Background technology
The chemical fertilizer usage quantity is big, use is wide, has become one of most important production means in the agriculture prodn, in the agricultural industry cost, occupies than large portion.After chemical fertilizer water-soluble is manured into soil it, dissolving rapidly, decomposes, volatilization, run off, cause plant recovery of nutrient low, crop is incompatible to providing of nutrient to nutrient demand and chemical fertilizer; Not only cause the waste of resource, the raising of agricultural cost, the chemical fertilizer of loss threatens the environment structure that the mankind depend on for existence for the pollution of water body, atmosphere and edatope.Therefore, the controlled release of chemical fertilizer is the target that the insider pursues.
Control release composite fertilizer of the prior art adopts two kinds of forms mostly, and the technology of first filmcoated type utilizes sulfuration bed or rotary drum coating machine that controlled-release material is wrapping to the readily avaiable fertilizer particle surface.This product membrane wrapping thickness in process of production is difficult to control, causes fertilizer nutrient to discharge leading or hysteresis, has influenced the absorption of early stage or the middle and later periods of crop.It two is with powdery instantly-soluble nitrogenous fertilizer, phosphate fertilizer, potash fertilizer and can reduces the non-enveloped slow release fertilizer that its deliquescent material thorough mixing prepares; Common solid support material is that low water solubility nanometer consolidating material is evenly spread among powdery nitrogenous fertilizer, phosphate fertilizer, the potash fertilizer, changes the dissolution characteristics of fertilizer.Owing to be low water solubility nanometer consolidating material, fertilizer nutrient release to birth ratio resin and sulfur coating are very fast relatively, reach more than 120 day most, and the later stage that has influenced crop absorbs.Coated with resin, cost is high, and coated fertilizer is difficult to degraded, contaminate environment.
The problem that above-mentioned filmcoated type, non-enveloped slow release fertilizer exist is:
1. can not be according to the different steps of plant growth to nutrient demand, control fertilizer efficiency rate of release, can not for plant growth in good time, an amount of nutrient is provided.
2. the fertilizer nutrient utilization ratio is low.
3. effectively do not solve fertilizer nutrient loss, problem of environment pollution caused.
4. single, the poor compatibility of Technological adaptability that high tower pellatizer technology of the prior art exists, complex process, cost is higher.
5. coated fertilizer difficult degradation, contaminate environment.
6. price is high, is not suitable for field crop and uses.
Summary of the invention
The objective of the invention is to avoid above-mentioned weak point of the prior art; And provide a kind of can be according to the different steps of plant growth to nutrient demand, control fertilizer efficiency rate of release, for plant growth in good time, an amount of nutrient is provided; Utilization rate of fertilizer is high; Coated fertilizer is easy to degraded, helps environment protection, is applicable to the slow/controlled-release compound fertilizer of field crop.
The present invention also aims to provide a kind of employing fusion air-cooled granulation, Technological adaptability is strong, compatible good, save energy, and coating process is simple, the lower-cost preparation method of less investment.
The object of the invention can reach through following measure:
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention; It is characterized in that comprising two critical processes of melt pelletization and rotary drum coating, at first melt pelletization prepares built-in slow-release compound and mixed fertilizer particle, then; Make through different grain speed change, rotary drum coating again, raw materials used following with the preparation method:
A. raw material
Raw material is by weight percentage formed as follows:
Urea 35~65
Monoammonium phosphate or coarse whiting 9~36
Repone K or vitriolate of tartar 8~40
Granulation auxiliary material 1~38
The attapulgite 3~5 of nano-scale chitosan modification
Nano-scale chitosan coating agent 1~2
B. the preparation method comprises the steps:
Step 1. melt pelletization
A. urea melting, measure, feed intake
Pour granular urea into the urea rotary conveyor,, rise to the urea feed bin through chapelet; Get into the urea melting device through worm conveyor; Flow into the urine dashpot behind the urea melting, to cat head one-level tempering tank, the urea liquation that gets into the one-level tempering tank is 35~65 weight parts through the urine pump delivery.
B. other raw materials measure, feed intake
Monoammonium phosphate or coarse whiting, Repone K or vitriolate of tartar, powdery calcium powder or terra alba or Sodium sulfate anhydrous.min(99) or humic acid are poured rotary conveyor respectively into; Be promoted to feed bin separately through chapelet; Electronics metering weighing belt is established in the feed bin bottom; Measure monoammonium phosphate or coarse whiting 9~36 weight parts, Repone K or vitriolate of tartar 8~40 weight parts, calcium powder or terra alba or Sodium sulfate anhydrous.min(99) or humic acid 1~38 weight part respectively and go the powder heater heats, the material after the heating flow into the powder conveyor, simultaneously; Nano level modified attapulgite 3~5 weight parts are metered on the powder conveyor; Send into the cat head I and II tempering tank of granulating working procedure through bucket elevator, fully mixing is equipped with granulation and uses;
C. granulation
With the material of step b mixing, adopt tablets press to spray in the prilling tower, naturally cooling, curing promptly get built-in slow-release compound and mixed fertilizer particle;
Step 2. rotary drum coating
With built-in slow-release compound and mixed fertilizer particle 98~99 weight parts of step 1 preparation, be transported in the oven dry coating machine, utilize different grain transmission technology; With the agent of Nano chitosan coating; Regulate the sprinkling amount through SV,, evenly be sprayed onto the built-in slow-release compound and mixed fertilizer particle surface of 99~98 weight parts coating agent 1~2 weight part; Behind coating district rotary drum coating; Get into baking zone oven dry, cooler cooling immediately, metering, packing make particle diameter difference, the different slow/controlled-release compound fertilizer that is applicable to field crop of membrane wrapping thickness.
Of the present inventionly be applicable to that the slow/controlled-release compound fertilizer of field crop is a kind of novel slowly/controlled releasing fertilizer of high-efficiency environment friendly that is combined with the coated control release fertilizer technology and formed by the internally-arranged type slow-release fertilizer.Traditional internally-arranged type slow-release fertilizer claims that also nanostructure is fertile, be with fertilizer with can reduce the fertilizer that its deliquescent low water solubility nanometer consolidating material mixes.Low water solubility nanometer consolidating material-nano-scale chitosan that internally-arranged type slow-release fertilizer of the present invention is selected for use is attapulgite modified; It is a kind of environment-friendly type nano consolidating material; Selecting environmentally friendly natural polymer grid material-nano level attapulgite and bioabsorbable polymer material-chitosan for use is raw material, carries out physics and makes after composite modified with chemistry, and itself and nitrogen, phosphorus, potassium powder and urea melt carry out thorough mixing; Through IX and adsorption; Form the colloid reticulated structure, " net is caught " lived fertilizer nutrient, changed the dissolution characteristics of fertilizer.Compare with traditional internally-arranged type slow release fertilizer, slow release effect is significantly increased.
Chitosan has all been adopted in the attapulgite of feed composition nano-scale chitosan of the present invention modification and the agent of nano-scale chitosan coating, and chitosan is the product behind the chitin deacetylate, is the abundant natural organic matters of nature reserves.C in the cellulosic molecule
2On the position-OH base quilt-NH
2Base is exactly a chitosan after replacing.Chitosan is nonpoisonous and tasteless, biodegradable, is a kind of novel plant-growth regulator, and the storage that can improve chlorophyll content in the plant leaf, raising crop subtracts protein contnt, improves resistance against diseases, percentage of germination number of shoots and the seedling plant height of seed.In addition, chitosan is to the person poultry harmless, and wide material sources, degraded product can be used as the source of soil carbon and nitrogen.Feed composition therefore of the present invention adopts chitin modified attapulgite as sustained release dosage, and selects the agent of Nano chitosan coating for use.Made positive contribution for accomplishing task of the present invention.
Melting granulating technology of the present invention the temperature of molten mass self and brute force mixes and the high cut disperse emulsification effect under; Catch the low temperature eutectic that acts on the formation cancellated nano composite material of IPN molecule and have certain flowing property through IX, absorption, net; Adopt prilling tower sprinkling pelleting technology to carry out granulation then; When the spray tear drop falls to passing through the airflow of rising in prilling tower; By rapid crystallisation by cooling glomeration, form a kind of internally-arranged type slow-release compound and mixed fertilizer particle with quick-acting, middle effect function.
Coating process of the present invention is to drying in the coating machine with internally-arranged type slow-release compound and mixed fertilizer particle transport; Utilize different grain transmission technology,, regulate coating agent sprinkling amount through SV with the agent of Nano chitosan coating; The coating agent evenly is sprayed onto internally-arranged type slow-release compound and mixed fertilizer particle surface; Behind coating district rotary drum coating, get into baking zone oven dry and cooler cooling immediately, again through metering packing; Final production goes out the slow/controlled-release compound fertilizer that is applicable to field crop that the variable grain surface forms different membrane wrapping thicknesses, promptly has quick-acting, middle effect+long-acting function.
Attapulgite modified being produced by Anhui Province Diyuan Biotechnology CO.,Ltd of the nano-scale chitosan that the present invention adopts sold; Trade names are KS-3, and nano-scale chitosan is attapulgite modified to be a kind of additive that can control the fertilizer rate of release in the common fertilizer that makes an addition to, through natural materials is carried out physics and bio-modification; Act synergistically with complex material; Form huge interpenetrating(polymer)networks, " net is caught " lived chemical fertilizer nutrient, thereby reaches the raising chemical fertilizer utilization ratio; Reduce nutrient loss, reduce the purpose of environmental pollution.
The Nano chitosan coating agent that the present invention adopts; The trade names that are the production and sales of Binzhou prosperous imperial oilfield chemical ltd are the product of NMT-1; The agent of Nano chitosan coating is with the natural nano-mineral material and the bioabsorbable polymer material-polymer chitosan of the nutritive element that contains tens kinds of crop demands, a kind of environment-protection type coated material that forms through chemical industry microemulsified, the modification of high-shear technology.
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention is characterized in that said raw material composition by weight percentage as follows:
Urea 35~65
Monoammonium phosphate or coarse whiting 24~28
Repone K or vitriolate of tartar 22~24
Granulation auxiliary material 6~38
The attapulgite 3~5 of nano-scale chitosan modification
Nano-scale chitosan coating agent 1~2.
It is optimized technical scheme disclosed by the invention.
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention is characterized in that the granulation auxiliary material described in the A raw material is selected from any one in calcium powder, terra alba, Sodium sulfate anhydrous.min(99), the humic acid.
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention is characterized in that in the attapulgite of the nano-scale chitosan modification described in the A raw material weight content of chitosan >=3%th, optimized technical scheme.
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention is characterized in that in the nano-scale chitosan coating agent described in the A raw material weight content of chitosan >=5%.
Slow/controlled-release compound fertilizer that is applicable to field crop of the present invention and preparation method thereof is characterized in that said raw material composition by weight percentage as follows
Urea 38
Monoammonium phosphate 26
Repone K 13
Calcium powder 19
The attapulgite 3 of nano-scale chitosan modification
Nano-scale chitosan coating agent 1.
It is an optimized technical scheme.
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention is characterized in that said raw material composition by weight percentage as follows
Urea 40
Monoammonium phosphate 18
Repone K 20
Calcium powder 16.5
The attapulgite 4 of nano-scale chitosan modification
Nano-scale chitosan coating agent 1.5.
It is another optimized technical scheme.
The slow/controlled-release compound fertilizer that is applicable to field crop of the present invention is characterized in that said raw material composition by weight percentage as follows
Urea 50
Coarse whiting 27
Vitriolate of tartar 10
Humic acids 6.5
The attapulgite 5 of nano-scale chitosan modification
Nano-scale chitosan coating agent 1.5.
It also is an optimized technical scheme.
The present invention compares prior art has following positively effect:
1. provide a kind of can be according to the different steps of plant growth to nutrient demand, control fertilizer efficiency rate of release, for plant growth in good time, an amount of nutrient is provided; Utilization rate of fertilizer is high; Coated fertilizer is easy to degraded, helps environment protection, is applicable to the slow/controlled-release compound fertilizer of field crop.
2. provide a kind of employing fusion air-cooled granulation, Technological adaptability is strong, compatible good, save energy, and coating process is simple, less investment and lower-cost preparation method.
3.. composite fertilizer of the present invention can be according to the different steps of plant growth to nutrient demand, control fertilizer efficiency rate of release, for plant growth in good time, an amount of nutrient is provided.
2. the fertilizer nutrient utilization ratio is high, utilization rate of nitrogen fertilizer on paddy rice >=75%.On wheat >=65%.
3. efficiently solve fertilizer nutrient loss, problem of environment pollution caused.
4. high tower pellatizer production equipment of the prior art and technology are simply transformed promptly applicable to melting granulating technology requirement of the present invention.
5. coated fertilizer is easy to degraded, can be to water body, soil, air deleterious impact, and the protection environment.
6. starting material obtain easily, and production cost is low, and price is moderate, are suitable for field crop and use.
7. the production technique of the inventive method can improve the zero pour of melting liquid, makes product particle smooth, mellow and full, and outward appearance is shallow chlorine look, reduces the particle shrinkage cavity, reduces the ammonia loss.And the nutrient of this product is reasonable, moisture content is low, and prevented from caking is convenient to mechanized application.
8. composite fertilizer of the present invention can keep the nutrient longitudinal equilibrium, and control is run off.This product can be balanced nutritious in soil, accomplishes crop early stage, mid-term, later stage fertilizer deficiency not; Can be more by plant absorbing, the fertilizer nutrient of loss significantly reduces, and fertilizer nutrient more than needed remains in the soil, can supply following season plant to continue to absorb.Having changed common fertilizer supports part to discharge and too concentrates and resin coated controlled release fertilizer, sulfur coating controlled release fertilizer nutrient discharge shortcoming leading or that lag behind.
9. in soil, be prone to degraded, its degraded product gets in soil organic-inorganic compounding colloid, and long-term application can be improved soil physico-chemical characteristic, improves soil fertilizer and water retention capacity.
10. composite fertilizer of the present invention is suitable for using on the field crop, can be used as the disposable use of base manure, need not topdress in the centre, and the peasant saves time, laborsaving, saves the fertilizer input simultaneously.