Zero Order Unit Model Base Class

The zero-order unit model base class is intended to form the basis for a library of generic zero-order type (fixed performance) unit models. It defines a standard API for these types of unit operations and a set of common helper methods for building and working with these.

Usage

Ther ZeroOrderBaseData class contains no variables or constraints of its own - rather it is intended to be used as the starting point for construction of zero-order type models for specific unit operations.

The code below shows an outline of how the ZeroOrderBaseData class is intended to be used to develop custom zero-order type models.

from idaes.core import declare_process_block_class
from watertap.core import ZeroOrderBaseData

@declare_process_block_class("MyZOUnit")
class MyZOUnitData(ZeroOrderBaseData):

  CONFIG = ZeroOrderBaseData.CONFIG()

  def build(self):
      super().build()

      self._tech_type = "my_technology"

      # Add necessary StateBlocks, Ports, Variables and Constraints
      # A library of methods for common model form is available,
      # or users can custom code their own components

Property Package Requirements

The ZeroOrderBase class makes a number of assumptions about the structure of the associated property package, and contains a number of checks to ensure the property package meets these requirements. The requirements for the property package are:

1. A single phase named Liq.

2. A single Solvent species named H2O (package must define a solvent_set with length one that contains “H2O”).

3. All other species are defined as Solutes (package must define a solute_set and the component_list must be the union of solvent_set and solute_set).

4. The property package must define flow_vol, conc_mass_comp, pressure and temperature as properties.

Class Documentation

class watertap.core.zero_order_base.ZeroOrderBaseData(component)

Standard base class for zero order unit models.

This class contains the basic consistency checks and common methods for zero order type models.

build()

General build method for UnitModelBlockData. This method calls a number of sub-methods which automate the construction of expected attributes of unit models.

Inheriting models should call super().build.

Parameters

None –

Returns

None

calculate_scaling_factors()

Placeholder scaling routine, should be overloaded by derived classes

initialize_build(state_args=None, outlvl=0, solver=None, optarg=None)

Placeholder initialization routine, raises NotImplementedError

load_parameters_from_database(use_default_removal=False)

Method to load parameters for from database.

Parameters

- (use_default_removal) – default removal fraction if no specific value defined in database

Returns

None

set_param_from_data(parameter, data, index=None, use_default_removal=False)

General method for setting parameter values from a dict of data returned from a database.

Parameters

• database (data - dict of parameter values from) –

• database –

• - (use_default_removal) –

• - – default removal fraction if no specific value defined in database

Returns

None

Raises

KeyError if values cannot be found for parameter in data dict –

set_recovery_and_removal(data, use_default_removal=False)

Common utility method for setting values of recovery and removal fractions.

Parameters

• variables (data - dict of parameter values to use when fixing) –

• - (use_default_removal) – default removal fraction if no specific value defined in database

Returns

None