Nozzle types

Another type of distributor, not shown in Fig. 14-64, is the spray nozzle. It is usually not recommended for hquid distribution for two reasons. First, except for small columns, it is difficult to obtain a uniform spray pattern for the packing. The fuU-cone nozzle type is usually used, with the need for a bank of nozzles in larger columns. When there is more than one nozzle, the problem of overlap or underlap arises. A second reason for not using spray nozzles is their tendency toward entrainment by the gas, especially the smaller droplets in the spray size distribution. However, some mass transfer in the spray can be expected. 

Volume of vessel (free volume V) Shape of vessel (area and aspect ratio) Type of dust cloud distribution (ISO method/pneumatic-loading method) Dust explosihility characteristics Maximum explosion overpressure P ax Maximum explosion constant K ax Minimum ignition temperature MIT Type of explosion suppressant and its suppression efficiency Type of HRD suppressors number and free volume of HRD suppressors and the outlet diameter and valve opening time Suppressant charge and propelling agent pressure Fittings elbow and/or stub pipe and type of nozzle Type of explosion detector(s) dynamic or threshold pressure, UV or IR radiation, effective system activation overpressure Hardware deployment location of HRD suppressor(s) on vessel... 

FIG. 26-70 Accuracy in HEM predictions for slightly to moderately siibcooled flashing flow. Comparison with data for water by Sozzi and Sutherland (1975) also ASME Symposium on Non-Equilibrium Two-Phase Flows (1975) (Nozzle type 2). 

The pressure relief device used most often in refinery and chemical plant equipment is the spring-loaded, top-guided, high-lift, nozzle-type safety relief valve, which is illustrated in Figure 2. The spring is usually external and enclosed by a bonnet for weather protection, and the bonnet chamber is vented through an internal passage to the valve outlet. 

Coker, A. K., A Study of Fast Reactions in Nozzle Type Reactors, Ph.D. Thesis, Aston University, 1985. 

Safety-Relief Valve this is an automatic pressure-relieving device actuated by the static pressure upstream of the valve and characterized by an adjustment to allow reclosure, either a pop or a non-pop action, and a nozzle type entrance and it reseats as pressure drops. It is used on steam, gas, vapor and liquid (with adjustments), and is probably the most general tyqDe of valve in petrochemical and chemical plants (Figures 7-3, 7-3A, and 7-4). Rated capacity is reached at 3% or 10% overpressure, depending upon code and/or process conditions. It is suitable for use either as a safety or a relief valve [1,10]. It opens in proportion to increase in internal pressure. 

The stamped capacity of a spring loaded safety or safety relief valve (nozzle type) when installed with a rupture disk device between the inlet of the valve and the vessel shall be multiplied by a factor of 0.80 of the rated relieving capacity of the valve alone, or alternatively, the capacity of such a combination shall be established in accordance with Par. 3 below ... 

Feed nozzle type Insert material Nozzle tip... 

Note that in lieu of testing, Par (b) 2 and (b) 3 above allows the use of a capacity factor of 0.80 as a multiplier on the stamped capacity of the spring loaded safety relief valve (nozzle type). Some manufacturers test specific valve/rupture disk combinations and determine the actual capacity factor for the combination, and then use this for the net capacity determination. See Figures 7-10, 7-11, 7-12, 7-13A and 7-13B. 

Spray nozzle type plays an important role in the success of agrochemical application. For broadcast applications to soil, flat fan nozzles should be used. Newer spray tips such as the DG TeeJet, XR TeeJet, Turbo TeeJet and similar nozzles supplied by Lechler and Hardy have provided acceptable results in a number of studies. For a given nozzle type, the lower the application pressure, the larger is the spray droplet size and the less potential for spray drift. Similarly, the closer the boom is positioned to the soil surface, the less is the potential for spray drift." Most applications are made with spray tips having 80° or 110° spray angles and boom heights of about 50 cm above the soil surface. 

Abanades, S. and Flamant, G., Production of hydrogen by thermal methane splitting in a nozzle-type laboratory-scale solar reactor, Int. J. Hydrogen Energ., 30,843, 2005. 

All experiments were set np so as to be realistic scenarios with respect to multivariate statistical process control (MSPC). The pilot plant grannlator is operated exactly as the industrial scale counterpart, but most of the experiments inclnded mnch more severe variation than will usually be found in an otherwise stable industrial production sitnation of similar duration (e.g. it is normally not necessary to change nozzle types, or to change prodnct types within snch short intervals). 

For the case of equal density but differently sized particles fluidized in a bed with a nozzle-type distributor, Geldart (1992) recommends operating the bed at a gas velocity of 1.5 Ucf, where m / is the minimum velocity for complete fluidization, which may be well above the minimum fluidizing velocity found by the usual experimental method. 

A long, hollow, cylindrical bowl is suspended by a flexible spindle and driven from the top as shown in Figure 13. Axial ribs in the bowl ensure full acceleration of the liquid during its short time in the bowl. Feed is jetted into the bottom of the bowl and clarified liquid overflows at the top, leaving deposited solids as compacted cake on the bowl wall. The clarifying performance of the bowl is reduced as the deposited cake decreases the effective outer radius of the bowl in accordance with equation 11. Consequently, cake capacity of the industrial model is limited to 0.1—10 L. For liquid—liquid separation, the interface position (eq. 26) is determined by selection of ring-dam diameter or by the length of a hollow nozzle-type screw dam. 

Anklam et al. [91] have attempted to measure the extensional rheological properties of w/o emulsions and HIPEs, using a nozzle-type viscometer. However, the results showed a dependence on the nozzle size used, and long relaxation times. Experiments on other non-Newtonian fluids indicated that it was not possible to obtain reliable results with this kind of instrument. 

Figure 18 Atomizing air volume and nozzle type for laboratory, pilot, and production...

Figure 14 Influence of spray nozzle type and atomizing air pressure on the mean droplet size of water sprayed from guns used in a Wurster process.

Although pneumatic mixers may differ from one another in vessel geometry, air nozzle type, and air nozzle configuration, no pneumatic mixer subclasses have been identified. 

There is information available on the droplet size generated from 3 of the more common nozzle types used on air blast equipment (13) The physical/chemical properties of the spray formulation and its end use dilution can have a marked influence on the droplet as it travels from the nozzle, resulting in a large decrease in diameter. There is presently inadequate information to enable accurate estimates of droplet size distribution at varying distances from the spray nozzle. These changes may not be important in estimating direct contact to the workers but become... 

Nozzle The second part of the seat ensuring the tightness of the valve. For full nozzle-type valves, it is usually integral, is screwed into the body and protects the body from the medium. It also forms the mating face of the flange... 

Nozzle Type Full [ ] Semi [ ] 19. Scat (Nozzle) Disk ... 

System Nozzle type Operation mode Volumetric mass transfer coefficient, s l Ref. 

Wen and Fan [6] have provided a comprehensive listing of various tracers and experimental techniques for determining the RTD in flow systems. Recent studies [10,11,12] have been performed employing an impulse tracer to determine the RTD in bubble columns and an oscillatory flow electrochemical reactor. The author [13,14] has employed both step-change and an impulse to determine the RTD of nozzle type reactors analysis of the RTD involves an atomic absorption spectrophotometer (AAS), a cine-projector, and a chart recorder. Figures 8-7 and 8-8 show the nozzle-type reactors and the AAS, respectively. Figure 8-9 gives a typical response curve from the AAS. 

Spray nozzle type and number Percentage weight gain... 

The A-starch slurry from the centrifugal decanter is screened and then refined either with hydrocyclones or with separators and decanters. Purification and concentration of A-starch is accomplished in multistage hydrocyclones, or the A-starch slurry is separated into A and B fractions in a nozzle-type centrifuge and the A-starch fraction is finally refined in a centrifugal decanter. The B-starch stream is passed through vibrating screens and concentrated in a decanter. Pentosans and other solubles are concentrated and either dried or co-fermented with the B-starch for ethanol production. 

Define nozzle type, number, position, orientation, liquid flow rates, source pressure, etc. 

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