纤维素超声微细化处理效果的影响因素研究  

Research on the Influencing Factors of Cellulose Ultrasonic Micronization

作　　者：付汨 孙世琪 刘斌[1] FU Mi;SUN Shiqi;LIU Bin(College of Material and Mechanical Engineering,Beijing Technology and Business University,Beijing 100048,China)

机构地区：[1]北京工商大学材料与机械工程学院,北京100048

出　　处：《农产品加工》2020年第6期34-38,共5页Farm Products Processing

基　　金：国家重点研发计划资助项目(2016YFD0400305)。

摘　　要：采用20 kHz超声破碎装置对纤维素进行微细化处理,研究了圆柱形料腔内影响微细化效果的因素:超声声源功率、微细化处理时间和料腔声场几何条件(液位高度)。应用有限元方法获取破碎装置中超声空化能的区域分布,根据空化能的区域分布特性,选择不同液位高度,对2种超声声源功率条件下不同处理时间后的微细化效果进行了试验验证和对比分析。结果表明,超声处理时间2 min内效率最高,纤维素粒径显著降低,D50为41μm,处理时间增加至20 min时,D50为25μm;低功率情况下,谐振液位条件下空化能量增强,与非谐振液位相比,处理时间为2 min时,纤维素粒径D50值小于14μm;高功率条件下出现声致流动,导致空化区域扩散增大,与低功率条件相比,相同处理时间纤维素粒径D50值明显降低。The effect of ultrasonic source power,micronized treatment time and geometric condition of material cavity sound field(liquid level height)for cellulose's ultrasonic micronization in cylindrical cavity were studied with the use of 20 kHz sonoreactor.Used the finite element method to obtain the area distribution of ultrasonic cavitation energy in crushing device.Selected different liquid level height according to the regional distribution characteristics of cavitation energy,the experimental verification and comparative analysis were carried out for the micronization effect after different processing time under the two ultrasonic source power conditions.Research indicated that the ultrasonic treatment time had the highest efficiency within two minutes,the cellulose's particle size decreased significantly and the value of D50 was 41μm.When the processing time increased to 20 min,D50 reached 25μm;When the power was low,the cavitation energy increased at resonance liquid height.Compared with the non-resonant liquid level,the D50 of cellulose particle diameter was about 14μm smaller when the processing time was 2 min;high power condition would cause acoustic flow,which increased the diffusion of cavitation area.Compared with the low power condition,the D50 value decreased obviously under the same treatment time.

关 键 词：纤维素 超声破碎 微细化处理 D50 

分 类 号：TS219[轻工技术与工程—粮食、油脂及植物蛋白工程]