Updates to EC ZO model (watertap-org#1164)

* ec model updates

* minor edits

* overpotential calc options

* overpotential constants in yml

* edits for draft PR

* run black, add electrolysis_time Expression

* rel=1e-2 for pytest

* update EC yaml entries

* add scaling for EC; minor changes to EC costing

* update test, add scaling test

* change costing year for EC reactor to 2000

* update EC docs

* add test for overpotential_calculation= calculated

* run black

---------

Co-authored-by: Mukta Hardikar <[email protected]>
Co-authored-by: MuktaHardikar <[email protected]>

docs/technical_reference/unit_models/zero_order_unit_models/electrocoagulation_zo.rst

@@ -21,27 +21,26 @@ Additional Variables
 .. csv-table::
    :header: "Description", "Variable Name", "Units"
 
-   "Electrode width", "electrode_width", ":math:`m`"
-   "Electrode height", "electrode_height", ":math:`m`"
+   "Cathode area", "cathode_area", ":math:`m^2`"
+   "Anode area", "anode_area", ":math:`m^2`"
    "Electrode thickness", "electrode_thick", ":math:`m`"
    "Electrode mass", "electrode_mass", ":math:`kg`"
-   "Total electrode area", "electrode_area_total", ":math:`m^2`"
-   "Electrode area", "electrode_area_per", ":math:`m^2`"
-   "Electrode volume", "electrode_volume_per", ":math:`m^3`"
+   "Electrode volume", "electrode_volume", ":math:`m^3`"
    "Electrode gap", "electrode_gap", ":math:`m`"
-   "Electrolysis time", "electrolysis_time", ":math:`min`"
-   "Number of electrode pairs", "number_electrode_pairs", ":math:`dimensionless`"
-   "Number of cells", "number_cells", ":math:`dimensionless`"
+   "Conductivity", "conductivity", ":math:`S/m`"
    "Applied current", "applied_current", ":math:`A`"
    "Current efficiency", "current_efficiency", ":math:`dimensionless`"
    "Cell voltage", "cell_voltage", ":math:`V`"
    "Overpotential", "overpotential", ":math:`V`"
-   "Reactor volume total (electrochemical + flotation + sedimentation)", "reactor_volume", ":math:`m^3`"
-   "Metal loading", "metal_loading", ":math:`kg/l`"
+   "Reactor volume", "reactor_volume", ":math:`m^3`"
+   "Metal dose", "metal_dose", ":math:`kg/L`"
    "Ohmic resistance of solution", "ohmic_resistance", ":math:`Ω`"
    "Charge loading rate", "charge_loading_rate", ":math:`C/l`"
    "Current density", "current_density", ":math:`A/m^2`"
    "Power required", "power_required", ":math:`W`"
+   "Floc basin volume", "floc_basin_vol", ":math:`m^3`"
+   "Floc retention time", "floc_retention_time", ":math:`min`"
+   "Overpotential calculation", "eq_overpotential"
 
 Additional Constraints
 ----------------------
@@ -50,15 +49,13 @@ Additional Constraints
    :header: "Description", "Constraint Name"
 
    "Charge loading rate equation", "eq_charge_loading_rate"
-   "Metal loading equation", "eq_metal_loading_rate"
    "Total current required", "eq_applied_current"
    "Total electrode area required", "eq_electrode_area_total"
    "Cell voltage", "eq_cell_voltage"
-   "Area per electrode", "eq_electrode_area_per"
-   "Electrode width", "eq_electrode_width"
-   "Electrode height", "eq_electrode_height"
-   "Electrode volume", "eq_electrode_volume_per"
+   "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"

watertap/data/techno_economic/electrocoagulation.yaml

@@ -1,28 +1,34 @@
 default:
+  conductivity:
+    value: 1
+    units: S/m
   electrode_thick:
     value: 0.001
     units: m
   current_density:
     value: 100
     units: A / m^2
-  electrolysis_time:
-    value: 30
-    units: min
-  metal_loading:
+  metal_dose:
     value: 0.0001
     units: kg/L
-  number_electrode_pairs:
-    value: 10
-    units: dimensionless
   electrode_gap:
     value: 0.005
     units: m
   current_efficiency:
     value: 1.
     units: dimensionless
+  floc_retention_time:
+    value: 12
+    units: min
   overpotential:
     value: 1.5
     units: volt
+  overpotential_k1:
+    value: 0.430
+    units: volt
+  overpotential_k2:
+    value: 1
+    units: volt
   recovery_frac_mass_H2O:
     value: 0.99
     units: dimensionless
@@ -34,9 +40,10 @@ default:
       value: 0.7
       units: dimensionless
   capital_cost:
+    cost_factor: TPEC
     ec_reactor_cap_base:
       value: 11500
-      units: USD_2020
+      units: USD_2000
       reference: Saad et al., 2022 - doi.org/10.1016/j.jksus.2022.102015; Smith, 2005 - doi.org/10.1205/cherd.br.0509
     ec_reactor_cap_exp:
       value: 0.45
@@ -49,43 +56,23 @@ default:
     ec_reactor_cap_safety_factor:
       value: 2.5
       units: dimensionless
-    ec_admin_lab_cap_base:
-      value: 69195
-      units: USD_2010
-      reference: Sharma (2010) - doi.org/10.1016/j.envadv.2020.100029 
-    ec_admin_lab_cap_exp:
-      value: 0.5523
-      units: dimensionless
-      reference: Sharma (2010) - doi.org/10.1016/j.envadv.2020.100029 
     ec_power_supply_base_slope:
       value: 0.51972
       units: USD_2020/ W
       reference: https://magna-power.com/
-    ec_admin_lab_op_base:
-      value: 88589
-      units: USD_2010 / year
-      reference: Sharma (2010) - doi.org/10.1016/j.envadv.2020.100029 
-    ec_admin_lab_op_exp:
-      value: 0.4589
-      units: dimensionless
-      reference: Sharma (2010) - doi.org/10.1016/j.envadv.2020.100029 
     sludge_handling_cost:
       value: 0
       units: USD_2020 / kg
-    ec_labor_maint_factor:
-      value: 0.063
-      units: USD_2020 / m^3
-      reference: Sharma (2010) - doi.org/10.1016/j.envadv.2020.100029 
-    current_per_reactor:
-      value: 3000
-      units: ampere
-    number_redundant_reactors:
-      value: 2
-      units: dimensionless
     electrode_material_cost:
       value: 2
       units: USD_2020 / kg
     electrode_material_cost_coeff:
       value: 2
       units: dimensionless
+    capital_floc_a_parameter:
+      value: 952902
+      units: USD_2007/Mgallons
+    capital_floc_b_parameter:
+      value: 177335
+      units: USD_2007