Steam seal header, method of using a steam seal header and steam turbine system incorporating a steam seal header

Abstract

A steam turbine system for use in a power plant includes a steam seal header that collects steam from seals of a high pressure steam turbine and an intermediate pressure steam turbine. The collected steam is provided to seals of a low pressure steam turbine to ensure the seals provide an effective seal for the low pressure steam turbine. Steam from the low pressure steam turbine is also collected in the steam seal header and it is mixed with the steam collected from the high and intermediate pressure seals. The mixed steam is then provided to drive the low pressure steam turbine.

What is claimed is: 
     
         1 . A method of utilizing steam provided by a seal of a high pressure steam turbine or a seal of an intermediate pressure steam turbine, comprising:
 receiving a first flow of steam from at least one of a seal of a high pressure steam turbine and a seal of an intermediate pressure stream turbine in a steam seal header;   receiving a second flow of steam from a first location in a low pressure steam turbine in the steam seal header; and   providing a third flow of steam from the steam seal header to a second location in the low pressure steam turbine, wherein the third flow of steam comprises a mixture of the first and second flows of steam.   
     
     
         2 . The method of  claim 1 , wherein the first flow of steam comprises steam from a seal of an intermediate steam turbine and steam from a seal of a high pressure steam turbine. 
     
     
         3 . The method of  claim 1 , wherein the first flow of steam and the second flow of steam mix together in the steam seal header to form the third flow of steam. 
     
     
         4 . The method of  claim 1 , further comprising providing a fourth flow of steam from the steam seal header to a seal of the low pressure steam turbine. 
     
     
         5 . The method of  claim 4 , wherein the fourth flow of steam is at substantially the same temperature and pressure as the third flow of steam. 
     
     
         6 . The method of  claim 4 , wherein the fourth flow of steam is at a different temperature and pressure than the third flow of steam. 
     
     
         7 . A steam seal header, comprising:
 a main body configured to hold a volume of steam;   a first inlet into the main body that is configured to receive a first flow of steam from at least one of a seal of an intermediate pressure steam turbine and a seal of a high pressure steam turbine;   a second inlet into the main body that is configured to receive a second flow of steam from a first location in a low pressure steam turbine;   a first outlet from the main body that is configured to output a third flow of steam from the main body to a second location in the low pressure steam turbine; and   a second outlet from the main body that is configured to output a fourth flow of steam to a seal of the low pressure steam turbine.   
     
     
         8 . The steam seal header of  claim 7 , wherein the main body is configured to mix at least portions of the first and second flows of steam to create the third flow of steam. 
     
     
         9 . The steam seal header of  claim 7 , further comprising a partition member located in the main body, wherein the partition member separates the main body into a first chamber that holds only the first flow of steam and a second chamber that holds a mixture of the first and second flows of steam. 
     
     
         10 . The steam seal header of  claim 9 , wherein the first inlet and the second outlet open into the first chamber and wherein the second inlet and the first outlet open into the second chamber of the main body. 
     
     
         11 . The steam seal header of  claim 10 , further comprising an aperture in the partition that allows at least a portion of the first flow of steam received through the first inlet to pass from the first chamber into the second chamber. 
     
     
         12 . The steam seal header of  claim 11 , further comprising a valve that is operatively coupled to the aperture in the partition, wherein the valve controls an amount of the first flow of steam that passes from the first chamber into the second chamber. 
     
     
         13 . The steam seal turbine of  claim 12 , wherein the valve is an expansion valve. 
     
     
         14 . A steam turbine system for use in a power plant, comprising:
 a high pressure steam turbine;   at least one high pressure seal for the high pressure steam turbine;   a low pressure steam turbine;   a steam seal header that receives a first flow of steam from the high pressure seal and a second flow of steam from the low pressure steam turbine, and that outputs a third flow of steam to the low pressure steam turbine, wherein the third flow of steam comprises a mixture of the first and second flows of steam.   
     
     
         15 . The steam turbine system of  claim 14 , further comprising a low pressure seal for the low pressure steam turbine, wherein the steam seal header outputs a fourth flow of steam to the low pressure seal. 
     
     
         16 . The steam turbine system of  claim 15 , wherein the steam seal header is configured such that the third and fourth flows of steam output by the steam seal header are at substantially the same temperature and pressure. 
     
     
         17 . The steam turbine system of  claim 15 , wherein the steam seal header is configured such that the third flow of steam is at a different temperature and pressure than the fourth flow of steam. 
     
     
         18 . The steam turbine system of  claim 17 , wherein the fourth flow of steam is at substantially the same temperature and pressure as the first flow of steam. 
     
     
         19 . The steam turbine system of  claim 18 , wherein the steam seal header is configured such that the third flow of steam comprises a mixture of at least a portion of first flow of steam and at least a portion of the second flow of steam. 
     
     
         20 . The steam turbine system of  claim 14 , further comprising:
 an intermediate pressure steam turbine; and   an intermediate seal for the intermediate pressure steam turbine, wherein the first flow of steam received by the steam seal header comprises a mixture of steam from the high pressure seal and steam from the intermediate pressure seal.