CN1880286A - Complex fertilizer production method without drying process - Google Patents
Complex fertilizer production method without drying process Download PDFInfo
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- CN1880286A CN1880286A CN 200510026732 CN200510026732A CN1880286A CN 1880286 A CN1880286 A CN 1880286A CN 200510026732 CN200510026732 CN 200510026732 CN 200510026732 A CN200510026732 A CN 200510026732A CN 1880286 A CN1880286 A CN 1880286A
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Abstract
This invention relates to a method for producing compound fertilizer without drying process, comprising: mix solid urea or urea solution with formaldehyde solution with heat to form mixed slurry, wherein the mole ratio of urea and formaldehyde is 5-9:1, the temperature of the slurry is 90-100Deg C; introduce the phosphate fertilizer which has been pre-heated to 60-90Deg C and solid material selected from one of nitrogen fertilizer, potassium fertilizer or solid filler, or the mixture thereof to the granulating apparatus; spray the mixed slurry on the solid material for granulating so as to produce the granular compound fertilizer. This invention utilizes reaction heat to achieve fertilizer self-drying, removes the drying system, saves energy consumption, and decreases the production cost. Besides, this invention has a high granulating rate and can decrease fertilizer agglomeration. The produced fertilizer is a slow-releasing fertilizer, which can improve the fertilizer utilization ratio.
Description
Technical field
The present invention relates to a kind of production method of composite fertilizer, specifically, relate to a kind of production method of having got rid of the particulate state composite fertilizer of drying process.
Background technology
Solid material production is adopted in the production of existing composite fertilizer mostly; the base fertilizer raw material that will contain nitrogen phosphorus potassium exactly is after mixing; send into the rotary drum granulator granulation, the material after the granulation is directly delivered to drying kiln for drying, promptly gets qualified product through the exsiccant material through cooling, screening.This production technology has the advantage that production process is simple, operation is easy to grasp.But, this method is owing to required moisture height when the material granulating, make that follow-up drying process duty ratio is bigger, the dust escaped quantity is big, production environment is bad, physical and mental health to operator has certain influence, and because prilling temperature is low, this method is unsuitable for the production of the composite fertilizer of nitrogen content height (as containing more than the N20%).
Chinese patent CN1307550A discloses a kind of production method of compound fertilizer granule, though this method has been saved the granulation after drying flow process in the traditional method, but raw material is introduced hot air temperature up to 200～300 ℃ during granulation, and the melt temperature of solid urea is 135 ℃, under so high prilling temperature, residence time of material is long slightly, and the growing amount of biuret will significantly increase, and biuret can cause the injury of farm crop when fertilizer is used.
Chinese patent CN1138728C discloses the method that a kind of two step method is produced urea-formaldehyde compound fertilizer, this method is with urea and concentrated formaldehyde solution reaction, add sulphuric acid soln again and reconcile pH to 4, drying is the fertile white solid of urea aldehyde, and then makes composite fertilizer with other solid n p k fertilizer mixing granulation.This production method flow process is long, and technological process be provided with unreasonablely, when the preparation of the first step urea aldehyde fertilizer, passed through processes such as heating, cooling, oven dry, make heat-energy losses very big, increased the fertiliser production cost, economic benefit is not obvious.
Summary of the invention
The purpose of this invention is to provide a kind of complex fertilizer production method that does not have drying process, this method is the reaction heat that generates when utilizing urea and formaldehyde reaction, and self-desiccation behind the material granulating obtains the particulate state composite fertilizer.
Principle of the present invention is: urea and formaldehyde can generate methylolurea under the certain temperature condition, and further, methylolurea condensation under acidic conditions generates a methylene urea.Condensation reaction is thermopositive reaction, and every Molar Energy is emitted 8 kilocalories heat, utilizes the heat release of this reaction can reach the self-desiccation purpose of fertilizer.Simultaneously,, both reduced the probability that biuret generates, made product can keep the fertilizer efficiency of long period again again because condensation reaction has taken place for part urea and formaldehyde.
The present invention realizes like this.A kind of complex fertilizer production method that does not have drying process of the present invention may further comprise the steps:
(1) solid urea or urea soln mix the formation mixed slurry with the formaldehyde solution heating, and the mol ratio of described urea and formaldehyde is 5～9: 1, and the temperature of mixed slurry is 90～100 ℃,
(2) introduce prilling granulator after the solid materials preheating, described solid materials is one or more the mixture in phosphate fertilizer and nitrogenous fertilizer, potash fertilizer or the solid filler, and the preheating temperature of solid materials is 60～90 ℃,
(3) mixed slurry is sprayed at granulation on the interior solid materials of prilling granulator, promptly makes granular complex fertilizer.
Used urea can be solid urea in the bright method of we, also can be the intermediates urea soln in the urea plant production process, the concentration of urea soln is necessary 〉=and 95 weight %.Used formaldehyde solution is that concentration is the concentrated formaldehyde solution of 30～50 weight %.The mol ratio of described urea and formaldehyde is 5～9: 1, and preferred mol ratio is 6～8: 1.The temperature of described mixed slurry is 90～100 ℃, and preferred temperature is 70～80 ℃.
In the method for the present invention, during granulation, the add-on that is sprayed at the mixed slurry on the solid materials accounts for 10～50 weight % of total weight of material, and preferred add-on is 30～40 weight %.
The solid materials that adds need carry out thermal pretreatment, and the preheating temperature of solid materials is 60～90 ℃, preferred 70～80 ℃.Solid materials with larger particles degree also needs to carry out break process before adding, the granularity of solid materials should be less than 2mm, preferably less than 1mm.
In the method for the present invention, described solid materials nitrogenous fertilizer is urea, ammonium nitrate, ammonium chloride or ammonium sulfate, phosphate fertilizer is normal superphosphate, double superhosphate, monoammonium phosphate or diammonium phosphate, potash fertilizer is Repone K or vitriolate of tartar, and solid filler is kaolin, terra alba, clay, wilkinite, ground dolomite, Paris white or calcite in powder.
In the method for the present invention, when adding solid materials, also can add the granulation together of secondary nutrients and trace element fertilizer, described secondary nutrients is the compound that contains calcium, magnesium, sulphur, can be calcium sulfate, normal superphosphate, rhombspar, magnesiumcarbonate, trimagnesium phosphate etc., trace element fertilizer is the compound that contains boron, iron, zinc, copper, manganese, can be copper sulfate, zinc sulfate, manganous sulfate, ferrous sulfate, borax, boric acid etc.
The inventive method compared with prior art has the following advantages:
1. method of the present invention, utilize urea and formaldehyde reaction to generate methylolurea, methylolurea condensation reaction under acidic conditions, every Molar Energy is emitted 8 kilocalories heat, reach the purpose of granulation fertiliser granulates self-desiccation, got rid of all very high dehumidification system of investment and process cost, saved energy consumption, reduce the fertiliser production cost, reduced the dust exhaust gas discharging.
2. method granulation balling ratio height of the present invention, balling ratio can bring up to 95% on the basis of original traditional technology balling ratio 60%, significantly reduced the granulation returning charge.
3. method of the present invention generates urea aldehyde at urea and formaldehyde reaction, is a kind of slowly-releasing efficient compound fertilizer, make incorporation of fertilizerin the soil after, continue to discharge, satisfy the needs of plant growth, reduced nitrogen loss, improved utilization rate of fertilizer.
4. method of the present invention because urea and formaldehyde reaction are formerly, also reduced base fertilizer reactions such as urea and phosphorus ammonium, Repone K and has generated the possibility of double salt, thereby can reduce the caking of fertilizer.
Embodiment
In order to implement the present invention better, the present invention is further illustrated now to enumerate following embodiment, but embodiment is not a limitation of the present invention, and the per-cent among the embodiment all is weight percentage.
Embodiment 1:
Get 240 kilograms of solid ureas; 50 kilograms of the formaldehyde solutions of 40% concentration; mix and be heated to 100 ℃, the mixed slurry of formation by pump delivery in the biaxial granulation machine, with 250 kilograms in 340 kilograms of monoammonium phosphates, the Repone K, the terra alba (CaSO that are heated to 70 ℃ in advance
4) 160 kilograms, 2 kilograms of extruding of calcium sulfate granulating, the fertilizer material behind the granulating promptly obtains the particle NPK compound fertilizer of high density through overcooling, screening, and product contains N15.00%, P
2O
515.00%, K
2O15.00%.
Embodiment 2:
Get 400 kilograms of the urea solns of urea plant flash evaporator outlet; concentration is 99.7 weight %; with 60 kilograms; concentration is that 50% formaldehyde solution is at pipe-line blending; mixed slip is sprayed directly on the solid materials that is heated to 60 ℃ in the rotary drum granulator in advance; solid materials should be crushed to granularity in advance less than 2mm; solid materials comprises 200 kilograms of diammonium phosphate; 300 kilograms of vitriolate of tartar; 80 kilograms of Paris whites; 1 kilogram of the vitriol oil, 1.5 kilograms in zinc sulfate, the material after the granulation is through cooling; screening; promptly obtain the NPK compound fertilizer of high density, this composite fertilizer specification is N-P
2O
5-K
2O=22-9-15, this composite fertilizer can be used as fertilizer special for tobacco, and application effect is obvious.
Embodiment 3:
Get 200 kilograms of urea plant flash evaporator outlet urea solns; concentration is 95.0 weight %; with 40 kilograms, concentration be that 45% formaldehyde solution is at pipe-line blending; mixed slip is sprayed directly on the mixture of 3 kilograms of the monoammonium phosphate double centner that is heated to 70 ℃ in the granulating disc in advance, 400 kilograms of general calcium, 200 kilograms of vitriolate of tartar, rhombspar double centner and boraxs; solid materials should be crushed to granularity in advance less than 1mm; granulation; material after the granulation is through overcooling; screening; the particle NPK compound fertilizer of concentration in promptly obtaining, product specification is N-P
2O
5-K
2O=10-10-10.
Embodiment 4:
Get the solid urea double centner; add concentration and be 30 kilograms of 30% formaldehyde solutions; under 90 ℃, mix; the mixed slurry that forms by pump delivery in rotary drum granulator; directly be sprayed onto on the mixture that is heated to 2 kilograms in 300 kilograms of about 80 ℃ monoammonium phosphates, 200 kilograms in Repone K, 400 kilograms of clays and ferrous sulfate in advance; solid materials should be crushed to granularity in advance less than 2mm; material after the granulation is concentration particle NPK compound fertilizer in cooling, screening promptly obtain, and product specification is N-P
2O
5-K
2O=10-13-12.
Embodiment 5:
Get 370 kilograms of solid ureas; add concentration and be 50 kilograms of 45% formaldehyde solutions; under 90 ℃, mix; the mixed slurry that forms by pump delivery in rotary drum granulator; directly be sprayed onto on the mixture that is heated to 1 kilogram of 130 kilograms of about 80 ℃ double superhosphate, 200 kilograms in Repone K, 270 kilograms in sal epsom and manganous sulfate in advance; solid materials should be crushed to granularity in advance less than 2mm; material after the granulation promptly obtains the particle NPK compound fertilizer through cooling, screening, and product specification is N-P
2O
5-K
2O=17-6-12.
Embodiment 6:
Get 420 kilograms of solid ureas; add concentration and be 50 kilograms of 50% formaldehyde solutions; under 100 ℃, mix; the mixed slurry that forms by pump delivery in rotary drum granulator; directly be sprayed onto on the mixture that is heated to 60 kilograms of 200 kilograms of about 90 ℃ normal superphosphates, 150 kilograms of diammonium phosphate, 170 kilograms in Repone K and kaolin in advance; solid materials should be crushed to granularity in advance less than 2mm; material after the granulation promptly obtains the particle NPK compound fertilizer through cooling, screening, and product specification is N-P
2O
5-K
2O=20-10-10.
Embodiment 7:
Get 235 kilograms of urea plant flash evaporator outlet urea solns; concentration is 93.0 weight %; add concentration and be 30 kilograms of 48% formaldehyde solutions; under 90 ℃, mix; the mixed slurry that forms by pump delivery in rotary drum granulator; directly be sprayed onto on the mixture that is heated to 410 kilograms of 220 kilograms of about 70 ℃ double superhosphate, vitriolate of tartar double centner and calcite in powder in advance, the material after the granulation promptly obtains the particle NPK compound fertilizer through cooling, screening, and product specification is N-P
2O
5-K
2O=10-10-5.
Embodiment 8:
Get 290 kilograms of urea plant flash evaporator outlet urea solns; concentration is 90.0 weight %; add concentration and be 50 kilograms of 30% formaldehyde solutions; under 90 ℃, mix; the mixed slurry that forms by pump delivery in rotary drum granulator; directly be sprayed onto on the mixture that is heated to 460 kilograms of 150 kilograms of about 80 ℃ double superhosphate, Repone K double centner and wilkinites in advance, the material after the granulation promptly obtains the particle NPK compound fertilizer through cooling, screening, and product specification is N-P
2O
5-K
2O=12-7-6.
Claims (9)
1, a kind of complex fertilizer production method that does not have drying process is characterized in that this production method may further comprise the steps:
(1) solid urea or urea soln mix the formation mixed slurry with the formaldehyde solution heating, and the mol ratio of described urea and formaldehyde is 5～9: 1, and the temperature of mixed slurry is 90～100 ℃,
(2) introduce prilling granulator after the solid materials preheating, described solid materials is one or more the mixture in phosphate fertilizer and nitrogenous fertilizer, potash fertilizer or the solid filler, and the preheating temperature of solid materials is 60～90 ℃,
(3) mixed slurry is sprayed at granulation on the interior solid materials of prilling granulator, promptly makes granular complex fertilizer.
2, the method for claim 1 is characterized in that: the mol ratio of described urea and formaldehyde is 6～8: 1.
3, the method for claim 1 is characterized in that: the temperature of described mixed slurry is 70～80 ℃.
4, the method for claim 1, it is characterized in that: the nitrogenous fertilizer in the described solid materials is urea, ammonium nitrate, ammonium chloride or ammonium sulfate, phosphate fertilizer is normal superphosphate, double superhosphate, monoammonium phosphate or diammonium phosphate, potash fertilizer is Repone K or vitriolate of tartar, and solid filler is kaolin, terra alba, clay, wilkinite, ground dolomite, Paris white or calcite in powder.
5, the method for claim 1 is characterized in that: the preheating temperature of described solid materials is 70～80 ℃.
6, the method for claim 1 is characterized in that: the granularity of described solid materials is less than 1mm.
7, the method for claim 1 is characterized in that: during granulation, the add-on of mixed slurry accounts for 10～50 weight % of total weight of material.
8, the method for claim 1 is characterized in that: during granulation, the add-on of mixed slurry accounts for 30～40 weight % of total weight of material.
9, the method for claim 1, it is characterized in that: when adding solid materials, also can add the granulation together of secondary nutrients and trace element fertilizer, described secondary nutrients is the compound that contains calcium, magnesium, sulphur, and trace element fertilizer is the compound that contains boron, iron, zinc, copper, manganese.
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| CN100410213C CN100410213C (en) | 2008-08-13 |
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| CN101857513A (en) * | 2010-05-13 | 2010-10-13 | 上海化工研究院 | Method for preparing long-acting slow-release compound fertilizers by one-step pulp spraying granulation |
| CN101891563A (en) * | 2010-06-17 | 2010-11-24 | 刘峰 | Slow/control release fertilizer produced by urease aminoacetic acid method |
| CN101913965A (en) * | 2010-07-23 | 2010-12-15 | 山东谷丰源化肥有限公司 | Urea formaldehyde sustained-release fertilizer and preparation method thereof |
| CN101475414B (en) * | 2008-11-20 | 2011-05-11 | 上海化工研究院 | Production method of tower type prilling slow release fertilizer |
| CN102491858A (en) * | 2011-12-20 | 2012-06-13 | 上海化工研究院 | Method for manufacturing urea-based nitrate slow-releasing compound fertilizer |
| CN102584494A (en) * | 2012-02-08 | 2012-07-18 | 福建师范大学 | Preparation method for in-situ coated controlled-release fertilizer urea slow-release particle fertilizer |
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| CN102910966A (en) * | 2011-08-05 | 2013-02-06 | 山东史贝美肥料开发有限公司 | Preparation method of special synergistic urea formaldehyde fertilizer for highland barley |
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| CN104671924A (en) * | 2014-01-14 | 2015-06-03 | 烟台海洲生物科技有限公司 | Process for manufacturing urea formaldehyde compound fertilizer |
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| CN1024274C (en) * | 1989-03-30 | 1994-04-20 | 王长山 | Compound fertilizer by spray granulating and preparation thereof |
| CN1048707C (en) * | 1997-03-07 | 2000-01-26 | 王长山 | Production process of composite urine fertilizer |
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| CN101993317B (en) * | 2009-08-12 | 2014-09-17 | 深圳市芭田生态工程股份有限公司 | Manufacturing method of puffed particle compound fertilizer and product thereof |
| CN101857513A (en) * | 2010-05-13 | 2010-10-13 | 上海化工研究院 | Method for preparing long-acting slow-release compound fertilizers by one-step pulp spraying granulation |
| CN101891563A (en) * | 2010-06-17 | 2010-11-24 | 刘峰 | Slow/control release fertilizer produced by urease aminoacetic acid method |
| CN101891563B (en) * | 2010-06-17 | 2013-01-30 | 刘峰 | Slow/control release fertilizer produced by urease aminoacetic acid method |
| CN101913965B (en) * | 2010-07-23 | 2013-05-08 | 山东谷丰源化肥有限公司 | Urea formaldehyde sustained-release fertilizer and preparation method thereof |
| CN101913965A (en) * | 2010-07-23 | 2010-12-15 | 山东谷丰源化肥有限公司 | Urea formaldehyde sustained-release fertilizer and preparation method thereof |
| CN102826882A (en) * | 2011-06-15 | 2012-12-19 | 山东史贝美肥料开发有限公司 | Carbamide chelated controlled release fertilizer and its preparation method |
| CN102826892A (en) * | 2011-06-18 | 2012-12-19 | 山东史贝美肥料开发有限公司 | Preparation method of special synergistic Arctium lappa L. sustained-release fertilizer |
| CN102910967A (en) * | 2011-08-05 | 2013-02-06 | 山东史贝美肥料开发有限公司 | Special urea formaldehyde efficacy-improved fertilizer for garlic and preparation method of fertilizer |
| CN102910966A (en) * | 2011-08-05 | 2013-02-06 | 山东史贝美肥料开发有限公司 | Preparation method of special synergistic urea formaldehyde fertilizer for highland barley |
| CN102491858A (en) * | 2011-12-20 | 2012-06-13 | 上海化工研究院 | Method for manufacturing urea-based nitrate slow-releasing compound fertilizer |
| CN102584494A (en) * | 2012-02-08 | 2012-07-18 | 福建师范大学 | Preparation method for in-situ coated controlled-release fertilizer urea slow-release particle fertilizer |
| CN103724091A (en) * | 2013-11-14 | 2014-04-16 | 大连创达技术交易市场有限公司 | Urea production technology |
| CN104671924A (en) * | 2014-01-14 | 2015-06-03 | 烟台海洲生物科技有限公司 | Process for manufacturing urea formaldehyde compound fertilizer |
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| CN106396928A (en) * | 2016-08-31 | 2017-02-15 | 贵州西洋实业有限公司 | Slow-release type compound fertilizer and production method thereof |
| CN114478129A (en) * | 2022-01-07 | 2022-05-13 | 中化农业（临沂）研发中心有限公司 | Extrusion granulation slow release fertilizer and preparation method thereof |
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