A visual system for intelligent dust analysis in confined spaces and its application

Abstract

The present invention relates to a dust intelligent analysis visual system for a confined space and its application. The system's purge and dust removal control monitors the amount of dust accumulation through an optical sensor, controls the opening of the gas source through an integrated circuit, and automatically implements compressed gas purge and dust removal; the purge and cooling control monitors the temperature through a temperature and humidity sensor, controls the opening of the gas path through an integrated circuit, and then automatically implements compressed gas purge and cooling through a cooling structure; the embedded video image analysis algorithm extracts the characteristic texture of the silo, fuzzy processes the image entropy, calculates the material level value of the dust silo, and performs error correction under the reference of the elevation line calibrated on the inner wall of the silo, and the material level value is output by the integrated circuit. The present invention is adopted to realize the detection of the material level through the video image algorithm, and the dust shielding of the lens is purged, cooled and cleaned through the self-contained cold light source or infrared camera mode, and the instrument uses compressed air to purge, cool and clean, which can meet the application requirements of industrial scenes with high temperature, high pressure, flying dust and no lighting.

Description

Technical Field

[0001] The invention relates to a dust intelligent analysis visualization system for a confined space and application thereof. Background Art

[0002] In the industrial production process, the operation monitoring of equipment generally adopts temperature, pressure, pressure difference, flow, material level, etc., and video monitoring is adopted in some important open places to assist. For example, bag operation adopts pressure difference and temperature, ash hopper monitoring adopts material level and temperature, powder silo monitoring adopts continuous material level and switch material level, boiler drum, equipment room and other open spaces adopt video monitoring to assist.

[0003] In the utility model patent No. ZL201721163761.4, a dust monitoring device for air is disclosed, including a base, a support tube, a support rod, a detection tube, a purification tube, a dust removal box and an exhaust tube, wherein the support tube is fixedly mounted on the base, a support rod is sleeved on the support tube, a first mounting rod is mounted on the upper end of the support rod, a detection tube is mounted on the right end of the first mounting rod, a collar is sleeved on the support tube, a second mounting rod is mounted on the right side of the collar, a purification tube is mounted on the right end of the second mounting rod, an anti-backflow plate is mounted on the inner side of the upper part of the purification tube, a dust removal box is arranged below the purification tube, a dust collection bag is arranged on the inner side of the dust removal box, and an exhaust tube is fixedly mounted on the bottom of the dust removal box. The utility model can monitor parameters such as dust in the air and purify the air, has strong practicality, and is mainly used for open environment monitoring.

[0004] In the patent application document of patent application number 201210458321.7, a closed space environment monitoring and control system is disclosed, which includes a processing unit, a sensing unit, a control unit, etc. The sensing unit includes a digital input module, a first A / D conversion module and a second A / D conversion module. The digital input module is connected to a water immersion alarm sensor and a smoke sensor through a wire. The first A / D conversion module is connected to an indoor temperature sensor and an indoor humidity sensor through a wire. The second A / D conversion module is connected to a sulfur hexafluoride sensor through a wire. The control unit includes a first digital output module and a second digital output module. The first digital output module is connected to an external air door drive module, an internal air door drive module, an outdoor unit drive module, a cold and hot mode conversion drive module, and a dehumidification drive module through a wire. It is characterized in that the first digital output module is also connected to a waste heat valve drive module through a wire. The use of this monitoring system can shorten the cooling and ventilation time, improve work efficiency, and extend the service life of electrical equipment. It is mainly suitable for monitoring humidity and temperature.

[0005] In the invention patent application with patent application number 201810346625.1, a fully enclosed coal bunker monitoring system device is disclosed, which is arranged in a fully enclosed coal yard. It consists of a monitoring device and an operating mechanism. The monitoring device consists of an explosion-proof integrated infrared scanning thermal imager, a temperature monitor, a dust monitor, a gas monitor, a PLC, a network transmitter, a power box, a wireless transceiver, a wireless transmission device, a master control computer, and an alarm device; the operating mechanism consists of a running track, wheels and their accessories, and an automatic charging device. The fully enclosed coal bunker monitoring system of the present invention performs real-time monitoring of gas, dust, temperature, etc. in the fully enclosed coal bunker. It collects data in the bunker. When it finds factors that may cause danger, it promptly activates the automatic alarm device, takes corresponding treatment measures, eliminates safety hazards, reduces the accident rate, and reduces the cost. Although this technology is suitable for confined spaces with a small amount of dust, it still needs to be further improved for working environments with a large amount of dust.

[0006] To sum up, in industrial production, the environment in enclosed spaces is harsh, with high temperature, high pressure, flying dust, and no lighting, which makes visual monitoring a challenge. Therefore, it is of great significance to provide intelligent devices including video monitoring, fire early warning, and material level detection for specific industrial scenarios based on video analysis technology. Summary of the invention

[0007] The purpose of the present invention is to provide a dust intelligent analysis visual system for a confined space and its application, which meets the application requirements of industrial scenes with high temperature, high pressure, flying dust and no lighting through video image algorithm detection, built-in cold light source or infrared camera mode, and purging and cooling methods.

[0008] The technical solution adopted by the present invention is: a visual system for intelligent dust analysis in a confined space and its application, characterized in that the system includes an air source, a monitoring device and a central control integrated circuit, and the monitoring methods include purging and dust removal control, purging and cooling control, an embedded video image analysis algorithm, an output industrial PLC control interface and an alarm interface; the purging and dust removal control is composed of an air source, a purging structure in the monitoring device, an optical sensor and a central control integrated circuit, the central control integrated circuit monitors the amount of dust accumulation through an optical sensor, controls the opening of the air source through the central control integrated circuit, and then automatically implements compressed gas purging through the purging structure to complete dust removal; the purging and cooling control is composed of an air source, a ... The equipment is composed of a cooling structure, a temperature and humidity sensor and a central control integrated circuit. The central control integrated circuit monitors the temperature through the temperature and humidity sensor, controls the gas path to open through the central control integrated circuit, and then automatically implements compressed gas purge through the cooling structure to complete the cooling. The embedded video image analysis algorithm extracts the characteristic texture of the silo, fuzzy processes the image entropy, calculates the material level value of the dust silo, and performs error correction under the reference of the elevation line calibrated on the inner wall of the silo. Finally, the central control integrated circuit outputs the material level value. The central control circuit also includes elevation line light control, various output interfaces of the material level value, modbus protocol, alarm parameter setting and alarm output relay control.

[0009] The intelligent dust analysis visual system for a confined space and its application are characterized in that its monitoring equipment includes a casing, a movement, an equipment room, a cooling protective gas inlet, a purge protective gas inlet, a mounting flange, a bell-mouth dust cover and a cooling protective gas spiral duct and an air outlet; the equipment room includes a spherical mirror and a camera, and is equipped with an optical sensor and a temperature and humidity sensor.

[0010] The intelligent dust analysis visual system for a confined space and its application are characterized in that the cooling protective gas spiral duct and the air outlet adopt a spiral structure, and the air outlet is proportionally distributed along the inner wall of the spiral to form a three-dimensional cross protection, and the pressure is maintained at 0.06-0.1MPa.

[0011] The intelligent dust analysis visual system for a confined space and its application are characterized in that the purge air outlets are distributed in a ring shape around the equipment room and are combined with a bell-mouth dust cover to achieve the cleaning purpose by utilizing the rapid expansion of compressed air, and the pressure is maintained at 0.3-0.6MPa.

[0012] By adopting the present invention, high-definition image monitoring is realized by opening holes in the side walls or tops of dust-sealed tanks such as powder silos and ash hoppers and installing flanges, material level detection is realized by video image algorithms, dust obstructions on the lens are purged, cooled and cleaned by means of a built-in cold light source or infrared camera mode, and compressed air is used for the instrument, and focusing and dust-proof requirements are achieved by means of a dust-proof sealing cover, and application requirements of industrial scenes with high temperature, high pressure, flying dust and no lighting are met. At the same time, the present invention also has an image output function for superimposing text on video image output and material level detection results, as well as a variety of material level and risk percentage detection output interfaces, and control and alarm input and output interfaces for industrial control, and complies with the MODBUS protocol and can be directly connected to a PLC controller or a DCS system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the monitoring device of the present invention.

[0014] Figure 2 It is a schematic diagram of the monitoring device of the present invention installed at a corner.

[0015] Figure 3 This is the intention of the monitoring device of the present invention to be installed on the top surface.

[0016] Figure 4 It is a schematic diagram of the monitoring device of the present invention being installed on an inclined surface.

[0017] Figure 5 It is a schematic diagram of the monitoring device of the present invention installed on a vertical plane.

[0018] Figure 6 It is a schematic diagram of the gas source circuit of the present invention.

[0019] Figure 7 It is a functional schematic diagram of the central control integrated circuit of the present invention.

[0020] The serial numbers in the figure indicate: casing 1, movement 2, equipment room 3, cooling protective gas inlet 4, purge protective gas inlet 5, mounting flange 6, bell-mouth dust cover 7, cooling protective gas spiral duct and outlet 8, cooling protective gas source 9 and purge protective gas source 10. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be fully described below in conjunction with the embodiments of the present invention. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] 1. Implementation

[0023] The visual system for intelligent dust analysis in a confined space includes an air source, a monitoring device and a central control integrated circuit. The monitoring methods include purge dust removal control, purge cooling control, an embedded video image analysis algorithm, an output industrial PLC control interface and an alarm interface. The purge dust removal control is composed of an air source, a purge structure in the monitoring device, an optical sensor and a central control integrated circuit. The central control integrated circuit monitors the amount of dust accumulation through an optical sensor, controls the opening of the air source through the central control integrated circuit, and then automatically implements compressed gas purge through the purge structure to complete dust removal. The purge cooling control is composed of an air source, a cooling structure in the monitoring device, a temperature and humidity sensor, and a central control integrated circuit. The central control integrated circuit monitors the temperature through the temperature and humidity sensor, controls the air path to open through the central control integrated circuit, and then automatically implements compressed gas purge through the cooling structure to complete the cooling; the embedded video image analysis algorithm extracts the characteristic texture of the silo, fuzzy processes the image entropy, calculates the material level value of the dust silo, and performs error correction under the reference of the elevation line calibrated on the inner wall of the silo, and finally the central control integrated circuit outputs the material level value; the central control circuit also includes elevation line light control, various output interfaces of the material level value, modbus protocol, alarm parameter setting and alarm output relay control.

[0024] The monitoring equipment mentioned above refers to Figure 1 As shown, the monitoring equipment includes a housing 1, a movement 2, an equipment room 3, a cooling structure, i.e., a cooling protective gas inlet 4, a purge structure, i.e., a purge protective gas inlet 5, a mounting flange 6, a bell-shaped dust cover 7, and a cooling protective gas spiral duct and an air outlet 8. The equipment room 3 includes a spherical mirror and a camera, and is provided with an optical sensor and a temperature and humidity sensor. The cooling protective gas spiral duct and the air outlet adopt a spiral structure, and the air outlet is proportionally distributed along the inner wall of the spiral to form a three-dimensional cross protection, and the pressure is maintained at 0.06-0.1MPa. The purge gas outlet is distributed in a ring shape around the equipment room, combined with the bell-shaped dust cover, and the rapid expansion of compressed air is used to achieve the cleaning purpose, and the pressure is maintained at 0.3-0.6MPa.

[0025] The gas source used by the above monitoring equipment is as follows: Figure 6 The gas source is connected by industrial instrument gas, which is divided into a cooling protection gas source 9 and a purging protection gas source 10. The cooling protection gas source 9 is connected to the cooling protection gas inlet 4, and the purging protection gas source 10 is connected to the purging protection gas inlet 5.

[0026] 2. Installation of the embodiment

[0027] Reference Figures 2 to 6 As shown, the following steps are included.

[0028] 1. Open a 65-350mm diameter round hole on the side wall or top wall of the closed space, insert the corresponding seamless steel pipe, flush with the inner wall, and reserve a 150-300mm welding flange on the outside as a monitoring window. The monitoring window can be horizontal, inclined, or vertical.

[0029] 2. The connection method of the monitoring equipment is to install flange 6. After the installation is completed, the closure of the enclosed space is restored, and its pressure level is equal to or higher than the original enclosed space requirements.

[0030] 3. The monitoring equipment uses a camera for all-round image acquisition, and the auxiliary light source is a cold light source or an infrared camera.

[0031] 4. The bell-mouth dust cover 7 in the monitoring equipment adopts a bell-mouth form, which is beneficial to the mirror protection of the camera and is convenient for purging; the wall is painted with reflective paint to enhance the reflection of light and facilitate focusing.

[0032] 5. The monitoring equipment is equipped with a cooling structure and a purge structure, namely, a cooling protective gas inlet 4 and a purge protective gas inlet 5, to prevent the camera mirror from being contaminated. Industrial sites are generally equipped with industrial gas, through a pressure reduction device, a cooling protective gas spiral duct and an air outlet 8 adopt a spiral structure, and the air outlet is proportionally distributed along the inner wall of the spiral to form a three-dimensional cross protection, generally at 0.06-0.1MPa; the purge gas outlet is distributed in a ring around the lens, combined with a bell-mouth dust cover, and the rapid expansion of compressed air is used to achieve the purpose of cleaning. Its pressure is generally 0.3-0.6MPa; in dust-proof and explosion-proof places, nitrogen or other inert gases can be used.

[0033] 6. According to specific needs, set up video baseband transmission, network transmission, optical fiber transmission, microwave transmission, twisted pair transmission, and access the industrial video surveillance system of the factory.

[0034] 7. The power supply of the monitoring equipment can be DC24V or AC220V, which is convenient for on-site access.

[0035] 2. Application of the embodiments

[0036] 1. Example 1: Ash storage and silo.

[0037] In industrial production, the material level monitoring of ash silos and silos uses radar level meters or heavy hammer level meters as continuous material level monitoring, and uses switch level meters such as radio frequency admittance, tuning fork or resistance rotation as auxiliary alarm control for high and low material levels. The above monitoring methods can only be partial. The powder in the ash silo and silo will cause measurement deviation or false signal due to humidity and temperature changes, resulting in hardening and wall hanging.

[0038] By installing the above-mentioned intelligent visual monitoring equipment on the top of the ash silo or material silo or on the side wall near the top, the internal conditions of the ash silo and material silo can be visually monitored to provide accurate and intuitive information.

[0039] In the ash silo, the inside of the silo can be assisted by brushing a ruler or sticking reflective materials, so that the material level of the silo is clear at a glance. At the same time, the microcomputer processor outputs a standard signal of 0-5V or 4-20mA.

[0040] When the dust in the ash silo or material bin sticks to the camera protection cover, the microcomputer processor issues a purge command through the calculation of dust transmittance, and the purge dust removal control unit works, using high-pressure compressed air to purge the camera protection cover. When the powder in the ash silo or material bin becomes hardened or hangs on the wall due to humidity and temperature changes, the microcomputer processor sends an alarm signal through the AI ​​intelligent recognition system, and the purge and cooling control unit starts working. In this way, the monitoring equipment can clearly receive the scale image, use the triangulation principle for calculation, measure the material level height, or directly read the scale characteristic value to directly read the height value, without causing deviation or false signal.

[0041] 2. Example 2: Semi-dry valve at the inlet elbow of the desulfurization tower.

[0042] In actual operation, the monitoring of the desulfurization tower inlet elbow in semi-dry desulfurization adopts pressure difference means, and the signal is delayed; the tower bottom ash discharge is usually used to prevent and solve the ash accumulation phenomenon at the bottom of the tower. This place is in the main flue, without bypass, and is a closed space with high-temperature flue gas inside, which is difficult to repair online. When problems are found, it often affects production.

[0043] Installing intelligent visual monitoring equipment on the top of the elbow can directly monitor the internal situation of the elbow. When ash blocks fall from the Venturi and there is dust accumulation at the elbow, the image features are obvious. The structural pattern recognition can directly determine the operating status. The microcomputer processor issues an alarm command in time through the AI ​​intelligent recognition system, and predicts the working condition in advance when the pressure difference method has not yet been reflected, providing reliable information for the safe operation of the desulfurization tower. When dust sticks to the camera protective cover; through the calculation of the dust transmittance, the microcomputer processor issues a purge command, and the purge dust control unit works, using high-pressure compressed air to purge the camera protective cover.

[0044] 3. Example 3: ash hopper, cloth bag.

[0045] When the boiler burns poorly, the smoke dust carries fire and accumulates on the ash hopper and bags, which poses a risk of reignition. In February 2020, the ship-shaped hopper of the Gaoyou Biomass Power Plant reignited the ash inside the ash hopper, causing great losses. Fortunately, it was discovered in time and no fire occurred.

[0046] Installing intelligent visual monitoring equipment on the upper part of the ash hopper can visually monitor the internal conditions of the ash hopper and the bag, using the characteristic values ​​under normal working conditions as a benchmark, and using infrared camera mode. When local high temperature appears inside, the working condition can be predicted in time, and the purge and cooling control unit starts working, providing reliable guarantee for the safe operation of the ash hopper and the bag.

[0047] At the same time, the ash level in the ash hopper is monitored, and the internal situation of the ash hopper can be monitored intuitively. When the ash inside the ash hopper becomes hardened due to humidity and temperature changes, and there is dust accumulation in the ash hopper, the microcomputer processor will issue an alarm command in time through the AI ​​intelligent recognition system to provide reliable information for the safe operation of the ash hopper. When dust sticks to the camera protective cover; through the calculation of the dust transmittance, the microcomputer processor issues a purge command, and the purge dust control unit works, using high-pressure compressed air to purge the camera protective cover.

[0048] When the furnace is shut down for maintenance, it can replace manual entry to check the bag condition.

[0049] 4. Example 4: Dry desulfurization with a ship-shaped bucket, a small ash chute, and a small ash hopper.

[0050] In semi-dry desulfurization, the ship-shaped bucket and the ash chute are the key parts of the desulfurization ash return system and are also the difficult points to control. The ship-shaped bucket is generally equipped with a glass observation hole, a continuous material level meter, a high, medium and low material level meter to observe the ash level, and the ash chute and ash hopper are equipped with a thermometer to determine whether the ash hopper is ash-accumulated.

[0051] Intelligent visual monitoring equipment is installed in the ship-shaped hopper and the small ash hopper to visually monitor the internal conditions. Based on the characteristic values ​​under normal operation, the combination of structural pattern recognition and fuzzy pattern recognition is used to observe whether the ash under the small chute is smooth and the ash level of the ship-shaped hopper and the small ash hopper. When an abnormal situation occurs, the microcomputer processor can quickly report the working conditions, providing reliable guarantee for its safe operation.

[0052] When dust sticks to the camera protection cover, the microcomputer processor calculates the dust transmittance, issues a purge command, and the purge dust removal control unit operates to purge the camera protection cover with high-pressure compressed air.

[0053] At the same time, when the furnace is shut down for maintenance, it can replace manual entry to check the working condition of the fluidized bed.

[0054] 5. Example 5: Others

[0055] The intelligent analysis and visualization device for dust-enclosed spaces is widely used and is suitable for working conditions in dust-enclosed spaces in industrial and civil production.

Claims

1. A visual system for intelligent dust analysis in a confined space, characterized in that The system includes an air source, a monitoring device and a central control integrated circuit. The monitoring methods include purge dust removal control, purge cooling control, an embedded video image analysis algorithm, an output industrial PLC control interface and an alarm interface. The purge dust removal control is composed of an air source, a purge structure in the monitoring device, an optical sensor and a central control integrated circuit. The central control integrated circuit monitors the amount of dust accumulation through an optical sensor, controls the opening of the air source through the central control integrated circuit, and then automatically implements compressed gas purge through the purge structure to complete dust removal. The purge cooling control is composed of an air source, a cooling structure in the monitoring device, a temperature and humidity sensor and a central control integrated circuit. The central control integrated circuit monitors the temperature through the temperature and humidity sensor, controls the gas path to open through the central control integrated circuit, and then automatically implements compressed gas purge through the cooling structure to complete the cooling; the embedded video image analysis algorithm extracts the characteristic texture of the silo, fuzzy processes the image entropy, calculates the material level value of the dust silo, and performs error correction under the reference of the elevation line calibrated on the inner wall of the silo, and finally the central control integrated circuit outputs the material level value; the central control integrated circuit also includes elevation line light control, various output interfaces of the material level value, modbus protocol, alarm parameter setting and alarm output relay control.

2. According to claim 1, a dust intelligent analysis visual system for a confined space is characterized in that The monitoring equipment includes a shell, a movement, an equipment room, a cooling protective gas inlet, a purge protective gas inlet, a mounting flange, a bell-mouth dust cover, and a cooling protective gas spiral duct and an air outlet. The equipment room includes a spherical mirror and a camera, and is equipped with an optical sensor and a temperature and humidity sensor.

3. According to claim 1, a dust intelligent analysis visual system for a confined space is characterized in that The cooling protective gas spiral duct and air outlet adopt a spiral structure, and the air outlet is proportionally distributed along the inner wall of the spiral to form a three-dimensional cross protection, and the pressure is maintained at 0.06 ~ 0.1MPa.

4. The dust intelligent analysis visual system for a confined space according to claim 1 is characterized in that The purge gas outlet is distributed in a ring shape around the equipment room and combined with the bell-mouth dust cover to achieve the cleaning purpose by using the rapid expansion of compressed air. The pressure is maintained at 0.3-0.6MPa.

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