CN1034657C - Slowly-releasing coated fertilizer and production thereof - Google Patents
Slowly-releasing coated fertilizer and production thereof Download PDFInfo
- Publication number
- CN1034657C CN1034657C CN93100227A CN93100227A CN1034657C CN 1034657 C CN1034657 C CN 1034657C CN 93100227 A CN93100227 A CN 93100227A CN 93100227 A CN93100227 A CN 93100227A CN 1034657 C CN1034657 C CN 1034657C
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- CN
- China
- Prior art keywords
- urea
- weight
- blend thing
- filling
- slow release
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/30—Layered or coated, e.g. dust-preventing coatings
- C05G5/37—Layered or coated, e.g. dust-preventing coatings layered or coated with a polymer
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- Life Sciences & Earth Sciences (AREA)
- Pest Control & Pesticides (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Fertilizers (AREA)
Abstract
The present invention relates to an envelope slow release fertilizer and a preparation method thereof. The envelope filling blending substances comprise inorganic or organic substance powder with adsorbability, and water soluble substances are absorbed in the powder. Because of the adsorbability of the filling blending substances, high molecular polymers and filling substances are close combined without pore space; after fertilization, the water soluble substances in the envelope are dissolved, even release pores are formed on the envelopes, and the envelopes can crack into the powder which is smaller than 200 meshes after the release of the fertilizers. Before fertilization, the present invention has strong damage resisting ability; in fertilization, the present invention can evenly open the release pores; the present invention is very suitable for the fertilization of rice fields because of the exact and flexible regulation of release speed.
Description
The present invention relates to contain in a kind of coating the superpolymer coated slow release fertilizer and the method for making thereof of filling blend thing.
Granulated fertilizer with pure polymer film cladding can delay the dissolution rate of fertilizer nutrient, and has anti-preferably damage capability.But it discharges nutrient speed and difficult cooperation of the time of the required nutrient of plant-growth, as release rate equilibrium etc. inadequately.In addition, its coated fertilizer remnant decomposition course is slow, and plant growth is had certain disadvantageous effect.
English Patent (GB2011367A) discloses a kind of coated particle fertilizer and production method thereof, it is to coat the film of being made up of polyolefine, ethene one vinyl acetate copolymer or inferior vinyl resins on the granulated fertilizer surface, and is filled with the fine dust of inorganic matter between 0.01 μ to 40 μ in the coating.Fine powder and resin can not closely stick together mutually, have formed hole.Like this, the quantity that the control fine powder adds can be made the coating perforate artificially, thereby regulates the release rate of fertilizer nutrient, but this adjusting is more coarse, and it makes coating intensity that obvious downward trend be arranged.This fertilizer is made in fluidized-bed, and it requires resin to have certain special property, and promptly its solution forms solution when heating.And when cooling forms gel.This requirement has limited the kind of usable resins.Such as, polystyrene resin does not just possess above-mentioned character, thereby can not adopt.
The objective of the invention is to seek a kind of filled-type coated slow release fertilizer and method for making thereof, the adding of its weighting material does not reduce coating intensity, and after using, can more accurately open the nutrient release aperture on the coating.After fertile core discharged, coating became powder in farming.Aspect manufacturing cost, seek a kind of ratio of performance to price than higher scheme.
Main points of the present invention are: prepare a kind of coated slow release fertilizer, forms by composite fertilizer's fuse and the superpolymer coating that contains the filling blend thing, it is characterized in that containing in the filling blend thing of coating and have the inorganic of adsorptivity or organic substance powder and be adsorbed with the water-soluble material of energy therein.
Because the adsorptivity of weighting material makes superpolymer can more closely combine with weighting material, the crack of not boxing out has guaranteed coating intensity.This adsorbability material is in advance in the certain density aqueous solution simultaneously, adsorb a certain amount of water-soluble substances according to the adsorption equilibrium principle, after fertilizer is used, because the effect of moisture content, the water-soluble substances desorption on adsorbent top layer dissolving in the coating, thereby form the more stable hole of size in coating, nutrient is balanced to be discharged thereby can make.As seen, this perforate principle, the regulatory function of coating can realize by the adsorption equilibrium curve controlled by the kind of selection adsorbability material and these three factors of concentration of loading level and obtain solution.Usually, the adsorptivity of adsorbability material is strong more, adding (filling) amount is many more, strength of solution is high more, and fertilizer nutrient release rate is just fast more after its film forming.Otherwise it is then slow more.
The composition of coating (parts by weight) comprises; 100 parts of superpolymer; Filling blend thing 5-600 part, wherein (1) to contain the inorganic or organic substance weight percent of the adsorptivity of water-soluble substances be 10-100%; (2) other weighting material weight percents are 0-90%.
Coating is formed (parts by weight) preferably: 100 parts of superpolymer; Filling blend thing 100-200 part, wherein (1) to contain the inorganic or organic substance weight percent of the adsorptivity of water-soluble substances be 70-100%; (2) other weighting material weight percents are 0-30%.
In the inorganic or organic substance of above-mentioned adsorptivity, the content of water-soluble substances is the content of adsorbability material when reaching adsorption equilibrium in water soluble substance solution.
The used superpolymer of the present invention is polystyrene, polyethylene, polypropylene, polyvinyl chloride.These superpolymer can use the industrial chemicals of " newly ", also can use the identical waste product of its main component.
Inorganic or the organic substance of the adsorptivity that the present invention selects for use is powders such as wilkinite, vermiculite power, carbon mud (industrial activited carbon waste residue), weathered coal, brown coal, humic acids.Since bentonitic high adsorption capacity, good dispersity, and huge at the occurring in nature reserves, so it is a kind of optimal adsorbability material.
Selected processing adsorptivity its solute of solution inorganic or organic substance of the present invention is that water-soluble substances has following a few class:
(1) inorganic salt are as MgSO
4, Na
2SO
4, KCl, NaNO
3Deng.
(2) organism is as urea and aminated compounds etc.;
(3) water soluble polymer is as urea-formaldehyde resin, polyvinyl alcohol, hydrolyzed starch etc.
Another characteristics of the present invention are, have also added other weighting materials in the coating, to improve surface strength and fragility, can make coating be easy to pulverize after can fertilizer discharges in film.The substance classes that can add is a lot, but from utilizing solid waste, the angle that further reduces cost is set out, and other weighting materials that the present invention selects have following a few class:
(1) comminuted plants organic waste materials as leaf, straw, cotton seed hull, grain of rice skin, peanut skin, offal skin etc., also can be used wood powder, starch;
(2) the animal organic waste materials of Fen Suiing as the waste tankage (comprising skin, hair, hoof, blood) in various animal bones, slaughterhouse, meat and the internal organ that anorexia is used, also can be used fish meal;
(3) powder of mineral materials is as wilkinite, weathered coal, fused(calcium magnesium)phosphate, flyash, lime carbonate etc.
The used compound manure fuse of the present invention is based on nitrogen, phosphorus, potash fertilizer, mixes some trace elements, humic acids, brown coal, agricultural chemicals, plant-growth regulator etc. and makes through granulation.Between the thickness of coating, perforate density, film and the fuse and part by weight and fuse size, can regulate according to the kind of crop and the needs of different growing stage.
Main implementation step of the present invention is as follows:
(1) earlier with the superpolymer oven dry, be dissolved in and make macromolecular solution in the coordinative solvent, its concentration is that the weight percent of superpolymer is 1-60%;
(2) the organic or inorganic material powder that has adsorptivity in the filling blend thing that adds is carried out following processing; Earlier, pour into then in the solution that contains water-soluble substances and soak, and fully stir, grind its oven dry, treat its adsorption equilibrium after, leach dry for standby;
(3) in the macromolecular solution that (1) obtains, add treated organic or inorganic thing powder, add toughner, tensio-active agent, colorant and other filling blend things again by aforementioned ratio, with sand mill or colloidal mill with it levigate and mixing, make spray coating liquor;
(4) in rotary drum, above-mentioned spray coating liquor is sprayed on the compound fertilizer granule surface.Treat solvent be heated the volatilization after promptly make coated slow release fertilizer.
Slow release fertilizer release rate as method for preparing is too fast, it can also be increased to be coated with other component coatings that one or more layers accounts for the heavy 0.1-10% of fertilizer core.
Effect of the present invention:
Because the adsorptivity filling blend thing that contains in the coating of this coated slow release fertilizer can more closely combine with superpolymer, so anti-damage ability is strong before using, the intensity height.And after using, because the dissolving of water-soluble substances in the coating, perforate equably on the coating, nutrient is discharged evenly, and release rate is regulated better, accurately flexibly, particularly fertilizer has discharged in the film, water-filling in the film chamber, the fragility of putamina make it very easily pulverize in farming again, resolve into the following fine powder of 200 orders.
The present invention selects the rotary drum working method for use, can make fertilizer outward appearance slyness, no corner angle, coating densification hard, further improves the anti-energy side of decreasing.
This slow release fertilizer is used for waterborne kind of rice test, and per mu yield is increased, and the utilization ratio of dedicated fertilizer improves 10-15 percentage point, has the saving of labor and reduces the advantage of polluting.
Actual effect of the present invention can further obtain proof by embodiment and testing and analysis data thereof.
Embodiment 1:
One, raw material
1, be prepared into the particulate state that varies in size by weight 1.94: 2.12: 0.95 with urea, general calcium, Repone K, its weight at 0.18 gram/grain between the 1.5 gram/grains.
2, spray coating liquor preparation:
Getting waste old polystyrene foamed plastic and benzene mixed (mixture that comprises benzene,toluene,xylene) is 14: 100 preparation macromolecule polysterol solution at normal temperatures by weight.Get in the quantitative swelling concentration with 5 times of weight and be 0.2% MgSO
4Solution soaking 24 hours also is interrupted and is stirred, and leaches oven dry then.Per 5 milliliters of polystyrene solutions add the treated swelling of 1 gram ±, grind mixing and can make spray coating liquor.
Two, production method:
Add an amount of compound fertilizer granule in rotary drum, making the rotary drum rotating speed is 40 rev/mins, slowly adds spray coating liquor, adds talcum powder simultaneously.Treat after the solvent evaporates.
Make 5 kinds of samples, see Table 1.
Three, discharge P
2O
5Mensuration:
1, method; Get coat fertilizer grain 10 and restrain the container of packing into, add 200 milliliters of distilled water.During mensuration complete soln is poured out, measured its P
2O
5Content.Use the distilled water flushing particle, add 200 ml distilled waters again.And the like.At last particle is pulverized, measured residue P
2O
5Content.
2, test result sees Table 2.
Made slow release fertilizer contains P
2O
5% (water-soluble) average out to 3.90%, an average day burst size accounts for total amount 2.84%.P
2O
5Discharge 80% and on average need 28 days.The nutrient release rate relatively slowly, evenly.
Four, temperature is to the influence of nutrient dissolution rate:
1,3 kinds of different coated slow release fertilizers of thickness is respectively got 10 grams, be soaked in respectively in the container that fills 200 ml distilled waters, then in the dislocation baking oven.25 ℃ of following constant temperature 24 hours, measure the P that it discharges
2O
5Amount.
In addition above-mentioned 3 kinds of fertilizer are respectively got 10 grams, be soaked in respectively in the container that fills 200 ml distilled waters, placed 24 hours down in room temperature (average 14 ℃) then, measure the P that it discharges
2O
5Amount.
2, test result sees Table 3.
As can be seen from Table 3, temperature raises, and dissolution rate is accelerated.10 ℃ of the every risings of temperature, release rate approximately increase by 2 times (1.85 times of average out to).
Embodiment 2:
Get the waste vinylene chloride plastic goods, tetrahydrofuran (THF) is a solvent, be made into weight percent and be 6% solution, by weight wilkinite: polyvinyl chloride solution is to mix at 1: 3, in rotary drum, be sprayed on the fertile core, it is 10 millimeters that this fertilizer core contains urea 39%, general calcium 42%, Repone K 19%, diameter, promptly makes slow release fertilizer.Used wilkinite is 0.1% (NH with the mass percent of 5 times of weight
4)
2SO
4The solution soaking oven dry makes.
Table 1
| Sample number | Core grain kind | Core grain heavy (gram) | Spraying liquid measure (ml) | Add talcum powder (gram) | Core-skin than (%, wt) |
| 1 2 3 4 5 | The big grain of the big grain of grain granule in the big grain | 500 500 500 500 500 | 175 200 150 175 160 | 30 55 40 43 65 | 12 16 10 14 19 |
Table 2 controlled availability fertilizer discharges P
2O
5The mensuration of %
Table 3
| Sample number | 14℃ | 25℃ | Multiple |
| 1 2 3 | 0.103％ 0.169％ 0.356％ | 0.201％ 0.239％ 0.779％ | 1.95 1.41 2.19 |
Claims (4)
1, a kind of coated slow release fertilizer, it is made up of compound manure fuse and coating, it is characterized in that:
Described coating is made up of 100 weight part polystyrene, polyethylene, polypropylene or polyvinyl chloride superpolymer and 5-600 weight part filling blend thing basically, and filling blend thing described here (in filling blend thing weight) composed as follows: 10-100% adsorbs MgSO
4, Na
2SO
4, KCl, NaNO
3, urea, urea-formaldehyde resin, polyvinyl alcohol or amylatic wilkinite, vermiculite power, carbon mud, weathered coal, brown coal or humic acids powder; 0-90% comminuted plants waste material, animal waste and mineral substance.
2, coated slow release fertilizer according to claim 1 is characterized in that in filling blend thing weight, absorption MgSO
4, Na
2SO
4, KCl, NaNO
3, urea, urea-formaldehyde resin, polyvinyl alcohol or amylatic wilkinite, vermiculite power, carbon mud, weathered coal, brown coal or humic acids powder be 70-100%, comminuted plants waste material, animal waste, mineral substance are 0-30%.
3, coated slow release fertilizer according to claim 1 is characterized in that, described plant waste is leaf, straw, cotton seed hull, grain of rice skin, peanut skin, offal skin, wood powder or starch; Described animal waste is bone, skin, hair, hoof, blood, tankage or the fish meal of animal; Described mineral substance is fused(calcium magnesium)phosphate, flyash, lime carbonate.
4, aforesaid right requires the manufacture method of 1,2 or 3 described coated slow release fertilizers, and this method comprises that the following step poly-:
(1) with the superpolymer oven dry, is dissolved in the solvent, obtains the solution that superpolymer concentration is 1-60% (weight);
(2) with in the swelling, vermiculite power, carbon mud, weathered coal, brown coal or the oven dry of humic acids powder, add MgSO again
4, Na
2SO
4, KCl, NaNO
3, in urea, urea-formaldehyde resin, polyvinyl alcohol or the hydrolyzed starch solution, fully stir, grind, treat to leach oven dry after its adsorption equilibrium, mix with comminuted plants waste material, animal waste and mineral substance again, obtain the filling blend thing;
(3) above-mentioned filling blend thing is joined in the above-mentioned high polymeric solution, its high polymeric solution is 100 parts by its oven dry superpolymer parts by weight, then filling blend thing parts by weight are 5-600 part, the add-on of filling blend thing: in filling blend thing weight, and absorption MgSO
4, Na
2SO
4, KCl, NaNO
3, urea, urea-formaldehyde resin, polyvinyl alcohol or amylatic wilkinite, vermiculite power, carbon mud, weathered coal, brown coal or humic acids powder be 10-100%, plant waste, animal waste and mineral substance are 0-90%;
(4) add again in the above-mentioned high polymeric solution toughner, tensio-active agent, colorant, at last with sand mill or colloidal mill with whole materials levigate and mixing, make spray coating liquor;
(5) in rotary drum, above-mentioned spray coating liquor is sprayed on the compound fertilizer granule surface, treat solvent be heated the volatilization after promptly make coated slow release fertilizer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN93100227A CN1034657C (en) | 1993-01-14 | 1993-01-14 | Slowly-releasing coated fertilizer and production thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN93100227A CN1034657C (en) | 1993-01-14 | 1993-01-14 | Slowly-releasing coated fertilizer and production thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1074206A CN1074206A (en) | 1993-07-14 |
| CN1034657C true CN1034657C (en) | 1997-04-23 |
Family
ID=4982880
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN93100227A Expired - Fee Related CN1034657C (en) | 1993-01-14 | 1993-01-14 | Slowly-releasing coated fertilizer and production thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1034657C (en) |
Cited By (1)
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|---|---|---|---|---|
| US7794772B2 (en) | 2004-09-08 | 2010-09-14 | Takasago International Corporation | Concentrated coffee extract and process for producing the same |
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|---|---|---|---|---|
| US4019890A (en) * | 1973-12-28 | 1977-04-26 | Chissoasahi Fertilizer Co., Ltd. | Method for producing coated fertilizer |
| CN87105398A (en) * | 1986-07-07 | 1988-01-27 | 窒素公司 | Degradation property mulch film fertilizer |
| CN87105842A (en) * | 1986-08-05 | 1988-02-24 | 窒素公司 | Granulated fertilizer of band decomposable coating and preparation method thereof |
| EP0330331A1 (en) * | 1988-02-23 | 1989-08-30 | Chisso Corporation | Coated granular fertilizers |
-
1993
- 1993-01-14 CN CN93100227A patent/CN1034657C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4019890A (en) * | 1973-12-28 | 1977-04-26 | Chissoasahi Fertilizer Co., Ltd. | Method for producing coated fertilizer |
| CN87105398A (en) * | 1986-07-07 | 1988-01-27 | 窒素公司 | Degradation property mulch film fertilizer |
| CN87105842A (en) * | 1986-08-05 | 1988-02-24 | 窒素公司 | Granulated fertilizer of band decomposable coating and preparation method thereof |
| EP0330331A1 (en) * | 1988-02-23 | 1989-08-30 | Chisso Corporation | Coated granular fertilizers |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7794772B2 (en) | 2004-09-08 | 2010-09-14 | Takasago International Corporation | Concentrated coffee extract and process for producing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1074206A (en) | 1993-07-14 |
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