Self-overlapping type solar low temperature ranking cycle system

Abstract

The invention discloses an auto-cascade solar energy low-temperature Rankine cycle system, which respectively does work on two stages of steam turbines in an expanding way by utilizing the characteristics of non-azeotropic binary working medium when changing phase. A solar thermal collector is connected with a gas-liquid separator, a first stage steam turbine is connected with the upper part of the gas-liquid separator, the exit end of the first stage steam turbine is connected with the low-voltage entrance side of an external heat exchanger, while the low-voltage exit side is connected between a working medium pump and the solar thermal collector. The fluid outlet end of the gas-liquid separator is connected with the high-voltage entrance side of the external heat exchanger, while the high-voltage exit side of the external heat exchanger is connected with the entrance of a second stage steam turbine, and the exit end of the steam turbine is connected with a condenser which is connected with the working medium pump. The steam turbines are respectively provided with a generator. According to the characteristics of the selected working medium, the steam turbine can be replaced by an expander. Compared with the conventional low-temperature Rankine cycle, the system has the advantages of high cycle efficiency, no added working fluid recycle pump and heat-exchange equipment, saves the area of the solar thermal collector in the low-temperature Rankine cycle system, and reduces the system cost.

Description

technical field [0001] The invention belongs to solar thermal power generation equipment, in particular to a self-cascading solar low-temperature Rankine cycle system. Background technique [0002] The solar low-temperature Lang cycle system can use conventional solar collectors, heat exchangers, working medium pumps, small expanders or steam turbines, generators and other equipment to realize the conversion of solar energy into mechanical energy or electrical energy. The current development direction of solar low-temperature Rankine cycle technology is to improve the efficiency of the system and reduce the cost of the system. Therefore, the current research on the low-temperature solar Rankine cycle mainly focuses on the selection of suitable working fluid for the Rankine cycle and the optimal design of the circulation system. The solar low-temperature Rankine cycle system currently in use mainly uses a single-stage Rankine cycle with pure working fluid. circulatory system...

AI Technical Summary

Problems solved by technology

The working fluid directly enters the condenser (air-cooled or water-cooled) for condensation after a primary expansion, and a large amount of condensation heat is directly discharged into the environment, and the thermal efficiency of the system is low

At the same time, because the heat of the working medium comes from solar radiation, the discharged and unused condensation heat actually increases the use area of ​​the solar collector of the system, which increases the cost of the system and reduces the economy of the system

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