Analysis Of Ingredients And Emissions Of Forest Fuel Combustion

14 kinds of arbor, 16 kinds of shrub and 15 kinds of herbage in different burning stagewere analyzed and computed emission factors and emission quantity of CO₂, CO, CxHy, NOand SO₂, burning characteristics of different forest fuels was analyzed from the perspective ofrelease speed in Daxing'anling by the method of wild investigation and laboratory controlcondition burning experiments.(1) CO₂, CO, CxHy, NO and SO₂ emission capacity were measured of each main speciesof arbor, shrub and herbage. The difference of gas emission between different types of forestfuel was tested by the method of Lowest Significance Difference (LSD). The result shows thatCO₂ is the dominating gas released during the fuel burning process, the difference of gasemission between different types of forest fuel is prominent (α=0.05).(2) From the analysis of different kinds of gas emission characteristic, CO emissionobviously increases while burning insufficiently; CO emission curve is bimodal in shape, thepeak value of the frst peak is obviously greater than the second peak, emission time is longerthan other gases notably; CO also takes the shortest time to reach the release peak and CO₂takes the longest time to reach the peak. CO bimodal emission curve is a very favorableidentification of preheating, decomposing, flaming and smoldering during burning.(3) CO₂ emission factor is greater than other gases obviously within five kinds of gas.CO₂, CO, CxHy, NO and SO₂ emission factors of arbor, shrub and herbage are 2.4997, 0.6738,0.0315, 0.0097, 0.0167; 2.7807, 0.5217, 0.0241, 0.0124, 0.0170; 2.7698, 0.5364, 0.0196,0.0104, 0.0191, respectively.(4) The difference is obvious of five kinds of gas between arbor, shrub and herbage, butthe prominent intensity of difference is inconsistent by the method of LSD (α=0.05). Thesequence of CO₂ emission average is herbage＞shrub＞arbor, the difference is not prominentbetween herbage and shrub; the sequence of CO emission average is herbage＞arbor＞shrub, thedifference is not prominent between arbor and shrub; the sequence of CxHy emission averageis arbor＞shrub＞herbage, the difference is not prominent between arbor and shrub; the sequenceof NO emission average is shrub＞herbage＞arbor, the difference is not prominent betweenshrub and herbage; the sequence of SO₂ emission average is herbage＞shrub＞arbor, thedifference is prominent between arbor, shrub and herbage. CO₂ emission of herbage is largerthan arbor and shrub, the duration of sufficient combustion process is long, flaming stageproportion is larger, and the burning characteristics is obvious.(5) CO₂, CO, CxHy, NO and SO₂ emission quantity of 5g sample of arbor, shrub andherbage are 5624.28mg, 1516.10mg, 70.95mg, 21.88mg, 37.61mg; 6255.49mg, 1174.49mg, 54.13mg, 27.85mg, 38.33mg; 6232.03mg, 1206.97mg, 44.10mg, 23.49mg, 43.02mg,respectively. By the method of LSD (α=0.05), the sequence of CO₂ emission quantity isshrub＞herbage＞arbor, the difference is not prominent between shrub and herbage; the sequenceof CO emission quantity is arbor＞shrub＞herbage, the difference is not prominent betweenshrub and herbage; the sequence of CxHy emission quantity is arbor＞shrub＞herbage, thedifference is prominent between arbor, shrub and herbage; the sequence of NO emissionquantity is shrub＞herbage＞arbor, the difference is not prominent between arbor and herbage;the sequence of SO₂ emission quantity is herbage＞shrub＞arbor, the difference is not prominentbetween arbor and shrub.