冷凍真空乾燥系統技術研製

Development of Vacuum Freeze-Drying System

許佳琪(Chia-Chi Hsu)

指導教授 ： 鄭鴻斌

國立臺北科技大學/機電學院/冷凍空調工程系所/碩士(2005年)

摘要

冷凍真空乾燥法是將欲乾燥物以急速凍結的方法先行固化，在適當的真空條件下使冰昇華為水蒸氣，以達到除去物品中水份的方法；冷凍真空乾燥法包含有低溫凍結、低溫低壓抽氣以及脫附過程三種程序，其低溫冷凍系統分為兩組，一組是供應給預凍使用，另一組是供應給冷凝器使用，主要是利用二元壓縮循環系統(Cascade system)，供應的最低溫度可達-85℃；而真空系統是利用乾式真空幫浦(Dry vacuum pump)進行抽氣，以達到無油氣污染的優點；脫附過程是利用一組循環水槽加熱系統，以提供棚板熱源來輔助產品達到快速乾燥的方法。本論文開發製藥與生物技術產業用之冷凍真空乾燥設備製程研究，以冷凍真空乾燥20%葡萄糖溶液與20%食鹽水溶液對其樣品進行真空乾燥，以初級乾燥中棚板溫度為20℃、10℃、0℃、-10℃與-20℃，探討在不同棚板溫度下對樣品溫度、壓力與乾燥程度之變化。從實驗得知當棚板溫度低，越接近樣品溫度，所得到的乾燥度越佳，外觀更完整，以棚板-20℃下20%葡萄糖溶液失水率可達88%，凍乾後呈現不規則孔洞狀；而20%食鹽水溶液失水率可達82%，外觀上以20%食鹽水溶液乾燥後外型較完整呈現鬆散塊狀。乾燥過程中架設低溫量測計與真空壓力計，分析凍乾樣品之抽氣過程，其壓力及溫度變化，並對乾燥後的產品進行包括凍結溫度、抽氣速率、終極壓力、產品的含水量等量測，此外利用微觀測系統以動態即時的方式觀測產品凍乾過程的形狀變化，確保產品的品質。

關鍵字

冷凍真空乾燥 ； 凍乾

並列摘要

Vacuum freeze-drying is by solidifying the dry object by means of rapid freezing, then sublime the ice into water vapor under appropriate vacuum conditions to eliminate the water content in the object. Vacuum freeze-drying includes three procedures, namely lyophilization, low-temperature low-pressure air extraction, and desorption process. The low-temperature freezing system includes two parts, one is for pre-freezing, and another is for condenser. It mainly uses Cascade system to supply low temperature down to -85℃. The vacuum system uses dry vacuum pump for air extraction to offer advantage of zero oil gas pollution. The desorption process uses a set of circulating water tank heating system to provide plate heat source to aid the product reaching rapid drying. This study developed vacuum freeze-drying equipment for pharmaceutical and biotechnology industries, used vacuum freeze-dried 20% glucose solution and 20% saline solution to carry out vacuum drying on the samples, while the temperatures of the plates in preliminary drying were 20℃, 10℃, 0℃, -10℃ and -20℃, in order to discuss the effect of different plate temperatures on the sample temperature, pressure, and dryness. The experiment revealed that as the plate temperature is low and close to the sample temperature, the dryness is more satisfactory and the appearance is more intact. When the water loss for 20% glucose solution under plate temperature of -20C could reach 88%, and the appearance included irregular pores after freeze-dried. The water loss for 20% saline solution could reach 82%, and the appearance was more intact and showed loose chunks. During the drying process, low temperature measuring device and vacuum pressure gauge were installed to analyze the air extraction process, pressure change, and temperature change of the drying samples. The freezing temperature, air extraction speed, ultimate pressure, and water content of the dried products were measured. Micro observation system was used to observe the shape change of the product during the freeze-drying process in dynamic and real-time manner, thus, to ensure the product quality.

並列關鍵字

lyophilization ； freeze-drying

參考文獻

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