A pulverized coal collection and granulation device during the upgrading process of low-rank coal

Abstract

The present invention relates to a pulverized coal collection and granulation device during the upgrading process of low-rank coal, effectively solving the technical problems that during the upgrading of existing low-rank coal, wet dust removal requires re-drying, and dust collectors are prone to clogging, leakage, large resistance and low efficiency. It includes a tower body, a flue gas inlet, a flue gas outlet, a cleaning system, a liquid preparation system, a centrifugal atomizer, a conical centrifugal sieve, a swirl plate, a conical finished product bin, and a discharger. The present invention provides a pulverized coal collection and granulation device in the drying process of lignite and coal slime with a simple overall structure, small operating resistance, no filter bags, no clogging, high pulverized coal collection efficiency, safety and stability. The present invention solves many problems such as traditional pulverized coal collection pollution, difficult granulation, spontaneous combustion and explosion, and inconvenient long-distance transportation and storage. It has the characteristics of a simple overall structure, high pulverized coal collection rate, large coal particles, no filter bags, no clogging and spontaneous combustion, high purification rate, and safe operation.

Description

Technical Field

[0001] The present invention relates to the technical field of coal processing, and specifically to a device for collecting and granulating pulverized coal during the upgrading of low-rank coal, mainly including a device for collecting and granulating pulverized coal during the upgrading of low-rank coal and a preparation and use method of a curing material for pulverized coal granulation. Background Art

[0002] With the clean and efficient utilization of coal in China, higher requirements have been put forward for coal processing and utilization. Due to the characteristics of lignite and slime, such as high water content, small particle size, high volatile matter, easy weathering and spontaneous combustion, and low calorific value, it is difficult to transport, store and realize industrial applications. Dehydration and upgrading treatment to reduce the moisture content of lignite and slime, improve the fuel calorific value, and reduce the transportation cost is an important way to expand the clean and efficient utilization of low-rank coal such as lignite and slime. For this reason, pulverized coal drying and upgrading has become the key content of coal preparation plants, lignite upgrading and coal powder preparation enterprises.

[0003] At present, most coal washing plants and lignite upgrading enterprises use methods such as sprinkling dust suppression, cyclone dust collectors, bag dust collectors or wet dust collectors to collect dried pulverized coal, soot and dust in the lignite and slime drying processes. Although sprinkling dust suppression or wet dust collectors have a certain collection effect, they increase the moisture content of the pulverized coal and the processing capacity of the drying system; while using methods such as rotary kilns and dust collectors to collect pulverized coal, due to the fine particle size, large collection volume of pulverized coal, and easy occurrence of pulverized coal leakage, blockage, and filter bag powder accumulation in the process, it not only causes a large resistance and low efficiency of the dust collector, but also easily leads to the risk of spontaneous combustion and explosion of pulverized coal.

[0004] On this basis, the present invention provides a device for collecting and granulating pulverized coal during the upgrading of low-rank coal to solve the above problems. Summary of the Invention

[0005] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a device for collecting and granulating pulverized coal during the upgrading of low-rank coal. The present invention effectively solves the technical problems that wet dust removal requires re-drying during the upgrading of existing low-rank coal, and the dust collector is prone to blockage, leakage, large resistance and low efficiency.

[0006] A device for collecting and granulating pulverized coal during the upgrading of low-rank coal, characterized by comprising a tower body, a flue gas inlet, a flue gas outlet, a cleaning system, a liquid preparation system, a centrifugal atomizer, a conical centrifugal screen, a swirl plate, a conical finished product bin, and a discharger;

[0007] The flue gas inlet is arranged at the lower end of the outer side of the tower body, and the flue gas outlet is arranged at the top of the tower body;

[0008] At the upper end inside the tower body, there is a centrifugal atomizer placed above the flue gas inlet. At the upper end of the centrifugal atomizer, there is a conical centrifugal sieve. At the upper end of the conical centrifugal sieve, there is a swirl plate. At the upper end of the swirl plate, there is a spray head, and the spray head is connected to a cleaning system placed outside the tower body;

[0009] The centrifugal atomizer is connected to a liquid preparation system placed outside the tower body, and a pulverized coal granulation and solidification material solution with a content of 8% is added to the liquid preparation system;

[0010] At the lower end inside the tower body, there is a conical finished product bin placed below the centrifugal atomizer, and a discharger is arranged at the lower end of the conical finished product bin;

[0011] The preparation method of the pulverized coal granulation and solidification material is as follows:

[0012] Prepare raw materials in parts by mass:

[0013] 45 - 65 parts of tapioca flour, 2 - 5 parts of peracetic acid, 5 - 8 parts of sodium hydroxide, 6 - 12 parts of magnesium chloride, 2 - 5 parts of sodium hydroxyethyl sulfonate, 20 - 25 parts of sodium silicate;

[0014] The preparation method is as follows:

[0015] (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water in a ratio of 1:1 to prepare an aqueous solution for standby;

[0016] (2) Add 45 - 65 parts of tapioca flour to the reaction kettle with stirring, and atomize and spray 2 - 5 parts of peracetic acid solution for oxidation;

[0017] (3) Atomize and spray 5 - 8 parts of sodium hydroxide solution into the oxidized tapioca flour with stirring for activation;

[0018] (4) Atomize and spray 6 - 12 parts of magnesium chloride solution into the activated tapioca flour with stirring for catalysis;

[0019] (5) Heat the above mixture to 90 °C, add 2 - 5 parts of sodium hydroxyethyl sulfonate for esterification with stirring, stir for 160 min to form a hydroxyethyl copolymer. After cooling to room temperature, add 20 - 25 parts of sodium silicate, stir evenly, and pulverize to obtain the product;

[0020] Then;

[0021] (1) Introduce the pulverized coal flue gas into the flue gas inlet of the tower body, and at the same time, start the centrifugal atomizer and the liquid preparation system in sequence;

[0022] (2) Spray and atomize the pulverized coal granulation and solidification material solution prepared by the liquid preparation system into the pulverized coal and flue gas in the tower body through the centrifugal atomizer;

[0023] (3) The pulverized coal granulation and solidification material solution atomized by high-pressure spraying collides, wets, adheres to, and condenses with the pulverized coal flue gas, causing the pulverized coal to agglomerate into pulverized coal particles. As the pulverized coal particles settle while increasing in size and weight, they are then dried by the high-temperature flue gas and settle in the conical finished product bin.

[0024] (4) The small particles agglomerated in the tower body rise with the flue gas and are filtered through a conical centrifugal sieve. The small particles are cyclically agglomerated into large particles that increase in size and weight, and then are dried by the high-temperature flue gas and settle in the conical finished product bin.

[0025] (5) The flue gas filtered by the conical centrifugal sieve enters a cyclone plate for gas-solid separation. The purified flue gas is discharged from the flue gas outlet, and the separated fine particles sink and participate in the cyclic granulation again.

[0026] Preferably, the peracetic acid is anhydrous peracetic acid; the sodium silicate is powdered instant sodium silicate; the magnesium chloride is anhydrous magnesium chloride.

[0027] Preferably, the reaction formula of the preparation method is:

[0028]

[0029] Preferably, 65 parts of cassava starch, 2 parts of peracetic acid, 5 parts of sodium hydroxide, 6 parts of magnesium chloride, 2 parts of sodium hydroxyethyl sulfonate, and 20 parts of sodium silicate.

[0030] Preferably, 58 parts of cassava starch, 3 parts of peracetic acid, 6 parts of sodium hydroxide, 8 parts of magnesium chloride, 3 parts of sodium hydroxyethyl sulfonate, and 22 parts of sodium silicate.

[0031] Preferably, 50 parts of cassava starch, 4 parts of peracetic acid, 7 parts of sodium hydroxide, 11 parts of magnesium chloride, 4 parts of sodium hydroxyethyl sulfonate, and 24 parts of sodium silicate.

[0032] Preferably, 45 parts of cassava starch, 5 parts of peracetic acid, 8 parts of sodium hydroxide, 12 parts of magnesium chloride, 5 parts of sodium hydroxyethyl sulfonate, and 25 parts of sodium silicate.

[0033] Preferably, the flue gas inlet is placed on the tower body at an inclination of 45° upward.

[0034] Preferably, the liquid preparation system includes a liquid preparation shell, in which a stirrer and a submersible slurry pump are installed. The inside of the liquid preparation shell is connected to a centrifugal atomizer through a liquid delivery pipeline.

[0035] Preferably, the cleaning system includes a cleaner placed outside the tower body. A water pump is installed inside the cleaner, and the water pump is connected to a spray head placed above the conical centrifugal sieve through a water pipe.

[0036] The present invention has the following technical effects.

[0037] 1. Through the design of the functional structure, the device of the present invention eliminates the "lignite, coal slime → drying → pulverized coal collection → granulation → industrial fuel" technical process of traditional processes such as granulation by coal powder briquetting machines, particle drying furnaces, and soot treatment equipment, and solves the problems of large site occupation, complex equipment processes, large investment, high drying energy consumption, and low resource utilization rate in traditional high-pressure ball making of dried pulverized coal from lignite and coal slime. By organically combining and assembling the tower body, flue gas inlet, flue gas outlet, cleaning system, liquid preparation system, centrifugal atomizer, conical centrifugal screen, cyclone plate, conical finished product bin, and discharger, through the adsorption, condensation and solidification of the coal powder granulation solidification material solution, a coal powder collection and granulation device in the lignite and coal slime drying process with high coal powder collection rate, fast granulation, non-blocking, no filter bag, low operating cost, high purification effect, safety and stability is formed. It has the characteristics of small floor area, compact structure, simple process, small resistance, large processing capacity, high efficiency, and prevention of flammable and explosive coal powder.

[0038] 2. Based on the traditional method of collecting pulverized coal such as dust collectors, due to the fine particle size of pulverized coal, difficult to form, large collection volume, easy to cause situations such as pulverized coal leakage, blockage, filter bag powder accumulation, spontaneous combustion and explosion in the process, using the properties of the coal powder granulation solidification material solution such as wetting penetration, condensation and solidification, fire safety, etc., the coal powder granulation solidification slurry is atomized under high pressure by the centrifugal atomizer into the rising pulverized coal flue gas, and through the processes of reverse encounter, collision and capture, wetting, adsorption, condensation, etc. of the coal powder granulation solidification material, the pulverized coal condenses into agglomerated particles, improving the characteristics of small particle size, large porosity, easy to absorb water, poor thermal stability, and difficult to form of dried pulverized coal, promoting the granulation rate and particle strength of dried pulverized coal, and solving the problems of pulverized coal collection, coal dust pollution, difficult to granulate, spontaneous combustion and explosion, inconvenient transportation and storage of pulverized coal, and difficult industrial application in the pulverized coal drying and collection process of coal processing enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings are used to provide a further understanding of the invention and constitute a part of the specification, and are used to explain the invention together with the embodiments of the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0040] Figure 1 It is a schematic diagram of the overall internal structure installation of the present invention.

[0041] Reference Signs:

[0042] 1: Tower body; 2: Flue gas inlet; 3: Flue gas outlet; 4: Cleaning system; 5: Liquid preparation system; 6: Centrifugal atomizer; 7: Conical centrifugal screen; 8: Cyclone plate; 9: Conical finished product bin; 10: Discharger. DETAILED DESCRIPTION OF THE INVENTION

[0043] Regarding the foregoing and other technical contents, features and effects of the present invention, in the following with reference to the attached Figure 1In the detailed description of the embodiments, it will be clearly presented. The content mentioned in the following embodiments is all referenced to the accompanying drawings of the specification.

[0044] The exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.

[0045] A pulverized coal collection and granulation device during the low-rank coal upgrading process includes a tower body 1, a flue gas inlet 2, a flue gas outlet 3, a cleaning system 4, a liquid preparation system 5, a centrifugal atomizer 6, a conical centrifugal sieve 7, a cyclone plate 8, a conical finished product bin 9, and a discharger 10.

[0046] A flue gas inlet 2 is arranged at the lower part outside the tower body 1, and the tower body 1 is made of stainless steel; the flue gas inlet 2 is designed to be inclined upward at 45°, and a flue gas outlet 3 is arranged at the top of the flue gas inlet 2.

[0047] A centrifugal atomizer 6 is arranged at the upper end inside the tower body 1, a conical centrifugal sieve 7 is arranged above the centrifugal atomizer 6, a cyclone plate 8 is arranged above the conical centrifugal sieve 7, and a nozzle of the cleaning system 4 is arranged above the cyclone plate 8. The cleaning system 4 is connected to a controller.

[0048] A liquid preparation system 5 is arranged outside the tower body 1. The liquid preparation system 5 includes a liquid preparation shell, in which a mixer, a submersible slurry pump, and an infusion pipeline are installed. The upper end of the infusion pipeline communicates with the centrifugal atomizer 6. The liquid preparation system 5 is connected to a controller.

[0049] A conical finished product bin 9 is arranged at the lower end inside the tower body 1, a discharger 10 is arranged at the lower end of the conical finished product bin 9, and the discharger 10 is connected to a controller.

[0050] The cleaning system 4 includes a cleaner placed outside the tower body 1. The cleaner is internally provided with a water pump. The water pump is connected to a nozzle placed inside the tower body 1 and above the conical centrifugal sieve 7 through a water pipe. The atomizer is the centrifugal atomizer 6.

[0051] The conical centrifugal sieve 7 is a conical mesh filter sieve.

[0052] The cyclone plate 8 is a gas-solid-liquid separation device composed of cylindrical blades, also called a cyclone, and is also connected to a controller.

[0053] The conical finished product bin 9 is a finished product bin with a conical feed inlet.

[0054] And a pulverized coal granulation solidification material solution with a content of 8% is added to the liquid preparation system 5.

[0055] When operating and using:

[0056] The pulverized coal collection and granulation steps are as follows:

[0057] 1. In the mixer of the liquid preparation system 5, the pulverized coal granulation solidification material is dissolved in water to form a slurry with a content of 6 - 10% for standby, taking 8% as an example;

[0058] 2. Introduce the pulverized coal flue gas into the tower body 1 through the flue gas inlet 2, and at the same time, start the centrifugal atomizer 6 and the liquid delivery pump of the liquid preparation system 5 in sequence.

[0059] 3. In the tower body 1, spray and atomize the pulverized coal granulation and solidification material solution prepared by the liquid preparation system 5 through the centrifugal atomizer 6 into the pulverized coal flue gas in the tower body 1.

[0060] 4. In the tower body 1, through processes such as collision, wetting, adhesion, and condensation between the pulverized coal granulation and solidification material solution by high-pressure spray atomization and the pulverized coal flue gas, the pulverized coal agglomerates into pulverized coal particles. As the pulverized coal particles settle while increasing in size and weight, they are then dried by the high-temperature flue gas and settle into the conical finished product bin.

[0061] 5. In the tower body 1, the agglomerated small particles rise with the flue gas, are filtered by the conical centrifugal screen 7, the small particles are cyclically agglomerated into large particles that increase in size and weight, and then are dried by the high-temperature flue gas and settle into the conical finished product bin 9.

[0062] 6. The flue gas filtered by the conical centrifugal screen 7 enters the cyclone plate 8 for gas-solid separation. The separated fine particles sink and participate in the cyclic granulation again, and the purified flue gas is discharged from the outlet.

[0063] The tower body 1 of the present invention is made of stainless steel, which improves the corrosion resistance, high-temperature resistance, and wear resistance of the tower body 1; a flue gas inlet 2 with an inclination angle of 45 degrees is arranged outside the tower body 1, and a conical finished product bin 9 with a conical hopper is designed at the lower part inside the tower body 1 to prevent the particles in the conical finished product bin 9 from being sucked away by the wind and returning to granulation; a wear-resistant lining plate with an inclination angle of 20° is designed on the inner side of the tower body 1, so that the material rotates and rises from the flue gas inlet, reducing the accumulation of materials on the tower wall and enabling the granulation production to proceed smoothly.

[0064] The cleaning system 4 of the present invention can avoid the blockage of the conical centrifugal screen 7 by pulverized coal particles, effectively improve the filtering effect on fine pulverized coal particles, and ensure the stable operation of the device by cleaning the inner wall of the tower body 1 and the centrifugal atomizer 6, conical centrifugal screen 7, and cyclone plate 8 that work for a long time at irregular intervals.

[0065] The centrifugal atomizer 6 of the present invention is a high-speed rotating pulverized coal granulation and solidification slurry atomization device; the delivery pump of the liquid preparation system 5 is a submersible slurry pump suitable for transporting viscous slurry; through the combination of a series of devices, the problems of low atomization efficiency, poor atomization effect, and instability of the atomization process of the pulverized coal granulation and solidification slurry are solved.

[0066] A detachable tower cap is arranged at the upper part of the tower body 1 of the present invention, which is convenient for the maintenance and replacement of the devices inside the tower body 1.

[0067] The conical centrifugal sieve 7 of the present invention is a filtering device that rotates centrifugally with a conical net-shaped breathable filter material; the cyclone plate 8 is a solid-liquid-gas separation device composed of cylindrical blades made of FRPP material. Through the comprehensive actions of collision, adhesion, aggregation, and centrifugal separation between the pulverized coal granulation solidification material solution droplets atomized at high speed by the centrifugal atomizer 6 and the pulverized coal flue gas, large particles are formed from the pulverized coal dust. The large particles fall into the conical finished product bin after being dried by the high-temperature flue gas during sedimentation; the atomized fine particles pass through the filtration of the conical centrifugal sieve 7 and the solid-liquid-gas separation of the cyclone plate 8 with the rising flue gas, return to the tower body 1, and aggregate into large particles when encountering the pulverized coal flue gas. Through multiple recirculations of the pulverized coal granulation solidification material solution, the contact time between the granulation slurry and the pulverized coal dust is extended to achieve the purpose of high-efficiency desulfurization. After drying, they fall into the conical finished product bin 9, and the purified gas rises from the flue gas outlet 3. The dust removal efficiency can reach more than 98.5%, and it has the characteristics of fast pulverized coal granulation, large gel particles, high yield, process stability, and good dust removal effect.

[0068] Specific preparation method of the 8% pulverized coal granulation solidification material solution:

[0069] Prepare raw materials in parts by mass:

[0070] 45 - 65 parts of tapioca flour, 2 - 5 parts of peracetic acid, 5 - 8 parts of sodium hydroxide, 6 - 12 parts of magnesium chloride, 2 - 5 parts of sodium hydroxyethyl sulfonate, 20 - 25 parts of sodium silicate;

[0071] The preparation method is as follows:

[0072] (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water in a ratio of 1:1 to prepare an aqueous solution for later use;

[0073] (2) Add 45 - 65 parts of tapioca flour to the reaction kettle under stirring, and atomize and spray 2 - 5 parts of peracetic acid solution for oxidation;

[0074] (3) During stirring, atomize and spray 5 - 8 parts of sodium hydroxide solution into the oxidized tapioca flour for activation;

[0075] (4) During stirring, atomize and spray 6 - 12 parts of magnesium chloride solution into the activated tapioca flour for catalysis;

[0076] (5) Heat the above mixture to 90 °C, add 2 - 5 parts of sodium hydroxyethyl sulfonate for esterification during stirring, stir for 160 min to form a hydroxyethyl copolymer. After cooling to room temperature, add 20 - 25 parts of sodium silicate, stir evenly, and pulverize to obtain the product.

[0077] The peracetic acid is anhydrous peracetic acid; the sodium silicate is powdered instant sodium silicate; the magnesium chloride is anhydrous magnesium chloride.

[0078] The reaction formula of the preparation method is:

[0079]

[0080] Example 1.

[0081] The pulverized coal granulation solidifying material is dissolved in water to form a pulverized coal granulation solidifying material solution with a content of 8%. The pulverized coal granulation solidifying material solution is sprayed into a pulverized coal collector or a dust removal tower by a high-pressure spraying device, so that it is in close contact with the pulverized coal in the hot air. Under the action of centrifugal force, by changing the characteristics of the pulverized coal, granulation functions such as wetting, bonding, and agglomeration of the pulverized coal and physical and chemical effects are carried out, so that the pulverized coal agglomerates into particles. With the action of the countercurrent hot air, the pulverized coal particles settle in the finished product bin during the process of increasing and drying.

[0082] The raw material ratio of the pulverized coal granulation solidifying material solution with a content of 8% is as follows:

[0083] Prepare the raw materials in parts by mass:

[0084] 65 parts of tapioca flour, 2 parts of peracetic acid, 5 parts of sodium hydroxide, 6 parts of magnesium chloride, 2 parts of sodium hydroxyethyl sulfonate, 20 parts of sodium silicate;

[0085] The preparation method is as follows:

[0086] (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water at a ratio of 1:1 to form an aqueous solution for standby;

[0087] (2) Add 65 parts of tapioca flour to the reaction kettle and stir, and atomize and spray 2 parts of peracetic acid solution for oxidation;

[0088] (3) During stirring, atomize and spray 5 parts of sodium hydroxide solution into the oxidized tapioca flour for activation;

[0089] (4) During stirring, atomize and spray 6 parts of magnesium chloride solution into the activated tapioca flour for catalysis;

[0090] (5) Heat the above mixture to 90 °C, add 2 parts of sodium hydroxyethyl sulfonate during stirring for esterification, stir for 160 min to form a hydroxyethyl copolymer, cool to room temperature, and then add 20 parts of sodium silicate, stir evenly and pulverize to obtain the product.

[0091] Example 2.

[0092] The pulverized coal granulation solidifying material is dissolved in water to form a pulverized coal granulation solidifying material solution with a content of 8%. The pulverized coal granulation solidifying material solution is sprayed into a pulverized coal collector or a dust removal tower by a high-pressure spraying device, so that it is in close contact with the pulverized coal in the hot air. Under the action of centrifugal force, by changing the characteristics of the pulverized coal, granulation functions such as wetting, bonding, and agglomeration of the pulverized coal and physical and chemical effects are carried out, so that the pulverized coal agglomerates into particles. With the action of the countercurrent hot air, the pulverized coal particles settle in the finished product bin during the process of increasing and drying.

[0093] The raw material ratio of the pulverized coal granulation solidification material solution with a content of 8% is as follows:

[0094] Prepare the raw materials in parts by mass:

[0095] 58 parts of tapioca flour, 3 parts of peracetic acid, 6 parts of sodium hydroxide, 8 parts of magnesium chloride, 3 parts of sodium hydroxyethyl sulfonate, and 22 parts of sodium silicate;

[0096] The preparation method is as follows:

[0097] (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water in a ratio of 1:1 to prepare an aqueous solution for standby;

[0098] (2) Add 58 parts of tapioca flour to the reaction kettle under stirring, and atomize and spray 3 parts of peracetic acid solution for oxidation;

[0099] (3) During stirring, atomize and spray 6 parts of sodium hydroxide solution into the oxidized tapioca flour for activation;

[0100] (4) During stirring, atomize and spray 8 parts of magnesium chloride solution into the activated tapioca flour for catalysis;

[0101] (5) Heat the above mixture to 90 °C, add 3 parts of sodium hydroxyethyl sulfonate for esterification during stirring, stir for 160 min to form a hydroxyethyl copolymer. After cooling to room temperature, add 22 parts of sodium silicate, stir evenly, and pulverize to obtain the product.

[0102] Example 3.

[0103] Dissolve the pulverized coal granulation solidification material in water to form a pulverized coal granulation solidification material solution with a content of 8%. Use a high-pressure spraying device to spray the pulverized coal granulation solidification material solution into the pulverized coal collector or dust removal tower, so that it is in close contact with the pulverized coal in the hot air. Under the action of centrifugal force, by changing the characteristics of the pulverized coal, the granulation functions such as wetting, bonding, and agglomeration of the pulverized coal and physical and chemical effects are carried out, so that the pulverized coal agglomerates into particles. With the action of the countercurrent hot air, the pulverized coal particles settle in the finished product bin during the process of increasing and drying.

[0104] The raw material ratio of the pulverized coal granulation solidification material solution with a content of 8% is as follows:

[0105] Prepare the raw materials in parts by mass:

[0106] 50 parts of tapioca flour, 4 parts of peracetic acid, 7 parts of sodium hydroxide, 11 parts of magnesium chloride, 4 parts of sodium hydroxyethyl sulfonate, and 24 parts of sodium silicate;

[0107] The preparation method is as follows:

[0108] (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water in a ratio of 1:1 to prepare an aqueous solution for standby;

[0109] (2) Add 50 parts of cassava flour to the reactor stirring, and atomize and spray 4 parts of peracetic acid solution for oxidation;

[0110] (3) Atomize and spray 7 parts of sodium hydroxide solution into the oxidized cassava flour during stirring for activation;

[0111] (4) Atomize and spray 11 parts of magnesium chloride solution into the activated cassava flour during stirring for catalysis;

[0112] (5) Heat the above mixture to 90 °C, add 4 parts of sodium hydroxyethyl sulfonate for esterification during stirring, stir for 160 min to form a hydroxyethyl copolymer. After cooling to room temperature, add 24 parts of sodium silicate, stir evenly, and pulverize to obtain the product.

[0113] Example 4.

[0114] Dissolve the pulverized coal granulation solidifying material in water to form a pulverized coal granulation solidifying material solution with a content of 8%. Use a high-pressure spraying device to spray the pulverized coal granulation solidifying material solution into the pulverized coal collector or dust removal tower, so that it is in close contact with the pulverized coal in the hot air. Under the action of centrifugal force, by changing the characteristics of the pulverized coal, the granulation functions and physical and chemical effects such as wetting, binding, and agglomeration of the pulverized coal are carried out, so that the pulverized coal agglomerates into particles. With the action of the countercurrent hot air, the pulverized coal particles settle in the finished product bin during the process of increasing and drying.

[0115] The raw material ratio of the pulverized coal granulation solidifying material solution with a content of 8% is as follows:

[0116] Prepare the raw materials in parts by mass:

[0117] 45 parts of cassava flour, 5 parts of peracetic acid, 8 parts of sodium hydroxide, 12 parts of magnesium chloride, 5 parts of sodium hydroxyethyl sulfonate, 25 parts of sodium silicate;

[0118] The preparation method is as follows:

[0119] (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water in a ratio of 1:1 to prepare an aqueous solution for standby;

[0120] (2) Add 45 parts of cassava flour to the reactor stirring, and atomize and spray 5 parts of peracetic acid solution for oxidation;

[0121] (3) Atomize and spray 8 parts of sodium hydroxide solution into the oxidized cassava flour during stirring for activation;

[0122] (4) Atomize and spray 12 parts of magnesium chloride solution into the activated cassava flour during stirring for catalysis;

[0123] (5) Heat the above mixture to 90 °C, add 5 parts of sodium hydroxyethyl sulfonate for esterification during stirring, stir for 160 min to form a hydroxyethyl copolymer. After cooling to room temperature, add 25 parts of sodium silicate, stir evenly, and pulverize to obtain the product.

[0124] The application effects of Examples 1 - 4 of the present invention are as follows:

[0125] Project Name Example 1 Example 2 Example 3 Example 4 Solution Concentration (%) 8.0 8.0 8.0 8.0 Coal Powder Particle Size before Pelletizing (mm) 0～0.15 0～0.15 0～0.15 0～0.15 Coal Powder Particle Size after Pelletizing (mm) 3～22 3～23 3～28 3～30 Coal Powder Pelletizing Molding Rate (parts) ＞80 ＞91 ＞95 ＞96 Dry Particle Strength (N, Φ5 - 15mm) 87 92 93 95

[0126] It can be seen from this that the particle size of pulverized coal after granulation in Examples 1 - 4 has been greatly improved, and the granulation forming rate of pulverized coal is above 80%, fully meeting the requirements of the granulation forming rate, and can be fully applied industrially. The strength of dried particles also meets the application requirements. Among the raw materials of the present invention, the higher the pH value, the greater the viscosity, the better the forming rate during application, the larger the particle size of pulverized coal after granulation, and the stronger the strength of dried particles. From the comprehensive performance, the effect of Example 4 is the best.

[0127] In terms of the technical solution of the present invention, there is no prior art for reference; in terms of application, the process of the present invention is simple, and the pulverized coal collection and granulation can be realized by transforming the original desulfurization tower and dust removal tower. Therefore, the present invention has obvious advantages in promoting the pulverized coal collection, long-distance storage and transportation, preventing spontaneous combustion, controlling coal dust pollution and industrial application in the drying process of low-rank coals such as lignite and coal slime.

[0128] In the present invention, the main improvements are in the overall connection, pulverized coal granulation and solidification materials, and operation methods. Therefore, the description of the control system is omitted. For example, after the work such as the inlet of pulverized coal dust and flue gas, the spraying of the centrifugal atomizer, and the stirring of the liquid preparation system is completed, it can be automatically controlled or manually controlled by buttons. The control system can be opened and closed, and can also transmit signals to the solenoid valve for independent opening and closing.

[0129] The present invention provides a pulverized coal collection and granulation device in the drying process of lignite and coal slime, which has a simple overall structure, small running resistance, no filter bag, no blockage, high pulverized coal collection efficiency, and is safe and stable. The present invention solves many problems such as traditional pulverized coal collection pollution, difficult granulation, spontaneous combustion and explosion, and inconvenient long-distance transportation and storage.

[0130] The present invention has the characteristics of simple overall structure, high pulverized coal collection rate, large coal particles, no filter bag, no blockage and spontaneous combustion, high purification rate, and safe operation.

[0131] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation of the present invention. After those skilled in the art have read the above content, various modifications and substitutions of the present invention will be obvious. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims

1. A pulverized coal collection and granulation device during the upgrading process of low-rank coal, characterized in that, It includes a tower body (1), a flue gas inlet (2), a flue gas outlet (3), a cleaning system (4), a liquid preparation system (5), a centrifugal atomizer (6), a conical centrifugal screen (7), a cyclone plate (8), a conical finished product bin (9), and a discharger (10); The flue gas inlet (2) is arranged at the lower end outside the tower body (1), and the flue gas outlet (3) is arranged at the top of the tower body (1); The centrifugal atomizer (6) is arranged at the upper end inside the tower body (1) above the flue gas inlet (2). The upper end of the centrifugal atomizer (6) is provided with a conical centrifugal screen (7). The upper end of the conical centrifugal screen (7) is provided with a cyclone plate (8). The upper end of the cyclone plate (8) is provided with a spray head, and the spray head is connected to the cleaning system (4) arranged outside the tower body (1); The centrifugal atomizer (6) is connected to the liquid preparation system (5) arranged outside the tower body (1), and a pulverized coal granulation and solidification material solution with a content of 8% is added to the liquid preparation system (5); The conical finished product bin (9) is arranged at the lower end inside the tower body (1) below the centrifugal atomizer (6), and the discharger (10) is arranged at the lower end of the conical finished product bin (9); The preparation method of the pulverized coal granulation and solidification material is as follows: Prepare raw materials in parts by mass: 45 - 65 parts of tapioca flour, 2 - 5 parts of peracetic acid, 5 - 8 parts of sodium hydroxide, 6 - 12 parts of magnesium chloride, 2 - 5 parts of sodium hydroxyethyl sulfonate, 20 - 25 parts of sodium silicate; The preparation method is as follows: (1) Dissolve peracetic acid, sodium hydroxide, magnesium chloride, and sodium hydroxyethyl sulfonate in water at a ratio of 1:1 to form aqueous solutions for standby; (2) Add 45 - 65 parts of tapioca flour to the reaction kettle under stirring, and atomize and spray 2 - 5 parts of peracetic acid solution for oxidation; (3) Atomize and spray 5 - 8 parts of sodium hydroxide solution into the oxidized tapioca flour under stirring for activation; (4) Atomize and spray 6 - 12 parts of magnesium chloride solution into the activated tapioca flour under stirring for catalysis; (5) Heat the above - catalyzed tapioca flour to 90 °C, add 2 - 5 parts of sodium hydroxyethyl sulfonate for esterification under stirring, stir for 160 min to form a hydroxyethyl copolymer. After cooling to room temperature, add 20 - 25 parts of sodium silicate, stir evenly, and pulverize to obtain the product; Then; (1) Introduce pulverized coal and flue gas to the flue gas inlet (2) of the tower body (1), and simultaneously start the centrifugal atomizer (6) and the liquid preparation system (5) in sequence; (2) Spray and atomize the pulverized coal granulation and solidification material solution prepared by the liquid preparation system (5) into the pulverized coal and flue gas in the tower body (1) through the centrifugal atomizer (6); (3) Through the process of collision, wetting, adhesion, and condensation between the pulverized coal granulation and solidification material solution by high - pressure spray atomization and the pulverized coal and flue gas, the pulverized coal is agglomerated into pulverized coal particles. As the pulverized coal particles settle during the process of increasing in size and weight, they are then dried by the high - temperature flue gas and settle in the conical finished product bin (9); (4) The small particles agglomerated in the tower body (1) rise with the flue gas, are filtered by the conical centrifugal screen (7), the small particles are cyclically agglomerated into large particles that increase in size and weight, and then are dried by the high - temperature flue gas and settle in the conical finished product bin (9); The flue gas filtered by the conical centrifugal sieve (7) enters the cyclone plate (8) for gas-solid separation. The purified flue gas is discharged from the flue gas outlet (3), and the separated fine particles sink and then participate in the circulating granulation again.

2. The pulverized coal collection and granulation device in the low-rank coal upgrading process according to claim 1, characterized in that, The peracetic acid described is anhydrous peracetic acid; the sodium silicate is powdered instant sodium silicate; the magnesium chloride is anhydrous magnesium chloride.

3. A pulverized coal collection and granulation device in the process of low-rank coal upgrading according to claim 1, characterized in that, 65 parts of tapioca flour, 2 parts of peracetic acid, 5 parts of sodium hydroxide, 6 parts of magnesium chloride, 2 parts of sodium hydroxyethyl sulfonate, 20 parts of sodium silicate.

4. A pulverized coal collection and granulation device during low-rank coal upgrading according to claim 1, characterized in that, 58 parts of tapioca flour, 3 parts of peracetic acid, 6 parts of sodium hydroxide, 8 parts of magnesium chloride, 3 parts of sodium hydroxyethyl sulfonate, 22 parts of sodium silicate.

5. A pulverized coal collection and granulation device during low-rank coal upgrading according to claim 1, characterized in that, 50 parts of tapioca flour, 4 parts of peracetic acid, 7 parts of sodium hydroxide, 11 parts of magnesium chloride, 4 parts of sodium hydroxyethyl sulfonate, 24 parts of sodium silicate.

6. A pulverized coal collection and granulation device in the low-rank coal upgrading process according to claim 1, characterized in that, 45 parts of the tapioca flour described, 5 parts of peracetic acid, 8 parts of sodium hydroxide, 12 parts of magnesium chloride, 5 parts of sodium hydroxyethyl sulfonate, 25 parts of sodium silicate.

7. A pulverized coal collection and granulation device during low-rank coal upgrading according to claim 1, characterized in that, The flue gas inlet (2) is placed on the tower body (1) at an upward inclination of 45°.

8. A pulverized coal collection and granulation device during low-rank coal upgrading according to claim 1, characterized in that The liquid preparation system (5) includes a liquid preparation shell, in which a stirrer and a submersible slurry pump are installed. The liquid preparation shell is connected to the centrifugal atomizer (6) through a liquid delivery pipeline.

9. A pulverized coal collection and granulation device during low-rank coal upgrading according to claim 1, characterized in that, The cleaning system (4) includes a cleaner placed outside the tower body (1). A water pump is installed inside the cleaner, and the water pump is connected to a spray head placed above the cyclone plate (8) through a water pipe.

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