Baseline Cost Analysis of Energy Wastewater Treatment with Preliminary Feasibility Analysis of Critical Mineral Recovery

Critical mineral recovery from wastewater is an enhancement of conventional mining that can help meet growing demand. This work investigates two energy wastewaters that have previously been shown to be enriched in critical minerals, oil and gas produced water in the Permian Basin and combustion residual leachate. Treatment of these two wastewaters using reverse osmosis or thermal-based methods concentrates critical minerals, which improves the economic viability of critical mineral recovery. Revenue from mineral recovery could also offset treatment costs for operators. This work evaluates the cost of treatment for each wastewater and evaluates the potential revenue from critical minerals concentrated in the brine. The levelized cost of water for combustion residual leachate ranges from USD 1.90 to USD 16.20 (USD 2023/m³ permeate) and for produced water ranges from USD 14.40 to USD 24.30 (USD 2023/m³ distillate). Recovery opportunities range from USD 0.11 to USD 1.13 (USD 2023/m³ permeate) for leachate and from USD 8.28 to USD 42.10 (USD 2023/m³ distillate) for produced water, dominated by the value of magnesium and lithium. Comparing the maximum value of critical minerals contained in produced water and the maximum treatment costs, the value of critical minerals exceeds the cost of treatment by USD 17.80/m³ distillate, which signals a potential revenue opportunity.