CA2268520C - Method and device for obtaining a liquid sample - Google Patents
Method and device for obtaining a liquid sample Download PDFInfo
- Publication number
- CA2268520C CA2268520C CA002268520A CA2268520A CA2268520C CA 2268520 C CA2268520 C CA 2268520C CA 002268520 A CA002268520 A CA 002268520A CA 2268520 A CA2268520 A CA 2268520A CA 2268520 C CA2268520 C CA 2268520C
- Authority
- CA
- Canada
- Prior art keywords
- sampling vessel
- pressure pulse
- container
- liquid
- reactor containment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/10—Devices for withdrawing samples in the liquid or fluent state
- G01N1/14—Suction devices, e.g. pumps; Ejector devices
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21C—NUCLEAR REACTORS
- G21C17/00—Monitoring; Testing ; Maintaining
- G21C17/02—Devices or arrangements for monitoring coolant or moderator
- G21C17/022—Devices or arrangements for monitoring coolant or moderator for monitoring liquid coolants or moderators
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/10—Devices for withdrawing samples in the liquid or fluent state
- G01N2001/1031—Sampling from special places
- G01N2001/1037—Sampling from special places from an enclosure (hazardous waste, radioactive)
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- General Engineering & Computer Science (AREA)
- High Energy & Nuclear Physics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Sampling And Sample Adjustment (AREA)
- Monitoring And Testing Of Nuclear Reactors (AREA)
- Automatic Analysis And Handling Materials Therefor (AREA)
Abstract
A gas cushion (15) is formed in a gas cushion space (13) of a sampling vessel (8) with the aid of a pressure pulse (28). The gas cushion (15) is utilized for conveying at least some of the liquid (6) located in the sampling vessel (8) out of the reactor containment (2).
Description
FILE,~-~'T!9' t Description Method and device for obtaining a liquid sample The invention relates to a method and a device for obtaining a liquid sample from the reactor contain-ment of a nuclear power station by means of a sampling vessel.
In the nuclear sector, there is often the job of obtaining representative liquid samples of the liquid present in the containment from outside, without a strength and leak tightness of the containment being impaired. These samples undergo measurements, for example for radioactivity, outside the containment. During sampling, deposits of sampled constituents, the said deposits falsifying the measurement result, should be avoided. Moreover, it should be possible to carry out the collection of samples by means of preferably mechanically passive components which can also be designed for inci-dent conditions.
In the collection of liquid samples from the interior of the reactor containment of a nuclear power station, in particular from its sump, the conditions which prevail are made more difficult by a serious incident or accident. It may be highly disadvantageous to suck up the sump medium on account of the possibly high vapour pressure of this sump medium. And, for example for reasons of availability of electrical energy, because of insufficient radiation resistance, etc., the operation of a pump may not be adequately ensured. It is therefore necessary, here, to look for ways of guaranteeing reli-able sampling, even under these difficult conditions.
EP 0,598,789 el discloses a method and a device for obtaining samples from the atmosphere in a contain-ment closed off in a gas-tight manner, in particular from the reactor containment of a nuclear power station. In this case, the sample is introduced into a sampling vessel, and constituents of the sample which can be dissolved and/or condensed in a transport fluid are discharged, together with the transport fluid, from the reactor containment. It should be noted that the method described there and the associated device are not designed for liquid samples, but for gaseous samples.
An object of embodiments of the present invention is, therefore, to specify a method and a device of the type mentioned in the introduction which are designed for the collection of liquid samples and work safely even under the difficult conditions mentioned.
Accordingly, in one aspect of the invention, there is provided a method for obtaining a liquid sample from the reactor containment of a nuclear power station by means of a sampling vessel, the method comprising: forming a gas cushion in the sampling vessel with the aid of a pressure pulse; and utilizing the gas cushion for conveying at least some of the liquid located in the sampling vessel out of the reactor containment.
In another aspect of the invention, there is provided a device for obtaining a liquid sample from the reactor containment of a nuclear power station the device comprising: a sampling vessel for forming a gas cushion therein, the sampling vessel comprising an upper part and a gas cushion space and the gas cushion being for conveying at least some of the liquid located in the sampling vessel out of the reactor containment; and a pressure pulse generator connected to the sampling vessel, the pressure pulse generator being for generating a pressure pulse to aid in forming the gas cushion.
- 2a -Preferably, the procedure is such that, in a preceding first phase prior to the application of the pressure pulse, liquid is introduced into the sampling vessel from the reactor containment. This may be carried out, in particular, by connecting a container, put under a vacuum, to the sampling vessel. The container then sucks liquid out of the reactor containment into the sampling vessel via the cut-in connecting conduit.
In the subsequent second phase, the gas cushion is formed, as mentioned, in the sampling vessel with the aid of the pressure pulse. This may be carried out by opening a reservoir which is under pressure. For example, this reservoir may be a container brought to pressure by a compressor or else a gas bottle which is under characteristic pressure.
The parameters of the pressure pulse are governed by local circumstances. For conventional designs, the magnitude of the pressure pulse may be a few bar, prefer-ably 2 to 5 bar, and the duration of the pressure pulse may be a few seconds, preferably 20 to 100 seconds.
In a third phase which is subsequent to this and which follows the application of the pressure pulse, the gas cushion in the sampling vessel may be expanded into a container which is under a vacuum. At least some of the liquid located in the sampling vessel is thereby forced out of the sampling vessel into the container.
The said object as regards the device is achieved, according to the invention, in that the sampl-ing vessel has, in the upper part, a gas cushion space which is connected to a pressure pulse generator.
A preferred embodiment is distinguished in that the sampling vessel is a preferably cylindrical vessel with a liquid inlet orifice in the bottom region and with a gas passage orifice in the top region as well as with a bypass conduit between the bottom region and a connec-tion located outside the top region.
A reservoir to be opened by means of a valve, for example a container which can be brought to pressure by a compressor or else a gas bottle, may be provided as a pressure pulse generator.
The pressure pulse generator will expediently be connected to a gas passage orifice in the top region of the sampling vessel via a conduit leading into the reactor containment.
Furthermore, a container which can be brought to a vacuum may be connected to the sampling vessel via a connecting fitting. The two last-mentioned embodiments may advant-ageously be combined with one another, in such a way that only a single lead-through is required in the reactor containment.
Furthermore, a liquid pump and a gas compressor may be connected to the outlets of the container.
Exemplary embodiments of the invention are explained in more detail below with reference to seven Figures of which:
Figure 1 shows a device for obtaining a liquid sample, the said device working by means of the pressure pulse technique according to the invention, Figure 2 shows a detail of this device in the first phase, in which the sampling vessel is filled, Figure 3 shows the same detail in the second phase, in which a conveying pressure is exerted in the sampling vessel by means of a pressure pulse, Figure 4 shows the same detail, in which, in the third phase, the relief of pressure and a conveyance of sump water take place, Figure 5 shows a basic diagram of the inlet orifice of the sampling vessel, the said inlet orifice here having a discontinuous outlet and a continuous inlet, Figure 6 shows a basic diagram of the sampling vessel with a preceding cylindrical chamber in the suction phase (low resistance), Figure 7 shows the basic diagram, shown in Figure 6, in the conveying phase (high resistance).
The device according to Figure 1 is designed for the reactor containment 2 of a nuclear power station which is not illustrated in any more detail. Located within this reactor containment 2 is a sump 4 comprising a liquid sump medium 6, especially water, which, in the event of an incident, may be mixed with radioactivity and which is to be monitored in this regard. For this pur-pose, a sampling vessel 8 is arranged in the sump 4. In the present case, this sampling vessel is designed to be esseihtially cylindrical at the top and then.to be conical at the bottom. It possesses in the bottom region a liquid inlet orifice 10 and in the top region a gas passage orifice 12, the latter being provided with a connection for a conveying conduit 14. A bypass conduit 16 is arranged between the bottom region or somewhat above this, as illustrated, and a connection point 14a is located outside the top region. A gas cushion space 13 is formed in the upper part of the sampling vessel 8 and, in a particular operating phase, is filled with a gas cushion 15 (preferably composed of air). The conveying conduit 14 is connected to a branch point 20 via a lead-through 17, passing through the wall of the reactor containment 2, and two shut-off fittings 18.
Connected to the branch point 20 are, on the one hand, a pressure pulse generator 22 and, on the other hand, a container 24 which performs various functions.
On one side, the pressure pulse generator 22 is connected via a pressure pulse conduit 26, via which pressure pulses can be transmitted in the direction of the reactor containment 2 at appropriate times. Such a pressure pulse is designated diagraamnatically on the pressure pulse conduit 26 by 28. In the present case, the pressure pulse generator 22 consists of a reservoir 30 which is connected to the conduit 26 via a valve 32. The reservoir 30 may be a container 34 which is brought to or maintained at overpressure by means of a compressor 36.
in this case, air or nitrogen may serve for generating pressure. it is also possible for an appropriate gas bottle or a plurality of such bottles to be used as a reservoir 30. It is important that the valve 32 be a valve with a quick switching action.
The container 24 is located on the other side of the branch point 20 via a connecting conduit 40 and a connecting fitting 42. As becomes clear later, the container 24 acts not only as a collecting or receiving vessel for the liquid sample, but also as a vacuum generator. The container 24 is connected to an analyser 46 by means of a first outlet via a liquid pump 44. This analyser 46 serves for sample dilution and analysis. In particular, it measures the radioactivity present in the sample. Its outlet is connected to the connecting conduit 40 and consequently to the branch point 20 via a return conduit 48 and a valve 50.
A second outlet of the container 24 likewise leads to the connecting conduit 40 and consequently to the branch point 20 via an evacuating conduit 52 and a compressor 54 and via a valve 56. it can thus be seen that both the pressure pulse generator 22, with the aid of the valve 32, and the container 24, with the aid of the connecting fitting 42, can be connected to the conveying conduit 14 and can consequently be connected to the sampling vessel 8.
The following statement can be made as regards the functioning of the device illustrated:
In a preliminary phase, first the sampling vessel 8, submerged or dipped in the sump 4 of the reactor containment 2, is subjected to pressure. This is carried out by means of compressed air or nitrogen from the pressure pulse generator 22 via the conveying conduit 14, the fittings 18 and the valve 32. The sampling vessel 8 is thereby emptied.
In the first phase which then follows, which is illustrated particularly in Figure 2, the filling of the sampling vessel 8 takes place. This sampling vessel 8 is brought to a pressure lower than that of the reactor containment 2 by opening the connecting fitting 42 to the container 24 which has a lower pressure than in the reactor containment 2. The sampling vessel 8 is thereby filled with sump medium 6.
The application of the conveying pressure is subsequently carried out in a second phase. For this purpose, the sampling vessel 8 is briefly subjected to gas pressure from the container 34 via the quick-opening valve 32. A pressure pulse 28 is thus discharged by the pressure pulse generator 22. Due to the gas pressure, the liquid in the sampling vessel 8 escapes through the inlet orifice 10 located at the bottom. A backwash into the reactor containment 2 therefore takes place.
In the subsequent third phase, the relief of pressure and consequently the conveyance of sump water are brought about. In this phase, the gas located in the conduits 14, 26 and 40 is expanded rapidly into the container 24 which, at this moment, has a pressure which is lower than that of the reactor containment 2. As a result, via the conveying conduit 14, specifically because of the gas cushion 15 in the gas cushion space 13 of the sampling vessel 8, some of the liquid located in the sampling vessel 8 is con-veyed out of the reactor containment 2 via the conveying conduit 14. This portion of liquid passes as a sample into the container 24. It may undergo measurement in the analyser 46.
To prepare for further sampling, the container 24 is subsequently evacuated by means of the compressor 54.
By means of the device illustrated in Figure 1, it is possible to sample lower-lying and/or boiling liquids by means of only one conduit 14 which penetrates the reactor containment 2 in the lead-through 17. Convey-ance via high points in the conduits 14, 26, 40, evapo-ration being avoided, is possible, the said high points being easy to implement in the plant.
It is also important that the inflow of the sample into the sampling vessel 8 take place from below.
Sediments can thereby be flushed out in each case, and the next sample is not contaminated.
The conveying conduit diameter is selected as smaller than/equal to DN 10, so that, due to the prevail-ing surface tension, a water plug flow is achieved, and segregation in horizontal conduit parts into a two-phase flow is avoided.
In advantageous embodiments of the inlet orifice 10 of the sampling vessel 8 for reducing the liquid quantity washed backed into the reactor containment 2, this inlet orifice 10 is designed in such a way that the pressure losses in the two directions of flow (during the filling of the vessel 8 and during the backwash into the reactor containment 2) are different.
Figure 5 shows, in this case, an embodiment with a nipple 58. This nipple 58 is located at the lower end of the sampling vessel 8. It possesses an inlet orifice 62 which is continuous in the inlet direction 60 and an inlet orifice 66 which is discontinuous in the outlet direction 64. The nipple 58 thus acts as a one-sided flow limiter. Here, the coefficient of pressure loss of the inlet orifice 62 is lower by the factor 2 to 3 in the inlet direction 60 than in the outlet direction 64.
It is particularly advantageous to equip a sampling vessel 8 with a one-sided flow limiter 70, as shown in Figures 6 and 7. The latter has low resistance in the suction phase (Figure 6) and high resistance in the conveying phase (Figure 7). The flow limiter 70 comprises a cylindrical chamber 72 with a tangential connection piece 74 and with an axial connection piece 76.
In the suction phase (see Figure 6), that is to say during the filling of the sampling vessel 8, the sump medium 6 flows in through the axial connection piece 76, floods the cylindrical chamber 72 and overflows from this into the sampling vessel 8 via the tangential connection piece 74. The flow resistance of the flow limiter 70 is low in this direction. It may be maintained even lower, for example, by means of diffusers in the two connection pieces 74, 76.
In the subsequent conveying phase (see Figure 7), a vortex with a correspondingly high pressure loss is formed in the cylindrical chamber 72 and in the outlet connection piece 76 due to tangential entry via the connection piece 74. The literature discloses, in the case of comparable flow forms, for example in the separation of dust from gases in cyclones, pressure losses which amount to a multiple of, for example more than fifty times, the pressure loss of a pipe bend through which a flow passes corres-pondingly.
The flow limiter 70 is preferably installed in such a way that, when pressure is first applied, emptying of residues is made possible, that is to say the axial connection piece 76 is installed in the vertical direc-tion.
The advantage of equipping the sampling vessel 8 with the flow limiter 70 according to Figures 6 and 7 is that, with the cross-section of the inlet orifice being unchanged, the duration of the conveying phase may be lengthened appreciably and therefore the total conveyed quantity of sump medium and the delivery head obtainable are also increased.
In the nuclear sector, there is often the job of obtaining representative liquid samples of the liquid present in the containment from outside, without a strength and leak tightness of the containment being impaired. These samples undergo measurements, for example for radioactivity, outside the containment. During sampling, deposits of sampled constituents, the said deposits falsifying the measurement result, should be avoided. Moreover, it should be possible to carry out the collection of samples by means of preferably mechanically passive components which can also be designed for inci-dent conditions.
In the collection of liquid samples from the interior of the reactor containment of a nuclear power station, in particular from its sump, the conditions which prevail are made more difficult by a serious incident or accident. It may be highly disadvantageous to suck up the sump medium on account of the possibly high vapour pressure of this sump medium. And, for example for reasons of availability of electrical energy, because of insufficient radiation resistance, etc., the operation of a pump may not be adequately ensured. It is therefore necessary, here, to look for ways of guaranteeing reli-able sampling, even under these difficult conditions.
EP 0,598,789 el discloses a method and a device for obtaining samples from the atmosphere in a contain-ment closed off in a gas-tight manner, in particular from the reactor containment of a nuclear power station. In this case, the sample is introduced into a sampling vessel, and constituents of the sample which can be dissolved and/or condensed in a transport fluid are discharged, together with the transport fluid, from the reactor containment. It should be noted that the method described there and the associated device are not designed for liquid samples, but for gaseous samples.
An object of embodiments of the present invention is, therefore, to specify a method and a device of the type mentioned in the introduction which are designed for the collection of liquid samples and work safely even under the difficult conditions mentioned.
Accordingly, in one aspect of the invention, there is provided a method for obtaining a liquid sample from the reactor containment of a nuclear power station by means of a sampling vessel, the method comprising: forming a gas cushion in the sampling vessel with the aid of a pressure pulse; and utilizing the gas cushion for conveying at least some of the liquid located in the sampling vessel out of the reactor containment.
In another aspect of the invention, there is provided a device for obtaining a liquid sample from the reactor containment of a nuclear power station the device comprising: a sampling vessel for forming a gas cushion therein, the sampling vessel comprising an upper part and a gas cushion space and the gas cushion being for conveying at least some of the liquid located in the sampling vessel out of the reactor containment; and a pressure pulse generator connected to the sampling vessel, the pressure pulse generator being for generating a pressure pulse to aid in forming the gas cushion.
- 2a -Preferably, the procedure is such that, in a preceding first phase prior to the application of the pressure pulse, liquid is introduced into the sampling vessel from the reactor containment. This may be carried out, in particular, by connecting a container, put under a vacuum, to the sampling vessel. The container then sucks liquid out of the reactor containment into the sampling vessel via the cut-in connecting conduit.
In the subsequent second phase, the gas cushion is formed, as mentioned, in the sampling vessel with the aid of the pressure pulse. This may be carried out by opening a reservoir which is under pressure. For example, this reservoir may be a container brought to pressure by a compressor or else a gas bottle which is under characteristic pressure.
The parameters of the pressure pulse are governed by local circumstances. For conventional designs, the magnitude of the pressure pulse may be a few bar, prefer-ably 2 to 5 bar, and the duration of the pressure pulse may be a few seconds, preferably 20 to 100 seconds.
In a third phase which is subsequent to this and which follows the application of the pressure pulse, the gas cushion in the sampling vessel may be expanded into a container which is under a vacuum. At least some of the liquid located in the sampling vessel is thereby forced out of the sampling vessel into the container.
The said object as regards the device is achieved, according to the invention, in that the sampl-ing vessel has, in the upper part, a gas cushion space which is connected to a pressure pulse generator.
A preferred embodiment is distinguished in that the sampling vessel is a preferably cylindrical vessel with a liquid inlet orifice in the bottom region and with a gas passage orifice in the top region as well as with a bypass conduit between the bottom region and a connec-tion located outside the top region.
A reservoir to be opened by means of a valve, for example a container which can be brought to pressure by a compressor or else a gas bottle, may be provided as a pressure pulse generator.
The pressure pulse generator will expediently be connected to a gas passage orifice in the top region of the sampling vessel via a conduit leading into the reactor containment.
Furthermore, a container which can be brought to a vacuum may be connected to the sampling vessel via a connecting fitting. The two last-mentioned embodiments may advant-ageously be combined with one another, in such a way that only a single lead-through is required in the reactor containment.
Furthermore, a liquid pump and a gas compressor may be connected to the outlets of the container.
Exemplary embodiments of the invention are explained in more detail below with reference to seven Figures of which:
Figure 1 shows a device for obtaining a liquid sample, the said device working by means of the pressure pulse technique according to the invention, Figure 2 shows a detail of this device in the first phase, in which the sampling vessel is filled, Figure 3 shows the same detail in the second phase, in which a conveying pressure is exerted in the sampling vessel by means of a pressure pulse, Figure 4 shows the same detail, in which, in the third phase, the relief of pressure and a conveyance of sump water take place, Figure 5 shows a basic diagram of the inlet orifice of the sampling vessel, the said inlet orifice here having a discontinuous outlet and a continuous inlet, Figure 6 shows a basic diagram of the sampling vessel with a preceding cylindrical chamber in the suction phase (low resistance), Figure 7 shows the basic diagram, shown in Figure 6, in the conveying phase (high resistance).
The device according to Figure 1 is designed for the reactor containment 2 of a nuclear power station which is not illustrated in any more detail. Located within this reactor containment 2 is a sump 4 comprising a liquid sump medium 6, especially water, which, in the event of an incident, may be mixed with radioactivity and which is to be monitored in this regard. For this pur-pose, a sampling vessel 8 is arranged in the sump 4. In the present case, this sampling vessel is designed to be esseihtially cylindrical at the top and then.to be conical at the bottom. It possesses in the bottom region a liquid inlet orifice 10 and in the top region a gas passage orifice 12, the latter being provided with a connection for a conveying conduit 14. A bypass conduit 16 is arranged between the bottom region or somewhat above this, as illustrated, and a connection point 14a is located outside the top region. A gas cushion space 13 is formed in the upper part of the sampling vessel 8 and, in a particular operating phase, is filled with a gas cushion 15 (preferably composed of air). The conveying conduit 14 is connected to a branch point 20 via a lead-through 17, passing through the wall of the reactor containment 2, and two shut-off fittings 18.
Connected to the branch point 20 are, on the one hand, a pressure pulse generator 22 and, on the other hand, a container 24 which performs various functions.
On one side, the pressure pulse generator 22 is connected via a pressure pulse conduit 26, via which pressure pulses can be transmitted in the direction of the reactor containment 2 at appropriate times. Such a pressure pulse is designated diagraamnatically on the pressure pulse conduit 26 by 28. In the present case, the pressure pulse generator 22 consists of a reservoir 30 which is connected to the conduit 26 via a valve 32. The reservoir 30 may be a container 34 which is brought to or maintained at overpressure by means of a compressor 36.
in this case, air or nitrogen may serve for generating pressure. it is also possible for an appropriate gas bottle or a plurality of such bottles to be used as a reservoir 30. It is important that the valve 32 be a valve with a quick switching action.
The container 24 is located on the other side of the branch point 20 via a connecting conduit 40 and a connecting fitting 42. As becomes clear later, the container 24 acts not only as a collecting or receiving vessel for the liquid sample, but also as a vacuum generator. The container 24 is connected to an analyser 46 by means of a first outlet via a liquid pump 44. This analyser 46 serves for sample dilution and analysis. In particular, it measures the radioactivity present in the sample. Its outlet is connected to the connecting conduit 40 and consequently to the branch point 20 via a return conduit 48 and a valve 50.
A second outlet of the container 24 likewise leads to the connecting conduit 40 and consequently to the branch point 20 via an evacuating conduit 52 and a compressor 54 and via a valve 56. it can thus be seen that both the pressure pulse generator 22, with the aid of the valve 32, and the container 24, with the aid of the connecting fitting 42, can be connected to the conveying conduit 14 and can consequently be connected to the sampling vessel 8.
The following statement can be made as regards the functioning of the device illustrated:
In a preliminary phase, first the sampling vessel 8, submerged or dipped in the sump 4 of the reactor containment 2, is subjected to pressure. This is carried out by means of compressed air or nitrogen from the pressure pulse generator 22 via the conveying conduit 14, the fittings 18 and the valve 32. The sampling vessel 8 is thereby emptied.
In the first phase which then follows, which is illustrated particularly in Figure 2, the filling of the sampling vessel 8 takes place. This sampling vessel 8 is brought to a pressure lower than that of the reactor containment 2 by opening the connecting fitting 42 to the container 24 which has a lower pressure than in the reactor containment 2. The sampling vessel 8 is thereby filled with sump medium 6.
The application of the conveying pressure is subsequently carried out in a second phase. For this purpose, the sampling vessel 8 is briefly subjected to gas pressure from the container 34 via the quick-opening valve 32. A pressure pulse 28 is thus discharged by the pressure pulse generator 22. Due to the gas pressure, the liquid in the sampling vessel 8 escapes through the inlet orifice 10 located at the bottom. A backwash into the reactor containment 2 therefore takes place.
In the subsequent third phase, the relief of pressure and consequently the conveyance of sump water are brought about. In this phase, the gas located in the conduits 14, 26 and 40 is expanded rapidly into the container 24 which, at this moment, has a pressure which is lower than that of the reactor containment 2. As a result, via the conveying conduit 14, specifically because of the gas cushion 15 in the gas cushion space 13 of the sampling vessel 8, some of the liquid located in the sampling vessel 8 is con-veyed out of the reactor containment 2 via the conveying conduit 14. This portion of liquid passes as a sample into the container 24. It may undergo measurement in the analyser 46.
To prepare for further sampling, the container 24 is subsequently evacuated by means of the compressor 54.
By means of the device illustrated in Figure 1, it is possible to sample lower-lying and/or boiling liquids by means of only one conduit 14 which penetrates the reactor containment 2 in the lead-through 17. Convey-ance via high points in the conduits 14, 26, 40, evapo-ration being avoided, is possible, the said high points being easy to implement in the plant.
It is also important that the inflow of the sample into the sampling vessel 8 take place from below.
Sediments can thereby be flushed out in each case, and the next sample is not contaminated.
The conveying conduit diameter is selected as smaller than/equal to DN 10, so that, due to the prevail-ing surface tension, a water plug flow is achieved, and segregation in horizontal conduit parts into a two-phase flow is avoided.
In advantageous embodiments of the inlet orifice 10 of the sampling vessel 8 for reducing the liquid quantity washed backed into the reactor containment 2, this inlet orifice 10 is designed in such a way that the pressure losses in the two directions of flow (during the filling of the vessel 8 and during the backwash into the reactor containment 2) are different.
Figure 5 shows, in this case, an embodiment with a nipple 58. This nipple 58 is located at the lower end of the sampling vessel 8. It possesses an inlet orifice 62 which is continuous in the inlet direction 60 and an inlet orifice 66 which is discontinuous in the outlet direction 64. The nipple 58 thus acts as a one-sided flow limiter. Here, the coefficient of pressure loss of the inlet orifice 62 is lower by the factor 2 to 3 in the inlet direction 60 than in the outlet direction 64.
It is particularly advantageous to equip a sampling vessel 8 with a one-sided flow limiter 70, as shown in Figures 6 and 7. The latter has low resistance in the suction phase (Figure 6) and high resistance in the conveying phase (Figure 7). The flow limiter 70 comprises a cylindrical chamber 72 with a tangential connection piece 74 and with an axial connection piece 76.
In the suction phase (see Figure 6), that is to say during the filling of the sampling vessel 8, the sump medium 6 flows in through the axial connection piece 76, floods the cylindrical chamber 72 and overflows from this into the sampling vessel 8 via the tangential connection piece 74. The flow resistance of the flow limiter 70 is low in this direction. It may be maintained even lower, for example, by means of diffusers in the two connection pieces 74, 76.
In the subsequent conveying phase (see Figure 7), a vortex with a correspondingly high pressure loss is formed in the cylindrical chamber 72 and in the outlet connection piece 76 due to tangential entry via the connection piece 74. The literature discloses, in the case of comparable flow forms, for example in the separation of dust from gases in cyclones, pressure losses which amount to a multiple of, for example more than fifty times, the pressure loss of a pipe bend through which a flow passes corres-pondingly.
The flow limiter 70 is preferably installed in such a way that, when pressure is first applied, emptying of residues is made possible, that is to say the axial connection piece 76 is installed in the vertical direc-tion.
The advantage of equipping the sampling vessel 8 with the flow limiter 70 according to Figures 6 and 7 is that, with the cross-section of the inlet orifice being unchanged, the duration of the conveying phase may be lengthened appreciably and therefore the total conveyed quantity of sump medium and the delivery head obtainable are also increased.
Claims (18)
1. A method for obtaining a liquid sample from the reactor containment of a nuclear power station by means of a sampling vessel, the method comprising:
forming a gas cushion in the sampling vessel with the aid of a pressure pulse;
and utilizing the gas cushion for conveying at least some of the liquid located in the sampling vessel out of the reactor containment.
forming a gas cushion in the sampling vessel with the aid of a pressure pulse;
and utilizing the gas cushion for conveying at least some of the liquid located in the sampling vessel out of the reactor containment.
2. The method according to claim 1, further comprising, before the pressure pulse is applied, introducing liquid into the sampling vessel from the reactor containment.
3. The method according to claim 2, wherein the liquid is introduced into a container which is under a vacuum is connected to the sampling vessel.
4. The method according to any one of claims 1 to 3, wherein the pressure pulse is generated by opening a reservoir which is under pressure.
5. The method of claim 4, wherein the reservoir comprises a container, brought to pressure by a compressor, or a gas bottle.
6. Method according to any one of claims 1 to 5, wherein the magnitude of the pressure pulse is 2 to 5 bar, and the duration of the pressure pulse is 20 to 100 seconds.
7. The method according to any one of claims 1 or 2, wherein, after the pressure pulse has been applied, the gas cushion in the sampling vessel is expanded into a container which is under a vacuum, with the result that at least some of the liquid located in the sampling vessel is forced out of the sampling vessel into this container.
8. A device for obtaining a liquid sample from the reactor containment of a nuclear power station, the device comprising:
a sampling vessel for forming a gas cushion therein, the sampling vessel comprising an upper part and a gas cushion space and the gas cushion being for conveying at least some of the liquid located in the sampling vessel out of the reactor containment; and a pressure pulse generator connected to the sampling vessel, the pressure pulse generator being for generating a pressure pulse to aid in forming the gas cushion.
a sampling vessel for forming a gas cushion therein, the sampling vessel comprising an upper part and a gas cushion space and the gas cushion being for conveying at least some of the liquid located in the sampling vessel out of the reactor containment; and a pressure pulse generator connected to the sampling vessel, the pressure pulse generator being for generating a pressure pulse to aid in forming the gas cushion.
9. The device according to claim 8, wherein the sampling vessel is a cylindrical vessel with a liquid inlet orifice in a bottom region and with a gas passage orifice in a top region as well as with a bypass conduit between the bottom region and a connection point located outside the top region.
10. The device according to claim 8 or 9, wherein the pressure pulse generator comprises a reservoir to be opened by means of a valve.
11. The device according to claim 10, wherein the reservoir comprises a container, which can be brought to pressure by a compressor, or a gas bottle.
12. The device according to any one of claims 8 to 11, wherein the pressure pulse generator is connected to a gas passage orifice in the upper part of the sampling vessel via a conduit leading into the reactor containment.
13. The device according to any one of claims 8 to 12, wherein a container which can be brought to a vacuum is connected to the sampling vessel via a connecting fitting.
14. The device according to claim 13, wherein an analyser for liquids is connected to the outlet of the container.
15. The device according to claim 13 or 14, wherein a liquid pump and a gas compressor are connected to outlets of the container.
16. The device according to any one of claims 8 to 15, wherein a conveying conduit is connected to a gas passage orifice in the upper part of the sampling vessel, the said conveying conduit leading to a branch point, at which a pressure pulse conduit and a connecting conduit are connected.
17. The device according to any one of claims 8 to 16, wherein the liquid inlet orifice is formed by a nipple with a continuous inlet and a discontinuous outlet.
18. The device according to any one of claims 8 to 16, wherein the liquid inlet orifice is formed by a hollow cylindrical chamber with a tangential connection piece and an axial connection piece.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19642382A DE19642382C2 (en) | 1996-10-14 | 1996-10-14 | Method and device for obtaining a liquid sample |
| DE19642382.1 | 1996-10-14 | ||
| PCT/DE1997/002269 WO1998016934A1 (en) | 1996-10-14 | 1997-10-02 | Method and device for obtaining a fluid sample |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2268520A1 CA2268520A1 (en) | 1998-04-23 |
| CA2268520C true CA2268520C (en) | 2007-05-29 |
Family
ID=7808733
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002268520A Expired - Fee Related CA2268520C (en) | 1996-10-14 | 1997-10-02 | Method and device for obtaining a liquid sample |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0931317B1 (en) |
| JP (1) | JP3486664B2 (en) |
| KR (1) | KR100547403B1 (en) |
| CN (1) | CN1123012C (en) |
| CA (1) | CA2268520C (en) |
| DE (2) | DE19642382C2 (en) |
| ES (1) | ES2168619T3 (en) |
| RU (1) | RU2179756C2 (en) |
| TW (1) | TW362216B (en) |
| UA (1) | UA44362C2 (en) |
| WO (1) | WO1998016934A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101782478B (en) * | 2010-03-09 | 2011-11-02 | 中国原子能科学研究院 | Hot chamber sampling device |
| DE102015221151B3 (en) | 2015-10-29 | 2016-10-27 | Areva Gmbh | Sampling vessel and sampling system and related operating procedures |
| KR102475791B1 (en) * | 2021-12-09 | 2022-12-08 | 삼진공작 (주) | Sampling and sample analysis system in vacuum region and low pressure region of water heaters |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2921351C2 (en) * | 1979-05-25 | 1984-03-08 | Kraftwerk Union AG, 4330 Mülheim | Method and device for taking a sample from the filter bed of a synthetic resin filter |
| DE3129822A1 (en) * | 1981-07-29 | 1983-02-17 | Dornier System Gmbh, 7990 Friedrichshafen | Device for monitoring the concentration of radioactive nuclides, particularly of alpha -ray emitters, in a gas or a liquid |
| US4674343A (en) * | 1984-09-07 | 1987-06-23 | The United States Of America As Represented By The United States Department Of Energy | Liquid sampling system |
| US4882122A (en) * | 1988-02-10 | 1989-11-21 | General Electric Company | Method and apparatus for obtaining a water sample from the core of a boiling water reactor |
| FI904517A0 (en) * | 1989-09-29 | 1990-09-13 | Siemens Ag | FOERFARANDE FOER OEVERVAKNING AV AKTIVITETEN HOS EN GASFORMIG ELLER VAETSKEFORMIG MELLANPRODUKT I ETT OEVERVAKNINGSOMRAODE AV EN KAERNTEKNISK ANLAEGGNING SAMT ANORDNING FOER UTFOERANDE AV FOERFARANDET. |
| DE4023841A1 (en) * | 1990-07-27 | 1992-02-06 | Wiederaufarbeitung Von Kernbre | DEVICE FOR TAKING GAS AND / OR LIQUID SAMPLES FROM A SECURITY CONTAINER FROM NUCLEAR POWER PLANTS |
| DE4126894A1 (en) * | 1991-08-14 | 1993-02-18 | Siemens Ag | METHOD AND DEVICE FOR OBTAINING SAMPLES FROM THE ATMOSPHERIC CONTAINER CONTAINED IN A GAS-TIGHT, IN PARTICULAR FROM THE REACTOR SAFETY CONTAINER OF A NUCLEAR POWER PLANT |
| US5367546A (en) * | 1993-06-23 | 1994-11-22 | Westinghouse Electric Corporation | Fluid sampling system for a nuclear reactor |
-
1996
- 1996-10-14 DE DE19642382A patent/DE19642382C2/en not_active Expired - Fee Related
-
1997
- 1997-02-10 UA UA99042112A patent/UA44362C2/en unknown
- 1997-09-18 TW TW086113502A patent/TW362216B/en not_active IP Right Cessation
- 1997-10-02 KR KR1019997003230A patent/KR100547403B1/en not_active IP Right Cessation
- 1997-10-02 CN CN97197877A patent/CN1123012C/en not_active Expired - Lifetime
- 1997-10-02 RU RU99110371/06A patent/RU2179756C2/en active
- 1997-10-02 DE DE59705803T patent/DE59705803D1/en not_active Expired - Lifetime
- 1997-10-02 EP EP97912038A patent/EP0931317B1/en not_active Expired - Lifetime
- 1997-10-02 JP JP51788998A patent/JP3486664B2/en not_active Expired - Fee Related
- 1997-10-02 ES ES97912038T patent/ES2168619T3/en not_active Expired - Lifetime
- 1997-10-02 WO PCT/DE1997/002269 patent/WO1998016934A1/en active IP Right Grant
- 1997-10-02 CA CA002268520A patent/CA2268520C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| DE19642382C2 (en) | 2001-12-06 |
| CA2268520A1 (en) | 1998-04-23 |
| JP3486664B2 (en) | 2004-01-13 |
| DE19642382A1 (en) | 1998-04-16 |
| ES2168619T3 (en) | 2002-06-16 |
| CN1123012C (en) | 2003-10-01 |
| EP0931317A1 (en) | 1999-07-28 |
| TW362216B (en) | 1999-06-21 |
| JP2001502059A (en) | 2001-02-13 |
| CN1230281A (en) | 1999-09-29 |
| KR100547403B1 (en) | 2006-01-31 |
| DE59705803D1 (en) | 2002-01-24 |
| WO1998016934A1 (en) | 1998-04-23 |
| RU2179756C2 (en) | 2002-02-20 |
| EP0931317B1 (en) | 2001-12-12 |
| UA44362C2 (en) | 2002-02-15 |
| KR20000049141A (en) | 2000-07-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6766161B2 (en) | Sampling container and sampling system and corresponding operating method | |
| US4764344A (en) | Device for the determination of the quantitative composition of gases | |
| EP1918631B1 (en) | Leak containment system for reactive gases | |
| EP0356877B1 (en) | Process for controlling the tightness of a test container using a tracer gas | |
| JP3195347B2 (en) | Method and apparatus for extracting a sample from the atmosphere in a hermetically sealed container | |
| CA2268520C (en) | Method and device for obtaining a liquid sample | |
| US5367546A (en) | Fluid sampling system for a nuclear reactor | |
| RU94015263A (en) | METHOD AND DEVICE FOR OBTAINING SAMPLES FROM THE ATMOSPHERE IN A SEALED CLOSED TANK, IN PARTICULAR FROM THE TANK OF EMERGENCY PROTECTION OF A NUCLEAR ELECTRIC POWER REACTOR | |
| US5116330A (en) | Sample extraction system | |
| WO1989005514A1 (en) | Counterflow leak detector with high and low sensitivity operating modes | |
| CN211507142U (en) | Radioactive waste resin negative pressure conveying device | |
| EP0155107B1 (en) | A sampling system | |
| RU2419776C2 (en) | Automatic system of liquid sample analytical control | |
| CN117073920A (en) | Pressurized helium leak detection method | |
| US11090625B2 (en) | Apparatus and method for withdrawing samples from a unit of a polymerization plant | |
| FR3109012A1 (en) | STEAM GENERATOR ACCIDENT MITIGATION SYSTEM | |
| JP3854007B2 (en) | Damaged fuel detection method and system | |
| CN214277553U (en) | PH value detection device of vacuum sampling | |
| SU1111056A1 (en) | Device for sampling water-soluble natural gases | |
| CN117809870A (en) | Nuclear sampling system gas sampling device | |
| KR100268039B1 (en) | Sampling device and method for analysis of chemical chemicals for semiconductor | |
| JP4301685B2 (en) | Damaged fuel detection device and detection method thereof | |
| CN117330369A (en) | Finite space gas sampling monitoring system and sampling monitoring method | |
| Frandsen et al. | Barrel RICH: Liquid Transparency Measurement | |
| HU192261B (en) | Apparatus for continuous sampling liquids |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |
Effective date: 20161003 |