title: Solid recovered fuel: influence of waste stream composition and processing on chlorine content and fuel quality.
abstract: Solid recovered fuel (SRF) produced by mechanical-biological treatment (MBT) of municipal waste can replace fossil fuels, being a CO(2)-neutral, affordable, and alternative energy source. SRF application is limited by low confidence in quality. We present results for key SRF properties centered on the issue of chlorine content. A detailed investigation involved sampling, statistical analysis, reconstruction of composition, and modeling of SRF properties. The total chlorine median for a typical plant during summer operation was 0.69% w/w(d), with lower/upper 95% confidence intervals of 0.60% w/w(d) and 0.74% w/w(d) (class 3 of CEN Cl indicator). The average total chlorine can be simulated, using a reconciled SRF composition before shredding to <40 mm. The relative plastics vs paper mass ratios in particular result in an SRF with a 95% upper confidence limit for ash content marginally below the 20% w/w(d) deemed suitable for certain power plants; and a lower 95% confidence limit of net calorific value (NCV) at 14.5 MJ kg(ar)(-1). The data provide, for the first time, a high level of confidence on the effects of SRF composition on its chlorine content, illustrating interrelationships with other fuel properties. The findings presented here allow rational debate on achievable vs desirable MBT-derived SRF quality, informing the development of realistic SRF quality specifications, through modeling exercises, needed for effective thermal recovery.
authors.affiliation: Centre for Energy and Resource Technology, Department of Environmental Science and Technology, School of Applied Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
authors.forename: Costas
authors.initials: C
authors.lastname: Velis
authors.forename: Stuart
authors.initials: S
authors.lastname: Wagland
authors.forename: Phil
authors.initials: P
authors.lastname: Longhurst
authors.forename: Bryce
authors.initials: B
authors.lastname: Robson
authors.forename: Keith
authors.initials: K
authors.lastname: Sinfield
authors.forename: Stephen
authors.initials: S
authors.lastname: Wise
authors.forename: Simon
authors.initials: S
authors.lastname: Pollard
mesh_terms: D002713:Chlorine / Q000032:analysis*; D004736:Energy-Generating Resources / Q000592:standards*; D004787:Environmental Pollution / Q000517:prevention & control*; D008962:Models, Theoretical; D059027:Recycling / Q000379:methods*; D012037:Refuse Disposal / Q000379:methods*; D006113:United Kingdom; D014866:Waste Products / Q000032:analysis*
chemical_list: D014866:Waste Products; D002713:Chlorine