Elemental balance of SRF production process: solid recovered fuel produced from municipal solid waste

Abstract

In the production of solid recovered fuel (SRF), certain waste components have excessive influence on the quality of product. The proportion of rubber, plastic (hard) and certain textiles was found to be critical as to the elemental quality of SRF. The mass flow of rubber, plastic (hard) and textiles (to certain extent, especially synthetic textile) components from input waste stream into the output streams of SRF production was found to play the decisive role in defining the elemental quality of SRF. This paper presents the mass flow of polluting and potentially toxic elements (PTEs) in SRF production. The SRF was produced from municipal solid waste (MSW) through mechanical treatment (MT). The results showed that of the total input chlorine content to process, 55% was found in the SRF and 30% in reject material. Of the total input arsenic content, 30% was found in the SRF and 45% in fine fraction. In case of cadmium, lead and mercury, of their total input content to the process, 62%, 38% and 30%, respectively, was found in the SRF. Among the components of MSW, rubber material was identified as potential source of chlorine, containing 8.0 wt.% of chlorine. Plastic (hard) and textile components contained 1.6 and 1.1. wt.% of chlorine, respectively. Plastic (hard) contained higher lead and cadmium content compared with other waste components, i.e. 500 mg kg(-1) and 9.0 mg kg(-1), respectively.

Challenges and Opportunities for Energy Recovery From Municipal Solid Waste in the Russian Federation

“…The results are presented in STAN 2.5.1302 and Sankey diagrams. The chlorine and mercury elemental balance was calculated based on dry weight concentrations of these substances in individual components [7], [21], [22] and the composition of each flow.…”

“…The elemental balance for chlorine and mercury in original MSW flow was calculated with respect to the chlorine and mercury content of individual components, the component composition of individual flows and the mass fraction of each output (Fig. 4) [7], [21], [22].…”

“…Food waste and PVC components contribute most to fines from the sorting process, where the concentration of food waste with insignificant chlorine is high, while the presence of PVC with high chlorine is low. Chlorine content in food waste can be accounted for by the presence of salt in food [7].…”

“…Mercury concentrates mainly in sorting residues and accounts for approximately 55%; the greatest contribution is made by textiles and ferrous metals [7], [22]. In the flow of secondary materials, the bulk of mercury content comes from metals (total contribution to secondary raw materials is about 78%).…”

“…European countries mainly produce solid fuels from waste by mechanical or mechanicalbiological treatment; in this case different processes for waste treatment are used [3]. Papers [4]- [7] analyze incoming and outgoing flows in the production of refused derived fuel (RDF) and determine their material, energy and elemental balances.…”