Acceleration Process of Food Waste Treatment and Higher Quality Product with Innovative Rotary Kiln Composter

The objective of this research is to utilize a rotary kiln composter to rapidly process food waste into mature and stable compost without the production of leachate. This research also ensures that the compost generated fulfil to the quality standards established by SNI 19-7030-2004. Furthermore, the operation of the rotary kiln composter can be assisted by using a smartphone, which simplifies the operation. Food waste was chopped and placed into a rotary kiln composter equipped with an aeration system (6 L/min), stirring mechanism, and remote-control functionality via mobile phone for automated operation. Further, a bulking agent was added with a ratio of food waste vs bulking agent of 70:30. The addition of microorganism mass was varied to speed up the composting process for 14 days. The results showed that the compost derived from food waste was stable within 3 days. The temperature of the food waste matrix reached 46 °C, and the pH value of the compost was close to neutral since day 4. In this study, no leachate was produced, either R1, R2, R3, or R4. The final total organic carbon (TOC) content was 12.12–15.22%, Total-N was 0.83–1.04%, phosphorus was 0.18%, and potassium was 1.05%. On the basis of the C / N value and the germination index (GI), the R2, R3, and R4 reactors produced mature and stable compost on the third day with C/N values < 20 and GI > 100%. This result is a good breakthrough because the rotary kiln composter can accelerate the composting process of food waste within 3 days.