CN112435767A

CN112435767A - Condensate water circulating device for nuclear power station

Info

Publication number: CN112435767A
Application number: CN202011296141.4A
Authority: CN
Inventors: 杨霞
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-02-17
Filing date: 2020-02-17
Publication date: 2021-03-02
Also published as: CN112432156B; CN111302539B; CN111302539A; CN112432156A

Abstract

The invention discloses a condensed water circulating device for a nuclear power station, which is connected with a secondary circulating pump and a condensing tank, wherein the circulating device comprises a filter tank, a liquid storage tank, a waste liquid tank and a shunt pipe group, the filter tank comprises a tank body, a filter layer is arranged at the bottom of the tank body, an overflow port is arranged on the side surface of the tank body, the outer end of the overflow port is positioned above the liquid storage tank, the bottoms of the filter layer, the waste liquid tank and the condensing tank are all connected onto the shunt pipe group, and the side surface of the bottom of the. In the shunt tube group: the tee joint is respectively connected with one end of a water inlet pipe, a sewer pipe and a siphon pipe, the other end of the water inlet pipe is connected to the bottom of the tank body, the other end of the sewer pipe is connected to the bottom of the condensate tank, the siphon pipe is a section of pipe body which ascends first and then descends, the highest point of the siphon pipe is higher than the overflow port and lower than the bottom of the condensate tank, the lowest point of the siphon pipe is lower than the bottom of the filter tank, a vacuum breaking pipe is arranged from the highest point of the siphon pipe to the.

Description

Condensate water circulating device for nuclear power station

Technical Field

The invention relates to the field of condensed water circulating equipment, in particular to a condensed water circulating device for a nuclear power station.

Background

In a general power generation system of a nuclear power station, a primary circulation system and a secondary circulation system are provided, the primary circulation system is a part where a reactor is located, the part also comprises a main heat exchanger, a primary circulation pump and a primary circulation pipe, the part is surrounded by thick concrete, heat in the reactor is transferred in the main heat exchanger through the primary circulation pipe, the secondary circulation system is a system where a steam turbine and a generator are located, the secondary circulation pipe is also provided, a condensation tank on a path is cooled into liquid by water communicated by a condensation pipe and is pumped and circulated through the secondary circulation pump, two acting machines, namely the secondary circulation pump and the steam turbine, are arranged on the path, and steam can possibly hook some rust or metal objects on the inner wall of the pipeline on the flowing path and can also be mixed with some organic impurities such as bearing lubricating oil on the secondary circulation pump and the steam turbine, these impurities mixed with steam or condensed water may reach the main heat exchanger if not treated, and if accumulated or scaled in the main heat exchanger, the impurities are troublesome to clean.

In the prior art, a proper circulating filtration system is not available, only a better material which is not easy to corrode is selected to be used for building a circulating pipeline, and the sealing performance of lubricating oil of a circulating pump and a steam turbine is also a big article, although the effects of rust prevention and doping prevention can be achieved, impurities still can be mixed into circulating water after long-term use, and then the impurities reach all parts on the circulating pipeline, particularly a main heat exchanger, so that scaling damage is caused.

Disclosure of Invention

The invention aims to provide a condensate water circulating device for a nuclear power station, which aims to solve the problems in the prior art.

In order to achieve the purpose, the invention provides the following technical scheme:

the utility model provides a condensate circulating device for nuclear power station, connects second grade circulating pump and condensate tank, and condensate circulating device is including filtering jar, liquid storage pot, waste liquid jar and reposition of redundant personnel nest of tubes, filters the jar including a jar body, and jar body bottom is equipped with the filter layer, jar side is equipped with the overflow mouth, and the outer end of overflow mouth is located the liquid storage pot top, and filter layer bottom, waste liquid jar and condensate tank bottom all connect on reposition of redundant personnel nest of tubes, and liquid storage pot bottom side is connected to the second grade circulating pump.

The filtering is realized by adding a component with a filtering function between the condensing tank and the secondary circulating pump, a filtering layer is arranged in the filtering tank, condensed water flowing down from the condensing tank passes through the filtering layer from bottom to top, impurities insoluble in water are filtered and accumulated in the shunt pipe group, when the impurities and the like are accumulated in a large amount, water body at the part below an overflow port in the filtering tank passes through the filtering layer from top to bottom, the impurities are washed down and discharged to the waste liquid tank through the shunt pipe group, and the waste liquid tank is treated periodically.

Furthermore, the shunt tube group comprises a water inlet tube, a tee joint, a sewer pipe and a siphon pipe, the tee joint is respectively connected with one end of the water inlet tube, the sewer pipe and one end of the siphon pipe, the other end of the water inlet tube is connected with the bottom of the tank body, the other end of the sewer pipe is connected to the bottom of the condensation tank, the siphon pipe is a section of pipe body which ascends first and then descends, the highest point of the siphon pipe is higher than the overflow port and lower than the bottom of the condensation tank, the lowest point of the siphon pipe is lower than the bottom of the filter tank, a vacuum breaking tube.

The water inlet pipe, the sewer pipe and the siphon pipe are respectively connected to the tee joint, the tee joint becomes the intersection of the main circulation and the waste liquid discharge, because the highest position of the siphon pipe is positioned between the overflow port and the bottom of the condensation tank, under the normal flowing state, the water body from the bottom of the condensation tank flows out from the overflow port through the water inlet pipe, the filter layer and the tank body to form a low-resistance preferential path, when more impurities are filtered in the filter layer, the resistance of the water flow passing through the filter layer can be increased, so that the flow resistance from the bottom of the condensation tank to the overflow port is slowly increased, when the water flow is increased to exceed the bottom of the condensation tank to the highest point of the siphon pipe, the highest point of the siphon pipe is fully piled with liquid, when the liquid passes through the siphon pipe and begins to fall at the descending section, because the lowest end of the siphon is lower than the filter tank, the siphon is established, the liquid flowing reversely washes away the sundries accumulated in the filter layer, when the sundries mixed into the condensed water on the pipeline of the secondary circulating system and the working machine are not much, but the main heat exchanger is sensitive to the sundries, a thinner filter layer can be selected, so that the back washing can be carried out as long as a little sundries are filtered off in the filter layer, and the fine sundries are prevented from passing through the filter layer. When the water level in the filtering tank is reduced to the bottom end of the broken hollow pipe inserted into the tank body, the gas in the filtering tank reaches the highest point of the siphon pipe through the broken hollow pipe, and the siphon is broken.

Furthermore, the condensed water circulating device also comprises a cover frame, the cover frame wraps the filter tank, the liquid storage tank, the waste liquid tank and the flow dividing pipe group to form a closed space, a connecting pipeline between the liquid storage tank and the secondary circulating pump penetrates through the wall surface of the cover frame, a connecting pipeline between the flow dividing pipe group and the condensing tank penetrates through the wall surface of the cover frame, inert gas is filled in the cover frame, and a vacuum pump or a compressor is arranged on the wall surface of the cover frame to adjust the environment pressure inside the cover frame.

The pressure when condensate water is discharged from the condensing tank is probably not atmospheric pressure according to the parameter requirement of a power generation system, so if the design pressure at the position is higher than the atmospheric pressure, the condensate water is directly discharged in an open liquid storage tank to lose larger energy, a secondary circulating pump needs to do larger work to pump the condensate water into a main heat exchanger, and the condensate water is directly exposed in the air and possibly doped with dissolved oxygen, so that the heat exchange of the circulating water in the main heat exchanger is not facilitated, and the oxidation corrosion in the main heat exchanger can be caused. If the design pressure there is lower than atmospheric pressure, the flow of the condensed water in the filter tank will be affected, but instead, the reflux of atmospheric air into the condenser tank from bottom to top via the shunt tube group should not occur. Therefore, in order to match the pressure of the condensed water discharged by the condensing tank under different design conditions, the filter tank, the liquid storage tank, the waste liquid tank and the shunt pipe group are wrapped by a cover frame, and the proper environmental pressure is constructed by a vacuum pump or a compressor on the wall surface, so that the condensed water can flow in and among the tank bodies conveniently. The liquid level pressure of the waste liquid tank and the environmental pressure at the overflow port need to be correspondingly matched to meet the siphon condition.

Furthermore, an electrode is arranged on the water inlet pipe. The electrode can carry out electrolytic separation on metal ions and acid radical ions in the condensed water to enable the metal ions and the acid radical ions to become metal objects and gas molecules, the metal objects are filtered by the filter layer, and the gas molecules are separated out from the water body and are collected to the high point position of the siphon. Therefore, the condensed water passing through the water inlet pipe and the filter layer is purer.

Furthermore, an on-off valve is arranged on the sewer pipe, a material level sensor is arranged on the highest point wall surface of the siphon pipe, and the material level sensor is electrically connected with the on-off valve.

During the siphon process, the connection between the condensing tank and the tee joint is preferably disconnected, otherwise, a large amount of water is discharged from the sewer pipe when the siphon occurs until the siphon is disconnected, and the water is also discharged to the waste liquid tank through the siphon pipe, but the water only contains a small amount of impurities and is not wasted. Therefore, the on-off valve is arranged on the sewer pipe to be switched on and off, the level sensor is arranged at the top of the siphon pipe and detects whether water exists at the position, and when the position exists in the water, the siphon process is indicated to be in progress, so that a signal is given to close the on-off valve and disconnect the sewer pipe from the sewer pipe, after the siphon is finished, liquid does not exist at the highest position of the siphon pipe any more, the on-off valve is opened again, and the sewer pipe downwards discharges condensed water.

Preferably, the downcomer and the siphon descending section are internally provided with fine-hole tube cores. When the siphon pipe and the downcomer are thick, gas is accumulated in the shunt pipe group, and the gas accumulated at the top of the siphon pipe cannot be exhausted during the siphoning process, because the liquid which flows upwards from the tee joint passes through the highest point of the siphon pipe and then flows downwards, the gas cannot be completely extruded downwards on the thick pipeline, the gas can be dispersed into bubbles and floats upwards, and is always accumulated above the siphon pipe, therefore, a pore pipe core is arranged in the flow descending section of the downcomer and the siphon pipe, the pore pipe core is a flow pipe formed by honeycomb-shaped thin pipes, the water cannot push upwards the water body under the thinner pipe diameter due to the surface viscous effect, and then the gas in the siphon pipe can be fully exhausted during the siphoning process, including gas molecules generated by electrode electrolyte acid radical ions, and it should be noted that the flow of the gas in the broken pipe should flow in a single direction, that is, it is preferable that the flow of oxygen, carbon dioxide, etc. in the siphon tube is prevented from reaching the inside of the canister through the hollow tube by only flowing from the canister to the siphon tube, not flowing in both directions,

preferably, the waste liquid tank is filled with oxygen absorption liquid, and comprises a discharge pipe extending outwards from the bottom or the side surface of the main tank, and the discharge pipe at least has a flow direction of inlet and outlet.

The waste liquid tank wrapped by the cover frame is inconvenient to discharge waste liquid, so that the waste liquid is discharged through a pipeline, a closed environment is built by the cover frame, liquid sealing is carried out on the bottom end of the siphon pipe through the containing oxygen absorption liquid in the waste liquid tank, and gas molecules such as the waste liquid discharged by the siphon pipe and oxygen are absorbed by the oxygen absorption liquid, so that the waste liquid is prevented from diffusing into the space in the cover frame, and the waste liquid reaches the liquid storage tank.

Further, high-temperature steam is introduced from the outside into the water inlet pipe. The condensed water discharged from the condensing tank is often in an unsaturated state, more gas is dissolved in the unsaturated state, and after the condensed water is mixed by high-temperature steam, the condensed water is adjusted to be saturated water under the local environmental pressure, so that more dissolved gas can be precipitated and collected in the siphon, and the subsequent condensed water is purer.

For the flowing continuity of the water body in the secondary circulating system, two parts of the parts contained in the cover frame are arranged and run in parallel, and the flow rate is adjusted and stabilized through the secondary circulating pump.

Compared with the prior art, the invention has the beneficial effects that: according to the invention, the liquid flowing down from the condensing tank is subjected to shunting treatment through the filter tank, the liquid storage tank and the waste liquid tank, the filtering layer filters the liquid flowing conventionally, pure condensed water overflows from an overflow port and falls into the liquid storage tank, and the condensed water in the liquid storage tank is pumped by the secondary circulating pump to carry out power generation circulation; when more impurities are accumulated on the filter layer, the liquid level of the ascending section of the siphon pipe continuously ascends until the liquid level exceeds the highest point, after the liquid level exceeds the highest point, siphon is established, the liquid in the filter tank reversely flows through the filter layer, and the impurities are washed away, so that the filtering process of the next period is carried out; the electrode in the water inlet pipe removes metal ions and acid radical ions in the condensed water, makes the metal ions and the acid radical ions in the condensed water in a molecular state and separate out the condensed water, and the condensed water is collected in the water inlet pipe and the siphon pipe and is discharged to the waste liquid tank in the siphon process.

Drawings

In order that the present invention may be more readily and clearly understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings.

FIG. 1 is a simplified schematic diagram of a power generation cycle for a nuclear power plant;

FIG. 2 is a schematic diagram of the basic structure of the present invention;

FIG. 3 is a schematic diagram of the structure of the present invention with a fine-meshed tube core, a cover frame, electrodes and a level meter;

FIG. 4 is a schematic flow diagram of the present invention during a normal cycle;

FIG. 5 is a schematic flow diagram of the present invention in a filtration and deslagging state.

In the figure: 1-filter tank, 11-tank body, 12-filter layer, 13-overflow port, 2-liquid storage tank, 3-waste liquid tank, 31-discharge pipe, 4-shunt pipe group, 41-water inlet pipe, 42-tee joint, 43-sewer pipe, 44-siphon pipe, 49-pore pipe core, 5-on-off valve, 6-broken empty pipe, 71-cover frame, 72-electrode, 73-level meter, 8-secondary circulation system, 81-steam turbine, 82-generator, 83-condensation tank, 84-condensation pipe, 85-secondary circulation pump, 86-secondary circulation pipe, 9-primary circulation system, 91-reactor, 92-main heat exchanger, 93-primary circulation pump and 94-primary circulation pipe.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1 and 2, a condensate water circulating device for a nuclear power station is connected with a secondary circulating pump 85 and a condensing tank 83, the condensate water circulating device comprises a filtering tank 1, a liquid storage tank 2, a waste liquid tank 3 and a shunt pipe group 4, the filtering tank 1 comprises a tank body 11, a filtering layer 12 is arranged at the bottom of the tank body 11, an overflow port 13 is arranged on the side surface of the tank body 11, the outer end of the overflow port 13 is positioned above the liquid storage tank 2, the bottoms of the filtering layer 12, the bottoms of the waste liquid tank 3 and the condensing tank 83 are connected on the shunt pipe group 4, and the side surface of the.

In a typical power generation system of a nuclear power plant, there are a primary circulation system 9 and a secondary circulation system 8, the primary circulation system 9 is a part where a reactor 91 is located, the part is further provided with a main heat exchanger 92, a primary circulation pump 93 and a primary circulation pipe 94, the part is surrounded by thick concrete, heat generated in the reactor 91 is transferred to the main heat exchanger 92 through the primary circulation pipe 94, the secondary circulation system 8 is a system where a steam turbine 81 and a generator 82 are located, the secondary circulation pipe 86 is further provided, a condensation tank 83 on a path is cooled to a liquid state by water supplied from a condensation pipe 84, and is pumped and circulated through a secondary circulation pump 85, because the pipeline is long and two working machines, namely the secondary circulation pump 85 and the steam turbine 81, are present on the path, steam may be mixed with some rust or metal objects on the inner wall of the pipeline on the flow path, and some organic impurities such as bearing lubricating oil on the secondary circulation pump 85 and the turbine 81, after the impurities are mixed into steam or condensed water, the impurities can reach the main heat exchanger 92 if not treated, and if the impurities are accumulated or scaled in the main heat exchanger 92, the impurities are very troublesome to clean, and the impurities on the secondary circulation are filtered out in a filtering mode to prevent the impurities from reaching the main heat exchanger 92.

As shown in fig. 2, the filtering is realized by adding a component with filtering function between the condensing tank 83 and the secondary circulating pump 85, the filtering layer 12 is arranged in the filtering tank 1, the condensed water flowing down from the condensing tank 83 passes through the filtering layer 12 from bottom to top, the impurities insoluble in water are filtered and accumulated in the shunt tube group 1, when the impurities and the like are accumulated in a large amount, the water body below the overflow port 13 in the filtering tank 1 passes through the filtering layer 12 from top to bottom, the impurities are washed down and discharged to the waste liquid tank 3 through the shunt tube group 4, and the waste liquid tank 3 is periodically treated.

As shown in fig. 2, the shunt tube group 4 includes a water inlet tube 41, a tee joint 42, a downcomer 43 and a siphon 44, the tee joint 42 is respectively connected with one end of the water inlet tube 41, the downcomer 43 and the siphon 44, the other end of the water inlet tube 41 is connected with the bottom of the tank body 11, the other end of the downcomer 43 is connected with the bottom of the condensation tank 83, the siphon 44 is a section of tube which ascends and then descends, the highest point of the siphon 44 is higher than the overflow port 13 and lower than the bottom of the condensation tank 83, the lowest point of the siphon 44 is lower than the bottom of the filter tank 1, a vacuum breaking tube 6 is arranged from the highest point of the siphon 44 to the inside of.

The water inlet pipe 41, the downcomer 43 and the siphon 44 are respectively connected to the tee joint 42, the tee joint 42 becomes the junction of the main circulation and the waste liquid discharge, because the highest position of the siphon 44 is located between the overflow port 13 and the bottom of the condensation tank 83, under the normal flow state, as shown in fig. 4, the water body from the bottom of the condensation tank 83 flows out from the overflow port 13 through the water inlet pipe 41, the filter layer 12 and the tank body 11 to form a low-resistance preferential path, and when more impurities are filtered in the filter layer 12, the resistance of the water flow passing through the filter layer 12 is increased, so that the flow resistance from the bottom of the condensation tank 83 to the overflow port is slowly increased, and when the resistance is increased to exceed the highest point of the condensation tank 83 to the siphon 44, at this time, the highest point of the siphon 44 is fully piled with liquid, when the liquid passes through the siphon 44 and begins to fall at the, therefore, a siphon is established from the bottom of the filter tank 1 to the waste liquid tank 3, the liquid in the filter tank 1 starts to reversely flow and is discharged to the waste liquid tank 3 through the siphon 44, the reversely flowing liquid washes away the impurities accumulated in the filter layer 12, when the impurities mixed into the condensed water on the pipeline of the secondary circulation system 8 and the working machine are not much, but the main heat exchanger 92 is sensitive to the impurities, a thinner filter layer 12 can be selected, so that the reverse flushing can be carried out as long as a little impurities are filtered in the filter layer 12, and the fine impurities are prevented from passing through the filter layer 12. When the water level in the canister 11 drops to the bottom end of the hollow-out pipe 6 inserted into the canister body 11, the gas in the canister 11 reaches the highest point of the siphon tube 44 through the hollow-out pipe 6, and the siphon is broken.

As shown in fig. 3, the condensed water circulation device further includes a cover frame 71, the cover frame 71 wraps the filter tank 1, the liquid storage tank 2, the waste liquid tank 3 and the shunt tube group 4 to form a closed space, a connection pipeline between the liquid storage tank 2 and the secondary circulation pump 85 penetrates through the wall surface of the cover frame 71, a connection pipeline between the shunt tube group 4 and the condensation tank 83 penetrates through the wall surface of the cover frame 71, the cover frame 71 is filled with inert gas, and a vacuum pump or a compressor is arranged on the wall surface of the cover frame 71 to adjust the ambient pressure inside the cover frame 71.

The pressure of the condensed water discharged from the condensing tank 83 is probably not atmospheric pressure according to the parameter requirement of the power generation system, so if the design pressure at the place is higher than atmospheric pressure, the condensed water is directly discharged in an open liquid storage tank 2, so that greater energy is lost, the secondary circulating pump 85 needs to do greater work to pump the condensed water into the main heat exchanger 92, and the condensed water is directly exposed in the air and possibly doped with dissolved oxygen, thereby being not beneficial to the heat exchange of the circulating water in the main heat exchanger 92, and also leading to the oxidation corrosion inside the main heat exchanger 92. If the design pressure there is lower than atmospheric pressure, the flow of condensed water in the filter tank 1 is affected, but instead, atmospheric reflux enters the condensation tank 83 from bottom to top via the shunt tube group 4, which should not happen. Therefore, in order to match the pressure of the condensate discharged from the condensate tank 83 under different design conditions, the filter tank 1, the liquid storage tank 2, the waste liquid tank 3 and the shunt tube group 4 are wrapped by a cover frame 71, and the proper environmental pressure is constructed by a vacuum pump or a compressor on the wall surface, so that the condensate can conveniently flow in and among the tank bodies. The liquid level pressure of the waste liquid tank 3 and the environment pressure of the overflow port 13 also need to be correspondingly matched to meet the siphon condition.

As shown in fig. 3, the water inlet pipe 41 is provided with an electrode 72. The electrode 72 can electrolyze and separate the metal ions and acid ions in the condensed water into metal objects and gas molecules, the metal objects are filtered by the filter layer 12, and the gas molecules are separated out from the water body and are collected to the high point position of the siphon 44. The condensed water passing through the inlet pipe 41 and the filter layer 12 is thus purer.

As shown in fig. 3, the down pipe 43 is provided with the on-off valve 5, the highest point wall surface of the siphon tube 44 is provided with a level sensor 73, and the level sensor 73 is electrically connected to the on-off valve 5.

During the siphon process, it is preferable to disconnect the condensate tank 83 from the tee 42, otherwise, the downcomer 43 will also drain a large amount of water when the siphon occurs until the siphon is disconnected, and this water will also drain to the waste liquid tank 3 through the siphon 44, but this water contains only a small amount of impurities and should not be wasted. Therefore, the invention carries on the break-make through setting up the on-off valve 5 on the downcomer 43, set up the level sensor 73 on the top of the siphon 44, the level sensor 73 detects whether there is water body there, because this position is when there is water body to indicate the siphon process is going on, so give the signal and make the on-off valve 5 close, cut off the downcomer 43 to launch, after the siphon is finished, there is no liquid any more at the highest position of the siphon 44, the on-off valve 5 opens again, the downcomer 43 discharges the condensate water downwards.

As shown in FIG. 3, the downcomer 43 and the descending section of the siphon 44 are provided with a fine mesh wick 49 within the pipe. When the siphon pipe 44 and the downcomer pipe 43 are thick, gas accumulates in the shunt pipe group 4, and during the siphoning process, the gas accumulated at the top of the siphon pipe 44 cannot be exhausted, because the liquid flowing upwards from the tee joint 42 passes through the highest point of the siphon pipe 44 and then flows downwards, the gas cannot be completely extruded downwards on the thick pipe, the gas can disperse into bubbles and float upwards, and is accumulated above the siphon pipe 44, therefore, a fine pore pipe core 49 is arranged in the flow descending section of the downcomer pipe 43 and the siphon pipe 44, the fine pore pipe core 49 is a flow pipe formed by honeycomb-shaped fine pipes, the gas cannot push upwards to open the water body and then float upwards under the fine pipe diameter due to the surface viscous effect of the water, therefore, the gas in the siphon pipe 44 can be exhausted sufficiently during the siphoning process, including gas molecules generated by electrolytic acid radical ions of the electrode 71, it should be noted that the flow of the gas in the rupture pipe 6 should flow in a single direction, that is, it is preferable that the flow of oxygen, carbon dioxide, etc. in the siphon tube 44 is prevented from reaching the inside of the canister 1 through the hollow-out tube 6 only from the canister 1 to the siphon tube 44 without the need for the bidirectional flow,

as shown in fig. 3, the oxygen-absorbing liquid is contained in the waste liquid tank 3, the waste liquid tank 3 includes a discharge pipe 31 extending outward from the bottom or side of the main tank, and the discharge pipe 31 has at least one inlet and one outlet flow direction.

The waste liquid tank 3 wrapped by the cover frame 71 is inconvenient for waste liquid discharge, so that the waste liquid is discharged through a pipeline, the cover frame 71 creates a closed environment, the bottom end of the siphon 44 is sealed by containing oxygen absorption liquid in the waste liquid tank 3, and gas molecules such as the waste liquid and oxygen discharged by the siphon are absorbed by the oxygen absorption liquid, so that the waste liquid and the oxygen are prevented from being diffused into the space in the cover frame 71, and the waste liquid reaches the liquid storage tank 2.

High-temperature steam is introduced from the outside into the water inlet pipe 41. The condensed water discharged from the condensing tank 83 is often in an unsaturated state, in which more gas is dissolved, and after the condensed water is mixed with high-temperature steam, the mixed water is adjusted to be saturated water under local environmental pressure, so that more dissolved gas can be precipitated and collected in the siphon 44, and the subsequent condensed water is purer.

For the continuity of the flow of the water in the secondary circulation system 8, two parts of the components contained in the cover frame 71 are arranged and run in parallel, and the flow rate is adjusted and stabilized by the secondary circulation pump 85.

The operation principle of the device is as follows: condensed water discharged from the condensing tank 83 enters the filter tank 1 through the sewer pipe 43, the tee joint 42 and the water inlet pipe 41, impurities are separated from the filter layer 12, then the impurities overflow from the overflow port 13 and fall into the liquid storage tank 2, and pure condensed water in the liquid storage tank 2 is pumped by the secondary circulating pump 85 to carry out power generation circulation; when more impurities are accumulated on the filter layer 12, the liquid level of the ascending section of the siphon tube 44 continuously ascends until the liquid level exceeds the highest point, after the liquid level exceeds the highest point, siphon is established, the liquid in the filter tank 1 reversely flows through the filter layer 12, and the impurities are washed away, so that the filtering process of the next period is carried out.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. A condensate water circulating apparatus for a nuclear power plant, connecting a secondary circulating pump (85) and a condensate tank (83), characterized in that: the condensed water circulating device comprises a filtering tank (1), a liquid storage tank (2), a waste liquid tank (3) and a shunt pipe group (4), wherein the filtering tank (1) comprises a tank body (11), a filtering layer (12) is arranged at the bottom of the tank body (11), an overflow port (13) is arranged on the side surface of the tank body (11), the outer end of the overflow port (13) is positioned above the liquid storage tank (2), the bottoms of the filtering layer (12), the waste liquid tank (3) and the condensing tank (83) are all connected to the shunt pipe group (4), and the side surface of the bottom of the liquid storage tank (2) is connected to a secondary circulating pump (85);

the flow dividing pipe group (4) comprises a water inlet pipe (41), a tee joint (42), a sewer pipe (43) and a siphon pipe (44), the tee joint (42) is respectively connected with one end of the water inlet pipe (41), the sewer pipe (43) and the siphon pipe (44), the other end of the water inlet pipe (41) is connected to the bottom of the tank body (11), the other end of the sewer pipe (43) is connected to the bottom of the condensation tank (83), the siphon pipe (44) is a section of pipe body which ascends firstly and then descends, the highest point of the siphon pipe (44) is higher than the overflow port (13) and lower than the bottom of the condensation tank (83), the lowest point of the siphon pipe (44) is lower than the bottom of the filter tank (1), a hollow breaking pipe (6) is arranged from the highest point of the siphon pipe (44) to the inside of the tank body (11);

the condensed water circulating device further comprises a cover frame (71), the cover frame (71) wraps the filter tank (1), the liquid storage tank (2), the waste liquid tank (3) and the shunt tube group (4) to form a closed space, a connecting pipeline between the liquid storage tank (2) and the secondary circulating pump (85) penetrates through the wall surface of the cover frame (71), a connecting pipeline between the shunt tube group (4) and the condensing tank (83) penetrates through the wall surface of the cover frame (71), inert gas is filled in the cover frame (71), and a vacuum pump or a compressor is arranged on the wall surface of the cover frame (71) to adjust the environment pressure in the cover frame (71);

an electrode (72) is arranged on the water inlet pipe (41), and a pore pipe core (49) is arranged in the descending section of the downcomer (43) and the siphon (44).