Frost-resistant steam circuit process device and its method of operation

Abstract

The invention concerns a steam circuit process device comprising a reservoir for a liquid working medium; a feed pump for supplying working medium from the reservoir to an evaporator, in which the working medium is evaporated; an expander, to which vaporised working medium is fed by the evaporator, which expands by way of performing mechanical work in the expander; a condenser, which follows the expander and is in fluid connection with the reservoir, whereas the working medium is liquefied in the condenser; The invention is characterised in that the steam circuit process device includes an emptying pump for the working medium which is arranged in a by-pass line between the reservoir and a switchable valve system in fluid communication with at least one further component of the steam circuit process device.

1 . A steam circuit process device comprising
   1 . 1  a reservoir ( 1 ) for a liquid working medium;     1 . 2  a feed pump ( 2 ) for supplying working medium from the reservoir ( 1 ) to an evaporator ( 3 ), in which the working medium is evaporated;     1 . 3  an expander ( 4 ), to which vaporised working medium is fed by the evaporator ( 3 ), which expands by way of performing mechanical work in the expander ( 4 );     1 . 4  a condenser ( 5 ), which follows the expander ( 4 ) and is in fluid connection with the reservoir ( 1 ), whereas the working medium is liquefied in the condenser ( 5 ); characterised in that     1 . 5  the steam circuit process device includes an emptying pump ( 6 ) for the working medium, which is arranged in a by-pass line ( 7 ) between the reservoir ( 1 ) and a switchable valve system ( 8 ) in fluid communication with at least one further component of the steam circuit process device.   
     
     
         2 . The steam circuit process device according to  claim 1 , characterised in that the emptying pump ( 6 ) is designed as a reversible pump conveying in two flow directions. 
     
     
         3 . The steam circuit process device according to  claim 1 , characterised in that the emptying pump ( 6 ) has a dry-run capability. 
     
     
         4 . The steam circuit process device according to  claim 1 , characterised in that the emptying pump ( 6 ) is frost-resistant. 
     
     
         5 . The steam circuit process device according to  claim 1 , characterised in that a control device ( 9 ) is associated with the emptying pump ( 6 ) and the valve system ( 8 ), which is connected at least indirectly to a temperature sensor ( 10 ) to determine the surrounding temperature and/or the operating temperature of the steam circuit process device. 
     
     
         6 . The steam circuit process device according to  claim 5 , characterised in that the control device ( 9 ) is directly connected to another power supply to ensure power supply with a battery ( 11 ). 
     
     
         7 . The steam circuit process device according to  claim 1 , characterised in that the emptying pump ( 6 ) has no dry-run capability and the valve system ( 8 ) is connected at least indirectly to the feed pump ( 2 ) so that the emptying pump ( 6 ) floods the feed pump ( 2 ) with working medium during scooping operation from the reservoir ( 1 ). 
     
     
         8 . A method for operating a steam circuit process device comprising
   8 . 1  a reservoir ( 1 ) for a liquid working medium;     8 . 2  a feed pump ( 2 ) for supplying working medium from the reservoir ( 1 ) to an evaporator ( 3 ), in which the working medium is evaporated;     8 . 3  an expander ( 4 ), to which vaporised working medium is fed by the evaporator ( 3 ), which expands by way of performing mechanical work in the expander ( 4 );     8 . 4  a condenser ( 5 ), which follows the expander ( 4 ) and is in fluid connection with the reservoir ( 1 ), whereas the working medium is liquefied in the condenser ( 5 ); characterised in that     8 . 5  the working medium is returned to the reservoir ( 1 ) after shutdown of the steam circuit process device, by means of an emptying pump ( 6 ) for the working medium which is arranged in a by-pass line ( 7 ) between the reservoir ( 1 ) and a switchable valve system ( 8 ) in fluid communication with at least one further component of the steam circuit process device.   
     
     
         9 . The method for operating a steam circuit process device according to  claim 8 , characterised in that the feed pump ( 2 ) is flooded with working medium by the emptying pump ( 6 ) during scooping operation when starting the steam circuit process device. 
     
     
         10 . The steam circuit process device according to  claim 2 , characterised in that the emptying pump ( 6 ) has a dry-run capability. 
     
     
         11 . The steam circuit process device according to  claim 2 , characterised in that the emptying pump ( 6 ) is frost-resistant. 
     
     
         12 . The steam circuit process device according to  claim 3 , characterised in that the emptying pump ( 6 ) is frost-resistant. 
     
     
         13 . The steam circuit process device according to  claim 2 , characterised in that a control device ( 9 ) is associated with the emptying pump ( 6 ) and the valve system ( 8 ), which is connected at least indirectly to a temperature sensor ( 10 ) to determine the surrounding temperature and/or the operating temperature of the steam circuit process device. 
     
     
         14 . The steam circuit process device according to  claim 3 , characterised in that a control device ( 9 ) is associated with the emptying pump ( 6 ) and the valve system ( 8 ), which is connected at least indirectly to a temperature sensor ( 10 ) to determine the surrounding temperature and/or the operating temperature of the steam circuit process device. 
     
     
         15 . The steam circuit process device according to  claim 4 , characterised in that a control device ( 9 ) is associated with the emptying pump ( 6 ) and the valve system ( 8 ), which is connected at least indirectly to a temperature sensor ( 10 ) to determine the surrounding temperature and/or the operating temperature of the steam circuit process device. 
     
     
         16 . The steam circuit process device according to  claim 2 , characterised in that the emptying pump ( 6 ) has no dry-run capability and the valve system ( 8 ) is connected at least indirectly to the feed pump ( 2 ) so that the emptying pump ( 6 ) floods the feed pump ( 2 ) with working medium during scooping operation from the reservoir ( 1 ). 
     
     
         17 . The steam circuit process device according to  claim 3 , characterised in that the emptying pump ( 6 ) has no dry-run capability and the valve system ( 8 ) is connected at least indirectly to the feed pump ( 2 ) so that the emptying pump ( 6 ) floods the feed pump ( 2 ) with working medium during scooping operation from the reservoir ( 1 ). 
     
     
         18 . The steam circuit process device according to  claim 4 , characterised in that the emptying pump ( 6 ) has no dry-run capability and the valve system ( 8 ) is connected at least indirectly to the feed pump ( 2 ) so that the emptying pump ( 6 ) floods the feed pump ( 2 ) with working medium during scooping operation from the reservoir ( 1 ). 
     
     
         19 . The steam circuit process device according to  claim 5 , characterised in that the emptying pump ( 6 ) has no dry-run capability and the valve system ( 8 ) is connected at least indirectly to the feed pump ( 2 ) so that the emptying pump ( 6 ) floods the feed pump ( 2 ) with working medium during scooping operation from the reservoir ( 1 ). 
     
     
         20 . The steam circuit process device according to  claim 6 , characterised in that the emptying pump ( 6 ) has no dry-run capability and the valve system ( 8 ) is connected at least indirectly to the feed pump ( 2 ) so that the emptying pump ( 6 ) floods the feed pump ( 2 ) with working medium during scooping operation from the reservoir ( 1 ).