A method of operating a combined heat and power plant includes, when there is insufficient heat removal from a hot flue gas downstream from a hot flue gas generator but upstream of a steam evaporator, as a result of insufficient mass flow of imported steam to a steam superheater, to prevent the hot flue gas temperature downstream of the steam superheater from rising to or above a predetermined limit, quenching steam inside the steam superheater or quenching steam being fed to the steam superheater by injecting boiler feed water or condensate into the steam to produce steam in the steam superheater. The quenching increases the removal of heat from the hot flue gas and reduces the hot flue gas temperature downstream of the steam superheater to ensure that the hot flue gas temperature downstream of the steam superheater does not rise to or above the predetermined limit.

A combined cycle turbine plant having at least one gas turbine, a steam turbine and at least one waste heat steam generator. The waste heat steam generator has at least one condensate pre-heater into which a condensate line discharges, and has a feed water pre-heater which is connected upstream of the condensate pre-heater in the flow direction of a gas turbine flue gas and upstream of which, on the feed water side, there is connected a feed water pump, and which is connected to a fuel preheating unit for the gas turbine. From the fuel preheating unit a line for cooled feed water discharges into a motive medium inlet of a jet pump of which the suction medium inlet is connected to an outlet of the condensate pre-heater and of which the outlet is connected to the condensate line. A corresponding method recirculates condensate in a combined cycle turbine plant.

A method of operating a combined heat and power plant (10) (CHP plant) includes generating hot flue gas and cooling the hot flue gas in a sequence of cooling steps to recover heat and to generate steam in a heat recovery steam generator (16) (HRSG). The HRSG (16) includes an LP steam evaporator (36) designed to generate steam at least over a pressure range of from 2 bar(g) to 18 bar(g) so that either LP steam or MP steam can selectively be generated by the LP steam generator (36), thereby to cool the hot flue gas, and an MP steam superheater (24) upstream of the LP steam evaporator (36) to superheat MP steam in heat exchange with the hot flue gas thereby to cool the hot flue gas. The method further includes, when no or insufficient MP steam is being imported to the MP steam superheater (24) to ensure safe operation of the MP steam superheater, and/or when a demand exists for exporting MP steam which cannot be satisfied by imported MP steam superheated in the MP steam superheater (24), and/or when a demand exists for MP steam in the CHP plant which cannot be satisfied by imported MP steam, operating the LP steam evaporator (36) at an operating pressure in the range of between 8 bar(g) and 18 bar(g) to generate MP steam to wet the MP steam superheater (24) and/or to satisfy at least to some extent said demand for MP steam, and thereafter, when sufficient MP steam is being imported to the MP steam superheater (24) from external of the CHP plant (10) to ensure safe operation of the MP steam superheater (24), and/or when any demand for exported MP steam is satisfied by imported MP steam which is superheated in the MP steam superheater (24) and then exported, and/or when there is no more demand for exporting of MP steam, and/or when the demand for MP steam in the CHP plant (10) is being satisfied at least to some extent by imported MP steam, reducing the operating pressure of the LP steam evaporator (36) to a pressure in the range of between 2 bar(g) and 8 bar(g) thereby to generate LP steam.

Integration of an oxyfuel combustion boiler at elevated pressures and a heat exchanger is achieved to produce carbon dioxide by feeding flue gas comprising carbon dioxide and water from the oxyfuel combustion boiler to a direct contact cooler column wherein water is condensed at a temperature of 0 to 10 C. lower than its dew point; feeding a portion of the condensed water from the direct contact cooler column to the oxyfuel combustion boiler; feeding a portion of the carbon dioxide from the direct contact cooler column to the oxyfuel combustion boiler; and recovering a portion of the carbon dioxide from the direct contact cooler column.

A turbine engine assembly includes a core engine that generates an exhaust gas flow, a condenser where water is extracted from the exhaust gas flow, an evaporator where heat is input into the water that is extracted by the condenser to generate a first steam flow, a first steam turbine where the first steam flow is expanded and cooled to generate a first cooled flow, a bypass passage that defines a path for the first steam flow around the first steam turbine, and a superheater where at least one of the first steam flow and the first cooled flow is reheated to generate a second steam flow.

A method and an apparatus for detecting breakage of piping, the method including the steps of: closing an outlet of heat exchanger tubes with an outlet-side shutoff valve; supplying high-temperature water into the heat exchanger tubes with a desalinated water pump; closing an inlet of the heat exchanger tubes with an inlet-side main shutoff valve and an inlet-side auxiliary shutoff valve with the heat exchanger tubes filled with the high-temperature water; and determining breakage of the heat exchanger tubes based on a change in the pressure of the high-temperature water in the heat exchanger tubes with the inlet and the outlet closed.

The present disclosure relates to cogeneration of power and one or more chemical entities through operation of a power production cycle and treatment of a stream comprising carbon monoxide and hydrogen. A cogeneration process can include carrying out a power production cycle, providing a heated stream comprising carbon monoxide and hydrogen, cooling the heated stream comprising carbon monoxide and hydrogen against at least one stream in the power production cycle so as to provide heating to the power production cycle, and carrying out at least one purification step so as to provide a purified stream comprising predominately hydrogen. A system for cogeneration of power and one or more chemical products can include a power production unit, a syngas production unit, one or more heat exchange elements configured for exchanging heat from a syngas stream from the syngas production unit to a stream from the power production unit, and at least one purifier element configured to separate the syngas stream into a first stream comprising predominately hydrogen and a second stream.

The present invention relates to a gas-steam combined cycle centralized heat supply device and a heat supply method. The gas-steam combined cycle centralized heat supply device comprises a gas-steam combined cycle system connected with a thermal station through a heating network return water heating system; the gas-steam combined cycle system comprises a gas turbine connected with a direct contact type flue gas condensation heat exchanger and a steam turbine via a waste heat boiler; the thermal station comprises a hot water type absorption heat pump and a water-water heat exchanger; the heating network return water heating system comprises a steam type absorption heat pump for recovering flue gas waste heat and a steam-water heat exchanger. The present invention can be widely applied to the industry of power plant waste heat recovery.

The present application provides a power generation system. The power generation system may include a gas turbine engine, a steam turbine, and a steam turbine preheating system. The steam turbine preheating system may include a steam generator that creates a flow of steam to preheat the steam turbine from an extraction of the gas turbine engine.

The invention refers to a CCPP comprising a gas turbine, a water steam cycle with a steam turbine and a HRSG with at least two pressure levels, and a fuel preheater for preheating the fuel of the gas turbine. The fuel preheater includes a first heat exchanger for preheating the fuel to a first elevated temperature, which is connected to a feed water line from a pressure level of the HRSG, which is below the highest HRSG pressure level, and a second heat exchanger for further preheating the fuel gas to a second elevated temperature, which is connected to the high pressure feed water with the highest pressure level of the HRSG. The disclosure further refers to a method for operating a CCPP with such a fuel preheater.