Effect of Waste-Derived Fuels (SRF/RDF) Composition on the Cement Industry’s Environmental Footprint

Abstract Solid recovered fuels (SRF) can be effectively produced in a Sustainable Municipal Solid Waste Treatment Plant (SMSWTP), after applying all the adequate R-processes. It was found that SRF can be used as an alternative solid fuel (ASF) in the cement production process, with substantial regulation of environmental emissions and economic benefits. The adequate replacement of conventional fossil fuels is a promising solution to reduce the environmental footprint of the cement industry. SRF classification in 5 categories, concerning the composition of pollutant generation compounds (e.g., Cl, Hg), tries to contribute toward its use as an ASF in cement kilns. This paper seeks to find a correlation between the SRF composition with the environmental impact of the cement industry. A thorough investigation of recently reported literature data, with emphasis on the ASF composition and the obtained cement kiln emissions, showed that their chlorine content is the main factor that aggravated the environmental impact of ASFs compared to conventional fuels. Chlorine is the crucial compound responsible for the generation of toxic and harmful pollutant compounds such as Polychlorinated Dibenzodioxins/Furans (PCDD/Fs). ASFs with low chlorine content ≤ 0.2 wt. %, classified as SRF of class 1, were considered in this study. These harmful emissions of a cement kiln are well correlated with the chlorine content of the ASF. Following the derived correlation, it is suggested that the use of ASFs with a chlorine content ≤ 0.078 wt. % can only lead to acceptable cement kiln emissions. The use of low-emission SRF in the cement industry can achieve the goal of the drastic reduction of landfill waste with no extra need in the construction of polluting waste combustion installations while fulfilling the zero-waste target. ASFs with a chlorine content ≤ 0.078 wt. %, particularly lower than that of the class 1 SRF (≤ 0.2 wt. %), must be used in the cement industry to meet the exhaust standards and improve its environmental footprint. Graphical Abstract Adequate preparation and use of SRF can result in sustainable Municipal Solid Waste Management towards almost zero waste to landfills.