Biomass composition

The biocomp() function uses ultimate analysis data to estimate biomass composition in terms of cellulose, hemicellulose, lignins, and extractives. The example below uses the carbon yc and hydrogen yh mass fractions from ultimate analysis data to calculate the cellulose mass fraction on a dry ash-free basis.

>>> yc = 0.534
>>> yh = 0.06
>>> bc = cm.biocomp(yc, yh)
>>> bc['y_daf'][0]
0.293...

The entire biomass composition can be printed to the screen with printcomp=True.

>>> bc = cm.biocomp(yc, yh, printcomp=True)
basis    cell    hemi    ligc    ligh    ligo    tann    tgl
x_daf    0.4118  0.2745  0.0627  0.1529  0.0981  0.0000  0.0000
x_wet    0.4118  0.2745  0.0627  0.1529  0.0981  0.0000  0.0000
y_daf    0.2936  0.1595  0.0713  0.2934  0.1822  0.0000  0.0000
y_wet    0.2936  0.1595  0.0713  0.2934  0.1822  0.0000  0.0000
y_wetash 0.2936  0.1595  0.0713  0.2934  0.1822  0.0000  0.0000

Use the plot_biocomp() function to plot the biomass (triangle symbol) in relation to the reference mixtures (square symbols) as shown below.

# Carbon and hydrogen mass fractions from ultimate analysis
yc = 0.534
yh = 0.06

# Calculate the biomass composition
bc = cm.biocomp(yc, yh)

# Plot the biomass and reference mixtures
fig, ax = plt.subplots(tight_layout=True)
cm.plot_biocomp(ax, yc, yh, bc['y_rm1'], bc['y_rm2'], bc['y_rm3'])

plt.show()
../_images/biomass_composition-1.pdf

Notice that the C and H mass fractions may give negative biomass composition values when the default splitting parameters are used as shown below. This is also depicted by the biomass marker going outside the bounds (dashed triangle) of the reference mixtures.

>>> yc = 0.51
>>> yh = 0.057
>>> _ = cm.biocomp(yc, yh, printcomp=True)
basis    cell    hemi    ligc    ligh     ligo    tann    tgl
x_daf    0.4534  0.3023  0.0489  -0.0106  0.2061  0.0000  -0.0000
x_wet    0.4534  0.3023  0.0489  -0.0106  0.2061  0.0000  -0.0000
y_daf    0.3527  0.1916  0.0605  -0.0223  0.4175  0.0000  -0.0000
y_wet    0.3527  0.1916  0.0605  -0.0223  0.4175  0.0000  -0.0000
y_wetash 0.3527  0.1916  0.0605  -0.0223  0.4175  0.0000  -0.0000

yc = 0.51
yh = 0.057
bc = cm.biocomp(yc, yh)

fig, ax = plt.subplots(tight_layout=True)
cm.plot_biocomp(ax, yc, yh, bc['y_rm1'], bc['y_rm2'], bc['y_rm3'])

plt.show()
../_images/biomass_composition-2.pdf

In this particular case, adjust the epsilon splitting parameter to properly characterize the biomass for the C and H mass fractions.

>>> yc = 0.51
>>> yh = 0.057
>>> _ = cm.biocomp(yc, yh, epsilon=0.4, printcomp=True)
basis    cell    hemi    ligc    ligh    ligo    tann    tgl
x_daf    0.4623  0.3082  0.0259  0.0504  0.0532  0.0998  0.0000
x_wet    0.4623  0.3082  0.0259  0.0504  0.0532  0.0998  0.0000
y_daf    0.3800  0.2064  0.0339  0.1116  0.1140  0.1540  0.0000
y_wet    0.3800  0.2064  0.0339  0.1116  0.1140  0.1540  0.0000
y_wetash 0.3800  0.2064  0.0339  0.1116  0.1140  0.1540  0.0000

yc = 0.51
yh = 0.057
bc = cm.biocomp(yc, yh, epsilon=0.4)

fig, ax = plt.subplots(tight_layout=True)
cm.plot_biocomp(ax, yc, yh, bc['y_rm1'], bc['y_rm2'], bc['y_rm3'])

plt.show()
../_images/biomass_composition-3.pdf