A Comparative study of carbon footprints of LDPE plastic waste landfilling and valorization to gasoline for generator usage

The impact of greenhouse gas emissions from improper waste disposal is widespread and profound; affecting environment, economies, public health, and the global climate system. This study compared the carbon footprint associated with the conversion of plastic wastes into gasoline for fueling generator, and the carbon footprint for using unsanitary landfill to dispose of the plastic wastes. Pyrolysis fixed bed reactor was fabricated for the conversion of 10 kg of ground LDPE to 400 ml of liquid oil from which 213.33 ml of gasoline was obtained. The findings indicated that that usage of unsanitary landfill for the disposal of 1000 kg of LDPE plastic wastes led to the emission of 1,188 kg GHG per megajoule (MJ) while usage of pyrolysis process for the conversion of 1000 kg of plastic wastes to gasoline for generator usage resulted in the emission of 1,203.113 kg GHG/MJ. Both waste management techniques emitted a significant amount of greenhouse gases, with pyrolysis emitting a marginally higher amount. The higher emission from the pyrolysis process might be due to the ineffective design of air-fuel mixing port of the pyrolysis furnace, as well as, the usage of liquefied petroleum gas as fuel for the pyrolysis process. Further improvement on the design and process parameters could make the carbon footprint of using pyrolysis technique for plastic waste management to be drastically reduced, thereby, making the technique to be environmentally friendly and sustainable.