Drums location

This example is intended to demonstrate the process dynamics methodology as implemented on a single equilibrium stage. A stream of light hydrocarbons is sent to a distillation column where the C3 s and lighter components are separated from the C4 s. Since the feed composition fluctuates substantially, it is sent to a flash drum located upstream of the column in order to attenuate the composition fluctuations and thereby improve the column controllability. The vapor and liquid products from the flash drum are then sent to different trays in the column. 

The vapor product system in Fig. 9.3 is one example of a system that favors location C (60, 369). If the relief valve is upstream of the condenser (location A), the air condenser will be inert-blanketed and become completely ineffective during a power failure. A relief valve on the reflux drum (location C) will meiximize condensation. Location C also offers easier access to maintenance and a shorter blowdown line. 

Avoiding refluxing of the component back into the column A typical example is the reflux drum boot technique, commonly applied in hydrocarbon separations where water is the impurity. The boot may be an integral part of the drum (Fig. 13.4), or a separate drum located at ground level. Some guidelines for boot sizing are in Sec. 15.14. 

ISO 4577 [198] covers the thermal oxidative stability of polypropylene. Test pieces are mounted on a rotating drum located in a forced air circulating oven set to the preferred temperature value of 150 C, although where the effect of temperature on the stability is required, temperatures down to 100°C may be used (Fig. 34). The failure time in this standard is taken as the time in days for the test pieces to show localized crazing, crumbling. and or discoloration. 

Benali and Legros (2004) carried out an experimental study on thermal processing of particulate solids on a valved pulse combustion unit. The test bench consists of a 60 kW natural-gas-fired, valved (flappers) pulse combustor having a 4.63 X 10" m combustion chamber, horizontal tailpipe with variable geometry, and a cylindrical drum. The particulate solid used was clean sand (311 pm and 2646 kg/m ), which flows within the tailpipe and was collected by the cylindrical drum located at its end. The sand flow rate was varied from... 

BuUitt County, Kenmcky. One of the first sites selected for Superfund cleanup was an abandoned 30-acre site. It became known as the Valley of the Drums, located on the Smith Farm near Brooks, KY. Estimates indicated that 100,000-200,000 drums are buried or partially buried on the site. Some contain waste, but the contents of all are not known. There are numerous streams of leachate at the site. Many drain into a tributary to the Bluelick Creek, a source of drinking water for potentially 300 people. 

The ACS controls the system. Nine of 12 control drums located in the reflector are controlling members and are actuated by one automatic control (AC) drive located behind the radiation shielding. 

An alternate supply of process materials, catalysts, or reactants, such as temporary tanks or drums located within the facility. 

Within the conventional inline process unit, drums and their related items are generally located on either side of a central pipe rack serviced by auxiliary roads for maintenance access. In certain cases (e.g., for flash drums and deaerators), drums can be located above the pipe rack. In chemical plants, drums are generally located at all levels of enclosed or open-sided structures. For eixample, Exhibit 5-4 shows the drum location in a tower reflux system. Exhibit 5-5 shows the typical location of feed surge and compressor suaion drums, and Exhibit 5-6 shows the drum locations in an enclosed chemical plant stnicture. 

Drum Locations in an Enclosed Chemical Plant Structure... 

For tall vertical drums, platforms are usually circular and supported by brackets attached to the shell of the drum. Platforms at horizontal drums are usually rectangular and are supported by brackets attached to the concrete piers supporting the drum or trunnions attached to the shell of the drum, or by struaural steel supported from grade. Drums located in structures, if size permits, use the struaure floor for access to controls. Top head platforms on horizontal and vertical installations are supported by trunnions attached to the vessel head. Generally, access to freestanding drum platforms is by ladder. Typical drum platform arrangements are shown in Exhibit 5-19. 

If required, piping at horizontal freestanding drums should be supported from the shell of the drum, the platform steel, or the concrete piers supporting the drum. Piping associated with drums located within structures should be supported from the struaural steel. Exhibit 5-24 shows tjpical pipe supports at a horizontal drum, and Exhibit 5-25 shows a typical pump suaion arrangement... 

For example, on a long crude oil transportation pipeline, we might have periodic surge drums located along the line to safely accommodate a sudden stoppage of the flowing crude. 

The Piper Alpha Oil Platform in the North Sea, about 100 miles from Aberdeen, Scotland, exploded and was destroyed by fire in July 1988. One hundred and sixty-five people were killed. I was hired by Occidental Petroleum, the operator of the platform, to write an independent report of the catastrophe. The basic cause of the incident was clearly the release of light hydrocarbons (propane, butane, pentanes) associated with a condensate flash drum located on the production platform. 

Hot well The drum located below a surface condenser in vacuum service, where the barometric legs drain to. 

It is to be remembered that in this type of configuration, i.e., coil-soaker, the bulk of the cracking reaction occurs not in the furnace (coil reactor) but in a drum located after the furnace (soaker). Hence, low residue conversion is expected in the coil reactor as compared with that in the soaker reactor. 

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