Journal of Microwave Power and Electromagnetic Energy (JMPEE)
TITLE	Thermal Processing of Food Packaging Waste Using Microwave Heating [PDF]
AUTHORS	J. Casasnovas and R.C. Anantheswaran 1994 29 3 171-179
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Abstract A method for thermal processing of food packaging waste using microwaves was developed. The waste material was shredded and compacted into cylinders with added moisture. The cylinders at different densities and moisture contents were processed at three microwave power levels, and at 0 and 15 psig over pressure. Heating rate decreased with density. At 2.83x10^-2 W/cm^3 absorbed power, locations close to the surface of the material had slower heating rates. At low densities (1.004 g/cm^3 to 2.510 g/cm^3 ), heating rate was higher at 40% moisture content than at 35 and 50% moisture contents. At higher densities (3.012 g/cm^3 to 4.016 g/cm^3 ) heating rates were higher at 35 and 50% moisture contents. At 4.48x10^-2 W/cm^3 and 5.85x10^-2 W/cm^3 absorbed power, heating rate increased with power and was not significantly higher at any specific location. Uniform temperatures of 121°C were attained when the waste samples were heated in an enclosed chamber at 4.48x10^-2 W/cm^3 absorbed power and 15 psig steam over pressure. Logarithmic reductions from 0.4 to 1.3 of B. stearothermophilus (test organism) were observed when the sample was heated for process times ranging from 60 to 101 seconds, compared with predicted values of 1.1 to 3.3 based on the time-temperature data. Key Words: Microwave sterilization, Solid waste disposal.