Natural gas sources

The reason for the popularity of anhydrous ammonia is its economy. No further processing is needed and it has a very high (82.2%) nitrogen content. Additionally if held under pressure or refrigerated, ammonia is a Hquid. Being a Hquid, pipeline transport is practical and economical. A network of overland pipelines (Fig. 4) is in operation in the United States to move anhydrous ammonia economically from points of production near natural gas sources to points of utilization in farming areas (see Pipelines). 

Other energy sector concerns are methane emissions from unburned fuel, and from natural gas leaks at various stages of natural gas production, transmission and distribution. The curtailment of venting and flaring stranded gas (remotely located natural gas sources that are not economical to produce liquefied natural gas or methanol), and more efficient use of natural gas have significantly reduced atmospheric release. But growth in natural gas production and consumption may reverse this trend. Methane has... 

JUNCTION-1,..., JUNCTION-15, PIPE-1,. PIPE-42, HYDROCARBON-SOURCE, SINK-1, SINK-2, HYDROGEN-SOURCE, NATURAL-GAS-SOURCE. CARBON-TETRACHLORIDE-SOURCE,... 

Nowadays, helium is no longer extracted from minerals, but from natural gas sources. 

For WTW analysis, it is a sufficiently accurate assumption, that natural gas mainly consists of methane (CFI4). Compressed natural gas is also referred to as CNG . Natural gas is extracted, processed, transported and distributed via pipeline to the filling stations, where it is compressed to about 25 MPa. Natural gas sources may vary for different countries. Depending on the source (natural gas quality) and the transport distance (e.g., 4000 km or even 7000 km from Russia, depending on the relevant gas fields) the auxiliary energy needs or energy losses, and hence the GHG-relevant emissions can vary. For the calculation of the energy requirement and GHG emissions for the supply of natural gas, a transport distance of 4000 km is assumed. 

Potential resource bases and the economic benefits of using the resource are being determined for unconventional natural gas sources. Numerous assessments have been performed by DOE, the gas industry, and other groups. The ranges of resource estimates from these assessments are summarized below. 

The natural gas sources are spread unevenly over the world with almost 70% of the natural gas reserves located in the Middle East, Russia and the Caucasus region as shown on Figure 4. Provided the consumption of primary energy sources is maintained at present level the depletion time is reportedly 60.7 years for natural gas according to BP [3] (40.6 years for oil, and 204 years for coal)1. Although these estimates do not reflect the real source, they confirm that the fossil resources are rather limited and may be depleted within a few generations. 

Figure 7 Concept map showing the applicability of energy transport technologies with practical and economical limitations originating from the utilisation of natural gas sources. The distance given is indicative, and may to some extent vary depending on local conditions.

Estimates place the world reserves of natural gas hydrates as being in the region of 5 X 1013 m3 on land, mostly in the permafrost regions of Alaska and Siberia, as well as a further 5-25 X 1015 m3 of gas in the oceans, particularly around Central America. This figure is around twice that of the total fossil fuel reserve this is an enormous wealth of energy which will become increasingly important as fossil fuels run out. Indeed, in the Russian Federation the enormous gas hydrate deposit at Messoyakha has been used as a natural gas source since 1971. 

Propane is released in the environment from automobile exhausts, burning furnaces, natural gas sources, and combustion of polyethylene and phenolic resins. 

An intimate relationship exists between the petroleum and chemical industries since about 85% of the primary organic chemicals produced today are derived from petroleum and natural gas sources. A comparison of petroleum utilization for energy and chemical industries illustrates that the major portion of every barrel of oil (90-92%) is used for energy production via total combustion to CO2 and water. In contrast to this, oxidation reactions in the chemical sector are made much more selective in nature by means of a catalyst that lowers the activation energy for the selected process and provides a facile path by which useful products can form. 

Another Ni-based solid oxide fuel cell (SOFC) electrode was developed on which a YSZ (yttria-stabilized zirconia) cermet and Lanthanum chromite were deposited by a slurry coating method. It was also suggested that a plasma spraying process can be used for the cermet deposition on the electrodes. The following reactions are expected to take place in a fuel cell employing a natural gas source, where internal reforming takes place on the Ni-YSZ electrode ... 

Figure 5.14 Hydrate-forming conditions for natural gas. Source [80],...

Figure 3.9 shows the proposed flowscheme. The natural gas, sourced from the pipeline, is desulfurized, preheated and led into a reactor where it is reformed to synthesis gas. The temperature controlled reactor continuously combines reaction and heat exchange, to maximize the utilization of the energy contained in the waste stream (discussed later). The synthesis gas is compressed and led into the methanol reactor. The methanol reactor is preferably of the temperature controlled type, again to maximize the heat transfer and maximize the intensity of the catalytic operation. The partially converted stream is subsequently flashed to remove methanol and water. Rather than recycling and recompressing the stream, it is expanded in a gas turbine, producing power. 

Fossil fuel-derived energy is receiving major attention as the most viable option for satisfying our near- to midterm energy needs. This possibility has also raised major concerns over the potential environmental and public health impacts associated with various fossil energy technologies. In particular, the anticipated shift away from petroleum and natural gas sources to coal- and oil-shale-derived fuels presents risks that cannot be estimated based upon current knowledge. 

In south central Asia, primarily India, several new nitrogen plants are in the planning stage, but the lack of in-country natural gas reserves requires the use of oil or naphtha as a feedstock. Feasibility studies on pipelines from the Middle East to India are in progress, but when this will result in natural gas sources for Indian nitrogen plants is conjectural. LNG as a feedstock is another consideration for India, but this is an expensive alternative. 

Helium is extracted from some natural gas sources that contain up to 10% helium by volume. It has many uses that depend upon its unique properties. Because of its very low density compared with air, helium is used to fiU weather balloons and airships. Helium is nontoxic, odorless, tasteless, and colorless. Because of these properties and its low solubility in blood, helium is mixed with oxygen for breathing by deep sea divers and persons with some respiratory ailments. Use of helium by divers avoids the very painful condition called the bends caused by bubbles of nitrogen forming from nitrogen gas dissolved in blood. 

Other attempts have aimed at creating a carbon-carbon bond fi om methane, although most natural gas sources contain a fraction of ethane and other lower alkanes. 

---