94:95 ¼ p þ q
ð6:E6Þ
88:25 þ 2f ¼ 4p þ 3r þ 2s
ð6:E7Þ
86:30 þ f ¼ 2q
ð6:E8Þ
1:16 ¼ r
ð6:E9Þ
0:03 ¼ s
ð6:E10Þ
Solving above equations, the values of f, p, q, r, and s were found to be
f ¼ 30:62
p ¼ 36:49
q ¼ 58:46
r ¼ 1:16
s ¼ 0:03
Similarly, for wheat bran,
9:63 ¼ p þ q
ð6:E11Þ
9:94 þ 2f ¼ 4p þ 3r þ 2s
ð6:E12Þ
Table 6.3 Percentage of carbon, hydrogen, oxygen, nitrogen, and sulfur in carbohydrates, lipids,
and proteins
Elements
Carbohydrates
Lipids
Proteins
Carbon
42.7
84.6
52.7
Hydrogen
3.2
5.1
7.1
Oxygen
54.1
10.3
22.6
Nitrogen
–
–
16.5
Sulfur
–
–
1.1
Table 6.2 Biochemical composition of carbohydrates, lipids, and proteins in cassava wastewater,
wheat bran, and sewage sludge
Constituents
Carbohydrates (ppm)
Lipids (ppm)
Proteins (ppm)
Cassava wastewater
2507.36
19.74
98.72
Wheat bran
146.28
30.0
52.50
Sewage sludge
148.00
46.7
73.50
6 Stoichiometric Analysis of Biogas Production from Industrial Residues
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