KR101833390B1 - Rolling Screen Filter System Using Superheated Steam for Removing Fine Particles In Flue Gas Handling Sequence of Thermal Power Plant - Google Patents

Abstract

The present invention relates to a circulation filtering system using superheated steam to remove fine dust in a combustion gas processing process of a thermal power plant. According to an embodiment of the present invention, the circulation filtering system using the superheated steam to remove the fine dust in the combustion gas processing process of the thermal power plant comprises: a housing; a motor; a power transmitting member; a pair of driving sprockets; a pair of driven sprockets; a chain; a screen filter; a first steam pipe; and a second steam pipe. The circulation filtering system using the superheated steam to remove the fine dust in the combustion gas processing process of the thermal power plant of the present invention can increase dust collection efficiency.

Description

TECHNICAL FIELD The present invention relates to a circulating filtering system using superheated steam for removing fine dust in a combustion gas processing process of a thermal power plant,

The present invention relates to a system for collecting a combustion gas generated in a boiler of a thermal power plant in a circulation filter using superheated steam and removing fine dust.

Generally, a boiler is a device which generates water or hot water by heating steam or hot water by a firearm, a combustion gas, other hot gas or electricity to generate water or hot water. In addition to the main body, the boiler consists of combustion devices, combustion chambers, superheaters, vacuum cleaners, air preheaters, ventilation devices, auxiliary devices, automatic controls and other safety valves. The boiler is divided into a steam boiler for generating steam and a hot water boiler for making hot water. In addition, a common steam boiler has a steam part and a water part, but there is a steam boiler which has almost no water part.

In addition, the dust collector is a device for collecting and removing solid or liquid particulates floating in the gas, and was first used to remove particulate matter contained in the combustion gas of the boiler. However, since the soot and other particulates Are mounted on many chimneys. The fine particles are as fine as about 1 mm to 1 μm, and relatively large ones are easy to remove, but it is difficult to remove fine particles having a degree of adverse effect on the human body. There are many methods of dust collection, such as gravity, filtration, inertia and centrifugal force, using sound waves, and cleaning, among which there are mechanical and electric types. Furthermore, the electrostatic precipitator uses a corona discharge to charge the particles in the agitated gas to separate the charged particles from the gas by electrostatic force. For example, in an electric power plant, an electrostatic precipitator is installed during the gas flow to the chimney to remove much dust or soot contained in the boiler exhaust gas. A DC voltage of tens of thousands of volts is required to collect electricity. The principle of the dust collector is to make positive (+) the cylindrical dust collecting electrode, apply negative (-) DC high voltage to the discharge line at the center of the cylinder, and send the gas containing dust inside under the cylinder, Since it is charged and attached to the inner surface of the cylinder, the gas falling into the upper part of the cylinder is cleaned. Dust accumulated in the cylinder is removed by washing it with water or mechanical shock to the cylinder. The former is called wet type and the latter is called dry type dust collector. The gas flow is in a direction perpendicular to the horizontal direction. The former is suitable for a large amount of gas cleaning, and the latter has an advantage that dust is efficiently collected and the installation area is small. To make DC high voltage, make 40 ~ 70KV by using voltage regulator, special high-voltage transformer, rectifier etc. with 60Hz AC power source. As a rectifier, a high-pressure rectifier tube or a silicon rectifier is used. In either case, a method of limiting the overcurrent when the direct-current high-voltage side is short-circuited should be considered. The electrostatic precipitator is also referred to as a cotrel dust collector since F. G. Cottrell has succeeded in industrial use.

As a prior art related to the present invention, Patent Document 1 discloses a method of separating untreated ultrafine dust contained in flue gas discharged from an electrostatic precipitator at the downstream of an electrostatic precipitator (EP) in a power generating facility or an industrial plant site, The inlet duct (111) and the outlet duct (112) are formed on both sides of the vertical or horizontal direction in which the flue gas flows, and the inlet duct (112) Sectional area enlarged duct 113 having an inner space having an increased sectional area between the upper duct chamber 111 and the outlet duct 112 and an upper duct chamber 113 communicating with the upper and lower portions of the cross- 114) and a lower duct chamber (115); A roll curtain type filter 121 is staggered from the upper duct chamber 114 to the sectional duct enlarged duct 113 and the lower duct chamber 115 of the duct system constructing unit 110, A filter unit 120 for filtering and filtering untreated ultrafine dust contained in the flue gas introduced through the inlet duct 111; A filter driving unit 130 connected to the filter unit 120 so that the roll curtain type filter 121 can be disposed in a zigzag manner and driven to move the roll curtain type filter 121 up and down; A filter drum 140 for driving the roll curtain type filter 121 to be wound when the roll curtain type filter 121 is moved up and down; A dust collecting unit for collecting ultrafine dust filtered by the roll curtain type filter 121 and connected to the lower duct chamber 115 of the duct system constructing unit 110 to collect dust, (150); And a filter exhausting part for performing filter cleaning by spraying compressed air or steam so as to eliminate the clogging phenomenon during use of the roll curtain type filter 121 located at the upper part of the collected fine dust discharging part 150 160) for removing dust from the dust collecting duct. The filtering device according to the prior art has a complicated structure in which the filter is unwound and wound in a forward and reverse direction through a plurality of shafts provided with upper and lower drums and zigzags, and the fine dust is not easily separated from the filter.

Korean Patent Publication No. 10-2016-0084258 (published on July 13, 2016)

In order to solve the above problems, in order to solve the above problem, in the process of treating a combustion gas of a thermal power plant, fine dust discharged from an electrostatic precipitator to an exhaust flue is agglomerated with superheated steam sprayed at a low pressure, And is dried and removed by superheated steam to increase the dust collecting efficiency of the fine dust.

In order to achieve the above object, the present invention provides a dust collecting apparatus comprising: a housing installed in a duct between an electrostatic dust precipitator and a suction blower; A motor installed at an upper end of the housing to generate a rotational force; A power transmitting member for transmitting rotational force of the motor to the inside of the housing; A pair of drive sprockets axially coupled to the power transmitting member and coupled with an axis of a predetermined length; A pair of driven sprockets disposed at a predetermined distance below the drive sprocket and coupled with a shaft having a predetermined length; A chain for transmitting the rotational force of a drive sprocket coupled between the drive sprocket and the driven sprocket to a driven sprocket; A screen filter fixedly coupled between the chains and collecting fine dust while rotating; A first steam pipe installed at the inlet of the housing for spraying the superheated steam supplied from the superheated steam boiler to the surface of the screen filter through a nozzle and a screen filter installed between the drive sprocket and the screen filter wound around the driven sprocket, The superheated steam injected from the first steam pipe collects the fine dust contained in the combustion gas discharged from the electrostatic precipitator into the screen filter, and supplies the superfluous steam to the screen filter through the nozzle. 2 superheated steam injected from a steam pipe is characterized by providing a circulation filtering system using superheated steam for removing fine dust in a combustion gas treatment process of a thermal power plant for drying and removing fine dust collected in a screen filter.

Further, in the present invention, the first steam pipe is supplied with the superheated steam at a low pressure, and the second steam pipe is supplied with the superheated steam at the high pressure.

Further, in the present invention, the screen filter includes a filter for collecting fine dust, a first filter support coupled to the filter surface to support the filter, and a second filter support coupled to the filter back to support the filter can do.

Further, in the present invention, the mesh size of the filter may be configured to be smaller than the mesh size of the first filter support and the second filter support.

Further, in the present invention, the filter may be one of Teflon, glass fiber, aramid or polyimide.

According to the present invention, it is possible to increase the collection efficiency by causing the superheated steam to cohere with the fine dust by injecting the superheated steam of low pressure into the fine dust discharged from the electrostatic precipitator to the exhaust flue, and to supply the fine dust attached to the circulated filter to the high- Superheated steam is injected and physically dried and removed to increase the dust collecting efficiency and differential pressure is not applied to the filter, thereby extending the service life of the filter.

FIG. 1 shows an embodiment of the present invention in which a circulation filtering system using superheated steam for fine dust removal in a combustion gas processing process of a thermal power plant is applied.
FIG. 2 is a side view showing in detail a main structure of a circulation filtering system using superheated steam for removing fine dust in a combustion gas treatment process of a thermal power plant according to the present invention.
3 is a front view showing in detail a main configuration of a circulation filtering system using superheated steam for removing fine dust in a combustion gas processing process of a thermal power plant according to the present invention.
FIG. 4 is a detailed view of the structure of a chain and a screen filter of a circulation filtering system using superheated steam for removing fine dust in a combustion gas treatment process of a thermal power plant according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a circulation filtering system using superheated steam for removing fine dust in a combustion gas treatment process of a thermal power plant according to the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 1, a boiler 1 installed in a thermal power plant burns fossil fuel, and by using heat energy possessed by the combustion gas at a high temperature, water or a heat is heated to generate steam of high temperature and high pressure exceeding atmospheric pressure . The steam generated by the boiler is used to produce mechanical energy by rotating the turbine at a high speed and then to produce electric energy by the generator. The economizer (2) is installed in the flue (3) to heat the feed water using the remaining heat of the combustion gas generated in the combustion chamber of the boiler (1), thereby improving the efficiency of the boiler and increasing the evaporation ability And so on. The flue 3 is a passage through which combusted flue gas passes, and the main components of the flue passing the flue include hydrogen sulfide, carbon dioxide, nitrogen, and the like.

Flue Gas De-Sulfurizer (4) minimizes air pollution by removing sulfur oxides, mainly sulfur dioxide, contained in combustion gases.

An electrostatic precipitator (E / P) 5 collects dust, soot, and the like contained in the combustion gas discharged through the flue 3 at a voltage of tens of thousands of volts and collects the dust. The electrostatic precipitator 5 collects relatively large-sized dust contained in the combustion gas. An induction fan (6) is installed in the flue (3) to artificially extract the combustion gas and discharge it to the chimney (7).

2 and 3, the circulation filtering system 10 is installed in the flue 3 between the electrostatic precipitator 5 and the suction blower 6. The cyclic filtering system 10 is installed in a housing 11 which is installed in a direction substantially perpendicular to the flue 3. In other words, it is preferable that the dust collecting device is installed in a structure in which fine dust in the combustion gas discharged through the electric dust collector 5 through the flue gas 3 can be collected and removed. The inlet of the housing 11 installed vertically to the flue 3 is wider than the width of the flue 3 and the outlet of the housing 11 is again reduced by the width of the flue 3. [ This is for slowing the speed of the combustion gas discharged from the electrostatic precipitator 5 and expanding the dust collecting space to more easily collect and remove fine dust contained in the combustion gas. A separation chamber 12 is provided at the lower end of the housing 11 for collecting and discharging the fine dust that has been collected, dried and removed. In the interior of the separation chamber 12, there is provided an exhaust screw 27 for transferring and discharging the fine dust collected by the motor 26.

The motor 15 is installed at the upper end of the housing 11 to generate a rotating force. The rotational force of the motor 15 is transmitted to the drive sprocket 16 via the power transmitting member 18 through the reduction gear. The power transmitting member may include a sprocket and a chain. The motor 15 may be directly connected to the rotation shaft of the drive sprocket 16.

The drive sprocket 16 is composed of a pair of axially coupled with the power transmitting member 18 and coupled with an axis of a certain length. That is, the drive sprocket 16 is provided with sprockets on both ends of a rotation shaft having a predetermined length. The driven sprocket (17) is installed under the drive sprocket (16) at a certain distance and is constituted by a pair which is coupled with an axis of a predetermined length. That is, the driven sprocket 17 is provided with sprockets at both ends of the rotating shaft of a predetermined length.

The chain 20 transfers the rotational force of the drive sprocket 16, which is coupled between the drive sprocket 16 and the driven sprocket 17, to the driven sprocket 17.

Fig. 4 shows the main part of "A" in Fig. 2, showing the combination of the screen filter 21 and the chain 20. Fig. Here, the screen filter 21 is fixedly coupled between the chains 20 and rotates to collect fine dust. The screen filter 21 is coupled to the chain 20 and collects the fine dust while circulatingly rotating repeatedly and infinitely. That is, the fine dust combined with the superheated steam injected from the first steam pipe 31 is collected in the screen filter 21 that circulates and rotates. The screen filter 21 includes a filter 22 for collecting fine dust and a first filter support 23 coupled to the filter surface to support the filter 22 and is coupled to the filter back surface, ) Are integrally coupled to each other. The first filter support 23 and the second filter support 24 support the filter 22 and provide tensile strength. The first filter support body 23 and the second filter support body 24 are fixedly coupled to the link plate of each chain 20 at regular intervals and between the first filter support body 23 and the second filter support body 24 The filter 22 is inserted and fixed.

It is preferable that the mesh size of the filter 22 is smaller than the mesh size of the first filter support 23 and the second filter support 24. The filter 22 may be formed of any one of Teflon (PTFF), glass fiber (GLASS FIBER), aramid (ARAMID) and polyimide having excellent chemical resistance.

The first steam pipe 31 is installed at the inlet of the housing 11 and injects superheated steam supplied from the superheated steam boiler 30 onto the surface of the screen filter 21 through the nozzle 32. The first steam pipe (31) is branched into a plurality of nozzles (32) mounted at the ends thereof, and the superheated steam is sprayed. The superheated steam particles injected from the first steam pipe (31) are combined with the fine dust contained in the combustion gas.

The second steam pipe 33 is installed between the drive sprocket 16 and the screen filter 21 wound around the driven sprocket 17 to rotate the superheated steam supplied from the superheated steam boiler 30 through the nozzle 34 And is sprayed onto the surface of the filter 21. That is, the superfluous steam injected from the second steam pipe (33) provided inside the screen filter (21) is used to dry and remove fine dust adsorbed on the outer surface while the screen filter (21) do.

The superheated steam injected from the first steam pipe 31 collects the fine dust contained in the combustion gas discharged from the electrostatic precipitator 5 into the screen filter 21 and the superheated steam injected from the second steam pipe 33 The fine dust collected in the screen filter 21 is dried and removed.

Also, the superheated steam boiler 30 can supply the superheated steam of low pressure to the first steam pipe 31 and the superheated steam of high pressure to the second steam pipe 33, respectively. This allows the superheated steam of low pressure to be supplied to the first steam pipe 31 in order to adsorb the fine dust contained in the combustion gas to the screen filter 21. In order to separate and remove the fine dust adsorbed to the screen filter 21, The superheated steam of the second steam pipe 33 may be supplied to the second steam pipe 33.

Accordingly, the operation of the circulation filtering system using the superheated steam for removing fine dust in the combustion gas processing process of the thermal power plant of the present invention will be described.

A large amount of dust is generated in the combustion process in the boiler 1 of the thermal power plant and relatively large dust is removed while the combustion gas passes through the electrostatic precipitator 5 after the combustion is desulfurized through the stamper 4. Thereafter, the fine dust discharged into the exhaust flue 3 of the electrostatic precipitator 5 is combined with the superheated steam injected through the nozzle 14 by the first steam pipe 13. The fine dust combined with the superheated steam is trapped in the filter 22 of the screen filter 21 which is fixedly coupled to the chain 20 between the drive sprocket 16 and the driven sprocket 17 in the housing 11, do. Then, the superheated steam is injected from the second steam pipe (25) disposed inside the circularly rotating screen filter (21) toward the filter (22). Therefore, the fine dust collected in the filter 22 is dried by the high-pressure superheated steam sprayed from the back surface, and is separated from the filter 22. The fine dust removed from the filter 22 is supplied to the separation chamber 12 at the lower portion of the housing 11 and is dropped into a discharge screw 27 rotating by the rotational force of the motor 26 and then discharged along the discharge screw 27 do. Thereafter, fine dust is removed from the combustion gas passing through the circulation filtering system 10, and is discharged to the atmosphere through the chimney 7 via the blower 6. Therefore, the exhaust gas discharged into the atmosphere contains no fine dust, which can minimize environmental problems.

While the invention has been shown and described with respect to the specific embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. Anyone with it will know easily.

1: boiler 2: economizer 3: year 4: combustion stall 5: electrostatic precipitator 6: suction blower 7: chimney 10: circulation filtering system 11: housing 12: separation chamber 15: motor 16: drive sprocket 17: : Power transmission member 20: Chain 21: Screen filter 22: Filter 23: First filter support 24: Second filter support 26: Motor 27: Discharge screw 30: Superheated steam boiler 31: First steam pipe 32: Steam tube 34: nozzle

Claims (5)

A housing installed in the duct between the electrostatic precipitator and the suction blower;
A motor installed at an upper end of the housing to generate a rotational force;
A power transmitting member for transmitting rotational force of the motor to the inside of the housing;
A pair of drive sprockets axially coupled to the power transmitting member and coupled with an axis of a predetermined length;
A pair of driven sprockets disposed at a predetermined distance below the drive sprocket and coupled with a shaft having a predetermined length;
A chain for transmitting the rotational force of a drive sprocket coupled between the drive sprocket and the driven sprocket to a driven sprocket;
A screen filter fixedly coupled between the chains and collecting fine dust while rotating;
A first steam pipe installed at the inlet of the housing for spraying overheated steam supplied from the superheated steam boiler to the surface of the screen filter through a nozzle,
And a second steam pipe installed between the drive sprocket and the screen filter wound around the driven sprocket and spraying superheated steam supplied from the superheated steam boiler to the surface of the screen filter through the nozzle,
The superheated steam injected from the first steam pipe collects the fine dust contained in the combustion gas discharged from the electrostatic precipitator into the screen filter and the superheated steam injected from the second steam pipe dries and removes the fine dust collected in the screen filter. A Circulating Filtering System Using Superheated Steam for Removing Fine Dust in Combustion Gas Treatment Process of Thermal Power Plants.
The method of claim 1, wherein the first steam pipe is supplied with a superheated steam at a low pressure and the second steam pipe is supplied with a superheated steam at a high pressure. In the combustion gas treatment process of the thermal power plant, system.
The screen filter according to claim 1, wherein the screen filter includes a filter for collecting fine dust, a first filter support coupled to the filter surface to support the filter, and a second filter support coupled to the filter back to support the filter A cyclic filtering system using superheated steam for the removal of fine dust in a combustion gas treatment process of a thermal power plant.
4. The system of claim 3, wherein the mesh size of the filter is smaller than the mesh size of the first filter support and the second filter support, wherein the superheated steam is used to remove fine dust in a combustion gas processing process of a thermal power plant.
The system of claim 1, wherein the filter is one of Teflon, glass fiber, aramid, or polyimide, and is a circulation filtering system using superheated steam for fine dust removal in a combustion gas processing process of a thermal power plant.

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