JPH0125623B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an exhaust gas purification device, and is applicable to chemical factories, metal smelting factories, asphalt plants, new ceramic plants, etc. where harmful odor gases, mist and dust are generated in a mixed manner. It can be used for air conditioning and pollution prevention at various industrial sites such as food, pharmaceutical factories, and electronic component factories. Conventional Technology Conventionally, in order to purify exhaust gas, only a cleaning device using various gas-liquid contact fillers has been installed to prevent pollution by targeting harmful gases. It is known that this method can remove not only harmful gases but also a certain amount of dust. However, since dust is collected only through gas-liquid contact, it is completely impossible for exhaust gas cleaning equipment to remove particles smaller than 1μ, and a large amount of mist is released into the exhaust gas due to gas-liquid contact. However, in order to remove such particles, a conventional large and expensive electrostatic precipitator is installed separately. Problems to be Solved by the Invention Installing an exhaust gas scrubbing tower and an electrostatic precipitator separately for purifying exhaust gas, which is a source of pollution, is wasteful in terms of space and cost. The present invention aims to eliminate such waste by integrating the exhaust gas scrubbing tower and the electrostatic precipitator into an integrated structure. A special public service proposed for this purpose in 1972-
There is an exhaust gas purification device No. 29585. This is an upright purification device through which gas flows, with a flat plate electrostatic precipitator installed at the top and a gas cleaning unit at the bottom.
Because it is a flat plate type electrostatic precipitator, the electrostatic agglomeration effect of the electrostatic precipitator is insufficient due to the generation of spark discharge due to uneven electric field strength due to water droplets. If dust electrodes are used, it is necessary to space the dust collecting electrodes at least 40 cm apart, which increases the size of the device. Means for Solving the Problems In view of these points, the present invention provides a wet electrostatic precipitator in the upper part of an upright purification device and a gas cleaning part in the lower part, and the wet electrostatic precipitator has a non-flat plate shape. By arranging conductive pipes in parallel to form a sag-like dust collection electrode and installing them alternately at an angle, this works in conjunction with the action of a discharge electrode with a large number of needle-like pieces planted in the same direction. As a result, compared to the device with a built-in flat plate type dust collecting electrode, there is no drop in operating voltage due to cleaning spray or performance degradation due to sparks, and it is also possible to use two types of cleaning liquid (water and chemical) at the same time. Therefore, a compact and inexpensive exhaust gas purification device with high voltage, high current density, and high efficiency is provided. Function The present invention forms fine particles of 10μ or less, which are said to be impossible to remove in a normal washing tower, into a sagging shape, and has an inclined dust collection electrode and a large number of needle-like pieces planted in the same direction. A discharge electrode is built into the upper part of the scrubbing tower to remove it, and as a result, it is particularly effective in treating white smoke and mist caused by ultrafine particles of 1 μm or less, which are often found in conventional exhaust gas scrubbing equipment. In addition, in order to easily separate the mist adhering to the sagging dust collecting electrode to the outer cover of this device, and to suppress the occurrence of spark discharge due to uneven electric field strength due to water droplets, the electrode is tilted at an angle of 5 degrees or more with respect to the gas flow direction. A sagging dust collection electrode is installed. Embodiment FIG. 1 shows a first embodiment of the present invention, in which a perforated plate 2 is built into the lower part of the main body 1 of an upright purifier, a lower cleaning spray 3 is attached to the upper part, and gas is introduced from the gas inlet 4. After removing the harmful odor gas, a hollow metal rod or conductive plastic pipe is placed above it in a sagging shape with respect to the gas flow direction.
Dust collection pole 5 installed with an inclination angle of
and a discharge electrode 6 in which a large number of needle-shaped pieces are implanted in the same direction on a metal rod or conductive plastic rod with a cylindrical cross section, and an upper cleaning spray 7 is provided above. 9 is a high-voltage power supply, and 9 is a drain port. Note that the one shown in figure D is the discharge electrode 6.
In this modification, the needle-like pieces are installed in a direction parallel to the gas flow. FIG. 2 shows a second embodiment of the present invention, which differs from the first embodiment in that a filler 10 is built in instead of the perforated plate. In addition, C shows a few examples of the shape of the packing 10, and various other shapes can be used, but those shown in B and C have a collection surface with a specific surface area of 75 m ² /m ³ or more. It has the following. Figure 3 shows various shapes of discharge electrodes, A is a round wire,
B is a star-shaped wire, C is a square wire, D is a square twisted wire, E is a barbed wire, H is a round bar protrusion type, and G is an angled protrusion type. A round bar protrusion type is used. Fig. 4 shows the shapes of various dust collecting electrodes, A is a rod curtain type, B is a pocket type, C is a fin plate type, D is a zigzag type, E is a sagging type in the embodiment of the present invention, and F is a fin plate. Types U and G are square wave type, Chi is groove type, Li is double plate type, and Nu is eggplant type. Effects of the Invention According to the present invention, since the collecting electrode arranged in a sagging shape is parallel to the gas flow and inclined at an angle of 5 degrees or more with respect to the horizontal direction, the cleaning liquid can be collected on the side wall without falling directly below. In addition to being able to use different cleaning solutions (water and chemical solutions) at the same time, which doubles the cleaning capacity, this combination with the action of the discharge electrode, which has many needle-like pieces planted in the same direction, makes it possible to use different types of cleaning solutions (water and chemical solutions) at the same time. Compared to devices with built-in dust electrodes, significantly higher voltages, higher current densities, and higher efficiency are possible. An example of the effects of the exhaust gas purification device according to the present invention is as follows. Inlet exhaust gas concentration 288PPM Inlet dust concentration 105mg/Nm ^3Outlet exhaust gas concentration 7PPM Outlet dust concentration 4mg/Nm ^3Exhaust gas removal rate 97.5% Dust removal rate 96.2% The size savings by the present invention are as follows. Design condition treatment Air volume 9000Nm ³ /H Inlet exhaust gas concentration 270PPM Inlet dust concentration 55mg/Nm ³ outlet exhaust gas concentration 10PPM Outlet dust concentration 5mg/Nm ³ [Table]

[Brief explanation of drawings]

Figures 1A, B, C, and D are a front sectional view, a side sectional view, a plan view of the main part, and a modified example of the main part, showing a first example of implementing the present invention, and Figures 2A, B, C, and D are the main parts of the present invention. A front sectional view, a side sectional view, a perspective view of the main part, and a modification of the main part showing a second example of carrying out the invention, FIG. 3 is an explanatory diagram of various discharge electrodes, and FIG. 4 is an explanatory diagram of various dust collection electrodes. . The symbols in the drawings indicate the following members, respectively. 1... Main body, 2... Perforated plate, 3... Lower part cleaning spray, 4...
Gas inlet, 5... Dust collection electrode, 6... Discharge electrode, 7... Upper cleaning spray, 8... High voltage power supply, 9... Drain port,
10...Filling.

Claims (1)

[Claims] 1. A perforated plate or cleaning filler is built into the lower part of the rigid body that guides the exhaust gas from below to the upper side, a cleaning spray is attached to the upper part, and a hollow metal rod or conductive material is attached to the upper part of the solid body. A collector electrode made of a conductive plastic pipe installed in a sagging manner with respect to the gas flow direction, and a discharge electrode made of a metal material or a conductive plastic material opposed to the collector electrode are arranged, and a cleaning spray is attached to the upper part of the collector electrode. , the discharge electrode is a metal rod or a conductive plastic rod with a cylindrical cross section and a large number of needle-like pieces planted in the same direction, and the collector electrode arranged in a sagging shape is parallel to the gas flow and horizontal. An exhaust gas purification device characterized by being inclined at an angle of 5 degrees or more with respect to a direction. 2 Claims characterized in that the distance between the dust collection electrodes is 40 cm or less, and the dust collection area in the same volume can be more than twice as large as that of a conventional wet electrostatic precipitator. The exhaust gas purification device according to item 1.