Fossil fuels: natural gas

Nonrenewable energy sources include the fossil fuels (natural gas,... 

Other important natural sources of organic chemicals are the so-called fossil fuels - natural gas, petroleum, and coal - all deposited in the earth from the decay of plant and animal remains, and containing thousands of degradation products. Most of these are simple compounds containing only carbon and hydrogen (technically and even reasonably known as hydrocarbons). Natural gas is relatively simple... 

For many applications, hydrogen is the most convenient fuel, but it is not a primary fuel, so that it has to be produced from different sources water, fossil fuels (natural gas, hydrocarbons, etc.), biomass resources and so on. Moreover, the clean production of hydrogen (including the limitation of carbon dioxide production) and the difficulties with its storage and large-scale distribution are still strong limitations for the development of such techniques [2, 3]. In this context, other fuels, particularly those, like alcohols, which are liquid at ambient temperature and pressure, are more convenient due to the ease of their handling and distribution. 

Small reformers R D areas include compact and low cost reformers (1-5 kW) to convert fossil fuels (natural gas, gasoline) or biomass fuels (ethanol) to hydrogen via different processes (steam reforming, partial oxidation, auto-thermal, non catalytic hybrid steam reforming). Improvements in reformer efficiency, capacities and response times, and integration of purification unit are also being studied. Examples of projects include ... 

The main advantage of natural gas is that it burns cleanly, producing only carbon dioxide and water. Of all the fossil fuels, natural gas is considered the cleanest form of energy. It emits less sulfur, carbon, and nitrogen when burned than coal or oil and it leaves almost no solid ash particles. 

Hetland J., Advantages of Natural Gas Over Other Fossil Fuels. Natural Gas Technologies, Opportunities and Development Aspects, OPET-Intemational Workshop Papers, Vaasa, Finland, May, 2002... 

Today Production of -65 M tonnes hydrogen [mainly from fossil fuels (natural gas, oil, coal...)] at a cost of EUR 1.8/kg [USD 2.3/kg] essentially for fertilisers and refinery of heavy crude oil. 

Compared with other fossil fuels, natural gas is a cost-effective feed for making hydrogen, in part because it is widely available, is easy to handle, and has a high hydrogen-to-carbon ratio, which minimises the formation of by-product C02. Hydrogen can currently be produced from natural gas by means of ... 

We see that the incomplete combustion of hydrocarbons yields undesirable products —carbon monoxide and elemental carbon (soot), which pollute the air. Unfortunately, all fossil fuels—natural gas, coal, gasoline, kerosene, oil, and so on—also have undesirable nonhydrocarbon impurities that burn to produce oxides that act as additional air pollutants. At this time it is not economically feasible to remove all of these impurities from the fuels before burning them. 

The pathways involving fossil fuels (natural gas, refinery oil and coal) that provide for almost 96% of the total production of hydrogen, release carbon dioxide in the atmosphere. 

Propane is most widely available as a component of petroleum and natural gas, fossil fuels that formed many millions of years ago when marine organisms died, sank to the bottom of seas, and were eventually buried under massive layers of debris. The decay of those organisms without access to oxygen resulted in the formation of so-called fossil fuels natural gas, petroleum, and coal. All fossil fuels are complex mixture of some free carbon and a very large variety of... 

Compared with other fossil fuels, natural gas is the most desirable feed for making hydrogen. It is widely available, easy to handle and relatively cheap (at present). Moreover, the gas has the highest hydrogen-to-carbon ratio of all fuels (see Figure 1.1, Chapter 1) and this serves to minimize the quantity of by-product carbon dioxide. 

For the next few decades, saving of uranium resources by nuclear fuel breeding will not be of primary importance for countries with a significant nuclear power sector. This is caused by a number of factors, namely (a) accumulation of plutonium as a result of reprocessing of spent fuel of the operating NPPs (b) release of considerable amount of plutonium and enriched uranium owing to disarmament (c) decrease of uranium consumption in the military industry (d) slowing down of the rate of nuclear power development and (e) ready availability of fossil fuels (natural gas and oil). 

Hydrogen can be obtained firom different sources as fossil fuels (natural gas reforming, and coal gasification), renewable fuels (biomass), algae, and vegetables or water (electrolysis and thermo-chemical cycles). Many different energy sources can be used in most of these processes heat from fossil fuel or nuclear reactors, electricity from several sources as solar energy. 

Hydrocarbons are the principal component of fossil fuels. Natural gas is primarily methane, crude petroleum is a complex mixture of thousands of hydrocarbons, and coal is an even more complex mixture of hydrocarbons. Many of the fuels we use, such as gasoline and jet fuel, are obtained from petroleum. 

Direct thermal splitting is one such way - and there is work going on looking at efficient catalysts for this [9,10]. Electrolysis is another and well-understood way -the use of electric power to split water. It may be driven by electricity from any source - conventional (fossil fuelled), wind power, hydro or wave power, nuclear or PV [11]. Steam methane reformation (SMR) is at present the cheapest way to produce hydrogen, and relies on fossil fuel (natural gas). This provides a cost per kg and kWh of Ha burnt split between capital and electrical power cost [12, 13]. 

Fossil fuels—natural gas, petroleum, and coal—are the principal sources of hydrocarbons. Natural gas is primarily methane with small amounts of ethane, propane, and butane. Petroleum is a mixture of hydrocarbons from which gasoline, kerosene, fuel oil, lubricating oil, paraffin wax, and petrolatum (themselves mixtures of hydrocarbons) are separated. Coal tar, a volatile by-product of the steel industry s process of making coke from coal, is the source of many valuable chemicals, including the aromatic hydrocarbons benzene, toluene, and naphthalene. 

The three major sources of alkanes throughout the world are the fossil fuels natural gas, petroleum, and coal. Fossil fuels account for approximately 90% of the total energy consumed in the United States. Nuclear electric power and hydroelectric power make up most of the remaining 10%. In addition, fossil fuels provide the bulk of the raw material for the organic chemicals consumed worldwide. 

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