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CN-122015492-A - Closed superhigh temperature fluidization calcining pot

CN122015492ACN 122015492 ACN122015492 ACN 122015492ACN-122015492-A

Abstract

The invention discloses a three-dimensional circulation closed-loop type high-temperature calcination device and process, and belongs to the technical field of mineral fertilizer calcination. The device comprises a vertical sealed calcination tank, a plurality of vertical air distribution blast pipes, a central exhaust pipe and a variable-frequency auger, wherein the air distribution blast pipes and the central exhaust pipe are uniformly distributed with micropores to form a three-dimensional circulation structure with external air supply and internal exhaust, so that a 5-meter high-material layer is uniformly heated. The process adopts 1250 ℃ for sealing calcination for 1 hour, stops the furnace for heat preservation for 1 hour, and then pumps out high-temperature waste heat through a central exhaust tube for preheating the material of the other calcination tank, thereby realizing multi-furnace linkage and waste heat cascade utilization. The invention can control the calcining temperature difference within +/-20 ℃, has the characteristics of sealing, environmental protection, uniform heating, full reaction, high residual heat utilization rate and the like, and is particularly suitable for the industrialized high-temperature calcining production of the small particle materials of the silicon-calcium-magnesium fertilizer.

Inventors

  • YAN WEIMIN

Assignees

  • 闫卫民

Dates

Publication Date
20260512
Application Date
20260315

Claims (9)

  1. 1. A three-dimensional circulation closed-loop type high-temperature calcination device is characterized by comprising a vertical sealed calcination tank, wherein at least seven air distribution blast pipes are vertically arranged in the sealed calcination tank, a plurality of micropores are uniformly distributed on the pipe wall of the air distribution blast pipes and are used for three-dimensionally spraying hot air to a material layer in the tank, an exhaust pipe is arranged in the center of the sealed calcination tank, the diameter of the exhaust pipe is 200mm, the pipe wall is also fully provided with micropores and is used for pumping high-temperature flue gas from the center area of the material layer, the hot air sent out by the air distribution blast pipes forms a three-dimensional flow field in the tank, hot air pushing and the negative pressure action of the center exhaust pipe jointly form a hot air circulation, the whole sealed calcination tank is of a closed structure, no external straight exhaust port is formed, and the high-temperature flue gas enters a waste heat recovery or cross-furnace preheating system after being pumped out by the exhaust pipe, so that a full-sealed closed-loop flue gas circulation system is formed.
  2. 2. The device according to claim 1, wherein the opening ratios of the air distribution blast pipes are uniformly distributed along the height direction of the tank body, so that three-dimensional hot air penetration of the 5-meter-height material layer can be realized, and local overheating or cold spot formation is avoided.
  3. 3. The device according to claim 1, wherein the air draft amount of the central air draft tube is matched with the air supply amount of the air distribution air supply pipe, so that the thermal balance state of micro positive pressure or micro negative pressure is maintained in the tank, and the exhaust gas is prevented from leaking out and the circulation uniformity of hot air flow is promoted.
  4. 4. The device according to claim 1, wherein at least three augers are arranged in the sealed calcination tank, the augers are driven by variable frequency, the rotating speed range is 10-35 r/min, and the augers are used for three-dimensionally stirring materials in the high-temperature calcination process, so that the materials form microfluidization in hot air flow, and the temperature difference at the calcination temperature of 1250 ℃ is controlled within +/-20 ℃.
  5. 5. The device according to claim 1, wherein the sealed calcining tank and another sealed calcining tank with the same structure form a linkage system, and the high-temperature waste heat hot air of the furnace is conveyed to another furnace through a central exhaust pipe for preheating the materials of the next furnace.
  6. 6. The three-dimensional circular flow closed-loop type high-temperature calcination process is characterized by comprising the following steps of: 1) Loading the small particle materials of the silicon-calcium-magnesium fertilizer into a vertical sealed calcination tank, and controlling the height of a material layer to be 2.5-3 meters; 2) Injecting 1200-1300 ℃ hot air into the tank through seven air distribution blast pipes, and enabling the hot air to penetrate through the 5-meter material layer in a three-dimensional manner through micropores; 3) The central exhaust pipe is used for exhausting high-temperature flue gas in the tank by negative pressure, so that the hot gas flows around the central exhaust pipe are converged to form a three-dimensional circulation; 4) Stirring the auger at variable frequency rotation speed to enable the material to be microfluidized in hot air flow and heated uniformly; 5) Heating the material to 1250 ℃, and performing seal calcination for 1 hour; 6) Stopping the furnace after calcining, and preserving the heat for 1 hour in a fully sealed state to ensure that the materials react fully and have uniform temperature; 7) After the heat preservation is finished, high-temperature waste heat air in the tank is extracted through an exhaust pipe with the center of 200mm, the waste heat air is introduced into another sealed calcining tank, and the next furnace of silicon-calcium-magnesium fertilizer materials is preheated; 8) The furnace enters a sealing cooling stage after the waste heat is extracted, and is discharged after cooling is finished, and the next furnace is preheated and then rapidly rises to the calcining temperature, so that multi-furnace linkage and waste heat cascade utilization are realized.
  7. 7. The process according to claim 6, wherein the calcination temperature is 1250 ℃, the calcination time is 1 hour, the heat preservation time is 1 hour, the temperature difference between the inside and the outside of the material is further reduced by stopping the furnace for heat preservation, and the calcination uniformity is ensured.
  8. 8. The process of claim 6, wherein the waste heat hot air is intensively extracted through the central exhaust pipe, is not discharged to the outside, is completely used for preheating another furnace material, and realizes full sealing, zero leakage and high efficiency and energy saving.
  9. 9. The process according to claim 6, wherein the material of the next furnace after being preheated by the waste heat can be rapidly raised to 300-500 ℃ from room temperature, so that the heating time is shortened, and the fuel consumption is reduced.

Description

Closed superhigh temperature fluidization calcining pot Technical Field The invention relates to the technical field of high-temperature calcination of mineral fertilizers, in particular to a three-dimensional circular flow closed-loop type high-temperature calcination device and a three-dimensional circular flow closed-loop type high-temperature calcination process, which are particularly suitable for uniform calcination, sealed heat preservation and waste heat cross-furnace preheating utilization of small particle materials of a silicon-calcium-magnesium fertilizer at an ultrahigh temperature of 1250 ℃. Background Most of traditional silicon-calcium-magnesium fertilizer calcination equipment is of an open structure or a unidirectional air supply structure, and the following problems exist: 1. The deep bed material layer has large height, uneven hot air penetration, large temperature difference and unstable calcination quality; 2. High-temperature flue gas is directly discharged, waste heat is seriously wasted, and energy consumption is high; 3. the heat preservation process is omitted, the internal reaction of the materials is insufficient, and the materials are easy to be over-burned or under-burned; 4. the smoke is discharged in an unorganized way, the environmental protection is not up to standard; 5. the multi-furnace linkage and waste heat cascade utilization cannot be realized. Aiming at the defects, the invention realizes high-temperature uniform calcination and high-efficiency energy conservation through the integrated design of three-dimensional circulation air supply, central air draft, sealed calcination, timing heat preservation, waste heat cross-furnace preheating and the like. Disclosure of Invention 1. Technical problem to be solved 1. Realizing the temperature difference of small silicon-calcium-magnesium fertilizer particles with the height of 5 meters and the reserve of 50 tons at 1250 ℃ to be less than or equal to +/-20 ℃; 2. realize full-sealed calcination, no exhaust gas leakage, and meet the environmental protection requirement; 3. the heat preservation procedure after calcination is added, so that the material reaction is more sufficient and the quality is more stable; 4. realizes high-temperature waste heat recovery and is used for preheating the next furnace, thereby greatly reducing energy consumption. 2. Technical proposal Device part: -a vertical sealed calciner, wholly closed; Seven vertical air distribution blast pipes, namely, full-height densely distributed micropores and three-dimensional air supply; -a 200mm exhaust tube in the center, full-height densely distributed micropores and negative pressure exhaust; -a plurality of variable frequency augers for three-dimensional agitation of the material; multi-furnace linkage, waste heat conveying and preheating across furnaces. The process comprises the following steps: charging, three-dimensional circulation hot air heating, 1250 ℃ calcination for 1 hour, sealing and heat preservation for 1 hour, central air draft for recovering waste heat, waste heat feeding into another furnace for preheating, sealing, cooling and discharging of the furnace, and rapid heating and calcination of the next furnace. 3. Advantageous effects 1. The temperature is uniform, the temperature difference is less than or equal to +/-20 ℃ at 1250 ℃, and the quality of the finished product is stable; 2. The sealing environment-friendly structure is a totally-enclosed structure, and no dust and no smoke leak; 3. The reaction is complete, calcination is carried out for 1 hour and heat preservation is carried out for 1 hour, and the internal and external reactions of the materials are consistent; 4. the energy is extremely saved, the high-temperature waste heat is not discharged and is completely used for preheating the next furnace, and the comprehensive energy consumption is greatly reduced; 5. Continuous production, multi-furnace linkage, preheating, calcining, heat preservation and cooling circulation operation, and high efficiency. Drawings FIG. 1 is a schematic structural diagram of a three-dimensional circulation closed-loop type high-temperature calcination device according to the present invention. Detailed Description 1. Charging material And (3) loading the small silicon-calcium-magnesium fertilizer particles into a vertical sealed calcination tank, wherein the height of the material layer is controlled to be 2.5-3 meters. 2. Three-dimensional circulation heating Seven wind distribution blast pipes are filled with 1200-1300 ℃ hot wind, a central exhaust pipe is used for exhausting air synchronously to form a three-dimensional circulation, and a packing auger is used for frequency conversion stirring to enable materials to be microfluidized and heated uniformly. 3. High temperature calcination for 1 hour The temperature was stabilized at 1250 ℃ and the calcination was sealed for 1 hour. 4. Furnace shutdown and heat preservation for 1 hour Stopping h