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Carbon monoxide, flame combustion

Bone and co-workers [4] studied the formation of nitric oxide in the combustion of carbon monoxide and arrived at some very strange results, e.g., yields of nitric oxide exceeding equilibrium values, a sharply negative influence of water vapor and hydrogen, etc. Bone concluded that the reaction of nitrogen with oxygen is caused by activation of the nitrogen by radiation from the carbon monoxide flame. [Pg.364]

Kilham, J. K., and Dunham, R G. "Energy Transfer from Carbon Monoxide Flames." 11th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA, 899-905, 1967. [Pg.138]

The flames of H2, CO, and hydrocarbons with oxygen form a heirarchy. The hydrogen flame has the simplest chemistry. The carbon monoxide flame is next in complexity and includes all of the reactions of the hydrogen system because some trace of water or hydrogen is required to support combustion. The hydrocarbon flames follow in complexity. In addition to their own chemistry, they also involve both the CO and hydrogen systems. In lean flames the chemistry involves that of the fuel and all of its lower homologs. Rich hydrocarbon flame chemistry is much more complex. [Pg.88]

Measurements of the reaction rate in rarefied carbon monoxide flames show a direct proportionality between the conversion of CO to CO2 (at low extents of conversion ruling out substantial heating of the gas) and the moisture content of the mixture [229] as well as the virtually complete termination of the reaction upon removal of moisture from the combustion zone in the course of the reaction. This is evidence that water vapour acts as a homogeneous catalyst in CO combustion. [Pg.215]

Thermochonistry — The Thomsen-Berthelot Principle — Free Energy — Dissociation — Equilibrium and Heat of Reaction — The Nemst Heat Theorem — Dixon — Influence of Moisture on Chemical Changes — The Burning of Carbon Monoxide — The Combustion of Hydrocarbons — Luminosity of Flames — The Detonation Wave — Nemst—Haber. [Pg.517]

The combustible components of the gas are carbon monoxide and hydrogen, but combustion (heat) value varies because of dilution with carbon dioxide and with nitrogen. The gas has a low flame temperature unless the combustion air is strongly preheated. Its use has been limited essentially to steel (qv) mills, where it is produced as a by-product of blast furnaces. A common choice of equipment for the smaller gas producers is the WeUman-Galusha unit because of its long history of successful operation (21). [Pg.63]

Occurrence. Carbon monoxide is a product of incomplete combustion and is not likely to result where a flame bums in an abundant air supply, yet may result when a flame touches a cooler surface than the ignition temperature of the gas. Gas or coal heaters in the home and gas space heaters in industry have been frequent sources of carbon monoxide poisoning when not provided with effective vents. Gas heaters, though properly adjusted when installed, may become hazardous sources of carbon monoxide if maintained improperly. Automobile exhaust gas is perhaps the most familiar source of carbon monoxide exposure. The manufacture and use of synthesis gas, calcium carbide manufacture, distillation of coal or wood, combustion operations, heat treatment of metals, fire fighting, mining, and cigarette smoking represent additional sources of carbon monoxide exposure (105—107). [Pg.59]

Nitrogen Oxides. From the combustion of fuels containing only C, H, and O, the usual ak pollutants or emissions of interest are carbon monoxide, unbumed hydrocarbons, and oxides of nitrogen (NO ). The interaction of the last two in the atmosphere produces photochemical smog. NO, the sum of NO and NO2, is formed almost entkely as NO in the products of flames typically 5 or 10% of it is subsequently converted to NO2 at low temperatures. Occasionally, conditions in a combustion system may lead to a much larger fraction of NO2 and the undeskable visibiUty thereof, ie, a very large exhaust plume. [Pg.529]

Pollutant Formation and Control in Flames Key combustion-generated air pollutants include nitrogen oxides (NOJ, sulfur oxides (principally SO9), particulate matter, carbon monoxide, and unburned hydrocarbons. [Pg.2380]

Carhon Monoxide Carbon monoxide is a key intermediate in the oxidation of all hydrocarbons. In a well-adjusted combustion system, essentially all the CO is oxidized to CO9 and final emission of CO is veiy low indeed (a few parts per million). However, in systems which have low temperature zones (for example, where a flame impinges on a wall or a furnace load) or which are in poor adjustment (for example, an individual burner fuel-air ratio out of balance in a multiburner... [Pg.2382]

Carbon monoxide is usually sampled as the second parameter in conjunction with carbon dioxide or oxygen. In theory, as the optimum is usually to have near-stoichiometric combustion without CO breakthrough it is the most reliable gas to sample. A problem is that although small quantities of CO usually indicate the need for additional air, they can also be caused by flame chilling and careful interpretation of results is needed. [Pg.276]

Carbon monoxide (CO) is a colorless and odorless gas molecule. This inorganic compound, at standard temperature and pressure, is chemically stable with low solubility in water but high solubility in alcohol and benzene. Incomplete oxidation of carbon in combustion is the major source of environmental production of CO. When it burns, CO yields a violet flame. The specific gravity of CO is 0.96716 with a boiling point of -190°C and a solidification point of-207°C. The specific volume of CO is 13.8 cu ft/lb (70°F). [Pg.321]

The flaming results extend to = 4 in Figures 2.3 and 2.4, at which point gas phase combustion appears to cease. However, combustion must continue since the heat of combustion remains nonzero. This is due to oxidation of the remaining solid fuel. If we consider wood, it would be the oxidation of the surface char composed primarily of carbon. From Example 2.3, we obtain the heat of combustion for carbon (going to CO2) as 32.8 kJ/g carbon. From Figure 2.4, we see a significant production of carbon monoxide at < > 4, and therefore it is understandable that Figure 2.3 yields a lower... [Pg.41]

Methane, also referred to as marsh gas, is a gas composed of carbon and hydrogen with a chemical formula of CH4. It is the first member of the paraffin or alkane series of hydrocarbons. It is lighter than air, colorless, odorless, tasteless and is flammable. It occurs in natural gas and as a by-product of petroleum refining. In atmospheric burning no smoke production normally occurs. In air methane bums with a pale, faintly luminous flame. With excess air carbon dioxide and water vapor is formed during combustion, with an air deficiency carbon monoxide and water is formed. It forms an explosive mixture with air over a moderate range. Its primary uses are as a fuel and raw feedstock for petrochemical products. [Pg.34]

A gaseous paraffinic hydrocarbon, CHj.CHj that is colorless and odorless and normally found in natural gas, usually in small proportions. It is slightly heavier than air and practically insoluble in water. When ignited in atmospheric burning it produces a pale faintly luminous flame with little or no smoke production. With excess air during combustion it produces carbon dioxide and water, with limited air supplies the combustion process will produce carbon monoxide and water. It forms an explosive mixture with air over a moderate range. [Pg.35]

Particularly important compounds have been studied by flame combustion calorimetry. Methane [92-94], ethanol [95], diethyl ether [96], carbon monoxide [92,93,97], hydrochloric acid [98], and water [93,97,99] are representative examples. With a few exceptions (HC1, H2O, D2O [100], SO2 [101], cyanogen [102,103], and some lower chloroalkanes [104,105]), measurements by flame combustion calorimetry have been limited to substances of general formula CaHbOc. [Pg.115]

FIGURE 9.18 Schematic of the double-film model of carbon particle combustion, whereby carbon monoxide produced at the particle surface is oxidized to carbon dioxide in a boundary layer flame, consuming the oxygen that is diffusing toward the particle. [Pg.533]

PCDD/F and other chlorinated hydrocarbons observed as micropollutants in incineration plants are products of incomplete combustion like other products such as carbon monoxide, polycyclic aromatic hydrocarbons (PAH), and soot. The thermodynamically stable oxidation products of any organic material formed by more than 99% are carbon dioxide, water, and HCl. Traces of PCDD/F are formed in the combustion of any organic material in the presence of small amounts of inorganic and organic chlorine present in the fuel municipal waste contains about 0.8% of chlorine. PCDD/F formation has been called the inherent property of fire. Many investigations have shown that PCDD/Fs are not formed in the hot zones of flames of incinerators at about 1000°C, but in the postcombustion zone in a temperature range between 300 and 400°C. Fly ash particles play an important role in that they act as catalysts for the heterogeneous formation of PCDD/Fs on the surface of this matrix. Two different theories have been deduced from laboratory experiments for the formation pathways of PCCD/F ... [Pg.180]

Cherian, M. A., P. Rhodes, R. J. Simpson, and G. Dixon-Lewis. 1981. Kinetic modelling of the oxidation of carbon monoxide in flames. 18th Symposium (International) on Combustion Proceedings. Pittsburgh, PA The Combustion Institute. 385-96. [Pg.422]


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