Methane is a gaseous chemical compound with the chemical formula CH4.This is the simplest representative of alkanes.Another name for this group of organic compounds: limit saturated or paraffinic hydrocarbons.They are characterized by having a single bond between carbon atoms in the molecule, and all the remaining valences of the carbon atoms of each saturated with hydrogen atoms.For alkanes the most important reaction is the burning.They burn to form carbon dioxide gas and water vapor.As a result, it releases massive amounts of chemical energy, which is converted into heat or electricity.Methane is a flammable liquid and the main component of natural gas, which makes it an attractive fuel.At the widespread use of natural resources is the combustion reaction of methane.Since it is normally a gas, it is difficult to transport over long distances from the source, so it is often pre-liquefied.
combustion process is the reaction between methane and oxygen, i.e. in the simplest alkane oxidation.This produces carbon dioxide, water and a lot of energy.Burning methane can be described by the equation: CH4 [gas] + 2O2 [gas] → CO2 [gas] + 2H2O [pairs] + 891 kJ.That is, one molecule of methane by reaction with two molecules of oxygen forms carbon dioxide molecules and two water molecules.This releases heat energy equal to 891 kJ.Natural gas is the cleanest burning fossil for as coal, oil and other fuels more complex in composition.Therefore, when they are isolated in the combustion air various harmful chemicals.Since natural gas mainly composed of methane (about 95%), then burning it hardly produces by-products or their turns are much smaller than in the case of other fossil fuels.
Caloricity methane (55.7 kJ / g) is higher than its homologues, such as ethane (51.9 kJ / g), propane (50.35 kJ / g), butane (49.50 kJ /d) or other fuels (wood, coal, kerosene).Combustion of methane yields more energy.To provide for a year of incandescent bulbs with 100 watts need to burn 260 kg of wood, or 120 kg of coal, or 73.3 kg of kerosene, or only 58 kg of methane, which corresponds to 78.8 cubic meters of natural gas.
simplest alkane is an important resource for electricity generation.This occurs by burning it as fuel in a boiler to generate steam which drives a steam turbine.Also, the burning of methane used to produce hot combustion gases, the energy which provides the gas turbine (burning is carried out to the turbine or of the turbine).In many cities, methane is piped into the house for domestic heating and cooking.Compared with other types of hydrocarbon fuel burning natural gas has a lower emission of carbon dioxide and a large amount of generated heat.
Burning methane is used to achieve high temperatures in furnaces of various chemical industries, for example, large-capacity ethylene plant.The natural gas mixed with air supplied to the burners of the pyrolysis furnace.During combustion the flue gases are formed with a high temperature (700-900 ° C).They heat pipe (located within the furnace) in which the feed mixture is supplied with steam (in order to reduce coke formation in the furnace tubes).Under the action of high temperatures, the plurality of chemical reactions, which will yield the target components (ethylene and propylene) and byproducts (resin Heavy pyrolysis, hydrogen and methane fractions, ethane, propane, hydrocarbons, C4, C5, Pirocondensate; each of them has its applicationFor example, Pirocondensate used to produce benzene or motor gasoline components).
Burning methane is a complex physical and chemical phenomena on the basis of an exothermic redox reaction, characterized by high flow rate and the release of huge amounts of heat and heat transfer and mass transfer processes.Therefore, the calculated determination of the temperature of combustion mixture is a complex task, since in addition to air-fuel ratio greatly influence its pressure and the initial temperature.With their increase in the rise of temperature of combustion and heat transfer, and mass transfer processes contribute to its reduction.Methane combustion temperature in the design processes and apparatuses chemical production determined by calculation, and the existing installations (e.g., in the pyrolysis furnaces), it is measured using thermocouples.
