Search

The proposal of the dual carbon goal and the blue economy in China has sparked a keen interest in carbon emissions reduction from sewage treatment. Carbon accounting in urban sewage plants serves as the foundation for carbon emission reduction in sewage treatment. This paper re-evaluated carbon accounting in the operational processes for urban sewage treatment plants to develop a novel carbon emission evaluation model for anaerobic-anoxic-oxic treatment plants. The results show that the carbon emissions generated by non-carbon dioxide gases far exceed the carbon emissions from carbon dioxide alone. Moreover, the recycling of sewage leads to carbon emissions reduction that offsets the carbon emissions generated during the operation of the sewage plant. Also, the carbon emissions generated by sewage treatment plants are lower than those generated by untreated sewage. The findings and insights provided in this paper provide valuable references for carbon accounting and the implementation of low-carbon practices in urban sewage treatment plants. [Display omitted] • A novel carbon emission evaluation model for AAO treatment plants was proposed. • Mechanical processes generated higher carbon emissions than energy and chemicals. • The determination of direct and indirect emissions of CO 2 from sewage plants. • Sewage recycling can offset carbon emissions from the operation of sewage plants. [ABSTRACT FROM AUTHOR]

Significant climate finance gaps exist for small islands in transitioning to net zero, as climate commitments far outweigh the government budget and international financing. To create alignment between resource allocation and climate commitments, a roadmap for strategic and cost-effective decarbonization is of supreme importance. This paper presents a geographic carbon accounting model which incorporates emissions from electricity, transportation, food systems, and human respiration, whilst accounting for the carbon uptake by the terrestrial biosphere in view of identifying high-intensity aggregated emissions estimated in the range of 200–215 ktCO 2e in the coastal and inland urban regions of the remote island of Mauritius. An estimated 4641 ktCO 2e , representing 79.4% of overall emissions, has been observed to originate from buildings, food, and waste systems. About 1150 ktCO 2e , accounting for a share of 19.7%, is derived from transport systems. The study advocates for the enhanced participation of local authorities to better contribute to climate governance, whilst supporting legislative, financial, technological, and behavioural reforms. Despite the relatively low sequestration potential of forests replacing all non-habitable lands, which is estimated at 1002 ktCO 2e and representing about 17.1% of annual net emissions, afforestation programmes are encouraged owing to multiple ecosystem services provided by trees. • A GIS-based Carbon Accounting framework is developed for a remote island. • High-intensity emission hotspots are identified for strategic management responses. • Enhanced participation of local authorities in climate governance is encouraged. • Legislative, financial, technological, and behavioural reforms are proposed. [ABSTRACT FROM AUTHOR]