###############################################################################
# WaterTAP Copyright (c) 2021, The Regents of the University of California,
# through Lawrence Berkeley National Laboratory, Oak Ridge National
# Laboratory, National Renewable Energy Laboratory, and National Energy
# Technology Laboratory (subject to receipt of any required approvals from
# the U.S. Dept. of Energy). All rights reserved.
#
# Please see the files COPYRIGHT.md and LICENSE.md for full copyright and license
# information, respectively. These files are also available online at the URL
# "https://github.com/watertap-org/watertap/"
#
###############################################################################
"""
Simple property package for Na-Ca-Mg-SO4-Cl solution represented with salts
"""
from pyomo.environ import (
Constraint,
Var,
Param,
Expression,
Reals,
NonNegativeReals,
Suffix,
)
from pyomo.environ import units as pyunits
# Import IDAES cores
from idaes.core import (
declare_process_block_class,
MaterialFlowBasis,
PhysicalParameterBlock,
StateBlockData,
StateBlock,
MaterialBalanceType,
EnergyBalanceType,
)
from idaes.core.base.components import Component, Solute, Solvent
from idaes.core.base.phases import LiquidPhase
from idaes.core.util.initialization import (
fix_state_vars,
revert_state_vars,
solve_indexed_blocks,
)
from idaes.core.util.model_statistics import (
degrees_of_freedom,
number_unfixed_variables,
)
from idaes.core.util.exceptions import PropertyPackageError
from idaes.core.util.misc import extract_data
import idaes.core.util.scaling as iscale
import idaes.logger as idaeslog
from idaes.core.solvers import get_solver
# Set up logger
_log = idaeslog.getLogger(__name__)
[docs]@declare_process_block_class("PropParameterBlock")
class PropParameterData(PhysicalParameterBlock):
CONFIG = PhysicalParameterBlock.CONFIG()
[docs] def build(self):
"""
Callable method for Block construction.
"""
super(PropParameterData, self).build()
self._state_block_class = PropStateBlock
# phases
self.Liq = LiquidPhase()
# components
self.H2O = Solvent()
self.NaCl = Solute()
self.CaSO4 = Solute()
self.MgSO4 = Solute()
self.MgCl2 = Solute()
# molecular weight
mw_comp_data = {
"H2O": 18.015e-3,
"NaCl": 58.44e-3,
"CaSO4": 136.14e-3,
"MgSO4": 120.37e-3,
"MgCl2": 95.21e-3,
}
self.mw_comp = Param(
self.component_list,
mutable=False,
initialize=extract_data(mw_comp_data),
units=pyunits.kg / pyunits.mol,
doc="Molecular weight",
)
self.dens_mass = Param(
mutable=False,
initialize=1000,
units=pyunits.kg / pyunits.m**3,
doc="Density",
)
self.cp = Param(
mutable=False, initialize=4.2e3, units=pyunits.J / (pyunits.kg * pyunits.K)
)
# ---default scaling---
self.set_default_scaling("temperature", 1e-2)
self.set_default_scaling("pressure", 1e-6)
class _PropStateBlock(StateBlock):
"""
This Class contains methods which should be applied to Property Blocks as a
whole, rather than individual elements of indexed Property Blocks.
"""
def initialize(
self,
state_args=None,
state_vars_fixed=False,
hold_state=False,
outlvl=idaeslog.NOTSET,
solver=None,
optarg=None,
):
"""
Initialization routine for property package.
Keyword Arguments:
state_args : Dictionary with initial guesses for the state vars
chosen. Note that if this method is triggered
through the control volume, and if initial guesses
were not provided at the unit model level, the
control volume passes the inlet values as initial
guess.The keys for the state_args dictionary are:
flow_mass_phase_comp : value at which to initialize
phase component flows
pressure : value at which to initialize pressure
temperature : value at which to initialize temperature
outlvl : sets output level of initialization routine (default=idaeslog.NOTSET)
optarg : solver options dictionary object (default=None)
state_vars_fixed: Flag to denote if state vars have already been
fixed.
- True - states have already been fixed by the
control volume 1D. Control volume 0D
does not fix the state vars, so will
be False if this state block is used
with 0D blocks.
- False - states have not been fixed. The state
block will deal with fixing/unfixing.
solver : Solver object to use during initialization if None is provided
it will use the default solver for IDAES (default = None)
hold_state : flag indicating whether the initialization routine
should unfix any state variables fixed during
initialization (default=False).
- True - states variables are not unfixed, and
a dict of returned containing flags for
which states were fixed during
initialization.
- False - state variables are unfixed after
initialization by calling the
release_state method
Returns:
If hold_states is True, returns a dict containing flags for
which states were fixed during initialization.
"""
# Get loggers
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="properties")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="properties")
# Set solver and options
opt = get_solver(solver, optarg)
# Fix state variables
flags = fix_state_vars(self, state_args)
# Check when the state vars are fixed already result in dof 0
for k in self.keys():
dof = degrees_of_freedom(self[k])
if dof != 0:
raise PropertyPackageError(
"\nWhile initializing {sb_name}, the degrees of freedom "
"are {dof}, when zero is required. \nInitialization assumes "
"that the state variables should be fixed and that no other "
"variables are fixed. \nIf other properties have a "
"predetermined value, use the calculate_state method "
"before using initialize to determine the values for "
"the state variables and avoid fixing the property variables."
"".format(sb_name=self.name, dof=dof)
)
# ---------------------------------------------------------------------
skip_solve = True # skip solve if only state variables are present
for k in self.keys():
if number_unfixed_variables(self[k]) != 0:
skip_solve = False
if not skip_solve:
# Initialize properties
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
results = solve_indexed_blocks(opt, [self], tee=slc.tee)
init_log.info_high(
"Property initialization: {}.".format(idaeslog.condition(results))
)
# ---------------------------------------------------------------------
# If input block, return flags, else release state
if state_vars_fixed is False:
if hold_state is True:
return flags
else:
self.release_state(flags)
def release_state(self, flags, outlvl=idaeslog.NOTSET):
"""
Method to release state variables fixed during initialisation.
Keyword Arguments:
flags : dict containing information of which state variables
were fixed during initialization, and should now be
unfixed. This dict is returned by initialize if
hold_state=True.
outlvl : sets output level of of logging
"""
# Unfix state variables
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="properties")
revert_state_vars(self, flags)
init_log.info_high("{} State Released.".format(self.name))
[docs]@declare_process_block_class("PropStateBlock", block_class=_PropStateBlock)
class PropStateBlockData(StateBlockData):
[docs] def build(self):
"""Callable method for Block construction."""
super(PropStateBlockData, self).build()
self.scaling_factor = Suffix(direction=Suffix.EXPORT)
seawater_mass_frac_dict = {
("Liq", "NaCl"): 2.827e-2,
("Liq", "CaSO4"): 1.298e-3,
("Liq", "MgSO4"): 1.529e-3,
("Liq", "MgCl2"): 4.251e-3,
("Liq", "H2O"): 0.9647,
}
# Add state variables
self.flow_mass_phase_comp = Var(
self.params.phase_list,
self.params.component_list,
initialize=seawater_mass_frac_dict,
bounds=(0.0, 100),
domain=NonNegativeReals,
units=pyunits.kg / pyunits.s,
doc="Mass flow rate",
)
self.temperature = Var(
initialize=298.15,
bounds=(273.15, 1000),
domain=NonNegativeReals,
units=pyunits.degK,
doc="State temperature",
)
self.pressure = Var(
initialize=101325,
bounds=(1e5, 5e7),
domain=NonNegativeReals,
units=pyunits.Pa,
doc="State pressure",
)
# -----------------------------------------------------------------------------
# Property Methods
def _mass_frac_phase_comp(self):
self.mass_frac_phase_comp = Var(
self.params.phase_list,
self.params.component_list,
initialize=0.1,
bounds=(0.0, None),
units=pyunits.dimensionless,
doc="Mass fraction",
)
def rule_mass_frac_phase_comp(b, j):
return b.mass_frac_phase_comp["Liq", j] == b.flow_mass_phase_comp[
"Liq", j
] / sum(
b.flow_mass_phase_comp["Liq", j] for j in self.params.component_list
)
self.eq_mass_frac_phase_comp = Constraint(
self.params.component_list, rule=rule_mass_frac_phase_comp
)
def _flow_vol(self):
self.flow_vol = Var(
initialize=1e-3,
bounds=(0.0, None),
units=pyunits.m**3 / pyunits.s,
doc="Volumetric flow rate",
)
def rule_flow_vol(b):
return (
b.flow_vol
== sum(
b.flow_mass_phase_comp["Liq", j] for j in b.params.component_list
)
/ b.params.dens_mass
)
self.eq_flow_vol = Constraint(rule=rule_flow_vol)
def _flow_mol_phase_comp(self):
self.flow_mol_phase_comp = Var(
self.params.phase_list,
self.params.component_list,
initialize=1,
bounds=(0.0, None),
units=pyunits.mol / pyunits.s,
doc="Molar flowrate",
)
def rule_flow_mol_phase_comp(b, j):
return (
b.flow_mol_phase_comp["Liq", j]
== b.flow_mass_phase_comp["Liq", j] / b.params.mw_comp[j]
)
self.eq_flow_mol_phase_comp = Constraint(
self.params.component_list, rule=rule_flow_mol_phase_comp
)
def _enth_flow(self):
# enthalpy flow expression for get_enthalpy_flow_terms method
temperature_ref = 273.15 * pyunits.K
def rule_enth_flow(b): # enthalpy flow [J/s]
return (
b.params.cp
* sum(b.flow_mass_phase_comp["Liq", j] for j in b.params.component_list)
* (b.temperature - temperature_ref)
)
self.enth_flow = Expression(rule=rule_enth_flow)
# -----------------------------------------------------------------------------
# General Methods
# NOTE: For scaling in the control volume to work properly, these methods must
# return a pyomo Var or Expression
[docs] def get_material_flow_terms(self, p, j):
"""Create material flow terms for control volume."""
return self.flow_mass_phase_comp[p, j]
[docs] def get_enthalpy_flow_terms(self, p):
"""Create enthalpy flow terms."""
return self.enth_flow
# TODO: make property package compatible with dynamics
# def get_material_density_terms(self, p, j):
# """Create material density terms."""
# def get_enthalpy_density_terms(self, p):
# """Create enthalpy density terms."""
def default_material_balance_type(self):
return MaterialBalanceType.componentTotal
def default_energy_balance_type(self):
return EnergyBalanceType.enthalpyTotal
[docs] def get_material_flow_basis(b):
return MaterialFlowBasis.mass
[docs] def define_state_vars(self):
"""Define state vars."""
return {
"flow_mass_phase_comp": self.flow_mass_phase_comp,
"temperature": self.temperature,
"pressure": self.pressure,
}
# -----------------------------------------------------------------------------
# Scaling methods
def calculate_scaling_factors(self):
super().calculate_scaling_factors()
# setting scaling factors for variables
# default scaling factors have already been set with
# idaes.core.property_base.calculate_scaling_factors()
# scaling factors for parameters
for j, v in self.params.mw_comp.items():
if iscale.get_scaling_factor(v) is None:
iscale.set_scaling_factor(self.params.mw_comp[j], 1e2)
if iscale.get_scaling_factor(self.params.dens_mass) is None:
iscale.set_scaling_factor(self.params.dens_mass, 1e-3)
if iscale.get_scaling_factor(self.params.cp) is None:
iscale.set_scaling_factor(self.params.cp, 1e-3)
# these variables should have user input
if iscale.get_scaling_factor(self.flow_mass_phase_comp["Liq", "H2O"]) is None:
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "H2O"], default=1, warning=True
)
iscale.set_scaling_factor(self.flow_mass_phase_comp["Liq", "H2O"], sf)
if iscale.get_scaling_factor(self.flow_mass_phase_comp["Liq", "NaCl"]) is None:
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "NaCl"], default=1e2, warning=True
)
iscale.set_scaling_factor(self.flow_mass_phase_comp["Liq", "Cl"], sf)
if iscale.get_scaling_factor(self.flow_mass_phase_comp["Liq", "CaSO4"]) is None:
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "CaSO4"], default=1e3, warning=True
)
iscale.set_scaling_factor(self.flow_mass_phase_comp["Liq", "CaSO4"], sf)
if iscale.get_scaling_factor(self.flow_mass_phase_comp["Liq", "MgSO4"]) is None:
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "MgSO4"], default=1e3, warning=True
)
iscale.set_scaling_factor(self.flow_mass_phase_comp["Liq", "MgSO4"], sf)
if iscale.get_scaling_factor(self.flow_mass_phase_comp["Liq", "MgCl2"]) is None:
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "MgCl2"], default=1e3, warning=True
)
iscale.set_scaling_factor(self.flow_mass_phase_comp["Liq", "MgCl2"], sf)
# these variables do not typically require user input,
# will not override if the user does provide the scaling factor
if self.is_property_constructed("mass_frac_phase_comp"):
for j in self.params.component_list:
if (
iscale.get_scaling_factor(self.mass_frac_phase_comp["Liq", j])
is None
):
if j == "H2O":
iscale.set_scaling_factor(
self.mass_frac_phase_comp["Liq", j], 1
)
else:
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", j]
) / iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "H2O"]
)
iscale.set_scaling_factor(
self.mass_frac_phase_comp["Liq", j], sf
)
if self.is_property_constructed("flow_vol"):
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", "H2O"]
) / iscale.get_scaling_factor(self.params.dens_mass)
iscale.set_scaling_factor(self.flow_vol, sf)
if self.is_property_constructed("flow_mol_phase_comp"):
for j in self.params.component_list:
if (
iscale.get_scaling_factor(self.flow_mol_phase_comp["Liq", j])
is None
):
sf = iscale.get_scaling_factor(
self.flow_mass_phase_comp["Liq", j]
) / iscale.get_scaling_factor(self.params.mw_comp[j])
iscale.set_scaling_factor(self.flow_mol_phase_comp["Liq", j], sf)
if self.is_property_constructed("enth_flow"):
if iscale.get_scaling_factor(self.enth_flow) is None:
sf = (
iscale.get_scaling_factor(self.params.cp)
* iscale.get_scaling_factor(self.flow_mass_phase_comp["Liq", "H2O"])
* 1e-1
) # temperature change on the order of 1e1
iscale.set_scaling_factor(self.enth_flow, sf)
# transforming constraints
# property relationships with no index, simple constraint
v_str_lst_simple = ["flow_vol"]
for v_str in v_str_lst_simple:
if self.is_property_constructed(v_str):
v = getattr(self, v_str)
sf = iscale.get_scaling_factor(v, default=1, warning=True)
c = getattr(self, "eq_" + v_str)
iscale.constraint_scaling_transform(c, sf)
# property relationships indexed by component and phase
v_str_lst_phase_comp = ["mass_frac_phase_comp", "flow_mol_phase_comp"]
for v_str in v_str_lst_phase_comp:
if self.is_property_constructed(v_str):
v_comp = getattr(self, v_str)
c_comp = getattr(self, "eq_" + v_str)
for j, c in c_comp.items():
sf = iscale.get_scaling_factor(
v_comp["Liq", j], default=1, warning=True
)
iscale.constraint_scaling_transform(c, sf)