=================================
Lignocellulosic Biomass Processes
=================================

The `cellulosic` module contains units and systems specific to lignocellulosic 
biomass processing. Various pretreatment and fermentation systems
are available for users to plug and play.

.. toctree::
   :maxdepth: 2
   :hidden:
   
   chemicals
   systems
   units

Getting Started
---------------

One full biorefinery configuration is available in this module, a corn stover biorefinery 
design for the production of cellulosic ethanol. With the exception of the on-site enzyme
production, this configuration follows all assumptions from a study by Humbird et. al. executed with Aspen 
plus [1]_.  In contrast to the original report by Humbird et al., the cellulase mixture is bought at 
the same concentration of 50 g·L–1 and at a price of 0.424 $·kg–1, which is 
the back-calculated cost of on-site enzyme production as reported in the 
benchmark study. Please checkout the original BioSTEAM manuscript [2]_ for additional details.

.. code-block:: python

    >>> from biorefineries import cellulosic
    >>> cs = cellulosic.Biorefinery('corn stover ethanol')
    >>> cs.chemicals # All chemicals used by the biorefinery.
    CompiledChemicals([Water, Ethanol, AceticAcid, Furfural, Glycerol, H2SO4, LacticAcid, SuccinicAcid, P4O10, HNO3, Denaturant, DAP, AmmoniumAcetate, AmmoniumSulfate, NaNO3, Oil, HMF, N2, NH3, O2, CH4, H2S, SO2, CO2, NO2, NO, CO, Glucose, Xylose, Sucrose, CaSO4, Mannose, Galactose, Arabinose, CellulaseNutrients, Extract, Acetate, Tar, CaO, Ash, NaOH, Lignin, SolubleLignin, GlucoseOligomer, GalactoseOligomer, MannoseOligomer, XyloseOligomer, ArabinoseOligomer, Z_mobilis, T_reesei, Biomass, Cellulose, Protein, Enzyme, Glucan, Xylan, Xylitol, Cellobiose, CSL, DenaturedEnzyme, Arabinan, Mannan, Galactan, WWTsludge, Cellulase])
    >>> cs.cornstover_sys.show() # The main biorefinery system
    System: cornstover_sys
    ins...
    [0] cornstover
        phase: 'l', T: 298.15 K, P: 101325 Pa
        flow (kmol/hr): Water     1.17e+03
                        Sucrose   1.9
                        Extract   68.5
                        Acetate   25.4
                        Ash       4.16e+03
                        Lignin    87.3
                        Protein   114
                        ...
    [1] denaturant
        phase: 'l', T: 298.15 K, P: 101325 Pa
        flow (kmol/hr): Denaturant  4.14
    outs...
    [0] ethanol
        phase: 'l', T: 339.28 K, P: 101325 Pa
        flow (kmol/hr): Water       9.84
                        Ethanol     463
                        Denaturant  4.14
    >>> cs.cornstover_tea.show() # The TEA object
    CellulosicEthanolTEA: cornstover_sys
     NPV: -190,889 USD at 10.0% IRR
    >>> cs.flowsheet # The complete flowsheet
    <Flowsheet: cornstover>
    >>> cs.R303.show() # Any unit operations and streams can be accessed
    SaccharificationAndCoFermentation: R303
    ins...
    [0] slurry  from  ContinuousPresaccharification-R301
        phase: 'l', T: 321.15 K, P: 101325 Pa
        flow (kmol/hr): Water              1.9e+04
                        AceticAcid         19.5
                        Furfural           2.67
                        AmmoniumSulfate    18.3
                        HMF                2.45
                        Glucose            19.9
                        Xylose             112
                        ...
    [1] s23  from  SeedHoldTank-T301
        phase: 'l', T: 305.15 K, P: 101325 Pa
        flow (kmol/hr): Water              1.89e+03
                        Ethanol            44.9
                        AceticAcid         1.95
                        Furfural           0.267
                        Glycerol           0.189
                        SuccinicAcid       0.368
                        DAP                0.0825
                        ...
    [2] CSL2  from  MockSplitter-S302
        phase: 'l', T: 298.15 K, P: 101325 Pa
        flow (kmol/hr): CSL  28.9
    [3] DAP2  from  MockSplitter-S301
        phase: 'l', T: 298.15 K, P: 101325 Pa
        flow (kmol/hr): DAP  1.04
    outs...
    [0] s24  to  Mixer-M304
        phase: 'g', T: 305.15 K, P: 101325 Pa
        flow (kmol/hr): Water         15.3
                        Ethanol       3.95
                        AceticAcid    0.0306
                        Furfural      0.0134
                        Glycerol      1.52e-07
                        LacticAcid    9.36e-06
                        SuccinicAcid  2.47e-08
                        ...
    [1] s25  to  Mixer-M401
        phase: 'l', T: 305.15 K, P: 101325 Pa
        flow (kmol/hr): Water              1.89e+04
                        Ethanol            459
                        AceticAcid         19.5
                        Furfural           2.66
                        Glycerol           1.85
                        LacticAcid         18.4
                        SuccinicAcid       3.61
                        ...
    [2] s20  to  SeedTrain-R302
        phase: 'l', T: 321.15 K, P: 101325 Pa
        flow (kmol/hr): Water              1.89e+03
                        AceticAcid         1.95
                        Furfural           0.267
                        AmmoniumSulfate    1.83
                        HMF                0.245
                        Glucose            16.6
                        Xylose             11.2
                        ...


References
----------
.. [1] Humbird, D.; Davis, R.; Tao, L.; Kinchin, C.; Hsu, D.; Aden, A.; Schoen, 
    P.; Lukas, J.; Olthof, B.; Worley, M.; Sexton, D.; Dudgeon, D. Process 
    Design and Economics for Biochemical Conversion of Lignocellulosic Biomass 
    to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn 
    Stover, Technical Report NREL/TP-5100-47764; DOE: NREL, 2011.

.. [2] Cortes-Peña, Y.; Kumar, D.; Singh, V.; Guest, J. S.
    BioSTEAM: A Fast and Flexible Platform for the Design, Simulation, and 
    Techno-Economic Analysis of Biorefineries under Uncertainty. 
    ACS Sustainable Chem. Eng. 2020. https://doi.org/10.1021/acssuschemeng.9b07040.