JP2007106649A - Method of manufacturing ammonium biuranate particle and manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for manufacturing ammonium biuranate particles which can freely control particle size and can steadily and efficiently manufacture high quality ammonium biuranate particles. <P>SOLUTION: In the method and apparatus for manufacturing ammonium biuranate particle, a raw liquid for manufacturing an ammonium biuranate particle containing uranyl nitrate and a thickener is dropped into an ammonium water solution to form ammonium biuranate particles, the diameter of the raw liquid droplets formed by dropping is measured with a sensor not in contact with the liquid droplets, and the manufacturing conditions are controlled based on the diameter of the measured liquid droplets. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for producing ammonium deuterated uranium particles, and more particularly, to the production of a fuel core for a high temperature gas reactor fuel that can freely control the particle size and has excellent quality. The present invention relates to a method and an apparatus for producing ammonium heavy uranate particles capable of efficiently producing stable ammonium heavy uranate particles.

  The core into which the fuel of the high-temperature gas reactor is charged is formed of graphite having a large heat capacity and excellent high-temperature soundness. In this high-temperature gas furnace, a gas such as helium gas that does not cause a chemical reaction even at high temperatures and has high safety is used as the cooling gas, so even if the outlet temperature is high, the cooling gas can be safely used. It can be taken out. Therefore, even if the temperature of the core rises to about 900 ° C., the cooling gas heated to a high temperature can be used safely in a wide range of fields such as power generation, hydrogen production equipment, and other chemical plants. Yes.

  Moreover, the fuel for a high temperature gas reactor to be charged into the high temperature gas reactor generally includes a fuel core and a coating layer that covers the periphery of the fuel core. The fuel core is, for example, fine particles having a diameter of about 350 to 650 μm formed by sintering uranium dioxide into a ceramic form.

The coating layer has a four-layer structure, and has a first layer, a second layer, a third layer, and a fourth layer from the fuel core surface side. The first layer is formed of low-density pyrolytic carbon having a density of about 1 g / cm ³ , functions as a gas reservoir for gaseous fission products (FP), and serves as a buffer for absorbing fuel nuclear swelling. It also has the function of The second layer is formed of high-density pyrolytic carbon having a density of about 1.8 g / cm ³ and has a function of holding a gaseous FP. The third layer is formed of silicon carbide (SiC) having a density of about 3.2 g / cm ³ , has a function of holding a solid FP, and is a main strength member of the coating layer. The fourth layer is formed of high-density pyrolytic carbon having a density of about 1.8 g / cm ³ and has a function of holding a gaseous FP and also a function of a protective layer of the third layer. . The diameter of the coated particles forming these coating layers is usually about 500 to 1000 μm.

  The fuel nuclei (coated fuel particles) covered with the four coating layers are dispersed in a graphite matrix and molded into a fixed fuel compact shape. The fuel compact is a cylinder made of graphite. A fixed quantity is accommodated in the container and plugged up and down to form a fuel rod. Ultimately, this fuel rod is inserted into a plurality of insertion holes of the hexagonal column type graphite block, and a core is formed by arranging a plurality of the hexagonal column type graphite blocks in a honeycomb shape and stacking a plurality of stages. The

  Such a HTGR fuel can generally be manufactured through the following steps. First, a uranium nitrate solution is prepared by dissolving uranium oxide powder in nitric acid. Next, if necessary, water and a thickener are added to the uranyl nitrate solution, and the mixture is stirred and mixed to prepare a stock solution for producing ammonium biuranate particles (hereinafter sometimes simply referred to as “stock solution”). Thickener is a substance that increases the viscosity of the stock solution and is added so that droplets of uranyl nitrate, which is a stock solution dropped into an aqueous ammonia solution described later, become true spheres by its surface tension during the fall. It is.

  Examples of the thickener include polyvinyl alcohol, a resin having a property of solidifying under alkaline conditions (for example, methylcellulose), polyethylene glycol, and metroses. The stock solution prepared in this manner is cooled to a predetermined temperature to obtain a drop stock solution whose viscosity is adjusted, and then ammonia is produced by vibrating the nozzle from a small-sized stock droplet lower nozzle of the stock droplet lowering device. It is dripped in the aqueous ammonia solution in the aqueous solution storage tank.

  The droplets dropped into the aqueous ammonia solution pass through the ammonia gas existing in the space until reaching the surface of the aqueous ammonia solution. Further, ammonia gas may be positively sprayed on the droplets. Since the droplet surface is gelled by this ammonia gas and a film is formed, the droplet particles on which the gel film is formed are prevented from being deformed by an impact when falling onto the surface of the aqueous ammonia solution. The aqueous ammonia solution in the ammonia aqueous solution storage tank is circulated from the lower side to the upper side of the aqueous ammonia solution storage tank so that the lower droplet particles are not deformed by the load of the droplet particles on the upper side. In this aqueous ammonia storage tank, uranyl nitrate reacts with ammonia to form ammonium heavy uranate particles.

  The ammonium heavy uranate particles formed in the ammonia aqueous solution storage tank are transferred to a post-treatment device that is connected to the ammonia aqueous solution storage tank. The transfer of the heavy ammonium uranate particles to the post-treatment device is normally performed by opening a valve of a pipe connecting the ammonia aqueous solution storage tank and the post-treatment device and dropping it together with the aqueous ammonia solution by its own weight. In this post-treatment device, while rotating the post-treatment tank, by heating, the uranyl nitrate and ammonia are completely reacted to the center of the particles to produce ammonium heavy uranate (ripening treatment), heavy uranic acid with hot water, etc. It is an apparatus that performs a process for cleaning ammonium particles (cleaning process) and a process for drying (drying process).

  Aged, washed and dried ammonium heavy uranate particles are roasted in air to form uranium trioxide particles. Further, the uranium trioxide particles are reduced and sintered to become high-density ceramic-like uranium dioxide particles. The uranium dioxide particles thus formed are classified and obtained as fuel core fine particles having a predetermined particle diameter.

  The fuel core particles obtained in this way are loaded onto a fluidized bed and coated by thermally decomposing the coating gas. For example, the first layer can be formed by pyrolyzing acetylene at about 1400 ° C., and the second and fourth layers can be formed by pyrolyzing propylene at about 1400 ° C. it can. For example, the third layer can be formed by thermally decomposing methyltrichlorosilane at about 1600 ° C. A normal fuel compact can be manufactured by press-molding or molding coated fuel particles into a hollow cylindrical shape or a medium-density cylindrical shape together with a graphite matrix material composed of graphite powder, a binder, and the like, followed by firing. (See Non-Patent Documents 1 and 2).

"Reactor Material Handbook" p221-p247, published October 31, 1977, published by Nikkan Kogyo Shimbun "Nuclear Power Handbook" p161-p169, issued on December 20, 1995, Ohm Corporation

  In such a HTGR fuel manufacturing method, the particle size of ammonium deuterated uranium particles formed by reacting uranyl nitrate and ammonia in an aqueous ammonia storage tank is conventionally obtained by dissolving uranium oxide in nitric acid. It was governed by the preparation process of the uranyl nitrate solution prepared in the above. In other words, a stock solution for producing ammonium heavy uranate particles adjusted to a certain temperature and viscosity by adding a thickener and water if necessary to a uranyl nitrate solution and stirring and mixing is based on the flow rate of the stock solution. The frequency of the nozzle below the original droplet was determined and dropped into the aqueous ammonia storage tank to form ammonium heavy uranate particles having a predetermined particle size.

  However, the temperature and viscosity of the stock solution change during liquid feeding or dripping due to some disturbance, and the particle size of ammonium deuterated uranate particles formed in the ammonia aqueous solution storage tank does not reach the desired particle size. When it arrived, there was a problem that the operation had to be interrupted immediately and the temperature, viscosity, flow rate and frequency of the nozzle below the original droplet had to be readjusted. For this reason, a situation in which the ammonium heavy uranate particles having excellent quality cannot be constantly produced is caused, and the production efficiency of the ammonium heavy uranate particles is reduced.

  The present invention eliminates such conventional problems, allows the particle size to be freely controlled, and makes it possible to stably and efficiently produce ammonium heavy uranate particles having excellent quality. It is an object of the present invention to provide a method and an apparatus for producing ammonium acid particles.

  In order to solve the above-mentioned problems, the present inventor has made various studies on means for controlling the production conditions, and as a result, the diameter of the stock solution dropped in the aqueous ammonia solution or the heavy uranium formed in the aqueous ammonia solution The inventors have found that the problem can be solved by measuring the particle diameter of ammonium acid particles and reflecting the measured diameter or the particle diameter in manufacturing conditions, and to complete the invention based on this finding. Arrived.

That is, the first means for solving the problems of the present invention is as follows:
(1) A method for producing ammonium heavy uranate particles in which a stock solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener is dropped into an aqueous ammonia solution to form ammonium heavy uranate particles, A weight of the droplet of the stock solution formed by dripping is measured by a sensor in a non-contact manner with the droplet, and a manufacturing condition is controlled based on the measured diameter of the droplet. This is a method for producing ammonium uranate particles.

The second means for solving the problems of the present invention is as follows:
(2) A method for producing ammonium heavy uranate particles in which a stock solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener is dropped into an aqueous ammonia solution to form ammonium heavy uranate particles, The particle size of the ammonium heavy uranate particles formed in the aqueous ammonia solution is measured by a sensor in a non-contact manner with the ammonium heavy uranate particles, and is manufactured based on the measured particle size of the ammonium heavy uranate particles. This is a method for producing ammonium biuranate particles characterized by controlling the conditions.

As a preferable aspect in the first means or the second means,
Production of measured droplet diameter data or particle size data of ammonium heavy uranate particles, and production of ammonium heavy uranate particles for controlling the production conditions based on the accumulated diameter data or particle size data A method can be mentioned.

The third means for solving the problems of the present invention is as follows:
(3) An original aqueous drop device having an original liquid drop nozzle for dropping an original solution for production of ammonium deuterated uranate particles containing uranyl nitrate and a thickener, and an aqueous ammonia solution storing an aqueous ammonia solution disposed below the original liquid drop device An apparatus for producing ammonium biuranium particles having a storage tank is provided with a sensor capable of measuring the diameter of the droplet of the original solution dropped from the nozzle below the original droplet without contact with the droplet. This is an apparatus for producing ammonium heavy uranate particles.

Further, a fourth means for solving the above-mentioned problems of the present invention is as follows:
(4) An ammonia aqueous solution storing an original droplet lower device having an original droplet lower nozzle for dropping an original solution for production of ammonium deuterated uranate particles containing uranyl nitrate and a thickener, and an aqueous ammonia solution disposed below the original droplet lower vessel. In a production apparatus for ammonium heavy uranate particles having a storage tank, the particle diameter of ammonium heavy uranate particles formed by reacting the dropped stock solution and the aqueous ammonia solution with the ammonium heavy uranate particles, An apparatus for producing ammonium heavy uranate particles, comprising a sensor capable of non-contact measurement.

As a preferable aspect in the third means or the fourth means,
The measured particle diameter data of the droplets or the particle diameter data of the heavy ammonium uranate particles is accumulated, and a weight having a control unit for controlling manufacturing conditions based on the accumulated diameter data or particle diameter data. An apparatus for producing ammonium uranate particles can be mentioned.

  In the present invention, the diameter of a stock solution dropped in an aqueous ammonia solution or the particle diameter of ammonium biuranate particles formed in the aqueous ammonia solution is measured by a sensor, and the measured diameter or the particle diameter is measured. It is a production method and production apparatus of ammonium heavy uranate particles that control the production conditions by reflecting the production conditions. According to this production method and production apparatus, the particle size can be freely controlled, and the quality is excellent. There is an effect that ammonium heavy uranate particles having the above can be stably and efficiently produced. For this reason, the place which contributes to the manufacturing field of the fuel for HTGR is very large.

  (1) According to the method for producing ammonium heavy uranate particles of the present invention, a raw solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener is dropped into an aqueous ammonia solution to form ammonium heavy uranate particles. A method for producing ammonium biuranium particles, wherein the droplet diameter of the stock solution formed by dripping is measured by a sensor in a non-contact manner with the droplet, and the measured droplet diameter is obtained. Based on this, the manufacturing conditions are controlled.

  In the method for producing ammonium heavy uranate particles of the present invention, first, uranium oxide is dissolved in nitric acid to prepare a uranyl nitrate solution. The preparation conditions at this time are not particularly limited, but usually, for example, 0.8 to 5.2 kg of uranium oxide and 1 to 5 L of nitric acid are stirred and mixed at 10 to 100 ° C. for 10 to 200 minutes. It is prepared by.

  Next, the uranyl nitrate solution prepared as described above is mixed with a thickener and, if necessary, water to prepare a stock solution for producing ammonium biuranate particles. Examples of the thickener include polyvinyl alcohol, a resin having a property of solidifying under alkaline conditions (for example, methylcellulose), polyethylene glycol, and metroses. Two or more of these thickeners may be used in combination. Although there is no restriction | limiting in particular also in the said mixing process conditions, Usually, 3-15L uranyl nitrate solution and 2-13 kg thickener are stirred and mixed at 5-30 degreeC for 20-180 minutes, for example.

  The stock solution prepared in this manner is cooled to a predetermined temperature to obtain a drop stock solution whose viscosity is adjusted, and then ammonia is produced by vibrating the nozzle from a small-sized stock droplet lower nozzle of the stock droplet lowering device. Dropped into an aqueous solution. Although there is no restriction | limiting in particular in the density | concentration of aqueous ammonia solution at this time, Usually, it is 5-40 mass%. The droplets dropped into the aqueous ammonia solution pass through the ammonia gas existing in the space until reaching the surface of the aqueous ammonia solution. Further, ammonia gas may be positively sprayed on the droplets. The surface of the droplet is gelled by the ammonia gas to form a droplet having a film formed thereon. Uranyl nitrate in the stock solution dropped into the aqueous ammonia solution reacts with ammonia to form ammonium deuterated uranate particles.

  In the method for producing ammonium heavy uranate particles according to the present invention, the undiluted liquid droplets formed in the course of dropping the undiluted liquid solution into the aqueous ammonia solution from the nozzles under the original liquid droplets (droplets formed by gelation to form a film) Is measured by a sensor without contact with the droplet.

  Examples of the sensor include a sensor that combines a charge coupled device (CCD) and a light source such as strobe light, light emitting diode light, or laser light, a sensor that uses transmitted laser light (laser scattering sensor), laser diffraction, and the like. Sensors utilizing the phenomenon (laser reflection type sensors) can be mentioned. Among these sensors, a sensor in which a CCD and a light emitting diode are combined is preferable. A sensor combining this CCD and a light emitting diode (hereinafter sometimes referred to as “LED-CCD sensor”) is obtained by converting light from the light emitting diode into parallel light using a diffraction slit and projecting it onto particles. This is a sensor that can detect the length of the projected image by a CCD element.

  In the method for producing ammonium heavy uranate particles according to the present invention, the production conditions are controlled based on the diameter of the droplets thus measured. Examples of the production conditions include the temperature, viscosity, flow rate, and frequency of the nozzle under the original droplet, and the frequency of the stock solution and the frequency of the nozzle under the original droplet are particularly important.

  (2) Further, the method for producing ammonium heavy uranate particles according to the present invention comprises adding a stock solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener into an aqueous ammonia solution to drop the ammonium heavy uranate particles. A method for producing ammonium heavy uranate particles, wherein the particle size of the ammonium heavy uranate particles formed in an aqueous ammonia solution is measured in a non-contact manner with the ammonium heavy uranate particles using a sensor. The manufacturing conditions are controlled based on the particle size of the ammonium biuranate particles.

  The step of preparing the stock solution for producing the ammonium heavy uranate particles, the step of dropping the stock solution into an aqueous ammonia solution to form the ammonium heavy uranate particles, and the like are the method for producing ammonium heavy uranate particles according to (1) above. There is no change.

  In the method for producing ammonium heavy uranate particles according to the present invention, the particle size of the ammonium heavy uranate particles formed in the aqueous ammonia solution is measured by a sensor in a non-contact manner with the ammonium heavy uranate particles.

  Examples of the sensor include a sensor using a dynamic light scattering phenomenon (hereinafter sometimes referred to as “dynamic light scattering sensor”), a sensor using a laser and a CCD, a CCD camera, and the like. it can. When a CCD is used, an image picked up by the CCD is processed by an image processing apparatus and the particle size is measured. Among these sensors, a dynamic light scattering sensor is preferable. The dynamic light scattering sensor is a sensor that can determine the particle size of the ammonium heavy uranate particles from the light scattering intensity due to the Brownian motion of the ammonium heavy uranate particles in the aqueous ammonia solution.

  In the method for producing ammonium heavy uranate particles of the present invention, the production conditions are controlled based on the particle size of the ammonium heavy uranate particles thus measured. Examples of the production conditions include the same conditions as in the method (1) for producing ammonium biuranate particles.

  In the method for producing ammonium heavy uranate particles according to (1), it is preferable to accumulate the measured droplet diameter data and control the production conditions based on the accumulated diameter data.

  At this time, for example, when an LED-CCD sensor is used as the sensor, first, the diameter of the droplet of the stock solution formed while the stock solution is dropped into the aqueous ammonia solution from the nozzle under the stock droplet is a light emitting diode. The projected image of the droplet obtained by the light emitted from the image is processed by image processing of the image obtained by capturing the image with the CCD, and the measured diameter data is stored and displayed in the diameter control unit.

  Next, the diameter data information is separately analyzed by a prepared control system. From the analysis result, it has been found that the predetermined manufacturing conditions must be changed without satisfying the predetermined diameter. In order to obtain an appropriate diameter, for example, a command is issued to change the flow rate of the stock solution and the frequency of the nozzle below the stock droplet. The diameter measurement, diameter data accumulation and display, diameter data information analysis, and manufacturing condition change commands can be repeated continuously to obtain an appropriate diameter.

  Further, in the method for producing ammonium heavy uranate particles according to (2), the measured particle size data of the ammonium heavy uranate particles is accumulated, and the production conditions are controlled based on the accumulated particle size data. It is preferable to do.

  At this time, for example, when a dynamic light scattering type sensor is used as the sensor, first, the light scattering intensity due to the Brownian motion of the ammonium deuterated uranate particles in the aqueous ammonia solution is measured, and the measured particle size data Are stored in the particle size control unit and displayed.

  Next, the particle size data information is separately analyzed by a prepared control system, and from this analysis result, the predetermined particle size may not be satisfied and the initially determined manufacturing conditions may have to be changed. When it becomes clear, for example, a command is issued to change the flow rate of the stock solution and the frequency of the nozzle below the stock droplet so as to obtain an appropriate particle size. The measurement of particle size, accumulation and display of particle size data, analysis of particle size data information, and a change command for manufacturing conditions can be repeated repeatedly to obtain an appropriate particle size. In this way, the particle size of the ammonium biuranate particles can be determined.

  (3) An apparatus for producing ammonium heavy uranate particles according to the present invention includes an original droplet lowering device having an original droplet lowering nozzle for dropping a raw solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener, and the original droplet lowering device. In the apparatus for producing ammonium deuterated uranium particles having an ammonia aqueous solution storage tank for storing an aqueous ammonia solution disposed below, the diameter of the droplet of the original solution dropped from the nozzle below the original droplet is set as the droplet. It is a device comprising a sensor that can measure without contact.

  The manufacturing apparatus of the said ammonium heavy uranate particle is demonstrated based on drawing. FIG. 1 is a diagram showing an example of an apparatus for producing ammonium heavy uranate particles according to the present invention. An apparatus 1 for producing ammonium heavy uranate particles according to the present invention includes an original liquid drop device 3 having an original liquid drop nozzle 2 for dropping a raw solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener, and the original liquid drop device. 3, an ammonia aqueous solution storage tank 5 for storing an ammonia aqueous solution 4 disposed below 3 is provided.

  In the ammonium heavy uranate particle producing apparatus 1, ammonia gas 6 is present in the upper space of the ammonia aqueous solution storage tank 5, and sensors 7 are disposed on both outer sides of the ammonia aqueous solution storage tank 5 where the ammonia gas 6 is present. -1 and 7-2 are equipped. Examples of the sensor 7 include an LED-CCD sensor, a dynamic light scattering sensor, a laser diffraction sensor, and the like. Among these sensors, an LED-CCD sensor is preferable.

  In order to produce ammonium heavy uranate particles using the production apparatus 1 for ammonium heavy uranate particles, first, a stock solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener is prepared. The preparation of the stock solution is as described in the method for producing ammonium biuranate particles (1). Next, the prepared stock solution is supplied to the stock droplet lowering device 3 through the stock solution flow rate adjusting valve 9 by the stock solution feed pump 8.

  The stock solution supplied to the original liquid drop lower device 3 passes through the ammonia gas 6 from the vibrating original liquid drop lower nozzle 2 and is dropped into the ammonia aqueous solution storage tank 5 as a droplet 10. The uranyl nitrate in the stock solution dropped into the ammonia aqueous solution storage tank 5 reacts with ammonia to form ammonium heavy uranate particles 11.

  In the ammonium heavy uranate particle production apparatus 1, the stock solution droplet 10 (gelled by the ammonia gas 6 and coated with the stock solution) is formed while the stock solution is dropped into the ammonia aqueous solution storage tank 5 from the stock droplet lower nozzle 2. The diameter of the droplet in which the droplet is formed is measured without contact with the droplet 10 by the sensors 7-1 and 7-2. In the case of using a laser diffraction sensor as the sensor 7, the sensor 7 has the sensor 7-1 as a light emitting unit and the sensor 7-2 as a light receiving unit. This is as described in the method for producing ammonium uranate particles. Reference numeral 12 denotes a diameter control unit, and 13 denotes a dropping nozzle control unit.

  (4) In addition, an apparatus for producing ammonium heavy uranate particles according to the present invention includes an original droplet lowering device having a dropping nozzle for dropping an undiluted solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener, and Heavy uranic acid formed by reacting the dripped stock solution with the aqueous ammonia solution in an apparatus for producing ammonium heavy uranate particles having an aqueous ammonia storage tank for storing an aqueous ammonia solution disposed below the vessel An apparatus comprising a sensor capable of measuring the particle size of ammonium particles in a non-contact manner with the ammonium deuterated uranate particles.

  The manufacturing apparatus of the said ammonium heavy uranate particle is demonstrated based on drawing. FIG. 2 is a diagram showing an example of an apparatus for producing ammonium heavy uranate particles according to the present invention. The configuration of the production apparatus for ammonium heavy uranate particles of the present invention is substantially the same as that of the production apparatus for ammonium heavy uranate particles (3). However, the object of the measurement is the particle diameter of the ammonium heavy uranate particles 11 formed in the ammonia aqueous solution storage tank 5, and the sensor that is preferably used is different in that a dynamic light scattering sensor can be mentioned. To do. Further, the sensor 7 is different in that the sensor 7 is provided on both outer sides of a portion of the ammonia aqueous solution storage tank 5 where the ammonia aqueous solution 4 is stored and a particle size control unit 15 is provided.

  The (3) ammonium deuterated uranium particle production apparatus has a control unit for accumulating the measured droplet diameter data and controlling the production conditions based on the accumulated diameter data. It is preferable.

The control of the manufacturing conditions will be described with reference to FIG.
For example, when an LED-CCD sensor is used as the sensor 7, first, the diameter of the droplet 10 of the stock solution formed while the stock solution is dropped into the ammonia aqueous solution 4 from the nozzle 2 below the stock droplet is as follows. The projected image of the droplet obtained by the light emitted from the light-emitting diode is measured by image processing of the image obtained by imaging with the CCD, and the measured diameter data is stored in the diameter control unit 12 and displayed. To do.

  Next, the diameter data information is analyzed by a separately prepared control system (not shown), and from this analysis result, the predetermined condition is not satisfied and the initially determined manufacturing conditions are changed. When it has been found that, for example, an instruction to change the flow rate of the stock solution and the vibration frequency of the nozzle 2 under the original droplets is given, the raw solution feed pump 8 and the nozzle unit 13 under the original droplets are controlled so as to obtain an appropriate diameter. To be emitted.

  The control system is a system formed by a device for receiving a signal from an LED-CCD sensor, software for processing and analyzing the signal, and a computer environment for operating the processing and analysis.

  The diameter control unit 12 collects the diameter measured by the LED-CCD sensor in real time and analyzes the software based on a preset value to determine how far the current state deviates from the set value. It is a system that expresses numerical values and simultaneously reflects the numerical values on operating parameters.

  The flow rate change command of the stock solution is issued from the diameter control unit 12 so as to correct the deviation from the set value each time, for example. In response to this, an operation control unit (not shown) of the stock solution feed pump 8 finely adjusts the discharge amount of the stock solution feed pump 8 to change the flow rate of the stock solution.

  The original droplet lower nozzle control unit 13 includes an external input terminal, and controls the frequency, vibration width, and waveform of the original droplet lower nozzle 2 based on the operation parameters processed and determined by the diameter control unit 12. And a control unit that performs operation.

  The diameter measurement, diameter data accumulation and display, diameter data information analysis, and manufacturing condition change commands can be repeated continuously to obtain an appropriate diameter.

  In the production apparatus for ammonium heavy uranate particles of (4), the measured particle size data of the ammonium heavy uranate particles is accumulated, and the production conditions are controlled based on the accumulated particle size data. It is preferable to have a control unit.

The control of the manufacturing conditions will be described with reference to FIG.
For example, when a dynamic light scattering sensor is used as the sensor 7, first, the particle size of the ammonium heavy uranate particles 11 formed in the ammonia aqueous solution storage tank 5 is measured by the dynamic light scattering sensor, The measured particle size data is stored in the particle size control unit 15 and displayed.

  Next, the particle size data information is analyzed by a separately prepared control system (not shown). From this analysis result, the predetermined particle size is not satisfied, and the manufacturing conditions that were initially determined are determined. When it is found that the change must be made, for example, a command to change the flow rate of the stock solution and the vibration frequency of the nozzle under the original droplet is used to control the stock solution feeding pump 8 and the nozzle under the original droplet so as to obtain an appropriate particle size. Emitted to part 13.

  The particle size control unit 15, the control system, the flow rate of the stock solution is changed, and the original droplet lower nozzle control unit 13 is the same as described above, and the measurement of the particle size, accumulation and display of particle size data, Similarly, the analysis of the particle size data information and the change command of the manufacturing conditions can be repeated so that an appropriate particle size can be obtained.

  In the method and apparatus for producing ammonium heavy uranate particles according to the present invention, it is preferable to use a plurality of nozzles under the original droplets in order to further improve the production efficiency. FIG. 3 shows an apparatus (part) for producing ammonium heavy uranate particles having a plurality of nozzles under the original droplets.

  FIG. 3 shows a case where the diameter of the droplet 10 of the stock solution formed while the stock solution is dropped into the ammonia aqueous solution 4 from the nozzle 2 below the stock droplet is measured by a laser diffraction sensor. 3 represents an original droplet lowering device, 7-1 represents a light emitting part of the laser diffraction type sensor, 7-2 represents a light receiving part of the laser diffraction type sensor, and 9 represents a stock solution flow rate adjusting valve.

  The measurement of the diameter of the droplet 10, the display when the diameter data is accumulated, the control of the flow rate of the stock solution and the frequency of the nozzle below the stock droplet are the same as described above. Also, in the case where ammonium deuterated uranate particles are formed in an aqueous ammonia solution and the particle size of the formed ammonium deuterated uranate particles is measured, a plurality of dropping nozzles can be used. The apparatus according to the manufacturing apparatus shown to can be used.

  The ammonium heavy uranate particles thus produced are then subjected to aging treatment, washing treatment and drying treatment, followed by roasting, reduction and sintering, whereby high-density ceramic-like uranium dioxide particles are obtained. It becomes. The uranium dioxide particles are classified and obtained as fuel core fine particles having a predetermined particle diameter.

  According to the method and apparatus for producing ammonium heavy uranate particles of the present invention, the diameter of the stock solution dropped into the aqueous ammonia solution or the particle diameter of the ammonium heavy uranate particles formed in the aqueous ammonia solution is measured by a sensor. A method and an apparatus for producing ammonium deuterated uranium particles capable of controlling the production conditions by measuring and reflecting the measured diameter or the particle diameter in the production conditions are provided, and the particle diameter can be freely controlled. Therefore, it is possible to stably and efficiently produce ammonium biuranate particles having excellent quality. Further, by using a plurality of dropping nozzles, ammonium heavy uranate particles can be more efficiently produced.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the examples.

(Example)
The ammonium heavy uranate particle | grains were manufactured using the manufacturing apparatus 1 of the ammonium heavy uranate particle | grains shown in FIG.
First, a uranyl nitrate solution (2.4 mol-U / L) was prepared in a dissolution tank (not shown). A thickener was added to this uranyl nitrate solution and stirred to prepare a stock solution for production of ammonium biuranate particles. The viscosity of this stock solution was 70 × 10 ⁻³ Pa · s.

Subsequently, the prepared stock solution was supplied to the stock droplet lowering device 3 by the stock solution feed pump 8 through the stock solution flow rate adjusting valve 9 at a stock solution flow rate of 300 ± 80 cm ³ / min. The ammonia gas 6 was passed through the original droplet lower nozzle 2 oscillated at a vibration frequency of 40 to 60 Hz and dropped into the aqueous ammonia solution storage tank 5 as the droplet 10 from the original solution supplied to the original droplet lowering device 3.

  At this time, the diameter of the droplet 10 was measured by the laser diffraction sensor 7 (light emitting unit 7-1 and light receiving unit 7-2), and the measured diameter data was stored in the diameter control unit 12 and displayed. . The droplet 10 had a mean diameter of 25 μm. Next, as a result of analyzing the diameter data information stored and displayed in the diameter control unit 12 by the control system, it is recognized that the diameter can not produce ammonium deuterated uranate particles having a standard particle diameter, A command to change the flow rate of the stock solution and the vibration frequency of the stock droplet lower nozzle 2 was issued to the stock solution feed pump 8 and the stock droplet lowering device 3.

According to the command, the stock solution flow rate was changed to 200 ± 80 cm ³ / min, the frequency of the original droplet lower nozzle 2 was changed to 50 to 90 Hz, and subsequently, the same operation was performed. As a result, the average diameter of the droplets 10 was 2 μm. As a result of the above analysis, it is recognized that ammonium heavy uranate particles having a standard particle diameter can be produced as a result of the analysis, and the particles are directly dropped into the aqueous ammonia storage tank 5 to form ammonium heavy uranate particles 11. did.

It is a figure which shows an example of the manufacturing apparatus of the ammonium heavy uranate particle | grains of this invention. It is a figure which shows another example of the manufacturing apparatus of the ammonium heavy uranate particle | grains of this invention. It is a figure which shows an example of the manufacturing apparatus (part) of the ammonium heavy uranate particle | grains of this invention which has a some dripping nozzle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus of ammonium biuranium particle 2 Original droplet lower nozzle 3 Original droplet lower device 4 Ammonia aqueous solution 5 Ammonia aqueous solution storage tank 6 Ammonia gas 7 Sensor 7-1 Sensor light emission part 7-2 Sensor light receiving part 8 Stock solution feed pump 9 Stock solution Flow control valve 10 Stock solution droplet 11 Heavy ammonium uranate particles 12 Diameter control unit 13 Original droplet lower nozzle control unit 14 Production apparatus for heavy ammonium uranate particles 15 Particle size control unit

Claims (6)

  A method for producing ammonium heavy uranate particles, in which a stock solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener is dropped into an aqueous ammonia solution to form ammonium heavy uranate particles. The diameter of the droplet of the stock solution to be formed is measured by a sensor in a non-contact manner with the droplet, and the manufacturing conditions are controlled based on the measured diameter of the droplet. Particle production method.   A method for producing ammonium heavy uranate particles, in which a stock solution for producing ammonium heavy uranate particles containing uranyl nitrate and a thickener is dropped into an aqueous ammonia solution to form ammonium heavy uranate particles, the aqueous solution containing ammonia in aqueous ammonia The particle size of the ammonium heavy uranate particles formed in the above is measured by a sensor in a non-contact manner with the ammonium heavy uranate particles, and the manufacturing conditions are controlled based on the measured particle size of the ammonium heavy uranate particles. A method for producing ammonium heavy uranate particles.   The measured droplet diameter data or particle size data of the ammonium deuterated uranate particles is accumulated, and the production conditions are controlled based on the accumulated diameter data or particle size data. Method for producing ammonium biuranate particles.   An original droplet lowering device having a dropping nozzle for dropping an undiluted solution for production of ammonium biuranate particles containing uranyl nitrate and a thickener, and an aqueous ammonia solution storage tank for storing an aqueous ammonia solution disposed below the original droplet lowering device The apparatus for producing ammonium deuterated uranium particles comprises a sensor capable of measuring the diameter of the droplet of the stock solution dropped from the dropping nozzle in a non-contact manner with the droplet. Production equipment for ammonium deuterated uranate particles.   An original droplet lowering device having a dropping nozzle for dropping a raw solution for producing ammonium biuranium particles containing uranyl nitrate and a thickener, and an aqueous ammonia solution storage tank for storing an aqueous ammonia solution disposed below the original droplet lowering device The particle size of ammonium heavy uranate particles formed by reacting the dropped stock solution with the aqueous ammonia solution was measured in a non-contact manner with the ammonium heavy uranate particles. An apparatus for producing ammonium heavy uranate particles, characterized by comprising a sensor capable of performing the same.   A controller for accumulating measured droplet diameter data or particle diameter data of the ammonium deuterated uranium particles and controlling manufacturing conditions based on the accumulated diameter data or particle diameter data. Item 6. The apparatus for producing ammonium biuranium particle according to Item 4 or 5.

Images