High efficiency power production methods, assemblies, and systems

Abstract

The present disclosure provides methods, assemblies, and systems for power production that can allow for increased efficiency and lower cost components arising from the control, reduction, or elimination of turbine blade mechanical erosion by particulates or chemical erosion by gases in a combustion product flow. The methods, assemblies, and systems can include the use of turbine blades that operate with a blade velocity that is significantly reduced in relation to conventional turbines used in typical power production systems. The methods and systems also can make use of a recycled circulating fluid for transpiration protection of the turbine and/or other components. Further, recycled circulating fluid may be employed to provide cleaning materials to the turbine.

1 . A method of power generation comprising:
 introducing a fuel, O 2 , and a circulating fluid into a combustor;   combusting the fuel in the combustor to provide a combustion product stream including the circulating fluid and a content of particulates, the combustion product stream flowing at a defined velocity; and   expanding the combustion product stream across a turbine comprising a plurality of turbine blades to generate power and output a turbine discharge stream, the turbine being operated such that the turbine blades rotate at a blade velocity of less than about 500 mph.   
     
     
         2 . The method of  claim 1 , further comprising passing the turbine discharge stream through a filter configured to remove substantially all of the particulates contained in the turbine discharge stream and form a filtered turbine discharge stream. 
     
     
         3 . The method of  claim 2 , further comprising passing the filtered turbine discharge stream through a heat exchanger to provide a cooled turbine discharge stream;
 treating the cooled turbine discharge stream to withdraw one or more components of the turbine discharge stream; and   passing the treated turbine discharge stream back through the heat exchanger to provide a heated, recycled circulating fluid stream.   
     
     
         4 . The method of  claim 3 , further comprising directing at least a portion of the heated, recycled circulating fluid stream to the combustor. 
     
     
         5 . The method of  claim 3 , further comprising directing at least a portion of the heated, recycled circulating fluid stream to the turbine. 
     
     
         6 . The method of  claim 3 , further comprising directing at least a portion of the heated, recycled circulating fluid stream to a cleaning material unit wherein the heated, recycled circulating fluid stream is combined with a cleaning material to form a cleaning material stream, the cleaning material in the cleaning material stream being configured to remove deposits on the turbine blades arising from the content of particulates present in the combustion product stream. 
     
     
         7 . The method of  claim 6 , wherein the cleaning material stream is input directly into the turbine. 
     
     
         8 . The method of  claim 6 , wherein the cleaning material stream is combined with the combustion product stream to form a combined combustion product and cleaning material stream that is directed into the turbine. 
     
     
         9 . The method of  claim 1 , wherein the circulating fluid comprises CO 2 . 
     
     
         10 . The method of  claim 9 , wherein the CO 2  is provided in a supercritical state. 
     
     
         11 . The method of  claim 1 , further comprising combining the filtered turbine discharge stream with a particulate sold fuel to form an additional fuel in the form of a slurry; and
 introducing the additional fuel to the combustor.   
     
     
         12 . The method of  claim 3 , further comprising using at least a portion of the circulating fluid that is recycled as a transpiration fluid. 
     
     
         13 . The method of  claim 12 , wherein using the circulating fluid that is recycled as the transpiration fluid comprises transpiring the transpiration fluid to an exterior surface of the turbine blades. 
     
     
         14 . The method of  claim 13 , wherein transpiring the transpiration fluid to the exterior surface of the turbine blades comprises transpiring the transpiration fluid through a porous sintered material. 
     
     
         15 . A power generation system comprising:
 a combustor configured for receiving a fuel, O 2 , and a circulating fluid, and having at least one combustion stage that combusts the fuel and provides a combustion product stream including the circulating fluid and a content of particulates;   a turbine in fluid communication with the combustor, the turbine having an inlet for receiving the combustion product stream, an outlet for release of a turbine discharge stream, and a plurality of turbine blades of sufficient dimensions such that the turbine operates at a blade velocity of less than about 500 mph; and   a filter in fluid communication with the outlet of the turbine and configured to produce a filtered turbine discharge stream.   
     
     
         16 . The power generation system of  claim 15 , further comprising a heat exchanger in fluid communication with the filter and configured to receive the filtered turbine discharge stream. 
     
     
         17 . The power generation system of  claim 16 , further comprising a cleaning material unit in fluid communication with the heat exchanger, the cleaning material unit being configured to combine a cleaning material with a fluid stream received from the heat exchanger to form a cleaning material stream. 
     
     
         18 . The power generation system of  claim 17 , further comprising a flow combiner switch configured to combine the cleaning material stream with the combustion product stream to form a combined combustion product and cleaning material stream and direct the combined combustion product and cleaning material stream to the turbine. 
     
     
         19 . The power generation system of  claim 15 , wherein the blades comprise a porous sintered material, the porous sintered material configured to direct a transpiration fluid to an exterior surface of the blades. 
     
     
         20 . The power generation system of  claim 19 , wherein the porous sintered material defines the entirety of the exterior surface of the blades. 
     
     
         21 . The power generation system of  claim 19 , wherein the turbine comprises a rotor, and
 wherein the rotor comprises the porous sintered material and the porous sintered material is configured to direct the transpiration fluid to an exterior surface of the rotor.   
     
     
         22 . A method of power generation comprising:
 introducing a fuel, O 2 , and a CO 2  circulating fluid into a combustor;   combusting the fuel to provide a combustion product stream comprising CO 2 ;   expanding the combustion product stream across a turbine to generate power and output a turbine discharge stream;   processing the turbine discharge stream to recycle at least a portion of the CO 2  circulating fluid into the combustor;   withdrawing a portion of the CO 2  circulating fluid that is recycled; and   using the recycled CO 2  circulating fluid as a transpiration fluid.   
     
     
         23 . The method of  claim 22 , wherein using the recycled CO 2  circulating fluid as the transpiration fluid comprises transpiring the recycled CO 2  circulating fluid in the turbine. 
     
     
         24 . The method of  claim 22 , wherein using the recycled CO 2  circulating fluid as the transpiration fluid comprises transpiring the recycled CO 2  circulating in the combustor. 
     
     
         25 . The method of  claim 22 , further comprising directing the combustion product stream from the combustor through a conduit to the turbine,
 wherein using the recycled CO 2  circulating fluid as the transpiration fluid comprises transpiring the recycled CO 2  circulating fluid in the conduit.   
     
     
         26 . The method of  claim 22 , further comprising conditioning the recycled CO 2  circulating fluid to a temperature that is less than a temperature of the combustion product stream. 
     
     
         27 . The method of  claim 22 , further comprising conditioning the recycled CO 2  circulating fluid to a temperature that is substantially equal to a temperature of the combustion product stream. 
     
     
         28 . The method of  claim 22 , further comprising conditioning the recycled CO 2  circulating fluid to a temperature that is greater than a temperature of the combustion product stream. 
     
     
         29 . A power generation system comprising:
 a combustor configured for receiving a fuel, O 2 , and a CO 2  circulating fluid stream, and having at least one combustion stage that combusts the fuel in the presence of the CO 2  circulating fluid stream and provides a combustion product stream comprising CO 2 ;   a turbine in fluid communication with the combustor, the turbine having an inlet for receiving the combustion product stream, an outlet for release of a turbine discharge stream comprising CO 2 , and a plurality of turbine blades;   one or more components configured for processing the turbine discharge stream to form a recycled CO 2  circulating fluid stream,   wherein one or more components of the system are configured for using a portion of the recycled CO 2  circulating fluid stream as a transpiration fluid.   
     
     
         30 . The power generation system of  claim 29 , wherein the one or more components configured for processing the turbine discharge stream to form the recycled CO 2  circulating fluid stream comprise a filter. 
     
     
         31 . The power generation system of  claim 30 , wherein the one or more components configured for processing the turbine discharge stream to form the recycled CO 2  circulating fluid stream further comprise a heat exchanger. 
     
     
         32 . The power generation system of  claim 31 , wherein the one or more components configured for processing the turbine discharge stream to form the recycled CO 2  circulating fluid stream further comprise a separator. 
     
     
         33 . The power generation system of  claim 32 , wherein the one or more components configured for processing the turbine discharge stream to form the recycled CO 2  circulating fluid stream further comprise a compressor. 
     
     
         34 . The power generation system of  claim 29 , wherein the one or more components configured for using the portion of the recycled CO 2  circulating fluid stream as the transpiration fluid comprise a porous sintered material configured for receiving the transpiration fluid therethrough. 
     
     
         35 . The power generation system of  claim 29 , wherein the turbine blades have a blade height less than about 0.275 m. 
     
     
         36 . The power generation system of  claim 29 , wherein the turbine comprises less than about 2000 of the turbine blades. 
     
     
         37 . The power generation system of  claim 29 , wherein a ratio of a length of the turbine to an average diameter of the blades is greater than about 4. 
     
     
         38 . A turbine assembly, comprising:
 a plurality of components including:
 a casing defining:
 an inlet configured to receive a combustion product stream, and 
 an outlet; 
 
 a rotor positioned in the casing; and 
 a plurality of blades extending from the rotor, 
   wherein one or more of the components comprise a porous sintered material, the porous sintered material configured to direct a transpiration fluid therethrough.   
     
     
         39 . The turbine assembly of  claim 38 , wherein the porous sintered material defines the entirety of the exterior surface of the blades. 
     
     
         40 . The turbine assembly of  claim 38 , wherein the casing comprises the porous sintered material and the porous sintered material is configured to direct the transpiration fluid to an interior surface of the casing. 
     
     
         41 . The turbine assembly of  claim 38 , wherein the rotor comprises the porous sintered material and the porous sintered material is configured to direct the transpiration fluid to an exterior surface of the rotor. 
     
     
         42 . The turbine assembly of  claim 38 , wherein the rotor comprises an annular flow diverter configured to divert the combustion product stream around the rotor. 
     
     
         43 . The turbine assembly of  claim 38 , further comprising an inlet conduit coupled to the inlet of the casing and configured to couple to an outlet of a combustor assembly and receive the combustion product stream therefrom,
 wherein the inlet conduit comprises the porous sintered material and the porous sintered material is configured to direct the transpiration fluid to an interior surface of the inlet conduit.   
     
     
         44 . The turbine assembly of  claim 38 , wherein the inlet of the casing is configured to couple directly to an outlet of a combustor assembly. 
     
     
         45 . The turbine assembly of  claim 44 , wherein the inlet of the casing is configured to receive the combustion product stream from a plurality of combustors radially disposed with respect to a major axis defined by the rotor. 
     
     
         46 . The turbine assembly of  claim 38 , wherein the blades comprise the porous sintered material, the porous sintered material configured to direct the transpiration fluid to an exterior surface of the blades. 
     
     
         47 . The turbine assembly of  claim 46 , wherein the blades respectively further comprise at least one reinforcement member. 
     
     
         48 . The turbine assembly of  claim 47 , wherein the reinforcement member comprises a rod that extends through the porous sintered material in each of the blades. 
     
     
         49 . The turbine assembly of  claim 48 , wherein the reinforcement member comprises a core,
 wherein the porous sintered material extends around the core.   
     
     
         50 . The turbine assembly of  claim 49 , wherein the core defines one or more channels configured to receive the transpiration fluid and direct the transpiration fluid into the porous sintered material. 
     
     
         51 . The turbine assembly of  claim 46 , wherein one or more channels are defined in the blades, and
 wherein the channels are configured to receive the transpiration fluid and direct the transpiration fluid into the porous sintered material.   
     
     
         52 . The turbine assembly of  claim 46 , wherein each of the blades extends from a leading edge to a trailing edge, and
 wherein the blades are configured to define a flow of the transpiration fluid at the leading edge that is greater than a flow of the transpiration fluid at the trailing edge.   
     
     
         53 . The turbine assembly of  claim 52 , wherein each of the blades defines a transpiration fluid inlet area at the leading edge that is greater than a transpiration fluid inlet area at the trailing edge. 
     
     
         54 . The turbine assembly of  claim 52  wherein each of the blades defines a wall thickness that is greater at the trailing edge than at the leading edge. 
     
     
         55 . The turbine assembly of  claim 46 , wherein each of the blades extends from a root at the rotor to a tip, and
 wherein the porous sintered material defines a porosity that varies between the root and the tip.   
     
     
         56 . The turbine assembly of  claim 55 , wherein the porosity of the porous sintered material is configured to define a flow of the transpiration fluid at the tip that is greater than a flow of the transpiration fluid at the root. 
     
     
         57 . The turbine assembly of  claim 55 , wherein the porosity of the porous sintered material is configured to define a flow of the transpiration fluid at the tip that is substantially equal to a flow of the transpiration fluid at the root. 
     
     
         58 . The turbine assembly of  claim 55 , wherein the porous sintered material defines a plurality of layers, wherein the porosity of the layers increases from the root to the tip. 
     
     
         59 . The turbine assembly of  claim 46 , wherein the blades each respectively define an integral structure comprising a plurality of internal ribs. 
     
     
         60 . The turbine assembly of  claim 38 , wherein the components further comprise a plurality of stators, wherein the stators comprise the porous sintered material and the porous sintered material is configured to direct the transpiration fluid to an exterior surface of the stators. 
     
     
         61 . The turbine assembly of  claim 38 , further comprising one or more seals, wherein one or more of the components are configured to direct the transpiration fluid to the seals. 
     
     
         62 . The turbine assembly of  claim 61 , wherein the seals comprise the porous sintered material. 
     
     
         63 . A turbine assembly, comprising:
 a casing defining:
 an inlet configured to receive a combustion product stream, and 
 an outlet; 
   a rotor positioned in the casing; and   a plurality of blades extending from the rotor,   wherein a ratio of a length of the turbine assembly to an average diameter of the blades is greater than about 4.   
     
     
         64 . The turbine assembly of  claim 63 , wherein the turbine blades have a blade height less than about 0.275 m. 
     
     
         65 . The turbine assembly of  claim 63 , wherein the turbine assembly comprises less than about 2,000 of the blades. 
     
     
         66 . The turbine assembly of  claim 63 , wherein the blades are transpiration protected. 
     
     
         67 . The turbine assembly of  claim 66 , wherein the blades comprise a porous sintered material configured to direct a transpiration fluid to an exterior surface of the blades.