CN1226544A - Method and apparatus for producing diammonium phosphate with external circulation ammoniation reactor - Google Patents
Method and apparatus for producing diammonium phosphate with external circulation ammoniation reactor Download PDFInfo
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- CN1226544A CN1226544A CN 99101150 CN99101150A CN1226544A CN 1226544 A CN1226544 A CN 1226544A CN 99101150 CN99101150 CN 99101150 CN 99101150 A CN99101150 A CN 99101150A CN 1226544 A CN1226544 A CN 1226544A
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- phosphoric acid
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- C05—FERTILISERS; MANUFACTURE THEREOF
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- C05B7/00—Fertilisers based essentially on alkali or ammonium orthophosphates
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Abstract
A process for preparing diammonium phosphate with ammoniating reactor using external recirculating uses such apparatuses as ammoniating reactor using external recirculating, Venturi washer, material slurry tank and material slurry circulation system. The tail gas after reaction can be discharged after washed through Venturi washer where concentrated phosphoric acid is used as washing liquid. Said washing liquid is added to reactor from its top, where it takes part in neutralizing reaction with ammonia. The part of material slurry overflowed from reactor to material slurry tank is used to spray granulation and the rest is pumped back to reactor for increasing the flowability of materials. Its advantages include short technological route, high utilization rate of ammonia, stable running and not being blocked easily.
Description
The present invention relates to a kind ofly produce the method for phosphorus ammonium and realize the device of this method with loop reactor, specifically a kind of with producing diammonium phosphate with external circulation ammoniation reactor method and realize the device of this method.
Loop reactor divides two kinds of common loop reactor and external loop reactors, its principle of work is to utilize the apparent density official post material of material in upcast and the downtake to circulate, adopt the circulation ammoniation reactor to produce the phosphorus ammonium, its advantage is that flow process is simple, the reaction times is short, equipment volume is little, floor space is few, reduced investment, simple to operate, stable, energy consumption is low.Interior circulation ammoniation reactor is mutually nested because of inside and outside concentric tube, is unfavorable for field-strip.The external circulation ammoniation reaction is that the quick ammonification vaporizer of USSR (Union of Soviet Socialist Republics) exploitation can overcome aforesaid drawbacks, the technical process of producing monoammonium phosphate with this reactor as shown in Figure 1, phosphoric acid or nitration mixture are joined in the phosphoric acid storage tank 1 by outer operation, by pump 2 it is delivered in the bottom adding ammoniation reactor 4 of interchanger 3 heat absorption backs by downtake again, ammonia is added by the upcast bottom, reaction end gas is discharged by reactor 4 tops and is delivered to interchanger 3 coolings by pipeline, feed the ammonia in the washing absorption tail gas in the phosphoric acid storage tank 1 again, tail gas after the washing also needs purifying treatment, reaction slurry overflow in the ammoniation reactor is to slip receiving tank 6, concentrate by the pumping devaporation again, obtain the finished product, 5 is the phlegma storage tank.Because the degree of neutralization of monoammonium phosphate is low, about 1.1, temperature of reaction is low, and about 105 ℃, the Flow of Goods and Materials performance is good, and the effusion rate of ammonia is lower in the tail gas, and therefore, this technology is suitable for producing monoammonium phosphate.Because the degree of neutralization height of production diammonium phosphate, generally about 1.5, temperature of reaction is higher, and about 120 ℃, slip viscosity is big, mobile poor, thereby, produce the effusion rate height that two ammoniums certainly exist ammonia in the tail gas with this processing method, reclaim difficulty, the utilization ratio of ammonia is low, shortcomings such as the easy obstruction of slip system.
The purpose of this invention is to provide a kind of with producing diammonium phosphate with external circulation ammoniation reactor method and be used to realize the device of this method, can reduce the content of the ammonia in the tail gas, improve the utilization ratio of ammonia, slip is difficult for stopping up simultaneously.
The present invention comprises the following steps: with the method for producing diammonium phosphate with external circulation ammoniation reactor
(1) with 32-38%P
2O
5Phosphoric acid is sent in the rinse bath, delivers to the acid-adding port that is located at ammoniation reactor top by rinse bath again and adds in the ammoniation reactor in the spray mode;
(2) in pipe, feed steam heating by the ammonification mouth that is located at ammoniation reactor upcast bottom;
(3) treat that phosphoric acid is full of the volume space of ammoniation reactor reaction zone, when the phosphoric acid temperature rises to 80-100 ℃, in pipe, add gas ammonia by the ammonification mouth, phosphoric acid and gas ammonia carry out neutralization reaction, temperature of reaction is controlled at about 100-120 ℃, the slip degree of neutralization is controlled at about 1.4-1.55, and reaction back slip is flowed out in the slurry vessel by upflow tube, and reaction end gas is overflowed by ammoniation reactor top;
(4) above-mentioned reaction end gas is fed in the rinse bath tail gas emptying after the washing;
(5) the part slip that will flow in the slurry vessel in the Returning reactor, is managed the flowability of interior slip with recycle pump with raising bottom the downtake of ammoniation reactor;
(6) the other part slip in the slurry vessel is sent to dispute slurry, granulation, obtain desired product.
Be used to realize that the device of the inventive method comprises:
An external circulation ammoniation reactor is used for phosphoric acid and ammonia are carried out neutralization reaction, and the top of described reactor is provided with and adds sour nozzle, on pipe falls and the bottom be provided with the ammonification mouth;
A slurry vessel is used for collecting by the effusive reaction slurry of ammoniation reactor overflow port;
A slurry circulation pump is used for a part of slip in the slurry vessel is sent back in the downtake of ammoniation reactor, to improve slip flowability in the pipe;
A rinse bath is used for holding the reaction end gas that phosphoric acid and washing are come out by ammoniation reactor;
One adds sour passage, and the phosphoric acid in the rinse bath is delivered to sour nozzle of adding of ammoniation reactor;
A spray granulating device is used for the other part slip in the slurry circulation groove is carried out spray granulating, obtains diammonium phosphate product.
In order to strengthen the washing tail gas effect, improve the transformation efficiency and the rate of recovery of ammonia, in preferred version of the present invention, also comprise a Venturi tube, be used for washing reaction end gas, and liquid vapour mixture is sent in the rinse bath from ammoniation reactor; A cleaning circulation pump is used for the phosphoric acid in the rinse bath is delivered to the fluid inlet of Venturi tube.
In order to utilize the dried tail gas washing dilute phosphoric acid in the spray granulating operation and to regulate the slip solid content, the washing diluted acid of self-desiccation tail gas mixes in adding sour passage with the strong phosphoric acid from rinse bath in the future, form nitration mixture, join in the ammoniation reactor by adding sour nozzle again.
Because the present invention has changed and has added sour point, phosphoric acid is added by ammoniation reactor top spray, thereby the upper strata phosphor ammonium slurry is the slip of the low degree of neutralization of one deck in reactor, make the spillage of ammonia significantly reduce, simultaneously, phosphoric acid also ammonia in the absorption portion reaction end gas in the spray process, the reaction end gas of overflowing from ammoniation reactor washs with the higher Venturi scrubbing device of detersive efficiency, can make the tail gas qualified discharge, need not remake purifying treatment, not only technical process is shortened, and the utilization ratio of ammonia improves.Set up a recycle pump between slurry vessel and downtake, can improve the flow condition of slip, improve the circulation ratio of slip, increase less turbulence, production operation elasticity improves greatly, makes device stable, is difficult for stopping up.
Fig. 1 produces the monoammonium phosphate process flow sheet for the external circulation ammoniation reactor of USSR (Union of Soviet Socialist Republics) exploitation.
Fig. 2 is a process flow sheet of the present invention.
Below in conjunction with accompanying drawing the present invention is described in detail:
34-36%P
2O
5Phosphoric acid add the rinse baths 11 by the nozzle 8 that pipeline 7 is provided with in from outer operation pump to Venturi tube 9 expansion sections, and 21 add in the reactors through adding sour passage 13 and being located at adding of ammoniation reactor 4 tops sour nozzle by rinse bath 11 overflows, during to 23 overflows of ammoniation reactor upflow tube, start cleaning circulation pump 12, feed the steam of sending here by pipeline 15 by the ammonification mouth that is located at upcast 14 bottoms again, phosphoric acid is heated to 80-100 ℃ in will managing, begin to feed from the pressure of ammonia evaporator 16 gas ammonia greater than 0.18MPa, phosphoric acid and gas ammonia carry out neutralization reaction in upcast 14, reaction heat makes slurry temperature raise and density decline, thereby promoting slip Rapid Cycle in upcast 14 and downtake 17 flows, reaction end gas in ammoniation reactor 4 after adding the phosphoric acid washing under sour nozzle 21 sprays, be expelled to the inlet mouth of Venturi tube 9 by the top, absorb washing by cleaning circulation pump 12 strong phosphoric acid that pump comes from rinse bath 11, and the fresh strong phosphoric acid that is sprayed into by the nozzle in expansion section 8 is further after the washing, send in the rinse bath, tail gas is from venting hole 10 emptyings of rinse bath top, and wherein ammonia content can be reduced to 12.56mg/m
3The strong phosphoric acid that has absorbed the ammonia in the tail gas through washing overflows rinse bath again, add in the reactor 4 by nozzle 21 by adding sour passage 13, simultaneously, reaction slurry in the ammoniation reactor by upflow tube 23 overflows to slurry vessel 20, when the slip liquid level in the slurry vessel 20 reaches 1/3, start slurry circulation pump 18, a part of slip is sent in the pipe by downtake 17 bottoms, another part slip is sent to whitewashing, granulation by spray granulating pump 19.
Phosphoric acid concentration 32-38%P in the present invention
2O
5All can move, more suitable with 34-36%, too high viscosity increases, and neutralization back slip water-content reduces the material fluidity variation.The slip degree of neutralization is comparatively suitable with 1.4-1.55, and is better with 1.45-1.5, and cross the low production nutrient and do not reach requirement, too high material fluidity variation, the tail gas ammonia quantity increases, easily fouling and obstruction.Material residence time in ammoniator is suitable, too short with about 5-8 minute, and ammonia absorbs insufficient, and the ammonia utilization ratio is low, and the excessive ammonification of too high meeting is degenerated, and influences quality product.Temperature of reaction can be controlled at about 100-120 ℃ by regulating ammonia residual, cross low meeting and reduce degree of neutralization, the escaped quantity of too high ammonia is big, is unfavorable for the recovery of ammonia.
Because temperature of reaction is higher, the reaction slurry evaporation concentration, make the slip solid content strengthen, the mobile variation of material, be unfavorable for spray granulating again,, the dried tail gas from the whitewashing granulating working procedure can be washed dilute phosphoric acid by pipeline 22 in order to reduce solid content, join in the sour passage 13 and mix the formation nitration mixture, join in the reactor 4 by adding sour nozzle 21 again with the effusive phosphoric acid of rinse bath.
The liquid level of above-mentioned slurry vessel 20 generally is controlled at about 1/3-2/3, guarantee to collect in the slurry vessel a certain amount of slip is arranged, when the degree of neutralization of the reaction slurry that overflows when ammoniation reactor was too high or too low like this, the slip in the slurry vessel can play fine setting and buffering effect to degree of neutralization.
Claims (9)
1, a kind of method with producing diammonium phosphate with external circulation ammoniation reactor comprises the steps:
(1) with 32-38%P
2O
5Phosphoric acid is sent in the phosphoric acid washing groove, delivers to the acid-adding port that is located at ammoniation reactor top through rinse bath again and adds in the ammoniation reactor in the spray mode;
(2) in pipe, feed steam heating by the ammonification mouth that is located at ammoniation reactor upcast bottom;
(3) phosphoric acid is full of the reaction zone space in the question response device, when the phosphoric acid temperature rises to 80-100 ℃, in upcast, add gas ammonia by the ammonification mouth, acid ammonia carries out neutralization reaction, temperature of reaction is controlled at 100-120 ℃, the slip degree of neutralization is controlled at 1.4-1.55, and reaction slurry is flowed out in the slurry vessel by the upflow tube that is located on the ammoniation reactor, and reaction end gas is discharged by ammoniation reactor top;
(4) reaction end gas in the step (3) is fed in the phosphoric acid washing groove tail gas emptying after the washing;
(5) the slip part in the slurry vessel is delivered to ammoniation reactor downtake bottom by recycle pump, to add the flowability of slip in the bassoon;
(6) another part slip in the slurry vessel is sent to whitewashing, granulation, obtain desired product.
2, method according to claim 1, will by rinse bath be sent to aminating reaction acid-adding port phosphoric acid with mixes from granulating working procedure dried tail gas washing dilute phosphoric acid after, again by in the acid-adding port adding ammoniation reactor.
3, method according to claim 1 and 2, wherein the described phosphoric acid of step (1) is with 34-36%P
2O
5Phosphoric acid is better, and the described degree of neutralization of step (3) is better with 1.45～1.5.
4, method according to claim 3, wherein the described reaction end gas of step (4) is delivered in the rinse bath after being absorbed as the Venturi tube of absorption liquid by the phosphoric acid washing liquid in the rinse bath again.
5, method according to claim 4, wherein the described phosphoric acid of step (1) is added by the expansion section of Venturi tube.
6, a kind of device that is used to realize the described method of claim 1 comprises:
An external circulation ammoniation reactor is used for phosphoric acid and ammonia are carried out neutralization reaction, and the top of described reactor is provided with and adds sour nozzle; The middle part is provided with the slip overflow port, and the bottom of upcast is provided with the ammonification mouth;
A slurry vessel is used for collecting by the effusive reaction slurry of above-mentioned ammoniation reactor overflow port;
A slurry circulation pump is used for the bottom of the part shurry pump in the slurry vessel to the ammoniation reactor downtake, to add the flowability of slip in the bassoon;
A rinse bath is used for containing phosphoric acid and the washing reaction end gas from ammoniation reactor;
One adds sour passage, and the phosphoric acid that rinse bath overflows is delivered to sour nozzle of adding of ammoniation reactor;
A spray granulating device, be used for the other part slip in the slurry vessel whitewash, granulation, obtain diammonium phosphate product.
7, device according to claim 6, it is characterized in that also comprising one with add the diluted acid passage that sour passage communicates, be used in the future self-desiccation washing tail gas dilute phosphoric acid with mixes afterwards the adding ammoniation reactor from the strong phosphoric acid of rinse bath.
8, according to claim 6 or 7 described devices, it is characterized in that also comprising a Venturi tube, be used for washing reaction end gas, and liquid vapour mixture is delivered to rinse bath from ammoniation reactor; A cleaning circulation pump is used for the phosphoric acid in the rinse bath is delivered to the fluid inlet of Venturi tube.
9, device according to claim 8 is characterized in that setting adds sour nozzle in the expansion section of Venturi tube, is used for washing by the ammonia in the Venturi tube tail gas discharged and in rinse bath replenishing phosphoric acid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN99101150A CN1084316C (en) | 1999-01-15 | 1999-01-15 | Method and apparatus for producing diammonium phosphate with external circulation ammoniation reactor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN99101150A CN1084316C (en) | 1999-01-15 | 1999-01-15 | Method and apparatus for producing diammonium phosphate with external circulation ammoniation reactor |
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| CN1226544A true CN1226544A (en) | 1999-08-25 |
| CN1084316C CN1084316C (en) | 2002-05-08 |
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| CN99101150A Expired - Fee Related CN1084316C (en) | 1999-01-15 | 1999-01-15 | Method and apparatus for producing diammonium phosphate with external circulation ammoniation reactor |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1331749C (en) * | 2004-07-23 | 2007-08-15 | 四川大学 | Tech. for ammoniating integration of acid material fluidifying |
| CN100371238C (en) * | 2006-06-16 | 2008-02-27 | 四川川大中德环保技术有限公司 | Method for producing diammonium phosphate by concentrating acid slime, and secondary ammoniation reactor |
| CN102491297A (en) * | 2011-11-30 | 2012-06-13 | 湖北三宁化工股份有限公司 | Method for producing ammonium sulfate in S-NPK device by using refined phosphoric acid byproduct tail liquid |
| CN102503648A (en) * | 2011-11-30 | 2012-06-20 | 湖北三宁化工股份有限公司 | Method for producing ammonium phosphate sulfate by S-NPK (Sulfur-Containing Nitrogen-Phosphorus-Potassium Compounds) device |
| CN102951622A (en) * | 2012-10-18 | 2013-03-06 | 陕西比迪欧化工有限公司 | Preparation method of diammonium phosphate by acid slurry co-production |
| CN103086751A (en) * | 2013-01-30 | 2013-05-08 | 湖北三宁化工股份有限公司 | Device and process for producing diammonium phosphate by using monoammonium phosphate device and sulfur-based compound fertilizer device |
| CN104511239A (en) * | 2013-12-18 | 2015-04-15 | 广西鹿寨化肥有限责任公司 | Method for improving washing effect of ammonium phosphate granulation tail gas |
| CN114669264A (en) * | 2022-04-08 | 2022-06-28 | 长沙鑫本药业有限公司 | Device and method for producing ammonium formate by adopting external circulation ammoniation |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1176079B (en) * | 1984-04-18 | 1987-08-12 | Anic Agricoltura Spa | PROCEDURE FOR THE PRODUCTION OF WATER SOLUBLE AMMONIUM PHOSPHATES |
| CN1042216C (en) * | 1992-07-17 | 1999-02-24 | 莱西市磷肥厂 | Enriching slurry process for production of diammonium phosphate |
-
1999
- 1999-01-15 CN CN99101150A patent/CN1084316C/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1331749C (en) * | 2004-07-23 | 2007-08-15 | 四川大学 | Tech. for ammoniating integration of acid material fluidifying |
| CN100371238C (en) * | 2006-06-16 | 2008-02-27 | 四川川大中德环保技术有限公司 | Method for producing diammonium phosphate by concentrating acid slime, and secondary ammoniation reactor |
| CN102491297A (en) * | 2011-11-30 | 2012-06-13 | 湖北三宁化工股份有限公司 | Method for producing ammonium sulfate in S-NPK device by using refined phosphoric acid byproduct tail liquid |
| CN102503648A (en) * | 2011-11-30 | 2012-06-20 | 湖北三宁化工股份有限公司 | Method for producing ammonium phosphate sulfate by S-NPK (Sulfur-Containing Nitrogen-Phosphorus-Potassium Compounds) device |
| CN102503648B (en) * | 2011-11-30 | 2013-08-07 | 湖北三宁化工股份有限公司 | Method for producing ammonium phosphate sulfate by S-NPK (Sulfur-Containing Nitrogen-Phosphorus-Potassium Compounds) device |
| CN102951622A (en) * | 2012-10-18 | 2013-03-06 | 陕西比迪欧化工有限公司 | Preparation method of diammonium phosphate by acid slurry co-production |
| CN102951622B (en) * | 2012-10-18 | 2014-10-01 | 陕西比迪欧化工有限公司 | Preparation method of diammonium phosphate by acid slurry co-production |
| CN103086751A (en) * | 2013-01-30 | 2013-05-08 | 湖北三宁化工股份有限公司 | Device and process for producing diammonium phosphate by using monoammonium phosphate device and sulfur-based compound fertilizer device |
| CN103086751B (en) * | 2013-01-30 | 2014-07-23 | 湖北三宁化工股份有限公司 | Device and process for producing diammonium phosphate by using monoammonium phosphate device and sulfur-based compound fertilizer device |
| CN104511239A (en) * | 2013-12-18 | 2015-04-15 | 广西鹿寨化肥有限责任公司 | Method for improving washing effect of ammonium phosphate granulation tail gas |
| CN114669264A (en) * | 2022-04-08 | 2022-06-28 | 长沙鑫本药业有限公司 | Device and method for producing ammonium formate by adopting external circulation ammoniation |
| CN114669264B (en) * | 2022-04-08 | 2023-09-05 | 长沙鑫本药业有限公司 | Device and method for producing ammonium formate by adopting external circulation ammonification |
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| Publication number | Publication date |
|---|---|
| CN1084316C (en) | 2002-05-08 |
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Applicant after: Anhui Liuguo Chemical Industry Co., Ltd. Applicant after: Sichuan Union Univ. Applicant after: No. 3 Design Inst., Ministry of Chemical Industry Applicant before: Tongling Chemical Industry Group Corporation Ammonium Plant Applicant before: Sichuan Union University Applicant before: the third design institute of the Ministry of Chemical Industry |
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Free format text: CORRECT: APPLICANT; FROM: TONGLING CHEMICAL INDUSTRIAL GROUP CO.,LTD. PHOSPHATE FACTORY; SICHUAN UNITED UNIVERSITY; NO.3 DESIGN INST., MINISTRY OF CHEMICAL INDUSTRY TO: ANHUI LIUGUO CHEMICAL CO.,LTD.; SICHUAN UNITED UNIVERSITY; NO.3 DESIGN INST., MINISTRY OF CHEMICAL INDUSTRY |
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Granted publication date: 20020508 Termination date: 20140115 |