Dissolved gas analysis (DGA) is a reliable technique for detecting the presence of incipient fault conditions in oil immersed transformers. In this method the presence of certain key gases is monitored. The various analysis methods are : Rogers ratio, IEC ratio, Doernenburg, Duval triangle, key gas, artificial neural network (ANN) method. In this paper the various DGA methods are evaluated and ...

Methane (CH4) emission, which is mainly produced during normal fermentation of feeds by the rumen microorganisms, represents a major contributor to the greenhouse gas (GHG) emissions. Several enteric CH4 mitigation technologies have been explored recently. A number of new techniques have also been developed and existing techniques have been improved in order to evaluate CH4 mitigation technolog...

Manure composting is a significant source of atmospheric methane (CH4) and nitrous oxide (N2O) that are two potent greenhouse gases. The CH4 and N2O fluxes are mediated by methanogens and methanotrophs, nitrifying and denitrifying bacteria in composting manure, respectively, while these specific bacterial functional groups may interplay in CH4 and N2O emissions during manure composting. To test...

The electrochemical sensor for detecting hydrogen sulfide was fabricated. H2S gas molecules pass through polytetrafluoroethylene membrane with 0.22 mm pore size. Carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) were used to fabricate working and counter electrodes. It can be seen from Field Emission Scanning Electron Microscopy (FESEM) images of the working electrode that...

A low pressure carbon molecular sieve (CMS) membrane based process to upgrade biogas from anaerobic digestion of agricultural waste to a substitute natural gas (SNG) has been tested on a pilot scale. The data extracted from the pilot plant was used to estimate membrane permeance and ideal selectivity of the CO2/CH4 gas pair. Four semi-commercial modules were tested. The results show that by usi...

We present ISO SWS (AOT6) observations of the protostellar object RAFGL 7009S. This source is particularly interesting for the characterisation of chemistry arising from grain surfaces andmantles, since the solid state features ofmany simple molecules such asH2O,CO,CO2, CO2 andCH4 are detected, together with weaker features not yet unambiguously identified. Gas phase H2O, CO2, CH4 and CO can al...

Research was conducted to evaluate the feasibility of producing methane gas from combined segregated municipal and agricultural waste. The combination of the two wastes resulted in sufficient nutrient value and bacterial diversity to improve the biodegradability of cellulose and increase the efficiency of gas production from the combined wastes. The feedstock included municipal solid waste with...

Inland lakes play important roles in water and greenhouse gas cycling in the environment. This study aims to test the performance of a flux-gradient system for simultaneous measurement of the fluxes of water vapor, CO2, and CH4 at a lake-air interface. The concentration gradients over the water surface were measured with an analyzer based on the wavelength-scanned cavity ring-down spectroscopy ...

[1] Tropical East African Lake Tanganyika hosts the Earth’s largest anoxic freshwater body. The entire water column holds over 23 Tg of the potent greenhouse gas methane (CH4). Methane is formed under sulphate poor conditions via carbon dioxide reduction or fermentation from detritus and relict sediment organic matter. Permanent density stratification supports an accumulation of CH4 below the p...

Ruminant-derived methane (CH4), a potent greenhouse gas, is a consequence of microbial fermentation in the digestive tract of livestock. Development of mitigation strategies to reduce CH4 emissions from farmed animals is currently the subject of both scientific and environmental interest. Methanogens are the sole producers of ruminant CH4, and therefore CH4 abatement strategies can either targe...