Multilevel solar energy middle and low temperature Rankine cycle system

Abstract

The invention discloses a multistage solar power medium and low temperature Rankine cycle system, which is composed of two or more stages of solar power Rankine cycle systems. Each stage of the Rankine cycle system is composed of basic components such as a solar energy collector, an expander or a steam turbine, a generator, an internal heat exchanger, a fluid reservoir, a working fluid pump and so on. Two adjacent stages of the Rankine cycle systems are connected through an external heat exchanger. Backheating occurs between the working fluid dead steam in the internal heat exchanger and the working fluid of the same stage. In the external heat exchanger, high temperature level working fluid exchanges heat with the low temperature working fluid. The condensation heat of the high temperature level working fluid becomes an evaporation heat source of the lower temperature level working fluid partially. By adopting the internal heat exchanger and the external heat exchanger, not only the efficiency of the Rankine cycle system is improved, but also the area of the solar collector in the low temperature level Rankine cycle system is reduced, thus reducing the cost of the system.

Description

technical field [0001] The invention belongs to solar thermal power generation equipment, in particular to a system of multi-stage solar medium and low temperature Rankine cycles. Background technique [0002] The solar medium and low temperature Lang cycle system can use conventional solar collectors, heat exchangers, working medium pumps, small expanders (or steam turbines), generators and other industrial equipment to realize the conversion of solar energy into mechanical energy or electrical energy. At present, the 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 medium and low temperature solar Rankine cycle mainly focuses on the selection of suitable working fluid for the Rankine cycle and the design of the cycle system. The solar low-temperature Rankine cycle systems currently in use are all single-stage Rankine cycle systems usi...

AI Technical Summary

Problems solved by technology

The working medium exhaust steam discharged from the expander or steam turbine directly enters the condenser (air-cooled or water-cooled) for condensation, 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

Images