Plate dispersion plug

Plate dispersion plug n. Two small, perforated, parallel disks joined by a central connecting rod. Such assemblies were sometimes inserted in the nozzles of ram-type injection-molding machines to improve the distribution of colorants in the resin as it flows through the nozzle. 

The H-Oil reactor (Fig. 21) is rather unique and is called an ebullated bed catalytic reactor. A recycle pump, located either internally or externally, circulates the reactor fluids down through a central downcomer and then upward through a distributor plate and into the ebullated catalyst bed. The reactor is usually well insulated and operated adiabatically. Frequently, the reactor-mixing pattern is defined as backmixed, but this is not strictly true. A better description of the flow pattern is dispersed plug flow with recycle. Thus, the reactor equations for the axial dispersion model are modified appropriately to account for recycle conditions. 

Phases gas-liquid, liquid-liquid, gas-liquid and solid (bio). Intermediate reaction rates. High capacity, high conversion in both gas and liquid phases. Intensive dispersion of gas in liquid. Large number of plates gives plug flow. Some flexibility in varying liquid holdup and exchange heat via cods on plates, d = 40-100 0.6 < Ha < 3. 

Venturi dispersion plug The Venturi dispersion plug is a plate having an orifice with a conical relief drilled into it. This is fitted into the nozzle of an injection molding machine to aid in the dispersion of colorants in the resin. 

Liquid-liquid extraction is carried out either (1) in a series of well-mixed vessels or stages (well-mixed tanks or in plate column), or (2) in a continuous process, such as a spray column, packed column, or rotating disk column. If the process model is to be represented with integer variables, as in a staged process, MILNP (Glanz and Stichlmair, 1997) or one of the methods described in Chapters 9 and 10 can be employed. This example focuses on optimization in which the model is composed of two first-order, steady-state differential equations (a plug flow model). A similar treatment can be applied to an axial dispersion model. 

Plate tower Disperse flow for liquid Non-plug-flow for gas 0.01-0.05 0.01-0.2... 

Parallel-plate electrodes Ethane polymerization Plug flow with axial dispersion Not applicable Assumed average electron density and energy 66... 

The caps are slotted around the lower periphery and can be anchored to the plate with teeth touching the plate or suspended to permit a so-called skirt clearance between the plate and the cap. Slots can be of a saw-tooth type or in the form of punched holes, usually rectangular or triangular. In common practice, a skirt clearance in the range of 0.5 to 1.5 in. is recommended to prevent plugging of the slots by residue buildup. Since the purpose of the slots is to disperse the gas into the liquid in the form of small bubbles, sufficient slot area should be provided in order that no gas may pass through the skirt clearance. 

One very important point that must be considered in any rheological measurement is the possibility of slip during the measurements. This is particularly the case with highly concentrated dispersions, whereby the flocculated system may form a plug in the gap of the platens, leaving a thin liquid film at the walls of the concentric cylinder or cone-and-plate geometry. This behaviour is caused by some syneresis of the formulation in the gap of the concentric cylinder or cone and plate. In order to reduce sHp, roughened walls should be used for the platens an alternative method would be to use a vane rheometer. 

The inhibition of A. parasiticus growth by [4] was determined in our laboratory using a modification of the assay reported by Amoldi and coworkers (M) stilbene was dissolved in acetone and appropriate amounts were added to sterile potato dextrose agar (PDA) at 50 C to give concentrations of 10, 20, 50, and 100 ug/ml. The medium was dispersed in 60 mm tissue culture dishes and inoculated with 4 mm PDA plugs of actively growing A. parasiticus cultures. Plates were incubated in the dark at 30 C and colony diameters were measured daily. After three days the percent inhibition of A. parasiticus growth at 10, 20, 50, and 100 ug/ml was 15, 26, 37, and 33%, respectively (unpublish data). 

A vertical assembly of elements, in conjunction with a high rate of liquid circulation, can represent plug flow with dispersion of the upward flowing gas and the high level of liquid backraixing typical of a bubble column. Plate columns and stirred vessels can be likewise represented by suitable assemblies as shown in Fig. 6. If a generalised sub-routine for the gas-liquid element were available, assemblies like those in Fig. 6 can be readily solved with a standard flowsheeting system. 

Mathematical models for different kinds of gas-liquid reactors are based on the mass balances of components in the gas and liquid phases. The flow pattern in a tank reactor is usually close to complete backmixing. In the case of packed and plate columns, it is often a good approximation to assume the existence of a plug flow. In bubble columns, the gas phase flows in a plug flow, whereas the axial dispersion model is the most realistic one for the liquid phase. For a bubble column, the ideal flow patterns set the limit for the reactor capacity for typical reaction kinetics. 

The glass plates are fastened and sealed round their edges with an adhesive a gap left in the edge seal allows the liquid crystal to be introduced and is plugged afterwards. Small, uniformly sized spacer particles may be added to the edge seal material and/or dispersed over the area of the display to maintain a constant spacing. 

Standard spacing of cross-flow plate packs is 0.80 in., with optional available spacing of either 0.46 or 1.33 in. The pack is inclined 60° to lessen plugging. More coalescing sites are offered to the dispersed oil droplets due to the hexagonal pattern of the pack. 

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