New technological developments in processing solid waste to energy

The state-of-the-art in production of energy from municipal solid waste outlining relative advantages, limitations, and economics of various systems is briefly reviewed including mass-burning versus RDF in spreader-stoker fired boilers; suspension-firing of RDF; pulverized fuel; pelletized fuels; and gaseous fuels generated by pyrolysis processes. A new system for processing solid waste for resource recovery separates the incoming waste by air-classification as the first processing step; conventional systems shred as the first processing step. This new system, originally developed to guard against shredder explosions, has the following supplemental advantages: produces a refuse-derived fuel (RDF) having higher heating values and less ash than conventional systems; and reclaims waste paper which can be used as paper-making furnish, utilizing current beneficiating and cleaning techniques. Production of paper from virgin materials requires 20 to 30 million Btu per ton of paper - versus 10 million Btu when waste paper is utilized as furnish. A new system proposed for storage, handling, and feeding refuse-derived fuel to large suspension-fired boilers is examined. This system proposes coarse shredding only of the light fraction at the solid waste processing plant; shipment in compactor trailers; storage in the same trailers; fine-shredding near the boiler; and air transport from the shreddersmore » using material handling fans injecting directly into the boilers. This system provides more efficient operation at less capital cost than systems utilized to date.« less