CN-121977351-A - Suspension grading and sectioning calcination system

CN121977351ACN 121977351 ACN121977351 ACN 121977351ACN-121977351-A

Abstract

The invention discloses a suspension grading sectional calcining system, which relates to the technical field of ore decomposition and comprises a material scattering box and a suspension furnace body, wherein the bottom end of the suspension furnace body is fixedly provided with a first-stage calciner, a second-stage calciner and a third-stage calciner from left to right respectively. The suspension grading and sectional calcining system is provided with the suspension furnace body, the first-stage calcining furnace, the second-stage calcining furnace and the third-stage calcining furnace, when the suspension grading and sectional calcining system is used, particles are graded by utilizing smoke, and when the sedimentation speed of a material with a certain critical particle size is smaller than the flow speed of the smoke, the material can be completely carried by the smoke to rise, and the material moves along with the smoke along the furnace body. The suspension furnace body is provided with a plurality of ascending sections and descending sections, and the flue gas is utilized for grading. The method realizes the efficient classified calcination of the fine ore with the grain size less than 5mm, and solves the problem that the existing suspension calcination process is required to grind and pretreat the fine ore with the grain size less than 5 mm.

Inventors

SHEN HAO
ZHANG LINJIN
PANG HUANJUN
HUANG XINJING
WANG DONG
TANG DAN
LI JIYE

Assignees

江苏中圣园科技股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260209

Claims (9)

1. The suspension grading and segmented calcining system comprises a material spreading box (1) and a suspension furnace body (2) and is characterized in that a first burner (3) is fixedly arranged on the left side of the suspension furnace body (2), a first-section calcining furnace (4), a second-section calcining furnace (5) and a third-section calcining furnace (6) are fixedly arranged at the bottom end of the suspension furnace body (2) from left to right, a second burner (7) is fixedly arranged at the front end of the second-section calcining furnace (5), a third burner (8) is fixedly arranged at the front end of the third-section calcining furnace (6), and a cyclone separator (9) is fixedly arranged on the right side of the suspension furnace body (2); The suspension furnace body (2) comprises a first uplink section (201), the first uplink section (201) is arranged above the one-section calciner (4), and a first downlink section (202), a second uplink section (203), a second downlink section (204) and a third uplink section (205) are sequentially arranged on the right side of the first uplink section (201).
2. A suspension classification and segmentation calcination system according to claim 1, and characterized in that the scattering box (1) and the first ascending section (201) are communicated, and the first burner (3) and the axis of the first ascending section (201) form an angle of 90 degrees.
3. The suspension classification and segmentation calcination system according to claim 1, wherein the tops of the first uplink section (201) and the first downlink section (202) are connected through an arc transition pipeline to form an inverted U-shaped flue gas channel.
4. A suspension classification and segmentation calcination system according to claim 1, wherein the bottoms of the first descending section (202) and the second ascending section (203) are connected through an arc transition pipeline to form a U-shaped flue gas channel, and the bottoms of the U-shaped flue gas channel are connected with the two-stage calciner (5).
5. The suspension classification and segmentation calcination system according to claim 1, wherein the tops of the second uplink section (203) and the second downlink section (204) are connected through an arc transition pipeline to form an inverted U-shaped flue gas channel.
6. A suspension classification and segmentation calcination system according to claim 1, wherein the bottoms of the second downstream section (204) and the third upstream section (205) are connected through an arc transition pipeline to form a U-shaped flue gas channel, and the bottoms of the U-shaped flue gas channel are connected with a three-stage calciner (6).
7. A suspension classification and segmentation calcination system according to claim 1, wherein the top end of the third ascending section (205) is connected with the cyclone separator (9) through an arc transition pipeline, and the third ascending section (205) and the cyclone separator (9) are communicated.
8. The suspension classification and segmentation calcination system according to claim 1, wherein the upper end and the lower end of the first uplink section (201), the first downlink section (202), the second uplink section (203), the second downlink section (204) and the third uplink section (205) are flush, and the interiors of the first uplink section (201), the first downlink section (202), the second uplink section (203), the second downlink section (204) and the third uplink section (205) are communicated.
9. A suspension classification staged calcination method as defined in any one of claims 1 to 5, comprising the steps of: S1, preheating materials, entering a suspension furnace body (2) from a material scattering box (1), descending the materials under inertial impact, carrying the materials to the upper side by lower high-temperature flue gas, generating high-temperature flue gas by a first burner (3) arranged below the material scattering box (1), and burning fuel after air distribution to generate high-temperature flue gas; S2, the materials entering the suspension furnace body (2) have obvious particle size difference, the materials with small particle size are completely carried by the flue gas, the particles are classified by the flue gas at the moment, when the sedimentation speed of the materials with a certain critical particle size is smaller than the flow rate of the flue gas, the materials can be completely carried by the flue gas to rise, the materials move forward along the furnace body along with the flue gas, and the sedimentation speed of the particles with large particle size is larger than the flow rate of the flue gas, the materials in the furnace are sedimented into a section of calciner (4) to be gradually accumulated; s3, a discharge hole and a discharge valve are arranged at the lower part of the first-stage calciner (4), the discharge speed of the material is controlled by the opening of the discharge valve, the reasonable material level of particles in the first-stage calciner (4) is maintained, and the material is ensured not to be excessively burnt or not to be burnt; S4, fine particles classified by utilizing the flue gas at the material scattering box (1) are carried by the flue gas and enter the first downlink section (202) after passing through the first uplink section (201), and rise again to enter the second uplink section (203) after the first downlink section (202) descends through the bent pipe. The flow direction of the flue gas is changed, the particles generate centrifugal force, and a part of particles are deposited at the turning position and enter a two-stage calciner (5) to be gradually accumulated; S5, the materials piled in the two-stage calciner (5) are subjected to radiation and convection heat transfer of combustion flue gas, gradually heated and decomposed, a discharge port and a discharge valve are arranged at the lower part of the two-stage calciner (5), the discharge speed of the materials is controlled by the opening of the discharge valve, the reasonable material level of particles in the two-stage calciner (5) is maintained, and the materials are ensured not to be excessively burnt or not to be burnt; S6, fine particles are classified again when entering a third ascending section (205) after passing through a second descending section (204), part of the fine particles enter a three-section calciner (6), flue gas generated by a third combustor (8) is heated and calcined, and reasonable material level is controlled to ensure that the heated and calcined materials are completed; S7, enabling the fine particle materials subjected to multiple classification to enter a cyclone separator (9) through an outlet of a suspension furnace body (2), performing gas-solid separation in the cyclone separator (9), discharging fine particle finished products into a cooling system through a lower outlet, and discharging flue gas into a preheating system through an upper air outlet to preheat the materials.

Description

Suspension grading and sectioning calcination system Technical Field The invention relates to the technical field of ore decomposition, in particular to a suspension grading and segmented calcining system. Background Kilns commonly used in ore calcination and decomposition processes include sleeve kilns, double-hearth kilns, rotary kilns, and the like. Wherein, the shaft kiln such as sleeve kiln, double-chamber kiln, etc. is suitable for calcining 30-80mm, 40-90mm, etc. larger lump ores, while the rotary kiln can be used for treating 5-30mm medium granularity materials. However, due to limitations of mine geology and mining processes, the yield of lump ore is generally only 65% -70%, resulting in a large amount of small-particle ore below 5mm being difficult to be effectively utilized by existing calcination systems. These fine particles are usually deposited around the mine area by being discarded, which not only causes resource waste, but also brings adverse effects to the surrounding environment. In recent years, suspension calcination technology has been gradually applied to the field of ore decomposition as a new fluidized calcination method. The technology utilizes the ground fine mineral powder to uniformly disperse the fine mineral powder in high-temperature flue gas, thereby realizing rapid heat transfer and high-efficiency decomposition. In order to ensure that the material is fully suspended in the flue gas and moves along with the air flow, suspension calcination generally requires that the particle size of the raw material is controlled below 80 mu m so as to complete the reaction in a very short time. However, in order to meet the particle size requirement, a grinding pretreatment is generally required for raw materials of 5mm or less. This procedure not only increases equipment investment and site requirements, but also brings additional energy consumption burden. Therefore, development of a process method and matched equipment capable of directly calcining fine ore with the grain size of less than 5mm has important practical significance. The technology is hopeful to omit a grinding link, optimize the whole process, save energy consumption, reduce investment and operation cost, realize high-efficiency and high-value utilization of ore resources in the full grain size range, and realize the aims of cost reduction, efficiency enhancement and green production by power-assisted enterprises. At present, a novel suspension classification and segmentation calcining system is provided for solving the problems. Disclosure of Invention The invention aims to provide a suspension grading and segmented calcining system which solves the problem that the existing suspension calcining technology proposed in the background art needs to grind and pretreat fine ore with the particle size less than 5 mm. The suspension grading and sectional calcining system comprises a material scattering box and a suspension furnace body, wherein a first burner is fixedly arranged on the left side of the suspension furnace body, a first-stage calcining furnace, a second-stage calcining furnace and a third-stage calcining furnace are respectively and fixedly arranged at the bottom end of the suspension furnace body from left to right, a second burner is fixedly arranged at the front end of the second-stage calcining furnace, a third burner is fixedly arranged at the front end of the third-stage calcining furnace, and a cyclone separator is fixedly arranged on the right side of the suspension furnace body. The suspension furnace body comprises a first uplink section, the first uplink section is arranged above the first section calciner, and a first downlink section, a second uplink section, a second downlink section and a third uplink section are sequentially arranged on the right side of the first uplink section. As a further technical scheme of the invention, the scattering box and the interior of the first ascending section are communicated, and the first burner and the axis of the first ascending section form an angle of 90 degrees. As a further technical scheme of the invention, the tops of the first uplink section and the first downlink section are connected through an arc transition pipeline to form an inverted U-shaped flue gas channel. As a further technical scheme of the invention, the bottoms of the first descending section and the second ascending section are connected through an arc transition pipeline to form a U-shaped flue gas channel, and the bottoms of the U-shaped flue gas channel are connected with the two-section calciner. As a further technical scheme of the invention, the tops of the second uplink section and the second downlink section are connected through an arc transition pipeline to form an inverted U-shaped flue gas channel. As a further technical scheme of the invention, the bottoms of the second descending section and the third ascending section are connected through an arc transition pipeline to f