Promoting carbon neutrality through the optimal allocation of waste for energy utilization

Abstract

Pathways toward carbon neutrality (CN) in industrial and waste sectors by optimizing energy use according to heat demand temperature levels are examined. While low-temperature heat below 100 ℃ can be efficiently supplied using heat pumps powered by renewable electricity, high-temperature industrial processes such as steam production and cement kilns remain difficult to decarbonize solely through electrification due to cost and supply stability challenges.

The study emphasizes the importance of allocating waste and biomass resources based on their calorific characteristics to appropriate thermal applications. In particular, direct steam generation from low-grade, non-recyclable waste (Waste to Steam) is shown to significantly improve energy efficiency and fossil fuel substitution compared with conventional waste-to-power systems.

Furthermore, the Life Cycle Carbon Neutral (LCCN) concept is explained, integrating efficient thermal utilization of waste with carbon capture and utilization (CCU) to convert incineration-derived CO2 into chemical feedstocks. A semi-quantitative comparison with chemical recycling routes indicates that LCCN can achieve greater carbon reduction and economic advantages, especially for low-quality waste streams.

Overall, combining thermodynamically optimal heat use with CCU provides an effective transition strategy for near-term emission reductions and long-term CN achievement.