Working fluid for rankine cycle

Abstract

An organic Rankine cycle working fluid comprising at least one compound having formula (I): RNQ, wherein R is fluorinated or non-fluorinated methyl, ethyl, vinyl or ethynyl, N is element nitrogen, the connection of R—N is a ring structure or a straight chain structure, and Q is a hydrogen and/or at least one fluorine atom. A process for converting thermal energy into mechanical energy, a method for power generation, an organic Rankine cycle system, and the use of the working fluid for heat transfer or in a mechanical power generation device are also provided. The organic Rankine cycle working fluid has a high energy conversion efficiency, low flammability, low toxicity and low corrosion on copper.

1 . An organic Rankine cycle working fluid comprising at least one compound having a structure according to Formula (I):
   RNQ   wherein   R is fluorinated or non-fluorinated methyl, ethyl, vinyl, or ethynyl,   N is the element nitrogen,   the connection of R—N is a ring structure or a straight chain structure, and   Q is chosen from a hydrogen atom and/or at least one fluorine atom.   
     
     
         2 . An organic Rankine cycle working fluid according to  claim 1 , said at least one compound is either of the Formula (II):
   R 1 NH n F 2-n .   wherein   R 1  is fluorinated or non-fluorinated methyl, ethyl, vinyl, or ethynyl, and   n is 0 or 1;   or   the Formula (III):   
       
         
           
           
               
               
           
         
         wherein 
         R 2  and R 3  are independently chosen from H 2 , F 2  and HF, and 
         p is 0 or 1. 
       
     
     
         3 . A working fluid according to  claim 2 , wherein R 1  in Formula (II) is a fluorinated or non-fluorinated methyl or ethyl group. 
     
     
         4 . A working fluid according to  claim 3 , wherein said compound is chosen from CH 3 NHF, CH 2 FNHF, CHF 2 NHF, CF 3 NHF, CH 3 NF 2 , CH 2 FNF 2 , CHF 2 NF 2 , CF 3 NF 2 , C 2 H 5 NHF, CH 2 FCH 2 NHF, CHF 2 CH 2 NHF, CH 3 CHFNHF, CH 2 FCHFNHF, C 2 H 5 NF 2 , CH 2 FCH 2 NF 2 , CH 3 CHFNF 2 , and CHF 2 CF 2 NF 2 . 
     
     
         5 . A working fluid according to  claim 4 , wherein said compound is chosen from CH 3 NF 2 , CH 2 FNF 2 , CHF 2 NF 2 , and CF 3 NF 2 . 
     
     
         6 . A working fluid according to  claim 2 , wherein p in Formula (II) is 1. 
     
     
         7 . A working fluid according to  claim 6 , wherein R 2  in Formula (II) contains at least one fluorine. 
     
     
         8 . A working fluid according to  claim 7 , wherein said compound is tetrafluoroaziridine. 
     
     
         9 . A process for converting thermal energy to mechanical energy in an organic Rankine cycle comprising the steps of:
 a) vaporizing a liquid working fluid according to  claim 1 , by bringing it in contact with a heat source;   b) expanding the vaporized working fluid, wherein said heat is converted into mechanical work; and   c) cooling the expanded vaporized working fluid with a cooling source to condense the vapor to liquid phase.   
     
     
         10 . A process according to  claim 9 , wherein the temperature of the work fluid after being brought in contact with a heat source in a) is at most 100° C. 
     
     
         11 . A process according to  claim 10 , wherein said temperature is 25° C. to 90° C. 
     
     
         12 . An organic Rankine cycle system using the working fluid according to  claim 1  for a heat cycle. 
     
     
         13 . An organic Rankine cycle system comprising:
 (a) a working fluid according to  claim 1 ; (b) a heat exchanging device containing said working fluid, connected to a heat source, for vaporizing the working fluid and producing vaporized working fluid; (c) an expansion device responsive to said vaporized working fluid for expanding said working fluid vapor resulting in heat depleted working fluid; (d) an electric generator driven by said expansion device for producing electrical power; (e) a condenser for condensing the heat depleted working fluid and producing condensate; and (f) means for effecting the return of said condensate to said heat exchanging device.   
     
     
         14 . An organic Rankine cycle system according to  claim 13 , wherein the heat source is chosen from heat from a boiler or a fuel cell, waste heat from an industrial or farming process, geothermal heat, waste heat from a combustion engine or power plant, or solar heat. 
     
     
         15 . An organic Rankine cycle system according to  claim 13 , wherein the expander is a turbine, screw expander, scroll expander, or piston expander. 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . A method for power generation comprising transfer of heat using a working fluid according to  claim 1 . 
     
     
         19 . A method for power generation according to  claim 1 , using a Rankine cycle or a modification thereof to generate work from heat. 
     
     
         20 . A compound having the Formula (IV):