Packings efficiencies

The interior surface of the stainless steel tubing is usually poHshed to allow the particles to pack efficiently. An important consideration is uniformity of the... 

In design practice, a less rigorous parameter, HETP, is used as an index of packing efficiency. Tne HETP is the height of packed bed required to achieve a theoretical stage. The terms Hoe and HETP may be related under certain conditions ... 

Structured packing efficiency is about 1.5 times that of plates or random packing. 

The structured packing efficiency is about 50% higher than either the trays or the random packing. 

It is found that the viscosity of a paste made from a fixed polymer/plasticiser ratio depends to a great extent on the particle size and size distribution. In essence, in order to obtain a low-viscosity paste, the less the amount of plasticiser required to fill the voids between particles the better. Any additional plasticiser present is then available to act as a lubricant for the particles, facilitating their general mobility in suspension. Thus in general a paste polymer in which the pastes have a wide particle size distribution (but within the limit set by problems of plasticiser absorption and settling out, so that particles pack efficiently, will... 

Bierwagen, G.P. and Saunders, T.E., 1974. Studies of the effects of particle size distribution on the packing efficiency of particles. Powder Technology, 10, 111-119. 

Packing material can be plastic, metal, or ceramic. Packing efficiencies can be expressed as HETP (height equivalent to a theoretical plate). 

Figure 9-8K. Spray nozzle distributor using full-cone wide-angle spray nozzles (depends on tower diameter). Not recommended for distillation applications, where the point-type distributors provide higher packing efficiency. Used by permission of Nutter Engineering, Harsco Corp., Bull. TI-1.

Packing efficient ) and capacity vary with specific application. Contact vendor for assistance in making final decision. 

Figure 9-211. Norton IMTP Packing, Efficient Capacity Correlation for random metal packing only for non-foaming systems. Norton recommends designing up to 90% of efficient capacity ...

Kunesh, John G. and A Shariat, Packing Efficiency Testing on a Commercial Scale with Good Reflux Distribution, Fractionation Research, Inc., presented at AIChE Spring National Meeting, Houston, Texas, March (1993). 

The liquid distributor is the most important internal structure of a packed column. The distributor strongly influences packing efficiency. It must spread the liquid uniformly, resist plugging/fouling, provide free space for gas flow, and allow operating flexibility. 

Packing efficiency is defined as the percent of the total volume of a solid occupied by (spherical) atoms. The formula is... 

The volume of one atom is firr3 and the volume of the cell is s3. Calculate the packing efficiency of... 

Such units are used in the watches with electronic drives instead of the traditional mechanical spring driven drives. Another area where the combination function is being used is in large-scale integrated circuit unit supports where the complex interconnection requirements make a combination circuit support and printed circuit unit an attractive way to achieve high packing efficiency such as computer hardware systems. 

Liquid crystal behavior is a genuine supramolecular phenomenon based on the existence of extended weak interactions (dipole-dipole, dispersion forces, hydrogen bonding) between molecules. For the former two to be important enough, it is usually necessary for the molecules to have anisotropic shapes, able to pack efficiently so that these weak interactions can accumulate and co-operate, so as to keep the molecules associated in a preferred orientation, but free enough to move and slide, as they are not connected by rigid bonds. 

Rigid particles with diameters greater than 20 micrometers can be dry-packed efficiently with relatively simple apparatus using the tap-fill method [149]. The empty column. is held... 

Solv=MeOH, EtOH and PrOH), and l,4-bis(4-pyridyl-butadiyne) (bpb, n= 0.5, Solv=MeOH). Like the btr derivative, compressed [FeN6] pseudo-octahedral sites define the knots of the square- or rhombus-shaped windows, which constitute the layered grid structure of the three compounds. Stacking of these layers in the crystal defines their most important structural differences, which are determined by the ligand size and crystal packing efficiency. In principle, the 2D grids are organised in a fashion similar to that described for the [Fe(btr)2(NCX)2]-H20 system the parallel layers are alternated so that the iron atoms of one layer lie vertically above and below the centres of the squares formed by the iron atoms of the adjacent layers. 

Packing efficiency can also be described by the extent of short-range order in the amorphous state. Mitchell has shown through X-ray scattering studies that, while the local molecular organization of noncrystalline polymers is random, in many cases, there are additional correlations that do not perturb the chain trajectory but will impact polymer properties.15 These correlations have a limited spatial range (<50A) but will have a particular impact on bulk properties... 

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