|
|
PROXIMATE AND ULTIMATE
ANALYSES
Biomass
fuels are characterized by what is
called the "Proximate and Ultimate analyses".
The "proximate" analysis gives moisture content,
volatile content (when heated to 950 C), the free carbon
remaining at that point, the ash (mineral) in the sample
and the high heating value (HHV) based on the complete
combustion of the sample to carbon dioxide and liquid water.
(The low heating value, LHV, gives the heat released when
the hydrogen is burned to gaseous water, corresponding to most
heating applications and can be calculated
from the HHV and H2 fraction.)
The "ultimate" analysis" gives the composition of
the biomass in wt% of carbon, hydrogen and oxygen (the major
components) as well as sulfur and nitrogen (if any).
The table
below, showing Proximate
and Ultimate analyses, is from Appendix A of our book1,
and gives analyses of over 140 fuels, including biomass
components, natural biomass (woods, agricultural products),
processed biomass, other solid and liquid fuels. For
ease of reading download to a spreadsheet file.
The Proximate Analysis (D-3175),
gives the fixed carbon, volatile and ash content of biomass.
The Ultimate Analysis gives the elemental (C, H, O, S, N)
analysis. The Gross heating value The data is
often published with various articles in widely scattered
journals. The data have been brought together for
convenience in this one place. These standard ASTM tests
and are performed by many laboratories in the country, routinely
on coal, but competently on biomass. They typically cost
$100-$200 so it is good to be able to find collected results for
various biomass materials.
Our book "Thermal Data for
Natural and Synthetic Fuels", Marcel Dekker, 1998, gives an
extended list of the Prox and Ult analyses of about 300 forms of
biomass, most of which were collected in the thesis of S. A.
Channiwala from the Indian Institute of Technology, 1992.
I have long been fascinated with
the close relationship between the heat of combustion (high
heating value, HHV) and the elemental composition as given in
the ultimate analysis. This was first noticed by DuLong in the
19th century and brought up to date by other scientists.
Most recently a Mr. S. A. Channiwala 1992 thesis, The Indian
Institute of Technology, Bombay) collected data on over 200
species of biomass and fitted the following equation to the
data:
HHV (in kJ/g) = 0.3491C + 1.1783 H - 0.1034 O - 0.0211 A +
0.1005 S -0.0151 N
(where C is the weight fraction
of carbon; H of hydrogen; O of oxygen; A of ash; S of sulfur and
N of nitrogen appearing in the sltimate analysis. )
He found that this equation
fitted the experimental data with an average error of 1.45%,
typical of the error of most measurements. This equation
permits using heat values in calculations and models of biomass
processes.
Other analyses can be found at
the following websites:
The Energy Center of
the Netherlands,
IEA,
The International Energy Agency,
Biobib
(Austria)
|
Name
|
Fixed
|
Volatiles
|
Ash
|
C
|
H
|
O
|
N
|
S
|
HHV
|
HHV
|
| |
Carbon
|
|
|
|
|
|
|
|
MEAS
|
CALC
|
| |
%
|
%
|
%
|
%
|
%
|
%
|
%
|
%
|
kJ/g
|
kJ/g
|
|
WOOD
|
|
|
|
|
|
|
|
|
|
|
|
Beech
|
-
|
-
|
0.65
|
51.64
|
6.26
|
41.45
|
0.00
|
0.00
|
20.38
|
21.10
|
|
Black
Locust
|
18.26
|
80.94
|
0.80
|
50.73
|
5.71
|
41.93
|
0.57
|
0.01
|
19.71
|
20.12
|
|
Douglas
Fir
|
17.70
|
81.50
|
0.80
|
52.30
|
6.30
|
40.50
|
0.10
|
0.00
|
21.05
|
21.48
|
|
Hickory
|
-
|
-
|
0.73
|
47.67
|
6.49
|
43.11
|
0.00
|
0.00
|
20.17
|
19.82
|
|
Maple
|
-
|
-
|
1.35
|
50.64
|
6.02
|
41.74
|
0.25
|
0.00
|
19.96
|
20.42
|
|
Ponderosa
Pine
|
17.17
|
82.54
|
0.29
|
49.25
|
5.99
|
44.36
|
0.06
|
0.03
|
20.02
|
19.66
|
|
Poplar
|
-
|
-
|
0.65
|
51.64
|
6.26
|
41.45
|
0.00
|
0.00
|
20.75
|
21.10
|
|
Red
Alder
|
12.50
|
87.10
|
0.40
|
49.55
|
6.06
|
43.78
|
0.13
|
0.07
|
19.30
|
19.91
|
|
Redwood
|
16.10
|
83.50
|
0.40
|
53.50
|
5.90
|
40.30
|
0.10
|
0.00
|
21.03
|
21.45
|
|
Western
Hemlock
|
15.20
|
84.80
|
2.20
|
50.40
|
5.80
|
41.10
|
0.10
|
0.10
|
20.05
|
20.14
|
|
Yellow
Pine
|
-
|
-
|
1.31
|
52.60
|
7.00
|
40.10
|
0.00
|
0.00
|
22.30
|
22.44
|
|
White
Fir
|
16.58
|
83.17
|
0.25
|
49.00
|
5.98
|
44.75
|
0.05
|
0.01
|
19.95
|
19.52
|
|
White
Oak
|
17.20
|
81.28
|
1.52
|
49.48
|
5.38
|
43.13
|
0.35
|
0.01
|
19.42
|
19.12
|
|
Madrone
|
12.00
|
87.80
|
0.20
|
48.94
|
6.03
|
44.75
|
0.05
|
0.02
|
19.51
|
19.56
|
|
Mango
Wood
|
11.36
|
85.64
|
2.98
|
46.24
|
6.08
|
44.42
|
0.28
|
|
19.17
|
18.65
|
|
BARK
|
|
|
|
|
|
|
|
|
|
|
|
Douglas
Fir bark
|
25.80
|
73.00
|
1.20
|
56.20
|
5.90
|
36.70
|
0.00
|
0.00
|
22.10
|
22.75
|
|
Loblolly
Pine bark
|
33.90
|
54.70
|
0.40
|
56.30
|
5.60
|
37.70
|
0.00
|
0.00
|
21.78
|
22.35
|
|
ENERGY
CROPS
|
|
|
|
|
|
|
|
|
|
|
|
Eucalyptus
Camaldulensis
|
17.82
|
81.42
|
0.76
|
49.00
|
5.87
|
43.97
|
0.30
|
0.01
|
19.42
|
19.46
|
|
Casuarina
|
19.58
|
78.58
|
1.83
|
48.50
|
6.04
|
43.32
|
0.31
|
0.00
|
18.77
|
19.53
|
|
Poplar
|
16.35
|
82.32
|
1.33
|
48.45
|
5.85
|
43.69
|
0.47
|
0.01
|
19.38
|
19.26
|
|
Sudan
Grass
|
18.60
|
72.75
|
8.65
|
44.58
|
5.35
|
39.18
|
1.21
|
0.01
|
17.39
|
17.62
|
|
PROCESSED
BIOMASS
|
|
|
|
|
|
|
|
|
|
|
|
Plywood
|
15.77
|
82.14
|
2.09
|
48.13
|
5.87
|
42.46
|
1.45
|
0.00
|
18.96
|
19.26
|
|
AGRICULTURAL
|
|
|
|
|
|
|
|
|
|
|
|
Peach
Pits
|
19.85
|
79.12
|
1.03
|
53.00
|
5.90
|
39.14
|
0.32
|
0.05
|
20.82
|
21.39
|
|
Walnut
Shells
|
21.16
|
78.28
|
0.56
|
49.98
|
5.71
|
43.35
|
0.21
|
0.01
|
20.18
|
19.68
|
|
Almond
Prunings
|
21.54
|
76.83
|
1.63
|
51.30
|
5.29
|
40.90
|
0.66
|
0.01
|
20.01
|
19.87
|
|
Black
Walnut Prunings
|
18.56
|
80.69
|
0.78
|
49.80
|
5.82
|
43.25
|
0.22
|
0.01
|
19.83
|
19.75
|
|
Corncobs
|
18.54
|
80.10
|
1.36
|
46.58
|
5.87
|
45.46
|
0.47
|
0.01
|
18.77
|
18.44
|
|
Wheat
Straw
|
19.80
|
71.30
|
8.90
|
43.20
|
5.00
|
39.40
|
0.61
|
0.11
|
17.51
|
16.71
|
|
Cotton
Stalk
|
22.43
|
70.89
|
6.68
|
43.64
|
5.81
|
43.87
|
0.00
|
0.00
|
18.26
|
17.40
|
|
Corn
Stover
|
19.25
|
75.17
|
5.58
|
43.65
|
5.56
|
43.31
|
0.61
|
0.01
|
17.65
|
17.19
|
|
Sugarcane
Bagasse
|
14.95
|
73.78
|
11.27
|
44.80
|
5.35
|
39.55
|
0.38
|
0.01
|
17.33
|
17.61
|
|
Rice
Hulls
|
15.80
|
63.60
|
20.60
|
38.30
|
4.36
|
35.45
|
0.83
|
0.06
|
14.89
|
14.40
|
|
Pine
needles
|
26.12
|
72.38
|
1.50
|
48.21
|
6.57
|
43.72
|
|
|
20.12
|
20.02
|
|
Cotton
gin trash
|
15.10
|
67.30
|
17.60
|
39.59
|
5.26
|
36.38
|
2.09
|
0.00
|
16.42
|
15.85
|
|
AQUATIC
BIOMASS
|
|
|
|
|
|
|
|
|
|
|
|
Water
Hyacinth (Florida)
|
-
|
80.40
|
19.60
|
40.30
|
4.60
|
33.99
|
1.51
|
0.00
|
14.86
|
15.54
|
|
Brown
Kelp,Giant, Soquel Point
|
-
|
57.90
|
42.10
|
27.80
|
3.77
|
23.69
|
4.63
|
1.05
|
10.75
|
10.85
|
|
AVERAGE
|
|
|
|
47.91
|
5.74
|
40.98
|
0.52
|
0.05
|
19.11
|
19.15
|
|
LIQUID
FUELS
|
|
|
|
|
|
|
|
|
|
|
|
n-octane
|
0.00
|
-
|
0.00
|
84.10
|
15.90
|
0.00
|
0.00
|
0.00
|
47.80
|
48.09
|
|
Benzene,
C6H6
|
0.00
|
|
|
92.25
|
7.75
|
0.00
|
0.00
|
0.00
|
41.79
|
41.34
|
|
Motor
Gasoline
|
0.00
|
|
|
85.50
|
14.40
|
0.00
|
0.00
|
0.10
|
46.88
|
46.83
|
|
Kerosene
|
0.00
|
|
0.01
|
85.80
|
14.10
|
0.00
|
0.00
|
0.10
|
46.50
|
46.58
|
|
Methanol,
CH3OH
|
0.00
|
|
0.00
|
37.50
|
12.50
|
50.00
|
0.00
|
0.00
|
22.69
|
22.65
|
|
Ethanol,
C2H5OH
|
0.00
|
|
0.00
|
52.20
|
13.00
|
34.80
|
0.00
|
0.00
|
30.15
|
29.94
|
|
PYROLYSIS
OILS
|
|
|
|
|
|
|
|
|
|
|
|
LBL
Wood Oil
|
|
|
0.78
|
72.30
|
8.60
|
17.60
|
0.20
|
0.01
|
33.70
|
33.53
|
|
BOM
wood oil
|
|
|
0.66
|
82.00
|
8.80
|
9.20
|
0.60
|
0.00
|
36.80
|
38.02
|
|
Coke-oven
tar
|
|
|
0.25
|
91.75
|
5.50
|
0.80
|
0.90
|
0.80
|
38.20
|
38.49
|
|
Low
Temp Tar
|
|
|
|
83.00
|
8.20
|
7.40
|
0.60
|
0.80
|
38.75
|
37.94
|
|
SOLID
FUELS
|
|
|
|
|
|
|
|
|
|
|
|
Coal
- Pittsburgh Seam
|
55.80
|
33.90
|
10.30
|
75.50
|
5.00
|
4.90
|
1.20
|
3.10
|
31.75
|
31.82
|
|
Peat,
S-H3
|
26.87
|
70.13
|
3.00
|
54.81
|
5.38
|
35.81
|
0.89
|
0.11
|
22.00
|
21.70
|
|
Charcoal
|
89.31
|
93.88
|
1.02
|
92.04
|
2.45
|
2.96
|
0.53
|
1.00
|
34.39
|
34.78
|
|
Oak
char (565C)
|
55.60
|
27.10
|
17.30
|
64.60
|
2.10
|
15.50
|
0.40
|
0.10
|
23.05
|
23.06
|
|
Casuarina
Char (950C)
|
71.53
|
15.23
|
13.24
|
77.54
|
0.93
|
5.62
|
2.67
|
0.00
|
27.12
|
27.26
|
|
Coconut
Shell Char (750C)
|
87.17
|
9393.00
|
2.90
|
88.95
|
0.73
|
6.04
|
1.38
|
0.00
|
31.12
|
31.21
|
|
Eucalyptus
char (950C)
|
70.32
|
19.22
|
10.45
|
76.10
|
1.33
|
11.10
|
1.02
|
0.00
|
27.60
|
26.75
|
|
ORGANIC
CHEMICALS
|
|
|
M
|
|
|
|
cal/mo
|
cal/g
|
kJ/g
|
|
|
Acetone;
(CH3)2CO
|
|
|
58
|
62.07
|
10.34
|
27.59
|
428
|
7.38
|
30.9
|
31.01
|
|
Acetic
Acid; CH3CO2H
|
|
|
60
|
40.00
|
6.67
|
53.33
|
209
|
3.48
|
14.6
|
16.30
|
|
D-Glucose;
C6H12O6
|
|
|
180
|
40.00
|
6.67
|
53.33
|
670
|
3.72
|
15.6
|
16.30
|
|
Phenol;
C6H5OH
|
|
|
94
|
76.60
|
6.38
|
17.02
|
730
|
7.76
|
32.5
|
32.50
|
|
Cellulose;
C6H10O5
|
|
|
162
|
44.44
|
6.17
|
49.38
|
|
|
|
17.68
|
|
Lignin
(Softwood)
|
|
|
|
63.8
|
6.30
|
29.90
|
|
|
|
26.60
|
|
Lignin
(Hardwood)
|
|
|
|
59.8
|
6.40
|
33.70
|
|
|
|
24.93
|
|
EXCEPTIONS
|
|
|
|
|
|
|
|
|
|
|
|
Hydrogen,
H2
|
|
|
|
0.00
|
100.00
|
0.00
|
0.00
|
0.00
|
141.26
|
117.83
|
|
Carbon
Monoxide, CO
|
|
|
|
42.86
|
0.00
|
57.14
|
0.00
|
0.00
|
10.16
|
9.05
|
|
Acetylene
|
|
|
|
92.25
|
7.75
|
0.00
|
0.00
|
0.00
|
49.60
|
41.34
|
|
Carbon
|
|
|
|
100.00
|
0.00
|
0.00
|
|
|
32.81
|
34.91
|
|
Carbon
dioxide, CO2
|
|
|
|
27.27
|
0.00
|
72.7%
|
|
|
0.00
|
9.45
|
|
Water
|
|
|
|
0.00
|
11.11
|
88.89
|
|
|
0.00
|
3.90
|
(1)
"Thermal Data for Natural and Synthetic Fuels", S.
Gaur and T. Reed, Marcel Dekker, 1998.
|
