Abstract: The organic components in municipal solid waste (MSW) can be classified into biogenic and fossil-derived fractions. Only carbon emissions from the combustion of fossil-derived components are accounted for in the carbon emissions from waste incineration. Online monitoring of carbon sources in complex waste streams is essential for accurately assessing the carbon emissions and reduction benefits of WtE incineration plants. Based on the characteristics of China’s waste incineration processes, an online monitoring method for the carbon sources of incinerated waste in WtE plants using energy-mass balance principles was developed. A case study was conducted at a WtE plant in Zhejiang province, where radiocarbon (14C) comparative experiments were carried out to validate the accuracy and sensitivity of the method under actual operating conditions. Furthermore, a systematic analysis was performed to quantify the carbon source composition and carbon emissions of the waste at the plant. The results indicated that for the No.2 incinerator (with a daily processing capacity of 750 tons) in 2023, the monthly average proportion of biogenic components in the waste exceeded that of fossil-derived components by 7.10-18.74 percentage points. The annual incineration of waste generated a total of 87.3 thousand tons of fossil-derived carbon emissions, with the fossil carbon emission factor (in terms of CO2) per ton of waste ranging from 277.55 kg/t to 421.56 kg/t. Additionally, the findings further demonstrated the limited applicability of default values in existing carbon emission methodologies. The online carbon source monitoring method established in this study provides a methodological foundation for carbon emission accounting and real-time monitoring in WtE incineration plants.

Key words: carbon emissions from municipal solid waste incineration, online monitoring for carbon source, energy and mass balance model, plausibility check, carbon emission factor