Internal batch

With known analyte concentrations, the processed data provide calibration points, and Immusoft comprises fitting procedures to deduce the corresponding calibration curve that can be stored in the program for further experiments. Different calibration curves can be stored depending for instance on the assay protocol, on the specific features of the chip used or on the medium in which the assay is performed. In most cases, the calibration is performed with six independent chips of eight channels and cumulated in order to get a stable batch calibration. Then the results can be referred to this internal batch calibration. For routine control, one calibration each week is recommended to be sure that the chemistry is still in the specifications (e.g. + 10% of inter-assay standard deviation). 

As pointed out at the beginning of the chapter, when designing a new polymer processing operation to produce a product or to blend or compound a new material, it is often desirable or necessary to work on a smaller scale such as a laboratory extruder, internal batch mixer, stirring tank, etc. The evolving model must then be scaled up or down to the actual operation. 

Internal batch mixers can sometimes be simplified to a system such as the one shown in Fig. 6.77. For h R, the system can be further simplified by unwrapping the material from the cylinder and modeling it using rectangular coordinates. 

Figure 6.77 Schematic diagram of a simplified internal batch mixer geometry.

The NPD functions for characterizing dispersive mixing in internal batch mixers were developed by Manas-Zloczower et al. (57-60) and for SSEs by Manas-Zloczower and Tadmor (61).They were formalized and generalized by Tadmor (62,63). 

Fig. 10.5 Photograph and cross-sectional schematic representation of a Banbury high-intensity internal batch mixer. The photograph shows the two elements of the drive the electrical motor and the gear reducer. Their large size is due to the very large power requirements of the mixer. [Photograph courtesy of the Farrel Company, Ansonia, CT.]...

Internal batch mixers are batch systems that have both a lower-shear homogenizing region and a localized high-shearing section. Refer to the schematic disgram in Figure 6.20. 

Several basic designs of the internal batch-type mixers are available. The most popular are the laboratory mixers manufactured by, e.g., Brabender or Haake, and their homologues on the larger scale manufactured by, e.g., Banbury or Moriyama dispersion mixers. 

Studies of chemical kinetics in glassware and internal batch mixers. 

Internal batch mixers are widely used in the rubber industry. They are also used for processing plastics such as vinyl, polyolefins, ABS, and polystyrene, along with thermosets such melamines and ureas because they can hold materials at a constant temperature. 

The principle of internal batch mixing was first introduced in 1916 with the development of the Banbury mixer (Figure 2.74a). A Banbury-type internal mixer essentially consists of a cylindrical chamber or shall within which materials to be mixed are deformed by rotating blades or rotors with protrusions. The mixer is provided with a feed door and hopper at the top and a discharge door at the bottom. As the rubber or mix is worked and sheared between the two rotors and between each rotor and the body of the casing, mastication takes place over the wide area, unlike in a open mill where it is restricted only in the area of the nip between the two rolls. 

MWCNT/PP nanocomposites were prepared by melt blending at 200°C with a rotor speed of 60 rpm using an internal batch mixer. SEM images of the fracture surface in the composites demonstrated that PS-grafted MWCNTs were dispersed well in... 

Simulating Flows in Internal Batch Mixers with 2-D Models. 871... 

This section presents various examples and applications of three-dimensional simulation using finite element and boundary element techniques. These are presented to offer the reader an idea of what is possible with the current state-of-the-art of simulation programs. As examples, the authors have chosen cases that are of great interest to the academic, as well as, the industrial research community. These are internal batch mixers, extrusion dies and extrusion mixing sections. 

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