JPH06210154A - Vertical moving bed and its operation - Google Patents

Abstract

PURPOSE:To treat a gas high in dust concn. in the industrial gas treating moving bed having the gas flow inlet and outlet in the direction orthogonal to the packed bed of a solid granular material by setting the inlet of the solid granular material to the moving bed at a position shifted from the center toward the gas outlet. CONSTITUTION:The inlet 2 for a solid granular material 13 (e.g. sintered ore) is provided at the upper part and a solid granular material discharger 8 at the lower part, and the packed bed of the material is formed between louvers 4 furnished in parallel to the vertical periphery and a wire mesh 5. In this industrial gas treating moving bed having a gas inlet 6 on one side and the outlet 7 on the other side in the direction orthogonal to the packed bed, the inlet 2 of the material 13 to the moving bed is shifted from the center toward the outlet 7. Consequently, the material is effectively classified in particle size when the material is charged, rolled on the charging surface and dropped, clogging is prevented at the gas inlet, and the gas high in dust concn. can be treated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial field in which a large amount of exhaust gas is discharged, for example, a vertical moving bed which is most suitable for purifying a large amount of gas discharged from a sintering furnace, a boiler and the like, and a method of operating the same. .

[0002]

2. Description of the Related Art Exhaust gas generated from, for example, a sintering furnace or a boiler contains a high concentration of dust and impurities. Therefore, if untreated exhaust gas is directly introduced into a moving bed, clogging occurs when the gas passes through. . Therefore, the dust is removed by an electrostatic precipitator or the like before introducing the gas into the moving bed. Alternatively,
It is known to install an auxiliary louver so as to prevent clogging (for example, in Japanese Utility Model Laid-Open No. 53-14).
3173 publication). Further, there is known a moving layer which is less likely to be clogged by dividing the moving layer into two layers and charging coarse particles in the first layer and fine particles in the second layer (for example, Japanese Patent Laid-Open No. 2004-242242). (See Japanese Laid-Open Patent Publication No. 53-136769). These devices have the following features before introducing gas into the moving bed:
Since the dust can be removed by the dust remover, it is an effective means for preventing clogging of the moving bed due to dust and stably operating the moving bed.

[0003]

However, in the conventional device, it is necessary to install a dust collector, which requires a large amount of equipment cost and maintenance and maintenance cost, and is not an economical device. Further, although the structure in which the auxiliary louver is installed is effective in preventing clogging to some extent, there is a limit to the concentration of dust that can be treated. Also,
The moving bed is divided into two layers, and the first layer is charged with coarse particles and the second layer is charged with fine particles. The moving bed is an effective means for preventing clogging, but the structure is complicated and solid particles The transportation route was complicated and the equipment cost was high, which was not economical.

The present invention solves the above-mentioned conventional problems, and provides a vertical moving bed capable of purifying industrial gas containing a high concentration of dust without clogging, and a method of operating the same. With the goal.

[0005]

In order to achieve the above object, the gist of the present invention is as follows. That is, 1. A charging port for the solid particulate matter is provided at the upper part, and a discharge device for the solid particulate matter is provided at the lower part, and a packed layer of the solid particulate matter is formed between a louver and a wire mesh provided parallel to the outer periphery in the vertical direction. , In an industrial gas treatment moving bed having a gas flow inlet from one side and a gas outlet on the other side in the direction orthogonal to the packed bed, the charging port for the solid particulate matter to the moving bed is set to a gas outlet rather than the center. The vertical moving layer is characterized by being installed eccentrically to the side. In the present invention,
It is preferable that the width of the charging port for charging the solid particulate matter from the storage tank above the moving bed to the moving bed is 1/3 or less of the width of the moving bed. 2. A charging port for the solid particulate matter is provided at the upper part, and a discharge device for the solid particulate matter is provided at the lower part, and a packed layer of the solid particulate matter is formed between a louver and a wire mesh provided parallel to the outer periphery in the vertical direction. In the moving bed for industrial gas treatment having a gas flow inlet from one side in the direction orthogonal to the packed bed and a gas outlet on the other side, a particle size classifier for solid particulate matter should be installed just below the charging port. It is a characteristic vertical movement layer. Also, 3. When the solid particulate matter is charged into the moving bed from the upper reservoir of the moving bed through the charging port, the solid is eccentric to the gas discharge side with respect to the center with respect to the gas inlet as viewed in the direction orthogonal to the packed bed of the solid particulate matter. A granular material is charged, a convex surface is formed around the dropping point of the solid granular material on the charging surface, the particle size is classified when the solid granular material rolls and falls on the convex surface, and a gas inlet port is formed. 3. A method for operating a vertical moving bed, characterized in that coarse particles are charged in the bottom part and fine particles are charged in the falling point part. The solid particulate matter is dropped from the charging port to the particle size classifier, and the solid particulate matter rolls down on the classifier.The fine particles fall from the sieve mesh to the charging surface directly below, and the coarse particles roll on the classifier. This is a method of operating a vertical moving bed characterized by dynamically dropping and charging coarse particles near the gas introduction part.

[0006]

The operation of the present invention will be described with reference to FIGS. FIG. 7 shows that the moving bed of the present invention is used and a sinter ore having a particle size of 3 to 8 mm is charged as a solid granular material, and the dust concentration is about 400 mg /
While processing Nm ³ with sintering exhaust gas is a diagram showing experimental results of the pressure loss was measured in the moving layer from the gas inlet portion 4 to the outlet 5. The figure also shows the results measured using a conventional vertical moving layer. In the conventional moving bed, a sharp pressure drop occurs in the gas inlet louver portion 4, whereas in the moving bed of the present invention, the rate of pressure drop in the gas inlet louver 4 can be reduced. As a result, in the conventional moving bed, the gas performance of the moving bed becomes unstable due to the fluidization of the solid particulate matter due to the gas flow at the gas inlet and the formation of a short-circuited flow path for the gas, resulting in high concentration. Although it was impossible to treat the gas containing dust, it is possible to treat the gas containing a high concentration of dust because the force of the gas flow at the gas inlet to the solid particulate matter is alleviated in the moving bed of the present invention. became.

FIG. 8 is a diagram showing the measurement results of the dust collection rate at each part of the moving bed from the gas inlet 4 to the gas outlet 5 of the moving bed. In a conventional moving bed, if dust is trapped in the gas due to the blocking effect of solid particulate matter, the collection efficiency is further increased. There is a circulation in which the dust of the solid particles is collected, the flow velocity of the gas passing through the voids is increased due to the decrease in the porosity of this portion, and the force of pushing the solid particulate matter by the gas is increased, so that the solid particulate matter is fluidized, A gas flow path was created in the layer and the gas flowed in a short circuit, so that the gas purification capacity decreased or became unstable.

In the moving bed of the present invention, the gas inlet portion is filled with coarse solid granular material, and the fine particles are filled in the downstream side when viewed in the gas flow direction, and the finest particles are filled in the center of the moving bed or the gas discharge side thereof. Thereby, it is possible to mitigate the excessively concentrated dust removal rate at the gas inlet portion 4 in the conventional moving bed. As a result, it is possible to make the dust collection load in the direction of the gas flow uniform and obtain a stable gas treatment capacity. According to the experimental results of the present inventors, the excessively concentrated dust collection at the gas inlet portion 4 is mitigated by eccentricizing the packing portion where the finest particles are gathered toward the gas discharge portion side in the center of the moving bed. Yes, and thus a stable gas handling capacity of the moving bed is obtained.

[0009]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is an example of a vertical sectional view of a vertical moving bed for explaining the structural features and operational features of the device of the present invention. In FIG. 1, 1 is a storage tank for solid particulate matter, 2 is a charging port for solid particulate matter, and a valve for cutting out,
Reference numeral 3 denotes a trajectory of the solid particulate matter, 4 is a portion for introducing the gas into the moving layer, specifically a louver, and 5 is a portion for discharging the gas from the moving layer, specifically a wire mesh. 6 is a gas flow to be introduced into the moving layer can body, 7 is a gas flow to be discharged from the moving layer can body, 8 is a discharge device for a solid granular substance, 9 is a cutting device, 9 is a moving layer, 11 is a solid granular form Material loading surface,
12 is the width of the charging port, 13 is the filling state of the solid particulate matter in the moving bed, 14 is the moving direction of the solid particulate matter in the moving bed, and 15 is the charging surface of the solid particulate matter on the gas introduction side. A can contact device, 16 is the position of the apex of the convex charging surface of the solid granular material, that is, the dropping point of the solid granular material on the charging surface, 1
8 indicates the width of the moving layer.

In FIG. 1, the inlet 2 for the solid particulate matter is installed eccentrically on the gas discharge side of the moving bed 9. The solid particulate material is charged into the moving bed from the charging port 2. In the present invention, since the charging inlet width 12 is as thin as ⅓ or less of the width 18 of the moving bed, the charging speed becomes 3 times or more the moving speed of solid particulate matter in the moving bed. Therefore, the charging speed of the solid particulate matter is made higher than the moving speed in the moving bed, so that the solid particulate matter forms the charging surface 11 having an upward convex shape. The solid granular material charged and dropped at the apex 16 of the charging surface having a convex upward rolls and drops along the slope of the convex surface. Of the solid granular materials, coarse particles have a large mass and thus are more likely to roll and fall than fine particles. Therefore, coarse particles gather and are charged in the convex skirt 15, that is, the gas introduction portion 4, and fine particles are present at the falling point portion. Since the particles remain, fine particles can be collected and charged.

FIG. 2 is a vertical sectional view of the transfer layer and the charging surface of the solid particulate material. A conventional moving bed and charging surface are also shown for comparison. The reason why the charging port 2 is installed eccentrically to the gas discharge side 5 with respect to the center of the moving bed will be described with reference to FIG. In FIG. 2, the thick line and the thick dash-dotted line are
1 shows a transfer bed of the present invention and a charging surface for solid particulate matter. The thin line and the thin dash-dotted line indicate the conventional moving bed and the charging surface for solid particulate matter. The moving bed of the present invention in which the charging port is eccentric is compared with the conventional moving bed in which the charging port is located at the center, and the distance 19 in which it rolls and falls even if the peaks of the convex charging surfaces are the same height. A large and sufficient particle size distribution can be obtained.

According to the experiments conducted by the present inventors, if the loading width is 1/3 or less of the moving bed width, a favorable particle size distribution due to rolling fall can be obtained. Since the solid particulate matter moves in the moving layer between the louver 4 and the wire mesh 5 in parallel with the louver and the wire mesh, the state in which the solid particulate material is charged, that is, the coarse particles in the gas introduction part 4 is at the charging drop point. A moving bed, which is filled with fine particles, is formed between the charging surface and the discharge port 8. Since the moving bed having such a packed structure of solid particulate matter is formed, the gas 6 introduced into the moving bed contacts and acts on the solid particulate matter packed bed composed of the coarsest particles in the louver 4 part, and the gas is As it moves in the moving bed in the wire mesh direction 5 which is the gas discharge direction, it gradually comes into contact with and acts on the solid granular material packed bed of fine particles, and is composed of the finest particles below the charging and dropping point of the solid granular material. Contact and act with the packed bed of solid particulate material.

FIG. 3 is another example of the apparatus of the present invention, which is a vertical sectional view of the vertical moving layer for explaining the structural and operational features thereof. In FIG. 3, a classifying device 10 is installed between the solid granular material charging port 2 and the charging surface 11 to classify the solid granular material so that coarse particles near the inlet louver 4 and fine particles at the center or rear of the moving bed are fine. Charged with particles. The classifier 10 is a normal sieve screen shown in FIG. 4 (a) and FIG. 4 (a) viewed from the direction A, and is viewed from direction A in FIG. 5 (a) and FIG. 5 (a) ( b) A grizzly having a diverging opening shape shown in the figure, and a bar material having a diverging opening shape shown in FIG. 6A and FIG. 6A viewed from the direction A in FIG. To use. The classifying device 10 is fixed directly to the moving bed 9 or is fixed to the moving bed body via a supporting member. When the solid granular material has tackiness or has low sieving property, the sieving performance may be improved by vibrating the classifying device with a known oscillating device.

Although the present invention has been described with reference to FIGS. 1 and 3 by taking a moving layer composed of one layer as an example, the apparatus of the present invention can be applied to the case where a moving layer is further installed behind the gas discharge section 5. In such a case, since the rear moving layer has the ability to capture dust in the gas discharged from the moving layer of the present invention, the finest particles are filled in the gas discharging section 5 of the moving layer. This is preferable in terms of distribution of the dust collection rate of all moving layers including the moving layer at the rear.

Examples will be described more specifically below. As a solid granular material, 3 to 8 mm sinter ore was charged into the apparatus of the present invention, and sinter exhaust gas having a dust concentration of about 400 mg / Nm ³ was treated at a gas flow rate of 0.6 m / sec. Example 1 of Table 1 is shown in FIG.
It is an example using the moving bed of the present invention shown in FIG. In Example 2, the bottom of the charging surface is located above the louver 4 and the lower limit is set at a position twice the thickness of the moving layer, and 200 mm above the lower limit.
It is an example in which the upper limit value is set to. Example 3 is an umbrella-shaped grizzly type shown in FIG. 4, which has a trapezoidal opening shape with an upper opening of 5 mm and a lower opening of 10 mm, and has two stages of puddle arrangement and is provided with a vibrating device. The device 10 was installed.
Table 1 shows the measurement results of the pressure difference between the gas inlet and the portion 150 mm behind the gas inlet as the evaluation characteristics of the gas treatment. For comparison, the table shows an example in which gas treatment was performed using the conventional moving bed under the same conditions as in the present invention.

[0016]

[Table 1]

In the conventional moving bed, the pressure difference is about 300 mmAq.
In contrast, in Example 1 of the present invention, the pressure difference is about 25.
In Example 2 of the present invention, the pressure difference in the moving bed was reduced to about 200 mmAq, and in Example 3 to 150 mmAq. Further, in the conventional moving bed, pressure fluctuation was observed with time, whereas in the present invention, the pressure transition was stable in all cases. That is, stable gas treatment capacity was obtained in any of the present inventions.

In the embodiment of the present invention, an example has been described in which the position of the sintering ore charging inlet is eccentrically installed from the gas outlet to the position of 1/4 of the bed width of the moving bed. Not limited to this, the effect of improving the gas processing capacity can be obtained by making the charging port eccentric. Similarly, an example in which the grizzly type is used as the classifying device has been described, but the same effect can be obtained when the wire mesh type classifying device of FIG. 4 and the bar material combination type classifying device of FIG. 6 are used.

[0019]

According to the present invention, when the industrial gas containing a high concentration of dust is treated, the flow of the solid particulate matter and the flow of the gas can be kept stable.
It is possible to treat industrial gas containing high-concentration dust more than twice the dust concentration limit.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an operating situation of a moving bed of the present invention.

FIG. 2 is an explanatory view schematically showing an operating condition of a moving bed charging surface.

FIG. 3 is an explanatory view showing another operation situation of the moving bed of the present invention.

FIG. 4 shows an example of a classifying device, (a) is a sectional view, and (b) is a sectional view.
[Fig. 6] is a view seen from the direction A of (a).

FIG. 5 shows another example of a classification device, (a) is a cross-sectional view,
(B) is the figure seen from the A direction of (a).

FIG. 6 shows another example of a classification device, (a) is a sectional view,
(B) is the figure seen from the A direction of (a).

FIG. 7 is a diagram showing changes in the collection rate of dust to solid particulate matter in the direction from the gas inlet to the outlet of the moving bed.

FIG. 8 is a diagram showing changes in pressure in the direction from the gas inlet to the outlet of the moving bed.

[Explanation of symbols]

1 Reservoir 2 Loading valve 3 Solid particulate matter drop trajectory 4 Gas inlet louver 5 Gas outlet wire mesh 6 Gas inlet flow 7 Gas outlet flow 8 Ejector 9 Moving bed upper can 10 Classifier 11 Solid particulate matter charging surface 12 Width of charging port 13 Solid particulate matter 14 Moving direction of solid particulate matter 15 Contact position between loading surface and moving layer upper can body 16 Drop point of charging surface 17 Moving can body portion opened below moving bed upper part Position of joint between layer and parallel or vertical can body part 18 Layer width of moving layer 19 Rolling drop distance

Claims (4)

[Claims] 1. A solid particulate matter inlet is provided at an upper part, and a discharge device for the solid particulate matter is provided at a lower part, and the solid particulate matter is provided between a louver and a wire mesh provided parallel to a vertical outer periphery. In a moving bed for industrial gas treatment, which forms a packed bed and has a gas flow inlet from one side in the direction orthogonal to this packed bed and a gas discharge opening on the other side, the inlet for the moving bed of solid particulate matter is located at the center. The vertical moving layer is characterized in that it is installed eccentrically to the gas outlet side. 2. A solid particulate matter inlet is provided at an upper portion, and a solid particulate matter discharge device is provided at a lower portion, and the solid particulate matter is provided between a louver and a wire mesh provided parallel to a vertical outer periphery. In a moving bed for industrial gas treatment that forms a packed bed and has a gas flow inlet from one side and a gas outlet on the other side in a direction orthogonal to this packed bed, a particle size classifier for solid particulate matter is installed immediately below the charging port. A vertical moving layer characterized by being formed. 3. A direction in which a dropping point of the solid particulate matter onto the charging surface is orthogonal to the packed bed of the solid particulate matter when the solid particulate matter is charged into the moving bed from the moving bed upper storage tank through the charging port. Looking at the center, the solid particulate matter is charged by being eccentric so as to be closer to the exhaust gas side than the center, and a convex surface centering on the dropping point of the solid particulate matter is formed on the charging surface. The method for operating a vertical moving bed is characterized in that the particles are classified when rolling and falling, and coarse particles are charged in the gas inlet and fine particles are charged in the falling point. 4. A solid particulate material is dropped from a charging port to a particle size classifying device directly below the charging port and is rolled on the classifying device, fine particles drop from a sieve mesh to a charging surface directly below, and coarse particles are classified. A method for operating a vertical moving bed, characterized by rolling and dropping on the equipment and charging coarse particles near the gas introduction part.