Design, quality, and quality assurance of solid recovered fuels for the substitution of fossil feedstock in the cement industry

Abstract

This paper describes the requirements for the production, quality, and quality assurance of solid recovered fuels (SRF) that are increasingly used in the cement industry. Different aspects have to be considered before using SRF as an alternative fuel. Here, a study on the quality of SRF used in the cement industry is presented. This overview is completed by an investigation of type and properties of input materials used at waste splitting and SRF production plants in Austria. As a simplified classification, SRF can be divided into two classes: a fine, high-calorific SRF for the main burner, or coarser SRF material with low calorific value for secondary firing systems, such as precombustion chambers or similar systems. In the present study, SRFs coming from various sources that fall under these two different waste fuel classes are discussed. Both SRFs are actually fired in the grey clinker kiln of the Holcim (Slovensko) plant in Rohožnik (Slovakia). The fine premium-quality material is used in the main burner and the coarse regular-quality material is fed to a FLS Hotdisc combustion device. In general, the alternative fuels are used instead of their substituted fossil fuels. For this, chemical compositions and other properties of SRF were compared to hard coal as one of the most common conventional fuels in Europe. This approach allows to compare the heavy metal input from traditional and alternative fuels and to comment on the legal requirements on SRF that, at the moment, are under development in Europe.

Production and Characterisation of SRF Premium Quality From Municipal and Commercial Solid Non-Hazardous Wastes in Austria, Croatia, Slovenia and Slovakia

“…In regard to the papers from Sarc et al (2014Sarc et al ( , 2019, where the requirements for production, quality and quality assurance of solid recovered fuels (SRF) used in Austrian cement industry were presented, this paper expands the scope of investigation, besides on Austrian cement industry, also on Croatian, Slovakian and Slovenian cement plants. Selected information on Mechanical-Biological Waste Treatment (MBT) Plants and co-incineration in cement industry in Croatia have been given in Sarc et al (2018).…”

“…legal, material, plant, and economic) to become a fuel supplier for the co-incineration sector. Individual developments and properties of SRF are extensively discussed in Beckmann et al (2012), Pomberger and Sarc (2012), Sarc and Lorber (2013) and Sarc et al (2014Sarc et al ( , 2019.…”

Sink–float density separation of post-consumer plastics for feedstock recycling

“…through co-incineration in cement kilns or through waste incineration employing fluidised bed technology. The polyolefin-rich LF (desired PO content > 90 wt%; hereinafter referred to as PO flakes) may be used as input material for feedstock recycling in thermochemical conversion units (for more detailed information on the composition of the input see [23] and for more detailed information on the analytical parameter of HF and MF see [16]). As illustrated in Fig.…”

Imaging of Flames in Cement Kilns To Study the Influence of Different Fuel Types

“…1 The manufacture of cement is a very energy intensive process and traditionally about 30 % of the production cost is related to fuels. 2 Alternative fuels are significantly cheaper than conventional fossil fuels giving cement producers an opportunity to reduce their operating costs.…”