INDEX vessels

Pattemators may comprise an array of tubes or concentric circular vessels to coUect Hquid droplets at specified axial and radial distances. Depending on the pattemator, various uniformity indexes can be defined using the accumulated relative values between the normalized flow rate over a certain sector or circular region and a reference value that represents a perfectly uniform distribution. For example, using an eight-sector pie-shaped coUector, the reference value for a perfectly uniform spray would be 12.5%. The uniformity index (28) could then be expressed as foUows, where is the normalized volume or mass flow rate percentage in each 45-degree sector. 

Contrac tors bids offer the most rehable information on cost. Order-of-magnitude costs, however, may be required for preliminary studies. One way of estimating them is to obtain cost information from similar facihties and scale it to the proposed installation. Costs of steel storage tanks and vessels have been found to vaiy approximately as the 0.6 to 0.7 power of their weight [see Happel, Chemical Process Economics, Wiley, 1958, p. 267 also Williams, Chem. Eng., 54(12), 124 (1947)]. AU estimates cased on the costs of existing eqiiipment must be corrected for changes in the price index from the date when the equipment was built. Considerable uncertainty is involved in adjusting data more than a few years old. 

In Figure 10.30 the predietive neural network model traeks the ehanging dynamies of the plant. Following a suitable time delay, em(kT) is passed to the performanee index table. If this indieates poor performanee as a result of ehanged plant dynamies, the rulebase is adjusted aeeordingly. Riehter (2000) demonstrated that this teehnique eould improve and stabilize a SOFLC when applied to the autopilot of a small motorized surfaee vessel. 

Inhalt, m. content, contents (of a surface) area (of a body) volume (of a vessel) capacity index. 

The vessels were indexed by the subscript "j" (j = 0 refers to the reactor and j from 1 to 4 to the UF cells) and oligomers were lumped in two categories "P" (Permeated) and "R" (Rejected). Let label "in" species entering a cell and "out" those leaving it. Instantaneous mass-balance in the stream leaving a cell and feeding the following one is ... 

The same index n is used for the timings of the polymerization starts and the timings of the mixing vessel holdup steps since each mixing vessel holdup step corresponds exactly to one polymerization start. 

GENERAL NOTE Titles of referenced standards not listed in the Specifications Index for Mandatory Appendix IX are as follows A 20, General Requirements for Steel Plates for Pressure Vessels, and A 370, Test Methods and Definitions for Mechanical Testing of Steel Products. 

The UOP rotary valve has been used in hundreds of Sorbex units across a variety of applications. The purpose of the rotary valve is to simply move the inlet and outlet ports of the net streams (feed, desorbent, raffinate, extract) around the 24 beds in stepwise fashion, creating a semi-continuous countercurrent flow of adsorbent relative to the entry and exit points of the net streams to and from the adsorbent chambers [25]. The rotary valve consists of a rotor plate pressed against a stator plate inside a pressure vessel that indexes the net desorbent, feed, extract and raffinate streams around the adsorbent chambers [26]. An alternative method of moving the inlet and outlet streams around the adsorbent chambers is used in other technologies where multiple automatic on-off valves at each distributor grid inlet are employed [5]. 

The extraction vessel outlet valve can be controlled either manually from the control unit or automatically by the phase boundary detector unit. The operation of this detector is based on the difference in refractive index between the organic and aqueous phases, and has been described elsewhere [34]. 

The gas molecules fly about and among each other, at every possible velocity, and bombard both the vessel walls and collide (elastically) with each other. This motion of the gas molecules is described numerically with the assistance of the kinetic theory of gases. A molecule s average number of collisions over a given period of time, the so-called collision index z, and the mean path distance which each gas molecuie covers between two collisions with other molecules, the so-called mean free path length X, are described as shown below as a function of the mean molecule velocity c the molecule diameter 2r and the particle number density molecules n - as a very good approximation ... 

The correlation between the TEARS assay and MDA dnring oxidation of edible oils may be complicated by the presence of tocopherols (e.g. Vitamin E, 21) . An evaluation was carried of MDA, determined by an independent method , and TEARS as indices for direct oxygen uptake of edible oils and unsatnrated fatty acids. The linear increase of MDA and TEARS with oxygen consumption of soybean oil, in a closed vessel at 170 °C, stops when the latter value reaches 500 p.molL, when both MDA and TEARS start to decrease on further O2 consumption. The same process carried out at 40 °C, using 2,2 -azobis(2,4-dimethylvaleronitrile) (171) as initiator, shows linearity up to 1500 p,molL O2 consumption . A similar behavior is observed for nnsatnrated fatty acids snch as oleic, linoleic and linolenic acids . On the other hand, depletion of Vitamin E (a-tocopherol, 21) and its analogs y- and 5-tocopherol (172, 173) present in the oil show a linear dependence on O2 consumption of the oil, np to 1800 p,molL . This points to the consumption of these antioxidants, and especially 21, as a good index for the O2 uptake in oils at high temperature. The determination of the tocopherols is carried ont by HPLC-FLD (Xex = 295 nm, Ah = 325 nm) . ... 

With an approximate volume of 4 ml, the vitreous is the largest structure within the eye. It has a refractive index of 1.33 and consists of 98-99% water with a scaffold of collagen fibres and macromolecules of hyaluronic acid winding through the scaffold. The healthy human vitreous does not contain blood vessels and has a consistency comparable to that of egg white. 

When performing scale-up tests, be sure to take enough samples to give an accurate description of the mixture state in the vessel. Furthermore, be wary of how you interpret your samples know what the mixing index means and what your confidence levels are. 

A pressure glass vessel was charged with a cyclohexane solution of butadiene (60 g) and styrene (15 g) and treated with 11.7 ml of the step 1 product and the mixture polymerized at 50°C for 2.5 hours. The conversion was approximately 100%. Thereafter, 0.5 ml of 5% 2,6-di-f-butyl-p-cresol dissolved in isopropanol was added and the mixture precipitated in an isopropanol solution containing slight amounts of hydrochloric acid and BHT. The mixture was dried and the product isolated having an Mn of 1.74 x 105Da with a polydispersity index (PDI) of 1.02 and MLi+4 (100°C) of 22. 

---