農産物(고구마)건조(乾燥) 및 건조시설(乾燥施設)에 관(關)한 시험연구(試驗硏究) (I) = “A study on Drying Characteristics and its Efficient Drying Facilities of Sweet Potato”（I )

다국어 초록 (Multilingual Abstract)

1. The output of sweet potato has increased so rapidely a few recent years,and this requires improved storing methods for utilizing as a raw material of alcohol and starch from sweet potato through year around. It has studied about drying of sweet potato by using drying facilities in this research.
2. In order to obtain the fundamental data of drying facilities using heated air, it has fullfilled the fundamental experiment of the model test and found out drying characteristics of sweet potato.
3. The curve of Equilibrium Moisture Content by temperature and relative humidity and the graph of drying period to dry to 12% (wet basis) final moisture content by variable drying conditions have obtained. And effect of air velocity and the sweet potato species has also studied in this research.
4. In Tunnel type dryer model test, it has been investigated of each drying status by temperature, air velocity, drying period, method of heated air supplying and tunnel length.
5. In Semi-Tunnel type dryer model test, the experiment about drying period, temperature, location of exhausting duct, effect of shutter, shape of heated air inlet, and operation method has studied.
6. In Band dryer model test, the experiment about drying period, material loading amount, recirculation, and reformation effect has done and the material shape was shredding in this experiment.
7. The result of Tunnel type model test has shown that moderate drying temperature is 90℃ to 100℃, drying period is about 4 hours, thickness of sweet potato is 3 to 5 mm, and the tray interval is 2 inches. The longer the length of tunnel is the more increase of thermal efficiency, however the drying status of short tunnel was better than the longer one. The drying of sweet potato shredding shows more rapid drying rate but it was not so great on drying.
8. The Semi-Tunnel type dryer is convenient to bult in limited area and easy to recirculate heated air through tunnel. It has also some benifits to be utilized this facilities as marine produts drying.
9. Sweet potato shredding was used as material sample in Band type dryer test. From the result of this experiment, it has known that the moderate material loading amount is 300g, the drying period is 90 minutes, temperature is 90°C to 100°C. It has very convenient procedure in drying process than Tunnel type dryer, and also decreased drying period. And thermal efficiency is increased by recirculation of heated air. This type of dryer has some benefits to be utilized as cocoon dryer.