CN215953293U - Device for measuring fineness of pulverized coal by diffraction scattering - Google Patents
Device for measuring fineness of pulverized coal by diffraction scattering Download PDFInfo
- Publication number
- CN215953293U CN215953293U CN202121430056.2U CN202121430056U CN215953293U CN 215953293 U CN215953293 U CN 215953293U CN 202121430056 U CN202121430056 U CN 202121430056U CN 215953293 U CN215953293 U CN 215953293U
- Authority
- CN
- China
- Prior art keywords
- lens
- primary air
- air pipe
- fineness
- center
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Abstract
A device for measuring the fineness of coal powder by diffraction scattering comprises a He-Ne laser, a spatial filter, a beam expanding lens, a primary air pipe, a receiving lens, a photoelectric detector, a USB data acquisition unit and a PC. A laser beam from a He-Ne laser is enhanced and stabilized through spatial filtering, after being expanded by a beam expanding lens, the laser beam is vertically irradiated on a coal powder particle group to be detected in a primary air pipe in parallel, generated diffraction light is converged by a focusing lens to form a diffraction pattern on a focal plane of the focusing lens, a photoelectric detector on the focal plane can perform photoelectric conversion on signals, USB data is collected and then sent to a PC, the size distribution of the coal powder particles can be quickly deduced back by adopting a pre-programmed formula and program, and the fineness of the coal powder is further calculated. The device has the advantages of no need of sampling, simple operation, convenience, rapidness, realization of online real-time measurement, simple structure and convenience in maintenance.
Description
Technical Field
The utility model relates to the technical field of laser diagnosis and measurement in thermal engineering, in particular to a device for measuring the fineness of coal dust by diffraction and scattering.
Background
With the continuous development of the industry, the coal energy is increasingly tense, so that the requirements on the quality components and the combustion efficiency of the coal are higher and higher. The non-uniformity of the coal dust concentration has a great influence on the combustion. If the concentration difference of the pulverized coal is too large, the combustion cannot be well organized, and flame deflection, coking, unstable combustion and the like can be caused. And the over-large or fine granularity of the coal powder can cause incomplete combustion, increased loss, reduced efficiency, increased energy consumption and the like. The coal powder pipeline is blocked due to the fact that the coal powder is uneven in concentration or inappropriate in particle size, and the blockage is eliminated by stopping or reducing the load in serious cases, so that great loss is caused, and the safe operation is influenced. The key problems of energy conservation, emission reduction and environmental protection in China are to improve the efficiency and reduce the emission of pollutants. The real-time online measurement of the concentration, the speed and the granularity of the pulverized coal particles in the pulverized coal pipeline plays an important role in energy conservation, emission reduction and optimal control. However, the flowing condition of the pulverized coal particles in the pulverized coal pipeline as a gas-solid two-phase flow is very complicated, which brings many difficulties to the measurement.
At present, the commonly used method for measuring the fineness of the coal dust particles is a sampling method, and the granularity of the coal dust is obtained by taking a coal dust sample out of a coal dust pipeline by using a constant-speed sampling pipe and then using a screening method and the like in a laboratory. The measuring method is long in time consumption, and actually cannot be controlled in real time to obtain the optimal pulverized coal granularity so as to be beneficial to combustion; the physical property parameters required by the ultrasonic method greatly change along with the working condition; and thirdly, an image method, which has specific requirements on gas-solid two-phase concentration and the like, is harsh in conditions and complicated to operate.
Therefore, advanced and rapid analysis means are urgent, and particularly, an effective coal quality real-time monitoring system is developed, so that a detection result is directly fed back to an operation control center to guide combustion optimization operation. According to the change of coal quality, the combustion process is adjusted in time, so that the high-efficiency combustion and low-pollution operation of the fire coal are realized, and the method has very important significance for improving the energy utilization efficiency and reducing the pollution of the fire coal.
Disclosure of Invention
In order to solve the problems, the utility model provides a device for measuring the fineness of coal powder by diffraction scattering.
The technical scheme of the utility model is as follows: a device for measuring the fineness of pulverized coal by diffraction scattering comprises a laser emission and beam expansion unit, a photoelectric detection and processing unit and a primary air pipe; the laser emitting and beam expanding unit and the photoelectric detection and processing unit are symmetrically positioned at two sides of the primary air pipe;
the laser emission and beam expansion unit comprises a He-Ne laser, a spatial filter and a beam expansion lens, wherein the spatial filter is connected with the He-Ne laser, and the center of the beam expansion lens is collinear with the center of the spatial filter;
the photoelectric detection and processing unit comprises a receiving lens, a photoelectric detector, a USB data acquisition unit and a PC (personal computer), wherein the photoelectric detector is connected with the USB data acquisition unit through a data line, the USB data acquisition unit is connected with the PC through a data line, and the center of the receiving lens is collinear with the center of the photoelectric detector;
the primary air pipe is positioned in the middle between the beam expanding lens and the receiving lens, and a certain straight section of the primary air pipe is used as a testing section.
Preferably, the spatial filtering center coincides with the focus of the beam expanding lens.
Preferably, the center of the photodetector coincides with the focal point of the receiving lens, and the photodetector is located on the focal plane of the receiving lens.
Preferably, the spatial filtering center, the focus of the beam expanding lens, the focus of the receiving lens, the center of the primary air pipe testing section and the center of the photoelectric detector are collinear.
Preferably, a connecting line of the focuses of the beam expanding lens and the receiving lens is coplanar and perpendicular to a central axis of the primary air pipe.
Preferably, the photodetector is annular.
Preferably, the beam expanding lens and the receiving lens are convex lenses.
Preferably, the testing section of the primary air pipe is subjected to lens treatment.
The beneficial technical effects of the utility model are as follows: a device for measuring the fineness of coal powder by diffraction scattering comprises a He-Ne laser, a spatial filter, a beam expanding lens, a primary air pipe, a receiving lens, a photoelectric detector, a USB data acquisition unit and a PC. A laser beam from a He-Ne laser is enhanced and stabilized through spatial filtering, after being expanded by a beam expanding lens, the laser beam is vertically irradiated on a coal powder particle group to be detected in a primary air pipe in parallel, generated diffraction light is converged by a focusing lens to form a diffraction pattern on a focal plane of the focusing lens, a photoelectric detector on the focal plane can perform photoelectric conversion on signals, USB data is collected and then sent to a PC, the size distribution of the coal powder particles can be quickly deduced back by adopting a pre-programmed formula and program, and the fineness of the coal powder is further calculated. Need not the sample, the buggy granule is to the pollution of air when preventing to take a sample, easy operation, convenient and fast can realize online real-time measurement, simple structure moreover, and it is convenient to maintain.
Drawings
Fig. 1 is a perspective view of a device for measuring the fineness of pulverized coal by diffraction and scattering according to the present invention.
Fig. 2 is a front view of an apparatus for diffraction-scattering measurement of fineness of pulverized coal according to the present invention.
Fig. 3 is a perspective view of the primary air duct.
Fig. 4 is a bottom view of the primary air duct.
Fig. 5 is a perspective view of the photodetector.
Fig. 6 is a front view of the beam expanding lens and the receiving lens.
Fig. 7 is a left side view of the beam expanding lens and the receiving lens.
Fig. 8 is a schematic diagram of an apparatus for diffraction-scattering measurement of coal fines fineness according to the present invention.
Fig. 9 is a schematic simplified diagram of a device for measuring the fineness of coal powder by diffraction and scattering according to the utility model.
In the figure: 1. He-Ne laser, 2 spatial filtering, 3 beam expanding lens, 31 laser,
4. The device comprises a primary air pipe, 41 primary air pipe testing sections, 5 receiving lenses, 6 photoelectric detectors, 61 diffraction patterns, 7 USB data acquisition, 71 data lines, 8 PC, 9 pulverized coal airflow, 10 laser emitting and beam expanding units and 11 photoelectric detection and processing units.
Detailed Description
Referring to fig. 1-9, a device for measuring the fineness of coal powder by diffraction and scattering, which is used for directly detecting the fineness of coal powder by laser diffraction, comprises a laser emitting and beam expanding unit, a photoelectric detection and processing unit and a primary air pipe; the laser emitting and beam expanding unit and the photoelectric detection and processing unit are symmetrically positioned at two sides of the primary air pipe; the laser emission and beam expansion unit comprises a He-Ne laser, a spatial filter and a beam expansion lens, wherein the He-Ne laser is used for emitting laser, the spatial filter is used for stabilizing and enhancing the laser, the beam expansion lens is used for diverging the laser, the spatial filter is connected with the He-Ne laser, and the center of the beam expansion lens is collinear with the center of the spatial filter; the photoelectric detection and processing unit comprises a receiving lens, a photoelectric detector, a USB data acquisition unit and a PC (personal computer), wherein the receiving lens is used for focusing and imaging to form a diffraction pattern, the photoelectric detector is used for receiving the diffraction pattern and carrying out photoelectric signal conversion, the USB data acquisition unit is used for collecting and integrating information, the PC is used for final processing, the photoelectric detector is connected with the USB data acquisition unit through a data line, the USB data acquisition unit is connected with the PC through a data line, and the center of the receiving lens is collinear with the center of the photoelectric detector; the primary air pipe is positioned in the middle between the beam expanding lens and the receiving lens, and a certain straight section of the primary air pipe is used as a testing section.
The center of the spatial filtering coincides with the focus of the beam expanding lens, and laser leaves from the spatial filtering and then directly enters the focus of the beam expanding lens, so that the best divergence effect is obtained.
The center of the photoelectric detector coincides with the focal point of the receiving lens, the photoelectric detector is positioned on the focal plane of the receiving lens, and the diffraction pattern received by the photoelectric detector is clearest.
The spatial filtering center, the focus of the beam expanding lens, the focus of the receiving lens, the center of the primary air pipe testing section and the center of the photoelectric detector are collinear.
The connecting line of the focuses of the beam expanding lens and the receiving lens is perpendicular to and coplanar with the central axis of the primary air pipe.
The photoelectric detector is annular and matched with an annular diffraction pattern formed on a focal plane of the receiving lens after diffraction light generated by the pulverized coal particle group is converged by the receiving lens.
The beam expanding lens and the receiving lens are convex lenses.
The testing section of the primary air pipe is subjected to lens treatment, the treated primary air pipe is equal to a concave lens, and the laser can penetrate through the primary air pipe to the maximum extent and is diffused, so that the pulverized coal particle group is optimally irradiated.
The working method comprises the following steps: referring to fig. 1-9, a laser emitting and beam expanding unit and a photoelectric detection and processing unit are installed at a certain section of a primary air pipe for directly blowing pulverized coal, and the device for intelligently measuring the fineness of the pulverized coal is installed; opening a He-Ne laser, stabilizing and enhancing the emitted laser through spatial filtering, separating the laser from the spatial filtering, expanding the laser through a beam expanding lens, vertically injecting the laser into a primary air pipe, irradiating the laser on a detected coal dust particle group, and generating diffracted light by the coal dust particle group; diffraction light generated by the pulverized coal particle group is converged by the receiving lens to form an annular diffraction pattern on a focal plane of the receiving lens, and after the diffraction pattern is received by an annular photoelectric detector positioned on the focal plane of the receiving lens, the photoelectric detector performs photoelectric conversion of signals, namely signal amplification and A/D conversion; the signals after photoelectric conversion enter a USB data acquisition device, the data acquisition device is sent into a PC, the size distribution of the pulverized coal particles can be quickly deduced reversely by adopting a pre-programmed formula and an optimization program, and the fineness of the pulverized coal is further calculated.
The coal powder fineness calculation formula is measured (arranged in a PC):
supposing that n particles are sampled, the diameter of each particle is Di, and the diameters of the particles with the diameters larger than 90 mu m are D1, D2 and D3 … Dj, the fineness R90 of the coal powder is calculated by the following formula:
similarly, the calculation formula of the coal powder fineness R200 is as follows:
according to the calculation, if Rx (namely the proportion of the particle size of the test coal powder larger than x mum) is measured, x is input into the controller, and the corresponding coal powder fineness Rx can be measured.
Secondly, calculating the coal powder uniformity index: index reflecting the particle size distribution of the coal fines, denoted by n:
similarly, the indexes of the distribution of the coal powder particle size of more than 90 μm and 200 μm are calculated, so that:
the utility model can measure the fineness of all coal dust particles in a sample, and the traditional sieving instrument needs various standard sieves with different apertures, can display various particle size distributions by programming and has better guiding function on the operation of a combustion and powder-making system. In addition, the particle size distribution provides certain reference significance for the research on coal quality, coal blending and the like.
Claims (8)
1. The utility model provides a device of diffraction scattering measurement buggy fineness which characterized by: the device comprises a laser emitting and beam expanding unit, a photoelectric detection and processing unit and a primary air pipe; the laser emitting and beam expanding unit and the photoelectric detection and processing unit are symmetrically positioned at two sides of the primary air pipe;
the laser emission and beam expansion unit comprises a He-Ne laser, a spatial filter and a beam expansion lens, wherein the spatial filter is connected with the He-Ne laser, and the center of the beam expansion lens is collinear with the center of the spatial filter;
the photoelectric detection and processing unit comprises a receiving lens, a photoelectric detector, a USB data acquisition unit and a PC (personal computer), wherein the photoelectric detector is connected with the USB data acquisition unit through a data line, the USB data acquisition unit is connected with the PC through a data line, and the center of the receiving lens is collinear with the center of the photoelectric detector;
the primary air pipe is positioned in the middle between the beam expanding lens and the receiving lens, and a certain straight section of the primary air pipe is used as a testing section.
2. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: the spatial filtering center coincides with the focus of the beam expanding lens.
3. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: the center of the photoelectric detector coincides with the focal point of the receiving lens, and the photoelectric detector is positioned on the focal plane of the receiving lens.
4. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: and the spatial filtering center, the focus of the beam expanding lens, the focus of the receiving lens, the center of the primary air pipe testing section and the center of the photoelectric detector are collinear.
5. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: and a connecting line of the focuses of the beam expanding lens and the receiving lens is coplanar and vertical to the central axis of the primary air pipe.
6. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: the photoelectric detector is annular.
7. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: the beam expanding lens and the receiving lens are convex lenses.
8. The device for diffraction scattering measurement of coal fines fineness of claim 1, characterized by: and the testing section of the primary air pipe is subjected to lens treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121430056.2U CN215953293U (en) | 2021-06-26 | 2021-06-26 | Device for measuring fineness of pulverized coal by diffraction scattering |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121430056.2U CN215953293U (en) | 2021-06-26 | 2021-06-26 | Device for measuring fineness of pulverized coal by diffraction scattering |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215953293U true CN215953293U (en) | 2022-03-04 |
Family
ID=80565935
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121430056.2U Expired - Fee Related CN215953293U (en) | 2021-06-26 | 2021-06-26 | Device for measuring fineness of pulverized coal by diffraction scattering |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215953293U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115144308A (en) * | 2022-05-24 | 2022-10-04 | 华南理工大学 | Device and method for measuring average particle size of pulverized coal |
-
2021
- 2021-06-26 CN CN202121430056.2U patent/CN215953293U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115144308A (en) * | 2022-05-24 | 2022-10-04 | 华南理工大学 | Device and method for measuring average particle size of pulverized coal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203949849U (en) | A kind of pick-up unit of measuring particle quality concentration | |
| CN104914024B (en) | It is applied to the particulate matter quality concentration detection apparatus and its method of suspended particulate substance in air | |
| CN101008604A (en) | On-line testing method for aerosol particles concentration and size and testing device thereof | |
| CN104122180A (en) | Method for measuring mass concentration of particulate matter | |
| CN104807738A (en) | Device for detecting shapes of single aerosol particles in real time | |
| CN215953293U (en) | Device for measuring fineness of pulverized coal by diffraction scattering | |
| CN105092445B (en) | A kind of on-Line Monitor Device and its method of PM2.5 industrial smokes | |
| CN103792100B (en) | A kind of method and apparatus determining separator | |
| CN109813639A (en) | A kind of particulate matter based on infrared light modulation techniques and gas concentration synchronous measuring apparatus and its measurement method | |
| Holve et al. | Optical particle counting, sizing, and velocimetry using intensity deconvolution | |
| CN105135897B (en) | A kind of PM2.5 flue gas flow fields self-adjusting system and its method | |
| CN108318389A (en) | A kind of novel particle concentration detection method | |
| CN205607812U (en) | Particle size detection device | |
| CN208270376U (en) | A kind of granularity on-line monitoring system | |
| Han et al. | An improved on-line measurement method of particulate matter concentration using tri-wavelength laser light scattering | |
| CN105203436A (en) | Granularity detection method | |
| Holve et al. | Design criteria and recent developments of optical single particle counters for fossil fuel systems | |
| Chen et al. | An image auxiliary method for laser-induced breakdown spectroscopy analysis of coal particle flow | |
| CN110702568B (en) | Laser-induced glow micron-sized carbon-containing particle mass concentration measuring device and method | |
| CN106568693B (en) | Particle size detection device based on light pulsation | |
| Huang et al. | On-line measurement of ultralow mass concentration particulate based on light scattering coupled with beta ray attenuation method | |
| CN115144308A (en) | Device and method for measuring average particle size of pulverized coal | |
| CN205015250U (en) | Particle size detection device | |
| CN113551946A (en) | Device and method for intelligently measuring fineness of pulverized coal | |
| CN205157388U (en) | Particulate matter on -line monitoring system based on beta penetrates line method and light scattering method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20220304 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |