Power system with enhanced thermodynamic efficiency and pollution control
An elevated pressure power plant ( 100 ) for cleanly and efficiently oxidizing, gasifying or combusting a fuel. The fuel is oxidized or gasified in a reaction chamber ( 210 ) at a pressure range from approximately 700 psia to 2000 psia, or from approximately 850 psia to 1276 psia. Products of combustion from the chamber may be passed to a heat exchanger ( 224 ). A portion of the condensed water may be recycled to the products of combustion upstream of the heat exchanger. Also, before being passed to the reaction chamber, the coolant may be routed through the heat exchanger in a two-step pressure fashion.
1. A method of operating a power plant, comprising:
passing a fossil fuel into a combustion chamber;
passing an oxidant into said combustion chamber, said oxidant comprising oxygen and carbon dioxide;
combusting said fossil fuel within said combustion chamber at a first pressure, said first pressure being substantially within a range of from approximately 700 psia to approximately 2000 psia; and
passing a coolant having a heat exchange relationship with said combusting fossil fuel and a heat sink having a first temperature;
said first pressure being equal to or greater than a liquid-vapor equilibrium pressure of carbon dioxide at said first temperature of said heat sink;
passing products of partial combustion from said combustion chamber to a heat exchanger;
condensing water from said products of partial combustion at a second pressure within said heat exchanger, said second pressure being selected so that said water condenses from said products of partial combustion at a temperature above approximately 450° F.; and
passing said products of partial combustion to a boiler.
2. A method of operating a power plant, comprising:
passing a fossil fuel into a combustion chamber;
passing an oxidant into said combustion chamber, said oxidant comprising oxygen and carbon dioxide;
combusting said fossil fuel within said combustion chamber at a first pressure, said first pressure being substantially within a range of from approximately 700 psia to approximately 2000 psia; and
passing a coolant having a heat exchange relationship with said combusting fossil fuel and a heat sink having a first temperature;
said first pressure being equal to or greater than a liquid-vapor equilibrium pressure of carbon dioxide at said first temperature of said heat sink;
passing products of partial combustion from said combustion chamber to a heat exchanger;
condensing water from said products of partial combustion at a second pressure within said heat exchanger, said second pressure being selected so that said water condenses from said products of partial combustion at a temperature above approximately 450° F.; and
passing said products of partial combustion to a gas turbine.
3. A method of operating a power plant, comprising:
passing a fossil fuel into a combustion chamber;
passing an oxidant into said combustion chamber, said oxidant comprising oxygen and carbon dioxide;
combusting said fossil fuel within said combustion chamber at a first pressure, said first pressure being substantially within a range of from approximately 700 psia to approximately 2000 psia; and
passing a coolant having a heat exchange relationship with said combusting fossil fuel and a heat sink having a first temperature;
said first pressure being equal to or greater than a liquid-vapor equilibrium pressure of carbon dioxide at said first temperature of said heat sink;
passing products of partial combustion from said combustion chamber to a heat exchanger;
condensing water from said products of partial combustion at a second pressure within said heat exchanger, said second pressure being selected so that said water condenses from said products of partial combustion at a temperature above approximately 450° F.; and
passing said products of partial combustion to a combined cycle power plant.
4. A method of operating a power plant, comprising:
passing a fossil fuel into a combustion chamber;
passing an oxidant into said combustion chamber, said oxidant comprising oxygen and carbon dioxide;
combusting said fossil fuel within said combustion chamber at a first pressure, said first pressure being substantially within a range of from approximately 700 psia to approximately 2000 psia; and
passing a coolant having a heat exchange relationship with said combusting fossil fuel and a heat sink having a first temperature;
said first pressure being equal to or greater than a liquid-vapor equilibrium pressure of carbon dioxide at said first temperature of said heat sink;
passing products of partial combustion from said combustion chamber to a heat exchanger;
condensing water from said products of partial combustion at a second pressure within said heat exchanger, said second pressure being selected so that said water condenses from said products of partial combustion at a temperature above approximately 450° F.; and
passing said products of partial combustion to a chemical synthesis plant.