Process and device for the recovery of energy

Abstract

The invention relates to a process and device for the recovery of energy from the waste heat of thermal or chemical processes, wherein at least a portion of said waste heat evaporates a liquid via at least one heat transfer means or heats a vapour or a gas, increasing the pressure thereof, and this pressure is transformed into mechanical energy in an engine ( FIG. 1 ).

1 . A process for the recovery of energy from the waste heat of a combustion engine comprising an exhaust gas recirculation, in particular of a mobile combustion engine, characterized in that at least a portion of the waste heat of the recycled exhaust gas evaporates a liquid and/or heats a vapour and/or a gas, increasing the pressure thereof, and this pressure is transformed into mechanical energy in an engine.  
   
   
       2 . A process for the recovery of energy from the waste heat of a combustion engine, in particular of a mobile combustion engine, and of a fuel cell, characterized in that at least a portion of the waste heat of the exhaust gas of the combustion engine, in particular of a recycled exhaust gas, and at least a portion of the waste heat of the fuel cell evaporate a liquid and/or heat a vapour and/or a gas, increasing the pressure thereof, and this pressure is transformed into mechanical energy in an engine.  
   
   
       3 . A process according to  claim 1 , characterized in that the vapour or gas is evaporated or heated, respectively, in two or more stages.  
   
   
       4 . A process according to  claim 1 , characterized in that the conversion into mechanical energy is carried out via a steam turbine.  
   
   
       5 . A process according to  claim 1 , characterized in that the conversion into mechanical energy is carried out via a gas turbine.  
   
   
       6 . A process according  claim 1 , characterized in that the conversion into mechanical energy is carried out via a piston engine.  
   
   
       7 . A process according to  claim 1 , characterized in that at least one heat transfer stage is a heat pump.  
   
   
       8 . A process according to  claim 1  characterized in that, in front of the engine, energy is stored in an energy store.  
   
   
       9 . A process according to  claim 1 , characterized in that the mechanical energy is used as an auxiliary energy for the combustion engine and/or for the fuel cell and/or as an auxiliary energy in means of transport such as vehicles, preferably for driving a coolant pump and/or a hydraulic unit and/or a compressor for an air-conditioning system.  
   
   
       10 . A process according to  claim 1 , characterized in that the mechanical energy is transformed into electrical energy.  
   
   
       11 . A process according to  claim 10 , characterized in that the electrical energy is used as an auxiliary energy for the combustion engine and/or for the fuel cell and/or as an auxiliary energy in vehicles, preferably for driving a coolant pump and/or a hydraulic unit and/or a compressor for an air-conditioning system.  
   
   
       12 . A process according to  claim 1 , characterized by an exhaust gas turbine of the combustion engine, wherein exhaust gas to be recycled is branched off before the exhaust gas is introduced into the exhaust gas turbine.  
   
   
       13 . A process according to  claim 12 , characterized in that at least a portion of the waste heat of the exhaust gas expanded in the exhaust gas turbine evaporates a liquid and/or heats a vapour and/or a gas, increasing the pressure thereof, and this pressure is transformed into mechanical energy in an engine.  
   
   
       14 . A process according to  claim 12 , characterized in that the liquid or the vapour or the gas, respectively, heated by the expanded exhaust gas, is heated further, in particular superheated, by the exhaust gas to be recycled.  
   
   
       15 . A process according to  claim 12 , characterized in that the liquid or the vapour or the gas, respectively, heated by the expanded exhaust gas, is mixed with the liquid or the vapour or the gas, respectively, heated by the recycled exhaust gas.  
   
   
       16 . A process according to  claim 2 , characterized in that a liquid or a vapour or a gas, respectively, heated by the waste heat of the fuel cell is mixed with a liquid or a vapour or a gas, respectively, heated by the exhaust gas of the combustion engine.  
   
   
       17 . A device for the recovery of energy from the waste heat of a combustion engine comprising an exhaust gas recirculation, in particular of a mobile combustion engine, characterized by the combination of the following features: 
 at least one heat transfer means for transferring the thermal energy of the recycled exhaust gas to a heat carrier medium,    a device for increasing the pressure of the heat carrier medium,    an engine, preferably a steam turbine, which transforms the energy stored in the heat carrier medium into mechanical energy.    
   
   
       18 . A device for the recovery of energy from the waste heat of a combustion engine, in particular of a mobile combustion engine, and of a fuel cell, characterized by the combination of the following features: 
 at least one heat transfer means for transferring the thermal energy of the exhaust gas of the combustion engine to a heat carrier medium,    at least one heat transfer means for transferring the thermal energy of the fuel cell to a heat carrier medium,    a device for increasing the pressure of the heat carrier medium,    an engine, preferably a steam turbine, which transforms the energy stored in the heat carrier medium into mechanical energy.    
   
   
       19 . A device according to  claim 17 , characterized by two or more heat transfer means which gradually heat the heat carrier medium.  
   
   
       20 . A device according to  claim 17 , characterized in that the heat carrier medium is identical with the cooling medium for the combustion engine and/or the fuel cell.  
   
   
       21 . A device according to  claim 17 , characterized in that at least one heat transfer means is a heat pump.  
   
   
       22 . A device according to  claim 17 , characterized in that an energy store is arranged in front of the engine.  
   
   
       23 . A device according to  claim 17 , characterized in that the engine is coupled with at least one drive for at least one auxiliary power unit for the thermal or chemical process, preferably cooling or lubricant pumps.  
   
   
       24 . A device according to  claim 17 , characterized in that the engine is coupled with at least one drive for at least one auxiliary power unit for a vehicle, preferably with the drive of a hydraulic unit and/or a compressor for an air-conditioning system  
   
   
       25 . A device according to  claim 17 , comprising an electric power generator, preferably a generator, which is drivable by the engine and transforms at least a portion of the mechanical energy into electrical energy.  
   
   
       26 . A device according to  claim 25 , characterized in that the electrical energy is provided for the operation of auxiliary power units for the combustion engine and/or the fuel cell, preferably of cooling or lubricant pumps.  
   
   
       27 . A device according to  claim 25 , characterized in that the electrical energy is provided for the operation of auxiliary power units for a vehicle, preferably of a hydraulic unit and/or a compressor for an air-conditioning system.  
   
   
       28 . A device according to  claim 17 , characterized by an exhaust gas turbine of the combustion engine, wherein an exhaust-gas branch duct for exhaust gas to be recycled, which branches off—in the flow direction of the exhaust gas—from the exhaust gas duct in front of the exhaust gas turbine, runs into a heat transfer means.  
   
   
       29 . A device according to  claim 28 , characterized in that a heat transfer means for exhaust gas expanded in the exhaust gas turbine is arranged downstream of the exhaust gas turbine.  
   
   
       30 . A device according to  claim 28 , characterized in that a heat carrier medium duct runs from the heat transfer means arranged downstream of the exhaust gas turbine to the heat transfer means for the exhaust gas to be recycled.  
   
   
       31 . A device according to  claim 28 , characterized in that a mixing device for the heat carrier medium heated by the exhaust gas to be recycled and the heat carrier medium heated by the remaining exhaust gas is provided.  
   
   
       32 . A device according to  claim 28 , characterized in that a heat carrier medium heated by the fuel cell can be supplied via a duct to a mixing device for mixing with a heat carrier medium heated by the exhaust gas of the combustion engine.