Passive low temperature heat sources organic working fluid power generation method

Abstract

The present invention relates to a passive type low-temperature heat sources organic working fluid power generation method. The organic working fluid absorbs heat and evaporates in the first evaporator and the second in turn evaporator. When the pressure of organic working fluid reaches the set pressure, the self-operated pressure regulator valve at the outlet of the evaporator opens triggered by operating pressure. The organic working fluid vapor flows into the turbine and pushes the turbine to rotate with a high speed, driving the generator to provide output power. The low-temperature low-pressure exhaust gas flows into the condenser and condenses into liquid working fluid. Through the first and second evaporator in turn providing working steam, the turbine can maintain continuous work and provide output power. Compared with the prior technology, the present invention has reliable performance, relying on the evaporation of the working fluid in a closed space to achieve increased pressure.

We claim: 
     
         1 . A method of the passive type low-temperature heat sources organic working fluid generation method comprises the steps of:
 (1) when the organic working fluid within the first evaporator absorbs heat and evaporates, the temperature and the pressure of first evaporator increases until the organic working fluid pressure reaches the set pressure. The first self-operated pressure regulator valve at the outlet of the first evaporator opens triggered by working pressure, the organic working fluid vapor flows into the turbine and pushes the turbine to rotate with a high speed, driving the generator to provide output power. The low-temperature low-pressure exhaust gas flows into the condenser and condenses into liquid working fluid;   (2) The condensed organic working fluid flows into the reservoir. As the organic working fluid of the first evaporator consuming, the evaporator pressure drops to the set value of self-operated pressure regulator valve, and the first self-operated pressure regulator valve and the fifth self-operated pressure regulator valve automatically shuts down. The second self-operated pressure regulator valve opens automatically by gravity, and the organic working fluid in reservoir flows into the first evaporator. After a period of time, the second self-operated pressure regulator valve is closed again and the fifth self-operated pressure regulator valve is open. The organic working fluid within the first evaporator is heated for the next cycle;   (3) when the first evaporator is refilled with liquid working fluid, the second evaporator's working fluid is heated to the set pressure and the third self-operated pressure regulator valve automatically opens, replacing the first evaporator to provide continuous working steam to drive turbine and generator for output power. The refrigerant refilling method of the second evaporator is the same as the first evaporator. When the third self-operated pressure regulator valve and the fifth self-operated pressure regulator valve closes automatically, the fourth self-operated pressure regulator valve automatically opens. The organic working fluid from the reservoir flows into the second evaporator by gravity. After refilling process, the fourth self-operated pressure regulator valve closes automatically and the fifth self-operated pressure regulator valve automatically open;   (4) The second evaporator is refilled with organic working fluid and heated to the working point. During this period, according to the system design, the pressure of the working fluid of first evaporator has reached to the set value. The first evaporator can replace of the second evaporator for the output working steam. The first evaporator and the second evaporator in turn provide continuous working steam to drive turbine and generator for continuous output power.   
     
     
         2 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said organic working fluid is pure or mixture of R245fa, R600, R600a, R141b or R142b. 
     
     
         3 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said organic working fluid in the first evaporator is heated and evaporated. The temperature can reached 60° C.-180° C. The pressure reaches the set pressure of 0.5 MPa-5 MPa. 
     
     
         4 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said organic working fluid in the second evaporator is heated and evaporated. The temperature can reached 60° C.-180° C. The pressure reaches the set pressure of 0.5 MPa-5 MPa. 
     
     
         5 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , characterized in that: wherein said temperature of the steam at the inlet of turbine is 60° C.-180° C., with the pressure of 0.5 MPa-5 MPa. 
     
     
         6 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said outlet pressure of turbine is 0.2 MPa-1.0 MPa and the outlet temperature of turbine is 30° C.-120° C. 
     
     
         7 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said position of reservoir is 200-2000 mm higher than that of the first evaporator and the second evaporator, in order to use the gravitational potential for the transmission of liquid working fluid. 
     
     
         8 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said heat source for evaporator can be geothermal energy, solar energy or industrial waste heat. The heat source temperature ranges from 85 to 200° C. 
     
     
         9 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that: wherein said cold source for condenser is groundwater, river water, sea water or air. The cold source temperature is 0-40° C. 
     
     
         10 . The passive type low-temperature heat sources organic working fluid power generation method as set forth in  claim 1 , is characterized in that, wherein said the turbine expansion ratio range from 1.5 to 15.