10 Combustion

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, 2

, .

& , ,

H (CO2, H2O CO SO2) . CO2 CO O2 ( Orsat) N2 SO2 H 2O

30% CO2 5% CO 8% O2 32% N2 2% SO2 23% H2O (1 0.23)

39.0% CO2 6.5% CO 10.4% O2 41.5% N2 2.6% SO2

( ) (W) .

(2) 2 ( = 21%2, 79% 2) . . CO2 CO ( ). (CO) ( CO2)

3 110, 6 179

20 kg C2H4 400 kg 44 kg C2 12 kg CO. % ; : C2H4 + 3 O2 2 CO2 + 2 H2O mol: 20 kg C2H4 = 0.714 kmol C2H4 400 kg = 400/29 kmol 0.21400/29 kmol 2= 2.9 kmol 2 ( ;). O2=30.714= 2.14 kmol O2 = = (2.9-2.14)/2.14=35.5%

1

R 147

50% . 90%. 25% CO CO2. ( 21% O2 79% 2).

100 mol C2H6 nair=? yair,O2=0.21 yair,N2=0.79 50% C2H6+7/2 O2 2CO2 + 3 H2O C2H6+5/2 O2 2CO + 3 H2O nC2H6=? nO2=? nCO2=? nCO=? nN2=? nH2O=?

100 mol 2 < 100% C2H6 N2

( ) : 7 (nair, nC2H6, nCO2, nCO, nN2, nO2, nH2O) - : 3 (C, H, O) - : 1 (N2) - : 3 ( , , CO:CO2) => = 0

50% O2: 100 mol C2H6 3.5 mol O2/molC2H6 1.5 = 525 mol O2 nair = 525 mol O2 /0.21 = 2500 mol air 90% C2H6 nC2H6 = 100 0.9100 = 10 mol C2H6 To 25% C2H6 CO 0.25 90 mol C2H6 2 mol CO/mol C2H6 => nCO=45 mol CO

(2) = N2 0.79 2500 = nN2 = 1975 mol H 6 100 = 6 10 + 2 nH2O => nH2O= 270 mol H2O C 2 100 = 2 10 + nCO2 + 45=> nC2= 135 mol CO2 O 2 525 = 270 + 2 135 + 45 + 2 nO2 => nO2= 232.5 mol O2

(3) nC2H6+ nCO2 + nCO+ nN2+ nO2+ nH2O = 2667.5 mol

C 2 H6 0.37%

CO2 5.06%

CO 1.69%

N2 74.06%

O2 8.72%

H2 O 10.12%

nC2H6+ nCO2 + nCO+ nN2+ nO2 = 2397.5 mol

C 2 H6 0.42%

CO2 5.63%

CO 1.9%

N2 82.4%

O2 9.65%

2

R 149

. ( mol) 1.5% CO, 6% CO2, 8.2% O2 84.3% 2 ( ). C/H . ; .

nC=? nH=? nair=? yair,O2=0.21 yair,N2=0.79 P=100 mol nCO=1.5 mol CO nCO2=6 mol CO2 nO2=8.2 mol O2 nN2=84.3 mol N2

nH2O=?

100 mol N2

( ) : 4 (nair, nC, n, nH2O) - : 3 (C, H, O) - : 1 (N2) => = 0

: = 2 ( ) 0.79 nair = 84.3 => nair = 106.7 mol C nC = 1.5 + 6 = 7.5 mol O 2(0.21 106.7) = 1.5 + 2 6 + 2 8.2 + nH2O => nH2O =14.9 mol H nH = 2 14.9 mol = 29.8 mol

(2) C/ = 7.5/29.8 1/4 CH4 CH4 + 2 O2 CO2 + 2 H2O 7.5 mol C 7.5 mol CH4 15 mol O2 15 mol O2 15 /0.21 = 71.43 mol .. 106.7 mol .. = (106.7 71.43)/71.43 = 49.4%

3C 83.05% H 4.45% O 3.36% N 1.08% S 0.70% A 7.36%

6 187

.. : 100%

3.90%. 0.0048 gH2O/g . 14% . 2, CO2, SO2 2 2. 100 kg 50 kg.

C: 83.05 kg H: 4.45 kg O: 3.36 kg N: 1.08 kg S: 0.70 kg A: 7.36 kg H2O: 3.90 kg

: 100 kg

P=? C2=? S2=? O2 = ? N2 = ? 2=50 kg

A=? yA,O2: 0.21 yA,N2: 0.79 H2O: 0.0048 g/g ..

R=? : 14 % : 86 %

= 6 - = 4 - = 2 0

: : 3.9 kg H2O (1 kmol/18 kg) (2 kmol H/kmol)= 0.433 kmol H => 0.217 kmol O : 0.0048 g 2/g .. (29 g .. /mol) (1 mol /18 g 2) = 0.0077 mol H2O/mol . => 0.0154 mol H/mol .. & 0.0077 mol O /mol .. 7.36 = 0.86 R => R = 8.56 kg

C . . C 83.05/(100-7.36)=89.65%

89.65% 4.80% 3.63% 1.17% 0.76%

H O N S

O 14% 0.14 8.56=1.2 kg kmol C H O N S 0.8965 1.2 kg / 12 = 0.0897 kmol 0.0480 1.2 kg / 1 = 0.0537 kmol 0.0363 1.2 kg / 16 = 0.0027 kmol 0.0117 1.2 kg / 14 = 0.0010 kmol 0.0076 1.2 kg / 32 = 0.0003 kmol

= H 4.45/1 + 0.433 +0.0154 = 0.0537 + 250/18 => A= 47.15 kmol

N 2 0.79 A + 1.08/14 = 0.0010 + 2 nP,N2 => nP,N2 =37.28 kmol N2

C 83.05/12 = 0.0897 + nP,CO2 => nP,CO2 = 6.83 kmol CO2

S 0.7/32 = 0.0003 + nP,SO2 => nP,SO2 = 0.022 kmol SO2

I 3.36 + 0.217 + 0.0077 + 2 0.21 = 0.0027 + 2 6.83 + 2 0.022 + 2 nP,O2

nP,O2== 5.02 kmol O2

O2 : C + 2 C2 83.05/12 = 6.921kmol O2 2H2 + O2 2H2O 4.45/2 kmol H2(1kmol O2 /2 kmol H2) = 1.104 kmol O2 S + 2 S2 0.7/32 = 0.022 kmol O2 8.047 kmol O2 3.36/16 = 0.21 kmol O 0.105 kmol O2 A 8.047-0.105 = 7.942 kmol O2 O2 : 0.21 47.15 = 9.902 kmol O2 = 100 (9.902 7.942)/7.942 = 24.6%