CN216295771U - Low-temperature SCR denitration device for waste gas generated in smelting of nonferrous metal Kaldo furnace - Google Patents
Low-temperature SCR denitration device for waste gas generated in smelting of nonferrous metal Kaldo furnace Download PDFInfo
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- CN216295771U CN216295771U CN202121029331.XU CN202121029331U CN216295771U CN 216295771 U CN216295771 U CN 216295771U CN 202121029331 U CN202121029331 U CN 202121029331U CN 216295771 U CN216295771 U CN 216295771U
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- 229910052751 metal Inorganic materials 0.000 title claims abstract description 19
- 239000002184 metal Substances 0.000 title claims abstract description 19
- 238000003723 Smelting Methods 0.000 title claims abstract description 17
- 239000002912 waste gas Substances 0.000 title claims abstract description 16
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 107
- 239000003546 flue gas Substances 0.000 claims abstract description 107
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 74
- 239000003054 catalyst Substances 0.000 claims abstract description 52
- 238000001514 detection method Methods 0.000 claims abstract description 29
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- 238000002156 mixing Methods 0.000 claims abstract description 20
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- 230000003068 static effect Effects 0.000 claims abstract description 14
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- 229910021529 ammonia Inorganic materials 0.000 claims description 20
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 18
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 18
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- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 48
- 238000006243 chemical reaction Methods 0.000 description 22
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- 239000012895 dilution Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 238000010531 catalytic reduction reaction Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
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- 238000006479 redox reaction Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- GFNGCDBZVSLSFT-UHFFFAOYSA-N titanium vanadium Chemical compound [Ti].[V] GFNGCDBZVSLSFT-UHFFFAOYSA-N 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
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Abstract
The utility model relates to a low-temperature SCR denitration device for waste gas of nonferrous metal Kaldo furnace smelting, which comprises a heat exchanger, a gas afterburning device, an ammonia gas preparation and injection device and an SCR reactor, wherein the heat exchanger, the gas afterburning device, the ammonia gas preparation and injection device and the SCR reactor are sequentially arranged from the direction of flue gas entering; the smoke detection and feedback device is arranged on the smoke inlet pipeline; the SCR reactor comprises a horizontal denitration reactor body, an ammonia-smoke mixing section and a catalytic reaction section are sequentially arranged in the horizontal denitration reactor body from the direction of a smoke inlet, the ammonia-smoke mixing section comprises a plurality of static mixers sequentially arranged from the direction of the smoke inlet, and the catalytic reaction section comprises a plurality of catalyst bed layers sequentially arranged from the direction of the smoke inlet; an electric heater is arranged on the outer side of the lower part of the horizontal denitration reactor body of the SCR reactor.
Description
Technical Field
The utility model belongs to the technical field of flue gas denitration and purification, and particularly relates to a low-temperature SCR denitration device for waste gas from metallurgy of a nonferrous metal Kaldo furnace.
Background
In China, nitrogen oxide is one of main pollutants for air pollution, and the emission of nitrogen oxide not only can form acid rain, but also can form photochemical smog and PM 2.5. In order to control the pollution of nitrogen oxides and acid rain, the state increases the treatment strength of the nitrogen oxides in the flue gas, requires the denitration treatment of the flue gas, and weakens the influence of the nitrogen oxides on the ecological environment to the greatest extent.
The SCR denitration technology is one of nitrogen oxide pollution control technologies widely applied at present, and derives denitration treatment processes aiming at different flue gas working conditions according to different activity temperatures of used catalysts, and mainly comprises medium-high temperature, medium-low temperature and low-temperature SCR denitration.
In the non-ferrous metal smelting process, the amount of flue gas discharged by the Kaldo furnace is small (generally not more than 10 ten thousand meters)3The pollution characteristics of the catalyst are mainly shown as high acid content and high nitrogen oxide content, so that after the smoke of a general Kaldo furnace is discharged, wet desulphurization and deacidification treatment is firstly carried out to remove acid mist components in the smoke, the temperature of the smoke is further reduced to 50-60 ℃ in the process, the temperature range is far lower than the traditional medium-high temperature (280 plus 320 ℃) denitration temperature, the low-temperature smoke at 50-60 ℃ is heated to the medium-high temperature catalyst activity temperature range, the energy consumption is greatly increased, and the investment and operation cost is correspondingly higher.
In order to save energy and reduce cost, the development of the energy-saving low-temperature SCR denitration reaction device has great practical significance. With the increasingly mature and perfect production process technology of the low-temperature catalyst, the low-temperature catalysts with low price and good high efficiency appear in succession, so that the development of the low-temperature SCR denitration process and device under the complex working condition becomes possible.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the problem of flue gas purification and denitration treatment of a Kaldo furnace. Discloses a low-temperature SCR denitration device, which is a low-temperature SCR denitration device for waste gas in smelting of a nonferrous metal Kaldo furnace. The device process is mainly designed for the characteristics of low temperature, small flue gas amount and high NOx concentration of flue gas of a Kaldo furnace after wet desulphurization.
The technical scheme of the utility model is as follows: a low-temperature SCR denitration device for waste smelting gas of a nonferrous metal Kaldo furnace comprises a heat exchanger, a fuel gas afterburning device, an ammonia gas preparation and injection device and an SCR reactor which are sequentially arranged from the direction of flue gas inlet; the smoke detection and feedback device is arranged on the smoke inlet pipeline;
the SCR reactor comprises a horizontal denitration reactor body, an ammonia-smoke mixing section and a catalytic reaction section are sequentially arranged in the horizontal denitration reactor body from the direction of a smoke inlet, the ammonia-smoke mixing section comprises a plurality of static mixers sequentially arranged from the direction of the smoke inlet, and the catalytic reaction section comprises a plurality of catalyst bed layers sequentially arranged from the direction of the smoke inlet;
an electric heater is arranged on the outer side of the lower part of the horizontal denitration reactor body of the SCR reactor.
Furthermore, the flue gas outlet direction of the SCR reactor is sequentially connected with a heat exchanger, an induced draft fan and a chimney.
Further, the ammonia gas preparation and injection device comprises an ammonia injection device and an ammonia water storage tank connected with the ammonia injection device; the method comprises the steps of preparing ammonia gas by evaporating 20% concentrated ammonia water serving as a raw material, diluting the ammonia gas to 5% of safe concentration by a dilution fan, and spraying the diluted ammonia gas into a flue gas pipeline through an ammonia spraying device to mix with the flue gas.
Still further, the flue gas detection and feedback device comprises a NOx detection and signal feedback device and a temperature detection and signal feedback device; the electric heater is connected with the temperature detection device.
Still further, the temperature detection device is a temperature detection and signal feedback device.
Furthermore, the catalytic reaction section is provided with 3 catalyst bed layers, the catalyst is a low-temperature vanadium titanium-based catalyst, and the active reaction temperature of the catalyst is 200 ℃; the flue gas mixing section consists of 2-3 static mixers.
And furthermore, a soot blower is arranged at the front end of each layer of catalyst bed layer in the SCR reactor.
Furthermore, a heat tracing device is also arranged on the flue gas inlet pipeline of the SCR reactor; the heat exchanger is a plate heat exchanger, heat exchange fins of the plate heat exchanger adopt SS304 and SMO254, and the plate heat exchanger consists of a heat exchange core module, a self-supporting frame, hot side flue gas and cold side flue gas inlet and outlet variable diameter parts; the smoke afterburning device is a gas preheater device; a manhole is arranged on a horizontal denitration reactor body of the SCR reactor, and a valve plate is arranged at the bottom of a dust collecting groove at the lower part of the horizontal denitration reactor body.
A low-temperature SCR denitration process for waste smelting gas of a nonferrous metal Kaldo furnace comprises the following steps:
firstly, heating low-temperature flue gas by a heat exchanger, then further heating by a gas afterburning device to a temperature range of a catalyst reaction temperature in an SCR reactor, wherein the SCR reactor is of a horizontal structure, and the flue gas flows in a horizontal direction;
secondly, preparing ammonia gas by using concentrated ammonia water stored in an ammonia water storage tank area as a raw material, injecting the ammonia gas into flue gas subjected to gas afterburning and temperature rise, and fully mixing the flue gas and the ammonia gas in a static mixer in the flowing process of a flue and then feeding the mixture into a catalyst bed layer of an SCR reactor; the catalyst of the catalyst bed layer is a low-temperature SCR denitration catalyst, and the reaction temperature of the catalyst is 180 DEG and 200 ℃;
thirdly, in the process of passing through the catalyst, under the catalytic reaction of the catalyst, the ammonia gas in the flue gas and the nitrogen oxide undergo oxidation-reduction reaction to generate nontoxic and harmless N2And H2O, thereby removing nitrogen oxides and purifying the flue gas.
Further, the low-temperature SCR denitration process for the waste gas from the metallurgy of the nonferrous metal Kaldo furnace comprises the following steps: the inlet 60 +/-1 ℃ low-temperature flue gas firstly enters a heat exchanger to exchange heat with the purified 200 ℃ high-temperature flue gas, the temperature is raised to 170 ℃, then the flue gas is further heated by a gas afterburning device, the heating amount is controlled by a temperature detection and signal feedback device (3), the 170 ℃ raw flue gas is heated to 210 +/-1 ℃ higher than the temperature of SCR catalytic reaction, and then an ammonia spraying device is used for metering and spraying a denitration reducing agent;
the denitration reducing agent is prepared by evaporating and diluting 20% ammonia water, the 20% ammonia water is stored in an ammonia water storage tank, the concentrated ammonia water is evaporated by steam and diluted into 5% ammonia gas by a dilution fan, and then the ammonia gas is sprayed into a flue gas pipeline to be mixed with flue gas through an ammonia gas spray gun of an ammonia spraying device under the accurate metering control of NOx detection and signal feedback devices, and at the moment, the temperature of the flue gas is reduced to a catalytic reaction temperature range of 200 +/-1 ℃ due to the mixing of the ammonia gas;
the flue gas after ammonia spraying enters a horizontal denitration reactor body of an SCR (selective catalytic reduction) reactor, the flue gas firstly flows through a mixing section consisting of 2-3 static mixers to be fully mixed, then enters a catalyst bed layer, and nitrogen oxide and ammonia gas in the flue gas in the catalyst are subjected to catalytic reduction reaction to generate N2And H2O, removal of NO and NO2And the nitrogen oxides are obtained by the following main reaction chemical equation:
4NH3+4NO+O2→4N2+6H2O
4NH3+2NO2+O2→3N2+6H2O
the temperature of the flue gas purified by the denitration reaction is 200 ℃, in order to fully utilize the waste heat of the flue gas and save energy, the clean flue gas at 200 ℃ is introduced into a heat exchanger, the temperature of the heat exchange raw flue gas is used for increasing the temperature of the heat exchange raw flue gas, the temperature of the clean flue gas discharged from the heat exchanger is reduced to 90 +/-1 ℃, and finally the clean flue gas is discharged through a chimney under the action of an induced draft fan.
The utility model has the technical effects that: the device disclosed by the utility model has the advantages that the denitration efficiency is improved, the utilization rate of the denitration reducing agent is increased, the practicability is high and the applicable range is wide through controlling the reaction temperature in the process.
Drawings
FIG. 1 is a block diagram of the apparatus of the present invention;
FIG. 2 is a flow chart involved in the present invention;
in the figure: the solid arrows on the flue gas pipeline represent the flow direction of flue gas, the hollow arrows on the dotted line and the dotted line represent the signal direction, the 1-NOx detection and signal feedback device, the 2- (GGH) heat exchanger, the 3-temperature detection and signal feedback device, the 4-gas afterburning device, the 5-ammonia injection device, the 6-ammonia storage tank, the 7-static mixer, the 8-catalyst bed layer, the 9-SCR reactor, the 10-electric heater, the 11-induced draft fan and the 12-chimney are arranged on the flue gas pipeline.
Detailed Description
According to the low-temperature SCR denitration device, flue gas is subjected to heat exchange and temperature rise through the (GGH) heat exchanger 2, then denitration and purification are carried out through the SCR reactor 9, and the flue gas is discharged through the chimney 12. The ammonia gas preparation and injection device of the device comprises a denitration reducing agent storage device, namely an ammonia water storage tank 6, a reducing agent preparation, conveying and injection device, namely an ammonia injection device 5, a flue gas detection and (information) feedback device (a NOx detection and signal feedback device 1 and a temperature detection and signal feedback device 3) and a flue gas afterburning device (namely a fuel gas afterburning device) 4.
The GGH heat exchanger 2 is a plate heat exchanger, heat exchange fins of the plate heat exchanger adopt SS304 and SMO254, and the whole equipment comprises main components such as a heat exchange core body module, a self-supporting frame, hot side flue gas and cold side flue gas inlet and outlet reducing parts.
The reducing agent adopts 20% concentrated ammonia water as a raw material, prepares ammonia gas through evaporation, then dilutes the ammonia gas to 5% safe concentration through a dilution fan, and sprays the ammonia gas into a flue gas pipeline through an ammonia spraying device 5 to be mixed with flue gas.
The flue gas after-burning device 4 adopts a gas preheater device, and utilizes natural gas or coke oven gas and the like as fuel to heat the flue gas to the denitration reaction temperature. The operation of the flue gas preheater (namely a gas preheater device) is controlled by the temperature detection and feedback control of the flue gas at the outlet of the GGH heat exchanger 2, so that the temperature of the heated flue gas is controlled (about 200 ℃) in a low-temperature denitration reaction temperature range.
The SCR reactor 9 basically comprises a catalyst bed layer (3 layers), a static mixer 7, a soot blower and other devices, wherein the static mixer 7 is arranged at the front end of the catalyst bed layer.
Preferably, the temperature detection that sets up is connected with the electric heater 10 of signal feedback ware 3 and SCR reactor 9 bottom, need not to set up temperature-detecting device again like this, can in time mend heat to the SCR reactor 9 body for flue gas temperature crosses low influence denitration efficiency and system operation in preventing SCR reactor 9.
The low-temperature flue gas is firstly heated by a heat exchanger 2 (namely a plate heat exchanger), then is further heated by a gas afterburning device 4 to reach a catalyst reaction temperature range in an SCR (selective catalytic reduction) reactor 9, ammonia gas is prepared by using concentrated ammonia water stored in an ammonia water storage tank 6 as a raw material, the ammonia gas is injected into the flue gas heated by the gas (heating) afterburning by an ammonia injection device 5, the flue gas and the ammonia gas are fully mixed by a static mixer 7 and then enter a catalyst (bed) layer 8 in the flowing process of a flue, and the ammonia gas and nitrogen oxides in the flue gas are subjected to redox reaction to generate nontoxic and harmless N under the catalytic reaction of the catalyst in the catalyst process2And H2O, thereby removing nitrogen oxides and purifying the flue gas.
The device and the process have the advantages that the denitration efficiency is improved, the utilization rate of the denitration reducing agent is increased through controlling the reaction temperature in the process, the practicability is high, and the applicable range is wide.
This denitrification facility has two technology main points:
(1) selecting a low-temperature SCR denitration catalyst, wherein the reaction temperature of the catalyst is 180-;
(2) the horizontal structure design of SCR (denitration) reactor, the flue gas is the horizontal direction and flows, sets up ammonia cigarette mixing section and catalyst reaction section in SCR (denitration) reactor.
The utility model relates to a low-temperature SCR denitration device for waste gas of nonferrous metal Kaldo furnace smelting, which mainly comprises the following components: the device comprises a (GGH) heat exchanger, a fuel gas (heating) afterburning device, an ammonia gas preparation and injection device, an SCR reactor and a flue gas detection and feedback device.
The process comprises the steps of heating low-temperature flue gas to a certain temperature through a heat exchanger, heating the low-temperature flue gas to a catalyst reaction activity temperature range (180-200 ℃), detecting a feedback signal according to the concentration of nitrogen oxides in the inlet flue gas, controlling the injection amount of a reducing agent (ammonia gas) to prepare ammonia and spraying the ammonia, fully and uniformly mixing the ammonia-sprayed flue gas through a static mixer, and then feeding the mixed flue gas into a catalyst layer of an SCR reactor to perform denitration reaction. The SCR reactor mainly comprises a flue gas mixing section (namely an ammonia-flue mixing section which comprises a plurality of static mixers), a catalyst (bed) layer, a rake type soot blower and the like. The catalyst is low temperature vanadium-titanium based catalyst with active reaction temperature of 200 ℃.
The heat exchanger is positioned at the front end of the system and aims to fully utilize the waste heat of the clean flue gas after SCR denitration reaction and raise the temperature of the raw flue gas to 170 ℃.
The gas (heating) afterburning device utilizes natural gas as fuel, and the gas is sprayed into a flue gas pipeline through a hot blast stove or directly for afterburning and heating, so that the temperature of the flue gas is further raised to 200 ℃ to reach the reaction activity temperature range of the low-temperature catalyst.
And the ammonia spraying device is positioned behind the smoke afterburning device, ammonia gas is prepared by using ammonia water or urea with the concentration of 20%, the ammonia gas is diluted to the range of 5% safe concentration by using the air extracted by the dilution fan, and the ammonia gas is sprayed into the flue through an ammonia gas nozzle. The ammonia injection amount is controlled accurately mainly through NOx detection and feedback signals of inlet flue gas.
As a preferred technical scheme of the utility model, the SCR reactor adopts a special structural design and is characterized in that a horizontal denitration reactor body is adopted, and the SCR reactor consists of a flue gas mixing section and a catalytic reaction section without intervals. The catalytic reaction section is provided with 3 catalyst (bed) layers; the flue gas mixing section is formed by 2-3 static mixers, and flue gas is uniformly mixed by the mixing section and then enters a catalyst (bed) layer for denitration reaction. The flow speed of the flue gas in the (SCR) reactor is 1-2m/s, and the residence time is 4-5 s. The catalyst has 3 layers (2+1 arrangement, a reserved layer is arranged), and the operating temperature of the catalyst is 200 ℃.
As a preferred technical scheme of the utility model, the front end of each layer of catalyst (bed layer) is provided with a rake type ash remover, and ash blowing is started periodically to remove the smoke dust scattered in the catalyst holes.
As a preferred technical scheme of the utility model, an electric heater is arranged on the outer side of the lower part of the horizontal denitration reactor body of the (SCR) reactor and used for system heat compensation, and a heat tracing device can be started to perform flue gas heat compensation when the temperature of flue gas in the SCR reactor is low according to the feedback of a temperature detection signal in a cabin body of the (SCR) reactor.
Specifically, the process of the device comprises the following steps:
the inlet low-temperature flue gas (about 60 ℃) firstly enters a heat exchanger 2 to exchange heat with the purified high-temperature flue gas (200 ℃), the temperature is raised to 170 ℃, then the flue gas is further heated by a gas afterburning device 4, the heating amount is controlled by a temperature detection and signal feedback device 3, the 170 ℃ raw flue gas is heated to a temperature slightly higher than the SCR catalytic reaction temperature (200 ℃) to about 210 ℃, and then the denitration reducing agent is metered and sprayed by an ammonia spraying device 5;
the denitration reducing agent is prepared by evaporating and diluting 20% ammonia water, the 20% ammonia water is stored in an ammonia water storage tank 6, the concentrated ammonia water is evaporated by steam and diluted into 5% ammonia gas by a dilution fan, and then the 5% ammonia gas is sprayed into a flue gas pipeline to be mixed with flue gas through an ammonia gas spray gun of an ammonia gas spraying device 5 under the accurate metering control of a NOx detection and signal feedback device 1, and at the moment, the temperature of the flue gas is reduced to a catalytic reaction temperature range of about 200 ℃ due to the mixing of the ammonia gas.
The flue gas after ammonia spraying enters a horizontal denitration reactor body of an SCR reactor 9, the flue gas firstly flows through a mixing section consisting of 2-3 static mixers 7 to be fully mixed, then enters a catalyst (bed) layer 8, and nitrogen oxides and ammonia gas in the flue gas in the catalyst are subjected to catalytic reduction reaction to generate N2And H2O, removal of NO and NO2And the nitrogen oxides are obtained by the following main reaction chemical equation:
4NH3+4NO+O2→4N2+6H2O
4NH3+2NO2+O2→3N2+6H2O
the (rake) ash remover arranged at the front end of the catalyst is periodically opened to remove dust accumulated on the surface of the catalyst. In order to prevent the temperature of the ash deposition part at the bottom of the SCR reactor 9 from decreasing, an electric heater 10 at the lower part of the reactor body is started to supplement heat and raise the temperature in time when the temperature of the flue gas is reduced to be out of the range of the denitration reaction interval;
the horizontal denitration reactor body of the SCR reactor 9 is provided with an inspection manhole which is used as a passage for personnel and materials when equipment inside the reactor body is inspected or a catalyst is replaced. The valve plate is arranged at the bottom of the ash deposition groove at the lower part of the device body, and can be manually overhauled or cleaned.
The temperature of the flue gas purified by the denitration reaction is 200 ℃, in order to fully utilize the waste heat of the flue gas and save energy, the clean flue gas with the temperature of 200 ℃ is introduced into the heat exchanger 2, the temperature of the heat exchange raw flue gas is used for increasing the temperature of the heat exchange raw flue gas, the temperature of the clean flue gas discharged from the (GGH) heat exchanger 2 is reduced to about 90 ℃, and finally the clean flue gas is discharged through a chimney 12 under the action of the induced draft fan 11.
Because the uniform distribution of the air flow plays a vital role in denitration, the device adopts a Computational Fluid Dynamics (CFD) method to carry out numerical simulation optimization design on the device.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (9)
1. A low-temperature SCR denitration device for waste gas generated in smelting of a nonferrous metal Kaldo furnace is characterized by comprising a heat exchanger (2), a fuel gas afterburning device (4), an ammonia gas preparation and injection device and an SCR reactor (9), which are sequentially arranged from the direction of flue gas entering; the smoke detection and feedback device is arranged on the smoke inlet pipeline;
the SCR reactor (9) comprises a horizontal denitration reactor body, an ammonia-smoke mixing section and a catalytic reaction section are sequentially arranged in the horizontal denitration reactor body from the direction of a smoke inlet, the ammonia-smoke mixing section comprises a plurality of static mixers (7) which are sequentially arranged from the direction of the smoke inlet, and the catalytic reaction section comprises a plurality of catalyst bed layers (8) which are sequentially arranged from the direction of the smoke inlet;
an electric heater (10) is arranged on the outer side of the lower part of the horizontal denitration reactor body of the SCR reactor (9).
2. The low-temperature SCR denitration device for waste gas from nonferrous metal Kaldo furnace smelting according to claim 1, characterized in that the flue gas outlet direction of the SCR reactor (9) is connected with the heat exchanger (2), the induced draft fan (11) and the chimney (12) in sequence.
3. The low-temperature SCR denitration device for waste gas from nonferrous metal Kaldo furnace smelting according to claim 1 or 2, wherein the ammonia gas preparation and injection device comprises an ammonia injection device (5) and an ammonia water storage tank (6) connected to the ammonia injection device (5).
4. The low-temperature SCR denitration device of waste gas from nonferrous metal Kaldo furnace smelting according to claim 1 or 2, wherein the flue gas detection and feedback device comprises a NOx detection and signal feedback device (1) and a temperature detection and signal feedback device (3); the electric heater (10) is connected with a temperature detection device.
5. The low-temperature SCR denitration device for waste gas from non-ferrous metal Kaldo furnace smelting according to claim 4, characterized in that the temperature detection device is a temperature detection and signal feedback device (3).
6. The low-temperature SCR denitration device for waste gas from non-ferrous metal Kaldo furnace smelting according to claim 3, characterized in that the catalytic reaction section is provided with 3 catalyst beds (8); the flue gas mixing section consists of 2-3 static mixers.
7. The low-temperature SCR denitration device for waste gas from nonferrous metal Kaldo furnace smelting according to claim 5, characterized in that a soot blower is arranged at the front end of each catalyst bed (8) in the SCR reactor (9).
8. The low-temperature SCR denitration device for waste gas from nonferrous metal Kaldo furnace smelting according to claim 1 or 2, characterized in that the flue gas inlet pipe of the SCR reactor (9) is further provided with a heat tracing device.
9. The low-temperature SCR denitration device for waste gas from nonferrous metal Kaldo furnace smelting according to claim 1 or 2, characterized in that the heat exchanger (2) is a plate heat exchanger, the heat exchange fins of the plate heat exchanger are SS304 and SMO254, and the plate heat exchanger is composed of a heat exchange core module, a self-supporting frame, hot side flue gas and cold side flue gas inlet and outlet variable diameter parts; the gas afterburning device (4) is a gas preheater device; a manhole is arranged on a horizontal denitration reactor body of the SCR reactor (9), and a valve plate is arranged at the bottom of a dust collecting groove at the lower part of the horizontal denitration reactor body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121029331.XU CN216295771U (en) | 2021-05-13 | 2021-05-13 | Low-temperature SCR denitration device for waste gas generated in smelting of nonferrous metal Kaldo furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121029331.XU CN216295771U (en) | 2021-05-13 | 2021-05-13 | Low-temperature SCR denitration device for waste gas generated in smelting of nonferrous metal Kaldo furnace |
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| Publication Number | Publication Date |
|---|---|
| CN216295771U true CN216295771U (en) | 2022-04-15 |
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| CN113209823A (en) * | 2021-05-13 | 2021-08-06 | 安徽威达环保科技股份有限公司 | Low-temperature SCR denitration device and process for waste gas from nonferrous metal Kaldo furnace smelting |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113209823A (en) * | 2021-05-13 | 2021-08-06 | 安徽威达环保科技股份有限公司 | Low-temperature SCR denitration device and process for waste gas from nonferrous metal Kaldo furnace smelting |
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