Cost-effectiveness analysis of a regenerative thermal oxidiser for ventilation air methane abatement: Economic evaluation of a 360,000 Nm

This study, developed during the ProVAM Research Project financed by the EU Research Fund for Coal and Steel (RFCS), evaluates the cost-effectiveness of a regenerative thermal oxidiser (RTO) for ventilation air methane (VAM) abatement at a 360,000 m3/h capacity plant. Economic analysis reveals a total capital expenditure (CAPEX) of €9.52 million. Annual operating costs (OPEX) total €0.87 million, primarily driven by electricity consumption (584.1 kW fan power) and maintenance. The system was designed to process 40% of the Pniówek shaft V airflow (890,000 m3/h) with a methane concentration of 0.326%, achieving an annual methane mitigation of 7,236 tonnes. Pniówek Mine is the property of Jastrzębska Spółka Węglowa (JSW) S.A., from Poland. A cash-flow analysis over a 15-year equipment lifespan, using a real after-tax weighted average cost of capital (WACC) of 7.96%, reveals a cost-effectiveness of €274 per tonne of CH4 abated to achieve net present value (NPV) breakeven. Converted to CO2-equivalent (using a 100-year global warming potential of 29.8), this equates to €14.39 per tonne of CO2e. Key operational challenges may include controlling dust and humidity, which require the use of dedusters (€50,141 per module) and dehumidifiers (€214,839 per module) for each of the six reactor modules, each with a capacity of 62,500 m3/h. The RTO demonstrates high destruction efficiency (up to 99%) and thermal efficiency (95–98%), though dust content must remain below 1 mg/Nm3 for non-combustible particles. These results underscore the economic viability of RTO technology for large-scale VAM abatement, particularly at shafts with higher methane concentrations, where economies of scale improve cost efficiency.