Environmental radon concentration detector based on scintillator chamber

Abstract

The invention discloses an environmental radon concentration detector based on a scintillator chamber, and the detector comprises a scintillation chamber in which a sampled radon-containing gas enters the scintillation chamber through a gas inlet, and an alpha ray generated by radon decay reacts with ZnS (Ag) to generate an optical signal; the photomultiplier is used for converting an optical signal into an electric signal; the pre-amplifier is used for amplifying and shaping the electric signal to obtain an amplified electric signal; the signal acquisition module is used for acquiring the amplified electric signal; and the concentration calculation module is used for calculating the radon concentration in the environment according to the amplified electric signal in combination with the decay law of the radon and the daughters thereof and the measurement time set by the user. According to the invention, radon and daughter decayed alpha rays in sampling gas react with the coating of the scintillation chamber to serve as the basis of radon concentration calculation, and the environmental radon concentration detection accuracy is improved from the internal structure design of the chamber.

Description

Technical Field

[0001] The invention relates to the technical field of environmental radon gas concentration detection, and in particular to an environmental radon concentration detector based on a scintillator chamber. Background Art

[0002] Radon is a radioactive inert gas that is colorless and odorless. It is produced by the decay of radium and is the only natural radioactive gas in nature. Its density is 9.73kg / m3, which is 7.5 times heavier than air. It is very easy to hide in the indoor air. Since building materials are the main source of indoor radon, especially natural stone containing radioactive elements, it is easy to release radon. The radon content in granite exceeds the standard and is highly radioactive.

[0003] Because it is colorless and odorless, the harm of radon to the human body is also hidden. The harm of radon to the human body is mainly through the continuous accumulation of radon daughters intercepted by the respiratory system in the lungs, which causes lung cancer. The World Health Organization lists radon as one of the 19 major environmental carcinogens. Inhaling more radon gas can cause leukemia. Radon can also kill sperm and make people lose their fertility. Radon can also affect the nervous system and make people depressed. In summary, radon gas has become a super killer of home health. With the deepening of people's understanding of radon and the increasing attention paid to radon, the instruments for measuring radon are also constantly being improved and improved.

[0004] Traditional methods for measuring radon include ionization current method, scintillation pulse method and emanation method. However, the existing methods for measuring radon concentration require manual interpretation of data and complex calculations, which not only have low detection efficiency, but are also prone to human error. Therefore, how to improve the accuracy and efficiency of environmental radon concentration detection is a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: how to provide an environmental radon concentration detector based on a scintillator chamber, using the α rays of the decay of radon and its daughters in the sampled gas and the reaction of the coating of the scintillation chamber as the basis for radon concentration calculation, and improving the accuracy of environmental radon concentration detection from the design of the internal structure of the chamber.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A scintillator chamber-based environmental radon concentration detector, comprising:

[0008] The scintillation chamber is provided with an air inlet and an air outlet, and the inner surface of the scintillation chamber is sprayed with a ZnS (Ag) layer; the radon-containing gas sampled from the environment enters the scintillation chamber through the air inlet, and the alpha rays generated by the decay of radon react with the ZnS (Ag) to generate a light signal;

[0009] A photomultiplier tube, used to convert the optical signal generated by the ZnS (Ag) layer into an electrical signal;

[0010] A preamplifier is used to amplify and shape the electrical signal converted by the photomultiplier tube to obtain an amplified electrical signal;

[0011] A signal acquisition module, used for acquiring the amplified electrical signal;

[0012] The concentration calculation module is used to calculate the radon concentration in the environment based on the amplified electrical signal combined with the decay law of radon and its daughters.

[0013] Preferably, the scintillation chamber is a spherical structure; the interior of the scintillation chamber is divided into four small chambers by a baffle.

[0014] Preferably, the outer surface of the scintillation chamber is sprayed with reflective paint.

[0015] Preferably, it also includes:

[0016] The display module is used to display the radon concentration calculated by the concentration calculation module.

[0017] Preferably, it also includes:

[0018] The suitcase, the scintillation chamber, the photomultiplier tube, the preamplifier, the signal acquisition module and the concentration calculation module are arranged in the body of the suitcase.

[0019] Preferably, a lithium battery is provided in the suitcase, and the lithium battery is used to power the photomultiplier tube, the preamplifier, the signal acquisition module, and the concentration calculation module.

[0020] Compared with the prior art, the environmental radon concentration detector based on the scintillator chamber in the present invention has the following beneficial effects:

[0021] In the environmental radon concentration detector of the present invention, firstly, the interior of the scintillation chamber is divided into a plurality of small chambers to increase the contact area with the sampled radon-containing gas as much as possible, and the special radon-containing gas path realizes the uniformity of the sampled gas inside the chamber, and also ensures that the sampled gas can be quickly removed and will not be enriched in a small area, realizing the improvement of the accuracy of environmental radon concentration detection from the internal structure design of the chamber, and the concentration calculation module directly calculates the radon concentration in the environment according to the amplified electrical signal combined with the decay law of radon and its daughters and the measurement time set by the user, without the need for manual interpretation of data and complex calculations, thereby improving the accuracy and efficiency of radon concentration detection in the environment. Secondly, in terms of electronics, the possibility of long-term field operations is considered, and a large-capacity rechargeable lithium battery and a circuit low-power design are provided, so that continuous measurements of more than 20 hours can be performed outdoors, and the selection of components takes into account certain factors such as national defense security, and all components are selected from products of domestic manufacturers, realizing complete autonomous control. Then the internal unique algorithm allows users to calibrate only the 60-minute measurement cycle scale factor when using it. After setting it to other measurement time, the scale factor will be automatically calculated, realizing the rapid determination of radon concentration. Finally, the device is compact and portable, with a suitcase design, which is convenient for quick installation and disassembly maintenance. Combined with the 5.6-inch LCD display and the compact and simple layout of the buttons, the size and weight of the instrument are greatly reduced, thus achieving the characteristics of portability, which is suitable for field detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to make the purpose, technical solution and advantages of the invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings, in which:

[0023] Figure 1 The figure is the logic block diagram of the ambient radon concentration detector based on the scintillator chamber.

[0024] Figure 2 Schematic diagram of the structure of the scintillation chamber.

[0025] Figure 3 and Figure 4 This is a physical example of an environmental radon concentration detector.

[0026] The reference numerals in the drawings of the specification include: a scintillation chamber 1 , an air inlet 2 , and an air outlet 3 . DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but only represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0028] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The following is a further detailed description through specific implementation methods:

[0030] Example:

[0031] This embodiment discloses an environmental radon concentration detector based on a scintillator chamber.

[0032] like Figure 2As shown, an environmental radon concentration detector based on a scintillator chamber comprises:

[0033] The scintillation chamber 1 is provided with an air inlet 2 and an air outlet 3, and the inner surface of the scintillation chamber 1 is sprayed with a ZnS (Ag) layer; the radon-containing gas sampled from the environment enters the scintillation chamber through the air inlet 2, and the alpha rays generated by the decay of radon react with the ZnS (Ag) to generate a light signal;

[0034] A photomultiplier tube, used to convert the optical signal generated by the ZnS (Ag) layer into an electrical signal;

[0035] A preamplifier is used to amplify the electrical signal converted by the photomultiplier tube to obtain an amplified electrical signal;

[0036] A signal acquisition module, used for acquiring the amplified electrical signal;

[0037] The concentration calculation module is used to calculate the radon concentration in the environment based on the amplified electrical signal combined with the decay law of radon and its daughters (and the measurement time set by the user).

[0038] In this embodiment, the relationship between the electrical signal and the radon concentration needs to be established in advance through experiments or theoretical models. The concentration calculation module determines the radon concentration in the environment based on the amplified electrical signal and the pre-established relationship between the electrical signal and the radon concentration.

[0039] The display module is used to display the radon concentration calculated by the concentration calculation module.

[0040] In the environmental radon concentration detector of the present invention, firstly, the interior of the scintillation chamber is divided into a plurality of small chambers to increase the contact area with the sampled radon-containing gas as much as possible, and the special radon-containing gas path realizes the uniformity of the sampled gas inside the chamber, and also ensures that the sampled gas can be quickly removed and will not be enriched in a small area, realizing the improvement of the accuracy of environmental radon concentration detection from the internal structure design of the chamber, and the concentration calculation module directly calculates the radon concentration in the environment according to the amplified electrical signal combined with the decay law of radon and its daughters and the measurement time set by the user, without the need for manual interpretation of data and complex calculations, thereby improving the accuracy and efficiency of radon concentration detection in the environment. Secondly, in terms of electronics, the possibility of long-term field operations is considered, and a large-capacity rechargeable lithium battery and a circuit low-power design are provided, so that continuous measurements of more than 20 hours can be performed outdoors, and the selection of components takes into account certain factors such as national defense security, and all components are selected from products of domestic manufacturers, realizing complete autonomous control. Then the internal unique algorithm allows users to calibrate only the 60-minute measurement cycle scale factor when using it. After setting it to other measurement time, the scale factor will be automatically calculated, realizing the rapid determination of radon concentration. Finally, the device is compact and portable, with a suitcase design, which is convenient for quick installation and disassembly maintenance. Combined with the 5.6-inch LCD display and the compact and simple layout of the buttons, the size and weight of the instrument are greatly reduced, thus achieving the characteristics of portability, which is suitable for field detection.

[0041] like Figure 2 As shown, the scintillation chamber 1 is a spherical structure, and the photomultiplier tube is closely attached to the smooth end surface of the scintillation chamber (not shown in the figure). The interior of the scintillation chamber is divided into four small chambers by a baffle. By fully considering the range of α ions in the air, the detection efficiency is improved; when sampling radon-containing gas, the radon-containing gas flows evenly through each small cavity through the air inlet, so that the radon-containing gas fills the entire scintillation chamber evenly and balancedly.

[0042] The present invention sets the scintillation chamber as a spherical structure. Under the condition of equal volume, the surface area occupied by the sphere is the largest, so that the detection efficiency of the environmental radon concentration detector can be improved as much as possible. At the same time, a cross grid can be added inside the scintillation chamber to further increase the contact area between the air and the sphere, thereby improving the detection efficiency.

[0043] In the specific implementation process, the outer surface of the scintillation chamber is sprayed with reflective paint. The reflective paint sprayed on the outer surface of the scintillation chamber increases the probability of capturing light and reflects all the light emitted to the contact end face of the photomultiplier tube.

[0044] The specific implementation process also includes:

[0045] The suitcase, the scintillation chamber, the photomultiplier tube, the preamplifier, the signal acquisition module, and the concentration calculation module are arranged in the body of the suitcase. The design of the suitcase is convenient for users to carry.

[0046] The present invention realizes the portable design of the environmental radon concentration detector by installing the scintillation chamber and the photomultiplier tube, preamplifier, signal acquisition module and concentration calculation module in the suitcase. The existing environmental radon concentration detector often needs to be fixed in a certain place for use, while the environmental radon concentration detector in the present invention can be carried by the user, realizing convenient and fast environmental radon concentration detection.

[0047] In this embodiment, the appearance of the environmental radon concentration detector is designed as follows Figure 3 As shown, it is a black portable suitcase with the overall dimensions of length × width × height: 335 × 260 × 210 mm. Figure 4 , is the user operation panel, including the screen, buttons, air inlet and outlet, communication interface and power supply / charging interface.

[0048] The main components behind the suitcase are photomultiplier tubes, large-capacity lithium batteries, small vacuum pumps, scintillation chambers and electronics. The electronics are used to convert optical signals into electrical signals and to shape and amplify the signals. The domestic single-chip microcomputer HC32F4A0 is used as the control unit to realize signal collection and processing, human-computer interaction, control, output of radon content in the air and other functions. The large-capacity lithium battery and the appearance design of the suitcase are suitable for long-term field operations. The large-capacity lithium battery powers the photomultiplier tube, preamplifier, signal acquisition module, and concentration calculation module. Each circuit and module adopts a low-power design to increase the duration of outdoor operations.

[0049] During the specific implementation process, the thickness of the ZnS (Ag) layer sprayed on the inner surface of the scintillation chamber is designed so that the ZnS (Ag) layer only captures the α rays generated by the decay of radon-containing gases, but does not capture the β and γ rays generated during the decay of radon-containing gases, thereby filtering out interference factors in the measurement process.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. A scintillator chamber-based environmental radon concentration detector, characterized in that: include: The scintillation chamber is provided with an air inlet and an air outlet, and the inner surface of the scintillation chamber is sprayed with a ZnS (Ag) layer; the radon-containing gas sampled from the environment enters the scintillation chamber through the air inlet, and the alpha rays generated by the decay of radon react with the ZnS (Ag) to generate a light signal; A photomultiplier tube, used to convert the optical signal generated by the ZnS (Ag) layer into an electrical signal; A preamplifier is used to amplify and shape the electrical signal converted by the photomultiplier tube to obtain an amplified electrical signal; A signal acquisition module, used for acquiring the amplified electrical signal; The concentration calculation module is used to calculate the radon concentration in the environment based on the amplified electrical signal combined with the decay law of radon and its daughters.

2. The environmental radon concentration detector based on a scintillator chamber as claimed in claim 1, characterized in that: The scintillation chamber is a spherical structure; the interior of the scintillation chamber is divided into four small chambers by a baffle.

3. The environmental radon concentration detector based on a scintillator chamber as claimed in claim 1, characterized in that: The outer surface of the flashing chamber is sprayed with reflective paint.

4. The environmental radon concentration detector based on a scintillator chamber as claimed in claim 1, characterized in that: Also includes: The display module is used to display the radon concentration calculated by the concentration calculation module.

5. The environmental radon concentration detector based on a scintillator chamber as claimed in claim 1, characterized in that: Also includes: The suitcase, the scintillation chamber, the photomultiplier tube, the preamplifier, the signal acquisition module and the concentration calculation module are arranged in the body of the suitcase.

6. The environmental radon concentration detector based on a scintillator chamber as claimed in claim 5, characterized in that: A lithium battery is provided in the suitcase, and the lithium battery is used to power the photomultiplier tube, the preamplifier, the signal acquisition module, and the concentration calculation module.

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