RU2116599C1 - Steam-turbine plant heat-transfer system - Google Patents

Abstract

FIELD: thermal engineering. SUBSTANCE: system has mixing condenser 1, barometric coolant and condensate drain pipe 2 communicating with water trap 3, circulating pump 4 with pressure conduit 5 supplying water to wash cooling tower 6 with pond 7 and overflow sill 8. Channel 9 provides communication between overflow sill 8 and water trap 3; pressure conduit 5 is connected to line incorporating flow controller 10 that operates in response to pulse coming from level gage in water trap 3. EFFECT: improved reliability of heat-transfer system. 1 dwg

Description

 The invention relates to a power system and can be used in steam turbine plants with mixing type condensers in rotary cooling systems, in particular in geothermal steam turbine installations.

 Known systems for removing heat from steam turbine plants, consisting of a mixing condenser, condensate pump, wet cooling tower and circulation pump (see Shklover G.G., Milman O.O. Research and calculation of condensing devices of steam turbines. -M .: Energoatomizdat, 1985 , p. 240).

 In some cases, to exclude from the condensate pump circuit, barometric drainage of condensate into the catchment and the supply of water from this catchment to the cooling tower using a circulation pump are used; from the cooling tower pool to the mixing condenser - by gravity due to the pressure difference between the atmosphere and the condenser (see Prgecto Geotermiko San-Jacinto, Dal, Spa Milan, 1993).

 The main disadvantage of such a scheme is the need to maintain a balance of costs between the pump from the water collector to the cooling tower, from the cooling tower to the condenser and from the condenser to the water collector. This requires the installation of a flow regulator on the discharge line of the circulation pump in the cooling tower, while the size of the regulator is determined by the large diameters of the circulating water pipelines, and its failure leads to an emergency stop of the entire steam turbine unit. In addition, the regulator must operate with a certain pressure drop across it, which leads to significant additional power costs for pumping cooling water.

 The purpose of the invention is to increase the reliability of the heat removal system and reduce energy costs for pumping water.

 The essence of the invention lies in the fact that an overflow threshold is set in the cooling tower basin, beyond which there is a channel for draining excess water from the cooling tower basin to the water collector, and a line for draining or supplying water to the circulating water supply system with a flow regulator is connected to the discharge pipe of the circulation pump for whose work is changing the level in the catchment.

As a result of these essential features, the heat removal system acquires the following new properties:
1. Increased reliability when the level regulator fails.

 2. Reducing energy consumption for the own needs of the power plant.

 In FIG. 1 shows a heat removal system, it includes a mixing condenser 1, a pipe for barometric drainage of cooling water and condensate 2 in the water intake 3, a circulation pump 4 with a pressure pipe 5 for supplying water to the wet cooling tower 6 with a pool 7 and an overflow threshold 8 is connected to the water collector Channel 9 connects the overflow threshold 8 to the catchment 3, and a line with a flow regulator 10 is connected to the pressure pipe, the pulse for which is taken by the level sensor 11 in the catchment 3.

 The heat removal system operates as follows. The circulation pump 4 delivers water to the cooling tower 6, where it is cooled and discharged into the pool 7, from it, due to the pressure difference, the cooled water enters the mixing condenser 1, the mixture of cooling water and steam condensate is discharged through a barometric pipe into the catchment 3. Pump 4 is selected so that it exceeds the maximum possible flow rate of water from the pool 7 to the condenser 1. The excess water through the overflow threshold 8 through channel 9 is discharged back into the catchment 3. If the total mass of water in the cooling system is increased If this is characteristic (this is typical for geothermal steam turbine plants), then the level in the catchment increases and, based on the impulse from the level sensor 11, controller 10 discharges excess water from the system.

 If there is a lack of water in the cooling system (due to evaporation and entrainment from the tower in conventional steam turbines), then the level in the water collector drops and the regulator 10, based on the pulse of the sensor 11, makes up the system.

 By using the combination of the above design solutions, the flow controller 10 is installed on the drain line of excess water, the flow rate on this line and its cross section is several orders of magnitude (50 - 1000 times) less than the pressure line 5, the failure of the regulator does not stop the turbine, since it stands on a branch from the main thread. The required pump head is reduced in comparison with the case when the regulator is on the pressure pipe, this significantly reduces the energy consumption for pumping water.

Claims (1)

 The heat removal system from the steam turbine installation, consisting of a mixing condenser with a pipe for barometric discharge into the water collector, a circulation pump connected to it with a pressure pipe for supplying water to the wet tower, from the pool of which water enters the mixing condenser, characterized in that in the cooling tower basin an overflow threshold and a channel are established for draining excess water from the pool to the catchment, and a supply or drain line is connected to the pressure pipe of the circulation pump water with a flow regulator, which is controlled by the pulse from the level sensor in the catchment.