[雙語(yǔ)翻譯]機(jī)械外文翻譯--比較單軸和雙軸料倉(cāng)攪拌機(jī)的混合性能（英文）

1、Comparing mixing performance of uniaxial and biaxial bin blendersAmit Mehrotra, Fernando J. Muzzio ?Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, NJ, 08855, United Statesa b s t r a

2、c t a r t i c l e i n f oArticle history:Received 17 February 2009Received in revised form 30 May 2009Accepted 14 June 2009Available online 27 June 2009Keywords:Powder mixingCohesionBlenderMixerRelative standard deviatio

3、nNIRAcetaminophenThe dynamics involved in powder mixing remains a topic of interest for many researchers; however thetheory still remains underdeveloped. Most of the mixers are still designed and scaled up on empirical b

4、asis.In many industries, including pharmaceutical, the majority of blending is performed using “tumblingmixers”. Tumbling mixers are hollow containers which are partially loaded with materials and rotated forsome number

5、of revolutions. Some common examples include horizontal drum mixers, v-blenders, doublecone blenders and bin blenders. In all these mixers while homogenization in the direction of rotation is fast,mediated by a convectiv

6、e mixing process, mixing in the horizontal (axial) direction, driven by a dispersiveprocess, is often much slower. In this paper, we experimentally investigate a new tumbling mixer that rotateswith respect to two axes: a

7、 horizontal axis (tumbling motion), and a central symmetry axis (spinningmotion). A detailed study is conducted on mixing performance of powders and the effect of criticalfundamental parameters including blender geometry

8、, speed, fill level, presence of baffles, loading pattern,and axis of rotation. In this work Acetaminophen is used as the active pharmaceutical ingredient and theformulation contains commonly used excipients such as Avic

9、el and Lactose. The mixing efficiency ischaracterized by extracting samples after pre-determined number of revolutions, and analyzing them usingNear Infrared Spectroscopy to determine compositional distribution. Results

10、show the importance of processvariables including the axis of rotation on homogeneity of powder blends.© 2009 Elsevier B.V. All rights reserved.1. IntroductionParticle blending is a required step in a variety of app

11、licationsspanning the ceramic, food, glass, metallurgical, polymers, andpharmaceuticals industries. Despite the long history of dry solidsmixing (or perhaps because of it), comparatively little is known of themechanisms

12、involved [1–3]. A common type of batch industrial mixeris the tumbling blender, where grains flow by a combination of gravityand vessel rotation. Although the tumbling blender is a very commondevice, mixing and segregati

13、on mechanisms in these devices are notfully understood and the design of blending equipment is largelybased on empirical methods. Tumblers are the most common batchmixers in industry, and also find use in myriad of appli

14、cation as dryers,kilns, coaters, mills and granulators [4–8]. While free-flowingmaterials in rotating drums have been extensively studied [9,10],cohesive granular flows in these systems are still not completelyunderstood

15、. Little is known about the effect of fundamental param-eters such as blender geometry, speed, fill level, presence of baffles,loading pattern and axis of rotation on mixing performance ofcohesive powders or the scaling

16、requirements of the devices.However, conventional tumblers, rotating around a horizontal axis,all share an important characteristic: while homogenization in thedirection of rotation is fast, mediated by a convective mixi

17、ng process,mixing in the horizontal (axial) direction, driven by a dispersiveprocess, is often much slower.In this paper, we experimentally investigate a new tumbling mixerthat rotates with respect to two axes: a horizon

18、tal axis (tumblingmotion), and a central symmetry axis (spinning motion). We examinethe effects of fill level, mixing time, loading pattern and axis ofrotation on the mixing performance of a free-flowing matrix of FastFl

19、o lactose and Avicel 102, containing a moderately cohesive API,micronized Acetaminophen. We use extensive sampling to character-ize mixing by tracking the evolution of Acetaminophen homogeneityusing a Near Infrared spect

20、roscopy detection method. After materialsand methods are described in Section 2, results are presented inSection 3, followed by conclusions and recommendations, which arepresented in Section 4.2. Materials and methodsThe

21、 materials used in the study are listed in Table 1, along withtheir size and morphology. Acetaminophen is blended with com-monly used excipients and is used as a tracer to evaluate the degree ofhomogeneity achieved as a

22、function of number of revolutions.Acetaminophen is one of the drugs most widely used in mixingstudies, and Avicel and Lactose are commonly used pharmaceuticalPowder Technology 196 (2009) 1–7? Corresponding author. Tel.:

23、+1 732 445 3357; fax: +1 732 445 2581.E-mail address: muzzio@sol.rutgers.edu (F.J. Muzzio).0032-5910/$ – see front matter © 2009 Elsevier B.V. All rights reserved.doi:10.1016/j.powtec.2009.06.008Contents lists avail

24、able at ScienceDirectPowder Technologyjournal homepage: www.elsevier.com/locate/powtecFig. 2. Pictorial representation of (a) bin blender 1 and (b) bin blender 2 showing the corresponding axis of rotation.Fig. 3. Schemat

25、icof the loading patternusedinthestudy. Intop–bottomloading,Avicel isloaded first intotheblender followedby Lactoseon topofitandfinally Acetaminophenisuniformlysieved over. In side–side loading avicel is placed at the bo

26、ttom and then Acetaminophen is only sieved only in half part of the blender and is sandwiched between lactose and Avicel.Fig. 4. (a) Thief sampler (b) top view of the sampling position scheme.Fig. 5. Mixing curves for di

27、fferent fill levels in blender 2. The RSD of acetaminophen is plotted as a function of number of revolutions. The loading pattern in top-bottom and theblender rotational speed is 15 rpm with spinning speed of 7.5 rpm.3 A