The Study of Temperature Management of Reefer Container in Low Temperature Logistics System

低溫物流系統冷凍貨櫃溫度管理之研究

為尋找防止冷凍貨物鮮度不佳及貨損的最適物流條件，本文首先比較不同凍結溫度對鯖鰺預冷貯存之影響，鯖鰺貨物分別置於以-25℃預冷及-20℃預冷之凍結設備，實施急速冷凍，並定時測定其溫度。結果顯示，以-25℃送風式凍結法於凍結17小時，貨物中心溫度可以到達-19℃，而以-20℃送風式凍結法中心溫度為-15.1℃，而並無顯著的下降，距離指定運送溫度有3.9℃之溫差。當貨物表面溫度到達-19℃所須之時間，-20℃送風式凍結法為7 小時、-25℃送風式凍結法為5 小時。其次，比較不同積載方式對鯖鰺貨物之影響，鯖鰺貨物分別以水平積載、垂直積載及超高積載方式置於以-19℃之冷凍模擬櫃，實施急速冷凍，並定時測溫。結果顯示，水平、垂直積載櫃內溫差沒有超過3℃，而超高積載方式則有超過3℃。接著，比較不同斷電期間對鯖鰺鮮度之影響，短期間斷電以蘇澳運送至基隆時間2 至3 小時，對冷凍鯖鰺影響有限，但人為因素延遲交櫃，而造成較長期間如隔日交櫃而斷電18 小時以上，對冷凍鯖鰺貨物就有影響。結果顯示，以運送協議許可斷電8 小時，貨物表面溫度上升至-15.6℃左右，中心溫度為-16.1℃，而櫃溫上升至-14.6℃。如以斷電18小時，貨物表面溫度上升至-11.8℃左右，中心溫度為-12.5℃，櫃內溫度為-9.5℃。

To preserve freshness and to prevent damage of frozen cargo, the condition on logistical process is optimized. The effects of -25°C air blast and -20°C air blast freezing methods on the pre-cooling stowage of mackerel and scad are also investigated. After 17 hours of freezing by -25°C air blast, the temperature of the frozen products reaches -19°C, whereas by -20°C air blast, the temperature of the products reaches -15.1°C (a 3.9°C temperature difference from the required transportation temperature). The effects of horizontal, vertical, and over load stowage on mackerel and scad are also studied. After freezing by -19°C air blast, the temperature difference between horizontal and vertical stowage is < 3°C, and the temperature difference for over load stowage is > 3°C. After eight hours of no power in the reefer container, the surface body temperature of the fish rises to -15.6°C and central body temperature to -16.1°C; after 18 hours of no power, surface body temperature rises to -11.8°C and central body temperature to -12.5°C with container temperature reaching -9.5°C.