screw expander

Abstract

In order to reduce the loss caused by the inconsistency between the internal expansion ratio and the operating expansion ratio, in the screw expander (1), there is an internal exhaust pressure detector (20), which detects that it will be connected to the exhaust flow path (9) immediately The pressure of the previous expansion space (Pf); the exhaust pressure detector (21) is operated to detect the pressure (Pd) of the exhaust flow path (9); the bypass flow path (13) enables ) and the exhaust flow path (9) isolate the expansion space from the supply flow path (8); the valve mechanism (10) can cut off the bypass flow path (13); the control device (22), when the internal When the detection value (Pf) of the exhaust pressure detection mechanism (20) is above the detection value (Pd) of the exhaust pressure detection mechanism (21) during operation, the valve mechanism (10) is blocked, and when the internal exhaust pressure detection mechanism (20) The detection value (Pf) of the exhaust pressure detection mechanism (21) is smaller than the detection value (Pd) of the operating exhaust pressure detection mechanism (21), and the valve mechanism (10) is opened.

Description

technical field [0001] The present invention relates to screw expanders. Background technique [0002] Power generation systems that drive generators by flash evaporation of water vapor have been widely introduced, but conventionally, there are many large-scale installations that use turbocharging or axial flow turbines. Recently, however, from the viewpoint of energy saving, there has been an increasing demand for small-scale power generation systems that recover exhaust heat and generate power. [0003] In small-scale facilities, it is known that, for example, it is more efficient to use a screw expander instead of a turbine as described in Non-Patent Document 1. In general, in a screw expander, the ratio of the volume at the time of air supply to the volume at the time of exhaust of the expansion space divided by the screw rotor into the rotor chamber is determined by the shape of the machine. The ratio of the pressure in the expansion space at the moment of isolation (...

AI Technical Summary

Problems solved by technology

In principle, the binary power generation system has low power generation efficiency, so it is hardly practical except for cases where there is a large-capacity heat source, although the temperature cannot cause water vapor to flash like geothermal power generation.

Therefore, in the binary power generation system, there is a problem that losses due to the above-mentioned inconsistency between the internal expansion ratio and the operating expansion ratio are likely to occur.

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