CN109173639A - A kind of nitric acid tail gas denitrating technique - Google Patents
A kind of nitric acid tail gas denitrating technique Download PDFInfo
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- CN109173639A CN109173639A CN201811319340.5A CN201811319340A CN109173639A CN 109173639 A CN109173639 A CN 109173639A CN 201811319340 A CN201811319340 A CN 201811319340A CN 109173639 A CN109173639 A CN 109173639A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation 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
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/54—Nitrogen compounds
- B01D53/56—Nitrogen oxides
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation 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
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation 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
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
- B01D53/8628—Processes characterised by a specific catalyst
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/20—Reductants
- B01D2251/206—Ammonium compounds
- B01D2251/2062—Ammonia
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Abstract
The invention belongs to nitric acid production plant technical fields, are a kind of nitric acid tail gas denitrating technique.The technique is to synthesize the ammonia tank periodic off-gases of ammonia as reducing agent, it is sprayed into certain temperature (depending on the initial activity temperature of catalyst) nitric acid tail gas, enter Benitration reactor afterwards by evenly mixing, wherein hydrogen is reacted with oxygen generates water, gas ammonia decomposes the NOx in tail gas the nitrogen and water vapour for generating no pollution to the environment, is finally discharged to atmosphere.Reducing agent can both have been reduced the difficulty and energy consumption of periodic off-gases recycling, and decreased the use of raw material ammonia using synthesis ammonia tank periodic off-gases.The characteristics of easily being reacted with oxygen using hydrogen, can activated catalyst at a lower temperature, react ammonia with the selection of NOx and be easier to carry out.And speed to bleed off pressure power higher than nitric acid tail gas pressure and very stable, it also avoids using compression needed for gas ammonia or pressurization vaporescence, whole flow process is with low investment, stable operation, operating cost is low, emission reduction effect is good.
Description
Technical field
The invention belongs to nitric acid production plant technical field, specially a kind of nitric acid tail gas denitrating technique.
Background technique
Nitric acid industry in chemical industry has high pollution.China has become the first big country of global nitric acid production,
So pollution control and environmental management are similarly developed and pay attention to.During nitric acid production, NOx discharge is larger, and
Oxynitrides is one of the priming factors of air pollution again, and excessive NOx emission necessarily causes environmental disruption and to human body
Harm, so prevention and treatment NOx pollution is most important.
Currently, production nitric acid after the alternative method of emission NOx denitration there are many kinds of, but consider it is easy to operate,
The many factors such as effect stability, service life length, cost, energy conservation, row up to standard is realized using selective catalytic reduction reaction
It is placed with very big advantage, i.e., NOx is reduced into nitrogen and water under the action of catalyst using ammonia, to reduce the pollution to environment,
Here it is selective catalytic reduction denitration technologies.But existing selective catalytic reduction reaction (SCR method) is restored with gas ammonia
Agent consumes raw material gas ammonia, and because gas ammonia flow is small, is easy to appear local mixing non-uniform phenomenon, causes local NH3/ NOx moles
Than inappropriate, emission reduction effect is directly affected, also increases system ammonia consumption.Additionally due to nitric acid plant gas ammonia and emission reduction gas ammonia
Pressure rating is inconsistent, needs additionally to increase the device for providing elevated pressures gas ammonia (such as ammonia compressor or pressurization ammonia steaming device),
Lead to that the production cost increases.
Summary of the invention
It is an object of the invention to the deficiencies to technology in existing process unit, provide a kind of nitric acid tail gas denitration work
Skill.The technique is combined with the nitric plant of synthetic ammonia installation, and the periodic off-gases to synthesize the generation of ammonia ammonia tank are injected into high temperature as reducing agent
In nitric acid tail gas pipeline, enter Benitration reactor after mixing, utilizes the hydrogen and oxygen in periodic off-gases under the action of catalyst
Solid/liquid/gas reactions generate water, and gas ammonia decomposes the nitrogen oxides in tail gas the nitrogen and water vapour for generating no pollution to the environment, most heel row
To atmosphere, entire energy saving technology, high efficiency, low cost.
In order to realize the above goal of the invention, the application's the specific technical proposal is:
A kind of nitric acid tail gas denitrification apparatus, including synthesis ammonia tank, mixer, reactor, heat-exchanger rig and online tail gas NOx contain
Amount, wherein successively set distance-transmission pressure gauge, teletransmission thermometer, filter, ratio adjusting valve between synthesis ammonia tank and mixer
And check-valves
A kind of nitric acid tail gas denitrating technique comprising following steps:
Step 1: the periodic off-gases from synthesis ammonia tank are removed the particulate matter that may be carried secretly by filter, are measured through flowmeter
Afterwards, by regulating system adjust flow and be depressurized to the high 0.2 ~ 0.5MPa of ratio exhaust gas pressure (double pressing technologies then pressure 1.0 ~
1.2MPa), the periodic off-gases flow after adjusting controls ammonia flow in periodic off-gases with NOx content NH3:NOx (volumetric concentration) in tail gas
System is between certain proportion (1.0 ~ 1.1), and wherein NOx content has passed through online NOx measuring instrument and measured, system-computed proportional quantity
After provide corresponding regulating valve position, by check-valves, after being measured by periodic off-gases flowmeter, subsequently into mixer.
It (depending on catalyst initial activation temperature, is catalyzed step 2: the preheating of nitric acid plant tail gas is reached certain temperature
Agent is the catalyst of existing maturation, and the active temperature of each catalyst is each identical, and the active temperature of usual middle temperature catalyst is 200
DEG C) after exhaust pipe in one section be transformed into pipeline mixer.Reach catalysis through pressure and temperature meter detection exhaust temperature
The active temperature point that agent requires, and make the NH in gaseous mixture by after NOx measuring instrument NOx content, adjusting periodic off-gases flow3: NOx
Reach 1.0 ~ 1.1 requirement, periodic off-gases are sprayed through rake spray orifice, then after two-stage static state structured packing mixer tail gas with speed
Deflation is adequately mixed, and has carried out sufficient preparation for reaction.
Step 3: into after reactor by the way that among reactor, to reduce reactor beds layer resistance, reactor is respectively set
For upper layer and lower layer.Mixed tail gas flows up and down respectively by catalyst upper bed layer, catalyst lower bed layer, under
The reaction gas of bed enters reactor outlet after cross over pipe converges, as the carry out reaction bed temperature of reaction gradually mentions
Height, catalyst bed temperature rise usual for double pressing technology tail gas, which reaches 3 DEG C ~ 8 DEG C or so, can meet nitrogen oxides decoloration requirement.
Pressure difference measures by teletransmission differential manometer and is sent to master control room monitoring before and after reactor, causes to prevent pressure difference is excessive to nitric acid system
It influences.
Step 4: according to the difference of dust technology technique, after the tail gas after decolourizing does work using each heat exchanger, expanding machine
Discharge outlet is eventually arrived at, by the sample tap on discharge outlet, the NOx through on-line measurement instrument precise measurement sample tap, if symbol
Newest industrial discharge standard is closed, and analysis result is sent to master station by signal wire to increase and decrease periodic off-gases flow.
For synthesis ammonia tank periodic off-gases in the first step from synthesis ammonia ammonia tank, ammonia tank is pressurized tank, the pressure of periodic off-gases
Power is usually 2.1MPa, forms the NH in terms of volumn concentration3: 38 ~ 45%, H2: 38 ~ 45%, CH4~ 8%, N2~ 14%, total volume
The sum of percentage composition is 100%.Usual ammonia tank periodic off-gases are to be washed with water for weak aqua ammonia, then parsing is sent to isolate through steam heating
Gas ammonia, gas ammonia are cooled to liquefied ammonia, direct discharging of waste water again, and the tail gas after washing send primary reformer to make fuel.And nitric acid tail gas SCR
Reducing agent is gas ammonia in method, and due to the oxidative pressure for absorbing tail gas pressure and being higher than ammonia in usual nitric acid process, liquefied ammonia is needed
Pressurized evaporation becomes 1.0MPa gas ammonia, or send tail gas to restore again after compression with low pressure gas ammonia.Directly made using periodic off-gases
Reducing agent can then save the recovery ammonia complex process and energy consumption of periodic off-gases, meanwhile, the H in gaseous mixture2Also it can be catalyzed
The lower reaction of agent effect generates H2O, which easily carries out, thus can provide heat for the Chemoselective reduction of NOx.Simultaneously
Ammonia tank periodic off-gases pressure is stablized, and component is also very stable, therefore operating reliability is strong.In short, using ammonia tank periodic off-gases as reduction
Agent not only can be reduced the investment and energy consumption of periodic off-gases recovery processing, but also have very strong operating reliability, and very good solution speeds to put
Gas recycles problem.
In the mixer of the second step, periodic off-gases ingress pipe is protruded into exhaust pipe, is welded on ingress pipe several
The branch pipe of row sidewards, branch tube spacing 100mm(branch pipe quantity is depending on exhaust pipe diameter), branch pipe tail end and pipeline are fixed
Block welding fixation, two side directions of vertical exhaust gas flow direction offer the spray orifice of Ф 1mm, spray orifice spacing on branch pipe(tube)
50mm, i.e. rake spray orifice, eject periodic off-gases by spout；This injection apparatus is adapted to the lesser gas of injection flow
Body makes it relatively evenly to spray in tail gas.Due to jet port bore very little, so being provided with filtering on periodic off-gases general pipeline
Device is to filter the particulate matter that may be carried secretly in periodic off-gases.Mixing chamber replaces peace with two sections of blank pipe sections using stainless steel structured filling material layer
Dress；Stainless steel structured filling material layer is two groups, and stainless steel structured packing is fixed on tube wall, and filler arrangement angle layer successively misplaces
Alternately, and it is vertical with airflow direction, so that periodic off-gases and sweep gas mixture has been reached fluid dispersion and well-mixed purpose.
Periodic off-gases in the third step are injected into high temperature nitric acid tail gas Benitration reactor as denitrfying agent, in periodic off-gases
Effective component ammonia decomposes the nitrogen oxides in tail gas under catalysts selective effect the nitrogen for generating no pollution to the environment
And water, reaction equation are as follows:
6NO+4NH3→5N2+6H2O+1807.0KJ/mol
6NO2+8NH3→7N2+12H2O+2659.9kJ/mol
And oxygen and hydrogen react
H2+0.5O2→H2O+286KJ/mol。
Catalyst is existing mature catalyst, is provided by relevant catalyst producer, reaction temperature is then according to selection
Depending on catalyst, the range of reaction temperature of common senior middle school's low temperature catalyst is at 160 ~ 380 DEG C.
The positive effect of the present invention is embodied in:
(1), this technique is combined with the nitric plant of synthetic ammonia installation, is injected into high temperature nitric acid tail gas pipe to synthesize the periodic off-gases of ammonia
In road, enter Benitration reactor after mixing, hydrogen in periodic off-gases etc. is utilized under catalyst and specific temperature effect then
It is reacted with oxygen and generates water, gas ammonia decomposes the nitrogen oxides in tail gas the nitrogen and water vapour for generating no pollution to the environment, most
Row arrives atmosphere afterwards, reduces the generation of environmental pollution.
(2), reducing agent both can reduce periodic off-gases recycling directly using ammonia relief gas is contained using synthesis ammonia tank periodic off-gases
The difficulty of processing decreases the use of raw material ammonia, furthermore makees reducing agent using periodic off-gases, is easily reacted with oxygen using hydrogen
The characteristics of, can activated catalyst at a lower temperature, react ammonia with the selection of NOx and be easier to carry out.Simultaneously because ammonia tank is speeded
Power is bled off pressure higher than nitric acid tail gas pressure and very stable, therefore is also avoided using compression needed for gas ammonia or steam under pressure process,
Whole flow process is with low investment, stable operation, operating cost is low, emission reduction effect is good.
Detailed description of the invention:
Fig. 1 is heretofore described nitric acid tail gas denitrating technique flow diagram.
Fig. 2 is the structural schematic diagram of heretofore described mixer.
Wherein: 1- periodic off-gases, 2- distance-transmission pressure gauge, 3- teletransmission thermometer, 4- filter, 5- ratio adjusting valve, 6- non-return
Valve, 7- mixer, 8- exhaust pipe, 9- distance-transmission pressure gauge, 10- teletransmission thermometer, 11- reactor, 12- catalyst upper bed layer,
13- catalyst lower bed layer, 14- cross over pipe, 15- teletransmission differential manometer, 16- discharge outlet, 17- sample tap, 18- on-line measurement instrument, 19-
Reaction bed temperature meter, 20- periodic off-gases flowmeter, the online tail gas NOx content measuring device of 21-, N1- inlet exhaust gas, N2- tail
Gas outlet, N3- periodic off-gases import, 22- jet segment, 23- Turbogrid plates, 24- support plate, 25- structured filling material layer, 26- lifting lug, 27-
System control cabinet, 28- master controller.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.
Involved % indicates its volumn concentration, i.e. %vol unless otherwise specified in the application.
Embodiment 1:
A kind of nitric acid tail gas denitrating technique, for double pressurization dust technology process tail gas, temperature selective reducing catalyst in selecting
In the case where (commercially available), selective reduction catalyst initial activity temperature >=200 DEG C.The setting position of emission reduction device is pre- in tail gas
Hot temperature is at 220 DEG C of tail gas pipeline section i.e. between heater exhaust gas three and heater exhaust gas four, tail gas pressure 0.6MPa, tail gas
230 DEG C of temperature, exhaust flow 650003/ h designs NOx content 150ppm in tail gas, synthesizes ammonia ammonia tank periodic off-gases pressure
2.1MPa, periodic off-gases group become NH3: 38%, H2: 42%, CH4~ 8%, N2~ 12%, the sum of total volume percentage composition is 100%.
The technique specifically includes the following steps:
Step 1:, by distance-transmission pressure gauge 2, the measurement of teletransmission thermometer 3 obtains pressure using the periodic off-gases 1 of synthesis ammonia tank
1.6MPa(requires to make NH by filter 4, using ratio adjusting valve 5 not less than 0.85MPa), 20 DEG C of temperature3: NOx
(volumetric concentration) controls between 1.0 ~ 1.1 ratios, and wherein NOx content has passed through online NOx measuring instrument 21 and measured, system meter
Calculate proportional quantity after provide corresponding automatic regulating valve position, by periodic off-gases flowmeter 20 measure after, by check-valves 6, then into
Enter mixer 7.
It, will wherein one step 2: exhaust pipe 8 of No. four preheaters of orthonitric acid device exhaust to tail gas preheater three times
Segment pipe is transformed into mixer 7, and through distance-transmission pressure gauge 9, teletransmission thermometer 10, online NOX measuring instrument 21 measures its tail gas respectively
After pressure 0.75MPa, 220 DEG C of temperature, NOx content, tail gas is adequately mixed with periodic off-gases after mixer 7, is anti-
Sufficient preparation should have been carried out.
Step 3: by reactor catalyst upper bed layer 12, catalyst lower bed layer 13, catalysis is passed through after reactor 11
The reaction gas of agent lower bed layer 13 passes through cross over pipe 14, and reactor 7 is entered after converging with the reaction gas by catalyst upper bed layer 12
Outlet, with the raising of reactor catalyst bed temperature, 19 value of feedback of reaction bed temperature meter under normal produce load
Elimination nitrogen oxides can be met by reaching the lasting progress of 228 DEG C or so reactions.7 front and back pressure difference of reactor is surveyed by teletransmission differential manometer 15
Master control room monitoring is measured and be sent to, nitric acid system is impacted to prevent pressure difference is excessive.
Step 4: tail gas eventually arrives at discharge outlet 16 after each heat exchanger, a sample tap 17 is opened on discharge outlet 16,
By the NOx of 18 precise measurement sample tap 17 of on-line measurement instrument, meet newest industrial discharge standard, finally leads to analysis result
It crosses signal wire and is sent to master station.
After emission reduction, NOx content in tail gas it is minimum can≤25ppm, for emission reduction rate up to 83%, the discharge value after emission reduction is far low
In the relevant emission standards of country.In terms of device year runing time 8000 hours, it is possible to reduce about 130 tons of NOx emission.It adopts simultaneously
About 70 tons of liquefied ammonia can be saved every year with periodic off-gases substitution gas ammonia, while reducing about 24 ten thousand stere of ammonia tank periodic off-gases discharge amount.
Embodiment 2:
A kind of nitric acid tail gas denitrating technique, for high pressure dust technology process tail gas, in selection high-temperature selective reducing catalyst
In the case of, selective reduction catalyst initial activity temperature >=360 DEG C.The setting position of emission reduction device is laggard swollen in tail gas heating
Before swollen machine, the tail gas pipeline section of typical temperature >=380 DEG C, tail gas pressure 0.6MPa, 380 DEG C of exhaust temperature, exhaust flow
45000Nm3/ h designs NOx content 250ppm in tail gas, synthesizes ammonia ammonia tank periodic off-gases pressure 2.1MPa, and periodic off-gases group becomes NH3:
40%, H2: 38%, CH4~ 8%, N2~ 14%, the sum of total volume percentage composition is 100%.
The technique specifically includes the following steps:
Step 1:, by distance-transmission pressure gauge 2, the measurement of teletransmission thermometer 3 obtains pressure using the periodic off-gases 1 of synthesis ammonia tank
1.0MPa(requires to make NH by filter 4, using ratio adjusting valve 5 not less than 0.8MPa), 30 DEG C of temperature3: NOx (body
Product concentration) control is between 1.0 ~ 1.1, and wherein NOx content has passed through online NOx measuring instrument 21 and has measured, system-computed proportion
Corresponding automatic regulating valve position is provided after amount, after measuring by periodic off-gases flowmeter 20, by check-valves 6, subsequently into mixing
Device 7.
Step 2: the exhaust pipe 8 after orthonitric acid device exhaust superheater, wherein will be transformed into mixer by a segment pipe
7, through distance-transmission pressure gauge 9, teletransmission thermometer 10, online NOx measuring instrument 21 measures its tail gas pressure 0.6MPa, temperature 380 respectively
DEG C, after NOx content, tail gas is adequately mixed with periodic off-gases after mixer 7, has carried out sufficient preparation for reaction.
Step 3: by reactor catalyst upper bed layer 12, catalyst lower bed layer 13, catalysis is passed through after reactor 11
The reaction gas of agent lower bed layer 13 passes through cross over pipe 14, and reactor 7 is entered after converging with the reaction gas by catalyst upper bed layer 12
Outlet, with the raising of reactor catalyst bed temperature, 19 value of feedback of reaction bed temperature meter under normal produce load
Elimination nitrogen oxides can be met by reaching the lasting progress of 390 DEG C or so reactions.7 front and back pressure difference of reactor is surveyed by teletransmission differential manometer 15
Master control room monitoring is measured and be sent to, nitric acid system is impacted to prevent pressure difference is excessive.
Step 4: tail gas eventually arrives at discharge outlet 16 after each heat exchanger, a sample tap 17 is opened on discharge outlet 16,
By the NOx of 18 precise measurement sample tap 17 of on-line measurement instrument, meet newest industrial discharge standard, finally leads to analysis result
It crosses signal wire and is sent to master station.
After emission reduction, NOx content in tail gas it is minimum can≤25ppm, for emission reduction rate up to 90%, the discharge value after emission reduction is far low
In the relevant emission standards of country.In terms of device year runing time 8000 hours, it is possible to reduce about 184 tons of NOx emission.It adopts simultaneously
About 91 tons of liquefied ammonia can be saved every year with periodic off-gases substitution gas ammonia, while reducing about 30 ten thousand stere of ammonia tank periodic off-gases discharge amount.
It is elaborated although the present invention has passed through specific embodiment, this profession ordinary skill
Personnel should be understood that made on this basis without departing from any form of claims and the variation of details,
Belong to invention which is intended to be protected.
Claims (7)
1. a kind of nitric acid tail gas denitrating technique, it is characterised in that the following steps are included:
Step 1: the periodic off-gases from synthesis ammonia tank to be removed to the particulate matter of entrainment through filter, make its pressure to height through decompression
In nitric acid tail gas 0.2 ~ 0.5MPa of pressure, after flowmeter measures, made by control and regulation valve control periodic off-gases flow therein
NOx flow reaches certain ratio in ammonia flow and nitric acid tail gas, enters mixer through check-valves；
Step 2: nitric acid tail gas measures pressure and temperature through distance-transmission pressure gauge and teletransmission thermometer respectively, and is surveyed by online NOx
After measuring instrument NOx content, tail gas flows through mixer, is tentatively mixed with the periodic off-gases sprayed by rake injector, then through two-stage
Filler mixer, is sufficiently mixed tail gas with periodic off-gases；
Step 3: mixed tail gas flows up and down respectively by catalyst upper bed layer, catalyst lower bed layer, under
The reaction gas of bed enters reactor outlet after cross over pipe converges, and with the progress of reaction, reaction bed temperature is gradually
It improves；Hydrogen therein is reacted with oxygen generates water vapour, and ammonia and reaction of nitrogen oxides generate nitrogen and water；
Step 4: tail gas eventually arrives at discharge outlet after each heat exchanger, expanding machine acting, pass through the sampling on discharge outlet
Mouthful, whether the NOx through on-line measurement instrument precise measurement sample tap meets newest industrial discharge standard.
2. nitric acid tail gas denitrating technique as described in claim 1, it is characterised in that: on-line measurement instrument precise measurement in the 4th step
Result master station be sent to by signal wire analyzed, to increase and decrease periodic off-gases flow.
3. nitric acid tail gas denitrating technique as described in claim 1, it is characterised in that: the synthesis ammonia tank in the first step speeds to put
Gas is from synthesis ammonia ammonia tank, and wherein the pressure 2.1MPa of periodic off-gases, forms the NH in terms of volumn concentration3: 38 ~ 40%, H2: 38 ~
45%, CH4~ 8%, N2~ 14%, the sum of total volume percentage composition is 100%.
4. nitric acid tail gas denitrating technique as described in claim 1, it is characterised in that: in the first step, after adjusting flow
It is sufficiently mixed in periodic off-gases and tail gas mixer, makes the NH in gaseous mixture3: the volumetric concentration ratio of NOx is 1.0 ~ 1.1.
5. nitric acid tail gas denitrating technique as described in claim 1, it is characterised in that: in the mixer of the second step, speed to put
Gas ingress pipe protrudes into exhaust pipe, and the branch pipe of several rows sidewards, branch tube spacing 100mm, branch pipe tail are welded on ingress pipe
End and pipeline are welded and fixed securely with fixed block, and two side directions of vertical exhaust gas flow direction offer the spray of Ф 1mm on branch pipe(tube)
Hole, spray orifice spacing 50mm, i.e. rake spray orifice, ejects periodic off-gases by spout；Mixing chamber uses stainless steel structured packing
Layer replaces installation with two sections of blank pipe sections；Stainless steel structured filling material layer is two groups, and stainless steel structured packing is fixed on tube wall, is filled out
Material arrangement angle layer successively misplaces alternating, and vertical with airflow direction.
6. nitric acid tail gas denitrating technique as described in claim 1, it is characterised in that: the periodic off-gases in the third step are as de-
Nitre agent is injected into high temperature nitric acid tail gas Benitration reactor, effective component ammonia in periodic off-gases, at a certain temperature, through catalyst
The nitrogen oxides in tail gas is decomposed under effect the nitrogen and water for generating no pollution to the environment.
7. nitric acid tail gas denitrating technique as described in claim 1, it is characterised in that: in the third step, with reaction into
Row, reaction bed temperature is gradually increased, and for double pressing technology nitric acid tail gas, 3 DEG C ~ 8 DEG C of usual catalyst bed temperature rise i.e.
Achieve the effect that make nitrogen oxides in nitric acid tail gas to decolourize.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111437705A (en) * | 2019-12-26 | 2020-07-24 | 江苏乐竹环保科技有限公司 | Method for treating nitric acid tail gas |
| CN114191962A (en) * | 2021-11-30 | 2022-03-18 | 海澜智云科技有限公司 | Industrial internet-based optimized process for preparation process of nitric acid in coal chemical industry |
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|---|---|---|---|---|
| US6503472B1 (en) * | 1998-05-14 | 2003-01-07 | Calgon Carbon Corporation | Method for removal of nitrogen oxides from gaseous streams by cayalytic carbon in the presence of ammonia |
| CN202762311U (en) * | 2012-08-22 | 2013-03-06 | 东方电气集团东方锅炉股份有限公司 | Spraying device for selective catalytic reduction (SCR) denitration reducing agent |
| CN103831015A (en) * | 2014-03-05 | 2014-06-04 | 杭州龙山化工有限公司 | Dual pressure nitric acid tail gas NOx removing device and denitrification method thereof |
| CN205868042U (en) * | 2016-08-01 | 2017-01-11 | 四川金象赛瑞化工股份有限公司 | Still crude gas and tail gas blender |
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2018
- 2018-11-07 CN CN201811319340.5A patent/CN109173639A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6503472B1 (en) * | 1998-05-14 | 2003-01-07 | Calgon Carbon Corporation | Method for removal of nitrogen oxides from gaseous streams by cayalytic carbon in the presence of ammonia |
| CN202762311U (en) * | 2012-08-22 | 2013-03-06 | 东方电气集团东方锅炉股份有限公司 | Spraying device for selective catalytic reduction (SCR) denitration reducing agent |
| CN103831015A (en) * | 2014-03-05 | 2014-06-04 | 杭州龙山化工有限公司 | Dual pressure nitric acid tail gas NOx removing device and denitrification method thereof |
| CN205868042U (en) * | 2016-08-01 | 2017-01-11 | 四川金象赛瑞化工股份有限公司 | Still crude gas and tail gas blender |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111437705A (en) * | 2019-12-26 | 2020-07-24 | 江苏乐竹环保科技有限公司 | Method for treating nitric acid tail gas |
| CN114191962A (en) * | 2021-11-30 | 2022-03-18 | 海澜智云科技有限公司 | Industrial internet-based optimized process for preparation process of nitric acid in coal chemical industry |
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Application publication date: 20190111 |