Electrocoagulation Costing Method
Costing Method Parameters
The following parameters are constructed for the unit on the FlowsheetCostingBlock (e.g., m.fs.costing.electrocoagulation)
when applying the cost_electrocoagulation costing method in the watertap_costing_package:
Description |
Symbol |
Parameter Name |
Default Value |
Units |
Notes |
|---|---|---|---|---|---|
Reactor capital cost base parameter |
\(A_r\) |
|
11500 |
\(\text{USD}_{2000}\) |
Parameters from Table 2.1 for Agitated Reactor in Smith (2005) |
Reactor capital cost exponent |
\(b_r\) |
|
0.45 |
\(\text{dimensionless}\) |
Parameters from Table 2.1 for Agitated Reactor in Smith (2005) |
Reactor capital cost material coefficient |
\(x_{r,m}\) |
|
1.0 |
\(\text{dimensionless}\) |
1 for carbon steel; 3.4 for stainless steel; 0.55 for PVC |
Reactor capital cost safety factor |
\(SF_r\) |
|
2.5 |
\(\text{dimensionless}\) |
Developed with feedback from industry experts |
Power supply capital cost equation slope |
\(A_p\) |
|
0.51972 |
\(\text{USD}_{2020}\text{ W}^{-1}\) |
DC power supply + transformer + electrical connection base cost; developed from magna-power.com |
Flocculator capital cost base parameter |
\(A_f\) |
|
1075700 |
\(\text{USD}_{2007}\) |
Figure 5.5.22 in McGivney & Kawamura (2008); refit to power equation |
Flocculator capital cost equation exponent |
\(b_f\) |
|
-0.95139 |
\(\text{dimensionless}\) |
Figure 5.5.22 in McGivney & Kawamura (2008); refit to power equation |
Sludge handling cost |
\(c_{sh}\) |
|
0.0 |
\(\text{USD}\text{ kg}^{-1}\) |
Cost of sludge handling is assumed to be zero by default |
Electrode material cost |
\(c_{mat}\) |
|
2 |
\(\text{USD}_{2021}\text{ kg}^{-1}\) |
Cost per kg for electrode material; 2.23 for Al; 3.41 for Fe |
Electrode material cost safety factor |
\(SF_{mat}\) |
|
2.0 |
\(\text{dimensionless}\) |
Developed with feedback from industry experts |
Costing Method Variables
The following variables are constructed on the unit block (e.g., m.fs.unit.costing) when
applying the cost_electrocoagulation costing method in the watertap_costing_package:
Description |
Symbol |
Variable Name |
Index |
Units |
|---|---|---|---|---|
Capital cost of reactor |
\(C_{r}\) |
|
None |
\(\text{USD}\) |
Capital cost of electrodes |
\(C_{e}\) |
|
None |
\(\text{USD}\) |
Capital cost of power supply |
\(C_{p}\) |
|
None |
\(\text{USD}\) |
Capital cost of floc reactor |
\(C_{f}\) |
|
None |
\(\text{USD}\) |
Annual cost of sludge management |
\(C_{sh}\) |
|
None |
\(\text{USD year}^{-1}\) |
Capital Cost Calculations
Capital costs for electrocoagulation are the summation of the capital cost of the reactor, electrodes, power supply, and flocculator.
The capital cost of the reactor is calculated according to:
The capital cost of the electrodes is calculated from the mass of the electrodes:
The capital cost of the power supply is determined from the power required for the electrocoagulation process:
The flocculator capital cost is a function of the flocculator volume:
Operating Cost Calculations
Operating costs for electrocoagulation are the summation of the electrode replacement, electricity required, and the annual cost of sludge management.
Electricity costs are calculated with the power demand \(P_{tot}\) on an annual basis:
Electrode replacement costs are a function of the dose of coagulant, volumetric flow (on an annual basis), and the cost of the electrode material:
And the annual cost of sludge management is from the total annual mass flow of all non-water components from the byproduct port on the electrocoagulation unit model:
Note: due to the uncertainty in the cost of sludge management, this cost is assumed to be zero by default (i.e., \(c_{sh} = 0\)). The user is encouraged to provide their own value for this parameter if they desire to include it in the costing calculations.