Ice machine for an ice-based thermal storage system

Abstract

An ice machine for an ice-based thermal storage system comprises a plurality of pillow plates arranged in a plate bank, wherein each of the plurality of pillow plates includes an inlet connection and an outlet connection, with the respective inlet connections connected to a feed header, and with the respective outlet connections connected to a suction header. A water distribution pan is positioned at a top of the plate bank, and a tank is positioned below the plate bank. As an evaporator, the ice machine causes ice to form on the pillow plates, which then falls into the tank. As a condenser, the ice machine transfers heat to water flowing over the pillow plates, such that water at an increased temperature falls into the tank and melts the ice in the tank.

What is claimed is: 
     
         1 . An ice machine for an ice-based thermal storage system, comprising:
 a plurality of pillow plates arranged in a plate bank, wherein each of the plurality of pillow plates includes an inlet connection and an outlet connection, with the respective inlet connections connected to a feed header, and with the respective outlet connections connected to a suction header;   a water distribution pan positioned at a top of the plate bank; and   a tank positioned below the plate bank;   wherein the ice machine is configured for use both as an evaporator and as a condenser.   
     
     
         2 . The ice machine as recited in  claim 1 , wherein, in use as the evaporator, a refrigerant is received by the feed header via a first line connecting a refrigeration system to the feed header, is introduced into the plurality of pillow plates, and then exits via the suction header, such that heat from water distributed from the water distribution pan over the plurality of pillow plates is transferred to the refrigerant, thus forming ice on the plurality of pillow plates, which then falls into the tank positioned below the plate bank. 
     
     
         3 . The ice machine as recited in  claim 2 , wherein, in use as the condenser, a hot gaseous refrigerant is received by the feed header via a second line connecting the refrigeration system to the feed header, is introduced into the plurality of pillow plates, and then exits via the suction header, such that heat from the hot gaseous refrigerant is transferred to water distributed from the water distribution pan over the plurality of pillow plates, such that water at an increased temperature falls into the tank positioned below the plate bank. 
     
     
         4 . The ice machine as recited in  claim 3 , and further comprising:
 a first valve installed in the first line, which is open when the ice machine is in use as the evaporator, thus allowing the refrigerant to flow into the feed header, and is closed when the ice machine is in use as the condenser; and   a second valve installed in the second line, which is open when the ice machine is in use as the condenser, thus allowing the hot gaseous refrigerant to flow into the feed header, and is closed when the ice machine is in use as the condenser.   
     
     
         5 . The ice machine as recited in  claim 4 , and further comprising a control system that is operably connected to and communicates control signals to the first valve and the second valve. 
     
     
         6 . The ice machine as recited in  claim 1 , and further comprising a pump configured to recirculate water from the tank to the water distribution pan. 
     
     
         7 . The ice machine as recited in  claim 1 , each of the plurality of pillow plates is comprised of two side walls that are joined together and define an internal cavity. 
     
     
         8 . The ice machine as recited in  claim 2 , wherein the refrigerant is received from the refrigeration system of a power generation plant. 
     
     
         9 . The ice machine as recited in  claim 3 , wherein the hot gaseous refrigerant is received from the refrigeration system of a power generation plant. 
     
     
         10 . The ice machine as recited in  claim 1 , wherein the inlet connection of each of the plurality of pillow plates includes a branch connection configured to feed warm gas into the pillow plate at predetermined time intervals. 
     
     
         11 . An ice machine for an ice-based thermal storage system, comprising:
 a plurality of pillow plates arranged in a plate bank, wherein each of the plurality of pillow plates is comprised of two side walls that are joined together and define an internal cavity, and wherein each of the plurality of pillow plates includes an inlet connection and an outlet connection, with the respective inlet connections connected to a feed header, and with the respective outlet connections connected to a suction header;   a water distribution pan positioned at a top of the plate bank and configured to distribute water over the respective side walls of each of the plurality of pillow plates; and   a tank positioned below the plate bank;   wherein, in use as an evaporator, a refrigerant is received by the feed header, is introduced into the respective internal cavities defined by the plurality of pillow plates, and then exits via the suction header, such that heat from water distributed from the water distribution pan over the respective side walls of each of the plurality of pillow plates is transferred to the refrigerant, thus forming ice on respective side walls of each of the plurality of pillow plates, which then falls into the tank positioned below the plate bank; and   wherein, in use as a condenser, a hot gaseous refrigerant is received by the feed header, is introduced into the respective internal cavities defined by the plurality of pillow plates, and then exits via the suction header, such that heat from the hot gaseous refrigerant is transferred to water distributed from the water distribution pan over the respective side walls of each of the plurality of pillow plates, such that water at an increased temperature falls into the tank positioned below the plate bank.   
     
     
         12 . The ice machine as recited in  claim 1 , and further comprising:
 a first line delivering the refrigerant to the feed header;   a first valve installed in the first line, which is open when the ice machine is in use as the evaporator, thus allowing the refrigerant to flow into the feed header, and is closed when the ice machine is in use as the condenser;   a second line delivering the hot gaseous refrigerant to the feed header; and   a second valve installed in the second line, which is open when the ice machine is in use as the condenser, thus allowing the hot gaseous refrigerant to flow into the feed header, and is closed when the ice machine is in use as the condenser.   
     
     
         13 . The ice machine as recited in  claim 12 , and further comprising a control system that is operably connected to and communicates control signals to the first valve and the second valve. 
     
     
         14 . The ice machine as recited in  claim 11 , and further comprising a pump configured to recirculate water from the tank to the water distribution pan. 
     
     
         15 . A thermal storage system, comprising:
 an ice machine, including
 a plurality of pillow plates arranged in a plate bank, wherein each of the plurality of pillow plates is comprised of two side walls that are joined together and define an internal cavity, and wherein each of the plurality of pillow plates includes an inlet connection and an outlet connection, with the respective inlet connections connected to a feed header, and with the respective outlet connections connected to a suction header, 
 a water distribution pan positioned at a top of the plate bank and configured to distribute water over the respective side walls of each of the plurality of pillow plates, and 
 a tank positioned below the plate bank; 
   a refrigeration system, which is in fluid communication with the feed header of the ice machine, and in is fluid communication with the suction header of the ice machine;   wherein, in a first configuration, a refrigerant is supplied by the refrigeration system to the feed header, is introduced into the respective internal cavities defined by the plurality of pillow plates, and then exits via the suction header, such that heat from water distributed from the water distribution pan over the respective side walls of each of the plurality of pillow plates is transferred to the refrigerant, thus forming ice on respective side walls of each of the plurality of pillow plates, which then falls into the tank positioned below the plate bank; and   wherein, in a second configuration, a hot gaseous refrigerant is supplied by the refrigeration system to the feed header, is introduced into the respective internal cavities defined by the plurality of pillow plates, and then exits via the suction header, such that heat from the hot gaseous refrigerant is transferred to water distributed from the water distribution pan over the respective side walls of each of the plurality of pillow plates, such that water at an increased temperature falls into the tank positioned below the plate bank.   
     
     
         16 . The thermal storage system as recited in  claim 15 , and further comprising:
 a first line connecting the refrigeration system to the feed header, delivering the refrigerant to the feed header;   a first valve installed in the first line and positioned between the refrigeration system and the feed header, which is open in the first configuration, thus allowing the refrigerant from the refrigeration system to flow to the feed header, and is closed in the second configuration;   a second line connecting the refrigeration system to the feed header, delivering the hot gaseous refrigerant to the feed header; and   a second valve installed in the second line and positioned between the refrigeration system and the feed header, which is open in the second configuration, thus allowing the hot gaseous refrigerant from the refrigeration system to flow to the feed header, and is closed in the first configuration.   
     
     
         17 . The thermal storage system as recited in  claim 16 , and further comprising:
 a third line connecting the suction header to the refrigeration system, returning the refrigerant to the refrigeration system as a two-phase or gaseous fluid;   a third valve installed in the third line and positioned between the suction header and the refrigeration system, which is open in the first configuration, thus allowing the refrigerant to return to the refrigeration system, and is closed in the second configuration;   a fourth line connecting the suction header to the refrigeration system, returning the hot gaseous refrigerant to the refrigeration system; and   a fourth valve installed in the fourth line and positioned between the suction header and the refrigeration system, which is open in the second configuration, thus allowing the hot gaseous refrigerant from the refrigeration system to return to the refrigeration system, and is closed in the first configuration.   
     
     
         18 . The thermal storage system as recited in  claim 16 , and further comprising a control system that is operably connected to and communicates control signals to the first valve and the second valve. 
     
     
         19 . The thermal storage system as recited in  claim 17 , and further comprising a control system that is operably connected to and communicates control signals to each of the first valve, the second valve, the third valve, and the fourth valve. 
     
     
         20 . The thermal storage system as recited in  claim 15 , and further comprising a pump configured to recirculate water from the tank to the water distribution pan. 
     
     
         21 . The thermal storage system as recited in  claim 15 , wherein the refrigeration system is associated with a power generation plant.