Pellets, properties

J. J. Poveromo, "AISI Survey of Blast Eumace Pellet Properties," in Proceedings, 52nd Ironmaking Conference, AIME-ISS, Dallas, Tex., 1993. 

Podczeck F. Powder, granule and pellet properties for filling of two-piece hard capsules, Chapter 5 in Pharmaceutical Capsules, 2nd ed. In Podczeck F, Jones BE, eds. London Pharmaceutical Press, 2004, 108. 

A most comprehensive report of the early work in the US on waxes for use in Compn A type expls is published as Ref 33. It covers all the work conducted on wax for use with RDX during the period of 15 Feb 1942 to 27 Dec 1945. Methods used in prepn, pelleting properties, sensitivity and stability characteristics of the 91/9 RDX/wax compns are discussed in detail. In addition exptl compns of RDX/wax/A1 and RDX/wax/KN03 are briefly mentioned The 90/10 Aristowax 160-65/Alox 600, also known as Bruceton Wax No 10, was used thruout WWII. It was used in both Compn A and in Compn B. The Alox 600 used generally contains small quantities of resinous material insoluble in molten wax. The Alox 600 also is believed to be responsible for some of the stickiness and wax exudation of the Compn A. Recommendation was made to decrease the concn of Alox 600 from 10% to 1% in Wax No 10 to reduce these... 

Constraints on inclusion levels of certain ingredients, based on non-nutritive characteristics such as palatability and pelleting properties. 

The last assumption is referred to as the quasi-steady-state assumption. The fraction of the bed which is poisoned is a function of time only and not of bed length, reactor space time, or the concentration of the reactant A external to the pellets. At any given time the bed activity will be constant, and only one concentration of the poison precursor species S will exist in the bed. Such a situation will be more likely to occur when deactivation rates are low compared to reaction rates. Under this condition S will spread evenly throughout the bed. Within particles, however, concentration gradients of S may still exist depending on the poisoning mechanism and the pore and pellet properties. 

The data of Table II indicate that pellet production is not sensitive to contained moisture over a wide range. Some moisture is needed for die lubrication and pellet cohesion high moisture content results in a scaly, loose-bound pellet which breaks more easily in handling than others. Considering both equipment operations and pellet properties, the preferred moisture content is judged to be in the range 15 - 20%. 

Rates were measured at — 196°C and 1 atm pressure for pellets of three densities. The rate of reaction was also measured for the catalyst in the form of 60-micron (average size) particles. With this small size 1, so that / = 1.0. The rate data and pellet properties are given in Table 11-5. 

In an ideal fixed-bed reactor, plug flow of gas is assumed. This is, however, not a good assumption for reactive solids, because the bed properties vary with position, mainly due to changing pellet properties (and dimensions in most cases), and hence the use of nonideal models is often necessary. The dispersion model, with all its limitations, is still the most practical one. The equations involved are cumbersome, but their asymptotic solutions are simple, particularly for systems... 

T. Umadevi et ah, Influence of Pellet Basicity (CaO/Si02) on Iron Ore Pellet Properties and Microstructure, /57J/nter iatona/, 51 (1) (2011),14-20. 

Fuel pellet properties PuAl4 in A1 with A1 clad Pu02 in Z1O2 with Zr clad PuZrH 1,6 with Zr ciad... 

We used RX-55-AE-5 sample material (LLNL lot PR 1640) for this work the designation RX-55-AE-5 refers to a research explosive synthesized and processed at LLNL. Pellets of each explosive were uniaxially-pressed in a conventional compaction die without mold release, using a two pressing cycles of 5 minutes at 200 MPa for the larger pellets. The RX-55-AE-5 pellets were pressed at 105 C and obtained densities 1.74 g/cc to 1.75 g/cc (91.0% to 91-5 % theoretical maximum density), TMD) [5]. Pellet properties are summarized in Table 2. 

When the step change in trace species is made to the left hand side of the cell the shape of the resiMnse on the opposite, i.e. right hand side, is more dependent on the pellet properties than that on the left hand side the latter tends to be dominated by the mixing characteristics within volume V. The transfer function relating Cp(s) to C (s) can be shown to be of the form given in equation 11. 

The differential material balances contain a large number of physical parameters describing the structure of the porous medium, the physical properties of the gaseous mixture diffusing through it, the kinetics of the chemical reaction and the composition and pressure of the reactant mixture outside the pellet. In such circumstances it Is always valuable to assemble the physical parameters into a smaller number of Independent dimensionless groups, and this Is best done by writing the balance equations themselves in dimensionless form. The relevant equations are (11.20), (11.21), (11.22), (11.23), (11.16) and the expression (11.27) for the effectiveness factor. 

DRI can be produced in pellet, lump, or briquette form. When produced in pellets or lumps, DRI retains the shape and form of the iron oxide material fed to the DR process. The removal of oxygen from the iron oxide during direct reduction leaves voids, giving the DRI a spongy appearance when viewed through a microscope. Thus, DRI in these forms tends to have lower apparent density, greater porosity, and more specific surface area than iron ore. In the hot briquetted form it is known as hot briquetted iron (HBI). Typical physical properties of DRI forms are shown in Table 1. 

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