Abstract: A vertical type once-through heat recovery steam generator (HRSG) capable of improving operational stability during rapid startup and lifetime of a steam turbine while reducing environmental pollution caused by emissions, and a combined power generation system including the HRSG are provided. The HRSG includes a medium-pressure section including a medium-pressure side desuperheater installed at the rear of a medium-pressure superheater to lower the temperature of the steam supplied to a medium-pressure steam turbine, and a high-pressure section including a high-pressure side desuperheater installed at the rear of a high-pressure superheater to lower the temperature of the steam supplied to a high-pressure steam turbine.

Abstract: A method for controlling carryover in a chemical recovery boiler. The method comprises feeding black or brown liquor to a furnace of the chemical recovery boiler through an injection gun to burn the black or brown liquor. The chemical recovery boiler comprises a bullnose, which narrows the furnace, and a first superheater, of which at least a part is arranged at a higher vertical level than the bullnose. The method comprises measuring information indicative of a spatial temperature distribution on a cross section of the furnace, wherein the cross section is above the injection gun and below the first superheater; determining primary information indicative of carryover using the information indicative of the spatial temperature distribution on the cross section of the furnace; and controlling a temperature of the black or brown liquor that is fed to the furnace using the primary information. In addition, a system for performing the method.

Abstract: A steam generator for generating a superheated fluid from a working fluid using a stream of heated gas, the steam generator comprising: a housing, which defines a gas flow path having an inlet at one, upstream end thereof into which a stream of heated gas is delivered and an outlet at the other, downstream end thereof; and a steam generation module which is disposed within the gas flow path of the housing, the steam generation module comprising a heat exchanger which receives a working fluid and is operative to raise the temperature of the working fluid to provide a saturated fluid, and a superheater which receives the saturated fluid from the heat exchanger and is operative to raise the temperature of the saturated fluid and provide a supersaturated fluid.

Abstract: An enhanced steam cycle utilizing a dual pressure recovery boiler with reheat. A dual pressure designed recovery boiler furnace is provided with a lower furnace and an upper furnace. The lower furnace is operated at a lower temperature to prevent or reduce corrosion of the lower furnace wall tubes. The lower furnace can be either a low pressure natural circulation steam generating (drum) system or economizer. The upper furnace operates as a high pressure natural circulation steam generating (drum) system, or as a once-through supercritical steam generating system at higher temperatures and pressures permitting implementation of higher efficiency reheat steam cycles.

Abstract: The invention relates to a method and an apparatus for the generation of superheated steam. According to the invention, essentially saturated or wet steam is generated in a main vessel in which superheating is technically not possible or only restrictedly possible and which is superheated in an auxiliary plant whereby the superheater of the auxiliary plant is controlled dependent upon the steam production of the main plant.

Abstract: A dual pressure boiler system has a bottom furnace that operates as a low pressure natural circulation steam generating system and a top furnace that operates as a high pressure natural circulation steam generating system. The low pressure natural circulation steam generating system has a low pressure steam drum, a first pump for providing feed water to the low pressure steam drum, and a low pressure superheater fluidly connected to the low pressure steam drum. The high pressure natural circulation steam generating system has a high pressure steam drum, a second pump for providing feed water to the high pressure steam drum, and a high pressure superheater fluidly connected to the high pressure steam drum.