CN116697604B

CN116697604B - Hot-blast stove device with gangue calcining function and use method

Info

Publication number: CN116697604B
Application number: CN202310926780.1A
Authority: CN
Inventors: 张乾; 薛斌; 王奇; 黄伟; 李向阳; 李乐; 张宝霖
Original assignee: Taiyuan University of Technology
Current assignee: Taiyuan University of Technology
Priority date: 2023-07-26
Filing date: 2023-07-26
Publication date: 2025-08-15
Anticipated expiration: 2043-07-26
Also published as: CN116697604A

Abstract

The invention discloses a hot blast furnace device with a coal gangue calcining function and a using method thereof, and the hot blast furnace device comprises a shell, wherein an insulating layer is arranged on the outer side of the shell, a tail gas treatment section, a coal gangue feeding section, a high-temperature calcining section and a discharging section are arranged in the shell from top to bottom, a tail gas inlet is arranged on one side of the upper part of the tail gas treatment section, a hot air outlet is arranged on the other side of the upper part of the tail gas treatment section, coal gangue nozzles are symmetrically arranged below the tail gas inlet and the hot air outlet, a flame distributor is arranged at the bottom of the high-temperature calcining section, a grate is arranged at the lower side of the flame distributor, and the bottom of the discharging section is connected with an ash closing lock bin. The hot blast stove device with the function of calcining the coal gangue and the use method thereof adopt the structure, utilize the heat energy in the coal gangue while realizing the calcining and activating of the coal gangue, save the gas fuel consumption, replace the function of the traditional hot blast stove, have high heat energy efficiency and wide application prospect.

Description

Hot-blast stove device with gangue calcining function and use method

Technical Field

The invention relates to the technical field of hot blast furnace equipment, in particular to a hot blast furnace device with a gangue calcining function and a using method thereof.

Background

The hot blast stove is a thermal equipment integrating combustion and heat transfer processes. The hot blast stove generates high-temperature hot air by burning fuel, and is used for supplying heat energy required in industrial production, such as heating tail gas, drying, sintering and the like. In the process of purifying the coke oven combustion tail gas or blast furnace gas combustion tail gas, the tail gas temperature is not matched with the proper temperature of the desulfurization and denitration process catalyst, so that the tail gas is heated by adopting a hot blast stove to control the temperature, thereby being beneficial to realizing the downstream high-efficiency desulfurization and denitration. The hot blast stove generally adopts blast furnace gas or coke oven gas as fuel, adopts a method of preheating combustion air and gas under the condition of only using the blast furnace gas according to the process requirements, and controls the temperature in the hot blast stove by adjusting the fuel supply quantity, the air temperature and other parameters of a combustor. According to the heat accumulator in the hot blast stove, the ball type hot blast stove and the lattice brick hot blast stove can be divided into top combustion, internal combustion and external combustion according to the combustion mode.

The traditional hot blast stove is used as equipment for heating a medium by using hot air generated by fuel combustion, and is widely applied to the fields of metallurgy, chemical industry, building materials, food processing and the like. It has disadvantages including 1) high energy consumption, typically low energy efficiency of the stove, and partial fuel energy being discharged as flue gas. This means that the stove wastes a certain amount of energy during use. 2) The temperature is not easy to control, the temperature regulation of the traditional hot blast stove is relatively difficult, and particularly for a large hot blast stove. This may lead to large temperature fluctuations during heating, affecting product quality or process stability. 3) The operation cost of the hot blast stove comprises fuel cost, maintenance cost, labor cost and the like. Especially for older stoves, higher operating costs may result due to technology updates and lower energy efficiency. 4) Potential safety hazards, namely, the hot blast stove relates to working environments such as high temperature, high pressure and the like, and if the operation is improper or equipment maintenance is not in place, potential safety hazards such as explosion, leakage and the like can exist.

The gangue is a co-associated mineral of coal, and is generated in the process of coal exploitation and washing and is the main waste discharged in the process of coal exploitation and washing and selecting. The gangue can be converted into usable rubber filler, soil conditioner or building material by heat activation. However, because the heat value of the gangue is low, when the gangue is placed in a kiln for calcination and activation, the gangue is difficult to realize full calcination and activation only by virtue of the heat value of the gangue. In addition, the coal gangue causes a great amount of heat loss in the calcining and cooling processes, and partial coal gangue is insufficiently calcined due to uneven temperature in the furnace, so that the ideal activation temperature is difficult to reach, and the product quality is affected.

Aiming at the problems existing in the conventional hot blast stove and the gangue calcination and activation process, the invention discloses a hot blast stove device with the function of calcining and activating the gangue and a using method thereof.

Disclosure of Invention

The invention aims to provide a hot blast stove device with a coal gangue calcining function and a using method thereof, which utilize heat energy in the coal gangue while realizing the calcining and activating of the coal gangue, save the gas fuel consumption, replace the functions of the existing hot blast stove, and have high heat energy efficiency and wide application prospect.

In order to achieve the aim, the invention provides a hot blast stove device with a gangue calcining function, which comprises a shell, wherein an insulating layer is arranged on the outer side of the shell, a manhole is arranged at the top of the shell, and a tail gas treatment section, a gangue feeding section, a high-temperature calcining section and a discharging section are arranged in the shell from top to bottom;

Wherein one side of the upper part of the tail gas treatment section is provided with a tail gas inlet which is connected with a tail gas pipeline, a hot air outlet is arranged on the other side of the upper part of the tail gas treatment section, and the hot air outlet is connected with the cyclone separator through a pipeline;

coal gangue nozzles are symmetrically arranged below the tail gas inlet and the hot air outlet of the coal gangue feeding section;

The bottom of the high-temperature calcining section is provided with a flame distributor, the flame distributor is connected with a gas pipeline through a flange, the lower side of the flame distributor is provided with a grate, and the bottom of the grate is connected with the shell through a driver;

The bottom of the discharging section is connected with the ash locking bin, and air inlets are symmetrically arranged on two sides of the ash locking bin at the bottom of the discharging section.

Preferably, the heat-insulating layer is a heat-insulating brick with the thickness of 10-20 cm.

Preferably, the flame distributor is a cross-shaped, grid-shaped or rotary-shaped flame distributor, and when the flame distributor is a cross-shaped flame distributor, the flame holes are evenly distributed at the top of the flame distributor.

Preferably, the grate is a pagoda-shaped rotary grate comprising 4-8 layers of grate blocks and top hoods which are sequentially overlapped into a ladder cone shape.

Preferably, the upper part, the middle part, the lower part and the hot air outlet of the shell are respectively provided with a temperature detection device and a pressure detection device.

Preferably, the air inlet is connected with the induced draft fan through a pipeline.

Preferably, the particle size of the ground coal gangue is less than or equal to 50mm.

The application method of the hot blast stove device with the gangue calcining function comprises the following steps of:

1) Air enters from an air inlet and passes through a fire grate to reach a flame distributor, fuel and air are fully mixed at the flame distributor, high-temperature smoke and flame smoke are generated at the point of the flame distributor, and heat of the smoke is transferred to the air;

2) Grinding the coal gangue, enabling the ground coal gangue to enter the shell through a coal gangue nozzle, calcining and activating the coal gangue through high-temperature flue gas and air in the falling process, and stopping the coal gangue which is not completely activated in the falling process at a grate for continuous calcining and activating;

3) The tail gas enters the shell through the tail gas inlet at the tail gas treatment section, the combustion reaction is carried out by high-temperature flue gas and air in the rising process, and the burnt tail gas enters the cyclone separator through the hot air outlet for dust removal treatment;

4) And the activated gangue falls into a lower ash locking bin through the rotation of the grate and is periodically discharged.

The invention has the beneficial effects that:

1. The hot blast stove device provided by the invention has the advantages of simple structure and lower production cost, and the overhaul holes are formed above the hot blast stove, so that the equipment is convenient to overhaul and replace.

2. The hot blast stove device combines mechanical crushing and high-temperature calcination activation, so that the residual heat value of the coal gangue is fully utilized, one part is used for self calcination activation, the other part is used for heating air and tail gas, and the high-efficiency utilization of energy is realized.

3. The hot blast stove device provided by the invention removes harmful substances and generates partial heat energy by introducing the tail gas with higher upstream temperature into the hot blast stove for combustion reaction. The tail gas is heated to a certain temperature in a heat exchange mode and then is sent to a downstream desulfurization and denitrification process, so that the effects of environmental protection and pollutant emission reduction are achieved.

4. The cross-shaped distributor in the hot blast stove device can uniformly distribute flame, prevent the combustion flame from being too concentrated, ensure that the temperature in the stove is more uniform, avoid the phenomenon of damage caused by nonuniform heating of the stove liner, and change the flame distributor into a grid type or a rotary type according to different requirements.

5. The hot blast stove device is not limited to use of coal gangue for calcining, and other raw materials with low carbon content and heat value can be calcined and activated in the device, so that the gas fuel consumption is saved.

The technical scheme of the invention is further described in detail through the drawings and the embodiments.

Drawings

FIG. 1 is a schematic view of an embodiment of a stove assembly with gangue calcination function according to the present invention;

FIG. 2 is a schematic diagram of a flame distributor of a hot blast stove device with gangue calcination function according to the present invention.

Reference numerals:

1. The device comprises a shell, a manhole, a heat preservation layer, a tail gas inlet, a hot air outlet, a cyclone separator, a coal gangue nozzle, a flame distributor, a flame hole, a fire grate, a closed ash lock bin, an air inlet, a driver and a driver, wherein the shell is provided with the manhole, the heat preservation layer, the tail gas inlet, the hot air outlet, the cyclone separator, the coal gangue nozzle, the flame distributor, the flame hole, the fire grate, the ash lock bin and the driver.

Detailed Description

The invention will be further described with reference to examples. Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The above-mentioned features of the invention or the features mentioned in the specific examples can be combined in any desired manner, and these specific examples are only intended to illustrate the invention and are not intended to limit the scope of the invention.

Example 1

The gangue materials of this example are provided by Dagaohe thermoelectric company, and the chemical composition of the gangue is shown in Table 1.

TABLE 1 chemical composition of gangue

The experimental parameters are that the particle size of the gangue is 0-20 mm, the temperature of a high-temperature calcination section is 950 ℃, the residence time of the gangue in a furnace is about 1h, and the temperature of a hot air outlet is 900 ℃.

Referring to fig. 1 to 2, as shown in the drawings, the invention provides a hot blast stove device with a gangue calcining function, which comprises a shell 1, wherein an insulating layer 3 is arranged on the outer side of the shell 1, and the insulating layer 3 is an insulating brick with the thickness of 10cm, so that a good insulating effect is achieved, and heat loss is reduced. The top of casing 1 is equipped with manhole 2, makes things convenient for the equipment to overhaul and changes.

The inside top-down of casing 1 sets up to tail gas treatment section, gangue feeding section, high temperature calcination section and ejection of compact section. Wherein, upper portion one side of tail gas treatment section is provided with tail gas inlet port 4, and tail gas inlet port 4 is connected with the tail gas pipeline, and upper portion opposite side of tail gas treatment section is provided with hot air outlet 5, and hot air outlet 5 passes through the pipeline to be connected with cyclone 6, and the pipeline that hot air outlet 5 connects needs to be built by laying bricks or stones with high-quality refractory material because being in the high temperature state all the time. The tail gas enters the shell 1 through the tail gas inlet 4, the high-temperature flue gas and air in the shell 1 are used for carrying out combustion reaction, harmful substances in the tail gas are removed, partial heat energy is generated, then the tail gas after the harmful substances are removed, namely hot air, enters the cyclone separator 6 through the hot air outlet 5, the cyclone separator 6 is used for separating solid particles in the hot air, and the purified hot air enters the downstream process. The cyclone separator 6 needs to be subjected to heat preservation treatment to prevent heat loss.

Coal gangue nozzles 7 are symmetrically arranged below the tail gas inlet 4 and the hot air outlet 5 of the coal gangue feeding section, and the ground coal gangue enters the shell 1 through the coal gangue nozzles 7, so that coal gangue particles are uniformly distributed in the shell 1 of the hot air furnace device.

The bottom of the high-temperature calcination section is provided with the flame distributor 8, the flame distributor 8 is connected with a gas pipeline through a flange, the flame distributor 8 is a cross-shaped flame distributor 8, flame holes 9 are evenly distributed at the top of the flame distributor 8, the cross-shaped flame distributor can evenly distribute flame, the combustion flame is prevented from being too concentrated, the temperature in the furnace is more uniform, and the phenomenon of damage caused by nonuniform heating of a furnace liner can be avoided.

The lower side of the flame distributor 8 is provided with a fire grate 10, the bottom of the fire grate 10 is connected with the convex edge of the shell 1 through a carrier roller and a track, one side of the shell 1 is also provided with a driver 13 connected with the fire grate 10, and the driver 13 mainly comprises a motor, a speed reducer, an eccentric sleeve assembly, an output shaft and the like. The speed reducer is connected with the variable frequency speed regulating motor through the shaft coupling, and the output shaft of speed reducer passes through coupling assembling and is connected with one side of grate 10, through variable frequency speed regulating motor drive speed reducer, and the speed reducer gives grate 10 with power transmission, provides power for the rotation of grate 10 to driver 13 realizes the accurate control to the grate 10 rotational speed through the frequency of changing variable frequency speed regulating motor, satisfies continuous production's needs. The grate 10 is a pagoda-shaped rotary grate comprising four layers of sequentially overlapped stepped conical grate 10 blocks and a top hood, five layers of the grate 10 being provided, the grate 10 being driven by a grate 10 driver 13. The coal gangue which is not fully activated in the falling process can fall to the grate 10 for a part of time to continue calcination and activation, and the activated coal gangue falls into the ash locking bin 11 below through the rotation of the grate 10.

The bottom of the discharging section is connected with the ash closing lock bin 11, and air inlets 12 are symmetrically arranged on two sides of the ash closing lock bin 11 at the bottom of the discharging section. The air inlet 12 is connected with the induced draft fan through a pipeline, and bottom air is pumped by the induced draft fan, so that the frequency of the induced draft fan can be changed according to the downstream process and the requirement of gangue activation, and the required air quantity is provided.

The upper part, the middle part, the lower part and the hot air outlet 5 of the shell 1 are respectively provided with a temperature detection device and a pressure detection device, so that the temperature and the pressure conditions of the hot air furnace device can be conveniently monitored.

1) Air enters through the grate 10 from the air inlet 12 to the flame distributor 8 where the fuel is thoroughly mixed with the air and high temperature flue gas and flame flue gas are generated at a point where the heat of the flue gas is constantly transferred to the air.

2) The coal gangue is ground and then enters the shell 1 through the coal gangue nozzle 7, the coal gangue is calcined and activated through high-temperature flue gas and air, the particle size of the ground coal gangue is less than or equal to 20mm, and the coal gangue can be uniformly distributed into the furnace when entering the furnace body through the coal gangue nozzle 7 due to the small particle size of the coal gangue, and the coal gangue is calcined and activated through high-temperature flue gas and air. Due to the influence of gravity, the coal gangue can be fully calcined and activated while falling, and part of the coal gangue which is not fully activated in the falling process falls to the grate 10 to stay for continuous calcination and activation.

3) The tail gas at the tail gas treatment section enters the shell 1 through the tail gas inlet 4, the combustion reaction is carried out through high-temperature flue gas and air in the rising process, harmful substances are removed, and the burnt tail gas enters the cyclone separator 6 through the hot air outlet 5 for dust removal treatment and then is sent to the downstream desulfurization and denitrification process.

4) The activated gangue falls into the lower ash locking bin 11 through the rotation of the grate 10 and is periodically discharged.

Performance testing

The mechanical properties of the rubber materials are tested by filling the rubber materials with the activated coal gangue powder calcined by the hot blast stove device, and the test results are shown in Table 2. The comparative examples are unactivated gangue powder and carbon black.

Table 2 tensile Properties and hardness of the samples

Example 2

The production area of the gangue material of the embodiment is Shanxi yangquan, and the chemical composition of the gangue is shown in table 3.

TABLE 3 chemical composition of gangue

The experimental parameters are that the particle size of the coal gangue is 0-35 mm, the temperature of a high-temperature calcination section is 968 ℃, the residence time of the coal gangue in a furnace is about 1h, and the temperature of a hot air outlet is 905 ℃.

2) The coal gangue is ground and then enters the shell 1 through the coal gangue nozzle 7, the coal gangue is calcined and activated through high-temperature flue gas and air, the particle size of the ground coal gangue is less than or equal to 35mm, and the coal gangue can be uniformly distributed into the furnace when entering the furnace body through the coal gangue nozzle 7 due to the small particle size of the coal gangue, and the coal gangue is calcined and activated through high-temperature flue gas and air. Due to the influence of gravity, the coal gangue can be fully calcined and activated while falling, and part of the coal gangue which is not fully activated in the falling process falls to the grate 10 to stay for continuous calcination and activation.

Performance testing

The mechanical properties of the rubber materials are tested by filling the rubber materials with the activated coal gangue powder calcined by the hot blast stove device, and the test results are shown in Table 4. The comparative examples are unactivated gangue powder and carbon black.

Table 4 tensile Properties and hardness of the samples

After the rubber material is filled with the coal gangue powder calcined and activated by the hot blast stove device in the embodiment 1-2, the mechanical property of the rubber material is obviously improved, and the performance of the rubber material is equivalent to that of the carbon black modified filled rubber material. The performance of the rubber material filled with the unmodified coal gangue powder is obviously reduced. Therefore, the coal gangue powder which is calcined and activated by the hot blast stove device provided by the invention with low price can be used for replacing expensive carbon black, so that the high value-added utilization of the coal gangue is realized, and the production cost of rubber and plastic materials is reduced. In addition, the activated gangue can be used as an adsorbent and a plastic filler, and can also be used for producing building materials, thereby having wide market prospect.

It should be noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted by the same, and the modified or substituted technical solution may not deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A hot blast furnace device capable of calcining coal gangue, characterized in that it comprises a housing, an insulation layer provided on the outside of the housing, an access hole provided on the top of the housing, and an exhaust gas treatment section, a coal gangue feeding section, a high-temperature calcining section, and a discharge section arranged from top to bottom within the housing;

A tail gas inlet is provided on one side of the upper portion of the tail gas treatment section, which is connected to the tail gas pipeline; a hot air outlet is provided on the other side of the upper portion of the tail gas treatment section, which is connected to the cyclone separator through a pipeline;

The gangue feeding section is located below the tail gas inlet and hot air outlet and is symmetrically provided with gangue nozzles;

A flame distributor is provided at the bottom of the high-temperature calcining section, which is connected to the gas pipeline through a flange. A grate is provided on the lower side of the flame distributor, and the bottom of the grate is connected to the shell through a driver.

The bottom of the discharging section is connected to the ash-closing lock bin, and the bottom of the discharging section is symmetrically provided with air inlets on both sides of the ash-closing lock bin.

2. A hot blast furnace device with the function of calcining coal gangue according to claim 1, characterized in that the insulation layer is an insulation brick with a thickness of 10-20 cm.

3. A hot blast furnace device with the function of calcining coal gangue according to claim 1, characterized in that the flame distributor is cross-shaped, grid-shaped or rotary-shaped, and when the flame distributor is a cross-shaped flame distributor, the flame holes are evenly distributed on the top of the flame distributor.

4. A hot blast furnace device with the function of calcining coal gangue according to claim 1, characterized in that the grate is a pagoda-shaped rotating grate comprising 4-8 layers of grate blocks stacked in a stepped cone shape and a top hood.

5. A hot blast furnace device with the function of calcining coal gangue according to claim 1, characterized in that temperature detection devices and pressure detection devices are provided on the upper, middle, lower part and hot blast outlet of the shell.

6. The hot air furnace device with the function of calcining coal gangue according to claim 1, characterized in that the air inlet is connected to the induced draft fan through a pipeline.

7. A method for using the hot blast furnace device having the function of calcining coal gangue according to any one of claims 1 to 6, characterized in that it comprises the following steps:

1) Air enters from the air inlet, passes through the grate and reaches the flame distributor, where the fuel and air are fully mixed and ignited to produce high-temperature flue gas and flames, and the heat of the flue gas is transferred to the air;

2) The gangue is ground and then enters the shell through the gangue nozzle. During the falling process, the gangue is calcined and activated by high-temperature flue gas and air. The gangue that is not fully activated during the falling process falls to the grate and stays there for further calcination and activation;

3) In the exhaust gas treatment section, the exhaust gas enters the shell through the exhaust gas inlet, and heat is exchanged between the high-temperature flue gas and the air during the rising process. The exhaust gas after heat exchange enters the cyclone separator through the hot air outlet for dust removal;

4) After activation, the gangue falls into the ash lock bin below through the rotation of the grate and is discharged periodically.

8. The method for using a hot blast furnace device capable of calcining coal gangue according to claim 7, wherein the particle size of the coal gangue after grinding is less than or equal to 50 mm.