A steam generator includes a shroud and an annular stepwise helical baffle extending along at least part of a length of the shroud. There is a riser located in a central region of the steam generator. The helical baffle is made up of at least one annular sector of flat plates. The edges of the flat plates may be straight or corrugated.

Arrangement for supporting U-bend tube sections in the high heat environment of steam generators using flat bars. The invention uses a combination of thicker and thinner flat bars to impart a serpentine path to the arc of the normally curvilinear U-tubes. The support system accommodates the dilation and contraction of coolant tubes and other elements caused by the extreme and varying conditions inside a steam generator, and which can cause gaps between coolant tubes and prior art tube support bars. Bars of alternating thickness provide alternating offsets to tensionally push and support each tube on multiple sides and in multiple locations, and this tension keeps the tubes in contact with at least some flat bars on multiple sides regardless of size and shape changes. Support arrangement includes a set of fan bars, each fan bar including thick and thin flat bars projecting up and out from a collector bar.

The present invention provides a passive residual heat removal system and an atomic power plant comprising the same, the passive heat removal system comprising: a plate-type heat exchanger for causing heat exchange between a primary system fluid or a secondary system fluid which, in order to remove sensible heat from an atomic reactor cooling material system and residual heat from a reactor core, has received the sensible heat and the residual heat, and a cooling fluid which has been introduced from outside of a containment unit; and circulation piping for connecting the atomic reactor cooling material system to the plate-type heat exchanger, thereby forming a circulation channel of the primary system fluid, or connecting a steam generator, which is arranged at the boundary between the primary and secondary systems, to the plate-type heat exchanger, thereby forming a circulation channel of the secondary system fluid.

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.

In an illustrative embodiment, a pressurized water nuclear reactor (PWR) includes a pressure vessel (12, 14, 16), a nuclear reactor core (10) disposed in the pressure vessel, and a vertically oriented hollow central riser (36) disposed above the nuclear reactor core inside the pressure vessel. A once-through steam generator (OTSG) (30) disposed in the pressure vessel includes vertical tubes (32) arranged in an annular volume defined by the central riser and the pressure vessel. The OTSG further includes a fluid flow volume surrounding the vertical tubes and having a feedwater inlet (50) and a steam outlet (52). The PWR has an operating state in which feedwater injected into the fluid flow volume at the feedwater inlet is converted to steam by heat emanating from primary coolant flowing inside the tubes of the OTSG, and the steam is discharged from the fluid flow volume at the steam outlet.

A quenching system for a plant, operating a cracking furnace, works with liquid as well as gaseous starting materials. The quenching system includes a primary heat exchanger (PQE 10) and a secondary heat exchanger (SQE 11) and a tertiary heat exchanger. A TLX-D exchanger (TLX-D 26) is arranged and configured as the tertiary heat exchanger for dual operation. The TLX-D (26) is connected in series via a TLX-D gas feed line (24) to the SQE 11. The TLX-D (26) is connected to a steam drum (59), which is connected to a feed water line (49), via a TLX-D feed water drain line (34) and a TLX-D riser (46) and a TLX-D downcomer (38). The SQE 11 is connected to the steam drum (59), which is connected to the feed water line (49), via a TLX downcomer (52) and a TLX-riser (57).

Embodiments provide a combustion structure that can achieve stable combustion by addressing the aforementioned drawbacks in the prior art such as low flame stability, backfire, deflagration, blockage and/or any other drawbacks. The combustion chamber structure in accordance with the disclosure can include: a grate structure including a first set of elongated components, a fire retention structure including a second set of elongated components. The first set of first elongated components can be arranged along an axial direction within the combustion chamber structure. The second set of elongated components can be arranged along the axial direction in a same direction as the first elongated components. The second set of elongated components can be configured to generate a negative pressure zone within the combustion chamber. The first set of elongated components can form apertures that can be aligned with apertures formed by the second set of elongated components.

A quenching system for a plant, operating a cracking furnace, works with liquid as well as gaseous starting materials. The quenching system includes a primary heat exchanger (PQE 10) and a secondary heat exchanger (SQE 11) and a tertiary heat exchanger. A TLX-D exchanger (TLX-D 26) is arranged and configured as the tertiary heat exchanger for dual operation. The TLX-D (26) is connected in series via a TLX-D gas feed line (24) to the SQE 11. The TLX-D (26) is connected to a steam drum (59), which is connected to a feed water line (49), via a TLX-D feed water drain line (34) and a TLX-D riser (46) and a TLX-D downcomer (38). The SQE 11 is connected to the steam drum (59), which is connected to the feed water line (49), via a TLX downcomer (52) and a TLX-riser (57).

A method for producing work is disclosed. The method includes increasing the pressure of a working fluid including carbon dioxide from a first pressure at least equal to a triple point pressure to a second pressure above the triple point pressure. The method also includes heating the working fluid, extracting mechanical work by expanding a first portion of the heated working fluid to a third pressure, supplying a second portion of the heated working fluid as a motive fluid to an ejector, increasing the pressure of the expanded working fluid by supplying the expanded working fluid to the ejector to combine with the motive fluid and form an output fluid at the fourth pressure, the fourth pressure at least equal to the triple point pressure of the working fluid. The method also includes refrigerating the output fluid to condense a vapor phase into a liquid phase.

A method for producing work is disclosed. The method includes increasing the pressure of a working fluid including carbon dioxide from a first pressure at least equal to a triple point pressure to a second pressure above the triple point pressure. The method also includes heating the working fluid, extracting mechanical work by expanding a first portion of the heated working fluid to a third pressure, supplying a second portion of the heated working fluid as a motive fluid to an ejector, increasing the pressure of the expanded working fluid by supplying the expanded working fluid to the ejector to combine with the motive fluid and form an output fluid at the fourth pressure, the fourth pressure at least equal to the triple point pressure of the working fluid. The method also includes refrigerating the output fluid to condense a vapor phase into a liquid phase.