Utilization of Exhaust of Low Pressure Condensing Steam Turbine as Heat Input to Silica Gel-Water Working Pair Adsorption Chiller

Abstract

A device and method for utilizing waste heat from the exhaust of a low pressure condensing steam turbine. An adsorption chiller is driven by heat recovered from the exhaust steam by incorporating a heat exchanger between the low pressure condensing steam turbine and the condenser of the steam turbine. The heat exchanger provides heated fluid which is then utilized as the hot water for the adsorption chiller. The adsorption chiller outputs chilled water which may be beneficially used for many purposes in the power plant.

1 . A low pressure condensing steam turbine of the type directing exhaust steam to a steam turbine condenser comprising a heat exchanger intermediate to the low pressure condensing steam turbine and the steam turbine condenser, said heat exchanger providing a flow of heated fluid to drive an adsorption chiller system. 
     
     
         2 . The low pressure condensing steam turbine of  claim 1  wherein the heated fluid produced by said heat exchanger comprises water having a temperature of about 85° C. to about 90° C. 
     
     
         3 . The low pressure condensing steam turbine of  claim 1  wherein the exhaust steam utilized comprises a mixture of water and water vapor having a temperature in the range of about 111° C. to about 125° C. 
     
     
         4 . The low pressure condensing steam turbine of  claim 1  wherein the adsorption chiller system comprises a silica gel-water working pair adsorption chiller operatively connected to said heat exchanger. 
     
     
         5 . The low pressure condensing steam turbine of  claim 1  wherein said low pressure condensing steam turbine comprises a steam turbine of a power plant having a heat sink for the dissipation of waste heat, and wherein the condenser transfers the heat captured from the condensing steam to the heat sink of the plant as waste heat, and wherein the adsorption chiller system also transfers the heat gained from its operation to the heat sink of the plant as waste heat, thereby increasing the total heat load on the heat sink of the plant without having increased the heat load input into the plant. 
     
     
         6 . The low pressure condensing steam turbine of  claim 1  wherein the adsorption chiller outputs chilled water. 
     
     
         7 . The low pressure condensing steam turbine of  claim 6  wherein the chilled water is used to reduce the temperature of the inlet air entering a gas turbine of a combined cycle power plant. 
     
     
         8 . The low pressure condensing steam turbine of  claim 6  wherein the chilled water is used to provide intercooling of the air as it passes through one or more compressor stages of a gas turbine of a combined cycle power plant. 
     
     
         9 . A method of extracting additional work from the waste heat of a steam turbine of a power plant comprising:
 (a) incorporating a heat exchanger for outputting a flow of heated fluid between an exhaust outlet of a low pressure steam turbine of said power plant and a condenser of said steam turbine;   (b) directing the heated fluid to an adsorption chiller; and   (c) outputting chilled water from the adsorption chiller.   
     
     
         10 . The method of  claim 9  wherein the power plant further comprises a combined cycle plant having a gas turbine, and wherein the efficiency of the plant is increased by using the chilled water to reduce the temperature of the inlet air entering the gas turbine. 
     
     
         11 . The method of  claim 9  wherein the power plant further comprises a combined cycle plant having a gas turbine having one or more compressor stages, and wherein the efficiency of the plant is increased by using the chilled water to provide intercooling of the air as it passes through one or more the compressor stages of the gas turbine. 
     
     
         12 . The method of  claim 9  wherein the incorporating step comprises adding one or more water-cooled surface condensers to between the exhaust outlet and the condenser of an existing steam turbine. 
     
     
         13 . The method of  claim 9  wherein the incorporating step comprises redirecting one or more portions of the existing condenser to output the flow of heated fluid to the adsorption chiller. 
     
     
         14 . The method of  claim 9  wherein the directing step further comprises connecting the flow of heated fluid from the heat exchanger to the adsorption heat exchanger circuit, a portion of which is contained within an adsorbent heat exchanger chamber of the adsorption chiller. 
     
     
         15 . The method of  claim 9  wherein the heated fluid produced by said heat exchanger comprises water having a temperature of about 85° to about 90° C. 
     
     
         16 . The method of  claim 9  wherein the waste heat of the steam turbine comprises exhaust steam from a low pressure condensing steam turbine, said exhaust steam comprising a mixture of water and water vapor having a temperature in the range of about 111° C. to about 125° C. 
     
     
         17 . The method of  claim 9  wherein the adsorption chiller comprises a silica gel-water working pair adsorption chiller.