A stepped air inlet multi-channel residue discharging chlorination furnace

Abstract

This utility model belongs to the field of chlorination furnace technology, specifically relating to a stepped air intake and multi-channel slag discharge chlorination furnace. It includes a chlorination furnace shell, with a three-stage air intake system at the bottom. This system comprises a first-stage air intake pipe, a second-stage air intake pipe, and a third-stage air intake pipe, located at the bottom, middle, and top of the three-stage system, respectively. The bottom of the chlorination furnace shell has a main slag discharge port, a first side slag discharge port, and a second side slag discharge port. The main slag discharge port is located at the center of the furnace bottom, while the first and second side slag discharge ports are located on the left and right sides of the main slag discharge port, respectively. The interior of the chlorination furnace shell is lined with bricks, and an elastic lining is provided between the brick lining and the inner wall of the chlorination furnace shell. This utility model can improve gas-solid mixing efficiency and slag discharge reliability, and is suitable for titanium-containing raw materials with high calcium and magnesium content and a wide particle size range, resulting in a chlorination furnace lifespan superior to traditional chlorination furnaces.

Description

Technical Field

[0001] This utility model belongs to the field of chlorination furnace technology, specifically relating to a chlorination furnace with stepped air intake and multi-channel slag discharge. Background Technology

[0002] The chlorination process in the fluidized bed involves using fine-particle titanium-rich materials and solid carbonaceous (petroleum coke) reducing agents in a fluidized state under high temperature and chlorine gas flow to produce titanium tetrachloride. The reaction is typically carried out in a steel-lined, refractory-cooled furnace with an external water-cooled jacket. Titanium-rich materials such as rutile ore or high-titanium slag are ground and added to the chlorination furnace from above the fluidized bed along with a certain proportion of petroleum coke. Chlorine gas is added from the bottom of the furnace, and the chlorination reaction is carried out continuously at 925–1010°C until oxides of iron, silicon, vanadium, calcium, magnesium, and other metals are converted into their corresponding chlorides, which then leave the chlorination furnace with the gas.

[0003] However, in actual production, stable operation of the chlorination furnace is the fundamental prerequisite for ensuring normal production. But with the current decline in the quality of titanium raw materials, the content of elements such as calcium and magnesium, which have a significant impact on the operation of the chlorination furnace, is increasing, and the particle size of the raw materials is becoming finer, which is not conducive to the normal operation of the chlorination furnace. Traditional chlorination furnaces use all bottom air intake or all side air intake, resulting in uneven gas-solid mixing and low reaction efficiency. Furthermore, the single slag discharge port at the bottom of traditional chlorination furnaces is easily blocked by the lining bricks worn off inside the furnace, and is also easily blocked by sintered material. Forced unblocking can easily cause mechanical damage to the lining bricks, affecting their lifespan.

[0004] Therefore, the applicant designed a chlorination furnace with stepped air intake and multi-channel slag discharge to solve the above problems. Utility Model Content

[0005] To address the aforementioned deficiencies in existing technologies, this utility model provides a chlorination furnace with a stepped air intake and multi-channel slag discharge system. The furnace includes a furnace shell, with an upper end cap at the top and a lower end cap at the bottom. An exhaust port is located at the top of the furnace shell, and a feed inlet is located on the side. A three-stage air intake system is located at the bottom of the furnace shell, comprising a first-stage air intake pipe, a second-stage air intake pipe, and a third-stage air intake pipe. The first-stage air intake pipe is located at the bottom of the three-stage system and is used for strong turbulent mixing. The second-stage air intake pipe is located in the middle of the three-stage system and is used for breaking up agglomerates. The chlorination furnace has a three-stage inlet pipe located at the top of the three-stage inlet system for fluidizing coarse particles and a main slag discharge port, a first side slag discharge port, and a second side slag discharge port at the bottom. The main slag discharge port is located at the center of the furnace bottom and usually discharges broken lining bricks and large sintered materials. The first side slag discharge port is located to the left of the main slag discharge port and usually discharges mixed materials. The second side slag discharge port is located to the right of the main slag discharge port and is higher than the first side slag discharge port. It usually discharges fine particulate furnace charge, which can be reused as raw material. The interior of the chlorination furnace shell is lined with a brick layer, and an elastic lining is installed between the brick layer and the inner wall of the chlorination furnace shell.

[0006] Optionally, the first-stage intake pipe has an angle of 25-35° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 25-30 m / s; the second-stage intake pipe has an angle of 40-50° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 15-20 m / s; and the third-stage intake pipe has an angle of 55-65° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 8-10 m / s.

[0007] Optionally, the nominal diameter of the main slag discharge port, the first side slag discharge port, and the second side slag discharge port is DN250mm, and the main slag discharge port is equipped with a hydraulic gate valve and a silicon carbide bushing.

[0008] Specifically, nitrogen purging devices (pressure 0.6-1.0 MPa) are installed at both the main slag discharge port and the first side slag discharge port, while a negative pressure suction device (vacuum degree ≥ -50 kPa) is installed at the second side slag discharge port. The first side slag discharge port is used for side slag discharge. When the bottom material or lining bricks become too thick after prolonged furnace operation, causing slag discharge obstruction, nitrogen can be used to clear the obstruction through a quick-release flange and nitrogen nozzles (0.8 MPa) arranged in a ring at the first side slag discharge port. The second side slag discharge port is used to discharge finer furnace materials. This portion of the furnace material, after simple screening, can be directly reused as raw material for the chlorination process, improving titanium yield. If clearing the obstruction at the first side slag discharge port fails, negative pressure suction can be performed through a negative pressure interface and the negative pressure suction device. Through these slag discharge methods, harmful calcium, magnesium, and silicon in the furnace bed can be promptly discharged outside the furnace, improving the applicability of the raw materials.

[0009] Optionally, the elastic liner is made of elastic microporous refractory fiber with a thickness of 8-15 mm and a porosity of ≥80%.

[0010] Specifically, it is used to resist thermomechanical stress impacts.

[0011] This invention also includes other components that enable the normal operation of a chlorination furnace with a stepped air intake and multi-channel slag discharge, all of which are conventional techniques in the art. Furthermore, any devices or components not specified in this invention employ conventional techniques in the art.

[0012] The working principle of this utility model is as follows: when the main slag discharge port is detected to be blocked, the hydraulic gate valve is closed and the first side slag discharge port is opened. The slag is cleared by a nitrogen purging device. If the clearing fails, the second side slag discharge port is opened and negative pressure suction is performed by a negative pressure suction device.

[0013] The beneficial effects of this utility model are:

[0014] (1) Breakthrough in mixing efficiency: The gas-solid contact area is increased by 40%, and the TiO2 conversion rate is >95% compared with traditional furnaces (conversion rate ≤85%).

[0015] (2) Slag discharge reliability: The blockage treatment time is shortened from 4 hours to 0.5 hours, and the annual production capacity is increased by 1200 hours.

[0016] (3) The life of the furnace lining is doubled: the elastic lining absorbs 90% of the thermal stress, and the replacement cycle of the lining bricks is extended to 24 months.

[0017] (4) Efficient utilization of resources: TiO2 residue in slag is less than 3%, saving RMB 8 million in titanium raw material costs per 10,000 tons of production capacity per year. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0020] In the diagram: 1. Chlorination furnace shell, 2. Upper head, 3. Lower head, 4. Feed inlet, 5. First-stage air inlet pipe, 6. Second-stage air inlet pipe, 7. Third-stage air inlet pipe, 8. Main slag discharge port, 9. First side slag discharge port, 10. Second side slag discharge port, 11. Lining brick layer. Detailed Implementation

[0021] The present invention will now be clearly described with reference to the accompanying drawings and specific embodiments. This description is merely for explaining the present invention and is not intended to limit it. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art based on the embodiments of the present invention without inventive effort to obtain all other embodiments should be included within the protection scope of the present invention.

[0022] Example

[0023] like Figure 1 As shown in the figure, this utility model embodiment provides a chlorination furnace with a stepped air intake and multi-channel slag discharge, including a chlorination furnace shell 1, an upper end cap 2 provided at the upper part of the chlorination furnace shell 1, and a lower end cap 3 provided at the lower part of the chlorination furnace shell 1; an exhaust port is provided at the top of the chlorination furnace shell 1, and a feed inlet 4 is provided on the side of the chlorination furnace shell 1; a three-stage air intake system is provided at the bottom of the chlorination furnace shell 1, the three-stage air intake system including a first-stage air intake pipe 5, a second-stage air intake pipe 6, and a third-stage air intake pipe 7. The first-stage air intake pipe 5 is located at the bottom of the three-stage air intake system and is used for strong turbulent mixing; the second-stage air intake pipe 6 is located in the middle of the three-stage air intake system and is used for breaking up clumps and fluidizing coarse particles; the third-stage air intake pipe 7 is located at the bottom of the three-stage air intake system. The top layer is used for fluidizing fine particles; the bottom of the chlorination furnace shell 1 is provided with a main slag discharge port 8, a first side slag discharge port 9, and a second side slag discharge port 10. The main slag discharge port 8 is located at the center of the furnace bottom and usually discharges broken lining bricks and large sintered materials. The first side slag discharge port 9 is located to the left of the main slag discharge port 8 and usually discharges mixed materials. The second side slag discharge port 10 is located to the right of the main slag discharge port 8 and is positioned higher than the first side slag discharge port 9. It usually discharges fine particulate furnace materials, which can be reused as raw materials. The interior of the chlorination furnace shell 1 is provided with a lining brick layer 11, and an elastic microporous refractory fiber layer with a thickness of 8-15mm and a porosity ≥80% is provided between the lining brick layer 11 and the inner wall of the chlorination furnace shell 1 to resist thermomechanical stress impact.

[0024] Specifically, the first-stage air intake pipe 5 has an angle of 30° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 25-30 m / s; the second-stage air intake pipe 6 has an angle of 45° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 15-20 m / s; and the third-stage air intake pipe 7 has an angle of 60° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 8-10 m / s.

[0025] In addition, the nominal diameter of the main slag discharge port 8, the first side slag discharge port 9, and the second side slag discharge port 10 is DN250mm. The main slag discharge port 8 is equipped with a hydraulic gate valve and a silicon carbide bushing. Nitrogen purging devices (pressure 0.6-1.0MPa) are installed at the main slag discharge port 8 and the first side slag discharge port 9, and a negative pressure suction device (vacuum degree ≥-50kPa) is installed at the second side slag discharge port 10.

[0026] Understandably, the first side slag discharge port 9 is used for side slag discharge. When the bottom material or lining bricks become too thick after prolonged furnace operation, causing poor slag discharge, nitrogen can be used to clear the blockage through quick-release flanges and nitrogen nozzles (0.8 MPa) arranged in a ring at the first side slag discharge port 9. The second side slag discharge port 10 is used to discharge finer furnace materials. This portion of the furnace material, after simple screening, can be directly reused as raw material for the chlorination process, improving titanium yield. If clearing the blockage at the first side slag discharge port 9 fails, negative pressure suction can be performed through a negative pressure interface and a negative pressure suction device. Through the above slag discharge methods, harmful calcium, magnesium, and silicon in the bed can be discharged to the outside of the furnace in a timely manner, thereby improving the applicability of the raw materials.

[0027] The working principle of this utility model is as follows: when the main slag discharge port 8 is detected to be blocked, the hydraulic gate valve is closed and the first side slag discharge port 9 is opened. The slag is cleared by a nitrogen purging device. If the clearing fails, the second side slag discharge port 10 is opened and negative pressure suction is performed by a negative pressure suction device.

[0028] The embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A chlorination furnace with stepped air intake and multi-channel slag discharge, comprising a chlorination furnace shell, characterized in that: The upper part of the chlorination furnace shell is provided with an upper end cap, and the lower part of the chlorination furnace shell is provided with a lower end cap; the bottom of the chlorination furnace shell is provided with a three-stage air intake system, which includes a first-stage air intake pipe, a second-stage air intake pipe, and a third-stage air intake pipe. The first-stage air intake pipe is located at the bottom of the three-stage air intake system, the second-stage air intake pipe is located in the middle of the three-stage air intake system, and the third-stage air intake pipe is located at the top of the three-stage air intake system; the bottom end of the chlorination furnace shell is provided with a main slag discharge port, a first side slag discharge port, and a second side slag discharge port. The main slag discharge port is located at the center of the furnace bottom, the first side slag discharge port is located to the left of the main slag discharge port, and the second side slag discharge port is located to the right of the main slag discharge port and is positioned higher than the first side slag discharge port; the interior of the chlorination furnace shell is provided with a brick lining layer, and an elastic lining layer is provided between the brick lining layer and the inner wall of the chlorination furnace shell.

2. The chlorination furnace with stepped air intake and multi-channel slag discharge according to claim 1, characterized in that: The first-stage intake pipe has an angle of 25-35° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 25-30 m / s; the second-stage intake pipe has an angle of 40-50° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 15-20 m / s; the third-stage intake pipe has an angle of 55-65° with the vertical plane, a diameter of 50 mm, and a gas flow velocity of 8-10 m / s.

3. The chlorination furnace with stepped air intake and multi-channel slag discharge according to claim 2, characterized in that: The nominal diameters of the main slag discharge port, the first side slag discharge port, and the second side slag discharge port are all DN250mm, and the main slag discharge port is equipped with a hydraulic gate valve and a silicon carbide bushing.

4. The chlorination furnace with stepped air intake and multi-channel slag discharge according to claim 3, characterized in that: The elastic lining is made of elastic microporous refractory fiber layer with a thickness of 8-15mm and a porosity of ≥80%.

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