A kind of reactors for synthesis of ammonia and techniqueTechnical field
The present invention relates to chemical production technology and equipment technical fields, and in particular to a kind of reactors for synthesis of ammonia and technique,In particular to a kind of overall diameter to ruthenium catalysis isothermal hot wall tower reactor and technique.
Background technique
Ammonia is mostly important one of basic chemical industry product, is occupied an important position in national economy.Ammonia is mainly used for agricultureIndustry, synthesis ammonia are the bases of nitrogen fertilizer industry, and ammonia itself is important nitrogen manure, other nitrogen manures are also to utilize synthesis mostlyAmmonia is processed into urea or various ammonium salt fertilizer；Ammonia is also important inorganic chemistry and Organic Chemical Industry basic material simultaneously, usesIn the raw material for producing ammonium, amine, fuel, explosive, pharmacy, synthetic fibers, synthetic resin.
Currently, the fixed bed reactors type for Ammonia Production is more.Fixed bed reactors are also known as packed bed reactionDevice is filled with a kind of reactor of solid catalyst or solid reactant to realize heterogeneous reaction process.Solid catalyst is logicalIt is often in granular form, is piled into the bed of certain altitude (or thickness), bed is stationary, and fluid is reacted by bed.GuWhen fixed bed reactor is for realizing synthesis this kind of gas-solid catalysis of ammonia, solid catalyst is loaded in bed, such as iron-based catalysisAgent and ruthenium-based catalyst.
Synthesizing ammonia is directly synthesized under high temperature, high pressure and catalyst by nitrogen and hydrogen, and the reaction equation of ammonia is synthesized are as follows:3H2+N2→2NH3+ Q, the reaction are exothermic reaction.On the one hand, synthetic ammonia catalyst needs certain catalytic temperature, is reactingCheng Zhong needs reaction gas nitrogen and hydrogen being heated to corresponding temperature；On the other hand, with the progress of reaction, temperature is constantly risenHeight, the too high activity decay that can cause catalyst of temperature.Therefore, the reaction for synthesizing ammonia both needs to heat reaction gas,It needs constantly to remove heat again, keep the temperature in suitable range.
For this purpose, Chinese patent literature CN105883852A discloses a kind of ammonia synthesis reaction system and ammonia synthesis reaction sideMethod, ammonia synthesis reaction system include ammonia convertor, combined type give up pot, feed-water heater, circulation gas-heat exchanger, water cooler,Ammonia United Chiller With, two ammonia coolers, ammonia separator, liquefied ammonia slot, circulator and the heating furnace that goes into operation, which, which passes through to utilize, opensWork heats stove heating gas to be reacted, and is recycled using the combined type pot that gives up to the heat generated after reaction.The technical sideCase has used independent component to carry out temperature adjusting to the gas of reaction front and back, and in reaction process at the catalyst of each bedIn adiabatic process, making in bed that there are larger temperature gradients for catalyst, the reaction temperature temperature difference is larger, and catalytic efficiency is undesirable, andPartial catalyst can be in hot environment, adversely affect to the service life of catalyst.
To reacting most important, above-mentioned technology is added by using independent go into operation for temperature control during ammonia synthesis reactionHot stove and combined type give up pot to realize that temperature regulates and controls, and the device is complicated, and cannot adjust the temperature of catalyst in time, and ruthenium base amminoUse graphitization active carbon for carrier at catalyst, overtemperature easily causes carrier methanation, reduces the service life of catalyst, can also makeThe efficiency of catalyst declines.
Summary of the invention
Therefore, the technical problem to be solved in the present invention is that existing reactors for synthesis of ammonia there are reaction temperature it is not easy to control andThe defect that the device is complicated, to provide a kind of iron ruthenium consecutive relay isothermal reactors for synthesis of ammonia.
The invention solves another technical problem be to overcome existing reactors for synthesis of ammonia that there are reaction temperatures to be not easyControl and the defect that the device is complicated, to provide a kind of synthesis ammonia work using iron ruthenium consecutive relay isothermal reactors for synthesis of ammoniaSkill.
For this purpose, the present invention provides a kind of reactors for synthesis of ammonia, including shell, further include,
Several heat exchanger tubes passed through for unstripped gas are arranged in the inner, the heat exchanger tube along the axially spaced-apart of the shellOne end the first raw material gas inlet for communicating therewith, the unstripped gas outlet that opposite end setting communicates therewith are set；
Catalyst bed is filled between the inner walls and heat exchanger tube and/or between adjacent heat exchange tubes, the raw materialGas outlet is connected to the inner cavity of the catalyst bed, so that the unstripped gas after heat exchanger tube preheating is flowing through the catalysisAmmonia synthesis reaction occurs when agent bed.
Further, the reactors for synthesis of ammonia further includes,
Gas collecting tube protrudes into the enclosure interior along the short transverse of the catalyst bed, along the axial direction of the gas collecting tubeSeveral air inlets are opened up on its tube wall, so that gained reaction gas passes through the air inlet after the catalyst bed reactionIt is collected in into the gas collecting tube.
Further, the gas collecting tube is arranged in the shell along the center line of the shell, and the gas collecting tube oneEnd extends to the external world from the enclosure interior, and to form reaction gas outlet end, the heat exchanger tube arrangement is in the gas collecting tube and shellBetween internal wall.
Further, the percent opening on the gas collection tube wall is 20~40%, the aperture of the air inlet is 4~20mm, it is further preferred that the percent opening is 25~40%, the aperture of the air inlet is 5~15mm,.
Further, the reactors for synthesis of ammonia further includes,
Second raw material gas inlet is set to the shell with the ipsilateral and close housing sidewall in unstripped gas outletOn, second raw material gas inlet and the unstripped gas outlet, so that the unstripped gas in heat exchanger tube enters catalyst bedAnd it reacts.
Further, the reactors for synthesis of ammonia further includes,
Gas distribution unit, has taper or a hemispherical body, the big opening end of the taper or hemispherical body with it is describedFirst raw material gas inlet is arranged in the connection of heat exchanger tube one end, opposite end；
Gas collection unit, has taper or a hemispherical shell, the big opening end of the taper or hemispherical shell with it is describedThe other end of heat exchanger tube is connected to, and the unstripped gas outlet is arranged in opposite end, to collect the unstripped gas in heat exchanger tube.
Further, the ratio of height to diameter of the shell is 8~20:1.
Further, the shell is single layer, is not provided with inner casing.
Further, the ratio between height of the thickness of the catalyst bed and the shell is 1:8~20.
Further, the catalyst bed includes both several catalyst layer, the setting segmentation of adjacent catalyst interlayerPorcelain layers of balls.
Further, the catalyst bed is made of upper catalyst layer and lower catalyst layer, and the upper catalyst layer is filled outFill iron based ammonia synthesis catalyst, the lower catalyst layer loads ruthenium-based ammonia synthetic catalyst, the iron based ammonia synthesis catalyst andThe ratio between admission space of the ruthenium-based ammonia synthetic catalyst is 1:1~4.
Furthermore the present invention also provides the ammonia synthesis process of above-mentioned reactors for synthesis of ammonia, include the following steps:
Unstripped gas is passed through into first raw material gas inlet, the unstripped gas enters in the heat exchanger tube and urges with describedAgent bed indirect heat exchange；
Unstripped gas after preheating exports out from the unstripped gas, into the shell in and urge radially by describedIn the catalyst bed ammonia synthesis reaction occurs for agent bed.
Further, the unstripped gas is hydrogen and nitrogen, and the mass ratio of hydrogen and nitrogen is 2~4.5:1.
Further, air speed of the unstripped gas in the heat exchanger tube is 8000~15000h-1, pressure be 9~12MPa, it is further preferred that air speed of the unstripped gas in the heat exchanger tube is 10000h-1, pressure 10MPa.
Further, the temperature of the catalyst bed is 400~520 DEG C, and pressure is 9~12MPa, further excellentChoosing, the temperature of the catalyst bed are 410~480 DEG C, and pressure is 9~10MPa.
Further, the pressure in the heat exchanger tube is identical as the gas pressure in the catalyst bed.
Technical solution of the present invention has the advantages that
1, reactors for synthesis of ammonia provided by the invention, can carry out efficient heat transmitting, and preheating material gas has energy-savingThe advantages of.Heat exchanger tube passes through catalyst bed, and catalyst reaction heat is realized by exchanging with the raw gas heat flowed in heat exchanger tubeHeat transfer, enters back into catalyst bed after unstripped gas is preheated and is reacted.Unstripped gas temperature when entering catalyst bedDegree, conducive to the progress of ammonia synthesis reaction, has the advantages that energy-saving up to 360 DEG C.
2, reactors for synthesis of ammonia provided by the invention can make catalyst be in suitable temperature, guarantee to urge by heat exchangeThe high activity of agent and the long-time stability of operation.Ammonia synthesis reaction is exothermic reaction, and with thermal accumlation, the too high meeting of temperatureMake catalyst inactivation, the heat exchanger tube in reactor of the invention pass through catalyst bed, cold flow of feed gas through when heat exchanger tube withHeat exchange occurs for catalyst reaction heat, so that the temperature of catalyst is maintained at 405~450 DEG C, avoids catalyst and send out because of high temperatureRaw inactivation.Using traditional ammonia synthesis reactor, because temperature control is not in time or insensitive, catalyst was begun to using 1~2 yearDecline, and reactors for synthesis of ammonia provided by the invention is used, catalyst was just fallen into a decline using 3~5 years
3, the reaction process of reactors for synthesis of ammonia provided by the invention, urging in gas pressure and housing cavity in heat exchanger tubeThe reaction pressure of agent reaction bed is identical or difference is smaller, higher relative to the common liquid phase cooling medium safety such as water.
4, the reaction process of reactors for synthesis of ammonia provided by the invention, can be improved catalyst transformation efficiency, and conversion ratio is15%~20%, it is significantly increased compared with Conventional catalytic efficiency, to reduce discharge, reduces environmental pollution, increase economic efficiency.ThisThe reactor and its technique of invention are easy to amplify, and can be used for 3~180,000 tons/year of ammonia production scales.
Detailed description of the invention
It, below will be to specific in order to illustrate more clearly of the specific embodiment of the invention or technical solution in the prior artEmbodiment or attached drawing needed to be used in the description of the prior art be briefly described, it should be apparent that, it is described belowAttached drawing is some embodiments of the present invention, for those of ordinary skill in the art, before not making the creative laborIt puts, is also possible to obtain other drawings based on these drawings.
Fig. 1 is the structural schematic diagram of reactors for synthesis of ammonia；
Appended drawing reference:
1- shell；2- gas distribution unit；The first raw material gas inlet of 21-；3- heat exchanger tube；4- gas collection unit；41- is formerExpect gas outlet；5- catalyst bed；The second raw material gas inlet of 51-；6- gas collecting tube；61- air inlet；62- reaction gas outlet end.
Specific embodiment
There is provided following embodiments is to preferably further understand the present invention, it is not limited to the best embodiment partyFormula is not construed as limiting the contents of the present invention and protection scope, anyone under the inspiration of the present invention or by the present invention and itsThe feature of his prior art is combined and any and identical or similar product of the present invention for obtaining, all falls within of the inventionWithin protection scope.
Embodiment 1
With reference to Fig. 1, a kind of reactors for synthesis of ammonia, including shell 1 are present embodiments provided, ratio of height to diameter is 8~20:1；IfThere are several heat exchanger tubes 3, is arranged in the inner along the axially spaced-apart of shell 1, to by unstripped gas, one end of heat exchanger tube 3 is through gasDistribution unit 2 is communicated with the first raw material gas inlet 21, and opposite end is communicated through gas collection unit 4 with unstripped gas outlet 41；CatalysisAgent bed 5 is filled between the inner wall of shell 1 and heat exchanger tube 3 and/or between adjacent heat exchange tubes 3, unstripped gas outlet 41 and catalysisThe inner cavity of agent bed 5 is connected to, so that synthesis ammonia occurs when flowing through catalyst bed 5 is anti-for the unstripped gas after the preheating of heat exchanger tube 3It answers.
Nitrogen and hydrogen are passed through gas distribution unit 2 by the first raw material gas inlet 21, subsequently enter each heat exchanger tube 3, exchange heatPipe 3 passes through catalyst bed 5, and heat exchange, nitrogen and hydrogen occur for the nitrogen and hydrogen flowed in catalyst reaction heat and heat exchanger tube 3Enter catalyst bed 5 after gas is preheated, carries out catalysis reaction.Unstripped gas is heated before the reaction, is conducive to ammonia synthesisThe progress of reaction, has the advantages that energy-saving；
Further, as shown in Figure 1, gas distribution unit 2, has taper or hemispherical body, taper or hemispherical sheetThe big opening end of body is connected to 3 one end of heat exchanger tube, and the first raw material gas inlet 21 is arranged in opposite end, is distributed in time convenient for unstripped gas in this wayInto each heat exchanger tube 3；
Gas collection unit 4 has taper or hemispherical shell, the big opening end and heat exchanger tube 3 of taper or hemispherical shellThe other end connection, opposite end be arranged unstripped gas export 41；Specifically, gas collection unit 4 can be sheathed on the enclosure interior,And osculum end forms unstripped gas outlet 41 from 1 internal stretch of shell to the external world, in this way can collect in time the unstripped gas after preheatingAnd it is introduced into catalyst bed 5.
Embodiment 2
In order to improve heat exchanger effectiveness and catalysis reaction efficiency, on the basis of above-described embodiment 1, raw material in the present embodimentGas outlet 41 is connected to through the second raw material gas inlet 51 with the inner cavity of catalyst bed 5, and the second raw material gas inlet 51 is set to shellOn body 1, the side wall ipsilateral and close to shell 1 with unstripped gas outlet 41；Reactor is additionally provided with gas collecting tube 6, along the center of shell 1Line is arranged in shell 1, opens up several air inlets 61 on its tube wall along the axial direction of gas collecting tube 3, and the aperture of air inlet 61 is 4~20mm, percent opening are 20~40%, so that gained reaction gas passes through air inlet 61 into gas collection after the reaction of catalyst bed 5It is collected in pipe 6, and gas collecting tube one end is from 1 internal stretch of shell to the external world, to form reaction gas outlet end 62；
Heat exchanger tube 3 is arranged between 1 inner wall of gas collecting tube 6 and shell.
Using the improved embodiment, pass through the unstripped gas after heat exchanger tube 3 preheats when flowing through catalyst bed 5It axially diffuses and enters catalyst layer generation ammonia synthesis reaction, high catalytic efficiency.When heat exchanger tube 3 passes through catalyst bed 5, cold originalExpect that with catalyst reaction heat efficient heat exchange is occurred for air-flow when heat exchanger tube 3, the temperature of catalyst made to be maintained at 405~450 DEG C,It avoids catalyst to inactivate because of high temperature, extends the service life of catalyst.
Embodiment 3
Guarantee catalyst bed will not overtemperature in the case where, in order to further increase catalytic efficiency, in embodiment 1 or 2On the basis of, catalyst bed 5 includes several catalyst layer in the present embodiment, both adjacent catalyst interlayer setting segmentationsPorcelain layers of balls；Specifically, along the short transverse of shell 1, from top to bottom, catalyst bed 5 be one layer of iron based ammonia synthesis catalyst andOne layer of ruthenium-based ammonia synthetic catalyst layer perhaps one layer of iron based ammonia synthesis catalyst and two layers of ruthenium-based ammonia synthetic catalyst layer orOne layer of iron based ammonia synthesis catalyst and three layers of ruthenium-based ammonia synthetic catalyst layer or two layers of iron based ammonia synthesis catalyst and two layers of rutheniumBase ammonia synthetic catalyst layer, the ratio between the thickness of catalyst bed 5 and the height of shell 1 are 1:8-20；More specifically, catalyst bedLayer 5 is made of upper catalyst layer and lower catalyst layer, and upper catalyst layer loads iron based ammonia synthesis catalyst, and lower catalyst layer loadsThe ratio between admission space of ruthenium-based ammonia synthetic catalyst, iron based ammonia synthesis catalyst and ruthenium-based ammonia synthetic catalyst is 1:1-4, catalysisAgent bed 5 can cover the air inlet 61 on 3 tube wall of gas collecting tube, be avoided that in this way gas without catalyst bed 5 and directly intoEnter in gas collecting tube 3, improves the transformation efficiency of catalyst.
Embodiment 4
The reaction process of the reactors for synthesis of ammonia of the offer of embodiment 3 is be provided.To the first raw material gas inlet 21It is passed through the gaseous mixture of hydrogen and nitrogen, the volume ratio of hydrogen and nitrogen is 2.5:1, and temperature is 175 DEG C, and unstripped gas enters heat exchanger tube3 air speed is 10000h-1, pressure 10MPa.Hot(test)-spot temperature in catalyst bed 5 is 400~480 DEG C, pressure 10MPa.Through detecting, the temperature into the unstripped gas of the second raw material gas inlet 51 is 360~390 DEG C；After the reaction of collection catalyst bedThe gas of outlet end 62 is detected, and the synthesis ammonia conversion ratio of this technique is greater than 17.5%
Embodiment 5
The reaction process of the reactors for synthesis of ammonia of the offer of embodiment 3 is be provided.To the first raw material gas inlet 21It is passed through the gaseous mixture of hydrogen and nitrogen, the volume ratio of hydrogen and nitrogen is 3:1, and temperature is 170 DEG C, and unstripped gas enters heat exchanger tube 3Air speed be 8000h-1, pressure 10MPa.Hot(test)-spot temperature in catalyst bed 5 is 410~450 DEG C, pressure 10MPa.ThroughDetection, the temperature into the unstripped gas of the second raw material gas inlet 51 are 380~400 DEG C；Going out after the reaction of collection catalyst bedThe gas at mouth end 62 is detected, and the synthesis ammonia conversion ratio of this technique is greater than 18%
Embodiment 6
The reaction process of the reactors for synthesis of ammonia of the offer of embodiment 3 is be provided.To the first raw material gas inlet 21It is passed through the gaseous mixture of hydrogen and nitrogen, the volume ratio of hydrogen and nitrogen is 3:1, and temperature is 180 DEG C, and unstripped gas enters heat exchanger tube 3Air speed be 15000h-1, pressure 9MPa.Temperature in catalyst bed 5 is 420~440 DEG C, pressure 9MPa.Through detecting,Temperature into the unstripped gas of the second raw material gas inlet 51 is 390~400 DEG C；Outlet end 62 after the reaction of collection catalyst bedGas detected, the synthesis ammonia conversion ratio of this technique is greater than 17%
Obviously, the above embodiments are merely examples for clarifying the description, and does not limit the embodiments.It is rightFor those of ordinary skill in the art, can also make on the basis of the above description it is other it is various forms of variation orIt changes.There is no necessity and possibility to exhaust all the enbodiments.And it is extended from this it is obvious variation orIt changes still within the protection scope of the invention.