CN203916464U - A kind of eddy current opposite-flushing type gas mixer being arranged in gas passage - Google Patents
A kind of eddy current opposite-flushing type gas mixer being arranged in gas passage Download PDFInfo
- Publication number
- CN203916464U CN203916464U CN201420096293.3U CN201420096293U CN203916464U CN 203916464 U CN203916464 U CN 203916464U CN 201420096293 U CN201420096293 U CN 201420096293U CN 203916464 U CN203916464 U CN 203916464U
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- China
- Prior art keywords
- guiding device
- gas
- flow
- eddy current
- flue gas
- 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.)
- Expired - Lifetime
Links
- 238000011010 flushing procedure Methods 0.000 title claims abstract description 16
- 239000007789 gas Substances 0.000 claims abstract description 53
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 48
- 239000003546 flue gas Substances 0.000 claims abstract description 48
- 235000003283 Pachira macrocarpa Nutrition 0.000 claims abstract description 12
- 241001083492 Trapa Species 0.000 claims abstract description 12
- 235000014364 Trapa natans Nutrition 0.000 claims abstract description 12
- 235000009165 saligot Nutrition 0.000 claims abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000000779 smoke Substances 0.000 claims abstract description 11
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 4
- 238000002347 injection Methods 0.000 claims description 11
- 239000007924 injection Substances 0.000 claims description 11
- 239000007921 spray Substances 0.000 claims description 8
- 230000001154 acute effect Effects 0.000 claims description 3
- 239000003638 chemical reducing agent Substances 0.000 abstract description 27
- 238000010276 construction Methods 0.000 abstract description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 14
- 239000003054 catalyst Substances 0.000 description 9
- 229910021529 ammonia Inorganic materials 0.000 description 7
- 230000009466 transformation Effects 0.000 description 6
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000006722 reduction reaction Methods 0.000 description 3
- 230000003068 static effect Effects 0.000 description 3
- 238000010531 catalytic reduction reaction Methods 0.000 description 2
- 235000019994 cava Nutrition 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 210000000003 hoof Anatomy 0.000 description 2
- 230000002787 reinforcement Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 239000010908 plant waste Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000010977 unit operation Methods 0.000 description 1
Abstract
The utility model discloses a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage, it is characterized in that, comprises guiding device, nozzle, pipeline, flue gas disturbing flow device, bracing or strutting arrangement; Described pipeline penetrates flue sidewall and continues and extends; Described nozzle is arranged on one end of pipeline bearing of trend; The jet of described nozzle ejection is ejected on described guiding device; Described flue gas disturbing flow device is arranged on the smoke gas flow upstream position of relatively described guiding device; Described flue gas disturbing flow device matches with guiding device, makes smoke gas flow after described flue gas disturbing flow device, form water chestnut eddy current and wraps the air-flow forming via guiding device water conservancy diversion.Utilize the special construction of electric hybrid module to confuse flow field, smoke gas flow is through surface plate, form horse shoe vortex at the surface plate back side, and reducing agent forms jet from spout ejection, jet guides through reducing agent water diversion part, form and liquidate with the horse shoe vortex of flue gas, the supreme reduction air-flow that wraps downwards of horse shoe vortex, forms both mixing.
Description
Technical field
The utility model relates to a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage, belongs to statical mixer of gases field.
Background technology
Selective catalytic reduction (SCR) is current industrial most important denitration technology.It is widely used in the fields such as boats and ships, motor vehicle, thermal power plant, and the burning of engine or boiler produces nitrogen oxide NO
x, these gas dischargings, in atmosphere, can bring the harm such as acid rain, photochemical fog, Ozone Layer Depletion, affect the mankind's life.In recent years atmosphere pollutants emission standards day stricter, aspect thermal power plant, domestic requirements carries out retrofit work to the active service unit that denitration device is not installed, and between economizer and air preheater, installs SCR system additional.Due to the restriction in transformation space and place, transformation can cause flue gas and reducing agent to mix distance not, makes catalyst upper strata NH
3/ NO
xskewness.The inhomogeneous meeting of concentration field causes out of stock decrease in efficiency, and the escaping of ammonia rate increases, and affects the feature of environmental protection and the security of power plant, for unit operation brings problem.Under the not high operating mode of the denitration efficiencies such as burning deflection, boiler at low load operation, the efficient meaning of mixing of reducing agent and flue gas is more outstanding especially.
In SCR system, static mixer mixes and has the most directly impact ammonia nitrogen.In Turbulent Flow Field, blender utilizes self special structure, makes former flue gas produce deflection or form the disturbances such as eddy current, eddy flow to improve mixing intensity, to reduce to mix distance.And be accompanied by efficient mixing, and system pressure drop also can raise, and causes air-introduced machine power consumption to rise, and therefore designs efficient blender, and reasonably balanced economy and feature of environmental protection problem are current important problems.
Summary of the invention
Goal of the invention: the purpose of this utility model is to provide a kind of eddy current opposite-flushing type gas mixer that utilizes gas good mixing effect.
Technical scheme: a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage described in the utility model, comprises guiding device, nozzle, pipeline, flue gas disturbing flow device, bracing or strutting arrangement; Described pipeline penetrates flue sidewall and continues and extends; Described nozzle is arranged on one end of pipeline bearing of trend; The jet of described nozzle ejection is ejected on described guiding device; Described flue gas disturbing flow device is arranged on the smoke gas flow upstream position of relatively described guiding device; Described flue gas disturbing flow device matches with guiding device, makes smoke gas flow after described flue gas disturbing flow device, form water chestnut eddy current and wraps the air-flow forming via guiding device water conservancy diversion.
When so-called water chestnut eddy current refers to flue gas and skims over flue gas disturbing flow device outward, there is the separation in boundary layer, the shape of a hoof vortex structure of formation.
Further, spray along the tangential direction of this streamline of water chestnut eddy current from the inside of described water chestnut eddy current and roughly through the air-flow of guiding device water conservancy diversion.
Further, as shown in Figure 1.Flue gas disturbing flow device is a circular flat board, and described guiding device Wei Die center is with protruding dish-shaped guiding device, and described projection is pointed to nozzle and contrary with injection direction in nozzle; The indent direction of described dish-shaped guiding device dish face is contrary with the protrusion direction of described projection.Dish in this device is the dish type that has surrounding edge, to size indefinite, coils central dish face and caves inward with respect to surrounding edge, and the direction of pointing to central dish face by surrounding edge one side perpendicular to central dish face is indent direction.
Further, described bracing or strutting arrangement is that guiding device is fixed on to the some support bars on flue gas disturbing flow device.
Further, described nozzle spray direction is perpendicular to circular flat board plane.
Further, in described circular flat board plane and gas passage, between gas flow direction, angle is acute angle.
The utility model compared with prior art, its beneficial effect is: utilized the special construction of electric hybrid module to confuse flow field, smoke gas flow is through surface plate, form horse shoe vortex at the surface plate back side, and reducing agent forms jet from spout ejection, jet guides through reducing agent water diversion part, form and liquidate with the horse shoe vortex of flue gas, the supreme reduction air-flow that wraps downwards of horse shoe vortex, form both strong mixing, effectively overcome the SCR of power plant transformation limited space and mix the problem that distance is not enough, in reducing the escaping of ammonia rate, improved denitration efficiency.In addition, because nozzle and electric hybrid module set become a model, the degree of depth of arrangement of components is reduced, further extended the mixing distance of flue gas and reducing agent.
Brief description of the drawings
Fig. 1 is a kind of eddy current opposite-flushing type gas mixer schematic diagram being arranged in gas passage described in the utility model.
Detailed description of the invention
Below technical solutions of the utility model are elaborated, but protection domain of the present utility model is not limited to described embodiment.
Embodiment:
Embodiment of the present utility model be for existing thermal power plant unit utilize selective catalytic reduction denitration the effect that gas uniform mixed through this gas mixer of ammonia and power plant waste gas.But the application occasion of the gas mixer of gas mixer of the present utility model and composition thereof is not limited in this, can be applicable to the occasion that needs gas to mix that can be suitable for that those of ordinary skill in the art can expect.Now, gas passage is the flue in thermal power generation field, and walling of flue 5 as shown in Figure 1.
In the present embodiment, be arranged on the eddy current opposite-flushing type gas mixer in gas passage, arrange as shown in Figure 1, comprise guiding device 1, nozzle 10, pipeline 6, flue gas disturbing flow device 9, bracing or strutting arrangement 3; Described pipeline 6 penetrates flue sidewall and continues and extends; Described nozzle 10 is arranged on one end of pipeline 6 bearing of trends; The jet that described nozzle 10 sprays is ejected on described guiding device 1; Described flue gas disturbing flow device 9 is arranged on the smoke gas flow upstream position of relatively described guiding device 1; Described flue gas disturbing flow device 9 matches with guiding device 1, makes smoke gas flow after described flue gas disturbing flow device 9, form water chestnut eddy current and wraps the air-flow forming via guiding device 1 water conservancy diversion.
When so-called water chestnut eddy current refers to flue gas and skims over flue gas disturbing flow device outward, there is the separation in boundary layer, the shape of a hoof vortex structure of formation.
Air-flow through guiding device 1 water conservancy diversion in the present embodiment sprays along the tangential direction of this streamline of water chestnut eddy current from the inside of described water chestnut eddy current and roughly.
Flue gas disturbing flow device 9 in the present embodiment is a circular flat board, and described guiding device 1 Wei Die center is with protruding dish-shaped guiding device, and described projection is pointed to nozzle 10 and contrary with injection direction in nozzle 10; The indent direction of described dish-shaped guiding device dish face is contrary with the protrusion direction of described projection.Dish in this device is the dish type that has surrounding edge, to size indefinite, coils central dish face and caves inward with respect to surrounding edge, and the direction of pointing to central dish face by surrounding edge one side perpendicular to central dish face is indent direction.
Bracing or strutting arrangement 3 in the present embodiment is for to be fixed on the some support bars on flue gas disturbing flow device 1 by guiding device 1.Nozzle spray direction is perpendicular to circular flat board plane.In circular flat board plane and gas passage, between gas flow direction, angle is acute angle.
The utility model synthesizes an element electric hybrid module and injection of reducing agent injection device, and electric hybrid module is divided into flue gas flow-disturbing part and reducing agent water diversion part, and injection of reducing agent injection device is made up of pipeline and nozzle.Reducing agent pipeline is through flue shell, and nozzle and incoming flow flue gas are angled, and flue gas spoiler is divided into a surface plate, is vertically welded on nozzle, and reducing agent guiding device designs above surface plate, is fixed on surface plate by reinforcement bar support strut.
Described flue gas disturbing flow device 9 is made up of the metallic plate of abrasion-proof corrosion-proof, be welded on nozzle 10, guiding device 1 is made up of special dies, inner face has streamlined, and be fixed on surface plate by support bar, support bar two ends be separately fixed on flue gas disturbing flow device 9 with securing member and guiding device 1 on.
As shown in Figure 1, the utility model synthesizes an element electric hybrid module and injection of reducing agent injection device, and electric hybrid module is divided into flue gas flow-disturbing part and reducing agent water diversion part, and injection of reducing agent injection device is made up of pipeline 6 and nozzle 10.Reducing agent pipeline is through flue shell, flow of flue gas direction in nozzle and flue is angled, and flue gas spoiler is divided into a surface plate, is vertically welded on nozzle, reducing agent guiding device 1 designs above surface plate, is fixed on surface plate by reinforcement bar support strut 3.
Described flue gas disturbing flow device is made up of the metallic plate (the utility model is plectane) of abrasion-proof corrosion-proof, be welded on reductant nozzle, reducing agent guiding device is made up of special dies, inner face has streamlined, and be fixed on surface plate by support bar, support bar two ends are separately fixed on two disturbing flow devices with securing member.
The mixed assembly in flue cross section is divided into several regions, the ability that each region gas mixes is determined by the electric hybrid module in this region, the size in each region is determined by the design size of flue gas disturbing flow device, consider two bursts of liquidate angle and sizes that air-flow is suitable, the size of flue gas disturbing flow device is subject to the impact of reductant nozzle and reducing agent guiding device design size.For each Mixed Zone, adopting eddy current opposite-flushing type SCR blender is to have utilized the special construction of electric hybrid module to confuse flow field, smoke gas flow is through surface plate, form horse shoe vortex at the surface plate back side, and reducing agent forms jet from spout ejection, jet guides through reducing agent water diversion part, form and liquidate with the horse shoe vortex of flue gas, the supreme reduction air-flow that wraps downwards of horse shoe vortex, form both strong mixing, effectively overcome the SCR of power plant transformation limited space and mix the problem that distance is not enough, in reducing the escaping of ammonia rate, improved denitration efficiency.In addition, because nozzle and electric hybrid module set become a device, the degree of depth of arrangement of components is reduced, further extended the mixing distance of flue gas and reducing agent.
When inserted type double-cyclone SCR static mixer real work of the present utility model, situation is as follows:
In SCR system, in reactor, to select to load three layers of honeycombed catalyst, every layer of catalyst is made up of some catalyst modules, and each catalyst module can be divided into again some catalyst fritters.If will improve out of stock efficiency in engineering and reduce the escaping of ammonia rate, must ensure that the ammonia nitrogen on each catalyst module upper strata is than approximate identical, stricter in the situation that, must ensure that the ammonia nitrogen on hole path upper strata in each catalyst is than approximate identical.Due to active service Transformation of Unit limited space, make to spray ammonia cross section to mixing distance deficiency between first floor catalyst upper strata, inner in limited mixing distance, if will ensure the requirement that above-mentioned ammonia nitrogen mixes, static mixer is the means of effectively appealing to efficiently.Adopting eddy current opposite-flushing type SCR blender is to have utilized the special construction of electric hybrid module to confuse flow field, flue gas 1.8 surface plate of flowing through, form horse shoe vortex 4 at the surface plate back side, and reducing agent 7 forms jet from spout ejection, jet impacts guiding device 1 in the starting stage forming, through the special fairshaped guiding function of reducing agent guiding device internal face, the horse shoe vortex formation producing with flue gas stream liquidates, the supreme reduction air-flow 2 that wraps downwards of horse shoe vortex, this effect mutually liquidating and wrap up can cause the strong mixing of two strands of air-flows, effectively overcome the SCR of power plant transformation limited space and mix the problem that distance is not enough, in reducing the escaping of ammonia rate, improve denitration efficiency.In addition, because nozzle and electric hybrid module set become a model, the degree of depth of arrangement of components is reduced, further extended the mixing distance of flue gas and reducing agent.
As mentioned above, although represented and explained the utility model with reference to specific preferred embodiment, it shall not be construed as the restriction to the utility model self.Not departing under the spirit and scope prerequisite of the present utility model of claims definition, can make in the form and details various variations to it.
Claims (6)
1. be arranged on the eddy current opposite-flushing type gas mixer in gas passage, it is characterized in that, comprise guiding device (1), nozzle (10), pipeline (6), flue gas disturbing flow device (9), bracing or strutting arrangement (3); Described pipeline (6) penetrates flue sidewall and continues and extends; Described nozzle (10) is arranged on one end of pipeline (6) bearing of trend; The jet of described nozzle (10) ejection is ejected on described guiding device (1); Described flue gas disturbing flow device (9) is arranged on the smoke gas flow upstream position of relatively described guiding device (1); Described flue gas disturbing flow device (9) matches with guiding device (1), makes smoke gas flow after described flue gas disturbing flow device (9), form water chestnut eddy current and wraps the air-flow forming via guiding device (1) water conservancy diversion.
2. a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage according to claim 1, it is characterized in that, the described air-flow through guiding device (1) water conservancy diversion sprays along the tangential direction of this streamline of water chestnut eddy current from the inside of described water chestnut eddy current and roughly.
3. a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage according to claim 1, it is characterized in that, described flue gas disturbing flow device (9) is a circular flat board, described guiding device (1) Wei Die center is with protruding dish-shaped guiding device, and described projection is pointed to nozzle (10) and contrary with injection direction in nozzle (10); The indent direction of described dish-shaped guiding device dish face is contrary with the protrusion direction of described projection.
4. according to a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage described in claim 1,2 or 3, it is characterized in that, described bracing or strutting arrangement (3) is for to be fixed on the some support bars on flue gas disturbing flow device (1) by guiding device (1).
5. a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage according to claim 3, is characterized in that, described nozzle spray direction is perpendicular to circular flat board plane.
6. a kind of eddy current opposite-flushing type gas mixer being arranged in gas passage according to claim 5, is characterized in that, in described circular flat board plane and gas passage, between gas flow direction, angle is acute angle.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN201420096293.3U CN203916464U (en) | 2014-03-03 | 2014-03-03 | A kind of eddy current opposite-flushing type gas mixer being arranged in gas passage |
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CN201420096293.3U CN203916464U (en) | 2014-03-03 | 2014-03-03 | A kind of eddy current opposite-flushing type gas mixer being arranged in gas passage |
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CN201420096293.3U Expired - Lifetime CN203916464U (en) | 2014-03-03 | 2014-03-03 | A kind of eddy current opposite-flushing type gas mixer being arranged in gas passage |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103816801A (en) * | 2014-03-03 | 2014-05-28 | 东南大学 | Eddy-current opposite-impacting type gas mixer arranged in gas passage |
CN107269364A (en) * | 2016-03-31 | 2017-10-20 | 曼柴油机和涡轮机欧洲股份公司 | Exhausted gas post-processing system and internal combustion engine |
-
2014
- 2014-03-03 CN CN201420096293.3U patent/CN203916464U/en not_active Expired - Lifetime
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103816801A (en) * | 2014-03-03 | 2014-05-28 | 东南大学 | Eddy-current opposite-impacting type gas mixer arranged in gas passage |
CN103816801B (en) * | 2014-03-03 | 2016-01-06 | 东南大学 | A kind of eddy current opposite-flushing type gas mixer be arranged in gas passage |
CN107269364A (en) * | 2016-03-31 | 2017-10-20 | 曼柴油机和涡轮机欧洲股份公司 | Exhausted gas post-processing system and internal combustion engine |
CN107269364B (en) * | 2016-03-31 | 2020-12-08 | 曼恩能源方案有限公司 | Exhaust gas aftertreatment system and internal combustion engine |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
C53 | Correction of patent of invention or patent application | ||
CB03 | Change of inventor or designer information |
Inventor after: Si Fengqi Inventor after: Yu Cong Inventor after: Zhu Zhengxiang Inventor after: Xu Zhigao Inventor before: Si Fengqi Inventor before: Yu Cong Inventor before: Xu Zhigao |
|
COR | Change of bibliographic data |
Free format text: CORRECT: INVENTOR; FROM: SI FENGQI YU CONG XU ZHIGAO TO: SI FENGQI YU CONG ZHU ZHENGXIANG XU ZHIGAO |
|
CX01 | Expiry of patent term |
Granted publication date: 20141105 |
|
CX01 | Expiry of patent term |