# -*- coding: utf-8 -*-
# BioSTEAM: The Biorefinery Simulation and Techno-Economic Analysis Modules
# Copyright (C) 2020-2023, Yoel Cortes-Pena <yoelcortes@gmail.com>
#
# This module is under the UIUC open-source license. See
# github.com/BioSTEAMDevelopmentGroup/biosteam/blob/master/LICENSE.txt
# for license details.
"""
"""
import flexsolve as flx
import biosteam as bst
import thermosteam as tmo
cost = bst.decorators.cost
__all__ = ('BoilerTurbogenerator',)
#: TODO add reference of NREL
[docs]
@cost('Work', 'Turbogenerator',
CE=551, S=42200, kW=0, cost=9500e3, n=0.60, BM=1.8)
@cost('Flow rate', 'Hot process water softener system',
CE=551, cost=78e3, S=235803, n=0.6, BM=1.8)
@cost('Flow rate', 'Amine addition pkg',
CE=551, cost=40e3, S=235803, n=0.6, BM=1.8)
@cost('Flow rate', 'Deaerator',
CE=551, cost=305e3, S=235803, n=0.6, BM=3.0)
@cost('Flow rate', 'Boiler',
CE=551, cost=28550e3, kW=1371, S=238686, n=0.6, BM=1.8)
@cost('Ash disposal', 'Baghouse bags',
CE=551, cost=466183. / 4363., n=1.0, lifetime=5)
class BoilerTurbogenerator(bst.Facility):
"""
Create a BoilerTurbogenerator object that will calculate electricity
generation from burning the feed. It also takes into account how much
steam is being produced, and the required cooling utility of the turbo
generator. All capital cost correlations are based on [1]_.
Parameters
----------
ins :
* [0] Liquid/solid feed that will be burned.
* [1] Gas feed that will be burned.
* [2] Make-up water.
* [3] Natural gas/fuel to satisfy steam and electricity demand.
* [4] Lime for flue gas desulfurization.
* [5] Boiler chemicals.
* [6] Air or oxygen-rich gas.
outs :
* [0] Total emissions produced.
* [1] Blowdown water.
* [2] Ash disposal.
boiler_efficiency : float, optional
Fraction of heat transferred to steam. Defaults to 0.8.
turbo_generator_efficiency : float, optional
Fraction of steam heat converted to electricity. Defaults to 0.85.
agent : UtilityAgent, optional
Steam produced. Defaults to low pressure steam.
other_agents = () : Iterable[UtilityAgent], optional
Other steams produced. Defaults to all other heating agents.
fuel_source : str, optional
Name fuel used to satisfy steam and electricity demand. Defaults to 'CH4'.
fuel_price : float, optional
Price of natural gas [USD/kg]. Same as `bst.stream_utility_prices['Natural gas']`,
which defaults to 0.218.
ash_disposal_price : float, optional
Price of disposing ash [USD/kg]. Same as `bst.stream_utility_prices['Ash disposal']`,
which defaults to -0.0318.
satisfy_system_electricity_demand : bool, optional
Whether to purchase natural gas to satisfy system electricity demand
if there is not enough heat from process feeds (i.e., inlets 0 and 1).
If True, natural gas is purchased to satisfy system heat and electricity demand
when there is not enough heat from the feed and gas.
If False, natural gas is only purchased to satisfy system heat demand
and electricity will be purchased from the grid if there is not
enough heat from the feeds.
In either case, if there is excess heat from the process feeds,
electricity will still be produced.
boiler_efficiency_basis : str, optional
Basis of boiler efficiency. Defaults to 'LHV' (i.e., lower heating value).
'HHV' (i.e., higher heating value) is also a valid basis.
Examples
--------
Create a boiler-turbogenerator system that uses sugarcane bagasse to
produce steam for a distillation unit and any excess steam for surplus electricity:
>>> import biosteam as bst
>>> from biorefineries import cane
>>> chemicals = cane.create_sugarcane_chemicals()
>>> chemicals.define_group(
... name='Fiber',
... IDs=['Cellulose', 'Hemicellulose', 'Lignin'],
... composition=[0.4704 , 0.2775, 0.2520],
... wt=True, # Composition is given as weight
... )
>>> bst.settings.set_thermo(chemicals)
>>> dilute_ethanol = bst.Stream('dilute_ethanol', Water=1390, Ethanol=590)
>>> bagasse = bst.Stream('bagasse', Water=0.4, Fiber=0.6, total_flow=8e4, units='kg/hr')
>>> with bst.System('sys') as sys:
... D1 = bst.BinaryDistillation('D1', ins=dilute_ethanol, Lr=0.999, Hr=0.89, k=1.25, LHK=('Ethanol', 'Water'))
... BT = bst.BoilerTurbogenerator('BT')
... BT.ins[0] = bagasse
>>> sys.simulate()
>>> BT.show()
BoilerTurbogenerator: BT
ins...
[0] bagasse
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 1.78e+03
Cellulose 139
Hemicellulose 101
Lignin 79.5
[1] -
phase: 'l', T: 298.15 K, P: 101325 Pa
flow: 0
[2] -
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 488
[3] -
phase: 'g', T: 288.71 K, P: 101560 Pa
flow: 0
[4] -
phase: 'l', T: 298.15 K, P: 101325 Pa
flow: 0
[5] -
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Ash 0.567
[6] -
phase: 'g', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): O2 9.85e+03
N2 4.23e+04
outs...
[0] emissions
phase: 'g', T: 394.15 K, P: 101325 Pa
flow (kmol/hr): Water 3.19e+03
CO2 1.98e+03
O2 7.84e+03
N2 4.23e+04
[1] rejected_water_and_blowdown
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 488
[2] ash_disposal
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 0.00944
Ash 0.567
>>> BT.results() # Steam and electricity are produced, so costs are negative
Boiler turbogenerator Units BT
Electricity Power kW -1.31e+05
Cost USD/hr -1.02e+04
Low pressure steam Duty kJ/hr -7.32e+07
Flow kmol/hr -1.89e+03
Cost USD/hr -450
Cooling water Duty kJ/hr -8.42e+07
Flow kmol/hr 5.75e+04
Cost USD/hr 28.1
Fuel (inlet) Flow kg/hr 0
Cost USD/hr 0
Ash disposal (outlet) Flow kg/hr 0.737
Cost USD/hr 0.0234
Design Work kW 1.33e+05
Flow rate kg/hr 2.93e+05
Ash disposal kg/hr 0.737
Purchase cost Baghouse bags USD 81.1
Boiler USD 3.33e+07
Deaerator USD 3.58e+05
Amine addition pkg USD 4.69e+04
Hot process water softener system USD 9.16e+04
Turbogenerator USD 1.94e+07
Total purchase cost USD 5.32e+07
Utility cost USD/hr -1.07e+04
Notes
-----
The flow rate of natural gas, lime, and boiler chemicals (streams 3-5)
is set by the BoilerTurbogenerator object during simulation.
References
----------
.. [1] Humbird, D., Davis, R., Tao, L., Kinchin, C., Hsu, D., Aden, A.,
Dudgeon, D. (2011). Process Design and Economics for Biochemical
Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid
Pretreatment and Enzymatic Hydrolysis of Corn Stover
(No. NREL/TP-5100-47764, 1013269). https://doi.org/10.2172/1013269
"""
ticket_name = 'BT'
network_priority = 1
boiler_blowdown = 0.03
# Reverse osmosis (RO) typically rejects 25% of water, but the boiler-feed water is assumed to come after RO.
# Setting this parameter to a fraction more than zero effectively assumes that this unit accounts for reverse osmosis.
RO_rejection = 0
_N_ins = 7
_N_outs = 3
_units = {'Flow rate': 'kg/hr',
'Work': 'kW',
'Ash disposal': 'kg/hr'}
def __init__(self, ID='', ins=None,
outs=('emissions',
'rejected_water_and_blowdown',
'ash_disposal'),
thermo=None, *,
boiler_efficiency=None,
turbogenerator_efficiency=None,
side_steam=None,
agent=None,
other_agents=None,
fuel_price=None,
natural_gas_price=None,
ash_disposal_price=None,
T_emissions=None,
CO2_emissions_concentration=None,
satisfy_system_electricity_demand=None,
boiler_efficiency_basis=None,
fuel_source=None,
oxygen_rich_gas_composition=None,
):
if boiler_efficiency_basis is None: boiler_efficiency_basis = 'LHV'
if boiler_efficiency is None: boiler_efficiency = 0.80
if turbogenerator_efficiency is None: turbogenerator_efficiency = 0.85
if satisfy_system_electricity_demand is None: satisfy_system_electricity_demand = True
if fuel_source is None: fuel_source = 'CH4'
if oxygen_rich_gas_composition is None: oxygen_rich_gas_composition = dict(O2=21, N2=79, phase='g', units='kg/hr')
if CO2_emissions_concentration is None: CO2_emissions_concentration = 0.055 # Usually between 4 - 7 for biomass and natural gas (https://www.sciencedirect.com/science/article/pii/S0957582021005127)
bst.Facility.__init__(self, ID, ins, outs, thermo)
settings = bst.settings
self.boiler_efficiency_basis = boiler_efficiency_basis
self.agent = agent = agent or settings.get_heating_agent('low_pressure_steam')
self.fuel_source = fuel_source
self.define_utility('Fuel', self.fuel)
self.define_utility('Ash disposal', self.ash_disposal)
self.boiler_efficiency = boiler_efficiency
self.turbogenerator_efficiency = turbogenerator_efficiency
self.steam_utilities = set()
self.power_utilities = set()
self.steam_demand = agent.to_stream()
self.side_steam = side_steam
self.other_agents = [i for i in settings.heating_agents if i is not agent] if other_agents is None else other_agents
self.CO2_emissions_concentration = CO2_emissions_concentration
self.oxygen_rich_gas_composition = oxygen_rich_gas_composition
if T_emissions is not None:
raise ValueError('setting T_emissions is not yet implemented')
# T_emissions should dictate the efficiency of either the boiler or the turbogenerator.
# Note that T_emissions is tied to the energy balance.
self.T_emissions = T_emissions
if natural_gas_price is not None:
self.fuel_price = natural_gas_price
elif fuel_price is not None:
self.fuel_price = fuel_price
if ash_disposal_price is not None: self.ash_disposal_price = ash_disposal_price
self.satisfy_system_electricity_demand = satisfy_system_electricity_demand
def _get_desulfurization_rxn_and_coreactant(self):
try:
return self.desulfurization_reaction, self._ID_lime
except:
chemicals = self.chemicals
CAS_lime = '1305-62-0'
has_common_name = 'Ca(OH)2' in chemicals
if CAS_lime in chemicals or has_common_name:
if not has_common_name: chemicals.set_synonym(CAS_lime, 'Ca(OH)2')
self.desulfurization_reaction = rxn = tmo.Reaction(
'SO2 + Ca(OH)2 + 0.5 O2 -> CaSO4 + H2O', 'SO2', 0.92, chemicals
)
self._ID_lime = ID = 'Ca(OH)2'
return rxn, ID
CAS_lime = '1305-78-8'
has_common_name = 'CaO' in chemicals
if CAS_lime in chemicals or has_common_name:
if not has_common_name: chemicals.set_synonym(CAS_lime, 'CaO')
self.desulfurization_reaction = rxn = tmo.Reaction(
'SO2 + CaO + 0.5 O2 -> CaSO4', 'SO2', 0.92, chemicals
)
self._ID_lime = ID = 'CaO'
return rxn, ID
raise RuntimeError(
"lime is required for boiler, but no chemical 'CaO' or 'Ca(OH)2' "
"available in thermodynamic property package"
)
@property
def emissions(self):
return self.outs[0]
@property
def blowdown_water(self):
return self.outs[1]
@property
def makeup_water(self):
"""[Stream] Makeup water due to boiler blowdown."""
return self.ins[2]
@property
def fuel(self):
"""[Stream] Fuel used to satisfy steam and electricity requirements."""
return self.ins[3]
natural_gas = fuel
@property
def air(self):
"""[Stream] Air or oxygen rich gas used to supply oxygen for combustion."""
return self.ins[6]
oxygen_rich_gas = air
@property
def ash_disposal(self):
"""[Stream] Ash disposal."""
return self.outs[2]
@property
def fuel_price(self):
"""[Float] Price of natural gas, same as `bst.stream_utility_prices['Natural gas']`."""
return bst.stream_utility_prices['Fuel']
@fuel_price.setter
def fuel_price(self, new_price):
bst.stream_utility_prices['Fuel'] = new_price
natural_gas_price = fuel_price
@property
def ash_disposal_price(self):
"""[Float] Price of ash disposal, same as `bst.stream_utility_prices['Ash disposal']`."""
return bst.stream_utility_prices['Ash disposal']
@ash_disposal_price.setter
def ash_disposal_price(self, ash_disposal_price):
bst.stream_utility_prices['Ash disposal'] = ash_disposal_price
def _run(self): pass
def _load_utility_agents(self):
steam_utilities = self.steam_utilities
steam_utilities.clear()
agent = self.agent
units = self.other_units
for agent in (*self.other_agents, agent):
ID = agent.ID
for u in units:
for hu in u.heat_utilities:
agent = hu.agent
if agent and agent.ID == ID:
steam_utilities.add(hu)
self.electricity_demand = sum([u.power_utility.consumption for u in units])
def _design(self):
B_eff = self.boiler_efficiency
TG_eff = self.turbogenerator_efficiency
steam_demand = self.steam_demand
Design = self.design_results
chemicals = self.chemicals
self._load_utility_agents()
mol_steam = sum([i.flow for i in self.steam_utilities])
feed_solids, feed_gas, makeup_water, fuel, lime, chems, oxygen_rich_gas = self.ins
oxygen_rich_gas.empty()
if self.fuel_source == 'CH4':
fuel.phase = 'g'
fuel.set_property('T', 60, 'degF')
fuel.set_property('P', 14.73, 'psi')
emissions, blowdown_water, ash_disposal = self.outs
if not lime.price:
lime.price = 0.19937504680689402
if not chems.price:
chems.price = 4.995862254032183
H_steam = sum([i.duty for i in self.steam_utilities])
side_steam = self.side_steam
if side_steam:
H_steam += side_steam.H
mol_steam += side_steam.F_mol
steam_demand.imol['7732-18-5'] = mol_steam
self.combustion_reactions = combustion_rxns = chemicals.get_combustion_reactions()
non_empty_feeds = [i for i in (feed_solids, feed_gas) if not i.isempty()]
boiler_efficiency_basis = self.boiler_efficiency_basis
fuel_source = self.fuel_source
def calculate_excess_electricity_at_natual_gas_flow(fuel_flow):
if fuel_flow:
fuel_flow = abs(fuel_flow)
fuel.imol[fuel_source] = fuel_flow
else:
fuel.empty()
if boiler_efficiency_basis == 'LHV':
H_combustion = fuel.LHV
for feed in non_empty_feeds: H_combustion += feed.LHV
elif boiler_efficiency_basis == 'HHV':
H_combustion = fuel.HHV
for feed in non_empty_feeds: H_combustion += feed.HHV
else:
raise ValueError(
f"invalid boiler efficiency basis {boiler_efficiency_basis}; "
f"valid values include 'LHV', or 'HHV'"
)
self.H_content = H_content = B_eff * H_combustion
self.H_loss_to_emissions = H_combustion - H_content
H_electricity = H_content - H_steam # Heat available for the turbogenerator
electricity = H_electricity * TG_eff # Electricity produced
self.cooling_duty = electricity - H_electricity
Design['Work'] = work = electricity / 3600
duty_over_mol = 39000 # kJ / mol-superheated steam
self.total_steam = H_content / duty_over_mol #: [float] Total steam produced by the boiler (kmol/hr)
Design['Flow rate'] = flow_rate = self.total_steam * 18.01528
if self.satisfy_system_electricity_demand:
boiler = self.cost_items['Boiler']
rate_boiler = boiler.kW * flow_rate / boiler.S
return work - self.electricity_demand - rate_boiler
else:
return work
self._excess_electricity_without_fuel = excess_electricity = calculate_excess_electricity_at_natual_gas_flow(0)
if excess_electricity < 0:
f = calculate_excess_electricity_at_natual_gas_flow
lb = 0.
fuel.imol[fuel_source] = 1
ub = - excess_electricity * 3600 / fuel.LHV
while f(ub) < 0.:
lb = ub
ub *= 2
flx.IQ_interpolation(f, lb, ub, xtol=1, ytol=1)
if self.cooling_duty > 0.:
# In the event that no electricity is produced and the solver
# solution for natural gas is slightly below the requirement for steam
# (this would lead to a positive duty).
self.cooling_duty = 0.
Design['Work'] = 0.
emissions.T = 298.15 # Will be updated later with the energy balance
emissions.P = 101325
emissions.phase = 'g'
emissions_mol = emissions.mol
emissions_mol[:] = fuel.mol
for feed in non_empty_feeds: emissions_mol[:] += feed.mol
combustion_rxns.force_reaction(emissions_mol)
O2_consumption = -emissions.imol['O2']
oxygen_rich_gas.reset_flow(**self.oxygen_rich_gas_composition)
z_O2 = oxygen_rich_gas.imol['O2'] / oxygen_rich_gas.F_mol
oxygen_rich_gas.F_mol = O2_consumption / z_O2
emissions_mol += oxygen_rich_gas.mol
F_emissions = emissions.F_mass
z_CO2 = emissions.imass['CO2'] / F_emissions
z_CO2_target = self.CO2_emissions_concentration
if z_CO2 > z_CO2_target:
F_emissions_new = z_CO2 * F_emissions / z_CO2_target
dF_emissions = F_emissions_new - F_emissions
oxygen_rich_gas.F_mass = F_mass_O2_new = oxygen_rich_gas.F_mass + dF_emissions
emissions_mol += oxygen_rich_gas.mol * (dF_emissions / F_mass_O2_new)
emissions.H += self.H_loss_to_emissions
hu_cooling = bst.HeatUtility()
hu_cooling(self.cooling_duty, steam_demand.T)
hus_heating = bst.HeatUtility.sum_by_agent(tuple(self.steam_utilities))
for hu in hus_heating: hu.reverse()
self.heat_utilities = [*hus_heating, hu_cooling]
water_index = chemicals.index('7732-18-5')
makeup_water.mol[water_index] = blowdown_water.mol[water_index] = (
self.total_steam * self.boiler_blowdown * 1 / (1 - self.RO_rejection)
)
ash_IDs = [i.ID for i in self.chemicals if not i.formula]
emissions_mol = emissions.mol
SO2_produced = 0
if 'SO2' in chemicals:
SO2_produced += emissions.imol['SO2']
if 'CaSO4' in chemicals:
SO2_produced += emissions.imol['CaSO4']
ash_IDs.append('CaSO4')
if SO2_produced:
rxn, ID_lime = self._get_desulfurization_rxn_and_coreactant()
# FGD lime scaled based on SO2 generated,
# 20% stoichiometric excess based on P52 of ref [1]
rxn.force_reaction(emissions)
lime.imol[ID_lime] = lime_mol = SO2_produced * 1.2
emissions_mol.remove_negatives()
else:
lime.empty()
# About 0.4536 kg/hr of boiler chemicals are needed per 234484 kg/hr steam produced
chems.imol['Ash'] = boiler_chems = 1.9345e-06 * Design['Flow rate']
ash_disposal.empty()
ash_disposal.copy_flow(emissions, IDs=tuple(ash_IDs), remove=True)
ash_disposal.imol['Ash'] += boiler_chems
dry_ash = ash_disposal.F_mass
moisture = min(emissions.imass['Water'], dry_ash * 0.3) # ~20% moisture
ash_disposal.imass['Water'] = moisture
emissions.imass['Water'] -= moisture
Design['Ash disposal'] = dry_ash + moisture
if SO2_produced:
if ID_lime == 'Ca(OH)2': # Ca(OH)2
lime.imol['Water'] = 4 * lime_mol # Its a slurry
else: # CaO
lime.imol['Water'] = 5 * lime_mol
def _cost(self):
self._decorated_cost()
self.power_utility.production = self.design_results['Work']
# Simulation of ethanol production from sugarcane
# in Brazil: economic study of an autonomous
# distillery
# Marina O.S. Diasa,b, Marcelo P. Cunhaa, Charles D.F. Jesusa, Mirna I.G.
# Scandiffioa, Carlos E.V. Rossella,b, Rubens Maciel Filhob, Antonio Bonomia
# a CTBE – Bioethanol Science and Technology National Laboratory, PO Box 6170 –
# CEP 13083-970, Campinas – SP, Brazil, marina.dias@bioetanol.org.br
# b School of Chemical Engineering, University of Campinas, PO Box 6066 – CEP
# 13083-970, Campinas – SP, Brazil
# LHV = 7565 # Bagasse lower heating value (kJ/kg)
