Waste-to-X: An enviro-economic assessment of circular chemical production via municipal solid waste gasification

As the generation of municipal solid waste continues to increase, its inadequate disposal is becoming a meaningful threat to the health of both humanity and the planet. Most waste is either landfilled or incinerated, which exacerbates climate change, incidence of respiratory diseases, and damage to marine environments. As the chemical industry moves towards a circular economy model, the gasification of municipal solid waste has garnered increased attention as it offers both an alternative waste management solution and the exploitation of an abundant renewable feedstock. In this work, three distinct municipal solid waste gasification pathways are investigated, with each leading to different chemical products. The routes considered are: i) methanol synthesis; ii) methanol-to-olefins; and iii) ethanol synthesis via dimethyl ether hydrocarbonylation. The results suggest that whilst the methanol route was competitive with the incineration base case in 2017-18 due to elevated methanol prices, all three routes would require higher gate fees on average (up to 3 times higher) to break-even across 2017-22 market conditions. The ethanol route displays the lowest required gate fees on average due to a lower H2 requirement and lower capital costs. However, all routes achieve a 40-80% reduction in scope 1 and 2 CO2 emissions when compared to incineration.