Compressors configuration

Compressor Configuration To propeny design a centrifugal compressor, one must know the operating conditions—the type of gas, its pressure, temperature, and molecular weight. One must also know the corrosive properties of the gas so that proper metallurgical selection can be made. Gas fluctuations due to process instabilities must be pinpointed so that the compressor can operate without surging. 

The rotary compressor portion of the positive displacement family is made up of several compressor configurations. The features these compressors have in common are ... 

Several heat exchanger and compressor configurations were considered, since the thermal integration of the system has a significant impact on the efficiency. An optimal process configuration was selected, and the process flow diagrams were developed. As shown in Table 1, the efficiency of the optimal configuration is 75.2%. Compressor calculations showed that electricity required was... 

When conplete sentences are separated by conjunctive adverbs (therefore, however, although), the conjunctive adverb is preceded by a semicolon and followed by a comma (for exanple, A three-compressor configuration was investigated however, the two-conpressor configuration was found to be the optimum ). 

Figure 13.10 Indicator diagrams of a piston pump and a piston compressor configuration for a realistic application toward 30MPa Vd detrimental space Vs stroke volume source Institute of Process Machinery and Systems Engineering, University of Erlangen-Nuremberg, Germany).

Sometimes it is extremely difficult to avoid vapor recycles without using very high pressures or very low levels of refrigeration, in which case we must accept the expense of a recycle compressor. However, when synthesizing the separation and recycle configuration, vapor recycles should be avoided, if possible, and liquid recycles used instead. 

The axial flow compressors in aero gas turbines are heavily loaded. The aspecl ratio of the blades, especially the first few stages, can be as high as 4.0, and the effecl of streamhne curvature is substantial. The streamline configuration is a function of the annular passage area, the camber and thickness distribution of the blade, and the flow angles at the inlet and outlet of the blades. The shafts on these units are supported on antifriction bearings (roller or ball bearings). 

The surge protection described above is for a simple, single section, constant geometry compressor with constant inlet conditions and constant speed of rotation. Many compressor installations involve more complex configurations and applications. 

Compressors have numerous forms, the exact configuration being based on the application. For comparison, the different types of compressors can be subdivided into two broad groups based on compression mode. There are two basic modes intermittent and continuous. The intermittent mode of compression is cyclic in nature, in that a specific quantity of gas IS ingested by the compressor, acted upon, and discharged, before the cycle is repeated. The continuous compression mode is one in which the gas is moved into the compressor, is acted upon, moved through the compressor, and discharged without interruption of the tlnv. at any point in the process. 

Centrifugal compressors range in volumetric size from approximately 1,(X)0 to 150,000 cfm. In single-wheel configuration, pressures vary considerably. A common low pressure compressor may only be capable of 10 to 12 psi discharge pressure. In higher-head models, pressure ratios of 3 are available, which on air is a 30-psi discharge pressure when the inlet is at atmospheric conditions. 

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