Methane (CH4) is only a trace constituent of the atmosphere but an important greenhouse gas. Although groundwater is unlikely to be a major source of atmospheric CH4, its contribution to the CH4 budget of the UK has up to now been poorly characterised. Groundwater CH4 concentrations have been measured on 85 samples from water-supply boreholes and a further eight from other miscellaneous water s...

in this study, it was shown that how co2 and h2s were removed from a natural gas stream, using a nanofluid containing nanoporous graphene in diehanolamine (dea). before running the experiments, the appropriate values were chosen for the nanosheet dosage and the liquid and gas flow rates in the absorption experiments, which were performed in a laboratory scale wetted wall column. in the experime...

Horizontal drilling and hydraulic fracturing have enhanced energy production but raised concerns about drinking-water contamination and other environmental impacts. Identifying the sources and mechanisms of contamination can help improve the environmental and economic sustainability of shale-gas extraction. We analyzed 113 and 20 samples from drinking-water wells overlying the Marcellus and Bar...

    In this study, it was shown that how CO2 and H2S were removed from a natural gas stream, using a nanofluid containing nanoporous graphene in Diehanolamine (DEA). Before running the experiments, the appropriate values were chosen for the nanosheet dosage and the liquid and gas flow rates in the absorption experiments, which were performed in a laboratory scale wetted wall column. In the expe...

Landfills are the largest sources of methane (CH4) emissions to the atmosphere in the United States. However, few measurements of whole landfill CH4 emissions have been reported. Here, we present the results of a multi-year study of whole landfill CH4 emissions using atmospheric tracer methods at the Nashua, New Hampshire Municipal landfill in the northeastern United States. Emissions were meas...

The volumetric changes in the coal matrix (Coal Shrinkage), permeability under various gas environment conditions as well as perographical properties were studied in the laboratory. The shrinkage and permeability of coal were examined with respect to changing gas type and confining pressures. The shrinkage tests were carried out in high-pressure bombs while the permeability study was conducted ...

There is increasing interest in the measurement of methane (CH4) emissions from tree stems in a wide range of ecosystems so as to determine how they contribute to the total ecosystem flux. To date, tree CH4 fluxes are commonly measured using rigid closed chambers (static or dynamic), which often pose challenges as these are bulky and limit measurement of CH4 fluxes to only a very narrow range o...

The structures of carbon nanotubes grown from catalytic nanoparticles via plasma-enhanced chemical vapor deposition in CH4 /H2 mixtures show a strong dependence on the H2-to-CH4 ratio in the feed gas. A suite of characterization techniques, including optical emission, infrared, and Raman spectroscopies combined with convergent-beam and selected-area electron diffraction, and high-resolution sca...

[1] Huge quantities of CH4 are stored in marine sediment in the form of methane hydrate, bubbles, and dissolved CH4 in pore water. Here I discuss the various pathways for methane to enter the ocean and atmosphere, including: (i) Methane hydrate dissolution or dissociation as it rises through seawater. The dissociation rate can be 2 to 3 orders of magnitude greater than the dissolution rate. (ii...

Global stream and river greenhouse gas emissions seem to be as large as the oceanic C uptake. However, stream and river emissions are uncertain until both spatial and temporal variability have been quantified. Here we investigated in detail the stream CH4 and CO2 emissions within a hemiboreal catchment in Southwest Sweden primarily covered by coniferous forest. Gas transfer velocities (k600), C...