Process concepts and techno‑economic analysis for multi-greenhouse gas mitigation of methane, nitrous oxide, and carbon dioxide
Time: Mon 2026-03-09 13.00
Location: Kollegiesalen, Brinellvägen 8, Stockholm
Video link: https://kth-se.zoom.us/j/62434669695
Language: English
Subject area: Chemical Engineering
Doctoral student: PhD Student Devesh Sathya Sri Sairam Sirigina , Energiprocesser
Opponent: Associate Professor Bjørn Austbø, Norwegian University of Science and Technology, Norge
Supervisor: Universitetslektor Shareq Mohd Nazir, Energiprocesser; Professor Stefan Grönkvist, Energiprocesser
QC 20260211
Embargo t.o.m. 2027-03-09 godkänt av skolchef Amelie Eriksson Karlström via e-post 2026-02-10.
Abstract
Mitigating climate change requires a diverse set of measures to reduce greenhouse gas (GHG) emissions. While the literature on carbon dioxide (CO2) abatement measures is extensive, research on the mitigation of non-CO2 GHGs is relatively limited. In particular, abatement measures for the residual emissions of methane (CH4) and nitrous oxide (N2O) from their largest source – agriculture – have not been adequately discussed. This thesis proposes process concepts to mitigate CH4 and N2O through catalytic conversion. These concepts were extended to include CO2 capture, and the integrated configurations were evaluated for different emission conditions. Multi-GHG mitigation of CH4, N2O, and CO2 can thereby be applied to abate the residual GHG emissions.
Two process routes based on thermal and photocatalysts were developed for CH4 mitigation. Techno-economic assessment results show that the CH4 mitigation costs in both routes are strongly dependent on inlet concentrations. Electricity and catalyst were the main cost drivers in the thermal catalytic route, while reactors have the highest cost share in the photocatalytic route. The costs can be lowered by using the catalysts that are inert to moisture.
Mitigation costs for multi-GHG mitigation are sensitive to the order of GHG mitigated in the integrated unit. The costs were lower when CO2 is mitigated first, followed by N2O and CH4. Catalysts that decompose N2O at low temperatures (< 300 °C) and are inert to other gases in the inlet stream can bring down costs in multi-GHG mitigation. These processes must be tested under field conditions to check interactions with other gases. Using renewable electricity is crucial to improve the climate effectiveness of the technology.
CH4 mitigation from agriculture promotes sustainable development goals. However, adequate policies measures are required, especially in developing countries, to support large scale deployment of these measures.