CN210401006U - Device for preparing saturated dissolved oxygen water - Google Patents
Device for preparing saturated dissolved oxygen water Download PDFInfo
- Publication number
- CN210401006U CN210401006U CN201921319676.1U CN201921319676U CN210401006U CN 210401006 U CN210401006 U CN 210401006U CN 201921319676 U CN201921319676 U CN 201921319676U CN 210401006 U CN210401006 U CN 210401006U
- Authority
- CN
- China
- Prior art keywords
- unit
- air inlet
- humidifying
- pipe
- dissolved oxygen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn - After Issue
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 59
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 55
- 239000001301 oxygen Substances 0.000 title claims abstract description 55
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 55
- 229920006395 saturated elastomer Polymers 0.000 title claims abstract description 28
- 238000007789 sealing Methods 0.000 claims abstract description 29
- 229920001971 elastomer Polymers 0.000 claims abstract description 20
- 239000012528 membrane Substances 0.000 claims description 39
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 18
- 239000007788 liquid Substances 0.000 claims description 17
- 239000012153 distilled water Substances 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 11
- 239000011780 sodium chloride Substances 0.000 claims description 9
- 238000012360 testing method Methods 0.000 claims description 3
- 229920003229 poly(methyl methacrylate) Polymers 0.000 claims description 2
- 239000004926 polymethyl methacrylate Substances 0.000 claims description 2
- 230000006835 compression Effects 0.000 claims 1
- 238000007906 compression Methods 0.000 claims 1
- 230000000694 effects Effects 0.000 claims 1
- 238000012795 verification Methods 0.000 abstract description 7
- 238000002360 preparation method Methods 0.000 abstract description 6
- 239000007789 gas Substances 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 239000003638 chemical reducing agent Substances 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000013013 elastic material Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 229920000295 expanded polytetrafluoroethylene Polymers 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 239000011555 saturated liquid Substances 0.000 description 1
Images
Abstract
The utility model provides a preparation saturated dissolved oxygen water device, structurally has four units to constitute: an air inlet pipe unit, a humidifying pipe unit, a mixing pipe unit and a heater unit. The air inlet pipe unit is partially inserted into the humidifying pipe unit and is fixed through a sealing ring, a gasket, a sealing ring and an air inlet pipe cover shell; the humidifying pipe is partially inserted into the mixing pipe unit and is fixed through a sealing ring, a gasket, a sealing ring and a humidifying pipe cover shell; one end of the mixing pipe unit is connected with the humidifying pipe unit, and the other end of the mixing pipe unit is provided with elastic rubber; the heater unit is cylindrical, and the air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are tightly clamped in the heater unit, and are heated through the cylindrical groove of the heater unit. The utility model aims at providing a accord with the relevant requirement of national metrological verification regulation JJJG 291, 2018 "dissolved oxygen apparatus verification regulation" regulation of the people's republic of China, the device of preparation saturation dissolved oxygen water that can be on-the-spot quick convenient.
Description
Technical Field
The utility model belongs to dissolved oxygen apparatus quality control field especially prepares saturated dissolved oxygen water as the etalon and is used for the measurement calibration of dissolved oxygen apparatus.
Background
The dissolved oxygen determinator is mainly used for determining the concentration of constant dissolved oxygen in water, and has the working principle that oxygen permeates a diaphragm to be reduced by a working electrode, so that diffusion current in direct proportion to the concentration of oxygen is generated, and the concentration of the dissolved oxygen in water is obtained by measuring the current.
Dissolved oxygen is one of the important indexes for judging the water quality pollution degree, and a dissolved oxygen tester used in the field of environmental monitoring belongs to a compulsory verification work measuring instrument. The metering performance of the dissolved oxygen meter has the following typical characteristics: namely, the performance level of the instrument which is newly delivered from the factory is high, and the performance of the instrument is influenced by the fact that the electrode is polluted or damaged in different degrees in the actual use process of a user, so that the calibration needs to be carried out regularly to ensure the accuracy and reliability of the measurement result.
At present, the saturated dissolved oxygen water is prepared by a water saturation gas method according to the saturated dissolved oxygen water preparation of identification water in an identification standard device mentioned in JJG 291-2018 (verification procedure of dissolved oxygen measuring instrument) 5.1.2 and identification water mentioned in matched equipment, wherein various equipment combinations such as a precise constant-temperature water tank, a stopwatch, a thermometer, a barometer and a bubbler are mainly used for the verification of the dissolved oxygen measuring instrument, the preparation efficiency of the method is low, the time is up to 90 minutes, the used equipment is large in volume, the types of the combined equipment are too many, the method is not suitable for preparing the saturated dissolved oxygen water on site, and the detection process of the dissolved oxygen measuring instrument mostly occurs on site.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a preparation saturation dissolved oxygen water device accords with the relevant requirement of national measurement and verification regulation JJJG 291- "dissolved oxygen apparatus examination regulation" of the people's republic of China for dissolved oxygen apparatus examination, more reliable and accurate than the examination result of current "gas saturation water method". More specifically, the device for preparing the saturated dissolved oxygen water can be used for rapidly and conveniently preparing the saturated dissolved oxygen water on site, on one hand, the problem that the efficiency is low and the consumption is long in the process of preparing the saturated dissolved oxygen water in a laboratory at present is solved, and on the other hand, the embarrassing current situation that the existing equipment is not easy to move to the site for preparing the saturated dissolved oxygen water can be solved.
A device for preparing saturated dissolved oxygen water structurally comprises four units: an air inlet pipe unit, a humidifying pipe unit, a mixing pipe unit and a heater unit. The air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are mainly made of polymethyl methacrylate (namely transparent acrylic material); the air inlet pipe unit is partially inserted into the humidifying pipe unit and is fixed through a sealing ring, a gasket and an air inlet pipe cover shell; the humidifying pipe unit is partially inserted into the mixing pipe unit and is fixed through a sealing ring, a gasket and a humidifying pipe cover shell; the mixing tube unit is provided with distilled water or sodium chloride solution, one end of the mixing tube unit is connected with the humidifying tube unit, the other end of the mixing tube unit is provided with elastic rubber, and an electrode of a dissolved oxygen determinator to be detected directly penetrates into the mixing tube unit through the elastic rubber to be measured; the heater unit is cylindrical, and the air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are tightly clamped in the heater unit, and are heated through the cylindrical groove of the heater unit.
The technical scheme of the utility model is to realize a preparation saturation dissolved oxygen water device to carry the detection scene very easily. Air from the air pump enters the mixing tube unit through the air inlet tube unit and a filter membrane at the top end of the humidifying tube unit respectively, wherein the filter membrane belongs to a waterproof and breathable membrane, allows air to freely enter, and prevents liquid from flowing back during gas-liquid mixing.
The humidifying pipe unit is used for humidifying air before entering the mixing pipe unit, distilled water is arranged at the bottom of the humidifying pipe unit, and the bottom of the humidifying pipe unit is sealed by a filter membrane. Therefore, air from the air pump enters the humidifying pipe unit through the filter membrane at the top of the air inlet pipe unit, bubbles upwards through the distilled water, enters the mixing pipe unit through the filter membrane at the top end of the humidifying pipe unit, bubbles upwards through the distilled water or the sodium chloride solution, and is discharged into the atmosphere through the micropores of the elastic rubber arranged at the top of the mixing pipe unit.
The utility model discloses an adjust air pump and filter membrane parameter control bubble size and hydrostatic pressure height so that gas-liquid mixing efficiency maximize and make bubble atmospheric pressure difference minimizing. The whole device for preparing the saturated dissolved oxygen water is placed in a constant temperature control environment through a heating pipe unit, and the saturated dissolved oxygen water after temperature and pressure saturation can be used for subsequent verification.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of an embodiment of the present invention;
FIG. 2 is an enlarged schematic view of the present invention;
in fig. 1: 1. an air pump; 2. a pressure reducer; 3. an air duct; 4. an air inlet interface; 5. an air inlet pipe; 6. a first filter screen; 7. A first filter membrane; 8. a first sealing ring; 9. a first gasket; 10. a second sealing ring; 11. an air inlet pipe cover shell; 12. a humidifying pipe; 13. a second filter screen; 14. a second filter membrane; 15. a third sealing ring; 16. a second gasket; 17. a fourth sealing ring; 18. a humidifying pipe cover shell; 19. a mixing tube; 20. an elastic rubber; 21. a dissolved oxygen meter electrode; 22. a heating pipe unit; 23. dissolved oxygen tester host computer.
Detailed Description
In a device for preparing saturated dissolved oxygen water as shown in fig. 1, air from an air pump 1 flows into a humidifying pipe 12 through an air inlet interface 4 at a proper rate through an air guide pipe 3 under the regulation of a pressure reducer 2. Pressure builds up at the concave side of the filter membrane one 7 of the inlet duct 5 so that the gas flow enters the humidifying pipe 12 through the micropores of the filter membrane one 7. The bottom of the humidifying pipe 12 is filled with a part of distilled water, and as the pressure in the humidifying pipe 12 is accumulated at the concave side of the second filter membrane 14, the distilled water flows into the mixing pipe 19 at the side of the convex side of the second filter membrane.
In a device for preparing saturated oxygen-dissolved water as shown in fig. 1, both the first filter membrane 7 and the second filter membrane 14 are made of a cap-shaped membrane made of a suitable elastic material such as expanded polytetrafluoroethylene, which is a waterproof and air-permeable membrane that allows one-way flow of pressurized air and prevents reverse flow of liquid.
As shown in FIG. 1, when air flows out of the second filter 14 at the top end of the humidifying pipe, it forms small bubbles with a diameter of about 1mm, and then rises through the liquid in the mixing pipe 19 to achieve gas-liquid mixing. Small bubbles can maximize the ratio of liquid volume to air surface area, thereby reducing saturation time.
The device for preparing saturated dissolved oxygen water as shown in fig. 2 structurally comprises four units: an air inlet pipe unit, a humidifying pipe unit, a mixing pipe unit and a heater unit. The air inlet pipe unit is partially inserted into the humidifying pipe unit and is fixed through a sealing ring, a gasket and an air inlet pipe cover shell; the humidifying pipe unit is partially inserted into the mixing pipe unit and is fixed through a sealing ring, a gasket and a humidifying pipe cover shell; the mixing tube unit is provided with distilled water or sodium chloride solution, one end of the mixing tube unit is connected with the humidifying tube unit, the other end of the mixing tube unit is provided with elastic rubber, and an electrode of a dissolved oxygen determinator to be detected directly penetrates into the mixing tube unit through the elastic rubber to be measured; the heater unit is cylindrical, and the air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are tightly clamped in the heater unit and are heated through the cylindrical groove of the heater unit.
As shown in fig. 2, the air inlet pipe unit mainly includes an air inlet port 4, an air inlet pipe 5, a first filter screen 6, a first filter membrane 7, a first seal ring 8, a first gasket 9, a second seal ring 10, and an air inlet pipe cover shell 11. The air received by the air inlet interface 4 is led to the air inlet pipe 5; the filter screen I6 is arranged below the filter membrane I7 to play a role in supporting the filter membrane I7; the first filter membrane 7 is fixed at one end of the air inlet pipe 5, which penetrates into the humidifying pipe 12; the first sealing ring 8, the first gasket 9, the second sealing ring 10 and the air inlet pipe cover shell 11 are sequentially overlapped and covered on the first filter membrane 7, so that the air inlet pipe is ensured to play a role in sealing and fixing when sliding relative to the humidifying pipe.
As shown in fig. 2, the humidifying pipe unit mainly includes a humidifying pipe 12, a second filter screen 13, a second filter membrane 14, a third sealing ring 15, a second gasket 16, a fourth sealing ring 17, and a cover shell of the humidifying pipe. The humidifying pipe is of a hollow structure, the internal volume of the humidifying pipe is 100ml, and half of the humidifying pipe is filled with distilled water, so that in a relatively small dead zone above water, rapid flushing of air is ensured, and complete temperature balance and water vapor balance of the air are completed before the air enters the mixing pipe 19; the second filter screen 13 is arranged below the second filter membrane 14 to play a role of supporting the second filter membrane 14; the third sealing ring 15, the second gasket 16, the fourth sealing ring 17 and the humidifying pipe cover 18 are sequentially overlapped on the second filter membrane 14 to ensure that the humidifying pipe plays a role in sealing and fixing when sliding relative to the mixing pipe.
In a device for preparing saturated dissolved oxygen water as shown in fig. 2, the mixing tube unit mainly comprises a mixing tube 19 and an elastic rubber 20 in structure. The mixing tube is of a hollow structure, the volume of the mixing tube is 200ml, and when distilled water or a sodium chloride solution is used, half space of the mixing tube can be filled with the distilled water or the sodium chloride solution; the elastic rubber 20 is made of elastic rubber provided with a hole in the middle of the micro exhaust hole and is arranged at the top end of the mixing pipe 19; in a normal state, the micropores are closed, air from the outside cannot enter the liquid which is subjected to interference and saturation, and in the detection process, excessive air is discharged from the micropores of the elastic rubber 20 through the action of pressure; the opening provided in the middle of the elastic rubber can be inserted by compressing to accommodate dissolved oxygen meter electrodes of different diameter sizes, and the expanded state of the opening plays a sealing role.
As shown in figure 2, the device for preparing saturated dissolved oxygen water is characterized in that the heater unit is cylindrical and is a constant temperature control device, and the temperature control module is used for controlling the temperature of the heating block. The air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are tightly clamped in the air inlet pipe unit, and are heated through the cylindrical grooves of the heating blocks on the air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit, so that the gas and the liquid are fully mixed; the liquid sample in the mixing tube for gas-liquid mixing can be visually observed through the opening on the upper surface of the cylindrical groove of the heating block. The present invention uses a simple feedback control system to accomplish the design of the heater unit, such thermostatic control systems are well known and commercially available, and therefore the device is not described in detail herein.
A device for preparing saturated dissolved oxygen water comprises the following main process flows: (1) placing 50ml of water into the humidifying tube 12, and inserting the humidifying tube 12 into the mixing tube 19; (2) the mixing tube 19 is filled with 100ml of distilled water or sodium chloride solution; (3) inserting the installed air inlet pipe unit, humidifying pipe unit and mixing pipe unit into the cylindrical groove of the heater unit (preheating to a desired temperature); (4) the air duct 3 is connected with an air inlet connector 4 to an air inlet pipe 5; (5) the compressed air formed by the air pump 1 flows through the air duct 3, the air inlet interface 4 and the air inlet pipe 5 to the humidifying pipe 12 under the regulation of the pressure reducer 2, and bubbles are allowed to pass through the liquid for a period of time, which may be ten minutes (although in the present invention, the temperature equilibrium is usually reached within five minutes, and sufficient gas-liquid mixing is achieved within less than ten minutes in the case of the maximum fluid volume); (6) the air inlet interface 4 and the air duct 3 are disconnected with the air inlet pipe 5, so that the humidifying pipe 12 can be freely stretched in the mixing pipe 19; (7) by extending the humidifying pipe 12 into the mixing pipe 19, the saturated liquid after discharging the excess air required for mixing can be used when gas and liquid are mixed; (8) the dissolved oxygen meter electrode 21 is inserted into the mixing tube 19 through the compressible elastic rubber 20 to test saturated dissolved oxygen water, and the test result is analyzed by recording the data of the dissolved oxygen meter main unit 23.
Claims (7)
1. A device for preparing saturated dissolved oxygen water is characterized in that: structurally, the device consists of four units: the humidifier comprises an air inlet pipe unit, a humidifying pipe unit, a mixing pipe unit and a heater unit; the air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are mainly made of polymethyl methacrylate; the air inlet pipe unit is partially inserted into the humidifying pipe unit and is fixed through a sealing ring, a gasket and an air inlet pipe cover shell; the humidifying pipe is partially inserted into the mixing pipe unit and is fixed through a sealing ring, a gasket and a humidifying pipe cover shell; distilled water or sodium chloride solution is arranged in the mixing tube unit, one end of the mixing tube unit is connected with the humidifying tube unit, the other end of the mixing tube unit is provided with elastic rubber, and an electrode of a dissolved oxygen determinator to be detected directly penetrates into the mixing tube unit through the elastic rubber to be measured; the heater unit is cylindrical, and the air inlet pipe unit, the humidifying pipe unit and the mixing pipe unit are tightly clamped in the heater unit and are heated through the cylindrical groove of the heater unit.
2. The apparatus for preparing saturated dissolved oxygen water according to claim 1, wherein: the air inlet pipe unit mainly comprises an air inlet interface, an air inlet pipe, a filter screen I, a filter membrane I, a seal ring I, a gasket I, a seal ring II and an air inlet pipe cover shell in structure; the air received by the air inlet interface is led to the air inlet pipe; the filter screen I is arranged below the filter membrane I to play a role in supporting the filter membrane I; the first filter membrane is fixed at one end of the air inlet pipe, which extends into the humidifying pipe; the first sealing ring, the first gasket, the second sealing ring and the air inlet pipe cover shell are sequentially overlapped and covered on the first filter membrane, so that the air inlet pipe is ensured to play a role in sealing and fixing when sliding relative to the humidifying pipe.
3. The apparatus for preparing saturated dissolved oxygen water according to claim 1, wherein: the humidifying pipe unit mainly comprises a humidifying pipe, a filter screen II, a filter membrane II, a seal ring III, a gasket II, a seal ring IV and a humidifying pipe cover shell in structure; the humidifying pipe is of a hollow structure, the internal volume of the humidifying pipe is 100ml, and half of the humidifying pipe is filled with distilled water, so that air is ensured to be rapidly flushed in a relatively small dead zone above water, and meanwhile, the complete temperature balance and water vapor balance of the air are completed before the air enters the mixing pipe; the filter screen II is arranged below the filter membrane II to play a role in supporting the filter membrane II; and the third sealing ring, the second gasket, the fourth sealing ring and the humidifying pipe cover shell are sequentially overlapped on the second filter membrane to ensure that the humidifying pipe plays a role in sealing and fixing when sliding relative to the mixing pipe.
4. The apparatus for preparing saturated dissolved oxygen water according to claim 1, wherein: the mixing tube unit mainly comprises a mixing tube and elastic rubber in structure; the mixing tube is of a hollow structure, the volume of the mixing tube is 200ml, and when distilled water or a sodium chloride solution is used, half space of the mixing tube can be filled with the distilled water or the sodium chloride solution; the elastic rubber is made of elastic rubber provided with a hole in the middle of the tiny exhaust hole and is arranged at the top end of the mixing pipe; under normal conditions, the micropore is airtight, and the air that comes from the external world can't get into to disturb through the liquid of saturation, and in the testing process, excessive air is because pressure effect, through flexible elastic rubber, discharges from its micropore.
5. The apparatus for preparing saturated dissolved oxygen water according to claim 2, wherein: the filter membrane is a waterproof, breathable membrane that allows air to freely enter, preventing reverse flow of liquid.
6. The apparatus for preparing saturated dissolved oxygen water according to claim 3, wherein: the filter membrane is a waterproof and breathable membrane, which allows air to freely enter and can prevent liquid from flowing reversely.
7. The apparatus for preparing saturated dissolved oxygen water according to claim 4, wherein: the elastic rubber may be inserted by compression to accommodate dissolved oxygen meter electrodes of different diameter sizes, the expanded state of which acts as a seal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921319676.1U CN210401006U (en) | 2019-08-15 | 2019-08-15 | Device for preparing saturated dissolved oxygen water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921319676.1U CN210401006U (en) | 2019-08-15 | 2019-08-15 | Device for preparing saturated dissolved oxygen water |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210401006U true CN210401006U (en) | 2020-04-24 |
Family
ID=70338084
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921319676.1U Withdrawn - After Issue CN210401006U (en) | 2019-08-15 | 2019-08-15 | Device for preparing saturated dissolved oxygen water |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210401006U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110320091A (en) * | 2019-08-15 | 2019-10-11 | 南京嘉恒仪器设备有限公司 | It is a kind of to prepare saturation dissolved oxygen water installations |
| CN110320091B (en) * | 2019-08-15 | 2024-06-25 | 南京嘉恒仪器设备有限公司 | Device for preparing saturated dissolved oxygen water |
-
2019
- 2019-08-15 CN CN201921319676.1U patent/CN210401006U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110320091A (en) * | 2019-08-15 | 2019-10-11 | 南京嘉恒仪器设备有限公司 | It is a kind of to prepare saturation dissolved oxygen water installations |
| CN110320091B (en) * | 2019-08-15 | 2024-06-25 | 南京嘉恒仪器设备有限公司 | Device for preparing saturated dissolved oxygen water |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20200424 Effective date of abandoning: 20240625 |
|
| AV01 | Patent right actively abandoned |
Granted publication date: 20200424 Effective date of abandoning: 20240625 |