RDF production plants: I Design and costs

Abstract

Municipal solid waste (MSW) management calls for the integration of different recovery, recycling and disposal technologies. Among these possible options, MSW may be treated in order to obtain a fuel to be sold to third party users or directly utilized to generate electricity provided it is of sufficient quality to be employed instead of traditional fuels. In this two-part paper the problem of producing refuse derived fuel (RDF) having a high heating value (LHV>4000 kcal/kg) has been examined from a technical and economic viewpoint. In the first part article a technical assessment of production plants is carried out. Different production lines have been thus compared in terms of mass efficiency, heating value of produced RDF and treatment cost highlighting how the choice of process equipment affects the system performances. As a result the process plant configurations enabling to meet the required product specifications are identified. The influence of mixing a high calorific waste such as scrap tires with the stream of household waste, in the limits allowed by current regulation, has been also analyzed and found to be a prerequisite to meet the prescribed heating value target. Economic feasibility and financial risk of RDF production plants have been successively evaluated in the second part article over a capacity range of 25–200 t/h considering also integrated facilities including compost production and/or electricity generation. The analysis has been carried out with reference to the current Italian market scenario even if it has a general applicability and its relevance is wider geographically.