CN109603530A - A kind of hot exhaust gas is interior to recycle composite purifying process - Google Patents

A kind of hot exhaust gas is interior to recycle composite purifying process Download PDF

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Publication number
CN109603530A
CN109603530A CN201910003291.2A CN201910003291A CN109603530A CN 109603530 A CN109603530 A CN 109603530A CN 201910003291 A CN201910003291 A CN 201910003291A CN 109603530 A CN109603530 A CN 109603530A
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CN
China
Prior art keywords
exhaust gas
hot exhaust
air
introduced machine
heat
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201910003291.2A
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Chinese (zh)
Inventor
何向阳
刘凯
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FEATURE-TEC (WUXI) FILTRATION TECHNOLOGY Co Ltd
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FEATURE-TEC (WUXI) FILTRATION TECHNOLOGY Co Ltd
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Application filed by FEATURE-TEC (WUXI) FILTRATION TECHNOLOGY Co Ltd filed Critical FEATURE-TEC (WUXI) FILTRATION TECHNOLOGY Co Ltd
Priority to CN201910003291.2A priority Critical patent/CN109603530A/en
Publication of CN109603530A publication Critical patent/CN109603530A/en
Pending legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/74General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86Catalytic processes
    • B01D53/8621Removing nitrogen compounds
    • B01D53/8625Nitrogen oxides
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D46/00Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/24Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/74General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86Catalytic processes
    • B01D53/8678Removing components of undefined structure
    • B01D53/8687Organic components
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J15/00Arrangements of devices for treating smoke or fumes
    • F23J15/006Layout of treatment plant
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D17/00Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
    • F27D17/004Systems for reclaiming waste heat
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D17/00Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
    • F27D17/008Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases cleaning gases
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/70Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
    • B01D2257/708Volatile organic compounds V.O.C.'s
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J2215/00Preventing emissions
    • F23J2215/10Nitrogen; Compounds thereof
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J2217/00Intercepting solids
    • F23J2217/10Intercepting solids by filters
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J2219/00Treatment devices
    • F23J2219/10Catalytic reduction devices
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/25Process efficiency

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  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)

Abstract

The present invention provides recycle composite purifying process in a kind of hot exhaust gas, comprising the following steps: hot exhaust gas is delivered to clean unit by the first air-introduced machine and handles;A part is delivered to heat exchanger processing by the second air-introduced machine in purified hot exhaust gas;Treated that hot exhaust gas is back to that the first air-introduced machine is again introduced into clean unit processing for heat exchanger;Another part, which is heated or condensed through over-heat-exchanger, in purified hot exhaust gas is delivered to smoke stack emission.Filter element is equipped in clean unit, catalyst loading device and thermal reactor, the pernicious gases such as the nitrogen oxides in hot exhaust gas can be removed, purified portion gas is recycled in purification device the concentration for reducing gas to be processed, extend the service life of purification device, and efficiently use purified gas heat, chimney is discharged in gas through over-heat-exchanger, realization disappears contour painting energy, entire Process Route Planning is brief, heat energy recycling, hot exhaust gas purification device overall structure occupied area is small, saves the process cost.

Description

A kind of hot exhaust gas is interior to recycle composite purifying process
Technical field
The present invention relates to recycle composite purifying process in technical field of waste gas treatment more particularly to a kind of hot exhaust gas.
Background technique
The scheme for having a large amount of discharge units to reduce pollutant concentration in hot exhaust gas by adding fresh air at this stage carries out The processing of hot exhaust gas needs to increase energy consumption when adding fresh air, while fresh although program contaminant reducing concentration Air is introduced into processing unit, will cause secondary pollution, and mixing air discharges after purified treatment, increases purification device Load.Equipment energy consumption will increase using this process hot exhaust gas, influence the service life of purification device, reduce purification effect Rate, treated, and the total amount of pollutant is not reduced, and is not contributed to the reduction of the total amount of pollutant in environment.
In view of this, it is necessary to hot exhaust gas treatment process in the prior art be improved, to solve the above problems.
Summary of the invention
It is an object of the invention to disclose in a kind of hot exhaust gas to recycle composite purifying process, hot exhaust gas is carried out at purification Reason, after over-heat-exchanger exchanges heat, part of gas, which is again introduced into purification device, reduces gas concentration in device, improves net Change efficiency, extends service using life, achieve the effect that energy-efficient.
To achieve the above object, the present invention provides recycle composite purifying process in a kind of hot exhaust gas, which is characterized in that packet Include following steps:
(1) hot exhaust gas is delivered to clean unit processing by the first air-introduced machine;
(2) in purified hot exhaust gas a part by the second air-introduced machine be delivered to heat exchanger processing;
(3) treated that hot exhaust gas is back to that the first air-introduced machine is again introduced into clean unit processing for heat exchanger;
(4) another part is heated through over-heat-exchanger in purified hot exhaust gas or condensation is delivered to smoke stack emission.
In some embodiments, the ratio of hot exhaust gas is 0.05~1 in step (2) and step (4).
In some embodiments, first air-introduced machine and the second air-introduced machine boost range are 1~60KPa.
In some embodiments, the clean unit includes filter element, catalyst loading device and thermal reactor.
In some embodiments, the filter element is ceramic fibre chimney filter.
In some embodiments, the thermal reactor temperature is 120~1800 DEG C.
In some embodiments, the heat exchanger heating temperature is 120~900 DEG C or condensation temperature is 40~80 ℃。
Compared with prior art, the beneficial effects of the present invention are: it is anti-equipped with catalyst loading device and heat in clean unit It answers device to carry, the pernicious gases such as the nitrogen oxides in hot exhaust gas can be removed, purified portion gas is recycled to drop in purification device The concentration of low gas to be processed, extends the service life of purification device, and efficiently uses purified gas heat, and energy conservation is high Chimney is discharged in effect, the gas through over-heat-exchanger, realizes the contour painting energy that disappears.
Detailed description of the invention
Fig. 1, which is that a kind of hot exhaust gas is interior shown in the present invention, recycles composite purifying process schematic diagram.
Specific embodiment
The present invention is described in detail for each embodiment shown in reference to the accompanying drawing, but it should be stated that, these Embodiment is not limitation of the present invention, those of ordinary skill in the art according to these embodiments made by function, method, Or equivalent transformation or substitution in structure, all belong to the scope of protection of the present invention within.
Embodiment 1:
Present embodiment discloses recycle composite purifying process in a kind of hot exhaust gas as shown in Figure 1, comprising the following steps:
It (1) is 200mg/m containing ammonia nitrogen concentration3, flow 10000m3300 DEG C of hot exhaust gas of/h are delivered to by the first air-introduced machine Clean unit processing, clean unit is interior to be equipped with filter element, catalyst loading device and thermal reactor, filters by clean unit Large granular impurity in hot exhaust gas is removed, and to the ammonia nitrogen in flue gas, VOC processing under high temperature and catalyst action, wherein filtering Element is ceramic fibre chimney filter, and thermal reactor temperature is 120 DEG C;
(2) purified hot exhaust gas temperature is down to 120 DEG C, and a portion hot exhaust gas is by adjusting after valve regulating flow by second Air-introduced machine is delivered to heat exchanger processing and is warming up to 300 DEG C;
(3) treated that hot exhaust gas is back to that the first air-introduced machine is again introduced into clean unit processing for heat exchanger, and purification is single at this time Ammonia nitrogen concentration is reduced to 80mg/m3 in member, again passes by clean unit circular treatment;
(4) in purified hot exhaust gas another part through over-heat-exchanger be heated to 400 DEG C realize disappear it is white and be delivered to chimney row It puts.
Wherein, hot exhaust gas by adjusting valve regulation ratio is 0.05 in step (2) and step (4), first air-introduced machine It is 1KPa with the second air-introduced machine boost range.
Embodiment 2:
Present embodiment discloses recycle composite purifying process in a kind of hot exhaust gas as shown in Figure 1, comprising the following steps:
It (1) is 200mg/m containing ammonia nitrogen concentration3, flow 10000m3300 DEG C of hot exhaust gas of/h are delivered to by the first air-introduced machine Clean unit processing, clean unit is interior to be equipped with filter element, catalyst loading device and thermal reactor, filters by clean unit Large granular impurity in hot exhaust gas is removed, and to the ammonia nitrogen in flue gas, VOC processing under high temperature and catalyst action, wherein filtering Element is ceramic fibre chimney filter, and thermal reactor temperature is 800 DEG C;
(2) purified hot exhaust gas temperature rises to 800 DEG C, and a portion hot exhaust gas is by adjusting after valve regulating flow by second Air-introduced machine is delivered to heat exchanger processing and is cooled to 300 DEG C;
(3) treated that hot exhaust gas is back to that the first air-introduced machine is again introduced into clean unit processing for heat exchanger, and purification is single at this time Ammonia nitrogen concentration is reduced to 80mg/m3 in member, again passes by clean unit circular treatment;
(4) another part is cooled to 400 DEG C through over-heat-exchanger and is delivered to smoke stack emission in purified hot exhaust gas.
Wherein, hot exhaust gas by adjusting valve regulation ratio is 0.5 in step (2) and step (4), first air-introduced machine and Second air-introduced machine boost range is 20KPa.
Embodiment 3:
Present embodiment discloses recycle composite purifying process in a kind of hot exhaust gas as shown in Figure 1, comprising the following steps:
It (1) is 200mg/m containing ammonia nitrogen concentration3, flow 10000m3300 DEG C of hot exhaust gas of/h are delivered to by the first air-introduced machine Clean unit processing, clean unit is interior to be equipped with filter element, catalyst loading device and thermal reactor, filters by clean unit Large granular impurity in hot exhaust gas is removed, and to the ammonia nitrogen in flue gas, VOC processing under high temperature and catalyst action, wherein filtering Element is ceramic fibre chimney filter, and thermal reactor temperature is 1800 DEG C;
(2) purified hot exhaust gas temperature rises to 1800 DEG C, and a portion hot exhaust gas is by adjusting after valve regulating flow by the Two air-introduced machines are delivered to heat exchanger processing and are cooled to 300 DEG C;
(3) treated that hot exhaust gas is back to that the first air-introduced machine is again introduced into clean unit processing for heat exchanger, and purification is single at this time Ammonia nitrogen concentration is reduced to 80mg/m3 in member, again passes by clean unit circular treatment;
(4) another part through over-heat-exchanger is cooled to 40 DEG C in purified hot exhaust gas, since temperature reduces recycling condensed water It recycles spare.
Wherein, hot exhaust gas by adjusting valve regulation ratio is 1 in step (2) and step (4), first air-introduced machine and the Two air-introduced machine boost ranges are 60KPa.
Ceramic fibre chimney filter can coat catalyst, substitution catalysis on its surface according to the technological requirements in above embodiments Agent loading device optimizes clean unit overall structure.
The series of detailed descriptions listed above only for feasible embodiment of the invention specifically Protection scope bright, that they are not intended to limit the invention, it is all without departing from equivalent implementations made by technical spirit of the present invention Or change should all be included in the protection scope of the present invention.
In addition, it should be understood that although this specification is described in terms of embodiments, but not each embodiment is only wrapped Containing an independent technical solution, this description of the specification is merely for the sake of clarity, and those skilled in the art should It considers the specification as a whole, the technical solutions in the various embodiments may also be suitably combined, forms those skilled in the art The other embodiments being understood that.

Claims (7)

1. recycling composite purifying process in a kind of hot exhaust gas, which comprises the following steps:
(1) hot exhaust gas is delivered to clean unit processing by the first air-introduced machine;
(2) in purified hot exhaust gas a part by the second air-introduced machine be delivered to heat exchanger processing;
(3) treated that hot exhaust gas is back to that the first air-introduced machine is again introduced into clean unit processing for heat exchanger;
(4) another part is heated through over-heat-exchanger in purified hot exhaust gas or condensation is delivered to smoke stack emission.
2. recycling composite purifying process in hot exhaust gas according to claim 1, which is characterized in that step (2) and step (4) The ratio of middle hot exhaust gas is 0.05~1.
3. recycling composite purifying process in hot exhaust gas according to claim 1, which is characterized in that first air-introduced machine and Second air-introduced machine boost range is 1~60KPa.
4. recycling composite purifying process in hot exhaust gas according to claim 1, which is characterized in that the clean unit includes Filter element, catalyst loading device and thermal reactor.
5. recycling composite purifying process in hot exhaust gas according to claim 4, which is characterized in that the filter element is pottery Porcelain fiber chimney filter.
6. recycling composite purifying process in hot exhaust gas according to claim 4, which is characterized in that the thermal reactor temperature It is 120~1800 DEG C.
7. recycling composite purifying process in hot exhaust gas according to claim 1, which is characterized in that the heat exchanger heating Temperature is 120~900 DEG C or condensation temperature is 40~80 DEG C.
CN201910003291.2A 2019-01-03 2019-01-03 A kind of hot exhaust gas is interior to recycle composite purifying process Pending CN109603530A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112391210A (en) * 2020-11-17 2021-02-23 滨州中科催化技术有限公司 Coke oven gas purification system

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Publication number Priority date Publication date Assignee Title
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JP2017172911A (en) * 2016-03-25 2017-09-28 三菱日立パワーシステムズ株式会社 Thermal power generation system and control method of thermal power generation system
CN108050850A (en) * 2017-11-02 2018-05-18 武汉东晟捷能科技有限公司 A kind of yellow phosphoric tail gas boiler flue gas purification system and purification method
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CN108339386A (en) * 2018-04-19 2018-07-31 武汉致衡环境安全工程技术有限公司 A kind of system improving SCR denitration reactor inlet temperatures using flue gas recirculation

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CN101439260A (en) * 2008-12-04 2009-05-27 浙江大学 System for removing nitrous oxides in low-temperature flue gas and technique thereof
JP2017172911A (en) * 2016-03-25 2017-09-28 三菱日立パワーシステムズ株式会社 Thermal power generation system and control method of thermal power generation system
CN108050850A (en) * 2017-11-02 2018-05-18 武汉东晟捷能科技有限公司 A kind of yellow phosphoric tail gas boiler flue gas purification system and purification method
CN108317531A (en) * 2018-01-05 2018-07-24 苏州浩长空环保科技有限公司 A kind of smoke comprehensive processing desulphurization system and its desulfurization fume processing method
CN108339386A (en) * 2018-04-19 2018-07-31 武汉致衡环境安全工程技术有限公司 A kind of system improving SCR denitration reactor inlet temperatures using flue gas recirculation

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112391210A (en) * 2020-11-17 2021-02-23 滨州中科催化技术有限公司 Coke oven gas purification system

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Application publication date: 20190412