CN102635427A - Sectional type ammonia generating device for discomposing solid urea - Google Patents
Sectional type ammonia generating device for discomposing solid urea Download PDFInfo
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- CN102635427A CN102635427A CN2012101222679A CN201210122267A CN102635427A CN 102635427 A CN102635427 A CN 102635427A CN 2012101222679 A CN2012101222679 A CN 2012101222679A CN 201210122267 A CN201210122267 A CN 201210122267A CN 102635427 A CN102635427 A CN 102635427A
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- urea
- isocyanic acid
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- 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
Abstract
The invention belongs to the field of cleaning of the tail gas of a diesel engine, and particularly relates to a sectional type ammonia generating device for discomposing solid urea, wherein the device can be used for treating the tail gas of a motor vehicle. The device consists of an ammonia reaction tank, an urea pyrolysis catalysis device and an isocyanic acid hydrolysis catalysis device, which are sequentially arranged in the ammonia reaction tank according to an airflow direction; the front end of the ammonia reaction tank is provided with an urea inlet, the back end of the ammonia reaction tank is provided with an ammonia outlet, and a steam transporting conduit is arranged nearby the urea inlet; the urea pyrolysis catalysis device is formed by a multi-layer wire mesh carrier which is coated with a glass coating layer SiO2-Al2O3 and loaded with a urea pyrolysis catalyst Pt, Ag or Pd; and the isocyanic acid hydrolysis catalysis device is formed by a metal honeycomb carrier coated with the isocyanic acid hydrolysis catalyst SiO2-Al2O3. Due to the urea pyrolysis catalyst and the isocyanic acid hydrolysis catalyst, the device is used for catalyzing each stage of ammonia generation by ammonia, so that the reaction temperature can be reduced, the reaction can be accelerated, and the energy can be saved.
Description
Technical field
The invention belongs to the diesel engine vent gas field of purification, be specifically related to a kind of segmented solid urea decomposition ammonia-preparing device, this device can be applicable to the motor-driven vehicle gas disposal.
Technical background
NO in the automotive emission pollutant
XAccount for global NO
XPollute 20% of total amount, pollute in order to eliminate these, satisfy the exhaust emission standard of increasingly stringent, the exhaust gas from diesel vehicle post-processing technology becomes the technology that present people need development badly.At present, ammonia selects catalytic reduction technology (SCR denitration technology) to be considered to the most effectively remove NO in the motor-vehicle tail-gas
XTechnology.The SCR denitration technology is under the condition of oxygen enrichment, under the effect of catalyzer, utilizes NH
3As reducing agent, with the NO in the tail gas
XFollowing redox reaction takes place:
4NH
3+4NO+O
2＝4N
2+6H
2O
The common employed raw material of ammonia preparation system is liquefied ammonia and ammoniacal liquor; Be to exist with the liquid state of ammonia and the form of hydrate; As long as heating can obtain ammonia through evaporation or decomposition process; But because ammonia is poisonous, be difficult for storing, in transportation process, in a single day reveal and to cause great security incident.
In recent years, people develop liquid urea gradually and select the catalytic reduction technology, use the reducing agent of urea liquid as the SCR reaction, hope that preparing ammonia through following two reactions directly is applied in the SCR reaction:
(1) pyrolytic reaction of urea, temperature are higher than 152 ℃:
H
2N-CO-NH
2(s)＝＝NH
3(g)+HNCO(g)
(2) hydrolysis reaction of isocyanic acid:
HNCO+H
2O＝＝NH
3(g)+CO
2(g)
But aqueous solution of urea freezes under the situation of low temperature easily, is difficult for storing; And in the aqueous solution of urea pyrolytic process,, can consume most of energy for making the water evaporation in the urea.Urea can form sediments in decomposition process simultaneously, is deposited on SCR catalyst converter surface, makes catalysqt deactivation easily.Research contents among Catalysis B:Environmental70 (2007) 91-99 shows the NO of isocyanic acid hydrolyst in running into tail gas
XThe time catalyst surface can deposit nitrate, cause the hydrolyst inactivation.
Solid urea selects catalytic reduction technology (SSCR) to utilize solid urea to produce ammonia; Get into SCR catalyst converter reducing NOx; Both inherit the plurality of advantages of liquid SCR technology, solved a series of problems of liquid SCR again, so the SSCR technology had had huge exploitation value and market application foreground.
Summary of the invention
The object of the present invention is to provide a kind of segmented solid urea decomposition ammonia-preparing device and method that is used for motor-vehicle tail-gas denitration SSCR system.
Device of the present invention is a kind of urea ammonia-preparing device that can be suitable in the exhaust gas from diesel vehicle post-processing technology, adopts the method for chemical catalysis, under the effect of water, urea decomposition is become carbon dioxide and ammonia.The present invention utilizes urea pyrolysis catalytic agent (Pt, Ag or Pd) to quicken the pyrolytic process of urea, the urea fast pyrogenation is become to contain the mixed gas of ammonia and isocyanic acid: H
2N-CO-NH
2(s)=NH
3(g)+HNCO (g); The isocyanic acid gas that generates is at isocyanic acid hydrolyst (solid-acid catalyst SiO
2-Al
2O
3) catalysis under, generate ammonia and carbon dioxide: HNCO+H with steam reaction
2O=NH
3(g)+CO
2(g).
Along with expanding economy, national automobile pollution continues to increase, and the exhaust emissions amount increases day by day, and the nitrogen oxide of removing in the tail gas becomes the technological major requirement of exhaust aftertreatment, and the invention is just meeting this requirement.
Urea pyrolysis catalytic device 3 and isocyanic acid hydrolyzation catalysis device 6 that segmented urea decomposition ammonia-preparing device of the present invention is set in turn in the ammonia gas react jar by ammonia gas react jar 2, by airflow direction are formed; Ammonia gas react jar 2 is that internal diameter is that 5～15 centimetres, thickness are that 4～8 millimeters, length are 10～20 centimetres stainless cylinder of steel; The front end of ammonia gas react jar 2 is provided with urea material feeding mouth 1; The rear end is provided with ammonia delivery outlet 10, is provided with water vapor delivery conduit 9 (water vapor comes from vehicle exhaust) on the next door of urea material feeding mouth 1; Inboard at the ammonia gas react jar 2 of urea pyrolysis catalytic device 3 corresponding positions is provided with first Electric heating appliance 4 and first temperature transducer 5; Inboard at the ammonia gas react jar 2 of isocyanic acid hydrolyzation catalysis device corresponding position is provided with second Electric heating appliance 7 and second temperature transducer 8; Wire gaze and metal beehive carrier are weldingly fixed on retort inside.
As shown in Figure 1, ammonia gas react jar 2 is made for stainless steel material; Between 130～150 ℃, Powdered or granular urea is heated to molten through melting plant 0 through electric heating control temperature in melting plant 0 inside, is advanced in the urea pyrolysis catalytic device 3 in the ammonia gas react jar 2 by 1 injection of urea material feeding mouth; Urea pyrolysis catalytic device 3 is made up of the multiple layer metal silk screen carrier that is coated with glass coating and urea supported pyrolysis catalytic agent (Pt, Ag or Pd), the quality of glass coating and urea pyrolysis catalytic agent (Pt, Ag or Pd) and be 1～5% of wire mesh carrier quality; In glass coating and the agent of urea pyrolysis catalytic, the quality percentage composition of Pt is 0.1～0.5%, the quality percentage composition of Ag be 1～5% or the quality percentage composition of Pd be 0.1～0.5%, all the other are SiO
2And Al
2O
3The glass coating of forming, SiO in the glass coating
2The quality percentage composition is 60～80%; Urea pyrolysis catalytic device 3 is through heating around being arranged at the first inboard heating equipment 4 of ammonia gas react jar, and first heating equipment 4 is an electromagnetic heating coil, and electromagnetic heating coil adopts enameled cable to process, the individual layer tiling; The number of turn is between 40～60, the diameter 2～6mm of every enameled cable.
First heating equipment 4 is controlled through instruction call wire 401 by electrical adjustment and control unit ECU, and ECU can select EDC7-6DL2 for use, and can select the ECU of different model according to actual vehicle situation for use.When having only ECU to assign instruction, heating equipment 4 just can begin heating.First temperature transducer 5 (can use digital temperature sensor; Fibre optic temperature sensor etc.) monitor urea pyrolysis catalytic device 3 temperature inside in real time; When temperature is lower than urea pyrolysis temperature (152 ℃) in the device; Temperature transducer sends a signal to ECU through instruction call wire 501, and ECU will be sent to first heating equipment 4 through instruction call wire 401 with feedback signal at once, makes first heating equipment 4 begin heating.When temperature was higher than predefined limiting value in the device, ECU was through the 401 control heater stop heating of instruction call wire.Whole system can make the temperature maintenance (152～400 ℃) in the urea pyrolysis temperature range in the urea pyrolysis catalytic device 3 through the mutual coordinative role between ECU and first temperature transducer 5 and first heating equipment 4.
Isocyanic acid hydrolyzation catalysis device 6 is by applying isocyanic acid hydrolyst (SiO
2-Al
2O
3) metal beehive carrier constitute isocyanic acid hydrolyst (SiO
2-Al
2O
3) quality be 1～5% of metal beehive carrier quality, the isocyanic acid hydrolyst is by SiO
2And Al
2O
3Form, wherein SiO
2The quality percentage composition be 50%～60%; Isocyanic acid hydrolyzation catalysis device 6 inside are provided with equally and are surrounded on the second inboard heating equipment 7 of ammonia gas react jar (adopting the electromagnetic heating coil heating equally) and second temperature transducer 8; All control and regulate through ECU; When the temperature in the isocyanic acid hydrolyzation catalysis device 6 is lower than 300 ℃; Second temperature transducer 8 will be sent to ECU through instruction call wire 801 with signal; ECU will heat to second heating equipment, 7 unlatching electric heating programs signal feed back through instruction call wire 701; When second temperature transducer 8 records hydrolysis device 6 inside temperatures and is higher than predefined temperature value, transmit ECU through signal and will send instruction and make second heating equipment 7 stop heating.Whole system can make the temperature maintenance (300～500 ℃) in the isocyanic acid temperature range for hydrolysis in the isocyanic acid hydrolyzation catalysis device 6 through the mutual coordinative role between ECU and second temperature transducer 8 and second heating equipment 7.
9 is the water vapor delivery conduit among the figure; Be delivered into the inner water vapor of ammonia gas react jar through urea pyrolysis catalytic device 3; Mix the back with the pyrogenous origin mixed gas that contains isocyanic acid of urea and get into isocyanic acid hydrolyzation catalysis device 6, the catalysis reaction through the isocyanic acid hydrolyst in isocyanic acid hydrolyzation catalysis device 6 of water vapor and isocyanic acid generates ammonia and carbon dioxide.Feeding the amount of the water vapor in the ammonia gas react jar and the mol ratio of the urea amount that the urea material feeding mouth gets into is 1～1.5: 1.
The metallic carrier that metal beehive carrier is selected for use in wire gaze in the urea pyrolysis catalytic device and the isocyanic acid hydrolyzation catalysis device is the Ni-Cr-Fe alloy material of high temperature resistant (700～900 ℃) sold the Beijing North Metallurgical Functional Materials Co., Ltd; Wherein the Ni mass content 35%; Cr mass content 20%; Fe mass content 45%, wire gaze aperture density is 300 orders, the metal beehive carrier aperture density is 300 orders.The diameter and the reaction device of wire gaze and metal beehive carrier are complementary, and metal beehive carrier length is 5～15 centimetres.Pt, Ag or Pd are selected in the agent of urea pyrolysis catalytic for use, and the isocyanic acid hydrolyst is selected solid-acid catalyst SiO for use
2-Al
2O
3
The pretreatment of metallic carrier (comprising wire mesh carrier and metal beehive carrier):
1) at first metal carrier-use ammoniacal liquor, hydrogen peroxide were mixed back alkali cleaning 0.5～1 hour in 5: 1: 1 by volume with the mixed solution of deionized water;
2) carried out pickling 5～10 minutes with metal carrier-use hydrochloric acid, hydrogen peroxide and after the mixed solution of deionized water mixed in 5: 1: 1 by volume then;
3) at last with metallic carrier calcination 2～5 hours under 800～900 ℃ of high temperature.
On pretreated wire mesh carrier, apply the process of urea pyrolysis catalytic agent:
1, coated glass coating on carrier on the wire gaze:
1) with distilled water be solvent, the preparation mass concentration is 5～38% nine water aluminum nitrate (Al (NO
3)
39H
2O) solution;
2) taking by weighing mass concentration is that 85～99% 1～10 milliliter of 4～20 milliliters of ethanol, distilled water and mass concentration are 0.1～0.3 milliliter in 65% nitric acid; Three kinds of solution are mixed and evenly stirring; Take by weighing the teos solution of 6～40 grams again; Pour in the mixed solution of this step with the speed of per 1 minute 3～5ml ethyl orthosilicate and powerful the stirring slowly, finally form transparent clear solutions;
3) get 10～30g step 2) solution of preparation slowly is injected in the solution of 20～40g step 1), simultaneously powerful the stirring 0.5～1 hour, ageing 8～15 hours obtains the glass coating sol solution; Pretreated wire mesh carrier was immersed in the glass coating sol solution 5～10 minutes, takes out then, use drier; Repeat to immerse, take out, dry up process 3～5 times; In air, under room temperature, utilize sorbing materials such as degreasing cotton, filter paper that wire mesh carrier was dried in the shade 2～12 hours then; At last in the baking box in air under 60 ℃～180 ℃ temperature dry 2～4 hours; With the stove cooling, take out, thereby obtain the wire mesh carrier that the surface scribbles glass coating.
2, coated catalysts on wire mesh carrier:
The wire mesh carrier that 1) will scribble glass coating immerses in the distilled water solution of nitrate of precious metal silver, platinum or palladium (the distilled water solution of preparation precious metal nitrate earlier; Concentration is: silver nitrate 5～30wt%; Palladium nitrate 1～10wt%; Platinum nitrate 1～10wt%) 5～10 minute takes out then and uses drier; Repeat above-mentioned immersion, take out, dry up process 3～5 times; In air, under room temperature, utilize sorbing materials such as degreasing cotton, filter paper that wire mesh carrier was dried in the shade 2～12 hours then; At last in the baking box in air under 60 ℃～150 ℃ temperature dry 2～4 hours; With the stove cooling, take out;
2) with above-mentioned wire mesh carrier in High Temperature Furnaces, be warmed up under 300～750 ℃ of temperature calcination 1～5 hour with stove, with the stove cooling, take out, thereby prepare the wire mesh carrier that applies the agent of urea pyrolysis catalytic.
Fig. 3, Fig. 4 are the SEM photo of the wire mesh carrier of the coating urea pyrolysis catalytic agent of preparation.Can find out that by photo the agent of urea pyrolysis catalytic is coated in the wire mesh carrier surface uniformly.
On pretreated metal beehive carrier, apply the process of isocyanic acid hydrolyst:
1) with distilled water be solvent, the preparation mass concentration is 5～38% nine water aluminum nitrate (Al (NO
3)
39H
2O) solution;
2) taking by weighing mass concentration is that 85～99% 1～10 milliliter of 4～20 milliliters of ethanol, distilled water and mass concentration are 0.1～0.3 milliliter in 65% nitric acid; Three kinds of solution are mixed and evenly stirring; Take by weighing the teos solution of 6～40 grams again; Pour in the mixed solution of this step with the speed of per 1 minute 3～5ml ethyl orthosilicate and powerful the stirring slowly, finally form transparent clear solutions;
3) get 10～30g step 2) solution of preparation slowly is injected in the solution of 40～60g step 1), simultaneously powerful the stirring 0.5～1 hour, the glass coating gel solution is processed in ageing 8～15 hours; Metal beehive carrier was immersed in the glass coating solution 5～10 minutes, take out then and use drier; Repeat above-mentioned immersion, take out, dry up process 3～5 times; In air, under room temperature, utilize sorbing materials such as degreasing cotton, filter paper that metal beehive carrier was dried in the shade 2～12 hours again; Then in the baking box in air under 60 ℃～180 ℃ temperature dry 2～4 hours; With the stove cooling, take out, obtain the surface and scribble SiO
2-Al
2O
3The metal beehive catalytic carrier of catalyzer.
Fig. 5 applies SiO for the tinsel that adopts material of the same race according to above-mentioned steps
2-Al
2O
3SEM picture behind the catalyzer is by finding out that hydrolyst evenly is coated in the sheet metal carrier surface among the figure.Patent of the present invention has following advantage:
1, apparatus of the present invention adopt segmentation structure, and this structure is effectively separated the decomposition of urea and the hydrolytic process of isocyanic acid, and the strictness control through to temperature reduces production of by-products.
2, use urea pyrolysis catalytic agent and isocyanic acid hydrolyst among the present invention, make each stage of urea system ammonia all carry out catalysis, reduce reaction temperature, the carrying out of accelerated reaction saved energy.
Description of drawings
Fig. 1: segmented solid urea decomposition ammonia-preparing device schematic representation:
Fig. 2: segmented solid urea decomposition device is applied to exhaust emissions system schema schematic representation:
Fig. 3: the SEM photo that applies the wire mesh carrier of urea pyrolysis catalytic agent;
Fig. 4: the SEM photo that applies the wire mesh carrier of urea pyrolysis catalytic agent;
Fig. 5: the SEM photo that applies the sheet metal carrier of hydrolyst.
Embodiment
For the purpose, technological scheme and the advantage that make the embodiment of the invention clearer; To combine accompanying drawing and experiment in the embodiment of the invention below; Technological scheme in the embodiment of the invention is carried out clear, intactly description; Obviously, described embodiment is the present invention's part embodiment, rather than whole embodiments.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment who is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.
Embodiment 1:
Fig. 2 representes a specific embodiments of device of the present invention, and in this scheme, urea decomposition ammonia-preparing device of the present invention is installed in exhaust gas processing device front in the exhaust emissions pipeline.
In this programme, when vehicle exhaust begins discharging, ECU opens the heating schedule of Electric heating appliances through instruction call wire 401 and 701, makes Electric heating appliance 4,7 begin heating.Device 11 is represented the steam rates meter among the figure; Can control the gas flow that gets in the ammonia gas react jar 2 through water vapor delivery conduit 9; Wherein passing through the flow size of the water vapor of steam rates meter 11 controls through ECU; Steam rates meter 11 transmits lead 111 with the steam rates value that senses through instruction and is sent to ECU, and ECU transmits lead 112 with feedback signal through instruction again and sends back steam rates meter 11, the flow of control water vapor; The flow requirements of concrete water vapor is that the staff preestablishes into ECU, according to the practical application can regulate.Urea gets into after the ammonia gas react jar 2 through urea material feeding mouth 1; At first pyrolysis on urea pyrolysis catalytic device 3; Generation contains the mixed gas of ammonia and isocyanic acid, and isocyanic acid gas mixes with the water vapor in the vehicle exhaust that is delivered in the water vapor delivery conduit 9, gets into isocyanic acid hydrolyzation catalysis device 6 jointly; Hydrolytic reactions under the effect of isocyanic acid hydrolyst on the isocyanic acid hydrolyzation catalysis device 6; Generate the mixed gas of carbon dioxide and ammonia, get in the tail gas stream through conduit 10 at last, participate in next step the SSCR denitration reaction that in 12, carries out.
Embodiment 2:
With 4.94g (Al (NO
3)
39H
2O is dissolved in the 20g distilled water and forms solution A;
With the 5.712g ethanol solution; 3 ml distilled waters; 0.2 the milliliter mass concentration is that 65% nitric acid mixes stirring; Weighing 6.7695g teos solution is again poured in the mixed solution of this step ethyl orthosilicate and powerful the stirring slowly with the speed of per 1 minute 4ml, finally form transparent clear solutions B;
B liquid is poured in the solution A with the speed of 2ml/min, constantly powerful the stirring 0.5 hour, ageing 12 hours finally forms the glass coating sol solution.
Get 5 of nickel chromium iron wire gazes, every wire gaze is that the length of side is the square of 5cm, and the wire gaze aperture is 300 orders; Carry out the pretreatment described in the summary of the invention, then wire mesh carrier is immersed in the coating sol solution of front preparation, immersed 10 minutes at every turn; Take out the back and use drier, immerse, take out, dry up process repeatedly 3 times, in air, under room temperature, utilize sorbing materials such as degreasing cotton, filter paper that it was dried in the shade 3 hours at last; Then in the baking box in air under 80 ℃ of temperature dry 3 hours; With the stove cooling, take out, obtain the wire mesh carrier that the surface scribbles glass coating.
The aqueous solution 100ml (1wt%) that gets platinum nitrate flooded above-mentioned wire mesh carrier 10 minutes, took out then and used drier; Repeat above-mentioned immersion, take out, dry up process 3 times, in air, under room temperature, utilize sorbing materials such as degreasing cotton, filter paper that it was dried in the shade 6 hours at last, in the baking box in air under 80 ℃ of temperature dry 3 hours,, take out then with the stove cooling; At last in High Temperature Furnaces; Be warmed up under 600 ℃ of temperature calcination 4 hours with stove,, take out with the stove cooling; Thereby prepare the wire mesh carrier that applies the agent of urea pyrolysis catalytic, the quality of glass coating and urea pyrolysis catalytic agent (Pt) and be 3% of wire mesh carrier quality; In glass coating and urea pyrolysis catalytic agent (Pt), the quality percentage composition of each component is platinum 0.5%, silica 74.75%, aluminium sesquioxide 24.75%.
Table 1 is under 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃ temperature; Through comprehensive thermal analyzer STA409PC Luxx measure at the wire mesh carrier that contains above-mentioned coated catalysts and do not contain under the effect of wire mesh carrier of coated catalysts; The transformation efficiency that urea obtains through the measurement Mass Calculation at each temperature spots; Following table shows urea under the catalysis of the wire gaze of coated catalysts, and urea has all improved at the transformation efficiency of each temperature spots.
Table 1: urea transformation efficiency
Embodiment 3:
With 14g Al (NO
3)
39H
2O is dissolved in the 40g distilled water and forms solution A;
With the 5.712g ethanol solution; 3 ml distilled waters; 0.2 the milliliter mass concentration is that 65% nitric acid mixes stirring; Weighing 6.6g teos solution is again poured in the mixed solution of this step ethyl orthosilicate and powerful the stirring slowly with the speed of per 1 minute 4ml, finally form transparent clear solutions B;
B liquid is poured in the solution A with the speed of 2ml/min, constantly powerful the stirring 0.5 hour, ageing 12 hours finally forms a kind of catalyzer sol solution of ratio.
Get 5 of nickel chromium iron metal beehive carriers, every metallic carrier is that diameter is 5cm, and height is the cylindrical body of 7cm; Metallic carrier carries out the described pretreatment of preamble, then metal beehive carrier is immersed in the above-mentioned catalyst solution, immerses 10 minutes at every turn; Each coating will be used drier, 3 times repeatedly, in air, under room temperature, utilizes sorbing materials such as degreasing cotton, filter paper that it was dried in the shade 3 hours at last; Then in the baking box in air under 80 ℃ of temperature dry 3 hours; With the stove cooling, take out, obtain the surface and scribble SiO
2-Al
2O
3The metal beehive catalytic carrier of catalyzer.Isocyanic acid hydrolyst (SiO
2-Al
2O
3) quality be 3% of metal beehive carrier quality, in the isocyanic acid hydrolyst, the quality percentage composition of each composition is aluminium sesquioxide (Al
2O
3) 50%, silica (SiO
2) 50%.
Through test, add the above-mentioned isocyanic acid hydrolyst SiO that is coated with in the isocyanic acid hydrolyzation catalysis device
2-Al
2O
3Metal beehive carrier after, the conversion ratio of isocyanic acid reaches 94% in the time of 200 ℃, more than 250 ℃ the time, the isocyanic acid conversion ratio all reaches 100%.
The above is merely preferred embodiment of the present invention, and is in order to restriction the present invention, not all within spirit of the present invention and principle, any modification of being done, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. segmented solid urea decomposition ammonia-preparing device is characterized in that: the urea pyrolysis catalytic device (3) and the isocyanic acid hydrolyzation catalysis device (6) that are set in turn in the ammonia gas react jar (2) by ammonia gas react jar (2), by airflow direction are formed; The front end of ammonia gas react jar (2) is provided with urea material feeding mouth (1), and the rear end is provided with ammonia delivery outlet (10), is provided with water vapor delivery conduit (9) on the next door of urea material feeding mouth (1); Inboard at the ammonia gas react jar (2) of urea pyrolysis catalytic device (3) corresponding position is provided with first Electric heating appliance (4) and first temperature transducer (5); Inboard at the ammonia gas react jar (2) of isocyanic acid hydrolyzation catalysis device corresponding position is provided with second Electric heating appliance (7) and second temperature transducer (8); Urea pyrolysis catalytic device (3) is by being coated with glass coating SiO
2-Al
2O
3And the multiple layer metal silk screen carrier of urea supported pyrolysis catalytic agent Pt, Ag or Pd constitutes; Isocyanic acid hydrolyzation catalysis device (6) is by applying isocyanic acid hydrolyst SiO
2And Al
2O
3Metal beehive carrier constitute.
2. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1 is characterized in that: the quality of glass coating and the agent of urea pyrolysis catalytic and for the wire mesh carrier quality 1～5%; In glass coating and the agent of urea pyrolysis catalytic, the quality percentage composition of Pt, Ag or Pd is 0.1～0.5%, 1～5% or 0.1～0.5%, and all the other are SiO
2And Al
2O
3The glass coating of forming, SiO in the glass coating
2The quality percentage composition is 60～80%.
3. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1, it is characterized in that: the quality of isocyanic acid hydrolyst is 1～5% of a metal beehive carrier quality, and the isocyanic acid hydrolyst is by SiO
2And Al
2O
3Form, wherein SiO
2The quality percentage composition be 50%～60%.
4. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1 is characterized in that: first heating equipment (4) and second heating equipment (5) are electromagnetic heating coil, and electromagnetic heating coil adopts enameled cable to process, the individual layer tiling; The number of turn is between 40～60, the diameter 2～6mm of every enameled cable.
5. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1; It is characterized in that: first heating equipment (4) and first temperature transducer (5) are controlled through the instruction call wire by electrical adjustment and control unit ECU, make the interior temperature maintenance of urea pyrolysis catalytic device (3) in the scope of 152～400 ℃ of urea pyrolysis temperatures.
6. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1; It is characterized in that: second heating equipment (7) and second temperature transducer (8) are controlled through the instruction call wire by electrical adjustment and control unit ECU, make the interior temperature maintenance of isocyanic acid hydrolyzation catalysis device (6) in the scope of 300～500 ℃ of isocyanic acid hydrolysis temperatures.
7. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1 is characterized in that: by the amount of the water vapor of (2) in water vapor delivery conduit (9) the feeding ammonia gas react jar and the mol ratio that urea material feeding mouth (1) gets into the urea amount of (2) in the ammonia gas react jar is 1～1.5: 1.
8. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1; It is characterized in that: wire gaze and metal beehive carrier are the Ni-Cr-Fe alloy material of anti-700～900 ℃ of high temperature; Wherein the Ni mass content 35%, Cr mass content 20%, Fe mass content 45%; Wire gaze aperture density is 300 orders, and the metal beehive carrier aperture density is 300 orders.
9. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1, it is characterized in that: wire gaze and metal beehive carrier are fixed by welding in the inside of ammonia gas react jar (2).
10. a kind of segmented solid urea decomposition ammonia-preparing device as claimed in claim 1, it is characterized in that: the urea decomposition ammonia-preparing device is installed in the front of exhaust gas processing device in the motor vehicle exhaust emission pipeline.
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| CN2012101222679A CN102635427A (en) | 2012-04-24 | 2012-04-24 | Sectional type ammonia generating device for discomposing solid urea |
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|---|---|---|---|
| CN2012101222679A CN102635427A (en) | 2012-04-24 | 2012-04-24 | Sectional type ammonia generating device for discomposing solid urea |
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Cited By (19)
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| CN102943703A (en) * | 2012-12-07 | 2013-02-27 | 吉林大学 | Device for quantitatively generating ammonia from solid urea |
| CN103089382A (en) * | 2013-01-30 | 2013-05-08 | 吉林省众鑫汽车装备有限公司 | Urea tank |
| CN103114897A (en) * | 2013-01-30 | 2013-05-22 | 吉林省众鑫汽车装备有限公司 | Motor vehicle tail gas treater |
| CN103950953A (en) * | 2014-05-10 | 2014-07-30 | 南京宇行环保科技有限公司 | Device and method for producing ammonia by use of urea pyrolysis for flue gas denitrification |
| CN104047689A (en) * | 2014-07-15 | 2014-09-17 | 中国重汽集团济南动力有限公司 | Post-processing system with urea hydrolysis function |
| CN107158902A (en) * | 2017-04-21 | 2017-09-15 | 北京国电龙源环保工程有限公司 | SO in coal-fired flue-gas3Front end removing system and its removal methods |
| CN107321184A (en) * | 2017-07-20 | 2017-11-07 | 浙江交通职业技术学院 | Selective catalysis reduction honeycomb substrate and monitoring method with micro-structural thermometric |
| CN107605577A (en) * | 2017-11-03 | 2018-01-19 | 大连大学 | A kind of urea for vehicle hydrolysis SCR system and its control method |
| CN107664054A (en) * | 2016-07-30 | 2018-02-06 | 东北林业大学 | A kind of SCR system based on hydrolysis of urea |
| CN108043422A (en) * | 2017-11-27 | 2018-05-18 | 中国日用化学工业研究院 | A kind of catalyst and preparation method of urea in swimming pool water of degrading |
| CN110073085A (en) * | 2016-12-21 | 2019-07-30 | 珀金斯发动机有限公司 | A kind of improved selective catalytic reduction system operating |
| CN110073086A (en) * | 2016-12-21 | 2019-07-30 | 珀金斯发动机有限公司 | A kind of improved selective catalytic reduction system operating |
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| CN112495452A (en) * | 2020-12-02 | 2021-03-16 | 安徽金禾实业股份有限公司 | Catalyst activation method for fluidized bed reactor |
| CN113006904A (en) * | 2021-02-24 | 2021-06-22 | 合肥工业大学 | Solid urea ammonia supply device for vehicle |
| CN113750948A (en) * | 2021-09-09 | 2021-12-07 | 西安热工研究院有限公司 | Urea catalytic hydrolysis reactor and method for flue gas denitration |
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| CN114433157A (en) * | 2020-10-30 | 2022-05-06 | 陕西青朗万城环保科技有限公司 | Urea microwave hydrolysis catalyst and preparation method thereof |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040040288A1 (en) * | 2002-02-14 | 2004-03-04 | Eberhard Jacob | Method and apparatus for producing ammonia (NH3) |
| DE102006059546A1 (en) * | 2006-12-16 | 2008-06-19 | Pierburg Gmbh | Device for thermal decomposition of dry urea to ammonia and thermolysis product, comprises a thermolysis reactor having a heating unit and air gap isolation, and feeding device having fluid exhausting device and conveying line |
| CN101395350A (en) * | 2006-01-27 | 2009-03-25 | 皮尔伯格有限责任公司 | Device for the reduction of nitrogen oxides in the exhaust gas of internal combustion engines |
| WO2009053135A1 (en) * | 2007-10-18 | 2009-04-30 | Pierburg Gmbh | Exhaust gas aftertreatment system for an internal combustion engine |
| CN102132016A (en) * | 2008-06-25 | 2011-07-20 | 康明斯过滤Ip公司 | Catalytic devices for converting urea to ammonia |
-
2012
- 2012-04-24 CN CN2012101222679A patent/CN102635427A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040040288A1 (en) * | 2002-02-14 | 2004-03-04 | Eberhard Jacob | Method and apparatus for producing ammonia (NH3) |
| CN101395350A (en) * | 2006-01-27 | 2009-03-25 | 皮尔伯格有限责任公司 | Device for the reduction of nitrogen oxides in the exhaust gas of internal combustion engines |
| DE102006059546A1 (en) * | 2006-12-16 | 2008-06-19 | Pierburg Gmbh | Device for thermal decomposition of dry urea to ammonia and thermolysis product, comprises a thermolysis reactor having a heating unit and air gap isolation, and feeding device having fluid exhausting device and conveying line |
| WO2009053135A1 (en) * | 2007-10-18 | 2009-04-30 | Pierburg Gmbh | Exhaust gas aftertreatment system for an internal combustion engine |
| CN102132016A (en) * | 2008-06-25 | 2011-07-20 | 康明斯过滤Ip公司 | Catalytic devices for converting urea to ammonia |
Cited By (24)
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| CN102943703A (en) * | 2012-12-07 | 2013-02-27 | 吉林大学 | Device for quantitatively generating ammonia from solid urea |
| CN103089382A (en) * | 2013-01-30 | 2013-05-08 | 吉林省众鑫汽车装备有限公司 | Urea tank |
| CN103114897A (en) * | 2013-01-30 | 2013-05-22 | 吉林省众鑫汽车装备有限公司 | Motor vehicle tail gas treater |
| CN103950953A (en) * | 2014-05-10 | 2014-07-30 | 南京宇行环保科技有限公司 | Device and method for producing ammonia by use of urea pyrolysis for flue gas denitrification |
| CN103950953B (en) * | 2014-05-10 | 2015-12-09 | 南京宇行环保科技有限公司 | A kind of device and method of denitrating flue gas urea pyrolysis ammonia |
| CN104047689A (en) * | 2014-07-15 | 2014-09-17 | 中国重汽集团济南动力有限公司 | Post-processing system with urea hydrolysis function |
| CN107664054A (en) * | 2016-07-30 | 2018-02-06 | 东北林业大学 | A kind of SCR system based on hydrolysis of urea |
| CN110073085A (en) * | 2016-12-21 | 2019-07-30 | 珀金斯发动机有限公司 | A kind of improved selective catalytic reduction system operating |
| CN110073085B (en) * | 2016-12-21 | 2021-12-31 | 珀金斯发动机有限公司 | Improved selective catalytic reduction system |
| CN110073086B (en) * | 2016-12-21 | 2021-05-28 | 珀金斯发动机有限公司 | Improved selective catalytic reduction system |
| CN110073086A (en) * | 2016-12-21 | 2019-07-30 | 珀金斯发动机有限公司 | A kind of improved selective catalytic reduction system operating |
| CN107158902A (en) * | 2017-04-21 | 2017-09-15 | 北京国电龙源环保工程有限公司 | SO in coal-fired flue-gas3Front end removing system and its removal methods |
| CN107321184A (en) * | 2017-07-20 | 2017-11-07 | 浙江交通职业技术学院 | Selective catalysis reduction honeycomb substrate and monitoring method with micro-structural thermometric |
| CN107605577A (en) * | 2017-11-03 | 2018-01-19 | 大连大学 | A kind of urea for vehicle hydrolysis SCR system and its control method |
| CN108043422A (en) * | 2017-11-27 | 2018-05-18 | 中国日用化学工业研究院 | A kind of catalyst and preparation method of urea in swimming pool water of degrading |
| CN108043422B (en) * | 2017-11-27 | 2021-01-29 | 中国日用化学工业研究院 | Catalyst for degrading urea in swimming pool water and preparation method thereof |
| CN110772986A (en) * | 2019-11-29 | 2020-02-11 | 四川金象赛瑞化工股份有限公司 | Melamine tail gas purification method, melamine tail gas purification device and application thereof |
| CN114060123A (en) * | 2020-08-07 | 2022-02-18 | 长城汽车股份有限公司 | Urea nozzle, automobile and anti-crystallization method |
| CN114433157A (en) * | 2020-10-30 | 2022-05-06 | 陕西青朗万城环保科技有限公司 | Urea microwave hydrolysis catalyst and preparation method thereof |
| CN112495452A (en) * | 2020-12-02 | 2021-03-16 | 安徽金禾实业股份有限公司 | Catalyst activation method for fluidized bed reactor |
| CN114738084A (en) * | 2021-01-07 | 2022-07-12 | 长城汽车股份有限公司 | Automobile aftertreatment system and automobile |
| CN113006904A (en) * | 2021-02-24 | 2021-06-22 | 合肥工业大学 | Solid urea ammonia supply device for vehicle |
| CN113750948A (en) * | 2021-09-09 | 2021-12-07 | 西安热工研究院有限公司 | Urea catalytic hydrolysis reactor and method for flue gas denitration |
| CN113750948B (en) * | 2021-09-09 | 2023-04-28 | 西安热工研究院有限公司 | Urea catalytic hydrolysis reactor and method for flue gas denitration |
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