In this work, an experimental study was done in an autoclave reactor to evaluate the gasification characteristics of food waste in supercritical water. The effects of reaction temperature (550–700 °C), residence time (0–30 min), feedstock concentration (5 wt%-9 wt.%), catalyst type (K₂CO₃, Na₂CO₃, and Raney-Ni), and catalyst loading (Catalyst/dry feedstock 0.5–2) on gas production and liquid products were investigated. The results indicated that higher reaction temperature and longer residence time positively promoted food waste gasification. The organic compound species in liquid products decreased quickly to form gas products with the increased temperature, and the aromatic compounds were the key organic matter for the complete gasification of food waste. The addition of catalysts could significantly convert more liquid intermediates into gaseous products, and improve the gasification performance of food waste. The catalytic performance of catalysts can be ranked as K₂CO₃> Raney-Ni > Na₂CO₃. H₂ yield and carbon gasification efficiency increased with the increase of K₂CO₃ loading, reaching the highest values of 38.29 mol kg⁻¹ and 95.84% with the addition of 14 wt% K₂CO₃, respectively. This work indicated that food waste could be well treated and utilized as an energy resource to produce H₂ by SCWG technology.

Role-playing simulations have gained in popularity in recent years as a novel method of engaging researchers and stakeholders in a variety of social and environmental issues. While academic interest has grown on this topic, knowledge remains sparse on the underlying theories that may guide the design of such games. Thsi article introduces a new game design framework - Com­pleC­Sus (Com­plex­ity-Col­lab­o­ra­tion-Sus­tain­abil­ity) - built on the concepts of social learning and procedural rhetoric. We describe and discuss the conceptual basis for our framework, giving a detailed account of its application through the recently developed the Water–Food–Energy Nexus Game (Nexus Game) as an example. We illustrate the process involved in designing the Nexus Game through initial scoping, prototyping, and design decisions, and how game structure and debriefing have been crafted to foster social learning focused on the understanding of the underlying social-ecological system as well as fostering collaboration between stakeholders. We also provide the analysis of qualitative data collected during recent gaming sessions across three continents to evaluate the Nexus Game’s potential learning effects.