Evaporation Pond (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

Electricity consumption is calculated using the constant_intensity helper function. See documentation for Helper Methods for Electricity Demand.

Costing Method

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

Additional Variables

Description	Variable Name	Units
Air temperature	air_temperature	\(K\)
Daily solar radiation incident	solar_radiation	\(mJ/m^2\)
Pond dike height	dike_height	\(ft\)
Factor to adjust evaporation rate of pure water	evaporation_rate_adj_factor	\(dimensionless\)
Evaporation rate calculation parameter A	evap_rate_calc_a_parameter	\(mm/d\)
Evaporation rate calculation parameter B	evap_rate_calc_b_parameter	\(m^2/mJ\)
Evaporation rate calculation parameter C	evap_rate_calc_c_parameter	\(m^2/mJ\)
Adjusted area calculation parameter A	adj_area_calc_a_parameter	\(acre\)
Adjusted area calculation parameter B	adj_area_calc_b_parameter	\(dimensionless\)
Pond area needed based on evaporation rate	area	\(acre\)
Adjusted pond area needed	adj_area	\(acre\)
Calculated evaporation rate of pure water	evaporation_rate_pure	\(mm/d\)
Pure water evaporation rate adjusted for salinity	evaporation_rate_salt	\(gal/acre/min\)

Additional Constraints

Description	Constraint Name
Evaporation rate of pure water constraint	evap_rate_pure_constraint
Adjusted evaporation rate for salinity constraint	evap_rate_salt_constraint
Base area constraint	area_constraint
Adjusted area constraint	area_adj_constraint

Class Documentation

This module contains a zero-order representation of an evaporation pond unit model.

class watertap.unit_models.zero_order.evaporation_pond_zo.EvaporationPondZO(*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

• 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:

(EvaporationPondZO) New instance

class watertap.unit_models.zero_order.evaporation_pond_zo.EvaporationPondZOData(component)

Zero-Order model for a evaporation pond unit.

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

static cost_evaporation_pond(blk)

General method for costing evaporation pond. Capital cost is based on the pond area and other pond construction parameters.