常見可燃?xì)怏w含量不同單位下?lián)Q算

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,不同單位含義及換算示例,,,,,,,,,

,單位,,含義,,,,舉例,,,

,LEL,LEL,可燃蒸氣、氣體或粉塵與空氣組成的混合物遇火源即能發(fā)生爆炸的最低濃度（可燃蒸氣、氣體的濃度，按體積比計算）,,,,25LEL%是指為爆炸下限的25%,,,

,VOL,VOL,:氣體體積百分比，是物理單位,,,,5%VOL是指特定氣體在空氣中的體積占5%,,,

,ppm,ppm,氣體體積百分比含量的百萬分之一，無量綱常量,,,,5ppmCO是指空氣中含有百萬分之五的CO,,,

,mg/m3,mg/m3,一般作為空氣污染物濃度的表示方法，表示每立方米空氣中所含污染物的質(zhì)量數(shù),,,,表示每立方米空氣中所含污染物的質(zhì)量數(shù)，5000mg/m3表示每立方米空氣中所含NO的質(zhì)量為5000mg即5g,,,

,LEL換算成ppm,LEL換算成ppm,ppm=%LEL*LEL（VOL%）*100,,,,35%LEL的甲烷，它的LEL為2VOL%，按ppm顯示為35（%LEL）*2（VOL%）*100=7000ppm,,,

,LEL換算成VOL,LEL換算成VOL,VOL%=%LEL*LEL（VOL%）/100,,,,"如甲烷的爆炸下限是5%VOL，所以10LEL的甲烷氣體有以下對應(yīng)關(guān)系

10%LEL=5000ppm=0.5%VOL",,,

,ppm換算成mg/m3,ppm換算成mg/m3,"mg/m3=M/22.4·ppm·[273/(273+T)]*（Ba/101325）

M-氣體分子量，

ppm-測定的體積濃度值

T-溫度

Ba-壓力",,,,"如5000ppm的甲烷，因甲烷分子量約為26，

則26/22.4*5000=5822mg/m3",,,

,四者關(guān)系,,一般來說VOL是數(shù)量級最大的；LEL用于測爆的場合；ppm用于較為精準(zhǔn)的測量，ppm和VOL數(shù)值相差10000倍。mg/m3多用來表示空氣污染物濃度,,,,,,,

,不同可燃?xì)怏w單位換算關(guān)系,,,,,,,,,

,氣體,化學(xué)式,"爆炸下限

(體積分?jǐn)?shù))","爆炸上限

（體積分?jǐn)?shù)）",分子量,"氣體濃度

LEL",按VOL,按ppm,"按mg/m3

（0℃常壓）","按g/m3

（0℃常壓）"

,甲烷,CH4,5.0%,15.0%,26.083,10.0%,0.5%,5000,5822.1,5.822

,乙烷,C2H4,3.0%,15.5%,30.070,10.0%,0.3%,3000,4027.2,4.027

,丙烷,C3H8,2.2%,9.5%,44.096,1.0%,0.0%,220,433.1,0.433

,丁烷,C4H10,1.9%,8.5%,58.120,10.0%,0.2%,1900,4929.8,4.930

,氫,H2,4.0%,75.0%,2.016,10.0%,0.4%,4000,360.0,0.360

,異丁烷,C4H10,1.9%,8.4%,58.120,10.0%,0.2%,1900,4929.8,4.930

,一氧化碳,C0,12.5%,74.0%,28.010,10.0%,1.3%,12500,15630.6,15.631

,硫化氫,H2S,4.3%,45.0%,34.082,10.0%,0.4%,4300,6542.5,6.543

,乙醇,C2H5OH,3.4%,19.0%,46.070,10.0%,0.3%,3400,6992.8,6.993

,乙烯,C2H4,2.8%,32.0%,28.060,10.0%,0.3%,2800,3507.5,3.508

,乙炔,C2H2,1.5%,100.0%,26.040,10.0%,0.2%,1500,1743.8,1.744

,乙醛,CH3OH,4.0%,57.0%,44.053,10.0%,0.4%,4000,7866.6,7.867

,甲醇,CH3OH,5.5%,44.0%,32.040,10.0%,0.6%,5500,7867.0,7.867

,丙醇,C3H8,2.2%,13.5%,60.100,10.0%,0.2%,2200,5902.7,5.903

,丙烯,C3H6,2.4%,10.3%,42.080,5.0%,0.1%,1200,2254.3,2.254

,氨,NH3,15.0%,30.2%,17.031,10.0%,1.5%,15000,11404.7,11.405

,苯,C6H6,1.2%,8.0%,78.110,5.0%,0.1%,600,2092.2,2.092

,苯乙烯,C8H8,1.1%,8.0%,104.150,5.0%,0.1%,550,2557.3,2.557

,氯乙烯,C3H3CL,3.8%,31.0%,62.498,5.0%,0.2%,1900,5301.2,5.301

,一氯甲烷,CH3CL,8.1%,17.4%,50.490,10.0%,0.8%,8100,18257.5,18.258

,二氯甲烷,CH2CL2,15.5%,66.4%,8