CN203833627U - Pyrolysis furnace air sealing device for system for ammonia production by pyrolysis of urea - Google Patents
Pyrolysis furnace air sealing device for system for ammonia production by pyrolysis of urea Download PDFInfo
- Publication number
- CN203833627U CN203833627U CN201420246638.9U CN201420246638U CN203833627U CN 203833627 U CN203833627 U CN 203833627U CN 201420246638 U CN201420246638 U CN 201420246638U CN 203833627 U CN203833627 U CN 203833627U
- Authority
- CN
- China
- Prior art keywords
- pyrolysis oven
- interface
- housing
- compressed air
- air inlet
- 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
- 238000000197 pyrolysis Methods 0.000 title claims abstract description 100
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 38
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 title claims abstract description 25
- 239000004202 carbamide Substances 0.000 title claims abstract description 25
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 19
- 238000007789 sealing Methods 0.000 title abstract description 5
- 238000004519 manufacturing process Methods 0.000 title abstract 2
- 230000008602 contraction Effects 0.000 claims description 16
- 229910001220 stainless steel Inorganic materials 0.000 claims description 4
- 239000010935 stainless steel Substances 0.000 claims description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 abstract description 5
- 229910002092 carbon dioxide Inorganic materials 0.000 abstract 1
- 239000001569 carbon dioxide Substances 0.000 abstract 1
- 238000005516 engineering process Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 239000003546 flue gas Substances 0.000 description 5
- 239000007921 spray Substances 0.000 description 5
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 235000011089 carbon dioxide Nutrition 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 230000036541 health Effects 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000002829 reductive effect Effects 0.000 description 2
- 239000000779 smoke Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- PPBAJDRXASKAGH-UHFFFAOYSA-N azane;urea Chemical compound N.NC(N)=O PPBAJDRXASKAGH-UHFFFAOYSA-N 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
Landscapes
- Exhaust Gas After Treatment (AREA)
Abstract
The utility model discloses a pyrolysis furnace air sealing device for a system for ammonia production by pyrolysis of urea. The device comprises a housing on which an ejector joint, a pyrolysis furnace joint and a compressed air inlet are formed and a drainage sleeve arranged in a housing inner cavity in which the entire compressed air inlet is formed, in a sleeving manner; a plurality of perforation holes are formed in the outer side, close to the pyrolysis furnace joint, around the drainage sleeve; at the compressed air inlet, a clearance extending to the perforation holes is arranged between an outer side wall of the drainage sleeve and an inner side wall of the housing, and the outer edges of one end, close to the clearance, of the plurality of perforation holes are formed into a shrinkage structure along a direction in which the compressed air enters the pyrolysis furnace joint. According to the structure, the drainage sleeve is arranged outside the ejector in a sleeving manner, when the ejector is pulled out, the compressed air is introduced from the compressed air inlet, the compressed air reaches the perforation holes along the clearance, and the high-pressure compressed air is pressed into the pyrolysis furnace joint and thus the problem of leakage of ammonia and carbon dioxide in the pyrolysis furnace is avoided.
Description
Technical field
The utility model relates in urea pyrolysis ammonia system processed, and injector when extracting in pyrolysis oven, for avoiding the pyrolysis oven sealed air device that in pyrolysis oven, gas leak designs, belongs to urea ammonia pyrolysis oven processed sealing equipment technical field.
Background technology
In a large amount of flue gases that industrial fuel burning produces, contain the oxynitride (NOx) of high density, oxynitride is one of atmospheric polluting material, for control atmosphere pollution, since 2011, country carries out energy-saving, emission-reducing, environment friendly policy energetically, and the discharge of industrial smoke has been formulated to strict standard.Wherein, nitrogen oxides in effluent is processed to qualified discharge through denitration and become important industrial smoke treatment step.In conventional denitration method for flue gas, selective catalytic reduction reaction (SCR) is high with its denitration efficiency, existing equipment is transformed to little advantage becomes the maximum technology of application.SCR technology is under catalyst action, makes NOx reaction in reductive agent ammonia and flue gas, generates the process of the nitrogen G&W of nontoxic pollution-free.The preparation of reductive agent ammonia is often taking urea as raw material, its process and device are: urea and de-mineralized water are made into urea soln and are sprayed in pyrolysis oven by spray nozzle, this injector is plugged on pyrolysis oven, then urea soln is to evaporate under the hot air acting of 350-650 DEG C in temperature, at high temperature react pyrolysis generation ammonia and carbonic acid gas simultaneously with water.In said process, the pyrolysis oven temperature that may exist is too low, urea solution jet atomization not exclusively or the factor such as pyrolysis oven heat retaining property is poor, all can cause urea pyrolysis incomplete, the spout of the easy clogging injector of urea crystals forming.
For do not affect denitrating flue gas continue carry out; conventionally can in denitrating flue gas process, extract every now and then injector inspection; a kind of urea pyrolysis stove with hot-air distributor device efficiently as disclosed in Chinese patent literature CN202909698U; it comprises hot-air distributor, body of heater, urea spray gun interface, ammonia air outlet pipeline; hot-air distributor is arranged on body of heater upper end; urea spray gun interface is arranged on body of heater, and ammonia outlet install pipeline is at bottom of furnace body.
In above-mentioned technology, when extract the injector inspection being plugged on pyrolysis oven from urea spray gun interface time, the NH in pyrolysis oven
3and CO
2under the effect of easily pressing in pyrolysis oven, outwards sprayed by urea spray gun interface, very easily cause loss and the environmental pollution of ammonia raw material, and damaged operator's health.
Utility model content
For this reason, when technical problem to be solved in the utility model is to extract in prior art urea pyrolysis ammonia-preparing device injector and checks nozzle, easily there is NH in pyrolysis oven
3, CO
2the problem leaking, has not only caused environmental pollution, and has damaged operator's health, thereby proposes a kind of pyrolysis oven sealed air device for urea pyrolysis ammonia system processed.
For solving the problems of the technologies described above, the technical solution of the utility model is as follows:
A kind of pyrolysis oven sealed air device for urea pyrolysis ammonia system processed described in the utility model, comprise, housing, on described housing, be provided with injector interface, pyrolysis oven interface and compressed air inlet, all, with the intracavity inter-connection of described housing, described compressed air inlet is between described injector interface and pyrolysis oven interface;
Drainage sleeve, is at least nested with the housing inner chamber being arranged in whole compressed air inlet, and described drainage sleeve is adjacent to the inner side-wall of described housing near the outer side wall of described injector interface, to block the connection of described compressed air inlet and injector interface;
Have multiple perforation around described drainage sleeve near the arranged outside of described pyrolysis oven interface, the drainage sleeve outer side wall between described perforation and pyrolysis oven interface is adjacent to the inner side-wall of described housing;
Described compressed air inlet place, is provided with the gap that extends to perforation between described drainage sleeve outer side wall and housing inner side-wall, and the direction that multiple described perforation enter pyrolysis oven interface near the outer rim of one end, gap along pressurized air becomes contraction structure.
Housing sidewall between described compressed air inlet and pyrolysis oven interface enters pyrolysis oven interface direction along pressurized air and becomes contraction structure.
Described drainage sleeve is adjacent to the inner side-wall setting of housing contraction structure near the outer side wall of pyrolysis oven interface one end.
Described injector interface is arranged at one end of described housing, and accordingly, described pyrolysis oven interface is arranged at the other end of described housing, and described compressed air inlet is arranged at the sidepiece of described housing.
The wedged hole that described perforation is is rectangle along the cross section of the direction perpendicular to perforation axle.
Also comprise the first joint flange that is arranged at described injector interface place and the second joint flange that is arranged at described pyrolysis oven interface.
Described the first joint flange is slip on flange, and described the second joint flange is loose flange.
Described compressed air inlet place connects a stainless steel tube.
Technique scheme of the present utility model has the following advantages compared to existing technology:
(1) a kind of pyrolysis oven sealed air device for urea pyrolysis ammonia system processed described in the utility model, comprise, housing, on described housing, be provided with injector interface, pyrolysis oven interface and compressed air inlet, all, with the intracavity inter-connection of described housing, described compressed air inlet is between described injector interface and pyrolysis oven interface; Drainage sleeve, is at least nested with the housing inner chamber being arranged in whole compressed air inlet, and described drainage sleeve is adjacent to the inner side-wall of described housing near the outer side wall of described injector interface, to block the connection of described compressed air inlet and injector interface; Have multiple perforation around described drainage sleeve near the arranged outside of described pyrolysis oven interface, the drainage sleeve outer side wall between described perforation and pyrolysis oven interface is adjacent to the inner side-wall of described housing; Described compressed air inlet place, is provided with the gap that extends to perforation between described drainage sleeve outer side wall and housing inner side-wall, and the direction that multiple described perforation enter pyrolysis oven interface near the outer rim of one end, gap along pressurized air becomes contraction structure.
While adopting this structure, injector is introduced through being inserted on pyrolysis oven by pyrolysis oven interface after drainage sleeve by injector interface, now drainage sleeve is enclosed within injector outside, when extracting after injector, after pressurized air is introduced by compressed air inlet, because compressed-air actuated pressure is greater than the pressure in pyrolysis oven, pressurized air arrives perforation place along gap, and flow to the central part of the housing inner chamber between drainage sleeve and pyrolysis oven interface along the contraction structure of perforation outer rim, thereby high pressure air can be pressed in pyrolysis oven interface, avoid leak problem of ammonia in pyrolysis oven and carbonic acid gas.
(2) a kind of pyrolysis oven sealed air device for urea pyrolysis ammonia system processed described in the utility model, housing sidewall between described compressed air inlet and pyrolysis oven interface enters pyrolysis oven interface direction along pressurized air and becomes contraction structure, and described drainage sleeve is adjacent to the inner side-wall setting of housing contraction structure near the outer side wall of pyrolysis oven interface one end.After pressurized air enters compressed air inlet, through gap, the contraction structure along housing sidewall more easily flows to perforation, and flow to the central part of the housing inner chamber between drainage sleeve and pyrolysis oven interface near the contraction structure of the outer rim in gap along perforation, be further conducive to compressed-air actuated directed flow.
Brief description of the drawings
For content of the present utility model is more likely to be clearly understood, according to specific embodiment of the utility model also by reference to the accompanying drawings, the utility model is described in further detail, wherein below
Fig. 1 is the structural representation of the gas sealing mechanism drainage sleeve for urea pyrolysis system described in the utility model;
Fig. 2 is the structural representation of the gas sealing mechanism for urea pyrolysis system described in the utility model;
In figure, Reference numeral is expressed as: 1-housing; 2-injector interface; 3-pyrolysis oven interface; 4-compressed air inlet; 5-drainage sleeve; 6-perforation; 7-the first joint flange; 8-the second joint flange; 9-stainless steel tube; 10-gap; 11-perforation is near the outer rim of one end, gap.
Embodiment
Pyrolysis oven sealed air device for urea pyrolysis ammonia system processed described in the utility model, comprise housing 1, on described housing 1, be provided with injector interface 2, pyrolysis oven interface 3 and compressed air inlet 4, all with the intracavity inter-connection of described housing 1, described compressed air inlet 4 is between described injector interface 2 and pyrolysis oven interface 3, in the present embodiment, described injector interface 2 is arranged at one end of described housing 1, described pyrolysis oven interface 3 is arranged at the other end of described housing 1, and described compressed air inlet 4 is arranged at the sidepiece of described housing 1; The shape of described housing 1 can be selected according to actual needs, and in the present embodiment, described housing 1 is cylindrical, and housing 1 sidewall between described compressed air inlet 4 and pyrolysis oven interface 3 enters pyrolysis oven interface 3 directions along pressurized air and becomes contraction structure; Drainage sleeve 5, at least be nested with housing 1 inner chamber being arranged in whole compressed air inlet 4, described drainage sleeve 5 is adjacent to the inner side-wall of described housing 1 near the outer side wall of described injector interface 2, to block the connection of described compressed air inlet 4 and injector interface 2, in the present embodiment, described drainage sleeve 5 is fixedly connected with described housing 1 near one end of described injector interface 2; Within one week, be provided with multiple perforation 6 around described drainage sleeve 5 near the outside of described pyrolysis oven interface 3, in the present embodiment, the outer side wall of the described drainage sleeve 5 between described perforation 6 and pyrolysis oven interface 3 is adjacent to the inner side-wall that is connected housing 1 contraction structure; Described compressed air inlet 4 places, between described drainage sleeve 5 outer side walls and housing 1 inner side-wall, be provided with the gap 10 that extends to perforation 6, the direction that multiple described perforation 6 enter pyrolysis oven interface 3 near the outer rim 11 of one end, gap along pressurized air becomes contraction structure, in the present embodiment, the wedged hole that described perforation 6 is rectangle for the cross section of the direction along perpendicular to perforation axle, in the present embodiment, the concrete structure of drainage sleeve 5 is shown in Fig. 1.
When said apparatus uses, injector is introduced through being inserted on pyrolysis oven by pyrolysis oven interface 3 after drainage sleeve 5 by injector interface 2, now drainage sleeve 5 is enclosed within injector outside, when extracting after injector, after pressurized air is introduced by compressed air inlet 4, because compressed-air actuated pressure is greater than the pressure in pyrolysis oven, pressurized air arrives perforation 6 places along gap 10, and flow to the central part of housing 1 inner chamber between drainage sleeve 5 and pyrolysis oven interface 3 near the contraction structure of the outer rim 11 of one end, gap along perforation, thereby high pressure air can be pressed in pyrolysis oven interface 3, avoid ammonia and the carbonic acid gas in pyrolysis oven to leak.
On the basis of above-described embodiment, as transformable embodiment, as shown in Figure 2, also comprise the first joint flange 7 that is arranged at described injector interface 2 places, in the present embodiment, described the first joint flange 7 is slip on flange; Be arranged at second joint flange 8 at described pyrolysis oven interface 3 places, in the present embodiment, described the second joint flange 8 is loose flange; Described compressed air inlet place connects a stainless steel tube 9.
Obviously, above-described embodiment is only for example is clearly described, and the not restriction to embodiment.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here without also giving exhaustive to all embodiments.And among the protection domain that the apparent variation of being extended out thus or variation are still created in the utility model.
Claims (8)
1. for a pyrolysis oven sealed air device for urea pyrolysis ammonia system processed, it is characterized in that, comprise,
Housing (1), on described housing (1), be provided with injector interface (2), pyrolysis oven interface (3) and compressed air inlet (4), all, with the intracavity inter-connection of described housing (1), described compressed air inlet (4) is positioned between described injector interface (2) and pyrolysis oven interface (3);
Drainage sleeve (5), at least be nested with housing (1) inner chamber being arranged in whole compressed air inlet (4), described drainage sleeve (5) is adjacent to the inner side-wall of described housing (1) near the outer side wall of described injector interface (2), to block the connection of described compressed air inlet (4) and injector interface (2);
Have multiple perforation (6) around described drainage sleeve (5) near the arranged outside of described pyrolysis oven interface (3), drainage sleeve (5) outer side wall between described perforation (6) and pyrolysis oven interface (3) is adjacent to the inner side-wall of described housing (1);
Described compressed air inlet (4) is located, between described drainage sleeve (5) outer side wall and housing (1) inner side-wall, be provided with the gap (10) that extends to perforation (6), the direction that multiple described perforation (6) enter pyrolysis oven interface (3) near the outer rim (11) of one end, gap along pressurized air becomes contraction structure.
2. pyrolysis oven sealed air device according to claim 1, it is characterized in that, housing (1) sidewall between described compressed air inlet (4) and pyrolysis oven interface (3) enters pyrolysis oven interface (3) direction along pressurized air and becomes contraction structure.
3. pyrolysis oven sealed air device according to claim 2, is characterized in that, described drainage sleeve (5) is adjacent to the inner side-wall setting of housing (1) contraction structure near the outer side wall of pyrolysis oven interface (3) one end.
4. according to the arbitrary described pyrolysis oven sealed air device of claim 1-3, it is characterized in that, described injector interface (2) is arranged at one end of described housing (1), accordingly, described pyrolysis oven interface (3) is arranged at the other end of described housing (1), and described compressed air inlet (4) is arranged at the sidepiece of described housing (1).
5. pyrolysis oven sealed air device according to claim 4, is characterized in that, the wedged hole that described perforation (6) is rectangle for the cross section of the direction along perpendicular to perforation axle.
6. according to the pyrolysis oven sealed air device described in claim 1 or 2 or 3 or 5, it is characterized in that, also comprise and be arranged at the first joint flange (7) that described injector interface (2) locates and be arranged at the second joint flange (8) that described pyrolysis oven interface (3) is located.
7. pyrolysis oven sealed air device according to claim 6, is characterized in that, described the first joint flange (7) is slip on flange, and described the second joint flange (8) is loose flange.
8. according to the pyrolysis oven sealed air device described in claim 1 or 2 or 3 or 5 or 7, it is characterized in that, described compressed air inlet place connects a stainless steel tube (9).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420246638.9U CN203833627U (en) | 2014-05-14 | 2014-05-14 | Pyrolysis furnace air sealing device for system for ammonia production by pyrolysis of urea |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420246638.9U CN203833627U (en) | 2014-05-14 | 2014-05-14 | Pyrolysis furnace air sealing device for system for ammonia production by pyrolysis of urea |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203833627U true CN203833627U (en) | 2014-09-17 |
Family
ID=51511498
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420246638.9U Expired - Lifetime CN203833627U (en) | 2014-05-14 | 2014-05-14 | Pyrolysis furnace air sealing device for system for ammonia production by pyrolysis of urea |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203833627U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110102156A (en) * | 2019-05-21 | 2019-08-09 | 南京杰科丰环保技术装备研究院有限公司 | The device of spray gun is replaced or overhauled online to a kind of urea pyrolysis reactor |
| CN113968586A (en) * | 2021-10-26 | 2022-01-25 | 西安热工研究院有限公司 | Sealing air pipe seat of urea pyrolysis spray gun |
-
2014
- 2014-05-14 CN CN201420246638.9U patent/CN203833627U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110102156A (en) * | 2019-05-21 | 2019-08-09 | 南京杰科丰环保技术装备研究院有限公司 | The device of spray gun is replaced or overhauled online to a kind of urea pyrolysis reactor |
| CN113968586A (en) * | 2021-10-26 | 2022-01-25 | 西安热工研究院有限公司 | Sealing air pipe seat of urea pyrolysis spray gun |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20140917 |
|
| CX01 | Expiry of patent term |