KR100906997B1 - Fluidized bed scrubber using porous media for gas purification - Google Patents

Abstract

The present invention reduces the pressure loss and improves the cleaning effect by increasing the mixing effect by flowing a porous media-type fluidized bed made of a polymer material at a certain place in the scrubber using a flow of gas and a cleaning liquid. A three-phase fluidized bed scrubber that reduces clogging in all devices. Fluidized bed scrubbers have a larger contact surface area than comparable packed bed or plate scrubbers, so smaller installations can effectively achieve their goals. The effects of gas flow and liquid increase due to the flow of the filling, and the self-cleaning action of the particles deposited on the surface of the filling and eventually blockage can be obtained. Porous media applied as a filler can control the pore size and specific gravity at the time of manufacture to maintain the optimum fluidization conditions required in the scrubber and to remove gas and particles accompanying the gas at the same time.

Porous media, fluidized bed scrubbers, gas distributors, scrubbers

Description

Fluidized bed scrubber using porous media for gas purification}

The present invention relates to a fluidized bed scrubber used for gas purification, and more particularly to a polymer instead of a conventional scrubber, which is fixed or plate-mounted with plastic, glass, and marble fillers to remove gaseous and / or particulate matter in the gas. It relates to a scrubber for flowing the porous media of the material.

Scrubbers are the most common atmospheric facility that has been used for decades to purify gas. The liquid is sprayed from above and the pollutant gas is blown down to absorb and remove the gaseous substances dissolved in the liquid, and the particulate matter collides with the fine droplets to be cleaned. Therefore, the longer the gas and liquid droplets meet, the greater the amount of absorption or collision of substances in the gas and the greater the purification efficiency. Therefore, objects with large specific surface area (surface per unit volume), called fillers, in various ways Used as For example, a packed bed scrubber with a packing material fixed inside the scrubber and gas and liquid contacting the surface of the scrubber is simple to manufacture and operate, while the height of the packed bed is high and the internal flow velocity is low (typically 1.0 m / sec ~ 2.0m / sec) maintains a constant purification efficiency with sufficient contact time between gas and droplets, increasing the size of the equipment, and rapidly increasing the pressure loss when treating gaseous materials at high internal flow rates (usually more than 3.0m / sec). Alternatively, there is a drawback (breakthrough point) that occurs at a moment, so that a certain amount of gas cannot be processed, and particulate matter accumulates in the packed layer, which causes frequent blockages, and it is difficult to remove particulate matter of 3 μm or less. In order to alleviate the blockage and remove particulate matter, a fluidized bed scrubber using glass beads or PP ball has been developed. However, due to the lower specific surface area of the fluid in gaseous materials, it is less effective than a packed bed scrubber, making it difficult to commercialize. There were many points.

Therefore, there is a need for a high-efficiency fluidized bed scrubber using a new concept of packing having a large specific surface area, low pressure loss, and a specific gravity suitable for fluidization. In particular, industries that manufacture semiconductors and LCDs use solvents or chemicals that are highly acidic and toxic, unlike general manufacturing, so the emission allowance is very low, and white smoke is often generated due to particle discharge. There is a need for a highly efficient scrubber capable of processing not only materials but also particulate matter at the same time.

It is an object of the present invention to overcome the disadvantages of various types of scrubbers currently used, and to develop a fluidized bed scrubber having high purification efficiency and good operating conditions such as packing materials, both in gaseous and particulate matter. More specifically, when the packing material flows, the scale deposited on the surface should have a structure that is easy to detach due to the self-cleaning action, so there should be little blockage and maintain a high purification efficiency even at a high internal flow rate (more than 3.0m / sec). It should have a structure that minimizes the size of the overall system. In addition, the present invention is to provide a high efficiency fluidized bed scrubber with a wider operating range and improved removal efficiency than the conventional fluidized bed scrubber.

In order to achieve the above object, the fluidized bed scrubber according to the present invention is characterized by using a porous medium made of a polymer material as a fluid to purify a gas containing gaseous or particulate matter.

   Preferably, the plurality of porous media are each made of a foamed polymer, polyurethane, polyethylene, polypropylene, vinyl chloride resin, polystyrene, ABS resin, polyvinyl alcohol material, sponge, foam, non-woven structure range of porosity It is in the form of cube or sphere with 5 ~ 100 PPI, length and diameter of 0.4 ~ 6.5cm, and specific gravity containing water is 0.5 ~ 1.2. Or porous media formed by a method other than foaming to increase the porosity in polymer materials. It is in the form of cube or sphere with the length and diameter of 0.4 ~ 6.5cm, respectively, and the porosity is 30 ~ 95%. Is 0.5 to 1.2. More preferably, the plurality of porous media are prepared by coating or adhering or mixing the powder activated carbon and ion exchange resin of 100 to 200 mesh, respectively, on the surface thereof.

The fluidized bed scrubber according to the present invention has a wider contact surface area than a packed bed or plate-shaped scrubber of the same capacity, and thus has a high purification efficiency even at a fast internal passage velocity (more than 3.0 m / sec), so that even a smaller scale facility Effectively achieve the purpose. In addition, the mixing effect between the gas and the liquid is increased by the flow of the filler having a low specific gravity, and the filling is collided with each other while the filler flows without stopping, so that it is also possible to obtain a self-cleaning effect of desorbing particles that are deposited on the surface and eventually cause clogging. have. In particular, the porous media applied as a filler can control the pore size and specific gravity during manufacture to maintain the optimum fluidization conditions required for the scrubber, and the existing fluid made of plastics or glass materials such as PP Ball by using porous media The wider gas contact area has high removal efficiency of gaseous and particulate matter. In the present invention, since the cleaning water is supplied through the OPEN HOLE, the conventional wet scrubber does not supply sufficient washing water due to the clogging of the nozzle by using the spray nozzle, thereby reducing the processing efficiency of gas and particulate matter. Prevented.

Hereinafter, a fluidized bed scrubber device according to an embodiment of the present invention will be described in detail with reference to the accompanying example drawings.

   The present invention overcomes the drawbacks of various types of scrubbers currently in use, and has an object to provide a fluidized bed scrubber device having high purification efficiency and good operating conditions such as packing materials in both gas phase and particulate matter.

   1 is an overall configuration diagram of a fluidized bed scrubber apparatus according to an embodiment of the present invention. FIG. 2 is an enlarged schematic view of a fluidized bed having a porous media shown in FIG. 1, a gas distributor, and first and second mesh networks.

   Fluidized bed scrubber device according to an embodiment of the present invention is a gas inlet (1), cleaning tube (2), droplet removal unit (3), fluidized bed (4), gas distributor 41, the first mesh network 42, and The second mesh net 44 is included.

   The gas introduction part 1 flows upward into the container with harmful gas to be purified.

   The fluidized bed 4 absorbs and removes gaseous substances contained in the exhaust gas, cleans particulate matter, and deposits on the surface by mutually contacting the exhaust gas and the washing water while freely moving the internal space by the pressure of the exhaust gas. It is filled with a plurality of porous media 43 having a structure that detaches the scale by self-cleaning action.

   The plurality of porous media 43 are preferably manufactured by foaming a polymer material or molding a high porosity. The plurality of porous media should be easy to manufacture to have a specific gravity and surface area suitable for abrasion and fluidization, and the scale deposited on the surface during flow should have a structure that is easy to detach by self-cleaning action.

   The washing tube 2 absorbs and removes the gaseous substance contained in the exhaust gas to the fluidized bed 4 and supplies the washing water dispersed downward to wash the particulate matter. Conventional nebulizers or spray nozzles have been used to make the washing water into small droplets to increase the contact area with the gas or particulate matter and to supply the washing water evenly to the entire surface of the filling. The clogging of the nozzle frequently occurs, and a certain amount of washing water is not supplied, thereby degrading gas or particulate matter removal efficiency. In the present invention, clogging does not occur because the cleaning water is supplied through the cleaning pipe (OPEN HOLE) without using a spray nozzle in order to improve this problem.

   The droplet removing unit 3 removes fine water droplets contained in the exhaust gas passing through the fluidized bed 4. The gas discharge part 5 discharges the purified gas which has passed through the droplet removal part 3.

   The gas distributor 41 is installed adjacent to the lower portion of the fluidized bed 4 to support the fluidized bed 43 and to allow the porous media 43 as a filler to flow smoothly, through which the harmful gas passes. have. The gas distributor 41 should not only cause the support of the filling and smoothly maintain the distribution and fluidization of the gas, but also have a form that does not cause excessive pressure loss. In order to smoothly flow the filling material in the fluidized bed scrubber, a gas distributor 41 is installed at the lower part of the filling material. The gas passing area in the gas distribution machine is suitable for 30 to 60% of the total cross-sectional area, and the size of the hole is 40 to 60 times the size of the filling material. % Is preferred. However, if a mesh network of about 40-60% of the filler size is installed on the gas distributor, the size of the gas distributor holes does not need to be considered.

   The first mesh network 42 is located between the fluidized bed 4 and the gas distributor 41. The second mesh net 44 is located at the top of the fluidized bed 4 BOX. The first mesh net 42 and the second mesh net 44 should have a low pressure loss and not easily clogged. The first mesh network 42 is installed to prevent the porous media 43, which is a filler, from being lost through the gas distributor 41 together with the washing water, and forms a washing water film together with the gas distributor to form gaseous and particulate matter. The second mesh net 44 prevents the porous media 43, which is a filler, from leaving the fluidized bed 4 together with the gas by a high flow rate, and forms a washing water film to treat gaseous and particulate matter. To install.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention, and it will be apparent to those skilled in the art that the scope of the present invention is not limited to these examples according to the gist of the present invention.

Example  1: Comparative Experiment of Hydrogen Chloride Removal Efficiency by Type of Filler

   As shown in Table 1, the hydrogen chloride removal efficiencies of the fillers were compared. The experiment was carried out by replacing only the internal filling under the same experimental apparatus and conditions. The random packing of A company used 1 “and the pressure rapidly increased above 2.5m / sec of the flow rate, and the pressure dropped rapidly. It was difficult to maintain the constant flow rate, so the experiment could not be performed at the high flow rate. In case of company A random packing, the removal efficiency decreased as the flow rate increased. Thus, the removal efficiency of hydrogen chloride was 85% at 2.5m / sec. On the other hand, in the fluidized bed scrubber using porous media, as shown in Table 1, the flow of the filling was active even at the passage flow rate of 2 ~ 5m / sec, and showed a hydrogen chloride removal efficiency of more than 98%. Table 1 shows the results of comparing the hydrogen chloride removal efficiency according to the type of filler. In the case of the fluidized bed using PP-Ball, the flow rate of the PP-BALL was not smooth at the flow rate of 3.0 m / sec or less, and the removal efficiency of the gaseous substance was about 80% at the flow rate of 3 to 4 m / sec. It was about 20% lower than the fluidized bed scrubber using.

division RANDOM PACKING 1 " Fluid Bed PP-BALL Fluidized bed porosity material Polypropylene (P.P)  Polypropylene (P.P)  Hydrophilic Polyurethane Fill amount (W × L × H), mm 237 × 237 × 400 237 × 237 × 150 237 × 237 × 100 Size (mm) Φ25.4 Φ20 20 × 20 × 20

Passing flow rate (m / sec) Liquid pH RANDOM PACKING 1 " Fluid Bed PP-BALL Fluidized bed porosity IN OUT efficiency IN OUT efficiency IN OUT efficiency 1.0 2.98 10.5 50.24 2.75 94.53% 1.5 1.98 10.5 47.34 3.09 93.47% 2.0 1.49 10.5 43.84 3.58 91.83% 60.36 1.15 98.09% 2.5 1.19 10.5 38.96 5.82 85.06% 40.22 0.71 98.23% 3.0 0.99 10.5 45.24 7.75 82.87% 37.85 0.56 98.52% 3.5 0.85 10.5 43.15 8.05 81.34% 35.21 0.45 98.72% 4.0 0.74 10.5 38.75 8.25 78.71% 33.36 0.51 98.47% 5.0 0.59 10.5 40.53 0.49 98.79%

Example  2: filling Blockage  Comparative experiment

In order to observe the blockage phenomenon during continuous operation, the change in pressure loss was measured for each type of packing under conditions of high particle inflow. The experiment was carried out by replacing only the internal filling in the same experimental apparatus. The specific experimental conditions and results are shown in Table 2 and Figure 1, respectively. The pressure loss during continuous operation was 128.7 mmAq after 31 days at 38.5 mmAq after installation of T-1 and 123.8 mmAq after 51 days at 18.7 mmAq after installation of T-1, whereas fluidized bed using porous media was 61.5 after installation. After 61 days in mmAq, there was almost no change to 70.3 mmAq. This result shows that there is no blockage compared to the other two charges. Table 2 shows the experimental conditions of the clogging phenomenon of the filling. Figure 3 is a graph showing the pressure loss change according to the type of filler when treating the particles according to the present invention.

division Filling layer (T-1) Filling layer (T-2.3) Fluidized bed (F) Fill amount (mm) (W × H × L) 237 × 237 × 400 237 × 237 × 400 237 × 237 × 150 Size (mm) Φ25.4 Φ58.4 20 × 20 × 20 Inflow (CMM) 6.74 6.74 10.11 Flow rate (m / sec) 2.0 2.0 3.0 Liquid ratio (ℓ / ㎥) 2.97 2.97 1.48

Fluidized bed scrubber according to an embodiment of the present invention can be applied to the field of gas purification.

1 is a view showing a fluidized bed scrubber according to an embodiment of the present invention.

FIG. 2 is an enlarged view of the fluidized bed shown in FIG. 1.

Figure 3 is a graph showing the pressure loss change according to the type of filler when treating the particles according to the present invention.

              <Description of Symbols for Main Parts of Drawings>

1: gas introduction part 2: cleaning tube

3: droplet removal unit 4: fluidized bed

41 gas distributor 42 first mesh net

43: porous media 44: second mesh net

Claims (7)

Fluidized bed porous media made of polymer material to purify gas containing gaseous or particulate matter; And A fluidized bed scrubber comprising a gas distributor through which harmful gas passes to support and smoothly flow the fluidized bed porous media. The method of claim 1, wherein the porous media is a polyurethane, polyethylene, polypropylene, vinyl chloride resin, polystyrene, ABS resin, polyvinyl alcohol foamed sponge, foam, non-woven structure porosity range of 5 to 100 PPI, Han Fluidized bed scrubber in the form of a cube or sphere with sides or diameters of 0.4 to 6.5 cm, respectively, with a specific gravity of 0.5 to 1.2 containing water. The method of claim 1, wherein the porous media is formed of a polymer material by a method other than foaming so as to increase the porosity, the length and diameter of one side is 0.4 to 6.5cm in the form of a cube or sphere, the porosity is 30 to 95% Fluidized bed scrubber having a specific gravity of 0.5 to 1.2. The fluidized bed scrubber according to claim 1, wherein the porous media contains 100 to 200 mesh of powdered activated carbon or ion exchange resin. The fluidized bed scrubber according to claim 1, wherein the gas distributor is installed at a lower portion of the porous media by cutting through 30 to 60% of the cross-sectional area of the layer with a pore size of 40 to 60 percent of the size of the porous media. 5. The fluidized bed scrubber of claim 4, further comprising a first mesh network disposed between the porous media and the gas distributor to form a washing water film at a high flow rate to treat gaseous and particulate matter. 5. The method of claim 4, wherein the porous media and the cleaning tube (OPEN HOLE) or between the cleaning tube and the droplet removing unit to prevent the porous media out of the system by a high flow rate and to form a washing water film to form a gas phase and particulate A fluidized bed scrubber further comprising a second mesh net for treating the material.

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