JP4492880B2 - Method for cleaning sodium-using facility and method for manufacturing sodium dispersion by performing cleaning and manufacturing sodium dispersion - Google Patents

Description

  The present invention relates to a method for cleaning sodium-using facilities.

  Conventionally, it is used for dehalogenating and decomposing organic halogen compounds such as polychlorinated biphenyls contained in electrical insulating oil, heat medium, organic waste liquid, etc., and as a synthesis reagent for organic compounds and inorganic compounds. In this case, a sodium dispersion in which metallic sodium is made into fine particles and dispersed in a dispersion medium is used.

  As a method for producing such a sodium dispersion, generally, metallic sodium in a liquid state (hereinafter also simply referred to as “sodium”) heated to a temperature equal to or higher than the melting point, and an oil inert to the metallic sodium. Many methods are used in which sodium is dispersed into fine particles by stirring the dispersion medium using (inert oil) at high speed in a stirring tank. For example, Patent Document 1 below describes a method for producing a sodium dispersion by dispersing metallic sodium in trans oil.

  In the production of such a sodium dispersion, a sodium dispersion part in which liquid metal sodium and a dispersion medium are stirred to disperse sodium in the dispersion medium, such as a stirring tank, and metal sodium supplied to the sodium dispersion part A sodium storage part equipped with a facility such as a sodium storage tank for storing liquid in a liquid state, a pipe for transporting liquid metallic sodium from the sodium storage part to the sodium dispersion part, a pump serving as transport power, etc. The equipment comprised by the sodium conveyance piping part with which it was equipped is used conventionally.

By the way, it is known that metallic sodium is a solid at normal temperature and has high reactivity. For example, it is known to react with water to generate hydrogen, and this reaction between metallic sodium and water is also known to occur between metallic sodium and moisture in the air.
For this reason, metallic sodium is stored in oil in order to prevent contact with substances that react with metallic sodium, such as moisture.
In addition, in the above-mentioned sodium dispersion manufacturing facilities, sodium battery manufacturing facilities, or sodium-using facilities that use sodium as a heat transfer medium, the metallic sodium used is strictly controlled and stored. Have been.
However, when using metallic sodium in the sodium-using equipment as described above, for example, in components used for transporting metallic sodium in the sodium dispersion manufacturing equipment and components such as valves provided in this pipe If the molten metal sodium remains, the metal sodium may cool and solidify later, which may cause clogging of the pipe or may react at this adhesion point. Furthermore, there is a possibility that it may be transformed into a sodium salt or the like by the reaction.

On the other hand, conventionally, in this sodium-using facility, the component is periodically disassembled and the metallic sodium-attached component parts are scrubbed with a burner or the like to melt and remove the metallic sodium, or the component parts and water are removed. It is made to contact and react, and it wash | cleans and removes as sodium hydroxide.
However, there is a danger that sodium vapor is generated when the treatment is performed with this burner, and there is a danger that a large amount of hydrogen gas is generated when the amount of metallic sodium attached is large even in contact with water. Therefore, the work is dangerous and requires careful work.

JP-A-10-110205

  This invention is made | formed in view of the above problems, and makes it the subject to provide the washing | cleaning method of the sodium use installation which can remove sodium from a sodium use installation by a safer and simple method than before.

  In order to solve the above-mentioned problem, the present invention is used in a sodium-using facility where metallic sodium is used, and the components of the sodium-using facility to which metallic sodium is attached are washed with an inert oil having a temperature equal to or higher than the melting point of sodium. Thus, a method for cleaning sodium-using equipment is provided, in which the attached metallic sodium is removed.

  In addition, the inert oil in this specification is sufficiently low in reactivity with metallic sodium, such as mineral oil used for storage of metallic sodium in oil or used as a dispersion medium for sodium dispersion, It is intended to be an oil that does not cause practical problems such as significant deterioration of metallic sodium and this inert oil when contacted with metallic sodium at a temperature above the melting point of metallic sodium.

According to the present invention, the metallic sodium adhering to the component parts of the sodium-using equipment in which metallic sodium is used is washed with an inert oil having a temperature equal to or higher than the melting point of sodium, so that it adheres to the constituent parts of the sodium-using equipment. The metallic sodium present can be removed in a molten state. Moreover, since this metallic sodium can be melted and removed in an inert oil, sodium vapor is generated as if it is burned with a burner, or a large amount of hydrogen gas is generated as if it is washed with water. Can be suppressed.
Therefore, sodium can be removed from facilities using sodium by a safer and easier method than before.

In the following, a preferred first embodiment of the present invention will be described using sodium dispersion production equipment as an example of sodium use equipment.
(First embodiment)
In the sodium dispersion production facility of this embodiment, an inert oil is used for the dispersion medium of the sodium dispersion and the washing of the sodium dispersion production facility. The dispersion medium of this sodium dispersion and the inert oil for washing the sodium dispersion production equipment have a density of 0.85 to 0.87 g / cm ³ , a flash point of 140 ° C. or higher, a pour point of −20 ° C. or lower, and 40 ° C. It consists of paraffinic mineral oil with a kinematic viscosity of 7-9 mm ² / s, an acid value of 0.01 mgKOH / g or less, a sulfur content of 1 ppm or less, a paraffin chain carbon content of 50% or more, and an aromatic ring carbon content of 15% or less. Electrical insulating oils, lubricating oils, etc., of Class 4 and 3 petroleum can be suitably used.
First, referring to FIG. 1, a sodium dispersion manufacturing facility in the case where an electrical insulating oil (hereinafter also referred to as “insulating oil”) using paraffinic mineral oil as described above is used as the dispersion medium will be described. I will explain.

The sodium dispersion production facility of the present embodiment includes a sodium dispersion unit 3 in which metallic sodium in a liquid state is stirred together with a dispersion medium in order to form a sodium dispersion in which sodium is dispersed in the dispersion medium. A sodium reservoir 1 having a sodium reservoir 11 in which metal sodium is stored in a liquid state so as to supply metal sodium in a liquid state to the sodium dispersion portion 3, and a liquid state from the sodium reservoir 1 to the sodium dispersion portion 3 A sodium transport pipe portion L1 having a pipe for transporting metallic sodium is provided.
In addition, the sodium dispersion manufacturing facility of the present embodiment has an insulating oil storage section (dispersion medium storage section) having an insulating oil storage tank (dispersion medium storage tank) 21 that stores an insulating oil serving as a dispersion medium for the sodium dispersion. 2 and the sodium dispersion storage part 4 which stores the sodium dispersion formed by the sodium dispersion part 3 is provided.

In the present embodiment, the sodium reservoir 1, the insulating oil reservoir 2, the sodium dispersion portion 3, and the sodium dispersion reservoir 4 are respectively installed in separate buildings, and the sodium reservoir 1 and the sodium dispersion portion 3 A sodium flow path is formed by the sodium transport pipe L1 so that a sodium transport pipe L1 is provided between the sodium reservoir 1 and the sodium dispersion part 3 in a liquid state. In addition, an insulating oil transport pipe section (dispersion medium transport pipe section) L2 is provided between the insulating oil storage section 2 and the sodium dispersion section 3, and the sodium dispersion between the sodium dispersion section 3 and the sodium dispersion storage section 4 is provided. The body conveyance piping part L3 is provided.
Furthermore, in the present embodiment, a bypass piping portion Lb that connects the insulating oil transport piping portion (dispersion medium transport piping portion) L2 and the sodium transport piping portion L1 is provided.

The sodium reservoir 1 is provided with a sodium reservoir 11 having a capacity of, for example, several tens of m ^{3 in} order to store metallic sodium in a liquid state.
Further, the sodium reservoir 1 has a pressurized nitrogen supply device 12 as a pressurizing mechanism for pressurizing liquid metallic sodium stored in the sodium reservoir 11 and the sodium reservoir from the pressurized nitrogen supply device. The tank 11 is provided with a nitrogen supply pipe for conveying pressurized nitrogen.

  As the pressurized nitrogen supply device 12 of the pressurizing mechanism, for example, a nitrogen generating device that generates pressurized nitrogen gas, a nitrogen tank that stores nitrogen generated by the nitrogen generating device in a pressurized state, and the like Can be configured. Further, if necessary, a backup of the nitrogen generator can be performed by using a nitrogen gas cylinder connected to the nitrogen supply pipe in addition to the nitrogen generator. In addition, the nitrogen gas generating apparatus uses, for example, a so-called Pressure Swing Adsorption (hereinafter also referred to as PSA) method, which uses an adsorbent that adsorbs a substance to be separated in a high pressure state and releases it in a low pressure state. What was comprised so that the gas contained other than nitrogen could be made to adsorb | suck to an adsorbent and the highly purified nitrogen could be taken out can be used. As this PSA type nitrogen generator, two or more adsorption towers are provided, one adsorption tower is placed in a high pressure state, a gas other than nitrogen is adsorbed on the adsorbent, and the high pressure state nitrogen is discharged from this adsorption tower. It is preferable that the adsorption tower is placed in a low pressure state to discharge oxygen and the like adsorbed on the adsorbent, and the high pressure state and the low pressure state can be alternately performed to continuously extract pressurized nitrogen. is there. Moreover, as a PSA type | system | group nitrogen generator, what can make the pressure of the discharge | emission (stored in a nitrogen tank) the pressure of several hundred kPa can be used, for example.

  Furthermore, this pressurization mechanism can be provided with a mechanism for controlling the supply of pressurized nitrogen to the sodium reservoir by the amount of sodium supplied from the sodium reservoir 11 to the sodium dispersion part 3, and as this control mechanism Is, for example, a liquid level gauge that detects the amount of sodium stored in the sodium storage tank 11 (the amount of sodium delivered from the sodium storage tank), and PID control using a detection signal from the liquid level gauge. A flow rate adjusting valve that adjusts the flow rate of the pressurized nitrogen can be used.

The said sodium storage tank 11 is formed so that a tank main body is comprised by the cover part and the main-body part, and can hold the content in the state which maintained the pressure state of the content.
The sodium body of the sodium storage tank 11 has a sodium inlet for introducing metal sodium carried in a tank lorry or the like into the sodium storage tank, and nitrogen into which pressurized nitrogen from the pressurized nitrogen supply device is introduced. An inlet is opened, the sodium inlet is connected to a tank truck or the like through a pipe, and the nitrogen inlet is connected to a pressurized nitrogen supply device 12 through the pipe.
Further, the wall of the main body portion is formed in a double shape to form a jacket structure, and this jacket structure portion is used to maintain the liquid state by heating the metallic sodium stored in the sodium storage tank 11 to 120 ° C., for example. It is formed so that a heat medium such as oil can be circulated.
Furthermore, one end of the pipe of the sodium transport pipe is opened near the bottom of the main body.

The pipe of the sodium transport pipe L1 is arranged from the building where the sodium reservoir 1 is arranged to the building where the sodium dispersion part 3 is arranged, and metallic sodium is supplied from the sodium reservoir 11 to the sodium dispersion part 3. It is insulated by a heat insulating material so as to be conveyed while being maintained in a liquid state.
The sodium transport piping portion L1 can be provided with a flow rate measuring device for measuring the flow rate of sodium flowing through the piping used for transporting the sodium.
Moreover, this sodium conveyance piping part L1 is not provided with conveyance power, such as a pump for conveying sodium.
As a result, the formation of the joining portion in the sodium transport piping portion L1 can be suppressed, the leakage of sodium can be suppressed, and the labor required for equipment maintenance can be reduced.

The insulating oil reservoir 2 is provided with an insulating oil reservoir 21 having a capacity of, for example, several tens of m ^{3 in} order to store the insulating oil.
In this insulating oil storage tank 21, one end of the pipe of the insulating oil transport pipe L2 is opened.

The piping of the insulating oil transfer piping part L2 whose one end is opened in the insulating oil storage tank 21 is arranged from the building where the insulating oil storage part 2 is arranged to the building where the sodium dispersion part 3 is arranged. The other end of the sodium dispersion part 3 is opened.
In addition, the insulating oil transfer piping section L2 has a flow rate measuring device (not shown) for measuring the flow rate of the insulating oil flowing through the pipe used for transferring the insulating oil, and an insulating oil transfer pump for transferring the insulating oil ( Dispersion medium transport pump) P1 and a heat exchanger EX for heating the insulating oil are provided.

  One end of the pipe of the bypass pipe Lb is opened near the outlet from the sodium storage tank 11 of the sodium transport pipe L1, and the other end of the bypass pipe Lb is downstream of the heat exchanger EX of the insulating oil transport pipe L2. The sodium conveyance piping part L1 and the insulating oil conveyance piping part L2 are connected in the state opened to.

The sodium dispersion part 3 includes a primary dispersion device in which sodium is primarily dispersed to an average particle size of, for example, about 20 μm, and a sodium primary dispersion dispersed in the primary dispersion device having an average sodium particle size of about 5 μm. A plurality of secondary dispersion devices for further dispersing so as to be a sodium secondary dispersion are provided.
In addition, the sodium dispersion unit 3 is provided with a sodium buffer tank 30 for temporarily storing the metal sodium in a liquid state conveyed by the sodium conveyance piping unit L1 before supplying it to the primary dispersion device 31. The other end of the sodium transport pipe L1 is opened to the sodium buffer tank 30 and the other end of the insulating oil transport pipe L2 is opened to the primary dispersion device 31. The apparatus 31 introduces sodium from the sodium buffer tank 30 and introduces insulating oil from the insulating oil transport pipe L2 to produce a primary dispersion of sodium and dispersion medium (hereinafter also referred to as “sodium primary dispersion”). Configured to get.

The sodium dispersion part 3 stores the sodium primary dispersion dispersed in the primary dispersion device 31 or repeatedly passes the sodium primary dispersion through the secondary dispersion device 32 to obtain the sodium secondary dispersion. A plurality of buffer tanks 33 having a capacity of, for example, about 2 to ³ m ³ are provided for storing the sodium dispersion once passed through the secondary dispersion device.

Further, the sodium dispersion part 3 is provided with a sodium dispersion cooling tank 34 for cooling the sodium secondary dispersion formed in the secondary dispersion device 32 so that the average particle diameter of sodium is about 5 μm below the melting point of sodium. The sodium dispersion cooling tank 34 has a capacity of about 10 m ^{3, and the} tank wall is doubled to form a jacket structure. And it forms so that refrigerant | coolants, such as oil, can distribute | circulate to this jacket structure part.
Further, the sodium dispersion cooling tank 34 is provided with a stirring mechanism so as to suppress the precipitation of sodium while making the temperature in the tank uniform.

As the primary dispersion device 31, for example, a stirring device including a paddle blade, a disk turbine blade, or the like can be used.
In addition, this stirrer maintains an appropriate temperature of the sodium dispersion during primary dispersion, such as oil to prevent the temperature of the sodium dispersion from rising too high and exceeding the flash point of the insulating oil. It is preferable to use an agitation tank in which a jacket structure capable of circulating the heat medium is formed. In particular, a synthetic heat transfer oil that is inactive to sodium can be suitably used as the oil in that sodium can be prevented from reacting even when sodium leaks into the jacket portion.

  Further, as the secondary dispersion device 32, a high discharge type and a high shear type are used, and these are arranged in series so as to be a high discharge type on the upstream side and a high shear type on the downstream side. Yes. As the high discharge type secondary dispersion device 32A, for example, as shown in FIGS. 2 and 3, a plurality of blades are erected in the circumferential direction, and the plurality of blades are formed in a plurality of concentric rows. A rotor formed to be rotatable around the center of the concentric circle and a stator having blades formed in a plurality of concentric circles in the same manner as the rotor are arranged so as to face each other and rotate by rotation of the rotor. A dispersing device is used in which sodium is sheared and refined by blades of a rotor and a stator.

In this rotor, a plurality of concentric blades as described above are formed on the front surface side of a disk-shaped main body, and a rotating shaft for rotating the rotor is fixed at the center on the back surface side.
In addition, the rotor has a swept wing formed at the center thereof, and centrifugal force acts on the sodium dispersion by rotation, and the sodium dispersion that receives this centrifugal force is arranged on the outer peripheral side of the swept wing. It is formed to function in the same way as a homogenizer that is sheared by a large number of blades. And this rotor is accommodated in the housing | casing in which the cylindrical space slightly larger in diameter than the said disk-shaped main body and slightly thicker than a rotor was formed. The casing that accommodates the rotor has an opening surface formed in one of the cylindrical spaces and a closed surface formed in the other, and a through hole through which the rotating shaft is inserted is formed in the closed surface. The opening surface has a flange formed on the outer periphery of the opening. In addition, a discharge hole is formed on the side surface of the casing so as to communicate the inside of the casing with the outside in order to discharge the sodium dispersion dispersed in the casing to the outside of the casing.
And this rotor is accommodated in a housing | casing, making the back surface side of a disk-shaped main body contact the said obstruction | occlusion surface.
The rotor is housed in such a housing and is rotatable relative to the housing, and can be rotated in the housing by the rotating shaft.

  In the stator, a flange formed on the outer peripheral portion of the opening surface of the rotor and a flange formed so as to be able to be locked are formed on an outer edge portion. When the flange between the stator and the rotor is brought into contact, the flange is formed. The concentric blades of the stator are arranged so as to protrude from the contact surface toward the rotor and be positioned between the concentric blades arranged on the rotor surface. In addition, this stator penetrates from the front side to the back side where concentric blades are formed in the center of the stator so that a sodium dispersion primarily dispersed in the center of the stator (rotor) can be introduced. A through-hole (suction hole) is formed.

Further, in the high shear type secondary dispersion device 32B, for example, the blade area of the swept wing formed in the central portion of the rotor is reduced or not provided, and the number of blades to which the sodium dispersion is sheared is reduced. The shear performance is improved as compared with the high discharge type secondary dispersion device.
In these secondary dispersion devices, a jacket structure is formed outside the device as in the case of the primary dispersion device described above.

  In this sodium dispersion part 3, one end of the pipe is connected to the sodium dispersion cooling tank 34 in order to supply the formed sodium dispersion to the sodium dispersion storage part 4 through the pipe of the sodium dispersion transport pipe part L3. It is connected.

The sodium dispersion reservoir 4 is provided with a plurality of sodium dispersion reservoirs 41 having a capacity of, for example, several tens of m ³ , and the sodium dispersion reservoir 41 is provided with the sodium dispersion reservoir 41. The other end of the pipe is connected.
Further, a discharge pipe for discharging the sodium dispersion is connected to the sodium dispersion storage tank 41, and supply to a tank truck or the like can be appropriately performed through the discharge pipe.
In addition, the sodium dispersion storage tank 41 is also provided with a stirring mechanism in order to suppress sodium sedimentation.

  Although not described in detail here, the sodium dispersion facility of this embodiment includes a general sodium dispersion facility such as an electric heater, a temperature control device such as steam, a mechanism for controlling the flow of valves, valves, and the like. The apparatus and mechanism used for the body manufacturing facility can be employed as long as the effects of the present invention are not impaired.

Next, a sodium dispersion manufacturing method using such a sodium dispersion manufacturing facility will be described.
First, the metallic sodium stored in the sodium storage tank 11 of the sodium storage section 1 is heated to a temperature of 120 ° C., for example, by circulating a heat medium through the jacket section of the sodium storage tank 11, and sufficient to maintain the temperature. A liquid state having fluidity is set, the sodium storage tank 11 is sealed, and pressurized nitrogen is supplied to the sodium storage tank 11 from the pressurized nitrogen supply device 12 of the pressurizing mechanism. Pressurize metallic sodium.

Due to the pressurization of the metallic sodium by the pressurized nitrogen, the metallic sodium in the sodium storage tank is pumped to the sodium buffer tank 30 through the sodium transport pipe section L1.
At this time, depending on the pipe length of the sodium transport pipe L1, the pipe diameter, the height difference between the start point and the end point, etc., for example, pressurized nitrogen is supplied to the sodium storage tank, and the pressure of nitrogen in the sodium storage tank 50 to 100 kPa (for example, 70 kPa) or the like, for example, sodium can be pumped to a point at a distance of several tens of meters or more through the sodium transport piping portion L1 using 2B piping.
Thus, when the pressurized gas is used, when the pressure is fed to the primary dispersion device through the sodium transport pipe, the pressure in the sodium storage tank can be gradually changed, and the flow rate can be easily adjusted. . Moreover, since nitrogen that is inert to sodium is used as the pressurized gas, it is safe and there is no risk of degrading the quality of the sodium dispersion. Furthermore, since nitrogen is inexpensive, these effects can be obtained at a low cost.

  At this time, sodium adheres to the components constituting the sodium transport pipe L1 such as pipes and valves of the sodium transport pipe L1 after the sodium circulates, and the attached sodium eventually decreases in temperature and becomes a solid state. The cleaning and removal method will be described later.

  Next, a predetermined amount of sodium is supplied from the sodium buffer tank 30 to the primary dispersion device 31, and from the insulating oil reservoir 2, the piping of the insulating oil transfer piping portion L2 by the transfer power of the insulating oil transfer pump P1. Insulating oil is supplied to the primary dispersion device 31 through the through-holes. At this time, the insulating oil is heated to, for example, a temperature of 120 ° C. and supplied to the primary dispersion device 31 by the heat exchanger EX provided in the insulating oil transfer piping section L2.

In the primary dispersion device 31, the introduced insulating oil and metallic sodium are mixed and stirred to form a sodium primary dispersion having an average particle diameter of sodium of 20 μm or less. At this time, since frictional heat is generated in the insulating oil and metallic sodium and the temperature rises normally, the jacket structure having the jacket structure as described above is used, and the jacket structure is 105 to 140. It is preferable to form a sodium primary dispersion while circulating a synthetic heat transfer oil or the like maintained at a temperature of ° C to maintain the internal temperature at, for example, 120 ° C.
That is, before the primary dispersion, the sodium introduced into the primary dispersion device 31 is prevented from having a melting point (98 ° C.) or less by the circulation of the synthetic heat transfer oil, and after the primary dispersion is started, heat is generated by frictional heat. The insulating oil is prevented from becoming a high temperature exceeding 150 ° C., for example, by the circulation of the synthetic heat transfer oil.

  In addition, the particle diameter of sodium in the present specification intends the diameter of a perfect circle having the same area as the projected area of sodium particles measured using an optical microscope or the like for the sodium dispersion, and the average of sodium The particle size is intended to be a value obtained by arithmetically averaging the particle sizes obtained by obtaining the particle size of particles that can be visually observed when the sodium dispersion is magnified 200 times.

  Subsequently, the sodium primary dispersion obtained in the primary dispersion device 31 is temporarily stored in the buffer tank 33, and the sodium primary dispersion is supplied from the buffer tank 33 to the high discharge type secondary dispersion apparatus 32A to further refine the sodium. Then, sodium is further refined and dispersed by the high shear type secondary dispersion device 32B arranged in the next stage of the high discharge type secondary dispersion device 32A.

More specifically, the sodium primary dispersion is sucked from the buffer tank 33 through the suction hole of the high discharge type secondary dispersion device 32A, and the rotor is rotated, so that the sodium dispersion sucked from the suction hole is removed from the rotor. A centrifugal force is applied by a retreating blade provided in the center portion to pass between the blades of the rotor and the stator and move outward, while shearing is applied by the blades of the rotor and the stator. And a sodium dispersion is discharged | emitted from the said discharge hole, and it introduce | transduces into the high shear type | mold secondary dispersion apparatus 32B, and refines | miniaturizes a sodium particle further. Next, the sodium dispersion discharged from the high shear type secondary dispersion device 32 </ b> B is refluxed to the buffer tank 33.
As described above, the high discharge type secondary dispersion device 32A and the high shear type secondary dispersion device 32B are used in combination, so that the sodium particles can be efficiently refined, and the sodium dispersion such as a pump can be conveyed. Therefore, it is possible to obtain an effect that it is possible to omit equipment for the purpose.

  In this way, the sodium dispersion is removed from the buffer tank 33 until the sodium particles of the sodium dispersion have a desired particle size, for example, a particle size of 5 μm or less, and the high shear type secondary dispersion device 32A and the high discharge type secondary dispersion device. Reflux to buffer tank 33 via 32B.

When the sodium particles have a desired particle size, the sodium dispersion flow path from the high discharge type secondary dispersion device 32B to the buffer tank 33 is switched to the sodium dispersion cooling tank 34, and the sodium dispersion Is stored in the sodium dispersion cooling tank 34.
At this time, a pressurized gas such as nitrogen may be introduced into the buffer tank 33 so that the sodium dispersion in which the sodium particles have a desired particle diameter is pumped to the sodium dispersion cooling tank 34. In this way, by introducing a pressurized gas such as nitrogen into the buffer tank 33 and feeding the sodium dispersion to the sodium dispersion cooling tank 34, sodium can be quickly obtained as compared with the case where the secondary dispersion apparatus is made to flow by the discharge force. The dispersion can be moved to the sodium dispersion cooling tank 34, and a sodium dispersion having a desired particle size can be suppressed from remaining in the system, thereby providing a more efficient operation method.
At this time, a coolant is circulated through the jacket of the sodium dispersion cooling tank 34 to cool the sodium dispersion to about 25 ° C., for example.

  The sodium dispersion cooled in the sodium dispersion cooling tank 34 is stored in the sodium dispersion storage tank 41 of the sodium dispersion storage section 4 through the pipe of the sodium dispersion transport pipe section L3.

In this way, after the production of the sodium dispersion for one batch is completed, the insulating oil having a melting point of sodium (98 ° C.) or higher is circulated through the pipe constituting the sodium transport pipe portion L1 used as the sodium flow path. Thus, an oil circulation washing step is carried out for washing and removing sodium adhering to the pipe of the sodium transport pipe section L1 or a valve provided in the pipe.
That is, the melting point of sodium is such that the path of the insulating oil is introduced from the insulating oil storage tank 21 through the heat exchanger EX and the bypass pipe section Lb to the sodium transport pipe section L1 and introduced into the sodium buffer tank 30. The above-mentioned insulating oil is circulated through the sodium transport piping portion L1 so that the attached sodium is washed away.

At this time, the insulating oil is preferably heated to a temperature of 120 to 140 ° C. by the heat exchanger EX so as to circulate in the pipe of the sodium transport pipe section L1.
In addition, if necessary, a reflux pipe connecting the sodium buffer tank 30 to the vicinity of the outlet of the sodium storage tank 11 of the sodium transport pipe section L1, and the insulating oil introduced into the sodium buffer tank 30 are circulated through the reflux pipe. Insulating oil can be circulated through the sodium buffer tank 30, the reflux pipe, and the sodium transport pipe L1.

The insulating oil after this oil circulation washing step can be discharged out of the system and treated separately, or can be used as it is for the production of the sodium dispersion of the next batch.
By producing the sodium dispersion while carrying out the oil circulation washing process in this way, it is possible to prevent clogging due to sodium adhering in the sodium transport piping part L1, and the sodium reacts to generate heat locally. Or it can suppress that a sodium salt is mixed with a sodium dispersion, and can suppress the fall of the quality of a sodium dispersion.
Moreover, by performing in-line cleaning in this way, sodium cleaning can be performed more easily and safely than when disassembling the sodium dispersion production facility to remove sodium. In addition, sodium can be removed without contacting sodium and air without requiring a decomposition operation, and the production efficiency of the sodium dispersion can be improved.

Here, the case where the oil circulation washing process is performed for each batch of sodium dispersion production has been described as an example. However, for example, this oil circulation washing is performed only after the production of the sodium dispersion of the final batch of the day. A process can also be carried out.
Further, in the present embodiment, the method for cleaning sodium-using equipment has been described by way of example in the case of producing a sodium dispersion as described above using the sodium dispersion-producing equipment configured as described above. The sodium dispersion manufacturing facility is not limited to the above.

For example, as shown in FIG. 4, the sodium buffer tank and the primary dispersion device are not used, and the liquid sodium supplied from the sodium storage tank 11 and the insulating oil supplied from the insulating oil storage tank 21 directly It can also be used in a sodium dispersion manufacturing facility that is configured to be introduced into the buffer tank 33 and stored.
Further, in the present invention, the sodium use facility is not limited to such a sodium dispersion production facility.

  Further, in the present embodiment, the case where the same insulating oil as the dispersion medium of the sodium dispersion is used as an example of the inert oil used for washing the sodium dispersion production equipment is that it can be used as the dispersion medium of the sodium dispersion. However, in the present invention, the inert oil is not limited to the same dispersion medium as the sodium dispersion.

(Second embodiment)
Next, a second embodiment will be described with reference to FIG.
In this embodiment, the oil immersion that removes the attached sodium by separating the component with sodium attached from the facility using sodium and immersing it in an inert oil heated above the melting point of sodium in the oil tank. In the point which implements a washing | cleaning process, it differs from 1st embodiment which implements the oil circulation washing | cleaning process which distribute | circulates the inert oil of the temperature more than the melting | fusing point of sodium to a sodium distribution channel.

First, equipment used in the oil immersion cleaning process of the second embodiment will be described.
In this oil immersion cleaning process, an oil tank 5 formed to accommodate the inert oil F used for cleaning and the component A to be cleaned is used.
The oil tank 5 has a housing space having a substantially horizontally long rectangular parallelepiped shape formed therein, and a bottom surface 51 of the oil tank 5 is formed so as to be inclined from one side of the horizontally long rectangular solid shape to the other end side. An oil discharge hole 52 for discharging the inert oil F from the tank bottom is formed.
Further, the inclined bottom surface 51 is provided with a region projecting upward from the bottom surface so that the component to be cleaned is placed at a position above the oil discharge hole. A placement portion 53 is formed, and the placement portion 53 is formed such that the upper surface 53A is substantially horizontal.

Further, the oil tank 5 is formed with a heating wall 55 for heating the inert oil F accommodated therein to a melting point of sodium or higher by heat transfer from the inner wall surface 54, and the inert oil in the oil tank 5 is formed. In order to make the temperature of F uniform, an agitation mechanism 6 for agitating the inert oil F is provided, and the temperature of the inert oil F is measured to determine the warming state on the heating wall 55. A temperature control mechanism 7 for controlling is provided.
Further, the oil tank 5 is sprayed with a cleaning liquid for further cleaning the component A after being immersed in an inert oil F heated to a temperature higher than the melting point of sodium and then removing sodium. An injection nozzle 8 is provided.

As a heating means for the heating wall 55, a means for forming a jacket structure 55A on the tank wall so that a heat medium can be circulated, or an electric heater is embedded in the tank wall can be used.
Moreover, it can replace with this heating wall, heating of an inert oil can also be implemented with heating means, such as a throwing heater, and it is also possible to use these heating means in combination.
In addition, it is possible to introduce a preheated inert oil into the oil tank without providing an inert oil heating means in the oil tank.

  As the stirring mechanism 6, a general stirring mechanism 6 in which a propeller stirring blade 61 or the like is rotated by a motor 62 and stirred is used. In place of the stirring mechanism such as the propeller stirring blade, the inert oil in the tank is sucked and sprayed along the tank wall to cause the inert oil in the tank to flow in the circumferential direction, or A stirring mechanism for bubbling the inside of the tank using a gas inert to sodium such as gas can be used.

The temperature control mechanism 7 includes a temperature detection device such as a sheath thermocouple 71 and a temperature sensor for measuring the temperature in the tank, and a signal from the temperature detection device is fed back to the heating means of the heating wall. It can be constituted by a control device (not shown) for controlling the temperature state.
As this control device, for example, the current value of the heating heater of the heating wall is controlled by PID control using a microcomputer, or the temperature and flow rate of the heat medium flowing through the jacket structure of the heating wall is controlled. Can be used.

  The spray nozzle 8 depends on the type of cleaning liquid used for cleaning the component parts. For example, a plurality of nozzles 81 capable of spraying the cleaning liquid with a sufficient striking force to the component parts are used, and each of them is arranged around the oil tank 5. It can arrange | position so that a washing | cleaning liquid can be ejected toward the mounting part 53 direction of a bottom face from a part.

In addition, the inert oil F used in the oil immersion cleaning process of the second embodiment is not particularly limited as long as the reactivity with sodium is sufficiently low. For example, in the case of a sodium dispersion production facility as described in the first embodiment, the parts are used after the oil immersion cleaning by using the same inert oil as the insulating oil used for the dispersion medium of the sodium dispersion. It is not necessary to remove the inert oil used for the cleaning from the constituent parts, and the cleaning operation is simplified, and the possibility of mixing different types of inert oil into the sodium dispersion can be suppressed.
Further, as the cleaning liquid FL used for cleaning after the oil immersion cleaning process by the spray nozzle, the same inert oil as the inert oil used for the oil immersion cleaning, other inert oil, alcohol, or the inert oil A mixed liquid of alcohol and alcohol, water, or the like can be used.

Next, the metallic sodium adhering from the component A is stored in the oil tank 5 in a state where the component A and the inert oil F adhering to the metallic sodium are heated above the melting point of sodium. A method of cleaning the equipment using sodium by performing the oil immersion cleaning process to be removed will be described.
First, the component A to which metallic sodium is attached is separated from the facility using sodium and placed on the mounting portion 53 in the oil tank 5 so that the placed component A is completely immersed. The active oil F is introduced into the oil tank 5, and the inert oil F is heated by the heating wall 55 while the inert oil F is stirred by the stirring mechanism 6.
At this time, the temperature control mechanism 7 causes the temperature in the tank to be equal to or higher than the melting point of sodium, preferably 120 to 140 ° C., and causes the metallic sodium attached to the component to be in a molten state, thereby removing the metallic sodium from the component. .
At this time, if necessary, the flow state of the inert oil F around the component A can be promoted by the stirring mechanism 6 and the like, and the removal of metallic sodium from the component A can be promoted.

The metallic sodium removed from the component A in this manner is discharged from the oil discharge hole together with the inert oil F after the oil immersion cleaning step and removed from the system as shown in FIG.
Since metallic sodium is removed from the component A in the inert oil F in this way, the cleaning operation of the facility using sodium is made simpler and safer than the method using a conventional burner. Can do.
For example, even if a slight amount of metallic sodium remains in the component from which the metallic sodium attached by this oil immersion cleaning process has been removed, this residual component can be removed by continuously washing the component with alcohol or the like. A small amount of sodium can also be removed. As the cleaning after the oil immersion cleaning process, for example, as shown in FIG. 7, the cleaning liquid FL is sprayed from the spray nozzle 81 toward the mounting portion 53, and the component A mounted on the mounting portion 53 is used. The cleaning may be performed by spraying the cleaning liquid.

For example, while injecting alcohol from the injection nozzle 8 and washing the inert oil F adhering to the component by striking force with alcohol, the alcohol and the metal sodium slightly remaining in the component A It is possible to carry out an alcohol washing step in which the metal sodium remaining by the alcohol is reacted and the sodium metal is washed away.
As the alcohol used as the cleaning liquid in this alcohol cleaning step, isopropyl alcohol (hereinafter also referred to as “IPA”), which has a high detergency for many inert oils and has an excellent sodium cleaning effect, is suitable.
In this way, by performing the alcohol cleaning step of injecting alcohol in the oil tank 5 after oil immersion cleaning, the inert oil F adhering to the component A can be cleaned, and it can also adhere to the wall surface of the oil tank 5. Washing can be performed simultaneously when the inert oil F or the bottom of the oil tank is attached with sodium.
In other words, by using alcohol, particularly IPA, the cleaning of the inert oil F and sodium remaining in the component A and the oil tank 5 is efficiently performed, and the cleaning operation of the facility using sodium is simpler. Can be.

  In addition, if necessary, before carrying out this alcohol washing process, a mixture of alcohol and inert oil is sprayed onto the component parts and sodium remaining on the component parts or sodium adhering to the bottom of the oil tank After performing the mixed solution washing process that gently causes a reaction and partially removes it, it is possible to carry out the alcohol washing step as described above. Can be further enhanced.

In addition, if necessary, an inert oil heated to a melting point of sodium or higher before this alcohol washing step or mixed solution washing step is sprayed on this component part to further remove sodium remaining in the component part by striking force. It is also possible to carry out a warming oil injection process in which the sodium attached to the bottom of the oil tank is removed and discharged from the oil discharge hole.
In this way, the heated oil injection process is performed following the oil immersion cleaning process, the mixed liquid cleaning process is performed subsequent to the heated oil injection process, and the alcohol cleaning process is performed subsequent to the mixed liquid cleaning process. Or after the oil immersion cleaning step, the mixed solution cleaning step is performed, and the alcohol cleaning step is performed subsequently to the mixed solution cleaning step. It is possible to further improve the safety of the work by sequentially switching to the cleaning liquid having high reactivity with and performing cleaning in multiple stages.
Moreover, you may perform the washing | cleaning process by water or water vapor | steam after an alcohol washing | cleaning process and a liquid mixture washing | cleaning process. By washing with water or the like, oil and alcohol adhering to the components can be removed, so that contamination of impurities can be suppressed when returning to the facility using sodium.
Moreover, you may perform a drying process after a washing | cleaning process. By drying the component parts, alcohol and water do not remain in the cleaned component parts, so that it is possible to suppress an unnecessary reaction with sodium when the component parts are returned to the facility using sodium.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG.
In this embodiment, the component A to which sodium is attached is separated from the facility using sodium, and the component A to which sodium is attached is immersed in an inert oil F that has been heated to the melting point of sodium or higher in the oil tank 5. In the point which implements the oil immersion washing | cleaning process, it is the same as that of said 2nd embodiment.
In the second embodiment, the example in which the alcohol cleaning process or the mixed liquid cleaning process is performed in the oil tank 5 after the oil immersion cleaning process has been described. However, in the third embodiment, the oil immersion cleaning process is performed. Later, the component A from which the sodium adhering from the oil immersion cleaning process has been removed is taken out of the oil tank 5 and transferred to another location, and the water washing process of cleaning this component with water W is further performed. This is different from the second embodiment.

The equipment used for the oil immersion cleaning process of this embodiment is the same as that of said 2nd embodiment. In this embodiment, the water reaction tank 9 for making the component A and the water W after an oil immersion cleaning process contact is further provided.
The water reaction tank 9 has a water reaction tank body 91 formed in a size capable of accommodating the component A from which metallic sodium has been removed in the oil immersion cleaning process, and water is introduced into the water reaction tank body 91. A water introduction mechanism (not shown).

  In order to carry out the cleaning of the sodium using equipment with such equipment, first, the component A to which the metallic sodium is adhered is separated from the sodium using equipment and placed on the placing portion 53 in the oil tank 5, The inert oil F is introduced into the oil tank 5 so that the mounted component A is completely immersed, and the inert oil F is heated by the heating wall 55 while stirring the inert oil F by the stirring mechanism 6. It is the same as that of said 2nd embodiment until it heats and implements an oil immersion washing | cleaning process.

  Next, in the second embodiment, the case where the inert oil F containing metallic sodium removed from the component A after the oil immersion cleaning process is discharged from the oil discharge hole 52 is described as an example. The component A from which the metal sodium has been removed is removed while leaving the inert oil F in the oil tank 5 and the removed metal sodium in the oil tank 5, and transferred to the water reaction tank body 91 of the water reaction tank 9. Water W introduced by the water introduction mechanism is reacted with sodium remaining in the components after the oil immersion cleaning process.

At this time, for example, water W is introduced into the water reaction tank main body 91 in advance, and the component A is submerged in the water so that sodium remaining in the component A reacts with the water W. The sodium remaining in the component A can be washed with the water W.
Further, for example, the component A after the oil immersion cleaning process is accommodated in the water reaction tank main body 91 in a state where the water W is not introduced into the water reaction tank main body 91, and the water W is introduced after the component A is accommodated. A water washing step can also be performed.

  Further, if necessary, a water vapor treatment step for bringing the component A after the oil immersion washing step into contact with water vapor such as dry steam can be performed before the water washing step. By performing a steam treatment step before this water washing step, when sodium remains in the component parts, sodium and water vapor are brought into contact with each other to cause a slow reaction between sodium and water vapor, and the subsequent water washing step It is possible to reduce the reactivity in and improve the safety of the cleaning operation.

In this way, when the component from which sodium has been removed is taken out of the oil tank and transferred to another location to perform the water washing step after the oil immersion cleaning step, the water washing step after the oil immersion cleaning step is performed. Then, another component can be newly cleaned in the oil tank.
In addition, although the water washing process was demonstrated here as an example, it replaces with this water washing process, and when performing the alcohol washing process and mixed liquid washing process which were demonstrated in 2nd embodiment in a place different from an oil tank. In addition, the oil bath cleaning process can be performed several times using the oil tank continuously, and further cleaning processing after the oil immersion cleaning process can be performed, so that the cleaning efficiency of the sodium-using equipment is further improved. Can be.
Moreover, you may perform a drying process after the water washing process similarly to 2nd embodiment.
Moreover, since it is suppressed that the heated inert oil is discharged | emitted out of a system from an oil tank, the energy consumption for washing | cleaning of a sodium using equipment can also be reduced.

  In the above embodiment, the sodium dispersion production facility is mainly described as the sodium use facility. However, in the present invention, the sodium use facility is not limited to the sodium dispersion production facility. In the case of equipment, equipment using liquid sodium metal as a heat transfer medium, or equipment using other sodium, the scope of the present invention is also intended.

The flowchart which shows 1st embodiment. The fragmentary sectional view which shows the dispersion apparatus used for a sodium dispersion manufacturing equipment. The front view which shows the stator and rotor of the dispersion apparatus of FIG. The flowchart which shows another aspect of 1st embodiment. The apparatus sectional view showing the oil immersion washing process of a second embodiment. The apparatus sectional view showing the situation after the oil immersion washing process of the second embodiment. The apparatus sectional view showing the further washing process after the oil immersion washing process of the second embodiment. The apparatus sectional view showing the water washing process of a third embodiment.

Explanation of symbols

  1: sodium reservoir, 2: insulating oil reservoir, 3: sodium dispersion, 5: oil tank, 6: stirring mechanism, 7: temperature control mechanism, 8: injection nozzle, 9: water reaction tank, 11: sodium reservoir , 12: Pressurized nitrogen supply device (pressurizing mechanism), A: component, F: inert oil, FL: cleaning liquid, L1: sodium transport piping, Lb: bypass piping, W: water

Claims (2)

A sodium dispersion part in which metallic sodium in a liquid state is dispersed in the dispersion medium to form a sodium dispersion in which sodium is dispersed in the dispersion medium in which the inert oil is used, and a liquid state in the sodium dispersion part A sodium storage part in which metal sodium is stored in a liquid state to supply the metal sodium, and a sodium transport pipe part having a pipe for transporting the liquid metal sodium from the sodium storage part to the sodium dispersion part. A sodium dispersion for producing a sodium dispersion by supplying liquid sodium metal to the sodium dispersion part from the sodium storage part through a pipe of a sodium transport pipe part using a sodium dispersion production facility provided A manufacturing method comprising:
A dispersion medium storage section for storing the inert oil and having the sodium transport piping section provided between the sodium storage section and the sodium dispersion section respectively installed in a separate building is further installed in the separate building A dispersion medium transport pipe section provided between the dispersion medium storage section and the sodium dispersion section; and a bypass pipe section connecting the dispersion medium transport pipe section and the sodium transport pipe section. Using the sodium dispersion production facility, the inert oil is supplied from the dispersion medium reservoir to the sodium dispersion section through the dispersion medium transport pipe section, and from the sodium reservoir section to the sodium dispersion section through the sodium transport pipe section. After supplying sodium metal in a liquid state to produce one batch of sodium dispersion, By way of the bypass pipe portion is passed through an inert oil, which is heated to a temperature sodium above the melting point of the piping sodium conveying pipe portion after supplying metallic sodium of the liquid state of the sodium conveying pipe section An oil circulation washing process for removing metallic sodium adhering to the component parts is performed, and the inert oil after being used in the oil circulation washing process is used for producing a sodium dispersion of the next batch. Sodium dispersion manufacturing method. The sodium reservoir has a sodium reservoir for storing metallic sodium in a liquid state in the sodium reservoir, and further includes a pressurized nitrogen supply device for supplying pressurized nitrogen to the sodium reservoir, and the pressurization using the sodium dispersion manufacturing equipment The method for producing a sodium dispersion according to claim 1 , wherein the metallic sodium is pumped from the sodium reservoir to the sodium dispersion by a nitrogen supply device.

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