Optimizing Co-Firing Ratio of RDF MSW and Coal in a Fluidized Bed Reactor

Abstract:

Co-firing Refuse Derived Fuel (RDF) from Municipal Solid Waste (MSW) with coal presents a promising approach to urban waste management and reduction of fossil fuel dependency. This study primarily investigates the optimal co-firing ratio of RDF MSW and coal, alongside other operational parameters, in a laboratory-scale fluidized bed reactor. Experiments were conducted with variations in RDF MSW to coal ratio (5%, 10%, 15%), operating temperature (750°C, 850°C, 950°C), and excess air (15%, 20%, 25%, 30%) in a reactor with a combustion chamber volume of 1000 cm³. Results demonstrate that the co-firing ratio significantly influences combustion efficiency and overall performance. The optimal ratio was found to be 10% RDF MSW with 90% coal, yielding a peak combustion efficiency of 95.89% and a minimum Specific Fuel Consumption (SFC) of 0.19260 kg/kWh. This optimal ratio balances the benefits of RDF's higher volatile content with coal's stable combustion characteristics. Additionally, an operating temperature of 750°C and excess air of 20% complemented this optimal ratio, further enhancing stability and efficiency. SEM analysis and chemical composition studies of agglomerates revealed the role of Ca, K, Na, and Mg in deposit formation, providing insights into the interaction between RDF and coal during co-firing. This research offers valuable guidance for optimizing co-firing ratios in industrial applications, supporting the development of more efficient and environmentally friendly waste-to-energy solutions.

• Periodical: Engineering Chemistry (Volume 13)
• Pages: 83-92
• DOI: https://doi.org/10.4028/p-tHuQM5
• Online since: February 2026
• Authors: I Made Agus Putrawan*, I Nyoman Suprapta Winaya, I Nengah Simpen, Ida Bagus Alit Swamardika, I Made Rajendra, Wayan Gede Ariastina, I Putu Angga Yuda Pratama, I Gusti Ngurah Putu Tenaya
• Keywords: CoAl, Co-Firing Ratio, Combustion Efficiency, Fluidized Bed, MSW, RDF, Waste-To-Energy

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DOI: 10.3390/en15165785