CN101102980A - Urea composition having reduced compressibility, caking and dust formation, and process for its preparation - Google Patents
Urea composition having reduced compressibility, caking and dust formation, and process for its preparation Download PDFInfo
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- CN101102980A CN101102980A CN200680002294.5A CN200680002294A CN101102980A CN 101102980 A CN101102980 A CN 101102980A CN 200680002294 A CN200680002294 A CN 200680002294A CN 101102980 A CN101102980 A CN 101102980A
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- urea
- urea composition
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2/00—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
- B01J2/30—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic using agents to prevent the granules sticking together; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
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Abstract
A free-flowing, mineral oil-free granulate particles of a plant auxiliary agent comprises reaction product of a plant auxiliary agent containing nitrogen, phosphorus and/or potassium and a waste flow of natural material containing nitrogen compound(s). The plant auxiliary agent is a fertilizer containing urea or ammonium nitrate. The natural material is of vegetable or animal origin. An independent claim is included for preparing free-flowing, mineral oil free granulate particles of a plant auxiliary agent involving reacting a waste flow of natural material containing nitrogen compound with molten particles of plant auxiliary agent in presence of a solvent.
Description
Foreword
Urea granules fragmentation in preparation, storage and transportation is known.When urea granules as greater than 40 ℃ high relatively temperature under store or by sea when defeated, may be broken up to the urea granules of 25%b.w..Though this urea granules itself absorbs small amount of moisture, and in fact itself is insensitive to luming, and the crushed particles of high percent causes the caking trend of dust problem and accompanied by intense.
In addition because the pressure that exists in the bottom of a large amount of urea cause from the moving of particulate residual moisture, take place during a large amount of transportation of urea that the particulate agglomeration problems especially can be in the torrid areas.
Be known that also a lot of chemical compositions can be as the additive that improves crushing strength, caking trend and water-repellancy.
Formaldehyde, vulkacit H and formaldehyde/urea condensed products can add the improving agent as crushing strength, can be used for reducing caking trend and gather (vinyl-acetic ester)/surfactant mixtures (referring to US 4812158).Yet, must add these a large amount of relatively additives, otherwise their toxicity intractable.And, the appearance of surface active agent composition, as in poly-(vinyl-acetic ester)/surfactant mixtures, can when urea is used for industrial application such as production of resins, cause more substantial foam to form, and formaldehyde derivatives is unaccommodated under the situation of Melamine Production.
Also there is important difference with respect to the method for adding additive.Formaldehyde derivatives and this inventive composition are mixed with urea melt.Yet polyvinyl acetate/surfactant is to be ejected on the particle that is prefabricated into.
GB-A-1217106 has disclosed with high-molecular weight poly-(vinyl alcohol) as preventing that the additive that lumps from reducing the method for urea from caking.More particularly, according to this method, the aqueous solution of additive is mixed with aqueous solution of urea.Preferably, mix 0.005% to 5%b.w. additive based on weight of urea.According to giving embodiment, the starting point concentration of aqueous solution of urea is 80%; Behind the aqueous solution of mixed additive, at elevated temperatures, concentration becomes 95%, after this, makes urea crystals by cooling.Practice is known, contains polyvinyl alcohol in the urea and can cause dust to form, and may be because the mobile of internal moisture caused.
WO 02/20471 has mentioned a kind of method, and wherein the mixture with polyvinyl compound and inorganic salt mixes with urea melt.Confirmation is compared with untreated urea and has been improved gained particulate crushing strength and shock resistance.In addition, the compressibility that also proves urea has also reduced significantly.A kind of observation in this back can be a kind of advantage, because urea granules can be more not yielding when storing.Yet, in urea, add inorganic salt, as Tai-Ace S 150, the pH intensive reduces in the time of can making urea be dissolved in the water.This is a very big shortcoming when this urea technology that is used in is used as made resin.
US 4063919 has disclosed a kind of Ru 2006101161 that contains polyvinyl alcohol polymer and be used for the softening agent of polyvinyl alcohol, and wherein this softening agent is preferably selected from glycerine, Sorbitol Powder, ethylene glycol, has polyoxyethylene glycol of 4-20 C atom and composition thereof.In addition, mannitol and sucrose are also mentioned as softening agent in the disclosure thing.Though Sorbitol Powder, mannitol and sucrose are carbohydrates, they are known as polyoxyethylene glycol in the disclosure thing.Shortcoming is that carbohydrate can be in high temperature (＞100 ℃) variable color down, promptly so-called caramelize.Equally, the existence of little polar compound can make urea that higher water absorbability is arranged, and therefore recrystallize can take place, thereby dust forms and will sharply increase.
US 5766302 has mentioned the composition of fertilizer such as urea, polyvinyl alcohol and sulfomethylated lignin acid alkali metal salt.But sulfonated lignin can bring brown to urea, and this is that the technician is known.This is undesired during a lot of urea are used, as in the preparation of trimeric cyanamide.Therefore in composition of the present invention, do not contain sulfonated lignin; On the other hand, composition of the present invention does not fade, this because of as imagination, therefore they are inert to urea and/or thermolysis, do not have any color reaction.
Goal of the invention
Therefore, an object of the present invention is to provide a kind of urea composition, it has low compressibility, low knot certainly trend and low moisture susceptibility, overcomes above-mentioned shortcoming thus.
Detailed Description Of The Invention
The applicant is surprised to find, and at least two kinds of different polymkeric substance are added in the urea melt, and at least a in the described polymkeric substance is the polyalkenyl compound, and the result obviously reduces the compressibility and the caking trend of the urea granules that after this forms.And urea granules is insensitive to the recrystallize that is produced by moisture absorption in storage and the treating processes.No matter as aqueous mixture or solution, polymkeric substance can be added to separately in the fusing urea, also can add with the polyalkenyl compound.According to embodiment preferred, total add-on of polymeric blends is the 10%b.w. of urea total amount to the maximum.Present use relates to first polymkeric substance of urea, polyalkenyl compound form, with the intimate mixture of second polymkeric substance of hydroxyl, carboxylic acid, amine and/or amide group, it is much lower that the dust that makes caking trend, compressibility and composition recrystallize cause forms the urea of handling than untreated urea and form known.Preferably, first polymkeric substance is the polyalkenyl compound particularly, as polyalkenyl amines, and preferably polyethylene amine, polyvinyl formamide or PAH, and second polymkeric substance preferably polyethylene alcohol or the poly aspartic acid.
New additive according to the present invention is preferably the mixture of nitrogenous polyalkenyl compound, and the general formula of this polyalkenyl compound is (C-CX)
n(C-CY)
m, n=2-2 wherein, 000,000, m=0-2,000,000, wherein X and Y are NH independently of one another
2, (CH
2)
nNH
2, NH
2.HCl, (CH
2)
nNHR, (CH
2)
nNH
2.HCl, NH-HC=O, the part in the group that NH-RC=O forms, Y can further be H, wherein R is made up of the alkyl or alkenyl with 1-30 C atom, n=1-5.These polymkeric substance preferably mix with poly aspartic acid or polyvinyl compound, and the general formula of polyvinyl compound is (CHX-CHY)
n, wherein n is 4-10,000 integer, and X and Y are independently from each other hydrogen atom, carboxylic acid group, ester group, hydroxyl, amido and amide group, preferably polyethylene alcohol.
Dosage different, Biodegradable polymeric is the 50-10 based on weight of urea, 000ppm, and preferred 500-3,000ppm, wherein, preferably water is used as solvent.The temperature of handling is generally 10-160 ℃, is preferably 80-140 ℃.
Preferred embodiment is reflected in the dependent claims (subclaims).
In WO 02/20471 applicant claimed be used for urea based on polyvinyl compound (CHX-CHY)
nPelletizing additives.
Having put down in writing poly aspartic acid in PCT publication WO 02/20471 does not significantly improve the hardness of urea.
In surprise, the mixing of at least two kinds of particular polymers of the present discovery of applicant has synergy to the physicals of urea.
And it is significant adding poly aspartic acid in urea, because this biological polymer can increase the productivity (referring to US 5861356) of plant.
The advantage of polyvinyl alcohol, polyalkenyl amines and poly aspartic acid be favorable biological degradability energy, relative low toxicity and with the good miscibility of water.Use the additive of these products as carbamide granulation, than the present circumstances that produces poisonous formaldehyde products, much lower to the pressure that environment brings.
Therefore the present invention relates to as urea composition defined in the appended claims, compare with the urea composition of routine, said composition has the dust that compressibility, caking trend and the recrystallize of reduction cause and forms.
To the present invention be described with many embodiment and to the test of the quality of the urea granules that uses and form of producing representational method below.These embodiment only are used for illustrating but do not limit protection domain of the presently claimed invention.
The preparation method
The aqueous solution (having the concentration that embodiment provides) of additive is joined in the urea melt of being made up of 99.7%w/w urea p.a. and 0.3%w/w water.After this, respectively fusing urea is added drop-wise to by height and forms urea granules on the sheet glass at 1cm.After the curing, particle is scraped off from sheet glass, micronic dust is removed by the method for mesh screen.Collecting granules also is kept in the air impervious flask, up to measuring compressibility and caking trend.
Determine the method for compressibility and caking
Filling internal diameter with the 40g urea granules is the transparent pipe of 3cm.At its top plunger is installed, on sample, applies the pressure of about 600kPa.After having applied overvoltage at once and after 24 hours, measure the height of urea column.The height relative mistake, promptly the compressibility measuring result is calculated (Δ height (%)) by these two values.
Can determine the degree that knot is determined by the crushing strength of measuring the urea sample of compressing.
Determine the degree methods of the recrystallize that causes by moisture absorption
Filling diameter with the urea granules of 15.0g is the Petri dish of about 8.5cm.Then it is moved into relative air humidity and is 80%, temperature is 20 ℃ phytotron.After 24 hours, measuring the weight that is caused by the pellet moisture absorption increases, and after this Petri dish is closed with corresponding cap seal.This culture dish is at room temperature placed the dark place.After fortnight, by under magnifying glass, observing the content that particle is checked culture dish.
Abbreviation ghk representative does not have recrystallize, yet hk has represented at moisture absorption and dry back recrystallize.
Embodiment 1
Tested much with solution in the water or form of mixtures polymkeric substance as granulation additive for urea.Polymkeric substance is as shown in table 1.Table 2 has shown the result who obtains with the aqueous solution.
Table 1
| Active compound | Dissolved percentage ratio (w/w%) | Molecular weight (gram/mole) | Degree of hydrolysis (%) |
| Polyvinyl alcohol | 12 | ±15,000 | ＞80 |
| PAH | 10 | ±15,000 | - |
| PAH HCl salt | 50 | ±15,000 | - |
| PAH/diallyl amine multipolymer | 40 | ±70,000 | - |
| Polyvinylamine 1 | 45 | ±10,000 | ＞90 |
| Polyvinylamine 2 | 36 | ±45,000 | ＞90 |
| Polyvinylamine 3 | 30 | ±340,000 | ＞90 |
| Polyvinyl formamide | 22 | ±340,000 | 30 |
| Poly aspartic acid | 40 | ±2,500 | - |
Table 2
| Raw material | Dosage (ppm) | Compressibility (%) | Caking trend (N) | Suction back outward appearance |
| Blank | 0 | 10 | 9.0 | ghk |
| Urea-formaldehyde (80%) | 3000 | 2 | 0.7 | ghk |
| Polyvinyl alcohol (aq) | 1000 | 5 | 3.8 | hk |
| PAH | 1000 | 3 | 5.7 | hk |
| PAH HCl salt | 1000 | 5 | 4.3 | hk |
| PAH/diallyl amine multipolymer | 1000 | 4 | 3.9 | hk |
| Polyvinylamine 1 | 1000 | 5 | 0.8 | ghk |
| Polyvinylamine 2 | 1000 | 7 | 3.9 | ghk |
| Polyvinylamine 3 | 1000 | 5 | 3.1 | ghk |
| Polyvinyl formamide | 1000 | 5 | 7.0 | ghk |
| Poly aspartic acid | 1000 | 11 | 8.5 | ghk |
Can obtain as drawing a conclusion from last table: nearly all tested polymkeric substance all has active influence to the reduction of compressibility and caking.Also exist chemical compound lot after moisture absorption, can eliminate the recrystallize of urea granules.But tested compounds can not be near the quality of the urea granules of using urea-formaldehyde treated.
Embodiment 2
Subsequently, serve as that several mixtures are formed on the basis with polyvinyl alcohol and polyvinylamine/polyvinyl formamide.From the polyvinyl alcohol solution of 12w/w% (＞80% hydrolysis, molar mass is about 15,000g/mol) beginning is to wherein adding 5.0w/w% polymer with nitrogen (concentration is referring to table 1).The result is as shown in table 3.
Table 3
| Polymkeric substance | Dosage (ppm) | Compressibility (%) | Caking trend (N) | Suction back outward appearance |
| Polyvinylamine 1 | 1000 | 2 | 0 | hk |
| Polyvinylamine 2 | 1000 | 2 | 0.1 | hk |
| Polyvinylamine 3 | 1000 | 3 | 0.5 | ghk |
| Polyvinyl formamide | 1000 | 2 | 0.5 | hk |
| PAH | 1000 | 3 | 0.7 | hk |
Can reach a conclusion from the result: synergy is arranged, this nitrogenous compound such as polyvinylamine, polyvinyl formamide and PAH to preparing high-quality urea granules between polyvinyl alcohol and the polymer with nitrogen.The use of the mixture of polyvinyl alcohol and High molecular weight polyethylene amine makes urea insensitive to recrystallize after moisture absorption extraly.
Embodiment 3
Because may there be favorable influence in poly aspartic acid to the growth of plant, therefore tested much mixture based on 80%w/w poly aspartic acid (40%w/w activity) and 20%w/w polyvinylamine, polyvinyl formamide or polyvinyl alcohol (concentration is referring to table 1).The result is as shown in table 4.
Table 4
| Polymkeric substance | Total mixture dosage (ppm) | Compressibility (%) | Caking trend (N) | Suction back outward appearance |
| Polyvinylamine 1 | 1000 | 3 | 0.2 | ghk |
| Polyvinylamine 2 | 1000 | 2 | 0.3 | ghk |
| Polyvinylamine 3 | 1000 | 2 | 0.6 | ghk |
| Polyvinyl formamide | 1000 | 3 | 0.8 | ghk |
| PAH | 1000 | 2 | 0.3 | ghk |
| Polyvinyl alcohol * | 1000 | 3 | 0.9 | hk |
*Poly aspartic acid and polyvinyl alcohol are prepared respectively
Above-mentioned test has shown based on the additive of poly aspartic acid and polarity polyalkenyl compound gives urea granules fabulous physicals.
Embodiment 4
Also test and added three kinds of different polymkeric substance to urea melt and whether the particulate character of gained is had positive effect.For this is test, begin from the mixture of the polyvinyl alcohol of 80%w/w (12%w/w activity,＞80% hydrolysis) and 20%w/w polyvinylamine 1 (45%w/w activity,＞90% hydrolysis).This mixture is joined in the urea melt, and dosage is 700ppm.Then, the another kind of polymkeric substance of mentioning in the table 5 of preparation 300ppm (concentration is referring to table 1).The result is as shown in table 5.
Table 5
| Polymkeric substance | Compressibility (%) | Caking trend (N) | Suction back outward appearance |
| Polyvinyl formamide | 2 | 0.2 | ghk |
| PAH | 2 | 0.2 | ghk |
| Poly aspartic acid | 1 | 0 | ghk |
Use as three kinds of mixture of polymers of the additive in the urea granules production has brought high-quality urea granules.
Claims (12)
1, a kind of urea composition that do not fade is made up of urea mixture different with at least two kinds, Biodegradable polymeric, and at least a in the wherein said polymkeric substance is the polyalkenyl compound.
2, urea composition according to claim 1, wherein the polyalkenyl compound is nitrogenous, preferred polyalkenyl amines.
3, urea polymer according to claim 1 and 2, wherein the thiazolinyl of polyalkenyl amines contains 1-6 carbon atom, preferred 2-4 carbon atom.
4, according to the described urea composition of claim 1 to 3, wherein the general formula of polyalkenyl amines is (C-CX)
n(C-CY)
m, wherein
N=2 to 2,000,000, m=0 to 2,000,000,
X＝NH
2，CH
2NH
2，NH-HC＝O，NH-RC＝O，CH
2NHR，
Y＝H，NH
2，CH
2NH
2，NH-HC＝O，NH-RC＝O，CH
2NHR，
R=has the alkyl or alkenyl of 1-30 carbon atom.
5, urea composition according to claim 4, m=0 wherein, n=2 to 2,000,000, preferred n=100 to 20,000.
6, according to the one or more described urea composition of claim 1 to 5, wherein polyalkenyl amines is selected from polyvinylamine, polyvinyl formamide, PAH, preferably polyethylene amine or PAH.
7, according to the one or more described urea composition of claim 1 to 6, wherein the general formula of second polymkeric substance is (CHX-CHY)
n, wherein n is 4 to 10,000 integer, X and Y are independently from each other hydrogen atom, carboxylic acid group, ester group, hydroxyl, amido or amide group.
8, according to the one or more described urea composition of claim 1 to 6, wherein second polymkeric substance is made up of polyvinyl alcohol, its hydrolysis degree 〉=70%, preferred 〉=80%.
9, according to the one or more described urea composition of claim 1 to 7, wherein second polymkeric substance is a poly aspartic acid.
10, a kind of preparation is according to the method for the one or more described urea composition that do not fade of claim 1 to 9, wherein at least two kinds of solution different, biodegradable polymkeric substance are mixed with urea, add-on is the 50-10 based on weight of urea, 000ppm, preferred 500-3,000ppm is then according to known method itself, remove and desolvate, thereby obtain described urea composition.
11, method according to claim 10, wherein solvent is a polar solvent, preferably water.
12, according to claim 10 and 11 described methods, wherein this method is 10-160 ℃ in temperature, carries out under preferred 80-140 ℃.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL1028019A NL1028019C2 (en) | 2005-01-14 | 2005-01-14 | Free-flowing, mineral oil-free granulate particles of plant auxiliary agent comprises reaction product of plant auxiliary agent containing nitrogen, phosphorus and/or potassium and waste flow of natural material containing nitrogen compound |
| NL1028019 | 2005-01-14 | ||
| NL1028198 | 2005-02-04 | ||
| NL1028198A NL1028198C2 (en) | 2005-02-04 | 2005-02-04 | Free-flowing, mineral oil-free granulate particles of plant auxiliary agent comprises reaction product of plant auxiliary agent containing nitrogen, phosphorus and/or potassium and waste flow of natural material containing nitrogen compound |
| PCT/NL2006/000023 WO2006091077A1 (en) | 2005-01-14 | 2006-01-16 | Urea composition having reduced compressibility, caking and dust formation, and process for its preparation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101102980A true CN101102980A (en) | 2008-01-09 |
| CN101102980B CN101102980B (en) | 2013-06-19 |
Family
ID=34974855
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200680002294.5A Active CN101102980B (en) | 2005-01-14 | 2006-01-16 | Urea composition having reduced compressibility, caking and dust formation, and process for its preparation |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN101102980B (en) |
| NL (1) | NL1028019C2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102079676A (en) * | 2010-11-30 | 2011-06-01 | 大连化工研究设计院 | Ammonium chloride anti-blocking agent composition and application |
| CN106458782A (en) * | 2014-06-20 | 2017-02-22 | 伍德肥料技术公司 | Urea composition and method for producing same |
| CN108610189A (en) * | 2018-08-02 | 2018-10-02 | 中国石油大学(北京) | A kind of inclusion compound type slow-release carbamide fertilizer and preparation method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU537991A1 (en) * | 1975-03-07 | 1976-12-05 | Предприятие П/Я Р-6603 | Method of elimination of ammonia nitrate caking |
| WO1994026680A1 (en) * | 1993-05-07 | 1994-11-24 | The University Of New England | Improved fertilizer coating process |
| JPH08277191A (en) * | 1995-04-06 | 1996-10-22 | Mitsubishi Chem Corp | Slow-release granular rertilizer and its production |
| DE19820297A1 (en) * | 1997-05-28 | 1998-12-03 | Basf Ag | Encapsulated slow release agricultural fertiliser |
| DE19753297A1 (en) * | 1997-12-01 | 1999-06-02 | Basf Ag | Process for the preparation of solid dosage forms |
| AU2001264706A1 (en) * | 2000-05-19 | 2001-12-03 | Battelle Memorial Institute | Controlled release of materials from polymer matrices |
-
2005
- 2005-01-14 NL NL1028019A patent/NL1028019C2/en not_active IP Right Cessation
-
2006
- 2006-01-16 CN CN200680002294.5A patent/CN101102980B/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102079676A (en) * | 2010-11-30 | 2011-06-01 | 大连化工研究设计院 | Ammonium chloride anti-blocking agent composition and application |
| CN102079676B (en) * | 2010-11-30 | 2013-10-16 | 大连化工研究设计院 | Ammonium chloride anti-blocking agent composition and application |
| CN106458782A (en) * | 2014-06-20 | 2017-02-22 | 伍德肥料技术公司 | Urea composition and method for producing same |
| CN108610189A (en) * | 2018-08-02 | 2018-10-02 | 中国石油大学(北京) | A kind of inclusion compound type slow-release carbamide fertilizer and preparation method thereof |
| CN108610189B (en) * | 2018-08-02 | 2021-06-22 | 中国石油大学(北京) | Clathrate compound type slow-release urea fertilizer and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101102980B (en) | 2013-06-19 |
| NL1028019C2 (en) | 2006-07-17 |
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