Compressors, continuous-flow

Continuous-Flow Compressors Continuous-flow compressors are machines where the flow is continuous, unlike positive displacement machines where the flow is fluctuating. Continuous-flow compressors are also classified as turbomachines. These types of machines are widely used in the chemical and petroleum industiy for many services. They are also used extensively in many other industries such as the iron and steel industry, pipeKne boosters, and on offshore platforms for reinjection compressors. Continuous-flow machines are usually much smaller in size and produce much less vibration than their counterpart, positive displacement units. 

Continuous-flow compressors. a. Centrifugal compressors h. Axial flow compressors... 

Compressors A compressor is a device that pressurizes the air in a gas turbine. It transfers energy by dynamic means from a rotating member to the continuously flowing air. The two types of compressors used in gas turbines are axial and centrifugal. Figures 29-25 and 29-26 depict typical industrial gas turbines. 

In much the same manner as pumps, compressors are classified as one of two general classes positive displacement or dynamic (see Figure 3-68) [23]. These two general classes of compressors are the same as that for pumps. The positive displacement class of compressors is an intermittent flow device, which is usually a reciprocating piston compressor or a rotary compressor (e.g., sliding vane, screws, etc.). The dynamic class of compressor is a continuous flow device, which is usually an axial-flow or centrifugal compressor (or mix of the two). 

Dynamic compressors are rotary continuous-flow machines in which the rapidly rotating element accelerates... 

Figure 8.5. Schematic view of continuous flow reaction setup for IL/scCC>2 systems (adapted from reference [81]). C compressor, CT cold trap, D dosimeter, DP depressuriser, F flowmeter, M mixer, MF metal filter, P HPLC pump, PT pressure transducer and thermocouple, R reactor, S styrene...

Air line respirators are similar to hose respirators, except that they are supplied with compressed air from a clean air source and compressor. They provide complete protection, and because they offer little in the way of breathing resistance, they are more suitable than hose respirators for prolonged use. There are two basic types continuous flow and demand flow. 

Bleeding the vapor headspace above the liquid phase reaction medium, by continuously flowing dry air into the closed vessel through the simultaneous use of a vacuum pump, to remove moist air, and a compressor, to introdnce dry air ... 

Fig. 5.7-2 Schematic view ofthe continuous flow apparatus used for the enantioselective hydrovinylation of styrene in the biphasic system [EMIM][(CF3S02)2N]. The parts are labeled as follows (alphabetically) C, Compressor CT, cold trap D, dosimeter DP, depressurizer F, flowmeter M, mixer MF, metal filter P, HPLC pump PT, pressure transducer and thermocouple R, reactor S, styrene.

Centrifugal fans, blowers, and compressors are widely used in chemical processes because they produce a continuous flow, are relatively small, and are free of vibration. Because gases are compressible, the temperature difference between the compressed gas and the feed gas is significant at even moderate compression ratios and may limit the compression ratio possible in a single stage. However, the need for multiple stages in centrifugal compressors is usually dictated instead by impellor rotation-rate limitations, which limit the compression ratio that can be achieved. 

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