RU2347204C1 - Sampling apparatus of liquid radioactive waste from storage capacities on atomic power station - Google Patents

Abstract

FIELD: physics; measuring.

SUBSTANCE: invention concerns to the device for sampling of a fluid and can be used in atomic engineering for the control of a state of the liquid radioactive waste stored on territory of the atomic power station, and also can be used in chemical industry by operation with aggressive liquids. The sampling apparatus of a liquid radioactive waste (LRW) from storage capacities on the atomic power station contains vertically moving massive sampler with outside holes and the interior offtaking channel which is connected by means of a flexible sampling hose with a sampling vessel. The sampling apparatus contains also the vacuum pump connected to the sampling vessel, a resort of fixing of depth of dip sampler in LRW, pipelines and gates for realisation of auxiliary and working sampling/sample selection operations. The sampling apparatus is equipped by the gadget for deactivation and wash of an interior surface of a flexible hose and the interior offtaking channel of the sampler. Thus it is supplied by the hermetic portable cabinet for arrangement of a reserve of the flexible sampling hose which by means of tube drifting, having the mobile trace of the flexible sampling hose, is joined through a vertical branch pipe to an upper of capacity for LRW storage. The vertical branch pipe of penetration piping is equipped by the gadget for deactivation and wash of an outside surface of the flexible hose and the sampler.

EFFECT: decrease of labor input at the expense of reduction of action of radiation at the offered arrangement of knots of the device.

2 cl, 3 dwg

Description

The invention relates to a device for sampling liquids and can be used in nuclear energy to monitor the state of liquid radioactive waste stored in nuclear power plants, and can also be used in the chemical industry when working with aggressive liquids.

A known method of sampling a liquid and a device for its implementation (see RF patent No. 2123679, IPC 6 G01N 1/00 from 07/19/96). The method consists in the fact that a sample of the liquid for analysis is obtained by evacuating the immersion tank. A device for implementing the method comprises a closed container equipped with a retaining element and an intake tip. Since the method and device are designed to monitor the state of neutral or low-toxic liquids, they cannot be used to take samples from the tanks of liquid radioactive waste storage facilities at nuclear power plants.

A device for sampling liquid radioactive waste (LRW) from storage tanks at a nuclear power plant, comprising a massive inlet with a channel connected by a flexible sampling hose to a sampling vessel, the capacity of which is connected to a vacuum pump; means for setting the immersion depth of the sample in the LRW, a system of pipelines and valves for auxiliary and working operations, means for decontamination and washing of the inner surface of the hose (see the VNIIAES Annual Report for 2004, Moscow: Publishing House UNPTs Energomash, 2005, p.95, “Development of documentation, manufacture and implementation of a sampling device for containers of liquid radioactive waste from nuclear power plants”).

A disadvantage of the known device is that during sampling, maintenance personnel must be in the premises for the storage of containers with liquid radioactive waste and work with equipment whose elements cannot be decontaminated and flushed during operation, which significantly increases the personnel dose. In addition, in some cases, the dimensions of the storages do not allow the sampler to be placed in containers with liquid radioactive waste at convenient service distances (primarily along the height of the storages).

The last of the devices has the largest number of common essential features with the proposed and therefore selected as a prototype.

The present invention solves the problem of reducing the dose of maintenance personnel, which is achieved by reducing exposure to radiation in the proposed placement of the device nodes and providing it with a device for decontamination and washing of the outer and inner surfaces of the flexible sampling hose.

To achieve the technical result, a sampler of liquid radioactive waste (LRW) from storage tanks at a nuclear power plant, containing a vertically moving massive intake with external holes and an internal outlet channel, which communicates using a flexible sampling hose with a sampling vessel, a vacuum pump connected to the sampling vessel , means for fixing the depth of immersion of the intake in LRW, pipelines, valves for auxiliary and working sampling operations, device for decontamination and washing of the inner surface of the flexible hose and the internal channel of the intake, it is additionally equipped with a remote sealed chamber to accommodate the reserve stock of the flexible sampling hose, which is connected through a vertical pipe to the upper part of the LRW storage tank using a pipe penetration having a movable trace of the flexible hose and the vertical pipe branch pipe is equipped with a device for decontamination and washing the outer surface of the flexible sampling hose and its obstruction rnika.

Distinctive features of the proposed device from the aforementioned known closest to it is the additional supply of its sealed remote chamber to accommodate the reserve stock of the flexible sampling hose, which is connected through a vertical section to the upper part of the tank through a pipe penetration having a movable trace of the flexible hose storage of LRW, and the vertical pipe branch pipe is equipped with a device for decontamination and washing the outer surface of the flexible sample boron and its intake hose.

In addition, a distinctive feature is that the device for decontamination and washing the outer surface of the flexible hose and the intake is made in the form of a perforated mountain insert, the inner cavity of which is connected to the pressure line of the water supply or decontamination solution and through which the flexible hose can move through by the fence.

Due to the presence of these signs, when sampling from LRW tanks, maintenance personnel remotely control the device while outside the danger zone. In addition, all operations to decontaminate and rinse the intake and its hose are carried out within the LRW tank, which ensures that the already deactivated and washed sampling hose, which is laid for subsequent use, enters the removal chamber, which, along with a reduction in the dosage of maintenance personnel, ensures the convenient operation of the device .

The proposed device for sampling from LRW tanks is illustrated by the drawings and the hydraulic circuit and drawings shown in figures 1-3.

Figure 1 shows the hydraulic circuit of the device.

Figure 2 shows a General view of the device.

3 shows a hose feed assembly (a remote chamber for accommodating a flexible hose reserve).

In figure 1, 2, 3 are shown:

1 - capacity with LRW;

2 - a vertical pipe branch pipe;

3 - pipe penetration;

4 - remote camera;

5 - intake;

6 - outer holes of the intake;

7 - the internal channel of the intake;

8 - flexible sampling hose;

9 - reserve stock of a flexible sampling hose;

10 - sample delivery line;

11 - valve sampling;

12 - manovacuum meter;

13 - detachable connection of the line;

14 - sample receiving line;

15 - drainage pipes of the remote chamber;

16 - valve drainage remote chamber;

17 - hatch remote camera;

18 - hinged bolts of the hatch of the remote chamber;

19 - clamp flexible sampling hose;

20 - boxing;

21 - a sampling vessel;

22 - level gauge;

23 - pressure equalization valve;

24 - valve for supplying the sample to the sampling vessel;

25 - valve for issuing a sample in a measured container;

26 - measured capacity;

27 - a hose of the vacuum pump;

28 - a vacuum pump;

29 - a drainage cap of the box;

30 - pressure purge line;

31 - washer;

32 - bypass water supply line (decontamination solution);

33 - valve external washing flexible sampling hose 8;

34 - water supply valve (decontamination solution);

35 - pressure flushing line;

36 - valve for supplying compressed air.

The sampler is designed for sampling of LRW from a number of tanks that are located in a separate isolated room of the nuclear power plant. Tanks 1 (see FIG. 2) with LRW are made in the form of metal tanks, the necks of which communicate with the ventilation system and additionally have shut-off plugs. All tanks with LRW are equipped with individual means of sampling (see node A1 in figure 1), for which each of them is equipped in its upper part with a vertical pipe 2 (see figure 1) connected by a pipe penetration 3 with a remote sealed chamber 4 , which is mounted on the wall of the adjacent transport corridor (see figure 1 and figure 2). Each tank is equipped with a massive sampling fence 5 with external holes 6 and an internal outlet channel 7, which is suspended on a flexible sampling hose 8 passing through the channel of the pipe penetration 3 with the possibility of longitudinal movement and forming in the volume of the remote sealed chamber 4 a reserve stock 9 of a flexible sampling hose 8 . In line 10 of the issuance of the sample of each individual means of sampling there is a valve 11 of the sampling, vacuum gauge 12 and detachable connection 13, which is used to connect to the line 14 of the reception p Robe mobile means for receiving the sample. The indicated valve 11, the vacuum gauge 12 and the detachable connection 13 are sequentially included in the sample delivery line 10, which begins immediately after the reserve stock 9 of the flexible sampling hose 8.

In the lower part of the remote sealed chamber 4 there is a drain with nozzles 15 and a shutoff valve 16 (see figures 1, 2 and 3).

Access to the volume of the remote sealed chamber 4 is through the hinged hatch 17, which has a sealing seal and pressure hinged bolts 18 (see figure 3). The upper part of the remote sealed chamber 4 at the junction of it with the pipe penetration 3 is equipped with a clamp 19 of a flexible sampling hose 8, which, after measuring the required length and pull through the pipe penetration 3 (due to the weight of the intake 5) serves to fix the suspension of the intake 5 at a selected container height one.

A mobile means for receiving a sample (see assembly A2 in FIG. 1) is common to all the fences 5 and therefore is transported alternately to the attachment point of the sealed remote chamber 4 of the corresponding LRW tank, where its sample receiving line 14 is connected using a detachable connection 13 with line 10 of the issuance of the sample.

A mobile means for receiving a sample (see assembly A2 in FIG. 1) contains a transported box 20, in which a sampling vessel 21 with a level gauge 22 connected to its cavity, a pressure equalization valve 23, a valve 24 for supplying a sample to a sampling vessel 21, a valve 25 is placed the issuance of the sample in the measuring container 26, the pipeline 27 of the vacuum pump 28. In addition, the bottom of the box 20 is equipped with a drainage that contains a drain plug 29.

In the process of sampling, a mobile means for receiving the sample (node A2) is transported and installed under the remote sealed chamber 4 from the tank 1, which is sampled. After connecting the detachable connection 13, both means (see node A1 and node A2 in figure 1) are a single device, the control valves of which are located on a remote sealed chamber (right), mounted on the wall of the transport corridor (see figure 3), and partially placed in box 20, which ensures their compact placement and ease of use.

For decontamination, washing the outer surface of the flexible sampling hose 8 in the vertical nozzle 2 of each tank 1, washers 31 are installed, made in the form of a perforated mountain ring, through which the flexible sampling hose is passed through the central hole 8. The inner cavity of the washer 31 is connected to the water outlet pipe (deactivating solution) 32, which is connected through an external flushing valve 33 and a water supply valve (decontamination solution) 34 to a flushing pressure line 35.

For decontamination, washing the inner surface of the flexible sampling hose 8, each of the sampling means (assembly A1) is connected to the pressure line 35 by means of water supply valves 34 and the sampling valve 11 connected in series, while the remaining valves of the sampling line 10 are closed.

To purge the flexible sampling hose 8, the sampling line 10 through the sampling valve 11 and the air supply valve 36 are connected to the compressed air line 30, all other valves of the line 10 are closed.

For decontamination, washing the inner surface of the vessel 21 and its lines, the means for receiving the sample (node A2) must be connected to one of the means for collecting the sample (node A1) by assembling a detachable connection 13. To create a washing line, use the supply valve 34 water, a valve 24 for supplying a sample, and when draining, a valve 25 is used to dispense a sample and a drain plug 29, i.e. only valves and piping are used, which are available in the means for receiving (node A2) and sampling (node A1) samples without introducing additional devices and devices.

The device operates as follows.

Before starting work, a mobile means for receiving a sample (node A2) is moved and installed under an external sealed chamber 4 of one of the containers 1 from which the sample is taken. After that, the detachable connection 13 is connected and the lines of the sampling means (node A1) and reception (node A2) of the sample are combined. Then open the hatch 17 of the remote sealed chamber 4 and open the valve 11 of the sampling. By loosening the clamp 19, lower the intake 5 to the required level. At the same time, open the valve 36 for air supply (minimum) and thereby prevent the entry of LRW into the hose 8 of the intake 5. Press the hose 8 with the clamp 19 and close the valve 36 of the air supply, while the valve 24 of the sample supply is open, and the valve 23 of the pressure equalization valve 25 the issuance of the sample in the measuring container, the valve 33 flushing the outer surface of the hose, the valve 34 water supply valve 11 sampling closed. Turn on the vacuum pump 28 and create a vacuum in the sampling vessel 21 of at least 0.075 MPa (0.75 kg / cm ² ), which is monitored by a vacuum gauge 12. Then open the sampling valve 11 and fill the sampling vessel 21 LRW to the risk level on the level gauge 22. When the risk level is reached, the sample valve 24 is closed and the vacuum pump 28 is turned off. Open the pressure equalization valve 23 and control the pressure equalization in the sampling vessel 21 with the atmospheric pressure gauge 12. Open the valve 25 for the issuance of the sample in the measuring tank 26 and fill it with the LRW sample. The end of the issuance of the sample is controlled by the level gauge 22, after which the pressure equalization valve 23 and the sample issuance valve 25 are closed. If it is necessary to take a sample from a different mark, the intake 5 should be set to the desired mark and repeat the indicated operations. If the work is completed, the air supply valve 36 is opened and purged at a pressure of 0.03-0.04 MPa (0.3-0.4 kg / cm ² ) sampling line 10, hose 8 and intake 5 for 15-20 seconds whereupon the sampling valves 11 and the air supply 36 are closed.

Washing of the outer surface of the hose 8 is carried out when lifting the intake 5, for which the clamp 19 is loosened, the flexible sampling hose 8 is pulled out of the pipe penetration 3 and laid in the portable chamber 4 in the form of a compact bay, whereby the water supply valve 34 and the external flushing valve 33 are first opened. the surface of the hose 8. Rinsing is carried out with water or a decontamination solution, which are discharged into one of the tanks 1, after which the hose 8 is fixed with a clamp 19 in the position in which the intake 5 is placed in the cavity of the vertical path cabin 2, and the valve 33 washing the outer surface of the hose 8 is closed.

As required and using standard valves, the sampling vessel 21 and the associated pipelines are washed and deactivated.

Thanks to the external washing and deactivation of the flexible sampling hose 8 and the remote maintenance of the tanks with LRW, maintenance personnel receive lower radiation doses, which reduces their dose costs.

Claims (2)

1. A sampler of liquid radioactive waste (LRW) from storage tanks at nuclear power plants, containing a vertically moving massive intake with external holes and an internal outlet channel, which communicates using a flexible sampling hose with a sampling vessel, a vacuum pump connected to the sampling vessel, a fixation tool immersion depths of the intake in LRW, pipelines, valves for auxiliary and working sampling operations, a device for decontamination and washing of the internal surface and a flexible hose and an internal outlet channel of the intake, characterized in that it is equipped with a sealed remote chamber for accommodating the reserve stock of the flexible sampling hose, which is connected through a vertical pipe to the upper part of the LRW storage tank using a pipe penetration having a movable trace of the flexible sampling hose, moreover, the vertical pipe fitting is equipped with a device for decontamination and washing the outer surface of the flexible hose and intake. 2. A sampler of liquid radioactive waste (LRW) from storage tanks at the nuclear power plant according to claim 1, characterized in that the device for decontamination and washing the outer surface of the flexible hose and the intake is made in the form of a perforated toroidal insert, the inner cavity of which is connected to the pressure line of the water supply or a decontamination solution and through the central opening of which a flexible hose with a fence can move.

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