CN115010148A - Urea catalytic hydrolysis reactor with external ammonia buffer zone - Google Patents
Urea catalytic hydrolysis reactor with external ammonia buffer zone Download PDFInfo
- Publication number
- CN115010148A CN115010148A CN202210654254.XA CN202210654254A CN115010148A CN 115010148 A CN115010148 A CN 115010148A CN 202210654254 A CN202210654254 A CN 202210654254A CN 115010148 A CN115010148 A CN 115010148A
- Authority
- CN
- China
- Prior art keywords
- hydrolysis reactor
- catalyst
- reactor
- ammonia buffer
- mesh
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 142
- 238000006460 hydrolysis reaction Methods 0.000 title claims abstract description 104
- 230000007062 hydrolysis Effects 0.000 title claims abstract description 96
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 66
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 title claims abstract description 52
- 239000004202 carbamide Substances 0.000 title claims abstract description 52
- 230000003197 catalytic effect Effects 0.000 title claims abstract description 34
- 239000003054 catalyst Substances 0.000 claims abstract description 66
- 229910052751 metal Inorganic materials 0.000 claims abstract description 26
- 239000002184 metal Substances 0.000 claims abstract description 26
- 238000010438 heat treatment Methods 0.000 claims abstract description 19
- 239000010410 layer Substances 0.000 claims description 26
- 239000007788 liquid Substances 0.000 claims description 25
- 238000000034 method Methods 0.000 claims description 17
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 15
- 229910052782 aluminium Inorganic materials 0.000 claims description 9
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 9
- 238000005470 impregnation Methods 0.000 claims description 5
- 239000002356 single layer Substances 0.000 claims description 5
- 230000008018 melting Effects 0.000 claims description 3
- 238000002844 melting Methods 0.000 claims description 3
- 239000000725 suspension Substances 0.000 claims description 3
- 238000007654 immersion Methods 0.000 claims 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 abstract description 3
- 239000003546 flue gas Substances 0.000 abstract description 3
- 239000000243 solution Substances 0.000 description 16
- 238000006243 chemical reaction Methods 0.000 description 12
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- 239000007789 gas Substances 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- MNNHAPBLZZVQHP-UHFFFAOYSA-N diammonium hydrogen phosphate Chemical compound [NH4+].[NH4+].OP([O-])([O-])=O MNNHAPBLZZVQHP-UHFFFAOYSA-N 0.000 description 4
- 238000009413 insulation Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 229910000388 diammonium phosphate Inorganic materials 0.000 description 3
- 235000019838 diammonium phosphate Nutrition 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000010865 sewage Substances 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 239000004480 active ingredient Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000012295 chemical reaction liquid Substances 0.000 description 2
- 238000007598 dipping method Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 239000011949 solid catalyst Substances 0.000 description 2
- 239000007790 solid phase Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920000742 Cotton Polymers 0.000 description 1
- 239000005696 Diammonium phosphate Substances 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 238000010793 Steam injection (oil industry) Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- BVCZEBOGSOYJJT-UHFFFAOYSA-N ammonium carbamate Chemical compound [NH4+].NC([O-])=O BVCZEBOGSOYJJT-UHFFFAOYSA-N 0.000 description 1
- LFVGISIMTYGQHF-UHFFFAOYSA-N ammonium dihydrogen phosphate Chemical compound [NH4+].OP(O)([O-])=O LFVGISIMTYGQHF-UHFFFAOYSA-N 0.000 description 1
- 229910000387 ammonium dihydrogen phosphate Inorganic materials 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- KXDHJXZQYSOELW-UHFFFAOYSA-N carbonic acid monoamide Natural products NC(O)=O KXDHJXZQYSOELW-UHFFFAOYSA-N 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000012851 eutrophication Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000011552 falling film Substances 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 239000002638 heterogeneous catalyst Substances 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 description 1
- 235000019837 monoammonium phosphate Nutrition 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 150000003018 phosphorus compounds Chemical class 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/02—Preparation, purification or separation of ammonia
- C01C1/08—Preparation of ammonia from nitrogenous organic substances
- C01C1/086—Preparation of ammonia from nitrogenous organic substances from urea
-
- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Catalysts (AREA)
Abstract
The invention relates to the technical field of flue gas denitration of thermal power plants, in particular to a urea catalytic hydrolysis reactor with an external ammonia buffer zone, which comprises a hydrolysis reactor shell with a square cross section and an ammonia buffer tank arranged outside the hydrolysis reactor shell, wherein an ammonia outlet and a safety valve outlet of the hydrolysis reactor shell are connected with an inlet of the ammonia buffer tank, a heating coil cluster is fixed in the hydrolysis reactor shell, catalyst layers are arranged on the upper side and the lower side of the heating coil cluster, the catalyst layers are metal mesh catalyst layers, and each metal mesh catalyst layer comprises a mesh framework and a catalyst loaded on the mesh framework.
Description
Technical Field
The invention relates to the technical field of flue gas denitration of thermal power plants, in particular to a urea catalytic hydrolysis reactor externally provided with an ammonia buffer zone.
Background
The urea hydrolysis ammonia preparation process is to hydrolyze urea solution in a pressure kettle to generate ammonia gas/carbon dioxide/water. The urea hydrolysis technology is derived from a waste liquid recovery process in urea production in the chemical industry, and when the urea hydrolysis technology is applied to a preparation process of an SCR flue gas denitration reducing agent in a thermal power plant, different process flows, different operation environments and different operation parameters need to be faced, and the process design has obvious differences.
As shown in figure 1, the traditional hydrolysis reactor generally adopts a kettle type structure, the cross section of a kettle body is circular, the liquid level of reaction liquid is positioned in the middle of the kettle body, an ammonia reaction zone is arranged below the liquid level, heating coils are uniformly arranged in the ammonia reaction zone, an ammonia buffer zone is arranged above the liquid level, and an ammonia outlet is positioned on the upper part of the ammonia buffer zone. The existing hydrolysis device has the common problems of large volume of a reactor, slow load response rate, blockage of a blow-off pipe by a hydrolysis intermediate product and the like in the using process. The urea hydrolysis reaction rate is slow, and in order to meet the ammonia demand for SCR, the hydrolysis reaction temperature needs to be increased or the volume of the reactor needs to be increased. Some acidic substances (such as ammonium carbamate and the like) are generated in the urea hydrolysis process, oxide films on the surface of the stainless steel pipeline are seriously corroded, the corrosion degree is increased along with the increase of the temperature, and therefore, the corrosion rate is increased by increasing the reaction temperature. The volume of the reactor is increased, so that the manufacturing cost is increased, and the variable load response time of the hydrolysis reactor is prolonged and the emission of nitrogen oxides exceeds the standard during the variable load period of a unit due to the large thermal inertia of the urea solution in the reactor.
The addition of the catalyst can increase the hydrolysis reaction rate, thereby reducing the reaction temperature, reducing the reactor volume, and can reduce equipment corrosion and increase the variable load response rate. The researchers developed a series of non-metallic materials, metals, metal oxides and metal mixed oxides as urea hydrolysis catalysts, and greatly improved the hydrolysis efficiency and rate. For example, patent CN201310344322.3 discloses a method and apparatus for catalytic hydrolysis of urea, wherein diammonium hydrogen phosphate and ammonium dihydrogen phosphate with different proportions are added as catalysts in a urea hydrolysis reactor, but the liquid catalyst is directly mixed with a reaction solution, has large loss, needs to be supplemented at any time, causes phosphorus compounds in wastewater, and causes eutrophication of water body due to direct discharge. For another example, patent CN202110553273.9 discloses a method for catalyzing urea hydrolysis by using nano alumina, which uses nano alumina as a catalyst to perform urea catalytic hydrolysis reaction in a hydrolysis reactor, and a steam injection system is installed at the lower part of the hydrolysis reactor. Patent 202023134049.6 discloses a system of heterogeneous catalytic hydrolysis system ammonia of SCR denitration urea adopts fixed bed shell and tube reactor, and spherical catalyst granule loads in the shell and tube, and urea solution sprays into in the heterogeneous reactor of hydrolysising through spray set. In the method, the solid heterogeneous catalyst is adopted, and the alumina powder or spherical particles are added into the reaction liquid, so that the problem that the liquid catalyst is easy to lose is solved, but the contact area of the solid phase catalyst is small, and the catalytic efficiency needs to be further improved.
After the addition of the catalyst, the structure of the hydrolysis reactor needs to be redesigned. For example, patent CN201510487560.9 discloses a urea catalytic hydrolysis reactor with double air chambers for heating and a method thereof, which comprises a reaction chamber and a blowdown chamber, wherein the upper layer of the liquid containing sewage is discharged into the blowdown chamber by periodically increasing the liquid level of the reaction chamber, and the blowdown liquid is discharged after being secondarily decomposed in the blowdown chamber. Also, for example, patent No. cn201720817064.x discloses a vertical urea composite catalytic hydrolysis reactor for denitration, wherein a liquid distribution device is installed on the upper portion of the reactor shell, and a falling film distribution device is installed below the liquid distribution device, so that the three functions of using no catalyst, using liquid catalyst, and using solid catalyst can be switched. However, the two structural designs still have the problems of large volume, insufficient contact between the catalyst and the reaction solution and the like, and the vertical reactor structure is not beneficial to the diffusion and escape of ammonia gas.
The catalyst can accelerate the hydrolysis reaction rate, but has small influence on the heat transfer process, so that the urea catalytic hydrolysis reactor needs to balance the size of the heating area of the coil pipe while reducing the volume, and ensures that a sufficient number of heating coil pipes are arranged in the reduced reactor structure. On the other hand, the existing hydrolysis reactors are all provided with ammonia buffer zones, so that although the variable load response capacity is improved, the volume of the reactor is obviously increased, and meanwhile, the flexibility of system operation is reduced due to the direct connection of the ammonia buffer zones and the reaction zones.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a urea catalytic hydrolysis reactor with an external ammonia buffer zone, which has the advantages of compact structure, safety, flexibility, low cost and easy maintenance.
The invention is realized by the following technical scheme: the utility model provides an external ammonia buffer's urea catalytic hydrolysis reactor, includes that the cross section is square hydrolysis reactor casing and arranges the ammonia buffer tank outside hydrolysis reactor casing, and hydrolysis reactor casing passes through the ammonia export and the entry linkage of relief valve and ammonia buffer tank, hydrolysis reactor casing internal fixation has a heating coil cluster, and the upper and lower both sides of heating coil cluster all are provided with a catalyst layer, the catalyst layer is the netted catalyst layer of metal, the netted catalyst layer of metal includes netted skeleton and the catalyst of load on netted skeleton.
Further, the ammonia buffer tank is of a vertical structure and is provided with a heat insulation layer.
Further, the working pressure of the shell of the hydrolysis reactor is 0.4-0.6Mpa, and the working pressure of the ammonia buffer tank is 0.3-0.4 Mpa.
Furthermore, the net-shaped framework is a single-layer net-shaped structure woven by metal aluminum wires, and the porosity of the net-shaped framework is smaller than 2 mm.
Furthermore, the nodes of the single-layer mesh structure are overlapped by adopting hot melting.
Further, the catalyst is alumina, and the loading amount of the catalyst is 5-10% of the molar ratio.
Further, the catalyst is loaded on the net-shaped framework through an impregnation method, specifically, the net-shaped framework is impregnated in a catalyst suspension and heated, and after the impregnation is completed, the net-shaped framework is dried to obtain the metal net-shaped catalyst layer.
Further, a demister is also arranged in the ammonia gas outlet of the shell of the hydrolysis reactor; still be provided with the level gauge outside the hydrolysis reactor casing, the level gauge is used for measuring the liquid level of hydrolysis reactor casing inside urea solution, and the hydrolysis reactor casing passes through the entry intercommunication of relief valve with the ammonia buffer tank.
Furthermore, a plug is arranged on one side of the hydrolysis reactor shell, and the heating coil cluster is fixed in the hydrolysis reactor shell through the plug.
Furthermore, the cross section of the plug is square.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a urea catalytic hydrolysis reactor with an external ammonia buffer zone, wherein two catalyst layers are arranged in a shell of the hydrolysis reactor, and the catalyst layers are metal mesh catalyst layers, so that the specific surface area of the metal mesh catalyst layers is large, the contact area of a catalyst and a reaction solution can be obviously increased, and the catalytic efficiency is improved. On the other hand, the metal mesh catalyst is easier to fix and replace than the powdery and spherical catalysts, so that the problem that the solid catalyst is difficult to supplement is solved, and compared with the liquid catalyst ammonium hydrogen phosphate or diammonium hydrogen phosphate, the metal mesh catalyst does not generate a phosphorus-containing compound and has no influence on the pollution discharge process of a reactor;
according to the urea catalytic hydrolysis reactor with the external ammonia buffer zone, the cross section of the shell of the hydrolysis reactor is adjusted from a traditional circle to a square shape, and when the diameter of the circular section is equal to the length of the side of the square section, the area of the square section is obviously larger than that of the circular section, so that on the premise that the floor area of the hydrolysis reactor is not changed, the volume of a space for arranging the heating coil clusters can be increased by adopting the square section, and therefore, enough heating coil clusters are arranged in a reduced reactor structure.
According to the urea catalytic hydrolysis reactor with the external ammonia buffer zone, the ammonia buffer zone is not arranged in the shell of the hydrolysis reactor, the hydrolysis reactor is completely filled with urea solution, the volume of the hydrolysis reactor can be reduced by more than 50%, an ammonia buffer tank is additionally arranged outside the hydrolysis reactor for ensuring the stability of ammonia gas conveying pressure in the variable load process, the inlet of the ammonia buffer tank is connected with the ammonia gas outlet and the safety valve outlet of the shell of the hydrolysis reactor, and the ammonia buffer tank can be simultaneously used with a plurality of hydrolyzers. After the ammonia buffer zone is moved to the outside from the inside of the hydrolysis reactor, the ammonia reaction zone is separated from the ammonia buffer zone, the operation flexibility of the hydrolysis reactor is obviously improved, when the SCR system needs emergency shutdown, the hydrolysis reactor can be quickly cut off, redundant ammonia gas is sent into an ammonia buffer tank for storage, the evacuation treatment as the traditional hydrolysis reactor is not needed, a large amount of ammonia gas is saved, and the influence on the environment is reduced;
furthermore, the urea catalytic hydrolysis reactor with the external ammonia buffer zone has the working pressure of 0.4-0.6Mpa, the adopted ammonia buffer tank is positioned outside the reactor, the working pressure of 0.3-0.4Mpa is lower than the pressure in the reactor, the urea catalytic hydrolysis reactor can prevent the flash evaporation boiling of urea solution by adopting high pressure, and the ammonia buffer tank can prevent the product gas from condensing and crystallizing by reverse reaction by adopting low pressure.
Furthermore, the urea catalytic hydrolysis reactor with the external ammonia buffer zone provided by the invention adopts metal aluminum to manufacture the net-shaped framework of the metal net-shaped catalyst layer, adopts an impregnation method to load the alumina powder on the metal aluminum framework as an active ingredient, has large specific surface area of the net-shaped framework, is easy to stably load the active ingredient, has good inertia of the metal aluminum and the alumina powder in an acid solution, has low corrosion rate and basically has no catalyst loss.
Furthermore, the urea catalytic hydrolysis reactor with the external ammonia buffer zone provided by the invention adopts alumina as the active component of the catalyst, has high catalytic activity at low temperature, can remarkably accelerate the hydrolysis reaction rate, reduces the volume of the reactor by more than 30%, improves the variable load response capability, and prevents the emission of nitrogen oxides of a boiler SCR system from exceeding the standard.
Furthermore, the urea catalytic hydrolysis reactor with the external ammonia buffer area has the advantages that the porosity of the adopted metal mesh catalyst is small, and the metal mesh catalyst can remove foams in the product gas like a demister, so that the water content of the product gas is reduced, and the product gas is prevented from reversely reacting and crystallizing.
Furthermore, the system of the invention adopts a safety valve arranged on the reactor shell to ensure the safety and reliability of the urea catalytic hydrolysis reaction; and meanwhile, a liquid level meter is also arranged, so that the liquid level of the urea solution in the shell can be measured in time.
Drawings
FIG. 1 is a schematic diagram of a hydrolysis reactor for comparison.
FIG. 2 is a schematic diagram of the structure of a hydrolysis reactor according to an embodiment of the present invention.
Fig. 3 is a cross-sectional view a-a of fig. 2.
Fig. 4 is a schematic structural diagram of a mesh-shaped catalyst layer according to an embodiment of the present invention.
FIG. 5 is a graph comparing the performance of the catalysts described in the examples of the present invention.
FIG. 6 is a graph of the loading of the catalyst as a function of hydrolysis efficiency in an example of the invention.
In the figure: 1. the device comprises a saturated steam inlet, 2 a drainage outlet, 3 a plug, 4 a hydrolysis reactor shell, 5 a reactor liquid level, 6 a catalyst layer, 7 a heating coil cluster, 8 a urea solution inlet, 9 a sewage outlet, 10 a liquid level meter, 11 a demister, 12 an ammonia outlet, 13 a safety valve, 14 an ammonia buffer tank and 15 a conveying pipeline.
Detailed Description
The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.
As shown in fig. 2 and 3, the invention provides a urea catalytic hydrolysis reactor with an external ammonia buffer zone, which comprises a hydrolysis reactor shell 4 with a square cross section, wherein the bottom of the hydrolysis reactor shell 4 is provided with a urea solution inlet 8 and a sewage outlet 9, and the top of the hydrolysis reactor shell 4 is provided with an ammonia gas outlet 12 and a safety valve 13, wherein a heating coil cluster 7 is fixedly arranged in the hydrolysis reactor shell 4 through a plug 3, the upper side and the lower side of the heating coil cluster 7 are respectively provided with a catalyst layer 6, and the catalyst layer 6 is a metal mesh catalyst layer; the hydrolysis reactor shell 4 is not provided with an ammonia buffer zone, the urea solution is completely filled in the hydrolysis reactor, the urea solution liquid level in the hydrolysis reactor shell 4 is flush with the upper part of the shell, the ammonia buffer tank 14 is additionally arranged outside the hydrolysis reactor shell 4 for ensuring the stability of the ammonia conveying pressure in the variable load process, the ammonia outlet 12 of the hydrolysis reactor shell 4 is communicated with the inlet of the ammonia buffer tank 14, and the outlet of the ammonia buffer tank 14 is communicated with the conveying pipeline 15.
Preferably, as shown in fig. 4, the metal mesh catalyst layer includes a mesh-like skeleton made of metal aluminum and a catalyst supported on the mesh-like skeleton, and the catalyst is alumina, and alumina powder is supported on the mesh-like skeleton by an impregnation method to obtain a solid-phase catalyst having a metal mesh structure as an active component.
Preferably, the net-shaped framework is a single-layer net-shaped structure woven by 0.4mm of metal aluminum wires, the porosity of the net-shaped framework is less than 2mm, and nodes are lapped by hot melting;
preferably, when the catalyst alumina powder is loaded, the mesh-shaped aluminum wire framework is ultrasonically cleaned and then is placed into a suspension liquid made of nano alumina particles for dipping, microwave heating is adopted in the process, the mesh-shaped aluminum wire framework is placed into a heating furnace for drying for 3-5 hours after dipping is completed, water is evaporated, and the alumina particles are solidified.
Preferably, as shown in fig. 5, alumina is used as the catalyst, which has good catalytic properties at low temperature, and the catalytic efficiency is superior to that of the liquid catalysts such as diammonium phosphate, which are commonly used in industry at present.
Preferably, as shown in FIG. 6, when the loading amount of alumina is 5 to 10% by mole, the corresponding urea hydrolysis efficiency is highest.
Preferably, the ammonia buffer tank 14 is of a vertical structure, a heat insulation layer is arranged on the ammonia buffer tank, the heat insulation layer comprises a steam interlayer and heat insulation cotton, the working temperature is not lower than 120 ℃, and the working pressure is stabilized at 0.3-0.4 Mpa.
Preferably, a saturated steam inlet 1 and a hydrophobic outlet 2 are respectively arranged on the outer side of the plug 3;
preferably, the cross section of the plug 3 is square.
Preferably, a safety valve 13 is used for ensuring the safety and reliability of the urea catalytic hydrolysis reaction, and the hydrolysis reactor shell 4 is communicated with the inlet of the ammonia buffer tank 14 through the safety valve 13.
Preferably, a level gauge 10 is provided on the hydrolysis reactor housing 4 for detecting the reactor level 5.
Preferably, a demister 11 is further disposed in the ammonia gas outlet 12 of the hydrolysis reactor shell 4 for removing mist-like liquid droplets from the product gas.
The working pressure of the urea catalytic hydrolysis reactor with the external ammonia buffer zone is 0.4-0.6Mpa, the working temperature is 135-150 ℃, and the feeding mass concentration of the urea solution is 40-60%.
Claims (10)
1. The utility model provides an external ammonia buffer zone's urea catalytic hydrolysis reactor, characterized in that, including the cross section for square hydrolysis reactor casing (4) and arrange at the outside ammonia buffer tank (14) of hydrolysis reactor casing (4), hydrolysis reactor casing (4) are connected with the entry of ammonia buffer tank (14) through ammonia export (12) and relief valve (13), hydrolysis reactor casing (4) internal fixation has heating coil cluster (7), and the upper and lower both sides of heating coil cluster (7) all are provided with a catalyst layer (6), catalyst layer (6) are metal mesh catalyst layer, metal mesh catalyst includes layer mesh skeleton and the catalyst of load on mesh skeleton.
2. The reactor of claim 1, wherein the ammonia buffer tank (14) is of a vertical structure, and the ammonia buffer tank (14) has a heat insulating layer.
3. The urea catalytic hydrolysis reactor with an external ammonia buffer zone as claimed in claim 1, wherein the operating pressure of the hydrolysis reactor shell (4) is 0.4Mpa-0.6Mpa, and the operating pressure of the ammonia buffer tank (14) is 0.3Mpa-0.4 Mpa.
4. The reactor of claim 1, wherein the mesh framework is a single-layer mesh structure woven by aluminum wires, and the porosity of the mesh framework is less than 2 mm.
5. The reactor of claim 4, wherein the nodes of the single-layer mesh structure are overlapped by hot melting.
6. The reactor of claim 1, wherein the catalyst is alumina and the loading of the catalyst is 5 to 10 mole percent.
7. The reactor of claim 1, wherein the catalyst is supported on the mesh-like framework by an impregnation method, and specifically, the mesh-like framework is immersed in a suspension of the catalyst and heated, and then dried after the immersion is completed, so as to obtain the metal mesh-like catalyst layer.
8. The urea catalytic hydrolysis reactor with external ammonia buffer zone as set forth in claim 1, characterized in that a demister (11) is further disposed in the ammonia gas outlet (12) of the hydrolysis reactor shell (4); the hydrolysis reactor shell (4) is also provided with a liquid level meter (10), and the liquid level meter (10) is used for measuring the liquid level of the urea solution in the hydrolysis reactor shell (4).
9. The urea catalytic hydrolysis reactor with the external ammonia buffer zone as claimed in claim 1, wherein a plug (3) is disposed at one side of the hydrolysis reactor housing (4), and the heating coil bundle (7) is fixed in the hydrolysis reactor housing (4) through the plug (3).
10. The reactor for urea catalytic hydrolysis with external ammonia buffer according to claim 9, characterized in that the cross section of the bulkhead (3) is square.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210654254.XA CN115010148A (en) | 2022-06-10 | 2022-06-10 | Urea catalytic hydrolysis reactor with external ammonia buffer zone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210654254.XA CN115010148A (en) | 2022-06-10 | 2022-06-10 | Urea catalytic hydrolysis reactor with external ammonia buffer zone |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115010148A true CN115010148A (en) | 2022-09-06 |
Family
ID=83073160
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210654254.XA Pending CN115010148A (en) | 2022-06-10 | 2022-06-10 | Urea catalytic hydrolysis reactor with external ammonia buffer zone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115010148A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118681512A (en) * | 2024-08-23 | 2024-09-24 | 成都锐思环保技术股份有限公司 | Partition temperature-control urea hydrolysis reactor and control method thereof |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006223937A (en) * | 2005-02-15 | 2006-08-31 | Babcock Hitachi Kk | Decomposing catalyst for urea, and exhaust gas denitrification method and apparatus using the catalyst |
| CN203922753U (en) * | 2014-06-06 | 2014-11-05 | 四川晨光工程设计院 | A kind of urea hydrolyser for the production of ammonia |
| JP2018020271A (en) * | 2016-08-02 | 2018-02-08 | 株式会社タクマ | Operation method of urea hydrolyzing apparatus |
| CN108358344A (en) * | 2018-03-13 | 2018-08-03 | 常州大学 | Promote deamination catalyst treatment and produces urea waste water device |
| CN210683234U (en) * | 2019-07-16 | 2020-06-05 | 浙江蓝天求是环保股份有限公司 | Urea hydrolysis ammonia production system utilizing waste heat for graded heating |
| CN111482143A (en) * | 2020-05-08 | 2020-08-04 | 济南山源环保科技有限公司 | Urea catalytic hydrolysis generator capable of recycling catalyst and catalytic hydrolysis method |
| CN113511659A (en) * | 2021-08-24 | 2021-10-19 | 西安热工研究院有限公司 | Urea hydrolysis ammonia production device and method for denitration of flue gas of thermal power plant |
| 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 |
| CN114345386A (en) * | 2021-12-30 | 2022-04-15 | 北京核力同创科技有限公司 | Catalyst loading device for degrading high molecular organic compound by electron beam irradiation |
-
2022
- 2022-06-10 CN CN202210654254.XA patent/CN115010148A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006223937A (en) * | 2005-02-15 | 2006-08-31 | Babcock Hitachi Kk | Decomposing catalyst for urea, and exhaust gas denitrification method and apparatus using the catalyst |
| CN203922753U (en) * | 2014-06-06 | 2014-11-05 | 四川晨光工程设计院 | A kind of urea hydrolyser for the production of ammonia |
| JP2018020271A (en) * | 2016-08-02 | 2018-02-08 | 株式会社タクマ | Operation method of urea hydrolyzing apparatus |
| CN108358344A (en) * | 2018-03-13 | 2018-08-03 | 常州大学 | Promote deamination catalyst treatment and produces urea waste water device |
| CN210683234U (en) * | 2019-07-16 | 2020-06-05 | 浙江蓝天求是环保股份有限公司 | Urea hydrolysis ammonia production system utilizing waste heat for graded heating |
| CN111482143A (en) * | 2020-05-08 | 2020-08-04 | 济南山源环保科技有限公司 | Urea catalytic hydrolysis generator capable of recycling catalyst and catalytic hydrolysis method |
| CN113511659A (en) * | 2021-08-24 | 2021-10-19 | 西安热工研究院有限公司 | Urea hydrolysis ammonia production device and method for denitration of flue gas of thermal power plant |
| 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 |
| CN114345386A (en) * | 2021-12-30 | 2022-04-15 | 北京核力同创科技有限公司 | Catalyst loading device for degrading high molecular organic compound by electron beam irradiation |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118681512A (en) * | 2024-08-23 | 2024-09-24 | 成都锐思环保技术股份有限公司 | Partition temperature-control urea hydrolysis reactor and control method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113750948B (en) | Urea catalytic hydrolysis reactor and method for flue gas denitration | |
| CN201978740U (en) | Urea solution hydrolytic ammonia preparing kettle type reactor | |
| CN115010148A (en) | Urea catalytic hydrolysis reactor with external ammonia buffer zone | |
| CN102267868B (en) | Industrial production apparatus for trichloroethylene | |
| CN208071333U (en) | A kind of low-energy consumption urea hydrolysis reactor | |
| CN102872769B (en) | Gas distributor and slurry bed reactor and crude carbinol synthetic system both comprising same | |
| CN206980684U (en) | A kind of combined type fixed bed reactors | |
| CN112678847A (en) | Urea coupling hydrolyzer and urea coupling hydrolysis method thereof | |
| CN112661172A (en) | System and method for preparing ammonia through SCR (selective catalytic reduction) denitration urea heterogeneous catalytic hydrolysis | |
| CN215288029U (en) | System for preparing ammonia by SCR denitration urea heterogeneous catalysis hydrolysis | |
| CN221847104U (en) | Vertical solid catalyst hydrolysis urea reactor | |
| CN110422860A (en) | A kind of hydrolysis of urea ammonia reaction unit | |
| CN205182685U (en) | Take plate heat exchanger to get half hot isothermal reactor | |
| CN117654377A (en) | Vertical solid catalyst hydrolysis urea reactor | |
| CN105840277B (en) | It is alcohol steam reformed into hydrogen H2SCR system | |
| CN212417487U (en) | Comprehensive absorption tower for preparing hydrogen chloride from graphite | |
| CN210845845U (en) | Environment-friendly spray purification tower for rapidly treating waste gas | |
| CN203922753U (en) | A kind of urea hydrolyser for the production of ammonia | |
| CN216614872U (en) | Hydrolysis hydrogen production device | |
| CN201862397U (en) | Reaction device for absorbing off-gas ozone | |
| CN221905781U (en) | Novel ammonia water evaporation device for coke oven flue gas SCR denitration system | |
| CN216093603U (en) | Novel urea hydrolysis ammonia production reactor | |
| CN201807297U (en) | Equipment for selective catalytic reduction denitrification of flue gas | |
| CN213983603U (en) | Heat accumulating type NOX catalytic reduction device | |
| CN218755030U (en) | Nitric acid device coproduction thermoelectric production system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20220906 |