The invention relates to a power plant (1) for generating electric energy (100) and process steam (200), comprising: a gas turbine (2) for driving a first generator (3) in order to generate electric energy (100) by combusting a fuel into flue gas (300), a steam turbine (4) for driving a second generator (5) in order to generate electric energy (100), comprising a first stage (4a) for converting fresh steam (400) into residual steam (201), which constitutes at least part of the process steam (200), and a waste heat steam generator (6) for generating the fresh steam (400) from fresh water (500) using the exhaust heat of the flue gas (300), wherein the residual steam (201) has a residual steam pressure which is lower than the pressure of the fresh steam (400), the waste heat steam generator (6) comprises a pre-heater (7) for pre-heating the fresh water (500) in order to form feed water (600) and an evaporator (8) for evaporating the feed water (600) in order to form the fresh steam (400), and the feed water (600) has a feed water pressure which is higher than the residual steam pressure. The invention is characterized by a throttle valve (9, 14) for expanding part of the feed water (600) either at the residual steam pressure in order to generate an additional steam (202) or at a drive steam pressure which is lower than the residual steam pressure in order to generate a drive steam (700) for operating a second stage (4b) of the steam turbine (4).

Steam generators in power plants exchange energy from a primary medium to a secondary medium for energy extraction. Steam generators include one or more primary conduits and one or more secondary conduits. The conduits do not intermix the mediums and may thus discriminate among different fluid sources and destinations. One conduit may boil feedwater while another reheats steam for use in lower and higher-pressure turbines, respectively. Valves and other selectors divert steam and/or water into the steam generator or to other turbines or the environment for load balancing and other operational characteristics. Conduits circulate around an interior perimeter of the steam generator immersed in the primary medium and may have different cross-sections, radii, and internal structures depending on contained. A water conduit may have less flow area and a tighter coil radius. A steam conduit may include a swirler and rivulet stopper to intermix water in any steam flow.

A turbine shaft bearing apparatus in a turbine module includes two axially spaced turbine shaft bearings, including an outlet side bearing protected from overheating by a solid bearing housing which surrounds the outlet side bearing. The bearing housing being provided with a support including conduit for a lubricating medium. The turbine module has plurality of axially spaced turbine wheels connected to a common turbine shaft and coaxial therewith; an inlet through which motive fluid vapor is introduced to a first stage of the turbine wheels; a structured bleeding exit opening formed in an outer turbine casing of the turbine module; and a passage defined between two of the turbine wheels and in fluid communication with the bleeding exit opening, wherein expanded motive fluid vapor may be extracted through the structured bleeding exit opening and supplied to a heat exchange component for heating the motive fluid condensate.

A turbine shaft bearing apparatus in a turbine module includes two axially spaced turbine shaft bearings, including an outlet side bearing protected from overheating by a solid bearing housing which surrounds the outlet side bearing. The bearing housing being provided with a support including conduit for a lubricating medium. The turbine module has plurality of axially spaced turbine wheels connected to a common turbine shaft and coaxial therewith; an inlet through which motive fluid vapor is introduced to a first stage of the turbine wheels; a structured bleeding exit opening formed in an outer turbine casing of the turbine module; and a passage defined between two of the turbine wheels and in fluid communication with the bleeding exit opening, wherein expanded motive fluid vapor may be extracted through the structured bleeding exit opening and supplied to a heat exchange component for heating the motive fluid condensate.

The present application relates to an exhaust steam waste heat recovering and supplying system used for air-cooling units in large thermal power plants. Each of the two steam turbines has independent exhaust steam extraction system, and the exhaust steam extraction system of each steam turbine is connected with corresponding pre-condenser to heat the return water of the heating network. The exhaust steam extraction system of each steam turbine is further connected with the corresponding steam ejector; the exhaust port of each steam is connected with the corresponding steam ejector condenser to heat the return water of the heating network. The exhaust steam waste heat of the air-cooling units in a thermal power plant can be recycled in high efficiency to improve the utility rate of the exhaust steam, increase heating capacity, reduce cold end loss to the largest extent, and maximize the energy saving benefits.

The present application relates to an exhaust steam waste heat recovering and supplying system used for air-cooling units in large thermal power plants. Each of the two steam turbines has independent exhaust steam extraction system, and the exhaust steam extraction system of each steam turbine is connected with corresponding pre-condenser to heat the return water of the heating network. The exhaust steam extraction system of each steam turbine is further connected with the corresponding steam ejector; the exhaust port of each steam is connected with the corresponding steam ejector condenser to heat the return water of the heating network. The exhaust steam waste heat of the air-cooling units in a thermal power plant can be recycled in high efficiency to improve the utility rate of the exhaust steam, increase heating capacity, reduce cold end loss to the largest extent, and maximize the energy saving benefits.

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 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.

This combined cycle gas turbine plant has a gas turbine (104) and a steam turbine (106) mounted on the same shaft. A control system is configured for switching the plant from a rated mode of operation, in which the plant is operated on gas turbine output and steam turbine output, to a reduced load mode of operation, in which the plant is operated on gas turbine output alone. The switch from the rated mode of operation to the reduced load mode of operation occurs if plant demand decreases below a predetermined threshold. The steam turbine is run under full speed no load conditions in the reduced load mode of operation, and is heated using controlled steam admission, to maintain the steam turbine in a heated stand-by state.

Steam generators in power plants exchange energy from a primary medium to a secondary medium for energy extraction. Steam generators includes one or more primary conduits and one or more secondary conduits. The conduits do not intermix the mediums and may thus discriminate among different fluid sources and destinations. One conduit may boil feedwater while another reheats steam for use in lower and higher-pressure turbines, respectively. Valves and other selectors divert steam and/or water into the steam generator or to other turbines or the environment for load balancing and other operational characteristics. Conduits circulate around an interior perimeter of the steam generator immersed in the primary medium and may have different cross-sections, radii, and internal structures depending on contained. A water conduit may have less flow area and a tighter coil radius. A steam conduit may include a swirler and rivulet stopper to intermix water in any steam flow.