Hydrocarbon from biomass burning

Barrefors G, Petersson G. 1995. Assessment by gas chromatography and gas chromatography-mass spectrometry of volatile hydrocarbons from biomass burning. J Chromatogr 710 71-77. 

Greenberg, J. P., P. R. Zimmerman, L. Heidt, and W. Pollock (1984). Hydrocarbon and carbon monoxide emissions from biomass burning in Brazil. J. Geophys. Res. 89, 1350-1354. 

Emissions from biomass burning could disrupt the oxidizing potential of the atmosphere. The atmosphere has a self-cleaning mechanism, which photochemically oxidized pollutants, such as hydrocarbons, to carbon dioxide, preventing their buildup... 

The key molecule responsible for this oxidation process is OH. The reaction chains involved are such that OH is consumed when the concentration of NOx is low. This is the normal condition of most of the unpolluted troposphere. On the basis of the observed increase of CO and CH4, it has heen suggested that global decreases in OH, the primary sink for CH4 and CO, could lead through a feedback mechanism to a further increase in CO and CH4, and that this situation could produce an unstable chemical condition [56]. Injection of large amounts of NOx from biomass burning and other anthropogenic activities may counteract this feedback, because hydrocarbon oxidation in the presence of elevated amounts of NOx creates additional O3 and OH. This counter effect is, however, much more regionally limited because of the much shorter residence time of NOx compared to that of CO and CH4. 

The measurements refer to nine 600-liter canister samples, three collected south and six north of the ITCZ, analyzed according to the method of C.A.M. Brenninkmeijer [C.A.M. Brenninkmeijer, Journal of Geophysical Research, 98 10595 (1993) C.A.M. Brenninkmeijer et al., Chemosphere Global Change Science, 1 33 (1999)]. CO can result from biomass burning and die oxidation of natural hydrocarbons. Forest emissions of hydrocar-bons, however, are small, whereas hydrocarbon oxidation is minimal during winter. 

Polycyclic aromatic hydrocarbons (PAHs, sometimes also called polynuclear aromatics, PNA) are a hazardous class of widespread pollutants. The parent structures of the common PAHs are shown in Fig. 4 and the alkylated homologs are generally minor in combustion emissions. PAHs are produced by all natural combustion processes (e.g., wild fires) and from anthropogenic activity such as fossil fuels combustion, biomass burning, chemical manufacturing, petroleum refining, metallurgical processes, coal utilization, tar production, etc. [6,9,15,18, 20,24,131-139]. 

By comparison, the average CO mixing ratio in Earth s troposphere is —0.12 ppmv and it is produced from a variety of anthropogenic and biogenic sources such as fossil fuel combustion, biomass burning, and oxidation of methane and other hydrocarbons. Most of the CO in Earth s troposphere is destroyed by reaction with OH radicals, which are also important for the catalytic... 

O Malley V. P., Burke R. A., and Schlotzhauer W. S. (1997) Using GC-MS/Combustion/lRMS to determine the ratios of individual hydrocarbons produced from the combustion of biomass materials—application to biomass burning. Org. Geochem. 21, 567-581. 

The oxidizing power of the atmosphere has likely decreased significantly, especially in the Northern Hemisphere, as a result of human activities. As a result, the lifetime of methane may have increased by 10-15% since the preindustrial era. At the same time, the abundance of tropospheric ozone has increased perhaps by as much as a factor of 2-3 in the Northern Hemisphere. Enhanced biomass burning fluxes of NO CO, and hydrocarbons from tropical ecosystems are likely to be important. Future changes in tropospheric ozone are predicted to be largest in the tropics (India, China). These projected increases in tropical emissions are likely to have a... 

Use of Different Fuels and Their Characteristics - The best commercial, dry, low NOx combustors today are optimized for clean-burning natural gas. However, with raised natural gas prices over the next decade, power plants may be forced to burn low-heating value fuel gas, products of gasification or low quality residual fuels. As the combustion becomes more complicated, e.g. lean-premixed combustors, to handle NOx emissions from different fuels is bound to become more complex, too. Hence, development of the catalytic combustor must also be directed towards fuels other than natural gas. These fuels could be other hydrocarbon feedstock, e.g. diesel fuels,which are more available than natural gas in some parts of the world, and kerosene,which is used for jet-turbines in aeroplanes. An increased use of renewable fuels, such as methanol, ethanol and low-heating value fuels derived from biomass or waste will also lead to a demand to put these fuels to use in gas turbines. ... 

VOCs are mainly hydrocarbons (2.73 Mt in 1997 in the UK) and the most abundant is methane (50% from landfills, 30% from animals, and rest from gas extraction, biomass burning) while non-methane VOC in 1997 in the UK (2.13 Mt in the UK) are mainly emitted from vehicles (40%), from solvents in paints (30%), etc., which is composed of some 200 different hydrocarbons such as benzene and toluene [34],... 

Estimates for emissions from anthropogenic sources of hydrocarbons fall in the range 70-180 Tg yr . Three types of sources are most important The production of liquid fuels from petroleum and road traffic contributes about 54% in developed countries and 36% worldwide. Solvent use adds another 15%. The third major source is biomass burning, which contributes 34% on a global scale (16% in developed countries). About 45%of the emissions are alkanes, 35% are alkenes, and 17% are aromatic compounds. 

Incomplete combustion of oil and other carbonaceous materials, e.g., in internal combustion engines, industrial processes Bjprseth and Ekbmd, 1979), domestic heating, forest fires and intentional biomass burning Greenberg et al., 1984) is another source of polycyclic aromatic hydrocarbons (PAH), primarily to the atmosphere. Dry deposition and atmospheric precipitation are the principal vectors of their transport into surface seawater. Gustafsson et al. (1997) discussed the export of deposited PAH from surface waters by association with sinking particles. 

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