KR101148977B1 - Method and system for treating high-temperature exhaust gas - Google Patents

Abstract

The present invention is proportionally before the filter dust collection means so as to recover and reuse the extracted raw material contained in the hot exhaust gas in the melting process for the production of the secondary product (extracting material) from the raw material introduced into the high temperature treatment furnace, such as a melting furnace. Cooling is below the melting point of the extraction raw material contained in the exhaust gas by the controlled supplying air and maximized the collection rate by collecting by the filter cloth, and at the same time prevents the deposition of the extraction material of the filter cloth as much as possible to reduce the pore blockage to ensure the long life do.

In addition, by using the waste heat of the exhaust gas, energy recycling, which is the combustion air of the burner supplied to the high temperature treatment furnace, is provided, so that it is possible to provide maximum fuel savings due to the operation of the high temperature treatment furnace.

High temperature treatment, exhaust gas, raw material reuse, melting point below, differential pressure, waste heat recycling

Description

High temperature exhaust gas treatment method and apparatus {METHOD AND SYSTEM FOR TREATING HIGH-TEMPERATURE EXHAUST GAS}

The present invention maximizes the economics by the maximum recovery of the extracted raw material contained in the hot exhaust gas generated in the melting process of producing a secondary product (extract raw material) from the raw material introduced into a high temperature treatment furnace such as a melting furnace and high temperature treatment by waste heat recycling The present invention relates to a method and apparatus for treating hot exhaust gas that can provide fuel savings due to furnace operation.

In general, a high temperature treatment furnace such as a melting furnace for processing a mineral raw material for the production of secondary products (extract raw materials) is to treat the hot exhaust gas discharged to the outside within the standard value specified by the regulations.

That is, in the process of melting the raw material (mineral, powder), the heavy metal raw material, which is a secondary product (extract raw material) to be extracted, is melted into fine particles and discharged in a solid and liquid state in the hot exhaust gas.

In the case of discharging the hot exhaust gas in such a state as it is, serious environmental pollution is caused, and the hot exhaust gas is filtered to a reference value capable of releasing to the air and discharged in a harmless state.

In other words, in order to process the dust (particulates) in the hot exhaust gas, it is collected separately from the gaseous substance, which is collected by a filter dust collector having a high temperature ceramic filter (bag filter) as such dust collecting means.

The treatment technology for the high temperature exhaust gas discharged from such a high temperature treatment furnace has been disclosed with various techniques.

In order to prevent the filter dust collection equipment from being damaged by the high temperature exhaust gas, such a treatment technology inevitably forms a gas cooling device at the front of the filter dust collecting equipment and injects the gas exhaust gas in a cool state to protect the filter dust collecting equipment. And effective separation of dust.

However, the exhaust gas cooling means implemented in such a conventional high temperature exhaust gas treatment technology has the ultimate purpose simply to protect the filter.

As a result, the fine particles contained in the hot exhaust gas in the molten state were deposited on the filter cloth of the bag filter, and thus the life of the expensive ceramic filter (bag filter) was not guaranteed.

Thus, the found means reacts with the hot exhaust gas and the chemically treated gas and collects the molten dust (flying material) in the hot exhaust gas without depositing it on the filter cloth.

As a result, the high-temperature exhaust gas treatment apparatus for obtaining a desired secondary product (extract raw material) by melting such raw materials does not require a reuse means by collecting the extracted raw material contained in the exhaust gas, and is subject to forced chemical treatment. As a means for collecting and treating waste as waste, there is a disadvantage in that waste of raw materials is severe and the cost of operating the apparatus is excessively used.

In addition, effective energy saving due to the operation of a high temperature treatment furnace such as a melting furnace due to the waste heat recycling means of the exhaust gas is not established.

The high temperature exhaust gas treatment method and apparatus of the present invention for solving the conventional problems as described above,

Smooth production of secondary products (extract materials) required by melting treatment of raw materials (powders or minerals) and collection of extract raw materials in dust discharged in high-temperature exhaust gas to maximize economic efficiency by recycling and recycling waste heat of exhaust gases The purpose is to maximize the savings of fuel used by

In addition, the present invention has another object to enable long-term use by the efficient operation of the filter dust collecting means.

The high temperature exhaust gas treatment apparatus of the present invention for achieving the above object,

A high temperature treatment furnace for separating and extracting a required secondary product (extracting material) by melt-decomposing a raw material (powder or mineral);

Filter dust collecting means for filtering and collecting the extraction material contained in the hot exhaust gas discharged in the molten state in the high temperature treatment furnace;

Cooling means for cooling to a predetermined temperature below a melting point of the extraction raw material contained in the exhaust gas in conjunction with a temperature before the introduction of the filter dust collecting means of the high temperature exhaust gas;

Air preheating means for supplying preheated inlet air preheated to the heating gas burner in the high temperature treatment furnace while cooling and discharging the hot exhaust gas filtered by the filter dust collecting means with the inlet air; And

The exhaust air is sucked by the air preheating means to control the blowing speed so as to maintain the internal pressure of the high temperature treatment furnace at the maximum 0 mmAq at the same time as the external discharge to prevent the extraction of the raw material contained in the hot exhaust gas in the high temperature treatment furnace Manned blowing means; Characterized in that it comprises a.

The cooling means is installed to maintain below the melting point of the raw material by natural cooling by adjusting the amount of air by proportional control by an actuator (actuator).

When the pressure difference between the inlet and outlet of the filter dust collecting means rises above the set value, it is characterized in that the filter cloth cleaning means for cleaning to maintain a smooth flow of the exhaust gas by pouring the compressed air from the top of the filter cloth.

In addition, the high temperature exhaust gas treatment method according to the present invention,

Melting step of melting the raw material in the high temperature treatment furnace to separate the secondary product (extract raw material);

A filter dust collecting step for collecting the extract raw material by filtering the filter cloth by putting it into the filter dust collecting means in a state of cooling below the melting point of the extract raw material contained in the high temperature exhaust gas of the high temperature treatment furnace;

A preheat supply step of discharging the hot exhaust gas filtered and discharged in a naturally cooled state by heat exchange with inlet air and simultaneously supplying preheated inlet air to a heating burner of the high temperature treatment furnace; And

A manned blowing step of sucking the exhaust gas and simultaneously maintaining the internal pressure of the high temperature treatment furnace at a maximum of 0 mmAq to prevent air from being scattered in the high temperature exhaust gas of the high temperature treatment furnace; Characterized in that it comprises a.

The filter dust collecting step is characterized in that the high-temperature exhaust gas is naturally cooled by adjusting the amount of air by proportional control of the actuator before filtration by the filter cloth and kept in the state below the melting point of the extraction raw material.

The filter dust collecting step is characterized in that to wash the filter cloth by blowing the compressed air when the pressure difference between the inlet and the outlet is greater than the set value.

The preheating supplying step is characterized in that the exhaust gas cooled by heat exchange between the hot exhaust gas filtered out and the inlet air is discharged, and the preheated inlet air is used as combustion air of the heating burner in the high temperature treatment furnace.

Therefore, according to the present invention, it is possible to prevent the loss of expensive raw materials in the melting process of the raw materials by the high temperature treatment furnace to prevent the economical and environmental pollution as much as possible, and to increase the fuel saving effect by recycling the waste heat.

In addition, the present invention is easy to operate depending on the raw materials to be applied, thereby increasing the range of use, thereby ensuring reliability.

Key features of the present invention are to ensure the economics by reusing the extraction raw materials discharged in the state contained in the hot exhaust gas during the melting process of the raw materials and to actively prevent the environmental pollution by the unauthorized release of the extract raw materials and recycling the waste heat It can be specified as a technique that can save the operating fuel in the high temperature treatment by the.

Hereinafter, the configuration and operation of the present invention will be described in detail with reference to the accompanying drawings.

1 is a structural diagram schematically showing the structure of a high temperature exhaust gas treatment apparatus according to an embodiment of the present invention, a high temperature treatment furnace 100 such as a melting furnace, filter dust collecting means 200, air preheating means 300 and It includes a component of the manned blowing means (400).

At this time, the cooling means 500 is configured in the pipe P / L of the high temperature treatment furnace 100 and the filter dust collecting means 200.

The high temperature treatment furnace 100 is a raw material in the form of a powder or mineral containing a secondary product (extract raw material) to be extracted is introduced by the supply port 110, 850 ℃ ~ by a heat source (LNG burner: 120) It melts by high heat of about 1000 degreeC.

The secondary product (extract raw material) thus melted and separated is discharged from the discharge port 130 and collected in a solidified state by cooling.

At this time, the high temperature exhaust gas discharged from the high temperature treatment furnace 100 is contained in the extraction raw material in a molten state and discharged as it is.

The hot exhaust gas thus discharged is introduced into the filter dust collecting means 200.

As shown in FIG. 2, the filter dust collecting means 200 has a hopper-shaped housing 210 having a lower inlet 220 and an upper outlet 230, and between the mouth and outlet 220 and 230. The filter cloth 240 of the ceramic material and the filter cloth is formed on the upper side of the filter cloth is compressed in the upper portion of the filter cloth 240 when the pressure difference between the pressure on the inlet 220 side and the outlet 230 side reaches a set differential pressure value It consists of a filter cloth washing means 250 for blowing air.

The hot exhaust gas is supplied in a cooled state below the melting point of the extraction raw material by the cooling means 500 configured in the pipe P / L before the introduction of the filter bag 200.

As a result, the extraction raw material contained in the high temperature exhaust gas is filtered without being deposited on the filter cloth 240 and is collected at the bottom of the housing 210 to be reused.

The cooling means 500 is configured in the pipe (P / L) connected to the inlet 220 of the filter dust collecting means 200,

A temperature control damper 510 configured at an inlet 220 side of the housing 210;

An actuator 520 for driving control of the temperature regulating damper;

It is composed of a temperature sensor 530 is configured at the outlet 230 of the housing 210 to drive the actuator 520 by sensing.

The cooling means 500 is the cooling control is set in accordance with the raw material to be melted in the high temperature processing furnace (100).

That is, when the temperature of the hot exhaust gas discharged through the outlet 230 of the housing 210 is higher than the set temperature compared to the melting point temperature of the raw material extracted from the raw material, the actuator 520 by the sensor 530. Drive) to control the temperature control damper 510 to cool below the melting point temperature of the raw material to regulate the supply of incoming air.

The actuator is preferably a MODUTROL MOTER, which is a driver for repeatedly placing a valve, a damper, a slide, and the like in the correct position. The modulotrol motor detects and controls the exact position by an electronic circuit composed of an encoder or a potentiometer, or precisely controls and drives the rotation angle of the shaft by a digital or analog signal.

In this way, the extraction raw material contained in the high-temperature exhaust gas is introduced through the lower inlet 220 of the housing 210 in a state of being cooled below the melting point, and filtered through the filter cloth 240 in the inner center, thereby extracting the extraction raw material into the housing ( The exhaust gas is collected and collected at the lower portion of the 210 and at the same time, the filtered exhaust gas is discharged through the upper side outlet 230.

In the process of obtaining the extraction raw material filter, the filter cloth 240 of the filter dust collecting means 200 is blocked by the pores in the long-term use, the filtration efficiency is lowered, so that the cleaning is periodically performed by the filter cloth washing means 250.

The filter cloth cleaning means 250 is a differential pressure setting unit 260,

A pressure gauge 270 for detecting the differential pressure between the inlet 220 and the outlet 230 of the housing 210 constituting the filter dust collecting means 200 by the differential pressure setting part;

A detection sensor 280 for controlling the opening of the valve 291 by detecting when the differential pressure of the pressure gauge reaches a set value;

Compressor 290 for supplying compressed air through the valve (291).

The filter cloth cleaning means 250 is intended for periodic cleaning to provide a smooth gas flow by shaking the pores of the filter cloth 240 in the process of using the filter bag 200.

That is, the differential pressure setting unit 260 sets the pressure difference between the inlet 220 and the outlet 230 of the housing 210 through the pressure gauge 270, and the pores of the filter cloth 240 are blocked. When the differential pressure set value is reached, the detection sensor 280 detects.

By opening the valve 291 under the control of the differential pressure setting unit 280 by the detection of the sensor 280, the filter cloth 240 is blown off by the strong compressed air from the upper portion of the filter cloth 240 by the compressor 290. At the same time as the washing of the extract) the raw material blocked in the pores are collected in the lower discharge port 211 of the housing 210.

Thus, the extraction raw material collected in the lower discharge port 211 is opened by the operation of the pneumatic cylinder 212 of the slide gate 213, is collected and transported by the collecting and conveying means (215).

The hot exhaust gas filtered by the filter dust collecting means 200 is discharged to the outside by the guided blowing means 400 in a further cooled state by heat exchange with air forcedly drawn in via the air preheating means 300, The air is preheated and supplied to the combustion air of the heating burner 120 of the high temperature furnace 100.

As shown in FIG. 3, the air preheating means 300 includes a discharge tube 310 and an inlet tube 320 capable of mutual heat exchange, and the discharge tube 310 is the filter dust collecting means 200. It is connected to the outlet 230 and the pipe (P / L) of the exhaust gas is introduced by the suction of the inlet blowing means 400 and at the same time the inlet tube 320 is drawn air by the blowing fan 350 installed outside It is introduced by the forced supply of heat exchange with each other.

That is, the hot exhaust gas is further cooled to be discharged to the outside (in the air) by the induction blower means 400, and the inlet air is preheated in the heating burner 120 of the high temperature treatment furnace 100. It is supplied to the combustion air.

Therefore, the waste heat of the high temperature exhaust gas is utilized as a preheating means of combustion air in the heating burner 120 can reduce the fuel consumption by energy recycling.

In addition, the attracting blowing means 400 is composed of a suction fan 410 configured in the lower portion of the chimney to discharge to the atmosphere.

The suction fan 410 is driven by one side motor 420, the motor 420 is controlled by the controller 430 that can be set by sensing the internal pressure of the high temperature processing furnace (100).

The guided blowing means 400 controls the blowing speed of the suction fan 410 to maintain the internal pressure at a maximum of 0 mmAq when the raw material is introduced into the high temperature processing furnace 100 under the control of the controller 430. By controlling to prevent scattering of raw materials contained in the hot exhaust gas of the high temperature treatment furnace 100, the internal scattering raw materials of the high temperature treatment furnace 100 may be filtered and collected by the filter dust collecting means 200.
Maintaining the internal pressure of the high temperature treatment furnace 100 at the maximum 0 mmAq mentioned above is to efficiently maintain the temperature of the high temperature treatment furnace 100 and to prevent the loss of the extraction raw material by preventing the scattering of the exhaust gas as much as possible. It is in a ship.
In other words, if the internal pressure of the high temperature treatment furnace 100 increases with the negative pressure (-mmAq) based on 0 mmAq, the speed of temperature exiting is increased, and the fuel input amount due to the temperature drop increases, resulting in low economic efficiency, and high temperature exhaust. The increase in scattering of raw materials contained in the gas increases the amount of extraction of the extracted raw materials excessively, and the dust collection performance is reduced,
When the positive pressure (+ mmAq) is increased, the extraction material contained in the exhaust gas due to the increase in the internal pressure is scattered to the supply port 110 of the high temperature treatment furnace 100, so as to prevent the loss of flying to the outside to the maximum. The internal pressure of the furnace 100 is to be maintained at 0 mmAq as much as possible.

Example

Ammonium metavanadate (NH ₄ VO ₃ ) powder powder (raw material) was added and melted while the high temperature furnace 100 was heated to 850 ° C. or higher, and the secondary product (extract raw material) was oxidized through the outlet 130. Vanadium (V ₂ O ₅ ) was collected.

The hot exhaust gas discharged from the high temperature treatment furnace 100 during the melting of the extracted raw material is discharged including the extraction material of ammonia gas and vanadium pentoxide (V ₂ O ₅ ) in a molten state.

Vanadium pentoxide (V ₂ O ₅ ), the extraction material, is used in sulfuric acid production catalysts, catalysts for producing phthalic anhydride of naphthalene, catalysts for the production of maleic anhydride from benzene, raw materials for the production of vanadium compounds, fiber dyeing, coloring, and other catalysts.

And the extraction raw material contained in the discharged high-temperature exhaust gas can be collected by filtration by the filter dust collecting means 200 can be reused.

The high temperature exhaust gas is cooled to 500 to 550 ° C. which is less than or equal to the melting point (about 650 ° C.) of the vanadium pentoxide (V ₂ O ₅ ), which is the extraction material, by the cooling means 500 installed before introduction of the dust collecting filter 200. The control was reused as a filter collection in the filter cloth 240.

The filter cloth 240 was used as a ceramic series used at high temperature (1000 ° C.).

Pore of the filter cloth 240 in such a filter dust collection process by the filter cloth washing means 250 to induce a smooth flow of the exhaust gas was able to maximize the device efficiency by automatic differential pressure management.

The air preheating means 300 pre-heats and supplies the combustion air of the heating burner 120, which is a heating source of the high temperature treatment furnace 100, to the waste heat of the exhaust gas, thereby making it always stable to operate, and preheating to a high temperature (about 350 ° C). By supplying the air, it was possible to save about 20% of the fuel used.

1 is a structural diagram schematically showing the structure of a high temperature exhaust gas treatment apparatus according to an embodiment of the present invention.

2 is an enlarged view of a portion of the filter dust collecting means of FIG.

Figure 3 is an enlarged view showing the connection structure of the air preheating means and guided blowing means of Figure 1 and the high temperature treatment furnace.

DESCRIPTION OF REFERENCE NUMERALS

100: high temperature treatment furnace 110: supply port

120: heat source (LNG burner) 130: outlet

200: filter dust collecting means 210: housing

220: inlet 230: outlet

240: filter cloth 250: filter cloth cleaning means

300: air preheating means 310: discharge tube

320: incoming tube 350: blowing fan

400: manned blowing means 410: suction fan

430: controller 500: cooling means

510: temperature control damper 520: actuator

530: temperature sensor P / L: piping

Claims (9)

delete Filtering and collecting the raw material (powder or mineral) by the high temperature treatment furnace for separating and extracting the required secondary products (extract material) by melting and decomposition, and the extraction raw material contained in the hot exhaust gas discharged in the molten state in the high temperature treatment furnace Cooling means for cooling to a set temperature below the melting point of the extraction raw material contained in the exhaust gas in conjunction with the pre-intake temperature of the filter dust collecting means, the filter dust collecting means of the hot exhaust gas, and the high temperature filtered by the filter dust collecting means Air preheating means for exchanging the exhaust gas with the inlet air to cool and discharge the same, and supplying the preheated inlet air to the heating gas burner of the high temperature treatment furnace, and sucking the exhaust gas from the air preheating means to discharge the high temperature Manned blowing to prevent air from flying into the high-temperature treatment furnace by controlling the blowing speed to keep the internal pressure of the treatment furnace at the maximum 0 mmAq In the processing apparatus of the high-temperature exhaust gas containing the stage, The cooling means is a high temperature exhaust gas treatment apparatus, characterized in that it is installed to maintain below the melting point of the raw material by natural cooling by adjusting the amount of air by proportional control by an actuator (actuator). 3. The method of claim 2, The filter dust collecting means has a hopper-shaped housing having a lower inlet and an outlet on the upper side, a filter cloth of a ceramic material configured inside the mouth and an outlet, and an upper portion of the filter cloth, the pressure at the inlet side and the outlet side The apparatus for treating high temperature exhaust gas, characterized in that the filter cloth washing means for washing by blowing compressed air from the upper portion of the filter cloth when the pressure difference reaches a set differential pressure value. 3. The method of claim 2, The cooling means and the temperature control damper configured on the housing inlet side of the filter bag; An actuator for driving and controlling the temperature regulating damper; And a temperature sensor configured at the outlet of the housing of the filter and configured to drive the actuator by sensing. The method of claim 3, The filter cloth cleaning means and the differential pressure setting unit; A pressure gauge for detecting the differential pressure between the inlet and the outlet of the housing constituting the filter dust collecting means by the differential pressure setting portion; A detection sensor for detecting when the differential pressure of the pressure gauge reaches a set value and controlling opening of the valve; Apparatus for treating hot exhaust gases, characterized in that the compressor for supplying compressed air through the valve. delete Melting step of melting the raw material in the high temperature treatment furnace to separate the secondary product (extract raw material), and put into the filter bag in the state of cooling to below the melting point of the extraction raw material contained in the exhaust gas of the high temperature treatment furnace to the filter cloth The filter dust collecting step to collect the extracted raw material by filtration, and the preheating to discharge the hot exhaust gas from the filtration discharge in a state of natural cooling by heat exchange with the inlet air and to supply the preheated inlet air to the heating burner of the high temperature treatment furnace. A hot air exhaust gas treatment method comprising a feeding step and a suction air blowing step of sucking air from the exhaust gas and simultaneously maintaining the internal pressure of the high temperature furnace at a maximum of 0 mmAq to prevent air from being diffused into the high temperature furnace. , In the filter dust collecting step, before the filtration by the filter cloth, the hot air exhaust gas is naturally cooled by adjusting the amount of air by proportional control of the actuator, and the hot air exhaust gas is maintained in the state of being kept below the melting point of the extraction raw material. Way. The method of claim 7, wherein In the filter dust collecting step, when the differential pressure between the inlet and the outlet of the filter dust collecting means is greater than or equal to a predetermined value, the compressed air is blown to wash the filter cloth. delete

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