Falling film evaporator for power generation systems

Abstract

A system ( 10 ) includes a condenser ( 12 ) with an inlet ( 22 ) and an outlet ( 24 ), a pump ( 14 ) with an outlet ( 28 ) and with an inlet ( 26 ) connected to the outlet ( 24 ) of the condenser ( 12 ), and an evaporator ( 16 ). The evaporator ( 16 ) includes an inlet ( 30 ) connected to the outlet ( 28 ) of the pump ( 14 ), an outlet ( 31 ), evaporating tubes ( 38 ), and a fluid distribution system ( 33 ) for spraying a fluid over the evaporating tubes ( 38 ). The system ( 10 ) further includes a turbine ( 18 ) with an inlet ( 44 ) connected to the outlet ( 31 ) of the evaporator ( 16 ), an outlet ( 48 ) connected to the inlet ( 22 ) of the condenser ( 12 ), and a drive shaft ( 46 ). A generator ( 20 ) is connected to the drive shaft ( 46 ) of the turbine ( 18 ).

1 . A system comprising:
 a condenser with an inlet and an outlet;   a pump with an outlet and with an inlet connected to the outlet of the condenser;   an evaporator comprising:
 an inlet connected to the outlet of the pump; 
 an outlet; 
 a plurality of evaporating tubes; and 
 a fluid distribution system for spraying a fluid over the plurality of evaporating tubes; 
   a turbine with an inlet connected to the outlet of the evaporator, an outlet connected to the inlet of the condenser, and a drive shaft; and   a generator connected to the drive shaft of the turbine.   
     
     
         2 . The system of  claim 1 , wherein the system is a power generation system. 
     
     
         3 . The system of  claim 1 , wherein the fluid is a refrigerant. 
     
     
         4 . The system of  claim 3 , wherein the refrigerant is a hydrofluorocarbon, hydrocarbon, fluorinated ketone, fluorinated ether, chloro-olefin, bromo-fluoro olefin, hydrofluoroolefin, hydrofluoroolefin ether, hydrochlorofluoroolefin ether, linear siloxane, or cyclic siloxane. 
     
     
         5 . The system of  claim 4 , wherein the refrigerant is propane, cyclopropane, isobutene, isobutane, n-butane, propylene, n-pentane, isopentane, cyclopentane, R-134a, R-30, R-32, R-123, R-125, R-143a, R-134, R-152a, R-161, R-1216, R-227ea, R-245fa, R-245cb, R-236ea, R-236fa, R-365mfc, HT-55, R-43-10mee, HFE-7100, Novec-649, CF3I, R-1234ye, R-1234yf, R-1234ze, R-1233zd(E), R-1233zd(Z), R-1225ye(Z), R-1225ye(E), C5F9Cl, C5H2F10, R-1243zf, E-134a, E134, E125, E143a, siloxane MM, dimethylether, or CO2. 
     
     
         6 . The system of  claim 1 , wherein the evaporator further comprises pool boiling tubes. 
     
     
         7 . The system of  claim 6 , wherein the evaporator further comprises a plurality of superheating tubes near the outlet of the evaporator for heating the fluid evaporated by the plurality of evaporating tubes and the plurality of pool boiling tubes. 
     
     
         8 . The system of  claim 7 , wherein the plurality of superheating tubes is next to the plurality of evaporating tubes below the fluid distribution system. 
     
     
         9 . The system of  claim 7 , wherein the plurality of superheating tubes is above the fluid distribution system. 
     
     
         10 . The system of  claim 1 , and further comprising a recirculation pump for recirculating fluid from the evaporator to the inlet of the evaporator. 
     
     
         11 . The system of  claim 10 , wherein the evaporator further comprises a plurality of superheating tubes near the outlet of the evaporator for heating the fluid evaporated by the plurality of evaporating tubes and the plurality of pool boiling tubes. 
     
     
         12 . The system of  claim 11 , wherein the plurality of superheating tubes is next to the plurality of evaporating tubes below the fluid distribution system. 
     
     
         13 . The system of  claim 12 , wherein the plurality of superheating tubes is above the fluid distribution system. 
     
     
         14 . A method of processing a fluid in a system, the method comprising:
 condensing the fluid in a condenser;   pumping the fluid from the condenser into an evaporator;   spraying the fluid from a fluid distribution system in the evaporator to cover a plurality of evaporating tubes in the evaporator;   dripping an excess of the fluid off of the plurality of evaporating tubes to form a pool in the evaporator;   evaporating the fluid from the plurality of evaporating tubes;   expanding the evaporated fluid in a turbine; and   producing power in a generator using the fluid expanded in the turbine.   
     
     
         15 . The method of  claim 14 , wherein the fluid is a refrigerant. 
     
     
         16 . The method of  claim 15 , wherein the refrigerant is a hydrofluorocarbon, hydrocarbon, fluorinated ketone, fluorinated ether, chloro-olefin, bromo-fluoro olefin, hydrofluoroolefin, hydrofluoroolefin ether, hydrochlorofluoroolefin ether, linear siloxane, or cyclic siloxane. 
     
     
         17 . The method of  claim 16 , wherein the refrigerant is propane, cyclopropane, isobutene, isobutane, n-butane, propylene, n-pentane, isopentane, cyclopentane, R-134a, R-30, R-32, R-123, R-125, R-143a, R-134, R-152a, R-161, R-1216, R-227ea, R-245fa, R-245cb, R-236ea, R-236fa, R-365mfc, HT-55, R-43-10mee, HFE-7100, Novec-649, CF3I, R-1234ye, R-1234yf, R-1234ze, R-1233zd(E), R-1233zd(Z), R-1225ye(Z), R-1225ye(E), C5F9Cl, C5H2F10, R-1243zf, E-134a, E134, E125, E143a, siloxane MM, dimethylether, or CO2. 
     
     
         18 . The method of  claim 14 , wherein evaporating the fluid further comprises evaporating the fluid from the pool with a plurality of pool boiling tubes. 
     
     
         19 . The method of  claim 18 , and further comprising heating the evaporated fluid with a plurality of superheating tubes prior to expanding the evaporated fluid in the turbine. 
     
     
         20 . The method of  claim 14 , and further comprising recirculating the fluid from the pool in the evaporator back to the fluid distribution system of the evaporator. 
     
     
         21 . The method of  claim 20 , and further comprising heating the evaporated fluid with a plurality of superheating tubes prior to expanding the evaporated fluid in the turbine. 
     
     
         22 . The method of  claim 14 , wherein the excess of fluid dripping off of the plurality of evaporating tubes comprises between 15 and 25 percent of the fluid sprayed from the fluid distribution system.