TY - JOUR

T1 - A high efficiency gas phase photoreactor for eradication of methane from low-concentration sources

AU - Krogsbøll, Morten

AU - Russell, Hugo S.

AU - Johnson, Matthew S.

N1 - Funding Information: The PERMA project is a collaboration between the University of Copenhagen, Aarhus University, Ambient Carbon ApS, Arla Foods, and Skov A/S to develop and field test a MEPS prototype. We thank these partners for their contributions to the PERMA project. We also thank NextGenerationEU and Innovation Fund Denmark for their Innomissions funding of the PERMA project under AgriFoodTure, and we thank AgriFoodTure for their administration in conjunction with the PERMA project. We would like to thank Bjørk Jakobsen for her help with methane measurements and Maarten van Herpen for helpful comments. We thank Ambient Carbon’s David S Miller and Laura LaCava for support and project management in conjunction with the research described in this article. Publisher Copyright: © 2023 The Author(s). Published by IOP Publishing Ltd.

PY - 2024

Y1 - 2024

N2 - Despite the urgent need, very few methods are able to efficiently remove methane from waste air with low cost and energy per unit volume, especially at the low concentrations found in emissions from e.g. wastewater treatment, livestock production, biogas production and mine ventilation. We present the first results of a novel method based on using chlorine atoms in the gas phase, thereby achieving high efficiency. A laboratory prototype of the methane eradication photochemical system (MEPS) technology achieves 58% removal efficiency with a flow capacity of 30 l min−1; a reactor volume of 90 l; UV power input at 368 nm of 110 W; chlorine concentration of 99 ppm; and a methane concentration of 55 ppm; under these conditions the apparent quantum yield (AQY) ranged from 0.48% to 0.56% and the volumetric energy consumption ranged from 36 to 244 kJ m−3. The maximum achieved AQY with this system was 0.83%. A series of steps that can be taken to further improve performance are described. These metrics show that MEPS has the potential to be a viable method for eliminating low-concentration methane from waste air.

AB - Despite the urgent need, very few methods are able to efficiently remove methane from waste air with low cost and energy per unit volume, especially at the low concentrations found in emissions from e.g. wastewater treatment, livestock production, biogas production and mine ventilation. We present the first results of a novel method based on using chlorine atoms in the gas phase, thereby achieving high efficiency. A laboratory prototype of the methane eradication photochemical system (MEPS) technology achieves 58% removal efficiency with a flow capacity of 30 l min−1; a reactor volume of 90 l; UV power input at 368 nm of 110 W; chlorine concentration of 99 ppm; and a methane concentration of 55 ppm; under these conditions the apparent quantum yield (AQY) ranged from 0.48% to 0.56% and the volumetric energy consumption ranged from 36 to 244 kJ m−3. The maximum achieved AQY with this system was 0.83%. A series of steps that can be taken to further improve performance are described. These metrics show that MEPS has the potential to be a viable method for eliminating low-concentration methane from waste air.

KW - agricultural methane emissions

KW - chlorine radicals

KW - gas phase oxidation

KW - methane control

KW - methane removal

KW - photoactivation

U2 - 10.1088/1748-9326/ad0e33

DO - 10.1088/1748-9326/ad0e33

M3 - Letter

AN - SCOPUS:85180549348

VL - 19

JO - Environmental Research Letters

JF - Environmental Research Letters

SN - 1748-9326

IS - 1

M1 - 014017

ER -