Pyrolysis of waste milk packets in a screw-type continuous reactor: Optimization through response surface methodology and products characterization

In this work, the pyrolysis of waste milk packets was conducted in a screw-type continuous reactor. The waste milk packets were characterized by the proximate, ultimate, and thermal analyses. The central composite rotatable design has been applied with the variation of reaction temperature and residence time to investigate the optimum process conditions. In addition, different input-output models have been developed for predicting oil, gas, and char yield. The optimum process temperature and residence time were identified to be 477 degrees C and 45 min, respectively. The yield of oil, gas, and char at the optimum conditions achieved were 51.19 wt%, 41.79 wt%, and 7.00 wt%, respectively. Ultimate composition, physical properties, heating value, and chemical composition analysis of oil have been performed. The composition of gaseous products has been analyzed. The physical properties of the oil were comparable to conventional fuels. The carbon range of the oil is C-5-C-16, which can be used as a transportation fuel.