Fluidized bed for reducing iron ore powder
By building the cyclone separator into the fluidized bed reactor and using the independent outlet of its discharge pipe to discharge fine particulate materials in a timely manner, the problem of fine particles not being discharged in a timely manner in the prior art is solved, and the fluidized bed reaction is improved The efficiency of the device and reduces the weight and cost of the device.
Patent Information
- Application Number
- CN202421035017.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-13
- Publication Date
- 2025-02-11
- Estimated Expiration
- 2034-05-13
AI Technical Summary
When the existing fluidized bed reduces iron ore powder, fine solid particles are easily carried out by gas, resulting in a large amount of space occupied by the cyclone separator, heavy equipment and high cost, and the fine particles cannot be discharged in time, reducing the fluidized bed reactor efficiency.
Built into the cyclone separator into the fluidized bed reactor. By setting up a built-in cyclone separator in the fluidized bed body, the fine particulate materials that have reached the preset reduction degree will be discharged in time by using the independent outlet of its discharge pipe to improve the reactor. efficiency.
Through the built-in cyclone separator, the equipment footprint and weight are reduced, the cost is reduced, and the efficiency of the fluidized bed reactor is improved by about 15 to 30%, while saving about 10 to 20%.
Smart Images
Figure CN222455084U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a fluidized bed for reducing iron ore powder, belonging to the technical field of ironmaking, and can also be used in the field of gas-solid reaction fluidized beds in other industries. Background Art
[0002] At present, the metallurgical industry is in the early stage of actively developing hydrogen metallurgical technology and equipment. Whether it is direct reduction or molten reduction, iron ore needs to go through a reduction process. There are many methods for reducing iron ore. According to the type of reduction reactor, it can be divided into rotary kiln, vertical furnace and fluidized bed. Among various technical routes, the gas-solid reduction reaction of hydrogen or a mixed gas of hydrogen and carbon monoxide with iron ore powder through a fluidized bed is a high-reduction efficiency and more promising technical route.
[0003] In the process of reducing iron ore in a fluidized bed, fine solid particles are inevitably carried out by the gas. Therefore, the outlet of the fluidized bed is generally connected to a cyclone separator to recover the fine solid particles. In this way, the space occupied by the entire system will be greatly increased. In addition, the cyclone separator also needs to be insulated, resulting in a larger overall weight and higher cost of the equipment.
[0004] In order to reduce heat dissipation, occupy less space, and simplify equipment connection of the cyclone dust collector supporting the fluidized bed, the cyclone dust collector can be set inside the fluidized bed. However, since the solid phase outlet of the cyclone separator is located inside the fluidized bed, the fine particles separated can only return to the fluidized bed layer again. A small part of the fine particles returned to the fluidized bed layer are discharged out of the bed through the discharge port of the fluidized bed together with the coarse particles, and most of the rest continue to circulate in the fluidized bed, so that the fine particles that have reached the preset reduction degree cannot be discharged out of the bed in time, resulting in reduced efficiency and increased energy consumption of the fluidized bed reactor. Utility Model Content
[0005] The utility model aims to solve the above-mentioned deficiencies in the prior art and provide a fluidized bed with a built-in cyclone separator capable of controlling the reduction degree of fine iron ore particles.
[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0007] A fluidized bed for reducing iron ore powder, comprising a fluidized bed body, an air inlet, a bottom air chamber, an air distribution plate, a fluidizing chamber, a feed port, and a discharge port; characterized in that: it comprises at least one built-in cyclone separator; the built-in cyclone separator is arranged in the upper part of the fluidized bed body, the gas inlet of the built-in cyclone separator is arranged in the fluidizing chamber, and the gas outlet of the built-in cyclone separator passes through the fluidized bed body and is connected to an external subsequent flue gas channel; the built-in cyclone separator is equipped with at least one discharge pipe, the discharge pipe of the built-in cyclone separator passes through the fluidized bed body and is connected to an external material conveying system, and the discharge pipe is independent or has a fork before exiting the fluidized bed body.
[0008] If the discharge pipe is bifurcated, the discharge pipe has one or more bifurcations, at least one of which forms an inner discharge pipe. The utility model integrates a cyclone separator into a fluidized bed reactor, combines the fluidized bed and the cyclone separator into one, occupies a smaller overall space, has a smaller system heat loss, and solves the above-mentioned cyclone separator's larger overall weight and higher cost problems. At the same time, by setting the outlet of the cyclone separator discharge pipe, fine particle materials that have reached a preset reduction degree are discharged out of the bed in a timely manner, thereby improving the efficiency of the fluidized bed reactor.
[0009] Furthermore, a valve is provided on the channel where the discharge pipe of the built-in cyclone separator extends out of the fluidized bed body, and the proportion of fine particles discharged from the fluidized bed through the built-in cyclone separator can be effectively adjusted through the valve. Through this adjustment, the average reduction time of fine particles in the fluidized bed can be controlled, thereby greatly improving the production efficiency of the fluidized bed while ensuring the reduction degree.
[0010] Furthermore, the built-in cyclone separator is fixed inside the fluidized bed via a hanger and / or a bracket; it can be fixed on the side wall of the fluidized bed or on the top of the fluidized bed.
[0011] Preferably, no matter how many cyclone separators are arranged in the fluidized bed, at least one of the cyclone separators has an independent discharge pipe or a fork in a forked discharge pipe extending out of the fluidized bed, and a regulating valve is provided on it, so as to control the discharge ratio of fine particles and realize the control of the average reaction time of fine particles in the fluidized bed. The outlets of the remaining discharge pipes are all arranged inside the fluidized bed, and air lock valves or sealing elbows are provided on them. The cyclone separator serves to separate solid particles from gas, which not only avoids the loss of fine particles as the gas is discharged and causes pollution, but also, by setting the outlet of the cyclone separator discharge pipe, the fine particles that have reached the preset reduction degree are discharged out of the furnace in time, thereby improving the efficiency of the fluidized bed reactor.
[0012] The utility model provides a method for reducing iron ore powder, using the above-mentioned fluidized bed, the iron ore powder is added from the feed port of the fluidized bed, and a solid material bed layer is formed above the air distribution plate, and fluidization is formed under the action of the reducing gas;
[0013] The reducing gas enters the bottom wind chamber from the air inlet and is evenly distributed through the air distribution plate. After passing through the fluidized bed, the reducing gas carries the fine iron ore particles into the built-in cyclone separator. The separated gas is discharged from the gas outlet of the built-in cyclone separator and enters the external subsequent flue gas channel.
[0014] Fine particles of iron ore powder enter from the air inlet of the built-in cyclone separator along with the reducing gas, and most of them are separated by the built-in cyclone separator and then enter the discharge pipe to be discharged out of the fluidized bed, or enter the inner discharge pipe to return to the fluidized bed layer and be discharged out of the fluidized bed through the fluidized bed discharge port together with large particles in the bed layer.
[0015] Preferably, the average time for the fine particles separated by the built-in cyclone separator to be reduced in the fluidized bed is controlled by adjusting the valve on the portion of the discharge pipe extending out of the fluidized bed.
[0016] The beneficial effects of the utility model are:
[0017] By setting the outlet of the discharge pipe of the built-in cyclone separator, the fine particle materials reaching the preset reduction degree are discharged out of the bed in time, thereby improving the efficiency of the fluidized bed reactor. The efficiency of the fluidized bed reactor is increased by about 15-30%.
[0018] By setting up other auxiliary components, the equipment design becomes more compact and stronger, thus increasing the service life of the equipment.
[0019] The utility model integrates the fluidized bed and the cyclone separator into one by embedding the cyclone separator into the fluidized bed reactor, so that the overall space occupied is small, and the floor space is saved by about 40-60%. At the same time, since no insulation is required, the heat dissipation of the cyclone separator is directly supplied to the fluidized bed, the system heat loss is small, energy is saved, and about 10-20% energy is saved. At the same time, the above-mentioned cyclone separator is solved. The problem of large weight and high cost is solved. The cyclone separator does not need to be provided with an insulation layer, which reduces the weight by about 10-20% and saves 15-25% of the cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a schematic diagram of the fluidized bed structure for reducing iron ore powder according to Example 1 of the utility model;
[0021] Figure 2 This is a schematic diagram of the fluidized bed structure for reducing iron ore powder described in Example 3 of the present utility model.
[0022] The following are the descriptions of the reference numerals:
[0023] 1. Fluidized bed body; 2. Cyclone separator; 3. Discharge pipe; 4. Air distribution plate; 5. Bottom air chamber; 6. Discharge port; 7. Feed port; 8. Air inlet. DETAILED DESCRIPTION
[0024] The following is a detailed description of the embodiments of the present invention with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. The present invention can be embodied in a variety of different forms and is not limited to the embodiments described herein.
[0025] In order to clearly explain the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.
[0026] Throughout the specification, when it is mentioned that a part “includes” a certain constituent element, unless there is any special description to the contrary, it does not exclude other constituent elements but means that other constituent elements may be included.
[0027] Example 1
[0028] Refer to the following Figure 1 , illustrating a fluidized bed for reducing iron ore powder according to a first embodiment. The fluidized bed for reducing iron ore powder according to the first embodiment comprises a fluidized bed body 1, a cyclone separator 2, a discharge pipe 3, an air distribution plate 4, a bottom air chamber 5, a discharge port 6, a feed port 7, and an air inlet 8.
[0029] The cyclone separator 2 is arranged in the fluidized bed body 1 and is located at the upper part of the fluidized bed body space. The cyclone separator includes an air inlet, a smoke outlet, and a discharge port. The smoke outlet of the cyclone separator passes through the fluidized bed body and extends out of the bed, and is connected to the subsequent smoke channel; the discharge port of the cyclone separator is connected to the discharge pipe 3, such as Figure 1 As shown, the discharge pipe is provided with two outlets, one of which is provided inside the fluidized bed, and the other is provided outside the fluidized bed and connected to the subsequent material conveying system. The discharge pipe provided outside the fluidized bed is provided with a valve at its outlet; the proportion of the material discharged through the cyclone separator can be effectively adjusted by the valve. By adjusting the opening degree of the valve, the amount of fine particle material discharged through the cyclone separator is adjusted, thereby controlling the average reduction time of the fine particle material in the fluidized bed.
[0030] The cyclone separator is fixed on the top of the fluidized bed through a hanger and / or a bracket; the discharge pipe is fixed inside the fluidized bed through a bracket.
[0031] Iron ore powder is added from the feed port. Under the action of the reducing airflow, the iron ore powder is fluidized inside the fluidized bed and forms a fluidized bed layer. The gas and solid are fully in contact to achieve a reduction reaction, and finally discharged from the bed through the discharge port 6. Fine particles enter from the air inlet of the cyclone separator 2 with the reducing gas. The cyclone separator 2 is arranged inside to play a dust removal function on the one hand. On the other hand, the fluidized bed is usually operated at high temperature, and the equipment needs to be kept warm. It is arranged inside the fluidized bed. The heat dissipation of the cyclone separator belongs to the internal heat of the system. The cyclone separator does not need to be additionally insulated, and the heat dissipation loss of the cyclone separator is avoided. The cyclone separator is arranged inside the fluidized bed, which makes full use of the space above the fluidized bed and can effectively reduce the floor space of the equipment.
[0032] Most of the fine particles of iron ore powder that enter the air inlet of the cyclone separator 2 with the reducing gas are retained by the cyclone separator and enter the discharge pipe. Due to the action of gravity, they flow downward, and part of them enter the bottom fluidized bed layer through the discharge pipe outlet arranged inside the fluidized bed, and the other part is discharged from the bed through the outlet arranged outside the fluidized bed. According to the actual production conditions, the amount of material discharged is controlled by the valve, so that the average residence time of the fine particles of iron ore powder in the fluidized bed is controlled to achieve the preset reduction degree.
[0033] The reducing gas enters the bottom air chamber 5 from the air inlet 8, and is evenly distributed through the air distribution plate 4. After passing through the fluidized bed, the reducing gas carries the fine particles of iron ore powder into the cyclone separator, and after separating most of the fine particles, it is discharged from the gas outlet of the cyclone separator and enters the subsequent flue gas duct. The reducing gas in this embodiment is hydrogen and / or carbon monoxide.
[0034] When the fluidized bed is working, fine particles are inevitably carried away by the gas and leave the fluidized bed layer. The role of the cyclone separator is to purify the gas on the one hand and to recover the fine particles on the other hand. If the discharge pipe outlet of the cyclone separator arranged inside the fluidized bed is arranged inside the fluidized bed, the probability of fine particles being discharged from the fluidized bed is low. However, the reaction kinetic conditions of fine particles are better, and the time to reach product conditions is faster. They cannot be discharged from the fluidized bed in time, which greatly reduces the production efficiency of the fluidized bed. The utility model arranges one outlet of the discharge pipe of the cyclone separator outside the fluidized bed, so that the fine particles can be discharged from the bed in time after reaching the preset average reduction degree, thereby greatly improving the production efficiency of the fluidized bed.
[0035] Example 2
[0036] The other parts are the same as those in Example 1, except that the discharge pipe is provided with an outlet, which is provided outside the fluidized bed and connected to the subsequent material conveying system. A valve is provided on the outlet; the amount of material discharged from the cyclone separator can be effectively adjusted by the valve.
[0037] The discharge pipe has only one outlet, and the materials collected by the cyclone separator are discharged outside the fluidized bed. Since fine particles have better fluidization and faster reaction speed, this setting allows fine particles to leave the fluidized bed quickly, greatly improving the reaction efficiency of the fluidized bed. Compared with the outlet set inside the fluidized bed, the reaction efficiency of the fluidized bed is improved by 15-30%.
[0038] Example 3
[0039] Refer to the following Figure 2 , illustrating the fluidized bed for reducing iron ore powder of this embodiment.
[0040] The fluidized bed with built-in cyclone separator for reducing iron ore powder in this embodiment comprises a fluidized bed body 1, a cyclone separator 2, a discharge pipe 3, an air distribution plate 4, a bottom air chamber 5, a discharge port 6, a feed port 7, and an air inlet 8. Different from the above-mentioned embodiment 1, the fluidized bed with built-in cyclone separator for reducing iron ore powder in this embodiment is provided with two cyclones inside; the discharge pipe outlet of one cyclone separator is arranged inside the fluidized bed, and the fine iron ore particles collected by the cyclone separator are discharged into the fluidized bed layer from the discharge pipe outlet; the discharge pipe outlet of the other cyclone separator is arranged outside the fluidized bed, and the fine iron ore particles collected by the cyclone separator are discharged from the fluidized bed from the discharge pipe outlet.
[0041] The multiple cyclone separators are set up to achieve better gas purification effect and collect more fine particles. The reaction efficiency of the fluidized bed is increased by 15-25%.
[0042] Iron ore powder is added from the feed port 7. Under the action of the reducing airflow, the iron ore powder is fluidized inside the fluidized bed and forms a fluidized bed layer. The gas and solid are fully contacted to perform a reduction reaction, and finally discharged from the bed through the discharge port 6. Fine particles enter the cyclone separator 2 from the air inlet of the cyclone separator along with the reducing gas. Most of the fine particles of the iron ore powder are left by the cyclone separator 2 and enter the discharge pipe 3, and move downward due to the action of gravity. Two cyclones 2 are arranged inside the fluidized bed, and the outlet of the discharge pipe 3 of one cyclone separator 2 is arranged inside the fluidized bed, and the fine particles of iron ore powder collected by the cyclone separator 2 are discharged into the fluidized bed layer from the outlet of the discharge pipe 3; the outlet of the discharge pipe 3 of the other cyclone separator 2 is arranged outside the fluidized bed, and the fine particles of iron ore powder collected by the cyclone separator 2 are discharged from the fluidized bed from the outlet of the discharge pipe 3.
[0043] The reducing gas (such as hydrogen and / or carbon monoxide) enters the bottom wind chamber 5 from the air inlet 8, and is evenly distributed through the air distribution plate 4. After passing through the fluidized bed layer, the reducing gas carries the fine iron ore particles into the cyclone separator 2 for dust removal, and is finally discharged from the gas outlet of the cyclone separator 2 and enters the subsequent flue gas duct.
[0044] Example 4
[0045] The other parts are the same as those in Example 3, except that two cyclone separators are provided inside the fluidized bed with a built-in cyclone separator for reducing iron ore powder; and the discharge pipes of the two cyclone separators are provided with two outlets. One of the outlets of the discharge pipe of each cyclone separator is provided inside the fluidized bed, and the other is provided outside the fluidized bed and connected to the subsequent feeding system.
[0046] A valve is provided at the outlet outside the fluidized bed; the amount of material discharged from the cyclone separator can be effectively adjusted by the valve. Alternatively, a valve may be provided at the outlet outside the fluidized bed of only one of the cyclone separators' discharge pipes. The valve is adjusted to control the residence time of the iron ore fine particles in the fluidized bed.
[0047] Example 5
[0048] The other parts are the same as those in Example 3, except that two cyclones are provided inside the fluidized bed with built-in cyclone separator for reducing iron ore powder; the discharge pipe of one of the cyclones is provided with an outlet, which is provided outside the fluidized bed and connected to the subsequent feeding system. The discharge pipe of the other cyclone is provided with two outlets, one of which is provided inside the fluidized bed and the other is provided outside the fluidized bed and connected to the subsequent feeding system.
[0049] In this embodiment, the outlet is arranged so that the fine particles are discharged from the fluidized bed in time, thereby controlling the residence time of the fine particles in the fluidized bed.
[0050] Those skilled in the art should realize that the above embodiments are only used to illustrate the present invention, but not to limit the present invention.
Claims
1. A fluidized bed for reducing iron ore powder, comprising a fluidized bed body, an air inlet, a bottom air chamber, an air distribution plate, a fluidizing chamber, a feed inlet, and a discharge port; characterized in that: At least one built-in cyclone separator is included; the built-in cyclone separator is arranged in the upper part of the fluidized bed body, the gas inlet of the built-in cyclone separator is arranged in the fluidizing chamber, and the gas outlet of the built-in cyclone separator passes through the fluidized bed body and is connected to the external subsequent flue gas channel; The built-in cyclone separator is equipped with at least one discharge pipe, and the discharge pipe of the built-in cyclone separator passes through the fluidized bed body and is connected to the external material delivery system. The discharge pipe is independent or bifurcated.
2. The fluidized bed for reducing iron ore powder according to claim 1, characterized in that: The discharge pipe is bifurcated, and the discharge pipe is bifurcated before extending out of the fluidized bed body; there are one or more bifurcations, at least one of which forms an inner discharge pipe.
3. A fluidized bed for reducing iron ore powder according to claim 1, characterized in that: A valve is arranged on the channel where the discharge pipe of the built-in cyclone separator extends out of the fluidized bed body.
4. The fluidized bed for reducing iron ore powder according to any one of claims 1 to 3, characterized in that: The built-in cyclone separator is fixed inside the fluidized bed via a hanger and / or a bracket.
5. The fluidized bed for reducing iron ore powder according to claim 4, characterized in that: The number of the cyclone separators is one or more.
6. The fluidized bed for reducing iron ore powder according to claim 1, characterized in that: The discharge pipe is fixed inside the fluidized bed through a bracket.