PRODUCING SOLID FUEL FROM NON-RECYCLABLE AGRICULTURAL PLASTICS

A plastic-derived fuel production process was developed and has been shown to be effective for non-recyclable plastics that are widely used in agriculture and normally discarded. A machine was designed, constructed, and evaluated with regard to energy balance and fuel nugget production. The hydraulically driven machine processed dirty, non-recyclable plastics by first compacting and then extruding them through four internal channels of a heated die. The process produced plastic fuel nuggets with a thin, melted exterior which trapped unnzelted plastic in the interior: The Plastofuel (TM) nuggets were 3.8 cm (1.5 in.) wide, 3.8 cm (1.5 in.) high, and were cut to a length of 5.1 cm (2 in.). All aspects of machine operation, with the exception of feedstock loading, were automated and controlled by an onboard microprocessor The machine was equipped with two data loggers to collect hydraulic and electric system energy metrics. Component positions, electric power consumption, and hydraulic system pressure were recorded and converted to total energy consumption for all production runs. Energy content of the Plastofuel (TM) formed using clean household plastic and unused mulch film was 45.5 MJ/kg (19500 Btu/lb). Plastofuel (TM), formed with dirty, used mulch film and used plastic pots and trays, had an energy content of 38.8 MJIkg (16700 Btu/lb). A system energy ratio was determined by dividing the combined hydraulic and electric energy used for Plastofitel formation into the potential energy stored in all plastic nuggets formed for a single lest run. The highest energy ratio (E(out)/E(in)) from all test runs was 47. The maximum Plastofuel ' production rate achieved with the machine was 27.6 kglh (61 lb/h).