Electrocoagulation (ZO)

Model Type

This unit model is formulated as a single-input, double-output model form. See documentation for single-input, double-output Helper Methods.

Electricity Consumption

The constraint used to calculate energy consumption is described in the Additional Constraints section below. More details can be found in the unit model class.

Costing Method

Costing is calculated using the cost_electrocoagulation() method. For full details on costing, see documentation for the zero-order costing package.

Additional Variables

Description	Variable Name	Units
Cathode area	cathode_area	\(m^2\)
Anode area	anode_area	\(m^2\)
Electrode thickness	electrode_thick	\(m\)
Electrode mass	electrode_mass	\(kg\)
Electrode volume	electrode_volume	\(m^3\)
Electrode gap	electrode_gap	\(m\)
Conductivity	conductivity	\(S/m\)
Applied current	applied_current	\(A\)
Current efficiency	current_efficiency	\(dimensionless\)
Cell voltage	cell_voltage	\(V\)
Overpotential	overpotential	\(V\)
Reactor volume	reactor_volume	\(m^3\)
Metal dose	metal_dose	\(kg/L\)
Ohmic resistance of solution	ohmic_resistance	\(Ω\)
Charge loading rate	charge_loading_rate	\(C/l\)
Current density	current_density	\(A/m^2\)
Power required	power_required	\(W\)
Floc basin volume	floc_basin_vol	\(m^3\)
Floc retention time	floc_retention_time	\(min\)
Overpotential calculation	eq_overpotential

Additional Constraints

Description	Constraint Name
Charge loading rate equation	eq_charge_loading_rate
Total current required	eq_applied_current
Total electrode area required	eq_electrode_area_total
Cell voltage	eq_cell_voltage
Electrode volume	eq_electrode_volume
Cathode/Anode area	eq_cathode_anode
Total reactor volume	eq_reactor_volume
Total flocculation tank volume	eq_floc_reactor_volume
Ohmic resistance	eq_ohmic_resistance
Electrode mass	eq_electrode_mass
Power required	eq_power_required

Class Documentation

This module contains a zero-order representation of an electrocoagulation unit.

class watertap.unit_models.zero_order.electrocoagulation_zo.ElectrocoagulationZO(*args, **kwds)

Parameters:

• rule (function) – A rule function or None. Default rule calls build().

• concrete (bool) – If True, make this a toplevel model. Default - False.

• ctype (class) –

  Pyomo ctype of the block. Default - pyomo.environ.Block

  Config args

  dynamic

  All zero-order models are steady-state only

  has_holdup

  Zero order models do not include holdup

  property_package

  Property parameter object used to define property calculations, default - useDefault. Valid values: { useDefault - use default package from parent model or flowsheet, PhysicalParameterObject - a PhysicalParameterBlock object.}

  property_package_args

  A ConfigBlock with arguments to be passed to a property block(s) and used when constructing these, default - None. Valid values: {see property package for documentation.}

  database

  An instance of a WaterTAP Database to use for parameters.

  process_subtype

  Process subtype to use when looking up parameters from database.

  isothermal

  Isothermal assumption, or ignore temperature variables in unit. Default=True

  isobaric

  Isobaric assumption, or ignore pressure variables in unit. Default=True

  electrode_material

  Electrode material

  reactor_material

  Reactor material

  overpotential_calculation

  Determination of overpotential

• initialize (dict) – ProcessBlockData config for individual elements. Keys are BlockData indexes and values are dictionaries with config arguments as keys.

• idx_map (function) – Function to take the index of a BlockData element and return the index in the initialize dict from which to read arguments. This can be provided to override the default behavior of matching the BlockData index exactly to the index in initialize.

Returns:

(ElectrocoagulationZO) New instance

class watertap.unit_models.zero_order.electrocoagulation_zo.ElectrocoagulationZOData(component)

Zero-order model for an electrocoagulation unit operation.

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

static cost_electrocoagulation(blk)

General method for costing electrocoagulation.

class watertap.unit_models.zero_order.electrocoagulation_zo.ElectrodeMaterial(value)

Electrode material can be aluminum or iron. Default is aluminum. To run the model with iron electrodes, use ElectrocoagulationZO(electrode_material="iron"); otherwise ElectrocoagulationZO() will default to aluminum electrodes.

class watertap.unit_models.zero_order.electrocoagulation_zo.OverpotentialCalculation(value)

An enumeration.

class watertap.unit_models.zero_order.electrocoagulation_zo.ReactorMaterial(value)

Reactor material can be PVC or stainless steel. Default is PVC. To run the model with stainless steel, use ElectrocoagulationZO(reactor_material="stainless_steel"); otherwise, ElectrocoagulationZO() will default to PVC.