Wypych

G. Wypych (Ed.), Solvents Database on CD Rom, William Andrew Publishing, LLC 2001. ISBN 0815514638. SAFETY IN THE CHEMICAL LABORATORY... 

Wypych. P. W. and Arnold, P. C. Powder Technol. 50 (1987) 281. On improving scale-up procedures for pneumatic conveying design,... 

G. Wypych (ed.), Handbook of Solvents, ChemTec Publishing, Toronto (2001). 

Wood SJ, Wypych J, Steavenson S, Louis JC, Citron M, Biere AL. a-... 

Narhi L, Wood SJ, Steavenson S, Jiang Y, Wu GM, Anafi D, Kaufman SA, Martin F, Sitney K, Denis P, Louis JC, Wypych J, Biere AL, Citron M. Both familial Parkinson s disease mutations accelerate alpha-synuclein aggregation. J Biol Chem 1999 274 9843-9846. 

Both Reed and Bradley (1991) and Wypych and Arnold (1993) have given surveys of techniques to minimize the particle degradation. 

Selecting unsuitable hardware and/or mode of transport (Wypych, 1995a)... 

A significant number of developments have occurred over the past decade to address these important issues of pneumatic conveying (Wypych, 1995a). This chapter summarizes some of the major design considerations that have resulted from this work in relation to long-distance and pipe branching applications. 

Note the mean diameter used by Geldart (1973) is actually a surface volume mean diameter dsvm, based on Eq. (3). However, comparing the fluidization curves of several materials with the Geldart (1973) diagram (e.g., fly ash, pulverized coal, coarse ash, PVC powder and screened coke), Wypych (1989b) found the following ... 

Group A powders are the best candidates for dense-phase conveying and can achieve high solids/gas loadings. Note the dense-phase referred to here actually is fluidized dense-phase (Wypych, 1995a). 

The following comments are based on the findings of Wypych (1989b) who compared the actual conveying characteristics of several materials with the slugging classifications of Dixon (1979) and Dixon (1981). 

To emphasize some of the above comments and suggestions (as well as some of those presented earlier in relation to the Geldart [1973] diagram), the PVC powder results (Wypych, 1989b) are summarized below. 

This result was supported by the material s excellent air-gravity conveying performance (Wypych and Arnold, 1985a). Based on these results, it would be reasonable to assume that this material would be suited to fluidized dense-phase. 

If for a given material, Vmf > 50 mm s1 (i.e., above the boundary shown in Fig. 5) andX< 0.001 m3 s kg-1 (i.e., below the boundary shown in Fig. 6), then dense-phase low-velocity slug-flow (Wypych, 1995a) is possible (e.g., mustard seed, polyethylene powder, 1000 pm sand, polyethylene pellets and granulated sugar). Note that dilute-phase also is possible. 

Typical Group A materials (e g., cement, baghouse fly ash, pulverized coal, carbon fines) are the best candidates for fluidized dense-phase (Wypych,... 

Tandem 7 nf bottom-discharge cone-dosing blow tanks, similar to those shown in Fig. 8, were employed for this purpose and also to regulate the feed of material into the pipeline and alleviate the occurrence of imminent blockages (Wypych, 1995b). 

Wypych and Arnold (1985b) and hence, only a brief description is presented here. The test procedure basically consists of three different types of experiments which are applied to the material until sufficient data have been collected for the determination of conveying characteristics. The steady-state parameters generated specifically for this purpose are... 

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