CN113028827A

CN113028827A - Operation method of spodumene calcination conversion device

Info

Publication number: CN113028827A
Application number: CN202110474848.8A
Authority: CN
Inventors: 李嘉隆; 赵迎朝; 潘玉峰; 陈辉; 李利平; 马晓强; 赵雪; 杜静芳; 董雷亭; 陈世超
Original assignee: Luoyang Shente Engineering Technology Co ltd
Current assignee: Luoyang Shente Engineering Technology Co ltd
Priority date: 2021-04-29
Filing date: 2021-04-29
Publication date: 2021-06-25

Abstract

An operation method of a spodumene calcination conversion device comprises the steps that a kiln tail smoke chamber is arranged at the kiln tail of a rotary kiln, the rotary kiln and the kiln tail smoke chamber form a kiln body, a feeding and air exhausting mechanism is arranged above the kiln body, a pipeline is arranged between the feeding and air exhausting mechanism and the kiln body, an ascending flue is arranged on the kiln tail smoke chamber, a tertiary air pipe is arranged between the ascending flue and the kiln head of the rotary kiln, an ascending flue burner is arranged on the ascending flue, a kiln head burner is arranged on the kiln head, a primary air fan is arranged on one side of the kiln head burner, a single-cylinder cooler is arranged on one side of the front end of the rotary kiln, a roller crusher is arranged below a discharge port of the single-cylinder cooler, a zipper machine is arranged below a discharge port of the roller crusher, and a bucket elevator is; the invention integrates material drying and preheating, improves heat exchange efficiency, reduces equipment investment and improves yield.

Description

Operation method of spodumene calcination conversion device

Technical Field

The invention relates to the field of kilns, in particular to an operation method of a spodumene calcining and converting device.

Background

Lithium is widely used in the industries of ceramics, glass, lubricants, refrigerating fluids, nuclear industry, photoelectricity and the like. With the development of new energy, the battery industry has become the largest consumer field of lithium, and the applications of lithium batteries mainly include: traffic power supply, electric power energy storage power supply, mobile communication power supply and the like.

Spodumene is currently the major industrial feedstock for lithium chemicals. Spodumene has three crystal forms: alpha-type spodumene, beta-type spodumene and gamma-type spodumene, wherein the alpha-type spodumene is in spodumene ores, the alpha-type spodumene is converted into the beta-type spodumene by calcining at 1100-1200 ℃, and the alpha-type spodumene is converted into the gamma-type spodumene at the temperature of over 1200 ℃. Among them, alpha-spodumene is a monoclinic system with compact structure, and the chemical inertness is large except hydrofluoric acid and hardly reacts with various acids and alkalis, so that it is not suitable for directly extracting lithium. The beta-spodumene is in a tetragonal crystal form, has the thermal cracking property, can react with acid and alkali, and is suitable for extracting lithium.

At present, the spodumene calcination conversion is mostly carried out by adopting a single rotary kiln or a rotary kiln with a suspension preheater outside the kiln. The rotary kiln with the kiln outer suspension preheater only uses the waste heat of the kiln tail flue gas to carry out heat exchange on the materials in the preheater, the temperature of the materials entering the kiln is 270-300 ℃, the temperature required by spodumene crystal form conversion is 1100-1200 ℃, and most of the heat exchange is carried out in the rotary kiln. The required roasting time for spodumene crystal form conversion is long, so that the rotary kiln adopted by the existing spodumene calcination is large in specification and low in rotating speed, the rotating speed is usually 1r/min, heat convection and heat radiation are adopted as heat exchange modes in the rotary kiln, the low kiln speed causes the rolling times of materials in the rotary kiln to be few, the lifting height is low, the heat exchange efficiency is low, and the yield is low.

The spodumene is usually selected by flotation, the water content of the spodumene raw material is usually 15-18%, and the fineness is below 0.5 mm. The existing production line utilizes the waste heat of the smoke at the tail of the kiln head to dry, a rotary dryer needs to be arranged independently, a heat-drawing air pipeline from the tail of the kiln head is long, the temperature drop is large, and meanwhile, the rotary dryer needs to be provided with vehicle-collecting equipment. The temperature of the kiln head and the kiln tail flue gas is usually only 120-150 ℃, the drying effect is poor due to the excessively low temperature, the moisture content of the dried raw material is more than 8%, the raw material has high moisture content and needs to absorb a large amount of heat for dehydration after entering the rotary kiln, the retention time of the raw material in the rotary kiln is further increased, and the yield is influenced; how to reduce the energy consumption of spodumene calcination and improve the heat exchange efficiency and yield when the alpha-type spodumene is calcined and converted into the beta-type spodumene becomes a long-standing technical problem which is difficult to solve.

In view of the above, a method of operating a spodumene calcination conversion apparatus has been developed.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide an operation method of a spodumene calcining and converting device, which integrates material drying and preheating, improves the heat exchange efficiency, reduces the equipment investment and improves the yield.

In order to achieve the purpose, the invention adopts the following technical scheme: a method of operating a spodumene calcination conversion apparatus, said spodumene calcination conversion apparatus comprised of: the rotary kiln comprises a rotary kiln, a kiln tail smoke chamber, a kiln head burner, a primary fan, a single-cylinder cooler, a roller crusher, a zipper machine, a bucket elevator, an ascending flue burner, a tertiary air pipe, a C3 suspension preheater, a C1 suspension preheater, a C2 suspension preheater, a Venturi dryer, a rotary feeder and a hot blast stove; the kiln tail of the rotary kiln is provided with a kiln tail smoke chamber, the rotary kiln and the kiln tail smoke chamber form a kiln body, a feeding and exhausting mechanism is arranged above the kiln body, a pipeline is arranged between the feeding and exhausting mechanism and the kiln body, an ascending flue is arranged on the kiln tail smoke chamber, a tertiary air pipe is arranged between the lower end of the ascending flue and an air outlet of a kiln head cover of the rotary kiln, an ascending flue burner is arranged on the ascending flue above the tertiary air pipe, a kiln head burner is arranged on a kiln head of the rotary kiln, a primary fan is arranged on one side of the kiln head burner, an air supply pipeline is arranged between an air outlet of the primary fan and an air inlet of the kiln head burner, a single-cylinder cooler is arranged on one side of the front end of the rotary kiln, a pipeline is arranged between an air outlet of the single-cylinder cooler and the kiln head cover of the rotary kiln, a roller type crusher is arranged below a discharge outlet of the single-cylinder cooler;

the structure of the feeding and air exhausting mechanism is as follows: a C3 suspension preheater is arranged on one side of the upper part of an uptake flue, a hot gas material mixing pipeline is arranged between an air outlet at the upper end of the uptake flue and an air inlet at the upper end of the C3 suspension preheater, a feeding pipeline is arranged between a material outlet at the lower end of the C3 suspension preheater and a material inlet of a kiln tail smoke chamber, a C2 suspension preheater is arranged on one side above the C3 suspension preheater, a hot gas material mixing pipeline is arranged between an air outlet at the upper end of the C3 suspension preheater and an air inlet of the C2 suspension preheater, a feeding pipeline is arranged between a material outlet at the lower end of the C2 suspension preheater and a material inlet at the lower part of the uptake flue, a C1 suspension preheater is arranged on one side above the C2 suspension preheater, a material mixing pipeline is arranged between a material outlet at the lower end of the C1 suspension preheater and a C3 suspension preheater, a feeding pipeline is arranged between a hot gas material mixing pipeline of the C2, an air supply pipeline is arranged between an air outlet at the upper end of the C2 suspension preheater and the lower end of the venturi dryer, one side of the lower end of the venturi dryer is provided with a hot blast stove, an air supply pipeline is arranged between an air outlet of the hot blast stove and an air inlet at the lower end of the venturi dryer, one side of the venturi dryer is provided with a rotary feeder, and a feeding pipeline is arranged between a discharge outlet of the rotary feeder and a feed inlet of the venturi dryer.

An air supply pipeline is arranged between an air outlet of the C1 suspension preheater and a waste gas treatment system, during production, pulverized coal or natural gas is used as a fuel for a kiln head burner, a rising flue burner and a hot blast stove, and spodumene powder with the granularity of less than 05mm is used as a raw material; spodumene powder enters a Venturi dryer through a rotary feeder, hot air in a pipeline is used for drying materials, when the air temperature in an air supply pipeline at the initial feeding stage is too low, hot air generated by a hot air furnace is used for drying auxiliary raw materials, the spodumene powder enters a C1 suspension preheater through a hot air and material mixing pipeline at the upper part of the Venturi dryer, preheating and gas-solid separation are carried out in a C1 suspension preheater, spodumene solid particles after gas-solid separation downwards move through the feeding pipeline to enter a hot air and material mixing pipeline between the C3 suspension preheater and the C2 suspension preheater and then are sent into the C2 suspension preheater, preheating and gas-solid separation are carried out in a C2 suspension preheater, spodumene solid particles after gas-solid separation downwards move through the feeding pipeline to enter an ascending flue for preheating, spodumene solid particles in the ascending flue enter a C3 suspension preheater through the hot air and material mixing pipeline, preheating and gas-solid separation are carried out in a C3 suspension preheater, spodumene solid particles after gas-solid separation move downwards and enter a kiln tail smoke chamber through a feeding pipeline to enter a rotary kiln for calcination, the spodumene solid particles enter a single-cylinder cooler through a pipeline of a kiln head cover of the rotary kiln to be cooled, high-temperature air for cooling the clinker enters the rotary kiln and a tertiary air pipe through pipelines to respectively provide oxygen required for combustion in the rotary kiln and a rising flue, the clinker cooled by the single-cylinder cooler enters a roller crusher to be crushed, the crushed clinker enters a bucket elevator through a zipper elevator, and the crushed clinker enters a clinker silo through the bucket elevator to be stored;

high-temperature tail gas generated during production sequentially passes through the uptake flue, the C3 suspension preheater, the C2 suspension preheater, the Venturi dryer and the C1 suspension preheater, the temperature of the high-temperature tail gas is gradually reduced to 300-350 ℃ when the high-temperature tail gas passes through the C1 suspension preheater, and then the high-temperature tail gas enters a waste gas treatment system.

The invention has the beneficial effects that: the existing production process is provided with a rotary dryer independently, and long-distance hot air pipelines are used for introducing hot air at the tail of a kiln head and a kiln into the rotary dryer to dry materials, wherein the temperature of the hot air is usually 120-150 ℃, and the drying effect is poor when the temperature is low. The waste gas after the material is dried is discharged into the atmosphere after being dedusted by the dedusting equipment, so that the equipment investment is high, the Venturi drying arranged at the preheater is used for drying the raw material, the structure is compact, the length of a hot air pipeline is greatly shortened, the dedusting equipment is not required to be additionally arranged, the equipment investment is greatly reduced, and meanwhile, the material is dried by using the flue gas temperature at the outlet of the C2 suspension preheater at 450-550 ℃, so that the material drying effect is better, and the heat exchange efficiency is higher; the invention is characterized in that a tertiary air inlet and a burner are arranged at the position of the uptake flue, the temperature of the preheater is improved by heat generated by fuel combustion, materials entering the kiln are improved to be more than 600 ℃ from 200-300 ℃ of the traditional production line, the heat exchange capability of the preheater is enhanced, the heat exchange time of the materials in the kiln is relatively reduced, the heat exchange efficiency is higher, the energy efficiency is lower, the yield is higher, a single-cylinder cooler is adopted for cooling materials leaving the kiln, compared with a grate cooler used in the existing production line, the structure is simple, the equipment maintenance amount is small, meanwhile, all cooling air of the materials enter the kiln, no residual air fan is needed, and the residual air fan is more suitable for cooling powdery materials.

Drawings

The invention will be further described with reference to the accompanying drawings in which:

FIG. 1 is a schematic view of the assembly structure;

in the figure: the kiln comprises a rotary kiln 1, a kiln tail smoke chamber 1.1, a kiln head burner 2, a primary fan 3, a single-cylinder cooler 4, a roller crusher 5, a zipper machine 6, a bucket lifter 7, an ascending flue 8, an ascending flue burner 9, a tertiary air duct 10, a C3 suspension preheater 11, a C1 suspension preheater 12, a C2 suspension preheater 13, a Venturi dryer 14, a rotary blanking device 15 and a hot blast stove 16.

Detailed Description

The present invention will be described in further detail with reference to the following examples and embodiments:

example 1

The kiln tail of the rotary kiln 1 is provided with a kiln tail smoke chamber 1.1, the rotary kiln 1 and the kiln tail smoke chamber 1.1 form a kiln body, a feeding and exhausting mechanism is arranged above the kiln body, a pipeline is arranged between the feeding and exhausting mechanism and the kiln body, an ascending flue 8 is arranged on the kiln tail smoke chamber 1.1, a tertiary air pipe 10 is arranged between the lower end of the ascending flue 8 and the kiln head cover air outlet of the rotary kiln 1, an ascending flue combustor 9 is arranged on the ascending flue 8 above the tertiary air pipe 10, the kiln head of the rotary kiln 1 is provided with a kiln head combustor 2, one side of the kiln head combustor 2 is provided with a primary air fan 3, an air supply pipeline is arranged between the air outlet of the primary air fan 3 and the air inlet of the kiln head combustor 2, one side of the front end of the rotary kiln 1 is provided with a single-cylinder cooler 4, a pipeline is arranged between the air outlet of the single-cylinder cooler 4 and the kiln head cover of the rotary kiln 1, a roller crusher 5 is arranged below the material outlet of, a bucket lift 7 is arranged at the tail end of the zipper machine 6;

the structure of the feeding and air exhausting mechanism is as follows: a C3 suspension preheater 11 is arranged on one side of the upper part of an uptake flue 8, a hot gas material mixing pipeline is arranged between an air outlet at the upper end of the uptake flue 8 and an air inlet at the upper end of the C3 suspension preheater 11, a feeding pipeline is arranged between a material outlet at the lower end of the C3 suspension preheater 11 and a material inlet of a kiln tail smoke chamber 1.1, a C2 suspension preheater 13 is arranged on one side above the C3 suspension preheater 11, a hot gas material mixing pipeline is arranged between an air outlet at the upper end of the C3 suspension preheater 11 and an air inlet of the C2 suspension preheater 13, a feeding pipeline is arranged between a material outlet at the lower end of the C2 suspension preheater 13 and a material inlet at the lower part of the uptake flue 8, a C1 suspension preheater 12 is arranged on one side above the C2 suspension preheater 13, a feeding pipeline is arranged between a material outlet at the lower end of the C1 suspension preheater 12 and the hot gas material mixing pipelines of, a hot gas and material mixing pipeline is arranged between an air inlet of the C1 suspension preheater 12 and an air outlet of the Venturi dryer 14, an air supply pipeline is arranged between an air outlet at the upper end of the C2 suspension preheater 13 and the lower end of the Venturi dryer 14, a hot air furnace 16 is arranged on one side of the lower end of the Venturi dryer 14, an air supply pipeline is arranged between an air outlet of the hot air furnace 16 and an air inlet at the lower end of the Venturi dryer 14, a rotary feeder 15 is arranged on one side of the Venturi dryer 14, and a feeding pipeline is arranged between a discharge outlet of the rotary feeder 15 and a feed inlet of the Venturi dryer 14.

Example 2

An air supply pipeline is arranged between an air outlet of the C1 suspension preheater 12 and a waste gas treatment system, during production, pulverized coal or natural gas is used as fuel of the kiln head burner 2, the uptake flue burner 9 and the hot blast stove 16, and spodumene powder with the granularity less than 0.5mm is used as raw material; spodumene powder enters the venturi dryer 14 through the rotary feeder 15, the hot air in the pipeline is used for drying materials, when the air temperature in the air supply pipeline at the initial feeding stage is too low, hot air generated by the hot air furnace 16 is used for drying the auxiliary raw materials, the spodumene powder enters the C1 suspension preheater 12 through the hot air material mixing pipeline at the upper part of the venturi dryer 14, preheating and gas-solid separation are carried out in the C1 suspension preheater 12, the spodumene solid particles after gas-solid separation move downwards and enter the hot air material mixing pipeline between the C3 suspension preheater 11 and the C2 suspension preheater 13 through the feeding pipeline, then the spodumene solid particles are sent into the C2 suspension preheater 13, preheating and gas-solid separation are carried out in the C2 suspension preheater 13, the spodumene solid particles after gas-solid separation move downwards and enter the rising flue 8 through the feeding pipeline for preheating, the spodumene solid particles in the rising flue 8 enter the C3 suspension preheater 11 through the hot air material mixing pipeline, preheating and gas-solid separation are carried out in a C3 suspension preheater 11, spodumene solid particles after gas-solid separation move downwards and enter a kiln tail smoke chamber 1.1 through a feeding pipeline to be calcined in a rotary kiln 1, the spodumene solid particles are calcined in the rotary kiln 1, the calcined crystal type converted clinker generated after calcining in the rotary kiln 1 enters a single-cylinder cooler 4 through a pipeline of a kiln hood of the rotary kiln 1 to be cooled, high-temperature air for cooling the clinker enters the rotary kiln 1 and a tertiary air pipe 10 through pipelines to respectively provide oxygen required by combustion for combustion in the rotary kiln 1 and a rising flue 8, the clinker cooled in the single-cylinder cooler 4 enters a roller crusher 5 to be crushed, the crushed clinker enters a bucket elevator 7 through a zipper elevator 6, and the crushed clinker is lifted through the bucket elevator 7 to enter a clinker storage;

the high-temperature tail gas generated in production sequentially passes through the uptake flue 8, the C3 suspension preheater 11, the C2 suspension preheater 13, the Venturi dryer 14 and the C1 suspension preheater 12, the temperature of the high-temperature tail gas is gradually reduced to 350 ℃ when the high-temperature tail gas passes through the C1 suspension preheater 12, and then the high-temperature tail gas enters a waste gas treatment system.

Claims

1. A method of operating a spodumene calcination conversion apparatus, said spodumene calcination conversion apparatus comprised of: the rotary kiln comprises a rotary kiln (1), a kiln tail smoke chamber (1.1), a kiln head burner (2), a primary fan (3), a single-cylinder cooler (4), a roller crusher (5), a zipper machine (6), a bucket lifter (7), a rising flue (8), a rising flue burner (9), a tertiary air duct (10), a C3 suspension preheater (11), a C1 suspension preheater (12), a C2 suspension preheater (13), a Venturi dryer (14), a rotary feeder (15) and a hot blast stove (16); the method is characterized in that: the kiln tail of the rotary kiln (1) is provided with a kiln tail smoke chamber (1.1), the rotary kiln (1) and the kiln tail smoke chamber (1.1) form a kiln body, a feeding and exhausting mechanism is arranged above the kiln body, a pipeline is arranged between the feeding and exhausting mechanism and the kiln body, an uptake flue (8) is arranged on the kiln tail smoke chamber (1.1), a tertiary air pipe (10) is arranged between the lower end of the uptake flue (8) and an air outlet of a kiln head cover of the rotary kiln (1), an uptake burner (9) is arranged on the uptake flue (8) above the tertiary air pipe (10), the kiln head of the rotary kiln (1) is provided with a kiln head burner (2), one side of the kiln head burner (2) is provided with a primary air fan (3), an air supply pipeline is arranged between an air outlet of the primary air fan (3) and an air inlet of the kiln head burner (2), one side of the front end of the rotary kiln (1) is provided with a single-cylinder cooler (4), and a pipeline is arranged between an air outlet of the rotary, a roller crusher (5) is arranged below the discharge opening of the single-cylinder cooler (4), a zipper machine (6) is arranged below the discharge opening of the roller crusher (5), and a bucket lift (7) is arranged at the tail end of the zipper machine (6);

the structure of the feeding and air exhausting mechanism is as follows: c3 suspension preheater (11) is arranged on one side of the upper part of the uptake (8), a hot gas material mixing pipeline is arranged between an air outlet at the upper end of the uptake (8) and an air inlet at the upper end of the C3 suspension preheater (11), a feeding pipeline is arranged between a material outlet at the lower end of the C3 suspension preheater (11) and a material inlet of a kiln tail smoke chamber (1.1), a C2 suspension preheater (13) is arranged on one side of the upper part of the C3 suspension preheater (11), a hot gas material mixing pipeline is arranged between an air outlet at the upper end of the C3 suspension preheater (11) and an air inlet of the C2 suspension preheater (13), a feeding pipeline is arranged between a material outlet at the lower end of the C2 suspension preheater (13) and a material inlet at the lower part of the uptake (8), a C1 suspension preheater (12) is arranged on one side of the upper part of the C2 suspension preheater (13), a material outlet at, Set up the pipeline of feeding between the hot gas material mixing pipeline of C2 suspension preheater (13), C1 suspension preheater (12) one side sets up venturi dryer (14), set up hot gas material mixing pipeline between the air intake of C1 suspension preheater (12) and the air exit of venturi dryer (14), set up the pipeline of supplying air between the air exit of C2 suspension preheater (13) upper end and venturi dryer (14) lower extreme, venturi dryer (14) lower extreme one side sets up hot-blast furnace (16), set up the pipeline of supplying air between the air exit of hot-blast furnace (16) and the air intake of venturi dryer (14) lower extreme, venturi dryer (14) one side sets up gyration tripper (15), set up the pipeline of feeding between the bin outlet of gyration tripper (15) and the feed inlet of venturi dryer (14).

2. The method of claim 1 for operating a spodumene calcination conversion unit, characterized in that: an air supply pipeline is arranged between an air outlet of the C1 suspension preheater (12) and a waste gas treatment system, during production, pulverized coal or natural gas is used as fuel of a kiln head burner (2), a rising flue burner (9) and a hot blast stove (16), and spodumene powder with the granularity of less than 0.5mm is used as a raw material; spodumene powder enters a Venturi dryer (14) through a rotary feeder (15), materials are dried by hot air in a pipeline, when the air temperature in an air supply pipeline at the initial feeding stage is too low, hot air generated by a hot air furnace (16) is used for assisting the drying of raw materials, the spodumene powder enters a C1 suspension preheater (12) through a hot air and material mixing pipeline at the upper part of the Venturi dryer (14), preheating and gas-solid separation are carried out in the C1 suspension preheater (12), spodumene solid particles after gas-solid separation move downwards and enter a hot air and material mixing pipeline between the C3 suspension preheater (11) and the C2 suspension preheater (13) through a feeding pipeline and then are fed into the C2 suspension preheater (13), preheating and gas-solid separation are carried out in the C2 suspension preheater (13), the spodumene solid particles after gas-solid separation move downwards and enter an ascending flue (8) through the feeding pipeline, spodumene solid particles in the uptake flue (8) enter a C3 suspension preheater (11) through a hot gas-material mixing pipeline, preheating and gas-solid separation are carried out in the C3 suspension preheater (11), the spodumene solid particles after gas-solid separation move downwards and enter a kiln tail smoke chamber (1.1) through a feeding pipeline to be calcined in a rotary kiln (1), the spodumene solid particles are calcined in the rotary kiln (1) to generate clinker after being calcined, the clinker after being calcined in the rotary kiln (1) enters a single-cylinder cooler (4) through a pipeline of a kiln head cover of the rotary kiln (1) to be cooled, high-temperature air for cooling the clinker enters the rotary kiln (1) and a tertiary air pipe (10) through pipelines to respectively provide oxygen required by combustion in the rotary kiln (1) and the uptake flue (8), the clinker after being cooled by the single-cylinder cooler (4) enters a roller crusher (5) to be crushed, the crushed clinker enters a bucket elevator (7) through a zipper machine (6), the crushed clinker is lifted into a clinker storage through a bucket lifter (7) to be stored;

high-temperature tail gas generated during production sequentially passes through a rising flue (8), a C3 suspension preheater (11), a C2 suspension preheater (13), a Venturi dryer (14) and a C1 suspension preheater (12), and the temperature of the high-temperature tail gas is gradually reduced to 300-350 ℃ when the high-temperature tail gas passes through the C1 suspension preheater (12), and then the high-temperature tail gas enters a waste gas treatment system.