Rapid detection system for ash content of coal slurry

Abstract

The invention relates to the technical field of coal slurry flotation, and provides a coal slurry ash content rapid detection system which comprises a coal slurry sampling, caching and quantitative feeding mechanism, a coal slurry dewatering and dewatering product pulping and discharging mechanism, a water and ash detection mechanism and an electric control mechanism. The coal slurry is subjected to rapid dehydration and shaping, the moisture of a filter cake is detected through microwaves, good conditions can be better provided for ash content detection, the situation that the moisture generates a dilution effect, a scattering effect and the like on ash content detection is avoided, and therefore the accuracy of ash content detection is improved, the limit detection error of the system for flotation feeding and flotation concentrate coal slurry ash content is small, and the effect is good; meanwhile, coal slurry ash content at different time can correspond to flotation process parameters by adopting a database, remote display can be realized, the labor intensity of workers can be reduced in cooperation with a flotation intelligent control system, flotation effect fluctuation is reduced, the flotation effect is improved, and the flotation efficiency is improved. The influence of the coal slurry concentration or the material granularity change in the coal slurry on the ash content detection result in the prior art is solved.

Description

Technical Field

[0001] This invention relates to the field of coal slime flotation technology, and more specifically, to a rapid detection system for coal slurry ash content. Background Technology

[0002] Flotation is currently the most effective method for separating coal slime, but its process is influenced by numerous factors, such as the concentration of the coal slurry in the flotation feed, the amount of dry coal slime, the particle size distribution, density composition, degree of metamorphism, type and distribution of impurity minerals, the content of high-ash fine mud in the water, and the residual reagent dosage, etc. Furthermore, the influence of these factors on different types of coal slime varies significantly, and there is currently no universally applicable process model for flotation. Therefore, to achieve intelligent control of the flotation process, relying solely on feedforward adjustment is often insufficient. It is necessary to implement feedback adjustments based on the product indicators of the flotation process to ensure the stability of the flotation process, the pass rate of the indicators, and simultaneously reduce reagent consumption and the labor intensity of personnel.

[0003] The most important product indicator in the flotation process is the ash content of the flotation concentrate and tailings. However, these materials are often dewatered products from pressure filtration, filtration, or centrifugation during coal preparation. The time required from the completion of dewatering of the flotation product coal slurry is relatively long. If ash content testing is performed on the dewatered products during this process, the results will undoubtedly be significantly delayed. Furthermore, the buffer period before dewatering makes it even more difficult to correlate the measured ash content with different time points in the flotation process. Therefore, flotation production urgently needs a rapid ash content detection system or device for the product coal slurry. This can also lead to rapid detection of ash content in the flotation feed coal slurry, further enhancing the accuracy of feedforward adjustment in the intelligent control of the flotation process.

[0004] Currently, existing rapid coal slurry ash content detection technologies can be mainly divided into two categories: one is to directly detect the dewatering products after coal slurry dewatering; the other is to directly detect the ash content of coal slurry without any coal slurry pretreatment. However, in existing technologies, the first type of method often suffers from interference, scattering, and "dilution" of ash content due to moisture in the dewatering products. This problem is currently mainly suppressed by methods such as sufficient dewatering time and controlling moisture deviation, but practical experience shows that the results are generally poor. In addition to this problem, this type of method also suffers from intermittent detection, large fluctuations in test results, and high production consumption. The second type of method is greatly affected by the coal slurry concentration and the particle size of solids in the coal slurry. Although the coal slurry concentration can be accurately measured online, there is currently no accurate online detection method for the particle size distribution of solids in the coal slurry. Therefore, the second type of method, which directly detects coal slurry ash content without pretreatment, currently has no successful application cases. Summary of the Invention

[0005] To overcome the above-mentioned defects, embodiments of the present invention provide a rapid coal slurry ash content detection system, which avoids the influence of existing technologies on ash content detection results due to changes in coal slurry concentration or particle size of materials in the coal slurry.

[0006] According to one aspect, at least one embodiment of the present invention provides a rapid coal slurry ash content detection system, comprising: The gravity-flow sampling tube, which may be one or more tubes, is used for coal slurry sampling; A buffer mixing tank is used to buffer samples taken by the gravity sampling tube. A fabric funnel, the fabric funnel being used for fabric; A metering pump is used to feed the material in the buffer mixing tank into the cloth funnel in a specific direction; Coal slurry dewatering machine, the coal slurry dewatering machine is used for dewatering coal slurry after it is fed by the feeding mechanism; A pulping and mixing tank, wherein the pulping and mixing tank is used for pulping and discharging dewatered products; A microwave moisture meter, an ash meter, and a water-ash meter traveling device and a dust removal device for controlling the moisture meter and the ash meter.

[0007] As a further technical solution, the coal slurry sampled by the gravity sampling pipe is sampled by the squeeze valve to control the sampling amount, and the sampling pipeline is switched by the solenoid valve. The number of sampling pipelines is consistent with the number of sampling channels, and it is set at the bottom of the pipeline to be sampled or the gentle slope section of the chute. The coal slurry buffer tank is equipped with a coal slurry agitator and a defoamer inside, which are used to buffer the sampled coal slurry. The buffering time for a single channel is about 1 to 3 minutes.

[0008] As a further technical solution, quantitative feeding is carried out using a single screw pump and fed to the coal slurry dewatering machine through a feeding funnel; The feeding hopper can reciprocate along the length of the coal slurry dewatering machine, while the outlet pipeline of the quantitative feed pump reciprocates along the width of the feeder.

[0009] As a further technical solution, the coal slurry dewatering machine includes: a rubber belt, a filter belt, a vacuum box, a gas-water separator, a vacuum pump, a filter cake width limiting and pressing block, a filter cake shaping roller, a vacuum box stroke sensor, a filter cake weighing device, a filter belt washing box, a discharge device, and a dust removal fan.

[0010] As a further technical solution, the cross-section of the rubber belt is a flat belt, and grooves are provided on both the upper and lower surfaces; the grooves on the upper surface of the rubber belt are fitted with the filter cake width limiting and pressing block, and the grooves on the lower surface are fitted with the side plate of the vacuum box; and two rows of water-permeable holes are provided in the middle of the long direction of the rubber belt; the filter cake width limiting and pressing block is hydraulically driven, and the lower part is a polyurethane narrow strip that fits into the grooves on the upper surface of the rubber belt.

[0011] As a further technical solution, the vacuum box is rectangular with an open top, and narrow strips of polyurethane are installed on the top of the four upright plates, with the side plates slightly higher than the front and rear plates; the narrow strips of polyurethane on the upper part of the vacuum box are fitted into the grooves on the lower surface of the rubber belt; the vacuum box is movable, and its stroke is detected by a stroke sensor and controlled by an electrical control cabinet.

[0012] As a further technical solution, the filter belt is arranged in a ring-shaped loop, with a polyurethane scraper-type unloading device at the front end, a filter belt washing box at the bottom, an automatic tensioning device and a deviation switch at the tail end, and an automatic deviation correction device in the middle, which can work continuously and stably.

[0013] As a further technical solution, the filter cake shaping roller is driven by an independent motor, has a smooth surface, and is made of stainless steel.

[0014] As a further technical solution, the moisture meter uses microwaves with a wavelength of about 12.24 cm to dry the coal sample and uses a filter cake weighing pan, or uses a wavelength of 1.35~1.5 cm to detect moisture based on the transmission principle. The ash analyzer can be a near-infrared ash analyzer and / or an X-ray ash analyzer; The moisture meter and ash meter are equipped with a walking device for the moisture meter and ash meter, which is driven by a hydraulic motor and transmitted by a chain to control the movement of the ash meter and / or the moisture meter, and the walking device for the moisture meter and ash meter is a horizontal reciprocating type.

[0015] As a further technical solution, the pulping and mixing tank is cylindrical and has a small paddle-type push-down agitator inside. The upper opening of the pulping and mixing tank receives the filter cake discharged by the unloading device of the coal slurry dewatering machine, as well as the filter belt washing water and filtrate that flow out by gravity, for the purpose of re-pulping the filter cake to facilitate its return to the flotation production system.

[0016] The beneficial effects of this invention are as follows: In this invention, dewatering and shaping the coal slurry provides favorable conditions for subsequent water and ash detection. Simultaneously, water measurement before ash content detection also provides favorable conditions for ash content measurement, ensuring the accuracy of ash content detection. In intermittent operation mode, the limit detection error for ash content in flotation concentrate coal slurry is within ±0.5%, and the ash content detection result can be obtained in only about 15 minutes. In continuous operation mode, the limit detection error for ash content in flotation feed coal slurry is within ±1.5%, demonstrating good detection performance in both modes. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are merely some exemplary embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the exemplary embodiments of the present invention and these drawings without any creative effort.

[0018] Figure 1 This is a schematic diagram of a structure according to an embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the structure of the rubber belt in the embodiment; Figure 3 for Figure 2 A schematic diagram of the AA cross-sectional structure of an embodiment; Figure 4 This is a schematic diagram of the structure of the dust cover in one embodiment of the present invention; Figure 5 This is a schematic diagram of the power-on process of the structure shown in this invention; Figure 6 This is a schematic diagram of the shutdown process of the structure shown in this invention; Figure 7 This is a schematic diagram of the discontinuous workflow of the structure shown in this invention. It should be noted that in this diagram, the lines on both sides represent the simultaneous execution of the process, rather than the direction of material flow. Figure 8 This is a schematic diagram of the continuous working process of the structure shown in this invention.

[0019] In the diagram: 1. Sampling control squeeze valve; 2. Defoamer; 3. Coal slurry buffer tank; 4. Coal slurry agitator; 5. Quantitative feed pump; 6. Coal slurry dewatering machine; 7. Redirecting roller; 8. Automatic tensioning device; 9. Filter belt; 10. Rubber belt; 11. Vacuum box; 12. Gas-liquid separator; 13. Circulating water tank; 14. Water ring vacuum pump; 15. Filter belt washing tank; 16. High-pressure nozzle; 17. Redirecting roller assembly; 18. Filter cake re-slurry tank; 19. Filter cake unloading... 20. Material feeding device; 21. Drive roller; 22. Ash analyzer; 23. Dust cover; 24. Water-ash analyzer walking device; 25. Moisture analyzer; 26. Filter cake weighing pan; 27. Automatic correction device; 28. Filter cake shaping roller; 29. ​​Filter cake width limiting and pressing block; 30. Deviation switch; 31. Material feeding funnel; 32. Vacuum box stroke sensor; 33. System built-in electrical control; 34. Centralized control or flotation intelligent control system; 35. Dust removal fan; 36. Sampling switching solenoid valve. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it.

[0021] To keep the drawings concise, each drawing only schematically shows the parts relevant to the invention; these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of components with the same structure or function is schematically shown, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one," and "several" includes "two" and "more than two."

[0022] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0024] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0025] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] like Figures 1-4As shown, this invention illustrates a rapid coal slurry ash content detection system according to an embodiment of the present invention. The system comprises a coal slurry sampling, buffering, quantitative feeding and distribution mechanism, a coal slurry dewatering and dewatering product slurry discharge mechanism, a water and ash detection mechanism, and an electrical control mechanism. Specifically, the coal slurry sampling, buffering, quantitative feeding and distribution mechanism consists of a sampling control squeeze valve 1, a defoamer 2, a coal slurry buffer tank 3, a coal slurry agitator 4, a quantitative feeding pump 5, and a sampling switching solenoid valve 35. The coal slurry dewatering and dewatering product slurry discharge system consists of a coal slurry dewatering machine 6, a filter cake re-slurry tank 18, and a coal slurry agitator 4. The water and ash detection mechanism consists of an ash analyzer 21, a dust cover 22, a water and ash analyzer tracking device 23, and a moisture analyzer 24.

[0027] The rapid coal slurry ash content detection system is placed below the flotation machine; the number of sampling control squeeze valve 1 and sampling switching solenoid valve 35 is consistent with the number of sampling channels, with a diameter of DN20, and is set at the bottom of the pipeline or chute slope section to be sampled.

[0028] The rapid coal slurry ash content detection system can simultaneously sample flotation feed and concentrate coal slurry from the same or different equipment. The sampling point is preferably located at the bottom of the gentle slope section of components such as the flotation feed pipe and the flotation concentrate pipe. The sampled coal slurry is conveyed by gravity, and the sampling pipe diameter is preferably DN20. The sampling volume is controlled by the sampling control squeeze valve 1, and the sampling pipeline is switched by a solenoid valve. The sampling control squeeze valve 1 can be electric or manual, and basically no further adjustments are needed after the system is debugged.

[0029] After sampling, the coal slurry flows into the coal slurry buffer tank 3, which is equipped with a coal slurry agitator 4 and a defoamer 2. The defoamer 2 is located above the coal slurry buffer tank 3 and is used to eliminate air bubbles in the sampled coal slurry in order to detect the ash content of the overall coal slurry as much as possible. The defoamer 2 can adopt existing technology, which will not be described in detail here, such as using the ready-made Tianxingjian C-type defoamer.

[0030] Depending on the concentration difference of the sampled materials, the buffering time of a single-channel mixing tank is generally 1 to 3 minutes, with a larger value used when the concentration is low, in order to provide conditions for quantitative feeding and avoid the subsequent dewatering system from being discontinuous or experiencing variable operating conditions due to unreasonable sampling point settings; the preferred shape of the buffer tank is a cylindrical-conical shape, with a cylindrical upper part and a conical lower part; the overall height-to-diameter ratio is approximately 2.5:1, and the lower cone angle is 45°.

[0031] The coal slurry agitator 4 inside the coal slurry buffer tank 3 is a paddle-type impeller with a blade-down pressure. The impeller tip speed is about 3m / s, the ratio of the impeller diameter to the diameter of the buffer tank 3 is 1:3, the height of the impeller from the bottom is the same as the impeller diameter, and the ratio of the impeller height to the diameter is 1:5. The agitator 4 is set vertically and the center is placed at the interface between the cylinder and the cone of the buffer tank 3.

[0032] The quantitative feed pump 5 is a single screw pump, such as the G20-1 model, with a corresponding flow rate of 0.8 m³ / h. The quantitative feed pump 5 delivers the sampled coal slurry to the distribution funnel 30. The distribution funnel 30 is wider at the top and narrower at the bottom, reciprocating along the length of the coal slurry dewatering machine. Simultaneously, the outlet pipe of the quantitative feed pump 5 reciprocates along the width of the distribution funnel 30, thereby achieving uniform distribution of the coal slurry on the coal slurry dewatering machine and ensuring the uniformity of the material layer thickness and particle size. Furthermore, the coal slurry buffer combined with quantitative feeding better controls the thickness of the filter cake after subsequent coal slurry dewatering, avoiding fluctuations in subsequent dewatering effects and filter cake thickness caused by sampling, thus stabilizing the ash measurement results.

[0033] The coal slurry dewatering machine 6 consists of a redirecting roller 7, an automatic tensioning device 8, a filter belt 9, a rubber belt 10, a vacuum box 11, an air-water separator 12, a circulating water tank 13, a water ring vacuum pump 14, a filter belt washing box 15, a high-pressure nozzle 16, a redirecting roller group 17, a filter cake unloading device 19, a drive roller 20, a dust cover 22, a filter cake weighing pan 25, an automatic correction device 26, a filter cake shaping roller 27, a filter cake width limiting and pressing block 28, a deviation switch 29, a material feeding funnel 30, a vacuum box stroke sensor 31, an electrical control cabinet 32, and a dust removal fan 34.

[0034] The water and ash detection device consists of an ash analyzer 21, a water and ash analyzer travel device 23, and a moisture analyzer 24.

[0035] The redirecting roller 7 is located at the tail of the coal slurry dewatering machine 6 and is tensioned by the automatic tensioning device 8. The drive roller 20 is located at the head of the coal slurry dewatering machine 6. The redirecting roller 7 has a smooth surface, while the drive roller 20 has a rubber-coated surface. It is driven by a frequency converter and its linear speed can be steplessly adjusted within 1~3 m / min. The roller diameter is 150 mm and its length is 350 mm. The automatic tensioning device 8 uses hydraulic pressure to maintain a constant preload.

[0036] The filter belt 9 is made of polypropylene monofilament filter cloth with a pore size of 200 mesh and a width of 300mm. It is arranged in a ring shape. The front end is equipped with a polyurethane scraper unloading device 19, the bottom is equipped with a filter belt washing box 15, the tail end is equipped with a deviation switch 29, and the middle is equipped with an automatic deviation correction device 26.

[0037] The rubber belt 10 has a flat cross-section, is 300mm wide, and has two grooves on both the upper and lower surfaces. The grooves are 2mm wide and 2mm deep, and spaced 200mm apart. There are two rows of water-permeable holes in the middle of the length direction. The upper surface of the rubber belt 10 is used to support the filter belt 9, and the lower surface cooperates with the vacuum box 11 to form a vacuum chamber. The filtrate enters the vacuum box 11 through the water-permeable holes on the rubber belt 10. The rubber belt 10 has a nylon fabric inner core, an overall thickness of 10mm, and is made of nitrile rubber.

[0038] The vacuum box 11 is located below the rubber belt 10 and is rectangular in shape. It is connected to the water ring vacuum pump 14 via the air-water separator 12. The inlet and outlet water pipes of the vacuum pump 14 are connected to the circulating water tank 13. The vacuum box 11 is mobile and automatically returns after traveling a certain distance, continuously repeating the dehydration process. The vacuum box 11 has a length of 0.4m and a stroke of 0.8m. The main body is made of stainless steel and has an open top. The upper part of the four uprights is equipped with narrow polyurethane strips to reduce the friction coefficient with the rubber belt and extend the service life of the rubber belt. At the same time, the narrow polyurethane strips on the upper part of the side plate of the vacuum box 11 fit into the grooves on the lower surface of the rubber belt 10. The vacuum box stroke sensor 31 is an ultrasonic distance sensor that detects the distance and transmits it to the electrical control cabinet 32, and controls the stroke of the vacuum box 11 according to the set distance.

[0039] The water ring vacuum pump 14 has a pumping speed of 15~18 m cubic meters per hour and a vacuum level of MPa. The circulating water tank 13 is used to provide working water for it. The upper part of the gas-liquid separator 12 is conical, and its upper outlet is connected to the pumping port of the water ring vacuum pump 14. The middle part is cylindrical, with a tangential filtrate inlet on it, which is connected to the opening of the bottom plate of the vacuum box. The lower part is also conical, with a filtrate outlet. The overall volume is about 10L. The gas-liquid mixture from the vacuum box 11 enters the gas-liquid separator 12 tangentially, and then gas-liquid separation is achieved under the action of centrifugal force. The filtrate is discharged from the lower outlet, and the gas is discharged by the vacuum pump 14.

[0040] The filter belt 9 corresponds to the movement area of ​​the vacuum box 11 as the filtration section, and the rest is the non-filtration section. After the cake is unloaded, the filter belt is a non-working section. The filter belt in the filtration section is equipped with a filter cake width limiting and pressing block 28 and two high-speed rotating filter cake shaping rollers 27 above it. The filter cake width limiting and pressing block 28 is hydraulically driven. The lower part is a narrow polyurethane strip that fits into the groove on the upper surface of the rubber belt 10 through the filter belt 9. It is used to limit the width of the filter cake and cooperate with the vacuum box 11 to form a tight filtration chamber. The filter cake shaping roller 27 is driven by a separate motor. It has a smooth surface, a diameter of 6cm, and is made of stainless steel. It is used to control the flatness and thickness of the filter cake surface. The final filter cake is flat without obvious bumps that are visible to the naked eye, and the thickness of the filter cake is controlled within 1cm ± 0.3mm.

[0041] The automatic deviation correction device 26 works in conjunction with the deviation switch 29 to automatically correct the deviation of the filter belt 9 and the rubber belt 10. The former is located in the middle of the coal slurry dewatering machine 6 for deviation adjustment; the latter is located at the head and tail of the coal slurry dewatering machine 6 for deviation detection.

[0042] After the coal slurry dewatering machine 6 completes the coal slurry dewatering, it enters the non-filtration section of the filter belt 9; and the non-filtration section is equipped with a moisture meter 24 and an ash meter 21, as well as a walking device 23 for water and ash detection; the walking device 23 for water and ash detection is driven by a hydraulic motor and also uses chain drive, and the walking mode is horizontal reciprocating.

[0043] The filter belt 9 is separated from the rubber belt 10 by the redirecting roller group 17 in front of the moisture meter 24. Then the filter cake and filter belt are supported by the filter cake weighing pan 25. After the filter cake reaches constant weight or the moisture content is measured, it is moved to the bottom of the ash analyzer 21. The preferred weighing pan 25 is composed of a 3mm thick ceramic plate and a weighing sensor. The sensor is piezoelectric ceramic type, with a range of 0~1kg and an accuracy of 0.01g. It is arranged at the four corners of the filter cake weighing pan 25. The sensor is piezoelectric ceramic type, and its signal is amplified by the circuit and then transmitted to the electronic control device.

[0044] The redirecting roller group 17, as shown in the figure, consists of 8 rollers. It has a smooth surface and its diameter is half that of the redirecting roller 7. It is used to redirect the operation of the rubber belt 10 and the filter belt.

[0045] In intermittent operation mode, the moisture meter 24 uses a wavelength of 12.24 cm to dry the coal sample. After the weighing sensor reaches a constant weight within 3 minutes, the sample is transferred to the ash analyzer. In continuous operation mode, it uses a wavelength of 1.35~1.5 cm to detect moisture based on the transmission principle. The moisture meter 24 measures moisture to eliminate the influence of moisture on the ash content detection results. Furthermore, fluctuations in the moisture measurement value reflect the system's operating status and the degree of change in coal quality, alerting the operator to check when moisture levels change significantly.

[0046] The ash analyzer 21 uses a wavelength of 1100~2500 nm and is based on the principle of long-wave transmission for detection. This can more effectively avoid inaccurate ash content detection caused by material segregation during coal slurry filtration and dewatering. Alternatively, multi-energy X-rays can be used to detect filter cake ash content based on the attenuation of reflected light. The ash analyzer 21 uses existing ash content detection instruments, which will not be described in detail here.

[0047] In the embodiments described, the moisture meter 24, the ash meter 21, and the coal slurry sampling, buffering, quantitative feeding, and coal slurry dewatering functions are all single-channel configurations.

[0048] The ash analyzer 21, together with part of the dewatering device of the coal slurry dewatering machine 6 below, is semi-sealed inside the stainless steel box 22. The stainless steel box 22 is equipped with a baffle, and a pipe in the middle is connected to the external dust removal fan 34, so that the stainless steel box is always under negative pressure, avoiding dirt from the lens of the near-infrared or X-ray ash analyzer.

[0049] The filter cake unloading device 19 is made of polyurethane wear-resistant material and is pressed onto the filter belt 9 by a detachable spring. It is used to remove the filter cake after coal slurry dewatering.

[0050] The filter belt washing tank 15 is equipped with three rows of high-pressure nozzles 16 along the full width of the filter belt. The washing liquid flow rate can be adjusted within 80~85mL / min. At the same time, the electrical control cabinet 32 ​​is equipped with a filter belt 9 rinsing water flow and water pressure detection device.

[0051] The filter belt washing tank 15 is equipped with three rows of high-pressure nozzles 16 along the full width of the filter belt, which are used to continuously clean the working and non-working surfaces of the filter belt 9, thereby regenerating the filter belt and preventing the filter belt from becoming clogged due to continuous operation, which would lead to a decrease in dewatering effect. Meanwhile, the electrical control cabinet 32 ​​is equipped with a device to detect the flow rate and pressure of the filter belt 9's washing water to ensure the permeability of the filter belt 9. Preferably, the high-pressure nozzles 16 are those used in coal preparation plants for desliming, and preferably, one nozzle is installed on the non-working surface and two on the working surface of a single-path filter belt 9. Preferably, the nozzle outlet is DN15.

[0052] The filter cake re-pulping tank 18 is cylindrical and has a small paddle-type push-down agitator 4 inside. Its upper opening receives the filter cake discharged by the unloading device, as well as the filter belt washing water and filtrate that flow out by gravity, for re-pulping the filter cake to facilitate its return to the flotation production system.

[0053] Electrical control cabinet 32 ​​is used to detect the tension, misalignment, filter belt flushing water volume, vacuum pump circulating water volume, etc. of the system, so as to fully ensure the stability of the system operation.

[0054] The entire system is integrated into a tooling housing, making the system appearance more concise. The front of the housing has a local display of the system's operating status and test results. At the same time, the operating status and test results can also be transmitted remotely to an industrial centralized control system or a flotation intelligent control system via fiber optic or network cable.

[0055] In this embodiment, the coal slurry is sampled by gravity flow. The sampling amount is controlled by the squeeze valve 1. After being collected into the coal slurry buffer mixing tank 4, it is quantitatively fed to the coal slurry dewatering machine 6 by the single screw pump 5. Then, the filter cake is first flattened and smoothed, then tested for water and ash content, and finally discharged by the unloading device 19 and returned to the flotation feed after slurry making.

[0056] This invention has two working modes. When the moisture meter 21 adopts the principle of evaporation, it is an intermittent ash content detection mode. In this mode, only one moisture meter 21 and one ash meter 24 are needed, and only one circuit needs to be set for coal slurry sampling, buffering, quantitative feeding, coal slurry dewatering, and water-ash meter. During operation, the coal slurry to be sampled is fed into the coal slurry buffer tank 3 by gravity. After reaching a certain liquid level, sampling is stopped. Then, the slurry is fed to the coal slurry dewatering machine 6 through the quantitative feeding pump 5 and the material distribution funnel 30 for dewatering. After the coal slurry is dewatered, the filter cake enters the moisture meter 21 for evaporation. While the filter cake is being microwave-evaporated, other coal slurry samples can be sampled and buffered. After the filter cake is dried, it enters the ash meter 24 to detect the ash content of the material. At the same time, quantitative feeding is used to feed and dewater other coal slurries. This mode is more suitable for occasions with strict requirements for coal slurry ash content detection, such as flotation clean coal.

[0057] This invention has two working modes. When the moisture meter 21 uses the transmission principle to detect moisture, it is a continuous ash detection mode. In this mode, sampling, buffering, quantitative feeding, material distribution, coal slurry dewatering, and water and ash detection are all carried out continuously. However, each path must be equipped with a sampling, buffering, quantitative feeding, material distribution, and coal slurry dewatering machine. One moisture meter 21 and one ash meter 24 are still required. The walking device 23 is used to perform water and ash detection on different paths. This mode is suitable for situations with a large number of equipment and complex processes, but where the requirements for coal slurry ash detection results are not very strict, such as flotation feed.

[0058] like Figure 5 As shown, the boot process of this invention is as follows: S1: Start the filter belt flushing water and water / ash detector; S2: Equipment self-test; S3: Perform the following operating parameter checks: S3.1 / Ash content test value S3.2 / Moisture content test value S3.3. If there are no problems with tension test, flushing water flow test, belt misalignment test, and vacuum pump circulating water flow test, and the ash content and moisture content test values ​​are within the error range of the filter belt's own calibration value, proceed to S5. S4: If S3 fails, manual verification is required; S5: If S3 passes, the drive drum will be activated, and the filter belt will operate normally. S6: Open the coal slurry mixing buffer tank and start the defoamer at the same time; S7: Turn on the sampling squeeze valve, vacuum pump, and shaping roller; S8: When the buffer tank level reaches the specified height, start the metering feed pump; S9: Normal dehydration, moisture and ash content measurement, unloading, filter belt rinsing and pulping discharge.

[0059] like Figure 6 As shown, the shutdown process of this invention is as follows: M1: Close the sampling valve and the quantitative feed pump, and empty the buffer tank by gravity. M2: Stop the shaping roller and water-cement meter; M3: Turn off the vacuum pump after the filter cake has been completely discharged; M4: After cleaning the filter belt, turn off the flushing water to complete the shutdown.

[0060] like Figure 7 As shown, the discontinuous workflow of the present invention is as follows: D1: Sampling; D2: Sampling stops once the buffer tank reaches a certain liquid level; D3: Start the quantitative feed pump to distribute the material and dewater the coal slurry dewatering machine; after the liquid level in the buffer tank reaches a certain level, open the vent valve to flush the buffer tank, feed pump and distributor. D4: Microwave-dried filter cake; D5: Ash content detection of filter cake; It should be noted that in this diagram, the lines on both sides represent the simultaneous execution of processes, not the direction of material flow.

[0061] like Figure 8 As shown, the continuous workflow of the present invention is as follows: L1: Continuous sampling; L2: After the buffer tank reaches a certain liquid level, the metering feed pump is turned on to feed continuously; L3: Coal slurry dewatering machine - feeding and dewatering; L4: Microwave continuous detection of moisture content in dehydrated materials; L5: Continuous ash content detection of dehydrated materials.

[0062] After measuring water and ash content, the system can store the test results from different times, along with the sampling time and operating conditions, into a database to provide data for intelligent control or manual adjustment of the subsequent flotation process.

[0063] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A rapid detection system for coal slurry ash content, characterized in that, include: The gravity-flow sampling tube, which can be one or more tubes, is used for coal slurry sampling; A buffer mixing tank is used to buffer samples taken by the gravity sampling tube. A fabric funnel, the fabric funnel being used for fabric; A metering pump is used to feed the material in the buffer mixing tank into the cloth funnel in a specific direction; Coal slurry dewatering machine, the coal slurry dewatering machine is used for dewatering coal slurry after it is fed by the feeding mechanism; A pulping and mixing tank, wherein the pulping and mixing tank is used for pulping and discharging dewatered products; A microwave moisture meter, an ash meter, and a water-ash meter traveling device and a dust removal device for controlling the moisture meter and the ash meter.

2. The rapid coal slurry ash content detection system according to claim 1, characterized in that, The gravity sampling pipe samples coal slurry, and the sampling amount is controlled by the squeeze valve. The sampling pipeline is switched by the solenoid valve. The number of sampling pipelines is consistent with the number of sampling channels. It is set at the bottom of the pipeline to be sampled or the gentle slope section of the chute. The coal slurry buffer tank is equipped with a coal slurry agitator and a defoamer inside, which are used to buffer the sampled coal slurry. The buffering time for a single channel is about 1 to 3 minutes.

3. The rapid coal slurry ash content detection system according to claim 1, characterized in that: The quantitative feeding is carried out using a single screw pump and fed to the coal slurry dewatering machine through a distribution funnel; The feeding hopper can reciprocate along the length of the coal slurry dewatering machine, while the outlet pipeline of the quantitative feed pump reciprocates along the width of the feeder.

4. The rapid coal slurry ash content detection system according to claim 1, characterized in that... The coal slurry dewatering machine includes: a rubber belt, a filter belt, a vacuum box, a gas-water separator, a vacuum pump, a filter cake width limiting and pressing block, a filter cake shaping roller, a vacuum box stroke sensor, a filter cake weighing device, a filter belt washing box, and a dust removal fan.

5. The rapid coal slurry ash content detection system according to claim 4, characterized in that: The cross-section of the rubber belt is a flat belt, and grooves are provided on both the upper and lower surfaces. The grooves on the upper surface of the rubber belt are fitted with the filter cake width limiting and pressing block, and the grooves on the lower surface are fitted with the side plate of the vacuum box. Two rows of water-permeable holes are provided in the middle of the long direction of the rubber belt. The filter cake width limiting and pressing block is hydraulically driven, and the lower part is a narrow polyurethane strip that fits into the grooves on the upper surface of the rubber belt.

6. The rapid coal slurry ash content detection system according to claim 4, characterized in that: As a further technical solution, the vacuum box is rectangular with an open top, and narrow strips of polyurethane are installed on the top of the four upright plates, with the side plates slightly higher than the front and rear plates; the narrow strips of polyurethane on the upper part of the vacuum box are fitted into the grooves on the lower surface of the rubber belt; the vacuum box is movable, and its stroke is detected by a stroke sensor and controlled by an electrical control cabinet.

7. The rapid coal slurry ash content detection system according to claim 4, characterized in that: The filter belt is arranged in a ring-shaped loop, with a polyurethane scraper-type unloading device at the front end, a filter belt washing box at the bottom, an automatic tensioning device and a deviation switch at the tail end, and an automatic deviation correction device in the middle, which can work continuously and stably.

8. The rapid coal slurry ash content detection system according to claim 4, characterized in that: The filter cake shaping roller is driven by an independent motor, has a smooth surface, and is made of stainless steel.

9. A rapid coal slurry ash content detection system according to claim 1, characterized in that: The moisture meter uses microwaves with a wavelength of about 12.24 cm to dry the coal sample and works in conjunction with a filter cake weighing pan, or uses a wavelength of 1.35~1.5 cm to detect moisture based on the principle of transmission. The ash analyzer can be a near-infrared ash analyzer and / or an X-ray ash analyzer; The moisture meter and ash meter are equipped with a walking device for the moisture meter and ash meter, which is driven by a hydraulic motor and transmitted by a chain to control the movement of the ash meter and / or the moisture meter, and the walking device for the moisture meter and ash meter is a horizontal reciprocating type.

10. A rapid coal slurry ash content detection system according to claim 7, characterized in that: As a further technical solution, the pulping and mixing tank is cylindrical and has a small paddle-type push-down agitator inside. The upper opening of the pulping and mixing tank receives the filter cake discharged by the unloading device of the coal slurry dewatering machine, as well as the filter belt washing water and filtrate that flow out by gravity, for the purpose of re-pulping the filter cake to facilitate its return to the flotation production system.

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