Estimating the Capital Costs of Electrowinning Processes

Abstract

Novel electrolysis processes remain strong technological contenders for advances in sustainable materials processing, in particular metals, yet will need to compete economically with currently-deployed production facilities. To evaluate the technoeconomic efficacy of new electrolytic metal extraction processes, an understanding of the capital and operating costs of electrowinning is necessary. Estimation of electrochemical operating costs has been afforded due attention, yet capital cost (CAPEX) trends are far less understood. Herein, we attempt to show that estimating the capital costs of electrowinning processes via conventional chemical engineering scaling laws is not possible. Instead, we propose a capital cost model for electrochemical processes based on relevant operating parameters such as current density, temperature, and voltage. The new model for capital cost describes within ±30 to 100% the capex for existing electrochemical processes, sufficient for order of magnitude and preliminary design capital cost estimation.

Halogen-Mediated Methane Pyrolysis for CO2-Free Hydrogen Production

“…The capital costs of these large facilities are approximately $1/kg Cl 2 /y (∼$3500/kWatt input ) or $35/kg H 2 /y and greater. 52,53 This total capital investment is closer to the actual costs of water electrolysis facilities competed so far and provides further evidence that the aspirational cost targets of the electrolysis community will be long in coming and that our estimate is low. The energy usage in chloralkali is approximately 2.1−2.7 kWh/kg Cl 2 or approximately 88 kWh/ kg H 2 .…”

Electrochemical Chlor-Iron Process for Iron Production from Iron Oxide and Seawater

“…A technoeconomic analysis of the levelized cost of electrolytic iron assumed plants constructed at a similar capital cost to existing chlor-alkali plants (Figure 4E) (20,41). We justify this assumption based on the similar operating conditions and bill of materials of the chlor-iron and chlor-alkali processes.…”

“…Cr1-xFex) (19), then the electrochemical cell does not produce primary GHG emissions-as opposed to cells using sacrificial carbon anodes, such as in the Hall-Heroult process used to refine aluminum (16). The high-temperature and corrosive environment in these processes leads to stringent material requirements and thus increased capital costs of the plant relative to low-temperature cells (20). Processes with molten electrolytes are also less tolerant to shutdowns, which may limit their use their capacity to participate in demand response or their ability to directly integrate, "behind-themeter", with electricity derived from wind and sunlight (21,22).…”

A critical review on the practical use of lithium cycle as an upfront nitrogen removal technology from natural gas

“…The authors developed and the detailed cost analysis of the Li-Cy based on the process parameters extracted from Li and colleagues. 16,26,42,44,[91][92][93] Although Pal et al 90 resultsdo show that employing the Li-Cy on the LNG plant is feasible, several comments can be observed. First, some of the process parameters, such as the lithium bed L/D ratio and porosity, were assumed to be equal to beds from other studies that do not involve lithium.…”

“…A more detailed technoeconomic analysis of using the Li‐Cy was recently conducted by Pal et al 90 and their findings are summarized in Table 8, which includes the profits calculated for the UNR in the range 12.5%–87.5% compared to the basic scenario where the stream is directly fed to the liquefaction cycle. The authors developed and the detailed cost analysis of the Li‐Cy based on the process parameters extracted from Li and colleagues 16,26,42,44,91‐93 . Although Pal et al 90 resultsdo show that employing the Li‐Cy on the LNG plant is feasible, several comments can be observed.…”