摘要: | 球型結晶是一項具突破性的粉體技術,不僅縮短製程步驟,也增加產品的可壓縮性、包裝性和流動性等。節能減碳雖是全球性重要議題,球晶能節省多少能源卻很少被探討。本研究以苯甲酸為系統,比較球晶製程和傳統再結晶在過濾和乾燥過程中的差異,及改變過程參數對乾燥結果的影響。本研究第一部分透過再結晶和球晶技術分別製備細小的苯甲酸晶體和其球狀結晶,通過真空幫浦過濾,從而計算流體通過時間與壓力計算濾餅阻力,發現球晶濾餅之過濾速度較細小晶體濾餅之過濾速度提升將近四倍;接著將產物放入烘箱內進行乾燥實驗,紀錄失重與時間的關係。可以發現球晶製程不僅使初始含水率下降、乾燥時間縮短和總乾燥速率提升,乾燥曲線和乾燥過程中內部機制也不盡相同。球晶製程相較於再結晶製程可節省70 %用於乾燥的能量。第二部分則比較不同參數條件下對球晶乾燥的影響,針對單一參數分別進行討論。包括洗滌操作存在的必要、改變批次中橋接液體積和種類、被乾燥物料的重量和烘箱內的溫度。發現洗滌操作和改變橋接液體積對苯甲酸球晶系統的乾燥行為影響不大,橋接液種類和被乾燥物料的重量對乾燥行為有較為顯著的差異,乾燥溫度的變化對乾燥曲線和能源消耗都會造成影響。這些實驗數據對於未來放大製程有著非常大的參考價值。;Spherical agglomeration is a breakthrough in powder technology that offers numerous advantages, including the shortening of processing steps and improvement in compressibility, packability, and flowability of products. Although the potential of saving energy by spherical agglomeration is crucial in the context of energy conservation and carbon reduction, it has been underexplored. In this study, we focused on the system of benzoic acid, and compared the effects of spherical crystallization and conventional recrystallization on its filtration and drying process. The influence of process parameters on drying behavior would also be considered by us. In the first part, fine benzoic acid crystals and spherical agglomerates were prepared separately by recrystallization and spherical agglomeration, respectively. Vacuum filtration was performed to measure the passing time of washing water and pressure drop across the filter cake, the results demonstrated more than three times improvement in filtration efficiency for the spherical agglomerates. Subsequently, drying experiments were conducted in a drying oven, recording the weight loss of the wet cake versus time. We found that spherical agglomeration not only reduced the initial moisture content and shortened drying time but also enhanced the overall drying rate, with distinct drying curves and internal mechanisms compared to the ones of recrystallization. Notably, the spherical agglomeration of benzoic acid resulted in 70% in energy savings during drying. In the second part, the effects of different operation parameters conditions on the drying behavior of spherical agglomerates were investigated individually. The study involved examining the necessity of washing operation, varying the volume and type of bridging liquid, the amount of dried sample, and controlling the oven temperature. The results revealed that washing operation and changes in bridging liquid volume had minimal impact on the drying behavior of benzoic acid round granules, while the choice of bridging liquid type and the weight of material had shown more significant differences in drying behavior. The varying of drying temperatures influenced both the drying behavior and total energy consumption. Those experimental attempts have provided valuable insights for further scale-up processes. |