsat-8 OLI image in both optically deep and optically shallow waters with high accuracy. Our method addressed challenges on employing appropriate atmospheric correction, determining bottom reflectance influence for shallow waters, and improving for bio-optical properties retrieval, as well as adapting to both hyperspectral and the multispectral remote sensing imagery. Over 100 Landsat-8 images in Lake Huron, northeastern US lakes, and the Arctic major rivers were processed to understand the CDOM spatio-temporal dynamics and its associated driving factors.

  16. Gas bubble trauma monitoring and research of juvenile salmonids. 1995 Annual report

    International Nuclear Information System (INIS)

    Maule, A.G.; Mesa, M.G.; Hans, K.M.

    1997-07-01

    This report describes laboratory and field monitoring studies of gas bubble trauma (GBT) in migrating juvenile salmonids in the Snake and Columbia rivers. The first chapter describes laboratory studies of the progression of GBT signs leading to mortality and the use of the signs for GBT assessment. The progression and severity of GBT signs in juvenile salmonids exposed to different levels of total dissolved gas (TDG) and temperatures was assessed and quantified. Next, the prevalence, severity, and individual variation of GBT signs was evaluated to attempt to relate them to mortality. Finally, methods for gill examination in fish exposed to high TDG were developed and evaluated. Primary findings were: (1) no single sign of GBT was clearly correlated with mortality, but many GBT signs progressively worsened; (2) both prevalence and severity of GBT signs in several tissues is necessary; (3) bubbles in the lateral line were the earliest sign of GBT, showed progressive worsening, and had low individual variation but may develop poorly during chronic exposures; (4) fin bubbles had high prevalence, progressively worsened, and may be a persistent sign of GBT; and (5) gill bubbles appear to be the proximate cause of death but may only be relevant at high TDG levels and are difficult to examine. Chapter Two describes monitoring results of juvenile salmonids for signs of GBT. Emigrating fish were collected and examined for bubbles in fins and lateral lines. Preliminary findings were: (1) few fish had signs of GBT, but prevalence and severity appeared to increase as fish migrated downstream; (2) there was no apparent correlation between GBT signs in the fins, lateral line, or gills; (3) prevalence and severity of GBT was suggestive of long-term, non-lethal exposure to relatively low level gas supersaturated water; and (4) it appeared that GBT was not a threat to migrating juvenile salmonids. 24 refs., 26 figs., 3 tabs

  17. Iodine and NOx behavior in the dissolver off-gas and IODOX [Iodine Oxidation] systems in the Oak Ridge National Laboratory Integrated Equipment Test facility

    International Nuclear Information System (INIS)

    Birdwell, J.F.

    1990-01-01

    This paper describes the most recent in a series of experiments evaluating the behavior of iodine and NO x in the Integrated Equipment Test (IET) Dissolver Off-Gas (DOG) System. This work was performed as part of a joint collaborative program between the US Department of Energy and the Power and Nuclear Fuel Development Corporation of Japan. The DOG system consists of two shell-and-tube heat exchangers in which water and nitric acid are removed from the dissolver off-gas by condensation, followed by a packed tower in which NO x is removed by absorption into a dilute nitric acid solution. The paper also describes the results of the operation of the Iodine Oxidation (IODOX) System. This system serves to remove iodine from the DOG system effluent by absorption into hyperazeotropic nitric acid. 7 refs., 11 figs., 10 tabs

  18. Reactor cover gas monitoring at the Fast Flux Test Facility

    International Nuclear Information System (INIS)

    Bechtold, R.A.; Holt, F.E.; Meadows, G.E.; Schenter, R.E.

    1986-09-01

    The Fast Flux Test Facility (FFTF) is a 400-megawatt (thermal) sodium-cooled reactor designed for irradiation testing of fuels, materials and components for LMRs. It is operated by the Westinghouse Hanford Company for the US Department of Energy on the government-owned Hanford reservation near Richland, Washington. The first 100-day operating cycle began in April 1982 and the eighth operating cycle was completed in July 1986. Argon is used as the cover gas for all sodium systems at the plant. A program for cover gas monitoring has been in effect since the start of sodium fill in 1978. The argon is supplied to the FFTF by a liquid argon Dewar System and used without further purification

  19. California GAMA Special Study: An isotopic and dissolved gas investigation of nitrate source and transport to a public supply well in California's Central Valley

    Energy Technology Data Exchange (ETDEWEB)

    Singleton, M J; Moran, J E; Esser, B K; Roberts, S K; Hillegonds, D J

    2010-04-14

    This study investigates nitrate contamination of a deep municipal drinking water production well in Ripon, CA to demonstrate the utility of natural groundwater tracers in constraining the sources and transport of nitrate to deep aquifers in the Central Valley. The goal of the study was to investigate the origin (source) of elevated nitrate and the potential for the deep aquifer to attenuate anthropogenic nitrate. The site is ideal for such an investigation. The production well is screened from 165-325 feet below ground surface and a number of nearby shallow and deep monitoring wells were available for sampling. Furthermore, potential sources of nitrate contamination to the well had been identified, including a fertilizer supply plant located approximately 1000 feet to the east and local almond groves. A variety of natural isotopic and dissolved gas tracers including {sup 3}H-{sup 3}He groundwater age and the isotopic composition of nitrate are applied to identify nitrate sources and to characterize nitrate transport. An advanced method for sampling production wells is employed to help identify contaminant contributions from specific screen intervals. Nitrate transport: Groundwater nitrate at this field site is not being actively denitrified. Groundwater parameters indicate oxic conditions, the dissolved gas data shows no evidence for excess nitrogen as the result of denitrification, and nitrate-N and -O isotope compositions do not display patterns typical of denitrification. Contaminant nitrate source: The ambient nitrate concentration in shallow groundwater at the Ripon site ({approx}12 mg/L as nitrate) is typical of shallow groundwaters affected by recharge from agricultural and urban areas. Nitrate concentrations in Ripon City Well 12 (50-58 mg/L as nitrate) are significantly higher than these ambient concentrations, indicating an additional source of anthropogenic nitrate is affecting groundwater in the capture zone of this municipal drinking water well. This

  20. Fission product range effects on HEU fissile gas monitoring for UF6 gas

    International Nuclear Information System (INIS)

    Munro, J.K. Jr.; Valentine, T.E.; Perez, R.B.

    1997-01-01

    The amount of 235 U in UF 6 flowing in a pipe can be monitored by counting gamma rays emitted from fission fragments carried along by the flowing gas. Neutron sources are mounted in an annular sleeve that is filled with moderator material and surrounds the pipe. This provides a source of thermal neutrons to produce the fission fragments. Those fragments that remain in the gas stream following fission are carried past a gamma detector. A typical fragment will be quite unstable, giving up energy as it decays to a more stable isotope with a significant amount of this energy being emitted in the form of gamma rays. A given fragment can emit several gamma rays over its lifetime. The gamma ray emission activity level of a distribution of fission fragments decreases with time. The monitoring system software uses models of these processes to interpret the gamma radiation counting data measured by the gamma detectors

  1. Fish Individual-based Numerical Simulator (FINS): A particle-based model of juvenile salmonid movement and dissolved gas exposure history in the Columbia River Basin

    International Nuclear Information System (INIS)

    Scheibe, Timothy D.; Richmond, Marshall C.

    2002-01-01

    This paper describes a numerical model of juvenile salmonid migration in the Columbia and Snake Rivers. The model, called the Fish Individual-based Numerical Simulator or FINS, employs a discrete, particle-based approach to simulate the migration and history of exposure to dissolved gases of individual fish. FINS is linked to a two-dimensional (vertically-averaged) hydrodynamic simulator that quantifies local water velocity, temperature, and dissolved gas levels as a function of river flow rates and dam operations. Simulated gas exposure histories can be input to biological mortality models to predict the effects of various river configurations on fish injury and mortality due to dissolved gas supersaturation. Therefore, FINS serves as a critical linkage between hydrodynamic models of the river system and models of biological impacts. FINS was parameterized and validated based on observations of individual fish movements collected using radiotelemetry methods during 1997 and 1998 . A quasi-inverse approach was used to decouple fish swimming movements from advection with the local water velocity, allowing inference of time series of non-advective displacements of individual fish from the radiotelemetry data. Statistical analyses of these displacements are presented, and confirm that strong temporal correlation of fish swimming behavior persists in some cases over several hours. A correlated random-walk model was employed to simulate the observed migration behavior, and parameters of the model were estimated that lead to close correspondence between predictions and observations

  2. Development of monitoring and control technology based on trace gas monitoring. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Liebowitz, B.

    1997-07-01

    Trace gases are generated by many biological reactions. During anaerobic decomposition, trace levels of hydrogen (H{sub 2}) and carbon monoxide (CO) gases are produced. It was shown previously that these trace gases are intrinsically related to the biochemical reactions occurring and, therefore, offer promise for on-line process monitoring and control. This work was designed to test how effectively hydrogen and CO could be to monitor high-rate anaerobic systems that has significant mass transfer and complex hydraulics. An experimental program was designed to examine the behavior of an upflow anaerobic sludge blanket (UASB) reactor system under steady state and in response to organic loading perturbations. The responses of trace gases CO and H{sub 2} were tracked using an on-line, real-time gas-monitoring system linked to a computer-controlled data acquisition package. Data on conventional process parameters such as pH, chemical oxygen demand (COD), volatile fatty acids (VFAs) were concurrently collected. Monitoring of conventional process indicators (i.e., pH, VFA, gas production) and trace gas (H{sub 2} and CO) indicators was conducted using a matrix of nine different steady-state OLRs (4-23 kg COD/m{sup 3} -d) and system HRTs (0.5 to 2.5 days) was performed to determine any correlation among the indicators. Of OLR, HRT, and influent COD, only OLR had any significant influence on the process indicators examined. All parameters except methane increased with increases in OLR; methane decreased with increased OLR. The OLR and gas production rate (GP) were observed to be linearly correlated.

  3. Development of a method for rapid and simultaneous monitoring of particulate and dissolved radiocesium in water with nonwoven fabric cartridge filters

    International Nuclear Information System (INIS)

    Hideki Tsuji; Tetsuo Yasutaka; Yoshihiko Kondo; Yasukazu Suzuki

    2014-01-01

    A method for the rapid and simultaneous monitoring of particulate and dissolved 137 Cs concentration in water was developed. This method uses pleated polypropylene nonwoven fabric filter to collect particulate radiocesium, and nonwoven fabric impregnated with Prussian blue (PB) to absorb dissolved radiocesium. The fabric was placed into cylindrical plastic cartridges (SS-cartridge and PB-cartridge). Traditional monitoring methods, such as evaporative concentration, often require time for pre-processing. However, this method described requires much less pre-processing time before the detection. Experiments conducted with simulated river water demonstrated that almost all of the suspended solids weight was collected in the SS-cartridge, and that more than 92 % of dissolved 137 Cs was absorbed onto the two PB-cartridges by 2.5 L/min flow rate when the range of the pH was 6-8. This device was applied to monitor Abukuma River water at two locations and the results were compared with those obtained using the filtrating and evaporative concentration method. The suspended solids concentration in river water, calculated by weight gain of the SS-cartridge and by sediment weight after filtration with a 0.45-μm membrane filter, agreed well. The radioactivity of the particulate and dissolved 137 Cs also agreed well in one of the two replications of this method. In addition, the required time for pre-processing was reduced by 60 times that by filtrating and evaporative concentration method. This method can separately collect and concentrate particulate and dissolved radiocesium rapidly and simultaneously in the field. (author)

  4. The International Monitoring System's Noble Gas Network

    International Nuclear Information System (INIS)

    Auer, M.

    2015-01-01

    The International Monitoring System (IMS) is a unique global network for surveillance of the Comprehensive Nuclear-Test-Ban Treaty. A major component of the IMS is the radionuclide monitoring network since, among all IMS technologies, it can provide the most unequivocal evidence for a nuclear explosion. The radionuclide monitoring component is unprecedented in its combination of global coverage, sensitivity, network density and temporal resolution. In particular for the detection of underground or underwater nuclear tests, forty of the eighty radionuclide stations will eventually be equipped with sensors to measure the Xenon isotopes Xe-131m (τ 1/2 = 11:8 d), Xe-133 (τ 1/2 = 5:25 d), Xe-133m (τ 1/2 = 2:2 d) and Xe-135 (τ 1/2 = 9:14 h). These are among the isotopes with the highest yields in fission of uranium or plutonium with half-lives long enough to be detected at large distances from the point of emission. As of today, 31 noble gas systems have been installed and are sending data to the International Data Centre. The noble gas systems installed at the stations are automated and sample Xenon continuously from atmospheric air for 12 or 24 hours at an air flow of 0.5 to several m 3 /h by absorption of Xenon on activated charcoal. Detection of the Xenon isotopes is either by high resolution gamma spectrometry or by beta-gamma coincidence spectrometry. With the currently available equipment, detection limits of 0.2 mBq/m 3 can be achieved. An overview on the existing technology and future developments as well as on the interpretation of measurement results is given. (author)

  5. One year monitoring of fire-induced effects on dissolved organic matter and nutrient dynamics under different land-use

    Science.gov (United States)

    Potthast, Karin; Meyer, Stefanie; Crecelius, Anna; Schubert, Ulrich; Michalzik, Beate

    2016-04-01

    It is supposed that the changing climate will promote extreme weather events that in turn will increase drought periods and the abundance of fire events in temperate climate regions such as Central Europe. The impact of fires on the nutrient budgets of ecosystems is highly diverse and seems to depend on the ecosystem type. For example, little is known about fire effects on water-bound organic matter (OM) and nutrient fluxes in temperate managed forest ecosystems. Fires can strongly alter the distribution (forest floor vs. mineral soil), binding forms (organic vs. inorganic) and availability (solubility by water) of OM and associated nutrients. To elucidate the effects and seasonality of low intensity fires on the mobilization of dissolved organic carbon and nutrients, an experimental ground fire was conducted in November 2014 in the Hainich region, Central Germany. In addition, differences in response patterns between two land-use types (pasture and beech forest) were investigated. Lysimeters (n=5 controls/ 5 fire-manipulated) with topsoil monoliths (0-4 cm), rainfall/throughfall samplers, littertraps as well as temperature and moisture sensors were installed on three sites of each land-use type. During the one year of monitoring (Sep14-Dec15) soil solution, rainfall, and throughfall samples were taken biweekly and analyzed for pH, dissolved and particulate organic carbon (DOC, POC) and nitrogen (DN, PN) as well as for nutrients (e.g. K, Ca, Mg, P, S). Compared to the control sites, the ground fire immediately induced a short-run release peak of DOC in both land-use types. Within two weeks these differences were muted in the post-fire period. The effect of fire was land-use specific with annual DOC fluxes of 82 and 45 kg/(ha*a) for forest and pasture sites, respectively. In contrast, nitrogen fluxes responded differently to the fire event. In the forest, a significant increase in DN concentrations was notable five months after the fire, at the beginning of the

  6. Dissolved gases

    International Nuclear Information System (INIS)

    Heaton, T.H.E.

    1981-01-01

    The concentrations of gaseous nitrogen, argon, oxygen and helium dissolved in groundwater are often different from their concentrations in rain and surface waters. These differences reflect changes in the gas content occurring after rain or surface water, having infiltrated into the ground, become isolated from equilibrium contact with the atmosphere. A study of these changes can give insight into the origin and subsequent subsurface history of groundwater. Nitrogen and argon concentrations for many groundwaters in southern Africa indicate that excess air is added to water during infiltration. The amount of excess air is believed to reflect the physical structure of the unsaturated zone and the climate of the recharge area. Since nitrogen and argon are essentially conservative in many aquifer environments in South Africa, their concentrations can be used in distinguishing grondwaters of different recharge origins. In some areas the high helium content of the groundwater suggests that much of the helium is derived through migration from a source outside (e.g. below) the aquifer itself. Radiogenic helium concentrations nevertheless show, in two artesian aquifers, a close linear relationship to the radiocarbon age of the groundwater. This indicates a uniformity in the factors responsible for the accumulation of helium, and suggests that in these circumstances helium data can be used to give information on the age of very old groundwater. In some groundwater dissolved oxygen concentrations are found to decrease with increasing groundwater age. Whilst the rate of decrease may be very different for different aquifers, the field measurement of oxygen may be useful in preliminary surveys directed toward the location of recharge areas

  7. Upgrade to the Cryogenic Hydrogen Gas Target Monitoring System

    Science.gov (United States)

    Slater, Michael; Tribble, Robert

    2013-10-01

    The cryogenic hydrogen gas target at Texas A&M is a vital component for creating a secondary radioactive beam that is then used in experiments in the Momentum Achromat Recoil Spectrometer (MARS). A stable beam from the K500 superconducting cyclotron enters the gas cell and some incident particles are transmuted by a nuclear reaction into a radioactive beam, which are separated from the primary beam and used in MARS experiments. The pressure in the target chamber is monitored so that a predictable isotope production rate can be assured. A ``black box'' received the analog pressure data and sent RS232 serial data through an outdated serial connection to an outdated Visual Basic 6 (VB6) program, which plotted the chamber pressure continuously. The black box has been upgraded to an Arduino UNO microcontroller [Atmel Inc.], which can receive the pressure data and output via USB to a computer. It has been programmed to also accept temperature data for future upgrade. A new computer program, with updated capabilities, has been written in Python. The software can send email alerts, create audible alarms through the Arduino, and plot pressure and temperature. The program has been designed to better fit the needs of the users. Funded by DOE and NSF-REU Program.

  8. Development of Residual Gas Profile Monitors at GSI

    International Nuclear Information System (INIS)

    Giacomini, T.; Forck, P.; Barabin, S.; Liakin, D.; Skachkov, V.

    2004-01-01

    Beam profile measurements at modern ion synchrotrons and storage rings require high timing performances on a turn-by-turn basis. High spatial resolutions are essential for cold beams and beamwidth measurings. The currently used RGM supported very interesting measurements and applications. Due to the readout technology the spatial and time resolution is limited. To meet the expanded demands a more comprehensive device is under development. It will be an all-purpose residual gas monitor to cover the wide range of beam currents and transversal particle distributions. Due to the fast profile detection it will operate on primary electrons after residual gas ionization. A magnetic field of 100 mT binds them to the ionization point inside 0.1-mm orbits. The high-resolution mode will be read out by a digital CCD camera with an upstream MCP-phosphor screen assembly. It is planned to read out the fast turn-by-turn mode by an array of 100 photodiodes with a resolution of 1 mm. Every photodiode is equipped with an amplifier-digitizer device providing a frame rate of ∼ 10 MSamples/s

  9. Development of Residual Gas Profile Monitors at GSI

    Science.gov (United States)

    Giacomini, T.; Barabin, S.; Forck, P.; Liakin, D.; Skachkov, V.

    2004-11-01

    Beam profile measurements at modern ion synchrotrons and storage rings require high timing performances on a turn-by-turn basis. High spatial resolutions are essential for cold beams and beamwidth measurings. The currently used RGM supported very interesting measurements and applications. Due to the readout technology the spatial and time resolution is limited. To meet the expanded demands a more comprehensive device is under development. It will be an all-purpose residual gas monitor to cover the wide range of beam currents and transversal particle distributions. Due to the fast profile detection it will operate on primary electrons after residual gas ionization. A magnetic field of 100 mT binds them to the ionization point inside 0.1-mm orbits. The high-resolution mode will be read out by a digital CCD camera with an upstream MCP-phosphor screen assembly. It is planned to read out the fast turn-by-turn mode by an array of 100 photodiodes with a resolution of 1 mm. Every photodiode is equipped with an amplifier-digitizer device providing a frame rate of ˜ 10 MSamples/s.

  10. Noble Gas Measurement and Analysis Technique for Monitoring Reprocessing Facilities

    International Nuclear Information System (INIS)

    William S. Charlton

    1999-01-01

    An environmental monitoring technique using analysis of stable noble gas isotopic ratios on-stack at a reprocessing facility was developed. This technique integrates existing technologies to strengthen safeguards at reprocessing facilities. The isotopic ratios are measured using a mass spectrometry system and are compared to a database of calculated isotopic ratios using a Bayesian data analysis method to determine specific fuel parameters (e.g., burnup, fuel type, fuel age, etc.). These inferred parameters can be used by investigators to verify operator declarations. A user-friendly software application (named NOVA) was developed for the application of this technique. NOVA included a Visual Basic user interface coupling a Bayesian data analysis procedure to a reactor physics database (calculated using the Monteburns 3.01 code system). The integrated system (mass spectrometry, reactor modeling, and data analysis) was validated using on-stack measurements during the reprocessing of target fuel from a U.S. production reactor and gas samples from the processing of EBR-II fast breeder reactor driver fuel. These measurements led to an inferred burnup that matched the declared burnup with sufficient accuracy and consistency for most safeguards applications. The NOVA code was also tested using numerous light water reactor measurements from the literature. NOVA was capable of accurately determining spent fuel type, burnup, and fuel age for these experimental results. Work should continue to demonstrate the robustness of this system for production, power, and research reactor fuels

  11. Optical properties and composition changes in chromophoric dissolved organic matter along trophic gradients: Implications for monitoring and assessing lake eutrophication.

    Science.gov (United States)

    Zhang, Yunlin; Zhou, Yongqiang; Shi, Kun; Qin, Boqiang; Yao, Xiaolong; Zhang, Yibo

    2017-12-26

    Chromophoric dissolved organic matter (CDOM) is an important optically active substance in aquatic environments and plays a key role in light attenuation and in the carbon, nitrogen and phosphorus biogeochemical cycles. Although the optical properties, abundance, sources, cycles, compositions and remote sensing estimations of CDOM have been widely reported in different aquatic environments, little is known about the optical properties and composition changes in CDOM along trophic gradients. Therefore, we collected 821 samples from 22 lakes along a trophic gradient (oligotrophic to eutrophic) in China from 2004 to 2015 and determined the CDOM spectral absorption and nutrient concentrations. The total nitrogen (TN), total phosphorus (TP), and chlorophyll a (Chla) concentrations and the Secchi disk depth (SDD) ranged from 0.02 to 24.75 mg/L, 0.002-3.471 mg/L, 0.03-882.66 μg/L, and 0.05-17.30 m, respectively. The trophic state index (TSI) ranged from 1.55 to 98.91 and covered different trophic states, from oligotrophic to hyper-eutrophic. The CDOM absorption coefficient at 254 nm (a(254)) ranged from 1.68 to 92.65 m -1 . Additionally, the CDOM sources and composition parameters, including the spectral slope and relative molecular size value, exhibited a substantial variability from the oligotrophic level to other trophic levels. The natural logarithm value of the CDOM absorption, lna(254), is highly linearly correlated with the TSI (r 2  = 0.92, p 10 m -1 , respectively. The results suggested that the CDOM absorption coefficient a(254) might be a more sensitive single indicator of the trophic state than TN, TP, Chla and SDD. Therefore, we proposed a CDOM absorption coefficient and determined the threshold for defining the trophic state of a lake. Several advantages of measuring and estimating CDOM, including rapid experimental measurements, potential in situ optical sensor measurements and large-spatial-scale remote sensing estimations, make it

  12. Knowledge and understanding of dissolved solids in the Rio Grande–San Acacia, New Mexico, to Fort Quitman, Texas, and plan for future studies and monitoring

    Science.gov (United States)

    Moyer, Douglas; Anderholm, Scott K.; Hogan, James F.; Phillips, Fred M.; Hibbs, Barry J.; Witcher, James C.; Matherne, Anne Marie; Falk, Sarah E.

    2013-01-01

    indicated that (1) the inflow of saline groundwater, inflow of regional groundwater, and chemical reactions between mineral phases are the primary sources controlling dissolved solids in the Rio Grande, and (2) groundwater pumping and mineral precipitation are causing a net storage of dissolved solids in the Leasburg to El Paso and El Paso to Fort Quitman reaches of the Rio Grande. Looking forward, multiple water-resource managers from State and local agencies in New Mexico and Texas and Federal agencies formed the Rio Grande Salinity Management Coalition with the goal to reduce the amount of dissolved solids that are transported and stored in the Rio Grande study area. The recommendations for additional monitoring to assist the coalition are as follows:

  13. Monitoring soil greenhouse gas emissions from managed grasslands

    Science.gov (United States)

    Díaz-Pinés, Eugenio; Lu, Haiyan; Butterbach-Bahl, Klaus; Kiese, Ralf

    2014-05-01

    Grasslands in Central Europe are of enormous social, ecological and economical importance. They are intensively managed, but the influence of different common practices (i.e. fertilization, harvesting) on the total greenhouse gas budget of grasslands is not fully understood, yet. In addition, it is unknown how these ecosystems will react due to climate change. Increasing temperatures and changing precipitation will likely have an effect on productivity of grasslands and on bio-geo-chemical processes responsible for emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). In the frame of the TERENO Project (www.tereno.net), a long-term observatory has been implemented in the Ammer catchment, southern Germany. Acting as an in situ global change experiment, 36 big lysimeters (1 m2 section, 150 cm height) have been translocated along an altitudinal gradient, including three sites ranging from 600 to 860 meters above sea level. In addition, two treatments have been considered, corresponding to different management intensities. The overall aim of the pre-alpine TERENO observatory is improving our understanding of the consequences of climate change and management on productivity, greenhouse gas balance, soil nutritional status, nutrient leaching and hydrology of grasslands. Two of the sites are equipped with a fully automated measurement system in order to continuously and accurately monitor the soil-atmosphere greenhouse gas exchange. Thus, a stainless steel chamber (1 m2 section, 80 cm height) is controlled by a robotized system. The chamber is hanging on a metal structure which can move both vertically and horizontally, so that the chamber is able to be set onto each of the lysimeters placed on the field. Furthermore, the headspace of the chamber is connected with a gas tube to a Quantum Cascade Laser, which continuously measures CO2, CH4, N2O and H2O mixing ratios. The chamber acts as a static chamber and sets for 15 minutes onto each lysimeter

  14. Stitching Type Large Aperture Depolarizer for Gas Monitoring Imaging Spectrometer

    Science.gov (United States)

    Liu, X.; Li, M.; An, N.; Zhang, T.; Cao, G.; Cheng, S.

    2018-04-01

    To increase the accuracy of radiation measurement for gas monitoring imaging spectrometer, it is necessary to achieve high levels of depolarization of the incoming beam. The preferred method in space instrument is to introduce the depolarizer into the optical system. It is a combination device of birefringence crystal wedges. Limited to the actual diameter of the crystal, the traditional depolarizer cannot be used in the large aperture imaging spectrometer (greater than 100 mm). In this paper, a stitching type depolarizer is presented. The design theory and numerical calculation model for dual babinet depolarizer were built. As required radiometric accuracies of the imaging spectrometer with 250 mm × 46 mm aperture, a stitching type dual babinet depolarizer was design in detail. Based on designing the optimum structural parmeters the tolerance of wedge angle refractive index, and central thickness were given. The analysis results show that the maximum residual polarization degree of output light from depolarizer is less than 2 %. The design requirements of polarization sensitivity is satisfied.

  15. STITCHING TYPE LARGE APERTURE DEPOLARIZER FOR GAS MONITORING IMAGING SPECTROMETER

    Directory of Open Access Journals (Sweden)

    X. Liu

    2018-04-01

    Full Text Available To increase the accuracy of radiation measurement for gas monitoring imaging spectrometer, it is necessary to achieve high levels of depolarization of the incoming beam. The preferred method in space instrument is to introduce the depolarizer into the optical system. It is a combination device of birefringence crystal wedges. Limited to the actual diameter of the crystal, the traditional depolarizer cannot be used in the large aperture imaging spectrometer (greater than 100 mm. In this paper, a stitching type depolarizer is presented. The design theory and numerical calculation model for dual babinet depolarizer were built. As required radiometric accuracies of the imaging spectrometer with 250 mm × 46 mm aperture, a stitching type dual babinet depolarizer was design in detail. Based on designing the optimum structural parmeters,the tolerance of wedge angle,refractive index, and central thickness were given. The analysis results show that the maximum residual polarization degree of output light from depolarizer is less than 2 %. The design requirements of polarization sensitivity is satisfied.

  16. 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

  17. 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.

  18. KIGAM Seafloor Observation System (KISOS) for the baseline study in monitoring of gas hydrate test production in the Ulleung Basin, Korea

    Science.gov (United States)

    Lee, Sung-rock; Chun, Jong-hwa

    2013-04-01

    For the baseline study in the monitoring gas hydrate test production in the Ulleung Basin, Korea Institute of Geoscience and Mineral Resources (KIGAM) has developed the KIGAM Seafloor Observation System (KISOS) for seafloor exploration using unmanned remotely operated vehicle connected with a ship by a cable. The KISOS consists of a transponder of an acoustic positioning system (USBL), a bottom finding pinger, still camera, video camera, water sampler, and measuring devices (methane, oxygen, CTD, and turbidity sensors) mounted on the unmanned ROV, and a sediment collecting device collecting sediment on the seafloor. It is very important to monitoring the environmental risks (gas leakage and production water/drilling mud discharge) which may be occurred during the gas hydrate test production drilling. The KISOS will be applied to solely conduct baseline study with the KIGAM seafloor monitoring system (KIMOS) of the Korean gas hydrate program in the future. The large scale of environmental monitoring program includes the environmental impact assessment such as seafloor disturbance and subsidence, detection of methane gas leakage around well and cold seep, methane bubbles and dissolved methane, change of marine environments, chemical factor variation of water column and seabed, diffusion of drilling mud and production water, and biological factors of biodiversity and marine habitats before and after drilling test well and nearby areas. The design of the baseline survey will be determined based on the result of SIMAP simulation in 2013. The baseline survey will be performed to provide the gas leakage and production water/drilling mud discharge before and after gas hydrate test production. The field data of the baseline study will be evaluated by the simulation and verification of SIMAP simulator in 2014. In the presentation, the authors would like introduce the configuration of KISOS and applicability to the seafloor observation for the gas hydrate test production in

  19. Basic characteristics of hollow-filament polyimide membrane in gas separation and application to tritium monitors

    International Nuclear Information System (INIS)

    Sasaki, Sh.; Suzuki, T.; Kondo, K.; Tega, E.; Shimada, A.; Akahori, S.; Okuno, K.

    2003-01-01

    The separation efficiency of hollow-filament polyimide membranes for 3 H and 41 Ar is preliminarily examined for a potential application to continuous gas monitoring systems for analysis of stack emission from accelerator facilities. The basic gas separation characteristics of the membranes are experimentally investigated, and a preliminary gas monitor design is proposed. The membranes are capable of selectively enriching hydrogen by more than 25 times, with negligible variation with respect to the species of isotope. (author)

  20. Leakage detection of Marcellus Shale natural gas at an Upper Devonian gas monitoring well: a 3-d numerical modeling approach.

    Science.gov (United States)

    Zhang, Liwei; Anderson, Nicole; Dilmore, Robert; Soeder, Daniel J; Bromhal, Grant

    2014-09-16

    Potential natural gas leakage into shallow, overlying formations and aquifers from Marcellus Shale gas drilling operations is a public concern. However, before natural gas could reach underground sources of drinking water (USDW), it must pass through several geologic formations. Tracer and pressure monitoring in formations overlying the Marcellus could help detect natural gas leakage at hydraulic fracturing sites before it reaches USDW. In this study, a numerical simulation code (TOUGH 2) was used to investigate the potential for detecting leaking natural gas in such an overlying geologic formation. The modeled zone was based on a gas field in Greene County, Pennsylvania, undergoing production activities. The model assumed, hypothetically, that methane (CH4), the primary component of natural gas, with some tracer, was leaking around an existing well between the Marcellus Shale and the shallower and lower-pressure Bradford Formation. The leaky well was located 170 m away from a monitoring well, in the Bradford Formation. A simulation study was performed to determine how quickly the tracer monitoring could detect a leak of a known size. Using some typical parameters for the Bradford Formation, model results showed that a detectable tracer volume fraction of 2.0 × 10(-15) would be noted at the monitoring well in 9.8 years. The most rapid detection of tracer for the leak rates simulated was 81 days, but this scenario required that the leakage release point was at the same depth as the perforation zone of the monitoring well and the zones above and below the perforation zone had low permeability, which created a preferred tracer migration pathway along the perforation zone. Sensitivity analysis indicated that the time needed to detect CH4 leakage at the monitoring well was very sensitive to changes in the thickness of the high-permeability zone, CH4 leaking rate, and production rate of the monitoring well.

  1. Geopressured-geothermal test of the EDNA Delcambre No. 1 well, Tigre Lagoon Field, Vermilion Parish, Louisiana: analysis of water an dissolved natural gas. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hankins, B.E.; Karkalits, O.C.

    1978-09-01

    The Edna Delcambre et al. No. 1 gas well, shut-in since June 1975, was made available for the project. Two geopressured sand-bed aquifers were tested: sand No. 3 at a depth of 12,900 feet and sand No. 1 at a depth of 12,600 feet. Each aquifer was subjected to flow tests which lasted approximately three weeks in each case. Water samples were obtained during flow testing of the two geopressured aquifers. The water contained 11.3 to 13.3% dissolved solids. Several radioactive species were measured. Radium-226 was found to be approximately 10 times more concentrated than the average amount observed in surface waters. No appreciable amount of heavy metals was detected. Recombination studies at bottom-hole conditions indicate the solubility of natural gas per barrel of water to be about 24 SCF. The methane content was 93 to 95%, and the gas had a heating value in the range of 1020 to 1070 Btu/cu.ft. During the flow tests, the gas/water ratio at the well-head was observed to be 45 to 88 SCF/Bbl water produced. (MHR)

  2. Method and apparatus for continuously detecting and monitoring the hydrocarbon dew-point of gas

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, G.J.; Pritchard, F.R.

    1987-08-04

    This patent describes a method and apparatus for continuously detecting and monitoring the hydrocarbon dew-point of a gas. A gas sample is supplied to a dew-point detector and the temperature of a portion of the sample gas stream to be investigated is lowered progressively prior to detection until the dew-point is reached. The presence of condensate within the flowing gas is detected and subsequently the supply gas sample is heated to above the dew-point. The procedure of cooling and heating the gas stream continuously in a cyclical manner is repeated.

  3. The generalized model of organization and planning of regional gas supply monitoring

    Directory of Open Access Journals (Sweden)

    Maria V. Shevchenko

    2015-12-01

    Full Text Available At the moment, gas is one of the most promising types of fuel in Ukraine. In this regard, the problems associated with its transportation in the regional system of gas supply are relevant. Now it is not completely solved and needs detailed study the problem of monitoring the regional gas supply system. Aim: The aim of the study is to improve the efficiency of the regional gas supply system at the expense of the organization and planning of gas transport monitoring and, in the future, the synthesis of the monitoring system of regional gas supply. Materials and Methods: The generalized model of organization and planning of monitoring regional gas suppliers were developed to achieve this goal. It allows making decisions on the organization of the monitoring system. In addition, this model makes it possible to plan under conditions of multicriteriality and uncertainty of the source data. Results: The basic criteria and constraints for solving the problem of organizing and planning the monitoring system of regional gas supply are proposed in this work. The corresponding computations were made to confirm the assumptions. The calculations were carried out in context of uncertainty of input data using a set of methods for the analysis of hierarchies, exhaustive search, as well as the methods of decision making in context of uncertainty.

  4. Absorption and fluorescence properties of chromophoric dissolved organic matter: implications for the monitoring of water quality in a large subtropical reservoir.

    Science.gov (United States)

    Liu, Xiaohan; Zhang, Yunlin; Shi, Kun; Zhu, Guangwei; Xu, Hai; Zhu, Mengyuan

    2014-12-01

    The development of techniques for real-time monitoring of water quality is of great importance for effectively managing inland water resources. In this study, we first analyzed the absorption and fluorescence properties in a large subtropical reservoir and then used a chromophoric dissolved organic matter (CDOM) fluorescence monitoring sensor to predict several water quality parameters including the total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD), dissolved organic carbon (DOC), and CDOM fluorescence parallel factor analysis (PARAFAC) components in the reservoir. The CDOM absorption coefficient at 254 nm (a(254)), the humic-like component (C1), and the tryptophan-like component (C3) decreased significantly along a gradient from the northwest to the lake center, northeast, southwest, and southeast region in the reservoir. However, no significant spatial difference was found for the tyrosine-like component (C2), which contributed only four marked peaks. A highly significant linear correlation was found between the a(254) and CDOM concentration measured using the CDOM fluorescence sensor (r(2) = 0.865, n = 76, p CDOM concentrations could act as a proxy for the CDOM absorption coefficient measured in the laboratory. Significant correlations were also found between the CDOM concentration and TN, TP, COD, DOC, and the maximum fluorescence intensity of C1, suggesting that the real-time monitoring of CDOM concentrations could be used to predict these water quality parameters and trace the humic-like fluorescence substance in clear aquatic ecosystems with DOC CDOM fluorescence sensor is a useful tool for on-line water quality monitoring if the empirical relationship between the CDOM concentration measured using the CDOM fluorescence sensor and the water quality parameters is calibrated and validated.

  5. Long-term autonomous volcanic gas monitoring with Multi-GAS at Mount St. Helens, Washington, and Augustine Volcano, Alaska

    Science.gov (United States)

    Kelly, P. J.; Ketner, D. M.; Kern, C.; Lahusen, R. G.; Lockett, C.; Parker, T.; Paskievitch, J.; Pauk, B.; Rinehart, A.; Werner, C. A.

    2015-12-01

    In recent years, the USGS Volcano Hazards Program has worked to implement continuous real-time in situ volcanic gas monitoring at volcanoes in the Cascade Range and Alaska. The main goal of this ongoing effort is to better link the compositions of volcanic gases to other real-time monitoring data, such as seismicity and deformation, in order to improve baseline monitoring and early detection of volcanic unrest. Due to the remote and difficult-to-access nature of volcanic-gas monitoring sites in the Cascades and Alaska, we developed Multi-GAS instruments that can operate unattended for long periods of time with minimal direct maintenance from field personnel. Our Multi-GAS stations measure H2O, CO2, SO2, and H2S gas concentrations, are comprised entirely of commercial off-the-shelf components, and are powered by small solar energy systems. One notable feature of our Multi-GAS stations is that they include a unique capability to perform automated CO2, SO2, and H2S sensor verifications using portable gas standards while deployed in the field, thereby allowing for rigorous tracking of sensor performances. In addition, we have developed novel onboard data-processing routines that allow diagnostic and monitoring data - including gas ratios (e.g. CO2/SO2) - to be streamed in real time to internal observatory and public web pages without user input. Here we present over one year of continuous data from a permanent Multi-GAS station installed in August 2014 in the crater of Mount St. Helens, Washington, and several months of data from a station installed near the summit of Augustine Volcano, Alaska in June 2015. Data from the Mount St. Helens Multi-GAS station has been streaming to a public USGS site since early 2015, a first for a permanent Multi-GAS site. Neither station has detected significant changes in gas concentrations or compositions since they were installed, consistent with low levels of seismicity and deformation.

  6. Development of residual gas ionization profile monitor for high intensity proton beams

    CERN Document Server

    Sato, Y; Hirose, E; Ieiri, M; Igarashi, Y; Inaba, S; Katoh, Y; Minakawa, M; Noumi, H; Saitó, M; Suzuki, Y; Takahashi, H; Takasaki, M; Tanaka, K; Toyoda, A; Yamada, Y; Yamanoi, Y; Watanabe, H

    2006-01-01

    Nondestructive beam profile monitor utilizing ionizations of residual gas has been developed for continuous monitoring of 3?0(J-PARC). Knock-on electrons produced in the ionizations of residual gas vacuumed to 1 Pa are collected with a uniform electric field applied between electrodes. Applying a uniform electric field parallel to the electric field is essential to reduce diffusion of electrons crossing over magnetic flux. A prototype monitor has been constructed and installed in EP2-C beam line at KEK 12 GeV proton synchrotron (12 Ge V-PS). The profiles measured with the present monitor agree with the ones measured with the existing destructive profile monitor. The present monitor shows sufficient performances as a candidate of the profile monitor at J-PARC. In the present article, the working principle of the present monitor, the results of test experiments, and further developments are described in detail.

  7. A simple and rapid gas chromatographic method for the determination of dissolved deuterium and nitrogen in heavy water coolant of a nuclear reactor

    International Nuclear Information System (INIS)

    Nair, B.K.S.

    1976-01-01

    A known volume of a heavy water sample is equilibrated with a known volume of pure helium gas at atmospheric pressure in a sample tube. The dissolved gases evolve into the helium and distribute themselves between the gaseous and liquid phases according to their equilibrium partial pressures. These partial pressures of the gases in the equilibrium gas mixture are determined by analysing it gas-chromatographically. From these analytical data and the absorption coefficients of deuterium and nitrogen, their original concentrations in heavy water are calculated. Corrections for the increase in the total pressure of the gaseous phase owing to evolved gases are calculated and found to be negligible. Air contamination during sampling and analysis can be detected by the presence of the oxygen peak in the chromatogram and corrected for. The calculation is facilitated by programming it on an electronic calculator. The method is much simpler and faster than the vacuum method usually applied for this analysis. One determination can be completed in about an hour. The average deviation and standard deviation have been estimated at 0.19 ml/litre heavy water and 0.25 ml/litre heavy water respectively in deuterium, and 0.36 and 0.68 ml/litre in nitrogen. (author)

  8. Monitoring Marcellus: A Case Study of a Collaborative Volunteer Monitoring Project to Document the Impact of Unconventional Shale Gas Extraction on Small Streams

    Directory of Open Access Journals (Sweden)

    Candie C. Wilderman

    2016-05-01

    Full Text Available The rapid growth of the natural gas extraction industry in Pennsylvania and neighboring states has stirred concerned citizens to seek ways to collect data on water quality impacts from the extraction activities. As a response to requests from community members, the Alliance for Aquatic Resource Monitoring (ALLARM developed a volunteer-friendly protocol in 2010 for early detection and reporting of surface water contamination by shale gas extraction activities in small streams. To date, ALLARM has trained more than 2,000 volunteers in Pennsylvania, New York, and West Virginia to monitor water quality (conductivity, barium, strontium, and total dissolved solids and physical parameters (stream stage and visual observations prior to, during, and after shale gas wells have been developed. This paper documents the operational models of Public Participation in Scientific Research (PPSR used by ALLARM, describes the volunteer monitoring protocol developed, and examines three years of water quality results from hundreds of monitoring sites in Pennsylvania and New York. The majority of watersheds monitored are small, forested, headwater streams. Results indicate that mean conductivity in streams is strongly and positively related to the percentage of development and the percentage of limestone in the watersheds. Mean conductivity is not significantly related to number or density of drilled wells, although the dataset did not lend itself to finding a signal from shale gas activities because only 20% of the watersheds had wells drilled at the time of sampling. This fact enables the use of these data as baseline data for future documentation of shale gas impacts on water quality. Volunteers have reported multiple cases of visual pollution related to shale gas activities, but have not identified water contamination events based on stream water chemistry. The results of the volunteer dataset are compared with results from the scientific literature, affirming

  9. A continuous flow isotope ratio mass spectrometry method for high precision determination of dissolved gas ratios and isotopic composition

    DEFF Research Database (Denmark)

    Charoenpong, C. N.; Bristow, L. A.; Altabet, M. A.

    2014-01-01

    ratio mass spectrometer (IRMS). A continuous flow of He carrier gas completely degasses the sample, and passes through the preparation and purification system before entering the IRMS for analysis. The use of this continuous He carrier permits short analysis times (less than 8 min per sample......) as compared with current high-precision methods. In addition to reference gases, calibration is achieved using air-equilibrated water standards of known temperature and salinity. Assessment of reference gas injections, air equilibrated standards, as well as samples collected in the field shows the accuracy...

  10. FFTF fuel failure detection and characterization by cover gas monitoring. Final report

    International Nuclear Information System (INIS)

    Miller, W.C.; Holt, F.E.

    1977-01-01

    The Fast Flux Test Facility (FFTF) will include a Fuel Failure Monitoring (FFM) System designed to detect, characterize, and locate fuel and absorber pin failures (i.e., cladding breaches) using a combination of delayed neutron detection, cover gas radioisotope monitoring, and gas tagging. During the past several years the Hanford Engineering Development Laboratory has been involved in the development, design, procurement, and installation of this integrated system. The paper describes one portion of the FFM System, the Cover Gas Monitoring System (CGMS), which has the primary function of fuel failure detection and characterization in the FFTF. By monitoring the various radioisotopes in the cover gas, the CGMS will both detect fuel and absorber pin failures and characterize those failures as to magnitude and severity

  11. Water quality monitoring in a bathing area of Civitavecchia (Latium, Italy) using Chromophoric Dissolved Organic Matter (CDOM) as a tracer of faecal contamination

    Science.gov (United States)

    Madonia, Alice; Bonamano, Simone; Caruso, Gabriella; Stefani', Chiara; Consalvi, Natalizia; Piermattei, Viviana; Zappalà, Giuseppe; Marcelli, Marco

    2017-04-01

    Coastal urban bathing areas are often affected by events of faecal contamination, caused by the discharge of untreated wastewaters during the bathing season that can increase the risk for public health. Monitoring the quality of recreational waters is still closely linked to time-consuming seawater sampling and laboratory analysis, not allowing promptly management interventions. To face this issue, the European environmental policies strongly promote the development of coastal observing systems, above all in the Southern European Seas (SES). Chromophoric Dissolved Organic Matter (CDOM) has been increasingly used as a tracer of bacterial loads, since wastewaters are characterized by a large amount of organic compounds. The aim of this work was to study the relation between CDOM and Escherichia coli abundance, giving relevance to bacterial physiological state detected using both the standard culture method and the innovative fluorescent antibody technique. Attention has been paid also on the expression of extracellular enzymatic activity by the total microbial community to explore the role of bacteria in the decomposition processes of dissolved organic matter. Data were collected during summer 2015 and 2016 in a bathing area of Civitavecchia at increasing distances from the discharge point. The results confirm the usefulness of CDOM measurements as a proxy of faecal pollution in bathing areas. In this perspective, the low-cost stand-alone systems equipped with CDOM fluorescence sensors developed by the Laboratory of Experimental Oceanology and Marine Ecology (Tuscia University) (Marcelli et al., 2014) could allow the continous monitoring of water quality, increasing the capabilities of the Civitavecchia Coastal Environmental Monitoring System (C-CEMS) in the analysis of pollution events. Thanks to the integration of in situ fixed stations, high-resolution satellites imagery and numerical models, C-CEMS provides a management tool to support the stakeholders for timely

  12. Dissolved radon and uranium in groundwater in a potential coal seam gas development region (Richmond River Catchment, Australia).

    Science.gov (United States)

    Atkins, Marnie L; Santos, Isaac R; Perkins, Anita; Maher, Damien T

    2016-04-01

    The extraction of unconventional gas resources such as shale and coal seam gas (CSG) is rapidly expanding globally and often prevents the opportunity for comprehensive baseline groundwater investigations prior to drilling. Unconventional gas extraction often targets geological layers with high naturally occurring radioactive materials (NORM) and extraction practices may possibly mobilise radionuclides into regional and local drinking water resources. Here, we establish baseline groundwater radon and uranium levels in shallow aquifers overlying a potential CSG target formation in the Richmond River Catchment, Australia. A total of 91 groundwater samples from six different geological units showed highly variable radon activities (0.14-20.33 Bq/L) and uranium levels (0.001-2.77 μg/L) which were well below the Australian Drinking Water Guideline values (radon; 100 Bq/L and uranium; 17 μg/L). Therefore, from a radon and uranium perspective, the regional groundwater does not pose health risks to consumers. Uranium could not explain the distribution of radon in groundwater. Relatively high radon activities (7.88 ± 0.83 Bq/L) in the fractured Lismore Basalt aquifer coincided with very low uranium concentrations (0.04 ± 0.02 μg/L). In the Quaternary Sediments aquifers, a positive correlation between U and HCO3(-) (r(2) = 0.49, p uranium was present as uranyl-carbonate complexes. Since NORM are often enriched in target geological formations containing unconventional gas, establishing radon and uranium concentrations in overlying aquifers comprises an important component of baseline groundwater investigations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. I-129, Kr-85, C-14 and NO/sub x/ removal from spent fuel dissolver off-gas at atmospheric pressure and at reduced off-gas flow

    International Nuclear Information System (INIS)

    Henrich, E.; Huefner, R.

    1981-01-01

    A dissolver off-gas (DOG) system suitable for a LWR, FBR or HTR spent fuel reprocessing plant is described, incorporating the following features: (1) the DOG flow is reduced to a reasonably small volume, using fumeless dissolution conditions, by maintaining high concentrations, the retention procedures are simplified and accompanied by an economic reduction of the equipment size; (2) all process operations are conducted at atmospheric or subatmospheric pressure, including noble gas removal by selective absorption, without using high temperature processes; (3) all processes, except HEPA filtering, are continuous and do not accumulate large amounts of waste nuclides, the DOG process sequence is mutually compatible with itself and with processing in the headend, showing on-line redundancy for the removal of the most radiotoxic nuclides; and (4) the DOG system only deviates slightly from proven technology. The stage of development and relevant results are given both for a lab. scale and a pilot plant scale

  14. High Resolution CH4 Emissions and Dissolved CH4 Measurements Elucidate Surface Gas Exchange Processes in Toolik Lake, Arctic Alaska

    Science.gov (United States)

    Del Sontro, T.; Sollberger, S.; Kling, G. W.; Shaver, G. R.; Eugster, W.

    2013-12-01

    Approximately 14% of the Alaskan North Slope is covered in lakes of various sizes and depths. Diffusive carbon emissions (CH4 and CO2) from these lakes offset the tundra sink by ~20 %, but the offset would substantially increase if ebullitive CH4 emissions were also considered. Ultimately, arctic lake CH4 emissions are not insignificant in the global CH4 budget and their contribution is bound to increase due to impacts from climate change. Here we present high resolution CH4 emission data as measured via eddy covariance and a Los Gatos gas analyzer during the ice free period from Toolik Lake, a deep (20 m) Arctic lake located on the Alaskan North Slope, over the last few summers. Emissions are relatively low (Gatos gas analyzer. Thus, having both the flux and the CH4 gradient across the air-water interface measured directly, we can calculate k and investigate the processes influencing CH4 gas exchange in this lake. Preliminary results indicate that there are two regimes in wind speed that impact k - one at low wind speeds up to ~5 m s-1 and another at higher wind speeds (max ~10 m s-1). The differential wind speeds during night and day may compound the effect of convective mixing and cause the diurnal variation in observed fluxes.

  15. Diode Laser Raman Scattering Prototype Gas-Phase Environmental Monitoring

    National Research Council Canada - National Science Library

    Benner, Robert

    1999-01-01

    We proposed developing a diode-laser-based, full spectrum Raman scattering instrument incorporating a multipass, external cavity enhancement cell for full spectrum, gas phase analysis of environmental pollutants...

  16. Monitor consumers market electricity and natural gas 2010

    International Nuclear Information System (INIS)

    Schalm, T.; Cordeweners, J.; Noorlander, M.; Kahl, E.

    2011-02-01

    This monitor maps the developments in the energy market for small users (consumers). It can be used to identify possible bottlenecks in this market. The monitoring report describes the energy market for consumers by means of six indicators that are relevant for the operation of the market: demand for products, prices, access and concentration, switching, transparency and service provision. [nl

  17. N2 gas station and gas distribution system for TLD personnel monitoring gas based semi-automatic badge readers

    International Nuclear Information System (INIS)

    Chourasiya, G.; Pradhan, S.M.; Kher, R.K.; Bhatt, B.C

    2003-01-01

    Full text: New improvised hot gas based Auto TLD badge reader has several advantages over the earlier contact heating based manual badge reader. It requires constant supply of N 2 gas for its operation; The gas supplied using replaceable individual gas cylinders may have some safety hazards in their handling. It was therefore considered worthwhile to setup a N 2 gas assembly/ station outside the lab area and to bring regulated gas supply through network of tubes with proper regulation to the individual readers. The paper presents detailed description of the gas station and distribution system. The system is quite useful and offers several practical advantages for readout of TLD badges on the semiautomatic badge readers based on gas heating. Important advantage from dosimetric point of view is avoidance of gas flow rate fluctuations and corresponding variations in TL readouts

  18. Quantitative monitoring of gas flooding in oil-bearing reservoirs using a pulsed neutron tool

    International Nuclear Information System (INIS)

    Ruhovets, N.; Wyatt, D.F. Jr.

    1991-01-01

    This paper reports on quantitative monitoring of gas flooding in oil bearing reservoirs which is unique in that saturations of three fluids (gas, oil and water) in the effective pore space have to be determined, while in most other applications saturation behind casing is determined only for two fluids: hydrocarbons and water. A new method has been developed to monitor gas flooding of oil reservoirs. The method is based on computing two porosities: true effective (base) porosity determined before gas flooding, and apparent effective (monitor) porosity determined after gas flooding. The base porosity is determined from open and/or cased hole porosity logs run before the flooding. When open hole logs are available, the cased hole porosity logs are calibrated against open hole log. The monitor porosity is determined from one of the cased hole porosity logs, such as a neutron log or count rate ratio curve from a pulsed neutron log run after the gas flooding. The base and monitor porosities provide determination of the hydrogen index of the reservoir fluid after the flooding. This hydrogen index is then used to determine saturation of the flood agent after flooding. Water saturation after flooding can be determined from the equation which relates neutron total cross section (Σm) to volumetric constituent cross sections, using Σm values from a monitor run (after flooding)

  19. Impurity of Sulfur Layers and Magmatic Gas Scrubbing: Implications for Gas Monitoring

    Science.gov (United States)

    Scolamacchia, T.

    2017-12-01

    The evidence of bodies of elemental sulfur (Se) beneath acid crater lakes at the summit of composite active volcanoes has been recognized several decades ago (Oppenheimer and Stevenson, 1989; Christenson and Woods, 1993). But Se accumulation was already hypothesized a century ago at Kusatzu Shirane (Japan) based on the observation of sulfur spherules floating on its crater-lake (Ohashi, 1919). Since these pioneering works, other studies have focused on understanding key aspects of molten sulfur bodies, considered a feature unique of volcanic lakes. Instead, it is reasonable to assume that Se bodies occur in several volcanic settings because a) several reactions may lead to Se deposition from S-bearing gases, and b) crater-lakes, surface expressions of hydrothermal systems, are transient features. The scrubbing of several magmatic gases, some of which critical for volcano monitoring, has been attributed to ground/surface waters (Symonds et al. 2001). Nevertheless, gas scrubbing could reflect viscosity variations of impure Se within hydrothermal systems. Industrial experiments indicated that impurities (organics, H2S, ammonia, HCl, HF, HBr, HI) hinder Se polymerization at T ≥ 160ºC, allowing viscosity to remain low for long time depending on the maximum T achieved and heating rates (Bacon and Fanelli, 1943). However, a prolonged heating destroys the viscosity-modifying substances (e.g. H2Sx formed by reactions with organics, H2S, or ammonia) and dramatic Se viscosity increases occur after a certain number of heating and cooling cycles. A prolonged boiling of Se with organics was observed to release H2S, following H2Sx disruption. Some gases (e.g. SO2) do not affect Se viscosity. In volcanic environments gases such as SO2, CO2 could escape under Selow viscosity regimes. Also, halogens absence in gas emissions could be caused by their participation in reactions within S-layers causing its viscosity to remain low. More data are needed to validate the hypothesis

  20. 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)

  1. Continuous CO2 gas monitoring to clarify natural pattern and artificial leakage signals

    Science.gov (United States)

    Joun, W.; Ha, S. W.; Joo, Y. J.; Lee, S. S.; Lee, K. K.

    2017-12-01

    Continuous CO2 gas monitoring at shallow aquifer is significant for early detection and immediate handling of an aquifer impacted by leaking CO2 gas from the sequestration reservoir. However, it is difficult to decide the origin of CO2 gas because detected CO2 includes not only leaked CO2 but also naturally emitted CO2. We performed CO2 injection and monitoring tests in a shallow aquifer. Before the injection of CO2 infused water, we have conducted continuous monitoring of multi-level soil CO2 gas concentration and physical parameters such as temperature, humidity, pressure, wind speed and direction, and precipitation. The monitoring data represented that CO2 gas concentrations in unsaturated soil zone borehole showed differences at depths and daily variation (360 to 6980 ppm volume). Based on the observed data at 5 m and 8 m depths, vertical flux of gas was calculated as 0.471 L/min (LPM) for inflow from 5 m to 8 m and 9.42E-2 LPM for outflow from 8 m to 5 m. The numerical and analytical models were used to calculate the vertical flux of gas and to compare with observations. The results showed that pressure-based modeling could not explain the rapid change of CO2 gas concentration in borehole. Acknowledgement Financial support was provided by the "R&D Project on Environmental Management of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003)

  2. Sensitivity and environmental response of the CMS RPC gas gain monitoring system

    CERN Document Server

    Benussi, L.; Colafranceschi, S.; Fabbri, F.L.; Giardoni, M.; Ortenzi, B.; Paolozzi, A.; Passamonti, L.; Pierluigi, D.; Ponzio, B.; Russo, A.; Colaleo, A.; Loddo, F.; Maggi, M.; Ranieri, A.; Abbrescia, M.; Iaselli, G.; Marangelli, B.; Natali, S.; Nuzzo, S.; Pugliese, G.; Romano, F.; Roselli, G.; Trentadue, R.; Tupputi, S.; Guida, R.; Polese, G.; Sharma, A.; Cimmino, A.; Lomidze, D.; Paolucci, D.; Piccolo, P.; Baesso, P.; Necchi, M.; Pagano, D.; Ratti, S.P.; Vitulo, P.; Viviani, C.

    Results from the gas gain monitoring (GGM) system for the muon detector using RPC in the CMS experiment at the LHC is presented. The system is designed to provide fast and accurate determination of any shift in the working point of the chambers due to gas mixture changes.

  3. Concentration and flux of total and dissolved phosphorus, total nitrogen, chloride, and total suspended solids for monitored tributaries of Lake Champlain, 1990-2012

    Science.gov (United States)

    Medalie, Laura

    2014-01-01

    Annual and daily concentrations and fluxes of total and dissolved phosphorus, total nitrogen, chloride, and total suspended solids were estimated for 18 monitored tributaries to Lake Champlain by using the Weighted Regressions on Time, Discharge, and Seasons regression model. Estimates were made for 21 or 23 years, depending on data availability, for the purpose of providing timely and accessible summary reports as stipulated in the 2010 update to the Lake Champlain “Opportunities for Action” management plan. Estimates of concentration and flux were provided for each tributary based on (1) observed daily discharges and (2) a flow-normalizing procedure, which removed the random fluctuations of climate-related variability. The flux bias statistic, an indicator of the ability of the Weighted Regressions on Time, Discharge, and Season regression models to provide accurate representations of flux, showed acceptable bias (less than ±10 percent) for 68 out of 72 models for total and dissolved phosphorus, total nitrogen, and chloride. Six out of 18 models for total suspended solids had moderate bias (between 10 and 30 percent), an expected result given the frequently nonlinear relation between total suspended solids and discharge. One model for total suspended solids with a very high bias was influenced by a single extreme value; however, removal of that value, although reducing the bias substantially, had little effect on annual fluxes.

  4. Runoff load estimation of particulate and dissolved nitrogen in Lake Inba watershed using continuous monitoring data on turbidity and electric conductivity.

    Science.gov (United States)

    Kim, J; Nagano, Y; Furumai, H

    2012-01-01

    Easy-to-measure surrogate parameters for water quality indicators are needed for real time monitoring as well as for generating data for model calibration and validation. In this study, a novel linear regression model for estimating total nitrogen (TN) based on two surrogate parameters is proposed based on evaluation of pollutant loads flowing into a eutrophic lake. Based on their runoff characteristics during wet weather, electric conductivity (EC) and turbidity were selected as surrogates for particulate nitrogen (PN) and dissolved nitrogen (DN), respectively. Strong linear relationships were established between PN and turbidity and DN and EC, and both models subsequently combined for estimation of TN. This model was evaluated by comparison of estimated and observed TN runoff loads during rainfall events. This analysis showed that turbidity and EC are viable surrogates for PN and DN, respectively, and that the linear regression model for TN concentration was successful in estimating TN runoff loads during rainfall events and also under dry weather conditions.

  5. Fiber optic gas detection system for health monitoring of oil-filled transformer

    Science.gov (United States)

    Ho, H. L.; Ju, J.; Jin, W.

    2009-10-01

    This paper reports the development of a fiber-optic gas detection system capable of detecting three types of dissolved fault gases in oil-filled power transformers or equipment. The system is based on absorption spectroscopy and the target gases include acetylene (C2H2), methane (CH4) and ethylene (C2H4). Low-cost multi-pass sensor heads using fiber coupled micro-optic cells are employed for which the interaction length is up to 4m. Also, reference gas cells made of photonic bandgap (PBG) fiber are implemented. The minimum detectable gas concentrations for methane, acetylene and ethylene are 5ppm, 2ppm and 50ppm respectively.

  6. Development of gas-sampling device for 13N monitoring system

    International Nuclear Information System (INIS)

    Zhao Lihong; Gong Xueyu

    2003-01-01

    The 13 N monitoring system is used in the monitoring of the rate of leakage of the primary coolant circuit in nuclear power stations. The author introduces a gas-sampling device of the 13 Nmonitoring system. It is with a close-loop flow control system with intelligent control of Single Chip Micyoco (SCM), and has the ability to monitor and replace the filter paper automatically, to increase the automation of the device and stable operation in long time

  7. Applications of ZigBee Technology in the Safety Monitoring System of Low Gas Pipeline Transportation

    Directory of Open Access Journals (Sweden)

    Wei Deyu

    2015-01-01

    Full Text Available The existing safety monitoring system of low gas pipeline transportation establishes a wired communication network monitoring system mainly on the basis of industrial bus. It has problems such as large transmission signal attenuation, complex wiring, high-labor intensity, inconvenient installation and maintenance, high maintenance cost, and so on. Featuring low cost, power-saving, reliability, stability and flexibility, the wireless sensor network established by ZigBee wireless communication technology can realize the real-time all-dimensional dynamic monitoring on parameters of low gas pipeline transportation system and overcome the shortcomings and deficiencies of wired network system.

  8. Monitoring of trace chloride ions at different stages of the gas production process

    Directory of Open Access Journals (Sweden)

    A.Y. El Naggar

    2015-01-01

    Full Text Available Fifty gas and liquid samples at different stages of Obaiyed gas plant in Egypt were selected and subjected for determining chloride ion and hydrocarbon compositions. The trace levels of chloride in the water extracted from natural gas, condensate, Benfield and glycol samples were achieved using ion chromatograph (IC, electrical, conductivity and potentiometric methods, respectively. The hydrocarbon compositions were analyzed and evaluated using capillary gas chromatography. The chloride ions in natural gas and condensate are a function of water content and their concentration mainly depends on the separation efficiency. Variability in natural gas and condensate compositions seasonally is not an uncommon occurrence. Our aim is monitoring of chloride ion to select and optimize the conditions of sweetening and dehydration regenerators in order to follow and prevent their gradient in gas plant.

  9. Gas dynamics considerations in a non-invasive profile monitor for charged particle beams

    CERN Document Server

    Tzoganis, Vasilis; Welsch, Carsten P

    2014-01-01

    A non-invasive, gas jet-based, beam profile monitor has been developed in the QUASAR Group at the Cockcroft Institute, UK. This allows on-line measurement of the 2-dimensional transverse profile of particle beams with negligible disturbance to either primary beam or accelerator vacuum. The monitor is suitable for use with beams across a wide range of energies and intensities. In this setup a nozzle-skimmer system shapes a thin supersonic gas jet into a curtain. However, the small dimensions of the gas inlet nozzle and subsequent skimmers were shown to be the cause of many operational problems. In this paper, the dynamics of gas jet formation transport and shaping is discussed before an image-processing based alignment technique is introduced. Furthermore, experimental results obtained with a 5 keV electron beam are discussed and the effects of gas stagnation pressure on the acquired beam are presented.

  10. Calibration method based on direct radioactivity measurement for radioactive gas monitoring instruments

    International Nuclear Information System (INIS)

    Yoshida, Makoto; Ohi, Yoshihiro; Chida, Tohru; Wu, Youyang.

    1993-01-01

    A calibration method for radioactive gas monitoring instruments was studied. In the method, gaseous radioactivity standards were provided on the basis of the direct radioactivity measurement by the diffusion-in long proportional counter method (DLPC method). The radioactivity concentration of the gas mixture through a monitoring instrument was determined by sampling the known volume of the gas mixture into the proportional counter used for the DLPC method. Since oxygen in the gas mixture decreased the counting efficiency in a proportional counter, the influence on calibration was experimentally estimated. It was not serious and able to be easily corrected. By the present method, the relation between radioactivity concentration and ionization current was determined for a gas-flow ionization chamber with 1.5 l effective volume. It showed good agreement with the results in other works. (author)

  11. Laboratory Connections--Gas Monitoring Transducers Part III: Combustible Gas Sensors.

    Science.gov (United States)

    Powers, Michael H.; Dahman, Doug

    1989-01-01

    Describes an interface that uses semiconductor metal oxides to detect low gas concentrations. Notes the detector has long life, high stability, good reproducibility, low cost, and is able to convert the gas concentration to an electrical signal with a simple circuit. Theory, schematic, and applications are provided. (MVL)

  12. Noble gas atmospheric monitoring for international safeguards at reprocessing plants

    International Nuclear Information System (INIS)

    Nakhleh, C.W.; Poths, J.; Stanbro, W.D.; Perry, R.T. Jr.; Wilson, W.B.; Fearey, B.L.

    1997-01-01

    The use of environmental sampling is a major component of the improvements of International Atomic Energy Agency safeguards being carried out under Program 93+2. Nonradioactive noble gas isotopic measurements in the effluent stream of large reprocessing facilities may provide useful confirmatory information on the burnup and reactor type of the spent fuel undergoing reprocessing. The authors have taken and analyzed stack samples at an operating facility. The data show clear fission signals. The authors are currently applying a maximum-likelihood estimation procedure to determine the fuel burnup from these data. They anticipate that the general features involved in the table noble gas problem--selection of appropriate signals, measurement of those signals under realistic conditions, and inverse calculation of parameters of interest from the environmental data--will be present in all environmental sampling problems. These methods should therefore be widely applicable

  13. Portable Mass Spectrometer Applications for In Situ Environmental Gas Monitoring

    Science.gov (United States)

    Griffin, Timothy P.; Diaz, J. Andres; Arkin, C. Richard; Conejo, Elian

    2005-01-01

    Primary Goal of this project is to (1) Design/build a flexible system to monitor air contamination (2) Learn requirements for operating system in low pressure and low temperature environments (3) Design/build system for integration into aircraft and automobiles Secondary Goals/Offshoots are (1) Fly aboard different aircraft (2)Hand-carry unit (3) Drive unit in automobiles.

  14. Monitoring of density in tokamaks: pumping and gas injection

    International Nuclear Information System (INIS)

    Dejarnac, R.

    2002-11-01

    In thermonuclear fusion devices, controlling the Deuterium-Tritium fuel density and exhausting the Helium ashes is a crucial point. This is achieved by fuelling the discharges by different methods (gas puffing and pellet injection are the most commonly used) and by implementing pumping devices at the plasma periphery. These two issues are treated in this work, both from an experimental and a modelling point of view, using the neutral transport code EIRENE as main tool for our studies. As far as pumping is concerned, we have modelled the outboard pump limiter of the Tore Supra tokamak with the EIRENE code to which we coupled a plasma module specially developed to simulate the neutrals and the plasma in a coherent way. This allowed to validate the code against experimental data. As far as plasma fuelling is concerned, we present here an original method: the supersonic pulsed gas injection (SPGI). This intermediate method between conventional gas puff (GP) and pellet injection was designed and tested at Tore Supra. It consists of injecting very dense and short gas puffs at high speed into the plasma. Experimentally, SPGI was found to have a better fuelling efficiency than GP and to lead to a strong plasma cooling. The mechanisms responsible for this improved efficiency are analysed by modelling, using the EIRENE code to determine the ionisation source and a 1 D transport model to reproduce the plasma density response. At last, an extrapolation of the present injector is presented, discussing the possibility to obtain a radial drift of the injected matter as observed in the case of high field side pellet injection. (author)

  15. Environmental Monitoring and the Gas Industry: Program Manager Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Gregory D. Gillispie

    1997-12-01

    This document has been developed for the nontechnical gas industry manager who has the responsibility for the development of waste or potentially contaminated soil and groundwater data or must make decisions based on such data for the management or remediation of these materials. It explores the pse of common analytical chemistry instrumentation and associated techniques for identification of environmentally hazardous materials. Sufficient detail is given to familiarize the nontechnical reader with the principles behind the operation of each technique. The scope and realm of the techniques and their constituent variations are portrayed through a discussion of crucial details and, where appropriate, the depiction of real-life data. It is the author's intention to provide an easily understood handbook for gas industry management. Techniques which determine the presence, composition, and quantification of gas industry wastes are discussed. Greater focus is given to traditional techniques which have been the mainstay of modem analytical benchwork. However, with the continual advancement of instrumental principles and design, several techniques have been included which are likely to receive greater attention in fiture considerations for waste-related detection. Definitions and concepts inherent to a thorough understanding of the principles common to analytical chemistry are discussed. It is also crucial that gas industry managers understand the effects of the various actions which take place before, during, and after the actual sampling step. When a series of sample collection, storage, and transport activities occur, new or inexperienced project managers may overlook or misunderstand the importance of the sequence. Each step has an impact on the final results of the measurement process; errors in judgment or decision making can be costly. Specific techniques and methodologies for the collection, storage, and transport of environmental media samples are not

  16. An in situ method for real-time monitoring of soil gas diffusivity

    Science.gov (United States)

    Laemmel, Thomas; Maier, Martin; Schack-Kirchner, Helmer; Lang, Friederike

    2016-04-01

    Soil aeration is an important factor for the biogeochemistry of soils. Generally, gas exchange between soil and atmosphere is assumed to be governed by molecular diffusion and by this way fluxes can be calculated using by Fick's Law. The soil gas diffusion coefficient DS represents the proportional factor between the gas flux and the gas concentration gradient in the soil and reflects the ability of the soil to "transport passively" gas through the soil. One common way to determine DS is taking core samples in the field and measuring DS in the lab. Unfortunately this method is destructive and laborious and it can only reflect a small fraction of the whole soil. As a consequence, uncertainty about the resulting effective diffusivity on the profile scale, i.e. the real aeration status remains. We developed a method to measure and monitor DS in situ. The set-up consists of a custom made gas sampling device, the continuous injection of an inert tracer gas and inverse gas transport modelling in the soil. The gas sampling device has seven sampling depths (from 0 to -43 cm of depth) and can be easily installed into vertical holes drilled by an auger, which allows for fast installation of the system. Helium (He) as inert tracer gas was injected continuously at the lower end of the device. The resulting steady state distribution of He was used to deduce the DS depth distribution of the soil. For Finite Element Modeling of the gas-sampling-device/soil system the program COMSOL was used. We tested our new method both in the lab and in a field study and compared the results with a reference lab method using soil cores. DS profiles obtained by our in-situ method were consistent with DS profiles determined based on soil core analyses. Soil gas profiles could be measured with a temporal resolution of 30 minutes. During the field study, there was an important rain event and we could monitor the decrease in soil gas diffusivity in the top soil due to water infiltration. The effect

  17. Statistical methods to monitor the West Valley off-gas system

    International Nuclear Information System (INIS)

    Eggett, D.L.

    1990-01-01

    This paper reports on the of-gas system for the ceramic melter operated at the West Valley Demonstration Project at West Valley, NY, monitored during melter operation. A one-at-a-time method of monitoring the parameters of the off-gas system is not statistically sound. Therefore, multivariate statistical methods appropriate for the monitoring of many correlated parameters will be used. Monitoring a large number of parameters increases the probability of a false out-of-control signal. If the parameters being monitored are statistically independent, the control limits can be easily adjusted to obtain the desired probability of a false out-of-control signal. The principal component (PC) scores have desirable statistical properties when the original variables are distributed as multivariate normals. Two statistics derived from the PC scores and used to form multivariate control charts are outlined and their distributional properties reviewed

  18. A simple and rapid method for monitoring dissolved oxygen in water with a submersible microbial fuel cell (SBMFC)

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2012-01-01

    Asubmersiblemicrobial fuel cell (SBMFC) was developed as a biosensor forin situand real time monitoring of dissolvedoxygen (DO) in environmental waters. Domestic wastewater was utilized as sole fuel for powering the sensor. The sensor performance was firstly examined with tap water at varying DO...... the sensing activities. The sensor ability was further explored under different environmental conditions (e.g., pH, temperature, conductivity, alternative electron acceptor), and the results indicated that a calibration would be required before field application. Lastly, the sensor was tested with different...

  19. On-Line Enrichment Monitor for UF{sub 6} Gas Centrifuge Enrichment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Ianakiev, K. D.; Boyer, B.; Favalli, A.; Goda, J. M.; Hill, T.; Keller, C.; Lombardi, M.; Paffett, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Parker, R.; Smith, M. K.; Swinhoe, M. T. [Los Alamos National Laboratory, Los Alamos (United States)

    2012-06-15

    This paper is a continuation of the Advanced Enrichment Monitoring Technology for UF{sub 6} Gas Centrifuge Enrichment Plant (GCEP) work, presented in the 2010 IAEA Safeguards Symposium. Here we will present the system architecture for a planned side-by-side field trial test of passive (186-keV line spectroscopy and pressure-based correction for UF{sub 6} gas density) and active (186-keV line spectroscopy and transmission measurement based correction for UF{sub 6} gas density) enrichment monitoring systems in URENCO's enrichment plant in Capenhurst. Because the pressure and transmission measurements of UF{sub 6} are complementary, additional information on the importance of the presence of light gases and the UF{sub 6} gas temperature can be obtained by cross-correlation between simultaneous measurements of transmission, pressure and 186-keV intensity. We will discuss the calibration issues and performance in the context of accurate, on-line enrichment measurement. It is hoped that a simple and accurate on-line enrichment monitor can be built using the UF{sub 6} gas pressure provided by the Operator, based on online mass spectrometer calibration, assuming a negligible (a small fraction of percent) contribution of wall deposits. Unaccounted-for wall deposits present at the initial calibration will lead to unwanted sensitivity to changes in theUF{sub 6} gas pressure and thus to error in the enrichment results. Because the accumulated deposits in the cascade header pipe have been identified as an issue for Go/No Go measurements with the Cascade Header Enrichment Monitor (CHEM) and Continuous Enrichment Monitor (CEMO), it is important to explore their effect. Therefore we present the expected uncertainty on enrichment measurements obtained by propagating the errors introduced by deposits, gas density, etc. and will discuss the options for a deposit correction during initial calibration of an On-Line Enrichment Monitor (OLEM).

  20. Influence of dissolved product gas on organism retention in biogas tower reactors; Der Einfluss geloester Produktgase auf den Organismenrueckhalt in Biogas-Turmreaktoren

    Energy Technology Data Exchange (ETDEWEB)

    Pietsch, T.; Maerkl, H. [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Arbeitsbereich Bioprozess- und Bioverfahrenstechnik

    1999-07-01

    In biogas tower reactors, considerable oversaturations of CO{sub 2} dissolved in molecular form in the liquid phase can occur, compared to the thermodynamic steady state with the gas phase. In buildings of low height, upflow designs cause biological CO{sub 2} production along the reactor to saturate the liquid phase with carbonic acid, and also cause the pH value increasing from acid degradation to bind CO{sub 2} in the form of hydrogen carbonate HCO{sup -}{sub 3}. Where buildings are very high, the liquid phase becomes degassed through a decrease in CO{sub 2} partial pressure because of decreasing hydrostatic pressure along the length of the reactor. Rising gas bubbles in the liquid phase as well as enclosed gas bubbles in biomass particles slow down their sedimentation considerably and can result in flotation of biomass particles owing to gas expansion from declining hydrostatic pressure. A sedimentation characteristics for biomass under decreasing hydrostatic pressure is given. Conditions critical to biomass retention are energy input into CO{sub 2}-oversaturated liquids as well as dynamically rapid drops in pH value owing to associated CO{sub 2} degassing. (orig.) [German] In Biogas-Turmreaktoren koennen erhebliche Uebersaettigungen von molekular geloestem CO{sub 2} in der Fluessigphase gegenueber dem thermodynamischen Gleichgewichtszustand mit der Gasphase auftreten. Bei geringer Bauhoehe fuehrt bei upflow-Konzepten die biologische CO{sub 2}-Produktion entlang des Reaktors zu einer Aufsaettigung der Fluessigphase mit Kohlensaeure und der durch Saeureabbau ansteigende pH-Wert zu einer Bindung des CO{sub 2} in Form des Hydrogencarbonats HCO{sub 3}{sup -}. Sehr grosse Bauhoehen fuehren zu einer Entgasung der Fluessigphase durch Abnahme des CO{sub 2}-Partialdruckes aufgrund des abnehmenden hydrostatischen Druckes entlang der Reaktorhoehe. Aufsteigende Gasblasen in der Fluessigphase sowie eingeschlossene Gasblasen in Biomassepartikeln mindern deren

  1. Hydrogen sulfide measurement by headspace-gas chromatography-mass spectrometry (HS-GC-MS): application to gaseous samples and gas dissolved in muscle.

    Science.gov (United States)

    Varlet, Vincent; Giuliani, Nicole; Palmiere, Cristian; Maujean, Géraldine; Augsburger, Marc

    2015-01-01

    The aim of our study was to present a new headspace-gas chromatography-mass spectrometry (HS-GC-MS) method applicable to the routine determination of hydrogen sulfide (H(2)S) concentrations in biological and gaseous samples. The primary analytical drawback of the GC/MS methods for H(2)S measurement discussed in the literature was the absence of a specific H(2)S internal standard required to perform quantification. Although a deuterated hydrogen sulfide (D(2)S) standard is currently available, this standard is not often used because this standard is expensive and is only available in the gas phase. As an alternative approach, D(2)S can be generated in situ by reacting deuterated chloride with sodium sulfide; however, this technique can lead to low recovery yield and potential isotopic fractionation. Therefore, N(2)O was chosen for use as an internal standard. This method allows precise measurements of H(2)S concentrations in biological and gaseous samples. Therefore, a full validation using accuracy profile based on the β-expectation tolerance interval is presented. Finally, this method was applied to quantify H(2)S in an actual case of H(2)S fatal intoxication. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Dissolved Gas Analysis Principle-Based Intelligent Approaches to Fault Diagnosis and Decision Making for Large Oil-Immersed Power Transformers: A Survey

    Directory of Open Access Journals (Sweden)

    Lefeng Cheng

    2018-04-01

    Full Text Available Compared with conventional methods of fault diagnosis for power transformers, which have defects such as imperfect encoding and too absolute encoding boundaries, this paper systematically discusses various intelligent approaches applied in fault diagnosis and decision making for large oil-immersed power transformers based on dissolved gas analysis (DGA, including expert system (EPS, artificial neural network (ANN, fuzzy theory, rough sets theory (RST, grey system theory (GST, swarm intelligence (SI algorithms, data mining technology, machine learning (ML, and other intelligent diagnosis tools, and summarizes existing problems and solutions. From this survey, it is found that a single intelligent approach for fault diagnosis can only reflect operation status of the transformer in one particular aspect, causing various degrees of shortcomings that cannot be resolved effectively. Combined with the current research status in this field, the problems that must be addressed in DGA-based transformer fault diagnosis are identified, and the prospects for future development trends and research directions are outlined. This contribution presents a detailed and systematic survey on various intelligent approaches to faults diagnosing and decisions making of the power transformer, in which their merits and demerits are thoroughly investigated, as well as their improvement schemes and future development trends are proposed. Moreover, this paper concludes that a variety of intelligent algorithms should be combined for mutual complementation to form a hybrid fault diagnosis network, such that avoiding these algorithms falling into a local optimum. Moreover, it is necessary to improve the detection instruments so as to acquire reasonable characteristic gas data samples. The research summary, empirical generalization and analysis of predicament in this paper provide some thoughts and suggestions for the research of complex power grid in the new environment, as

  3. The Potential Applications of Real-Time Monitoring of Water Quality in a Large Shallow Lake (Lake Taihu, China Using a Chromophoric Dissolved Organic Matter Fluorescence Sensor

    Directory of Open Access Journals (Sweden)

    Cheng Niu

    2014-06-01

    Full Text Available This study presents results from field surveys performed over various seasons in a large, eutrophic, shallow lake (Lake Taihu, China using an in situ chromophoric dissolved organic matter (CDOM fluorescence sensor as a surrogate for other water quality parameters. These measurements identified highly significant empirical relationships between CDOM concentration measured using the in situ fluorescence sensor and CDOM absorption, fluorescence, dissolved organic carbon (DOC, chemical oxygen demand (COD and total phosphorus (TP concentrations. CDOM concentration expressed in quinine sulfate equivalent units, was highly correlated with the CDOM absorption coefficient (r2 = 0.80, p < 0.001, fluorescence intensities (Ex./Em. 370/460 nm (r2 = 0.91, p < 0.001, the fluorescence index (r2 = 0.88, p < 0.001 and the humification index (r2 = 0.78, p < 0.001, suggesting that CDOM concentration measured using the in situ fluorescence sensor could act as a substitute for the CDOM absorption coefficient and fluorescence measured in the laboratory. Similarly, CDOM concentration was highly correlated with DOC concentration (r2 = 0.68, p < 0.001, indicating that in situ CDOM fluorescence sensor measurements could be a proxy for DOC concentration. In addition, significant positive correlations were found between laboratory CDOM absorption coefficients and COD (r2 = 0.83, p < 0.001, TP (r2 = 0.82, p < 0.001 concentrations, suggesting a potential further application for the real-time monitoring of water quality using an in situ CDOM fluorescence sensor.

  4. French wholesale electricity and gas markets in 2007. Monitoring report

    International Nuclear Information System (INIS)

    2008-12-01

    Settled on 24 March 2000, the French Energy Regulatory Commission (CRE) is an independent authority. CRE supports an efficient functioning of the electricity and natural gas markets, to the advantage of final consumers. CRE ensures the absence of any discrimination, cross subsidy or obstacle to competition. CRE has examined the functioning of the wholesale markets for electricity and gas for the year 2007. The report discloses the results of a first set of analyses, as well as the next actions to be conducted in order to explain some observed behaviour. On the basis of analyses led on the electricity market, CRE observes that nuclear generation was marginal during 15% of the hours in 2007. Hydraulic generation was marginal during 25% of the hours, coal generation during 25% to 30% of the hours and oil generation during less than 2% of the hours in 2007. Finally, prices on the border markets were of high importance on the French prices which they determined during 20% to 25% of the hours of the year. On an efficient market, the price is driven by the marginal power plant among all those which contribute to satisfy the demand. Therefore the wholesale price formation is conditioned by the frequency of marginality of each generation sector and by the associated valuation of production. On the day-ahead market, when nuclear or hydraulic generation was marginal, the day-ahead price reflected the associated valuation which was decided by EDF. The level of this valuation was generally higher than the marginal generation cost of these plants. As a matter of fact, a producer, even market dominant, may legitimately seek to optimise its income, provided that there is no abuse of a dominant position or any price manipulation. Consequently, at this stage, the relevance of the valuation method for nuclear and hydraulic generation on the wholesale market is still to be checked. CRE has also demonstrated that generation transparency, even if it gradually increased, still needs to

  5. Systematic study of RPC performances in polluted or varying gas mixtures compositions: an online monitor system for the RPC gas mixture at LHC

    CERN Document Server

    Capeans, M; Mandelli, B

    2012-01-01

    The importance of the correct gas mixture for the Resistive Plate Chamber (RPC) detector systems is fundamental for their correct and safe operation. A small change in the percentages of the gas mixture components can alter the RPC performance and this will rebound on the data quality in the ALICE, ATLAS and CMS experiments at CERN. A constant monitoring of the gas mixture injected in the RPCs would avoid such kind of problems. A systematic study has been performed to understand RPC performances with several gas mixture compositions and in the presence of common gas impurities. The systematic analysis of several RPC performance parameters in different gas mixtures allows the rapid identification of any variation in the RPC gas mixture. A set-up for the online monitoring of the RPC gas mixture in the LHC gas systems is also proposed.

  6. Comparative study of gas-analyzing systems designed for continuous monitoring of TPP emissions

    Science.gov (United States)

    Kondrat'eva, O. E.; Roslyakov, P. V.

    2017-06-01

    Determining the composition of combustion products is important in terms of both control of emissions into the atmosphere from thermal power plants and optimization of fuel combustion processes in electric power plants. For this purpose, the concentration of oxygen, carbon monoxide, nitrogen, and sulfur oxides in flue gases is monitored; in case of solid fuel combustion, fly ash concentration is monitored as well. According to the new nature conservation law in Russia, all large TPPs shall be equipped with continuous emission monitoring and measurement systems (CEMMS) into the atmosphere. In order to ensure the continuous monitoring of pollutant emissions, direct round-the-clock measurements are conducted with the use of either domestically produced or imported gas analyzers and analysis systems, the operation of which is based on various physicochemical methods and which can be generally used when introducing CEMMS. Depending on the type and purposes of measurement, various kinds of instruments having different features may be used. This article represents a comparative study of gas-analysis systems for measuring the content of polluting substances in exhaust gases based on various physical and physicochemical analysis methods. It lists basic characteristics of the methods commonly applied in the area of gas analysis. It is proven that, considering the necessity of the long-term, continuous operation of gas analyzers for monitoring and measurement of pollutant emissions into the atmosphere, as well as the requirements for reliability and independence from aggressive components and temperature of the gas flow, it is preferable to use optical gas analyzers for the aforementioned purposes. In order to reduce the costs of equipment comprising a CEMMS at a TPP and optimize the combustion processes, electrochemical and thermomagnetic gas analyzers may also be used.

  7. High concentration tritium gas measurement with small volume ionization chambers for fusion fuel gas monitors

    International Nuclear Information System (INIS)

    Uda, Tatsuhiko; Okuno, Kenji; Matsuda, Yuji; Naruse, Yuji

    1991-01-01

    To apply ionization chambers to fusion fuel gas processing systems, high concentration tritium gas was experimentally measured with small volume 0.16 and 21.6 cm 3 ionization chambers. From plateau curves, the optimum electric field strength was obtained as 100∼200 V/cm. Detection efficiency was confirmed as dependent on the ionization ability of the filled gas, and moreover on its stopping power, because when the range of the β-rays was shortened, the probability of energy loss by collisions with the electrode and chamber wall increased. Loss of ions by recombination was prevented by using a small volume ionization chamber. For example the 0.16 cm 3 ionization chamber gave measurement with linearity to above 40% tritium gas. After the tritium gas measurements, the concentration levels inside the chamber were estimated from their memory currents. Although more than 1/4,000 of the maximum, current was observed as a memory effect, the smaller ionization chamber gave a smaller memory effect. (author)

  8. Tracking changes in composition and amount of dissolved organic matter throughout drinking water treatment plants by comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry.

    Science.gov (United States)

    Li, Chunmei; Wang, Donghong; Xu, Xiong; Xu, Meijia; Wang, Zijian; Xiao, Ruiyang

    2017-12-31

    Dissolved organic matter (DOM) can affect the performance of water treatment processes and produce undesirable disinfection by-products during disinfection. Several studies have been undertaken on the structural characterization of DOM, but its fate during drinking water treatment processes is still not fully understood. In this work, the nontargeted screening method of comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry (GC×GC-qMS) was used to reveal the detailed changes of different chemical classes of compounds in DOM during conventional and advanced drinking water treatment processes at three drinking water treatment plants in China. The results showed that when the dissolved organic carbon removal was low, shifts in the DOM composition could not be detected with the specific ultraviolet absorbance at 254nm, but the changes were clear in the three-dimensional fluorescence excitation-emission matrix or GC×GC-qMS analyses. Coagulation-sedimentation processes selectively removed 37-59% of the nitrogenous compounds, alcohols and aromatic hydrocarbons but increased the concentrations of halogen-containing compounds by 17-26% because of the contact time with chlorine in this step. Filtration was less efficient at removing DOM but preferentially removed 21-60% of the acids. However, other organic matter would be released from the filter (e.g., nitrogenous compounds, acids, and aromatic hydrocarbons). Biological activated carbon (BAC) treatment removed most of the compounds produced from ozonation, particularly ketones, alcohols, halogen-containing compounds and acids. However, it should be noted that certain highly polar or high molecular weight compounds not identified in this study might be released from the BAC bed. After the whole treatment processes, the concentrations of nitrogenous compounds, alcohols, alkenes, aromatic hydrocarbons and ketones were decreased more by the advanced treatment processes than by the conventional treatment

  9. Review of Small Commercial Sensors for Indicative Monitoring of Ambient Gas

    OpenAIRE

    ALEIXANDRE Manuel; GERBOLES Michel

    2012-01-01

    The traditional ambient gases monitor stations are expensive, big and of complex operation. So they are not suitable for a network of sensors that cover large areas. To cover large areas these traditional systems algorithms usually interpolates the measurements to calculate the gas concentrations in points far away of the physical sensors. Small commercial sensors represent a big opportunity for making sensor networks that monitor the ambient gases within large areas w...

  10. RECOMMENDATIONS ON THE MONITORING SYSTEM OF UNDERGROUND GAS STORAGE (in Russian

    Directory of Open Access Journals (Sweden)

    Victor NORDIN

    2014-07-01

    Full Text Available The article in accordance with the "process approach" ISO 9000 is substantiated the necessity of creating underground gas storage system monitoring and control, including objects, parameters, methods, frequency and corrective action, on the basis of which made structural formula monitoring cycle. Qualimetrical approach allows to define complex criteria of an estimation of efficiency of operation, which will help to make timely and effective management decisions, including from the perspective of environmental protection.

  11. Hierarchical Leak Detection and Localization Method in Natural Gas Pipeline Monitoring Sensor Networks

    OpenAIRE

    Ning Yu; Renjian Feng; Jiangwen Wan; Yinfeng Wu; Yang Yu

    2011-01-01

    In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initia...

  12. Gas monitoring in human sinuses using tunable diode laser spectroscopy.

    Science.gov (United States)

    Persson, Linda; Andersson, Mats; Cassel-Engquist, Märta; Svanberg, Katarina; Svanberg, Sune

    2007-01-01

    We demonstrate a novel nonintrusive technique based on tunable diode laser absorption spectroscopy to investigate human sinuses in vivo. The technique relies on the fact that free gases have spectral imprints that are about 10.000 times sharper than spectral structures of the surrounding tissue. Two gases are detected; molecular oxygen at 760 nm and water vapor at 935 nm. Light is launched fiber optically into the tissue in close proximity to the particular maxillary sinus under study. When investigating the frontal sinuses, the fiber is positioned onto the caudal part of the frontal bone. Multiply scattered light in both cases is detected externally by a handheld probe. Molecular oxygen is detected in the maxillary sinuses on 11 volunteers, of which one had constantly recurring sinus problems. Significant oxygen absorption imprint differences can be observed between different volunteers and also left-right asymmetries. Water vapor can also be detected, and by normalizing the oxygen signal on the water vapor signal, the sinus oxygen concentration can be assessed. Gas exchange between the sinuses and the nasal cavity is also successfully demonstrated by flushing nitrogen through the nostril. Advantages over current ventilation assessment methods using ionizing radiation are pointed out.

  13. Isotope Ratio Monitoring Gas Chromatography Mass Spectrometry (IRM-GCMS)

    International Nuclear Information System (INIS)

    Freeman, K.H.; Ricci, S.A.; Studley, A.; Hayes, J.M.

    1989-01-01

    On Earth, the C-13 content of organic compounds is depleted by roughly 13 to 23 permil from atmospheric carbon dioxide. This difference is largely due to isotope effects associated with the fixation of inorganic carbon by photosynthetic organisms. If life once existed on Mars, then it is reasonable to expect to observe a similar fractionation. Although the strongly oxidizing conditions on the surface of Mars make preservation of ancient organic material unlikely, carbon-isotope evidence for the existence of life on Mars may still be preserved. Carbon depleted in C-13 could be preserved either in organic compounds within buried sediments, or in carbonate minerals produced by the oxidation of organic material. A technique is introduced for rapid and precise measurement of the C-13 contents of individual organic compounds. A gas chromatograph is coupled to an isotope-ratio mass spectrometer through a combustion interface, enabling on-line isotopic analysis of isolated compounds. The isotope ratios are determined by integration of ion currents over the course of each chromatographic peak. Software incorporates automatic peak determination, corrections for background, and deconvolution of overlapped peaks. Overall performance of the instrument was evaluated by the analysis of a mixture of high purity n-alkanes of know isotopic composition. Isotopic values measured via IRM-GCMS averaged withing 0.55 permil of their conventionally measured values

  14. High-Resolution Gas Metering and Nonintrusive Appliance Load Monitoring System

    Science.gov (United States)

    Tewolde, Mahder

    This thesis deals with design and implementation of a high-resolution metering system for residential natural gas meters. Detailed experimental measurements are performed on the meter to characterize and understand its measurement properties. Results from these experiments are used to develop a simple, fast and accurate technique to non-intrusively monitor the gas consumption of individual appliances in homes by resolving small amounts of gas usage. The technique is applied on an existing meter retrofitted with a module that includes a high-resolution encoder to collect gas flow data and a microprocessor to analyze and identify appliance load profiles. This approach provides a number of appealing features including low cost, easy installation and integration with automated meter reading (AMR) systems. The application of this method to residential gas meters currently deployed is also given. This is done by performing a load simulation on realistic gas loads with the aim of identifying the necessary parameters that minimize the cost and complexity of the mechanical encoder module. The primary benefits of the system are efficiency analysis, appliance health monitoring and real-time customer feedback of gas usage. Additional benefits of include the ability to detect very small leaks and theft. This system has the potential for wide scale market adoption.

  15. Independent determination of the accuracy of the OSTR stack gas monitor and its operational application

    International Nuclear Information System (INIS)

    Pickett, B.D.; Johnson, A.G.

    1982-01-01

    This study was undertaken to determine the accuracy of the stack gas monitor, using techniques which were independent of the monitoring system itself. Samples of argon-41 to be used as the standards in this study were carefully produced in the thermal column of the OSTR and counted on a Ge(Li) detector which was connected to a multichannel analyzer (MCA). As the argon-41 standard in the gas sample flask decayed, the concentration of the argon-41 was compared to the output of the Ge(Li)/MCA system. This established a calibration curve for the counting system, whereby a sample with an unknown concentration of argon-41 could be counted and the subsequent count rate from the sample converted to a concentration expressed in mCi per milliliter. Gas samples were extracted from various points in the reactor exhaust system and the concentrations of argon-41 were determined by counting on the Ge(Li)/MCA system. Each sample concentration was then compared to the argon-41 concentration indicated by the stack gas monitor. The initial results indicated that, although possibly intermittent, the argon-41 concentrations displayed by the stack gas monitor were often approximately 50% of those predicted by analysis of individual samples from the exhaust system. Several possible sources for the discrepancy were checked, including the method of SGM calibration, uneven mixing of exhaust air and argon-41 in the reactor building exhaust stream, and dilution of the gas concentration in the SGM system by air leakage into the system. After considerable effort, the latter cause was found to be the culprit, due to an aging gasket around the stack monitor's moving particulate-filter-paper housing

  16. Designing optimal greenhouse gas monitoring networks for Australia

    Science.gov (United States)

    Ziehn, T.; Law, R. M.; Rayner, P. J.; Roff, G.

    2016-01-01

    Atmospheric transport inversion is commonly used to infer greenhouse gas (GHG) flux estimates from concentration measurements. The optimal location of ground-based observing stations that supply these measurements can be determined by network design. Here, we use a Lagrangian particle dispersion model (LPDM) in reverse mode together with a Bayesian inverse modelling framework to derive optimal GHG observing networks for Australia. This extends the network design for carbon dioxide (CO2) performed by Ziehn et al. (2014) to also minimise the uncertainty on the flux estimates for methane (CH4) and nitrous oxide (N2O), both individually and in a combined network using multiple objectives. Optimal networks are generated by adding up to five new stations to the base network, which is defined as two existing stations, Cape Grim and Gunn Point, in southern and northern Australia respectively. The individual networks for CO2, CH4 and N2O and the combined observing network show large similarities because the flux uncertainties for each GHG are dominated by regions of biologically productive land. There is little penalty, in terms of flux uncertainty reduction, for the combined network compared to individually designed networks. The location of the stations in the combined network is sensitive to variations in the assumed data uncertainty across locations. A simple assessment of economic costs has been included in our network design approach, considering both establishment and maintenance costs. Our results suggest that, while site logistics change the optimal network, there is only a small impact on the flux uncertainty reductions achieved with increasing network size.

  17. Direct monitoring of wind-induced pressure-pumping on gas transport in soil

    Science.gov (United States)

    Laemmel, Thomas; Mohr, Manuel; Schindler, Dirk; Schack-Kirchner, Helmer; Maier, Martin

    2017-04-01

    Gas exchange between soil and atmosphere is important for the biogeochemistry of soils and is commonly assumed to be governed by molecular diffusion. Yet a few previous field studies identified other gas transport processes such as wind-induced pressure-pumping to enhance soil-atmosphere fluxes significantly. However, since these wind-induced non-diffusive gas transport processes in soil often occur intermittently, the quantification of their contribution to soil gas emissions is challenging. To quantify the effects of wind-induced pressure-pumping on soil gas transport, we developed a method for in situ monitoring of soil gas transport. The method includes the use of Helium (He) as a tracer gas which was continuously injected into the soil. The resulting He steady-state concentration profile was monitored. Gas transport parameters of the soil were inversely modelled. We used our method during a field campaign in a well-aerated forest soil over three months. During periods of low wind speed, soil gas transport was modelled assuming diffusion as transport process. During periods of high wind speed, the previously steady diffusive He concentration profile showed temporary concentration decreases in the topsoil, indicating an increase of the effective gas transport rate in the topsoil up to 30%. The enhancement of effective topsoil soil gas diffusivity resulted from wind-induced air pressure fluctuations which are referred to as pressure-pumping. These air pressure fluctuations had frequencies between 0.1 and 0.01 Hz and amplitudes up to 10 Pa and occurred at above-canopy wind speeds greater than 5 m s-1. We could show the importance of the enhancement of the gas transport rate in relation with the wind intensity and corresponding air pressure fluctuations characteristics. We directly detected and quantified the pressure-pumping effect on gas transport in soil in a field study for the first time, and could thus validate and underpin the importance of this non

  18. Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks

    Directory of Open Access Journals (Sweden)

    Guangwen Fan

    2015-09-01

    Full Text Available Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, automatic data acquisition and management, local and remote access make the developed system a good alternative for temperature monitoring of LPG storage tanks in practical applications.

  19. Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks.

    Science.gov (United States)

    Fan, Guangwen; Shen, Yu; Hao, Xiaowei; Yuan, Zongming; Zhou, Zhi

    2015-09-18

    Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG) storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, automatic data acquisition and management, local and remote access make the developed system a good alternative for temperature monitoring of LPG storage tanks in practical applications.

  20. Comparison of photoacoustic radiometry to gas chromatography/mass spectrometry methods for monitoring chlorinated hydrocarbons

    International Nuclear Information System (INIS)

    Sollid, J.E.; Trujillo, V.L.; Limback, S.P.; Woloshun, K.A.

    1996-01-01

    A comparison of two methods of gas chromatography mass spectrometry (GCMS) and a nondispersive infrared technique, photoacoustic radiometry (PAR), is presented in the context of field monitoring a disposal site. First is presented an historical account describing the site and early monitoring to provide an overview. The intent and nature of the monitoring program changed when it was proposed to expand the Radiological Waste Site close to the Hazardous Waste Site. Both the sampling methods and analysis techniques were refined in the course of this exercise

  1. Gas-phase UF6 enrichment monitor for enrichment plant safeguards

    International Nuclear Information System (INIS)

    Strittmatter, R.B.; Tape, J.W.

    1980-03-01

    An in-line enrichment monitor is being developed to provide real-time enrichment data for the gas-phase UF 6 feed stream of an enrichment plant. The nondestructive gamma-ray assay method can be used to determine the enrichment of natural UF 6 with a relative precision of better than 1% for a wide range of pressures

  2. Monitoring air pollutants due to gas flaring using rain water | Rim ...

    African Journals Online (AJOL)

    The mean levels of conductivity, TDS, and SO42- were within statutory safe limits, while that of pH, CO32- and NO3- were above the safe limits specified by the Federal Ministry of Environment guidelines and standards for drinking water quality. Keywords: rainwater, gas flare, pollutants, monitoring, water quality

  3. Design layout for gas monitoring system II, GMS-2, computer system

    International Nuclear Information System (INIS)

    Vo, V.; Philipp, B.L.; Manke, M.P.

    1995-01-01

    This document provides a general overview of the computer systems software that perform the data acquisition and control for the 241-SY-101 Gas Monitoring System II (GMS-2). It outlines the system layout, and contains descriptions of components and the functions they perform. The GMS-2 system was designed and implemented by Los Alamos National Laboratory and supplied to Westinghouse Hanford Company

  4. Optimization of the monitoring of landfill gas and leachate in closed methanogenic landfills.

    Science.gov (United States)

    Jovanov, Dejan; Vujić, Bogdana; Vujić, Goran

    2018-06-15

    Monitoring of the gas and leachate parameters in a closed landfill is a long-term activity defined by national legislative worldwide. Serbian Waste Disposal Law defines the monitoring of a landfill at least 30 years after its closing, but the definition of the monitoring extent (number and type of parameters) is incomplete. In order to define and clear all the uncertainties, this research focuses on process of monitoring optimization, using the closed landfill in Zrenjanin, Serbia, as the experimental model. The aim of optimization was to find representative parameters which would define the physical, chemical and biological processes in the closed methanogenic landfill and to make this process less expensive. Research included development of the five monitoring models with different number of gas and leachate parameters and each model has been processed in open source software GeoGebra which is often used for solving optimization problems. The results of optimization process identified the most favorable monitoring model which fulfills all the defined criteria not only from the point of view of mathematical analyses, but also from the point of view of environment protection. The final outcome of this research - the minimal required parameters which should be included in the landfill monitoring are precisely defined. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. A technical evaluation of the EDA radon gas continuous monitoring system

    International Nuclear Information System (INIS)

    Bigu, J.

    1979-04-01

    Extensive laboratory and underground tests were conducted with a radon gas continuous monitoring system built by EDA Instruments Inc. The system consists of several remote radon gas sensors linked via signal cables to a central control unit that fully controls the operation of the radon monitors. The system enables four operations to be performed: sampling, background, flush and bypass. The sequence and duration of these functions is programmable. Up to 20 functions in any desired pattern each lasting from 1 min to 23 hr 59 min can be programmed. Several programs were used during the experiments in order to obtain radon and thoron gas levels. The performance of the EDA system was quite satisfactory. It is suggested that ruggedization as well as some other modifications be introdouced into the system to: a) better withstand the harsh underground environment; and b) improve its performance

  6. The use of a low-cost gas-liquid flow meter to monitor severe slugging

    DEFF Research Database (Denmark)

    Andreussi, Paolo; Bonizzi, Marco; Ciandri, Paolo

    2017-01-01

    A very simple, low-cost gas-liquid flow meter that only employs conventional field instrumentation has been used to monitor severe slugging occurring at the exit of a vertical pipe. This meter was originally developed for conventional oil field applications [1] and is based on the readings...... method to monitor severe slugging by means of low cost instrumentation, in particular, by replacing a cumbersome instrument such as a gamma-densitometer with a differential pressure transmitter. In field operation, the multiphase orifice used in these experiments can be replaced by a calibrated control...... of a multiphase orifice and the pressure drops of the gas-liquid mixture flowing in a vertical section of the pipe. Liquid and gas flow rates have been determined by means of semi-empirical equations developed for the specific set of flow parameters (geometry, flow rates, physical properties) adopted in a series...

  7. Artificial neural networks for monitoring the gas turbine; Artificiella neuronnaet foer gasturbinoevervakning

    Energy Technology Data Exchange (ETDEWEB)

    Fast, Magnus; Thern, Marcus [Inst. foer Energivetenskaper, Lunds Univ. (Sweden)

    2011-10-15

    Through available historical operational data from gas turbines, fast, accurate, easy to use and reliable models can be developed. These models can be used for monitoring of gas turbines and assist in the transition from today's time-based maintenance to condition based maintenance. For the end user this means that, because only operational data is needed, they can easily develop their own tools independent of the manufacturer. Traditionally these types of models are constructed with physical relations for e.g., mass, energy and momentum. To develop a model with physical relations is often laborious and requires classified information which the end user does not have access to. Research has shown that by producing models using operational data a very high model precision can be achieved. When implementing these models in a power plant computer system the gas turbine's performance can be monitored in real time. This can facilitate fault detection at an early stage, and if necessary, stop the gas turbine before major damage occurs. For the power plant owner, this means that the gas turbine reliability is increased since the need for maintenance is minimized and the downtime is reduced. It also means that a measure of the gas turbine's overall status is continuously available, with respect to e.g. degradation, which helps in the planning of service intervals. The tool used is called artificial neural networks (ANN), a collective name for a number of algorithms for information processing that attempts to mimic the nerve cell function. Just like real networks of neurons in a brain, these artificial neural networks have the ability to learn. In this case, neural networks are trained to mimic the behavior of gas turbines by introducing them to data from real gas turbines. After a neural network is trained it represents a very accurate model of the gas turbine that it is trained to emulate.

  8. Using Wireless Sensor Networks to Achieve Intelligent Monitoring for High-Temperature Gas-Cooled Reactor

    Directory of Open Access Journals (Sweden)

    Jianghai Li

    2017-01-01

    Full Text Available High-temperature gas-cooled reactors (HTGR can incorporate wireless sensor network (WSN technology to improve safety and economic competitiveness. WSN has great potential in monitoring the equipment and processes within nuclear power plants (NPPs. This technology not only reduces the cost of regular monitoring but also enables intelligent monitoring. In intelligent monitoring, large sets of heterogeneous data collected by the WSN can be used to optimize the operation and maintenance of the HTGR. In this paper, WSN-based intelligent monitoring schemes that are specific for applications of HTGR are proposed. Three major concerns regarding wireless technology in HTGR are addressed: wireless devices interference, cybersecurity of wireless networks, and wireless standards selected for wireless platform. To process nonlinear and non-Gaussian data obtained by WSN for fault diagnosis, novel algorithms combining Kernel Entropy Component Analysis (KECA and support vector machine (SVM are developed.

  9. Determination of perfluorobutane in rat blood by automatic headspace capillary gas chromatography and selected ion monitoring mass spectrometry.

    Science.gov (United States)

    Hvattum, E; Normann, P T; Oulie, I; Uran, S; Ringstad, O; Skotland, T

    2001-01-01

    A new contrast agent (Sonazoid; NC100100) for ultrasound imaging has been developed. It is an aqueous suspension of lipid stabilised perfluorobutane (PFB) gas microbubbles. An automatic headspace capillary gas-chromatographic mass spectrometric method using electron impact ionisation was developed for analysis of Sonazoid PFB in rat blood. The calibration standards were gaseous PFB dissolved in ethanol in the range of 0.5-5000 ng PFB. Fluorotrichloromethane (CFC 11) was used as an internal standard of the method and the MS detector was set to single ion monitoring of the base fragment ions of PFB (m/z 69 and 119) and CFC 11 (m/z 101). The calibration graph, made by plotting the peak area ratios of PFB (m/z 69) to CFC 11(m/z 101) against the amount of PFB, was fitted to a second-order polynomial equation with weighting 1/y2 and found to be reproducible. The limit of quantification of the method was set to 0.4 ng PFB. The between-day variation of the method was below 9.2% relative standard deviation (RSD) and the within-day variation of the method was below 7.6% RSD. The accuracy of the method, as compared to Coulter counter, was estimated by determination of PFB in samples where Sonazoid was added to saline and found to range from 91.5% to 105.2%. PFB, added as Sonazoid, was found to be stable for at least 7 months in rat blood samples when stored at -20 degrees C.

  10. Control and monitoring of landfill gas underground migration at the City of Montreal sanitary landfill site

    International Nuclear Information System (INIS)

    Heroux, M.; Turcotte, L.

    1997-01-01

    The proposed paper covers the various aspects of control and monitoring of potential landfill gas (LFG) migration through soil voids or rock fractures at the City of Montreal sanitary landfill site. It depicts the social, geographical and geological context and presents a brief history of the landfill site. It describes the LFG collecting system and LFG migration monitoring equipment and programs. Finally it presents monitoring data taken over last few years. The landfill site is located in a well populated urban area. Since 1968, about 33 million metric tons of domestic and commercial waste have been buried in a former limestone quarry. Because of houses and buildings in the vicinity, 100 m in some locations, LFG underground migration is a major risk. LFG could indeed infiltrate buildings and reach explosive concentrations. So it must be controlled. The City of Montreal acquired the site in 1988 and has progressively built a LFG collecting system, composed of more than 288 vertical wells, to pump out of the landfill 280 million m 3 of gas annually. To verify the efficiency of this system to minimize LFG underground migration, monitoring equipment and programs have also been designed and put into operation. The monitoring network, located all around the landfill area, is composed of 21 well nests automated to monitor presence of gas in the ground in real time. In addition, 55 individual wells, where manual measurements are made, are also available. To complete the monitoring program, some measurements are also taken in buildings, houses and underground utilities in the neighborhood of the site. Monitoring data show that LFG underground migration is well controlled. They also indicate significant decrease of migration over the years corresponding to improvements to the LFG collecting system

  11. Deployment Algorithms of Wireless Sensor Networks for Near-surface Underground Oil and Gas Pipeline Monitoring

    Directory of Open Access Journals (Sweden)

    Hua-Ping YU

    2014-07-01

    Full Text Available Oil and gas pipelines are the infrastructure of national economic development. Deployment problem of wireless underground sensor networks (WUSN for oil and gas pipeline systems is a fundamental problem. This paper firstly analyzed the wireless channel characteristics and energy consumption model in near-surface underground soil, and then studied the spatial structure of oil and gas pipelines and introduced the three-layer system structure of WUSN for oil and gas pipelines monitoring. Secondly, the optimal deployment strategy in XY plane and XZ plane which were projected from three-dimensional oil and gas pipeline structure was analyzed. Thirdly, the technical framework of using kinetic energy of the fluid in pipelines to recharge sensor nodes and partition strategy for energy consumption balance based on the wireless communication technology of magnetic induction waveguide were proposed, which can effectively improve the energy performance and connectivity of the network, and provide theoretical guidance and practical basis for the monitoring of long oil and gas pipeline network, the city tap water pipe network and sewage pipe network.

  12. Membrane-Coated Electrochemical Sensor for Corrosion Monitoring in Natural Gas Pipelines

    Directory of Open Access Journals (Sweden)

    J. Beck

    2017-07-01

    Full Text Available Electrochemical sensors can be used for a wide range of online in- situ process monitoring applications. However, the lack of a consistent electrolyte layer has previously limited electrochemical monitoring in gas and supercritical fluid streams. A solid state sensor is being designed that uses an ion conducting membrane to perform conductivity and corrosion measurements in natural gas pipelines up to 1000 psi. Initial results show that membrane conductivity measurements can be correlated directly to water content down to dew points of 1°C with good linearity. Corrosion monitoring can also be performed using methods such as linear polarization resistance and electrochemical impedance spectroscopy (EIS, though care must be taken in the electrode design to minimize deviation between sensors.

  13. Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth A. Yackly

    2005-12-01

    The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, was re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for coal/IGCC powerplants. The new program was re-titled ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants''. This final report summarizes the work accomplished from March 1, 2003 to March 31, 2004 on the four original tasks, and the work accomplished from April 1, 2004 to July 30, 2005 on the two re-directed tasks. The program Tasks are summarized below: Task 1--IGCC Environmental Impact on high Temperature Materials: The first task was refocused to address IGCC environmental impacts on high temperature materials used in gas turbines. This task screened material performance and quantified the effects of high temperature erosion and corrosion of hot gas path materials in coal/IGCC applications. The materials of interest included those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: The second task was reduced in scope to demonstrate new technologies to determine the inservice health of advanced technology coal/IGCC powerplants. The task focused on two critical sensing needs for advanced coal/IGCC gas turbines: (1) Fuel Quality Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and detection of fuel impurities that could lead to rapid component degradation. (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware. Task 3--Advanced Methods for Combustion Monitoring and Control: The third task was originally to develop and validate advanced monitoring and control methods for coal/IGCC gas

  14. Velocimetry using scintillation of a laser beam for a laser-based gas-flux monitor

    Science.gov (United States)

    Kagawa, Naoki; Wada, Osami; Koga, Ryuji

    1999-05-01

    This paper describes a velocimetry system using scintillation of a laser-beam with spatial filters based on sensor arrays for a laser- based gas flux monitor. In the eddy correlation method, gas flux is obtained by mutual relation between the gas density and the flow velocity. The velocimetry system is developed to support the flow velocity monitor portion of the laser-based gas flux monitor with a long span for measurement. In order to sense not only the flow velocity but also the flow direction, two photo diode arrays are arranged with difference of a quarter period of the weighting function between them; the two output signals from the sensor arrays have phase difference of either (pi) /2 or -(pi) /2 depending on the sense of flow direction. In order to obtain the flow velocity and the flow direction instantly, an electronic apparatus built by the authors extracts frequency and phase from crude outputs of the pair of sensors. A feasibility of the velocimetry was confirmed indoors by measurement of the flow- velocity vector of the convection. Measured flow-velocity vector of the upward flow agreed comparatively with results of an ultrasonic anemometer.

  15. Aircraft Gas Turbine Engine Health Monitoring System by Real Flight Data

    Directory of Open Access Journals (Sweden)

    Mustagime Tülin Yildirim

    2018-01-01

    Full Text Available Modern condition monitoring-based methods are used to reduce maintenance costs, increase aircraft safety, and reduce fuel consumption. In the literature, parameters such as engine fan speeds, vibration, oil pressure, oil temperature, exhaust gas temperature (EGT, and fuel flow are used to determine performance deterioration in gas turbine engines. In this study, a new model was developed to get information about the gas turbine engine’s condition. For this model, multiple regression analysis was carried out to determine the effect of the flight parameters on the EGT parameter and the artificial neural network (ANN method was used in the identification of EGT parameter. At the end of the study, a network that predicts the EGT parameter with the smallest margin of error has been developed. An interface for instant monitoring of the status of the aircraft engine has been designed in MATLAB Simulink. Any performance degradation that may occur in the aircraft’s gas turbine engine can be easily detected graphically or by the engine performance deterioration value. Also, it has been indicated that it could be a new indicator that informs the pilots in the event of a fault in the sensor of the EGT parameter that they monitor while flying.

  16. Seismo-Geochemical Variations in SW Taiwan: Multi-Parameter Automatic Gas Monitoring Results

    Science.gov (United States)

    Yang, T. F.; Fu, C.-C.; Walia, V.; Chen, C.-H.; Chyi, L. L.; Liu, T.-K.; Song, S.-R.; Lee, M.; Lin, C.-W.; Lin, C.-C.

    2006-04-01

    Gas variations of many mud volcanoes and hot springs distributed along the tectonic sutures in southwestern Taiwan are considered to be sensitive to the earthquake activity. Therefore, a multi-parameter automatic gas station was built on the bank of one of the largest mud-pools at an active fault zone of southwestern Taiwan, for continuous monitoring of CO2, CH4, N2 and H2O, the major constituents of its bubbling gases. During the year round monitoring from October 2001 to October 2002, the gas composition, especially, CH4 and CO2, of the mud pool showed significant variations. Taking the CO2/CH4 ratio as the main indicator, anomalous variations can be recognized from a few days to a few weeks before earthquakes and correlated well with those with a local magnitude >4.0 and local intensities >2. It is concluded that the gas composition in the area is sensitive to the local crustal stress/strain and is worthy to conduct real-time monitoring for the seismo-geochemical precursors.

  17. Real-time drilling mud gas monitoring for qualitative evaluation of hydrocarbon gas composition during deep sea drilling in the Nankai Trough Kumano Basin.

    Science.gov (United States)

    Hammerschmidt, Sebastian B; Wiersberg, Thomas; Heuer, Verena B; Wendt, Jenny; Erzinger, Jörg; Kopf, Achim

    2014-01-01

    Integrated Ocean Drilling Program Expedition 338 was the second scientific expedition with D/V Chikyu during which riser drilling was conducted as part of the Nankai Trough Seismogenic Zone Experiment. Riser drilling enabled sampling and real-time monitoring of drilling mud gas with an onboard scientific drilling mud gas monitoring system ("SciGas"). A second, independent system was provided by Geoservices, a commercial mud logging service. Both systems allowed the determination of (non-) hydrocarbon gas, while the SciGas system also monitored the methane carbon isotope ratio (δ(13)CCH4). The hydrocarbon gas composition was predominated by methane (> 1%), while ethane and propane were up to two orders of magnitude lower. δ(13)CCH4 values suggested an onset of thermogenic gas not earlier than 1600 meter below seafloor. This study aims on evaluating the onboard data and subsequent geological interpretations by conducting shorebased analyses of drilling mud gas samples. During shipboard monitoring of drilling mud gas the SciGas and Geoservices systems recorded up to 8.64% and 16.4% methane, respectively. Ethane and propane concentrations reached up to 0.03 and 0.013%, respectively, in the SciGas system, but 0.09% and 0.23% in the Geoservices data. Shorebased analyses of discrete samples by gas chromatography showed a gas composition with ~0.01 to 1.04% methane, 2 - 18 ppmv ethane, and 2 - 4 ppmv propane. Quadruple mass spectrometry yielded similar results for methane (0.04 to 4.98%). With δD values between -171‰ and -164‰, the stable hydrogen isotopic composition of methane showed little downhole variability. Although the two independent mud gas monitoring systems and shorebased analysis of discrete gas sample yielded different absolute concentrations they all agree well with respect to downhole variations of hydrocarbon gases. The data point to predominantly biogenic methane sources but suggest some contribution from thermogenic sources at depth, probably due

  18. Monitoring pulmonary function with superimposed pulmonary gas exchange curves from standard analyzers.

    Science.gov (United States)

    Zar, Harvey A; Noe, Frances E; Szalados, James E; Goodrich, Michael D; Busby, Michael G

    2002-01-01

    A repetitive graphic display of the single breath pulmonary function can indicate changes in cardiac and pulmonary physiology brought on by clinical events. Parallel advances in computer technology and monitoring make real-time, single breath pulmonary function clinically practicable. We describe a system built from a commercially available airway gas monitor and off the shelf computer and data-acquisition hardware. Analog data for gas flow rate, O2, and CO2 concentrations are introduced into a computer through an analog-to-digital conversion board. Oxygen uptake (VO2) and carbon dioxide output (VCO2) are calculated for each breath. Inspired minus expired concentrations for O2 and CO2 are displayed simultaneously with the expired gas flow rate curve for each breath. Dead-space and alveolar ventilation are calculated for each breath and readily appreciated from the display. Graphs illustrating the function of the system are presented for the following clinical scenarios; upper airway obstruction, bronchospasm, bronchopleural fistula, pulmonary perfusion changes and inadequate oxygen delivery. This paper describes a real-time, single breath pulmonary monitoring system that displays three parameters graphed against time: expired flow rate, oxygen uptake and carbon dioxide production. This system allows for early and rapid recognition of treatable conditions that may lead to adverse events without any additional patient measurements or invasive procedures. Monitoring systems similar to the one described in this paper may lead to a higher level of patient safety without any additional patient risk.

  19. Testing of a prototype of calibration facility for noble gas monitoring using 41Ar

    International Nuclear Information System (INIS)

    Saibathulham, Holnisar; Wurdiyanto, Gatot; Marsum, Pujadi

    2012-01-01

    A prototype of a calibration facility for noble gas monitoring using 41 Ar in the PTKMR-BATAN has been tested. The facility was designed in such a way that the standard source of gas can be reused. The radioactive 41 Ar source was obtained by thermal neutron reaction of 40 Ar(n, γ) 41 Ar using a thermal neutron flux of 4.8×10 13 neutrons per cm 2 per second in two minutes on the multipurpose G.A. Siwabessy Reactor (Batan, Serpong, Indonesia). Gamma spectrometry was used to measure the radioactivity and purity of 41 Ar. The spectrum of the 41 Ar observed yields an energy of 1294 keV because of the highest intensity (99.2%). The activity of 41 Ar was 2821 kBq and 4% of the expanded uncertainty. The time required for 41 Ar to reach homogeneity was 7 min, and the effectiveness of resuse was 53%. - Highlights: ► Testing of a calibration facility prototype for noble gas monitor using 41 Ar in PTKMR-BATAN. ► This facility was designed such that a standard radioactive gas source can be used repeatedly. ► Standardization of the 41 Ar is performed using gamma spectrometry. ► The time required for the 41 Ar gas to be distributed evenly throughout the cavity of the facility was 7 min. ► The effectiveness of repeated use was 53%.

  20. Faults as Windows to Monitor Gas Seepage: Application to CO2 Sequestration and CO2-EOR

    Directory of Open Access Journals (Sweden)

    Ronald W. Klusman

    2018-03-01

    Full Text Available Monitoring of potential gas seepage for CO2 sequestration and CO2-EOR (Enhanced Oil Recovery in geologic storage will involve geophysical and geochemical measurements of parameters at depth and at, or near the surface. The appropriate methods for MVA (Monitoring, Verification, Accounting are needed for both cost and technical effectiveness. This work provides an overview of some of the geochemical methods that have been demonstrated to be effective for an existing CO2-EOR (Rangely, CA, USA and a proposed project at Teapot Dome, WY, USA. Carbon dioxide and CH4 fluxes and shallow soil gas concentrations were measured, followed by nested completions of 10-m deep holes to obtain concentration gradients. The focus at Teapot Dome was the evaluation of faults as pathways for gas seepage in an under-pressured reservoir system. The measurements were supplemented by stable carbon and oxygen isotopic measurements, carbon-14, and limited use of inert gases. The work clearly demonstrates the superiority of CH4 over measurements of CO2 in early detection and quantification of gas seepage. Stable carbon isotopes, carbon-14, and inert gas measurements add to the verification of the deep source. A preliminary accounting at Rangely confirms the importance of CH4 measurements in the MVA application.

  1. Making sense of monitoring data using Jupyter Notebooks: a case study of dissolved oxygen dynamics across a fresh-estuarine gradient

    Science.gov (United States)

    Nelson, N.; Munoz-Carpena, R.

    2016-12-01

    In the presented exercise, students (advanced undergraduate-graduate) explore dissolved oxygen (DO) dynamics at three locations along a fresh-estuarine gradient of the Lower St. Johns River, FL (USA). Spatiotemporal DO trends along this gradient vary as a function of (1) tidal influence, and (2) biotic productivity (phytoplankton photosynthesis and community respiration). This combination of influences produces distinct DO behavior across each of the three hydrologically-connected sites. Through analysis of high frequency monitoring data, students are encouraged to think critically about the roles of physical and biological drivers of DO, and how the relative importance of these factors can vary among different locations within a single tidal waterbody. Data from each of the three locations along the river are downloaded with CUAHSI HydroClient, and analysis is performed with a Python-enabled Jupyter Notebook that has been specifically created for this assignment. Jupyter Notebooks include annotated code organized into blocks that are executed one-at-a-time; this format is amenable to classroom teaching, and provides an approachable introduction to Python for inexperienced coders. The outputs from each code block (i.e. graphs, tables) are produced within the Jupyter Notebook, thus allowing students to directly interact with the code. Expected student learning outcomes include increased spatial reasoning, as well as greater understanding of DO cycling, spatiotemporal variability in tidal systems, and challenges associated with collecting and evaluating large data sets. Specific technical learning outcomes include coding in Python for data management and analysis using Jupyter notebooks. This assignment and associated materials are open-access and available on the Science Education Resource Center website.

  2. Monitoring of conditions inside gas aggregation cluster source during production of Ti/TiOx nanoparticles

    Science.gov (United States)

    Kousal, J.; Kolpaková, A.; Shelemin, A.; Kudrna, P.; Tichý, M.; Kylián, O.; Hanuš, J.; Choukourov, A.; Biederman, H.

    2017-10-01

    Gas aggregation sources are nowadays rather widely used in the research community for producing nanoparticles. However, the direct diagnostics of conditions inside the source are relatively scarce. In this work, we focused on monitoring the plasma parameters and the composition of the gas during the production of the TiOx nanoparticles. We studied the role of oxygen in the aggregation process and the influence of the presence of the particles on the plasma. The construction of the source allowed us to make a 2D map of the plasma parameters inside the source.

  3. A simple nondestructive technique for monitoring the bond gas in sealed fast reactor nuclear fuel pins

    Energy Technology Data Exchange (ETDEWEB)

    Shriwastwa, B B; Mehrotra, R S; Ghosh, J K [Bhabha Atomic Research Centre, Bombay (India). Radiometallurgy Div.

    1994-12-31

    A simple nondestructive testing technique has been developed to identify bond gas inside a welded fuel pin. The technique is based on the accurate surface temperature measurement of fuel pins heated in a constant temperature water bath. This technique can be applied in Fast Breeder Test Reactor (FBTR) fuel pin production line due to simplicity of the set up, simple operation and quick response time. An attempt was made to develop a non destructive test method for monitoring the bond gas composition. Preliminary development work carried out in this connection, the test method adopted and the test results are presented. 1 ref., 5 figs., 1 tab.

  4. Continuous gas monitoring in the West Bohemian earthquake area, Czech Republic: First results

    Czech Academy of Sciences Publication Activity Database

    Faber, E.; Horálek, Josef; Boušková, Alena; Teschner, M.; Koch, U.; Poggenburg, J.

    2009-01-01

    Roč. 53, č. 3 (2009), s. 315-328 ISSN 0039-3169 R&D Projects: GA ČR(CZ) GA205/06/1780 Grant - others:German Ministry of Economics and Labour(DE) BMWi VI A 2-27/01 Institutional research plan: CEZ:AV0Z30120515 Keywords : West Bohemian earthquake area * earthquake swarms * gas monitoring * soil gas * carbon dioxide * radon * mofette * time series Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.000, year: 2009

  5. Measurements made in the SPS with a rest gas profile monitor by collecting electrons

    International Nuclear Information System (INIS)

    Fischer, C.; Koopman, J.

    2000-01-01

    Measurements have regularly been performed during the 1999 run, using the Rest Gas Monitor installed in the SPS. The exploited signal resulted from electrons produced by ionization of the rest gas during the circulating beam passage. A magnetic field parallel to the electric extraction field was applied to channel the electrons. Proton beam horizontal transverse distributions were recorded during entire SPS acceleration cycles, between 14 GeV/c and 450 GeV/c and for different beam structures and bunch intensities. The influence of several parameters on the measured beam profiles was investigated. Results are presented and analyzed in order to determine the performance that can be expected

  6. Gas Hydrate Occurrence Inferred from Dissolved Cl− Concentrations and δ18O Values of Pore Water and Dissolved Sulfate in the Shallow Sediments of the Pockmark Field in Southwestern Xisha Uplift, Northern South China Sea

    Directory of Open Access Journals (Sweden)

    Min Luo

    2014-06-01

    Full Text Available Deep-water pockmarks are frequently accompanied by the occurrence of massive gas hydrates in shallow sediments. A decline in pore-water Cl− concentration and rise in δ18O value provide compelling evidence for the gas hydrate dissociation. Mega-pockmarks are widely scattered in the southwestern Xisha Uplift, northern South China Sea (SCS. Pore water collected from a gravity-core inside of a mega-pockmark exhibits a downward Cl− concentration decrease concomitant with an increase in δ18O value at the interval of 5.7–6.7 mbsf. Concentrations of Cl−, Na+, and K+ mainly cluster along the seawater freshening line without distinct Na+ enrichment and K+ depletion. Thus, we infer that the pore water anomalies of Cl− concentrations and δ18O values are attributed to gas hydrate dissociation instead of clay mineral dehydration. Moreover, the lower δ18O values of sulfate in the target core (C14 than those in the reference core (C9 may be associated with the equilibrium oxygen fractionation during sulfate reduction between sulfate and the relatively 18O-depleted ambient water resulting from gas hydrate formation. The gas hydrate contents are estimated to be 6%–10% and 7%–15%, respectively, according to the offset of Cl− concentrations and δ18O values from the baselines. This pockmark field in southwestern Xisha Uplift is likely to be a good prospective area for the occurrence of gas hydrate in shallow sediments.

  7. On-line sodium and cover as purity monitors gas operating tools at EBR-II

    International Nuclear Information System (INIS)

    Smith, C.R.F.; Richardson, W.J.; Holmes, J.T.

    1976-01-01

    Plugging temperature indicators, electrochemical oxygen meters and hydrogen diffusion meters are the on-line sodium purity monitors now in use at EBR-II. On-line gas chromatographs are used to monitor helium, hydrogen, oxygen and nitrogen impurities in the argon cover gases. Monitors for tritium-in-sodium and for hydrocarbons-in-cover gas have been developed and are scheduled for installation in the near future. An important advantage of on-line monitors over the conventional grab-sampling techniques is the speed of response to changing reactor conditions. This helps us to identify the source of the impurity, whether the cause may be transient or constant, and take corrective action as necessary. The oxygen meter is calibrated monthly against oxygen in sodium determined by the vanadium wire equilibration method. The other instruments either do not require calibration or are self-calibrating. The ranges, sensitivity and response times of all of the on-line purity monitors has proven satisfactory under EBR-II operating conditions

  8. R & D of a Gas-Filled RF Beam Profile Monitor for Intense Neutrino Beam Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Yonehara, K. [Fermilab; Backfish, M. [Fermilab; Moretti, A. [Fermilab; Tollestrup, A. V. [Fermilab; Watts, A. [Fermilab; Zwaska, R. M. [Fermilab; Abrams, R. [MUONS Inc., Batavia; Cummings, M. A.; Dudas, A. [MUONS Inc., Batavia; Johnson, R. P. [MUONS Inc., Batavia; Kazakevich, G. [MUONS Inc., Batavia; Neubauer, M. [MUONS Inc., Batavia; Liu, Q. [Case Western Reserve U.

    2017-05-01

    We report the R&D of a novel radiation-robust hadron beam profile monitor based on a gas-filled RF cavity for intense neutrino beam experiments. An equivalent RF circuit model was made and simulated to optimize the RF parameter in a wide beam intensity range. As a result, the maximum acceptable beam intensity in the monitor is significantly increased by using a low-quality factor RF cavity. The plan for the demonstration test is set up to prepare for future neutrino beam experiments.

  9. Design and performance of a skid-mounted portable compartment fire gas furnace and monitoring system

    Directory of Open Access Journals (Sweden)

    Mueller K.

    2013-09-01

    Full Text Available A custom, portable natural gas fire furnace was designed and constructed for use at the University of Notre Dame to experimentally investigate the out-of-plane behavior of full-scale reinforced concrete (RC bearing walls under fire. The unique aspects of this furnace allowed the application of large mechanical loads and non-contact optical response monitoring to be done while subjecting the wall to elevated temperatures. The performance of the experimental furnace, mechanical loading, and response monitoring system is reported using the results from the first two RC wall test specimens.

  10. The Potential Applications of Real-Time Monitoring of Water Quality in a Large Shallow Lake (Lake Taihu, China) Using a Chromophoric Dissolved Organic Matter Fluorescence Sensor

    OpenAIRE

    Niu, Cheng; Zhang, Yunlin; Zhou, Yongqiang; Shi, Kun; Liu, Xiaohan; Qin, Boqiang

    2014-01-01

    This study presents results from field surveys performed over various seasons in a large, eutrophic, shallow lake (Lake Taihu, China) using an in situ chromophoric dissolved organic matter (CDOM) fluorescence sensor as a surrogate for other water quality parameters. These measurements identified highly significant empirical relationships between CDOM concentration measured using the in situ fluorescence sensor and CDOM absorption, fluorescence, dissolved organic carbon (DOC), chemical oxygen ...

  11. Radon baseline monitoring around a potential shale gas development site in Yorkshire, England

    International Nuclear Information System (INIS)

    Daraktchieva, Z.; Wasikiewicz, J. M.; Howarth, C. B.; Bradley, E.J.

    2017-01-01

    The Vale of Pickering in Yorkshire, England has been identified as a potential area for shale gas extraction. Public Health England joined a collaboration led by the British Geological Survey for environmental baseline monitoring near the potential shale gas extraction site following a grant award from UK Government Department for Business, Energy and Industrial Strategy. The analysis of results for the first 6 months of indoor monitoring indicated that the results followed a log-normal distribution. The numbers of homes found to be at or above the Action Level followed the numbers predicted by the radon potential maps. The results from the measurements of outdoor air in this study indicated that the radon concentrations are slightly higher than previously measured but close to the detection limit of the technique. (authors)

  12. RADON BASELINE MONITORING AROUND A POTENTIAL SHALE GAS DEVELOPMENT SITE IN YORKSHIRE, ENGLAND.

    Science.gov (United States)

    Daraktchieva, Z; Wasikiewicz, J M; Howarth, C B; Bradley, E J

    2017-11-01

    The Vale of Pickering in Yorkshire, England has been identified as a potential area for shale gas extraction. Public Health England joined a collaboration led by the British Geological Survey for environmental baseline monitoring near the potential shale gas extraction site following a grant award from UK Government Department for Business, Energy and Industrial Strategy. The analysis of results for the first 6 months of indoor monitoring indicated that the results followed a log-normal distribution. The numbers of homes found to be at or above the Action Level followed the numbers predicted by the radon potential maps. The results from the measurements of outdoor air in this study indicated that the radon concentrations are slightly higher than previously measured but close to the detection limit of the technique. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Optical Multi-Gas Monitor Technology Demonstration on the International Space Station

    Science.gov (United States)

    Pilgrim, Jeffrey S.; Wood, William R.; Casias, Miguel E.; Vakhtin, Andrei B,; Johnson, Michael D.; Mudgett, Paul D.

    2014-01-01

    There are a variety of both portable and fixed gas monitors onboard the International Space Station (ISS). Devices range from rack-mounted mass spectrometers to hand-held electrochemical sensors. An optical Multi-Gas Monitor has been developed as an ISS Technology Demonstration to evaluate long-term continuous measurement of 4 gases. Based on tunable diode laser spectroscopy, this technology offers unprecedented selectivity, concentration range, precision, and calibration stability. The monitor utilizes the combination of high performance laser absorption spectroscopy with a rugged optical path length enhancement cell that is nearly impossible to misalign. The enhancement cell serves simultaneously as the measurement sampling cell for multiple laser channels operating within a common measurement volume. Four laser diode based detection channels allow quantitative determination of ISS cabin concentrations of water vapor (humidity), carbon dioxide, ammonia and oxygen. Each channel utilizes a separate vertical cavity surface emitting laser (VCSEL) at a different wavelength. In addition to measuring major air constituents in their relevant ranges, the multiple gas monitor provides real time quantitative gaseous ammonia measurements between 5 and 20,000 parts-per-million (ppm). A small ventilation fan draws air with no pumps or valves into the enclosure in which analysis occurs. Power draw is only about 3 W from USB sources when installed in Nanoracks or when connected to 28V source from any EXPRESS rack interface. Internal battery power can run the sensor for over 20 hours during portable operation. The sensor is controlled digitally with an FPGA/microcontroller architecture that stores data internally while displaying running average measurements on an LCD screen and interfacing with the rack or laptop via USB. Design, construction and certification of the Multi-Gas Monitor were a joint effort between Vista Photonics, Nanoracks and NASA-Johnson Space Center (JSC

  14. Methods to produce calibration mixtures for anesthetic gas monitors and how to perform volumetric calculations on anesthetic gases.

    Science.gov (United States)

    Christensen, P L; Nielsen, J; Kann, T

    1992-10-01

    A simple procedure for making calibration mixtures of oxygen and the anesthetic gases isoflurane, enflurane, and halothane is described. One to ten grams of the anesthetic substance is evaporated in a closed, 11,361-cc glass bottle filled with oxygen gas at atmospheric pressure. The carefully mixed gas is used to calibrate anesthetic gas monitors. By comparison of calculated and measured volumetric results it is shown that at atmospheric conditions the volumetric behavior of anesthetic gas mixtures can be described with reasonable accuracy using the ideal gas law. A procedure is described for calculating the deviation from ideal gas behavior in cases in which this is needed.

  15. Triple GEM gas detectors as real time fast neutron beam monitors for spallation neutron sources

    International Nuclear Information System (INIS)

    Murtas, F; Claps, G; Croci, G; Tardocchi, M; Pietropaolo, A; Cippo, E Perelli; Rebai, M; Gorini, G; Frost, C D; Raspino, D; Rhodes, N J; Schooneveld, E M

    2012-01-01

    A fast neutron beam monitor based on a triple Gas Electron Multiplier (GEM) detector was developed and tested for the ISIS spallation neutron source in U.K. The test on beam was performed at the VESUVIO beam line operating at ISIS. The 2D fast neutron beam footprint was recorded in real time with a spatial resolution of a few millimeters thanks to the patterned detector readout.

  16. Laser Spectroscopy Multi-Gas Monitor: Results of Technology Demonstration on ISS

    Science.gov (United States)

    Mudgett, Paul D.; Pilgrim, Jeffrey S.

    2015-01-01

    Tunable diode laser spectroscopy (TDLS) is an up and coming trace and major gas monitoring technology with unmatched selectivity, range and stability. The technology demonstration of the 4 gas Multi-Gas Monitor (MGM), reported at the 2014 ICES conference, operated continuously on the International Space Station (ISS) for nearly a year. The MGM is designed to measure oxygen, carbon dioxide, ammonia and water vapor in ambient cabin air in a low power, relatively compact device. While on board, the MGM experienced a number of challenges, unplanned and planned, including a test of the ammonia channel using a commercial medical ammonia inhalant. Data from the unit was downlinked once per week and compared with other analytical resources on board, notably the Major Constituent Analyzer (MCA), a magnetic sector mass spectrometer. MGM spent the majority of the time installed in the Nanoracks Frame 2 payload facility in front breathing mode (sampling the ambient environment of the Japanese Experiment Module), but was also used to analyze recirculated rack air. The capability of the MGM to be operated in portable mode (via internal rechargeable lithium ion polymer batteries or by plugging into any Express Rack 28VDC connector) was a part of the usability demonstration. Results to date show unprecedented stability and accuracy of the MGM vs. the MCA for oxygen and carbon dioxide. The ammonia challenge (approx. 75 ppm) was successful as well, showing very rapid response time in both directions. Work on an expansion of capability in a next generation MGM has just begun. Combustion products and hydrazine are being added to the measurable target analytes. An 8 to 10 gas monitor (aka Gas Tricorder 1.0) is envisioned for use on ISS, Orion and Exploration missions.

  17. Pollution Monitoring System Using Gas Sensor based on Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    M. Udin Harun Al Rasyid

    2016-01-01

    Full Text Available Carbon monoxide (CO and carbon dioxide (CO2 gases are classified as colorless and odorless gas so we need special tools to monitor their concentration in the air. Concentration of air pollution of CO and CO2 that are high in the air will give serious effects for health status. CO is a poisonous gas that damages the circulation of oxygen in the blood when inhaled, while CO2 is one of the gases that causes global warming. In this paper, we developed an integrated pollution monitoring (IPOM system to monitor the concentration of air pollution. This research implemented three sensor nodes (end-device which each node contains CO and CO2 sensors on the gas sensors board to perform sensing from the environment. Furthermore, the data taken from the environment by the sensor will be sent to the meshlium gateway using IEEE 802.15.4 Zigbee communications and processed by the gateway in order to be sent to the computer server. The data is stored in meshlium gateway using MySQL database as a backup, and it will be synchronized to the MySQL database in the computer server. We provide services for public to access the information in database server through a desktop and website application.

  18. A new method research of monitoring low concentration NO and SO2 mixed gas

    Science.gov (United States)

    Bo, Peng; Gao, Chao; Guo, Yongcai; Chen, Fang

    2018-01-01

    In order to reduce the pollution of the environment, China has implemented a new ultra-low emission control regulations for polluting gas, requiring new coal-fired power plant emissions SO2 less than 30ppm, NO less than 75ppm, NO2 less than 50ppm, Monitoring low concentration of NO and SO2 mixed gases , DOAS technology facing new challenges, SO2 absorb significantly weaken at the original absorption peak, what more the SNR is very low, it is difficult to extract the characteristic signal, and thus cannot obtain its concentration. So it cannot separate the signal of NO from the mixed gas at the wavelength of 200 230nm through the law of spectral superposition, it cannot calculate the concentration of NO. The classical DOAS technology cannot meet the needs of monitoring. In this paper, we found another absorption spectrum segment of SO2, the SNR is 10 times higher than before, Will not be affected by NO, can calculate the concentration of SO2 accurately, A new method of segmentation and demagnetization separation technology of spectral signals is proposed, which achieves the monitoring the low concentration mixed gas accurately. This function cannot be achieved by the classical DOAS. Detection limit of this method is 0.1ppm per meter which is higher than before, The relative error below 5% when the concentration between 0 5ppm, the concentration of NO between 6 75ppm and SO2 between 6 30ppm the relative error below 1.5%, it has made a great breakthrough In the low concentration of NO and SO2 monitoring. It has great scientific significance and reference value for the development of coal-fired power plant emission control, atmospheric environmental monitoring and high-precision on-line instrumentation.

  19. Development of an online biosensor for in situ monitoring of chlorine dioxide gas disinfection efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Del Busto-Ramos, M.; Budzik, M.; Corvalan, C.; Morgan, M.; Nivens, D.; Applegate, B. [Purdue Univ., West Lafayette, IN (United States). Dept. of Food Science; Turco, R. [Purdue Univ., West Lafayette, IN (United States). Dept. of Agronomy

    2008-03-15

    A prototype bioluminescence-based biosensor was designed and constructed to evaluate the antimicrobial efficacy of chlorine dioxide (ClO{sub 2}) gas under various treatment conditions. The biosensor consisted of a bioluminescent bioreporter (Pseudomonas fluorescens 5RL), an optical transducer (photomultiplier tube), and a light-tight chamber housing, the bioreporter and the transducer. The bioluminescent recombinant P. fluorescens 5RL in the biosensor allowed for online monitoring of bioluminescence during ClO{sub 2} gas disinfection. Experiments were performed to evaluate the effects of the two key physical parameters associated with ClO{sub 2} disinfection: relative humidity (40, 60, 80%) and ClO{sub 2} gas concentration (0.5, 1.0, 1.6, 2.1 mg/l) on the bioreporter. Results showed that increasing concentrations of ClO{sub 2} gas corresponded to a faster decrease in luminescence. The rates of luminescence decrease from P. fluorescens 5RL, and the log reduction time (LRT, time required to obtain 1-log reduction in luminescence) were calculated for each treatment tested. The LRT values of luminescence were 103, 78, 53, and 35 s for 0.5, 1.0, 1.6, and 2.1 mg/l of ClO{sub 2} gas treatment, respectively, at 78% relative humidity. The gas concentration which caused a tenfold change in LRT (z value) for luminescence of P. fluorescens 5RL was 3.4 mg/l of ClO{sub 2}. The prototype biosensor showed potential for many applications, such as monitoring real-time microbial inactivation and understanding parameters that influence the efficacy of gaseous decontamination procedures. (orig.)

  20. Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in COAL IGCC Powerplants

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth A. Yackly

    2004-09-30

    The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, has been re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for Coal IGCC powerplants. The new program has been re-titled as ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants'' to better match the new scope. This technical progress report summarizes the work accomplished in the reporting period April 1, 2004 to August 31, 2004 on the revised Re-Directed and De-Scoped program activity. The program Tasks are: Task 1--IGCC Environmental Impact on high Temperature Materials: This first materials task has been refocused to address Coal IGCC environmental impacts on high temperature materials use in gas turbines and remains in the program. This task will screen material performance and quantify the effects of high temperature erosion and corrosion of hot gas path materials in Coal IGCC applications. The materials of interest will include those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: This second task develops and demonstrates new sensor technologies to determine the in-service health of advanced technology Coal IGCC powerplants, and remains in the program with a reduced scope. Its focus is now on only two critical sensor need areas for advanced Coal IGCC gas turbines: (1) Fuel Quality Sensor for detection of fuel impurities that could lead to rapid component degradation, and a Fuel Heating Value Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware.

  1. Measurement and interpretation of low levels of dissolved oxygen in ground water

    Science.gov (United States)

    White, A.F.; Peterson, M.L.; Solbau, R.D.

    1990-01-01

    A Rhodazine-D colorimetric technique was adapted to measure low-level dissolved oxygen concentrations in ground water. Prepared samples containing between 0 and 8.0 ??moles L-1 dissolved oxygen in equilibrium with known gas mixtures produced linear spectrophotometric absorbance with a lower detection limit of 0.2 ??moles L-1. Excellent reproducibility was found for solutions ranging in composition from deionized water to sea water with chemical interferences detected only for easily reduced metal species such as ferric ion, cupric ion, and hexavalent chromium. Such effects were correctable based on parallel reaction stoichiometries relative to oxygen. The technique, coupled with a downhole wire line tool, permitted low-level monitoring of dissolved oxygen in wells at the selenium-contaminated Kesterson Reservoir in California. Results indicated a close association between low but measurable dissolved oxygen concentrations and mobility of oxidized forms of selenium. -from Authors

  2. One year continuous soil gas monitoring above an EGR test site

    Science.gov (United States)

    Furche, Markus; Schlömer, Stefan; Faber, Eckhard; Dumke, Ingolf

    2010-05-01

    Setup and first results of an ongoing research activity are presented, which is funded by the German Geotechnologien program within in the joint project CLEAN (CO2 Large Scale Enhanced Gas Recovery in the Altmark Natural Gas Field). The task is to establish several soil gas monitoring stations above a partly exhausted gas field in the Altmark which will be used for an enhanced gas recovery (EGR) test by injecting CO2 into the reservoir. The aim is to optimize the monitoring technique including automatic data transfer and data exploitation and to understand mechanisms of natural variations of soil gas concentrations in the specific area. Furthermore the suitability of these measurements as a contribution to leakage detection shall be evaluated. A network of 13 gauging stations for the measurement of CO2 is working continuously for about one year. They are spread over an area of 8 x 3 km and are situated in direct vicinity of existing deep boreholes as the most likely locations for possible leakage. In addition one station is placed far outside the gasfield as a reference point. The technique applied to measure soil gas concentrations uses a gas stream circulating in a tube going down a shallow borehole where the circulating gas is in contact with the soil gas phase via a gas permeable membrane. Above surface, moisture is removed from the gas stream before it reaches several gas sensors for CO2. Besides these, several other parameters are determined as well, e.g. soil moisture and soil temperature, water level, gas flow and gas moisture. In addition a meteorological station gives information about precipitation, air humidity, temperature and pressure, global radiation, wind direction and velocity in the area. Data are continuously collected by dataloggers at each station (5 minutes interval), transferred via GSM routers to the BGR server in Hannover and are stored in a specially designed database. The database does not only contain the measurements but also

  3. Characteristics of Noble Gas-filled Ionization Chambers for a Low Dose Rate Monitoring

    International Nuclear Information System (INIS)

    Kim, Han Soo; Park, Se Hwan; Ha, Jan Ho; Lee, Jae Hyung; Lee, Nam Ho; Kim, Jung Bok; Kim, Yong Kyun; Kim, Do Hyun; Cho, Seung Yeon

    2007-01-01

    An ionization chamber is still widely used in fields such as an environmental radiation monitoring, a Radiation Monitoring System (RMS) in nuclear facilities, and an industrial application due to its operational stability for a long period and its designs for its applications. Ionization chambers for RMS and an environmental radiation monitoring are requested to detect a low dose rate at as low as 10-2 mR/h and several 3R/h, respectively. Filling gas and its pressure are two of the important factors for an ionization chamber development to use it in these fields, because these can increase the sensitivity of an ionization chamber. We developed cylindrical and spherical ionization chambers for a low dose rate monitoring. Response of a cylindrical ionization chamber, which has a 1 L active volume, was compared when it was filled with Air, Ar, and Xe gas respectively. Response of a spherical ionization chamber was also compared in the case of 9 atm and 25 atm filling-pressures. An inter-comparison with a commercially available high pressure Ar ionization chamber and a fabricated ionization chamber was also performed. A High Pressure Xenon (HPXe) ionization chamber, which was configured with a shielding mesh to eliminate an induced charge of positive ions, was fabricated both for the measurement of an environmental dose rate and for the measurement of an energy spectrum

  4. Evaluation of the RSG-GAS Alpha-Beta Aerosol Contaminant Monitor Performance Under Reactor Operation Condition

    International Nuclear Information System (INIS)

    Hartoyo, Unggul; Setiawanto, Anto; Sumarno, Yulius

    2000-01-01

    Analysis to evaluate the RSG-GAS alpha-beta aerosol contaminant monitor performance was done. The high potential radiation working area such as in RSG-GAS is important to monitored for personal safety. Further it is necessary to assure that the system monitor is reliable enough under normal conditions as well as emergency condition. The method uses in this analysis are monitoring and comparing with the standard source. The standard course indicator and panel in main control room indicate that the result is 1 x 110 exp 9 Ci/m exp 3. Based on data monitor observation, the RSG-GAS alpha-beta aerosol contaminant monitor system under reactor operation condition has a good enough performance

  5. Barometric gas transport along faults and its application to nuclear test-ban monitoring

    International Nuclear Information System (INIS)

    Carrigan, C.R.; Heinle, R.A.; Hudson, G.M.; Nitao, J.J.; Zucca, J.J.

    1997-05-01

    Underground nuclear explosions produce a unique but evanescent set of radionuclide gases that potentially can be used in the context of an on-site, test-ban monitoring program to differentiate them from other detected events such as earthquakes or mining activity. In Part I of this report we describe an experiment to evaluate the upward transport of gases from an underground explosion using two gas tracers with very different diffusivities that were released in a 400-m-deep, chemical explosive detonation. The less diffusive (more massive) tracer was detected on a nearby geologic fault 50 days following the detonation while the more diffusive tracer was detected 375 days after release. Computer simulations indicate that the arrival time and the chromatographic behavior of transport are characteristic of barometrically induced flow in a fractured, porous matrix regime. For a hypothetical 1-kiloton fission explosion subject to the same weather and gas transport conditions of the chemical explosion, simulations predict the detectability of argon-37 after 80 days in spite of depletion by radioactive decay. Largely because of the earlier arrival of xenon-133, owing to its lower binary gas diffusivity, the exceedingly short lived isotope should also be detectable - arriving about 30 days earlier than argon. In Part II we consider that our prediction of the detectability of argon and xenon is based upon the small volume (0.00001 m 3 ) sampling technique of the NPE tracer-gas sampling study while actual sampling for radionuclides would involve drawing much larger volume (possibly 0.1-1 m 3 ) gas samples from the near-surface. Extraction of such a large volume of gas from 1-5 meter depths in the soil raises the possibility of significant atmospheric infiltration, leading to substantial dilution of the extracted gas sample. However, an infiltration experiment suggests that significant dilution would not, in fact, occur at the most prolific sampling stations of the earlier gas

  6. On-Line Fission Gas Release Monitoring System in the High Flux Reactor Petten

    International Nuclear Information System (INIS)

    Laurie, M.; Fuetterer, M. A.; Appelman, K.H.; Lapetite, J.-M.; Marmier, A.; Knol, S.; Best, J.

    2013-06-01

    For HTR fuel irradiation tests in the HFR Petten a specific installation was designed and installed dubbed the 'Sweep Loop Facility' (SLF). The SLF is tasked with three functions, namely temperature control by gas mixture technique, surveillance of safety parameters (temperature, pressure, radioactivity etc.) and analysis of fission gas release for three individual capsules in two separate experimental rigs. The SLF enables continuous and independent surveillance of all gas circuits. The release of volatile fission products (FP) from the in-pile experiments is monitored by continuous gas purging. The fractional release of these FP, defined as the ratio between release rate of a gaseous fission isotope (measured) to its instantaneous birth rate (calculated), is a licensing-relevant test for HTR fuel. The developed gamma spectrometry station allows for higher measurement frequencies, thus enabling follow-up of rapid and massive release transients. The designed stand-alone system was tested and fully used through the final irradiation period of the HFR-EU1 experiment which was terminated on 18 February 2010. Its robustness allowed the set up to be used as extra safety instrumentation. This paper describes the gas activity measurement technique based on HPGe gamma spectrometry and illustrates how qualitative and quantitative analysis of volatile FP can be performed on-line. (authors)

  7. Long-term monitoring of soil gas fluxes with closed chambers using automated and manual systems

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A.; Crichton, I.; Ball, B.C.

    1999-10-01

    The authors describe two gas sample collection techniques, each of which is used in conjunction with custom made automated or manually operated closed chambers. The automated system allows automatic collection of gas samples for simultaneous analysis of multiple trace gas efflux from soils, permitting long-term monitoring. Since the manual system is cheaper to produce, it can be replicated more than the automated and used to estimate spatial variability of soil fluxes. The automated chamber covers a soil area of 0.5 m{sup 2} and has a motor driven lid that remains operational throughout a range of weather conditions. Both systems use gas-tight containers of robust metal construction, which give good sample retention, thereby allowing long-term storage and convenience of transport from remote locations. The containers in the automated system are filled by pumping gas from the closed chamber via a multiway rotary valve. Stored samples from both systems are analyzed simultaneously for N{sub 2}O and CO{sub 2} using automated injection into laboratory-based gas chromatographs. The use of both collection systems is illustrated by results from a field experiment on sewage sludge disposal to land where N{sub 2}O fluxes were high. The automated gas sampling system permitted quantification of the marked temporal variability of concurrent N{sub 2}O and CO{sub 2} fluxes and allowed improved estimation of cumulative fluxes. The automated measurement approach yielded higher estimates of cumulative flux because integration of manual point-in-time observations missed a number of transient high-flux events.

  8. Gas Path Health Monitoring for a Turbofan Engine Based on a Nonlinear Filtering Approach

    Directory of Open Access Journals (Sweden)

    Yiqiu Lv

    2013-01-01

    Full Text Available Different approaches for gas path performance estimation of dynamic systems are commonly used, the most common being the variants of the Kalman filter. The extended Kalman filter (EKF method is a popular approach for nonlinear systems which combines the traditional Kalman filtering and linearization techniques to effectively deal with weakly nonlinear and non-Gaussian problems. Its mathematical formulation is based on the assumption that the probability density function (PDF of the state vector can be approximated to be Gaussian. Recent investigations have focused on the particle filter (PF based on Monte Carlo sampling algorithms for tackling strong nonlinear and non-Gaussian models. Considering the aircraft engine is a complicated machine, operating under a harsh environment, and polluted by complex noises, the PF might be an available way to monitor gas path health for aircraft engines. Up to this point in time a number of Kalman filtering approaches have been used for aircraft turbofan engine gas path health estimation, but the particle filters have not been used for this purpose and a systematic comparison has not been published. This paper presents gas path health monitoring based on the PF and the constrained extend Kalman particle filter (cEKPF, and then compares the estimation accuracy and computational effort of these filters to the EKF for aircraft engine performance estimation under rapid faults and general deterioration. Finally, the effects of the constraint mechanism and particle number on the cEKPF are discussed. We show in this paper that the cEKPF outperforms the EKF, PF and EKPF, and conclude that the cEKPF is the best choice for turbofan engine health monitoring.

  9. Results of a Long-Term Demonstration of an Optical Multi-Gas Monitor on ISS

    Science.gov (United States)

    Mudgett, Paul; Pilgrim, Jeffrey S.

    2015-01-01

    Previously at SAMAP we reported on the development of tunable diode laser spectroscopy (TDLS) based instruments for measuring small gas molecules in real time. TDLS technology has matured rapidly over the last 5 years as a result of advances in low power diode lasers as well as better detection schemes. In collaboration with two small businesses Vista Photonics, Inc. and Nanoracks LLC, NASA developed a 4 gas TDLS based monitor for an experimental demonstration of the technology on the International Space Station (ISS). Vista invented and constructed the core TDLS sensor. Nanoracks designed and built the enclosure, and certified the integrated monitor as a payload. The device, which measures oxygen, carbon dioxide, ammonia and water vapor, is called the Multi-Gas Monitor (MGM). MGM measures the 4 gases every few seconds and records a 30 second moving average of the concentrations. The relatively small unit draws only 2.5W. MGM was calibrated at NASA-Johnson Space Center in July 2013 and launched to ISS on a Soyuz vehicle in November 2013. Installation and activation of MGM occurred in February 2014, and the unit has been operating nearly continuously ever since in the Japanese Experiment Module. Data is downlinked from ISS about once per week. Oxygen and carbon dioxide data is compared with that from the central Major Constituents Analyzer. Water vapor data is compared with dew point measurements made by sensors in the Columbus module. The ammonia channel was tested by the crew using a commercial ammonia inhalant. MGM is remarkably stable to date. Results of 18 months of operation are presented and future applications including combustion product monitoring are discussed.

  10. On-line valve monitoring at the Ormen Lange gas plant

    Energy Technology Data Exchange (ETDEWEB)

    Greenlees, R.; Hale, S. [Score Atlanta Inc., Kennesaw, Georgia (United States)

    2011-07-01

    The purpose of this presentation is to discuss replacing time and labor intensive nuclear outage activities with on line condition monitoring solutions, primarily the periodic verification of MOV functionality discussed in USNRC Generic Letter 96.05. This regulation requires that MOV age related performance degradations are properly identified and accounted for, causing utilities to have to retest valves periodically for the duration of the plants operating license. AECL designed CANDU reactors have a world class performance and safety record, with typical average annual capacity factors of 90%. The CANDU reactor design has the ability to refuel on line, as a result (a) it can be a challenge scheduling all required valve testing into limited duration outage work windows, (b) at multi unit sites, Unit 0 valves can be difficult to test because they are rarely ever out of service, (c) deuterium-oxide (heavy water) moderator is expensive to manufacture, as a result, effective through valve leakage monitoring is essential. These three factors alone make CANDU sites the most suitable candidates for on line valve monitoring systems. Nuclear industry regulations have been instrumental in the development of 'at the valve' diagnostic systems, but diagnostic testing has not typically been utilized to the same degree in other less regulated industries. However, that trend is changing, and the move toward valve diagnostics and condition monitoring has moved fastest in the offshore oil and gas industry on the Norwegian side of the North Sea. The Ormen Lange plant, located on Nyhamna Island on the west coast of Norway, operated by Shell, is one of the worlds most advanced gas processing plants. A stated maintenance goal for the plant is that 70% of the maintenance budget and spend should be based on the results of on line condition monitoring, utilizing monitoring systems equipped with switch sensing, strain gages, hydraulic and pneumatic pressure transducers and

  11. On-line valve monitoring at the Ormen Lange gas plant

    International Nuclear Information System (INIS)

    Greenlees, R.; Hale, S.

    2011-01-01

    The purpose of this presentation is to discuss replacing time and labor intensive nuclear outage activities with on line condition monitoring solutions, primarily the periodic verification of MOV functionality discussed in USNRC Generic Letter 96.05. This regulation requires that MOV age related performance degradations are properly identified and accounted for, causing utilities to have to retest valves periodically for the duration of the plants operating license. AECL designed CANDU reactors have a world class performance and safety record, with typical average annual capacity factors of 90%. The CANDU reactor design has the ability to refuel on line, as a result (a) it can be a challenge scheduling all required valve testing into limited duration outage work windows, (b) at multi unit sites, Unit 0 valves can be difficult to test because they are rarely ever out of service, (c) deuterium-oxide (heavy water) moderator is expensive to manufacture, as a result, effective through valve leakage monitoring is essential. These three factors alone make CANDU sites the most suitable candidates for on line valve monitoring systems. Nuclear industry regulations have been instrumental in the development of 'at the valve' diagnostic systems, but diagnostic testing has not typically been utilized to the same degree in other less regulated industries. However, that trend is changing, and the move toward valve diagnostics and condition monitoring has moved fastest in the offshore oil and gas industry on the Norwegian side of the North Sea. The Ormen Lange plant, located on Nyhamna Island on the west coast of Norway, operated by Shell, is one of the worlds most advanced gas processing plants. A stated maintenance goal for the plant is that 70% of the maintenance budget and spend should be based on the results of on line condition monitoring, utilizing monitoring systems equipped with switch sensing, strain gages, hydraulic and pneumatic pressure transducers and acoustic leakage

  12. Development Of A Permanent Magnet Residual Gas Profile Monitor With Fast Readout

    CERN Document Server

    Barabin, S; Giacomini, T; Liakin, D; Orlov, A; Skachkov, V S

    2004-01-01

    The beam profile measurements at modern ion synchrotrons and storage rings require high timing performances on a turn-by-turn basis. On the other hand, high spatial resolutions are very desirable for cooled beams. We are developing a residual gas monitor to cover the wide range of beam intensities and dimensions. It supplies the needed high-resolution and high-speed tools for beam profiling. The new residual gas monitor will operate on scattered residual gas electrons whose trajectories are localized within 0.1 mm filaments by using appropriate magnetic field. The required magnetic field of 100 mT will be excited by either a permanent or an electromagnet. The high resolution mode of 0.1 mm is provided by a CCD camera with upstream MCP-phosphor screen assembly. In the fast turn-by-turn mode the beam profile will be read out with a resolution of 1 mm by a 100-channel photodiode-amplifier-digitizer, which will be explained in detail.

  13. Multi-detector system approach for unattended uranium enrichment monitoring at gas centrifuge enrichment plants

    Science.gov (United States)

    Favalli, A.; Lombardi, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Paffett, M. T.; Ianakiev, K. D.

    2018-01-01

    Improving the quality of safeguards measurements at Gas Centrifuge Enrichment Plants while reducing the inspection effort is an important objective given the number of existing and new plants that need to be safeguarded. A useful tool in many safeguards approaches is the on-line monitoring of enrichment in process pipes. One requirement of such a monitor is a simple, reliable and precise passive measurement of the 186-keV line from 235U. The other information required is the amount of gas in the pipe, which can be obtained by a transmission or pressure measurement. We describe our research to develop such a passive measurement system. Unfortunately, a complication arises in the interpretation of the gamma measurements, from the contribution of uranium deposits on the wall of the pipe to the 186-keV peak. A multi-detector approach to address this complication is presented where two measurements, one with signal primarily from gas and one with signal primarily from deposits, are performed simultaneously with different detectors and geometries. This allows a correction to be made to the 186-keV peak for the contribution from the deposit. We present the design of the multi-detector system and the results of the experimental calibration of the proof-of-principle prototype built at LANL.

  14. Multi-detector system approach for unattended uranium enrichment monitoring at gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Favalli, A.; Lombardi, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.

    2017-01-01

    Improving the quality of safeguards measurements at Gas Centrifuge Enrichment Plants while reducing the inspection effort is an important objective given the number of existing and new plants that need to be safeguarded. A useful tool in many safeguards approaches is the on-line monitoring of enrichment in process pipes. One requirement of such a monitor is a simple, reliable and precise passive measurement of the 186-keV line from 235 U. The other information required is the amount of gas in the pipe, which can be obtained by a transmission or pressure measurement. Here, we describe our research to develop such a passive measurement system. Unfortunately, a complication arises in the interpretation of the gamma measurements, from the contribution of uranium deposits on the wall of the pipe to the 186-keV peak. A multi-detector approach to address this complication is presented where two measurements, one with signal primarily from gas and one with signal primarily from deposits, are performed simultaneously with different detectors and geometries. This allows a correction to be made to the 186-keV peak for the contribution from the deposit. Finally, we present the design of the multi-detector system and the results of the experimental calibration of the proof-of-principle prototype built at LANL.

  15. Control and monitoring systems for electron beam flue gas treatment technology

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Licki, J.; Mazurekc, J.; Nelskic, L.; Sobolewskic, L.

    2011-01-01

    The reliable and accurate measurements of gas parameters in essential points of industrial plant are necessary for its proper operation and control. Natural flue gases there are only at the inlet. At other points of plant gas parameters are strongly modified by process control system. The principal role of process monitoring system is to provide the Computer System for Monitoring and Control with continuous recording of process parameters. The main goal of control system is to obtain the optimal SO 2 and NO x removal efficiencies by control of amount of spray water at the spray cooler, amount of NH 3 injection to flue gas and adjustment of electron beam current. The structure of the process control system is based on algorithms describing functional dependence of SO 2 and NO x removal efficiencies. The best available techniques should be applied for measurements of flue gases parameters at essential points of installation and for digital control system to assist plant operators in the analysis and optimization of plant operation, including integrated emission control. (author)

  16. Control and monitoring systems for electron beam flue gas treatment technology

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewski, A. G. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Licki, J. [Institute of Atomic Energy, Otwock-Świerk (Poland); Mazurekc, J.; Nelskic, L.; Sobolewskic, L. [Dolna Odra Group, Pomorzany Power Plant, Szczecin (Poland)

    2011-07-01

    The reliable and accurate measurements of gas parameters in essential points of industrial plant are necessary for its proper operation and control. Natural flue gases there are only at the inlet. At other points of plant gas parameters are strongly modified by process control system. The principal role of process monitoring system is to provide the Computer System for Monitoring and Control with continuous recording of process parameters. The main goal of control system is to obtain the optimal SO{sub 2} and NO{sub x} removal efficiencies by control of amount of spray water at the spray cooler, amount of NH{sub 3} injection to flue gas and adjustment of electron beam current. The structure of the process control system is based on algorithms describing functional dependence of SO{sub 2} and NO{sub x} removal efficiencies. The best available techniques should be applied for measurements of flue gases parameters at essential points of installation and for digital control system to assist plant operators in the analysis and optimization of plant operation, including integrated emission control. (author)

  17. Bird interactions with offshore oil and gas platforms: review of impacts and monitoring techniques.

    Science.gov (United States)

    Ronconi, Robert A; Allard, Karel A; Taylor, Philip D

    2015-01-01

    Thousands of oil and gas platforms are currently operating in offshore waters globally, and this industry is expected to expand in coming decades. Although the potential environmental impacts of offshore oil and gas activities are widely recognized, there is limited understanding of their impacts on migratory and resident birds. A literature review identified 24 studies and reports of bird-platform interactions, most being qualitative and half having been peer-reviewed. The most frequently observed effect, for seabirds and landbirds, is attraction and sometimes collisions associated with lights and flares; episodic events have caused the deaths of hundreds or even thousands of birds. Though typically unpredictable, anecdotally, it is known that poor weather, such as fog, precipitation and low cloud cover, can exacerbate the effect of nocturnal attraction to lights, especially when coincidental with bird migrations. Other effects include provision of foraging and roosting opportunities, increased exposure to oil and hazardous environments, increased exposure to predators, or repulsion from feeding sites. Current approaches to monitoring birds at offshore platforms have focused on observer-based methods which can offer species-level bird identification, quantify seasonal patterns of relative abundance and distribution, and document avian mortality events and underlying factors. Observer-based monitoring is time-intensive, limited in spatial and temporal coverage, and suffers without clear protocols and when not conducted by trained, independent observers. These difficulties are exacerbated because deleterious bird-platform interaction is episodic and likely requires the coincidence of multiple factors (e.g., darkness, cloud, fog, rain conditions, occurrence of birds in vicinity). Collectively, these considerations suggest a need to implement supplemental systems for monitoring bird activities around offshore platforms. Instrument-based approaches, such as radar

  18. On-Line Fuel Failure Monitor for Fuel Testing and Monitoring of Gas Cooled Very High Temperature Reactors

    International Nuclear Information System (INIS)

    Hawari, Ayman I.; Bourham, Mohamed A.

    2010-01-01

    Very High Temperature Reactors (VHTR) utilize the TRISO microsphere as the fundamental fuel unit in the core. The TRISO microsphere (∼ 1-mm diameter) is composed of a UO2 kernel surrounded by a porous pyrolytic graphite buffer, an inner pyrolytic graphite layer, a silicon carbide (SiC) coating, and an outer pyrolytic graphite layer. The U-235 enrichment of the fuel is expected to range from 4%-10% (higher enrichments are also being considered). The layer/coating system that surrounds the UO2 kernel acts as the containment and main barrier against the environmental release of radioactivity. To understand better the behavior of this fuel under in-core conditions (e.g., high temperature, intense fast neutron flux, etc.), the US Department of Energy (DOE) is launching a fuel testing program that will take place at the Advanced Test Reactor (ATR) located at Idaho National Laboratory (INL). During this project North Carolina State University (NCSU) researchers will collaborate with INL staff for establishing an optimized system for fuel monitoring for the ATR tests. In addition, it is expected that the developed system and methods will be of general use for fuel failure monitoring in gas cooled VHTRs.

  19. Application of geoelectric methods for man-caused gas deposit mapping and monitoring

    Science.gov (United States)

    Yakymchuk, M. A.; Levashov, S. P.; Korchagin, I. N.; Syniuk, B. B.

    2009-04-01

    anomaly total area made S=20.7 hectares on 07.10.08, and S=19.7 hectares on 13.10.08 and S=10.5 hectares on 08.11.08. The anomaly intensity has decreased, some local extremum has appeared. All this testifies that there is an intensive degassing process of cross-section upper part through producing wells and the drilled degassing wells. Exclusively important feature of the FSPEF-VERS technology is an operationability(!) the of practical problems solving. For an emergency situation on gas field an operationability of technology has crucial importance. For one day of works only the field staff management has received considerable volume of operative information, allowing in quite proved manner to estimate as accident scales and it possible reasons, and so those threats, which this accident can represent for nearby located settlements. So, the imposing of a sketch-map of distribution of a "man-caused" gas deposit on a map of wells location has shown that this deposit does not extend over field border and, hence, does not represent essential threat for nearby settlements. Technology operationability in a whole and practical experience of repeated measurements testifies about possibility of the FSPEF-VERS methods using for operative carrying out of monitoring character survey. Such monitoring survey can be spent on a field after degassing wells drilling to check the process of gas pump-down from a "man-caused" deposit. Geoelectric researches on an emergency site of field on 08.11.08 and the received thus results practically show efficiency and working capacity of the FSPEF-VERS technology in a monitoring mode. The performed experimental works have shown, that process of gas pump-down from a "man-caused" deposit can be traced in time by the FSPEF-VERS technology. It is expedient to locate the additional degassing wells for definitive elimination of accident consequences with taking into account the data of monitoring works by FSPEF-VERS methods. The experiment results testify of

  20. Monitoring system of depressurization valves of migrated gas in annular space of flexible risers

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Luiz A.; Santos, Joilson M.; Carvalho, Antonio L.; Loureiro, Patricia [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2005-07-01

    PETROBRAS Research and Development Center - CENPES developed an automatic system for monitoring pressure of annular space due to permeation of gas in flexible risers to inspect continuously integrity of such lines. To help maintaining physical integrity of flexible risers, two PSV's are installed to end fittings on top of riser, so that operation of any valve grants the maximum admissible gas pressure within the riser annular space, as overpressure might cause damages to external polymeric layer of flexible riser. Due to the fact that there is no mechanism allowing operation to verify correct PSV performance and frequency of valve's closings and openings, we felt to be necessary the development and implement an automatic instrumented system, integrated to platform's automation and control infrastructure. The objective of this instrumentation is to monitor and register pressure of annular space in flexible riser, as well as XV's depressurization frequency. Having such information registered and monitored, can infer some riser structural conditions, anticipating repairs and preventive maintenance. In this paper we present developed system details including instruments required, application, operation of associated screens that are used in the ECOS, with events, alarms and industrial automation services required (Application development and system integration). (author)

  1. Biochemical gas sensor (bio-sniffer) for ultrahigh-sensitive gaseous formaldehyde monitoring.

    Science.gov (United States)

    Kudo, Hiroyuki; Suzuki, Yuki; Gessei, Tomoko; Takahashi, Daishi; Arakawa, Takahiro; Mitsubayashi, Kohji

    2010-10-15

    An ultrahigh-sensitive fiber-optic biochemical gas sensor (bio-sniffer) for continuous monitoring of indoor formaldehyde was constructed and tested. The bio-sniffer measures gaseous formaldehyde as fluorescence of nicotinamide adenine dinucleotide (NADH), which is the product of formaldehyde dehydrogenase (FALDH) reaction. The bio-sniffer device was constructed by attaching a flow cell with a FALDH immobilized membrane onto a fiber-optic NADH measurement system. The NADH measurement system utilizes an ultraviolet-light emitting diode (UV-LED) with peak emission of 335 nm as an excitation light source. The excitation light was introduced to an optical fiber probe, and fluorescence emission of neighboring NADH, which was produced by applying formaldehyde vapor to the FALDH membrane, was concentrically measured with a photomultiplier tube. Assessment of the bio-sniffer was carried out using a standard gas generator. Response, calibration range and selectivity to other chemical substances were investigated. Circulating phosphate buffer, which contained NAD+, available for continuous monitoring of formaldehyde vapor. The calibration range of the bio-sniffer was 2.5 ppb to 10 ppm, which covers the guideline value of the World Health Organization (80 ppb). High selectivity to other gaseous substances due to specific activity of FALDH was also confirmed. Considering its high sensitivity, a possible application of the bio-sniffer is continuous indoor formaldehyde monitoring to provide healthy residential atmosphere. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. Ratiometric Gas Reporting: A Nondisruptive Approach To Monitor Gene Expression in Soils.

    Science.gov (United States)

    Cheng, Hsiao-Ying; Masiello, Caroline A; Del Valle, Ilenne; Gao, Xiaodong; Bennett, George N; Silberg, Jonathan J

    2018-03-16

    Fluorescent proteins are ubiquitous tools that are used to monitor the dynamic functions of natural and synthetic genetic circuits. However, these visual reporters can only be used in transparent settings, a limitation that complicates nondisruptive measurements of gene expression within many matrices, such as soils and sediments. We describe a new ratiometric gas reporting method for nondisruptively monitoring gene expression within hard-to-image environmental matrices. With this approach, C 2 H 4 is continuously synthesized by ethylene forming enzyme to provide information on viable cell number, and CH 3 Br is conditionally synthesized by placing a methyl halide transferase gene under the control of a conditional promoter. We show that ratiometric gas reporting enables the creation of Escherichia coli biosensors that report on acylhomoserine lactone (AHL) autoinducers used for quorum sensing by Gram-negative bacteria. Using these biosensors, we find that an agricultural soil decreases the bioavailable concentration of a long-chain AHL up to 100-fold. We also demonstrate that these biosensors can be used in soil to nondisruptively monitor AHLs synthesized by Rhizobium leguminosarum and degraded by Bacillus thuringiensis. Finally, we show that this new reporting approach can be used in Shewanella oneidensis, a bacterium that lives in sediments.

  3. Physics Simulation Software for Autonomous Propellant Loading and Gas House Autonomous System Monitoring

    Science.gov (United States)

    Regalado Reyes, Bjorn Constant

    2015-01-01

    1. Kennedy Space Center (KSC) is developing a mobile launching system with autonomous propellant loading capabilities for liquid-fueled rockets. An autonomous system will be responsible for monitoring and controlling the storage, loading and transferring of cryogenic propellants. The Physics Simulation Software will reproduce the sensor data seen during the delivery of cryogenic fluids including valve positions, pressures, temperatures and flow rates. The simulator will provide insight into the functionality of the propellant systems and demonstrate the effects of potential faults. This will provide verification of the communications protocols and the autonomous system control. 2. The High Pressure Gas Facility (HPGF) stores and distributes hydrogen, nitrogen, helium and high pressure air. The hydrogen and nitrogen are stored in cryogenic liquid state. The cryogenic fluids pose several hazards to operators and the storage and transfer equipment. Constant monitoring of pressures, temperatures and flow rates are required in order to maintain the safety of personnel and equipment during the handling and storage of these commodities. The Gas House Autonomous System Monitoring software will be responsible for constantly observing and recording sensor data, identifying and predicting faults and relaying hazard and operational information to the operators.

  4. Monitoring of good practices programs and independence for electricity and natural gas system operators. 2010 report

    International Nuclear Information System (INIS)

    2011-01-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 6. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2010. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2010 and audits carried out by the CRE services in these companies in 2010

  5. Monitoring of good practices programs and independence for electricity and natural gas system operators. Report 2012

    International Nuclear Information System (INIS)

    2013-09-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 8. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2012. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2012 and audits carried out by the CRE services in these companies in 2012

  6. Tritium monitoring in the GCFR sweep gas fuel irradiation capsule BG-10

    International Nuclear Information System (INIS)

    Gat, U.; Pruitt, M.E.; Longest, A.W.; Epstein, B.D.

    1980-01-01

    The release of tritium and its transport pathways were studied in a vented, pressure-equalized fuel rod which simulated a fuel rod in a Gas-Cooled Fast Reactor (GCFR). The purpose was to determine the fraction of total tritium production transported via the various pathways and to determine its chemical form (tritiated hydrogen or water). It was concluded that the fuel rod and its effluent venting lines retained low concentrations of HT (or T 2 ) and any HTO (or T 2 O) present. However, the addition of 1% hydrogen to the helium carrier gas quantitatively eluted the tritium from the charcoal trap integral to the fuel rod and from the effluent lines. The chemical composition of the tritium arriving at the monitoring system could be determined by means of converters which convert HT to HTO and vice versa. Ht was the dominant species in the samples measured

  7. Mobile Monitoring of Methane During and After the Aliso Canyon Natural Gas Leak

    Science.gov (United States)

    Polidori, A.; Pikelnaya, O.; Low, J.; Wimmer, R.; Zhou, Q.

    2016-12-01

    The Aliso Canyon gas leak was discovered inside the SoCalGas (SCG) facility on October 23, 2015. This incident represented the worst natural gas leak in the US history, and spurred a number of odor nuisance complaints from local residents. The community of Porter Ranch, located directly south of the SCG Aliso Canyon facility, was the most affected by the leak although complaints have been also reported in other neighboring communities of the San Fernando Valley. Therefore, monitoring of air quality was and remains crucial for measuring the impact of methane emissions from this leak and assessing the well-being of all residents. As the main local air quality agency for this area, South Coast Air Quality Management District (SCAQMD) organized a set of monitoring activities in response to the leak. Since December 21, 2015 SCAQMD has been conducting mobile survey measurements in and around Porter Ranch to characterize methane levels and concentration gradients within the community. For this purpose, a fast-response optical methane analyzer (LI-COR 7700) and a Global Positioning System (GPS) were mounted on top of a hybrid vehicle and driven around Porter Ranch and other surrounding areas. Following the permanent seal of the leaking well on February 18, 2016 mobile measurements have also been expanded to inside the Aliso Canyon SCG facility. During this presentation we will describe the experimental setup designed for mobile methane surveys and the monitoring strategy used for this study. We will discuss the main results of our mobile measurements including long-term methane trends since the end of the leak.

  8. On-line gamma spectroscopy measuring station for cover gas monitoring at KNK II

    International Nuclear Information System (INIS)

    Hoffmann, G.; Letz, K.D.

    1980-02-01

    An automated Ge-γ-spectrometer was developed for cover gas monitoring at KNK II which, by the gamma spectra measured, is to allow the following statements to be made on fuel cladding failure: Type, size, variation with time and subsequent development of the failure. In this report the hardware and software will be explained. Besides, an instruction manual was written for the measuring station, which allows to operate it without detailed knowledge of the manuals for the individual hardware components. (orig.) 891 HP/orig. 892 MKO [de

  9. Expansion of the acceptance program: nitrous oxide scavenging equipment and nitrous oxide trace gas monitoring equipment

    Energy Technology Data Exchange (ETDEWEB)

    1977-10-01

    The Acceptance Program for dental materials and devices and the general guidelines for submission of products have been reported in the Journal (88:615 March 1974). At its April 1977 meeting, the Council included equipment for scavenging and monitoring trace nitrous oxide gas in its Acceptance Program. The Council has established the effective date for classification of products under these two sets of guidelines as one year from the date of publication of this announcement. After that date, classification of a product will be required before promotion or exhibition in Association media.

  10. Monitoring and Control of the Hybrid Laser-Gas Metal-Arc Welding Process

    Energy Technology Data Exchange (ETDEWEB)

    Kunerth, D. C.; McJunkin, T. R.; Nichol, C. I.; Clark, D.; Todorov, E.; Couch, R. D.; Yu, F.

    2013-07-01

    Methods are currently being developed towards a more robust system real time feedback in the high throughput process combining laser welding with gas metal arc welding. A combination of ultrasonic, eddy current, electronic monitoring, and visual techniques are being applied to the welding process. Initial simulation and bench top evaluation of proposed real time techniques on weld samples are presented along with the concepts to apply the techniques concurrently to the weld process. Consideration for the eventual code acceptance of the methods and system are also being researched as a component of this project. The goal is to detect defects or precursors to defects and correct when possible during the weld process.

  11. GULF OF MEXICO SEAFLOOR STABILITY AND GAS HYDRATE MONITORING STATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    J. Robert Woolsey; Thomas M. McGee; Robin C. Buchannon

    2004-11-01

    The gas hydrates research Consortium (HRC), established and administered at the University if Mississippi's Center for Marine Research and Environmental Technology (CMRET) has been active on many fronts in FY 03. Extension of the original contract through March 2004, has allowed completion of many projects that were incomplete at the end of the original project period due, primarily, to severe weather and difficulties in rescheduling test cruises. The primary objective of the Consortium, to design and emplace a remote sea floor station for the monitoring of gas hydrates in the Gulf of Mexico by the year 2005 remains intact. However, the possibility of levering HRC research off of the Joint Industries Program (JIP) became a possibility that has demanded reevaluation of some of the fundamental assumptions of the station format. These provisions are discussed in Appendix A. Landmark achievements of FY03 include: (1) Continuation of Consortium development with new researchers and additional areas of research contribution being incorporated into the project. During this period, NOAA's National Undersea Research Program's (NURP) National Institute for Undersea Science and Technology (NIUST) became a Consortium funding partner, joining DOE and Minerals Management Service (MMS); (2) Very successful annual and semiannual meetings in Oxford Mississippi in February and September, 2003; (3) Collection of piston cores from MC798 in support of the effort to evaluate the site for possible monitoring station installation; (4) Completion of the site evaluation effort including reports of all localities in the northern Gulf of Mexico where hydrates have been documented or are strongly suspected to exist on the sea floor or in the shallow subsurface; (5) Collection and preliminary evaluation of vent gases and core samples of hydrate from sites in Green Canyon and Mississippi Canyon, northern Gulf of Mexico; (6) Monitoring of gas activity on the sea floor, acoustically

  12. Monitoring the evolution and migration of a methane gas plume in an unconfined sandy aquifer using time-lapse GPR and ERT.

    Science.gov (United States)

    Steelman, Colby M; Klazinga, Dylan R; Cahill, Aaron G; Endres, Anthony L; Parker, Beth L

    2017-10-01

    Fugitive methane (CH 4 ) leakage associated with conventional and unconventional petroleum development (e.g., shale gas) may pose significant risks to shallow groundwater. While the potential threat of stray (CH 4 ) gas in aquifers has been acknowledged, few studies have examined the nature of its migration and fate in a shallow groundwater flow system. This study examines the geophysical responses observed from surface during a 72day field-scale simulated CH 4 leak in an unconfined sandy aquifer at Canadian Forces Base Borden, Canada, to better understand the transient behaviour of fugitive CH 4 gas in the subsurface. Time-lapse ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) were used to monitor the distribution and migration of the gas-phase and assess any impacts to groundwater hydrochemistry. Geophysical measurements captured the transient formation of a CH 4 gas plume emanating from the injector, which was accompanied by an increase in total dissolved gas pressure (P TDG ). Subsequent reductions in P TDG were accompanied by reduced bulk resistivity around the injector along with an increase in the GPR reflectivity along horizontal bedding reflectors farther downgradient. Repeat temporal GPR reflection profiling identified three events with major peaks in reflectivity, interpreted to represent episodic lateral CH 4 gas release events into the aquifer. Here, a gradual increase in P TDG near the injector caused a sudden lateral breakthrough of gas in the direction of groundwater flow, causing free-phase CH 4 to migrate much farther than anticipated based on groundwater advection. CH 4 accumulated along subtle permeability boundaries demarcated by grain-scale bedding within the aquifer characteristic of numerous Borden-aquifer multi-phase flow experiments. Diminishing reflectivity over a period of days to weeks suggests buoyancy-driven migration to the vadose zone and/or CH 4 dissolution into groundwater. Lateral and vertical CH 4

  13. Calibration of low-cost gas sensors for an urban air quality monitoring network

    Science.gov (United States)

    Scott, A.; Kelley, C.; He, C.; Ghugare, P.; Lehman, A.; Benish, S.; Stratton, P.; Dickerson, R. R.; Zuidema, C.; Azdoud, Y.; Ren, X.

    2017-12-01

    In a warming world, environmental pollution may be exacerbated by anthropogenic activities, such as climate change and the urban heat island effect, as well as natural phenomena such as heat waves. However, monitoring air pollution at federal reference standards (approximately 1 part per billion or ppb for ambient ozone) is cost-prohibitive in heterogeneous urban areas as many expensive devices are required to fully capture a region's geo-spatial variability. Innovation in low-cost sensors provide a potential solution, yet technical challenges remain to overcome possible imprecision in the data. We present the calibrations of ozone and nitrous dioxide from a low-cost air quality monitoring device designed for the Baltimore Open Air Project. The sensors used in this study are commercially available thin film electrochemical sensors from SPEC Sensor, which are amperometric, meaning they generate current proportional to volumetric fraction of gas. The results of sensor calibrations in the laboratory and field are presented.

  14. From the Lab to the real world : sources of error in UF6 gas enrichment monitoring

    International Nuclear Information System (INIS)

    Lombardi, Marcie L.

    2012-01-01

    Safeguarding uranium enrichment facilities is a serious concern for the International Atomic Energy Agency (IAEA). Safeguards methods have changed over the years, most recently switching to an improved safeguards model that calls for new technologies to help keep up with the increasing size and complexity of today's gas centrifuge enrichment plants (GCEPs). One of the primary goals of the IAEA is to detect the production of uranium at levels greater than those an enrichment facility may have declared. In order to accomplish this goal, new enrichment monitors need to be as accurate as possible. This dissertation will look at the Advanced Enrichment Monitor (AEM), a new enrichment monitor designed at Los Alamos National Laboratory. Specifically explored are various factors that could potentially contribute to errors in a final enrichment determination delivered by the AEM. There are many factors that can cause errors in the determination of uranium hexafluoride (UF 6 ) gas enrichment, especially during the period when the enrichment is being measured in an operating GCEP. To measure enrichment using the AEM, a passive 186-keV (kiloelectronvolt) measurement is used to determine the 235 U content in the gas, and a transmission measurement or a gas pressure reading is used to determine the total uranium content. A transmission spectrum is generated using an x-ray tube and a 'notch' filter. In this dissertation, changes that could occur in the detection efficiency and the transmission errors that could result from variations in pipe-wall thickness will be explored. Additional factors that could contribute to errors in enrichment measurement will also be examined, including changes in the gas pressure, ambient and UF 6 temperature, instrumental errors, and the effects of uranium deposits on the inside of the pipe walls will be considered. The sensitivity of the enrichment calculation to these various parameters will then be evaluated. Previously, UF 6 gas enrichment

  15. Monitoring and modeling wetland chloride concentrations in relationship to oil and gas development

    Science.gov (United States)

    Post van der Burg, Max; Tangen, Brian A.

    2015-01-01

    Extraction of oil and gas via unconventional methods is becoming an important aspect of energy production worldwide. Studying the effects of this development in countries where these technologies are being widely used may provide other countries, where development may be proposed, with some insight in terms of concerns associated with development. A fairly recent expansion of unconventional oil and gas development in North America provides such an opportunity. Rapid increases in energy development in North America have caught the attention of managers and scientists as a potential stressor for wildlife and their habitats. Of particular concern in the Northern Great Plains of the U.S. is the potential for chloride-rich produced water associated with unconventional oil and gas development to alter the water chemistry of wetlands. We describe a landscape scale modeling approach designed to examine the relationship between potential chloride contamination in wetlands and patterns of oil and gas development. We used a spatial Bayesian hierarchical modeling approach to assess multiple models explaining chloride concentrations in wetlands. These models included effects related to oil and gas wells (e.g. age of wells, number of wells) and surficial geology (e.g. glacial till, outwash). We found that the model containing the number of wells and the surficial geology surrounding a wetland best explained variation in chloride concentrations. Our spatial predictions showed regions of localized high chloride concentrations. Given the spatiotemporal variability of regional wetland water chemistry, we do not regard our results as predictions of contamination, but rather as a way to identify locations that may require more intensive sampling or further investigation. We suggest that an approach like the one outlined here could easily be extended to more of an adaptive monitoring approach to answer questions about chloride contamination risk that are of interest to managers.

  16. Dissolved Oxygen Sensor in Animal-Borne Instruments: An Innovation for Monitoring the Health of Oceans and Investigating the Functioning of Marine Ecosystems.

    Science.gov (United States)

    Bailleul, Frederic; Vacquie-Garcia, Jade; Guinet, Christophe

    2015-01-01

    The current decline in dissolved oxygen concentration within the oceans is a sensitive indicator of the effect of climate change on marine environment. However the impact of its declining on marine life and ecosystems' health is still quite unclear because of the difficulty in obtaining in situ data, especially in remote areas, like the Southern Ocean (SO). Southern elephant seals (Mirounga leonina) proved to be a relevant alternative to the traditional oceanographic platforms to measure physical and biogeochemical structure of oceanic regions rarely observed. In this study, we use a new stage of development in biologging technology to draw a picture of dissolved oxygen concentration in the SO. We present the first results obtained from a dissolved oxygen sensor added to Argos CTD-SRDL tags and deployed on 5 female elephant seals at Kerguelen. From October 2010 and October 2011, 742 oxygen profiles associated with temperature and salinity measurements were recorded. Whether a part of the data must be considered cautiously, especially because of offsets and temporal drifts of the sensors, the range of values recorded was consistent with a concomitant survey conducted from a research vessel (Keops-2 project). Once again, elephant seals reinforced the relationship between marine ecology and oceanography, delivering essential information about the water masses properties and the biological status of the Southern Ocean. But more than the presentation of a new stage of development in animal-borne instrumentation, this pilot study opens a new field of investigation in marine ecology and could be enlarged in a near future to other key marine predators, especially large fish species like swordfish, tuna or sharks, for which dissolved oxygen is expected to play a crucial role in distribution and behaviour.

  17. Dissolved Oxygen Sensor in Animal-Borne Instruments: An Innovation for Monitoring the Health of Oceans and Investigating the Functioning of Marine Ecosystems.

    Directory of Open Access Journals (Sweden)

    Frederic Bailleul

    Full Text Available The current decline in dissolved oxygen concentration within the oceans is a sensitive indicator of the effect of climate change on marine environment. However the impact of its declining on marine life and ecosystems' health is still quite unclear because of the difficulty in obtaining in situ data, especially in remote areas, like the Southern Ocean (SO. Southern elephant seals (Mirounga leonina proved to be a relevant alternative to the traditional oceanographic platforms to measure physical and biogeochemical structure of oceanic regions rarely observed. In this study, we use a new stage of development in biologging technology to draw a picture of dissolved oxygen concentration in the SO. We present the first results obtained from a dissolved oxygen sensor added to Argos CTD-SRDL tags and deployed on 5 female elephant seals at Kerguelen. From October 2010 and October 2011, 742 oxygen profiles associated with temperature and salinity measurements were recorded. Whether a part of the data must be considered cautiously, especially because of offsets and temporal drifts of the sensors, the range of values recorded was consistent with a concomitant survey conducted from a research vessel (Keops-2 project. Once again, elephant seals reinforced the relationship between marine ecology and oceanography, delivering essential information about the water masses properties and the biological status of the Southern Ocean. But more than the presentation of a new stage of development in animal-borne instrumentation, this pilot study opens a new field of investigation in marine ecology and could be enlarged in a near future to other key marine predators, especially large fish species like swordfish, tuna or sharks, for which dissolved oxygen is expected to play a crucial role in distribution and behaviour.

  18. Monitoring internal corrosion in natural gas pipelines; Monitoracao da corrosao interna em gasodutos

    Energy Technology Data Exchange (ETDEWEB)

    Nobrega, Ana C.V.; Silva, Djalma R.; Pimenta, Gutemberg S. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Barbosa, Andrea F.F. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2003-07-01

    For susceptibilities to the corrosion of the pipelines and equipment made in carbon steel and used by the natural gas, it makes be necessary to identify the acting corrosive agents and monitoring them along time, controlling failures for internal corrosion. Also, of that process it origins the black powder (solid particles) that can not commit the structural integrity of the equipment, but it can also bring the company other implications very serious, like quality of the sold product, as well as stops due to blockages and wastes for erosion of the equipment. The monitoring methodology and control of the corrosion in field consisted of the use of corrosion test equipment, chemical characterization of samples of black powder and liquids and analysis of the operational data of processes and plants. Like this, it was identified for the gas pipeline in analysis the most responsible parameters for the corrosive action of the fluid, establishing a controlling methodology and operational actions to maintain the corrosion rates at safe levels and structural warranty of the same. (author)

  19. Assessment of a continuous blood gas monitoring system in animals during circulatory stress

    Directory of Open Access Journals (Sweden)

    Renzulli Attilio

    2011-01-01

    Full Text Available Abstract Background The study was aimed to determine the measurement accuracy of The CDI™ blood parameter monitoring system 500 (Terumo Cardiovascular Systems Corporation, Ann Arbor MI in the real-time continuous measurement of arterial blood gases under different cardiocirculatory stress conditions Methods Inotropic stimulation (Dobutamine 2.5 and 5 μg/kg/min, vasoconstriction (Arginine-vasopressin 4, 8 and 16 IU/h, hemorrhage (-10%, -20%, -35%, and -50% of the theoretical volemia, and volume resuscitation were induced in ten swine (57.4 ± 10.7 Kg.Intermittent blood gas assessments were carried out using a routine gas analyzer at any experimental phase and compared with values obtained at the same time settings during continuous monitoring with CDI™ 500 system. The Bland-Altman analysis was employed. Results Bias and precision for pO2 were - 0.06 kPa and 0.22 kPa, respectively (r2 = 0.96; pCO2 - 0.02 kPa and 0.15 kPa, respectively; pH -0.001 and 0.01 units, respectively ( r2 = 0.96. The analysis showed very good agreement for SO2 (bias 0.04,precision 0.33, r2 = 0.95, Base excess (bias 0.04,precision 0.28, r2 = 0.98, HCO3 (bias 0.05,precision 0.62, r2 = 0.92,hemoglobin (bias 0.02,precision 0.23, r2 = 0.96 and K+ (bias 0.02, precision 0.27, r2 = 0.93. The sensor was reliable throughout the experiment during hemodynamic variations. Conclusions Continuous blood gas analysis with the CDI™ 500 system was reliable and it might represent a new useful tool to accurately and timely monitor gas exchange in critically ill patients. Nonetheless, our findings need to be confirmed by larger studies to prove its reliability in the clinical setting.

  20. Commissioning of the KATRIN Raman system for monitoring of the WGTS gas composition

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Sebastian; Bornschein, Beate; James, Timothy M.; Off, Andreas; Rupp, Simone; Seitz-Moskaliuk, Hendrik; Sturm, Michael; Wecker, Matthias [Karlsruhe Institute of Technology (Germany); Schloesser, Magnus [Universidad Complutense de Madrid (Spain); Karlsruhe Institute of Technology (Germany); Telle, Helmut H. [Universidad Complutense de Madrid (Spain)

    2015-07-01

    The Karlsruhe Tritium Neutrino (KATRIN) Experiment aims at determining the neutrino mass by the investigation of the endpoint energy-region of the tritium β-spectrum. Tritium in its molecular form ({sup 3}H{sub 2}) is injected into the Windowless Gaseous Tritium Source (WGTS) of KATRIN, and thus molecular effects, e.g. ro-vibrational excitations levels, have to be considered in the neutrino mass analysis in order to reach the design sensitivity of 200 meV/c{sup 2} (90% C.L.). As the source gas also contains impurities of the other hydrogen isotopes protium and deuterium - giving rise to different molecular excitation levels - continuous and precise monitoring of the source gas composition is required. Raman spectroscopy is the method of choice for this task as it is an inline and non-contact analysis method. In this talk, results from the recently performed commissioning phase of the KATRIN Raman system are presented: over the course of more than 50 days, consecutive Raman spectra (recorded with acquisition times of 60 s) of circulating tritium gas were acquired and analysed in real-time. In addition, valuable information on the system performance during long-term operation was gained.

  1. Radioactive contamination monitoring device for off-gas in ventilation system

    International Nuclear Information System (INIS)

    Osaki, Masahiko; Watabe, Atsushi; Kaneko, Itaru; Kubokoya, Takashi.

    1990-01-01

    In a conventional method of detecting leakage for primary coolants, radioactive iodine in off-gases was detected while going up the off-gas system. As an event resulting in abnormality to radioactive rare gas level, leakage of water, leakage in cleanup system-recycling system, leakage in main steams and leakage from wastes processing system are considered. An off-gas system to be measured is selectively sampled by a sample changer in order to measure radioactive rare gases in the off-gases, and sample gases are introduced to detect radioactivity. Detection signals are received for analysis and quantitative determination, the result of the analysis is diagnosed and the presence or absence of abnormality in an object to be measured is determined. Subsequently, an abnormality alarm and the result of the analysis are outputted. Since the radioactive rare gases are chemically inactive, they are neither combined with other materials nor deposited to wall surfaces. Abnormality can be easily detected by always monitoring a composition pattern and a radioactivity level. (N.H.)

  2. Stable carbon isotopic composition of gasolines determined by isotope ratio monitoring gas chromatography mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Smallwood, B.J.; Philp, R.P.; Allen, J.D. [University of Oklahoma, Norman, OK (United States). School of Geology and Geophysics

    2002-07-01

    A large number of underground gasoline storage facilities in the United States continuously leak gasoline into the subsurface, which makes gasoline a major groundwater contaminant. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) are used currently to characterize contaminated groundwater and soils. Correlations of contaminants with suspected source(s) are extremely difficult by these techniques because many gasolines have similar hydrocarbon distributions. The present study applied the technique of isotope ratio monitoring gas chromatography-mass spectrometry (irmGC-MS) to 19 gasoline samples from different areas of the USA. This allows a much better correlation of gasoline contaminants to source. Data obtained indicate a wide range of {sup {delta}}{sup 13}C values for 16 ubiquitous compounds in the gasolines. The majority of samples could be distinguished from each other on the basis of {sup {delta}}{sup 13}C hydrocarbon composition. The oxygenated additive methyl tertiary butyl ether (MTBE) was present in ten of the gasolines analyzed, and had a relatively narrow range of {sup {delta}}{sup 13}C values (-30.4 to -28.3 per mille). Preliminary investigations were also made to determine the extent of carbon isotopic fractionation after simple water washing and evaporation experiments. Results indicate that the majority of compounds did not undergo significant carbon isotopic fractionation as a result of these processes. (author)

  3. Laser-Based and Ultra-Portable Gas Sensor for Indoor and Outdoor Formaldehyde (HCHO) Monitoring

    Science.gov (United States)

    Shutter, J. D.; Allen, N.; Paul, J.; Thiebaud, J.; So, S.; Scherer, J. J.; Keutsch, F. N.

    2017-12-01

    While used as a key tracer of oxidative chemistry in the atmosphere, formaldehyde (HCHO) is also a known human carcinogen and is listed and regulated by the United States EPA as a hazardous air pollutant. Combustion processes and photochemical oxidation of volatile organic compounds (VOCs) are the major outdoor sources of HCHO, and building materials and household products are ubiquitous sources of indoor HCHO. Due to the ease with which humans can be exposed to HCHO, it is imperative to monitor levels of both indoor and outdoor HCHO exposure in both short and long-term studies.High-quality direct and indirect methods of quantifying HCHO mixing ratios exist, but instrument size and user-friendliness can make them cumbersome or impractical for certain types of indoor and long-term outdoor measurements. In this study, we present urban HCHO measurements by using a new, commercially-available, ppbv-level accurate HCHO gas sensor (Aeris Technologies' MIRA Pico VOC Laser-Based Gas Analyzer) that is highly portable (29 cm x 20 cm x 10 cm), lightweight (3 kg), easy-to-use, and has low power (15 W) consumption. Using an ultra-compact multipass cell, an absorption path length of 13 m is achieved, resulting in a sensor capable of achieving ppbv/s sensitivity levels with no significant spectral interferences.To demonstrate the utility of the gas sensor for emissions measurements, a GPS was attached to the sensor's housing in order to map mobile HCHO measurements in real-time around the Boston, Massachusetts, metro area. Furthermore, the sensor was placed in residential and industrial environments to show its usefulness for indoor and outdoor pollution measurements. Lastly, we show the feasibility of using the HCHO sensor (or a network of them) in long-term monitoring stations for hazardous air pollutants.

  4. Metal-modified and vertically aligned carbon nanotube sensors array for landfill gas monitoring applications.

    Science.gov (United States)

    Penza, M; Rossi, R; Alvisi, M; Serra, E

    2010-03-12

    Vertically aligned carbon nanotube (CNT) layers were synthesized on Fe-coated low-cost alumina substrates using radio-frequency plasma enhanced chemical vapour deposition (RF-PECVD) technology. A miniaturized CNT-based gas sensor array was developed for monitoring landfill gas (LFG) at a temperature of 150 degrees C. The sensor array was composed of 4 sensing elements with unmodified CNT, and CNT loaded with 5 nm nominally thick sputtered nanoclusters of platinum (Pt), ruthenium (Ru) and silver (Ag). Chemical analysis of multicomponent gas mixtures constituted of CO(2), CH(4), H(2), NH(3), CO and NO(2) has been performed by the array sensor responses and pattern recognition based on principal component analysis (PCA). The PCA results demonstrate that the metal-decorated and vertically aligned CNT sensor array is able to discriminate the NO(2) presence in the multicomponent mixture LFG. The NO(2) gas detection in the mixture LFG was proved to be very sensitive, e.g.: the CNT:Ru sensor shows a relative change in the resistance of 1.50% and 0.55% for NO(2) concentrations of 3.3 ppm and 330 ppb dispersed in the LFG, respectively, with a wide NO(2) gas concentration range measured from 0.33 to 3.3 ppm, at the sensor temperature of 150 degrees C. The morphology and structure of the CNT networks have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. A forest-like nanostructure of vertically aligned CNT bundles in the multi-walled form appeared with a height of about 10 microm and a single-tube diameter varying in the range of 5-35 nm. The intensity ratio of the Raman spectroscopy D-peak and G-peak indicates the presence of disorder and defects in the CNT networks. The size of the metal (Pt, Ru, Ag) nanoclusters decorating the CNT top surface varies in the range of 5-50 nm. Functional characterization based on electrical charge transfer sensing mechanisms in the metal-modified CNT-chemoresistor array

  5. Breath acetone monitoring by portable Si:WO3 gas sensors

    Science.gov (United States)

    Righettoni, Marco; Tricoli, Antonio; Gass, Samuel; Schmid, Alex; Amann, Anton; Pratsinis, Sotiris E.

    2013-01-01

    Breath analysis has the potential for early stage detection and monitoring of illnesses to drastically reduce the corresponding medical diagnostic costs and improve the quality of life of patients suffering from chronic illnesses. In particular, the detection of acetone in the human breath is promising for non-invasive diagnosis and painless monitoring of diabetes (no finger pricking). Here, a portable acetone sensor consisting of flame-deposited and in situ annealed, Si-doped epsilon-WO3 nanostructured films was developed. The chamber volume was miniaturized while reaction-limited and transport-limited gas flow rates were identified and sensing temperatures were optimized resulting in a low detection limit of acetone (~20 ppb) with short response (10–15 s) and recovery times (35–70 s). Furthermore, the sensor signal (response) was robust against variations of the exhaled breath flow rate facilitating application of these sensors at realistic relative humidities (80–90%) as in the human breath. The acetone content in the breath of test persons was monitored continuously and compared to that of state-of-the-art proton transfer reaction mass spectrometry (PTR-MS). Such portable devices can accurately track breath acetone concentration to become an alternative to more elaborate breath analysis techniques. PMID:22790702

  6. An X-ray beam position monitor based on the photoluminescence of helium gas

    Science.gov (United States)

    Revesz, Peter; White, Jeffrey A.

    2005-03-01

    A new method for white beam position monitoring for both bend magnet and wiggler synchrotron X-ray radiation has been developed. This method utilizes visible light luminescence generated as a result of ionization by the intense X-ray flux. In video beam position monitors (VBPMs), the luminescence of helium gas at atmospheric pressure is observed through a view port using a CCD camera next to the beam line. The beam position, profile, integrated intensity and FWHM are calculated from the distribution of luminescence intensity in each captured image by custom software. Misalignment of upstream apertures changes the image profile making VBPMs helpful for initial alignment of upstream beam line components. VBPMs can thus provide more information about the X-ray beam than most beam position monitors (BPMs). A beam position calibration procedure, employing a tilted plane-parallel glass plate placed in front of the camera lens, has also been developed. The accuracy of the VBPM system was measured during a bench-top experiment to be better than 1 μm. The He-luminescence-based VBPM system has been operative on three CHESS beam lines (F hard-bend and wiggler, A-line wiggler and G-line wiggler) for about a year. The beam positions are converted to analog voltages and used as feedback signals for beam stabilization. In our paper we discuss details of VBPM construction and describe further results of its performance.

  7. Radon gas in oil and natural gas production facilities

    International Nuclear Information System (INIS)

    Chandler, W.P.

    1994-01-01

    Radon gas is a naturally occurring radionuclide that can be found in some oil and natural gas production facilities, either as a contaminant in a natural gas stream or derived from Radium dissolved in formation waters. The gas itself is not normally a health hazard, but it's decay products, which can be concentrated by plate-out or deposition as a scale in process equipment, can be a health hazard for maintenance personnel. To evaluate possible health hazards, it is necessary to monitor for naturally occurring radioactive materials (NORM) in the gas stream and in the formation water. If Radon and/or Radium is found, a monitoring programme should be initiated to comply with National or State requirements. In some instances, it has been found necessary to dispose of silt and scale materials as low level radioactive waste. 8 refs

  8. Unique Dispersal of the Changjiang-Diluted Water Plume in the East China Sea Revealed from Satellite Monitoring of Colored Dissolved Organic Matter (CDOM)

    OpenAIRE

    Hiroaki Sasaki; Yasushi Gomi; Takamasa Asai; Masashi Shibata; Yoko Kiyomoto; Kazumaro Okamura; Kou Nishiuchi; Toru Hasegawa; Haruya Yamada

    2014-01-01

    The optical properties of colored dissolved organic matter (CDOM) in the Changjiang (Yangtze River) plume water were investigated during the summer of 2009 and 2010. The absorption coefficient of CDOM at 325 nm (aCDOM) increased inversely with decreasing sea-surface salinity (SSS), implying that aCDOM can be used as a natural tracer of Changjiang-diluted water (CDW). This aCDOM vs. SSS relationship, however, differed between 2009 and 2010. For mapping the CDW plume, the aCDOM was retrieved fr...

  9. Groundwater electrical conductivity and soil radon gas monitoring for earthquake precursory studies in Koyna, India

    International Nuclear Information System (INIS)

    Reddy, D.V.; Nagabhushanam, P.

    2011-01-01

    Research highlights: → It is the first hydrochemical precursory study in the Koyna region, India. → Discrete conductivity measurements indicated progressive increase for 4 years. → Strong precursory EC change observed 40 h before the M 5.1 earthquake. → Precursory increase of soil Rn gas 20 days earlier than earthquakes M 4.7 and 5.1. → On-line monitoring of these parameters may help in earthquake forecast. - Abstract: Hourly monitoring of electrical conductivity (EC) of groundwater along with groundwater levels in the 210 m deep boreholes (specially drilled for pore pressure/earthquake studies) and soil Rn gas at 60 cm below ground level in real time, in the Koyna-Warna region (characterized by basaltic rocks, >1500 m thick, and dotted with several sets of fault systems), western India, provided strong precursory signatures in response to two earthquakes (M 4.7 on 14/11/09, and M 5.1 on 12/12/09) that occurred in the study region. The EC measured in Govare well water showed precursory perturbations about 40 h prior to the M 5.1 earthquake and continued further for about 20 h after the earthquake. In response to the M 4.7 earthquake, there were EC perturbations 8 days after the earthquake. In another well (Koyna) which is located 4 km north of Govare well, no precursory signatures were found for the M 4.7 earthquake, while for M 5.1 earthquake, post-seismic precursors were found 18 days after the earthquake. Increased porosity and reduced pressure head accompanied by mixing of a freshwater component from the top zone due to earthquakes are the suggested mechanisms responsible for the observed anomalies in EC. Another parameter, soil Rn gas showed relatively proportional strength signals corresponding to these two earthquakes. In both the cases, the pre-seismic increase in Rn concentration started about 20 days in advance. The co-seismic drop in Rn levels was less by 30% from its peak value for the M 4.7 earthquake and 50% for the M 5.1 earthquake. The Rn

  10. An Integrated Architecture for On-Board Aircraft Engine Performance Trend Monitoring and Gas Path Fault Diagnostics

    Science.gov (United States)

    Simon, Donald L.

    2010-01-01

    Aircraft engine performance trend monitoring and gas path fault diagnostics are closely related technologies that assist operators in managing the health of their gas turbine engine assets. Trend monitoring is the process of monitoring the gradual performance change that an aircraft engine will naturally incur over time due to turbomachinery deterioration, while gas path diagnostics is the process of detecting and isolating the occurrence of any faults impacting engine flow-path performance. Today, performance trend monitoring and gas path fault diagnostic functions are performed by a combination of on-board and off-board strategies. On-board engine control computers contain logic that monitors for anomalous engine operation in real-time. Off-board ground stations are used to conduct fleet-wide engine trend monitoring and fault diagnostics based on data collected from each engine each flight. Continuing advances in avionics are enabling the migration of portions of the ground-based functionality on-board, giving rise to more sophisticated on-board engine health management capabilities. This paper reviews the conventional engine performance trend monitoring and gas path fault diagnostic architecture commonly applied today, and presents a proposed enhanced on-board architecture for future applications. The enhanced architecture gains real-time access to an expanded quantity of engine parameters, and provides advanced on-board model-based estimation capabilities. The benefits of the enhanced architecture include the real-time continuous monitoring of engine health, the early diagnosis of fault conditions, and the estimation of unmeasured engine performance parameters. A future vision to advance the enhanced architecture is also presented and discussed

  11. Monitoring of gas generation during the charge/discharge regime of miners' headlamps

    International Nuclear Information System (INIS)

    Szanto, Zs.; Molnar, M.; Palcsu, L.; Futo, I.; Rinyu, L.; Svingor, E.

    2004-01-01

    chemistry which indicate charge completion are temperature, voltage and internal cell pressure. As a cell nears full charge, the voltage of the cell, its temperature and pressure all will rise. Full charge detection followed by discharge was achieved under laboratory conditions by monitoring the battery voltage, current and pressure build up terminating the charge when a certain signature occurs (the initially set voltage was reached). Sampling (1 cm 3 of headspace gas) was made at regular intervals and the qualitative and quantitative analysis of gases of the battery was made using a QMS (OMNISTAR, Balzers Instruments). Monitoring of gas generation was made during 16 and 72 hours charge periods followed by 12-13 hours discharge periods. The results showed a constant increase in pressure (up to 2 bars) into the checked cells during the charge period, the generated gases being the following: CH 4 , H 2 and O 2 . The voltage of the three cells increased to 4.40 V while the charge current dropped from 1 A to 0.5 A. During discharge a decrease of the cell voltage was observed a sharp drop being recorded (from 3.0 V to 2.85 V) after 12-13 hours. The excess oxygen generated during the charge period reaching the active sites on the negative plate was recombined from the gaseous state forming hydroxyl ions, so its concentration decreased in the headspace gas. The study showed an increase of up to 19% of H2 into the cells during the 72 hours charge period and up to 15% of H2 into the space between the battery and its outside polycarbonate case, which is not acceptable for underground mining activities. (author)

  12. Fission product monitoring of TRISO coated fuel for the advanced gas reactor-1 experiment

    International Nuclear Information System (INIS)

    Scates, Dawn M.; Hartwell, John K.; Walter, John B.; Drigert, Mark W.; Harp, Jason M.

    2010-01-01

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

  13. Characterisation of dissolved organic compounds in hydrothermal fluids by stir bar sorptive extraction - gas chomatography - mass spectrometry. Case study: the Rainbow field (36°N, Mid-Atlantic Ridge

    Directory of Open Access Journals (Sweden)

    Konn Cecile

    2012-11-01

    Full Text Available Abstract The analysis of the dissolved organic fraction of hydrothermal fluids has been considered a real challenge due to sampling difficulties, complexity of the matrix, numerous interferences and the assumed ppb concentration levels. The present study shows, in a qualitative approach, that Stir Bar Sorptive Extraction (SBSE followed by Thermal Desorption – Gas Chromatography – Mass Spectrometry (TD-GC-MS is suitable for extraction of small sample volumes and detection of a wide range of volatile and semivolatile organic compounds dissolved in hydrothermal fluids. In a case study, the technique was successfully applied to fluids from the Rainbow ultramafic-hosted hydrothermal field located at 36°14’N on the Mid-Atlantic Ridge (MAR. We show that n-alkanes, mono- and poly- aromatic hydrocarbons as well as fatty acids can be easily identified and their retention times determined. Our results demonstrate the excellent repeatability of the method as well as the possibility of storing stir bars for at least three years without significant changes in the composition of the recovered organic matter. A preliminary comparative investigation of the organic composition of the Rainbow fluids showed the great potential of the method to be used for assessing intrafield variations and carrying out time series studies. All together our results demonstrate that SBSE-TD-GC-MS analyses of hydrothermal fluids will make important contributions to the understanding of geochemical processes, geomicrobiological interactions and formation of mineral deposits.

  14. The Potential Applications of Real-Time Monitoring of Water Quality in a Large Shallow Lake (Lake Taihu, China) Using a Chromophoric Dissolved Organic Matter Fluorescence Sensor

    Science.gov (United States)

    Niu, Cheng; Zhang, Yunlin; Zhou, Yongqiang; Shi, Kun; Liu, Xiaohan; Qin, Boqiang

    2014-01-01

    This study presents results from field surveys performed over various seasons in a large, eutrophic, shallow lake (Lake Taihu, China) using an in situ chromophoric dissolved organic matter (CDOM) fluorescence sensor as a surrogate for other water quality parameters. These measurements identified highly significant empirical relationships between CDOM concentration measured using the in situ fluorescence sensor and CDOM absorption, fluorescence, dissolved organic carbon (DOC), chemical oxygen demand (COD) and total phosphorus (TP) concentrations. CDOM concentration expressed in quinine sulfate equivalent units, was highly correlated with the CDOM absorption coefficient (r2 = 0.80, p CDOM concentration measured using the in situ fluorescence sensor could act as a substitute for the CDOM absorption coefficient and fluorescence measured in the laboratory. Similarly, CDOM concentration was highly correlated with DOC concentration (r2 = 0.68, p CDOM fluorescence sensor measurements could be a proxy for DOC concentration. In addition, significant positive correlations were found between laboratory CDOM absorption coefficients and COD (r2 = 0.83, p CDOM fluorescence sensor. PMID:24984060

  15. The potential applications of real-time monitoring of water quality in a large shallow lake (Lake Taihu, China) using a chromophoric dissolved organic matter fluorescence sensor.

    Science.gov (United States)

    Niu, Cheng; Zhang, Yunlin; Zhou, Yongqiang; Shi, Kun; Liu, Xiaohan; Qin, Boqiang

    2014-06-30

    This study presents results from field surveys performed over various seasons in a large, eutrophic, shallow lake (Lake Taihu, China) using an in situ chromophoric dissolved organic matter (CDOM) fluorescence sensor as a surrogate for other water quality parameters. These measurements identified highly significant empirical relationships between CDOM concentration measured using the in situ fluorescence sensor and CDOM absorption, fluorescence, dissolved organic carbon (DOC), chemical oxygen demand (COD) and total phosphorus (TP) concentrations. CDOM concentration expressed in quinine sulfate equivalent units, was highly correlated with the CDOM absorption coefficient (r(2) = 0.80, p CDOM concentration measured using the in situ fluorescence sensor could act as a substitute for the CDOM absorption coefficient and fluorescence measured in the laboratory. Similarly, CDOM concentration was highly correlated with DOC concentration (r(2) = 0.68, p CDOM fluorescence sensor measurements could be a proxy for DOC concentration. In addition, significant positive correlations were found between laboratory CDOM absorption coefficients and COD (r(2) = 0.83, p CDOM fluorescence sensor.

  16. Tracing Acetylene Dissolved in Transformer Oil by Tunable Diode Laser Absorption Spectrum.

    Science.gov (United States)

    Ma, Guo-Ming; Zhao, Shu-Jing; Jiang, Jun; Song, Hong-Tu; Li, Cheng-Rong; Luo, Ying-Ting; Wu, Hao

    2017-11-02

    Dissolved gas analysis (DGA) is widely used in monitoring and diagnosing of power transformer, since the insulation material in the power transformer decomposes gases under abnormal operation condition. Among the gases, acetylene, as a symbol of low energy spark discharge and high energy electrical faults (arc discharge) of power transformer, is an important monitoring parameter. The current gas detection method used by the online DGA equipment suffers from problems such as cross sensitivity, electromagnetic compatibility and reliability. In this paper, an optical gas detection system based on TDLAS technology is proposed to detect acetylene dissolved in transformer oil. We selected a 1530.370 nm laser in the near infrared wavelength range to correspond to the absorption peak of acetylene, while using the wavelength modulation strategy and Herriott cell to improve the detection precision. Results show that the limit of detection reaches 0.49 ppm. The detection system responds quickly to changes of gas concentration and is easily to maintenance while has no electromagnetic interference, cross-sensitivity, or carrier gas. In addition, a complete detection process of the system takes only 8 minutes, implying a practical prospect of online monitoring technology.

  17. Modifying the dissolved-in-water type natural gas field simulation model based on the distribution of estimated Young's modulus for the Kujukuri region, Japan

    Directory of Open Access Journals (Sweden)

    T. Nakagawa

    2015-11-01

    Full Text Available A simulation model, which covers the part of Southern-Kanto natural gas field in Chiba prefecture, was developed to perform studies and make predictions of land subsidence. However, because large differences between simulated and measured subsidence occurred in the northern modeled area of the gas field, the model was modified with an estimated Young's modulus distribution. This distribution was estimated by the yield value distribution and the correlation of yield value with Young's modulus. Consequently, the simulated subsidence in the north area was improved to some extent.

  18. Operational benefits obtained by implementing a remote monitoring and control system at CEGAS (Gas Company of Ceara, Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Rui C.O. [Companhia de Gas do Ceara (CEGAS), Fortaleza, CE (Brazil); Zamponha, Rogerio S. [SOFTBRASIL, Sao Paulo, SP (Brazil)

    2009-07-01

    CEGAS (Gas Company of Ceara) recently implemented an automated remote monitoring and control system at the Natural Gas Stations located within the city of Fortaleza. The main purposes to implement the project were to install a better operational platform, allowing CEGAS to analyze its operational conditions and to measure customer's consumption in real time. The data communication infra-structure chosen was GPRS/GSM, due to it's low deployment cost and coverage availability. The first phase of the project comprised 50 vehicular natural gas stations. The project was successfully installed, and became the 1{sup st} project at this type to run efficiently over a GPRS infra-structure in Brazil for gas monitoring, with reliable control and data communication. This document intends to present the reasons that lead CEGAS to invest in such a system, the technology deployed and the benefits achieved. (author)

  19. Program and abstracts of the offshore oil and gas environmental effects monitoring workshop : approaches and technologies

    International Nuclear Information System (INIS)

    2003-01-01

    The offshore petroleum industry in eastern Canada has expanded rapidly, with exploration and production activities taking place over a wide range of oceanographic conditions. This workshop, hosted by Canada's largest marine research institute, was held to advance the understanding of environmental impacts from offshore oil and gas activity. In particular, it examined how information derived from environmental effects monitoring (EEM) programs contribute to improved drilling and production operations, mitigation measures, and the revision of regulations for waste treatment. The workshop examined if EEM programs are providing valuable information, and how they can be improved. The themes of the 3 sessions which focused on ways to carry out EEM were: (1) EEM and environmental management, (2) EEM methodologies and lessons learned, and (3) EEM methodologies and technologies. Participants form around the world identified priority research needs and coordinated collaborative research efforts. Approximately 70 papers and posters were presented at the workshop, of which 19 have been indexed separately for inclusion in this database (Author)

  20. Real-time electronic monitoring of a pitted and leaking gas gathering pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Asperger, R.G.; Hewitt, P.G.

    1986-08-01

    Hydrogen patch, flush electrical resistance, and flush linear polarization proves wre used with flush coupons to monitor corrosion rates in a pitted and leaking sour gas gathering line. Four inhibitors were evaluated in stopping the leaks. Inhibitor residuals and the amount and ratio of water and condensate in the lines were measured at five locations along the line. The best inhibitor reduced reduced the pit-leak frequency by over a factor of 10. Inhibitor usage rate was optimized using the hydrogen patch current as a measure of the instantaneous corrosion rate. Improper pigging was identified as a cause of corrosion transients. This problem is discussed in relation to the pigging of pipelines in stratified flow where moving fluids are the carriers for continuously injected corrosion inhibitors.

  1. Monitoring and manipulating Higgs and Goldstone modes in a supersolid quantum gas.

    Science.gov (United States)

    Léonard, Julian; Morales, Andrea; Zupancic, Philip; Donner, Tobias; Esslinger, Tilman

    2017-12-15

    Higgs and Goldstone modes are collective excitations of the amplitude and phase of an order parameter that is related to the breaking of a continuous symmetry. We directly studied these modes in a supersolid quantum gas created by coupling a Bose-Einstein condensate to two optical cavities, whose field amplitudes form the real and imaginary parts of a U(1)-symmetric order parameter. Monitoring the cavity fields in real time allowed us to observe the dynamics of the associated Higgs and Goldstone modes and revealed their amplitude and phase nature. We used a spectroscopic method to measure their frequencies, and we gave a tunable mass to the Goldstone mode by exploring the crossover between continuous and discrete symmetry. Our experiments link spectroscopic measurements to the theoretical concept of Higgs and Goldstone modes. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  2. Artificial intelligence system for the monitoring of natural gas production systems; Intelligente Ueberwachung von Erdgasfoerderanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Tschaetsch, H.U.

    2001-02-01

    The article explains a novel, artificial intelligence-based system called HISS (Human Interface Supervision System) which has been installed as a prototype for the monitoring of a natural gas production site at Thoense near Hannover/Germany. The system is capable to perform audio-visual and smelling functions, analogous to the human sensory perception. (orig./CB) [German] Die Aufrechterhaltung eines einwandfreien Betriebszustandes von technischen Anlagen durch staendige Kontrollen und regelmaessige Wartungsarbeiten ist haeufig eine aufwendige und kostspielige Angelegenheit. Gleichwohl ist sie - sowohl was die Frage der Sicherheit als auch des Umweltschutzes anbelangt - unentbehrlich. Die Erdgasfoerderanlage Thoense bei Hannover wird von einem intelligenten Ueberwachungssystem, HISS - Human Interface Supervision System, kontrolliert, das die menschlichen Eigenschaften sehen, hoeren und riechen beherrscht. (orig.)

  3. Monitoring of radon gas in caves of the Yorkshire Dales, United Kingdom

    International Nuclear Information System (INIS)

    Langridge, D; Stokes, R P; Jackson, C P

    2010-01-01

    A number of vocational training courses are held in caves in the Yorkshire Dales region of the United Kingdom. The instructors and students involved in these courses have the potential to be exposed to enhanced levels of radon ( 222 Rn) and its progeny as a result of their occupations. A prior radiological risk assessment for the training courses recommended that an environmental monitoring programme be carried out to establish the radon concentrations in the caves, and that the caving instructors wear personal radon dosemeters. Radon gas concentrations varied seasonally, being at their highest in summer and their lowest in winter. The lowest result was 40 Bq m -3 recorded in Lower Longchurn cave during winter, whilst the highest result was 4440 Bq m -3 recorded in Crackpot cave during the summer. As the individuals involved in the caving are entering atmospheres with radon gas concentrations in excess of 400 Bq m -3 , the Ionising Radiation Regulations 1999 (GB Parliament 2000 Ionising Radiations Regulations 1999 (London: Stationary Office) SI 1999/3232) apply. A system of work is therefore in place to control exposure to radon. This system of work stipulates an initial dose investigation level of 1 mSv, a second dose investigation level of 2 mSv and an annual dose limit of 6 mSv. The highest annual dose recorded to date is 2.2 mSv, although the average (median) annual dose is only 0.5 mSv.

  4. Low-Power, Chip-Scale, Carbon Dioxide Gas Sensors for Spacesuit Monitoring

    Science.gov (United States)

    Rani, Asha; Shi, Chen; Thomson, Brian; Debnath, Ratan; Wen, Boamei; Motayed, Abhishek; Chullen, Cinda

    2018-01-01

    N5 Sensors, Inc. through a Small Business Technology Transfer (STTR) contract award has been developing ultra-small, low-power carbon dioxide (CO2) gas sensors, suited for monitoring CO2 levels inside NASA spacesuits. Due to the unique environmental conditions within the spacesuits, such as high humidity, large temperature swings, and operating pressure swings, measurement of key gases relevant to astronaut's safety and health such as(CO2), is quite challenging. Conventional non-dispersive infrared absorption based CO2 sensors present challenges inside the spacesuits due to size, weight, and power constraints, along with the ability to sense CO2 in a high humidity environment. Unique chip-scale, nanoengineered chemiresistive gas-sensing architecture has been developed for this application, which can be operated in a typical space-suite environmental conditions. Unique design combining the selective adsorption properties of the nanophotocatalytic clusters of metal-oxides and metals, provides selective detection of CO2 in high relative humidity conditions. All electronic design provides a compact and low-power solution, which can be implemented for multipoint detection of CO2 inside the spacesuits. This paper will describe the sensor architecture, development of new photocatalytic material for better sensor response, and advanced structure for better sensitivity and shorter response times.

  5. A Gas Chromatographic Continuous Emissions Monitoring System for the Determination of VOCs and HAPs.

    Science.gov (United States)

    Coleman, William M; Gordon, Bert M

    1996-01-01

    This article describes a new gas chromatography-based emissions monitoring system for measuring volatile organic compounds (VOCs) and hazardous air pollutants (HAPs). The system is composed of a dual-column gas chromatograph equipped with thermal conductivity detectors, in which separation is optimized for fast chromatography. The system has the necessary valving for stream selection, which allows automatic calibration of the system at predetermined times and successive measurement of individual VOCs before and after a control device. Nine different VOCs (two of which are HAPs), plus methane (CH4) and carbon dioxide (CO2) are separated and quantified every two minutes. The accuracy and precision of this system has been demonstrated to be greater than 95%. The system employs a mass flow measurement device and also calculates and displays processed emission data, such as control device efficiency and total weight emitted during given time periods. Two such systems have been operational for one year in two separate gravure printing facilities; minimal upkeep is required, about one hour per month. One of these systems, used before and after a carbon adsorber, has been approved by the pertinent local permitting authority.

  6. Strategy for monitoring and ensuring safe operation of Russian gas transportation systems

    Directory of Open Access Journals (Sweden)

    Dudin Sergey

    2017-01-01

    Full Text Available The authors examined the legislative framework of the Russian Federation operating in the field of industrial safety, and described how to obtain a license to operate hazardous production facilities. The paper demonstrates that the importance should be given to the quality and completeness of the background information, as well as the choice of inspection strategy in evaluating the technical condition of the line section of main gas pipelines. As a part of a package of measures to ensure industrial safety and technical reliability of existing gas pipelines it is proposed to carry out conditioning of their line sections. The paper describes general requirements for pipeline inspection, which include: detection efficiency of dangerous damages and major leaks, maximum accuracy of detection of the defect location, continuity of monitoring throughout the entire range of operation modes of the pipeline, cost recovery at the stages of development and operation of control systems, forecasting the state of the pipeline and the effects of accidents. In practice, these parameters have the prevailing significance.

  7. Application of surface–downhole combined microseismic monitoring technology in the Fuling shale gas field and its enlightenment

    Directory of Open Access Journals (Sweden)

    Yaowen Liu

    2017-01-01

    Full Text Available The Fuling shale gas field in the Sichuan Basin, as a national shale gas demonstration area, is the largest commercially developed shale gas field in the world except those in North America. The fracturing technology in the mode of “well factory” has been applied widely in the gas field, but it is necessary to perform further investigation on the way to evaluate effectively the fracturing effect of multi-well platform “well factory” and the distribution laws of its induced fracture networks. In this paper, the fractures induced by the “well factory” at the JY 48 platform were real-time monitored by a surface–downhole combined microseismic monitoring technology. The geometric size and extension direction of artificial fractures induced in the model of “well factory” fracturing in the Jiaoshiba block of Fuling Shale Gas Field were preliminarily understood. Moreover, the fracturing parameters under the mode of “well factory” were recognized by using the comprehensive interpretation results of surface–downhole combined microseismic monitoring technology, together with the SRV fracturing prediction chart. Eventually, the distribution laws of artificial fractures during the “well-factory-zipper” fracturing in the Fuling Shale Gas Field were clarified definitely. This paper provides guidance for the optimization of fracturing parameters at the later stage.

  8. Dissolving method for nuclear fuel oxide

    International Nuclear Information System (INIS)

    Tomiyasu, Hiroshi; Kataoka, Makoto; Asano, Yuichiro; Hasegawa, Shin-ichi; Takashima, Yoichi; Ikeda, Yasuhisa.

    1996-01-01

    In a method of dissolving oxides of nuclear fuels in an aqueous acid solution, the oxides of the nuclear fuels are dissolved in a state where an oxidizing agent other than the acid is present together in the aqueous acid solution. If chlorate ions (ClO 3 - ) are present together in the aqueous acid solution, the chlorate ions act as a strong oxidizing agent and dissolve nuclear fuels such as UO 2 by oxidation. In addition, a Ce compound which generates Ce(IV) by oxidation is added to the aqueous acid solution, and an ozone (O 3 ) gas is blown thereto to dissolve the oxides of nuclear fuels. Further, the oxides of nuclear fuels are oxidized in a state where ClO 2 is present together in the aqueous acid solution to dissolve the oxides of nuclear fuels. Since oxides of the nuclear fuels are dissolved in a state where the oxidizing agent is present together as described above, the oxides of nuclear fuels can be dissolved even at a room temperature, thereby enabling to use a material such as polytetrafluoroethylene and to dissolve the oxides of nuclear fuels at a reduced cost for dissolution. (T.M.)

  9. Design of an Online Fission Gas Monitoring System for Post-irradiation Examination Heating Tests of Coated Fuel Particles for High-Temperature Gas-Cooled Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Dawn Scates

    2010-10-01

    A new Fission Gas Monitoring System (FGMS) has been designed at the Idaho National Laboratory (INL) for use of monitoring online fission gas-released during fuel heating tests. The FGMS will be used with the Fuel Accident Condition Simulator (FACS) at the Hot Fuels Examination Facility (HFEF) located at the Materials and Fuels Complex (MFC) within the INL campus. Preselected Advanced Gas Reactor (AGR) TRISO (Tri-isotropic) fuel compacts will undergo testing to assess the fission product retention characteristics under high temperature accident conditions. The FACS furnace will heat the fuel to temperatures up to 2,000ºC in a helium atmosphere. Released fission products such as Kr and Xe isotopes will be transported downstream to the FGMS where they will accumulate in cryogenically cooledcollection traps and monitored with High Purity Germanium (HPGe) detectors during the heating process. Special INL developed software will be used to monitor the accumulated fission products and will report data in near real-time. These data will then be reported in a form that can be readily available to the INL reporting database. This paper describes the details of the FGMS design, the control and acqusition software, system calibration, and the expected performance of the FGMS. Preliminary online data may be available for presentation at the High Temperature Reactor (HTR) conference.

  10. Thermo-power in Brazil: diagnosis of control and monitoring of gas emissions

    International Nuclear Information System (INIS)

    Xavier, E.E.; Magrini, Alessandra; Rosa, L.P.; Santos, M.A. dos

    2004-01-01

    In parallel to Brazil's recent supply crisis, the privatization process of its power sector has drastically reshaped the nation's energy matrix. From a profile based mainly on hydro-power generation, this sector is being reshaped through a thermo-power plant construction program whose environmental repercussions will certainly be felt over the next few years. This paper offers a description of the thermo-power segment currently in operation, under construction and on the drawing board in Brazil, followed by the results of a diagnosis of the control and monitoring of the gas emissions by this segment. The methodology used for the exploratory analysis and to prepare the diagnosis consists of surveys through questionnaires completed by companies owning the thermo-power plants. After consolidating, processing and analyzing the findings reached through the replies sent in by the companies, it is concluded that thermo-power plants currently in operation lack control systems that would help reduce atmospheric pollution, and are not equipped with monitoring systems for these emissions. The thermo-power plants currently under construction and on the drawing board indicate a trend towards including these systems in their project designs, due to more stringent licensing processes

  11. Tunable Diode Laser Sensors to Monitor Temperature and Gas Composition in High-Temperature Coal Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Ronald [Stanford Univ., CA (United States); Whitty, Kevin [Univ. of Utah, Salt Lake City, UT (United States)

    2014-12-01

    The integrated gasification combined cycle (IGCC) when combined with carbon capture and storage can be one of the cleanest methods of extracting energy from coal. Control of coal and biomass gasification processes to accommodate the changing character of input-fuel streams is required for practical implementation of integrated gasification combined-cycle (IGCC) technologies. Therefore a fast time-response sensor is needed for real-time monitoring of the composition and ideally the heating value of the synthesis gas (here called syngas) as it exits the gasifier. The goal of this project was the design, construction, and demonstration an in situ laserabsorption sensor to monitor multiple species in the syngas output from practical-scale coal gasifiers. This project investigated the hypothesis of using laser absorption sensing in particulateladen syngas. Absorption transitions were selected with design rules to optimize signal strength while minimizing interference from other species. Successful in situ measurements in the dusty, high-pressure syngas flow were enabled by Stanford’s normalized and scanned wavelength modulation strategy. A prototype sensor for CO, CH4, CO2, and H2O was refined with experiments conducted in the laboratory at Stanford University, a pilot-scale at the University of Utah, and an engineering-scale gasifier at DoE’s National Center for Carbon Capture with the demonstration of a prototype sensor with technical readiness level 6 in the 2014 measurement campaign.

  12. Experience of molecular monitoring techniques in upstream oil and gas operations

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Anthony F.; Anfindsen, Hilde; Liengen, Turid; Molid, Solfrid [Statoil ASA (Denmark)

    2011-07-01

    For a numbers of years, molecular monitoring tools have been used in upstream oil and gas operations but the results have given only limited added value. This paper discusses the various techniques available for upstream molecular monitoring which provides scope for identification of microbial influenced problems. The methodology, which consists of analyzing solid samples using traditional as well as molecular techniques, is detailed. Two cases were studied with the objective of determining if microbial contamination was contributing to the problem. The first case was a study of amorphous deposits in production wells and mainly iron sulphide was found. The second study was of amorphous deposits in water injection wells and the analysis showed typical components of drilling and completion fluids with some organic material. Two more cases, corrosion of tubing in a water injection well and flow line corrosion, are discussed and the results are given. From the study, it can be concluded that failure can be due to several factors, chemical and biological.

  13. Breath acetone monitoring by portable Si:WO3 gas sensors

    International Nuclear Information System (INIS)

    Righettoni, Marco; Tricoli, Antonio; Gass, Samuel; Schmid, Alex; Amann, Anton; Pratsinis, Sotiris E.

    2012-01-01

    Highlights: ► Portable sensors were developed and tested for monitoring acetone in the human breath. ► Acetone concentrations down to 20 ppb were measured with short response times ( 3 nanostructured films was developed. The chamber volume was miniaturized while reaction-limited and transport-limited gas flow rates were identified and sensing temperatures were optimized resulting in a low detection limit of acetone (∼20 ppb) with short response (10–15 s) and recovery times (35–70 s). Furthermore, the sensor signal (response) was robust against variations of the exhaled breath flow rate facilitating application of these sensors at realistic relative humidities (80–90%) as in the human breath. The acetone content in the breath of test persons was monitored continuously and compared to that of state-of-the-art proton transfer reaction mass spectrometry (PTR-MS). Such portable devices can accurately track breath acetone concentration to become an alternative to more elaborate breath analysis techniques.

  14. Hierarchical leak detection and localization method in natural gas pipeline monitoring sensor networks.

    Science.gov (United States)

    Wan, Jiangwen; Yu, Yang; Wu, Yinfeng; Feng, Renjian; Yu, Ning

    2012-01-01

    In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initial recognition phase, a multi-classifier model based on SVM is constructed and characteristic parameters are sent as input vectors to the multi-classifier for initial recognition. In the final decision phase, an improved evidence combination rule is designed to integrate initial recognition results for final decisions. Furthermore, a weighted average localization algorithm based on time difference of arrival is introduced for determining the leak point's position. Experimental results illustrate that this hierarchical pipeline leak detection and localization method could effectively improve the accuracy of the leak point localization and reduce the undetected rate as well as false alarm rate.

  15. Hierarchical Leak Detection and Localization Method in Natural Gas Pipeline Monitoring Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ning Yu

    2011-12-01

    Full Text Available In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initial recognition phase, a multi-classifier model based on SVM is constructed and characteristic parameters are sent as input vectors to the multi-classifier for initial recognition. In the final decision phase, an improved evidence combination rule is designed to integrate initial recognition results for final decisions. Furthermore, a weighted average localization algorithm based on time difference of arrival is introduced for determining the leak point’s position. Experimental results illustrate that this hierarchical pipeline leak detection and localization method could effectively improve the accuracy of the leak point localization and reduce the undetected rate as well as false alarm rate.

  16. Hierarchical Leak Detection and Localization Method in Natural Gas Pipeline Monitoring Sensor Networks

    Science.gov (United States)

    Wan, Jiangwen; Yu, Yang; Wu, Yinfeng; Feng, Renjian; Yu, Ning

    2012-01-01

    In light of the problems of low recognition efficiency, high false rates and poor localization accuracy in traditional pipeline security detection technology, this paper proposes a type of hierarchical leak detection and localization method for use in natural gas pipeline monitoring sensor networks. In the signal preprocessing phase, original monitoring signals are dealt with by wavelet transform technology to extract the single mode signals as well as characteristic parameters. In the initial recognition phase, a multi-classifier model based on SVM is constructed and characteristic parameters are sent as input vectors to the multi-classifier for initial recognition. In the final decision phase, an improved evidence combination rule is designed to integrate initial recognition results for final decisions. Furthermore, a weighted average localization algorithm based on time difference of arrival is introduced for determining the leak point’s position. Experimental results illustrate that this hierarchical pipeline leak detection and localization method could effectively improve the accuracy of the leak point localization and reduce the undetected rate as well as false alarm rate. PMID:22368464

  17. Monitoring gas-phase CO2 in the headspace of champagne glasses through combined diode laser spectrometry and micro-gas chromatography analysis.

    Science.gov (United States)

    Moriaux, Anne-Laure; Vallon, Raphaël; Parvitte, Bertrand; Zeninari, Virginie; Liger-Belair, Gérard; Cilindre, Clara

    2018-10-30

    During Champagne or sparkling wine tasting, gas-phase CO 2 and volatile organic compounds invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Gas-phase CO 2 in excess can even cause a very unpleasant tingling sensation perturbing both ortho- and retronasal olfactory perception. Monitoring as accurately as possible the level of gas-phase CO 2 above glasses is therefore a challenge of importance aimed at better understanding the close relationship between the release of CO 2 and a collection of various tasting parameters. Here, the concentration of CO 2 found in the headspace of champagne glasses served under multivariate conditions was accurately monitored, all along the 10 min following pouring, through a new combined approach by a CO 2 -Diode Laser Sensor and micro-gas chromatography. Our results show the strong impact of various tasting conditions (volume dispensed, intensity of effervescence, and glass shape) on the release of gas-phase CO 2 above the champagne surface. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. A fence line noble gas monitoring system for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Grasty, R.L.; Hovgaard, J.; LaMarre, J.R

    2001-07-01

    A noble gas monitoring system has been installed at Ontario Power Generations' Pickering Nuclear Generating Station (PNGS) near Toronto, Canada. This monitoring system allows a direct measure of air kerma from external radiation instead of calculating this based on plant emission data and meteorological models. This has resulted in a reduction in the reported effective dose from external radiation by a factor of at least ten. The system consists of nine self-contained units, each with a 7.6 cm x 7.6 cm (3 inch x 3 inch) NaI(Tl) detector that is calibrated for air kerma. The 512-channel gamma ray spectral information is downloaded daily from each unit to a central computer where the data are stored and processed. A spectral stripping procedure is used to remove natural background variations from the spectral windows used to monitor xenon-133 ({sup 133}Xe), xenon-135 ({sup 135}Xe), argon-41 ({sup 41}Ar), and skyshine radiation from the use of radiography sources. Typical monthly minimum detection limits in air kerma are 0.3 nGy for {sup 133}Xe, 0.7 nGy for {sup 135}Xe, 3 nGy for {sup 41}Ar and 2 nGy for skyshine radiation. Based on 9 months of continuous operation, the annualised air kerma due to {sup 133}Xe, {sup 135}Xe and {sup 41}Ar and skyshine radiation were 7 nGy, 8 nGy, 26 nGy and 107 nGy respectively. (author)

  19. Environmental monitoring report, 1974

    International Nuclear Information System (INIS)

    1975-01-01

    Results are reported of the effluent and environmental monitoring programs at the Pinellas Plant during 1974. Sample analyses revealed the on-site sewage treatment facility operated well within State of Florida Standards. Likewise, offsite discharges met the applicable standards for arsenic, biochemical oxygen demand, chlorides, chromium, copper, cyanides, detergents, dissolved oxygen, dissolved solids, fluorides, lead, mercury, nitrogen, oils and greases, phenols, pH, phosphorus, suspended solids, turbidity and zinc. The results of iron and specific conductance analyses showed levels in excess of state standards and are discussed in the body of the report. In addition to the non-radioactive parameters listed above, a small quantity of radioactive tritium oxide was released in the plant's liquid effluent. Small quantities of tritium gas, tritium oxide, and krypton-85 gas were released from the plant during the year. Average ground level concentrations of these radioisotopes were all significantly less than 1 percent of recommended guide for continuous nonoccupational exposure. (U.S.)

  20. Note: Real-time monitoring via second-harmonic interferometry of a flow gas cell for laser wakefield acceleration

    Science.gov (United States)

    Brandi, F.; Giammanco, F.; Conti, F.; Sylla, F.; Lambert, G.; Gizzi, L. A.

    2016-08-01

    The use of a gas cell as a target for laser wakefield acceleration (LWFA) offers the possibility to obtain stable and manageable laser-plasma interaction process, a mandatory condition for practical applications of this emerging technique, especially in multi-stage accelerators. In order to obtain full control of the gas particle number density in the interaction region, thus allowing for a long term stable and manageable LWFA, real-time monitoring is necessary. In fact, the ideal gas law cannot be used to estimate the particle density inside the flow cell based on the preset backing pressure and the room temperature because the gas flow depends on several factors like tubing, regulators, and valves in the gas supply system, as well as vacuum chamber volume and vacuum pump speed/throughput. Here, second-harmonic interferometry is applied to measure the particle number density inside a flow gas cell designed for LWFA. The results demonstrate that real-time monitoring is achieved and that using low backing pressure gas (<1 bar) and different cell orifice diameters (<2 mm) it is possible to finely tune the number density up to the 1019 cm-3 range well suited for LWFA.

  1. Note: Real-time monitoring via second-harmonic interferometry of a flow gas cell for laser wakefield acceleration.

    Science.gov (United States)

    Brandi, F; Giammanco, F; Conti, F; Sylla, F; Lambert, G; Gizzi, L A

    2016-08-01

    The use of a gas cell as a target for laser wakefield acceleration (LWFA) offers the possibility to obtain stable and manageable laser-plasma interaction process, a mandatory condition for practical applications of this emerging technique, especially in multi-stage accelerators. In order to obtain full control of the gas particle number density in the interaction region, thus allowing for a long term stable and manageable LWFA, real-time monitoring is necessary. In fact, the ideal gas law cannot be used to estimate the particle density inside the flow cell based on the preset backing pressure and the room temperature because the gas flow depends on several factors like tubing, regulators, and valves in the gas supply system, as well as vacuum chamber volume and vacuum pump speed/throughput. Here, second-harmonic interferometry is applied to measure the particle number density inside a flow gas cell designed for LWFA. The results demonstrate that real-time monitoring is achieved and that using low backing pressure gas (<1 bar) and different cell orifice diameters (<2 mm) it is possible to finely tune the number density up to the 10(19) cm(-3) range well suited for LWFA.

  2. Note: Real-time monitoring via second-harmonic interferometry of a flow gas cell for laser wakefield acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Brandi, F., E-mail: fernando.brandi@ino.it [Intense Laser Irradiation Laboratory (ILIL), Istituto Nazionale di Ottica (INO-CNR), Via Moruzzi 1, 56124 Pisa (Italy); Istituto Italiano di Tecnologia (IIT), Via Morego 30, 16163 Genova (Italy); Giammanco, F.; Conti, F. [Dipartimento di Fisica, Università degli Studi di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Plasma Diagnostics and Technologies Ltd., via Matteucci n.38/D, 56124 Pisa (Italy); Sylla, F. [SourceLAB SAS, 86 Rue de Paris, 91400 Orsay (France); Lambert, G. [LOA, ENSTA ParisTech, CNRS, Ecole Polytechnique, Université Paris-Saclay, 828 bd des Maréchaux, 91762 Palaiseau Cedex (France); Gizzi, L. A. [Intense Laser Irradiation Laboratory (ILIL), Istituto Nazionale di Ottica (INO-CNR), Via Moruzzi 1, 56124 Pisa (Italy)

    2016-08-15

    The use of a gas cell as a target for laser wakefield acceleration (LWFA) offers the possibility to obtain stable and manageable laser-plasma interaction process, a mandatory condition for practical applications of this emerging technique, especially in multi-stage accelerators. In order to obtain full control of the gas particle number density in the interaction region, thus allowing for a long term stable and manageable LWFA, real-time monitoring is necessary. In fact, the ideal gas law cannot be used to estimate the particle density inside the flow cell based on the preset backing pressure and the room temperature because the gas flow depends on several factors like tubing, regulators, and valves in the gas supply system, as well as vacuum chamber volume and vacuum pump speed/throughput. Here, second-harmonic interferometry is applied to measure the particle number density inside a flow gas cell designed for LWFA. The results demonstrate that real-time monitoring is achieved and that using low backing pressure gas (<1 bar) and different cell orifice diameters (<2 mm) it is possible to finely tune the number density up to the 10{sup 19} cm{sup −3} range well suited for LWFA.

  3. Natural Gas Storage Seismic Monitoring Suivi sismique des stockages de gaz naturel

    Directory of Open Access Journals (Sweden)

    Mari J.L.

    2011-02-01

    Full Text Available IFP Energies nouvelles, CGGVeritas and GDF Suez have conducted together, since 1980, a series of seismic monitoring experiments in order to detect and follow the movements of the gas plume in natural gas geologic storages. Surface and well seismic surveys were carried out at different stages of the storage life. Permanent receiver arrays have been set down in wells. Permanent sources have been designed. Sources and receivers have been used to follow continuously the storage cycle during several years, providing time measurement accuracy within a tenth of a millisecond. Gas intrusion into an aquifer leads to an increase in the arrival times of reflections beneath the storage reservoir and to a variation of the reflection amplitudes at top and bottom of the reservoirs. Progressive variations of the seismic parameters may be followed during the initial infill period. Further movements of the gas plume with the annual in/out cycles are more difficult to follow, because of the simultaneous presence of gas and water in the pores. Arrival time variations of some tenths of a millisecond may be detected and measured. Saturations, using accurate picking of the arrival times, can be estimated in favourable cases. Because of the higher density of carbon dioxide, when stored in a supercritical phase, sensitivity of the seismic parameters, velocity, density and acoustic impedance to saturation variations will be about twice smaller for CO2 storages than it is for methane. IFP Energies nouvelles, la CGGVeritas et GDF Suez ont mené ensemble, depuis 1980, de nombreuses expériences de monitoring sismique afin de détecter et de suivre les mouvements du gaz dans des stockages géologiques de gaz naturel. Des acquisitions ont été réalisées à différents stades de la vie du stockage tant en sismique de surface qu’en sismique de puits. Des antennes de récepteurs permanentes ont été construites et implantées dans des puits. Des sources permanentes ont

  4. Strategies for Detecting Hidden Geothermal Systems by Near-Surface Gas Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Lewicki, Jennifer L.; Oldenburg, Curtis M.

    2004-12-15

    ''Hidden'' geothermal systems are those systems above which hydrothermal surface features (e.g., hot springs, fumaroles, elevated ground temperatures, hydrothermal alteration) are lacking. Emissions of moderate to low solubility gases (e.g., CO2, CH4, He) may be one of the primary near-surface signals from these systems. Detection of anomalous gas emissions related to hidden geothermal systems may therefore be an important tool to discover new geothermal resources. This study investigates the potential for CO2 detection and monitoring in the subsurface and above ground in the near-surface environment to serve as a tool to discover hidden geothermal systems. We focus the investigation on CO2 due to (1) its abundance in geothermal systems, (2) its moderate solubility in water, and (3) the wide range of technologies available to monitor CO2 in the near-surface environment. However, monitoring in the near-surface environment for CO2 derived from hidden geothermal reservoirs is complicated by the large variation in CO2 fluxes and concentrations arising from natural biological and hydrologic processes. In the near-surface environment, the flow and transport of CO2 at high concentrations will be controlled by its high density, low viscosity, and high solubility in water relative to air. Numerical simulations of CO2 migration show that CO2 concentrations can reach very high levels in the shallow subsurface even for relatively low geothermal source CO2 fluxes. However, once CO2 seeps out of the ground into the atmospheric surface layer, surface winds are effective at dispersing CO2 seepage. In natural ecological systems in the absence of geothermal gas emissions, near-surface CO2 fluxes and concentrations are primarily controlled by CO2 uptake by photosynthesis, production by root respiration, and microbial decomposition of soil/subsoil organic matter, groundwater degassing, and exchange with the atmosphere. Available technologies for monitoring CO2 in

  5. Application network for monitoring of green house gas emission from lithosphere in Khibina territories

    Science.gov (United States)

    Asavin, Alex; Nivin, Valentin; Litvinov, Artur; Chesalova, Elena; Baskov, Sergey

    2015-04-01

    The aim of project is to estimate the contribution of lithospheric flue gas emission of gases CH4, CO2, H2 in the general composition of atmospheric pollution of Arctic zone. The main task is organization of the ecological monitoring in the area of exploitation of large apatite and rare earth ore deposit from Khibine massive on the base of modern WSN (wireless sensor network) technologies. Application network consist from sensors of gas H2, CH4, CO2, complex autonomous equipment for measurement temperature, pressure, humidity and network of telecommunications (used ZigBee protocol). Our project offer technical decisions for experimentally-methodical monitoring network on the base of WSN and the high-sensitive sensors of hydrogen and methane, software and electronic equipment with a transmitter network. This work is the first project in Russia. The advantages of this technology is autonomous work (to several months and more), high-frequency programmable measurement of gas sensor, low cost (on one node of network), possibility to connect to one node of supervision a several types of sensors. And as a result is complex monitoring of environment. It has long been known that the pollution in Arctic Khibine and Lovosero region contains unusually high levels of hydrocarbon gases (HCG) [Petersilie,1964]. The presence of these gases has a number of practical implications and it is therefore important to understand their source and distribution. Among alkaline intrusive complexes with high (for magmatic rocks) concentrations of hydrocarbon and hydrogen- hydrocarbon gases occluded as fluid inclusions in minerals. The Khibina and Lovozero massives are well known, as region of spontaneous emissions of these gases from lithosphere [Khitarov et al., 1979; Ikorskii et al., 1992; Beeskow 2007; Nivin 2005, 2009]. The presence of the HCG, however, raises a number of questions and possibilities. It is unclear how homogeneously the HCG are distributed through the complex? What is the

  6. Advanced cost-effective surface geochemical techniques for oil/gas/uranium exploration, environmental assessments and pipeline monitoring - a template for India

    International Nuclear Information System (INIS)

    Lafleur, Paul; Chanrasekharan, G.Y.V.N.; Rajender Rao, S.

    2011-01-01

    Advanced geochemical soil gas methods have been successfully developed for the exploration of oil/gas/uranium and for environmental assessments. Application of these cost-effective technologies in India can substantially reduce exploration risk while accelerating the development of oil/gas/uranium onshore resources. A reliable and effective monitoring system using geochemical soil gas surveys ensures that CO 2 Enhanced Oil Recovery operations as well as CO 2 sequestration projects are safe and acceptable for the disposal of CO 2 , Soil gas surveys along with other technologies can also be applied for monitoring of oil/gas pipelines for leakage, especially those that are old or pass through populated regions

  7. Monitoring of effects of land subsidence at Ameland-Oost, Netherlands. Evaluation after 18 years of natural gas exploration. Summary

    International Nuclear Information System (INIS)

    Eysink, W.D.; Wang, Z.; Dijkema, K.S.; Slim, P.A.; Dankers, N.M.J.A.; Sanders, M.E.; Van Dobben, H.F.; Krol, J.; Kersten, M.; Molenaar, W.; Doornhof, D.; Schoustra, S.; Veldwisch, W.

    2005-05-01

    After the start of the natural gas exploitation on the Dutch island Ameland in 1986 surveys were carried out from 1988 on to investigate and monitor the effect of the exploitation on land subsidence and related environmental effects. In this third report evaluated results of that survey over the last 18 years are presented and discussed [nl

  8. Cycle-by-cycle exhaust temperature monitoring for detection of misfiring and combustion instability in reciprocating natural gas engines

    Energy Technology Data Exchange (ETDEWEB)

    Gardiner, D.P. [Nexum Research Corp., Kingston, ON (Canada); Bardon, M.F. [Royal Military Coll. of Canada, Kingston, ON (Canada). Dept. of Mechanical Engineering

    2007-07-01

    The effectiveness of a cycle-by-cycle exhaust temperature monitoring system on engines operating at or near their fully rate load capacity was examined. Tests were conducted on stationary industrial natural gas engines. The study evaluated the monitoring system's ability to detect isolated single misfires, as well as combustion instability during misfire-free operations when the air/fuel ratio of the engine was adjusted to progressively lower settings. The combustion instability level of the engines was quantified by determining the relative variability of the groups of consecutive cycles. The coefficient of variation of indicated mean effective pressure (COV of IMEP) was used to examine cyclic variability. A combustion instability index was used to quantify cyclic variability with cycle-by-cycle exhaust temperature monitoring. Two engines were tested, notably a Cummins QSK 19G turbocharged natural gas engine; and a Waukesha VHP L5790G industrial natural gas engine. The tests demonstrated that cycle-by-cycle exhaust temperature monitoring system was capable of detecting misfiring and combustion instabilities in natural gas engines. 6 refs., 9 figs.

  9. Modern Processes of Hydrocarbon Migration and Re-Formation of Oil and Gas Fields (Based on the Results of Monitoring and Geochemical Studies)

    Science.gov (United States)

    Plotnikova, Irina; Salakhidinova, Gulmira; Nosova, Fidania; Pronin, Nikita; Ostroukhov, Sergey

    2015-04-01

    important fundamental task of exceptional practical importance. The reservoir water monitoring has been conducted in five wells that have penetrated the water-saturated, loosely aggregated zones of the South Tatarstan Arch's basement. The long-term testing resulted in the production of reservoir water from the basement. The sedimentary cover in these wells is blocked by the column, which prevents water cross-flowing from the sedimentary cover. The observations have shown that the levels, gas saturation, mineralisation, density, and composition of reservoir waters from the loosely aggregated zones of the basement change with time. The varying characteristics of the water include its component composition, redox potential, and amount of chlorine and some other components and trace elements. Compositional changes in gases of the loosely aggregated zones of the basement, variations in the gas saturation of reservoir waters and of their composition, the decreasing density of oil in the sedimentary cover, - all result from one cause. This cause is the movement of fluids (solutions and gases dissolved in them) through the loosely aggregated zones and faults of the Earth's crust and the sedimentary cover. The fluids mainly move vertically in an upward direction, although their migration through subhorizontal, loosely aggregated zones of the crystalline basement is also possible. Fluid migration still takes place in the Earth's crust of ancient platforms. This phenomenon indicates that some portions of the platforms - primarily, their margins - periodically resume tectonic activities. The fluid dynamic activity of the crust define the processes in the sedimentary cover. It affects the development of the sedimentary basin during the sedimentation period, and the formation of mineral deposits. The monitoring of the present-day movement of fluid systems in the loosely aggregated zones of the basement will permit the more detailed study of the present-day fluid regime in the upper

  10. Monitoring Volatile Organic Compounds (VOCs) in real-time on oil and natural gas production sites

    Science.gov (United States)

    Lupardus, R.; Franklin, S. B.

    2017-12-01

    Oil and Natural Gas (O&NG) development, production, infrastructure, and associated processing activities can be a substantial source of air pollution, yet relevant data and real-time quantification methods are lacking. In the current study, O&NG fugitive emissions of Volatile Organic Compounds (VOCs) were quantified in real-time and used to determine the spatial and temporal windows of exposure for proximate flora and fauna. Eleven O&NG sites on the Pawnee National Grassland in Northeastern Colorado were randomly selected and grouped according to production along with 13 control sites from three geographical locations. At each site, samples were collected 25 m from the wellhead in NE, SE, and W directions. In each direction, two samples were collected with a Gasmet DX4040 gas analyzer every hour from 8:00 am to 2:00 pm (6 hours total), July to October, 2016 (N=864). VOC concentrations generally increased during the 6 hr. day with the exception of N2O and were predominately the result of O&NG production and not vehicle exhaust. Thirteen of 24 VOCs had significantly different levels between production groups, frequently above reference standards and at biologically relevant levels for flora and fauna. The most biologically relevant VOCs, found at concentrations exceeding time weighted average permissible exposure limits (TWA PELs), were benzene and acrolein. Generalized Estimating Equations (GEEs) measured the relative quality of statistical models predicting benzene concentrations on sites. The data not only confirms that O&NG emissions are impacting the region, but also that this influence is present at all sites, including controls. Increased real-time VOC monitoring on O&NG sites is required to identify and contain fugitive emissions and to protect human and environmental health.

  11. A rapid and simple procedure for monitoring valproic acid by gas chromatography

    Directory of Open Access Journals (Sweden)

    Mohamed Said Mostafa

    2018-02-01

    Full Text Available Valproic acid (VPA, a widely used antiepileptic drug, has a narrow therapeutic range of 50-100 μg/mL and shows large individual variability. It is very important to monitor the trough VPA concentration using a reliable method. The aim of this study was to develop and validate a rapid gas chromatographic (GC technique for VPA quantification in human plasma and to compare it with the traditional immunoassay method. VPA extraction from human serum was efficient by dichloromethane and hydrochloric acid using octanoic acid as an internal standard. GC analysis was performed using a gas-chromatograph equipped with a flame ionization detector (GC/FID. VPA detection and quantification were accomplished isothermally at 135°C on a Gs-BP 100% dimethylpolysiloxane capillary column (10 m×0.53 mm ID, 2.65 μm film thickness, Supelco, Bellefonte, PA. Injection port and detector temperature were 280°C. Retention times of VPA and internal standard were 1.83 min and 2.33 min, respectively. The calibration curve was linear over the concentration range of 5-320 μg/mL, with a lower limit of detection of 1.25 μg/mL. The internal and inter-day precision was less than 5.3% and 6.1%, respectively, and the accuracy was below 2.8%. VPA recovery was 94.6%. A quick and accurate method for VPA determination in human plasma was developed and validated. It resulted sufficiently selective and sensitive.

  12. Assessment of corrosion in the flue gas cleaning system using on-line monitoring

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Vendelbo Nielsen, Lars; Berggreen Petersen, Michael

    2015-01-01

    Amager unit 1 is a 350 MW multifuel suspension-fired plant commissioned in 2009 to fire biomass (straw and wood pellets). Increasing corrosion problems in the flue gas cleaning system were observed in the gas-gas preheater (GAFO), the booster fan and flue gas ducts. Chlorine containing corrosion ...

  13. Web-based continuous internal corrosion monitoring of a sweet natural gas pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Cauchi, Sam; Vorozcovs, Andrew [Fiber Optic Systems Technology Inc. (FOX-TEK), Bedford, Nova Scotia (Canada)

    2009-07-01

    Inspection of pipelines susceptible to internal corrosion is a key ingredient in maintaining their reliable throughput. While conventional inspection consisting of in line inspection, radiography and ultrasound remain the mainstay of most integrity programs, challenging circumstances in some cases make the availability of such data inadequate, cost prohibitive, and at times entirely unavailable. These scenarios include aggressive internal corrosion, expensive excavation conditions, low or stagnant flow, and non-piggable pipeline segments. While some gas pipelines in these circumstances are considered relatively low risk and low consequence, due to the significant reclamation costs and cleanup time associated with liquid pipelines, those areas identified as being high-risk are often high-consequence and thus require a specialized inspection solution. For areas deemed to be at high-risk, or areas of low-risk with high consequence, Electrical Field Mapping (EFM) has provided a practical solution to safe operation without introducing expensive and potentially dangerous dig programs. Historically, however, this inspection approach has required manual data acquisition as part of a scheduled EFM site visit schedule. Due to the tedious nature of this data acquisition approach, the remoteness of some pipeline inspection sites and the complexity of data analysis, it has been difficult to closely monitor the most critical assets on a continuous basis. The manual component of this approach also often eliminates EFM as a practical solution due to lack of properly trained personnel. In this paper, we will discuss a new approach to data acquisition where data is acquired, transmitted, analyzed, and displayed completely automatically and remotely with virtually no human overhead or recurring operating costs. An overview of the PinPoint monitoring setup covering 180 degrees of pipe circumference is described. This advanced EFM system allows operators to observe, essentially in real

  14. Vibration Monitoring of Gas Turbine Engines: Machine-Learning Approaches and Their Challenges

    Directory of Open Access Journals (Sweden)

    Ioannis Matthaiou

    2017-09-01

    Full Text Available In this study, condition monitoring strategies are examined for gas turbine engines using vibration data. The focus is on data-driven approaches, for this reason a novelty detection framework is considered for the development of reliable data-driven models that can describe the underlying relationships of the processes taking place during an engine’s operation. From a data analysis perspective, the high dimensionality of features extracted and the data complexity are two problems that need to be dealt with throughout analyses of this type. The latter refers to the fact that the healthy engine state data can be non-stationary. To address this, the implementation of the wavelet transform is examined to get a set of features from vibration signals that describe the non-stationary parts. The problem of high dimensionality of the features is addressed by “compressing” them using the kernel principal component analysis so that more meaningful, lower-dimensional features can be used to train the pattern recognition algorithms. For feature discrimination, a novelty detection scheme that is based on the one-class support vector machine (OCSVM algorithm is chosen for investigation. The main advantage, when compared to other pattern recognition algorithms, is that the learning problem is being cast as a quadratic program. The developed condition monitoring strategy can be applied for detecting excessive vibration levels that can lead to engine component failure. Here, we demonstrate its performance on vibration data from an experimental gas turbine engine operating on different conditions. Engine vibration data that are designated as belonging to the engine’s “normal” condition correspond to fuels and air-to-fuel ratio combinations, in which the engine experienced low levels of vibration. Results demonstrate that such novelty detection schemes can achieve a satisfactory validation accuracy through appropriate selection of two parameters of the

  15. Feasibility study for seismic monitoring of gas injection; Atsunyu gasu monitaringu no kanosei hyoka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, A.; Ogawa, T.; Yokota, T.; Shimada, N.; Onozuka, S.; Kono, F.; Miyagi, T. [Japan National Oil Corp., Tokyo (Japan)

    1998-10-30

    In this study, seismic monitoring of injected gas in a carbonate reservoir was investigated using multidisciplinary approach which consisted of geological/reservoir modeling, reservoir flow simulation, rock physics and seismic modeling. A case study was conducted over Lower Cretaceous carbonate reservoir offshore Abu Dhabi. The gas saturation and reservoir pressure data were obtained from the reservoir flow simulation. The velocity data of dry rock samples under the various conditions were also obtained from rock physics study. These outputs were converted to the velocity model using Gassmann's equation. The calculated velocity from Gassmann's equation is well correlated with velocity from laboratory measurements. Therefore we con confirm that the Gassmann's equation is applicable to estimate the velocity of the gas saturated reservoir rock. Based on the velocity model, synthetic seismic sections before and after gas injection were constructed in order to verify the influence of gas flood. As the results, amplitude difference between the two synthetic seismograms was observed at top and bottom reflectors of the reservoir zone. This amplitude variation is caused by both gas saturation change and pressure change. Although further investigation is needed to detect the cause of the variation, this study indicates the possibility of seismic reservoir monitoring. (author)

  16. Formation and migration of Natural Gases: gas composition and isotopes as monitors between source, reservoir and seep

    Science.gov (United States)

    Schoell, M.; Etiope, G.

    2015-12-01

    Natural gases form in tight source rocks at temperatures between 120ºC up to 200ºC over a time of 40 to 50my depending on the heating rate of the gas kitchen. Inferring from pyrolysis experiments, gases after primary migration, a pressure driven process, are rich in C2+ hydrocarbons (C2 to C5). This is consistent with gas compositions of oil-associated gases such as in the Bakken Shale which occur in immediate vicinity of the source with little migration distances. However, migration of gases along porous rocks over long distances (up to 200km in the case of the Troll field offshore Norway) changes the gas composition drastically as C2+ hydrocarbons tend to be retained/sequestered during migration of gas as case histories from Virginia and the North Sea will demonstrate. Similar "molecular fractionation" is observed between reservoirs and surface seeps. In contrast to gas composition, stable isotopes in gases are, in general, not affected by the migration process suggesting that gas migration is a steady state process. Changes in isotopic composition, from source to reservoir to surface seeps, is often the result of mixing of gases of different origins. Examples from various gas provinces will support this notion. Natural gas basins provide little opportunity of tracking and identifying gas phase separation. Future research on experimental phase separation and monitoring of gas composition and gas ratio changes e.g. various C2+ compound ratios over C1 or isomer ratios such as iso/n ratios in butane and pentane may be an avenue to develop tracers for phase separation that could possibly be applied to natural systems of retrograde natural condensate fields.

  17. Increasing gas producer profitability with virtual well visibility via an end-to-end, wireless Internet gas monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, M.; Coleman, K.; Beck, R.; Lyon, R.; Potts, R. [Northrock Resources Ltd., Calgary, AB (Canada); Benterud, K. [Zed.i solutions, Calgary, AB (Canada)

    2003-07-01

    Most gas producing companies still use 100-year old technology to measure gas volumes because of the prohibitive costs of implementing corporate wide electronic information systems to replace circular mechanical chart technology. This paper describes how Northrock Resources Ltd. increased profitability using Smart-Alek{sup TM} while avoiding high implementation costs. Smart-Alek is a new type of fully integrated end-to-end electronic gas flow measurement (GFM) system based on Field Intelligence Network and End User Interference (FINE). Smart-Alek can analyze gas production through public wireless communications and a web-browser delivery system. The system has enabled Northrock to increase gas volumes with more accurate measurement and reduced downtime. In addition, operating costs were also decreased because the frequency of well visits was reduced and the administrative procedures of data collection was more efficient. The real-time well visibility of the tool has proven to be very effective in optimizing business profitability. 9 refs., 1 tab., 9 figs.

  18. Increasing gas producer profitability with virtual well visibility via an end-to-end wireless Internet gas monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, M. [Northrock Resources Ltd., Calgary, AB (Canada); Benterud, K. [Zed.i solutions, Calgary, AB (Canada)

    2003-07-01

    This PowerPoint presentation describes how Northrock Resources Ltd. increased profitability using Smart-Alek{sup TM} while avoiding high implementation costs. Smart-Alek is a new type of fully integrated end-to-end electronic gas flow measurement (GFM) system based on Field Intelligence Network and End User Interference (FINE). Smart-Alek can analyze gas production through public wireless communications and a web-browser delivery system. The system has enabled Northrock to increase gas volumes with more accurate measurement and reduced downtime. In addition, operating costs have decreased because the frequency of well visits has been reduced and the administrative procedures of data collection is more efficient. The real-time well visibility of the tool has proven to be very effective in optimizing business profitability. 7 figs.

  19. Realtime Gas Emission Monitoring at Hazardous Sites Using a Distributed Point-Source Sensing Infrastructure

    Science.gov (United States)

    Manes, Gianfranco; Collodi, Giovanni; Gelpi, Leonardo; Fusco, Rosanna; Ricci, Giuseppe; Manes, Antonio; Passafiume, Marco

    2016-01-01

    This paper describes a distributed point-source monitoring platform for gas level and leakage detection in hazardous environments. The platform, based on a wireless sensor network (WSN) architecture, is organised into sub-networks to be positioned in the plant’s critical areas; each sub-net includes a gateway unit wirelessly connected to the WSN nodes, hence providing an easily deployable, stand-alone infrastructure featuring a high degree of scalability and reconfigurability. Furthermore, the system provides automated calibration routines which can be accomplished by non-specialized maintenance operators without system reliability reduction issues. Internet connectivity is provided via TCP/IP over GPRS (Internet standard protocols over mobile networks) gateways at a one-minute sampling rate. Environmental and process data are forwarded to a remote server and made available to authenticated users through a user interface that provides data rendering in various formats and multi-sensor data fusion. The platform is able to provide real-time plant management with an effective; accurate tool for immediate warning in case of critical events. PMID:26805832

  20. Realtime Gas Emission Monitoring at Hazardous Sites Using a Distributed Point-Source Sensing Infrastructure

    Directory of Open Access Journals (Sweden)

    Gianfranco Manes

    2016-01-01

    Full Text Available This paper describes a distributed point-source monitoring platform for gas level and leakage detection in hazardous environments. The platform, based on a wireless sensor network (WSN architecture, is organised into sub-networks to be positioned in the plant’s critical areas; each sub-net includes a gateway unit wirelessly connected to the WSN nodes, hence providing an easily deployable, stand-alone infrastructure featuring a high degree of scalability and reconfigurability. Furthermore, the system provides automated calibration routines which can be accomplished by non-specialized maintenance operators without system reliability reduction issues. Internet connectivity is provided via TCP/IP over GPRS (Internet standard protocols over mobile networks gateways at a one-minute sampling rate. Environmental and process data are forwarded to a remote server and made available to authenticated users through a user interface that provides data rendering in various formats and multi-sensor data fusion. The platform is able to provide real-time plant management with an effective; accurate tool for immediate warning in case of critical events.

  1. Gas centrifuge enrichment plants inspection frequency and remote monitoring issues for advanced safeguards implementation

    International Nuclear Information System (INIS)

    Boyer, Brian David; Erpenbeck, Heather H.; Miller, Karen A.; Ianakiev, Kiril D.; Reimold, Benjamin A.; Ward, Steven L.; Howell, John

    2010-01-01

    Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low enriched uranium (LEU) production, detect undeclared LEU production and detect high enriched uranium (BEU) production with adequate probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and 235 U enrichment of declared cylinders of uranium hexafluoride that are used in the process of enrichment at GCEPs. This paper contains an analysis of how possible improvements in unattended and attended NDA systems including process monitoring and possible on-site destructive analysis (DA) of samples could reduce the uncertainty of the inspector's measurements providing more effective and efficient IAEA GCEPs safeguards. We have also studied a few advanced safeguards systems that could be assembled for unattended operation and the level of performance needed from these systems to provide more effective safeguards. The analysis also considers how short notice random inspections, unannounced inspections (UIs), and the concept of information-driven inspections can affect probability of detection of the diversion of nuclear material when coupled to new GCEPs safeguards regimes augmented with unattended systems. We also explore the effects of system failures and operator tampering on meeting safeguards goals for quantity and timeliness and the measures needed to recover from such failures and anomalies.

  2. A Greenhouse-Gas Information System: Monitoring and Validating Emissions Reporting and Mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Jonietz, Karl K. [Los Alamos National Laboratory; Dimotakis, Paul E. [JPL/CAL Tech; Rotman, Douglas A. [Lawrence Livermore National Laboratory; Walker, Bruce C. [Sandia National Laboratory

    2011-09-26

    This study and report focus on attributes of a greenhouse-gas information system (GHGIS) needed to support MRV&V needs. These needs set the function of such a system apart from scientific/research monitoring of GHGs and carbon-cycle systems, and include (not exclusively): the need for a GHGIS that is operational, as required for decision-support; the need for a system that meets specifications derived from imposed requirements; the need for rigorous calibration, verification, and validation (CV&V) standards, processes, and records for all measurement and modeling/data-inversion data; the need to develop and adopt an uncertainty-quantification (UQ) regimen for all measurement and modeling data; and the requirement that GHGIS products can be subjected to third-party questioning and scientific scrutiny. This report examines and assesses presently available capabilities that could contribute to a future GHGIS. These capabilities include sensors and measurement technologies; data analysis and data uncertainty quantification (UQ) practices and methods; and model-based data-inversion practices, methods, and their associated UQ. The report further examines the need for traceable calibration, verification, and validation processes and attached metadata; differences between present science-/research-oriented needs and those that would be required for an operational GHGIS; the development, operation, and maintenance of a GHGIS missions-operations center (GMOC); and the complex systems engineering and integration that would be required to develop, operate, and evolve a future GHGIS.

  3. Realtime Gas Emission Monitoring at Hazardous Sites Using a Distributed Point-Source Sensing Infrastructure.

    Science.gov (United States)

    Manes, Gianfranco; Collodi, Giovanni; Gelpi, Leonardo; Fusco, Rosanna; Ricci, Giuseppe; Manes, Antonio; Passafiume, Marco

    2016-01-20

    This paper describes a distributed point-source monitoring platform for gas level and leakage detection in hazardous environments. The platform, based on a wireless sensor network (WSN) architecture, is organised into sub-networks to be positioned in the plant's critical areas; each sub-net includes a gateway unit wirelessly connected to the WSN nodes, hence providing an easily deployable, stand-alone infrastructure featuring a high degree of scalability and reconfigurability. Furthermore, the system provides automated calibration routines which can be accomplished by non-specialized maintenance operators without system reliability reduction issues. Internet connectivity is provided via TCP/IP over GPRS (Internet standard protocols over mobile networks) gateways at a one-minute sampling rate. Environmental and process data are forwarded to a remote server and made available to authenticated users through a user interface that provides data rendering in various formats and multi-sensor data fusion. The platform is able to provide real-time plant management with an effective; accurate tool for immediate warning in case of critical events.

  4. Model-based energy efficiency monitoring of gas-fired furnaces; Modellgestuetztes Energieeffizienz-Monitoring an Industriefeuerungen

    Energy Technology Data Exchange (ETDEWEB)

    Gose, Sven; Schult, Stefan; Sternberg, Jost [SAACKE GmbH, Bremen (Germany)

    2011-09-15

    This paper first describes the losses and the saving potential of heat generation plants and contrasts the usual characteristic numbers for assessing the energy efficiency. As these numbers describe a discontinuous process often only insufficiently, the characteristic number ''fuel efficiency'' is introduced. This number can only be calculated through a continuous monitoring system. The benefits of such a monitoring system are demonstrated by an example. (orig.)

  5. Amperometric Gas Sensors as a Low Cost Emerging Technology Platform for Air Quality Monitoring Applications: A Review.

    Science.gov (United States)

    Baron, Ronan; Saffell, John

    2017-11-22

    This review examines the use of amperometric electrochemical gas sensors for monitoring inorganic gases that affect urban air quality. First, we consider amperometric gas sensor technology including its development toward specifically designed air quality sensors. We then review recent academic and research organizations' studies where this technology has been trialed for air quality monitoring applications: early studies showed the potential of electrochemical gas sensors when colocated with reference Air Quality Monitoring (AQM) stations. Spatially dense networks with fast temporal resolution provide information not available from sparse AQMs with longer recording intervals. We review how this technology is being offered as commercial urban air quality networks and consider the remaining challenges. Sensors must be sensitive, selective, and stable; air quality monitors/nodes must be electronically and mechanically well designed. Data correction is required and models with differing levels of sophistication are being designed. Data analysis and validation is possibly the biggest remaining hurdle needed to deliver reliable concentration readings. Finally, this review also considers the roles of companies, urban infrastructure requirements, and public research in the development of this technology.

  6. Transit of Natural Gas. Monitoring Report on the Implementation of the Transit Provisions of the Energy Charter Treaty

    International Nuclear Information System (INIS)

    2007-03-01

    Natural gas is transported over increasingly large distances from producers to consumers. Most of this transportation takes place by pipelines and often involves crossing multiple national borders. Recent events demonstrated that disputes over energy transit can quickly have multilateral implications for gas supply, demonstrating the need for a framework for reliable cross-border gas flows. The Energy Charter Treaty (ECT) provides a set of binding rules that cover the entire energy chain, including the terms to transport energy across various national jurisdictions. The transit provisions of the Treaty support the reliability of established flows and the creation of new transport capacity, thus contributing to the reliability of gas transit. The Energy Charter's Group on Trade and Transit monitors and assists in the implementation of the ECT and its instruments on trade and transit and suggests improvements of implementation. The present report monitors the implementation of the Energy Charter transit principles for natural gas by giving an analysis of its legislative and practical aspects in selected member countries of the ECT constituency

  7. 40 CFR 60.107a - Monitoring of emissions and operations for fuel gas combustion devices.

    Science.gov (United States)

    2010-07-01

    ... or less. In the case of a liquefied petroleum gas (LPG) product specification in the pressurized liquid state, the gas phase sulfur content should be evaluated assuming complete vaporization of the LPG... for fuel gas combustion devices. 60.107a Section 60.107a Protection of Environment ENVIRONMENTAL...

  8. Comparative evaluation of online oil and gas monitor; Avaliacao de monitores de teor de oleo e graxa em linha

    Energy Technology Data Exchange (ETDEWEB)

    Louvisse, Ana Maria Travalloni; Pereira Junior, Oswaldo de Aquino; Jesus, Rafael Ferreira de; Santos, Lino Antonio Duarte dos; Lopes, Humberto Eustaquio [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    Petroleum is predominantly recovered in form of water in oil emulsions, which are stabilised by petroleum resins and asphaltenes, the colloidal disperse components of crude oil. The water phase, separated during the production process, consists of a dilute oil in water emulsion, commonly called produced water.There are a wide variety of methods for determination of oil in produced water that are commercially based on a number of technique. On line continuously monitoring shall be particularly useful in providing information to assist in optimising the separation process and also to attend the environmental legislation for discharge the produced water. There are a wide variety of on line oil in water monitors that are commercially available based on a number of technique. In this paper, a comparative evaluation was made between some methods of on line oil in water detecting. These are light scattering and ultraviolet fluorescence technique. A brief description of the optical methods will be discussed and some of associated problems and limitation are pointed. The work was done in a specific experimental set up that allows the simultaneous pumping of crude oil and water through a calibrated restriction in a pipe has been used. A permanent pressure drop induced by the restriction leads to the dispersion of the oil droplets in the water phase. The monitors based on light scattering technique tested show good agreement between monitor reading and the oil dispersion used. Otherwise for ultraviolet fluorescence based monitors show a significant effect of the variation of oil type. (author)

  9. Gas

    International Nuclear Information System (INIS)

    1996-01-01

    The French government has decided to modify the conditions of extension of local natural gas authorities to neighbouring districts. The European Union is studying the conditions of internal gas market with the objective of more open markets although considering public service requirements

  10. Terms of transactions monitoring on the French wholesale electricity and gas markets. Public consultation. Synthesis of contributions

    International Nuclear Information System (INIS)

    2008-01-01

    In its communication dated 16 April 2008, CRE published its practical methods used to monitor transactions concluded on the French electricity and gas markets. CRE invited any companies to comment on the practical arrangements of such monitoring activities. The monitoring system described by CRE is divided into two steps. In the first step, CRE wants to be able to request any information concerning transactions for physical delivery concluded after 1 January 2007. CRE will make an initial request that will focus on: - for electricity: transactions concluded in 2007 on yearly products for delivery in 2008 and 2009, base-load and peak-load; - for gas: transactions concluded in 2007 on seasonal and yearly products for delivery in 2008 and 2009, base-load and peak-load. The second step, based on feedback received, will see CRE liaise with market players and consider the possibility of setting up systematic procedures to gather transactions data. A final decision will be made by the end of 2008. 17 contributors responded to the public consultation. The remarks made on the practical methods used to gather data can be summarized along the following themes: Preamble: the monitoring principle; Theme 1: scope of transactions monitoring; Theme 2: content and format of requested data; Theme 3: procedures, transmission deadlines and confidentiality issues; Theme 4: stage II of systematic data gathering

  11. FEMO, A FLOW AND ENRICHMENT MONITOR FOR VERIFYING COMPLIANCE WITH INTERNATIONAL SAFEGUARDS REQUIREMENTS AT A GAS CENTRIFUGE ENRICHMENT FACILITY

    International Nuclear Information System (INIS)

    Gunning, John E.; Laughter, Mark D.; March-Leuba, Jose A.

    2008-01-01

    A number of countries have received construction licenses or are contemplating the construction of large-capacity gas centrifuge enrichment plants (GCEPs). The capability to independently verify nuclear material flows is a key component of international safeguards approaches, and the IAEA does not currently have an approved method to continuously monitor the mass flow of 235U in uranium hexafluoride (UF6) gas streams. Oak Ridge National Laboratory is investigating the development of a flow and enrichment monitor, or FEMO, based on an existing blend-down monitoring system (BDMS). The BDMS was designed to continuously monitor both 235U mass flow and enrichment of UF6 streams at the low pressures similar to those which exists at GCEPs. BDMSs have been installed at three sites-the first unit has operated successfully in an unattended environment for approximately 10 years. To be acceptable to GCEP operators, it is essential that the instrument be installed and maintained without interrupting operations. A means to continuously verify flow as is proposed by FEMO will likely be needed to monitor safeguards at large-capacity plants. This will enable the safeguards effectiveness that currently exists at smaller plants to be maintained at the larger facilities and also has the potential to reduce labor costs associated with inspections at current and future plants. This paper describes the FEMO design requirements, operating capabilities, and development work required before field demonstration.

  12. A Sulfur Trigger for the 2017 Phreatomagmatic Eruption of Poás Volcano, Costa Rica? Insights from MultiGAS and Drone-based Gas Monitoring

    Science.gov (United States)

    de Moor, M. J.; Aiuppa, A.; Avard, G.; Diaz, J. A.; Corrales, E.; Rüdiger, J.; D´Arcy, F.; Fischer, T. P.; Stix, J.; Alan, A.

    2017-12-01

    In April 2017 Poás volcano entered its first magmatic eruption period of the 21st century. The initial explosive blasts produced eruption columns up to 4 km in height, destroyed the pre-existing dome that was emplaced during the last magmatic eruption in the 1950s, and showered the tourist observation deck with bombs. Over the following months, the hyperacid crater lake dried out and a transition from phreatomagmatic to strombolian activity was observed. Two vents now dominate the activity. The main vent (old dome site) produces gas, ash, and scoria. A second vent is located in the dried-out lake bed and produces a peculiar canary-yellow gas plume. A fixed MultiGAS instrument installed in the crater bottom recorded large changes in gas composition prior to the explosive eruptions. The station recorded a dramatic increase in SO2/CO2 from an average of 0.04 for March 2017 to an average of 7.4 the day before the first explosive eruption that occurred at 18:30 on 12 April. A simultaneous rapid decrease in H2S/SO2 from 2.7 to drones, allowing continued gas monitoring despite dangerous conditions. Extremely high SO2/CO2 of 33 was measured with drone-based miniaturized MultiGAS ("miniGAS") in May 2017, and the ratio has since dropped to 3, which are more typical values of high temperature magmatic gases at Poás. The SO2 flux from Poás was at record low levels (Drone-based SO2 DOAS ("DROAS") measurements indicate high SO2 fluxes from Poas of >2000 T/d since the explosive eruptions, indicating a strong magmatic source and open conduits. We attribute the unusually S-rich gas compositions observed at Poás prior to and during the initial eruptions to combustion of previously deposited hydrothermal sulfur. The very low gas flux from the system prior to the explosive eruptions suggests that this sulfur may have played a role in hydrothermal sealing, leading to pressurization of the magmatic-hydrothermal system and ultimately triggering phreatomagmatic eruptions and "top down

  13. Application of end-tidal carbon dioxide monitoring via distal gas samples in ventilated neonates.

    Science.gov (United States)

    Jin, Ziying; Yang, Maoying; Lin, Ru; Huang, Wenfang; Wang, Jiangmei; Hu, Zhiyong; Shu, Qiang

    2017-08-01

    Previous research has suggested correlations between the end-tidal partial pressure of carbon dioxide (P ET CO 2 ) and the partial pressure of arterial carbon dioxide (PaCO 2 ) in mechanically ventilated patients, but both the relationship between P ET CO 2 and PaCO 2 and whether P ET CO 2 accurately reflects PaCO 2 in neonates and infants are still controversial. This study evaluated remote sampling of P ET CO 2 via an epidural catheter within an endotracheal tube to determine the procedure's clinical safety and efficacy in the perioperative management of neonates. Abdominal surgery was performed under general anesthesia in 86 full-term newborns (age 1-30 days, weight 2.55-4.0 kg, American Society of Anesthesiologists class I or II). The infants were divided into 2 groups (n = 43 each), and carbon dioxide (CO 2 ) gas samples were collected either from the conventional position (the proximal end) or a modified position (the distal end) of the epidural catheter. The P ET CO 2 measured with the new method was significantly higher than that measured with the traditional method, and the difference between P ET CO 2 and PaCO 2 was also reduced. The accuracy of P ET CO 2 measured increased from 78.7% to 91.5% when the modified sampling method was used. The moderate correlation between P ET CO 2 and PaCO 2 by traditional measurement was 0.596, which significantly increased to 0.960 in the modified sampling group. Thus, the P ET CO 2 value was closer to that of PaCO 2 . P ET CO 2 detected via modified carbon dioxide monitoring had a better accuracy and correlation with PaCO 2 in neonates. Copyright © 2017. Published by Elsevier B.V.

  14. Monitoring gas and heat emissions at Norris Geyser Basin, Yellowstone National Park, USA based on a combined eddy covariance and Multi-GAS approach

    Science.gov (United States)

    Lewicki, J. L.; Kelly, P. J.; Bergfeld, D.; Vaughan, R. G.; Lowenstern, J. B.

    2017-11-01

    .1, respectively, on average) were invariant during the measurement period and fell within the range of values measured in direct fumarole gas samples. The soil gas H2O/CO2 end member ratios ( 15-30) were variable and low relative to the fumarole end member, likely resulting from water vapor loss during cooling and condensation in the shallow subsurface, whereas the CO2/H2S end member ratio was high ( 160), presumably related to transport of CO2-dominated soil gas emissions mixed with trace fumarolic emissions to the Multi-GAS station. Nighttime eddy covariance ratios of H2O to CO2 flux were typically between the soil gas and fumarole end member H2O/CO2 ratios defined by Multi-GAS measurements. Overall, the combined eddy covariance and Multi-GAS approach provides a powerful tool for quasi-continuous measurements of gas and heat emissions for improved volcano-hydrothermal monitoring.

  15. Monitoring gas and heat emissions at Norris Geyser Basin, Yellowstone National Park, USA based on a combined eddy covariance and Multi-GAS approach

    Science.gov (United States)

    Lewicki, Jennifer L.; Kelly, Peter; Bergfeld, Deborah; Vaughan, R. Greg; Lowenstern, Jacob B.

    2017-01-01

    fumarole H2O/CO2 and CO2/H2S end member ratios (101.7 and 27.1, respectively, on average) were invariant during the measurement period and fell within the range of values measured in direct fumarole gas samples. The soil gas H2O/CO2end member ratios (~ 15–30) were variable and low relative to the fumarole end member, likely resulting from water vapor loss during cooling and condensation in the shallow subsurface, whereas the CO2/H2S end member ratio was high (~ 160), presumably related to transport of CO2-dominated soil gas emissions mixed with trace fumarolic emissions to the Multi-GAS station. Nighttime eddy covariance ratios of H2O to CO2 flux were typically between the soil gas and fumarole end member H2O/CO2 ratios defined by Multi-GAS measurements. Overall, the combined eddy covariance and Multi-GAS approach provides a powerful tool for quasi-continuous measurements of gas and heat emissions for improved volcano-hydrothermal monitoring.

  16. Joint interpretation of geoelectrical and soil-gas measurements for monitoring CO2 releases at a natural analogue

    DEFF Research Database (Denmark)

    Sauer, U.; Watanabe, N.; Singh, Ashok

    2014-01-01

    the complex behaviour of temporal variations for the flow patterns. In particular, coupled migration of gas and water plays an important influencing role in this process. Site-specific, near surface geological features and meteorological conditions seem to exert great influence on the degassing pattern...... and flux measurements, self-potential (SP) and geoelectrical surveys) showed that the combination of geophysical methods with soil-gas analysis for mesoscale monitoring of the shallow subsurface above geologic CO2 storages can be a valuable tool for mapping and monitoring potential CO2 spread...... in the subsurface. Three measurement campaigns were undertaken - May 2011, July 2011 and April 2012 - at an analogue site in the Cheb Basin, Czech Republic, with the aim of studying CO2 leakages and their temporal and spatial behaviour. Results of geoelectrical investigations give an insight into the structural...

  17. Turmoil at Turrialba volcano (Costa Rica): Degassing and eruptive behavior inferred from high-frequency gas monitoring

    OpenAIRE

    de Moor, J Maarten; Aiuppa, Alessandro; Avard, Geoffroy; Wehrmann, Heidi; Dunbar, Nelia W; Muller, Cyril; Tamburello, Giancarlo; Guidice, Gaetano; Liuzzo, Marco; Moretti, Roberto; Conde, A Vladimir; Galle, Bo

    2016-01-01

    Eruptive activity at Turrialba volcano (Costa Rica) has escalated significantly since 2014, causing airport and school closures in the capital city of San José. Whether or not new magma is involved in the current unrest seems probable but remains a matter of debate as ash deposits are dominated by hydrothermal material. Here, we use high frequency gas monitoring to track the behavior of the volcano between 2014 and 2015, and to decipher magmatic vs. hydrothermal contributions to the eruptions...

  18. A greenhouse-gas information system monitoring and validating emissions reporting and mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Jonietz, Karl K [Los Alamos National Laboratory; Dimotakis, Paul E [JPL/CAL TECH; Roman, Douglas A [LLNL; Walker, Bruce C [SNL

    2011-09-26

    Current GHG-mitigating regimes, whether internationally agreed or self-imposed, rely on the aggregation of self-reported data, with limited checks for consistency and accuracy, for monitoring. As nations commit to more stringent GHG emissions-mitigation actions and as economic rewards or penalties are attached to emission levels, self-reported data will require independent confirmation that they are accurate and reliable, if they are to provide the basis for critical choices and actions that may be required. Supporting emissions-mitigation efforts and agreements, as well as monitoring energy- and fossil-fuel intensive national and global activities would be best achieved by a process of: (1) monitoring of emissions and emission-mitigation actions, based, in part, on, (2) (self-) reporting of pertinent bottom-up inventory data, (3) verification that reported data derive from and are consistent with agreed-upon processes and procedures, and (4) validation that reported emissions and emissions-mitigation action data are correct, based on independent measurements (top-down) derived from a suite of sensors in space, air, land, and, possibly, sea, used to deduce and attribute anthropogenic emissions. These data would be assessed and used to deduce and attribute measured GHG concentrations to anthropogenic emissions, attributed geographically and, to the extent possible, by economic sector. The validation element is needed to provide independent assurance that emissions are in accord with reported values, and should be considered as an important addition to the accepted MRV process, leading to a MRV&V process. This study and report focus on attributes of a greenhouse-gas information system (GHGIS) needed to support MRV&V needs. These needs set the function of such a system apart from scientific/research monitoring of GHGs and carbon-cycle systems, and include (not exclusively): the need for a GHGIS that is operational, as required for decision-support; the need for a

  19. Evaluation of diffusive gradients in thin-films using a Diphonix{sup ®} resin for monitoring dissolved uranium in natural waters

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Geraldine S.C. [School of Earth and Environmental Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth, Hampshire PO1 3QL (United Kingdom); Mills, Graham A. [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St. Michael’s Building, White Swan Road, Portsmouth, Hampshire PO1 2DT (United Kingdom); Burnett, Jonathan L.; Amos, Sean [AWE Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom); Fones, Gary R., E-mail: gary.fones@port.ac.uk [School of Earth and Environmental Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth, Hampshire PO1 3QL (United Kingdom)

    2015-01-07

    Highlights: • Diphonix{sup ®} actinide specific resin was investigated for use with DGT to monitor U. • Uptake of U was unaffected by changes in aqueous pH, ionic strength, Ca{sup 2+} and CO{sub 3}{sup −}. • Diphonix{sup ®}-DGT can quantitatively measure U in fresh water over a 7 day deployment. • Matrix effects limited extended deployments in marine waters. • The device was able to measure precisely and accurately isotopic ratios of U. - Abstract: Commercially available Diphonix{sup ®} resin (TrisKem International) was evaluated as a receiving phase for use with the diffusive gradients in thin-films (DGT) passive sampler for measuring uranium. This resin has a high partition coefficient for actinides and is used in the nuclear industry. Other resins used as receiving phases with DGT for measuring uranium have been prone to saturation and significant chemical interferences. The performance of the device was evaluated in the laboratory and in field trials. In laboratory experiments uptake of uranium (all 100% efficiency) by the resin was unaffected by varying pH (4–9), ionic strength (0.01–1.00 M, as NaNO{sub 3}) and varying aqueous concentrations of Ca{sup 2+} (100–500 mg L{sup −1}) and HCO{sub 3}{sup −} (100–500 mg L{sup −1}). Due to the high partition coefficient of Diphonex{sup ®}, several elution techniques for uranium were evaluated. The optimal eluent mixture was 1 M NaOH/1 M H{sub 2}O{sub 2}, eluting 90% of the uranium from the resin. Uptake of uranium was linear (R{sup 2} = 0.99) over time (5 days) in laboratory experiments using artificial freshwater showing no saturation effects of the resin. In field deployments (River Lambourn, UK) the devices quantitatively accumulated uranium for up to 7 days. In both studies uptake of uranium matched that theoretically predicted for the DGT. Similar experiments in seawater did not follow the DGT theoretical uptake and the Diphonix{sup ®} appeared to be capacity limited and also affected

  20. Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases

    OpenAIRE

    Wei, Zhang; Simin, Li; Fengbing, Tang

    2013-01-01

    To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC) of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitr...

  1. Turmoil at Turrialba Volcano (Costa Rica): Degassing and eruptive processes inferred from high-frequency gas monitoring

    Science.gov (United States)

    de Moor, J. Maarten; Aiuppa, A.; Avard, G.; Wehrmann, H.; Dunbar, N.; Muller, C.; Tamburello, G.; Giudice, G.; Liuzzo, M.; Moretti, R.; Conde, V.; Galle, B.

    2016-08-01

    Eruptive activity at Turrialba Volcano (Costa Rica) has escalated significantly since 2014, causing airport and school closures in the capital city of San José. Whether or not new magma is involved in the current unrest seems probable but remains a matter of debate as ash deposits are dominated by hydrothermal material. Here we use high-frequency gas monitoring to track the behavior of the volcano between 2014 and 2015 and to decipher magmatic versus hydrothermal contributions to the eruptions. Pulses of deeply derived CO2-rich gas (CO2/Stotal > 4.5) precede explosive activity, providing a clear precursor to eruptive periods that occurs up to 2 weeks before eruptions, which are accompanied by shallowly derived sulfur-rich magmatic gas emissions. Degassing modeling suggests that the deep magmatic reservoir is 8-10 km deep, whereas the shallow magmatic gas source is at 3-5 km. Two cycles of degassing and eruption are observed, each attributed to pulses of magma ascending through the deep reservoir to shallow crustal levels. The magmatic degassing signals were overprinted by a fluid contribution from the shallow hydrothermal system, modifying the gas compositions, contributing volatiles to the emissions, and reflecting complex processes of scrubbing, displacement, and volatilization. H2S/SO2 varies over 2 orders of magnitude through the monitoring period and demonstrates that the first eruptive episode involved hydrothermal gases, whereas the second did not. Massive degassing (>3000 T/d SO2 and H2S/SO2 > 1) followed, suggesting boiling off of the hydrothermal system. The gas emissions show a remarkable shift to purely magmatic composition (H2S/SO2 < 0.05) during the second eruptive period, reflecting the depletion of the hydrothermal system or the establishment of high-temperature conduits bypassing remnant hydrothermal reservoirs, and the transition from phreatic to phreatomagmatic eruptive activity.

  2. Market monitor of the Dutch small-scale consumer market for electricity and natural gas. July 2006 - June 2007

    International Nuclear Information System (INIS)

    Van Liere, M.; Postema, B.; Te Velthuis, M.

    2009-01-01

    Every year the Dutch Competition Authority compiles a monitor report with the purpose of monitoring developments in the small consumers' markets for electricity and gas, identifying potential bottlenecks and providing recommendations for the enhancement of more efficient market power. This monitor report maps the market structure and market results of the small consumers' market. First, an overview is provided of a number of events that were in the news in the last year. Next chapters 1,2 and 3 (concentration, transparency and access thresholds) provide a description of the market structure in the small consumers' market. Chapters 4 up to and including 8 (prices, product range, services, switching and market confidence) address the market results [nl

  3. Measurements of the drift velocity using a small gas chamber for monitoring of the CMS muon system

    CERN Document Server

    Frangenheim, J

    This diploma thesis presents measurements of the drift velocity of electrons in gas. A small gas detector (VDC1 ) is used. This chamber is intended for measurement and monitoring of the drift velocity in the gas of the muon chambers of the gas detector system in the barrel area of the CMS-detector2 at the European Research Center for Particle Physics CERN near Geneva. The drift velocity is, together with the drift time, a key parameter for measurements with drift chambers. The aim of this thesis is to perform test measurements to determine parameters of the chamber and also to estimate systematic errors. Beside the drift velocity, further parameters of the gas like the pressure and the temperature are measured and accounted for. For the further work with the VDCs, analysis software has been created which is used for the analysis of the measurements. Parallel to this work, necessary improvements, e.g. for the high voltage robustness, were also implemented and tested. In addition, studies and test measurements ...

  4. Design of mini-multi-gas monitoring system based on IR absorption

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Q.L.; Zhang, W.D.; Xue, C.Y.; Xiong, J.J.; Ma, Y.C.; Wen, F. [Northern University of China, Taiyuan (China)

    2008-07-15

    In this paper, a novel non-dispersive infrared ray (IR) gas detection system is described. Conventional devices typically include several primary components: a broadband source (usually all incandescent filament), a rotating chopper shutter, a narrow-band filter, a sample tube and a detector. But we mainly use file mini-multi-channel detector, electrical modulation means and mini-gas-cell structure. To solve the problems of gas accidents in coal mines, and for family safety that results from using gas, this new IR detection system with integration, miniaturization and non-moving parts has been developed. It is based on the principle that certain gases absorb infrared radiation at specific (and often unique) wavelengths. The infrared detection optics principle used in developing this system is mainly analyzed. The idea of multi-gas detection is introduced and guided through the analysis of the single-gas detection. Through researching the design of cell structure, a cell with integration and miniaturization has been devised. By taking a single-chip microcomputer (SCM) as intelligence handling, the functional block diagram of a gas detection system is designed with the analyzing and devising of its hardware and software system. The way of data transmission on a controller area network (CAN) bus and wireless data transmission mode is explained. This system has reached the technology requirement of lower power consumption, mini-volume, wide measure range, and is able to realize multi-gas detection.

  5. Passive sampling and analyses of common dissolved fixed gases in groundwater

    International Nuclear Information System (INIS)

    Spalding, Brian Patrick; Watson, David B.

    2008-01-01

    An in situ passive sampler and gas chromatographic protocol for analysis of the major and several minor fixed gases in groundwater was developed. A gas-tight syringe, mated to a short length of silicone tubing, was equilibrated with dissolved gases in groundwater by immersing in monitoring wells and was used to transport and to inject a 0.5 mL gas sample into a gas chromatograph. Using Ar carrier gas, a HaySep DB porous polymer phase, and sequential thermal conductivity and reductive gas detectors allowed good sensitivity for He, Ne, H2, N2, O2, CO, CH4, CO2, and N2O. Within 4 days of immersion in groundwater, samplers initially filled with either He or air attained the same and constant gas composition at an Oak Ridge, Tennessee, site heavily impacted by uranium, acidity, and nitrate. Between June 2006 and July 2007, 12 permanent groundwater wells were used to test the passive samplers in groundwater contaminated by a group of four closed radioactive wastewater seepage ponds; over a thousand passive gas samples from these wells averaged 56% CO2, 32.4% N2, 2.5% O2, 2.5% N2O, 0.20% CH4, 0.096% H2, and 0.023% CO with an average recovery of 95 14% of the injected gas volume

  6. Radon gas monitoring survey for the determination of Radon Prone Areas in Lombardia

    Energy Technology Data Exchange (ETDEWEB)

    Bartolo, D. de; Alberici, A.; Gallini, R.; Maggioni, T.; Mondini, A.; Zini, E. [A.R.P.A. della Lombardia, Milano (Italy); Arrigoni, S.; Cazzaniga, P.; Cugini, A.; Gallinari, G.; Olivieri, F.; Romanelli, M. [A.R.P.A. della Lombardia, Dipt. di Bergamo, Bergamo (Italy)

    2006-07-01

    Region Lombardia has carried out a radon gas monitoring survey on its territory to localize radon prone areas as by law 241/00 enacted. To plan the survey, the Lombardia territory has been divided into two different types according to the morphology as well as the presence of a substratum of rock. The area with hills and mountains has been investigated with more attention compared to the plain because we can assume higher variability in radon concentration distribution due to the geological and morphological characteristics. The territory subdivision was based on the standard grid.. of the techniregional cartography (8 x 5 km). To perform radon indoor concentration measurements about 3600 measuring points were selected. They are located at the ground floor of buildings with the characteristics to ensure the tests are representative and comparable. It has also been taken into account evaluations done with previous surveys in accordance with the defined specification of the sites. The measurements were carried out using C.R. 39 trace detector technique. The detectors were contained in closed plastic canisters and they were positioned in situ for one year and measured each semester. The detectors were chemically treated and the traces counted using the automated optical system installed at the Radiometric Laboratory of the A.R.P.A. Department in Bergamo. The instrument accuracy and precision were evaluated using data obtained with different methods: using detectors exposed to radon known concentrations, participating to an international intercomparison as well as exposing the detector in a national calibration centre. Due to the large amount of detectors involved, a particular attention was taken for the detector homogeneity response and for the optimization of the analysis parameters. For further investigating the reliability of the measurements, two detectors were used in parallel in 10% of the tests. The results show higher values in the areas of Bergamo, Brescia

  7. National Coral Reef Monitoring Program: Dissolved inorganic carbon, total alkalinity, pH and other variables collected from surface discrete observations using infrared dissolved inorganic carbon analyzer, alkalinity titrator and other instruments from the North Atlantic Ocean near Key West, Florida (Class III climate monitoring sites) from 2012-03-23 to 2014-12-11 (NCEI Accession 0132022)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains data collected to monitor changes to coral reef carbonate chemistry over time, at US affiliated coral reef sites, through quantifying...

  8. Continuous Monitoring of CH4 Emissions from Marcellus Shale Gas Extraction in South West Pennsylvania Using Top Down Methodology

    Science.gov (United States)

    Sarmiento, D. P.; Belmecheri, S.; Lauvaux, T.; Sowers, T. A.; Bryant, S.; Miles, N. L.; Richardson, S.; Aikins, J.; Sweeney, C.; Petron, G.; Davis, K. J.

    2012-12-01

    Natural gas extraction from shale formations via hydraulic-fracturing (fracking) is expanding rapidly in several regions of North America. In Pennsylvania, the number of wells drilled to extract natural gas from the Marcellus shale has grown from 195 in 2008 to 1,386 in 2010. The gas extraction process using the fracking technology results in the escape of methane (CH4), a potent greenhouse gas and the principal component of natural gas, into the atmosphere. Emissions of methane from fracking operations remain poorly quantified, leading to a large range of scenarios for the contribution of fracking to climate change. A mobile measurement campaign provided insights on methane leakage rates and an improved understanding of the spatio-temporal variability in active drilling areas in the South West of Pennsylvania. Two towers were then instrumented to monitor fugitive emissions of methane from well pads, pipelines, and other infrastructures in the area. The towers, one within a drilling region and one upwind of active drilling, measured atmospheric CH4 mixing ratios continuously. Isotopic measurements from air flasks were also collected. Data from the initial mobile campaign were used to estimate emission rates from single sites such as wells and compressor stations. Tower data will be used to construct a simple atmospheric inversion for regional methane emissions. Our results show the daily variability in emissions and allow us to estimate leakage rates over a one month period in South West Pennsylvania. We discuss potential deployment strategies in drilling zones to monitor emissions of methane over longer periods of time.

  9. 78 FR 11619 - Greenhouse Gas Reporting Rule: Revision to Best Available Monitoring Method Request Submission...

    Science.gov (United States)

    2013-02-19

    ... protection, Administrative practice and procedures, Air pollution control, Greenhouse gases, Monitoring... Atmospheric Programs (MC-6207J), Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC...

  10. 78 FR 19605 - Greenhouse Gas Reporting Rule: Revision to Best Available Monitoring Method Request Submission...

    Science.gov (United States)

    2013-04-02

    ..., Administrative practice and procedures, Air pollution control, Greenhouse gases, Monitoring, Reporting and..., 2013. FOR FURTHER INFORMATION CONTACT: Carole Cook, Climate Change Division, Office of Atmospheric...

  11. BLM Colorado Oil & Gas Geophysical Permits (Dissolved)

    Data.gov (United States)

    Department of the Interior — KMZ File Format –This data is one feature type that is a part of a set consisting of six shapefiles pertaining to energy development and production in Colorado. The...

  12. BLM Colorado Oil and Gas Leases (Dissolved)

    Data.gov (United States)

    Department of the Interior — KMZ File Format –This data is one feature type that is a part of a set consisting of six shapefiles pertaining to energy development and production in Colorado. The...

  13. BLM Colorado Oil & Gas Geophysical Permits (Dissolved)

    Data.gov (United States)

    Department of the Interior — Shapefile Format –This data is one feature type that is a part of a set consisting of six shapefiles pertaining to energy development and production in Colorado. The...

  14. BLM Colorado Oil and Gas Units (Dissolve)

    Data.gov (United States)

    Department of the Interior — KMZ File Format –This data is one feature type that is a part of a set consisting of six shapefiles pertaining to energy development and production in Colorado. The...

  15. BLM Colorado Oil and Gas Leases (Dissolved)

    Data.gov (United States)

    Department of the Interior — Shapefile Format –This data is one feature type that is a part of a set consisting of six shapefiles pertaining to energy development and production in Colorado. The...

  16. BLM Colorado Oil and Gas Units (Dissolve)

    Data.gov (United States)

    Department of the Interior — Shapefile Format –This data is one feature type that is a part of a set consisting of six shapefiles pertaining to energy development and production in Colorado. The...

  17. A novel microbial fuel cell sensor with a gas diffusion biocathode sensing element for water and air quality monitoring.

    Science.gov (United States)

    Jiang, Yong; Liang, Peng; Huang, Xia; Ren, Zhiyong Jason

    2018-07-01

    Toxicity monitoring is essential for the protection of public health and ecological safety. Microbial fuel cell (MFC) sensors demonstrated good potential in toxicity monitoring, but current MFC sensors can only be used for anaerobic water monitoring. In this study, a novel gas diffusion (GD)-biocathode sensing element was fabricated using a simple method. The GD-biocathode MFC sensor can directly be used for formaldehyde detection (from 0.0005% to 0.005%) in both aerobic and anaerobic water bodies. Electrochemical analysis indicated that the response by the sensor was caused by the toxic inhibition to the microbial activity for the oxygen reduction reaction (ORR). This study for the first time demonstrated that the GD-biocathode MFC sensor has a detection limit of 20 ppm for formaldehyde and can be used to monitor air pollution. Selective sensitivity to formaldehyde was not achieved as the result of using a mixed-culture, which confirms that it can serve as a generic biosensor for monitoring gaseous pollutants. This study expands the realm of knowledge for MFC sensor applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Soil-gas monitoring: A tool for fault delineation studies along Hsinhua Fault (Tainan), Southern Taiwan

    International Nuclear Information System (INIS)

    Walia, Vivek; Lin, Shih Jung; Fu, Ching Chou; Yang, Tsanyao Frank; Hong, Wei-Li; Wen, Kuo-Liang; Chen, Cheng-Hong

    2010-01-01

    Many studies have shown the soil gas method to be one of the most reliable investigation tools in the research of earthquake precursory signals and fault delineation. The present research is aimed finding the relationship between soil gas distribution and tectonic systems in the vicinity of the Hsinhua Fault zone in the Tainan area of Southern Taiwan. More than 110 samples were collected along 13 traverses to find the spatial distribution of Rn, He, CO 2 and N 2 . The spatial congruence of all the gases shows that N 2 is the most probable carrier gas of He, whereas CO 2 seems to be a good carrier gas of Rn in this area. From the spatial distribution of Rn, He, CO 2 and N 2 the trace of Hsinhua Fault and neotectonic features can be identified. The spatial distribution of studied gases shows a clear anomalous trend ENE-SWS along the Hsinhua Fault.

  19. Infra-Red Gas Analysers of Liquid Crystal Type for Environmental Monitoring

    Directory of Open Access Journals (Sweden)

    V. I. Nazarov

    2004-01-01

    Full Text Available The paper reveals an opportunity to use infra-red gas analysers on the basis of the developed dichroic liquid crystal cells for investigation of absorption bands of various gases in the near infrared spectral region.

  20. Soil gas radon–thoron monitoring in Dharamsala area of north-west ...

    Indian Academy of Sciences (India)

    2National Center for Research on Earthquake Engineering, NARL, Taipei 106, Taiwan. ... The study described here is based on the measurements of soil gas radon–thoron concentrations performed ..... Himachal Pradesh, India; Nat. Hazards ...

  1. A gas monitoring facility with a quadrupole mass spectrometer for the ZEUS transition-radiation chambers

    International Nuclear Information System (INIS)

    Kapp, U.

    1988-07-01

    A gas analysis facility for the ZEUS transition-radiation chambers based on a quadrupole mass spectrometer is described. After a description of the spectrometer, the vacuum system, and the software, some test results are presented. (HSI)

  2. DGT measurement of dissolved aluminum species in waters

    DEFF Research Database (Denmark)

    Panther, Jared G.; Bennett, William W.; Teasdale, Peter R.

    2012-01-01

    Aluminum is acutely toxic, and elevated concentrations of dissolved Al can have detrimental effects on both terrestrial and aquatic ecosystems. Robust analytical methods that can determine environmentally relevant Al fractions accurately and efficiently are required by the environmental monitoring...

  3. Promising Data for Public Empowerment: The Making of Data Culture and Water Monitoring Infrastructures in the Marcellus Shale Gas Rush

    Science.gov (United States)

    Jalbert, Kirk

    A recent wave of advanced technologies for collecting and interpreting data offer new opportunities for laypeople to contribute to environmental monitoring science. This dissertation examines the conditions in which building knowledge infrastructures and embracing data "cultures" empowers and disempowers communities to challenge polluting industries. The processes and technologies of data cultures give people new capacities to understand their world, and to formulate powerful scientific arguments. However, data cultures also make many aspects of social life invisible, and elevate quantitative objective analysis over situated, subjective observation. This study finds that data cultures can empower communities when concerned citizens are equal contributors to research partnerships; ones that enable them to advocate for more nuanced data cultures permitting of structural critiques of status-quo environmental governance. These arguments are developed through an ethnographic study of participatory watershed monitoring projects that seek to document the impacts of shale gas extraction in Pennsylvania, New York, and West Virginia. Energy companies are drilling for natural gas using highly controversial methods of extraction known as hydraulic fracturing. Growing evidence suggests that nearby watersheds can be impacted by a myriad of extraction related problems including seepage from damaged gas well casing, improper waste disposal, trucking accidents, and the underground migration of hydraulic fracking fluids. In response to these risks, numerous organizations are coordinating and carrying out participatory water monitoring efforts. All of these projects embrace data culture in different ways. Each monitoring project has furthermore constructed its own unique infrastructure to support the sharing, aggregation, and analysis of environmental data. Differences in data culture investments and infrastructure building make some projects more effective than others in empowering

  4. Annual report on the Monitoring of good practices programs and independence for electricity and natural gas system operators - 2006

    International Nuclear Information System (INIS)

    2007-01-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 2. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2006. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2006 and audits carried out by the CRE services in these companies in 2006

  5. 2008 report on the Monitoring of good practices programs and independence for electricity and natural gas system operators

    International Nuclear Information System (INIS)

    2009-01-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 4. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2008. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2008 and audits carried out by the CRE services in these companies in 2008

  6. Annual report on the Monitoring of good practices programs and independence for electricity and natural gas system operators - 2007

    International Nuclear Information System (INIS)

    2008-01-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 3. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2007. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2007 and audits carried out by the CRE services in these companies in 2007

  7. Gas flushing through hyper-acidic crater lakes: the next steps within a reframed monitoring time window

    Science.gov (United States)

    Rouwet, Dmitri

    2016-04-01

    Tracking variations in the chemical composition, water temperature and pH of brines from peak-activity crater lakes is the most obvious way to forecast phreatic activity. Volcano monitoring intrinsically implies a time window of observation that should be synchronised with the kinetics of magmatic processes, such as degassing and magma intrusion. To decipher "how much time ago" a variation in degassing regime actually occurred before eventually being detected in a crater lake is key, and depends on the lake water residence time. The above reasoning assumes that gas is preserved as anions in the lake water (SO4, Cl, F anions), in other words, that scrubbing of acid gases is complete and irreversible. Less is true. Recent work has confirmed, by direct MultiGas measurement from evaporative plumes, that even the strongest acid in liquid medium (i.e. SO2) degasses from hyper-acidic crater lakes. The less strong acid HCl has long been recognised as being more volatile than hydrophyle in extremely acidic solutions (pH near 0), through a long-term steady increase in SO4/Cl ratios in the vigorously evaporating crater lake of Poás volcano. We now know that acidic gases flush through hyper-acidic crater lake brines, but we don't know to which extend (completely or partially?), and with which speed. The chemical composition hence only reflects a transient phase of the gas flushing through the lake. In terms of volcanic surveillance this brings the advantage that the monitoring time window is definitely shorter than defined by the water chemistry, but yet, we do not know how much shorter. Empirical experiments by Capaccioni et al. (in press) have tried to tackle this kinetic problem for HCl degassing from a "lab-lake" on the short-term (2 days). With this state of the art in mind, two new monitoring strategies can be proposed to seek for precursory signals of phreatic eruptions from crater lakes: (1) Tracking variations in gas compositions, fluxes and ratios between species in

  8. Ecological and economical efficiency of monitoring systems for oil and gas production on the shelf

    Science.gov (United States)

    Kurakin, A. L.; Lobkovsky, L. I.

    2014-02-01

    Requirements for signals' reliability of monitoring systems (with respect to the errors of the 1st and 2nd kinds, i.e., false alarms and skipping of danger) are deduced from the ratio of expenditures of different kinds (of exploitation expenses and losses due to accidents). The expressions obtained in the research may be used for economic foundations (and optimization) of specifications for monitoring systems. In cases when optimal parameters are not available, the sufficient condition of monitoring systems economical efficiency is presented.

  9. Investigation of sulphide in core drilled boreholes KLX06, KAS03 and KAS09 at Laxemar and Aespoe Chemical-, microbiological- and dissolved gas data from groundwater in four borehole sections

    Energy Technology Data Exchange (ETDEWEB)

    Rosdahl, Anette (Geosigma AB (Sweden)); Pedersen, Karsten; Hallbeck, Lotta (Microbial Analytics Sweden AB (Sweden)); Wallin, Bill (Geokema AB (Sweden))

    2011-01-15

    This report describes a study performed during 2009 which focused on the production of sulphide (microbial sulphate reduction) in deep groundwater that was implemented in the core drilled boreholes KLX06, -475 to 482 meter above sea level, m a s l, KAS03,-97 to 241 and -613 to 984 m a s l, and KAS09, -96 to -125 m a s l, at Laxemar and Aspo. The study aimed to increase knowledge of background groundwater levels of sulphide and its variations in time and space through the analysis of sulphide and parameters related to sulphide production. Sampling of groundwater was conducted in three core drilled boreholes of varying age as time series with continuous pumping and as single samples. The analysis program covered chemical parameters (pH, chloride, sulphate, iron, and organic carbon), dissolved gas composition, stable isotopes in groundwater (delta2H, delta18O, delta34S, delta13C), stable isotopes of gaseous compounds (delta2H, delta13C, delta18O), microbiological parameters (sulphate- and iron reducing bacteria, SRB and IRB), phthalates and low molecular mass organic acids (LMMOA). The sampling in KLX06 was carried out as time series with a 9 week pause in pumping. When the water volume discharged was about 150 times that of the packer-isolated borehole section, sulphides decreased from 7 mg L-1 to 0.05 mg L-1 and the salinity increased from 740 to 1,480 mg L-1. After a 9 weeks pause in pumping, the sulphide concentration and salinity again approached the original values, i.e. 7 mg L-1 of sulphide and 450 mg L-1 of chloride. The SRB and IRB showed high concentrations that were reduced during pumping in the borehole. The water in the standpipe which has a different water composition than the groundwater, also showed similar high concentrations of sulphide and SRB. The standpipe is a plastic pipe in the wider upper part of the borehole; connected with the tube from the packer of the borehole section and used to accommodate a filter and a groundwater pump when collecting

  10. Investigation of sulphide in core drilled boreholes KLX06, KAS03 and KAS09 at Laxemar and Aespoe: Chemical-, microbiological- and dissolved gas data from groundwater in four borehole sections

    International Nuclear Information System (INIS)

    Rosdahl, Anette; Pedersen, Karsten; Hallbeck, Lotta; Wallin, Bill

    2011-01-01

    This report describes a study performed during 2009 which focused on the production of sulphide (microbial sulphate reduction) in deep groundwater that was implemented in the core drilled boreholes KLX06, -475 to 482 meter above sea level, m a s l, KAS03,-97 to 241 and -613 to 984 m a s l, and KAS09, -96 to -125 m a s l, at Laxemar and Aspo. The study aimed to increase knowledge of background groundwater levels of sulphide and its variations in time and space through the analysis of sulphide and parameters related to sulphide production. Sampling of groundwater was conducted in three core drilled boreholes of varying age as time series with continuous pumping and as single samples. The analysis program covered chemical parameters (pH, chloride, sulphate, iron, and organic carbon), dissolved gas composition, stable isotopes in groundwater (δ 2 H, δ 18 O, δ 34 S, δ 13 C), stable isotopes of gaseous compounds (δ 2 H, δ 13 C, δ 18 O), microbiological parameters (sulphate- and iron reducing bacteria, SRB and IRB), phthalates and low molecular mass organic acids (LMMOA). The sampling in KLX06 was carried out as time series with a 9 week pause in pumping. When the water volume discharged was about 150 times that of the packer-isolated borehole section, sulphides decreased from 7 mg L -1 to 0.05 mg L -1 and the salinity increased from 740 to 1,480 mg L -1 . After a 9 weeks pause in pumping, the sulphide concentration and salinity again approached the original values, i.e. 7 mg L -1 of sulphide and 450 mg L -1 of chloride. The SRB and IRB showed high concentrations that were reduced during pumping in the borehole. The water in the standpipe which has a different water composition than the groundwater, also showed similar high concentrations of sulphide and SRB. The standpipe is a plastic pipe in the wider upper part of the borehole; connected with the tube from the packer of the borehole section and used to accommodate a filter and a groundwater pump when collecting

  11. Automatic semi-continuous accumulation chamber for diffuse gas emissions monitoring in volcanic and non-volcanic areas

    Science.gov (United States)

    Lelli, Matteo; Raco, Brunella; Norelli, Francesco; Virgili, Giorgio; Continanza, Davide

    2016-04-01

    Since various decades the accumulation chamber method is intensively used in monitoring activities of diffuse gas emissions in volcanic areas. Although some improvements have been performed in terms of sensitivity and reproducibility of the detectors, the equipment used for measurement of gas emissions temporal variation usually requires expensive and bulky equipment. The unit described in this work is a low cost, easy to install-and-manage instrument that will make possible the creation of low-cost monitoring networks. The Non-Dispersive Infrared detector used has a concentration range of 0-5% CO2, but the substitution with other detector (range 0-5000 ppm) is possible and very easy. Power supply unit has a 12V, 7Ah battery, which is recharged by a 35W solar panel (equipped with charge regulator). The control unit contains a custom programmed CPU and the remote transmission is assured by a GPRS modem. The chamber is activated by DataLogger unit, using a linear actuator between the closed position (sampling) and closed position (idle). A probe for the measure of soil temperature, soil electrical conductivity, soil volumetric water content, air pressure and air temperature is assembled on the device, which is already arranged for the connection of others external sensors, including an automatic weather station. The automatic station has been tested on the field at Lipari island (Sicily, Italy) during a period of three months, performing CO2 flux measurement (and also weather parameters), each 1 hour. The possibility to measure in semi-continuous mode, and at the same time, the gas fluxes from soil and many external parameters, helps the time series analysis aimed to the identification of gas flux anomalies due to variations in deep system (e.g. onset of volcanic crises) from those triggered by external conditions.

  12. Monitoring the Wobbe Index of Natural Gas Using Fiber-Enhanced Raman Spectroscopy

    Directory of Open Access Journals (Sweden)

    Vincenz Sandfort

    2017-11-01

    Full Text Available The fast and reliable analysis of the natural gas composition requires the simultaneous quantification of numerous gaseous components. To this end, fiber-enhanced Raman spectroscopy is a powerful tool to detect most components in a single measurement using a single laser source. However, practical issues such as detection limit, gas exchange time and background Raman signals from the fiber material still pose obstacles to utilizing the scheme in real-world settings. This paper compares the performance of two types of hollow-core photonic crystal fiber (PCF, namely photonic bandgap PCF and kagomé-style PCF, and assesses their potential for online determination of the Wobbe index. In contrast to bandgap PCF, kagomé-PCF allows for reliable detection of Raman-scattered photons even below 1200 cm−1, which in turn enables fast and comprehensive assessment of the natural gas quality of arbitrary mixtures.

  13. Monitoring the Wobbe Index of Natural Gas Using Fiber-Enhanced Raman Spectroscopy.

    Science.gov (United States)

    Sandfort, Vincenz; Trabold, Barbara M; Abdolvand, Amir; Bolwien, Carsten; Russell, Philip St. J; Wöllenstein, Jürgen; Palzer, Stefan

    2017-11-24

    The fast and reliable analysis of the natural gas composition requires the simultaneous quantification of numerous gaseous components. To this end, fiber-enhanced Raman spectroscopy is a powerful tool to detect most components in a single measurement using a single laser source. However, practical issues such as detection limit, gas exchange time and background Raman signals from the fiber material still pose obstacles to utilizing the scheme in real-world settings. This paper compares the performance of two types of hollow-core photonic crystal fiber (PCF), namely photonic bandgap PCF and kagomé-style PCF, and assesses their potential for online determination of the Wobbe index. In contrast to bandgap PCF, kagomé-PCF allows for reliable detection of Raman-scattered photons even below 1200 cm -1 , which in turn enables fast and comprehensive assessment of the natural gas quality of arbitrary mixtures.

  14. Low-cost, portable open-source gas monitoring device based on chemosensory technology

    International Nuclear Information System (INIS)

    Gotor, Raúl; Gaviña, Pablo; Costero, Ana M

    2015-01-01

    We report herein the construction of an electronic device to perform the real-time digitalization of the color state of the optical chemosensors used in the detection of dangerous gases. To construct the device, we used open-source modular electronics, such as Arduino and Sparkfun components, as well as free and open-source software (FOSS). The basic principle of the operation of this device is the continuous color measurement of a chemosensor-doped sensing film, whose color changes in the presence of a specific gas. The chemosensor-sensing film can be prepared by using any of the widely available chemosensors for the desired gas. Color measurement is taken by two TCS230 color sensor ICs, reported to the microcontroller, and the results are displayed on an LCD display and pushed through a USB serial port. By using a cyanide optical chemosensor, we demonstrated the operation of the device as a HCN gas detector at low concentrations. (paper)

  15. From the Lab to the real world : sources of error in UF {sub 6} gas enrichment monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Lombardi, Marcie L.

    2012-03-01

    Safeguarding uranium enrichment facilities is a serious concern for the International Atomic Energy Agency (IAEA). Safeguards methods have changed over the years, most recently switching to an improved safeguards model that calls for new technologies to help keep up with the increasing size and complexity of today’s gas centrifuge enrichment plants (GCEPs). One of the primary goals of the IAEA is to detect the production of uranium at levels greater than those an enrichment facility may have declared. In order to accomplish this goal, new enrichment monitors need to be as accurate as possible. This dissertation will look at the Advanced Enrichment Monitor (AEM), a new enrichment monitor designed at Los Alamos National Laboratory. Specifically explored are various factors that could potentially contribute to errors in a final enrichment determination delivered by the AEM. There are many factors that can cause errors in the determination of uranium hexafluoride (UF{sub 6}) gas enrichment, especially during the period when the enrichment is being measured in an operating GCEP. To measure enrichment using the AEM, a passive 186-keV (kiloelectronvolt) measurement is used to determine the {sup 235}U content in the gas, and a transmission measurement or a gas pressure reading is used to determine the total uranium content. A transmission spectrum is generated using an x-ray tube and a “notch” filter. In this dissertation, changes that could occur in the detection efficiency and the transmission errors that could result from variations in pipe-wall thickness will be explored. Additional factors that could contribute to errors in enrichment measurement will also be examined, including changes in the gas pressure, ambient and UF{sub 6} temperature, instrumental errors, and the effects of uranium deposits on the inside of the pipe walls will be considered. The sensitivity of the enrichment calculation to these various parameters will then be evaluated. Previously, UF

  16. Monitoring of volatile organic compounds (VOCs) from an oil and gas station in northwest China for 1 year

    Science.gov (United States)

    Zheng, Huang; Kong, Shaofei; Xing, Xinli; Mao, Yao; Hu, Tianpeng; Ding, Yang; Li, Gang; Liu, Dantong; Li, Shuanglin; Qi, Shihua

    2018-04-01

    Oil and natural gas are important for energy supply around the world. The exploring, drilling, transportation and processing in oil and gas regions can release a lot of volatile organic compounds (VOCs). To understand the VOC levels, compositions and sources in such regions, an oil and gas station in northwest China was chosen as the research site and 57 VOCs designated as the photochemical precursors were continuously measured for an entire year (September 2014-August 2015) using an online monitoring system. The average concentration of total VOCs was 297 ± 372 ppbv and the main contributor was alkanes, accounting for 87.5 % of the total VOCs. According to the propylene-equivalent concentration and maximum incremental reactivity methods, alkanes were identified as the most important VOC groups for the ozone formation potential. Positive matrix factorization (PMF) analysis showed that the annual average contributions from natural gas, fuel evaporation, combustion sources, oil refining processes and asphalt (anthropogenic and natural sources) to the total VOCs were 62.6 ± 3.04, 21.5 ± .99, 10.9 ± 1.57, 3.8 ± 0.50 and 1.3 ± 0.69 %, respectively. The five identified VOC sources exhibited various diurnal patterns due to their different emission patterns and the impact of meteorological parameters. Potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) models based on backward trajectory analysis indicated that the five identified sources had similar geographic origins. Raster analysis based on CWT analysis indicated that the local emissions contributed 48.4-74.6 % to the total VOCs. Based on the high-resolution observation data, this study clearly described and analyzed the temporal variation in VOC emission characteristics at a typical oil and gas field, which exhibited different VOC levels, compositions and origins compared with those in urban and industrial areas.

  17. Monitoring the behaviour of 4-ketocyclophosphamide versus cyclophosphamide during capillary gas chromatography by mass spectrometry

    NARCIS (Netherlands)

    Bruijn, de E.A.; Oosterom, van A.T.; Leclercq, P.A.; Haan, de J.W.; Ven, van de L.J.M.; Tjaden, U.R.

    1987-01-01

    Capillary Gas Chromatography (CGC) is capable of determining underivatized cyclophosphamide (CPA) using SCOT OV 275 columns. Then CPA is subjected to in situ degradation resulting in formation of a cyclization product which can be determined selectively in biological fluids. In routine bioanalysis

  18. Measuring the respiratory gas exchange of grazing cattle using the GreenFeed emissions monitoring system

    Science.gov (United States)

    Ruminants are a significant source of enteric methane, which has been identified as a powerful greenhouse gas that contributes to climate change. With interest in developing technologies to decrease enteric methane emission, systems are currently being developed to measure the methane emission by c...

  19. Continuous monitoring of methyl iodide purity and content in the gas feeding the trapping pilot plant

    International Nuclear Information System (INIS)

    Charrier, G.

    1988-01-01

    An analysis method is developed for inspection of solid traps for gaseous iodine. Methyl iodide injected in the traps is determined by gas chromatography. Contents of 50 ppm in volume are measured. Labelling with iodine 123 allows a better sensitivity, 4 refs, 5 figs, 6 tables [fr

  20. Calibration of a large volume argon-41 gas-effluent monitor

    International Nuclear Information System (INIS)

    Wilson, William E.; Lovas, Thomas A.

    1976-01-01

    In September of 1975, a large volume Argon-41 sampler was calibrated using a series connected calibration chamber of known sensitivity and a constant flow of activated Argon gas. The calibration included analysis of the effects of flow rate through the large volume sampler and yielded a calibration constant of 2.34 x 10 -8 μc/cm 3 /CPM. (author)

  1. Mobile hybrid LiDAR & infrared sensing for natural gas pipeline monitoring, final report.

    Science.gov (United States)

    2016-01-01

    The natural gas distribution system in the U.S. has a total of 1.2 million miles of mains and about 65 million service lines as of 2012 [1]. This distribution system consists of various material types and is subjected to various threats which vary ac...

  2. Utilization of on-line corrosion monitoring in the flue gas cleaning system

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Nielsen, Lars V.; Petersen, Michael B.

    2015-01-01

    fan. The corrosion rates measured with respect to time were correlated to plant data such as load, temperature, gas composition, water content as well as change in the fuel used. From these results it is clear that many shutdowns/start-ups influence corrosion and therefore cause decreased lifetime...

  3. Soil-gas monitoring: A tool for fault delineation studies along Hsinhua Fault (Tainan), Southern Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Walia, Vivek, E-mail: vivekwalia@rediffmail.com [National Center for Research on Earthquake Engineering, National Applied Research Laboratories, Taipei 106, Taiwan (China); Lin, Shih Jung [National Center for Research on Earthquake Engineering, National Applied Research Laboratories, Taipei 106, Taiwan (China); Fu, Ching Chou; Yang, Tsanyao Frank; Hong, Wei-Li [Department of Geosciences, National Taiwan University, Taipei 106, Taiwan (China); Wen, Kuo-Liang [National Center for Research on Earthquake Engineering, National Applied Research Laboratories, Taipei 106, Taiwan (China)] [Department of Earth Sciences and Institute of Geophysics, National Central University, Jhongli 32054, Taiwan (China); Chen, Cheng-Hong [Department of Geosciences, National Taiwan University, Taipei 106, Taiwan (China)

    2010-04-15

    Many studies have shown the soil gas method to be one of the most reliable investigation tools in the research of earthquake precursory signals and fault delineation. The present research is aimed finding the relationship between soil gas distribution and tectonic systems in the vicinity of the Hsinhua Fault zone in the Tainan area of Southern Taiwan. More than 110 samples were collected along 13 traverses to find the spatial distribution of Rn, He, CO{sub 2} and N{sub 2}. The spatial congruence of all the gases shows that N{sub 2} is the most probable carrier gas of He, whereas CO{sub 2} seems to be a good carrier gas of Rn in this area. From the spatial distribution of Rn, He, CO{sub 2} and N{sub 2} the trace of Hsinhua Fault and neotectonic features can be identified. The spatial distribution of studied gases shows a clear anomalous trend ENE-SWS along the Hsinhua Fault.

  4. RFID reader with gas sensing capability for monitoring fruit along the logistic chain: array development and signal processing

    Science.gov (United States)

    Llobet, Eduard; Vergara, Alexander; Ramírez, José Luis; Zampolli, Stefano; Becker, Thomas; Fonseca, Luis

    2007-05-01

    The reliable and low-cost quantitative detection of ethylene for food/fruit applications remains an unsolved problem. Existing commercial systems are able to quantify ethylene (at sub ppm levels) but either they are off-line: require periodic sample collection and use of reagents or high-cost. We will report on the development of an RFID reader with onboard micro-machined metal oxide gas sensors aimed at monitoring climacteric fruit during transport and vending. The developed platform integrates a commercial off the shelf inductive coupling RF transceiver in the 13.56MHz band, fully compliant with the ISO15693 standard, micro-hotplate gas sensors, driving and readout electronics. If the sensors are operated at a fixed temperature, the reader could work as an alarm level monitor able to assess the conservation stage of apples. On the other hand, when the sensors are operated under an optimised temperature-modulation mode, accurate calibration models for the species that are relevant to assess the conservation stage of apples (i.e., ethylene, acetaldehyde and ethanol) can be built. Finally, different feature extraction techniques such as the FFT and the Energy Vector will be used in combination with pattern recognition tools like PLS and PLS-DA to show that our system is able to identify and quantify the species that are relevant for the application considered.

  5. International Energy Agency (IEA) Greenhouse Gas (GHG) Weyburn-Midale CO₂ Monitoring and Storage Project

    Energy Technology Data Exchange (ETDEWEB)

    Sacuta, Norm [Petroleum Technology Research Centre Incorporated, Saskatchewan (Canada); Young, Aleana [Petroleum Technology Research Centre Incorporated, Saskatchewan (Canada); Worth, Kyle [Petroleum Technology Research Centre Incorporated, Saskatchewan (Canada)

    2015-12-22

    The IEAGHG Weyburn-Midale CO₂ Monitoring and Storage Project (WMP) began in 2000 with the first four years of research that confirmed the suitability of the containment complex of the Weyburn oil field in southeastern Saskatchewan as a storage location for CO₂ injected as part of enhanced oil recovery (EOR) operations. The first half of this report covers research conducted from 2010 to 2012, under the funding of the United States Department of Energy (contract DEFE0002697), the Government of Canada, and various other governmental and industry sponsors. The work includes more in-depth analysis of various components of a measurement, monitoring and verification (MMV) program through investigation of data on site characterization and geological integrity, wellbore integrity, storage monitoring (geophysical and geochemical), and performance/risk assessment. These results then led to the development of a Best Practices Manual (BPM) providing oilfield and project operators with guidance on CO₂ storage and CO₂-EOR. In 2013, the USDOE and Government of Saskatchewan exercised an optional phase of the same project to further develop and deploy applied research tools, technologies, and methodologies to the data and research at Weyburn with the aim of assisting regulators and operators in transitioning CO₂-EOR operations into permanent storage. This work, detailed in the second half of this report, involves seven targeted research projects – evaluating the minimum dataset for confirming secure storage; additional overburden monitoring; passive seismic monitoring; history-matched modelling; developing proper wellbore design; casing corrosion evaluation; and assessment of post CO₂-injected core samples. The results from the final and optional phases of the Weyburn-Midale Project confirm the suitability of CO₂-EOR fields for the injection of CO₂, and further, highlight the necessary MMV and follow-up monitoring required for these operations to be considered

  6. Detection of hydrogen dissolved in acrylonitrile butadiene rubber by 1H nuclear magnetic resonance

    Science.gov (United States)

    Nishimura, Shin; Fujiwara, Hirotada

    2012-01-01

    Rubber materials, which are used for hydrogen gas seal, can dissolve hydrogen during exposure in high-pressure hydrogen gas. Dissolved hydrogen molecules were detected by solid state 1H NMR of the unfilled vulcanized acrylonitrile butadiene rubber. Two signals were observed at 4.5 ppm and 4.8 ppm, which were assignable to dissolved hydrogen, in the 1H NMR spectrum of NBR after being exposed 100 MPa hydrogen gas for 24 h at room temperature. These signals were shifted from that of gaseous hydrogen molecules. Assignment of the signals was confirmed by quantitative estimation of dissolved hydrogen and peak area of the signals.

  7. Evaluation of the Electronic Bubbler Gas Monitoring System for High Flow in the BaBar Detector

    International Nuclear Information System (INIS)

    Little, Angela

    2003-01-01

    We evaluated the gas monitoring system in the Instrumented Flux Return (IFR) portion of the BaBar detector at the Stanford Linear Accelerator Center (SLAC) to determine its suitability for flows greater than 80 cc/min. Future modifications to the IFR involve particle detectors with a higher gas flow rate than currently in use. Therefore, the bubbler system was tested to determine if it can handle high flow rates. Flow rates between 80 and 240 cc/min were analyzed through short term calibration and long term stability tests. The bubbler system was found to be reliable for flow rates between 80 and 160 cc/min. For flow rates between 200 and 240 cc/min, electronic instabilities known as baseline spikes caused a 10-20% error in the bubble rate. An upgrade would be recommended for use of the bubbler system at these flow rates. Since the planned changes in the IFR will require a maximum flow of 150 cc/min, the bubbler system can sufficiently handle the new gas flow rates

  8. NOx Monitoring in Humid Exhaust Gas Using Non-Dispersive Infrared Spectroscopy

    DEFF Research Database (Denmark)

    Stolberg-Rohr, Thomine Kirstine

    This PhD thesis is concerned with the measurement of NOX in moist exhaust gas onboard ships using non-dispersive infrared (NDIR) spectroscopy. In such a measurement one of the major challenges is spectral interference from water vapour which is present in high concentrations in the exhaust. The Ph......D study investigates a possible solution to this problem, which is to balance out the signal contribution from water vapour by means of carefully designed and manufactured optical bandpass filters. The thesis, presents a thorough theoretical description of the NDIR sensor concept together with simulations...... suggesting that it is possible but challenging to measure NOX in moist exhaust gas using NDIR. The characteristics of optical filters tend to change with temperature, and since this compromises the water signal balancing, much of the work presented in the thesis is devoted to the design of optical bandpass...

  9. Infrared thermography inspection and monitoring in oil and gas and petrochemical plant industry

    International Nuclear Information System (INIS)

    Shamsudin Sin Deraman

    2003-01-01

    Infrared thermography is an electronic technique that quite literally allows us to see thermal energy. The technique allows for the monitoring of temperatures and thermal patterns while the equipment is online and running under full load. Armed with guidelines of allowable operating temperature limits of the equipment, the technique may enhances company's, ?ability to predict equipment failure and plan corrective action before a costly shutdown, equipment damage, or personal injury occurs. Infrared thermography is an excellent condition monitoring tool to assist in the reduction of maintenance costs on mechanical, electrical and equipment. With this new capability plant maintenance personnel have recognized infrared thermography as one of the most versatile and effective condition monitoring tools available today. Infrared can be used on a wide variety of equipment including pumps, motors, bearings, pulleys, fans, drives, conveyors etc. This paper will explain the benefits of Infrared Thermography as a condition monitoring tool for plant equipment and mechanical systems and some examples of infrared thermography application is discussed. (Author)

  10. Backfitting of existing nuclear power plants with particulate, iodine and noble gas monitors

    International Nuclear Information System (INIS)

    Marley, M.R.; Geiger, E.L.

    1978-01-01

    A stand-alone microcomputer complete with hardware and software to measure airborne particulate iodine and noble gases is described. This system meets the need at power plants and effluent monitoring. The equipment will accommodate up to 192 channels of input

  11. Design, development and calibration of a radioactive gas (85Kr) detector for continuous environmental monitoring

    International Nuclear Information System (INIS)

    Janardhanan, S.; Swaminathan, N.; John, Jacob; Kutty, K.N.; Wattamwar, S.B.; Gopalan, C.S.; Menezes, C.M.

    1982-01-01

    Design, development and calibration of a scintillation type detector for environmental monitoring of low levels of 85 Kr activity in off-line effluents or plant areas in presence of gamma background are reported. Calibration of the system was done using NBS 85 Kr standard. (author)

  12. Design, development and calibration of a radioactive gas (/sup 85/Kr) detector for continuous environmental monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Janardhanan, S.; Swaminathan, N.; John, J.; Kutty, K.N.; Wattamwar, S.B. (Bhabha Atomic Research Centre, Bombay (India). Health Physics Div.); Gopalan, C.S.; Menezes, C.M. (Bhabha Atomic Research Centre, Bombay (India). Electronics Div.)

    Design, development and calibration of a scintillation type detector for environmental monitoring of low levels of /sup 85/Kr activity in off-line effluents or plant areas in presence of gamma background are reported. Calibration of the system was done using NBS /sup 85/Kr standard.

  13. Method to Estimate the Dissolved Air Content in Hydraulic Fluid

    Science.gov (United States)

    Hauser, Daniel M.

    2011-01-01

    In order to verify the air content in hydraulic fluid, an instrument was needed to measure the dissolved air content before the fluid was loaded into the system. The instrument also needed to measure the dissolved air content in situ and in real time during the de-aeration process. The current methods used to measure the dissolved air content require the fluid to be drawn from the hydraulic system, and additional offline laboratory processing time is involved. During laboratory processing, there is a potential for contamination to occur, especially when subsaturated fluid is to be analyzed. A new method measures the amount of dissolved air in hydraulic fluid through the use of a dissolved oxygen meter. The device measures the dissolved air content through an in situ, real-time process that requires no additional offline laboratory processing time. The method utilizes an instrument that measures the partial pressure of oxygen in the hydraulic fluid. By using a standardized calculation procedure that relates the oxygen partial pressure to the volume of dissolved air in solution, the dissolved air content is estimated. The technique employs luminescent quenching technology to determine the partial pressure of oxygen in the hydraulic fluid. An estimated Henry s law coefficient for oxygen and nitrogen in hydraulic fluid is calculated using a standard method to estimate the solubility of gases in lubricants. The amount of dissolved oxygen in the hydraulic fluid is estimated using the Henry s solubility coefficient and the measured partial pressure of oxygen in solution. The amount of dissolved nitrogen that is in solution is estimated by assuming that the ratio of dissolved nitrogen to dissolved oxygen is equal to the ratio of the gas solubility of nitrogen to oxygen at atmospheric pressure and temperature. The technique was performed at atmospheric pressure and room temperature. The technique could be theoretically carried out at higher pressures and elevated

  14. Comparison of use of an infrared anesthetic gas monitor and refractometry for measurement of anesthetic agent concentrations.

    Science.gov (United States)

    Ambrisko, Tamas D; Klide, Alan M

    2011-10-01

    To assess agreement between anesthetic agent concentrations measured by use of an infrared anesthetic gas monitor (IAGM) and refractometry. SAMPLE-4 IAGMs of the same type and 1 refractometer. Mixtures of oxygen and isoflurane, sevoflurane, desflurane, or N(2)O were used. Agent volume percent was measured simultaneously with 4 IAGMs and a refractometer at the common gas outlet. Measurements obtained with each of the 4 IAGMs were compared with the corresponding refractometer measurements via the Bland-Altman method. Similarly, Bland-Altman plots were also created with either IAGM or refractometer measurements and desflurane vaporizer dial settings. Bias ± 2 SD for comparisons of IAGM and refractometer measurements was as follows: isoflurane, -0.03 ± 0.18 volume percent; sevoflurane, -0.19 ± 0.23 volume percent; desflurane, 0.43 ± 1.22 volume percent; and N(2)O, -0.21 ± 1.88 volume percent. Bland-Altman plots comparing IAGM and refractometer measurements revealed nonlinear relationships for sevoflurane, desflurane, and N(2)O. Desflurane measurements were notably affected; bias ± limits of agreement (2 SD) were small (0.1 ± 0.22 volume percent) at < 12 volume percent, but both bias and limits of agreement increased at higher concentrations. Because IAGM measurements did not but refractometer measurements did agree with the desflurane vaporizer dial settings, infrared measurement technology was a suspected cause of the nonlinear relationships. Given that the assumption of linearity is a cornerstone of anesthetic monitor calibration, this assumption should be confirmed before anesthetic monitors are used in experiments.

  15. Increasing operations profitability using an end-to-end, wireless internet, gas monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, M. [Northrock Resources Ltd., AB (Canada); Benterud, K. [zed.i solutions, inc., Calgary, AB (Canada)

    2004-10-01

    Implementation by Northrock Resources Ltd., a wholly-owned subsidiary of Unocal Corporation, of a fully integrated end-to-end gas measurement and production analysis system, is discussed. The system, dubbed Smart-Alek(TM), utilizes public wireless communications and a web browser only delivery system to provide seamless well visibility to a desk-top computer. Smart-Alek(TM) is an example of a new type of end-to-end electronic gas flow measurement system, known as FINE(TM), which is an acronym for Field Intelligence Network and End-User Interface. The system delivers easy-to-use, complete, reliable and cost effective production information, far more effective than is possible to obtain with conventional SCADA technology. By installing the system, Northrock was able to increase gas volumes with more accurate electronic flow measurement in place of mechanical charts, with very low technical maintenance, and at a reduced operating cost. It is emphasized that deploying the technology alone will produce only partial benefits; to realize full benefits it is also essential to change grass roots operating practices, aiming at timely decision-making at the field level. 5 refs., 5 figs.

  16. Performance and optimization of a combustion interface for isotope ratio monitoring gas chromatography/mass spectrometry

    Science.gov (United States)

    Merritt, D. A.; Freeman, K. H.; Ricci, M. P.; Studley, S. A.; Hayes, J. M.

    1995-01-01

    Conditions and systems for on-line combustion of effluents from capillary gas chromatographic columns and for removal of water vapor from product streams were tested. Organic carbon in gas chromatographic peaks 15 s wide and containing up to 30 nanomoles of carbon was quantitatively converted to CO2 by tubular combustion reactors, 200 x 0.5 mm, packed with CuO or NiO. No auxiliary source of O2 was required because oxygen was supplied by metal oxides. Spontaneous degradation of CuO limited the life of CuO reactors at T > 850 degrees C. Since NiO does not spontaneously degrade, its use might be favored, but Ni-bound carbon phases form and lead to inaccurate isotopic results at T Water must be removed from the gas stream transmitted to the mass spectrometer or else protonation of CO2 will lead to inaccuracy in isotopic analyses. Although thresholds for this effect vary between mass spectrometers, differential permeation of H2O through Nafion tubing was effective in both cases tested, but the required length of the Nafion membrane was 4 times greater for the more sensitive mass spectrometer.

  17. Monitoring of good practices programs and independence for electricity and natural gas system operators. Summary report 2011

    International Nuclear Information System (INIS)

    2012-07-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 7. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2011. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2011 and audits carried out by the CRE services in these companies in 2011. These elements were supplemented and clarified by many exchanges with the operators, in particular during the committee hearings that took place in spring 2012 with each network operator. This report is structured around four cross-cutting themes, supplemented by individual analyses of each operator's situation. The cross-cutting issues address communication and user's awareness of the network operators, the new compliance officer function, TSO certification and, finally, the results of the 'mystery shopper' telephone survey carried out by the CRE. The individual situations analysed were those of the eight DSOs serving over 100,000 customers (ERDF, ES, URM, SRD and Geredis-Deux-Sevres for electricity, GrDF, Regaz-Bordeaux and Reseau GDS for natural gas) and the three TSOs (RTE for electricity and GRTgaz and TIGF for natural gas)

  18. Nonintrusive gas monitoring in neonatal lungs using diode laser spectroscopy: feasibility study.

    Science.gov (United States)

    Lewander, Märta; Bruzelius, Anders; Svanberg, Sune; Svanberg, Katarina; Fellman, Vineta

    2011-12-01

    A feasibility study on noninvasive, real-time monitoring of gases in lungs of preterm infants is reported, where a laser-spectroscopic technique using diode lasers tuned to oxygen and water vapor absorption lines was employed on realistic tissue phantoms. Our work suggests that the technique could provide a new possibility for surveillance of the lung function of preterm infants, in particular the oxygenation, which is of prime importance in this patient group.

  19. Development and Evaluation of a Hyperbaric Toxic Gas Monitor (SubTox) for Disabled Submarines

    Science.gov (United States)

    2013-08-01

    air near the CO2 scrubbers was sampled, the common amine/ ammonia smell was present. And while no NH3 sensor was installed in the SubTox, no monitored...under pressure, the eight gases — ammonia , carbon monoxide, chlorine, hydrogen chloride, hydrogen cyanide, hydrogen sulfide, nitrogen dioxide, and...gases for which SEALs have been defined: ammonia (NH3), carbon monoxide (CO), chlorine (Cl2), hydrogen chloride (HCl), hydrogen cyanide (HCN

  20. [Research on lateral shearing interferometer for field monitoring of natural gas pipeline leak].

    Science.gov (United States)

    Zhang, Xue-Feng; Gao, Yu-Bin

    2012-09-01

    Aimed at the mechanical scanning spectroscopy equipment with poor anti-interference and anti-jamming ability, which affects the accuracy of its natural gas pipeline leak detection in the wild, a new type of lateral shearing interferometer system was designed. The system uses a beam splitter to get optical path difference by a mechanical scanning part, and it cancel the introduction of external vibration interference through the linkage between the two beam splitterw. The interference intensity of interference fringes produced was calculated, and analysis of a rotating beam splitter corresponds to the angle of the optical path difference function, solving for the maximum angle of the forward rotation and reverse rotation, which is the maximum optical path range. Experiments using the gas tank deflated simulated natural gas pipeline leak process, in the interference conditions, and the test data of the type WQF530 spectrometer and the new type of lateral shearing interferometer system were comparedt. The experimental results show that the relative error of both systems is about 1% in indoor conditions without interference. However, in interference environment, the error of WQF530 type spectrometer becomes larger, more than 10%, but the error of the new type of lateral shearing interferometer system is still below 5%. The detection accuracy of the type WQF530 spectrometer decreased significantly due to the environment. Therefore, the seismic design of the system can effectively offset power deviation and half-width increases of center wavelength caused by external interference, and compared to conventional mechanical scanning interferometer devices the new system is more suitable for field detection.

  1. Diagnostic monitoring of the condition of the amplification-transformer channel of automatic gas protection apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Karpov, Ye F; Basovskiy, B I; Popov, V V

    1978-01-01

    A method is suggested for verifying the performance capacity of an amplifier-transformer channel of apparatus for automatic gas protection under operating conditions. Processes are examined which occur in the bridge measurement plan of the sensor during shunting of one of the thermal-transformer elements by a resistor. An expression is obtained for determining the coefficient of transfer of the amplification-transformer channel on the outlet signals of the apparatus in a working regime and after shunting of one of the thermal-transformer elements.

  2. Characterizing Dissolved Gases in Cryogenic Liquid Fuels

    Science.gov (United States)

    Richardson, Ian A.

    Pressure-Density-Temperature-Composition (PrhoT-x) measurements of cryogenic fuel mixtures are a historical challenge due to the difficulties of maintaining cryogenic temperatures and precision isolation of a mixture sample. For decades NASA has used helium to pressurize liquid hydrogen propellant tanks to maintain tank pressure and reduce boil off. This process causes helium gas to dissolve into liquid hydrogen creating a cryogenic mixture with thermodynamic properties that vary from pure liquid hydrogen. This can lead to inefficiencies in fuel storage and instabilities in fluid flow. As NASA plans for longer missions to Mars and beyond, small inefficiencies such as dissolved helium in liquid propellant become significant. Traditional NASA models are unable to account for dissolved helium due to a lack of fundamental property measurements necessary for the development of a mixture Equation Of State (EOS). The first PrhoT-x measurements of helium-hydrogen mixtures using a retrofitted single-sinker densimeter, magnetic suspension microbalance, and calibrated gas chromatograph are presented in this research. These measurements were used to develop the first multi-phase EOS for helium-hydrogen mixtures which was implemented into NASA's Generalized Fluid System Simulation Program (GFSSP) to determine the significance of mixture non-idealities. It was revealed that having dissolved helium in the propellant does not have a significant effect on the tank pressurization rate but does affect the rate at which the propellant temperature rises. PrhoT-x measurements are conducted on methane-ethane mixtures with dissolved nitrogen gas to simulate the conditions of the hydrocarbon seas of Saturn's moon Titan. Titan is the only known celestial body in the solar system besides Earth with stable liquid seas accessible on the surface. The PrhoT-x measurements are used to develop solubility models to aid in the design of the Titan Submarine. NASA is currently designing the submarine

  3. Release of dissolved 85Kr by standing

    International Nuclear Information System (INIS)

    Ootsuka, Norikatsu; Yamamoto, Tadatoshi; Tsukui, Kohei

    1986-01-01

    The experiments on the release of dissolved 85 Kr by standing at room temperature were carried out to examine the influence of liquid level in a sampler and properties of solvent on the release efficiency. Six kinds of organic solvents as well as water were taken as solvents. The half-life period in case of the decrease in concentration of the dissolved 85 Kr which was used as an index of release efficiency, was proportional to the liquid level in the sampler and was inversely proportional to the diffusion coefficient of Kr gas in solvent. For organic solvents belonging to homologous series, the half-life period became longer with increasing the carbon number of solvent molecule. From the relationship between the half-life period and the carbon number, the release efficiency in the dissolved 85 Kr can be predicted for any commonly used solvent as a practical application. This method was found to be an effective means of removing the dissolved 85 Kr of low level though it takes rather long time. (author)

  4. Subcooled boiling effect on dissolved gases behaviour

    International Nuclear Information System (INIS)

    Zmitko, M.; Sinkule, J.; Linek, V.

    1999-01-01

    A model describing dissolved gasses (hydrogen, nitrogen) and ammonia behaviour in subcooled boiling conditions of WWERs was developed. Main objective of the study was to analyse conditions and mechanisms leading to formation of a zone with different concentration of dissolved gases, eg. a zone depleted in dissolved hydrogen in relation to the bulk of coolant. Both, an equilibrium and dynamic approaches were used to describe a depletion of the liquid surrounding a steam bubble in the gas components. The obtained results show that locally different water chemistry conditions can be met in the subcooled boiling conditions, especially, in the developed subcooled boiling regime. For example, a 70% hydrogen depletion in relation to the bulk of coolant takes about 1 ms and concerns a liquid layer of 1 μn surrounding the steam bubble. The locally different concentration of dissolved gases can influence physic-chemical and radiolytic processes in the reactor system, eg. Zr cladding corrosion, radioactivity transport and determination of the critical hydrogen concentration. (author)

  5. Monitoring of Thermal and Gas Activities in Mining Dump Hedvika, Czech Republic

    Science.gov (United States)

    Surovka, D.; Pertile, E.; Dombek, V.; Vastyl, M.; Leher, V.

    2017-10-01

    The negative consequences of mining of the black coal is occurrence of extractive waste storage locations - mining dumps. The mining activities carried out within the area of Ostrava are responsible for at least six mine dumps of loose materials arising as wastes from mining of mineral resources, many of which show presence of thermal processes. The thermal activity in dumps is responsible for many hazardous substances that pollute the environment and harm human health in the surroundings. This paper deals with the results of the first phase of project CZ.11.4.120/0.0/0.0/15_006/0000074 TERDUMP, on exploration of thermally active mining dumps are published in the article. As a first studied thermally active dump was a Hedvika dump. To localize of hot spots with hot gas emission was used a thermovision scanning by drone. The place with high temperature (49.8 °C) identified natural gas emission through natural cracks. Analysing the occurring pollutants in Hedvika Dump using the GC-MS or HPLC, respectively and the inert gases (CO2, CO and SO2) were determined by ion chromatography. The pollutants were determined in five sampling points during two measurements executed from July to August 2017.

  6. Non-invasive gas monitoring in newborn infants using diode laser absorption spectroscopy: a case study

    Science.gov (United States)

    Lundin, Patrik; Svanberg, Emilie K.; Cocola, Lorenzo; Lewander, Märta; Andersson-Engels, Stefan; Jahr, John; Fellman, Vineta; Svanberg, Katarina; Svanberg, Sune

    2012-03-01

    Non-invasive diode laser spectroscopy was, for the first time, used to assess gas content in the intestines and the lungs of a new-born, 4 kg, baby. Two gases, water vapor and oxygen, were studied with two low-power tunable diode lasers, illuminating the surface skin tissue and detecting the diffusely emerging light a few centimeters away. The light, having penetrated into the tissue, had experienced absorption by gas located in the lungs and in the intestines. Very distinct water vapor signals were obtained from the intestines while imprint from oxygen was lacking, as expected. Detectable, but minor, signals of water vapor were also obtained from the lungs, illuminating the armpit area and detecting below the collar bone. Water vapor signals were seen but again oxygen signals were lacking, now due to the difficulties of penetration of the oxygen probing light into the lungs of this full-term baby. Ultra-sound images were obtained both from the lungs and from the stomach of the baby. Based on dimensions and our experimental findings, we conclude, that for early pre-term babies, also oxygen should be detectable in the lungs, in addition to intestine and lung detection of water vapor. The present paper focuses on the studies of the intestines while the lung studies will be covered in a forthcoming paper.

  7. A low-cost, portable optical sensing system with wireless communication compatible of real-time and remote detection of dissolved ammonia

    Science.gov (United States)

    Deng, Shijie; Doherty, William; McAuliffe, Michael AP; Salaj-Kosla, Urszula; Lewis, Liam; Huyet, Guillaume

    2016-06-01

    A low-cost and portable optical chemical sensor based ammonia sensing system that is capable of detecting dissolved ammonia up to 5 ppm is presented. In the system, an optical chemical sensor is designed and fabricated for sensing dissolved ammonia concentrations. The sensor uses eosin as the fluorescence dye which is immobilized on the glass substrate by a gas-permeable protection layer. A compact module is developed to hold the optical components, and a battery powered micro-controller system is designed to read out and process the data measured. The system operates without the requirement of laboratory instruments that makes it cost effective and highly portable. Moreover, the calculated results in the system can be transmitted to a PC wirelessly, which allows the remote and real-time monitoring of dissolved ammonia.

  8. Using method of geotechnical diagnostics for oil and gas pipelines on the base of aerospace monitoring

    International Nuclear Information System (INIS)

    Shirinzade, A.; Gasanov, Kh.; Ragimov, R.; Timofeev, A.

    2008-01-01

    In the paper o the base of aerospatial images of decoding it is studied the problems of using the method of geotechnical diagnostics (GTD) for magistral pipelines. This technique is used for discovering potentially dangerous sections. It has been shown that the processes in geotechnical system have pecular properties on the earth surface which may be identified in terms of aerospace monitoring. Studing these properties one can conclude about state of the system as whole. It is described example of using the GTD method for practical evaluation of magistral pipeline

  9. Improving the Efficiency of Administrative Decision-Making when Monitoring Reliability and Safety of Oil and Gas Equipment

    Directory of Open Access Journals (Sweden)

    Zemenkova Maria

    2016-01-01

    Full Text Available Methodology of rapid assessment of reliability index was developed based on system analysis of technological parameters. Within functioning of on-line monitoring system of reliability index of industrial facility this method allows to increase efficiency of making managerial decisions on technical and preventive maintenance. The technique is based on the analysis of technological parameters of operational modes of pipeline transport facilities registered by dispatcher controls. The created technique can be used by the operating, research, design institutes and oil and gas transport enterprises when declaring industrial safety. The received mathematical models allow federal services of supervision, the independent expert organizations to predict the development of reliability in the registered block of dispatching data either in real time mode, or taking into account the dynamics of service conditions of the object.

  10. A Three-Step Resolution-Reconfigurable Hazardous Multi-Gas Sensor Interface for Wireless Air-Quality Monitoring Applications.

    Science.gov (United States)

    Choi, Subin; Park, Kyeonghwan; Lee, Seungwook; Lim, Yeongjin; Oh, Byungjoo; Chae, Hee Young; Park, Chan Sam; Shin, Heugjoo; Kim, Jae Joon

    2018-03-02

    This paper presents a resolution-reconfigurable wide-range resistive sensor readout interface for wireless multi-gas monitoring applications that displays results on a smartphone. Three types of sensing resolutions were selected to minimize processing power consumption, and a dual-mode front-end structure was proposed to support the detection of a variety of hazardous gases with wide range of characteristic resistance. The readout integrated circuit (ROIC) was fabricated in a 0.18 μm CMOS process to provide three reconfigurable data conversions that correspond to a low-power resistance-to-digital converter (RDC), a 12-bit successive approximation register (SAR) analog-to-digital converter (ADC), and a 16-bit delta-sigma modulator. For functional feasibility, a wireless sensor system prototype that included in-house microelectromechanical (MEMS) sensing devices and commercial device products was manufactured and experimentally verified to detect a variety of hazardous gases.

  11. Degradation and Reinforcement of Industrial Gas Tank Support Structures. Thirty-Year Long Monitoring

    Science.gov (United States)

    Krentowski, Janusz R.; Knyziak, Piotr

    2017-10-01

    An analysis of reinforced concrete supporting structures of more than a dozen liquid gas tanks mounted on tower support structures located at different sites on Poland’s territory is presented. Stability testing of the degraded structures was carried out over a period of 30 years and pointed out significant defects that prevented safe operation of the tanks containing hazardous medium. Analysing complex stress states, as well as displacements of shell structure components, the authors developed a concept of strengthening the structures. Initial repair works, which had been carried out without proper supervision, failed to meet the mandatory requirements and were not compatible with the original design solutions. After several years of operation of the reinforced structures, their degradation states were assessed again. The next stage of repair works was carried out under the supervision of the authors together with authorized representatives of the investors.

  12. Monitoring the response of the upper troposphere/lower stratosphere to a greenhouse gas scenario

    International Nuclear Information System (INIS)

    Davis, J.M.; Cox, S.K.

    1992-01-01

    During the past two years a system has been under development to contribute to this monitoring process by making measurement of the downwelling infrared radiance field at moderate spectral resolution. Sensitivity of the measurements to the presence of cirrus cloudiness, and effective particle size in cirrus clouds has been demonstrated. Sensitivity of the measurements to concentration of C0 2 and to the gross temperature structure of a 2CO 2 atmosphere have been modeled, and measurements have been made at various locations to provide a data base for further system evaluation. A temperature retrieval algorithm has been acquired and examined concerning its potential for monitoring temperature and gaseous concentration profiles. A continue research program is described herein that may be divided into three parts. First, continued system development must be pursued. This includes continued attention to the absolute accuracy of the measurements, and implementation of the Path Characterization Algorithm (retrieval code). Second, the value of long term deployment of the system at a site of considerable elevation is necessary. Third, inclusion of a solar transmission capability at moderate resolution is proposed

  13. Monitoring of use of natural gas as a preparatory stage for energy management in glass treatment

    International Nuclear Information System (INIS)

    Schoenholtz, W.; Schmidt, T.

    2004-01-01

    Registration of energy data is increasingly becoming standard practice in industries with energy-intensive production processes. Energy Management has proven its capabilities as an instrument for reduction of energy consumption and the concomitant CO 2 emissions in industry and offers many diverse potentials for quality assurance and reduction of production costs. Knowledge of the energy consumption of individual departments, processes and plant installations allows a company better process monitoring and cost calculation, combined additionally with actual-consumer-orientated energy-cost accounting. Companies should nowadays be interested not only in energy prices, as the discussion of the liberalization of the energy market may suggest, but should, instead, pursue their central interest in cutting costs and reducing overall costs for the provision of energy within the enterprise. Optimization of company energy costs thus also depends on operational questions such as that of two or three-shift operation, for example, what plant installations are used in production and how, and what load peaks occur in energy use as a result. The basic precondition for energy management is the most comprehensive possible monitoring of the quantities of energy used. The special significance of so-called 'minor consumers' in this context is examined below using an example drawn from practice. (orig.)

  14. Monitoring and groundwater/gas sampling in sands densified with explosives

    Directory of Open Access Journals (Sweden)

    Carlos A. Vega-Posada

    2014-01-01

    Full Text Available Este manuscrito presenta los resultados de un estudio de densificación de suelos en campo utilizando explosivos y realizado en un relleno sanitario localizado en Carolina de Sur, Estados Unidos; este estudio se realizó con el objeto de determinar los tipos de gases que se liberan y sus respectivas concentraciones in situ después del proceso de densificación. Se utilizó un sistema de sonda BAT para recolectar las muestras de aguas subterráneas y de gas en la mitad del estrato en estudio, así como para medir la evolución de las presiones del agua durante y después de la detonación de las cargas explosivas. Adicionalmente, se hicieron mediciones topográficas a través del eje central longitudinal de la zona de estudio después de cada explosión para medir la magnitud y la efectividad de esta técnica de densificación en depósitos de arena sueltas. Los resultados de este estudio mostraron que: a el sistema de sonda BAT puede ser una técnica confiable para recolectar muestra de agua subterránea y gas en campo antes y después de la explosión; b la masa de suelo afectada por la detonación de los explosivos licuó por un periodo de 6 horas, mientras el esfuerzo vertical efectivo alcanzó sus valores iniciales después de 3 días; y c se observaron deformaciones verticales significativas en el área de estudio después de cada explosión, lo cual indica que la masa de suelo fue exitosamente densificada.

  15. Lander based hydroacoustic monitoring of marine single bubble releases in Eckernförde Bay utilizing the multibeam based GasQuant II system.

    Science.gov (United States)

    Urban, Peter; Schneider von Deimling, Jens; Greinert, Jens

    2015-04-01

    The GEOMAR Helmholtz Centre for Ocean Research Kiel is currently developing a Imagenex Delta T based lander system for monitoring and quantifying marine gas release (bubbles). The GasQuant II is built as the successor of the GasQuant I system (Greinert, 2008), that has been successfully used for monitoring tempo-spatial variability of gas release in the past (Schneider von Deimling et al., 2010). The new system is lightweight (40 kg), energy efficient, flexible to use and built for ROV deployment with autonomous operation of up to three days. A prototype has been successfully deployed in Eckernförde Bay during the R/V ALKOR cruise AL447 in October/November 2014 to monitor the tempo-spatial variability of gas bubble seepage and to detect a possible correlation with tidal variations. Two deployments, one in forward- and one in upward looking mode, reveal extensive but scattered single bubble releases rather than distinct and more continuous sources. While these releases are difficult to detect in forward looking mode, they can unambiguously be detected in the upward looking mode even for minor gas releases, bubble rising speeds can be determined. Greinert, J., 2008. Monitoring temporal variability of bubble release at seeps: The hydroacoustic swath system GasQuant. J. Geophys. Res. Oceans Vol. 113 Issue C7 CiteID C07048 113, 7048. doi:10.1029/2007JC004704 Schneider von Deimling, J., Greinert, J., Chapman, N.R., Rabbel, W., Linke, P., 2010. Acoustic imaging of natural gas seepage in the North Sea: Sensing bubbles controlled by variable currents. Limnol. Oceanogr. Methods 8, 155. doi:10.4319/lom.2010.8.155

  16. A Real-Time Construction Safety Monitoring System for Hazardous Gas Integrating Wireless Sensor Network and Building Information Modeling Technologies.

    Science.gov (United States)

    Cheung, Weng-Fong; Lin, Tzu-Hsuan; Lin, Yu-Cheng

    2018-02-02

    In recent years, many studies have focused on the application of advanced technology as a way to improve management of construction safety management. A Wireless Sensor Network (WSN), one of the key technologies in Internet of Things (IoT) development, enables objects and devices to sense and communicate environmental conditions; Building Information Modeling (BIM), a revolutionary technology in construction, integrates database and geometry into a digital model which provides a visualized way in all construction lifecycle management. This paper integrates BIM and WSN into a unique system which enables the construction site to visually monitor the safety status via a spatial, colored interface and remove any hazardous gas automatically. Many wireless sensor nodes were placed on an underground construction site and to collect hazardous gas level and environmental condition (temperature and humidity) data, and in any region where an abnormal status is detected, the BIM model will alert the region and an alarm and ventilator on site will start automatically for warning and removing the hazard. The proposed system can greatly enhance the efficiency in construction safety management and provide an important reference information in rescue tasks. Finally, a case study demonstrates the applicability of the proposed system and the practical benefits, limitations, conclusions, and suggestions are summarized for further applications.

  17. CBERS-2B Brazilian remote sensing satellite to help to monitor the Bolivia-Brazil gas pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Hernandes, Gilberto Luis Sanches [TBG Transportadora Brasileira Gasoduto Bolivia-Brasil, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This paper presents the results of CBERS-2B' Brazilian Remote Sensing Satellite to help to monitor the Bolivia-Brazil Gas Pipeline. The CBERS-2B is the third satellite launched in 2007 by the CBERS Program (China-Brazil Earth Resources Satellite) and the innovation was the HRC camera that produces high resolution images. It will be possible to obtain one complete coverage of the country every 130 days. In this study, 2 images from different parts of the Bolivia- Brazil Gas Pipeline were selected. Image processing involved the geometric registration of CBERS-2B satellite images with airborne images, contrast stretch transform and pseudo color. The analysis of satellite and airborne images in a GIS software to detect third party encroachment was effective to detect native vegetation removal, street construction, growth of urban areas, farming and residential/industrial land development. Very young, the CBERS-2B is a good promise to help to inspect the areas along the pipelines. (author)

  18. Preliminary Monitoring of Soil gas Radon in Potentially Active Faults, San Sai District, Chiang Mai Province, Thailand

    Science.gov (United States)

    Pondthai, P.; Udphuay, S.

    2013-05-01

    The magnitude of 5.1 Mw earthquake occurred in San Sai District, Chiang Mai Province, Thailand in December 2006 was considered an uncommon event due to the fact that there was no statistical record of such significant earthquake in the area. Therefore the earthquake might have been associated with a potentially active fault zone within the area. The objective of this study is to measure soil gas radon across this unknown fault zone within the Chiang Mai Basin, northern Thailand. Two profiles traversing the expected fault zone of soil gas radon measurements have been monitored, using TASTRAK solid state track nuclear detectors (SSNTDs). Radon signals from three periods of measurement show a distinctive consistent spatial distribution pattern. Anomalous radon areas along the profiles are connected to fault locations previously interpreted from other geophysical survey results. The increased radon signal changes from the radon background level with the signal-to-background ratio above 3 are considered anomalous. Such pattern of radon anomaly supports the existence of the faults. The radon measurement, therefore is a powerful technique in mapping active fault zone.

  19. Origin and in situ concentrations of hydrocarbons in the Kumano forearc basin from drilling mud gas monitoring during IODP NanTroSEIZE Exp. 319

    International Nuclear Information System (INIS)

    Wiersberg, Thomas; Schleicher, Anja M.; Horiguchi, Keika; Doan, Mai-Linh; Eguchi, Nobuhisa; Erzinger, Jörg

    2015-01-01

    Highlights: • Exp. 319 of IODP was the first cruise in the history of scientific ocean drilling with drilling mud gas monitoring. • Hydrocarbons were the only formation-derived gases identified in drilling mud. • Chemical and isotopic compositions of hydrocarbons exhibit a microbial origin. • Absolute CH 4 concentrations in the formation reaching up to 24 L gas /L sediment . - Abstract: NanTroSEIZE Exp. 319 of the Integrated Ocean Drilling Program (IODP) was the first cruise in the history of scientific ocean drilling with drilling mud circulation through a riser. Drilling mud was pumped through the drill string and returned to the drill ship through the riser pipe during drilling of hole C0009A from 703 to 1604 mbsf (meter below sea floor) and hole enlargement from 703 to 1569 mbsf. During riser drilling, gas from returning drilling mud was continuously extracted, sampled and analyzed in real time to reveal information on the gas composition and gas concentrations at depth. Hydrocarbons were the only formation-derived gases identified in drilling mud and reached up to 14 vol.% of methane and 48 ppmv of ethane. The chemical and isotopic compositions of hydrocarbons exhibit a microbial origin. Hydrocarbons released from drilling mud and cuttings correlate with visible allochthonous material (wood, lignite) in drilling cuttings. At greater depth, addition of small but increasing amounts of hydrocarbons probably from low-temperature thermal degradation of organic matter is indicated. The methane content is also tightly correlated with several intervals of low Poisson’s ratio from Vp/Vs observed in sonic velocity logs, suggesting that the gas is situated in the pore space of the rock as free gas. The gas concentrations in the formation, determined from drilling mud gas monitoring, reaching up to 24 L gas /L sediment for methane in hole C0009A, in line with gas concentrations from interpreted downhole sonic logs

  20. Asset monitoring in the upstream oil and gas industry : wireless, the fusion of industrial automation and business performance

    Energy Technology Data Exchange (ETDEWEB)

    Shuster, D. [IBM Wireless, IBM Global Services, Markham, ON (Canada)

    2004-07-01

    This keynote presentation addressed issues concerning the accurate management of assets and meeting business objectives with specific reference to new communications technologies in the oil and gas industry. An outline of various communications challenges specific to the oil and gas industry were reviewed, including: field technicians; inspections; predictive, preventive and corrective maintenance tasks; and the need for greater efficiency across large geographic areas. The concept of reporting critical data back to a central data repository to improve performance, cost management and regulatory programs was introduced. The benefits of remote monitoring and control in the petroleum industry were outlined. An overview of effective business approaches including initiatives and operating costs was presented. High impact transformation priorities in the oil and gas sector were also reviewed. A new business model was presented in which a differentiation was distinguished between process re-engineering and the more recent tenets of on-demand business. The deepening relationship of information technology with business was outlined in a business model, suggesting a trend towards modular business components that were easily defined and manipulated. Other significant benefits and ideas included: a demonstration of business opportunities through the creation of a real-time enterprise linked by separate systems; the use of information technology to extend business systems; and integrated, standards based business systems. A list of new options was presented, including sensor technology, new communications options and greater flexibility and reliability through the use of Information Technology architectures. A list of value propositions of upstream petroleum was given, including a chart with percentages of projected savings and efficiency increases. In addition, business advantages through new SCADA technologies and applications were presented, including scalability and new

  1. Development of Information Support of the Automated System for Monitoring the State of the Gas Transportation System’s Industrial Safety

    Directory of Open Access Journals (Sweden)

    Ruslan Skrynkovskyy

    2017-08-01

    Full Text Available The purpose of the article is to developing the information security of the automated system for monitoring the state of industrial safety of the gas transportation system within the framework of the safety management system, which will enable timely and objective detection of adverse accident hazards (hazardous events and taking the necessary specific measures to eliminate them and operate the gas transport system safely. It is proved that the basis of the information provision of the automated system for monitoring the state of the industrial safety of the gas transmission system is a methodology that includes the following basic procedures: identifying hazards; qualitative and quantitative assessment of emergencies; establishing of unacceptable (unallowable risks and their introduction to the information base (register of unacceptable risks of objects of the gas transportation system; comprehensive assessment and certification of the state of industrial safety of objects of the gas transportation system; identification of effective, productive (efficient risk management measures. The prospect of further research in this area is the development and implementation of an automated system for monitoring the state of industrial safety of the objects of the gas transmission system based on the results of the research (of the submitted information provision.

  2. Elimination of effect of α-particles in tritium gas monitor

    International Nuclear Information System (INIS)

    Matsumoto, Yuzuru; Asaoka, Koichi; Manako, Hiroaki; Kumabe, Isao

    1982-01-01

    In order to obtain the high sensitivity in a tritium monitor, a cancellation circuit for α-particles emitted by Rn in air was designed and constructed. The cancellation circuit consists of a differentiating circuit, discriminator, peak-hold circuit and difference amplifier. Pulsed signals induced by α-particles are separated from tritium #betta#-signals by the differentiating circuit and the discriminator. After being shaped by the peak-hold circuit with the same decay time constant as that of the initial α-signals, the α-signals are subtracted from the initial signals by the difference amplifier. The experimental test of this system was carried out, and it was confirmed that the elimination of the effect of α-particles was achieved successfully by the use of this cancellation circuit. (author)

  3. Current Status of the Advanced Residual Gas Monitor for Heavy Ion Synchrotron Applications

    CERN Document Server

    Liakin, D A; Sergeeva, O; Skachkov, V S

    2005-01-01

    The challenge and complexity of the advanced RGM requires very careful design of each structural component of the monitor and special attention to match the properties of different subsystems. In the present paper the status of the high performance readout electronics is discussed. Single optical decoupled profile measurement channel (one of 100) with 14 bit resolution and 10 MHz bandwidth was tested and step-by-step improved. Special attention had been paid to the noise cancellation and digital data processing algorithms optimization. Another important point is a proper electromagnetic guiding system design. As it is shown, high field homogeneity, which is required for sub-millimeter spatial resolution, can be achieved despite the presence of the field-distorting hole for the light signal transmitting. The low energy (down to 10MeV per nucleon) beam disturbance compensation methods are also discussed. The ionization process and electron dynamics simulations are used for proving this system design.

  4. Environmental monitoring survey of oil and gas fields in Region II in 2009. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    2010-03-15

    The oil companies Statoil ASA, ExxonMobil Exploration and Production Norway AS, Total E&P Norge AS, Talisman Energy Norge AS and Marathon Petroleum Norge AS commissioned Section of Applied Environmental Research at UNI RESEARCH AS to undertake the monitoring survey of Region II in 2009. Similar monitoring surveys in Region II have been carried out in 1996, 2000, 2003 and 2006. The survey in 2009 included in total 18 fields: Rev, Varg, Sigyn, Sleipner Vest, Sleipner OEst, Sleipner Alfa Nord, Glitne, Grane, Balder, Ringhorne, Jotun, Vale, Skirne, Byggve, Heimdal, Volve, Vilje og Alvheim. Sampling was conducted from the vessel MV Libas between May 18 and May 27. Samples were collected from in totally 137 sampling sites, of which 15 were regional sampling sites. Samples for chemical analysis were collected at all sites, whereas samples for benthos analysis were collected at 12 fields. As in previous surveys, Region II is divided into natural sub-regions. One sub-region is shallow (77-96 m) sub-region, a central sub-region (107-130 m) and a northern subregion (115-119 m). The sediments of the shallow sub-region had relatively lower content of TOM and pelite and higher content of fine sand than the central and northern sub-regions. Calculated areas of contamination are shown for the sub-regions in Table 1.1. The fields Sigyn, Sleipner Alfa Nord, Glitne, Grane, Balder, Ringhorne, Jotun, Skirne, Byggve, Vilje og Alvheim showed no contamination of THC. At the other fields there were minor changes from 2006. The concentrations of barium increased in the central sub-region from 2006 to 2009, also at fields where no drilling had been undertaken during the last years. The same laboratory and methods are used during the three last regional investigations. The changes in barium concentrations may be due to high variability of barium concentrations in the sediments. This is supported by relatively large variations in average barium concentrations at the regional sampling sites in

  5. Evaluation of microwave cavity gas sensor for in-vessel monitoring of dry cask storage systems

    Science.gov (United States)

    Bakhtiari, S.; Gonnot, T.; Elmer, T.; Chien, H.-T.; Engel, D.; Koehl, E.; Heifetz, A.

    2018-04-01

    Results are reported of research activities conducted at Argonne to assess the viability of microwave resonant cavities for extended in-vessel monitoring of dry cask storage system (DCSS) environment. One of the gases of concern to long-term storage in canisters is water vapor, which appears due to evaporation of residual moisture from incompletely dried fuel assembly. Excess moisture could contribute to corrosion and deterioration of components inside the canister, which would in turn compromise maintenance and safe transportation of such systems. Selection of the sensor type in this work was based on a number of factors, including good sensitivity, fast response time, small form factor and ruggedness of the probing element. A critical design constraint was the capability to mount and operate the sensor using the existing canister penetrations-use of existing ports for thermocouple lances. Microwave resonant cavities operating at select resonant frequency matched to the rotational absorption line of the molecule of interest offer the possibility of highly sensitive detection. In this study, two prototype K-band microwave cylindrical cavities operating at TE01n resonant modes around the 22 GHz water absorption line were developed and tested. The sensors employ a single port for excitation and detection and a novel dual-loop inductive coupling for optimized excitation of the resonant modes. Measurement of the loaded and unloaded cavity quality factor was obtained from the S11 parameter. The acquisition and real-time analysis of data was implemented using software based tools developed for this purpose. The results indicate that the microwave humidity sensors developed in this work could be adapted to in-vessel monitoring applications that require few parts-per-million level of sensitivity. The microwave sensing method for detection of water vapor can potentially be extended to detection of radioactive fission gases leaking into the interior of the canister through

  6. A novel headspace gas chromatographic method for in situ monitoring of monomer conversion during polymerization in an emulsion environment.

    Science.gov (United States)

    Chai, Xin-Sheng; Zhong, Jin-Feng; Hu, Hui-Chao

    2012-05-18

    This paper describes a novel multiple-headspace extraction/gas chromatographic (MHE-GC) technique for monitoring monomer conversion during a polymerization reaction in a water-based emulsion environment. The polymerization reaction of methyl methacrylate (MMA) in an aqueous emulsion is used as an example. The reaction was performed in a closed headspace sample vial (as a mini-reactor), with pentane as a tracer. In situ monitoring of the vapor concentration of the tracer, employing a multiple headspace extraction (sampling) scheme, coupled to a GC, makes it possible to quantitatively follow the conversion of MMA during the early stages of polymerization. Data on the integrated amount of the tracer vapor released from the monomer droplet phase during the polymerization is described by a mathematic equation from which the monomer conversion can be calculated. The present method is simple, automated and economical, and provides an efficient tool in the investigation of the reaction kinetics and effects of the reaction conditions on the early stage of polymerization. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Carbon isotopic analysis of atmospheric methane by isotope-ratio-monitoring gas chromatography-mass spectrometry

    Science.gov (United States)

    Merritt, Dawn A.; Hayes, J. M.; Des Marais, David J.

    1995-01-01

    Less than 15 min are required for the determination of delta C(sub PDB)-13 with a precision of 0.2 ppt(1 sigma, single measurement) in 5-mL samples of air containing CH4 at natural levels (1.7 ppm). An analytical system including a sample-introduction unit incorporating a preparative gas chromatograph (GC) column for separation of CH4 from N2, O2, and Ar is described. The 15-min procedure includes time for operation of that system, high-resolution chromatographic separation of the CH4, on-line combustion and purification of the products, and isotopic calibration. Analyses of standards demonstrate that systematic errors are absent and that there is no dependence of observed values of delta on sample size. For samples containing 100 ppm or more CH4, preconcentration is not required and the analysis time is less than 5 min. The system utilizes a commercially available, high-sensitivity isotope-ratio mass spectrometer. For optimal conditions of smaple handling and combustion, performance of the system is within a factor of 2 of the shot-noise limit. The potential exists therefore for analysis of samples as small as 15 pmol CH4 with a standard deviation of less than 1 ppt.

  8. Seismically induced variations in Mariánské Lázně fault gas composition in the NW Bohemian swarm quake region, Czech Republic — A continuous gas monitoring

    Czech Academy of Sciences Publication Activity Database

    Weinlich, F. H.; Faber, E.; Boušková, Alena; Horálek, Josef; Teschner, M.; Poggenburg, J.

    2006-01-01

    Roč. 421, č. 1-2 (2006), s. 89-110 ISSN 0040-1951 Institutional research plan: CEZ:AV0Z30120515 Keywords : gas monitoring * earthquake swarm * coseismic anomalies Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.675, year: 2006

  9. Perspective: Chemical reactions in ionic liquids monitored through the gas (vacuum)/liquid interface.

    Science.gov (United States)

    Maier, F; Niedermaier, I; Steinrück, H-P

    2017-05-07

    This perspective analyzes the potential of X-ray photoelectron spectroscopy under ultrahigh vacuum (UHV) conditions to follow chemical reactions in ionic liquids in situ. Traditionally, only reactions occurring on solid surfaces were investigated by X-ray photoelectron spectroscopy (XPS) in situ. This was due to the high vapor pressures of common liquids or solvents, which are not compatible with the required UHV conditions. It was only recently realized that the situation is very different when studying reactions in Ionic Liquids (ILs), which have an inherently low vapor pressure, and first studies have been performed within the last years. Compared to classical spectroscopy techniques used to monitor chemical reactions, the advantage of XPS is that through the analysis of their core levels all relevant elements can be quantified and their chemical state can be analyzed under well-defined (ultraclean) conditions. In this perspective, we cover six very different reactions which occur in the IL, with the IL, or at an IL/support interface, demonstrating the outstanding potential of in situ XPS to gain insights into liquid phase reactions in the near-surface region.