CN103333033B

CN103333033B - The preparation method of low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer

Info

Publication number: CN103333033B
Application number: CN201310252232.1A
Authority: CN
Inventors: 邓跃全; 董发勤; 李娜; 李丽娟; 罗绍东; 邓智友
Original assignee: Southwest University of Science and Technology
Current assignee: Southwest University of Science and Technology
Priority date: 2013-06-24
Filing date: 2013-06-24
Publication date: 2015-08-05
Anticipated expiration: 2033-06-24
Also published as: CN103333033A

Abstract

The invention discloses a kind of preparation method of low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, it is characterized in that comprising: prepare ammonium sulfate masterbatch, preparation urea gypsum masterbatch, prepare wilkinite, prepare semi-hydrated gypsum, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite and prepare the steps such as low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.The present invention with low urea formaldehyde resin-composite gypsum material for sizing agent, composite with wilkinite again, form slow-releasing system, obtain low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer by extruding hybrid reaction, vibrosieve, disc granulation integration technology of preparing; Adopt the present invention, have that energy consumption is low, formaldehyde content is low and slowly-releasing nitrogen high, the slow release fertilizer of preparation significantly can increase the environmental pollution of grain yield, raising utilization rate of fertilizer, the initiation of reduction agricultural emissions, simultaneously for the comprehensive utilization of industrial gypsum provides effective way.

Description

The preparation method of low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer

Technical field

The invention belongs to fertilizer, relate to a kind of preparation method of low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.Low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer prepared by the present invention is suitable for and makes agrochemical, containing slow and quick-acting nitrogen composition; The present invention with multiple/mixed material of urea-formaldehyde resin-semi-hydrated gypsum for sizing agent, composite with wilkinite again, form slow-releasing system, by extruding hybrid reaction, vibrosieve, disc granulation integration technology of preparing is prepared, obtain low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, the overall release rate of fertiliser granulates is reduced, thus also reach the slowly-releasing of phosphorus, potassium, its fertilizer nutrient rate of release and crop nutrition content absorbing rule are matched, effectively can improve utilization rate of fertilizer, reduce chemical fertilizer to the pollution of environment, more remarkable to increasing crop yield effect.

Background technology

Chemical fertilizer is the material guarantee of agricultural sustainable development, be the basis of increases in grain production, at present, China has become chemical fertilizers production state maximum in the world and country of consumption, but, according to mensuration: in the general chemical fertilizer of China, utilization rate of nitrogen fertilizer is only 25% ~ 40%, and phosphate fertilizer only has 10% ~ 25%, potash fertilizer is 30% ~ 50%, the utilization ratio of chemical fertilizer is lower, cause manure resources to be wasted, cause the eutrophication pollution of water, increase agriculture production cost.Therefore, exploitation can improve utilization rate of fertilizer to greatest extent, reduces discharge, and can obtain again the slowly-releasing gentle control fertiliser production new technology of high yield, for Ensuring Food Safety, preserving the ecological environment is extremely important.

Slow release fertilizer mainly comprises two large classes, one class is the slow release fertilizer made by chemical reaction, general solubleness in water is very little, after being manured into soil, at chemistry with under the factor effect of biology, fertilizer decomposes gradually, slowly releases nutrient, as slightly soluble organic nitrogenous fertilizers such as urea formaldehyde, iso-butylene diureas, the slightly soluble inorganic nitrogenous fertilizers etc. such as metal phosphorus ammonium salt, partial acidification phosphoric acid salt; Another kind of is the release and release control fertilizer made by parcel mode; take granular chemical fertilizer as core; top layer applies inorganic substance or the organic polymer of one deck low water solubility or microsolubility; to be spread by coating or coating decomposes and Releasing nutrient gradually; as organic polymer coated fertilizers such as thermohardening resin coated fertilizer, thermoplastic resin membrane wrapping fertilizer, the inorganic coating fertilizer etc. such as sulfur coated urea, mineral substance coat fertilizer.Although output and the usage quantity of slowly/controlled releasing fertilizer increase year by year, because its production cost and market value are relatively high, can't be widely accepted at present, be still a very little ratio compared with normally used quick-acting chemical fertilizer.

Urea-formaldehyde resin be by urea and formaldehyde under katalysis through thermosetting polymer tackiness agent that addition and polycondensation generate.At present, the production of wood-based plate and the preparation etc. of slow release fertilizer is mainly used in China.In recent years, the conjunction condition of people to urea-formaldehyde resin has carried out large quantifier elimination, and research shows that its preparation technology is: urea: formaldehyde=1.0:1.0 ~ 1.0:1.4; divide and add urea 3 ~ 4 times; temperature of reaction is more than 80 degrees Celsius; reaction times 90 ~ 180min.The mol ratio of existing processing condition urea and formaldehyde is higher, and main it is considered that the cohesive strength of urea-formaldehyde resin, the content of free formaldehyde is higher, and temperature of reaction is more than 80 degrees Celsius in addition, and energy consumption is high, and the time is long, complicated operation, and reaction process is wayward.

Urea formaldehyde slow-release compound fertilizer is that urea and methyl alcohol at high temperature condensation reaction generate colloid mixture, synthesize granulation, the slow-release compound fertilizer of formation with phosphate fertilizer and potash fertilizer again, belong to the high-end product in fertilizer, because cost is higher, be mainly used on golf course lawn and high-grade view flowers.Urea formaldehyde is more ripe slow release fertilizer, abroad just proposes than more complete procedure of laboratory as far back as the later stage thirties 20th century.Nineteen fifty-five, BASF Corp. of Germany carries out merchandized handling.1984, USSR (Union of Soviet Socialist Republics) had the report being added in urea-formaldehyde fertilizer by potassium sulfate and improve sand ground water-retentivity.Nineteen ninety, the Worsley. Michael paraformaldehyde of the U.S. and urea reaction have synthesized solid-state urea aldehyde slow release fertilizer.Recently, Japan's development excess of export slow urea formaldehyde nitrogenous fertilizer, UF urea combination-potassium sulfate-phosphorus-ammonium compound fertilizer material; The U.S. then develops the urea aldehyde disperse fertilizer with package stability, and by the high molecular slow-release composite fertilizer of urea formaldehyde and phosphoric acid-potassium primary phosphate mixed solution Reactive Synthesis.At present, China is also in the starting stage for the development of urea formaldehyde slowly/controlled releasing fertilizer, after developing urea formaldehyde slow release fertilizer, does not obtain very fast development within the long term from 1971.The complex manufacturing of urea formaldehyde slowly/controlled releasing fertilizer, key equipment is relative with the research of process matching weak, is difficult to form scale industrialization.Urea formaldehyde composite fertilizer master has two kinds, and one is by bread one deck urea-formaldehyde resin outside composite fertilizer, and plays slow/controlled release effect, claims urea-formaldehyde resin dressing composite fertilizer; Another kind is joined by powdery urea resin in the raw material of production composite fertilizer, and the composite fertilizer of production claims built-in urea formaldehyde composite fertilizer.

Composite fertilizer's nutritive element kind is more, and nutrient content is higher, and for balance fertilizing, improving utilization rate of fertilizer has very important effect.Composite fertilizer generally more makes particle, and water absorbability is little, prevented from caking, is convenient to storage and uses.The Technology of production composite fertilizer of China mainly contains: slurry process: with phosphoric acid, ammonia for raw material, utilize neutralizer, tubular reactor by and slip in ammoniation and granulation device, carry out coating granulation, in process of production adding portion nitrogen and potassium element etc.; part slurry process: directly spray in tablets press bed with urine or ammonium nitrate strong solution, carries out coating granulation with other solid base fertilizer. solid granulating method: with monomer base fertilizer for raw material, after being crushed to certain fineness, material carries out agglomeration granulation by humidification, heating in the rolling bed of tablets press. blending method: with the various basically identical nitrogen of obvious chemical reaction, granularity and circularity, phosphorus, each solid base fertilizer of potassium of not occurring for raw material, be mixed with the uniform bulk blended fertilizer of Nutrient distribution by certain mixing method.Shape and the specification of current China base fertilizer still do not possess this condition. extrusion process: extruder grain is that solid materials relies on external pressure to carry out the dry granulation of reuniting. melting method: the intermediates urea soln utilizing urea plant, is equipped with phosphorus ammonium, sylvite, prepares the production technology-fused mass granulating technique of urea-base compound fertilizer.Fused mass granulating technique is applied in chemical fertilizers production, sprinkling pelleting as tower in urea, the granulation of ammonium nitrate spray tower etc.But this technique still belongs to blank at home for the manufacture of urea-base compound fertilizer.These preparation technologies generally adopt stirring-type hybrid technology to carry out mixed chemical reaction process, and churning time is long, and energy consumption is large.At present, the technology & equipment of China advanced person is primarily of external introduction, although these technology and equipments serve important pushing effect to the starting of the phosphorus compound fertilizer industry of China and development.

The gypsum resource of China is extremely abundant, nearly 60,000,000,000 tons of explored natural crystal reserves, rank first in the world, about 2,000 ten thousand tons/year of the plaster of paris exploited at present, in addition, along with contemporary Chinese industrial expansion, the industrial gypsum (industry by-product gypsum) of about 3,000 ten thousand tons to be discharged every year, mainly phosphogypsum and desulfurated plaster.The Method and Technology of the comprehensive utilization industry by-product gypsum that cost of development is low, treatment capacity is large, was both conducive to protection of the environment, again can save energy and resource, and gypsum is rich in calcium, sulphur, and the nutritive element such as the necessary phosphorus of plant-growth, magnesium, iron, silicon.Determine that gypsum application has raising plant biomass and quality in agricultural, improve soil fertility, delays Soil degradation at present, reduce the effects such as heavy metal contamination, be widely used as sulphur, calcareous fertilisers and soil improvement agent, also can produce controlled availability fertilizer together with other fertilizer.This seminar for raw material with phosphogypsum and bicarbonate of ammonia, has prepared by solid-phase ball milling reaction the ammonium sulfate being used as fertilizer, the calcium sulfate of indissoluble in phosphogypsum has been converted into the ammonium sulfate (patent publication No. CN 101585547A) of solubility; Urea and the reaction of gypsum solid-phase ball milling, prepared the urea gypsum being used as fertilizer, this fertilizer has from slow-release function, and fertilizer efficiency period is long, higher than urea desorption column (patent publication No. CN 101798240A).With urea and the reacted urea gypsum masterbatch of gypsum, bicarbonate of ammonia and the reacted ammonium sulfate masterbatch of gypsum are main raw material, a certain amount of additive of Homogeneous phase mixing, go out controlled Nitrogen releasing speed through preparation, be applicable to the gypsum-based urea gypsum-urea-ammonium sulphate Controlled Release Nitrogen Fertilizer (patent publication No. CN 102167650A) of Different Crop growth demand.Pre-stage test shows, take gypsum as agricultural fertilizer prepared by raw material, can volume increase crop in various degree, improves utilization rate of fertilizer, simultaneously for the extensive process of phosphogypsum and desulfurated plaster and application provide an effective way.

Wilkinite is a kind of tonstein based on montmorillonite, has higher cation exchange capacity, stronger water retention capacity and good agglutinating value(of coal).Wilkinite may be used for improveing soil, also can prepare slow-release fertilizer as carrier, effectively improve chemical fertilizer utilization ratio, reduces environmental pollution.Explore shows, China's wilkinite proven reserve reach more than 50.87 hundred million tons, account for 60% of world's total amount, occupy first place in the world.Pan Yanfeng etc. utilize absorptiveminerals wilkinite to wrap up nitrogen, phosphorus, potash fertilizer to prepare release and release control fertilizer, analytical results shows that encapsulation process does not destroy the effective constituent of fertilizer, and wilkinite has good slow release effect to the Yi Rongfei such as nitrogen, potash fertilizer, and have indissoluble fertilizer such as phosphate fertilizer and short release effect.Luo Yangpo etc. with wilkinite and kaolin for carrier, polishing is adopted to prepare multiple clay-based nitrogen, phosphorus, potash fertilizer and composite fertilizer, and with leaching test evaluation the release performance of fertilizer, in the bentonite base composite fertilizer that result display is obtained, nitrogen, phosphorus, potassium all have good sustained release performance, with regard to rate of release, the rate of release of nitrogen is the fastest, and potassium takes second place, and phosphorus is the slowest.The result of study to several natural porous mineral/slow-release fertilizer of carbamide sustained releasing character such as Li Jinli shows that slow-release fertilizer slow release effect that wilkinite and urea is made into is obviously than the slow-release fertilizer had good sustained release effect that Rectorite Clay, attapulgite clay, clinoptilolite are made.Liu likes that equality research table wilkinite has good controlled-release function to potash fertilizer.Utilize wilkinite to prepare agricultural fertilizer as carrier, can not only fully Rational Utilization of Mineral Resources, improve the effective rate of utilization of fertilizer, agriculture production cost can also be reduced, reduce the environmental pollution that agricultural emissions causes, significant.

Summary of the invention

Object of the present invention is intended to overcome deficiency of the prior art, provides a kind of preparation method of low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.The present invention with low urea formaldehyde resin-composite gypsum material for sizing agent, composite with wilkinite again, form slow-releasing system, by extruding hybrid reaction, vibrosieve, disc granulation integration technology of preparing obtains the method for low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer; Adopt low formaldehyde-urea amount of substance ratio, prepare low aldehyde height nitrogen urea-formaldehyde resin, have energy consumption low under low temperature, weak acid medium condition, formaldehyde content is low and slowly-releasing nitrogen is high obtains feature, is particularly suitable for the preparation of slow release fertilizer; Urea-formaldehyde resin and semi-hydrated gypsum are mixed with out the Organic-inorganic composite binding agent as fertilizer in certain proportion, and the appropriate wilkinite preparation of remix is used as the composite slow release material of fertilizer; Based on this composite slow release material, add Slowly release nitrogen fertilizer (urea gypsum), instant nitrogenousfertilizer (ammonium sulfate), phosphorus fertilizer or potassium fertilizer (wherein have employed the ammonium sulfate and urea gypsum prepared by ball-milling reaction with bicarbonate of ammonia and urea respectively by gypsum especially), composition slow release fertilizer system; Because this system very easily forms sticky group, not by once extruding or a disk and complete granulation, the present invention proposes by extruding hybrid reaction, vibrosieve, and disc granulation integration technology of preparing prepares low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer; Urea-formaldehyde resin-semi-hydrated gypsum composite slow release material is the combination of organic-inorganic binder, effectively can control the nutrients release of composite fertilizer; By extruding, make mixing of materials evenly, reaction more abundant; Gypsum as sizing agent is semi-hydrated gypsum, there is water-absorbent, wilkinite also has excellent water-absorbent, both water regains are mated with urea-formaldehyde resin, ammonium sulfate, urea gypsum material moisture, can make no longer to add water in whole preparation technology, do not need to dry ammonium sulfate, urea gypsum material specially yet, thus the equipment investment saving dried material and bring and energy expenditure, be a kind of energy-saving processing technique.

Content of the present invention is: a kind of preparation method of low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, is characterized in that comprising the following steps:

A, prepare ammonium sulfate masterbatch: get gypsum (CaSO42H2O), bicarbonate of ammonia (NH4HCO3) is raw material, the stoichiometric ratio of chemical reaction is carried out, by the consumption of gypsum by weight percentage excessive 5% ~ 20% according to gypsum and bicarbonate of ammonia; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 3 ~ 5 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 10 ~ 15%, at normal temperatures, after ball-milling reaction 20 ~ 60min, namely obtain ammonium sulfate masterbatch, reaction conversion ratio is more than 95%, and the water content in ammonium sulfate masterbatch is about 25%;

B, preparation urea gypsum masterbatch: get gypsum (CaSO42H2O), urea (CO (NH4) 2) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 5% ~ 20%; Gypsum, urea are dropped in ball mill, by ball material weight ratio be 3 ~ 5 drop into abrading-balls, add the water of raw material gross weight 10 ~ 15%, at normal temperatures, after ball-milling reaction 20 ~ 40min, namely obtain urea gypsum masterbatch, reaction conversion ratio is 70 ~ 90%, in obtained urea gypsum masterbatch: urea gypsum state nitrogen accounts for 70 ~ 90%, and urea nitrogen accounts for 10 ~ 30%, and water content is about 18%;

C, prepare wilkinite: get natural montmorillonite ore deposit, drying or natural air drying, then be crushed to 60 ~ 200 orders, i.e. obtained wilkinite;

D, prepare semi-hydrated gypsum: by gypsum dry 30 ~ 50min at 120 ~ 150 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum (CaSO40.5H2O);

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio (i.e. mol ratio) of the amount of substance of 1: 0. 6 ~ 0.8 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde (such as: the there-necked flask in laboratory, industrial reaction vessel), start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 10 ~ 20min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction 40 ~ 60min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin, water content is about 26%,

F, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite: by low urea formaldehyde resin: semi-hydrated gypsum is the part by weight of 1:1.0 ~ 1.5, low urea formaldehyde resin and semi-hydrated gypsum are mixed, i.e. multiple/mixed sizing agent of obtained low urea formaldehyde resin-semi-hydrated gypsum; Again by multiple/mixed sizing agent of low urea formaldehyde resin-semi-hydrated gypsum: wilkinite is the part by weight of 3:1, multiple for low urea formaldehyde resin-semi-hydrated gypsum/mixed sizing agent and wilkinite are mixed, i.e. multiple/mixed slow-release material of obtained low urea formaldehyde resin-gypsum-wilkinite, the effective service life of multiple/mixed slow-release material of this low urea formaldehyde resin-gypsum-wilkinite is 2 hours;

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer: get the nitrogenous ammonium sulfate masterbatch for fertilizer total nitrogen 5 ~ 25%, get the nitrogenous urea gypsum masterbatch for fertilizer total nitrogen 75 ~ 95%, mix, obtained mixture;

Described nitrogenous be the ammonium sulfate masterbatch of fertilizer total nitrogen 5 ~ 25%, that is: in obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, the weight (quality) from nitrogen in ammonium sulfate masterbatch is 5 ~ 25% of weight nitroxide (quality) total in fertilizer.

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 5 ~ 10 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, again through swing crushing, screening, disc granulation, obtained any surface finish, density are high, particle diameter is the spheroidal particle of 3 ~ 6mm, be dried to water ratio again and be less than 2.5%, be i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.

In content of the present invention: gypsum described in steps d can be the plaster of paris, phosphogypsum or desulfurated plaster.

In content of the present invention: the phosphorous phosphorus fertilizer for fertilizer total nitrogen 20 ~ 150% can also be added with in mixture described in step g.That is: in obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, 20 ~ 150% of the weight (quality) that the weight (quality) of phosphorus is nitrogen.

In content of the present invention: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 20 ~ 150%.That is: in obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, 20 ~ 150% of the weight (quality) that the weight (quality) of potassium is nitrogen.

Compared with prior art, the present invention has features and beneficial effect:

(1) adopt the present invention, the low urea formaldehyde resin of acquisition has the feature that slow-release nitrogen content is high, cohesive strength meets fertilizer nutrient, and the preparation technology of proposition at normal temperatures, can complete in 40 ~ 50 minutes, does not need heating, good energy-conserving effect;

(2) the present invention is adopted, urea-formaldehyde resin-gypsum-wilkinite is Organic-inorganic composite bonding and slow-release material, comprehensive bonding and sustained release performance are better than independent urea-formaldehyde resin and gypsum, and urea-formaldehyde resin itself is excellent slow-release nitrogen fertilizer, easily be decomposed absorption in soil, not residual, the gypsum with microsolubility also can discharge calcium and sulfur fertilizer and produce fertilizer efficiency in soil, add the excellent water conservation of wilkinite and fertilizer conservation effect, make urea-formaldehyde resin-gypsum-wilkinite slow-releasing system better effects if, gypsum as sizing agent is semi-hydrated gypsum, there is water-absorbent, wilkinite also has excellent water-absorbent, by both water regains and urea-formaldehyde resin, ammonium sulfate, urea gypsum material moisture mates, can make no longer to add water in whole preparation technology, do not need special in ammonium sulfate yet, urea gypsum material is dried, thus the equipment investment saving dried material and bring and energy expenditure, it is a kind of energy-saving processing technique,

(3) the present invention adopts extruding hybrid reaction-vibrosieve-disc granulation integration technology of preparing to prepare slow release fertilizer.The preparation of this technique to urea-formaldehyde resin-gypsum-wilkinite slow release fertilizer is pointed, respond well.This slow-releasing system very easily forms sticky group, not by once extruding or a disk and complete granulation, urea-formaldehyde resin and gypsum are once mixing, must use in 2 hours, this all requires that this slow release fertilizer needs hybrid reaction-vibrosieve-disc granulation integration to complete, the mixing of storeroom adopts stirring can not reach fully mixing and reaction, by the mode of extruding mixing, just can make this mixing of materials evenly, sufficient reacting; Mixture is by being irregular sheet after extruding hybrid reaction, and after needing swing crushing, screening, directly enter disc granulation, granulation outcome is good;

(4) the present invention with gypsum (plaster of paris, phosphogypsum or desulfurated plaster) for main raw material, low urea formaldehyde resin-gypsum-bentonite base the slow-release fertilizer prepared, be rich in the SO42-of solubility, can according to each budding growth demand Releasing nutrient of crop, significantly can increase grain yield, improve utilization rate of fertilizer, reduce the environmental pollution that agricultural emissions causes, simultaneously for the comprehensive utilization of industrial gypsum provides effective way.Agricultural experiment in early stage result shows, under equal Fertilization Level, paddy rice, corn can increase production 8% ~ 15%, and utilization rate of nitrogen fertilizer can improve 15% ~ 30%.

Embodiment

Embodiment given below is intended so that the invention will be further described; but can not be interpreted as it is limiting the scope of the invention; some nonessential improvement and adjustment that person skilled in art makes the present invention according to the content of the invention described above, still belong to protection scope of the present invention.

The phosphogypsum base ammonium sulfate all used in embodiment 1 ~ 10, phosphogypsum base urea gypsum, phosphate fertilizer can be any one phosphorus fertilizer; Potash fertilizer can be any one potassium fertilizer.

Embodiment 1:

A preparation method for low urea formaldehyde resin-gypsum base slow-release rice nitrogenous fertilizer, its concrete preparation process comprises the following steps:

The first step, the preparation of ammonium sulfate: get phosphogypsum, bicarbonate of ammonia is raw material, according to the stoichiometric ratio of CaSO42H2O and NH4HCO3 reaction, by the consumption of CaSO42H2O by weight percentage excessive 5%; Gypsum, bicarbonate of ammonia are dropped in ball mill, be 5 input abrading-balls by ball material weight ratio, add the water of material dry weight 12%, at normal temperatures, after ball-milling reaction 20 min ~ 60min, namely obtain ammonium sulfate masterbatch, nitrogen content is 10.2%, water-content 24.5%.

Second step, the preparation of urea gypsum: get phosphogypsum, urea is raw material, according to the stoichiometric ratio that CaSO42H2O and CO (NH4) 2 reacts, by the consumption of CaSO42H2O by weight percentage excessive 5%; Gypsum, urea are dropped in ball mill, is 5 input abrading-balls by ball material weight ratio, adds the water of material dry weight 12%, at normal temperatures, after ball-milling reaction 20 min ~ 40min, urea gypsum masterbatch is namely obtained, urea nitrogen content is 8.3%, and urea gypsum state nitrogen content is 18.8%, water-content 18.3%.

3rd step, bentonitic preparation: natural montmorillonite ore deposit is dried or natural air drying, is crushed to 60 ~ 200 orders and namely obtains wilkinite.

4th step, the preparation of semi-hydrated gypsum: by phosphogypsum in 150 DEG C of oven dry, be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum CaSO40.5H2O.

5th step, the preparation of low urea formaldehyde resin: weigh urea and formaldehyde than 1: 0.8 with amount of substance, by load weighted urea with formaldehyde is disposable adds there-necked flask, start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 10 ~ 20min, after reaching cloud point, its pH to 5.0 ~ 6.0 are adjusted with sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction for some time, temperature is slowly down to 40 DEG C, its pH value 7.0 ~ 8.0 is adjusted with sodium hydroxide solution, cooling discharge, for oyster white jelly, water content is about 26%.

6th step, the preparation of multiple/mixed slow-release material of urea-formaldehyde resin-gypsum-wilkinite: the urea-formaldehyde resin and the semi-hydrated gypsum that take mass ratio 1:1.1 mix, prepares multiple/mixed sizing agent of urea-formaldehyde resin-semi-hydrated gypsum.Multiple/mixed sizing agent of urea-formaldehyde resin-semi-hydrated gypsum is mixed with out multiple/mixed slow-release material of urea-formaldehyde resin-gypsum-wilkinite with wilkinite with the mass ratio of 3:1 again.

7th step, takes the ammonium sulfate of 33.7 weight parts respectively, and the urea gypsum of 66.3 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release rice nitrogenous fertilizer can be obtained.

Embodiment 2:

A preparation method for low urea formaldehyde resin-gypsum base slow-release rice composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, take the ammonium sulfate of 10.2 weight parts respectively, the urea gypsum of 20.0 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 57.8 weight parts, the Repone K (potassium content 46.5%) of 12 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release rice composite fertilizer can be obtained.

Embodiment 3:

A preparation method for low urea formaldehyde resin-gypsum base slow-release corn nitrogenous fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, takes the ammonium sulfate of 37.5 weight parts respectively, and the urea gypsum of 62.5 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release corn nitrogenous fertilizer can be obtained.

Embodiment 4:

A preparation method for low urea formaldehyde resin-gypsum base slow-release corn composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, take the ammonium sulfate of 11.2 weight parts respectively, the urea gypsum of 18.7 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 58.0 weight parts, the Repone K (potassium content 46.5%) of 12.1 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release corn composite fertilizer can be obtained.

Embodiment 5:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing Nitrogen Fertilizer On Soybeans, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, takes the ammonium sulfate of 30.8 weight parts respectively, and the urea gypsum of 69.2 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing Nitrogen Fertilizer On Soybeans can be obtained.

Embodiment 6:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing soybean composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, take the ammonium sulfate of 8.2 weight parts respectively, the urea gypsum of 20.4 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 59.1 weight parts, the Repone K (potassium content 46.5%) of 12.3 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing soybean composite fertilizer can be obtained.

Embodiment 7:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing wheat nitrogenous fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, takes the ammonium sulfate of 46.1 weight parts respectively, and the urea gypsum of 53.9 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing wheat nitrogenous fertilizer can be obtained.

Embodiment 8:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing wheat composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, take the ammonium sulfate of 21.5 weight parts respectively, the urea gypsum of 25.2 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 44.6 weight parts, the Repone K (potassium content 46.5%) of 8.7 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing wheat composite fertilizer can be obtained.

Embodiment 9:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing rape nitrogenous fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, takes the ammonium sulfate of 71.8 weight parts respectively, and the urea gypsum of 28.2 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing rape nitrogenous fertilizer can be obtained.

Embodiment 10:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing rape composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 1.

7th step, take the ammonium sulfate of 33.5 weight parts respectively, the urea gypsum of 13.4 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 44.2 weight parts, the Repone K (potassium content 46.5%) of 8.9 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing rape composite fertilizer can be obtained.

The desulfurized gypsum base ammonium sulfate all used in embodiment 11 ~ 20, desulfurized gypsum base urea gypsum, phosphate fertilizer can be any one phosphorus fertilizer; Potash fertilizer can be any one potassium fertilizer.

Embodiment 11:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing Chinese cabbage nitrogenous fertilizer, its concrete preparation process comprises the following steps:

The first step, the preparation of ammonium sulfate: get desulfurated plaster, bicarbonate of ammonia is raw material, according to the stoichiometric ratio of CaSO42H2O and NH4HCO3 reaction, by the consumption of CaSO42H2O by weight percentage excessive 5%; Gypsum, bicarbonate of ammonia are dropped in ball mill, be 5 input abrading-balls by ball material weight ratio, add the water of material dry weight 12%, at normal temperatures, after ball-milling reaction 20 min ~ 60min, namely obtain ammonium sulfate masterbatch, nitrogen content is 11.3%, water-content 23.0%.

Second step, the preparation of urea gypsum: get desulfurated plaster, urea is raw material, according to the stoichiometric ratio that CaSO42H2O and CO (NH4) 2 reacts, by the consumption of CaSO42H2O by weight percentage excessive 5%; Gypsum, urea are dropped in ball mill, is 5 input abrading-balls by ball material weight ratio, adds the water of material dry weight 12%, at normal temperatures, after ball-milling reaction 20 min ~ 40min, urea gypsum masterbatch is namely obtained, urea nitrogen content is 8.7%, and urea gypsum state nitrogen content is 19.6%, water-content 17.8%.

4th step, the preparation of semi-hydrated gypsum: by desulfurated plaster in 150 DEG C of oven dry, be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum CaSO40.5H2O.

7th step, takes the ammonium sulfate of 61.8 weight parts respectively, and the urea gypsum of 38.2 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing Chinese cabbage nitrogenous fertilizer can be obtained.

Embodiment 12:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing Chinese cabbage composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 11.

7th step, take the ammonium sulfate of 33.6 weight parts respectively, the urea gypsum of 20.8 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 26.9 weight parts, the Repone K (potassium content 46.5%) of 18.7 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing Chinese cabbage composite fertilizer can be obtained.

Embodiment 13:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing radish nitrogenous fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 11.

7th step, takes the ammonium sulfate of 63.4 weight parts respectively, and the urea gypsum of 36.6 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing radish nitrogenous fertilizer can be obtained.

Embodiment 14:

A preparation method for low urea formaldehyde resin-gypsum base slowly-releasing radish composite fertilizer, its concrete preparation process comprises the following steps:

The preparation process the first step to the 6th step with embodiment 11.

7th step, take the ammonium sulfate of 42.6 weight parts respectively, the urea gypsum of 24.6 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 16.5 weight parts, the Repone K (potassium content 46.5%) of 16.3 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing radish composite fertilizer can be obtained.

Embodiment 15:

The preparation process the first step to the 6th step with embodiment 11.

7th step, takes the ammonium sulfate of 30.5 weight parts respectively, and the urea gypsum of 69.5 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing Nitrogen Fertilizer On Soybeans can be obtained.

Embodiment 16:

The preparation process the first step to the 6th step with embodiment 11.

7th step, take the ammonium sulfate of 7.8 weight parts respectively, the urea gypsum of 20.1 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 59.4 weight parts, the Repone K (potassium content 46.5%) of 12.7 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slowly-releasing soybean composite fertilizer can be obtained.

Embodiment 17:

The preparation process the first step to the 6th step with embodiment 11.

7th step, takes the ammonium sulfate of 33.2 weight parts respectively, and the urea gypsum of 66.8 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release rice nitrogenous fertilizer can be obtained.

Embodiment 18:

The preparation process the first step to the 6th step with embodiment 11.

7th step, take the ammonium sulfate of 9.9 weight parts respectively, the urea gypsum of 19.8 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 58.1 weight parts, the Repone K (potassium content 46.5%) of 12.2 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release rice composite fertilizer can be obtained.

Embodiment 19:

The preparation process the first step to the 6th step with embodiment 11.

7th step, takes the ammonium sulfate of 36.8 weight parts respectively, and the urea gypsum of 63.2 weight parts, mixes, and adds multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release corn nitrogenous fertilizer can be obtained.

Embodiment 20:

The preparation process the first step to the 6th step with embodiment 11.

7th step, take the ammonium sulfate of 10.5 weight parts respectively, the urea gypsum of 18.3 weight parts, the calcium superphosphate (phosphorus content 11.3%) of 58.7 weight parts, the Repone K (potassium content 46.5%) of 12.5 weight parts, mix, add multiple/mixed slow-release material of its weight 15% urea-formaldehyde resin-gypsum-wilkinite to this mixture; By repeatedly extruding 5 ~ 10 times, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation obtains any surface finish, density is high, and particle diameter is the spheroidal particle of 3 ~ 6mm; Be dried to water ratio and be less than 2.5%, low urea formaldehyde resin-gypsum-bentonite base slow-release corn composite fertilizer can be obtained.

Embodiment 21:

A preparation method for low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, comprises the following steps:

A, prepare ammonium sulfate masterbatch: get gypsum (CaSO42H2O), bicarbonate of ammonia (NH4HCO3) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and bicarbonate of ammonia, by the consumption of gypsum by weight percentage excessive 12%; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 4 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 13%, at normal temperatures, after ball-milling reaction 40min, namely obtain ammonium sulfate masterbatch;

B, preparation urea gypsum masterbatch: get gypsum (CaSO42H2O), urea (CO (NH4) 2) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 12%; Gypsum, urea are dropped in ball mill, is 4 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 13%, at normal temperatures, after ball-milling reaction 30min, namely obtain urea gypsum masterbatch;

D, prepare semi-hydrated gypsum: by gypsum dry 40min at 140 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum (CaSO40.5H2O);

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio (i.e. mol ratio) of the amount of substance of 1: 0. 7 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde (such as: the there-necked flask in laboratory, industrial reaction vessel), start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 15min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction 50min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin, water content is about 26%,

F, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite: by low urea formaldehyde resin: semi-hydrated gypsum is the part by weight of 1:1.3, low urea formaldehyde resin and semi-hydrated gypsum are mixed, i.e. multiple/mixed sizing agent of obtained low urea formaldehyde resin-semi-hydrated gypsum; Again by multiple/mixed sizing agent of low urea formaldehyde resin-semi-hydrated gypsum: wilkinite is the part by weight of 3:1, multiple for low urea formaldehyde resin-semi-hydrated gypsum/mixed sizing agent and wilkinite are mixed, i.e. multiple/mixed slow-release material of obtained low urea formaldehyde resin-gypsum-wilkinite;

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer: get the nitrogenous ammonium sulfate masterbatch for fertilizer total nitrogen 15%, get the nitrogenous urea gypsum masterbatch for fertilizer total nitrogen 85%, mix, obtained mixture;

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 8 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, again through swing crushing, screening, disc granulation, obtained any surface finish, density are high, particle diameter is the spheroidal particle of 3 ~ 6mm, drying is less than 2.5% to water ratio again, i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.

Embodiment 22:

A, prepare ammonium sulfate masterbatch: get gypsum (CaSO42H2O), bicarbonate of ammonia (NH4HCO3) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and bicarbonate of ammonia, by the consumption of gypsum by weight percentage excessive 5%; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 3 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 10%, at normal temperatures, after ball-milling reaction 20min, namely obtain ammonium sulfate masterbatch;

B, preparation urea gypsum masterbatch: get gypsum (CaSO42H2O), urea (CO (NH4) 2) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 5%; Gypsum, urea are dropped in ball mill, is 3 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 10%, at normal temperatures, after ball-milling reaction 20min, namely obtain urea gypsum masterbatch;

D, prepare semi-hydrated gypsum: by gypsum dry 50min at 120 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum (CaSO40.5H2O);

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio (i.e. mol ratio) of the amount of substance of 1: 0. 6 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde (such as: the there-necked flask in laboratory, industrial reaction vessel), start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 10min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction 40min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin, water content is about 26%,

F, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite: by low urea formaldehyde resin: semi-hydrated gypsum is the part by weight of 1:1.0, low urea formaldehyde resin and semi-hydrated gypsum are mixed, i.e. multiple/mixed sizing agent of obtained low urea formaldehyde resin-semi-hydrated gypsum; Again by multiple/mixed sizing agent of low urea formaldehyde resin-semi-hydrated gypsum: wilkinite is the part by weight of 3:1, multiple for low urea formaldehyde resin-semi-hydrated gypsum/mixed sizing agent and wilkinite are mixed, i.e. multiple/mixed slow-release material of obtained low urea formaldehyde resin-gypsum-wilkinite;

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer: get the nitrogenous ammonium sulfate masterbatch for fertilizer total nitrogen 5%, get the nitrogenous urea gypsum masterbatch for fertilizer total nitrogen 95%, mix, obtained mixture;

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 5 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, again through swing crushing, screening, disc granulation, obtained any surface finish, density are high, particle diameter is the spheroidal particle of 3 ~ 6mm, drying is less than 2.5% to water ratio again, i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.

Embodiment 23:

A, prepare ammonium sulfate masterbatch: get gypsum (CaSO42H2O), bicarbonate of ammonia (NH4HCO3) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and bicarbonate of ammonia, by the consumption of gypsum by weight percentage excessive 20%; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 5 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 15%, at normal temperatures, after ball-milling reaction 60min, namely obtain ammonium sulfate masterbatch;

B, preparation urea gypsum masterbatch: get gypsum (CaSO42H2O), urea (CO (NH4) 2) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 20%; Gypsum, urea are dropped in ball mill, is 5 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 15%, at normal temperatures, after ball-milling reaction 40min, namely obtain urea gypsum masterbatch;

D, prepare semi-hydrated gypsum: by gypsum dry 50min at 150 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum (CaSO40.5H2O);

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio (i.e. mol ratio) of the amount of substance of 1: 0.8 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde (such as: the there-necked flask in laboratory, industrial reaction vessel), start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 20min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction 60min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin, water content is about 26%,

F, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite: by low urea formaldehyde resin: semi-hydrated gypsum is the part by weight of 1:1.5, low urea formaldehyde resin and semi-hydrated gypsum are mixed, i.e. multiple/mixed sizing agent of obtained low urea formaldehyde resin-semi-hydrated gypsum; Again by multiple/mixed sizing agent of low urea formaldehyde resin-semi-hydrated gypsum: wilkinite is the part by weight of 3:1, multiple for low urea formaldehyde resin-semi-hydrated gypsum/mixed sizing agent and wilkinite are mixed, i.e. multiple/mixed slow-release material of obtained low urea formaldehyde resin-gypsum-wilkinite;

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer: get the nitrogenous ammonium sulfate masterbatch for fertilizer total nitrogen 25%, get the nitrogenous urea gypsum masterbatch for fertilizer total nitrogen 75%, mix, obtained mixture;

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 10 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, again through swing crushing, screening, disc granulation, obtained any surface finish, density are high, particle diameter is the spheroidal particle of 3 ~ 6mm, drying is less than 2.5% to water ratio again, i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.

Embodiment 24:

A, prepare ammonium sulfate masterbatch: get gypsum (CaSO42H2O), bicarbonate of ammonia (NH4HCO3) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and bicarbonate of ammonia, by the consumption of gypsum by weight percentage excessive 9%; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 4 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 11%, at normal temperatures, after ball-milling reaction 30min, namely obtain ammonium sulfate masterbatch;

B, preparation urea gypsum masterbatch: get gypsum (CaSO42H2O), urea (CO (NH4) 2) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 9%; Gypsum, urea are dropped in ball mill, is 3 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 11%, at normal temperatures, after ball-milling reaction 30min, namely obtain urea gypsum masterbatch;

D, prepare semi-hydrated gypsum: by gypsum dry 35min at 120 ~ 150 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum (CaSO40.5H2O);

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio (i.e. mol ratio) of the amount of substance of 1: 0. 6 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde (such as: the there-necked flask in laboratory, industrial reaction vessel), start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 12min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction 45min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin, water content is about 26%,

F, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite: by low urea formaldehyde resin: semi-hydrated gypsum is the part by weight of 1:1.1, low urea formaldehyde resin and semi-hydrated gypsum are mixed, i.e. multiple/mixed sizing agent of obtained low urea formaldehyde resin-semi-hydrated gypsum; Again by multiple/mixed sizing agent of low urea formaldehyde resin-semi-hydrated gypsum: wilkinite is the part by weight of 3:1, multiple for low urea formaldehyde resin-semi-hydrated gypsum/mixed sizing agent and wilkinite are mixed, i.e. multiple/mixed slow-release material of obtained low urea formaldehyde resin-gypsum-wilkinite;

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer: get the nitrogenous ammonium sulfate masterbatch for fertilizer total nitrogen 10%, get the nitrogenous urea gypsum masterbatch for fertilizer total nitrogen 90%, mix, obtained mixture;

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 7 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, again through swing crushing, screening, disc granulation, obtained any surface finish, density are high, particle diameter is the spheroidal particle of 3 ~ 6mm, drying is less than 2.5% to water ratio again, i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.

Embodiment 25:

A, prepare ammonium sulfate masterbatch: get gypsum (CaSO42H2O), bicarbonate of ammonia (NH4HCO3) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and bicarbonate of ammonia, by the consumption of gypsum by weight percentage excessive 18%; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 5 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 14%, at normal temperatures, after ball-milling reaction 50min, namely obtain ammonium sulfate masterbatch;

B, preparation urea gypsum masterbatch: get gypsum (CaSO42H2O), urea (CO (NH4) 2) is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 18%; Gypsum, urea are dropped in ball mill, is 4 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 14%, at normal temperatures, after ball-milling reaction 35min, namely obtain urea gypsum masterbatch;

D, prepare semi-hydrated gypsum: by gypsum dry 40min at 120 ~ 150 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum (CaSO40.5H2O);

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio (i.e. mol ratio) of the amount of substance of 1: 0.8 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde (such as: the there-necked flask in laboratory, industrial reaction vessel), start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 18min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, because this reaction is thermopositive reaction, self-heat generation is enough to provide polycondensation temperature required, after reaction 55min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin, water content is about 26%,

F, prepare multiple/mixed slow-release material of low urea formaldehyde resin-gypsum-wilkinite: by low urea formaldehyde resin: semi-hydrated gypsum is the part by weight of 1:1.4, low urea formaldehyde resin and semi-hydrated gypsum are mixed, i.e. multiple/mixed sizing agent of obtained low urea formaldehyde resin-semi-hydrated gypsum; Again by multiple/mixed sizing agent of low urea formaldehyde resin-semi-hydrated gypsum: wilkinite is the part by weight of 3:1, multiple for low urea formaldehyde resin-semi-hydrated gypsum/mixed sizing agent and wilkinite are mixed, i.e. multiple/mixed slow-release material of obtained low urea formaldehyde resin-gypsum-wilkinite;

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer: get the nitrogenous ammonium sulfate masterbatch for fertilizer total nitrogen 20%, get the nitrogenous urea gypsum masterbatch for fertilizer total nitrogen 80%, mix, obtained mixture;

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 9 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, again through swing crushing, screening, disc granulation, obtained any surface finish, density are high, particle diameter is the spheroidal particle of 3 ~ 6mm, drying is less than 2.5% to water ratio again, i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer.

In above-described embodiment 21-25: gypsum described in steps d can be the plaster of paris, phosphogypsum or desulfurated plaster.

In above-described embodiment 21-25: the phosphorous phosphorus fertilizer for fertilizer total nitrogen 20 ~ 150% can also be added with in mixture described in step g.That is: in obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, 20 ~ 150% of the weight (quality) that the weight (quality) of phosphorus is nitrogen.

In above-described embodiment 21-25: can also be added with the phosphorous phosphorus fertilizer for fertilizer total nitrogen 20% in mixture described in step g, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with the phosphorous phosphorus fertilizer for fertilizer total nitrogen 150% in mixture described in step g, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with the phosphorous phosphorus fertilizer for fertilizer total nitrogen 85% in mixture described in step g, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with the phosphorous phosphorus fertilizer for fertilizer total nitrogen 50% in mixture described in step g, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with the phosphorous phosphorus fertilizer for fertilizer total nitrogen 120% in mixture described in step g, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 20 ~ 150%.That is: in obtained low urea formaldehyde resin-gypsum-bentonite base slow release fertilizer, 20 ~ 150% of the weight (quality) that the weight (quality) of potassium is nitrogen.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 20%, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 150%, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 80%, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 50%, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 100%, other is with corresponding embodiment.

In above-described embodiment 21-25: can also be added with in mixture described in step g containing potassium is the potassium fertilizer of fertilizer total nitrogen 120%, other is with corresponding embodiment.

In above-described embodiment: each raw material adopted is commercially available prod.

In above-described embodiment: in the percentage adopted, do not indicate especially, be weight (quality) percentage; Described weight (quality) part can be all gram or kilogram.

In above-described embodiment: the processing parameter in each step and each amounts of components numerical value etc. are scope, and any point is all applicable.

The concrete same prior art of technology contents described in content of the present invention and above-described embodiment.

The invention is not restricted to above-described embodiment, all can implement described in content of the present invention and there is described good result.

Claims

1. a preparation method for low urea formaldehyde resin-gypsum-bentonite base slow-release rice compound manure, is characterized in that comprising the following steps:

A, prepare ammonium sulfate masterbatch: get gypsum, bicarbonate of ammonia is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and bicarbonate of ammonia, by the consumption of gypsum by weight percentage excessive 5%; Gypsum, bicarbonate of ammonia are dropped in ball mill, is 5 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 10 ~ 15%, at normal temperatures, after ball-milling reaction 20 ~ 60min, namely obtain ammonium sulfate masterbatch;

B, preparation urea gypsum masterbatch: get gypsum, urea is raw material, carry out the stoichiometric ratio of chemical reaction according to gypsum and urea, by the consumption of gypsum by weight percentage excessive 5% ~ 20%; Gypsum, urea are dropped in ball mill, is 3 ~ 5 input abrading-balls by ball material weight ratio, adds the water of raw material gross weight 12%, at normal temperatures, after ball-milling reaction 40min, namely obtain urea gypsum masterbatch;

D, prepare semi-hydrated gypsum: by gypsum dry 50min at 150 DEG C of temperature, then be crushed to 60 ~ 200 orders, namely obtain semi-hydrated gypsum;

E, prepare low urea formaldehyde resin: in urea: formaldehyde is that the ratio of the amount of substance of 1: 0.8 gets urea and formaldehyde, by in urea and the disposable input reaction vessel of formaldehyde, start to heat and stir, heating is stopped when temperature rises to 25 DEG C, after urea dissolves completely, with hydrochloric acid or sulfuric acid adjust pH to 4.0 ~ 5.0, reaction 10 ~ 20min, after reaching cloud point, pH to 5.0 ~ 6.0 are adjusted with aqueous sodium hydroxide solution, after reaction 40min, temperature is slowly down to 40 DEG C, pH to 7.0 ~ 8.0 are adjusted with aqueous sodium hydroxide solution, be cooled to room temperature, obtain oyster white jelly, i.e. obtained low urea formaldehyde resin,

G, prepare low urea formaldehyde resin-gypsum-bentonite base slow-release rice compound manure: get 10.2 parts sulfuric acid ammonium masterbatch, 20.0 parts by weight of urea gypsum masterbatch, the calcium superphosphate of 57.8 weight parts, the Repone K of 12 weight parts, mixes, obtained mixture;

Multiple/mixed slow-release material of the low urea formaldehyde resin-gypsum-wilkinite of mixture weight 15% is added to mixture; 10 times are repeatedly extruded by extrusion machine, make its abundant hybrid reaction, then through swing crushing, screening, disc granulation, obtained particle diameter is the spheroidal particle of 3 ~ 6mm, drying is less than 2.5% to water ratio again, i.e. obtained low urea formaldehyde resin-gypsum-bentonite base slow-release rice compound manure.