Directional feed nozzles

Total Resid Cracker Side-by-side configuration External straight vertical riser with two sets of multi-directional feed nozzles Two stage regeneration with external cyclones in the second stage... 

The fluidized-bed section of the calciner contained the air distributor plate, the bed drainage outlet, the feed nozzle, the product overflow line, and the bed charging line. An expanded filter section containing porous stainless steel filters and the off-gas vent line was located directly above the fluidized-bed section. 

At Chalmers University in Stockholm, the nozzles were etched laterally into the sihcon. A maximum hydrostatic counter pressure of 25kPa (for a pmnp with larger external dimensions) was measured following an optimization of the flare angle [322]. The pumps are suitable for direct feed of fluids and gases. Care is to be taken when shutting off valveless micropumps because the transported medium will flow back in the presence of a hydrostatic counter pressure. 

Another adverse spreading factor is associated with the spokes that form the supporting cage of the rotor assembly and interfere 8 times per revolution with the passage of feed streams from nozzles to rotors. A separate mathematical study (5) shows that the feed streams should be directed at 30° from normal in the direction of travel, to produce a minimum of 10% interruption of the water. 

Alternatively, multivane triangular diffusers (Fig. 14-7lb. c) such as the Schoepentoeter have been successful for high-velocity vapor-rich feeds. These are used with radial (as distinct from tangential) nozzles. The vanes knock out the liquid and direct it downward while the vapor expands to the tower diameter. 

A 2-liter stainless steel vessel, partially filled with I2 crystals, was connected directly to the secondary He feed supply line of a supersonic chemical laser. A complete description is given in a separate paper.- The laser cavity had viewing windows on top and bottom so that the nozzle array could be viewed in a direction perpendicular to the optical axis. The pump laser was a Spectra-Physics Model 170-03 Ar+ laser equipped with an intracavity etalon. 

Liquid feed is most often dispersed into the bed by a two-fluid spray nozzle which is flexible in operation and less prone to blockage, especially if heated air is used to atomize crystallizing liquors. Liquid feed may be directed onto the bed surface from the space above the upper bed surface or introduced directly beneath the surface of the bed material. The liquid spray is less likely to dry as a spray before contacting the bed particles in this latter arrangement. 

With the Laskin-type nozzle shown in Figure 9, a high velocity air jet issues directly into a liquid and entrains a filament of the liquid into droplets, which are carried to the surface and out. The nozzle is constructed of Teflon. A small orifice is drilled at right angles to the axis of the air feed line. A liquid feed hole is centered above the air orifice and longitudinal to the nozzle. 

Humidification. For winter operation, or for special process requirements, humidification may be required (see Simultaneous HEAT AND mass TRANSFER). Humidification can be effected by an air washer which employs direct water sprays (see Evaporation). Regulation is maintained by cycling the water sprays or by temperature control of the air or water. Where a large humidification capacity is required, an ejector which directly mixes air and water in a nozzle may be employed. Steam may be used to power the nozzle. Live low pressure steam can also be released directly into the air stream. Capillary-type humidifiers employ wetted porous media to provide extended air and water contact. Pan-type humidifiers are employed where the required capacity is small. A water filled pan is located on one side of the air duct. The water is heated electrically or by steam. The use of steam, however, necessitates additional boiler feed water treatment and may add odors to the air stream. Direct use of steam for humidification also requires careful attention to indoor air quality7. 

Spray. Direct type, continuous operation Suited for large capacities. Product is usually powdery, spheric, and free-flowing. High temperatures can be used with heat-sensitive materials. Product may have low bulk density See comments under Liquids. Pressure-nozzle atomizers subject to erosion Requires special pumping equipment to feed the atomizer. See comments under Liquids Not applicable Not apphcable Not applicable Not applicable Not applicable... 

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