In Korea, the daily waste production in 2015(excluding specified waste) was 404,812 tons, of which household waste accounted for 12.7%(51,247 tons/day). Total household food and vegetable waste amounted to 1,120 tons/day; of this, 70% of was ultimately used as feed or fertilizer and 30% was buried. In this study, a drying unit was developed to enable the production of solid refuse fuel using high-moisture food waste, and its performance was examined through an experiment. Thus, a laboratory pyrolysis system with a drying capacity of 500 kg/hr was manufactured. Food wastes were collected from a company cafeteria and from Changwon City and used for experiment. The drying characteristics of the food waste were examined depending on the input temperature of the drying air. The results of the food waste drying experiment showed that the total required drying time was approximately 20 hours, and the drying speed was approximately 2.90 %/hr. The drying time was five hours longer than the research target value(15 hours per batch). However, the time was approximately 16 hours when the preheating and cooling times required for the input and output were excluded, which was close to the research target value. The drying time did not show a large difference depending on the temperature of the input drying air. Drying time was 21 hours at 155℃, and thus drying operation would be possible without the use of high-temperature air(more than 200℃) when waste heat is utilized in the future. It is thought that rather than the temperature of the input air, it is the contact area between the input air and the food waste that has a significant effect on reducing the drying time.

ABSTRACT
 Introduction
 Materials and Methods
  1 Analysis of the heat flow within the drying unit
   1.1 Analysis method
   1.2 Model establishment
   1.3 Model analysis
  2 Analysis of the drying characteristics
   2.1 Experiment device
   2.2 Experiment material
   2.3 Experiment method
 Results and Discussion
  1 Analysis of heat flow within the drying unit
   1.1 Model verification
   1.2 Flow velocity and temperature distribution
  2 Analysis of the drying characteristics
 Acknowledgement
 References

• Dae-Hong Jung(NDT Engineering Co., Ltd.)
• Jong-Hyun Yoon(NDT Engineering Co., Ltd.)
• Sung-Min Choi(NDT Engineering Co., Ltd.)
• Ki-Hyeon Lim(NDT Engineering Co., Ltd.)
• Dae-Bin Song(Dept. of Bio-Industrial Machinery Eng., Gyeongsang National Univ.(Institute of Agric. & Life Sci.)) Corresponding author