Pyro-gasification of Norwegian industrial solid waste (ISW) for hydrogen production and district heating application: A 4-E (energy, exergy, environment, and economic) analysis

Electricity or heat production from waste incineration is often inefficient and costly, posing challenges for Norway’s ambition to achieve net-zero carbon emissions and a hydrogen-based economy by 2050. To address these challenges, this study aims to develop and evaluate two advanced thermochemical pathways- Sorption-Enhanced Chemical Looping Gasification (SE-CLG) and Pyrolysis-Integrated SE-CLG (Pyro-SE-CLG) for tri-generation (hydrogen, heat, and electricity) from Norwegian Municipal Solid Waste (MSW) and Industrial Solid Waste (ISW), while improving waste management efficiency and environmental performance. Experimental characterization of typical Norwegian ISW (HHV = 17.43  MJ/kg; LHV = 16.22  MJ/kg) revealed substantial energy potential. From literature, heavy metal presence in this type of waste and oxygen carrier (OC) deactivation with ash interaction prompted the development of the Pyro-SE-CLG model to enhance feedstock flexibility, facilitate heavy metal removal, and align waste utilization with national decarbonization goals. Both models were simulated using Aspen Plus and assessed via a 4-E (Energy, Exergy, Environment, and Economic) analysis. The SE-CLG maximized hydrogen yield at (170.6  kg H2/ton MSW; 142.8  kg H2/ton ISW), energy efficiency (up to 69.11 %), exergy efficiency (up to 57.29 %), and hot water recovery (up to 4,300 L/ton MSW) for district heating applications. Pyro-SE-CLG, while yielding 16–20 % less hydrogen and requiring five times more oxygen carrier (OC), enabled complete heavy metal removal using 200  kg of 1  M HCl per ton ISW and improved OC reusability, thereby reducing operational costs. Sensitivity analysis identified optimal hydrogen production at 800 °C (fuel reactor) and 200 °C (WGSR), with Ca2Fe2O5 ensuring stable performance across both configurations. Environmental analysis highlighted SE-CLG(MSW) as the most favorable option, achieving 25.55 % lower global warming potential (GWP) and 66.80 % lower acidification potential (AP) than ISW, while Pyro-SE-CLG reduced GWP during pyrolysis but exhibited higher post-PSA emissions due to lower CO2 capture efficiency. Economically, Pyro-SE-CLG(ISW) achieved the lowest hydrogen sale price (3.32 USD/kg), whereas SE-CLG(ISW) recorded the highest sustainability index (SI = 2.34). By optimizing hydrogen and heat recovery while addressing heavy metal contamination, this study supports Norway’s transition toward a circular, low-carbon energy system and demonstrates the potential of waste-to-hydrogen pathways to meet national 2050 sustainability targets.