A coal fired oxy boiler power plant is disclosed in which a steam coil oxygen preheater located on an oxygen line Air Separation Unit is thermally integrated with the condensate system. Thermal energy for the steam coil oxygen preheater is provided via an extraction line connected to a steam extraction port of an intermediate pressure steam turbine. A drain line of the steam coil oxygen preheater fluidly connects the steam coil oxygen preheater to a point of the Rankine steam cycle fluidly within the condensate system.

A coal fired oxy boiler power plant is disclosed in which a steam coil oxygen preheater located on an oxygen line Air Separation Unit is thermally integrated with the condensate system. Thermal energy for the steam coil oxygen preheater is provided via an extraction line connected to a steam extraction port of an intermediate pressure steam turbine. A drain line of the steam coil oxygen preheater fluidly connects the steam coil oxygen preheater to a point of the Rankine steam cycle fluidly within the condensate system.

In a method for controlling a waste heat recovery steam generator of the once-through steam generator type in a combined cycle power plant, the flow volume of the feedwater into the steam generator is controlled based on a measured steam temperature at the outlet of a superheater and on a set-point value for the steam temperature for a steam turbine. A degree of superheating at the outlet of a high-pressure evaporator, a degree of subcooling at the inlet into the high-pressure evaporator, and the measured current flow volume of the feedwater are integrated in the control system in a plurality of control steps. For an optimum operation during rapid load changes, the method especially comprises additional controlling of the degree of subcooling of the flow medium at the inlet into the high-pressure evaporator.

A system using hybrid Rankine cycles is provided. The system includes a first Rankine cycle system using a first working fluid, the first system producing exergy loss and residual energy from at least one of turbine extraction, turbine condensation and boiler flue gas; and a second Rankine cycle system using a second working fluid to recover the exergy loss and residual energy. The second working fluid comprises a first stream and a second stream, wherein the first stream exchanges heat with the first system via at least one first heat exchanger, and the second stream exchanges heat with the first system via the at least one first heat exchanger and at least one second heat exchanger. A turbine of the first system is configured to allow the first working fluid to exit at a sufficiently high pressure and temperature to provide heat to the second system instead of expanding to a low pressure and temperature and discharging heat to ambient using a condenser.

A system using hybrid Rankine cycles is provided. The system includes a first Rankine cycle system using a first working fluid, the first system producing exergy loss and residual energy from at least one of turbine extraction, turbine condensation and boiler flue gas; and a second Rankine cycle system using a second working fluid to recover the exergy loss and residual energy. The second working fluid comprises a first stream and a second stream, wherein the first stream exchanges heat with the first system via at least one first heat exchanger, and the second stream exchanges heat with the first system via the at least one first heat exchanger and at least one second heat exchanger. A turbine of the first system is configured to allow the first working fluid to exit at a sufficiently high pressure and temperature to provide heat to the second system instead of expanding to a low pressure and temperature and discharging heat to ambient using a condenser.

A steam power plant is suggested having, parallel to the high-pressure preheater passage (VW4 to VW6), a heat reservoir (A) which is loaded with preheated condensate in weak-load times. This preheated condensate is taken from the heat reservoir (A) for generating peak-load and inserted downstream of the high-pressure preheater passage (VW4 to VW6) into the condensate line (19.2) resp. the feed water container (8). Thus it is possible to quickly control the power generation of the power plant in a wide range without significantly having to change the heating output of the boiler of the steam generator (1). A steam power plant equipped according to the invention can thus be operated with bigger load modifications and also provide more control energy.

A steam power plant is suggested having, parallel to the high-pressure preheater passage (VW4 to VW6), a heat reservoir (A) which is loaded with preheated condensate in weak-load times. This preheated condensate is taken from the heat reservoir (A) for generating peak-load and inserted downstream of the high-pressure preheater passage (VW4 to VW6) into the condensate line (19.2) resp. the feed water container (8). Thus it is possible to quickly control the power generation of the power plant in a wide range without significantly having to change the heating output of the boiler of the steam generator (1). A steam power plant equipped according to the invention can thus be operated with bigger load modifications and also provide more control energy.

The present invention relates to a system and a method for providing steam. In particular, the present invention relates to a steam delivery system comprising a thermal energy storage apparatus for heating a flow of feedwater to produce steam at a predetermined temperature and/or a predetermined pressure.

The present invention relates to a system and a method for providing steam. In particular, the present invention relates to a steam delivery system comprising a thermal energy storage apparatus for heating a flow of feedwater to produce steam at a predetermined temperature and/or a predetermined pressure.