Dumping devices

Use of the bowl dumping device or vacuum unloading device still requires that the product bowl be removed from the unit. 

As with loading, the standard method for unloading is to remove the product bowl from the unit. Once the bowl is removed, the operator may scoop the material from the bowl, which is the most time-consuming and impractical method, because of the potential for exposur e to the product. Alternatively, the product can be vacuum-transferred to a secondary container or unloaded by placing the product bowl into a bowl dumping device, as shown in Figure 18. This hydraulic device is installed in the pro-... 

Figure 18 (a) Product discharge with a bowl dumping device, (continues)... 

Operating levers controlling hoisting/dumping devices must be equipped with a latch or other device which will prevent accidental starting or tripping of the mechanism. 

Sieve Plates. The conventional sieve or perforated plate is inexpensive and the simplest of the devices normally used. The contacting orifices in the conventional sieve plate are holes that measure 1 to 12 mm diameter and exhibit ratios of open area to active area ranging from 1 20 to 1 7. If the open area is too small, the pressure drop across the plate is excessive if the open area is too large, the Hquid weeps or dumps through the holes. 

FIG. 14-80 Cost of internal devices for columns containing dumped packings, a) Holddown plates and support plates, (h) Redistributors, (c) Liquid distributors. [Pikulik and Diaz, Cbem. Eng., 84(21), 106 (Oct. 10, 1977).]... 

The discharge of copious quantities of chemicals directly to the atmosphere can give rise to secondary hazards, especially if the materials are toxic and can form a flammable atmosphere (e.g., vapor or mist) in air. In such cases, the provision of a knockout device (scrubber, dump tank) of adequate size to contain the aerated/foaming fluid is required. 

Dump bailing method utilizes a bailing device that contains a measure volume of cement slurry. The bailer is run to the appropriate depth on a wireline and releases its load upon bumping the bottom or a permanent bridge plug set at the desired depth (see Figure 4-408). 

Conveyors, Mills Stop Devices, Coasting, Guards Emergencies Dump, Drown, Inhibit, Dilute... 

The present study was conducted in an effort to better understand ACC mechanisms and to design practical ACC based on pulsed liquid-fuel injection suitable for propulsion devices. The controller utilized a simple fixed phase-delay approach that has been studied previously, but the direct liquid-fuel injection and the novel use of vortex-droplet interaction made the present study unique. The demonstration experiment in a 102-millimeter dump combustor showed that combustion instabilities can be successfully suppressed using properly designed pulsed liquid-fuel injection. 

A comprehensive framework of robust feedback control of combustion instabilities in propulsion systems has been established. The model appears to be the most complete of its kind to date, and accommodates various unique phenomena commonly observed in practical combustion devices. Several important aspects of distributed control process (including time delay, plant disturbance, sensor noise, model uncertainty, and performance specification) are treated systematically, with emphasis placed on the optimization of control robustness and system performance. In addition, a robust observer is established to estimate the instantaneous plant dynamics and consequently to determine control gains. Implementation of the controller in a generic dump combustor has been successfully demonstrated. 

Oil and emulsion t low through a spreader into (lie back, or coalescing, section ot the vessel that is lluid packed. Tlic spreader distributes flow evenly throughout the length ol this section Treated oil is collected at the top by means of a collection device sized to maintain a uniform vertical oil flow Coalescing water droplets fall countercurrent to the rising oil continuous phase. The oil-water interface is maintained by a level controller and dump valve for this section of the vessel. 

Cross-flow devices. Equipment manufacturers have modified the CPI configuration for horizontal water flow perpendicular to the axis of plate corrugations. This allows plates to Lie installed at a steeper angle to facilitate sediment removal and enables the plate pack to be more conveniently packaged in a pressure vessel. The latter advantage is critical if gas blowby through an upstream dump valve could cause relief problems in an atmospheric tank. 

For relief-protection dump valves, relief valves, and finally rupture discs are used. The sizing of the relief devices is based on the rate of pressure-rise. The flow area should be large enough to stop the pressure rise as soon as the set pressure is reached. 

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