Scaling a Methane Eradication Photochemical System for Agricultural Applications

The successful mitigation of anthropogenic methane (CH₄) emissions hinges on the development of technologies that are not only effective but also economically viable at an industrial scale. Building upon previous lab-scale success, this study presents the scaling of an in-situ Methane Eradication Photochemical System (MEPS). The system is built into a shipping container, where air is drawn from a cattle barn and mixed with Cl₂ before entering a 5.5 m³ photochemical chamber. Here, the Cl₂ is photolyzed into chlorine radicals which oxidize CH₄ to CO and CO₂. The treated air is then passed through a scrubber to remove HCl and residual Cl₂. This scaled system was evaluated with airflows ranging from 250 to 1200 m³/hr across various methane concentrations.

The results indicate consistent and robust performance, validating the system's scalability. At relatively high methane concentrations (89 ppm), the system achieved a specific power of 0.33 kWh/gCH₄ and an apparent quantum yield (AQY) of 5.68% at a flow of 243 m³/hr. Performance was maintained at concentrations  of 44 ppm under high-flow conditions (1122 m³/hr), yielding a specific power of 0.53 kWh/gCH₄ and an AQY of 2.3%. Furthermore, the system showed promise against challenging low concentrations (10 ppm at 970 m³/hr), with a specific power of 2.2 kWh/gCH₄.

The successful demonstration of low energy consumption across this range of flow rates and methane levels confirms the scalability of the technology. The possibility of scaling this to a level where it will effectively remove methane from cattle barns seems promising. Ongoing improvements, including the installation of a larger ventilation system, are underway to better understand the operational limits and expand the system's capabilities before scaling for commercialization can happen.