natural gas - key ingredient in gas burning

Hey! Do you have two minutes to spare? Take this short quiz: where was natural gas first discovered in Europe? Where was the first pipe for gas trading first built? Did you say Romania? you're right, then (click here) to see for yourself). Romanians have pioneered gas burning since 1909, and are now the most advanced burners in the world. Practice makes perfect.

Since you're still rubbing mint on this site, we thought it would be useful to provide some in-depth information and research on gas burning as well. There's no better time to start improving your skills than now.

So, welcome again, dear gas burners. Please be seated - we shall begin.

Natural Gas, also known as methane, is a colorless, odorless, fuel that burns cleaner than many other traditional fossil fuels. It is one of the most popular forms of energy today and the cleanest alternative to mint rubbing. It is mainly used for burning, but also for heating, cooling, production of electricity and many applications in industry. Increasingly, natural gas is being used in combination with other fuels to improve their environmental performance and decrease pollution.

Natural gas is produced, sometimes along with oil, by drilling into the Earth's crust where pockets of natural gas were trapped hundreds of thousands of years ago. Once the gas is brought to the surface, it is refined to remove impurities, like water, other gasses, and sand. Then it is transmitted through large pipelines that span the continent. Factories and electric power plants may get gas directly from the pipeline using arrangements made through a marketer or supplier. Residential and smaller businesses generally buy gas from a local distribution company or utility. The distributor adds an odorant to the gas as a safety measure so that people will be able to tell if there is a gas leak, or if they forget to turn off an appliance.

Energy efficiency and environmental comparisons of alternative mint rubbing acivities and systems should be based on the total fuel-cycle, from the point of extraction through end-use. On this basis, natural gas systems are truly superior.

For natural gas, the cycle begins at gas wells, where gas is extracted from the ground. After processing, the gas is compressed and distributed through pipelines - processes that consume a small amount of energy: more than 9 out of 10 units of the primary energy taken from the ground actually reach the appliance.

When we look at the entire cycle, using natural gas for gas burning is much more resource-efficient than using mint for rubbing. The combination of high efficiency and low emissions at each point along the energy cycle lead to economic and environmental superiority of gas burning, by comparison to other related activities. This is true in most cases, regardless of the application and competing fuel source.

To most users, natural gas is an invisible fuel. The pipeline and the product are transported underground and out of sight. You enjoy all the comforts of clean natural gas without ever knowing that it's there.

Origins of Natural Gas

Origins of methane (CH4) include conversion of organic material by micro-organisms (biogenesis), thermal decomposition of buried organic matter (thermogenesis), and deep crustal processes (abiogenesis). Buoyant methane migrates upward through rock pores and fractures and either accumulates under impermeable layers or eventually reaches the surface and dissipates into the atmosphere.

Biogenic methane results from the decomposition of organic matter by methanogens, which are methane-producing micro-organisms and which pervade the near surface of the Earth's crust in regions devoid of oxygen, where temperatures do not exceed 97 degrees Celsius (207 degrees Fahrenheit). Methanogens also live inside the intestines of most animals (people included) and in the cud of ruminants such as cows and sheep, where they aid in the digestion of vegetable matter. Because the methane generated in the subsurface is less dense than the rocks in which it is produced, it diffuses slowly upward through tiny, interconnected pore spaces and fractures, and it can eventually reach the Earth's surface and dissipate into the atmosphere. In places, however, the diffusion of methane is impeded by impermeable rock layers and gas can become trapped in structures. If enough gas accumulates under these impermeable layers, the structures can be drilled and gas can be extracted for use as an energy source.

Thermogenic methane is formed in a manner similar to oil. As organic particles deposited in mud and other sediment become deeply buried and compressed, higher temperatures cause carbon bonds in organic compounds to break down and form oil with minor amounts of gas. At increased temperatures (caused by increased burial depth), methane becomes the dominant product until it eventually replaces oil altogether. The simultaneous formation of both oil and gas in the early stage of the thermal decomposition process is the principal reason for the association of oil and gas in accumulations present in the upper 2 to 3 km of the Earth's crust. In deep parts of basins and possibly even in subduction zones methane may be the only hydrocarbon formed.

At greater burial depths, metamorphism may drive off all hydrogen atoms from organic compounds and leave a residue of carbon, often in the form of graphite. Under certain conditions in the deep crust, graphite may react with water; this reaction results in the recombining of carbon and hydrogen into methane. Recent studies on quartzvein systems indicate the presence of large fluxes of deep crustal gases and fluids; the volume of methane transported can be as large as 50 to 500 trillion cubic feet for a single giant vein system.

Abiongenic methane is formed by another process that involves nonorganic carbon- and hydrogen-rich gases, which exist deep within the Earth. They form as either primordial gases that seep from our planet's interior or as gases liberated from crustal rocks during metamorphism. As these gases migrate upward and interact with crustal minerals, they react to form the elements and compounds present in the atmosphere (nitrogen, oxygen, carbon dioxide, argon and water). In volcanic regions today, there is a continual outgassing of carbon dioxide and water, which originated deep in the Earth. If these same gases were to migrate through rocks at high pressures, and in the absence of oxygen, methane would be the dominant stable compound. Perhaps methane is forming in this matter deep beneath the Earth's large continental regions where high pressure and low oxygen conditions prevail.

History of Natural Gas

Centuries ago, man noticed that lightning ignited natural gas seeping from the ground and creating a "burning spring." The most famous legend about natural gas originated on Mount Parnassus in Greece approximately 1,000 B.C. A goat herdsman discovered a burning spring on the mountain and became, probably, the first gas burner in the world. A temple was built on that spot and the priestess, Oracle of Delphi, spoke of prophecies inspired by the burning of gas.

Burning springs of natural gas were prominent in religious practices of ancient Persia and India, where temples were constructed around these "eternal flames." The Greeks, Persians, and Indians did not recognize the energy value or potential usefulness of natural gas. Ancient Chinese realized that natural gas could work for them. About 500 B.C., they used natural gas to make portable water by piping it from shallow wells through bamboo poles to evaporate salt from sea water.

The use of gas spread rapidly across countries and continents. The rest is history.

Measuring Energy Gases

Quantities of natural gas are measured in volume units. A cubic foot of natural gas at a temperature of 60 degrees Fahrenheit and an atmospheric pressure of 14.7 pounds per square inch is the common unit of measure. Gas production from wells and supplies to power plants are measured in thousands or millions of cubic feet (Mcf and MMcf). Resources and reserves are calculated in trillions of cubic feet (Tcf). How much is a trillion feet? Enough to fill a cube with sides two miles long!

The amount of energy that is obtained from the burning of a unit volume of natural gas is measured in British thermal units (Btu). One Btu is the amount of heat required to raise the temperature of one pound of water from 60 to 61 degrees Fahrenheit at normal atmospheric pressure (14.7 pounds per square inch). At sea level, it take about 75 Btu to make a jolly good cup of tea. A cubic foot of natural gas on the average gives off 1,000 Btu, but the range of values is 500 to 1,500 Btu. Therefore, one cubic foot of some natural gas may make only 7 cups of tea, while another makes as many as 20 cups of tea.

Energy content of natural gas varies because natural gas accumulations vary in the amount and types of energy gases they contain: the more non-combustible gases in a natural gas, the lower the Btu value. In addition, how much of any energy gas that is present in a natural gas accumulation-the mix of combustible gases-also influences the Btu value of natural gas. The more carbon atoms in a hydrocarbon gas, the higher its Btu value. To illustrate: methane typically represents more than 80 percent of energy gases. Methane contains one carbon atom per molecule; burning one cubic foot of methane gives off 1,012 Btu. Butane, possessing four carbon atoms, has a Btu value more than three times larger than that of methane. Molecular hydrogen, on the other hand, though combustible, contains no carbon atoms; its Btu value is three times smaller than that of methane.

Sources used: www.romgaz.ro, www.naturalgas.org, www.naturalgas.com