A system and method for warmkeeping a steam generator such as a sub-critical steam generator is disclosed. Water extraction piping extracts water from a component of one of the water fill circuits of the sub-critical steam generator. A deaerator heating system having an inventory tank of water mixes the extracted water with the water in the tank, and heats the mix of water to a predetermined temperature level to generate heated deaerated feedwater. Feedwater piping forwards the heated deaerated feedwater at the predetermined temperature level from the deaerator heating system to the water fill circuits of the sub-critical steam generator. The water extraction piping, the deaerator heating system and the feedwater piping operate cooperatively to warmkeep the water fill circuits in accordance with the predetermined temperature level while the sub-critical steam generator is in the unfired stand-by mode of operation.

A method for improving the efficiency of a fired heater without an air preheat system is described. The method involves the use of an additional outboard convection section which is separate from the regular convection section of the fired heater. The outboard convection section uses the boiler feed water or an alternate cold sink to reduce the temperature of the flue gas, thereby improving the efficiency.

A method for improving the efficiency of a fired heater without an air preheat system is described. The method involves the use of an additional outboard convection section which is separate from the regular convection section of the fired heater. The outboard convection section uses the boiler feed water or an alternate cold sink to reduce the temperature of the flue gas, thereby improving the efficiency.

A method for improving the efficiency of a fired heater without an air preheat system is described. The method involves the use of an additional outboard convection section which is separate from the regular convection section of the fired heater. The outboard convection section uses the boiler feed water or an alternate cold sink to reduce the temperature of the flue gas, thereby improving the efficiency.

A method for improving the efficiency of a fired heater without an air preheat system is described. The method involves the use of an additional outboard convection section which is separate from the regular convection section of the fired heater. The outboard convection section uses the boiler feed water or an alternate cold sink to reduce the temperature of the flue gas, thereby improving the efficiency.

A steam direct injection injector and direct injection heater assembly. The injector defines an enclosure having an upstream end that is constructed to receive a steam fluid flow and a plurality of radially oriented orifices that are configured to distribute and inject the steam into a surrounding fluid. A seat is disposed proximate a downstream end of the injector and a movable plug or modulating component is disposed within the enclosure proximate the seat. A biasing element is disposed between the seat and the modulating component and configured to interact with the seat and the modulating component to allow selective exposure of a second heating section without obstructing a first heating section that are defined by the radially oriented orifices of the injector.

A spray nozzle and a deaerator each include an external cylinder provided with a plurality of jetting outlets on an outer circumference portion thereof, an inner cylinder that is supported inside the external cylinder so as to be movable in an axial center direction and is provided with a plurality of first communication holes capable of communicating with the jetting outlets, and an open-close valve that includes a shaft coupled to the inner cylinder and a valve body provided at a distal end portion of the shaft and capable of opening and closing a distal opening of the external cylinder. The spray nozzle and the deaerator thus structured provide improved performance by preventing an increase in pressure loss occurring regardless of a jet flow amount.

A spray nozzle and a deaerator each include an external cylinder provided with a plurality of jetting outlets on an outer circumference portion thereof, an inner cylinder that is supported inside the external cylinder so as to be movable in an axial center direction and is provided with a plurality of first communication holes capable of communicating with the jetting outlets, and an open-close valve that includes a shaft coupled to the inner cylinder and a valve body provided at a distal end portion of the shaft and capable of opening and closing a distal opening of the external cylinder. The spray nozzle and the deaerator thus structured provide improved performance by preventing an increase in pressure loss occurring regardless of a jet flow amount.

A steam power generating system includes at least one steam generator, at least one turbine assembly, at least one electric generator, at least one condenser and a feedwater preheat arrangement including at least one injection feedwater heater connected to the condenser and the turbine assembly. The injection feedwater heater includes a main heater body and at least one injection nozzle. A predetermined amount of condensate water from the condenser is arranged to be pumped into the main heater body. The condensate water passing through the water inlet is arranged to be injected into a heat exchange compartment through the injection nozzle for creating a negative pressure in the heat exchange compartment. The negative pressure draws a predetermined amount of steam from the turbine assembly to enter the heat exchange compartment for mixing with the condensate water.

An injection feedwater heater for a steam power generating system includes at least one main heater body and at least one injection nozzle. The main heater body has at least one heat exchange compartment, at least one water inlet, at least one steam inlet, and at least one water outlet formed on the main heater body. The injection nozzle is provided in the main heater body at a position adjacent to the water inlet, wherein a predetermined amount of condensate water is arranged to be pumped into the main heater body through the water inlet. The condensate water passing through the water inlet is arranged to be injected into the heat exchange compartment through the injection nozzle for creating a negative pressure in the heat exchange compartment. The negative pressure drawing a predetermined amount of steam to enter the heat exchange compartment for mixing with the condensate water.