CN103547656B - Apparatus and method for drying coking coal - Google Patents

Abstract

Provided are an apparatus and method for drying coking coal. The apparatus for drying coking coal includes: a flow layer dryer through which coal passes and is dried by hot air ejected through a distributor installed therein; a coal supply part connected to the flow layer dryer so as to feed the coal to the distributor; and a hot-air supply part connected to the flow layer dryer so as to supply hot air to the distributor. Here, at least two or more flow layer dryers may be provided and connected in series so as to allow the coal to sequentially pass through the flow layer dryers, thereby drying the coal.

Description

Apparatus and method for drying coke

technical field

The present invention relates to a technique for drying coal charged into a coke oven to produce coke. More specifically, the present invention relates to a device and method for drying coke that can improve coal drying efficiency.

Background technique

As global crude steel production has increased dramatically, so has demand for coal, which is used to make iron ore and coke for metallurgy. For this reason, coal prices have skyrocketed, concerns about resource depletion and the difficulty of securing high-quality caking coal have gradually deepened. Under such circumstances, various technologies are being developed and applied to diversify the coal used to manufacture metallurgical coke and to increase the use ratio of non-caking coal with weak caking force.

Among these techniques, a drying technique for reducing the moisture content of coal charged into a coke oven is mainly used as a coal pretreatment technique. In moisture drying of coal, fluidized bed dryers with excellent drying efficiency are mainly used. In a fluidized bed dryer, coal is fluidized and dried with hot air.

Fig. 14 shows a coal drying structure using a prior art fluidized bed dryer. In the prior art, in order to dry coal, a horizontally arranged fluidized bed dryer 100 with a long and narrow structure is used. Hot air for drying coal is supplied from the lower portion of the fluidized bed dryer 100 . Therefore, coal is loaded from the front end of one side of the fluidized bed dryer, moves in the horizontal direction, and is dried through the fluidization process. Moreover, the dried granular activated carbon is discharged from the front end on the other side of the fluidized bed dryer, and the pulverized coal produced during the coal drying process is classified from the dried coal and discharged from the upper part. The graded pulverized coal is press-molded in a molding device 110 into a predetermined shape. The molded pulverized coal is mixed with granular activated carbon dried in the fluidized bed dryer 100, and then supplied into a coke oven to manufacture coke.

However, since hot air is dispersed and fed along the fluidized bed dryer in the structure of the above-mentioned prior art, when high-moisture coal containing a lot of moisture is fed into the fluidized bed dryer, there is a problem that the fluidized bed dryer It is not easy to form a fluidized bed of coal at the supply location. Therefore, the drying operation by coal fluidization cannot be performed smoothly.

Also, since the coal drying and classification are performed in one fluidized bed dryer in the above-mentioned prior art structure, the classification efficiency is lowered. In particular, there is a problem in that classification of pulverized coal is intensively performed at a discharge point of dried coal, and the classification efficiency of pulverized coal is lowered.

In addition, since hot air of the same temperature is supplied to both the coal supply position and the coal discharge position of the fluidized bed dryer in the structure of the prior art described above, coal drying efficiency and energy efficiency are lowered. That is, at the position where coal is supplied to the fluidized bed dryer, high-moisture coal is brought into contact with hot air at low temperature. Also, at the coal discharge position of the fluidized bed dryer, the dried coal is brought into contact with hot air of the same temperature at an elevated temperature. In the structure of the prior art, the hot air is not dispersed effectively, resulting in a reduction in the drying efficiency of the coal and a waste of energy.

Moreover, for the coal drying method in the prior art, since high-temperature hot air should be supplied to the fluidized bed dryer, a lot of energy is consumed to supply the hot air. Therefore, there is a problem that environmental pollution becomes more serious due to discharge of pollutants such as carbon dioxide.

In addition, the structure of the powdered coal compacted and molded by the molding device in the coal drying process in the prior art, the powdered coal produced in the fluidized bed dryer at 80 to 350°C, and the tar and pitch used as the binding material were checked. A base binder is mixed and the mixture is thermocompressed to produce briquettes of coal.

For the pulverized coal classified in the fluidized bed dryer, its moisture content is very low and its particle size is very small, so its own bulk density (bulk density) is low. Therefore, in the prior art structure, when a binder is mixed for compacting pulverized coal, a problem occurs that it is difficult to mix with the binder. Also, in the process of press-forming by a forming device, press-forming is performed for improving bulk density, and in this case, it is difficult to press and convey pulverized coal. In addition, since pulverized coal is mixed with a binder for hot press molding, there are problems in that the temperature of the pulverized coal and the molding machine should be maintained, and tar is generated due to thermal decomposition of coal.

Therefore, there is an urgent need to develop a more efficient and economical technique for drying coal for coke production.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Contents of the invention

The present invention aims to provide a method and device for drying coke that can improve coal drying efficiency.

In addition, the present invention also aims to provide a method and device for drying coke that can improve the classification efficiency of pulverized coal produced in the coal drying process.

In addition, the present invention also aims to provide a method and device for drying coke that can improve the flow efficiency of high-moisture coal.

In addition, the present invention also aims to provide a method and apparatus for drying coke that uses waste gas generated in a coke oven as a heat source for a fluidized bed dryer to save energy and minimize environmental pollution.

In addition, the present invention also aims to provide a method and apparatus for drying coke that minimizes environmental pollution caused by dust by treating the dust in exhaust gas generated in a coke oven.

In addition, the present invention also aims to provide a method and device for drying coke that can more easily compact the pulverized coal produced in the coal drying process to agglomerate into coal briquettes.

In addition, the present invention also aims to provide a method and apparatus for drying coke that improves workability by pressing pulverized coal at room temperature.

An exemplary embodiment of the present invention provides a device for drying coke, including: a fluidized bed dryer, the fluidized bed dryer fluidizes and dries coal by hot air, and the hot air passes through the The dispersion plate in the fluidized bed dryer is sprayed out; the coal supply part is connected to the fluidized bed dryer to charge coal to the dispersion plate; and the hot air supply part is connected to the hot air supply part The fluidized bed dryer is used to supply hot air to the dispersion plate; wherein at least two fluidized bed dryers are provided and connected in sequence so that the coal passes through each fluidized bed dryer in sequence and is dried.

Multiple fluidized bed dryers can be installed in multiple stages, and along the moving path of the coal, between the outlet of one fluidized bed dryer and the inlet of the next fluidized bed dryer can be installed for moving coal the connecting pipe.

The drying device of the present invention may include: a first fluidized bed dryer, which is used to fluidize and dry coal to classify coal; and a second fluidized bed dryer, which The second fluidized bed dryer is connected to the first fluidized bed dryer to fluidize and dry the coal passing through the first fluidized bed dryer to classify the coal.

In at least one of the fluidized bed dryers, the coal supply direction and the hot air supply direction may be opposite to each other.

At least one of said fluidized bed dryers may be arranged vertically to charge coal from above to below.

The temperature or flow rate of the hot air supplied to each of the fluidized bed dryers may be different for each fluidized bed dryer.

The fluidized bed dryer may include: a dispersing plate; a lower chamber arranged at the lower part of the dispersing plate and connected to a hot air supply part to introduce hot air; and a main tower, the The main tower is vertically arranged on the dispersing plate, and is used for coal fluidization, and an inlet for coal flowing into it and an outlet for discharging dried coal are formed on the side of the main tower.

The hot air supply part may include: a blower installed in a hot air duct connected to a lower chamber of the fluidized bed dryer to supply hot air; a heater installed on the hot air duct to heat the supplied hot air; and a flow meter installed on the hot air pipe to control the flow of hot air supplied to the fluidized bed dryer.

In the drying device of the present invention, at least one of the fluidized bed dryers may further include a circulation part that makes the flow rate of the hot air blown out through the dispersion plate different at the central part and the peripheral part of the dispersion plate, so that Coal is recycled.

The circulation part may be installed in the frontmost fluidized bed dryer among fluidized bed dryers connected in sequence.

The circulation part may include a separation pipe installed in a lower chamber formed at a lower portion of a dispersion plate of the fluidized bed dryer to divide the lower chamber so as to be independent from a central portion and a peripheral portion of the dispersion plate. supply hot air, and the hot air supply part may include a central hot air pipe and a peripheral hot air pipe, the central hot air pipe is connected to the separation pipe, and supplies hot air to the central part of the dispersion plate through the separation pipe, and the peripheral hot air pipe It is connected to the lower chamber and supplies hot air to the peripheral part of the diffuser plate through the outside of the separation pipe, thereby supplying hot air with different flow rates to the central hot air duct and the peripheral hot air duct respectively.

In the circulation part, a flow velocity of the hot air supplied to the central part of the dispersion plate may be greater than a flow velocity of the hot air supplied to the peripheral part.

The flow velocity of the hot air supplied to the central portion of the dispersion plate may be 5-8 times the minimum fluidization velocity of coal.

The flow velocity of the hot air supplied to the peripheral portion of the dispersion plate may be 1 to 2 times the minimum fluidization velocity of coal.

The circulation part may further include a cylindrical pipe installed at an upper part of a central part of the dispersion plate in the fluidized bed dryer at a distance from the dispersion plate.

The size of the cylindrical tube may be 1/2-1/4 of the inner diameter of the fluidized bed dryer.

The separation tube may have a size equivalent to the cylindrical tube.

The hot air supply part may include: a branch pipe installed in the exhaust gas discharge pipe connecting the coke oven combustion chamber and the flue to supply the exhaust gas as hot air for the coal dryer; and a blower installed in the branch pipe to supply exhaust gas.

The present device may further include a dust collecting part installed on the branch pipe to treat dust contained in the exhaust gas.

The dust collecting part may include: at least one cyclone separator installed on the branch pipe; a main valve installed on the discharge pipe to open and close the discharge pipe to The branch pipe conveys exhaust gas; and a branch valve installed on the branch pipe to open and close the branch pipe.

The hot air supply part may include: a bypass pipe for connecting the discharge duct and the blower; and a bypass valve installed on the bypass pipe to open and close A bypass pipe, whereby the exhaust gas selectively passes through the dust collecting portion.

The drying device of the present invention may also include a coal briquette making machine, which is connected to the fluidized bed dryer and used to briquette classified pulverized coal, wherein the coal briquette making machine may Comprising: a pulverized coal hopper for storing pulverized coal classified in said fluidized bed dryer; a coal hopper for storing undried coal; a binder hopper for storing binder; a mixer, connected to each hopper for mixing pulverized coal, coal and binder; and a forming machine connected to said mixer for forming the mixture into coal briquettes.

The apparatus may include a pulverized coal mixing tank connected to the pulverized coal hopper to discharge pulverized coal from the pulverized coal hopper in a predetermined ratio and transfer it to the mixer.

The apparatus may include a coal mixing tank connected to the coal hopper to discharge coal in predetermined proportions from the coal hopper and transfer it to the mixer.

The apparatus may include a binder mixing tank connected to the binder hopper to discharge binder from the binder hopper in a predetermined ratio and transfer it to the mixer.

In the device of the present invention, based on 100% by weight of the mixed raw material of pulverized coal and coal, the content of coal that can be included is 10-40% by weight.

In the device of the present invention, based on 100 parts by weight of the mixed raw material of pulverized coal and coal, the binder may be included in an amount of 4-8 parts by weight.

Another exemplary embodiment of the present invention provides a method for drying coke by supplying hot air into a fluidized bed dryer to fluidize and dry coal, the method comprising: sequentially passing coal through multiple Stage-connected fluidized bed dryers are used to dry the coal sequentially.

The drying method of the present invention may include: a first drying step of fluidizing and drying the coal through a first fluidized bed dryer to classify the coal; In the dryer, the coal dried in the first drying step is fluidized and dried to classify it.

In each drying step, the flow rate of hot air supplied to the fluidized bed dryer may be 0.6˜1.0 m/sec (meter/second).

In each drying step, the temperature of the hot air supplied to the fluidized bed dryer may be 120 to 200°C.

In the first drying step, the supply amount of coal charged into the first fluidized bed dryer may be 20 kg/h or less.

The temperature or flow rate of the hot air in the first step may be different from the temperature or flow rate of the hot air in the second step.

The temperature of the hot air in the first step may be relatively higher than the temperature of the hot air in the second step.

The flow velocity of the hot air in the first step may be relatively smaller than the flow velocity of the hot air in the second step.

In the drying method for drying coke of the present invention by supplying hot air into a fluidized bed dryer to fluidize dry coal, by making the flow rate of the hot air supplied to the central part of the dispersion plate of the fluidized bed dryer Different from the flow velocity of the hot air supplied to the peripheral portion of the diffuser plate, the coal can be circulated and dried.

In the drying method of the present invention, the flow velocity of the hot air supplied to the center portion of the dispersion plate may be greater than the flow velocity of the hot air supplied to the peripheral portion.

In the drying method of the present invention, the flow velocity of the hot air supplied to the central part of the dispersion plate may be 5-8 times the minimum fluidization velocity of coal.

In the drying method of the present invention, the flow velocity of the hot air supplied to the peripheral portion of the dispersion plate may be 1 to 2 times the minimum fluidization velocity of coal.

The drying method of the present invention for drying coal by supplying hot air into a fluidized bed dryer may be a method in which exhaust gas discharged from a combustion chamber of a coke oven is supplied into the fluidized bed dryer to dry coal to dry.

The drying method of the present invention may further include a dust removal step of removing dust contained in the exhaust gas during supply of the exhaust gas to the dryer.

The drying method of the present invention may be a method in which coal is fluidized in a fluidized bed dryer to be dried, and the coal is sequentially passed through the fluidized bed dryers connected in multiple stages to be sequentially dried.

The drying method of the present invention may also include the step of pressing and molding the pulverized coal discharged during the coal drying process, wherein the pulverized coal molding step may include: by mixing the mixed raw material of pulverized coal and undried coal with a binder, to prepare the mixture; and to manufacture coal briquettes by pressing the prepared mixture.

The coal briquette manufacturing step may be performed at room temperature.

The binder may be at least one selected from asphalt, tar, syrup or glycerin.

Based on 100 parts by weight of the mixed raw material of pulverized coal and coal, the binder may be included in an amount of 4-8 parts by weight.

The coal may be included in an amount of 10 to 40% by weight based on the mixed raw material.

According to an exemplary embodiment of the present invention, coal may be dried by forming a multi-stage fluidized bed, thereby gradually drying and classifying coal, thereby improving drying efficiency and classifying efficiency.

Also, by changing the operating conditions in accordance with the moisture content of coal, etc., it is possible to prevent coal coalescence therein, and to improve flow efficiency even for high-moisture coal.

In addition, energy can be saved and environmental pollution can be minimized by using exhaust gas generated in a coke oven as a heat source for the fluidized bed dryer.

Also, dust in the exhaust gas generated in the coke oven can be treated, so that environmental pollution and flue pollution due to the dust generated with the discharge of the exhaust gas in the prior art can be minimized.

In addition, the formability of pulverized coal can be improved by mixing pulverized coal generated during the coal drying process with undried coal to press into agglomerates.

Furthermore, the pulverized coal is compacted at room temperature, thereby further simplifying the operating device and improving operability.

As described above, by improving the coal drying efficiency, the charge density of coal charged into the coke oven can be increased, and the coke quality can be improved.

Also, using the pulverized coal generated in the coal drying process and using the agglomerated pulverized coal by agglomerating the pulverized coal generated in the coal drying process can increase the charge density of coal charged into a coke oven and improve coke quality.

In addition, the use ratio of low-priced low-rank coal can be greatly improved, and coke oven operation can be maintained stably.

Description of drawings

FIG. 1 is a schematic structural view illustrating an apparatus for drying coal according to a first exemplary embodiment of the present invention.

2 to 4 are graphs illustrating experimental results of drying characteristics of coal in the apparatus for drying coal of the first exemplary embodiment of the present invention.

5 and 6 are graphs illustrating experimental results of pulverized coal classification characteristics in the apparatus for drying coal of the first exemplary embodiment of the present invention.

FIG. 7 is a schematic structural view illustrating an apparatus for drying coal according to a second exemplary embodiment of the present invention.

FIG. 8 is a sectional view along line A-A of FIG. 5 of an apparatus for drying coal according to a second exemplary embodiment of the present invention.

FIG. 9 is a schematic diagram for explaining the operation of an apparatus for drying coal according to a second exemplary embodiment of the present invention.

FIG. 10 is a schematic diagram showing an apparatus for drying coal according to a third exemplary embodiment of the present invention.

11 is a schematic view showing a coal briquette making machine of an apparatus for drying coal according to a fourth exemplary embodiment of the present invention.

FIG. 12 is a graph illustrating an experiment result of a binder molding ratio with respect to a mixing amount when pulverized coal is compacted by a coal briquette manufacturing machine according to a fourth exemplary embodiment of the present invention.

FIG. 13 is a graph illustrating experimental results of coal briquette strength with respect to coal mixing amount when pulverized coal is compacted by a coal briquette manufacturing machine according to a fourth exemplary embodiment of the present invention.

Figure 14 is a schematic diagram illustrating a prior art apparatus for drying coal.

Detailed ways

The present invention is described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown so as to be readily understood by those skilled in the art. As is easily understood by those skilled in the art to which the present invention pertains, the exemplary embodiments described below can be modified into various forms without departing from the spirit and scope of the present invention. Where possible, the same or similar parts are denoted by using the same reference numerals in the drawings.

All terms used herein including technical terms and scientific terms have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. The previously defined terms are understood to have meanings consistent with relevant technical documents and currently disclosed contents, but cannot be interpreted as having ideal or very formal meanings unless they are defined.

Hereinafter, an exemplary embodiment of the present invention will be described based on an exemplary embodiment applied to drying of coal for a coke oven. However, the present invention is not limited thereto, and is applicable to drying of various raw materials including coal for various purposes.

[First Exemplary Embodiment]

FIG. 1 illustrates an apparatus for drying coal of a first exemplary embodiment.

As shown in the figure, the apparatus of the present invention includes fluidized bed dryers 10 and 11 , a coal supply part 20 , and hot air supply parts 30 and 31 . Furthermore, the present device further includes a coal briquette manufacturing machine 60 for pressing pulverized coal particles (hereinafter referred to as pulverized coal) produced during the coal drying process into briquettes.

The coal supply part 20 is connected to the fluidized bed dryer 10 to charge the dispersion plate 12 with coal. The hot air supply parts 30 and 31 are connected to lower parts of the fluidized bed dryers 10 and 11 to supply hot air to the dispersion plate 12 .

Also, the fluidized bed dryers 10 and 11 fluidize and dry the coal by hot air sprayed through the dispersion plate 12 installed in the fluidized bed dryers 10 and 11 .

In the present exemplary embodiment, two fluidized bed dryers 10 and 11 are provided, and the two fluidized bed dryers are connected in multiple stages. Hereinafter, for the convenience of description, according to the moving sequence of coal, the preceding fluidized bed dryer is referred to as the first fluidized bed dryer 10, and the fluidized bed dryer connected to the back of the first fluidized bed dryer is referred to as the first fluidized bed dryer. The machine is called the second fluidized bed dryer 11.

In this exemplary embodiment, the first fluidized bed dryer 10 and the second fluidized bed dryer 11 are arranged in sequence, and the outlet 18 of the first fluidized bed dryer 10 and the second fluidized bed dryer 11 A connecting pipe 19 for moving coal is installed between the inlets 17 of the coal mine.

The first fluidized bed dryer 10 is vertically arranged, and a dispersion plate 12 that sprays hot air to the upper part is installed at the lower part of the first fluidized bed dryer. A lower chamber 14 is formed on the lower portion of the dispersion plate 12, and the lower chamber 14 is connected to a hot air supply part 30 to introduce hot air. Moreover, a main tower 16 for coal drying is arranged vertically on the dispersion plate 12 . An inlet 17 for charging coal and an outlet 18 for discharging coal dried in the fluidized bed are installed on the side of the main tower 16 . In addition, a cyclone separator 50 is connected to and installed on the upper part of the main tower 16, and the cyclone separator 50 is used for collecting pulverized coal generated during the coal drying process. In order to prevent heat loss, heat insulating material is applied on the outer surface of the fluidized bed dryers 10 and 11, and the fluidized bed dryers 10 and 11 have thermocouples and pressure sensors to detect the temperature in the fluidized bed and stress.

The structure of the second fluidized bed dryer 11 is the same as that of the first fluidized bed dryer 10 described above. Therefore, the same reference numerals denote the same elements, and detailed description thereof will be omitted hereinafter. In addition, the second fluidized bed dryer 11 is connected to the hot air supply part 31, and the coal is fluidized and dried by the supplied hot air. In this exemplary embodiment, the hot air supply parts 30 and 31 are independently installed in the first fluidized bed dryer and the second fluidized bed dryer, respectively, so as to individually supply hot air to each fluidized bed dryer.

The coal supply part 20 quantitatively transports the coal contained in the hopper 22 through a screw feeder 24 at the lower end of the hopper 22 , and supplies it to the main tower 16 of the first fluidized bed dryer 10 . A chute 26 connected to the coal inlet 17 of the main tower 16 is installed on the discharge side of the screw feeder 24 . Thus, the coal conveyed by the screw feeder 24 is loaded into the main column 16 through the chute 26 . In order to make the coal flow smoothly, in the coal supply part 20 , a stirrer may be further installed in the hopper 22 .

In this exemplary embodiment, since the second fluidized bed dryer 11 receives the coal dried through the fluidization process in the first fluidized bed dryer 10 through the connecting pipe 19, no separate coal supply section.

The hot air supply part 30 includes a blower 34 and a heater 36, the blower 34 is installed in the hot air pipeline 32 connected to the lower chamber 14 of the first fluidized bed dryer 10 for supplying hot air, the heating A device 36 is installed on the hot air duct 32 for heating the supplied hot air. Moreover, a flow meter 38 is installed on the hot air duct 32, and the flow meter 38 is used to control the flow rate of the supplied hot air. The hot air may be air heated by the heater 36 or high-temperature gas generated in a steel plant, such as exhaust gas discharged from a coke oven combustion chamber, but is not particularly limited thereto. When the exhaust gas exhausted from the coke oven combustion chamber is used as hot air, since it is not necessary to heat the hot air, a heater may not be included in the hot air supply section. This structure will be described in detail below.

The hot air supply part 31 connected to the second fluidized bed dryer 11 to supply hot air to the second fluidized bed dryer has the same structure as the hot air supply part 30 connected to the first fluidized bed dryer 10 . Therefore, the same reference numerals denote the same elements as those of the hot air supply part 30, and detailed description thereof will be omitted hereinafter.

In the above structure, hot air is introduced into the lower chambers 14 of the fluidized bed dryers 10 and 11 through the blower 34 . The high-temperature gas flowing into the lower chamber 14 is sprayed to the upper part through the dispersion plate 12 installed on the upper part of the lower chamber 14 . The hot wind sprayed on the upper part by the diffuser plate 12 forms an upward airflow. A fluidized bed is formed above the dispersion plate 12 by this updraft. Coal flows in this fluidized bed and is dried by hot air. The coal dehydrated by drying splashes above the fluidized bed and is discharged through the outlet 18 installed on the side of the main tower 16 . Furthermore, pulverized coal generated during the drying process splashes to the upper part of the main tower 16 and is collected by the cyclone separator 50 . The fine pulverized coal not collected by the cyclone separator 50 is collected by the post-filter 52 connected to the cyclone separator 50 . The pulverized coal collected by the cyclone separator 50 and the post-filter 52 is pressed into a block by the coal briquetting machine 60, and then loaded into the coke oven together with the dried coal passed through the drying device.

As mentioned above, the device has two fluidized bed dryers arranged in multiple stages, and the coal is dried and classified sequentially through the two fluidized bed dryers. Hereinafter, classification refers to the separation of pulverized coal from undried coal.

Hereinafter, the operation of this device is explained.

The coal supplied to the first fluidized bed dryer 10 through the coal supply part 20 is subjected to first fluidized drying in the first fluidized bed dryer 10 by hot air. This fluidized bed dryer has a vertical structure. Therefore, the coal is charged in the direction opposite to the direction in which the hot air is sprayed to the top of the distribution plate. The coal charged in this way flows up and down in the main tower to form a fluidized bed by the flow of hot air blown to the top of the diffuser plate. That is, a fluidized bed is formed vertically by the upward flow of the coal which has fallen by its own weight and the hot air sprayed to the upper part. In the fluidized bed formed in the vertical direction in the main tower, the coal is concentrated and continuously injected with hot air to flow. Therefore, compared with the structure in which coal moves in a horizontal direction and is blown by hot air in the prior art, the drying efficiency of coal by hot air can be improved.

In this exemplary embodiment, the first fluidized bed dryer 10 mainly performs the drying function of coal. Classification of pulverized coal is performed in the first fluidized bed dryer 10, but the classification efficiency does not need to be particularly high. The pulverized coal produced and graded in the first fluidized bed dryer 10 rises to the upper part, and is collected and processed through the cyclone separator 50 and post filter 52 connected to the upper part.

In order to strengthen the drying function of coal in the first fluidized bed dryer 10, the temperature of the hot air supplied to the first fluidized bed dryer 10 can be set to be higher than that supplied to the second fluidized bed dryer 11 The temperature of the hot air.

The coal dried in the fluidized bed of the first fluidized bed dryer 10 and splashed above the fluidized bed is discharged through the outlet 18 of the first fluidized bed dryer 10 . The coal discharged from the first fluidized bed dryer 10 is charged into the second fluidized bed dryer 11 through the connecting pipe 19 connected to the outlet 18 of the first fluidized bed dryer 10 .

The coal flowing into the second fluidized bed dryer 11 through the connecting pipe 19 is fluidized by hot air on the dispersion plate 12 of the second fluidized bed dryer 11 and undergoes a second drying process. The coal dried in the second fluidized bed dryer 11 and splashed above the fluidized bed is discharged to the outside through the outlet 18 of the second fluidized bed dryer 11 . Furthermore, the pulverized coal generated in the second fluidized bed dryer 11 is classified from the coal, moved to the upper part, and collected and processed by the cyclone separator 50 and the post filter 52 connected to the upper part.

In this exemplary embodiment, the second fluidized bed dryer 11 re-dries the first-dried coal passed through the first fluidized bed dryer, and mainly performs the function of classifying pulverized coal. When the coal passes through the second fluidized bed dryer 11, the coal is dried to ensure the required moisture content and the pulverized coal is sufficiently classified.

In order to strengthen the classification function of pulverized coal in the second fluidized bed dryer 11, the flow rate of the hot air supplied to the second fluidized bed dryer 11 can be set to be greater than that supplied to the first fluidized bed dryer. The flow rate of the hot air of machine 10.

As described above, the coal is dried in multiple stages by two separate fluidized bed dryers, so that drying and grading of the coal can be performed independently. Therefore, drying efficiency and classification efficiency of coal can be improved.

Meanwhile, FIGS. 2 to 4 illustrate experimental results of coal drying characteristics by the multistage fluidized bed dryer of the present exemplary embodiment.

The experiments were performed on coal blends commonly used to make metallurgical coke. The coal blend was prepared by mixing multiple single coal types, and the results of industrial chemical analysis, elemental analysis, calorific value and surface area analysis of the coal blend are shown in Table 1 below.

[Table 1]

Since the coal blend comprises 9-10% moisture and has a very small surface area as shown in Table 1 above, most of the moisture is surface moisture present on the surface.

In this experiment, the drying operation of the coal blend, as in this exemplary embodiment, was performed by a drying apparatus having a first fluidized bed dryer and a second fluidized bed dryer. The undried coal blend was charged to the first fluidized bed dryer, and the moisture of the dried coal blend finally discharged from the second fluidized bed dryer was tested. The particle size of the coal blend charged to the first fluidized bed dryer was selected to obtain a size of 7mm or less and a moisture content of 9.2-9.4%.

FIG. 2 illustrates experimental results of changes in coal moisture when the flow rate and temperature of hot air in the apparatus for drying coal according to the present exemplary embodiment are changed.

Experiments were conducted by changing the flow rate and temperature of hot air supplied to each fluidized bed dryer in a state where the supply amount of the coal admixture charged to the first fluidized bed dryer was fixed at 20 kg/h. When the minimum fluidization velocity (Qmf) of coal is 1, use its multiple to represent the flow velocity of hot air. The minimum fluidization velocity is the minimum velocity for the coal particles to flow and is about 0.12m/sec. In the following description, since the minimum fluidization velocity is represented by 1Qmf, which is about 0.12m/sec, the flow velocity of hot air which is 5 times the minimum fluidization velocity is defined as 0.6m/sec, which is 8 times the minimum fluidization velocity The velocity of the hot air is defined as 1.0m/sec.

As shown in Fig. 2, the experimental results show that when the flow rates of the hot air are the same as each other, the moisture of the coal blend shows a decrease as the temperature of the hot air increases. Also, when the temperatures of the hot air are the same as each other, the moisture of the coal blend shows a decrease as the flow rate of the hot air increases.

Therefore, it was confirmed from the experimental results that, for coal blends with a moisture content of 9.2 to 9.4%, when the temperature of the hot air sent to each fluidized bed dryer is 120°C or higher and the flow rate of the hot air is 5 times the minimum fluidization velocity or higher, the coal blend can be finally dried to have a moisture content of 5% or less of what the coal blend would be useful for coking. Also, it can be seen that when the temperature of the hot air is above 160°C and the flow velocity of the hot air is 7 times or more the minimum fluidization velocity, the moisture of the coal blend can be finally dried to have a moisture content of 2% or lower.

When the temperature of the hot air is lower than 120°C, the drying efficiency of the coal blend decreases, and as the temperature of the hot air increases, the drying efficiency increases, but it is worth noting that an increase in the temperature of the hot air will lead to energy waste. In particular, the coal blend is obtained by blending coals having a broad volatile content ranging from low to high volatile, wherein a high volatile coal with a volatile content of 30% when in an inert atmosphere When heated above 200°C, it will thermally decompose and begin to release some volatile components. Therefore, when drying the coal blend, it is preferable to keep the temperature of the hot air at 200° C. or lower in order to prevent deterioration of the coal. Therefore, in this exemplary embodiment, the temperature of the hot air may be set within a range of 120-200°C.

In addition, in the case where the flow rate of the hot air is less than 5 times the minimum fluidization velocity, the drying efficiency of the coal admixture is reduced, and if the flow rate is more than 8 times, no specific increase effect is clearly shown. Therefore, in this exemplary embodiment, the flow velocity of the hot air may be set to be about 5-8 times the minimum fluidization velocity, ie, 0.6-1.0 m/sec.

FIG. 3 illustrates experimental results of changes in coal moisture when the flow rate of hot air and the supply amount of coal admixture are changed in the apparatus for drying coal of the present exemplary embodiment.

The experiment was carried out by changing the supply amount of the coal admixture charged into the first fluidized bed dryer and the flow rate of the hot air while keeping the temperature of the hot air constant at 120°C.

As shown in Figure 3, the experimental results show that when the flow rates of the hot air are the same as each other, as the supply of coal admixture loaded into the first fluidized bed dryer increases, the coal finally discharged from the second fluidized bed dryer Coal blend moisture was shown to increase. Also, when the supply amounts of the coal admixture are the same as each other, the moisture of the coal admixture shows an increase in the case where the flow rate of the hot air is small.

Therefore, it was confirmed from the experimental results that for coal blends with a moisture content of 9.2 to 9.4%, when the flow rate of the hot air fed into each fluidized bed dryer is 5 times or more When the coal blend supplied to the fluidized bed dryer is 20 kg/h or less, the coal blend can be finally dried to have a moisture content of 5% or less than when the coal blend can be used for coke. Also, it can be seen that when the flow rate of the hot air is 7 times the minimum fluidization velocity or higher and the supply amount of the coal admixture charged into the first fluidized bed dryer is 15 kg/h or lower, the coal admixture The mixture can be finally dried to have a moisture content of 2% or less.

If the supply of the coal admixture exceeds 20kg/h, since the drying efficiency of the coal admixture is reduced, the flow rate of the hot air should be increased, and it is noteworthy that the energy consumption increases.

In addition, FIG. 4 illustrates changes in coal moisture when coal supply and hot air temperature are changed in the apparatus for drying coal of the present exemplary embodiment.

Experiments were conducted by changing the supply amount of the coal admixture supplied to the first fluidized bed dryer and the temperature of the hot air in a state where the flow rate of the hot air was fixed at 5 times the minimum fluidization velocity.

As shown in Figure 4, the experimental results show that at the same hot air temperature, as the supply of coal blends into the first fluidized bed dryer increases, the coal finally discharged from the second fluidized bed dryer The blend moisture showed an increase. Also, when the supply amounts of the coal blends were the same as each other, the moisture of the coal blends showed a decrease as the temperature of the hot air increased.

Therefore, it was confirmed by the experimental results that, for coal blends with a moisture content of 9.2 to 9.4%, the temperature of the hot air sent to each fluidized bed dryer is 120°C or higher and the first fluidized bed is dried When the feed rate of the coal blend to the machine is 20 kg/h or less, the coal blend is finally dried to have a moisture content of 5% or less than when the coal blend is usable for coke. Also, it can be seen that when the flow rate of the hot air is 7 times the minimum fluidization velocity or higher and the supply of the coal blend charged into the first fluidized bed dryer is kept at 20 kg/h or lower, the coal The blend can be finally dried to have a moisture content of 2% or less.

Meanwhile, FIGS. 5 and 6 illustrate experimental results of pulverized coal classification characteristics by the multistage fluidized bed dryer of the present exemplary embodiment. The experimental conditions are the same as those of the coal drying characteristic experiment.

FIG. 5 illustrates experimental results of fractionation ratios of pulverized coal when the flow rate and temperature of hot air are changed in the apparatus for drying coal of the present exemplary embodiment.

Experiments were conducted by changing the flow rate and temperature of hot air supplied to each fluidized bed dryer in a state where the supply amount of the coal admixture charged to the first fluidized bed dryer was fixed at 20 kg/h.

As shown in Figure 5, the experimental results show that when the hot air velocity is the same as each other, as the temperature of the hot air increases, the fractionation rate of pulverized coal increases, while at the same hot air temperature, as the velocity of the hot air grading rates showed improvement.

In addition, FIG. 6 illustrates experimental results of the classification rate of pulverized coal when the coal supply amount and hot air temperature are changed in the apparatus for drying coal of the present exemplary embodiment.

Experiments were conducted by changing the supply amount of the coal admixture supplied to the first fluidized bed dryer and the temperature of the hot air in a state where the flow rate of the hot air was fixed at 5 times the minimum fluidization velocity.

As shown in Fig. 6, the experimental results show that at the same hot air temperature, as the supply of coal admixture loaded into the first fluidized bed dryer increases, the classification rate of pulverized coal shows a decrease. Also, when the supply amounts of the coal blends were the same as each other, the fractionation rate of pulverized coal was shown to increase as the temperature of the hot air increased.

As described above, it was confirmed from the experimental results of the pulverized coal classification ratio that the pulverized coal classification ratio having a sufficient required value can be ensured by the fluidized bed dryer of the present invention.

[Second Exemplary Embodiment]

Figure 7 illustrates another exemplary embodiment of the apparatus of the present invention for drying coal. In the following description, the same reference numerals denote the same elements as described above, and detailed description thereof will be omitted.

As shown in the figure, the device of the present invention includes a first fluidized bed dryer 10 and a second fluidized bed dryer 11 arranged in multiple stages, a coal supply for charging coal to the first fluidized bed dryer Part 20 , hot air supply parts 30 and 31 connected to the fluidized bed dryer 10 and supplying hot air to the dispersion plate 12 . And, the device of the present invention also includes a circulation part, which makes the flow velocity of the hot air sprayed out through the dispersion plate 12 of the fluidized bed dryer 10 different at the central part and the peripheral part of the dispersion plate 12, so that Coal circulates on top of the dispersion plate 12 . Wherein, the central part refers to the central part including the center of the dispersion plate 12, and the peripheral part refers to the outer part of the central part.

The circulation section can be installed in both dryers. In the present exemplary embodiment, the circulation section is installed on the first fluidized bed dryer 10 arranged in front of the two dryers arranged in multiple stages.

In the circulation part, a separating pipe 40 dividing the lower chamber 14 is installed in the lower chamber 14 to independently supply hot air to the central part and the peripheral part of the dispersion plate 12, and from the hot air supply part 30 to the The inside and outside of the separating pipe 40 are supplied with hot air at different flow rates.

The hot air duct 32 for supplying hot air from the hot air supply part 30 to the lower chamber 14 is divided into two, which are respectively connected and installed to the separating pipe 40 and the lower chamber 14 . Among the hot-air ducts 32 , the hot-air duct connected to the separating pipe 40 is called the central hot-air duct 33 , and the hot-air duct connected to the lower chamber 14 is called the peripheral hot-air duct 35 .

The hot air supply part 30 supplies hot air at different flow rates to the central hot air duct 33 and the peripheral hot air duct 35 . In the present exemplary embodiment, the hot air supply part 30 supplies hot air such that the flow velocity of the hot air supplied to the central portion of the dispersion plate 12 is greater than that supplied to the peripheral portion. The flow rate of the hot air can be controlled by the flow meter 38 of the hot air supply part 30 . The hot air is supplied according to the flow rate by controlling or confirming the flow meter 38 installed on each hot air duct 32 .

Therefore, hot air with different flow rates is sprayed to the central part and peripheral part of the distribution plate 12, so that the coal rises in the central part of the distribution plate 12 and descends in the peripheral part, thereby circulating.

Here, the flow velocity of the hot air supplied to the central portion of the dispersion plate 12 may be 5-8 times the minimum fluidization velocity of coal. Also, the flow velocity of the hot air supplied to the peripheral portion of the dispersion plate 12 may be 1 to 2 times the minimum fluidization velocity of coal. If the flow velocity of the hot air supplied to the central portion of the dispersing plate 12 is lower than the above velocity, the coal cannot be sufficiently raised, and thus the circulation of the coal cannot be sufficiently performed. If the flow velocity of the hot air supplied to the central portion of the diffuser plate is greater than the range, power for supplying the hot air increases to increase operating costs.

In addition, if the flow velocity of the hot air supplied to the peripheral portion of the diffuser plate 12 is greater than the range, the speed difference between the above-mentioned flow velocity and the flow velocity of the hot air supplied to the central portion of the diffuser plate becomes small, so that the circulation of coal cannot be performed smoothly, thereby A phenomenon in which coal falls to the peripheral portion and accumulates occurs.

In the device of the present invention, a cylindrical pipe 42 is also installed in the main tower 16 of the fluidized bed dryer 10 so as to form the circulating flow on the upper part of the dispersing plate 12 more reliably. The cylindrical pipe 42 is a cylindrical pipe structure vertically arranged in the main tower 16 along the length direction of the main tower 16 , and is installed on the upper part of the central part of the dispersion plate 12 at a distance from the dispersion plate 12 .

Therefore, the fluidized bed formed on the upper part of the dispersing plate 12 is clearly divided into two regions by the cylindrical pipe 42, namely, a central part and a peripheral part on the outside thereof. Accordingly, a coal circulation flow that rises in the cylindrical pipe 42 and descends outside the cylindrical pipe 42 can be reliably formed.

As shown in FIG. 8 , the cylindrical pipe 42 is arranged in the central part of the main tower 16, and is fixedly installed on the main tower 16 by using a support member 44 in a state where the cylindrical pipe is separated from the dispersion plate 12. on the inner peripheral surface.

In this exemplary embodiment, the size of the cylindrical pipe 42 is 1/2˜1/4 of the inner diameter of the fluidized bed dryer 10 . Also, the separation pipe 40 may have a size equivalent to the cylindrical pipe 42 . In the case where the inner diameter of the cylindrical pipe is smaller than the range, the inner diameter of the cylindrical pipe is too small, so it is noteworthy that the hot air supplied to the central portion is discharged to the outside of the cylindrical pipe. Also, if the inner diameter of the cylindrical tube is larger than the range, the inner diameter of the cylindrical tube is too large, so it is noticeable that the rising coal then descends through the inside of the cylindrical tube. Therefore, the circulation of coal cannot be performed sufficiently.

Hereinafter, the operation of the apparatus of the present invention will be described with reference to FIG. 9 .

The device of the present invention supplies hot air with different flow rates through the central hot air duct 33 and the peripheral hot air duct 35 .

The hot air supplied to the central hot air duct 33 is connected to the separation pipe 40 and supplied into the separation pipe 40 . The separation pipe 40 is connected to the central part of the dispersion plate 12 , and the hot air flowing into the separation pipe 40 is sprayed toward the central part of the dispersion plate 12 . Therefore, hot air with a relatively high flow velocity is sprayed toward the central portion of the dispersion plate 12 .

The hot air supplied to the peripheral hot air duct 35 is connected to the lower chamber, and is supplied between the outside of the separation pipe 40 and the lower chamber 14 . The area between the separation pipe 40 and the lower chamber 14 is connected to the peripheral portion of the diffuser plate 12 , and the hot air flowing into the area is sprayed out through the peripheral portion of the diffuser plate 12 . Therefore, hot air having a relatively low flow velocity is sprayed toward the peripheral portion of the dispersion plate 12 .

As described above, hot air with a relatively high flow velocity is ejected toward the central portion of the diffuser plate 12 , while hot air with a relatively low flow velocity is ejected toward the peripheral portion of the diffuser plate 12 . Therefore, a circulating flow flowing from the central portion of the dispersion plate 12 to the peripheral portion is generated. The coal rises in the central part of the distribution plate 12 along with the circulating flow. The ascending coal ascends through the inside of the cylindrical pipe 42 arranged on the upper part of the dispersion plate 12 . And, if coal passes through the upper part of cylindrical pipe 42, the lifting force becomes weaker, then the coal is squeezed to the outside of cylindrical pipe 42, and passes through the outside of cylindrical pipe 42—the peripheral portion of dispersing plate 12 where the flow velocity is relatively low. --decline.

Thus, as shown, a circulating flow is formed whereby the coal rises along the interior of the cylindrical tube 42 and descends through the area between the cylindrical tube 42 and the inner surface of the main tower 16, with the coal following this circulating flow in the cylindrical Circulation is carried out in the pipe 42.

Therefore, when the coal containing excessive moisture is charged into the fluidized bed dryer 10, in the prior art, the coal adheres to the dispersion plate 12, so it is difficult to form and make the coal flow, but in the device of the present invention, the circulation is ensured. Flow in which the coal rises at the central portion of the dispersion plate 12 due to the high flow velocity direction and descends at the peripheral portion of the dispersion plate 12. With this circulating flow, the coal can continue to go down and dry outside the cylindrical tube 42 and go up and dry inside the cylindrical tube 42 . Therefore, even for high-moisture coal, the coal can be circulated in the fluidized bed, thereby improving the drying efficiency.

[Third Exemplary Embodiment]

Figure 10 illustrates another exemplary embodiment of the apparatus of the present invention for drying coal. In the following description, the same reference numerals denote the same elements as described above, and detailed description thereof will be omitted.

As shown in the figure, the device of the present invention includes a first fluidized bed dryer 10 and a second fluidized bed dryer 11 arranged in multiple stages, a coal supply part for charging coal into the first fluidized bed dryer 20. A hot air supply part 70 connected to the fluidized bed dryers 10 and 11 and supplying hot air to the dispersion plate 12.

In the present exemplary embodiment, the structure of the hot air supply portion 70 for supplying hot air to the respective fluidized bed dryers 10 and 11 is as follows.

In the present exemplary embodiment, in the hot air supply part 70 , exhaust gas discharged from the coke oven combustion chamber 100 in which coal is carbonized is supplied to the fluidized bed dryers 10 and 11 .

For this reason, the hot air supply part 70 of the present invention includes: a branch pipe 71, which is installed in the waste gas discharge pipe 102 connecting the coke oven combustion chamber 100 and the flue 104 to supply waste gas as hot air for the coal dryer; blower 72 , the blower 72 is installed in the branch pipe 71 to supply exhaust gas to the lower part of the fluidized bed dryer; and a hot air duct 73 connecting the blower 72 and the lower part of the fluidized bed dryer.

Therefore, in the drying apparatus of the present invention, coal can be dried by using exhaust gas generated in the coke oven combustion chamber 100 as hot air.

Here, the drying device of the present invention further includes a dust collecting part installed on the branch pipe 71 to process the dust contained in the exhaust gas.

The dust collection part includes: at least one cyclone separator 80 installed in the branch pipe 71 to collect dust contained in the exhaust gas; a main valve 81 installed in the The discharge pipe 102 is used to open and close the discharge pipe 102 so as to deliver exhaust gas to the branch pipe 71 ; the branch valve 82 is installed in the branch pipe 71 to open and close the branch pipe 71 .

Therefore, if necessary, if the main valve 81 installed in the discharge pipe 102 is closed and the branch valve 82 installed in the branch pipe 71 is opened, the exhaust gas discharged to the flue 104 is supplied to the branch pipe 71 . Therefore, the exhaust gas can be supplied as hot air of the fluidized bed dryers 10 and 11 after the exhaust gas passes through the dust collecting part and the dust is removed.

In addition, if necessary, the device of the present invention further includes: a bypass pipe 84, which connects the discharge pipe 102 and the blower 72 so as to directly supply the exhaust gas through the blower 72; and a bypass valve 86, which A bypass valve 86 is installed on the bypass pipe 84 to open and close the bypass pipe 84 so that exhaust gas selectively passes through the dust collecting part.

In this exemplary embodiment, the bypass pipe 84 is installed between the rear end of the cyclone separator 80 and the blower 72 to be connected with the discharge pipe 102 . Therefore, according to the opening and closing operations of the branch valve 82 and the bypass valve 86 installed in the branch pipe 71 or the bypass pipe 84, the exhaust gas selectively passes through the dust collecting portion. Wherein, the main valve 81 is arranged at the rear end of the bypass pipe 84 on the discharge pipe 102 .

In addition, the device of the present invention may also include: a discharge pipe 88, the discharge pipe 88 is connected to the outlet side of the blower 72 and the discharge pipe 102; a discharge valve 89, the discharge valve 89 is installed in the discharge pipe 88; the pipe valve 74 , the pipeline valve 74 is installed in the hot air pipeline 73 so that the dust-treated waste gas can be discharged through the flue 104 if necessary. Therefore, if necessary, if the duct valve 74 is closed and the discharge valve 89 is opened, exhaust gas is supplied to the discharge duct 102 to be discharged through the flue 104 .

At this time, since the exhaust gas discharged through the flue 104 passes through the cyclone separator 80 of the dust collection part to remove dust, the pollution of the flue 104 caused by dust such as graphite contained in the exhaust gas can be prevented.

In the following, the operation of the device of the present invention is explained.

As mentioned above, in the apparatus of the present invention, two fluidized bed dryers 10 and 11 arranged in multiple stages are provided, and coal is dried and classified sequentially when passing through the two fluidized bed dryers.

Here, see the process of supplying hot air into said fluidized bed dryer, for the carbonization of coal in the coke oven, by-products such as COG (Coke Oven Gas) and BFG (Blast Furnace Gas) Gas)) gas is supplied to the combustion chamber 100 for combustion. The heat generated in the combustion chamber 100 is used for carbonization of coal. The exhaust gas produced after combustion in the combustion chamber 100 is discharged to the flue 104 through the exhaust pipe 102 connected with the combustion chamber 100 .

During this process, the device of the present invention is driven to use the exhaust gas discharged to the flue 104 as hot air for the fluidized bed dryers 10 and 11 .

The exhaust gas discharged from the coke oven combustion chamber 100 has a temperature of 200-230° C. and a flow rate of 6000 Nm ³ /min, and the exhaust gas contains a small amount of dust, so it is sufficient to be used as a hot air source for a fluidized bed dryer.

When the main valve 81 installed on the discharge pipe 102 is closed and the branch valve 82 installed on the branch pipe 71 is opened, exhaust gas discharged from the combustion chamber 100 through the discharge pipe 102 flows into the branch pipe 71 . In this state, if the blower 72 is driven, the exhaust gas undergoes dust treatment in the cyclone 80 and is then supplied to each of the fluidized bed dryers 10 and 11 through the hot air duct 73 connected to the blower 72 . Therefore, the exhaust gas is used as hot air for the fluidized bed dryer.

As described above, through the hot air supply part 70 of the present invention, exhaust gas discharged from the coke oven combustion chamber 100 can be used as hot air of the fluidized bed dryer to dry coal.

Here, the initial temperature of the exhaust gas discharged from the combustion chamber is 200˜230° C., and the temperature decreases when the exhaust gas passes through the above process, so when the exhaust gas is supplied to the fluidized bed dryers 10 and 11, the supply temperature of the exhaust gas can be 200°C or lower. Therefore, coal can be dried without deterioration of coal and additional emission of _CO2 .

[Fourth Exemplary Embodiment]

Figure 11 illustrates another exemplary embodiment of the apparatus for drying coal of the present invention. In the following description, the same reference numerals denote the same elements as described above, and detailed description thereof will be omitted.

As shown in the figure, the device of the present invention includes a first fluidized bed dryer 10 and a second fluidized bed dryer 11 arranged in multiple stages, a coal supply part for charging coal into the first fluidized bed dryer 20. Hot air supply parts 30 and 31 connected to the fluidized bed dryer 10 to supply hot air to the dispersion plate 12. Moreover, the apparatus of the present invention further includes a coal briquette maker 60, which is connected to the fluidized bed dryers 10 and 11 to briquette pulverized coal produced during the coal drying process.

In the present exemplary embodiment, the structure of the coal briquette manufacturing machine 60 is as follows.

The coal briquette manufacturing machine 60 of the present invention mixes pulverized coal produced during the drying process of coal loaded into a coke oven with undried coal and a binder, and briquettes the mixture, thereby manufacturing coal briquettes P .

The pulverized coal classified in the fluidized bed dryers 10 and 11 is collected by the cyclone separator 50 and the post filter 52 .

The pulverized coal classified in the fluidized bed dryers 10 and 11 and collected by the cyclone separator 50 and the post filter 52 is transferred and stored in the pulverized coal hopper 61 . In addition, undried coal is transferred and stored into the coal hopper 62 without passing through the fluidized bed dryer to be stored. Also, the binder mixed with the mixed raw material of pulverized coal and coal is stored in the binder hopper 63 for preparation.

The coal briquette manufacturing machine 60 includes: a mixer 64 connected to each hopper to mix pulverized coal, coal and binder; and a molding machine 65 connected to the mixer To make coal briquettes P from the mixed mixture.

Wherein, there is a mixing tank between each funnel and the mixer, and the mixing tank is used to discharge pulverized coal, coal and binder to the mixer according to the mixing ratio. That is, the pulverized coal stored in the pulverized coal hopper 61 is transferred to the mixer 64 at a predetermined ratio through the pulverized coal mixing tank 90 . The coal stored in the coal hopper 62 is transferred to the mixer 64 through the coal mixing tank 91 at a predetermined ratio. And, the adhesive stored in the adhesive hopper 63 is transferred to the mixer 64 at a predetermined ratio through the adhesive mixing tank 92 .

The mixer 64 uniformly mixes a binder with the mixed raw material of pulverized coal and coal to prepare a mixture.

In this exemplary embodiment, in order to ensure the formability of the pulverized coal, the binder may be formed of tar, pitch, syrup or glycerin-based binder.

As shown in FIG. 11, the forming machine 65 has a double-roll type structure. For example, the forming machine 65 may include two rollers 66 arranged opposite to each other and rotated, a funnel 67 arranged on the upper portion of the rollers, and a pressing screw 68 installed in the funnel. There is no particular limitation on the specific structure of the molding machine.

Therefore, the mixture charged from the mixer 64 into the molding machine 65 is press-molded by passing between the twin rolls of the molding machine to manufacture a coal briquette P having a predetermined shape.

Wherein, the mixing and molding of the pulverized coal, coal and binder are carried out at room temperature lower than that of the prior art. That is, the high-temperature pulverized coal is mixed with undried coal and a binder to lower its temperature to 80° C. or lower. Therefore, mixing and molding of pulverized coal can be performed at a lower temperature than in the prior art.

Hereinafter, the pulverized coal briquetting method of the present exemplary embodiment will be explained with reference to the coal briquette manufacturing machine.

The manufacturing method includes mixing a binder with a mixed raw material of pulverized coal classified in a coal drying process and undried coal to prepare a mixture, and molding the prepared mixture to manufacture a coal briquette.

The particle size of the pulverized coal classified in the fluidized bed dryer is 0.3mm or less, the temperature is 80-150°C, and the moisture content is reduced to 3% or less. In an undried state, the moisture content of the coal is 7-10%.

The pulverized coal, coal, and binder supplied to the mixer in a predetermined ratio are uniformly mixed to prepare a mixture.

As described above, by mixing the pulverized coal with undried coal, the temperature of the pulverized coal can be lowered, whereby the pulverized coal can be molded at room temperature compared to the prior art.

The mixture is transferred to a molding machine (ie, the next step process) and compression-molded, thereby manufacturing coal briquettes with a predetermined shape. Wherein, the mixture is in the state of mixing high-temperature pulverized coal and low-temperature coal, and the temperature of the mixture is lowered. Therefore, the process of compressing and molding the mixture is also performed at a lower temperature than the prior art, just like the mixing process.

Wherein, the binder is formed of tar, pitch, syrup or glycerin binder.

In this exemplary embodiment, based on 100 parts by weight of the mixed raw material, the binder may be extrapolated in an amount of 4˜8 parts by weight. In the case where the binder is included in an amount of less than 4 parts by weight, the formability of pulverized coal deteriorates. Also, if the content of the binder exceeds 8 parts by weight, the promoting effect by the binder is no longer expected.

Figure 12 illustrates the experimental results of coal briquette forming ratio versus binder mixing ratio.

The experiment was conducted by using coal briquettes made by mixing pulverized coal classified in a drier, undried coal, and a binder and compression molding with a molding machine. The pulverized coal used to make coal briquettes has a particle size of 0.3mm and a moisture content of 2%. A raw material having a particle size of 3 mm and a moisture content of 9% was used as coal. Among them, based on 100 parts by weight of the mixed raw material having the above-mentioned components, 86% by weight of pulverized coal, and 14% by weight of coal, coal briquettes were prepared by changing the mixing amount of the binder. A glycerin-based binder was used as a binder.

In addition, a mixture of pulverized coal, coal, and a binder was compression-molded using a molding machine (Komarek Briquetter) to produce a coal briquette. At this time, the molding pressure of the molding machine was 1.5 t/cm, the rotation speed of the roll was 3 rpm, and the compression transfer speed of the mixture was 30 rpm.

The test of the molding rate of the manufactured coal briquettes was carried out by confirming the molding rate of the coal briquettes that maintained their shape after passing through the molding machine, and the molding ratio of the moldings that passed through the molding machine with a particle size of 1mm or more of.

As shown in FIG. 12, it can be confirmed that when the content of the binder is 4 parts by weight or more, the molding rate is improved. Also, it can be seen that when the content of the binder is 6 parts by weight or more, the molding ratio of the coal briquette shows 80%, the molding ratio of the molded product shows 85%, and the molding ratio remains constant.

Therefore, it can be seen that similar to the aforementioned experiment, when the binder is mixed in an amount of 4 to 8 parts by weight based on 100 parts by weight of the mixed raw material, the molding rate can be sufficiently ensured.

Meanwhile, in the present exemplary embodiment, the coal may be included in an amount of 10˜40 wt % based on the mixed raw material, and the pulverized coal may be included in an amount of 60˜90 wt % based on the mixed raw material.

When the mixing ratio of coal and the mixed raw material is less than 10% by weight, the amount of pulverized coal is relatively increased to reduce the strength of the coal briquette. Also, when the mixing ratio of coal to the mixed raw material exceeds 40% by weight, it is notable that the strength of the coal briquettes decreases.

Figure 13 illustrates the experimental results of coal briquette strength versus the mixing ratio of pulverized coal and coal.

The experiments were conducted by using coal briquettes made by mixing classified pulverized coal, undried coal and binder in a drier and compression molding with a molding machine. The pulverized coal used to make coal briquettes has a particle size of 0.3mm and a moisture content of 2.7%. A raw material having a particle size of 3 mm and a moisture content of 8.7% was used as coal. A mixed raw material of pulverized coal and coal having the above composition was mixed with a glycerol-based binder in an amount of 6 parts by weight as a binder based on 100 parts by weight of the mixed raw material. Also, a mixture of pulverized coal, coal, and a binder is compressed into a coal briquette using a molding machine (Komarek Briquetter). At this time, the molding pressure of the molding machine was 1.5 t/cm, the rotation speed of the roll was 3 rpm, and the compression transfer speed of the mixture was 30 rpm.

The test of the strength of the manufactured coal briquettes was performed by a compressive strength measuring machine for measuring the strength when the coal briquettes were crushed.

As shown in Figure 13, it can be seen that the compressive strength of coal briquettes increases with the increase of pulverized coal mixing amount. In addition, in the compressive strength test performed after drying the coal briquettes for 5 days, generally, the compressive strength of the coal briquettes increases as the amount of pulverized coal mixed increases.

Experimental results show that when coal is included in an amount of 10% by weight or less, the mixing amount of coal is reduced to an extreme value or less, thereby rapidly reducing the strength of coal briquettes. Also, when the blending amount of coal is 10% or more, the strength remains almost constant, whereas if the blending amount exceeds 40% by weight, a decrease in strength is shown.

Therefore, similarly to the aforementioned experiment, it can be seen that the strength of the coal briquette is sufficiently ensured when the coal blending content is 10 to 40% by weight based on the blended raw material.

As described above, in the drying apparatus of the present invention, coal can be dried efficiently by two fluidized bed dryers, and the classification rate of pulverized coal can be improved. The pulverized coal classified in the fluidized bed dryer is pressed into a coal briquette with sufficient strength by the coal briquette making machine of the device of the present invention. The coal briquettes produced by the coal briquette making machine are loaded into the carbonization chamber of the coke oven together with the dried coal. Therefore, even for low-rank coal, effective drying and briquetting of pulverized coal can be performed by the apparatus of the present invention, thereby increasing the charge density of coal charged into a coke oven. Therefore, the amount of low-rank coal can be innovatively improved.

As above, the exemplary embodiments of the present invention have been illustrated and described, but various changes and other exemplary embodiments may be made by those skilled in the art of benzene. Such changes and other exemplary embodiments are contemplated and covered by the appended claims, which are within the spirit and scope of the invention.

Claims (43)

1., for the device of dry coking charcoal, comprising:

Fluid bed dryer, described fluid bed dryer sprays hot blast to coal and forms fluidized-bed, and carries out drying to coal;

Coal supply section, described coal supply section is connected to described fluid bed dryer with to loading coal in described fluid bed dryer; And

Hot blast feeding part, described hot blast feeding part is connected to described fluid bed dryer to supply hot blast;

Wherein provide at least two fluid bed dryers and it is connected successively, to make coal successively through each fluid bed dryer and by coal drying,

Wherein described at least one, fluid bed dryer also comprises cyclic part, and described cyclic part makes the hot blast by being installed on breaker plate ejection wherein, different with the flow velocity of periphery office at the middle body of breaker plate, to make coal circulate, and

Wherein in described cyclic part, in the lower chamber of breaker plate bottom being formed at fluid bed dryer, be provided with separator tube, described separator tube divides lower chamber, thus supplies hot blast independently to the middle body of described breaker plate and peripheral part,

Described hot blast feeding part comprises central hot air duct and periphery hot air duct, described central hot air duct is connected to described separator tube, and it is inner to breaker plate middle body supply hot blast by separator tube, described periphery hot air duct is connected to described lower chamber, and by separator tube externally to breaker plate peripheral part supply hot blast

Thus, the hot blast of different in flow rate is supplied to described central hot air duct and described periphery hot air duct.

2. the device for dry coking charcoal according to claim 1, wherein,

In fluid bed dryer described at least one, the supplier being fed to coal wherein to hot blast feeding direction toward each other.

3. the device for dry coking charcoal according to claim 2, wherein,

Fluid bed dryer vertical arrangement described at least one is with from top lower portion loading coal.

4. the device for dry coking charcoal according to claim 1, wherein,

The temperature or the flow velocity that are fed to the hot blast in described fluid bed dryer are different from each other for each fluid bed dryer.

5. the device for dry coking charcoal according to any one of claim 1 to 4, wherein,

Described fluid bed dryer, comprising:

First class bed dryer, described first class bed dryer carries out fluidisation with coal is dry and classification to coal;

Second fluid bed dryer, described second fluid bed dryer is connected to first class bed dryer to carry out fluidisation to the coal through first class bed dryer with coal is dry and classification.

6. the device for dry coking charcoal according to claim 5, wherein,

Pipe connecting for mobile coal is installed between the outlet and the entrance of the second fluid bed dryer of described first class bed dryer.

7. the device for dry coking charcoal according to claim 6, wherein,

Described fluid bed dryer comprises: breaker plate, and described breaker plate sprays hot blast;

Lower chamber, described lower chamber is arranged in the bottom of described breaker plate, and is connected with hot blast feeding part, thus imports hot blast; With

King-tower, described king-tower is arranged in moisture-free coal on described breaker plate, and described king-tower side is formed with the outlet of coal that coal flows into entrance wherein and discharge drying.

8. the device for dry coking charcoal according to claim 6, wherein,

Described hot blast feeding part comprises: gas blower, and described gas blower is arranged in the hot air duct of the lower chamber being connected to described fluid bed dryer to supply hot blast;

Well heater, described well heater is arranged on described hot air duct to heat the hot blast supplied; With

Under meter, described under meter is arranged on described hot air duct to control to be supplied to the flow of the hot blast of fluid bed dryer.

9. the device for dry coking charcoal according to claim 1, wherein,

Described cyclic part is arranged on the fluid bed dryer of foremost in the fluid bed dryer connected successively.

10. the device for dry coking charcoal according to claim 1, wherein,

In described cyclic part, the flow velocity being fed to the hot blast of described breaker plate middle body is greater than the flow velocity of the hot blast being fed to peripheral part.

11. devices for dry coking charcoal according to claim 10, wherein,

The flow velocity being fed to the hot blast of described breaker plate middle body is 5 ~ 8 times of the minimum fluidization velocity of coal.

12. devices for dry coking charcoal according to claim 11, wherein,

The flow velocity being fed to the hot blast of described breaker plate peripheral part is 1 ~ 2 times of the minimum fluidization velocity of coal.

13. devices for dry coking charcoal according to claim 1, wherein,

Described cyclic part also comprises cylindrical tube, and described cylindrical tube is installed on the middle body top of breaker plate in described fluid bed dryer with being separated by with breaker plate.

14. devices for dry coking charcoal according to claim 13, wherein,

The size of described cylindrical tube is 1/2 ~ 1/4 of fluid bed dryer internal diameter.

15. devices for dry coking charcoal according to claim 1, wherein,

Described cyclic part also comprises cylindrical tube, and described cylindrical tube is installed on the middle body top of breaker plate in described fluid bed dryer with being separated by with breaker plate, and described separator tube has the size being equivalent to described cylindrical tube.

16. devices for dry coking charcoal according to any one of claim 1 to 4, wherein,

Described hot blast feeding part, comprising: take-off pipe, described take-off pipe be arranged on connect coke oven combustion chamber and flue exhaust emission tube road on to supply the hot blast of waste gas as coal drier; And gas blower, described gas blower is arranged in described take-off pipe to supply waste gas.

17. devices for dry coking charcoal according to claim 16, also comprise:

Dust catching part, described dust catching part to be arranged on described take-off pipe with pack processing containing dust in the offgas.

18. devices for dry coking charcoal according to claim 17, wherein,

Described dust catching part, comprising: at least one cyclonic separator, and described cyclonic separator is arranged on described take-off pipe; Main valve, described main valve is arranged in described discharge line, for opening and closing discharge line, to carry waste gas to described take-off pipe; Root valve, described root valve is arranged in described take-off pipe to open and close take-off pipe.

19. devices for dry coking charcoal according to claim 18, wherein,

Described hot blast feeding part comprises: bypass tube, and described bypass tube is for connecting described discharge line and described gas blower; With

By-pass valve, described by-pass valve is arranged on to open and close bypass tube on described bypass tube,

Thus, waste gas is made selectively through described dust catching part.

20. devices for dry coking charcoal according to any one of claim 1 to 4, also comprise:

Coal briquette maker, described coal briquette maker is connected to described fluid bed dryer so that the fine coal of classification is pressed into block,

Wherein, described coal briquette maker comprises: fine coal funnel, and described fine coal funnel is for being stored in the fine coal of classification in described fluid bed dryer;

Coal hopper, described coal hopper is for storing the coal of undried;

Binding agent funnel, described binding agent funnel is for storing binding agent;

Mixing tank, described mixing tank is connected to described each funnel to mix fine coal, coal and binding agent; With

Forming machine, described forming machine is connected to described mixing tank so that mixture is pressed into coal briquette.

21. devices for dry coking charcoal according to claim 20, comprising:

Fine coal tempering tank, described fine coal tempering tank be connected to described fine coal funnel with by fine coal from fine coal funnel by predetermined proportion discharge and be transplanted on described mixing tank.

22. devices for dry coking charcoal according to claim 20, comprising:

Coal tempering tank, described coal tempering tank be connected to described coal hopper with by coal from coal hopper by predetermined proportion discharge and be transplanted on described mixing tank.

23. devices for dry coking charcoal according to claim 20, comprising:

Binding agent tempering tank, described binding agent tempering tank be connected to described binding agent funnel with by binding agent from binding agent funnel by predetermined proportion discharge and be transplanted on described mixing tank.

24. devices for dry coking charcoal according to claim 20, wherein,

The mixing raw material meter of the fine coal based on 100 % by weight and coal, comprises the coal that content is 10 ~ 40 % by weight.

25. devices for dry coking charcoal according to claim 20, wherein,

Based on the fine coal of 100 weight parts and the mixing raw material meter of coal, comprise the described binding agent that content is 4 ~ 8 weight parts.

26. 1 kinds of methods for dry coking charcoal, by supplying hot blast so that coal fluidisation is by coal dry in fluid bed dryer, described method comprises:

Make coal successively by the fluid bed dryer of multistage connection, thus dry described coal in order,

Wherein different with the flow velocity of the hot blast being fed to breaker plate peripheral part by the flow velocity of the hot blast making to be fed to the breaker plate middle body be installed in fluid bed dryer, carry out circulation and drying to make coal,

Wherein said flow velocity is different to be realized by the cyclic part be included in fluid bed dryer described at least one, and

Wherein in described cyclic part, in the lower chamber of breaker plate bottom being formed at fluid bed dryer, be provided with separator tube, described separator tube divides lower chamber, thus supplies hot blast independently to the middle body of described breaker plate and peripheral part,

Hot blast feeding part comprises central hot air duct and periphery hot air duct, described central hot air duct is connected to described separator tube, and it is inner to breaker plate middle body supply hot blast by separator tube, described periphery hot air duct is connected to described lower chamber, and by separator tube externally to breaker plate peripheral part supply hot blast

Thus, the hot blast of different in flow rate is supplied to described central hot air duct and described periphery hot air duct.

27. methods for dry coking charcoal according to claim 26, comprising:

First drying step, carries out fluidisation with dry to carry out classification to coal by first class bed dryer to coal; And

Second drying step, in the second fluid bed dryer of multiple stage arrangement, carries out fluidisation to the coal of drying in the first drying step and dry to carry out classification to coal.

28. methods for dry coking charcoal according to claim 27, wherein,

In each drying step, the flow velocity being fed to the hot blast of fluid bed dryer is 5 ~ 8 times of minimum fluidization velocity.

29. methods for dry coking charcoal according to claim 27, wherein,

In each drying step, the temperature being fed to the hot blast of fluid bed dryer is 120 ~ 200 DEG C.

30. methods for dry coking charcoal according to claim 27, wherein,

In the first drying step, the supply loading the coal of first class bed dryer is 20kg/h.

31. methods for dry coking charcoal according to claim 27, wherein,

The temperature of the hot blast of described first drying step or flow velocity are different from temperature or the flow velocity of the hot blast of the second drying step.

32. methods for dry coking charcoal according to claim 31, wherein,

The temperature of the hot blast of described first drying step is greater than the temperature of the hot blast of the second drying step relatively.

33. methods for dry coking charcoal according to claim 31, wherein,

The flow velocity of the hot blast of described first drying step is less than the flow velocity of the hot blast of the second drying step relatively.

34. methods for dry coking charcoal according to claim 26, wherein,

The flow velocity being fed to the hot blast of described breaker plate middle body is greater than the flow velocity of the hot blast being fed to peripheral part.

35. methods for dry coking charcoal according to claim 34, wherein,

The flow velocity being fed to the hot blast of described breaker plate middle body is 5 ~ 8 times of the minimum fluidization velocity of coal.

36. methods for dry coking charcoal according to claim 35, wherein,

The flow velocity being fed to the hot blast of described breaker plate peripheral part is 1 ~ 2 times of the minimum fluidization velocity of coal.

37. methods for dry coking charcoal according to any one of claim 26 to 33, wherein,

Using the waste gas of discharging from coke oven combustion chamber as hot blast feeding in described fluid bed dryer, to carry out drying to coal.

38., according to the method for dry coking charcoal according to claim 37, also comprise:

The dust be contained in waste gas is being removed while in described waste gas feed to drying machine.

39. methods for dry coking charcoal according to any one of claim 26 to 33, also comprise:

By the fine coal compression moulding of discharging in coal drying process,

Wherein the shaping of fine coal comprises: prepare mixture by being mixed with binding agent with the mixing raw material of the coal of undried by fine coal; Coal briquette is manufactured with by prepared mixture compression moulding.

40. according to the method for dry coking charcoal according to claim 39, wherein,

The manufacture of described coal briquette is at room temperature carried out.

41. according to the method for dry coking charcoal according to claim 39, wherein,

Described binding agent is be selected from least one in pitch, tar, syrup or glycerols.

42. according to the method for dry coking charcoal according to claim 39, wherein,

Based on mixing raw material meter, comprise the coal that content is 10 ~ 40 % by weight.

43. according to the method for dry coking charcoal according to claim 39, wherein,

Based on the fine coal of 100 weight parts and the mixing raw material meter of coal, comprise the binding agent that content is 4 ~ 8 weight parts.