Thorium target dissolving device and system and working method

Abstract

The thorium target dissolving device comprises a heating element, a dissolving tank is arranged above the heating element, the dissolving tank comprises a tank body with an opening in the top, the top end of the tank body is detachably connected with a top cover, a nitric acid solution feeding pipe and a hydrofluoric acid catalyst feeding pipe are arranged on the top cover, and a discharging pipe is arranged on the top cover. An exhaust pipe and a bubbling pipe are further arranged on the top cover, the bubbling pipe is connected with a gas supply mechanism through a gas pipeline so as to bubble the dissolving solution in the tank body, the exhaust pipe is connected with a condensation backflow device, and the dissolving device fills the blank of the thorium target dissolving technology in the hot chamber.

Description

Technical Field

[0001] The invention relates to the technical field of thorium target dissolving technology, and in particular to a thorium target dissolving device, system and working method. Background Art

[0002] The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Actinium-225 is the radionuclide with the best application prospects in α-targeted radiotherapy for malignant tumors. It has unique advantages in the treatment of micro-tumors, hematological tumors and scattered tumors, and has shown good therapeutic effects in preclinical trials and clinical studies of various tumors. Proton accelerator irradiation thorium target production 225 Ac is a method suitable for large-scale production. The accelerator irradiates the thorium target, the raw materials are abundant, the target preparation conditions are mild, and the target can be made of natural thorium. Then, the irradiated metal thorium target is cooled, the target is dissolved, and a large amount of thorium is removed. 225 Ac separation and purification processes are carried out to obtain actinium-225 with a radioactive nuclear purity of not less than 99%.

[0004] After the irradiated thorium target is cooled in the target disassembly hot chamber, the target is disassembled and transferred to the thorium target dissolving hot chamber for target dissolution. When the thorium target is dissolved, it is necessary to put the thorium target into a dissolution container, then introduce nitric acid solution and hydrofluoric acid, and then stir to dissolve. The current dissolution stirring device generally uses a stirring shaft and stirring blades connected to a motor for stirring, but the above-mentioned dissolution stirring device is not suitable for the dissolution of the thorium target in the hot chamber. On the one hand, nitric acid and hydrofluoric acid will corrode the stirring shaft and stirring blades, and the material requirements for the stirring mechanism are high, which increases the cost of the device. The current magnetic stirrer cannot be used for metal dissolution containers, but can only be used for glass containers. However, when the glass container is used in the hot chamber, the manipulator is prone to collision damage to it. Therefore, the current dissolution stirring device is not suitable for the dissolution of the thorium target in the hot chamber. Therefore, it is urgent to design a thorium target dissolution device for the hot chamber to meet the dissolution requirements of the thorium target. Summary of the invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide a thorium target dissolution device, system and working method, which can ensure the stirring of the dissolving liquid during the dissolution process and accelerate the dissolution rate of the thorium target.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] In the first aspect, an embodiment of the present invention provides a thorium target dissolving device, comprising a heating element, a dissolving tank is arranged above the heating element, the dissolving tank comprises a tank body with an open top, a top cover is detachably connected to the top of the tank body, a nitric acid solution feed pipe and a hydrofluoric acid catalyst feed pipe are arranged on the top cover, a discharge pipe is arranged on the top cover, an exhaust pipe and a bubbling pipe are also arranged on the top cover, the bubbling pipe is connected to the gas supply mechanism through a gas pipeline to bubble the dissolved liquid in the tank body, and the exhaust pipe is connected to the condensation reflux device.

[0008] Optionally, a first fixing plate is provided at the bottom edge of the top cover, and a second fixing plate matching the first fixing plate is provided on the top of the tank body. After the first fixing plate and the second fixing plate are fitted together, they are detachably fixedly connected by a plurality of threaded fasteners.

[0009] Optionally, a sealing ring is provided between the first fixing plate and the second fixing plate.

[0010] Optionally, the heating element is an electric heating sleeve.

[0011] Optionally, the top cover is provided with a temperature detection element.

[0012] Optionally, the dissolution tank is made of titanium 35 alloy.

[0013] In the second aspect, an embodiment of the present invention provides a thorium target dissolution system, comprising the thorium target dissolution device described in the first aspect, and also comprising a shearing machine, a first manipulator is provided on one side of the shearing machine to transfer the thorium target sent into the hot chamber to the shearing machine, a collecting element is provided below the drop port of the shearing machine, and a second manipulator is provided between the collecting element and the thorium target dissolution device to place the sheared thorium target block into a dissolution tank.

[0014] In a third aspect, an embodiment of the present invention provides a working method of the thorium target dissolution system according to the second aspect:

[0015] The first manipulator puts the thorium target sent into the dissolution hot chamber into the shearing machine, and the shearing machine shears the thorium target, and the sheared thorium target block falls into the collecting element;

[0016] The second manipulator puts the thorium target block into the dissolving tank, and adds the nitric acid solution and the hydrofluoric acid catalyst into the dissolving tank through the nitric acid solution feeding pipe and the hydrofluoric acid catalyst feeding pipe respectively;

[0017] The heating element and the gas supply mechanism are started, the heating element heats the dissolved liquid to a constant set temperature, and the gas supply mechanism bubbles the dissolved liquid through the bubbling tube until the dissolution reaction is completed.

[0018] Optional, constant set temperature of 100-120°C.

[0019] Optionally, the nitric acid solution is a 10-12M nitric acid solution, and the hydrofluoric acid catalyst is a 0.1M-0.2M hydrofluoric acid solution.

[0020] The beneficial effects of the present invention are as follows:

[0021] 1. In the thorium target dissolving device of the present invention, the top cover of the dissolving tank is connected with a bubbling tube, which is connected to a gas supply mechanism. During the dissolving process, gas can be introduced into the dissolved liquid to form bubbles, so as to stir the dissolved liquid and accelerate the dissolution of the thorium target. Only one bubbling tube is required, and the manufacturing cost is low. At the same time, the dissolving tank can be made of corrosion-resistant metal material, which is convenient for cooperation with a manipulator in a hot chamber, so that the target dissolving device is suitable for the dissolution of thorium targets in a hot chamber, filling the technical gap in this aspect.

[0022] 2. The thorium target dissolving device of the present invention shears the thorium target by a shearing machine and then puts it into a dissolving tank for dissolution, which further accelerates the dissolution rate of the thorium target. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0024] Figure 1 It is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0025] Among them, 1. nitric acid solution feed pipe, 2. temperature detection element, 3. discharge pipe, 4. exhaust pipe, 5. bubbling tube, 6. hydrofluoric acid catalyst feed pipe, 7. first fixed plate, 8. electric heating jacket, 9. dissolution tank, 10. handle. DETAILED DESCRIPTION

[0026] Example 1

[0027] The present embodiment provides a thorium target dissolving device, including a heating element, a dissolving tank 9 is arranged above the heating element, the heating element is used to heat the dissolving liquid in the dissolving tank 9 at a constant temperature, the dissolving tank 9 includes a tank body, the tank body is placed on the heating element, the top of the tank body is open, the top open end of the tank body is detachably connected to a top cover, and the top cover seals the top open end of the tank body. A nitric acid solution feed pipe 1 and a hydrofluoric acid catalyst feed pipe 6 are arranged on the top cover, and a discharge pipe 3 is also arranged on the top cover.

[0028] The nitric acid solution feed pipe 1 is connected to the nitric acid solution delivery pipe at the top of the dissolution hot chamber through a corrosion-resistant flexible pipe, and the nitric acid solution delivery pipe is connected to the nitric acid solution tank through a pipeline and a pump. The hydrofluoric acid catalyst feed pipe 6 is connected to the hydrofluoric acid delivery pipe at the top of the dissolution hot chamber through a corrosion-resistant flexible pipe, and the hydrofluoric acid delivery pipe is connected to the hydrofluoric acid tank through a pipeline and a pump.

[0029] The top cover is also provided with a discharge pipe 3, which extends to the bottom of the tank body. The discharge pipe 3 is connected to the aggregate container through a corrosion-resistant flexible pipe. The aggregate container is connected to a negative pressure device. The negative pressure device can evacuate the aggregate container, so that the dissolved solution in the dissolution tank is drawn into the aggregate container under the action of negative pressure. The aggregate container is used to collect the dissolved material so as to facilitate entering the next process.

[0030] The corrosion-resistant flexible pipe may be an existing corrosion-resistant flexible pipe, which will not be described in detail here.

[0031] The top cover is also provided with a bubbling tube 5, which extends into the bottom of the internal space of the dissolving tank 9. The bubbling tube 5 is connected to a gas supply mechanism, which can fill the dissolved liquid in the dissolving tank 9 with gas through the bubbling tube 5 to form bubbles and accelerate the dissolution of the thorium target.

[0032] Preferably, the gas supply mechanism uses an air compressor located outside the dissolution hot chamber, the air compressor is connected to an air path, the air path extends into the hot chamber and is connected to a bubbling tube, and preferably, the air path uses a corrosion-resistant flexible tube.

[0033] The bubbling tube 5 and the discharge tube 3 are both provided with valves. Preferably, the valves are electrically controlled valves connected to a control system and can receive instructions from the control system to work.

[0034] The top cover is also provided with an exhaust pipe 4, which is connected to the condensation reflux device and is used to condense the evaporated solution and then send it back to the waste liquid bottle. The condensation reflux device includes a metal condenser, the inlet end of the condenser is connected to the exhaust pipe 4, the condenser extends downward to the waste liquid bottle, and the outer periphery of the condenser is sheathed with a cooling pipe, which is provided with an inlet and an outlet, and the inlet and the outlet are connected to the hot chamber water source through a pipeline, wherein a cooling circulation pump is provided on the pipeline between the inlet and the hot chamber water source.

[0035] The waste liquid bottle collects the condensed dissolved liquid, and after regular storage, it is transported to the waste liquid evaporation room for concentration treatment.

[0036] The top cover is also provided with a temperature detection element 2 for detecting the temperature in the dissolving tank. The temperature detection element is connected to the control system and can transmit the detected information to the control system. The control system is connected to the heating element so that the heating element can maintain constant temperature heating.

[0037] Preferably, the temperature detection element can be a temperature sensor.

[0038] In this embodiment, the heating element is an electric heating sleeve 8, which can be made of existing equipment and will not be described in detail here.

[0039] In the present embodiment, in order to facilitate the addition of the thorium target into the dissolving tank 9 in the hot chamber, the top cover is detachably connected to the top of the tank body. Specifically, a first fixing plate 7 is provided at the outer edge of the bottom of the top cover, and correspondingly, a second fixing plate matching the first fixing plate is provided at the outer edge of the top of the tank body. The first fixing plate and the second fixing plate are detachably fixedly connected by a plurality of threaded fasteners. Preferably, the threaded fasteners can be bolts or nuts.

[0040] A sealing ring is provided between the first fixing plate 7 and the second fixing plate to seal the gap between the top cover and the tank body.

[0041] The dissolving tank 9 is made of titanium 35 material, and the nitric acid solution and hydrofluoric acid will not cause corrosion to it, and the service life is long.

[0042] Furthermore, a sampling tube is provided at the bottom of the dissolving tank, and the sampling tube is connected to the sampling interface of the hot chamber through a sampling pipeline. The staff can sample the solution in the dissolving tank through the sampling interface and a manual negative pressure liquid sampler.

[0043] Furthermore, a handle 10 is provided on the top cover to facilitate grabbing the top cover using a robot.

[0044] Example 2

[0045] The present embodiment provides a thorium target dissolution system, comprising the thorium target dissolution device described in Example 1, wherein the thorium target dissolution device is located inside a hot chamber, a shearing machine is provided on one side of the thorium target dissolution device, and the shearing machine is used to shear the thorium target. A first manipulator is provided on one side of the shearing machine, and the first manipulator is used to transfer the thorium target sent from the disassembled hot chamber to the workpiece placement slot of the shearing machine. A collecting element is provided at the blanking port of the shearing machine. In the present embodiment, the collecting element adopts a collecting basket, and a second manipulator and a robotic arm are provided between the collecting basket and the thorium target dissolution device described in Example 1, and the second manipulator is used to send the sheared thorium target block in the collecting basket into the dissolution tank.

[0046] In this embodiment, the first manipulator and the second manipulator can both be existing hot chamber manipulators, and a clamping mechanism is provided at the end thereof, which can clamp the top cover and the fixing bolts between the top cover and the tank body. The manipulator can take and place the top cover on the tank body and rotate the fixing bolts.

[0047] The first mechanical arm and the second mechanical mobile phone clamping mechanism can all adopt existing technologies, which will not be described in detail here.

[0048] The first manipulator and the second manipulator are both slave manipulators in an existing master-slave manipulator system. The active manipulator in the master-slave manipulator system is located outside the hot chamber, and the staff drives the slave manipulator to work by controlling the active manipulator.

[0049] The hot chamber in this embodiment is a dissolution hot chamber, and a material transmission channel is provided between the dissolution hot chamber and the disassembly hot chamber. The setting form of the material transmission channel can adopt the existing technology. The manipulator in the disassembly hot chamber places the thorium target in the cooling trap in the hanging basket, and transfers the hanging basket to the transfer tank of the transfer vehicle. The transfer vehicle can adopt the existing equipment. The transfer vehicle moves to the dissolution hot chamber through the material transmission channel, and the hanging basket is taken out of the dissolution hot chamber by the first manipulator, and then the thorium target is transferred to the shearing machine by the first manipulator.

[0050] Example 3

[0051] This embodiment provides a working method of the thorium target dissolution system described in Embodiment 2, comprising the following steps:

[0052] Step 1: The first manipulator places the thorium target on the shearing machine, and the shearing machine shears the thorium target, and the sheared thorium target block falls into the collecting element;

[0053] Step 2: The second manipulator places the thorium target block into the dissolving tank, and then the second manipulator covers the tank body with a top cover, and adds nitric acid solution and hydrofluoric acid catalyst into the dissolving tank through the nitric acid solution feeding pipe and the hydrofluoric acid catalyst feeding pipe respectively;

[0054] Step 3: Start the heating element and the gas supply mechanism, the heating element heats the dissolved liquid to a constant set temperature, and the gas supply mechanism bubbles the dissolved liquid through the bubbling tube;

[0055] Step 4: After the dissolution reaction has been set for a certain time, the dissolved solution is evaporated and concentrated.

[0056] In a practical application of this embodiment, the mass of a single thorium target is about 60g. The thorium target is sheared into 2-4mm cubic pieces using a shearing machine and transferred to a dissolving tank using a second manipulator. Then, the top cover is fixed to the top of the tank body using the second manipulator, 450mL of 10-12M nitric acid is added to the dissolving tank through a nitric acid solution feed pipe, and 50mL of 0.1M-0.2M hydrofluoric acid is added to the dissolving tank through a hydrofluoric acid catalyst feed pipe. At the same time, the bubbling tube and the discharge tube are opened to steadily introduce air, and the air pore diameter of the bubbling tube is about 2mm. The electric heating jacket is turned on to dissolve the The liquid is heated to a constant temperature of 100-120°C, and the constant temperature is controlled by a temperature detection element; the condensation reflux device is turned on to condense and reflux the evaporated dissolved liquid into a waste liquid bottle, and sampling and detection are performed through a manual negative pressure liquid sampler during the process. The dissolution reaction lasts for 2 hours to obtain a thorium nitrate dissolved liquid, and the concentration of thorium in the solution is measured. The mass of the dissolved thorium is 59.3g; the dissolved thorium nitrate solution is evaporated and concentrated at a temperature of 100-110°C, and the condensed refluxed solution is collected in a waste liquid bottle. In this process, 2 / 3 of the dissolved liquid is evaporated to reduce the volume of the dissolved liquid and remove fluoride ions in the dissolved liquid.

[0057] In another practical application of this embodiment, the mass of a single thorium target is about 60g. The thorium target is sheared into 2-4mm cubic pieces using a shearing machine and transferred to a dissolving tank using a second manipulator. 500mL of 10-12M nitric acid is added to the thorium target dissolving device through a nitric acid solution feeding pipe, and 10mL of 0.1M-0.2M hydrofluoric acid is added to the thorium target dissolving device through a hydrofluoric acid catalyst feeding pipe. At the same time, the bubbling tube and the discharge tube are opened to steadily introduce air, and the air pore diameter of the bubbling tube is about 2mm. The electric heating jacket is turned on to heat the solution at a constant temperature. Heat to about 80°C and control the constant temperature through a temperature detection element; turn on the condensation reflux device to condense and reflux the evaporated solution into a waste liquid bottle. During the process, sampling and detection are carried out through a manual negative pressure liquid sampler. The dissolution reaction lasts for 2 hours to obtain a thorium nitrate solution. The concentration of thorium in the solution is measured, and the mass of the dissolved thorium is 34.5g; the dissolved thorium nitrate solution is evaporated and concentrated at a temperature of 100-110°C, and the condensed reflux solution is collected in a waste liquid bottle. This process evaporates 2 / 3 of the solution to reduce the volume of the solution and remove fluoride ions in the solution.

[0058] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A thorium target dissolution device, characterized in that: The invention comprises a heating element, above which a dissolving tank is arranged, the dissolving tank comprises a tank body with an open top, a top cover is detachably connected to the top of the tank body, a nitric acid solution feeding pipe and a hydrofluoric acid catalyst feeding pipe are arranged on the top cover, a discharge pipe is arranged on the top cover, an exhaust pipe and a bubbling pipe are also arranged on the top cover, the bubbling pipe is connected to a gas supply mechanism through a gas pipeline to bubble the dissolved liquid in the tank body, and the exhaust pipe is connected to a condensation reflux device.

2. A thorium target dissolution device as claimed in claim 1, characterized in that: A first fixing plate is disposed at the bottom edge of the top cover, and a second fixing plate matching the first fixing plate is disposed on the top of the tank body. The first fixing plate and the second fixing plate are detachably fixedly connected by a plurality of threaded fasteners after being fitted together.

3. A thorium target dissolution device as claimed in claim 2, characterized in that: A sealing ring is arranged between the first fixing plate and the second fixing plate.

4. A thorium target dissolution device as claimed in claim 1, characterized in that: The heating element adopts an electric heating sleeve.

5. A thorium target dissolution device as claimed in claim 1, characterized in that: The top cover is also connected with a temperature detection element.

6. A thorium target dissolution device as claimed in claim 1, characterized in that: The dissolving tank is made of titanium 35 alloy.

7. A thorium target dissolution system, characterized in that: The thorium target dissolving device comprises the thorium target dissolving device according to any one of claims 1 to 6, and further comprises a shearing machine, wherein a first manipulator is provided on one side of the shearing machine to transfer the thorium target sent into the dissolving hot chamber to the shearing machine, a collecting element is provided below the drop opening of the shearing machine, and a second manipulator is provided between the collecting element and the thorium target dissolving device to place the sheared thorium target block into the dissolving tank.

8. A working method of the thorium target dissolution system according to claim 7, characterized in that: The first manipulator puts the thorium target sent into the dissolution hot chamber into the shearing machine, and the shearing machine shears the thorium target, and the sheared thorium target block falls into the collecting element; The second manipulator puts the thorium target block into the dissolving tank, and adds the nitric acid solution and the hydrofluoric acid catalyst into the dissolving tank through the nitric acid solution feeding pipe and the hydrofluoric acid catalyst feeding pipe respectively; The heating element and the gas supply mechanism are started, the heating element heats the dissolved liquid to a constant set temperature, and the gas supply mechanism bubbles the dissolved liquid through the bubbling tube until the dissolution reaction is completed.

9. The operating method of the thorium target dissolution system according to claim 8, characterized in that: The constant set temperature is 100-120°C.

10. The operating method of the thorium target dissolution system according to claim 8, characterized in that: The nitric acid solution is a 10M-12M nitric acid solution, and the hydrofluoric acid catalyst is a 0.1M-0.2M hydrofluoric acid solution.

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