CN1294080C - Process for removing ammonia from an ammonia-containing gas stream - Google Patents

Process for removing ammonia from an ammonia-containing gas stream Download PDF

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Publication number
CN1294080C
CN1294080C CNB038117568A CN03811756A CN1294080C CN 1294080 C CN1294080 C CN 1294080C CN B038117568 A CNB038117568 A CN B038117568A CN 03811756 A CN03811756 A CN 03811756A CN 1294080 C CN1294080 C CN 1294080C
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ammonia
urea
described method
flow
ammonium salt
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CN1656020A (en
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A·J·比尔曼斯
F·H·M·布伊蒂克
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DSM IP Assets BV
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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
    • B01D53/58—Ammonia
    • 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
    • B01D53/73—After-treatment of removed components
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
    • C01C1/00—Ammonia; Compounds thereof
    • C01C1/02—Preparation, purification or separation of ammonia
    • C01C1/026—Preparation of ammonia from inorganic compounds
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
    • C01C1/00—Ammonia; Compounds thereof
    • C01C1/02—Preparation, purification or separation of ammonia
    • C01C1/12—Separation of ammonia from gases and vapours
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

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  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Environmental & Geological Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Biomedical Technology (AREA)
  • General Health & Medical Sciences (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Treating Waste Gases (AREA)
  • Fertilizers (AREA)
  • Gas Separation By Absorption (AREA)
  • Removal Of Specific Substances (AREA)

Abstract

Process for removing ammonia from an ammonia-containing gas stream by converting the ammonia in the ammonia-containing gas stream with an organic acid into an ammonium salt, characterized in that the obtained ammonium salt is contacted, at elevated temperature, with a peroxide.

Description

From contain ammonia flow, remove the method for deammoniation
The present invention relates to a kind of is that ammonium salt removes deammoniation (NH from contain ammonia flow by adopting organic acid to transform the ammonia that contains in the ammonia flow 3) method.
These class methods for example are disclosed among the US-A-4424072.In the 10th hurdle of this patent specification, the method for removing deammoniation is disclosed from the effusive air-flow in urea plant prilling tower top, be by this air-flow is contacted with a kind of non-volatile, dilute acid soln, like this, this NH 3Be absorbed.According to US-A-4424072, the non-volatile acid solutions that is used for the urea plant prilling tower comprises mineral acid such as phosphoric acid, sulfuric acid and nitric acid and organic acid such as citric acid, oxalic acid and similar non-volatile organic acid.According to US-A-4424072, this contains ammonia flow and is discharged in the air, but normally, the ammonia flow that contains of leaving this prilling tower is to be cycled back among the urea production process.
Using these sour shortcomings is can be betided in the final product (being urea at this) by the pollution that ammonium salt causes, this pollution is undesirable.For instance, the ammonium salt in the urea can cause this urea to be not suitable for preparing trimeric cyanamide usually.The separation processing (for example as by product) of these ammonium salts needs cost money and energy, perhaps often causes environmental problem.
Have found that aforesaid shortcoming can adopt a kind of method to be eliminated, thus, prepared ammonium salt at high temperature contacts with superoxide.
Particularly, the invention discloses a kind of method that contains ammonia flow ammonia that is used for removing, is that the ammonia that contains in the ammonia flow by the conversion of employing organic acid is ammonium salt, it is characterized in that making the ammonium salt of acquisition contacting with superoxide under the temperature between 80-400 ℃.
In the present invention, organo-peroxide and/or hydrogen peroxide can be used as superoxide.Operable organo-peroxide example is benzoyl peroxide, methyl ethyl ketone peroxide, peroxyester, peroxy dicarbonate salt and dialkyl peroxide.This superoxide can be used as it is, and perhaps uses with the solution that is dissolved in one or more solvents.Water can be used as solvent.The mixture of different superoxide also can adopt.Preferably, use hydrogen peroxide as this superoxide.
The method of the invention is at high temperature carried out.High temperature herein is the temperature that is illustrated between 80-400 ℃.The temperature between 100-300 ℃ that contacts preferably of this ammonium salt and this superoxide is carried out, and preferred especially temperature is at 150-250 ℃.
The use organic acid transforms the ammonia in the ammonium salt.Multiple different acid can be used as this organic acid.Preferred formic acid, oxalic acid and/or the citric acid of using is preferably oxalic acid especially.
These organic acid ammonium salts employing superoxide are converted into and contain NH 3, CO 2And H 2The mixture of O.The integral part ground of these mixtures is to be determined by used acid.The advantage of the method for the invention is that formed material for example can easily reprocessed in the urea technique.
The present invention can be applicable to may produce among the process plant that contains ammonia flow arbitrarily.The example of this class process plant (wherein can produce this class air-flow) is the factory that is used to produce urea, trimeric cyanamide and ammonia.These many class air-flows all are the refuse air-flows.Preferably, the ammonia flow that contains in the method for the present invention is the tail gas that is derived from urea plant.Multiple different production method can be applicable to production urea practically, as is disclosed in the method in Uhlmann ' s Encyclopedia of IndustrialChemistry Vol.A27 (1996) the 333-354 pages or leaves.At first, at the conventional high pressure urea Workshop Production of what is called urea,, these methods substitute but being applied to the method for so-called urea stripper plant after nineteen sixty.
The embodiment that a kind of frequent employing gas stripping process is used to produce urea is StamicarbonCO 2Gas stripping process, it is disclosed in Uhlmann ' s Encyclopedia of IndustrialChemistry Vol A27 (1996) the 344-346 pages or leaves.The gaseous mixture that makes in this stripping is handled, with the ammonia that this method needs, in high-pressure carbamate condenser, major part obtains condensation and absorption, therefore, just can be transported to the synthetic district that is used to form urea at the carboxylamine ammonia that draws formation.
This high-pressure carbamate condenser for example, can be designed as falling liquid film condenser or what is called and soaks sliding condenser, described in NL-A-8400839.This submergence condenser can level or vertical the placement.
Adopting described Stamicarbon CO 2In the urea plant of stripping process, in order to reclaim the especially purpose of ammonia, the gaseous mixture that in this reactor, produces, it is made up of rare gas element, ammonia and carbonic acid gas, adopts a kind of aqueous solution that it is washed in high-pressure scrubber.In this high-pressure scrubber, it produces a kind of inert gas, and it is still polluted by Trace Ammonia.Before this inert gas can be discharged in the atmosphere, this ammonia need be removed from described inert gas.From this inert gas, remove deammoniation, can adopt the method for the invention to carry out.Therefore, contain NH in the inventive method 3Air-flow can be the tail gas of urea scrubber.
In other urea production process, also usually exist this purging gas stream of purging gas stream of condensable gases not can adopt the present invention to remove wherein ammonia, make it to reach extremely low residual concentration.
In this procedure, leave the urea synthesis solution of urea reactors, be converted into urea melt.At this,, also produce the air-flow that its ammonia need be removed when condensation of gas with when being absorbed.Under the effect of cooling/dry air, this urea melt is converted into urea pellets or granule in cooling/drying installation.The example of this class cooling/drying installation is prilling tower and tablets press.Tablets press often is fluidized-bed or spouted bed granulators.Drum type or dish-type granulators also can adopt.This cooling/dry air is discharged into scrubber as air-flow from this cooling/drying installation, to remove the Trace Ammonia that exists in this air.Before these exhaust gas stream were discharged in the environment, all these exhaust gas stream all can adopt the inventive method to purify.For example, the ammonia flow that contains in the inventive method can be to be derived from the prilling tower of urea plant or the air-flow of tablets press.Another kind of ammonia emission source is a chimney, and the spring touch-safe valve of plant items is connected thereto.When too high pressure threat takes place therein (it will cause unsafe state), spring touch-safe valve is used for from the plant items relief pressure.
The exhaust gas stream of urea plant contains ammonium formiate usually.This ammonium formiate for example, is formed by ammonia and formaldehyde when oxygen exists.Formaldehyde is used as granulation aid in urea plant, and is used for preventing or being reduced in the formation of dust in the granulation process.
The also available superoxide of this ammonium formiate is converted into and contains NH 3, CO 2And H 2The mixture of O.Preferably, use hydrogen peroxide as superoxide.The NH that forms 3, CO 2And H 2O is sent back to is used for urea production.
When producing trimeric cyanamide, operable method has: low voltage operated method, i.e. gas phase process, or high top pressure operation method, i.e. liquid phase process.At Nitrogen No.228, the 43-51 page or leaf in July, 1997-8 month, has provided the summary of present melamine processes.In gas phase and liquid-phase melamine processes, the purge stream of desorption column (therein, ammonia is recovered) is that a kind of ammonia is discharged into may originate in the atmosphere.At this, the inventive method also can be used well.
Exhaust gas stream in melamine plants also often contains ammonium formiate.This comes from the HCN that exists and the saponification of water when high temperature.At this, the also available superoxide of ammonium formiate is converted into and contains NH 3, CO 2And H 2The mixture of O.
Such exhaust gas stream is also contained in the workshop that is used for for example producing ammonia and ammonium nitrate, before this class logistics can be discharged, and need be from wherein removing deammoniation.The inventive method also can advantageously be applied to this kind situation.
The inventive method also can be used for improving and the existing workshop of optimization.
By means of accompanying drawing and example, the present invention will obtain more detailed explanation.
Figure 1 shows that the synoptic diagram that wherein adopts new urea plant part of the present invention.At this, 1 expression (fluidized-bed) tablets press, urea melt 3 is imported in this tablets press, and is converted into the urea granule with air logistics 8.This urea granule of temperature still flows through 4 and arrives product water cooler 2, and adopts air logistics 8 to make its further cooling once more.The refrigerative granule flows through 5 and arrives product sieve 6, and at this place, the urea granule is divided into three road product logistics.One tunnel logistics 7 is made up of the product of wishing size, and two route oversized dimensions and not enough size product are formed in addition.Coarse product stream is pulverized and is sent back to this tablets press with thin product logistics through 9.The tail gas of this tablets press with the tail gas of this reactor product cooler, flows to scrubber 10, and at this place, by means of the water by 23 supplies, the urea dust in this tail gas is eliminated.This off-gas stream also can be handled in isolating washing device.The urea dust that is removed is sent back among this technology through pipeline 22.The off-gas stream of having removed urea dust is sent back to scrubber 11, and at this place, ammonia is removed from this tail gas, and is converted into ammonium oxalate under the rare oxalic acid solution by 12 supplies helps.At the washings that contains ammonium oxalate of this acquisition, part is sent back in 11 via 13, part via 14 and interchanger 15 be transported to ammonium oxalate decomposer 16.Removed the tail gas of deammoniation, from this technology, be removed via 19.In ammonium oxalate decomposer 16, ammonium oxalate at high temperature under hydrogen peroxide and the help by 18 vapor supplied by 17 supplies, is converted into NH 3, CO 2And H 2O.This NH that contains 3, CO 2And H 2The air-flow 20 of O is sent back among the urea technique.After the additional processing in the waste water zone of this urea plant randomly, waste water is removed from this workshop via 21.
Figure 2 shows that the synoptic diagram of new urea plant part as shown in Figure 1.But, in Fig. 2, be derived from the part of the air-flow of scrubber 10, be cycled back to this tablets press via described urea melt raw material.By this way, ammonia level is built up in tablets press 1 and scrubber 10, and a kind of have a high relatively NH 3The purge stream of concentration just can be sent back to scrubber 11 from it, and is removed from technology of the present invention.
Figure 3 shows that the synoptic diagram of existing urea workshop part, wherein, existing workshop is optimized by adopting the present invention.In urea plant, (it is by unconverted NH for reactor tail gas 3And CO 2Form with rare gas element), in high-pressure scrubber, adopt the rare ammonium carbamate solution that makes at the urea retrieving arrangement, it is washed.Obtain a kind of tail gas from this high-pressure scrubber, in existing workshop, it is to be supplied to resorber 1, and most of ammonia wherein is removed from described off-gas stream.In the present invention, the inert purge air-flow that obtains in 1 is sent in the off-gas scrubber 3 of new installation via 2, and wherein, via a kind of rare oxalic acid solution of 5 metering inputs, ammonia is converted into ammonium oxalate.Removed the inert purge air-flow of deammoniation, from described technology, be removed via 4.Described rare ammonium oxalate solution from 3, part is sent back to off-gas scrubber 3, locates it as washings at this.The rest part of the described ammonium oxalate solution from 3 is transported in the existing urea splitter 7 of urea plant Waste Water Treatment via 6.Before being transported to urea decomposer 7, this ammonium oxalate solution with by 8 the supply hydrogen peroxide mix.The hydrogen peroxide of this supply also can directly be fed in the urea decomposer 7.This NH that contains from 7 3, CO 2And H 2The air-flow of O is sent back among this urea technique via 9.
Example 1
A kind of fluid bed granulation unit that is derived from urea plant contain ammonia flow, at room temperature adopt the oxalic acid aqueous solution of about 3wt%, it is washed.Obtain containing in a kind of per 1000 gram water the solution of 45 gram ammonium oxalate.With this solution of the 250 grams (ammonium oxalate in the water=4.5wt%) be transported in the 500ml reactor.Improve the content temperature to 200 ℃ in the reactor, then in this reactor, introduce a kind of solution that obtains in the 25 gram water that is dissolved in by 3 gram hydrogen peroxide.Therefore this ammonium oxalate solution is reduced to 1.5wt%.Afterwards, in this reactor, introduce a kind of solution that obtains in the 25 gram water that is dissolved in by 3 gram hydrogen peroxide once more.This ammonium formiate concentration has been reduced to 0.05wt% now.In this reactor, introduce a kind of solution that obtains in the 25 gram water that is dissolved in by 3 gram hydrogen peroxide for the third time.Ammonium oxalate solution is reduced to 0.0009wt%.
Example 2
A kind of inert purge that is derived from the urea plant resorber contain ammonia flow, at room temperature adopt a kind of 50ppm aqueous formic acid, it is washed.This solution of 250ml is transported in the 500ml reactor.Improve the content temperature to 143 ℃ in the reactor, then in this reactor, introduce a kind of solution that obtains in the 25 gram water that is dissolved in by the 27.5mg hydrogen peroxide.Therefore this ammonium formiate concentration is reduced to 30ppm.Afterwards, in this reactor, introduce a kind of solution that obtains in the 25 gram water that is dissolved in by the 27.5mg hydrogen peroxide once more.This ammonium formiate concentration has been reduced to 9.3ppm now.In this reactor, introduce a kind of solution that obtains in the 25 gram water that is dissolved in by the 27.5mg hydrogen peroxide for the third time.Ammonium oxalate solution is reduced to 0.9ppm.

Claims (12)

1. being used for removing the method that contains ammonia flow ammonia, is that the ammonia that contains in the ammonia flow by the conversion of employing organic acid is ammonium salt, it is characterized in that making the ammonium salt of acquisition to contact with superoxide under the temperature between 80-400 ℃.
2. the described method of claim 1 is characterized in that using organo-peroxide and/or hydrogen peroxide as superoxide.
3. the described method of claim 1 is characterized in that using hydrogen peroxide as superoxide.
4. each described method of claim 1-3, the conversion that it is characterized in that described ammonium salt is to carry out under the temperature between 100-300 ℃.
5. each described method of claim 1-3, the conversion that it is characterized in that described ammonium salt is to carry out under the temperature between 150-250 ℃.
6. the described method of claim 1 is characterized in that using formic acid, oxalic acid and/or citric acid as organic acid.
7. the described method of claim 1 is characterized in that using oxalic acid as organic acid.
8. the described method of claim 1 is characterized in that described ammonium salt is converted into a kind of NH of containing 3, CO 2And H 2The mixture of O.
9. the described method of claim 8 is characterized in that formed NH 3, CO 2And H 2O reprocesses in urea technique.
10. the described method of claim 1 is characterized in that the described ammonia flow that contains is the tail gas that is derived from urea plant.
11. the described method of claim 10 is characterized in that the described ammonia flow that contains is to be derived from the prilling tower of urea plant or the air-flow of tablets press.
12. the described method of claim 10 is characterized in that the described NH of containing 3Air-flow is the tail gas of urea scrubber.
CNB038117568A 2002-05-23 2003-05-06 Process for removing ammonia from an ammonia-containing gas stream Expired - Fee Related CN1294080C (en)

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NL1020665A NL1020665C2 (en) 2002-05-23 2002-05-23 Process for removing ammonia from an ammonia-containing gas stream.
NL1020665 2002-05-23

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CN1294080C true CN1294080C (en) 2007-01-10

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AR (1) AR040041A1 (en)
AU (1) AU2003224520A1 (en)
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MY (1) MY142787A (en)
NL (1) NL1020665C2 (en)
WO (1) WO2003099721A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105709579A (en) * 2016-04-05 2016-06-29 紫金矿业集团股份有限公司 Technology and equipment for recovering non-condensable gas in evaporation process of gold smelting waste water

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CN101284169B (en) * 2008-05-14 2011-05-18 中国科学技术大学 Ammonia decontamination agent and preparation method thereof
EP2192099A1 (en) 2008-11-28 2010-06-02 Uhde Fertilizer Technology B.V. Urea granulation process with an acidic scrubbing system and the subsequent integration of ammonium salt into urea granules
ES2423191T3 (en) 2008-12-12 2013-09-18 Thyssenkrupp Uhde Gmbh Elimination of ammoniacal nitrogen, ammonium nitrogen and urea nitrogen from the waste air of ammonia and urea production plants, by oxidation with solutions containing hypochlorite
IT1395127B1 (en) * 2009-07-30 2012-09-05 Saipem Spa PROCEDURE FOR THE RECOVERY OF AMMONIA FROM A GAS CURRENT
EP2301917A1 (en) 2009-09-16 2011-03-30 Stamicarbon B.V. Removal of urea and ammonia from exhaust gases
EP2662349A1 (en) 2012-05-08 2013-11-13 Uhde Fertilizer Technology B.V. Urea granulation process with scrubbing system
EP2746244A1 (en) 2012-12-21 2014-06-25 Uhde Fertilizer Technology B.V. Method for reducing the visible downwind detached plume opacity
CN107126826A (en) * 2017-04-10 2017-09-05 天津凯赛特科技有限公司 Ammonia-contained tail gas treating device and method in prepared by a kind of soda ash
CN107115762A (en) * 2017-04-21 2017-09-01 福建皓尔宝新材料科技有限公司 A kind of method that grape wine composition removes ammonia in room air in real time online
CN108503532A (en) * 2018-05-14 2018-09-07 衡阳师范学院 A kind of processing method for the by-product tail gas preparing Zassol
NL2029462B1 (en) 2020-10-19 2022-06-08 Lenntech B V Process for acid washing of a gas comprising ammonia

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Cited By (1)

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Publication number Priority date Publication date Assignee Title
CN105709579A (en) * 2016-04-05 2016-06-29 紫金矿业集团股份有限公司 Technology and equipment for recovering non-condensable gas in evaporation process of gold smelting waste water

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CA2483648A1 (en) 2003-12-04
CN1656020A (en) 2005-08-17
MY142787A (en) 2010-12-31
NL1020665C2 (en) 2003-11-25
WO2003099721A1 (en) 2003-12-04
AU2003224520A1 (en) 2003-12-12
AR040041A1 (en) 2005-03-09

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