EP-4739891-A1 - CONDENSING STEAM TURBINE PLANT, AND METHODS FOR OPERATING SUCH A CONDENSING STEAM TURBINE PLANT

Abstract

The invention relates to a condensing steam turbine plant (1) comprising at least one steam turbine (2), a water-cooled condenser (3) which can be connected to the exhaust steam of the steam turbine (2), and a further heat condenser (4) which can be connected to the exhaust steam of the steam turbine (2). The heat condenser (4) is arranged on the steam side parallel to the water-cooled condenser (3), wherein the water-cooled condenser (3) has an accumulation control means (5) for the condensate, by which the available heat exchanger surface area (6) of the water-cooled condenser (3) can be adapted via the water level of the condensate in the water-cooled condenser (3). Furthermore, the invention relates to methods for operating a condensing steam turbine plant (1) of this type.

Inventors

• AMERSBACH, Stefan

Assignees

• Siemens Energy Global GmbH & Co. KG

Dates

Publication Date

20260513

Application Date

20240719

Claims (4)

1. 1. Condensation steam turbine plant (1) comprising at least one steam turbine (2), a water-cooled condenser (3) connectable to the exhaust steam of the steam turbine (2), and a further heating condenser (4) connectable to the exhaust steam of the steam turbine (2), characterized in that the heating condenser (4) is arranged on the steam side parallel to the water-cooled condenser (3) and the water-cooled condenser (3) has a build-up control (5) for the condensate, by means of which the available heat exchanger surface (6) of the water-cooled condenser (3) can be adjusted via the water level of the condensate in the water-cooled condenser (3).
2. 2. Condensation steam turbine plant according to claim 1, characterized in that the heating condenser (4) interacts with a district heating network (7) and can transfer heat of the exhaust steam to the district heating network (7).
3. 3. Method for operating a condensing steam turbine plant (1) according to claim 1 or 2, characterized in that the amount of heat supplied to the heating condenser (4) is regulated by increasing the water level (8) in the water-cooled condenser (3) by accumulating the condensate, whereby the heat exchanger surface (6) of the water-cooled condenser (3) is reduced, which leads to an increased exhaust steam pressure, whereby the amount of exhaust steam to the heating condenser (4) is increased.
4. 4. Method for operating a condensing steam turbine plant (1) according to claim 1 or 2, characterized in that the amount of heat supplied to the heating condenser (4) is regulated by the water level (8) in the water-cooled Condenser (3) is reduced, whereby the heat exchanger surface (6) of the water-cooled condenser (3) is increased, which leads to a reduced exhaust steam pressure, whereby the exhaust steam quantity to the heating condenser (4) is reduced.

Description

Description Condensation steam turbine plant and method for operating such a steam turbine plant The invention relates to a condensing steam turbine plant, hereinafter also referred to as steam turbine plant for the sake of simplicity, according to the preamble of independent patent claim 1, as well as to methods for operating such a steam turbine plant according to independent patent claims 3 and 4. In order to increase the overall efficiency of a steam turbine plant, steam turbine plants often have, in addition to the water-cooled condenser for condensing the exhaust steam, one (or more) heating condensers, via which the waste heat from the steam can be used for heating purposes. A typical application is the feeding of heat into a district heating/heating network. The steam turbine plant should be able to meet the flexible needs of the district heating/heating network all year round and/or alternatively be able to discharge the exhaust steam to the water-cooled condenser. In general, two variants for heat generation using heating condensers have become established on the market: If an existing system is designed for pure condensation, the waste heat from the exhaust steam cannot be used and is released into the environment via the cooling water. The heating condensers are supplied with steam via intermediate steam extraction at the turbine and the energy is transferred to the district heating network. If there is an existing system that is designed as a back-pressure system, the waste heat can only be used if the district heating network can absorb the heat. If no other heat consumers are involved, the system must be shut down and electricity production is also eliminated. In order to achieve greater flexibility, solutions with parallel operation of condenser and heating condenser have been implemented in the past, but as an "EITHER-OR" solution. Many operators decided to switch from pure condensation operation to pure heating condensation operation when the heating network reached a certain level of demand. However, this requires that the heat-absorbing system (e.g. district heating network) can also absorb the heat. Furthermore, the steam turbine must be shut down and then restarted after the switchover process. Another possible, partially flexible solution is to throttle the exhaust steam mass flow to the water-cooled condenser using a control element (control flap or control valve). The disadvantage of this solution is the increased space requirement and the use of additional, costly fittings, the flexibility of which is often limited by the controllable range (e.g. minimum opening angle for flaps, etc.) and, in pure condensation operation, the reduced system efficiency due to the increased pressure loss in the exhaust steam section. An object of the present invention is therefore to provide a steam turbine plant in which waste heat can be dissipated flexibly and continuously either to the water-cooled condenser (cooling medium: cooling water) or to the heating condenser (cooling medium: heating water). A further object of the invention is to provide methods for operating such a steam turbine plant . The problem is solved with regard to the steam turbine plant by the features of independent patent claim 1 and with regard to the methods by the features of independent patent claims 3 and 4. Further advantages and embodiments of the invention, which can be used individually or in combination with one another, are the subject of the dependent claims. The condensation steam turbine system according to the invention comprising at least one steam turbine, a water-cooled condenser that can be connected to the exhaust steam of the steam turbine and a further heating condenser that can be connected to the exhaust steam of the steam turbine is characterized in that the heating condenser is arranged on the steam side parallel to the water-cooled condenser and the water-cooled condenser has a build-up control for the condensate, by means of which the available heat exchanger surface of the water-cooled condenser can be adjusted via the water level of the condensate in the water-cooled condenser. The exhaust steam from the steam turbine is connected to both the water-cooled condenser and the heating condenser via an exhaust steam channel and/or pipes in a common pressure chamber (without shut-off). By accumulating the condensate in the water-cooled condenser, the heating surface of the water-cooled condenser can be reduced and thus the exhaust steam pressure can be increased, whereby the amount of exhaust steam flowing to the heating condenser can be flexibly and continuously regulated. The heat exchangers must be designed/constructed for such a "damming control" or, in the case of existing systems, may need to be adapted. The variable weight (condenser + damming condensate) caused by the damming must also be taken into account in the installation concept and the static and dynamic calculations. The basic require