CN202351152U

CN202351152U - Particle size distribution and shape distribution measuring device of granular material in pneumatic conveying pipeline

Info

Publication number: CN202351152U
Application number: CN2011205202641U
Authority: CN
Inventors: 闫勇; 高凌君; 卢钢
Original assignee: North China Electric Power University
Current assignee: North China Electric Power University
Priority date: 2011-12-14
Filing date: 2011-12-14
Publication date: 2012-07-25
Anticipated expiration: 2021-12-14

Abstract

The utility model discloses a particle size distribution and shape distribution measuring device of a granular material in a pneumatic conveying pipeline, which belongs to the scope of gas-solid two phase flow online measurement equipment. Three red green blue (RGB) laser light pieces with different spectra, an RGB digital camera and a telecentric lens form a particle flow imaging and image acquisition device. A laser control module is connected with three lasers with different spectra. The image acquisition device, the RGB digital camera and the telecentric lens form an imaging system of a particle flow field installed on a to-be-measured gas-solid two phase flow pipeline. An optical axis of the RGB digital camera is perpendicular to RGB three-color sheet laser beams emitted by the three lasers with different spectra. The output end of the RGB digital camera is connected with an image processing system. The particle size distribution and shape distribution measuring device of the granular material in the pneumatic conveying pipeline achieves simultaneous imaging on a plurality of focusing surfaces, utilizes exposure time of a laser pulse feedback control camera to achieve imaging of flowing particles, greatly reduces decree of complexity of the measuring device and improves measuring efficiency.

Description

Particulate material size-grade distribution and distribution of shapes measurement mechanism in a kind of airflow pipeline

Technical field

The utility model belongs to Dual-Phrase Distribution of Gas olid in-situ measurement equipment scope, particulate material size-grade distribution and distribution of shapes measurement mechanism in particularly a kind of airflow pipeline.

Background technology

Strength is carried and is widely used in the pellet of various industrial sectors, the conveying and the drying process of powder.An exemplary is the pipeline transportation of solid fuel such as coal dust etc. in the fuel-burning power plant.The coal dust that comes out from coal pulverizer is carried by pressurized air supplies with many conveyance conduits simultaneously, gets into the burner array then in the burner hearth internal combustion.The distribution of pulverized coal particle granularity and the efficient of burning and pollutant discharge amount have close getting in touch.Yet the serviceability of coal pulverizer and the physical characteristics of coal etc. are depended in the distribution of pulverized coal particle granularity.In recent years, the coal-burning power plant of countries in the world begins to adopt coal dust and living beings burning technology altogether, to reduce emission of carbon-dioxide.Many power plant all adopt generating power with biomass combustion.Many living beings such as stalk etc. are bigger than pulverized coal particle, and are irregularly shaped, so biomass combustion or coal dust and living beings are burnt altogether with pure coal dust firing and are very different.The burning of bulky grain and irregular fuel particle can directly have influence on the discharge capacity of burning efficiency and pollutant.Fuel granularity is excessive or cross detailed rules and regulations and can cause incomplete combustion or the increase of coal pulverizer energy consumption etc., can cause line clogging when serious, by forced-stopping machine, causes heavy losses to power plant.Therefore, the particle size distribution and the distribution of shapes of power plant's coal dust and living beings are carried out the on-line continuous detection, help to improve the security and the burning efficiency of boiler combustion, reduce pollutant emission.

Existing particle sizing imaging device is general to adopt cross section, a flow field in the single laser illumination pipeline, so can only obtain a width of cloth particle image.As go for the size-grade distribution and the distribution of shapes of particle in the whole pipe, can adopt the particle illuminating device and complicated optical module of scan-type on the principle.Yet such design cost is high, and system complex and efficient are low, and poor reliability is difficult to safeguard.The present invention utilizes the differentiable characteristic of RGB digital camera R (redness) G (green) B (blueness) picture signal; Shine the particle flow field simultaneously through RGB three look pulse laser sheet lasers; The image of flow particles on the cross section, three flow fields that utilizes RGB digital camera and telecentric mirror head to absorb simultaneously to be illuminated; Greatly reduce the complicacy of device, improved efficiency of measurement and reliability.The present invention is not only applicable to the continuous on-line monitoring of pulverized coal particle stream in the fuel-burning power plant, is applicable to the on-line monitoring of industrial process of pneumatic transmission such as food, cement, iron and steel yet.

The utility model content

The purpose of the utility model is to adopt cross section, a flow field in the single laser illumination pipeline to existing particle sizing imaging device is general, so can only obtain a width of cloth particle image.As go for the size-grade distribution and the distribution of shapes of particle in the whole pipe, can adopt the particle illuminating device and complicated optical module of scan-type on the principle.Yet; Such design cost is high; System complex and efficient are low, poor reliability, the deficiency that is difficult to safeguard and particulate material size-grade distribution and distribution of shapes measurement mechanism in a kind of airflow pipeline are provided; It is characterized in that, constitute grain flow imaging and image collecting device by three RGB laser mating plates with different spectrum, RGB digital camera and telecentric mirror head; The laser instrument control module connects with the laser instrument of three different spectrum; Image collecting device, RGB digital camera and telecentric mirror head are formed the imaging system in particle flow field, and are installed on the optical axis of RGB digital camera on the tested Dual-Phrase Distribution of Gas olid body pipeline and the angle beta between the RGB laser mating plate is chosen for 90 °; It is vertical that the optical axis of RGB digital camera and the laser instrument of three different spectrum are that red R laser instrument, green G laser instrument and blue B laser instrument send RGB three color chips shape laser beam; The output of RGB digital camera connects image processing system.

Three laser sheets of said RGB laser mating plate should be arranged in parallel, and the distance between adjacent two laser mating plates is chosen between 10 to 15 times of maximum particle diameter of tested particle.

Said RGB laser mating plate three laser sheet thickness should be in 0.5 to 1.5 times of scope of the maximum particle diameter of survey particle;

Angle [alpha] between said RGB laser mating plate and the pipeline center's axle should be in 45 ° to 60 ° scope.

The beneficial effect of the utility model is under the situation that only adopts a RGB camera; Each frame RGB picture breakdown is become and three pairing R of laser spectrum (redness); G (green) and B (blueness) three width of cloth subimages, thus the image of particle on the cross section, three flow fields obtained in the fluid line simultaneously.Three width of cloth solid particle images are carried out Space Reconstruction, obtain the space distribution of solid particle in tested zone, flow field.Three width of cloth subimages are carried out Treatment Analysis, thereby obtain the size-grade distribution and the distribution of shapes of particle.And greatly reduced requirement to camera, reduced cost.

Description of drawings

Fig. 1 is particulate material size-grade distribution and distribution of shapes on-line measurement apparatus structure and principle schematic.

Among the figure:

1, particle flow field, 2, RGB laser mating plate (RGB three color chips shape laser beam), 3, red (R) laser instrument; 4, green (G) laser instrument, 5, blue (B) laser instrument, 6, the RGB digital camera; 7, telecentric mirror head, 8, the laser instrument control module, 9, image processing system 10, Dual-Phrase Distribution of Gas olid pipeline.Angle between α-laser array and the pipeline, angle between β-RGB digital camera and the pipeline, the distance between the d-laser instrument.

Embodiment

The utility model provides particulate material size-grade distribution and distribution of shapes measurement mechanism in a kind of airflow pipeline.Below in conjunction with Fig. 1 explaining to the utility model:

Constitute grain flow imaging and image collecting device by three RGB laser mating plates with different spectrum 2, RGB digital camera 6 and telecentric mirror head 7; Laser instrument control module 8 connects with promptly red (R) laser instrument 3 of the laser instrument of three different spectrum, green (G) laser instrument 4, blue (B) laser instrument 5; Image collecting device, RGB digital camera 6 and telecentric mirror head 7 are formed the imaging system in particle flow field 1, and are installed on the tested Dual-Phrase Distribution of Gas olid body pipeline 10; The output of RGB digital camera 6 connects image processing system 9; Cover the purpose that complete particle does not have overlapping particle in order to reach in the laser sheet, the thickness of laser mating plate 2 sheet laser should be in 0.5 to 1.5 times of scope of the maximum particle diameter of survey particle.Three laser sheets should be arranged in parallel, and the distance between adjacent two laser sheets is chosen between 10 to 15 times of maximum particle diameter of tested particle.Angle beta between the optical axis of RGB digital camera 6 and the laser mating plate 2 is chosen for 90 °.Angle [alpha] between laser mating plate 2 and the pipeline center's axle should be in 45 ° to 60 ° scope.

RGB camera 6 formed images when realizing the digital imagery of flow particles and adopting telecentric mirror head (telecentric lens) 7 to realize on a plurality of focusing surfaces in the time shutter (not being to use the shutter of camera) of laser instrument control module 8 control cameras; Thereby collect the RGB image in particle flow field 1 of the solid particle in cross section, three different flow fields.The RGB picture signal in particle flow field 1 is imported image processing system 9 into by RGB camera 6 and is carried out Flame Image Process and data analysis, obtains and three pairing R of laser mating plate, G and B three width of cloth particle subimages.To three width of cloth images respectively Treatment Analysis can obtain particle size distribution and distribution of shapes on three cross sections of pipeline, and show through user interface of software.In real-time monitoring system, the granularity of particle and distribution of shapes information are presented in the user interface, with the output of the statistical information of whole user interface, and according to the renewal result of the particle information that newly advances, thereby realize on-line real time monitoring.

Claims

1. particulate material size-grade distribution and distribution of shapes measurement mechanism in the airflow pipeline is characterized in that, constitute grain flow imaging and image collecting device by three RGB laser mating plates with different spectrum, RGB digital camera and telecentric mirror head; The laser instrument control module connects with the laser instrument of three different spectrum; Image collecting device, RGB digital camera and telecentric mirror head are formed the imaging system in particle flow field, and are installed on the tested Dual-Phrase Distribution of Gas olid body pipeline, and the angle beta between the optical axis of RGB digital camera and the RGB laser mating plate is chosen for 90 °; It is vertical that the optical axis of RGB digital camera and red R laser instrument, green G laser instrument and blue B laser instrument send RGB three color chips shape laser beam; The output of RGB digital camera connects image processing system.

2. according to particulate material size-grade distribution and distribution of shapes measurement mechanism in the said a kind of airflow pipeline of claim 1; It is characterized in that; Three laser sheets of said RGB laser mating plate should be arranged in parallel, and the distance between adjacent two laser mating plates is chosen between 10 to 15 times of maximum particle diameter of tested particle.

3. according to particulate material size-grade distribution and distribution of shapes measurement mechanism in the said a kind of airflow pipeline of claim 1, it is characterized in that, said RGB laser mating plate three laser sheet thickness should be in 0.5 to 1.5 times of scope of the maximum particle diameter of survey particle.

4. according to particulate material size-grade distribution and distribution of shapes measurement mechanism in the said a kind of airflow pipeline of claim 1, it is characterized in that the angle [alpha] between said RGB laser mating plate and the pipeline center's axle should be in 45 ° to 60 ° scope.