Thermal power station

Abstract

The invention relates to a thermal power station and a method for storing heat by means of a steam generator a water-steam cycle which is connected to the steam generator and to a thermal store. Said thermal store comprises a first container for a heat store medium when it is cold, a second container for the heat store medium when it is hot, and a heat exchanger which is connected to the two containers and which is connected to the heat-steam cycle via a water-steam feed line and a water-steam discharge line. The thermal store has an additional heat exchanger which is connected to the two containers, an air feed line and an air discharge line being provided, the air discharge line being connected to the combustion air feed line leading to the combustion chamber.

1 . A thermal power station having a steam generator, which comprises a combustion chamber with a feed for combustion air, having a water-steam cycle, which is connected to the steam generator, and having a thermal store, which is connected to the water-steam cycle, wherein the thermal store comprises a first container for a heat store medium when it is cold, a second container for the heat store medium when it is hot, and a heat exchanger which is connected to the first container and to the second container, wherein the heat exchanger is connected to the water-steam cycle via a water-steam feed line and a water-steam discharge line, wherein the heat store medium can be conveyed from the first container via the heat exchanger to the second container in order to absorb heat from the water and steam, wherein the thermal store comprises an additional heat exchanger which is connected to the first container and to the second container, wherein an air feed line for feeding air into the additional heat exchanger and an air discharge line for discharging the air from the additional heat exchanger are provided, wherein the heat store medium can be conveyed from the second container via the additional heat exchanger to the first container in order to dissipate heat to the air, wherein the air discharge line is connected to the feed for combustion air into the combustion chamber. 
     
     
         2 . The thermal power station according to  claim 1 , wherein a first shut-off device is provided between the first container and the heat exchanger and/or a second shut-off device is provided between the first container and the additional heat exchanger and/or a third shut-off device is provided between the second container and the heat exchanger and/or a fourth shut-off device is provided between the second container and the additional heat exchanger. 
     
     
         3 . The thermal power station according to  claim 1 , wherein solid particles, including sand or corundum, are arranged as heat store medium in the first and/or second container. 
     
     
         4 . The thermal power station according to  claim 1 , wherein a fluidised bed heat exchanger is provided each as the heat exchanger and/or as the additional heat exchanger. 
     
     
         5 . The thermal power station according to  claim 1 , wherein air preheater for preheating the combustion air for the combustion chamber is provided. 
     
     
         6 . The thermal power station according to  claim 5 , wherein the air feed line for the additional heat exchanger is branched from a connection line between the air preheater and the combustion chamber. 
     
     
         7 . The thermal power station according to  claim 5 , wherein the air preheater is connected to a fresh air inlet, wherein the air feed line for the additional heat exchanger is connected to a fluidisation air inlet. 
     
     
         8 . The thermal power station according to  claim 7 , wherein the fresh air inlet is connected to a fresh air fan and/or the fluidisation air inlet is connected to a fluidisation fan. 
     
     
         9 . The thermal power station according to  claim 6 , wherein an output line for discharging waste combustion gases from the combustion chamber is provided, where the output line comprises a line portion leading into the air preheater and an additional line portion leading into a water preheater of the water-steam cycle. 
     
     
         10 . The thermal power station according to  claim 1 , wherein an electrical heating element, including a resistance heater, is installed in the heat exchanger. 
     
     
         11 . A method for storing heat in a thermal power station which comprises a steam generator with a combustion chamber and a feed for combustion air and a water-steam cycle, said method having the following steps:
 conveying a heat store medium when it is cold from a first container via a heat exchanger to a second container,   conducting water and steam from the water-steam cycle ( 5 ) through the heat exchanger with heat being exchanged with the heat store medium,   conveying the heat store medium when it is hot from the second container via an additional heat exchanger into the first container,   conducting air through the additional heat exchanger with heat being exchanged with the heat store medium when it is hot, and   feeding the air as combustion air into the combustion chamber.