CN103663494A - Urea pyrolysis device and pretreatment device for flue gas denitrification as well as denitrification system - Google Patents
Urea pyrolysis device and pretreatment device for flue gas denitrification as well as denitrification system Download PDFInfo
- Publication number
- CN103663494A CN103663494A CN201310665068.7A CN201310665068A CN103663494A CN 103663494 A CN103663494 A CN 103663494A CN 201310665068 A CN201310665068 A CN 201310665068A CN 103663494 A CN103663494 A CN 103663494A
- Authority
- CN
- China
- Prior art keywords
- flue gas
- pyrolysis
- urea
- back end
- outlet
- 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
Links
Images
Landscapes
- Treating Waste Gases (AREA)
Abstract
The invention discloses a urea pyrolysis device. The urea pyrolysis device comprises a boiler rear flue (1) and a pyrolysis chamber (3), wherein a urea spray gun (4) is arranged on the pyrolysis chamber (3), an outlet (5) for discharging a pyrolysis product and a flue gas inlet (8) are formed in the pyrolysis chamber (3), and the flue gas inlet (8) is connected to the boiler rear flue (1). The invention also discloses a pretreatment device for flue gas denitrification, which comprises the urea pyrolysis device. In addition, the invention also discloses a denitrification system which comprises the urea pyrolysis device or the pretreatment device connected to a denitrification reactor. The urea pyrolysis device disclosed by the invention has the advantages that urea is decomposed by using the heat energy of boiler rear flue gas, the heat energy in exhaust gas is effectively utilized, the device is used for flue gas denitrification and is simple in system structure and relatively low in denitrification cost, and the safety performance is improved.
Description
Technical field
The present invention relates to denitrating flue gas field, particularly, relate to a kind of urea pyrolysis device.On this basis, the invention still further relates to a kind of pretreatment unit for denitrating flue gas.In addition, the invention still further relates to a kind of out of stock system that comprises described pretreatment unit.
Background technology
Along with socioeconomic rapid growth, the discharge of China's atmospheric polluting material is also on the increase, and has caused series of environmental problems thus.Wherein, oxynitride (NOx) is the principal element that causes acid rain, and in power plant boiler flue gas, comprises a large amount of oxynitride, one of emphasis of Ye Shi China emission reduction work.
At present, the oxynitride in boiler smoke is mainly removed by denitration reaction by thermal power plant, obtains good effect.Its principle is (to be often ammonia NH by reductive agent
3) NOx in flue gas is reduced to nitrogen G&W, therefore select which kind of material to provide denitrification reducing agent in denitrating system, to play vital effect.The reactive material that is usually used in SCR (SCR) and non-selective catalytic reduction (SNCR) mainly contains three kinds: liquefied ammonia, ammoniacal liquor and urea.Wherein, liquefied ammonia and ammoniacal liquor all have explosivity and larger toxicity, in transportation and storage process, all have safety issue; And urea is white or lurid xln, soluble in water, be the conventional fertilizer of agricultural, non-explosive and danger, security is higher.Given this, urea is often used to manufacture ammonia as the reductive agent in denitrating system.
Urea ammonia processed has hydrolysis and two kinds of methods of pyrolysis conventionally.Biuret and other condensess that the perishable electric power factory equipment of acidic substance producing in hydrolysis of urea process and generation are insoluble in water, easily stop up hydrolysis system; And urea pyrolysis is difficult for producing intermediate polymer.Therefore, the denitration reaction thing of thermal power plant more and more tends to adopt urea pyrolysis technology, urea pyrolysis comprises combustion heating and two kinds of heating means of electrically heated air, enters pyrolysis urea soln in pyrolysis oven after making to be heated to certain temperature from the air in air preheater.In this method, high temperature is the prerequisite that obtains high conversion.
Although urea pyrolysis system operating safety stability is high, in pyrolysis oven bottom and tail pipe place, easily produce cellular settling, thus blocking pipe.This is mainly caused by following two aspects: first, pyrolysis chamber's interior flow field is inhomogeneous, likely causes temperature deviation, and the region that local temperature is lower easily forms crystallization; In addition, the urea soln after partly atomized is too short at residing time in furnace, causes urea also not have enough time to decompose, and easily in outlet and pipeline, forms crystallization.Secondly, not high enough owing to adding hot air temperature, be difficult for making urea to stablize pyrolysis, in pyrolysis oven exit, form crystallization.
In addition, no matter utilize hydrolysis or pyrolysis way carries out urea ammonia processed, all need special heating installation (combustion heating or electrically heated), further consume the energy, make denitration cost higher, system architecture complexity.
Summary of the invention
Problem to be solved by this invention is to provide a kind of urea pyrolysis device, and this urea pyrolysis device can be effective to urea ammonia processed, be difficult for to form stops up, and simplified construction, reduces costs.
To achieve these goals, the invention provides a kind of urea pyrolysis device, this urea pyrolysis device comprises boiler back end ductwork and pyrolysis chamber, in described pyrolysis chamber, urea spray gun is installed, and in this pyrolysis chamber, be formed with for discharging outlet and the gas approach of pyrolysis product (being mainly the mixture of ammonia and flue gas), this gas approach is connected in described boiler back end ductwork, the flue gas in described boiler back end ductwork can be incorporated in described pyrolysis chamber.
Preferably, described boiler back end ductwork has high-temperature flue gas mouth, and wherein said gas approach is connected in described high-temperature flue gas mouth.
Preferably, described gas approach is introduced pipeline by flue gas and is connected in described boiler back end ductwork.
On this basis, the present invention also provides a kind of pretreatment unit for denitrating flue gas, this pretreatment unit comprises the urea pyrolysis device described in above-mentioned any one technical scheme, wherein, on described boiler back end ductwork, there is main flue gas mouth, and the described outlet of described pyrolysis chamber and described main flue gas mouth are connected respectively in mixing device, so that described flue gas and described pyrolysis product are pre-mixed.
Preferably, described mixing device is spray ammonia grid or flue gas mixing tank.
Preferably, described outlet is connected to described mixing device by pyrolysis product transport pipe, and described main flue gas outlet is connected to described mixing device by main flue gas pipeline.
In addition, the present invention also provides a kind of denitrating system, and this denitrating system comprises the pretreatment unit described in above-mentioned any one technical scheme, and this pretreatment unit is connected to Benitration reactor.
The present invention also provides a kind of denitrating system, this denitrating system comprises the urea pyrolysis device described in above-mentioned any one technical scheme, wherein, on described boiler back end ductwork, there is main flue gas mouth, and the described outlet of described pyrolysis chamber and described main flue gas mouth are connected respectively to Benitration reactor.
Preferably, described outlet is connected to described Benitration reactor by pyrolysis product transport pipe, and described main flue gas outlet is connected to described Benitration reactor by main flue gas pipeline.
By technique scheme, urea pyrolysis device of the present invention utilizes the heat of boiler tail flue gas by urea decomposition, effectively utilizes the heat energy in waste gas.High-temperature flue gas is directly passed into the pyrolysis that pyrolysis chamber carries out urea soln, saved the step that electrically heated air or fuel combustion add warm air, system is simplified, reduced denitration cost, improved safety performance.Meanwhile, solved the Crystallization Plugging problem producing not due to pyrolysis temperature, for the normal operation of denitrating system provides guarantee.
Other features and advantages of the present invention partly in detail are described the embodiment subsequently.
Accompanying drawing explanation
Accompanying drawing is to be used to provide a further understanding of the present invention, and forms a part for specification sheets, is used from explanation the present invention, but is not construed as limiting the invention with embodiment one below.In the accompanying drawings:
Fig. 1 is according to the connection diagram of the pretreatment unit for denitrating flue gas of the specific embodiment of the invention.
Description of reference numerals
1 back-end ductwork 2 high-temperature flue gas mouths
3 pyrolysis chamber's 4 urea spray guns
5 outlet 6 main flue gas mouths
7 spray ammonia grid 8 gas approachs
9 flue gases are introduced pipeline 10 pyrolysis product transport pipes
11 main flue gas pipelines
Embodiment
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is elaborated.Should be understood that, embodiment described herein only, for description and interpretation the present invention, is not limited to the present invention.
As shown in Figure 1, according to a kind of embodiment of urea pyrolysis device of the present invention, this this urea pyrolysis device comprises boiler back end ductwork 1 and pyrolysis chamber 3, in described pyrolysis chamber 3, urea spray gun 4 is installed, and in this pyrolysis chamber 3, be formed with for discharging outlet 5 and the gas approach 8 of pyrolysis product, this gas approach 8 is connected in described boiler back end ductwork 1, the flue gas in described boiler back end ductwork 1 can be incorporated in described pyrolysis chamber 3.Utilize the heat energy of the high-temperature flue gas of boiler generation, urea spray gun 4 is sprayed into the urea soln of pyrolysis chamber 3, system architecture is simple, has reduced cost.Can be for the occasion not high to ammonia purity requirement by exporting the pyrolysis product of 5 discharges.
Above-mentioned boiler back end ductwork 1 should be able to provide the flue gas of comparatively high temps, is preferably not less than 600 ℃, and therefore urea pyrolysis device of the present invention is relatively applicable to utilizing Industrial Boiler, especially the boiler back end ductwork of power plant boiler.Further, the flue gas of discharging for described boiler carries out denitration processing, and its advantage describes in detail also continuing in content subsequently.
Particularly, described boiler back end ductwork 1 has high-temperature flue gas mouth 2, and the position that this high-temperature flue gas mouth 2 is preferably near burner hearth offers, and to obtain higher temperature, wherein said gas approach 8 is connected in described high-temperature flue gas mouth 2.Usually, by flue gas, introduce the connection that pipeline 9 carries out between the two.Situation about allowing in structural strength or under the pressure of the restriction in space, also can directly dock high-temperature flue gas mouth 2 with gas approach 8.
On this basis, the present invention also provides a kind of pretreatment unit for denitrating flue gas, as shown in Figure 1.This pretreatment unit comprises above-mentioned urea pyrolysis device, wherein, on described boiler back end ductwork 1, there is main flue gas mouth 6, on boiler back end ductwork 1, be formed with two flue gas mouths: high-temperature flue gas mouth 2 is connected for the gas approach 8 with pyrolysis chamber 3, for urea soln decompose provide a small amount of flue gas as thermal source; Main flue gas mouth 6 is for discharging a large amount of flue gas of residue.In addition, the described outlet 5 of described pyrolysis chamber 3 and described main flue gas mouth 6 are connected respectively in mixing device, so that be pre-mixed by flue gas and the described pyrolysis product of described main flue gas mouth 6 discharges, for ready by the denitrating flue gas of main flue gas mouth 6 discharges.
Particularly, described mixing device is spray ammonia grid 7 or flue gas mixing tank.And as shown in Figure 1, described outlet 5 can be connected to described mixing device by pyrolysis product transport pipe 10, described main flue gas outlet 6 can be connected to described mixing device by main flue gas pipeline 11.
Further, the present invention also provides a kind of denitrating system, this denitrating system comprises above-mentioned urea pyrolysis device, wherein, on described boiler back end ductwork 1, there is main flue gas mouth 6, and the described outlet 5 of described pyrolysis chamber 3 and described main flue gas mouth 6 are connected respectively to Benitration reactor, thereby carry out redox reaction in this Benitration reactor.First this denitrating system utilizes the heat of the flue gas self of its discharge that urea soln is decomposed, and then utilizing degradation production is nitrogen G&W by the conversion of nitrogen oxides in flue gas.Structure than utilizing ammoniacal liquor or liquefied ammonia denitration, has improved security; Than traditional hydrolysis of urea and pyrolysis ammonia processed, do not need special heating installation, simplify system, saved cost.During in particular for power plant boiler, due to the flue-gas temperature higher (generally reaching more than 800 ℃) of its discharge, pyrolysis efficiency is higher, can avoid to a certain extent undecomposed urea crystals blocking pipe.
In above-mentioned denitrating system, described outlet 5 is connected to described Benitration reactor by pyrolysis product transport pipe 10, and described main flue gas outlet 6 is connected to described Benitration reactor by main flue gas pipeline 11.
In addition, the present invention is a kind of denitrating system also, and this denitrating system comprises above-mentioned pretreatment unit, and this pretreatment unit is connected to Benitration reactor.
Below describe by reference to the accompanying drawings the preferred embodiment of the present invention in detail; but; the present invention is not limited to the detail in above-mentioned embodiment; within the scope of technical conceive of the present invention; can carry out multiple simple variant to technical scheme of the present invention, these simple variant all belong to protection scope of the present invention.
It should be noted that in addition each the concrete technical characterictic described in above-mentioned embodiment, in reconcilable situation, can combine by any suitable mode.For fear of unnecessary repetition, the present invention is to the explanation no longer separately of various possible array modes.
In addition, between various embodiment of the present invention, also can carry out arbitrary combination, as long as it is without prejudice to thought of the present invention, it should be considered as content disclosed in this invention equally.
Claims (9)
1. a urea pyrolysis device, it is characterized in that, this urea pyrolysis device comprises boiler back end ductwork (1) and pyrolysis chamber (3), urea spray gun (4) is installed in described pyrolysis chamber (3), and on this pyrolysis chamber (3), be formed with outlet (5) and gas approach (8) for discharging pyrolysis product, this gas approach (8) is connected in described boiler back end ductwork (1), the flue gas in described boiler back end ductwork (1) can be incorporated in described pyrolysis chamber (3).
2. urea pyrolysis device according to claim 1, is characterized in that, described boiler back end ductwork (1) has high-temperature flue gas mouth (2), and wherein said gas approach (8) is connected in described high-temperature flue gas mouth (2).
3. urea pyrolysis device according to claim 1 and 2, is characterized in that, described gas approach (8) is introduced pipeline (9) by flue gas and is connected in described boiler back end ductwork (1).
4. the pretreatment unit for denitrating flue gas, it is characterized in that, this pretreatment unit comprises according to the urea pyrolysis device described in any one in claims 1 to 3, wherein, on described boiler back end ductwork (1), there is main flue gas mouth (6), and described outlet (5) and the described main flue gas mouth (6) of described pyrolysis chamber (3) are connected respectively in mixing device, so that flue gas and the described pyrolysis product of discharging by described main flue gas mouth (6) are pre-mixed.
5. pretreatment unit according to claim 4, is characterized in that, described mixing device is spray ammonia grid (7) or flue gas mixing tank.
6. according to the pretreatment unit described in claim 4 or 5, it is characterized in that, described outlet (5) is connected to described mixing device by pyrolysis product transport pipe (10), and described main flue gas outlet (6) is connected to described mixing device by main flue gas pipeline (11).
7. a denitrating system, is characterized in that, this denitrating system comprises according to the pretreatment unit described in any one in claim 4 to 6, and this pretreatment unit is connected to Benitration reactor.
8. a denitrating system, it is characterized in that, this denitrating system comprises according to the urea pyrolysis device described in any one in claims 1 to 3, wherein, on described boiler back end ductwork (1), there is main flue gas mouth (6), and the described outlet (5) of described pyrolysis chamber (3) and described main flue gas mouth (6) are connected respectively to Benitration reactor.
9. denitrating system according to claim 8, it is characterized in that, described outlet (5) is connected to described Benitration reactor by pyrolysis product transport pipe (10), and described main flue gas outlet (6) is connected to described Benitration reactor by main flue gas pipeline (11).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310665068.7A CN103663494A (en) | 2013-12-10 | 2013-12-10 | Urea pyrolysis device and pretreatment device for flue gas denitrification as well as denitrification system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310665068.7A CN103663494A (en) | 2013-12-10 | 2013-12-10 | Urea pyrolysis device and pretreatment device for flue gas denitrification as well as denitrification system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103663494A true CN103663494A (en) | 2014-03-26 |
Family
ID=50302401
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310665068.7A Pending CN103663494A (en) | 2013-12-10 | 2013-12-10 | Urea pyrolysis device and pretreatment device for flue gas denitrification as well as denitrification system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103663494A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104649297A (en) * | 2015-01-13 | 2015-05-27 | 神华集团有限责任公司 | Urea pyrolysis device, urea denitration device and urea denitration method |
| CN105645435A (en) * | 2016-03-25 | 2016-06-08 | 上海益格新技术工程有限公司 | Flue gas denitration urea pyrolysis air supply system of gas generator/gas turbine |
| CN108211694A (en) * | 2018-02-11 | 2018-06-29 | 中国华电科工集团有限公司 | A kind of denitrating flue gas urea liquid pyrolysis system |
| CN109529622A (en) * | 2019-01-16 | 2019-03-29 | 北京工大环能科技有限公司 | One kind being used for more gas internal-combustion engine flue gas tail portion denitrating systems |
| CN112742214A (en) * | 2019-10-30 | 2021-05-04 | 沪东重机有限公司 | Urea decomposition and mixing integrated device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080050297A1 (en) * | 2006-08-22 | 2008-02-28 | Babcock Power, Inc. | Thermal Decomposition of Urea in a Side Stream of Combustion Flue Gas Using a Regenerative Heat Exchanger |
| CN102068904A (en) * | 2010-12-10 | 2011-05-25 | 中电投远达环保工程有限公司 | SCR flue gas denitration technology and device by urea directly-spraying method |
| JP4716325B2 (en) * | 2006-04-11 | 2011-07-06 | バブコック日立株式会社 | Flue gas denitration device and operation method thereof |
| CN102794106A (en) * | 2012-08-22 | 2012-11-28 | 东方电气集团东方锅炉股份有限公司 | Method and device for spraying reducing agent used for selective catalytic reduction (SCR) of NOx |
| CN203653264U (en) * | 2013-12-10 | 2014-06-18 | 神华集团有限责任公司 | Urea pyrolysis device and pretreatment device for flue gas denitration as well as denitration system |
-
2013
- 2013-12-10 CN CN201310665068.7A patent/CN103663494A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4716325B2 (en) * | 2006-04-11 | 2011-07-06 | バブコック日立株式会社 | Flue gas denitration device and operation method thereof |
| US20080050297A1 (en) * | 2006-08-22 | 2008-02-28 | Babcock Power, Inc. | Thermal Decomposition of Urea in a Side Stream of Combustion Flue Gas Using a Regenerative Heat Exchanger |
| CN102068904A (en) * | 2010-12-10 | 2011-05-25 | 中电投远达环保工程有限公司 | SCR flue gas denitration technology and device by urea directly-spraying method |
| CN102794106A (en) * | 2012-08-22 | 2012-11-28 | 东方电气集团东方锅炉股份有限公司 | Method and device for spraying reducing agent used for selective catalytic reduction (SCR) of NOx |
| CN203653264U (en) * | 2013-12-10 | 2014-06-18 | 神华集团有限责任公司 | Urea pyrolysis device and pretreatment device for flue gas denitration as well as denitration system |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104649297A (en) * | 2015-01-13 | 2015-05-27 | 神华集团有限责任公司 | Urea pyrolysis device, urea denitration device and urea denitration method |
| CN104649297B (en) * | 2015-01-13 | 2017-03-29 | 神华集团有限责任公司 | Urea pyrolysis device and the method for carbamide denitrification apparatus and carbamide denitration |
| CN105645435A (en) * | 2016-03-25 | 2016-06-08 | 上海益格新技术工程有限公司 | Flue gas denitration urea pyrolysis air supply system of gas generator/gas turbine |
| CN108211694A (en) * | 2018-02-11 | 2018-06-29 | 中国华电科工集团有限公司 | A kind of denitrating flue gas urea liquid pyrolysis system |
| CN109529622A (en) * | 2019-01-16 | 2019-03-29 | 北京工大环能科技有限公司 | One kind being used for more gas internal-combustion engine flue gas tail portion denitrating systems |
| CN109529622B (en) * | 2019-01-16 | 2023-11-14 | 北京工大环能科技有限公司 | Flue gas tail denitration system for multiple gas internal combustion engines |
| CN112742214A (en) * | 2019-10-30 | 2021-05-04 | 沪东重机有限公司 | Urea decomposition and mixing integrated device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105289233B (en) | A kind of coal-burning boiler SNCR and SCR combined denitration system and method | |
| CN103663494A (en) | Urea pyrolysis device and pretreatment device for flue gas denitrification as well as denitrification system | |
| CN103301747A (en) | SCR (Selective Catalytic Reduction) flue gas denitration device for urea pyrolysis | |
| CN102091511A (en) | Device and method for denitration on flue gas by coupling selective non catalytic reduction and catalytic reduction | |
| CN107261837A (en) | It is a kind of to quote denitrification apparatus and technique that high-temperature flue gas carries out urea pyrolysis ammonia | |
| CN103611411A (en) | Dry denitration processing device in furnace | |
| CN110903042A (en) | Double-hearth lime kiln with denitration equipment | |
| CN203316010U (en) | Flue gas denitration system with SCR and SNCR coupled | |
| CN104329946B (en) | A kind of coke oven flue exhaust gas denitration and the integral system of waste heat recovery | |
| CN103691267A (en) | Low-temperature synchronous denitration and desulfurization equipment and process for flue gas | |
| CN104307347A (en) | Efficient SNCR point-to-point injection system | |
| CN203342651U (en) | Urea pyrolysis and SCR (selective catalytic reduction) flue gas denitrification device | |
| CN203653264U (en) | Urea pyrolysis device and pretreatment device for flue gas denitration as well as denitration system | |
| CN102671532B (en) | Enhanced selective non-catalytic reduction flue gas denitrification method | |
| CN103727803B (en) | A kind of equipment for denitrifying flue gas | |
| CN204447709U (en) | A kind of SNCR denitration system | |
| CN102671517A (en) | Device for performing urea pyrolysis by utilizing smoke thermal enthalpy | |
| CN207680333U (en) | Urea direct-injection SNCR+SCR flue gas denitrification systems | |
| CN100434142C (en) | Process for realizing medium temperature dry-method direct denitration of flue gas by using ethanol | |
| CN202983514U (en) | Integrated SCR-SNCR (silicon controlled rectifier-selective non-catalytic reduction) combined denitration system | |
| CN205145943U (en) | Coal fired boiler SNCR and SCR unite deNOx systems | |
| CN104524939A (en) | Glass denitrification system based on SNCR technology | |
| CN205592943U (en) | Circulating fluidized bed boiler | |
| CN201565242U (en) | Selective non-catalytic reduction and catalytic reduction coupling smoke and gas denitration device | |
| CN211896058U (en) | Urea pyrolysis system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20140326 |