본 연구는 열풍 건조장치를 이용하여 음식물류 폐기물의 재활용 측면에서 음식물류 폐기물과 열풍 (200℃, 250℃) 건조방식에 따른 운전시간별 건조특성을 평가하고자 하며, 또한 건조물질의 삼성분 (수분, 가연분, 회분) 등 고형연료로서의 품질특성을 평가하는데 그 목적이 있다.
본 연구에 사용된 음식물류 폐기물은 B시 P사에서 채취하여 사용하였으며, 음식물류 폐기물과 가연성 물질의 균질 혼합 및 건조효율 향상을 위하여 비닐, 어패류 등 이물질을 제거하였다. 열풍 건조장치의 전체 크기는 W 1,360 mm × L 1,060 mm × H 900 mm, 열풍 건조장치의 조사강도는 1 kW이며, 건조온도는 최대 300℃까지 조절할 수 있도록 제작하였다.
음식물류 폐기물 건조실험을 실시한 결과 열풍 (200, 250℃) 건조를 이용한 완전건조 (함수율 10% 이하)시 최종 함수율 변화는 운전시간 각각 30분에서 8.5%, 25분에서 8.9%로 나타났다.
실험결과 음식물류 폐기물에 첨가물을 혼합하였을 경우, 음식물류 폐기물의 재활용 방안으로 열풍 융합건조공정을 이용한 고형연료의 생산이 충분히 가능할 것으로 판단된다.The main objective of this study is on the development of a method for recycling food waste by using the inner-cycle Thermal air (200, 250℃) drying process, aiming to assess the quality of RDF(refuse derived fuel) in terms of its 3-component analysis (water content, ash content and combustible content).
The food waste used in this research was collected at P Company located in B City. For homogeneous mixture of food waste with combustible materials and for better drying efficiency, foreign substances which were vinyl, fish and shellfish were removed. The size of the inner-cycle thermal air drying unit is 1,360 mm(W) × 1,060 mm(L) × 900 mm(H), and its projection intensity and frequency were 1 kW and 2,450 MHz, respectively. Also, unit was designed to control the drying temperature up to 300℃.
As a result of the experiment, the food waste dried using the inner-cycle Thermal air (200, 250℃) drying process led to the final moisture contents of 8.5%, 8.9%, respectively, which levels were lowest for full harness (moisture content : less than 10%) and 30, 25min operating period. The result of an experiment, food waste was found to produce good quality RDF that met the quality standard. In sum, as a way for recycling food waste, the inner-cycle Thermal air drying process seems capable of producing RDF to the full extent.