#################################################################################
# WaterTAP Copyright (c) 2020-2024, 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 a membrane evaporation.
"""
import pyomo.environ as pyo
from pyomo.environ import Var, units as pyunits
from idaes.core import declare_process_block_class
from watertap.core import build_sido, constant_intensity, ZeroOrderBaseData
# Some more information about this module
__author__ = "Travis Arnold"
[docs]@declare_process_block_class("MembraneEvaporatorZO")
class MembraneEvaporatorData(ZeroOrderBaseData):
"""
Zero-Order model for a membrane evaporator.
"""
CONFIG = ZeroOrderBaseData.CONFIG()
[docs] def build(self):
super().build()
self._tech_type = "membrane_evaporator"
build_sido(self)
constant_intensity(self)
# Create water flux variable
self.water_flux = Var(
units=pyunits.m / pyunits.hr,
bounds=(0, None),
doc="Water flux through membrane",
)
self._perf_var_dict["Water Flux"] = self.water_flux
self._fixed_perf_vars.append(self.water_flux)
# Create membrane area variable
self.membrane_area = Var(
units=pyunits.m**2, bounds=(0, None), doc="Membrane area"
)
self._perf_var_dict["Membrane Area"] = self.membrane_area
@self.Constraint(self.flowsheet().time, doc="Constraint for water flux.")
def wat_flux(b, t):
return b.properties_byproduct[t].flow_vol == (
pyunits.convert(
b.water_flux * b.membrane_area, to_units=pyunits.m**3 / pyunits.s
)
)
@property
def default_costing_method(self):
return self.cost_membrane_evaporator
[docs] @staticmethod
def cost_membrane_evaporator(blk):
"""
General method for costing membrane evaporator unit.
"""
t0 = blk.flowsheet().time.first()
# Get parameter dict from database
parameter_dict = blk.unit_model.config.database.get_unit_operation_parameters(
blk.unit_model._tech_type, subtype=blk.unit_model.config.process_subtype
)
# Get costing parameter sub-block for this technology
memb_cost = blk.unit_model._get_tech_parameters(
blk,
parameter_dict,
blk.unit_model.config.process_subtype,
["membrane_cost"],
)
# Add cost variable and constraint
blk.capital_cost = pyo.Var(
initialize=1,
units=blk.config.flowsheet_costing_block.base_currency,
bounds=(0, None),
doc="Capital cost of unit operation",
)
expr = pyo.units.convert(
blk.unit_model.membrane_area * memb_cost,
to_units=blk.config.flowsheet_costing_block.base_currency,
)
# Determine if a costing factor is required
blk.costing_package.add_cost_factor(
blk, parameter_dict["capital_cost"]["cost_factor"]
)
blk.capital_cost_constraint = pyo.Constraint(
expr=blk.capital_cost == blk.cost_factor * expr
)
# Register flows
# TODO: Consider adding heat as a registered flow, since the inlet
# stream to the membrane evaporator must be heated to ~37 C.
blk.config.flowsheet_costing_block.cost_flow(
blk.unit_model.electricity[t0], "electricity"
)