Compressor multistage centrifugal

Compressors and blowers for gaseous fluorine service vary in design from multistage centrifugal compressors to diaphragm and piston types. 

Motor-driven, multistage reciprocating compressors have reportedly been the most popular choice for aeroderivatives. Motor-driven, oil-fiooded screw compressors are also used in some cases. High horsepower, multistage centrifugal compressors, similar to those used at many pipeline compressor stations, may be required for the newer heavy-duty units if the distribution pipeline pressure is insufficient (see Pipelines). Gas turbines have more stringent fuel-gas specifications in terms of cleanliness than do gas-fired boilers. Thus oil- and water-knockout systems, coalescing filters, and fine-mesh filters are used. 

The radial-flow, or centrifugal compressor is a widely used comj sor and is probably second only to the reciprocating compressor in usage in the process industries. A typical multistage centrifugal compressor can he seen in Figure 1-11. The compressor uses an impeller consisting of... 

Figure 1-11. Radial-flow horizontally split multistage centrifugal compressor. Courtesy of Nuovo Pignone)...

Figure 5-8. Diagram of a multistage centrifugal compressor with a straight-through flow path.

Sayyed, S., Aerodynamic Shop Testing Multistage Centrifugal Compressor and Predicting Gas Performance, ASME 78-PET-28, New York American Society of Mechanical Engineers, 1978,... 

Similar to multistage centrifugal pumps, centrifugal compressors, as shown in Figure 10-9, use a series of rotating impellers to impart velocity... 

Figures 12-46 illustrates the key styles of wheels for use on the rotating shafts of multistage centrifugal, single-stage compressors and fans, and axial flow compressors (to he discussed later in this chapter). The flow-handling capability of a specific impeller geometry is descrihed hy the flow coefficient, ...

Figure 12-51 A. Multistage centrifugal compressors shaft seal arrangements. (Used by permission A C Compressor Corporation.)...

Selection Guide for Multistage Centrifugal Compressors, Elliott Co., Bui. P-26 15-194-FL, pub. date not available. 

Have you ever heard a 12,000-hp, 9000-rpm, multistage centrifugal compressor go into surge The periodic, deep-throated roar, emitted by the surging compressor, is just plain scary. Machines, quite obviously, are not intended to make such sounds. But what causes surge ... 

Raw gas from the quench tower is compressed in a multistage centrifugal compressor (5) to greater than 500 psig. 

Davis, H., "Evaluating Multistage Centrifugal Compressors", Chemical Engineering,... 

Compressors and pumps share a common set of operating principles. The dynamic and positive displacement families share common categories. Therefore, the symbols for compressors may closely resemble those for pumps. In most cases, the symbol Is slightly larger In the compressor symbol file. For a multistage, centrifugal compressor, the symbol clearly describes how the gas is... 

Figure 9.7 Methods of pressure generation (a,b) reciprocating pumps/compressors, (c) multistage centrifugal pumps, (d) Pulsations in volume flow produced by above pumps.

A rotor assembly of a multistage centrifugal compressor consists of the impellers, shaft sleeves (before each impellers), a balancing drum (at discharge end of shaft) with balance line ftom it to suction, and a thrust disc mowted on the suction end of the shaft. 

Stationary parts of a multistage centrifugal compressor include inlet guide vane, diaphragms, and casing. They form the various gas passages in a compressor inlet channel, diffusers, return bends, return channels, and discharge volute. 

Five principal drivers are used for multistage centrifugal compressors. These include condensing turbines, topping turbines, electric motors, gas turbines, and steam turbines. Electric motor drives generally are used in regions where cheap power is available. Steam turbines are usually inexpensive to operate and can provide up to 18,000 rpm. Condensation turbines usually run at lower speeds of between 10,000 to 14,000 rpm, while gas turbines tend to be the most expensive to operate and usually run in the range of 5,000-6,000 rpm. 

The unit has virtually the same flow sheet (see Fig. 2) as that of methanol carbonylation to acetic acid (qv). Any water present in the methyl acetate feed is destroyed by recycle anhydride. Water impairs the catalyst. Carbonylation occurs in a sparged reactor, fitted with baffles to diminish entrainment of the catalyst-rich Hquid. Carbon monoxide is introduced at about 15—18 MPa from centrifugal, multistage compressors. Gaseous dimethyl ether from the reactor is recycled with the CO and occasional injections of methyl iodide and methyl acetate may be introduced. Near the end of the life of a catalyst charge, additional rhodium chloride, with or without a ligand, can be put into the system to increase anhydride production based on net noble metal introduced. The reaction is exothermic, thus no heat need be added and surplus heat can be recovered as low pressure steam. 

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