RU2328603C1 - Method of heat power plant operation - Google Patents

Abstract

FIELD: heating.

SUBSTANCE: invention is designed to utilise heat from blow-off water and can be used in heat power engineering. Generated in boiler, steam is supplied to steam turbine, and additives accumulated in boiler water are drained from boiler together with blow-off water. Blow-off water is used as heating medium in water-to-water heat exchanger. Feed water being supplied to boiler will be heated in regenerating heaters by steam resulted from turbine bleeding. Condensate from the last in feed water line high pressure regenerating heater is used as medium heated in heat exchanger connected to blow-off water pipeline. After condensate heating in water heat exchanger, it is pumped into feed water pipeline between the first and second stages of boiler feed water heater.

EFFECT: improvement of heat power plants operation economy and ecology.

1 dwg

Description

The invention relates to the field of power engineering and can be used in thermal power plants.

A known method of operation of a thermal power plant, in which the steam generated in a steam boiler is supplied to a steam turbine, impurities accumulated in the boiler water is removed from the boiler with purge water, which is used as a heating medium in a water-water heat exchanger, the feed water supplied to the boiler is heated by steam turbine extraction in regenerative heaters, characterized in that as the heated medium of the heat exchanger connected to the purge water pipeline, condensate of the latter is used along the feed hot water of the regenerative high-pressure heater, and after heating this condensate in a water-to-water heat exchanger, it is pumped to the feed water pipe between the first and second stages of the boiler economizer (see Patent No. 2227828 “Method of operation of a thermal power plant”, IPC ⁷ F01K 13/00, B.I. 2004. No. 12).

The disadvantages of this method are reduced ecology and savings in the operation of a thermal power plant due to the incomplete use of mass and high potential heat of purge water, the need to use special equipment for its disposal — continuous purge separators and heat exchangers-coolers and pollution of surface water bodies with mineralized effluents.

The technical result achieved by the present invention is to improve the ecology and economy of the thermal power plant by utilizing the high potential to reduce the heat of purge water without the use of continuous purge separators.

To achieve this result, a method of operating a thermal power plant is proposed, in which the steam generated in a steam boiler is fed to a steam turbine, mineral impurities accumulated in the boiler water are removed from the boiler with purge water. The feed water supplied to the boiler is heated by steam extraction of the turbine in regenerative heaters.

The difference of the proposed method is that as the heated medium of the heat exchanger connected to the purge water pipeline, condensate of the latter in the course of the feed water of the high pressure regenerative heater is used, and after heating this condensate in the water-water heat exchanger, it is pumped into the feed water pipe between the first and the second steps of the boiler economizer.

A new set of features of the method allows you to achieve the desired technical result due to the maximum possible use of the high potential of the heat of the purge water and the reduction due to this fuel consumption at the thermal power station, as well as by eliminating the purge water from the separator circuit and connecting the regenerative heater to heat the condensate of the latter along the feed water of the regenerative high-pressure heater by a sufficiently large amount, since the purge costs water and condensate are comparable in magnitude. Since the consumption of condensate is many times less than the consumption of feed water, the capital costs for installing a water-to-water heat exchanger are significantly reduced compared to the prototype and the scope of application of the claimed solution expands.

Information confirming the possibility of carrying out the invention with obtaining the above technical result are as follows.

The drawing shows a diagram of a thermal power plant in which the proposed method is implemented.

The thermal power station contains a steam turbine (1) connected by a steam line (2) of sharp steam to a steam stake (3), to which a purge water pipe (4) and feed water pipe (5) included in the regenerative feed pipe (5) are connected high pressure heaters (6), which are connected through a heating medium to the steam extraction of the turbine, and a water-to-water heat exchanger (7) connected via a heated medium to the condensate pipe of the last high pressure regenerative heater (6) along the feed water, and the pipeline of condensate of this heater heated by purge water after the water-to-water heat exchanger is fed through the pump (8) to the feed water pipe (5) between the first (9) and second (10) stages of the economizer.

The method consists of the following operations.

The steam boiler (3) generates steam, which through the steam line (2) of the hot steam enters the steam turbine (1). Feed water to the steam boiler (3) is fed through the feed water pipe (5) through high pressure regenerative heaters (6). Feed water is heated in regenerative high-pressure heaters (6) by steam extraction of a turbine. Mineral impurities accumulated in the boiler water of the steam boiler (3) are continuously discharged from the boiler drum through the purge water pipe (4) with purge water, which is sent to the water-water heat exchanger (7), where it is used as a heating medium. In the water-water heat exchanger (7), the condensate of the last high-pressure regenerative heater (6) is heated along the feed water, which is fed into the feed pipe (5) between the first (9) and second (10) stages using a pump (8) economizer. New features make it possible to use the high potential of the purge water heat to heat one of the feed water flows of the condensate of the last high-pressure heater by a sufficiently large amount with minimal capital costs.

Thus, the proposed method of operation of a thermal power plant allows to improve the ecology and economy of its work due to the full use of the high potential of the heat of the purge water and the simplification of the scheme of the thermal power plant due to the exclusion of special equipment of a typical scheme for the utilization of purge water - separators and heat exchangers-coolers.

Claims (1)

The method of operation of a thermal power plant, in which the steam generated in a steam boiler is fed into a steam turbine, impurities accumulated in the boiler water are discharged from the boiler with purge water, which is used as a heating medium in a water-water heat exchanger, the feed water supplied to the boiler is heated by steam turbines in regenerative heaters, characterized in that as a heated medium connected to the purge water pipe of the heat exchanger, condensate of the latter is used along the feed water s of a regenerative high-pressure heater, and after heating this condensate in a water-to-water heat exchanger, it is pumped into the feed water pipe between the first and second stages of the boiler economizer.