Coal gangue low-temperature heat treatment device

Abstract

The utility model relates to comprehensive utilization of solid wastes, in particular to a low-temperature heat treatment device for coal gangue. Comprising a stock bin (1), a first-stage cyclone preheater (3), a second-stage cyclone preheater (4) and a boiling combustion system (6), an outlet of the stock bin (1) is communicated with an inlet of the first-stage cyclone preheater (3) and an inlet of the second-stage cyclone preheater (4) at the same time, and an outlet of the first-stage cyclone preheater (3) is communicated with an inlet of the second-stage cyclone preheater (4). And an outlet of the secondary cyclone preheater (4) is communicated with the boiling combustion system (6). The cyclone powder collector (7), the secondary cyclone preheater (4) and the boiling combustion system (6) are communicated with one another through the tee joint (9), heat circulation is achieved, and the heat utilization rate is increased; a first combustor (12) and a second combustor (13) are sequentially arranged on the side wall of the lower portion of the boiling calcining furnace, heat needed for maintaining the stable temperature can be supplemented, and the purpose of accurate temperature control is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of comprehensive utilization of solid waste, especially in the IPC F27B17 field. More specifically, it relates to a low-temperature heat treatment device for coal gangue. Background Art

[0002] Coal gangue is an associated product in the process of coal mining, with a large annual discharge. Coal gangue contains a large amount of beneficial elements such as silicon and aluminum, which are the basic elements of inorganic non-metallic materials. Especially in some areas, the coal gangue has a high aluminum content, low impurity content, and is rich in a large amount of kaolinite components, having high development and utilization value. Generally, the heat treatment process of coal gangue includes the following aspects: using lump coal gangue as raw material and adopting vertical kiln and tunnel kiln calcination processes; using powdered coal gangue as raw material and adopting rotary kiln and suspension furnace calcination; after grinding and preparing the green body of coal gangue, using tunnel kiln and shuttle kiln for calcination treatment, etc. The above heat treatment processes all have some problems. For example, the vertical kiln calcination process of lump coal gangue has problems such as long calcination cycle, raw materials being prone to incomplete calcination, and the need for secondary sorting. The tunnel kiln calcination of lump coal gangue also has problems such as raw materials being prone to incomplete calcination and the need for secondary sorting, and high energy consumption. The rotary kiln calcination process using powdered coal gangue has disadvantages such as small contact area between raw materials and hot gas, difficult temperature control, and unstable quality. The calcination process using a tunnel kiln or shuttle kiln for the formed green body has problems such as complex process, the green body being difficult to burn through, easy to turn black, and the calcined green body needing to be subjected to secondary crushing and grinding treatment, with high energy consumption.

[0003] CN1600687A describes an ultra-fine kaolin suspension heat treatment process. Although the heat utilization efficiency is relatively high, there are also problems such as long residence time of materials, and it is difficult to control the stability of material quality due to the mixing of the "over-burning" phenomenon of some materials cycling repeatedly and the "under-burning" phenomenon of short residence time during the cyclic calcination process; patents such as CN100431957C describe a fluidized instant calcination process for coal-series kaolin. Although it has characteristics such as high heat utilization efficiency and short treatment time, it is only used as a pre-treatment process for other heat treatment systems, with problems such as large equipment investment and complex process. Summary of the Utility Model

[0004] The utility model provides a low-temperature heat treatment device for coal gangue, including: a feed bin, a primary cyclone preheater, a secondary cyclone preheater, and a fluidized combustion system. The outlet of the feed bin is simultaneously connected to the primary cyclone preheater and the secondary cyclone preheater. The outlet of the primary cyclone preheater is connected to the inlet of the secondary cyclone preheater. The outlet of the secondary cyclone preheater is connected to the fluidized combustion system.

[0005] The device further includes a feeder. The outlet of the secondary cyclone preheater is connected to the fluidized combustion system through the feeder.

[0006] The device further includes a dust collector and a chimney, and the primary cyclone preheater is connected to the chimney through the dust collector.

[0007] The device further includes a metering feeding device, and the outlet of the silo is connected to the inlets of both the primary cyclone preheater and the secondary cyclone preheater through the metering feeding device.

[0008] The device further includes a cyclone powder collector and a three-way pipe. The cyclone powder collector is connected to the fluidized bed combustion system, and the three-way pipe connects the following structures to each other: the cyclone powder collector, the secondary cyclone preheater, and the fluidized bed combustion system.

[0009] The cyclone powder collector is connected to the secondary cyclone preheater through the primary cyclone preheater.

[0010] The fluidized bed combustion system includes a blower, a hot air device, a first burner, a second burner, and an overflow port.

[0011] The hot air device is arranged at the bottom of the fluidized bed combustion system, and the overflow port is arranged at the side of the fluidized bed combustion system.

[0012] The first burner and the second burner are arranged on the side of the fluidized bed combustion system in sequence from bottom to top. The blower is connected to the bottom of the fluidized bed combustion system through a three-way pipe.

[0013] The device further includes a finished product discharge port, which is arranged at the bottom of the cyclone powder collector.

[0014] The working principle of the device is as follows: After the coal gangue raw material is crushed and ground, it enters the primary cyclone preheater from the silo through the metering feeding device for preheating and drying, and then enters the secondary cyclone preheater for high-temperature preheating and dehydration. After preheating and dehydration, the material enters the fluidized bed combustion system through a feeder for dehydration, decarbonization, and impurity removal. After being calcined in the fluidized bed combustion system, some of the finer particles of the material enter the cyclone powder collector from the upper part of the fluidized bed combustion system along with the high-temperature flue gas, and are discharged from the finished product discharge port at its lower part. The discharged material is cooled and collected to obtain the finished product. The coarser part of the particles obtained by calcination flows out through the overflow port on the lower side wall of the fluidized bed combustion system, and the discharged material is cooled and collected to obtain the finished product. The high-temperature flue gas during the calcination process enters the secondary cyclone preheater and the primary cyclone preheater in sequence through a part of the three-way pipe from the upper part of the cyclone powder collector, serving as the heat source for the two-stage cyclone preheater. The discharged flue gas enters the chimney and is exhausted after dust removal by the dust collector; another part serves as the heat source of the heat exchanger to heat the combustion-supporting air. The combustion-supporting air preheated by the hot air device enters the fluidized bed combustion system after being heated by the burner and cooperates with the blower to provide the main heat source and hot air flow. At the same time, in order to maintain the stability of the temperature inside the fluidized bed furnace, the first burner and the second burner are arranged in sequence at the lower side wall position of the fluidized bed calcination furnace to supplement the heat required to maintain a stable temperature.

[0015] Beneficial effects

[0016] 1. This application connects the following structures to each other through a three-way connection: a cyclone powder collector, a secondary cyclone preheater, and a fluidized bed combustion system, achieving a heat cycle and improving the heat utilization rate.

[0017] 2. This application sequentially arranges a first burner and a second burner at the lower side wall position of the fluidized bed calciner, which can supplement the heat required to maintain a stable temperature and achieve the purpose of precise temperature control.

[0018] 3. This application is provided with two-stage preheating devices, a primary cyclone preheater and a secondary cyclone preheater, which can not only preheat the material stably, but also the high-temperature flue gas can provide a stable heat source for the preheater.

[0019] 4. This application is provided with an overflow port and a finished product discharge port, and the two-stage discharge ports improve the collection rate of the finished product particles.

[0020] 5. This application is provided with a blower and a hot air device, and the hot air flow can make the powder particles be calcined fully and evenly, improving the quality stability of the calcined product. Description of the Drawings

[0021] Figure 1 It is a low-temperature heat treatment device for coal gangue in Example 1.

[0022] Wherein: 1. Hopper, 2. Metering feeding device, 3. Primary cyclone preheater, 4. Secondary cyclone preheater, 5. Feeder, 6. Fluidized bed combustion system, 7. Cyclone powder collector, 8. Finished product discharge port, 9. Three-way connection, 10. Blower, 11. Hot air device, 12. First burner, 13. Second burner, 14. Overflow port, 15. Dust collector, 16. Chimney. Detailed Embodiment

[0023] Example 1

[0024] A low-temperature heat treatment device for coal gangue, as Figure 1 shown, includes: a hopper 1, a primary cyclone preheater 3, a secondary cyclone preheater 4, and a fluidized bed combustion system 6. The outlet of the hopper 1 is simultaneously connected to the primary cyclone preheater 3 and the secondary cyclone preheater 4. The outlet of the primary cyclone preheater 3 is connected to the inlet of the secondary cyclone preheater 4. The outlet of the secondary cyclone preheater 4 is connected to the fluidized bed combustion system 6.

[0025] The device also includes a feeder 5, a dust collector 15, a chimney 16, a metering feeding device 2, a cyclone powder collector 7 and a tee 9; the outlet of the secondary cyclone preheater 4 is connected to the boiling combustion system 6 through the feeder 5; the primary cyclone preheater 3 is connected to the chimney 16 via the dust collector 15; the outlet of the silo 1 is connected to the inlets of the primary cyclone preheater 3 and the secondary cyclone preheater 4 via the metering feeding device 2; the cyclone powder collector 7 is connected to the boiling combustion system 6, and the tee 9 connects the following structures to each other: the cyclone powder collector 7, the secondary cyclone preheater 4 and the boiling combustion system 6; the cyclone powder collector 7 is connected to the secondary cyclone preheater 4 via the primary cyclone preheater 3.

[0026] The boiling combustion system 6 includes a blower 10, a hot air device 11, a first burner 12, a second burner 13, and an overflow port 14; the hot air device 11 is arranged at the bottom of the boiling combustion system 6, and the overflow port 14 is arranged at the side of the boiling combustion system 6; the first burner 12 and the second burner 13 are arranged on the side of the boiling combustion system 6 from bottom to top, and the blower 10 is connected to the bottom of the boiling combustion system 6 through a tee 9.

[0027] The device further comprises a finished product discharge port 8 , and the finished product discharge port 8 is arranged at the bottom of the cyclone powder collector 7 .

[0028] The working principle of the device is as follows: after the gangue raw material is crushed and ground, it enters the first-stage cyclone preheater 3 through the metering feeding device 2 from the silo 1 for preheating and drying, and then enters the second-stage cyclone preheater 4 for high-temperature preheating and dehydration. After preheating and dehydration, the material enters the boiling combustion system 6 through the feeder 5 for dehydration, decarbonization and impurity removal. After the material is calcined in the boiling combustion system 6, part of the material with finer particles is entered into the cyclone powder collector 7 from the upper part of the boiling combustion system 6 along with the high-temperature flue gas, and is discharged from the finished product discharge port 8 at the lower part thereof. The discharged material is cooled and collected to be the finished product. The coarser part of the calcined particles flows out through the overflow port 14 on the lower side wall of the boiling combustion system 6, and the outflowing material is cooled and collected to be the finished product. The high-temperature flue gas during the calcination process enters the secondary cyclone preheater 4 and the primary cyclone preheater 3 in sequence from the upper part of the cyclone powder collector 7 through a part of the tee 9, and serves as the heat source of the two-stage cyclone preheater. The exhaust flue gas is dedusted by the dust collector 15 and then discharged into the chimney 16; the other part is used as the heat source of the heat exchanger to heat the combustion air. The combustion air preheated by the hot air device 11 enters the boiling combustion system 6 after being heated by the burner and cooperates with the blower 10 to provide the main heat source and hot air flow. At the same time, in order to maintain the stability of the internal temperature of the boiling furnace, the first burner 12 and the second burner 13 are sequentially arranged on the lower side wall of the boiling calcining furnace to supplement the heat required to maintain a stable temperature.

Claims

1. A low temperature heat treatment device for coal gangue, characterized in that: include: A material bin (1), a primary cyclone preheater (3), a secondary cyclone preheater (4) and a boiling combustion system (6), wherein the outlet of the material bin (1) is communicated with both the primary cyclone preheater (3) and the secondary cyclone preheater (4), the outlet of the primary cyclone preheater (3) is communicated with the inlet of the secondary cyclone preheater (4), and the outlet of the secondary cyclone preheater (4) is communicated with the boiling combustion system (6).

2. The low temperature heat treatment device for coal gangue according to claim 1, characterized in that: It also includes a feeder (5), and the outlet of the secondary cyclone preheater (4) is connected to the boiling combustion system (6) through the feeder (5).

3. The low temperature heat treatment device for coal gangue according to claim 2, characterized in that: It also includes a dust collector (15) and a chimney (16), and the primary cyclone preheater (3) is connected to the chimney (16) via the dust collector (15).

4. The low-temperature heat treatment device for coal gangue according to claim 3, characterized in that: It also comprises a metering feeding device (2), and the outlet of the silo (1) is connected to the inlet of the primary cyclone preheater (3) and the inlet of the secondary cyclone preheater (4) via the metering feeding device (2).

5. The low-temperature heat treatment device for coal gangue according to claim 4, characterized in that: It also includes a cyclone powder collector (7) and a tee (9), wherein the cyclone powder collector (7) is connected to the boiling combustion system (6), and the tee (9) connects the following structures to each other: the cyclone powder collector (7), the secondary cyclone preheater (4) and the boiling combustion system (6).

6. The low-temperature heat treatment device for coal gangue according to claim 5, characterized in that: The cyclone powder collector (7) is connected to the secondary cyclone preheater (4) via the primary cyclone preheater (3).

7. The low-temperature heat treatment device for coal gangue according to claim 6, characterized in that: The boiling combustion system (6) comprises a blower (10), a hot air device (11), a first burner (12), a second burner (13), and an overflow port (14).

8. The low-temperature heat treatment device for coal gangue according to claim 7, characterized in that: The hot air device (11) is arranged at the bottom of the boiling combustion system (6), and the overflow port (14) is arranged at the side of the boiling combustion system (6).

9. The low-temperature heat treatment device for coal gangue according to claim 8, characterized in that: The first burner (12) and the second burner (13) are arranged on the side of the boiling combustion system (6) from bottom to top, and the blower (10) is connected to the bottom of the boiling combustion system (6) through a tee (9).

10. The low-temperature heat treatment device for coal gangue according to claim 9, characterized in that: It also comprises a finished product discharge port (8), wherein the finished product discharge port (8) is arranged at the bottom of the cyclone powder collector (7).

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