Exhaust heat recovery system, energy supply system, and exhaust heat recovery method

Abstract

The object of the present invention is to enhance available energy recovery efficiency compared to an exhaust heat recovery method by generation of water vapor. In order to achieve this object, the present invention adopts a configuration including a thermal conduction path ( 1 ) which conducts exhaust heat, and a high-boiling-point heat medium vapor generator ( 2 ) which generates high-boiling-point heat medium vapor (R 2 ) by heat exchange between the exhaust heat which is conducted through the thermal conduction path ( 1 ) and a high-boiling-point heat medium (R 1 ) that has a higher evaporation temperature than water (R 3 ).

1 . An exhaust recovery system, comprising:
 a thermal conduction path which conducts exhaust heat; and   a high-boiling-point heat medium vapor generator which generates high-boiling-point heat medium vapor by heat exchange between a high-boiling-point heat medium that has a higher evaporation temperature than water and the exhaust heat conducted through the thermal conduction path.   
     
     
         2 . The exhaust heat recovery system according to  claim 1 , further comprising a water vapor generator which is provided in the thermal conduction path on the downstream side of the high-boiling-point heat medium vapor generator, and which generates water vapor by heat exchange between the water and the exhaust heat. 
     
     
         3 . The exhaust heat recovery system according to  claim 1 , further comprising, on the upstream side of the high-boiling-point heat medium vapor generator in the thermal conduction path, either one or both of a high-boiling-point heat medium vapor superheater which superheats the high-boiling-point heat medium vapor by heat exchange with the exhaust heat, or a water vapor superheater which superheats the water vapor by heat exchange with the exhaust heat. 
     
     
         4 . The exhaust heat recovery system according to  claim 1 , further comprising a high-boiling-point heat medium preheater which preheats the high-boiling-point heat medium and/or a water preheater which preheats the water. 
     
     
         5 . The exhaust heat recovery system according to  claim 1 , wherein the thermal conduction path is an exhaust gas pipe through which exhaust gas possessing the exhaust heat flows. 
     
     
         6 . The exhaust heat recovery system according to  claim 1 , wherein the high-boiling-point heat medium is ethylene glycol, diethylene glycol, propylene glycol, propylene ethylene glycol, or formamide. 
     
     
         7 . The exhaust heat recovery system according to  claim 4 , wherein, instead of the water vapor generator, a flash type water vapor generator which converts the water preheated in the water preheater to the water vapor by the flash phenomenon is provided. 
     
     
         8 . An energy supply system, comprising:
 the exhaust heat recovery system according to  claim 1 ;   and a dynamic force generation unit which supplies the high-boiling-point heat medium and/or the water to the exhaust heat recovery system, recovers the high-boiling-point heat medium vapor and/or the water vapor from the exhaust heat recovery system, and generates dynamic force using the high-boiling-point heat medium vapor and/or the water vapor as working fluid.   
     
     
         9 . The energy supply system according to  claim 8 , wherein the dynamic force generation unit includes a heat exchanger which carries out heat exchange between the water and the high-boiling-point heat medium vapor after being provided for generation of the dynamic force to condense and liquefy the high-boiling-point heat medium vapor, and to generate the water vapor. 
     
     
         10 . An exhaust heat recovery method, which performs heat recovery by vaporizing a high-boiling-point heat medium having a higher evaporation temperature than water by exhaust heat. 
     
     
         11 . The exhaust heat recovery method according to  claim 10 , wherein heat recovery is performed by vaporizing water by the exhaust heat after heat recovery using the high-boiling-point heat medium. 
     
     
         12 . The exhaust heat recovery method according to  claim 10 , wherein high-boiling-point heat medium vapor and/or water vapor are superheated by heat exchange with the exhaust heat. 
     
     
         13 . The exhaust heat recovery method according to  claim 10 , wherein the high-boiling-point heat medium is ethylene glycol, diethylene glycol, propylene glycol, propylene ethylene glycol, or formamide. 
     
     
         14 . The exhaust heat recovery method according to  claim 11 , wherein, instead of performing heat recovery by vaporizing the water by the exhaust heat after heat recovery using the high-boiling-point heat medium, heat recovery is preformed by preheating the water by the exhaust heat after heat recovery using the high-boiling-point heat medium, and then vaporizing the preheated water by the flash phenomenon.