Abstract: A heat recovery steam generator (“HRSG”) 40, which is closely coupled to a gas turbine, includes a flow controls structural array 10 disposed upstream of the tubes 42 of the HRSG 40. The structural array 10 is formed of a plurality of grate-like panels 18 secured to horizontal supports 24 mounted to the support structure of the HRSG 40. The structural array 10 diffuses the high velocity exhaust stream 14 exiting the gas turbine and redistributes the gas flow evenly throughout the HRSG 40. The structural array 10 reduces wear and damage of the tubes 46.

Abstract: In a nozzle and a nozzle assembly, for use in a pressure vessel, stress analysis is used to determine areas of stress concentration. The nozzle is configured to reduce these stress concentrations.

Abstract: An evaporator 10 for evaporating a liquid includes a plurality of harps 20 disposed within a duct or chamber such that a heated fluid flow 22 (e.g., heated gas or flue gas) passes through each successive row of harps 20 of the evaporator 10. Each of the harps 20 includes a lower header 24, a plurality of lower tubes 26, an intermediate equalizing chamber 28, a plurality of upper tubes 30, and an upper header 32. The lower tubes 30 are in fluid communication with the lower header 24 and extend upward vertically from the lower header. The upper ends of the lower tubes 26 are in fluid communication with the equalizing chamber 28. The upper tubes 30 are in fluid communication with the equalizing chamber 28 and extend upward vertically from the equalizing chamber. The upper ends of the upper tubes 30 are in fluid communication with the upper header 32.

Abstract: A heat recovery steam generator that includes a first steam drum for receiving a flow of water and steam from an evaporator. The first steam drum is adapted to provide the flow of water and steam to a second steam drum. The second steam drum is in fluid communication with the first steam drum and receives the flow of water and steam from the first steam drum and separates steam from the flow of water and steam to form a separated steam. There is a steam flow outlet positioned in the second steam drum, the steam flow outlet adapted to release the separated steam from the second steam drum.

Abstract: A radial nozzle assembly for use in a pressure vessel to enable fluid flow through the vessel wall is provided. The radial nozzle assembly has a nozzle and a cup-shaped flange extending from one end of the nozzle. The nozzle has a bore disposed therethrough along its length to permit fluid flow through the wall of the pressure vessel. The flange is defined by a generally cup or dome-shaped wall having an open end. The nozzle assembly is secured to the wall of the vessel such that the nozzle is disposed in a radial orientation to the flange and possibly in a horizontal orientation.

Abstract: An evaporator for steam generation is presented. The evaporator includes a plurality of primary evaporator stages and a secondary evaporator stage. Each primary stage includes one or more primary arrays of heat transfer tubes, an outlet manifold coupled to the arrays, and a downcomer coupled to the manifold. Each of the primary arrays has an inlet for receiving a fluid and is arranged transverse to a flow of gas through the evaporator. The gas heats the fluid flowing through the arrays to form a two phase flow. The outlet manifold receives the two phase flow from the arrays and the downcomer distributes the flow as a component of a primary stage flow. One or more of the plurality of primary evaporator stages selectively form the primary stage flow from respective components of the two phase flow, and provide the primary stage flow to inlets of the secondary evaporator stage.

Abstract: System and method for pre-startup or post-shutdown preparation for such power plants are disclosed which are subject to frequent startups and shutdowns, such as a solar operated power plant. The system and method introduces an auxiliary fluid flow to be circulated in an opposite direction to a direction of normal working fluid flow responsible for producing electricity. That is, if the working fluid flow in a first direction for operating the power plant, than the auxiliary fluid flows in a second direction, opposite to the first direction. The auxiliary fluid flows in the second direction for a predetermined time and at a predetermined conditions through a plurality of superheater panel arrangements of solar receiver former to activation of the working fluid circuit, as pre-startup preparation of the power plant, and after cessation of the working fluid circuit, as post-shutdown preparation of the power plant, to attain predetermined conditions in the superheater.

Abstract: System and method for pre-startup or post-shutdown preparation for such power plants are disclosed which are subject to frequent startups and shutdowns, such as a solar operated power plant. The system and method introduces an auxiliary fluid flow to be circulated in an opposite direction to a direction of normal working fluid flow responsible for producing electricity. That is, if the working fluid flow in a first direction for operating the power plant, than the auxiliary fluid flows in a second direction, opposite to the first direction. The auxiliary fluid flows in the second direction for a predetermined time and at a predetermined conditions through a plurality of superheater panel arrangements of solar receiver former to activation of the working fluid circuit, as pre-startup preparation of the power plant, and after cessation of the working fluid circuit, as post-shutdown preparation of the power plant, to attain predetermined conditions in the superheater.

Abstract: A radial nozzle assembly for use in a pressure vessel to enable fluid flow through the vessel wall is provided. The radial nozzle assembly has a nozzle and a cup-shaped flange extending from one end of the nozzle. The nozzle has a bore disposed therethrough along its length to permit fluid flow through the wall of the pressure vessel. The flange is defined by a generally cup or dome-shaped wall having an open end. The nozzle assembly is secured to the wall of the vessel such that the nozzle is disposed in a radial orientation to the flange and possibly in a horizontal orientation.

Abstract: In a nozzle and a nozzle assembly, for use in a pressure vessel, stress analysis is used to determine areas of stress concentration. The nozzle is configured to reduce these stress concentrations.

Abstract: An evaporator system comprises an evaporator; a drum; and a pump that are in fluid communication with each other. The pump is operative to create a temporary pressure gradient during start-up of an evaporator system and transport a fluid from the evaporator to the drum prior to the fluid reaching its boiling point in the evaporator. Following the fluid reaching its boiling point in the evaporator, the fluid naturally circulates in the evaporator system.

Abstract: A heat recovery steam generator that includes a first steam drum for receiving a flow of water and steam from an evaporator. The first steam drum is adapted to provide the flow of water and steam to a second steam drum. The second steam drum is in fluid communication with the first steam drum and receives the flow of water and steam from the first steam drum and separates steam from the flow of water and steam to form a separated steam. There is a steam flow outlet positioned in the second steam drum, the steam flow outlet adapted to release the separated steam from the second steam drum.

Abstract: An evaporator for steam generation is presented. The evaporator includes a plurality of primary evaporator stages and a secondary evaporator stage. Each primary stage includes one or more primary arrays of heat transfer tubes, an outlet manifold coupled to the arrays, and a downcomer coupled to the manifold. Each of the primary arrays has an inlet for receiving a fluid and is arranged transverse to a flow of gas through the evaporator. The gas heats the fluid flowing through the arrays to form a two phase flow. The outlet manifold receives the two phase flow from the arrays and the downcomer distributes the flow as a component of a primary stage flow. One or more of the plurality of primary evaporator stages selectively form the primary stage flow from respective components of the two phase flow, and provide the primary stage flow to inlets of the secondary evaporator stage.

Abstract: A method of controlling stress in a boiler pressure vessel comprises limiting the diameter of a drum (10) of the boiler pressure vessel and preheating at least a portion of the wall (12) of the drum (10). Limiting the diameter of the drum (10) allows pressure in the drum (10) to be increased for a given mechanical stress. Furthermore, preheating the wall (12) of the drum (10) reduces peak thermally induced stresses in a material from which the drum (10) is fabricated.

Abstract: A heat recovery steam generator (“HRSG”) 40, which is closely coupled to a gas turbine, includes a flow controls structural array 10 disposed upstream of the tubes 42 of the HRSG 40. The structural array 10 is formed of a plurality of grate-like panels 18 secured to horizontal supports 24 mounted to the support structure of the HRSG 40. The structural array 10 diffuses the high velocity exhaust stream 14 exiting the gas turbine and redistributes the gas flow evenly throughout the HRSG 40. The structural array 10 reduces wear and damage of the tubes 46.

Abstract: An evaporator 10 for evaporating a liquid includes a plurality of harps 20 disposed within a duct or chamber such that a heated fluid flow 22 (e.g., heated gas or flue gas) passes through each successive row of harps 20 of the evaporator 10. Each of the harps 20 includes a lower header 24, a plurality of lower tubes 26, an intermediate equalizing chamber 28, a plurality of upper tubes 30, and an upper header 32. The lower tubes 30 are in fluid communication with the lower header 24 and extend upward vertically from the lower header. The upper ends of the lower tubes 26 are in fluid communication with the equalizing chamber 28. The upper tubes 30 are in fluid communication with the equalizing chamber 28 and extend upward vertically from the equalizing chamber. The upper ends of the upper tubes 30 are in fluid communication with the upper header 32.

Abstract: A material feed apparatus 34 for influencing the travel properties of a feed stream of material 42 moving between a pulverizer 14 and a furnace 12 includes a feed path 36 passing through an upstream passage periphery UPZ. The feed path 36 includes one duct 44A having a branch entry 66A and another branch duct 44C having a branch entry 66C both downstream of the upstream passage periphery UPZ through which the feed stream of the material 42 travels in two segregated portions. A Y-axis drive assembly 58 and the X-axis drive assembly 62 move the nozzle 52 relative to the reference axis RA, whereupon the upstream passage periphery UPZ moves relative to the reference axis RA such that the travel properties of the one portion of material in the one branch duct 44A are different than its travel properties before the movement of the upstream passage periphery UPZ.

Abstract: A material feed apparatus 34 for influencing the travel properties of a feed stream of material 42 moving between a pulverizer 14 and a furnace 12 includes a feed path 36 passing through an upstream passage periphery UPZ. The feed path 36 includes one duct 44A having a branch entry 66A and another branch duct 44C having a branch entry 66C both downstream of the upstream passage periphery UPZ through which the feed stream of the material 42 travels in two segregated portions. A Y-axis drive assembly 58 and the X-axis drive assembly 62 move the nozzle 52 relative to the reference axis RA, whereupon the upstream passage periphery UPZ moves relative to the reference axis RA such that the travel properties of the one portion of material in the one branch duct 44A are different than its travel properties before the movement of the upstream passage periphery UPZ.

Abstract: A splitter plate arrangement is provided for controlling the flow of flue gas in a vertical stack. The splitter plate arrangement 100 is operable to control the flow of flue gas in a vertical stack 128 having an annular entry 130 communicated with two inlets 126A, 126B which each communicate a respective one of the flue gas producers with the vertical stack 128. The inlets 126A, 126B are both disposed on a common inlet axis which bisects the annular entry 130 into two bisected halves, the two inlets 126A, 126B are oriented in opposition to one another such that the inlet flow 132 of flue gas through the inlet 126A flows in a direction opposite to the inlet flow 134 of flue gas through the inlet 126B. The splitter plate arrangement 100 includes a first splitter plate 136 and a second splitter plate 138.

Abstract: An air compartment of a corner windbox of a tangential firing system of a fossil fuel-fired furnace for injecting secondary air into the furnace. The air compartment includes a channel portion with an entrance end communicating with an air delivery duct and an exit end communicating via an exit assembly with the furnace opening. The exit assembly includes at least one vane for guiding an air stream and a mounting frame for supporting the vane relative to the channel portion for guiding thereby of an air stream passing from the channel portion through the furnace opening into the furnace. The vane includes a surface portion which intersects the horizontal plane at an acute angle and a pair of opposed transverse edges. The vane and the mounting frame are disposed within the channel portion such that the leading edge of the vane is upstream of the furnace opening.