Helium In Gases Research Articles

GEOLOGICAL AND STRUCTURAL MODELS OF FORMATION AND ACCUMULATION OF GAS IN MAN-MADE RESERVOIRS OF COAL ROCK MASSIVES

The formation of technogenic reservoirs of coal-rock massifs is determined by the depth of development, lithological features of the host rocks and the gas content of the coal-rock massif. The formation and redistribution of gas-saturated zones and migration routes in coal-rock massifs continues even now, which is associated with modern fluid migration. Gas, filling the mine workings of closed mines, creates a threat to communications, structures as a result of explosions and has a negative impact on human health.
 It has been established that the regular distribution of gaseous hydrocarbons is determined by discontinuities and confirms not only the diffusion gas saturation of the massif, but also the tempo, that is, the gas saturation of the massif through discontinuities during tectonic (tectonic-magmatic) activations. At the same time, it should be noted that geological discontinuities were not the “transport arteries” of gaseous hydrocarbons not throughout the entire space. For most of its strike, coal and rocks in the zones of discontinuities are folded, and there is almost no gas transmission. The worked-out space of active mines is a new technogenic reservoir suitable for the accumulation of gaseous hydrocarbons, the thickness of which exceeds the thickness of the coal seam. The active processes of gas migration in the exhaust space are indicated by the study of the residual gas component, in the mixture of which helium, hydrogen and quantitative changes in hydrocarbon gases (C2 - C6) were found.

Identification and classification of the flow pattern of hydrogen-air-steam mixture gas under steam condensation

Under the severe accident of the nuclear reactor, the strong coupling phenomenon exists between the transport and condensation of the steam-air-hydrogen multi-component gas in the containment atmosphere. Under this coupling effect, the flow patterns of mixture gas induced by condensation are critical to hydrogen accumulation risk assessment. The general flow characteristics of typical flow patterns were qualitatively predicted and confirmed in our previous work. However, the transient mass transfer process of multicomponent gases is complex, and flow pattern transitions are difficult to be captured. To further clarify these contents, experiments and corresponding numerical simulations are combined in the present work. The formation mechanism of the typical flow patterns is further revealed. The flow pattern transition boundaries of the mixture are quantified based on more data in confirmatory experiments. Experiments are performed under wider wall sub-cooling (ΔT = 60–110 °C) and wider range of steam concentration (Xsteam) from 16% to 90%, the volume concentration of helium in non-condensable gases (XHe/XNon) ranges from 10% to 70%. Results show that the homogeneous downward flow is generally formed when XHe/XNon < 40%. Under medium helium concentration (XHe/XNon: 42%–55%), when Xsteam > 30%, the flow pattern of the mixture gas is the separation flow. Under high helium concentration (XHe/XNon > 55%), the flow pattern of the mixture gas is the homogeneous upward flow when Xsteam > 20%. Furthermore, the empirical component correlations to classify the three flow patterns are proposed for the first time. Correlations and numerical simulation have good consistency in the prediction of flow patterns under most component conditions.

Degradation of condensation heat transfer on a vertical cylinder by a light noncondensable gas mixed with air-steam mixtures

In this study, the experimental investigation result of steam condensation on a vertical tube in the presence of air and a light noncondensable gas is presented. This study aims at elucidating the effect of hydrogen that may be generated during the progression of a severe accident on the condensation heat transfer. Using helium as a simulant of hydrogen, a series of condensation tests were performed. A novel helium measurement system was introduced to analyze the composition of mixture gas. The condensation heat transfer coefficient was obtained under natural convection conditions on a 1 m long condenser tube having an outer diameter of 21.5 mm. A comprehensive experimental database was obtained to understand the parametric effect of the total mass fraction of noncondensable gases, molar concentration of helium in noncondensable gases, and wall subcooling degree. An empirical correlation for the degradation factor to account for the effect of a light noncondensable gas was proposed for application to the condensation model for the steam–air mixture based on the experimental data. The strategy to adopt the degradation factor was assessed against three steam–air–helium condensation tests.

Forced convection condensation of steam in the presence of multicomponent noncondensable gases inside a horizontal tube

An experimental investigation on condensation heat transfer characteristics of steam in the presence of multicomponent noncondensable gases in a horizontal tube is conducted in the present research. The experimental runs are carried out at a volume ratio of helium and noncondensable gases varying from 0% to 90%, the mixture gases pressure between 0.13 and 0.2MPa, over the mixture gases velocity changing from 8 to 34m/s, covering all the major flow patterns inside a pipe. The effects of inner wall subcooling, mixture gases velocity and pressure on local heat transfer coefficient have been analyzed for annular, wavy and stratified flow. The change of the condensation heat transfer capacity for different volume ratios of helium in the noncondensable gases have been studied at the same time. The results indicate that the local heat transfer coefficient increases with the increasing wall subcooling for annular and wavy flow but decreases for stratified flow. With the flow regime transforming from annular to stratified flow, the active influence of the gases velocity is gradually weakened and the local heat transfer coefficient even starts to decrease when it reaches stratified flow. For all flow patterns, the increases of helium volume fraction and mixture gases pressure always enhance the condensation heat transfer. Based on the experimental analysis, an empirical correlation for predicting the local heat transfer coefficient is proposed. The comparison of the calculated results and the experimental data shows that the present correlation can give satisfactory engineering accuracy.

In Response.

Noll et al.1 remind the reader that intraperitoneal (IP) gas composition may be significantly affected by alveolar gases.2 Concerns for both combustion and embolic phenomena dictate safe laparoscopic practice. Regardless of the inspired gas mixture, the IP gases reflect those delivered from the alveoli through the blood to the peritoneum as well as the continuous replacement of the insufflation gas delivered by a pressure limit device. The ideal composition of IP gases remains to be determined. A recent Cochrane database3 could not establish the relative safety of carbon dioxide (CO2), helium, and nitrous oxide (N2O) in laparoscopic gases. Helium afforded greater hemodynamic stability in low-risk patients, and N2O appeared to confer a degree of analgesia over CO2. In this study, no mention was made of the potential for combustion, which exists most markedly for gas mixtures containing high concentrations of oxygen (O2). Although combustion is possible in the presence of bowel gases such as hydrogen and methane when N2O is present, the clinical significance of this finding is yet to be established. It is to be noted that the time to equilibrium of IP fN2O in the study by Diemunsch et al.2 in 2000 was >8 hours during ventilation with inspired fN2O = 0.66 and that fN2O at 2 hours was 0.29, suggesting that in most cases, the fN2O in peritoneal gases is insufficient to increase ignition hazards. It is the normative practice at our institution to use an inspired gas mixture of air and O2 during laparoscopic procedures, which explains why N2O was not detected in any of our samples. This is not necessarily the case in other institutions, and in many parts of the world, O2 is the only gas available, although nitrogen remains present when an extractor is used as the O2 source. In circumstances in which compressed air is not available as a component of inspired gas, using N2O as a diluent for O2 reduces, but does not eliminate, the potential for combustion, especially during electrocautery and inadvertent release of bowel gases. As noted by Noll et al.,1 in the presence of hydrogen and methane, N2O facilitates combustion.4 Both our study and those referenced by Noll et al. inform the practitioner that the mixture of gases present during laparoscopy represent a balance created by those delivered from the body and the insufflation device and reflect their physical properties, notably perfusion and blood-gas solubility characteristics. The composition of peritoneal gases is dynamic, and efforts to maintain a high level of CO2 during procedures are critical to patient safety. Both gas analysis and venting of the pneumoperitoneum5 will contribute to achieving IP gas concentrations delivered by the insufflation apparatus as intended by the practitioner. Susan P. Taylor, MD, MPH Department of Anesthesiology Children’s Hospital of Wisconsin Medical College of Wisconsin Milwaukee, Wisconsin [email protected] George M. Hoffman, MD Anesthesiology and Pediatrics Children’s Hospital of Wisconsin Medical College of Wisconsin Milwaukee, Wisconsin

Chemical and isotopic characteristics and origin of spring waters in the Lanping–Simao Basin, Yunnan, Southwestern China

The chemical and isotopic characteristics (oxygen, hydrogen, and strontium) of spring waters and isotopic compositions of helium (He) and neon (Ne) in gases escaping from spring waters in the Lanping–Simao Basin are studied. A total of twenty-one spring water samples (twelve hot springs, four cold springs, and five saline springs) and eleven gas samples were collected from the study area, including one spring and one gas sample from northern Laos. It is found that saline spring waters in the study area are of chloride type, cold spring waters are of carbonate type or sulfate type, and hot spring waters are of various types. High total dissolved solids levels in saline springs are significantly related to Upper Cretaceous–Paleocene salt-bearing strata. On the basis of hydrochemical geothermometry, the reservoir temperatures (Tr) for hot springs, cold springs, and saline springs are 65.5–144.1, 37.8–64.4, and 65.1–109.0°C, respectively, and the circulation depths of saline springs are much larger than those of hot and cold springs. The oxygen and hydrogen isotopic compositions of springs in the Lanping–Simao Basin and northern Laos are primarily controlled by meteoric waters with obvious latitude and altitude effects, and are also influenced by δ18O exchange to some extent. Most Sr2+ in spring waters of the study area is derived from varied sources (carbonate, evaporite, and silicate mineral dissolution), and the Sr isotopic compositions are greatly influenced by volcanic rocks. Wide distribution of crust-derived He in the Lanping–Simao Basin and northern Laos reveal that faults in these areas may not descend to the upper mantle. It is concluded that water circulation in the study area may be limited above the upper mantle, while saline springs may originate from the Upper Cretaceous–Paleocene evaporites. Hydrochemical characteristics demonstrate affinities among the Lanping–Simao Basin, northern Laos, and Yanjing, eastern Tibet, while disaffinities are observed between these areas and Tengchong on the basis of the hydrochemical characteristics and noble gas isotopic compositions.

Characteristics of noble gases in the large Gaoshiti-Moxi gas field in Sichuan Basin, SW China

Abstract Taking the large Gaoshiti-Moxi gas field of Sichuan Basin as an example, the total composition contents and isotopes of noble gases in the natural gases from the Sinian Dengying Formation and Cambrian Longwangmiao Formation are analyzed, and then their geneses are identified. The content value of helium in the natural gases of the large Gaoshiti-Moxi gas field is generally 1-2 orders of magnitude higher than that of air, and the average content in the second member of the Dengying Formation is 512×10−6, reaching the industrial utilization standard. The content values of Neon, Argon, Krypton and Xenon are relative low, lower than the corresponding content value in air. The total composition contents of noble gases in the natural gas of the large Gaoshiti-Moxi gas field gradually reduce in the sequence of the second member of Dengying Formation, the fourth memeber of Dengying Formation, and Cambrian Longwangmiao Formation. The noble gases 3He/4He value in the natural gases of the large Gaoshiti-Moxi gas field is in 10−8 order of magnitude, the 40Ar/36Ar value is usual from 1 024 to 9 559, 132Xe is relatively surplus and 129Xe is relatively loss. The comprehensive genetic identification of Helium, Argon, Xenon indicates that the noble gases in the large Gaoshiti-Moxi gas field are typical crustal source genesis, and the study area has stable tectonic background and does not have active deep fractures or mantle connecting fractures.

Gases from mud volcanoes of western and central Caucasus

AbstractNew data on He and C isotopes in gases from Caucasus mud volcanoes located in Taman Peninsula (TP, Russia) and Kakhety District (KD, Georgia) have been produced and included in a wider metadata‐set, allowing a comparison between gas geochemistry of the two regions. In TP, the 3He/4He (R) ratios are typical of radiogenic crustal helium (R/Ratm ∼ 0.03, on average). In KD, the helium isotopic ratio Rmax = 223 × 10−8 (R/Ratm = 1.59) indicates an admixture of mantle‐derived helium in gases from the central segment of the Caucasus. The repeated sampling showed that the 3He/4He values in both TP and KD mud volcano emanations are effectively constant through time, unlike δ13C values in accompanying CH4 and CO2. Moreover, δ13C values in these gases show lateral variations within the limits of volcanic edifice. Positive correlations found between the pairs (3He/4He)meas–(4He/20Ne) and (3He/4He)corr–[He] suggests that there are two helium end‐members in KD gases representing ‘near‐surface’ and ‘deep‐originated’ components. There is no correlation between methane and mantle‐derived helium in Caucasian mud volcano gases. CH4 and radiogenic helium are generated in Cenozoic molasse sequences that fill structural depressions.

ChemInform Abstract: Helium Production During the Electrolysis of D2O in Cold Fusion Experiments.

We report the results of experiments designed to detect helium in the effluent gases from electrolysis reactions at palladium cathodes while rigorously excluding possible helium contamination from other sources

Variations of helium and radon concentrations in soil gases from an active fault zone in southern Taiwan

Systematical analysis of soil-gas compositions was performed in the National Pingtung University of Science and Technology (NPUST) campus in southern Taiwan. The results show that the anomalous sites for helium, radon, nitrogen and carbon dioxide concentrations coincide with the surface trace of geological and geomorphological characteristics of the active Chaochou Fault. Some of these sites were chosen for soil helium and radon gas continuous monitoring at the suspected fault scarp. During a consecutive measurement for several months, a striking feature is that anomalously high concentrations appeared to be spike-like a few hours to a few days before the earthquakes. This result suggests that the variations in soil-gas compositions along the Chaochou Fault may reflect the regional crustal stress/strain changes prior to earthquakes.

Radon and helium in soil gases at Cañadas caldera, Tenerife, Canary Islands, Spain

The spatial distribution of soil radon was investigated at Cañadas caldera, Tenerife, in two surveys carried out in the summers of 1992 and 1995 by using α-particle-sensitive cellulose nitrate films (Track-Etch) and emanometry, respectively. Soil helium was studied at several transects crossing different structural features of the area. Radon concentration measured by Track-Etch ranged from 1.0 to 1990 pCi/l while that measured by emanometry ranged from 0.1 to 618 pCi/l. Soil helium concentration varied from 5250 to 15 560 ppb with an average value of 6197 ppb. The spatial distribution of soil radon correlates quite closely with structural features (fractures, emission centers, etc.), where the main geothermal manifestations (fumaroles, steam ground and high subsurface temperature and gas contents) also occur. Areas showing high soil Rn concentrations occur at the summit of Teide, Roques de Garcı́a, caldera rim and south and east off side of the caldera. High soil helium anomalies correlate well spatially with those of radon, especially at the summit of Teide where relatively high 3He/ 4He isotopic ratios occur, suggesting a deep contribution for these emanations. Data indicate that radon and helium are supplied mostly from a deep source, with a minor contribution from U- and Th-rich shallow rocks and soils.

ABSTRACT: Nitrogen and Helium in Natural Gases: Identifying the Risk Factors from a Noble Gas Study of the Hugoton Panhandle Giant gas Field

ABSTRACT: Nitrogen and Helium in Natural Gases: Identifying the Risk Factors from a Noble Gas Study of the Hugoton Panhandle Giant gas Field

Mantle-Derived Methane Homologue, Carbon Dioxide and Helium in Natural Gases from Songliao Basin, China

Whether abiogenic (inorganic) actions can form petroleum and natural gas reservoirs has been a debatable problem for over a century in the academy circle. Gold (1979) proposed deep-earth gas hypothesis. Wang (1983, 1989, 1997) discussed the geochemical characteristics of deep-earth gas. Jenden et al. (1993) proposed three specific analytical criteria to identify mantle-derived hydrocarbons in oil and gas field. The isotopic composition characteristics of methane homologue, carbon dioxide and helium in natural gases from Songliao Basin, China will be discussed in this paper.

Mantle-derived helium and carbon in groundwaters and gases of Mount Etna, Italy

We report the first detailed investigation of both helium and carbon isotopes in groundwaters and gases of Mt. Etna, providing new insight into the distribution, origin and budget of magmatic gas release at this very active volcano [1]. A mantle-derived magmatic component, with ultimate 3He/ 4He ratio of 6.9 ± 0.2 R a and δ 13C of about −4‰, is identified in both types of fluids, depending on their location and the extent of their dilution by either air (gases) or a mixture of dissolved air and organic carbon (waters). Apart from the summit zone, this magmatic component is preferentially concentrated in CO 2-rich groundwaters that issue from two remote sectors of the south-southwest and eastern volcano flanks, where its proportion increases with the altitude of meteoric recharge (or the length of pathflow) of the waters. Such a pattern suggests that, in addition to possible local gas input, the groundwaters collect much of their dissolved magmatic He and C while they infiltrate and flow through one of the more elevated, gas-effusing parts of the volcanic pile, among which the south-southeast fracture zone of Etna is the best candidate. These observations provide a new framework for remote geochemical monitoring of the volcano. The 3He/ 4He ratio of the magmatic gas end-member coincides with that of helium trapped in the He-rich olivine crystals of Etna basalts (mean range: 6.7 ± 0.4 R a, [2,3]), pointing to its negligible dilution by radiogenic He from the crustal basement and further constraining the 3He/ 4He ratio of the present-day Etna magma. While being lower than the typical MORB value of 8 R a, this ratio is the highest for an active volcano in continental Europe and probably tracks a relatively radiogenic upper mantle zone that is upwelling beneath this region [4]. The estimated outputs of mantle-derived CO 2 and 3He from Etna account for 10% and 15%, respectively, of estimates for global subaerial volcanic emissions. This huge contribution results from continuous degassing of mostly unerupted He- and C-rich alkaline basaltic magma, which occurs principally through the central open conduits and secondarily through the flanks of the volcano. Groundwaters carry only a minor fraction (≈ 3%) of total emitted CO 2 and 3He.

Isotopic Correlation of Helium, Argon, Nitrogen and Carbon in Natural Gases: ABSTRACT

Isotopic Correlation of Helium, Argon, Nitrogen and Carbon in Natural Gases: ABSTRACT

Evidence of terrestrial discharge of deep groundwater on the Canadian Shield from helium in soil gases

Assessment of the impact of deep geological disposal of nuclear fuel wastes at a site in the Canadian Shield requires knowledge of the location and size of areas of discharge of deep groundwater from the vicinity of the underground disposal vault. A strong He anomaly has been detected in soil gases in a 10 X 10 m area of wetland on the banks of Boggy Creek, near Lac du Bonnet, Manitoba. The area has He concentrations in near-surface soils as high as 360 nL[center dot]L[sup [minus]1] and is assumed to indicate discharge of He-rich groundwater through a permeable subsurface bedrock fracture. Elevated Cl[sup [minus]] concentrations in groundwater and its use as a [open quotes]deer lick[close quotes] support this interpretation. A He flux density of [approximately] 2.1 L[center dot]m[sup [minus]2][center dot]a[sup [minus]1] is determined from a depth profile of He concentrations at one location in the site. A total He flux of 270 L[center dot]a[sup [minus]1] is determined for the entire site, which corresponds to a deep groundwater discharge of about 26 000 L[center dot]a[sup [minus]1]. This estimate is comparable with He fluxes and calculated groundwater discharges for two other lake-bottom locations on the Canadian Shield. 26 refs., 6 figs., 1more » tab.« less

3He/4He ratios and heat flow in the continental rift-valley, eastern China

Heat flow and the origin of helium in natural gases from fault basins of the continental rift-valley in eastern China are discussed in terms of helium isotope geochemistry.3He/4He ratios in natural gases from the rift-valley range from 2.23 × 10−7 to 7.21 × 10−6, which are directly proportional to the concentration of helium and ΣNHC/ΣHC ratio in natural gases. Geological and isotope geochemical data suggest that helium in natural gases consists predominantly of crustal radio-genic and upper mantle-derived helium. In a simple mixing pattern between crustal He and mantle-derived He, mantle-derived helium in natural gases would account for 10–60%. Calculated values for heat flow (Q) range from 59.7 to 82.4mWm−2, of which about 60 percent in the rift-valley is derived from the upper mantle. Natural helium reservoirs would be found in the areas where the upper mantle uplifted greatly and heat flow is large in the continental rift-valley.

Helium production during the electrolysis of D 2O in cold fusion experiments

We report the results of experiments designed to detect helium in the effluent gases from electrolysis reactions at palladium cathodes while rigorously excluding possible helium contamination from other sources

Radon and helium in soil gases in the Phlegraean Fields, central Italy

The distribution and migration of radon and soil‐gas concentrations in the Phlegraean Fields, Italy, are controlled by the tectonic features of the area. Radon is supplied from surficial sources and helium has both surficial and deep origins. There is no direct correlation between the two noble gases on a point‐to‐point basis but the areal distribution of both gases is similar, suggesting that the distribution is controlled primarily by fractures and movement of geothermal fluids.

Effect of moisture and carbon dioxide on concentrations of helium in soils and soil gases

Helium is often measured in exploration programs, either in interstitial soil gases collected by hollow probe or in gases desorbed from pore spaces of soil samples. However, measured helium concentrations are affected by various parameters that must be considered when interpreting data, including the variation in concentration of other soil gases. The effects of moisture and carbon dioxide in the soil are particularly important. This study compares helium concentrations with soil moisture and carbon dioxide contents of soil and soil gas samples collected in several areas. Where soil moisture was below about 4% by weight, helium concentrations in soil gases collected by hollow probe correlated well with helium concentrations desorbed from soil at the same site. Measured helium concentrations were significantly reduced, however, in areas where soil moisture was greater than 10% and were below the concentration of helium in air in areas where soil moisture exceeded 18%. Carbon dioxide content of the samples also affects helium concentrations. Helium concentrations were significantly reduced in samples where the carbon dioxide content exceeded 1% by volume of the gas sample.