Academic literature on the topic 'CO2 and CH4 Leak detection'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'CO2 and CH4 Leak detection.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "CO2 and CH4 Leak detection"
1
Dherbecourt, Jean-Baptiste, Jean-Michel Melkonian, Antoine Godard, Vincent Lebat, Nicolas Tanguy, Cedric Blanchard, Stéphanie Doz, et al. "NAOMI GAZL: A Multispecies DIAL Tested on the TADI Gas Leak Simulation Facility." EPJ Web of Conferences 237 (2020): 03016. http://dx.doi.org/10.1051/epjconf/202023703016.
Full textAbstract:
We report on a direct detection differential absorption lidar (DIAL), designed for remote detection of CH4 and CO2. The system is based on a single-frequency optical parametric oscillator/amplifier system, tunable in the 1.57-1.65 µm range. The DIAL system, called NAOMI GAZL, was tested on a controlled gas release facility in October 2018.
2
Kuze, Akihiko, Nobuhiro Kikuchi, Fumie Kataoka, Hiroshi Suto, Kei Shiomi, and Yutaka Kondo. "Detection of Methane Emission from a Local Source Using GOSAT Target Observations." Remote Sensing 12, no. 2 (January 13, 2020): 267. http://dx.doi.org/10.3390/rs12020267.
Full textAbstract:
Emissions of atmospheric methane (CH4), which greatly contributes to radiative forcing, have larger uncertainties than those for carbon dioxide (CO2). The Thermal And Near-infrared Sensor for carbon Observation Fourier-Transform Spectrometer (TANSO-FTS) onboard the Greenhouse gases Observing SATellite (GOSAT) launched in 2009 has demonstrated global grid observations of the total column density of CO2 and CH4 from space, and thus reduced uncertainty in the global flux estimation. In this paper, we present a case study on local CH4 emission detection from a single-point source using an available series of GOSAT data. By modifying the grid observation pattern, the pointing mechanism of TANSO-FTS targets a natural gas leak point at Aliso Canyon in Southern California, where the clear-sky frequency is high. To enhance local emission estimates, we retrieved CO2 and CH4 partial column-averaged dry-air mole fractions of the lower troposphere (XCO2 (LT) and XCH4 (LT)) by simultaneous use of both sunlight reflected from Earth’s surface and thermal emissions from the atmosphere. The time-series data of Aliso Canyon showed a large enhancement that decreased with time after its initial blowout, compared with reference point data and filtered with wind direction simulated by the Weather Research and Forecasting (WRF) model.
3
Russ, Tamara, Joseph R. Stetter, Eric Luong, Avadhkumar Jitubhai Patel, and Winncy Du. "(Invited) Detection, Location and Quantification of H2 Gas Leaks Based on Data Collected with Electrochemical Sensors in a Specifically Designed Test Chamber." ECS Meeting Abstracts MA2024-01, no. 51 (August 9, 2024): 2756. http://dx.doi.org/10.1149/ma2024-01512756mtgabs.
Full textAbstract:
Hydrogen is one of the most important energy gases as it is carbon free and therefore can result in the emission reduction of the greenhouse gas CO2. However, hydrogen itself is a secondary greenhouse gas. As a secondary greenhouse gas, hydrogen does not directly add to global warming by entrapping heat. Instead, it reacts with molecules in the atmosphere that are needed to remove the greenhouse gas CH4. CH4 is comparably short-lived in the atmosphere with approximately 10 years compared to CO2 which can last in the atmosphere for centuries. However, CH4 traps at least 100 times as much heat as CO2. Considering the difference in heat capacities of CH4 and CO2, combined with the difference in lifetime, if the same amount of CH4 and CO2 were to be released into the atmosphere at the same time, the global warming effect of CH4 would be approximately 28 times higher than the warming effect of CO2. This means, by releasing hydrogen in the atmosphere, the global warming effect is indirectly enhanced by increasing the lifetime of CH4. Therefore, it is essential to be able to detect, locate and quantify hydrogen leaks right away. Due to the ever-growing hydrogen infrastructure including production facilities, transportation systems like pipelines, as well as storage facilities and user end stations, it is essential to create low-cost, low-power sensors that can be deployed in high numbers. Electrochemical sensors have the potential to fulfill all the needed criteria and are already used for the detection of hydrogen. However, in order to use these sensors to not only detect the leak, but also to locate and quantify the amount of hydrogen that leaked into the atmosphere, additional models and algorithms are needed. To our knowledge, no system currently exists on the market that can be used to fulfill all three tasks. We built a test chamber that enabled us to evaluate H2 leaks and to collect data with electrochemical sensors in a controlled room and environment. The chamber has the size of 800 x 400 x 450 mm3 with a total volume of 144 L. We placed seven of our commercial electrochemical sensors that can detect 0 – 250 ppm hydrogen at different positions inside the box. The box was equipped with one gas inlet and one gas outlet to ensure pressure stability inside the box during our leak test. The inlet was connected to a gas tube which was connected to two mass flow controllers as well as to an outlet tube via a three-way valve. This way, it could be ensured that the gas stream had a stable volume and a constant speed. We released controlled amounts of hydrogen into the box and collected the data with our seven sensors. We were able to see a location-dependent sensor response over time for a 1 second leak of H2 which indicates the capability of such a sensor system to be used for the location of a leak. Quantifying hydrogen is a very complex issue. It requires extremely accurate readings and an intelligent algorithm that is capable to use the reading from multiple sensors and turn that into a mass of hydrogen leaked or leaking. The extremely accurate reading is difficult because the zero and span readouts from the electrochemical sensor is dependent on temperature as well as humidity. This means that the readout zero and span will have to be compensated for both temperature and humidity. While we currently use algorithms to compensate for temperature, we found that these algorithms are not good enough when the sensors are used to measure concentrations in the low-ppm or ppb range. We are researching AI and other computational means to include both temperature and humidity in the compensation algorithms and how including both variables in the compensation process can improve the sensors performance at low concentrations. Both the H2 sensor and its deployment capabilities are technologically and economically significant to the rapidly expanding H2 market for protecting human health, the environment, stemming expensive product losses and promoting efficient use.
4
Yang, Mingxi, John Prytherch, Elena Kozlova, Margaret J. Yelland, Deepulal Parenkat Mony, and Thomas G. Bell. "Comparison of two closed-path cavity-based spectrometers for measuring air–water CO<sub>2</sub> and CH<sub>4</sub> fluxes by eddy covariance." Atmospheric Measurement Techniques 9, no. 11 (November 18, 2016): 5509–22. http://dx.doi.org/10.5194/amt-9-5509-2016.
Full textAbstract:
Abstract. In recent years several commercialised closed-path cavity-based spectroscopic instruments designed for eddy covariance flux measurements of carbon dioxide (CO2), methane (CH4), and water vapour (H2O) have become available. Here we compare the performance of two leading models – the Picarro G2311-f and the Los Gatos Research (LGR) Fast Greenhouse Gas Analyzer (FGGA) at a coastal site. Both instruments can compute dry mixing ratios of CO2 and CH4 based on concurrently measured H2O, temperature, and pressure. Additionally, we used a high throughput Nafion dryer to physically remove H2O from the Picarro airstream. Observed air–sea CO2 and CH4 fluxes from these two analysers, averaging about 12 and 0.12 mmol m−2 day−1 respectively, agree within the measurement uncertainties. For the purpose of quantifying dry CO2 and CH4 fluxes downstream of a long inlet, the numerical H2O corrections appear to be reasonably effective and lead to results that are comparable to physical removal of H2O with a Nafion dryer in the mean. We estimate the high-frequency attenuation of fluxes in our closed-path set-up, which was relatively small ( ≤ 10 %) for CO2 and CH4 but very large for the more polar H2O. The Picarro showed significantly lower noise and flux detection limits than the LGR. The hourly flux detection limit for the Picarro was about 2 mmol m−2 day−1 for CO2 and 0.02 mmol m−2 day−1 for CH4. For the LGR these detection limits were about 8 and 0.05 mmol m−2 day−1. Using global maps of monthly mean air–sea CO2 flux as reference, we estimate that the Picarro and LGR can resolve hourly CO2 fluxes from roughly 40 and 4 % of the world's oceans respectively. Averaging over longer timescales would be required in regions with smaller fluxes. Hourly flux detection limits of CH4 from both instruments are generally higher than the expected emissions from the open ocean, though the signal to noise of this measurement may improve closer to the coast.
5
Halley, Sleight, Kannan Ramaiyan, James Smith, Robert Ian, Kamil Agi, Fernando H. Garzon, and Lok-kun Tsui. "Mixed Potential Electrochemical Sensors for Natural Gas Leak Detection – Field Testing of Portable Sensor Package." ECS Meeting Abstracts MA2023-01, no. 52 (August 28, 2023): 2604. http://dx.doi.org/10.1149/ma2023-01522604mtgabs.
Full textAbstract:
According to the EPA, methane (CH4) emissions from oil and gas infrastructure accounted for 211 million metric tons of CO2 equivalent in 2020 [1]. Actual emissions may exceed this by a factor of three [2]. Current natural gas leak detection technologies largely consist of optical sensors such as IR spectrometers [3]. Optical sensors have high sensitivity, but the high cost and fragility of these sensors limit practical applications and continuous monitoring in the field. Mixed potential electrochemical sensors (MPES) are low cost, robust, selective and sensitive, making them a viable option for continuous natural gas leak detection [4]. While we have previously reported on the development of these sensors for natural gas detection in the laboratory, it is necessary to evaluate how these sensors perform in relevant environments. The MPES device consists of La0.87Sr0.13CrO3 (LSC), indium tin oxide (ITO, In2O3 90 wt%, SnO2 10 wt%), and Au sensing electrodes with a Pt pseudo-reference electrode, bridged by 3 mol% YSZ solid electrolyte. A low ionic conductivity magnesia stabilized zirconia (MSZ) substrate is used to enhance sensitivity with a demonstrated limit of detection (LOD) of < 40 ppm. The sensor is integrated with an internet of things (IoT) data collection and transmission package developed by SensorComm Technologies. Field testing was performed at Colorado State University’s Methane Emission Technology Evaluation Center (METEC). The sensors’ capability of detecting buried pipeline leaks was investigated by varying the leak rate from 7.2 SLPM to 37 SLPM, lateral sensor distance from 0 meters to 3 meters, and vertical distance from 0 meters to 0.28 meters (Figure 1). Machine learning methods were applied to a training dataset collected in the laboratory to quantify the CH4 concentration. These results serve as a first demonstration that a low-cost mixed potential electrochemical sensor system can successfully detect underground pipeline emissions and quantify CH4 concentrations that are in agreement with previously published results [6] collected using more complex and costly methods. References: [1] O. US EPA, “Estimates of Methane Emissions by Segment in the United States,” Aug. 27, 2018. https://www.epa.gov/natural-gas-star-program/estimates-methane-emissions-segment-united-states (accessed Dec. 08, 2022). [2] A. J. Marchese et al., “Methane Emissions from United States Natural Gas Gathering and Processing,” Environ. Sci. Technol., vol. 49, no. 17, pp. 10718–10727, Sep. 2015, doi: 10.1021/acs.est.5b02275. [3] T. Aldhafeeri, M.-K. Tran, R. Vrolyk, M. Pope, and M. Fowler, “A Review of Methane Gas Detection Sensors: Recent Developments and Future Perspectives,” Inventions, vol. 5, no. 3, Art. no. 3, Sep. 2020, doi: 10.3390/inventions5030028. [4] F. H. Garzon, R. Mukundan, and E. L. Brosha, “Solid-state mixed potential gas sensors: theory, experiments and challenges,” Solid State Ion., vol. 136–137, pp. 633–638, Nov. 2000, doi: 10.1016/S0167-2738(00)00348-9. [5] S. Halley, L. Tsui, and F. Garzon, “Combined Mixed Potential Electrochemical Sensors and Artificial Neural Networks for the Quantificationand Identification of Methane in Natural Gas Emissions Monitoring,” J. Electrochem. Soc., vol. 168, no. 9, p. 097506, Sep. 2021, doi: 10.1149/1945-7111/ac2465. [6] B. A. Ulrich, M. Mitton, E. Lachenmeyer, A. Hecobian, D. Zimmerle, and K. M. Smits, “Natural Gas Emissions from Underground Pipelines and Implications for Leak Detection,” Environ. Sci. Technol. Lett., vol. 6, no. 7, pp. 401–406, Jul. 2019, doi: 10.1021/acs.estlett.9b00291. Figure 1: Sensor response to various heights above a simulated buried pipeline leak on two successive days of testing (a and b), and estimated CH4 concentrations from sensor data (c). Figure 1
6
Zellweger, Christoph, Lukas Emmenegger, Mohd Firdaus, Juha Hatakka, Martin Heimann, Elena Kozlova, T. Gerard Spain, Martin Steinbacher, Marcel V. van der Schoot, and Brigitte Buchmann. "Assessment of recent advances in measurement techniques for atmospheric carbon dioxide and methane observations." Atmospheric Measurement Techniques 9, no. 9 (September 26, 2016): 4737–57. http://dx.doi.org/10.5194/amt-9-4737-2016.
Full textAbstract:
Abstract. Until recently, atmospheric carbon dioxide (CO2) and methane (CH4) measurements were made almost exclusively using nondispersive infrared (NDIR) absorption and gas chromatography with flame ionisation detection (GC/FID) techniques, respectively. Recently, commercially available instruments based on spectroscopic techniques such as cavity ring-down spectroscopy (CRDS), off-axis integrated cavity output spectroscopy (OA-ICOS) and Fourier transform infrared (FTIR) spectroscopy have become more widely available and affordable. This resulted in a widespread use of these techniques at many measurement stations. This paper is focused on the comparison between a CRDS "travelling instrument" that has been used during performance audits within the Global Atmosphere Watch (GAW) programme of the World Meteorological Organization (WMO) with instruments incorporating other, more traditional techniques for measuring CO2 and CH4 (NDIR and GC/FID). We demonstrate that CRDS instruments and likely other spectroscopic techniques are suitable for WMO/GAW stations and allow a smooth continuation of historic CO2 and CH4 time series. Moreover, the analysis of the audit results indicates that the spectroscopic techniques have a number of advantages over the traditional methods which will lead to the improved accuracy of atmospheric CO2 and CH4 measurements.
7
Zaini, Zaini, and Taffany Hudalil Alvy. "Design of Monitoring System for Hazardous Gas and Fire Detection In Building Based On Internet of Things." Andalas Journal of Electrical and Electronic Engineering Technology 2, no. 1 (June 24, 2022): 13–20. http://dx.doi.org/10.25077/ajeeet.v2i1.20.
Full textAbstract:
Fires and gas leaks are events that still occur frequently. This incident is usually caused by various factors including leakage of LPG gas cylinders, cigarette butts that are disposed of carelessly, short circuits of electric current and so on. Generally, fires and gas leaks can only be detected if the fire has already grown or a lot of smoke comes out of the building. Therefore, a monitoring system for detecting dangerous gases and fires in buildings based on the Internet of Things was created that can monitor the condition of the building through a website as well as send notifications to the Telegram application on smartphones. The detection system implemented uses a flame sensor as a fire detector, an MQ-2 gas sensor as a detector of hazardous gases (CO, CO2, and CH4), and NodeMCU as a module to transmit data. The system will work continuously in real time, if gas is detected that exceeds the threshold or a fire is detected, the system will send a notification to Telegram and the website will display the value and status of the sensor and a map of the area where the fire or gas leak occurred. The results of the detection system created to be able to provide solutions so that cases of fire and gas leaks can be handled early by detecting signs of fire or gas leaks and sending the information to users via the website and notifications.
8
Dowd, Emily, Alistair J. Manning, Bryn Orth-Lashley, Marianne Girard, James France, Rebecca E. Fisher, Dave Lowry, et al. "First validation of high-resolution satellite-derived methane emissions from an active gas leak in the UK." Atmospheric Measurement Techniques 17, no. 5 (March 18, 2024): 1599–615. http://dx.doi.org/10.5194/amt-17-1599-2024.
Full textAbstract:
Abstract. Atmospheric methane (CH4) is the second-most-important anthropogenic greenhouse gas and has a 20-year global warming potential 82 times greater than carbon dioxide (CO2). Anthropogenic sources account for ∼ 60 % of global CH4 emissions, of which 20 % come from oil and gas exploration, production and distribution. High-resolution satellite-based imaging spectrometers are becoming important tools for detecting and monitoring CH4 point source emissions, aiding mitigation. However, validation of these satellite measurements, such as those from the commercial GHGSat satellite constellation, has so far not been documented for active leaks. Here we present the monitoring and quantification, by GHGSat's satellites, of the CH4 emissions from an active gas leak from a downstream natural gas distribution pipeline near Cheltenham, UK, in the spring and summer of 2023 and provide the first validation of the satellite-derived emission estimates using surface-based mobile greenhouse gas surveys. We also use a Lagrangian transport model, the UK Met Office's Numerical Atmospheric-dispersion Modelling Environment (NAME), to estimate the flux from both satellite- and ground-based observation methods and assess the leak's contribution to observed concentrations at a local tall tower site (30 km away). We find GHGSat's emission estimates to be in broad agreement with those made from the in situ measurements. During the study period (March–June 2023) GHGSat's emission estimates are 236–1357 kg CH4 h−1, whereas the mobile surface measurements are 634–846 kg CH4 h−1. The large variability is likely down to variations in flow through the pipe and engineering works across the 11-week period. Modelled flux estimates in NAME are 181–1243 kg CH4 h−1, which are lower than the satellite- and mobile-survey-derived fluxes but are within the uncertainty. After detecting the leak in March 2023, the local utility company was contacted, and the leak was fixed by mid-June 2023. Our results demonstrate that GHGSat's observations can produce flux estimates that broadly agree with surface-based mobile measurements. Validating the accuracy of the information provided by targeted, high-resolution satellite monitoring shows how it can play an important role in identifying emission sources, including unplanned fugitive releases that are inherently challenging to identify, track, and estimate their impact and duration. Rapid, widespread access to such data to inform local action to address fugitive emission sources across the oil and gas supply chain could play a significant role in reducing anthropogenic contributions to climate change.
9
Bonne, Jean-Louis, Ludovic Donnat, Grégory Albora, Jérémie Burgalat, Nicolas Chauvin, Delphine Combaz, Julien Cousin, et al. "A measurement system for CO2 and CH4 emissions quantification of industrial sites using a new in situ concentration sensor operated on board uncrewed aircraft vehicles." Atmospheric Measurement Techniques 17, no. 14 (July 26, 2024): 4471–91. http://dx.doi.org/10.5194/amt-17-4471-2024.
Full textAbstract:
Abstract. We developed and tested a complete measurement system to quantify CO2 and CH4 emissions at the scale of an industrial site based on the innovative sensor Airborne Ultra-light Spectrometer for Environmental Application (AUSEA), operated on board uncrewed aircraft vehicles (UAVs). The AUSEA sensor is a new light-weight (1.4 kg) open-path laser absorption spectrometer simultaneously recording in situ CO2 and CH4 concentrations at high frequency (24 Hz in this study) with precisions of 10 ppb for CH4 and 1 ppm for CO2 (when averaged at 1 Hz). It is suitable for industrial operation at a short distance from the sources (sensitivity up to 1000 ppm for CO2 and 200 ppm for CH4). Greenhouse gas concentrations monitored by this sensor throughout a plume cross section downwind of a source drive a simple mass balance model to quantify emissions from this source. This study presents applications of this method to different pragmatic cases representative of real-world conditions for oil and gas facilities. Two offshore oil and gas platforms were monitored for which our emissions estimates were coherent with mass balance and combustion calculations from the platforms. Our method has also been compared to various measurement systems (gas lidar, multispectral camera, infrared camera including concentrations and emissions quantification system, acoustic sensors, ground mobile and fixed cavity ring-down spectrometers) during controlled-release experiments conducted on the TotalEnergies Anomaly Detection Initiatives (TADI) test platform at Lacq, France. It proved suitable to detect leaks with emission fluxes down to 0.01 g s−1, with 24 % of estimated CH4 fluxes within the −20 % to +20 % error range, 80 % of quantifications within the −50 % to +100 % error range and all of our results within the −69 % to +150 % error range. Such precision levels are better ranked than current top-down alternative techniques to quantify CH4 at comparable spatial scales. This method has the potential to be operationally deployed on numerous sites and on a regular basis to evaluate the space- and time-dependent greenhouse gas emissions of oil and gas facilities.
10
Hermon, Dedi. "Impacts of land cover change on climate trend in Padang Indonesia." Indonesian Journal of Geography 46, no. 2 (December 31, 2014): 138. http://dx.doi.org/10.22146/ijg.5783.
Full textAbstract:
ἀe purpose of this study was to analyze the trend of climate change through changes in the elements of Green House Gases (GHGs), includes the trend of CO2, N2O, and CH4. ἀe change of the extreme rainfall and temperature indices due to land cover change into developed area in Padang. IdentiḀcation and analysis trends of climate change and extreme climatic events were analyzed by using RclimDex the Expert Team for Climate Change Detection and Indices (ETCCDMI) technique. Where as the analysis and interpretation of land cover changes into developed area used Landsat TM 5 and Landsat 1985 7 ETM + of 2011 by ERDAS 9.2 GIS with the supervised classiḀcation method and GIS Matrix. ἀe results of the study provide informations of land cover changes into developed area at forest land (11,758.9 ha), shrub (3,337.3 ha), rice Ḁelds (5,977.1 ha), and garden (5,872.4 ha). It has an implication on increasing of the ele-ments of GHGs concentration such as CO2 (14,1 ppm), N2O (5,4 ppb) and CH4 (24,8 ppb). ἀis condition lead to an extreme temperature and presipitation indexs trends in Padang.
Dissertations / Theses on the topic "CO2 and CH4 Leak detection"
1
Segura, Gonzalez David Santiago. "Processus physico-chimiques et impacts environnementaux des fuites de CO2 associé au CH4 lors d’un stockage géologique sur les hydrosystèmes carbonatés proche surface. Approche expérimentale in situ et en laboratoire." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0187.
Full textAbstract:
La prise de conscience de la communauté internationale et la convergence des données scientifiques autour du réchauffement climatique confirment l'urgence de déployer des technologies pour réduire les émissions de gaz à effet de serre. Cependant, ces gaz peuvent s'échapper des réservoirs géologiques profonds et migrer vers les aquifères sus-jacents et la surface. Il est donc nécessaire de mettre en place des systèmes de surveillance du stockage géologique du CO2 pour détecter ces éventuelles fuites et évaluer leur importance et leur impact sur la qualité de l'eau des aquifères. En cas de fuite dans le contexte de réservoirs utilisés pour le stockage du CO2, le CH4 résiduel du réservoir de stockage sera probablement entraîné avec le CO2. Cependant, peu d’études ont abordé les implications de la présence de CH4, et aucune son potentiel en tant que gaz précurseur permettant la surveillance des fuites d’un stockage géologique. L'étude des processus physico-chimiques et des impacts des fuites de CO2 associées au CH4 en cas de fuite sur un aquifère carbonaté proche de la surface nécessite une meilleure caractérisation des processus multi-échelles tels que la dissolution à l'échelle du réseau poreux ou le transport des panaches à l'échelle macroscopique. Les méthodes expérimentales et de modélisation utilisées individuellement donnent des réponses à des questions sur des processus particuliers, mais ces méthodes ont des limites si elles sont utilisées individuellement. Par conséquent, une approche hybride et multi-échelle est nécessaire. Le site expérimental de Saint-Émilion, avec huit forages déjà en place au niveau de l'aquifère de l'Oligocène supérieur, et les expériences passées portant sur les fuites sur les aquifères, offre une excellente opportunité pour une étude multi-échelle expérimentale et de modélisation. Dans cette thèse, l'impact des fuites a été étudié à l'échelle de la carotte en laboratoire, plus spécifiquement sur la compréhension des facteurs contrôlant les processus de dissolution tels que les faciès sédimentaires carbonatés, la vitesse de la nappe, la salinité et de la concentration de CO2. À l'échelle macroscopique, une expérience d'injection d'eau riche en CO2-CH4 a été menée sur le site de Saint-Émilion pour mieux comprendre le comportement physico-chimique du CO2 et du CH4 dans l'aquifère carbonaté. Enfin, les résultats expérimentaux ont été utilisés pour la simulation 3D du transport réactif lors d'un événement de fuite, avec le but de vérifier les résultats expérimentaux et d'étudier les processus de fuite à l'échelle macroscopique dans diverses conditions. Des relations ont été établies entre la cinétique de dissolution des carbonates, la concentration de CO2, le débit d'injection et la salinité. Des liens entre la cinétique de dissolution et l'évolution de la porosité, de la perméabilité, des paramètres électriques et le type de faciès sédimentaire ont été déterminés. L'expérience d'injection sur le site de Saint-Émilion a révélé que : i) certains paramètres physico-chimiques permettent de distinguer la fuite des gaz du signal physico-chimique naturel de l’aquifère ; ii) le déplacement du panache de CO2 est retardé par rapport au déplacement du panache de CH4 ; et iii) la corrélation entre la conductivité électrique et la concentration en CO2 permet de détecter et de suivre une fuite de CO2. De plus, l'approche par modélisation numérique du transport réactif nous a permis d'étudier comment les paramètres de la fuite peuvent modifier la propagation des panaches de CO2 et de CH4 en trois dimensions dans les milieux poreux. La modélisation a également permis d’établir l'influence des interactions de surface sur le transport du CO2 et du CH4. Ces résultats influent directement sur l'élaboration de stratégies efficaces de surveillance et d'atténuation des fuites de CO2 et de CH4 dans les sites de stockage géologiqueThe awareness of the international community and the convergence of scientific data around global warming confirm the urgency of deploying technologies to reduce greenhouse gas emissions. However, these gases can escape from deep geological storage and migrate to the overlying aquifers and the surface. It is therefore necessary to set up monitoring systems for geological CO2 storage to detect these possible leaks and assess their importance and impact on the water quality of the aquifers. In the event of a leak in the context of depleted reservoirs used for CO2 storage, the residual CH4 from the storage reservoir will likely be entrained with CO2. However, few studies have addressed the implications of the presence of CH4, and none have studied its potential as a precursor gas for monitoring leaks from geological storage. Studying the physicochemical processes and impacts of CO2 leakage associated with CH4 in the event of a leak on a near-surface carbonate aquifer requires better characterization of multi-scale processes such as dissolution at the scale of the porous network or the transport of plumes at the macroscopic scale. Experimental and modeling methods used individually give responses to questions on particular processes, but these methods have limitations if used individually. Therefore, a hybrid, multi-scale approach is necessary. The experimental site of Saint Émilion, with eight wells already in place at the level of the Upper Oligocene aquifer, and past experiments on leakage in this aquifer, provides an excellent opportunity for a comprehensive multi-scale experimental and modeling study. In this thesis, the impact of leakage was studied at the scale of the core in the laboratory, more specifically on the comprehension of factors that control the dissolution processes such as carbonate sedimentary facies, groundwater velocity, salinity, and CO2 concentration. At the macroscopic scale, a CO2-CH4-rich water injection experiment was conducted at the Saint-Émilion site to understand better the physicochemical behavior of CO2 and CH4 in the carbonate aquifer. Finally, the experimental results were used for the 3D simulation of the reactive transport during a leakage event, with the aim of verifying the experimental results and studying the leakage processes at the macroscopic scale under various conditions. Relationships between the dissolution kinetics for each CO2 concentration, injection rate, and salinity were established. Links between dissolution kinetics, evolution of porosity, permeability, electrical parameters, and the type of sedimentary facies were determined. The injection experiment at the Saint-Émilion site revealed that : (i) some physicochemical parameters are able to distinguish the gas leakage signal from the natural physicochemical signal of the aquifer; ii) CO2 plume displacement is retarded relative to the CH4 plume displacement; and iii) the correlation between electrical conductivity and CO2 concentration enables detection and track a CO2 leakage. Moreover, the reactive transport modeling approach has allowed us to study how the parameters of the leak can modify the propagation of CO2 and CH4 plumes in three dimensions in the porous media. Modeling also enabled to establish the influence of surface interactions on CO2 and CH4 transport. These findings directly affect the development of effective monitoring and mitigation strategies for CO2 and CH4 leaks in geological storage sites
Book chapters on the topic "CO2 and CH4 Leak detection"
1
McElroy, Michael B. "Natural Gas : The Least Polluting Of The Fossil Fuels." In Energy and Climate. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780190490331.003.0012.
Full textAbstract:
In terms of emissions from combustion, natural gas, composed mainly of methane (CH4), is the least polluting of the fossil fuels. Per unit of energy produced, CO2 emissions from natural gas are 45.7% lower than those from coal (lignite), 27.5% lower than from diesel, and 25.6% lower than from gasoline. As discussed by Olah et al. (2006), humans have long been aware of the properties of natural gas. Gas leaking out of the ground would frequently catch fire, ignited, for example, by lightning. A leak and a subsequent fire on Mount Parnassus in Greece more than 3,000 years ago prompted the Ancient Greeks to attach mystical properties to the phenomenon— a flame than could burn for a long time without need for an external supply of fuel. They identified the location of this gas leak with the center of the Earth and Universe and built a temple to Apollo to celebrate its unique properties. The temple subsequently became the home for the Oracle of Delphi, celebrated for the prophecies inspired by the temple’s perpetual flame. The first recorded productive use of natural gas was in China, dated at approximately 500 BC. A primitive pipeline constructed using stems of bamboo was deployed to trans¬port gas from its source to a site where it could be used to boil brine to produce both economically valuable salt and potable water. Almost 2,000 years would elapse before natural gas would be tapped for productive use in the West. Gas from a well drilled near Fredonia, New York, was used to provide an energy source for street lighting in 1821. The Fredonia Gas Light Company, formed in 1858, was the first commercial entity established specifically to market natural gas. Joseph Newton Pew, founder of the Sun Oil Company (now Sunoco), established a company in 1883 to deliver natural gas to Pittsburgh, where it was used as a substitute for manufactured coal gas (known also as town gas). Pew later sold his interests in natural gas to J. D. Rockefeller’s Standard Oil. The early application of natural gas was primarily for lighting, not only for streets but also for factories and homes.
2
Rafiq, Asma, Misbah Naz, Shehnila Altaf, Saira Riaz, and Shahzad Naseem. "Multifunctional Materials for the Sensing of Gases." In Innovative Multifunctional Nanomaterial for Photocatalysis, Sensing, and Imaging, 128–58. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-8743-3.ch006.
Full textAbstract:
Air contamination and a growing number of harmful gases releasing into the environment is a big issue of present era. Gases like CO, NH3, CO2, SO2, and CH4 can prompt lethal health threats. Gas sensors have attained noteworthy consideration of researchers in monitoring such kind of pollutants. Detection of gases by sensors typically depends upon the sensing properties, like sensitivity, selectivity, response, and recovery time. With the progress of the internet-of-things technology, the uses of gas sensors in the fields of smart homes, wearable gadgets, and smart mobile terminals have developed rapidly. In this chapter, various groups of the sensing materials are outlined thoroughly, comprising gas sensors based on multifunctional materials such as: metals, graphene, cellulose, MXenes, acoustic wave sensors, and catalytic sensors. This chapter also outlines the current accomplishments in the field of gas detection and signifies the current challenges and future outlooks in this field.
3
Belaid, Walid, Amina Houimi, Shrouk E. Zaki, and Mohamed A. Basyooni. "Sol-Gel Production of Semiconductor Metal Oxides for Gas Sensor Applications." In Sol-Gel Method - Recent Advances [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.111844.
Full textAbstract:
As they are widely utilized in industries including the food packaging industry, indoor air quality testing, and real-time monitoring of man-made harmful gas emissions to successfully combat global warming, reliable and affordable gas sensors represent enormous market potential. For environmental monitoring, chemical safety regulation, and many industrial applications, the detection of carbon monoxide (CO), carbon dioxide (CO2), nitrogen dioxide (NO2), and methane (CH4) gases is essential. To reliably and quantitatively detect these gases, much-improved materials and methods that are adaptable to various environmental factors are needed using low-cost fabrication techniques such as sol–gel. The advantages of employing metal oxide nanomaterials-based chemoresistive for creating high-performance gas sensors are shown by key metrics such as selectivity, sensitivity, reaction time, and detection. The primary sensing methods are also grouped and thoroughly covered. In light of the current constraints, anticipated future developments in the field of sol–gel nanomaterial-based chemoresistive gas sensors are also highlighted.
4
Ojha, Varun Kumar, and Paramartha Dutta. "Performance Comparison of Different Intelligent Techniques Applied on Detecting Proportion of Different Component in Manhole Gas Mixture." In Handbook of Research on Computational Intelligence for Engineering, Science, and Business, 758–85. IGI Global, 2013. http://dx.doi.org/10.4018/978-1-4666-2518-1.ch030.
Full textAbstract:
This chapter deals with the comparison of performances of different intelligent techniques for detecting proportion of different component gases present in manhole gas mixture. Toxic gases found in manhole gas mixture are Hydrogen Sulfide (H2S), Ammonia (NH3), Methane (CH4), Carbon Dioxide (CO2), Nitrogen Oxide (NOx), Carbon Monoxide (CO), etcetera. Detection of these toxic gases is essential since these gases influence human health even due to very short exposure. This study is centered on design issues of an intelligent sensory system for detecting proportion of different components in manhole gas mixture and comparison of different intelligent techniques applied for this. The investigation encompasses linear regression based statistical technique, backpropagation algorithm, neuro genetic techniques (using genetic algorithm to train neural network), and neuro swarm techniques (using particle swarm optimization algorithm to train neural network).
Conference papers on the topic "CO2 and CH4 Leak detection"
1
Culp, Jeffrey, Krista Bullard, Ki-Joong Kim, and Ruishu Wright. "Physisorbent-coated fiber optic sensors for near ambient leak detection of CH4 or CO2." In Optical Waveguide and Laser Sensors II, edited by Glen A. Sanders, Robert A. Lieberman, and Ingrid Udd Scheel. SPIE, 2023. http://dx.doi.org/10.1117/12.2665073.
Full text
2
Molie`re, Michel, Philippe Cozzarin, Se´bastien Bouchet, and Philippe Rech. "Catalytic Detection of Fuel Leaks in Gas Turbine Units: 2 — Gas Fuels Containing Hydrogen, Carbon Monoxide and Inert." In ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90290.
Full textAbstract:
The detection of explosive gas and vapors is a critical safety function in Gas Turbines (GT) units. On one hand, this subject is being revisited by the GT community and safety organizations with a main focus on conventional gas fired power units. On the other hand one sees currently an increasing use of alternative primary energies for GT units including both gaseous and liquid fuels such as LPG, naphtha, syngas and a wide series of low and medium BTU gas fuels. This has prompted GE Energy to undertake a comprehensive evaluation of commercial catalytic detectors that are of common use in the detection of gas leaks. In particular, the multiple announcements of coal-based project (IGCC) represented a strong motivation to launch this program that ambitioned to cover both hydrocarbon and non-hydrocarbon fuels, i.e. the largest CnHm/ CO/ H2/ N2(CO2) spectrum. This evaluation program has been jointly devised with and performed by the laboratory of INERIS, a French Institute devoted to safety and environment. Particular emphasis has been placed on the capability to detect combustible species at levels as low as 5% LEL (Lower Explosion Limit) that result from recent safety codes. The overall program has been break down into two parts. The response of catalytic detectors to hydrocarbon gas leaks (natural gases and naphtha vapors) has been addressed in 2004 and the corresponding results have been already published (ASME paper 2005GT68875). This first work phase has shown a satisfactory response of selected catalytic bead sensors towards the hydrocarbon paraffin series up to C8. The second phase (2005) tackled the detection of CH4/ CO/ H2/ N2(CO2) mixtures. In the authors’ knowledge, there was a lack of data in the current literature as to the performances of catalytic detection for this specific class of fuels. A wide range of mixtures was tested to cover the extensive spectrum of medium and low BTU gas fuels, including: “weak natural gas”, coal derived process gas (coke oven, blast furnace gas; COREX gas; etc.) and syngas. CO2 and N2 were used as inert components in concentrations from 20 to 80% vol. This paper summarizes the results of this second evaluation phase. A satisfactory response to the different CH4/ CO/ H2/ N2(CO2) mixtures has been obtained in terms of sensitivity, accuracy and detection limits which satisfies the requirements of current codes and standards. The overall program confirms the possibility to use catalytic bead sensors as a single detection technology for covering virtually all the gas turbine applications, This includes, apart from natural gas: LPG, light distillates (naphtha; gas condensates and NGL), “weak” natural gas, Medium & Low BTU fuels (Coke Oven; Blast Furnace), hydrogen-rich fuels (refinery) and the syngas segments with however the notable exclusion of middle distillates (gasoil, kerosene).
3
Wang, Hu, Michael J. Hamp, Daniel T. Cassidy, An Nguyen, and Mark A. Fritz. "Field Monitoring of Gases Using III-V Semiconductor Diode Laser Technology." In 1998 2nd International Pipeline Conference. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/ipc1998-2101.
Full textAbstract:
III-V semiconductor diode lasers can be used to make accurate measurements of the concentrations of gases. In this paper the field of trace gas detection using III-V semiconductor diode lasers will be reviewed with an emphasis on suitable applications of this technology in pipeline monitoring. III-V semiconductor diode lasers emit light in the near infrared (NIR) with wavelengths ranging from 1 to 2 μm. Many molecules have absorption lines in this spectral range which makes them contenders for detection with diode laser technology. Molecules relevant to the pipeline industry that can be detected using diode laser systems include H2S, C2H4, C2H2, HF, CO2, CO, O2, NH3, HC1, NO, NO2, HCN, H2O and CH4. Diode laser detection systems may be well suited for many pipeline related applications. Portable field-screening detection systems may be possible, such as hand-held systems which can be used to pinpoint leaks for compressor station inspection. Airborne (∼200 km/h) and mobile (∼40 km/h) systems which can be used for pipeline and urban area inspection may also be feasible. Stationary systems can be integrated into pipeline systems to provide real-time remote gas monitoring for Supervisory Control and Data Acquisition (SCADA) systems. Detection sensitivities of parts per million (ppm) or better are achievable for many gases. A single diode laser detector can be designed to detect more than one gas leading to versatile multipurpose systems. As III-V diode laser based gas detection systems exploit the same technologies as the highly successful telecommunications industry they have the potential to be low in cost, reliable, and easy to operate and maintain. We will present an overview of state-of-the-art III-V diode laser detection systems. System performance will be evaluated and the usefulness of these types of detection systems will be demonstrated.
4
Cui, Xiwang, Yong Yan, Lin Ma, Yifan Ma, and Xiaojuan Han. "CO2 leak detection through acoustic sensing and infrared imaging." In THE 2013 UKM FST POSTGRADUATE COLLOQUIUM: Proceedings of the Universiti Kebangsaan Malaysia, Faculty of Science and Technology 2013 Postgraduate Colloquium. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4872118.
Full text
5
Smith, Michael T., and S. H. Wie. "Subsea Environmental Monitoring, Hydrocarbon and CO2 Leak Detection Technologies." In Offshore Technology Conference Brasil. OTC, 2023. http://dx.doi.org/10.4043/32812-ms.
Full textAbstract:
Abstract Among Government Authorities, Subsea Production Operators, and the General Public, there is an increased awareness and concern about subsea hydrocarbons and carbon dioxide (CO2) leaks, and consequent pollution. Leaks from production and CO2 injection wells may have severe environmental consequences. Even if all subsea systems are designed not to leak, leaks have and will occur, in smaller and larger volumes. Any leak, small or big, should be detected and stopped to avoid environmental disasters following the As Low As Reasonably Practicable (ALARP) philosophy as described by Offshore Norway Guidelines 100 for Detection of Acute Pollution to the Sea. Active acoustic sonar has been used for decades in the fishing industry, as a very effective and accurate technology to find fish and monitor marine life. Over the last decade this technology has been further developed to detect hydrocarbon and CO2 leaks from subsea oil and gas production systems. This paper will strive to describe and demonstrate a recently qualified and field validated solution to overcome issues with traditional leak detection methodology, through a collaboration between operators and suppliers and validated through third party testing, both in controlled environments and in real life field installations.
6
Walker, K., A. Posenato Garcia, J. Nunn, and G. Lyman. "CO2 Leak Detection and Conformance Verification Using Borehole Gravity." In SPE Energy Transition Symposium. SPE, 2023. http://dx.doi.org/10.2118/215734-ms.
Full textAbstract:
Abstract Borehole gravity measured from a vertical Carbon Capture and Storage (CCS) injection well, or nearby observation well, provides a cost-efficient solution for monitoring the reservoir for CO2 flow and the overburden for leaks. In this paper, two CO2 injection reservoir models using piston flow and Buckley-Leveret theory are built to simulate and evaluate surface and borehole gravity signatures associated with CO2 flow through thin and thick reservoirs in deep and shallow scenarios. The sensitivity of gravity to plume parameters is also analyzed. The results demonstrate that the lateral gradient in vertical surface gravity after a year of injection is effective for monitoring shallow reservoirs over relatively long time periods and ineffective for deep reservoirs. However, borehole gravity after only a few months of injection is sensitive to both time-lapse density variations and the lateral extent of the saturation plume in all reservoir thickness and depth scenarios. A competition exists for the dominant parameter controlling the borehole gravity signal between density contrast and plume radius. At the bottom of the borehole above the reservoir, sensitivity is dominated by density contrast. As one ascends the borehole, the distance to the reservoir below increases, which lowers the gravity while increasingly adding contributions to the vertical component of gravity, resulting in the plume radius becoming the most sensitive parameter. It is shown that this enhanced sensitivity enables inversions of borehole gravity, using weighted damped least squares, to sufficiently image the radial variation in density contrast associated with the CO2 plume. Analysis of survey parameters on inversion accuracy shows the benefit of conducting surveys that penetrate the reservoir. The results also show that while surface gravity is not capable of seeing small leaks, borehole gravity can detect the depth of leaks within hundreds of feet from a wellbore by a distinctive cross over along the gravity profile. The estimated plume radius based on a reservoir filling model and the comparison of that predicted smooth gravity profile to the observed profile that is sensitive to leak cross-overs in the confining zone provides a cost-effective measurement that can trigger higher cost surveys for deeper levels of investigation.
7
Magoarou, C. Le, E. Schissele-Rebel, and P. Thore. "4D Seismic Modelling Applied to CO2 Leak Detection: Sensitivity Analysis - Part A." In 1st Geoscience & Engineering in Energy Transition Conference. European Association of Geoscientists & Engineers, 2020. http://dx.doi.org/10.3997/2214-4609.202021056.
Full text
8
Le Magoarou, C., E. Schissele-Rebel, M. Boisson, S. Bakthiari, and M. Jazayeri Noushabadi. "4D Seismic Modelling Applied to CO2 Leak Detection : 3D Case Study - Part B." In 1st Geoscience & Engineering in Energy Transition Conference. European Association of Geoscientists & Engineers, 2020. http://dx.doi.org/10.3997/2214-4609.202021058.
Full text
9
Bohren, A., and M. W. Sigrist. "Laser Spectrometer Based on Optical Parametric Oscillator for Trace Gas Detection in Multicomponent Mixtures." In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/cleo_europe.1996.cwh3.
Full textAbstract:
The selective and sensitive detection of trace gases in multicomponent gas mixtures by means of absorption spectroscopy requires narrowband continuously tunable laser sources. Newly available optical parametric oscillators (OPO) meet these requirements almost perfectly. Our commercial nanosecond OPO - system is pumped by the third harmonic of a Nd:YAG laser and offers a tuning range from 440 to 1800 nm. The linewidth of less than 0.2 cm–1 at energy levels of several mJ per pulse is maintained over the whole tuning range. At standard pressure the absorption linewidths of most environmental relevant trace gases such as CO2, CH4 and volatile organic compounds (VOC's) match with the laser linewidth thus making the system particularly useful for the analysis of ambient air samples. First experiments with a specially designed nonresonant photoacoustic cell on CO2 and CH4 overtones in the idler range of the OPO (710 - 1800 nm) demonstrate the power of this approach. An example is shown in Fig. 1 for CO2.
10
Harati, Saeed, Sina Rezaei Gomari, Mohammad Azizur Rahman, Rashid Hassan, Ibrahim Hassan, Ahmad K. Sleiti, and Matthew Hamilton. "Enhancing Safety in Geological Carbon Sequestration: Supervised Machine Learning for Early Detection and Mitigation of CO2 Leakage in Injection Wells." In International Petroleum Technology Conference. IPTC, 2024. http://dx.doi.org/10.2523/iptc-23737-ea.
Full textAbstract:
Abstract The efficient and safe operation of CO2 injection wells during geological sequestration is crucial for successful carbon capture and storage (CCS) projects. This study explores the application of machine learning in creating a data-driven model for simultaneous prediction of the location and size of potential leak incidents along an active CO2 injection well based on wellhead and bottom-hole pressure and temperature data. Five different well-established machine learning algorithms were selected for predictive model development, including Support Vector Regression (SVR), K-Nearest Neighbor Regression (KNNR), Decision Tree Regression (DTR), Random Forest Regression (RFR), and Artificial Neural Network (ANN). A series of numerical simulations were performed to create a dataset based on a CO2 injection well model in a southern North Sea saline aquifer reservoir, accounting for various leak scenarios with different locations and sizes. The dataset includes three input features of wellhead pressure, bottom-hole pressure, and bottom-hole temperature, paired with two output variables of leak location and leak size. The research findings demonstrate that all models perform well in effectively pinpointing leak locations, but they face difficulties when it comes to detecting small leaks, particularly those with a CO2 leakage rate below 0.01 kg/s. The results obtained indicated that, with regard to model performance, the SVR and KNNR models tended to outperform the others during the testing phase. More precisely, the SVR model demonstrated exceptional performance in the context of leak localization, particularly when dealing with smaller datasets. Conversely, KNNR consistently showcased superior performance in the detection of leak size, regardless of the dataset size. The outcomes of this research can provide valuable insights into the behavior of leaky CO2 injection wells during geological sequestration and highlight the efficacy of supervised machine learning in detecting and predicting leakage in CO2 injection wells.
Reports on the topic "CO2 and CH4 Leak detection"
1
LaFleur, Carolyn, Amanda Harmon, and James Rutherford. PR-004-213900-Z01 Existing and Emerging Technologies in Methane Leak Detection and Quantification. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), January 2023. http://dx.doi.org/10.55274/r0012252.
Full textAbstract:
Methane (CH4), the main component of natural gas, has a global warming potential 25 to 36 times more potent than carbon dioxide (CO2) over 100 years. Methane emissions are often intermittent and highly variable, a multivariate phenomenon of flow rate, time, and conditions. Cost-effective technologies are needed to detect, locate, and measure methane gas leaks faster and more efficiently. There is a diverse array of existing and emerging technologies capable of detecting, locating, and quantifying methane emissions. Broadly termed leak detection and quantification (LDAQ), these technologies vary in capability, application, and cost. This report provides includes LDAQ technology descriptions and applications. Existing and emerging technologies available for methane LDAQ are identified and characterized in an Assessment Framework that incorporates a Technology Assessment and a Market Assessment. These comprise the LDAQ Technology Assessment Tool (in Excel workbook format) that accompanies this report and is described herein.
2
Tossey, Brett, and Ramgopal Thodla. PR-180-094506-R01 Challenges for Safe and Reliable On-Shore Pipeline Transport of Supercritical CO2. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), September 2010. http://dx.doi.org/10.55274/r0010712.
Full textAbstract:
There is interest within the pipeline industry in transporting supercritical CO2 in pipelines. A significant issue is the lack of an independent industry standard for supercritical CO2 pipelines. Existing industry standard for liquid and gas transmission are used for mechanical design requirements, but selected properties of supercritical CO2 make it a unique product. Impurities in the gas steam, materials selection, and leak detection in supercritical CO2 require special consideration. The objective of this project is to engage the supercritical CO2 industry in a workshop and use their knowledge to complete a gap analysis. The project is divided into two main thrusts; survey of knowledge and gaps by conducting an industry workshop (Thrust 1) and to outline what efforts and work is needed to close these gaps in a limited way (Thrust 2). This report summarizes the results of both thrusts. This report summarizes the results of the gaps analysis. The primary finding is that the supercritical CO2 pipeline operators in the United States are confident that the designs of their transmission systems are safe and adequate. Another important finding was the need for improvement in the equation of state (EOS). Currently, most models fail to accurately predict the affects of coal combustion impurities on the phase behavior of supercritical CO2. Improvements in metering technology, materials selection criteria, and leak detection were also identified as gaps. The final gap that was identified was the need for a standardized �blow-down� procedure during system startup and shutdown. An industry standard specific to supercritical CO2 transportation should include sound engineering guidance covering each of these gaps. See the associated linked documents for appendices to this report.