###############################################################################
# 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/"
#
###############################################################################
"""
This module contains a zero-order representation of an ion exchange unit
operation.
"""
from pyomo.environ import Reference, units as pyunits, Var
from idaes.core import declare_process_block_class
from watertap.core import build_sido, pump_electricity, ZeroOrderBaseData
# Some more information about this module
__author__ = "Adam Atia"
[docs]@declare_process_block_class("IonExchangeZO")
class IonExchangeZOData(ZeroOrderBaseData):
"""
Zero-Order model for an Ion exchange unit operation.
"""
CONFIG = ZeroOrderBaseData.CONFIG()
[docs] def build(self):
super().build()
self._tech_type = "ion_exchange"
build_sido(self)
self._Q = Reference(self.properties_in[:].flow_vol)
pump_electricity(self, self._Q)
# mutable parameter; default value found in WT3 for anion exchange
if self.config.process_subtype == "clinoptilolite":
pass
else:
self.eta_pump.set_value(0.8)
# mutable parameter; default value of 2 bar converted to feet head
self.lift_height.set_value(69.91052 * pyunits.feet)
# Add variables and constraints for material requirements
self.NaCl_flowrate = Var(
self.flowsheet().time,
initialize=1,
units=pyunits.kg / pyunits.s,
bounds=(0, None),
doc="Flowrate of NaCl addition",
)
self.NaCl_dose = Var(
units=pyunits.kg / pyunits.m**3,
bounds=(0, None),
doc="Dosage of NaCl addition",
)
self._fixed_perf_vars.append(self.NaCl_dose)
self._perf_var_dict["NaCl Addition"] = self.NaCl_flowrate
@self.Constraint(self.flowsheet().time)
def NaCl_constraint(blk, t):
return blk.NaCl_flowrate[t] == blk.NaCl_dose * blk.properties_in[t].flow_vol
self.resin_demand = Var(
self.flowsheet().time,
initialize=1,
units=pyunits.kg / pyunits.s,
bounds=(0, None),
doc="Replacement rate of ion exchange resin",
)
self.resin_replacement = Var(
units=pyunits.kg / pyunits.m**3,
bounds=(0, None),
doc="Resin replacement as a function of flow",
)
self._fixed_perf_vars.append(self.resin_replacement)
self._perf_var_dict["Resin Demand"] = self.resin_demand
@self.Constraint(self.flowsheet().time)
def resin_constraint(blk, t):
return (
blk.resin_demand[t]
== blk.resin_replacement * blk.properties_in[t].flow_vol
)
if self.config.process_subtype == "clinoptilolite":
if "ammonium_as_nitrogen" in self.config.property_package.solute_set:
self.nitrogen_clay_ratio = Var(
self.flowsheet().config.time,
units=pyunits.dimensionless,
doc="Mass fraction of nitrogen in clay mixture",
)
self._fixed_perf_vars.append(self.nitrogen_clay_ratio)
self.final_solids_mass = Var(
self.flowsheet().config.time,
units=pyunits.kg / pyunits.s,
doc="Solids mass flow in byproduct stream",
)
@self.Constraint(
self.flowsheet().time,
doc="Solids mass flow in byproduct stream constraint",
)
def solids_mass_flow_constraint(b, t):
return (
b.final_solids_mass[t]
== b.properties_byproduct[t].flow_mass_comp[
"ammonium_as_nitrogen"
]
/ b.nitrogen_clay_ratio[t]
)
self._perf_var_dict[
"Nitrogen-Clay Mixture Ratio (kg/kg)"
] = self.nitrogen_clay_ratio
self._perf_var_dict[
"Final mass flow of clay and nitrogen (kg/s)"
] = self.final_solids_mass
else:
raise KeyError(
"ammonium_as_nitrogen should be defined in solute_list for this subtype."
)