CN103787695A - Ammonium polyphosphate agricultural fertilizer granulating technology - Google Patents
Ammonium polyphosphate agricultural fertilizer granulating technology Download PDFInfo
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- CN103787695A CN103787695A CN201410059098.8A CN201410059098A CN103787695A CN 103787695 A CN103787695 A CN 103787695A CN 201410059098 A CN201410059098 A CN 201410059098A CN 103787695 A CN103787695 A CN 103787695A
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Abstract
The invention belongs to the field of fertilizer, and particularly relates to an ammonium polyphosphate agricultural fertilizer granulating technology. The ammonium polyphosphate agricultural fertilizer granulating technology comprises the following steps: adding phosphoric acid into a tubular reactor, introducing ammonia under turbine stirring, and reacting, so as to obtain an ammonium polyphosphate solution; regulating the falling speed of granules in a collecting plate, then spraying the ammonium polyphosphate solution onto the falling granules, carrying out cooling action of reverse airflow in a roller so as to form particulate matters, discharging the particulate matters from the roller, feeding the particulate matters into a rotating cooler and cooling; screening the cooled particulate matters in a screening device, thus finally obtaining the product. The ammonium polyphosphate agricultural fertilizer granulating technology has the characteristics of being low in energy consumption, pollution-free, and easy to operate; the prepared agricultural fertilizer is excellent in granule quality, hard in texture, low in moisture content, and good in granule structure and maintains more polyphosphate content.
Description
Technical field
The invention belongs to fertilizer field, be specifically related to a kind of ammonium polyphosphate agricultural fertilizer granulation process.
Background technology
Along with the raising of suitability for industrialized production to product requirement, the particularly development of fertilizer industry, people generally require to produce large-particle fertilizer (particle diameter 4-8mm), large-particle fertilizer because granularity is large, intensity is high is suitable for forest, grassland plant seeds by airplane, oversize granule urea (particle diameter is 8-12mm) can be used as the deep layer base fertilizer in rice field, and large-particle fertilizer is also easy to package storage and transportation simultaneously.
Modern agriculture is not only quantity to the requirement of chemical fertilizer, and requires suitability good.Require and obtain better economic benefit for meeting user, generally to base fertilizer, as urea, ammonium phosphate etc., carry out secondary processing and make Chemical Mixed Fertilizer.The production method of Chemical Mixed Fertilizer has slurry process, blending method, melting method, granulating method etc.At present, maximum compound fertilizer production method that China is used is granulating method, has the shortcomings such as technical process is long, energy consumption is higher, and therefore, granulation process needs further perfect in production from now on.
The 3rd, in 153, No. 574 United States Patent (USP)s, the people such as Achorn have proposed a kind of technique that uses phosphoric acid by wet process and ammonia to produce Secondary ammonium phosphate, but this technique needs pre-neutralization and a large pre-neutralization tank.
The 3rd, 985, in No. 538 United States Patent (USP)s, the people such as Hicks have proposed a kind of technique of producing particulate state ammonium polyphosphate fertilizer, in a tubular reactor, prepare ammonium polyphosphate solute, go up the injection of a series of apertures by Guan Bi, little fertilizer particulate is frozen into particulate matter, but this needs a pre-neutralization step equally.
The 4th, in 134, No. 750 United States Patent (USP)s, the people such as Norton have proposed a kind of technique of producing tertiary iron phosphate, ammonium phosphate sulfate and urea ammonium phosphate sulfate with pipe staggered form reactor.They introduce sulfuric acid in pipe staggered form reactor.Reach more than 30% poly-phosphate to obtain concentration in end product.Because material cost comprises the expense of a large amount of sulfuric acid, and the high corrosion environment that causes of sulfuric acid, need to build relevant device, input cost is too large.
The 4th, in 337, No. 079 United States Patent (USP)s, the people such as Mann have adopted a kind of amplifying tube staggered form reactor, produce the lysate that polyphosphate content is 20%-30% under the prerequisite of not adding sulfuric acid.They attempt these lysate granulatings, but therefrom produce suspended substance.Their amplification tubular reactor is lower than 20psig(pound/square inch) pressure under move, that is to say, avoid the loss of ammonia thereby these tubular reactors need to sink to operation in liquid.Trivial operations is serious to reactor corrosion.
At the 2nd of Smith, 926, No. 079 United States Patent (USP)s, and in the 2nd, 798, No. 801 United States Patent (USP) techniques of the people such as Kieffer, all need a baking step to remove unnecessary moisture.The people such as Hamsley, the 3rd, 415, require to use water knockout in the technique of No. 638 United States Patent (USP)s.
Domestic production large-particle fertilizer is mainly fluidized bed prilling technology and the double rotating drum agglomeration technique of Norway's Hydro at present, but one-time investment and process cost are higher, handiness is poor, can only carry out granulation to limited fertilizer variety, aspect environmental protection, dust pollution is serious, and the physical strength of particle is relatively poor.Therefore, existing prilling process is unsatisfactory at the aspect such as physical strength, particle diameter of particle, and invests in addition the problems such as high, seriously polluted, trivial operations, and the novel granulation process of researchdevelopment is urgently to be resolved hurrily.
Summary of the invention
The object of this invention is to provide a kind of ammonium polyphosphate agricultural fertilizer granulation process, low power consuming, pollution-free, easy to operate, the agricultural fertilizer particle that makes is best in quality, quality is hard, water content is low, grain pattern is good.
Ammonium polyphosphate agricultural fertilizer granulation process of the present invention, step is as follows:
(1) in tubular reactor, add phosphoric acid, under turbine stirring, pass into ammonia gas react, obtain polyphosphoric acid ammonium solution;
(2) regulate the falling velocity of particle in catch tray, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form particulate matter, the water cooler that particulate matter enters rotation from cylinder discharge is cooling;
(3) cooled particulate matter is screened in screening plant, and the particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper, and the particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, finally obtains product.
The temperature of the phosphoric acid described in step (1) is 200-205 ℃.
Reaction pressure described in step (1) is 0.27-0.32Mpa, and temperature of reaction is 200-205 ℃, and the reaction times is 20-25min.
The mode that adds phosphoric acid described in step (1) is to add with the speed of 14-16kg per hour.
The mol ratio of the phosphoric acid described in step (1) and ammonia is 1:1-1.2.
Falling velocity described in step (2) is 55-60kg/h.
The temperature of the back draught described in step (2) is 25-28 ℃.
Described in step (2), be cooled to 25-28 ℃.
The equipment of described ammonium polyphosphate agricultural fertilizer granulation process comprises cylinder, water cooler and screening plant, and cylinder, water cooler and screening plant are connected successively.
Described cylinder comprises cylindrical shell, and equalization is provided with material delivering plate inside barrel wall, and centre of the drum is provided with tubular reactor, and tubular reactor communicates with nozzle, between tubular reactor and material delivering plate, is provided with catch tray.
In the present invention, proposed a kind ofly by wet method and ammonification, phosphoric acid to be reacted to produce the improvement technique of agricultural fertilizer, granulating of the present invention occurs in the swing roller with internals.Internals comprises material delivering plate, inclination catch tray and sprinkling system.Particulate matter is promoted by material delivering plate, after a bit of distance that falls, falls on catch tray, then arrives cylinder top.Particulate matter is curtain shape under the effect of inclination catch tray.Then the ammonium polyphosphate having dissolved is directly sprayed onto on granuloplastic curtain.After the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form the particulate matter of moderate dimensions.
Through whereabouts curtain and in the process of particle coating, can effectively reduce required a large amount of chemicals and free-water at lysate, reach the major objective of technique of the present invention.
The present invention has used the tubular reactor of an amplification, but to its pressurization and remain on 0.35MPa, to realize good solid ammonia effect, and spray coating in the process falling at carrier granule, but do not use fan, do not add water, do not need a large amount of material delivering plates or plate yet.
The present invention be first by wet process acid in preheater with steam preheating to 200 ℃, then by heating after acid in the tubular reactor of a pressurization, carry out ammonification and the anhydrous solution of generation be directly sprayed onto on the regenerated granule that contains identical component solution with pipe.
The reaction in the tubular reactor of pressurization of ammonia and phosphoric acid produces heat, and free-water evaporates from reactant, removes whole free-waters and part constitution water in phosphoric acid, produces substantially water-free solution.Because water-free spray solution has arrived on the regrowth of granulation cylinder, therefore in technique of the present invention without drying process.Between particulate matter, can not produce caking yet.Tubular reactor must be pressurized to about 0.35MPa, so as in granulation cylinder by spray solution to falling on granuloplastic curtain.Test case proves in early days, and the hydrolytic action degree of the poly-phosphate causing in technological process is directly proportional to the retention time of solution in reactor, has therefore replaced pressurizing vessel with tubular reactor.
With the 3rd, 153, No. 574 United States Patent (USP) is compared, the present invention has cancelled this step independently of the solid-state ammonium phosphate of oven dry that needs in the people's such as Achorn technique, cancel expensive baking step, reduced investment and running cost, and significantly reduced energy requirement, the problem that must consider decontamination in the people's such as while Achorn technique is also greatly simplified in technique of the present invention.
With the 3rd, 985, No. 538 United States Patent (USP) is compared, and has cancelled this step of pre-neutralization in the present invention, and required other reactions, transmission and metering outfit etc. thereupon.
With the 2nd of Smith, 926, No. 079 United States Patent (USP)s, and the 2nd, 798, No. 801 United States Patent (USP)s of the people such as Kieffer compare, and in technique of the present invention, have save baking step.In technique of the present invention, also cancel a pressurization steps, and required specific installation thereupon, if the people such as Hamsley are the 3rd, 415, in the technique of No. 638 United States Patent (USP)s, require the water knockout using.
The present invention compared with prior art, has following beneficial effect:
The present invention has low power consuming, pollution-free, easy-operating feature, and the agricultural fertilizer particle that makes is best in quality, quality is hard, water content is low, grain pattern is good and kept more polyphosphate content.
Accompanying drawing explanation
Fig. 1 is process flow sheet of the present invention;
Fig. 2 is the structural representation of cylinder;
In figure: 1, cylindrical shell; 2, material delivering plate; 3, catch tray; 4, tubular reactor; 5, nozzle.
Embodiment
Below in conjunction with embodiment, the present invention is described further.
(1) in tube container, ortho-phosphoric acid is carried out to ammonification, add the hot phosphoric acid of 200 ℃ with the speed of 14kg per hour, under turbine stirring, pass into ammonia, and make pressure remain on 0.29Mpa, Heating temperature maintains 200 ℃, reaction 20min,
(2) regulate the falling velocity of particle in particle disc, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form the particulate matter of moderate dimensions, particulate matter is discharged the water cooler that enters a rotation from cylinder.
(3) then product is divided into 5 streamlines and screens to reject out-of-size product.The particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper.The particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, finally obtains product.
The particle diameter of particle is 4.5mm after testing, N content 10.5%, P
2o
5content 52.6%.
(1) in tube container, add the hot phosphoric acid of 205 ℃ with the speed of 16kg per hour, under turbine stirring, pass into ammonia, and make pressure remain on 0.31Mpa, Heating temperature maintains 201 ℃, reaction 23min,
(2) regulate the falling velocity of particle in particle disc, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form the particulate matter of moderate dimensions.Particulate matter is discharged the water cooler that enters a rotation from cylinder.
(3) then product is divided into 5 streamlines and screens to reject out-of-size product.The particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper.The particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, obtains product.
The particle diameter of particle is 5mm after testing, N content 11.1%, P
2o
5content 56.6%.
(1) in tube container, add the hot phosphoric acid of 203 ℃ with the speed of 15kg per hour, under turbine stirring, pass into ammonia, and make pressure remain on 0.32MPa, Heating temperature maintains 205 ℃, reaction 25min,
(2) regulate the falling velocity of particle in particle disc, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form the particulate matter of moderate dimensions.Particulate matter is discharged the water cooler that enters a rotation from cylinder.
(3) then product is divided into 5 streamlines and screens to reject out-of-size product.The particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper.The particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, obtains product.
The particle diameter of particle is 4.8mm after testing, N content 10.1%, P
2o
5content 50.6%.
Embodiment 4
(1) in tube container, add the hot phosphoric acid of 200 ℃ with the speed of 16kg per hour, under turbine stirring, pass into ammonia, and make pressure remain on 0.28Mpa, Heating temperature maintains 200 ℃, reaction 20min,
(2) regulate the falling velocity of particle in particle disc, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form the particulate matter of moderate dimensions, particulate matter is discharged the water cooler that enters a rotation from cylinder.
(3) then product is divided into 5 streamlines and screens to reject out-of-size product.The particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper.The particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, obtains product.
The particle diameter of particle is 5.8mm after testing, N content 13.1%, P
2o
5content 66.6%.
(1) in tube container, add the hot phosphoric acid of 200 ℃ with the speed of 16kg per hour, under turbine stirring, pass into ammonia, and make pressure remain on 0.27Mpa, Heating temperature maintains 200 ℃, reaction 20min,
(2) regulate the falling velocity of particle in particle disc, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form the particulate matter of moderate dimensions, particulate matter is discharged the water cooler that enters a rotation from cylinder.
(3) then product is divided into 5 streamlines and screens to reject out-of-size product.The particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper.The particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, obtains product.
The particle diameter of particle is 6.7mm after testing, N content 23.1%, P
2o
5content 67.6%.
To the fertiliser granulates test of producing, product particle is rounded, and size distribution is even, and without the accumulation of fine particle, initial water content is 0.1%-0.4%, and physical strength is better.
Claims (10)
1. an ammonium polyphosphate agricultural fertilizer granulation process, is characterized in that step is as follows:
(1) in tubular reactor, add phosphoric acid, under turbine stirring, pass into ammonia gas react, obtain polyphosphoric acid ammonium solution;
(2) regulate the falling velocity of particle in catch tray, then by ammonium polyphosphate solution spraying to fall particle on, after the cooling effect of back draught in cylinder, on the particle spraying, cover thin film and be cured, form particulate matter, the water cooler that particulate matter enters rotation from cylinder discharge is cooling;
(3) cooled particulate matter is screened in screening plant, and the particulate matter of particle diameter 3.5-4mm can be collected into granulation again in surge hopper, and the particulate matter of particle diameter 7.5-8mm is crushed and return in screening plant, finally obtains product.
2. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that the temperature of the phosphoric acid described in step (1) is 200-205 ℃.
3. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that the reaction pressure described in step (1) is 0.27-0.32Mpa, and temperature of reaction is 200-205 ℃, and the reaction times is 20-25min.
4. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, the mode that adds phosphoric acid described in step (1) that it is characterized in that is to add with the speed of 14-16kg per hour.
5. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that the mol ratio of the phosphoric acid described in step (1) and ammonia is 1:1-1.2.
6. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that the falling velocity described in step (2) is 55-60kg/h.
7. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that the temperature of the back draught described in step (2) is 25-28 ℃.
8. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that being cooled to 25-28 ℃ described in step (2).
9. ammonium polyphosphate agricultural fertilizer granulation process according to claim 1, is characterized in that the equipment of described ammonium polyphosphate agricultural fertilizer granulation process comprises cylinder, water cooler and screening plant, and cylinder, water cooler and screening plant are connected successively.
10. ammonium polyphosphate agricultural fertilizer granulation process according to claim 9, it is characterized in that described cylinder comprises cylindrical shell, inside barrel wall, equalization is provided with material delivering plate, centre of the drum is provided with tubular reactor, tubular reactor communicates with nozzle, between tubular reactor and material delivering plate, is provided with catch tray.
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| CN201410059098.8A CN103787695A (en) | 2014-02-21 | 2014-02-21 | Ammonium polyphosphate agricultural fertilizer granulating technology |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104959072A (en) * | 2015-07-16 | 2015-10-07 | 三峡大学 | Water supply and control integrated disc granulator |
| CN105776166A (en) * | 2016-02-04 | 2016-07-20 | 谢义蓉 | Method for preparing ammonium polyphosphate particles |
| CN107602240A (en) * | 2017-10-16 | 2018-01-19 | 王欣 | A kind of production method of the microbial manure comprising bacillus subtilis |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2926079A (en) * | 1955-08-09 | 1960-02-23 | Chemical & Ind Corp | Process for production of fertilizer pellets |
| US4601891A (en) * | 1985-10-15 | 1986-07-22 | Tennessee Valley Authority | Production of granular ammonium polyphosphate from wet-process phosphoric acid |
| CN102219591A (en) * | 2011-05-19 | 2011-10-19 | 武汉市中东化工有限公司 | Method of producing sulfur-based high nitrogen composite fertilizer by spray granulation |
| CN102603387A (en) * | 2012-03-19 | 2012-07-25 | 深圳市芭田生态工程股份有限公司 | Method for producing compound fertilizer by high tower tubular reactor |
-
2014
- 2014-02-21 CN CN201410059098.8A patent/CN103787695A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2926079A (en) * | 1955-08-09 | 1960-02-23 | Chemical & Ind Corp | Process for production of fertilizer pellets |
| US4601891A (en) * | 1985-10-15 | 1986-07-22 | Tennessee Valley Authority | Production of granular ammonium polyphosphate from wet-process phosphoric acid |
| CN102219591A (en) * | 2011-05-19 | 2011-10-19 | 武汉市中东化工有限公司 | Method of producing sulfur-based high nitrogen composite fertilizer by spray granulation |
| CN102603387A (en) * | 2012-03-19 | 2012-07-25 | 深圳市芭田生态工程股份有限公司 | Method for producing compound fertilizer by high tower tubular reactor |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104959072A (en) * | 2015-07-16 | 2015-10-07 | 三峡大学 | Water supply and control integrated disc granulator |
| CN104959072B (en) * | 2015-07-16 | 2017-01-18 | 三峡大学 | Water supply and control integrated disc granulator |
| CN105776166A (en) * | 2016-02-04 | 2016-07-20 | 谢义蓉 | Method for preparing ammonium polyphosphate particles |
| CN105776166B (en) * | 2016-02-04 | 2018-03-02 | 谢义蓉 | A kind of preparation method of ammonium polyphosphate particles |
| CN107602240A (en) * | 2017-10-16 | 2018-01-19 | 王欣 | A kind of production method of the microbial manure comprising bacillus subtilis |
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Application publication date: 20140514 |