JPH0541785Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a dust discharge device for an electrostatic precipitator used in steel manufacturing, cement, waste incineration equipment, etc.

[Prior Art] Conventional dust discharge devices for electrostatic precipitators include a pyramidal hopper type, a ship bottom hopper type, a flat bottom hopper type, and the like. Generally, to scrape up dust, the pyramidal hopper method uses gravity to discharge the dust, so no special ejecting device is required, but the bottom hopper method uses a screw conveyor, and the flat-bottom hopper method uses a scraper conveyor, a chain conveyor, or a reciprocating linear motion. A configuration that combines a mechanism, etc. and a screw conveyor is required.

Figure 4 is a schematic diagram of the pyramidal hopper system.Generally, electrostatic precipitators often have a rectangular shape due to their structure, and the dust collected by the electrodes is brushed off and falls to the discharge device below, so the discharge device is designed with four shapes. A method that uses a pyramid is also often seen.

On the other hand, various improvements have been made to the flat-bottom hopper system because it is necessary to discharge the dust that accumulates on the wide bottom surface without leaving any residue behind. Figures 5 and 6 show a flat bottom hopper system in which rotary rakes 2b, 2c are provided at the center of the bottom surface, and the dust on the surface is scraped up and discharged from one end by the rotation of scraping plates 3b, 3c. In both cases, the surrounding inner wall is made into a sloped surface 15 so that the dust that accumulates in the surrounding area where the scraping board cannot reach will slide down obliquely and be included in the locus of the tip of the board.

In addition, as a special structure for mechanical ejection, as shown in FIG. 7 of Japanese Patent Application Laid-Open No. 60-44067, a rectangular frame 101 is provided which can be slid left and right on the bottom surface by a guide beam 100. In some cases, the main flapper 102, which is loaded and rotatably pivoted at the front and rear of the framework, hangs down alternately and travels while scraping up powder on the bottom surface.

Furthermore, in the case of JP-A No. 62-221457/FIG. 8, a dust scraping body 103 is scraped into the central recess by a sprocket 104 and a chain link 5 at the gate between the electrode and the bottom of the electrostatic precipitator. A configuration is presented in which the screws are dropped and discharged to the outside of the machine using the screw conveyor 106.

[Problems to be solved by the invention] Among the above-mentioned conventional technologies, the first pyramidal hopper method has the advantage of not requiring a special ejection device;
In order to smooth the fall and accumulation of dust that tends to adhere during power outages, the inner wall has a large slope, which reduces the overall height.
A hopper 9a with a large Ha is required, and in high-temperature wet gas processing, the temperature at the lower part of the hopper, which is remote from the electrostatic precipitator, decreases, causing problems such as condensation and corrosion of the hopper and discharge valve.

From this point of view, the flat bottom hopper method is preferable, but it consists of a combination of a scraper conveyor, a chain conveyor, or a reciprocating linear motion mechanism and a screw conveyor, and the device is complicated and there is a lot of sliding between the component parts in the dust. The problem of troubles caused by abrasion of members due to contact with moving parts was unavoidable.

In addition, as shown in Figures 5 and 6, the configuration in which dust is scraped up without the help of other driving members and is intended to dispose of dust in blind areas outside the range, ends up using the pyramidal hopper method described above for the four corners. Similarly, complete evacuation is difficult unless the slope of the inner wall is increased, and therefore the overall heights Hb and Hc must be increased, which results in the loss of the advantage of the flat-bottom hopper method. Furthermore, since the entire inner periphery is formed of an inclined surface, the manufacturing process becomes complicated, which also reduces the advantage of the flat-bottomed hopper method.

In order to solve the above-mentioned problems, the present invention aims to provide a new dust discharge device for an electrostatic precipitator that uses a flat-bottomed hopper type and can discharge dust from all four corners only by driving a rotary rake.

[Means for Solving the Problems] The dust discharge device of the electrostatic precipitator according to the present invention has four corners of the bottom surface that are out of the locus of the tip of the scraping plate of the rotary rake, which are formed one step higher than the bottom surface, and sub-rakes are installed in each of the stepped surfaces. The above-mentioned problem was solved by attaching a auxiliary rake scraping plate and allowing the tips of the auxiliary rake scraping plates to rotate freely in response to impact from the rotating rake scraping plate tips.

[Function] The dust brushed off from the electrostatic precipitator body is deposited on the rectangular bottom surface of the flat-bottom hopper, and as the rotating rake rotates, multiple scraping plates scrape the dust outward from the center of rotation. It is discharged from the outlet near the outer circumference of the rake. Dust accumulated on the triangular surface at a position higher than the bottom of the four corners where the rake plate of the rotary rake cannot reach is removed by a rotatable sub rake consisting of multiple scraper blades installed on the triangular surface. It rotates around the axis by a predetermined angle in response to the impact from the scraping board,
Let the dust fall into the rotating plane of the main rake. The fallen dust is discharged from the outlet by the main rake.

[Example] An explanation will be given based on the drawings. 1 to 3 show the dust discharge device of the present invention.

A rotary rake 2 having a rotating shaft at the center of the bottom surface of a rectangular hopper 1 is rotated by a driver 6, and has a conical cap 21 and a scraping plate 22 in the center, and scraping plates 3A, 3B, 3C, 3D,
It consists of 3E. The dust that has fallen and accumulated on the bottom of the hopper 1 is removed by the scraping plate 22 by the rotation of the rotary rake 2.
The accumulated dust is sent to the next scraping plate 3A, then sequentially sent from 3A to 3B, and then dropped and discharged outside from the discharge port 12 by the scraping plate 3E.

At the four corners of the rectangular hopper 1, there are a plurality of scraping plate blades 5 on a triangular surface 11 which is arranged close to the circular shape and is one step higher than the bottom surface to remove dust by the rotation of the rotary rake 2.
1 and a shaft 52 are provided.
The sub-rake 5 is rotatable and its scraping plate blade 51
extends from the triangular surface toward the center of the rotating rake 2, and the rotating surface of the sub rake 5 and the rotating surface of the rotating rake 2 partially overlap. Therefore, the pin 4 protruding from the end of the rotary rake 2 moves in a circular motion, and the scraper blade 51
In order to impact and move together, the scraper blade 51 rotates by a predetermined angle. That is, the auxiliary rakes 5 at the four corners rotate in increments every time the pin 4 attached to the rotating rake 2 passes, scraping out the dust accumulated on the triangular surface 11 and causing it to fall into the rotating surface of the rotating rake 2. When only the rotary rake 2 is rotated by the drive machine 6 in this manner, most of the dust that has fallen into the hopper 1 is discharged from the discharge port 12.

The flat-bottom rectangular hopper 1 equipped with the rotary rake 2 and the auxiliary rake 5 can have a low overall height H.
Therefore, the overall height when the rectangular hopper 1 is connected to the electrostatic precipitator main body 7 in FIG. 3 can be reduced, so the structure shown in FIGS. Solved the problems of conventional technology.

[Effects of the invention] The present invention has a flat-bottomed rectangular hopper with a main rake and a sub rake driven by the main rake located at a higher position than the main rake. It also has the effect of discharging dust from the four corners inside. Furthermore, the height of the hopper can be lowered to reduce the temperature difference between it and the electrostatic precipitator itself, preventing dew condensation and corrosion inside the hopper.Furthermore, the overall height of the electrostatic precipitator can be lowered, reducing production and installation costs. It has the effect of reducing Since there are no members that slide in the dust in the hopper, there is no sliding wear and maintenance and inspection costs can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a top view of the dust discharge device of the electrostatic precipitator of the present invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig.
Figure 4 is an overall view of the electrostatic precipitator of the present invention, Figure 4 is an overall view of a conventional electrostatic precipitator, Figures 5 and 6 are perspective views of a conventional dust discharge device, Figure 7 is a perspective view showing a conventional technique, FIG. 8 is a vertical sectional view showing another prior art. 1... Flat bottom hopper, 2... Rotating rake, 3...
Scraping board, 5... Sub rake, 11... Step surface,
51...Scraping board wing, H...Total height of hoppa.

Claims (1)

[Scope of utility model registration request] In a dust discharge device for an electrostatic precipitator that has a rotating rake at the center of the bottom of a rectangular flat-bottomed hopper, the four corners of the bottom that deviate from the locus of the tip of the scraping plate of the rotating rake are formed one step higher than the bottom surface, and a sub rake is installed on each of the stepped surfaces. A dust discharge device for an electrostatic precipitator, wherein the tip of the sub-rake scraping plate blade is rotatable in response to impact from the tip of the rotating rake scraping plate.