CN1390812A

CN1390812A - Adhesive for granulating mixed organic fertilizer and its preparing process

Info

Publication number: CN1390812A
Application number: CN 02123522
Authority: CN
Inventors: 张夫道
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-02
Filing date: 2002-07-02
Publication date: 2003-01-15

Abstract

An adhesive for granulating the composite organic fertilizer with high N, P, K and organic substance contents is prepared from polyvinyl methyral, hydroxymethy polycryamide, and cross-linked starch through proportional mixing and modifying by surfactant Amway.

Description

Organic compound fertilizer granulation binder and production method thereof

The invention relates to a production process flow of an organic material granulation binder for granulating organic compound fertilizers and a granulation application technology for producing urban organic waste fermentation materials.

Foreign livestock and poultry farms belong to individual operation basically, the scale of the livestock and poultry farms is mainly medium and small, and the excrement of the livestock andpoultry farms is fermented on site and used on site; in Europe and America, the planting industry is mostly one season in one year, and the straws are ground and rolled on the spot. The excrement of the large-scale livestock and poultry farm in China has the production capacity of about 3 hundred million tons each year, a chicken farm with 100 ten thousand feathers, a pig farm with more than 1 ten thousand feathers and even a pig farm with more than 20 ten thousand feathers are also established in a mutual competition; most areas of the planting system are double cropping in one year, the quantity of the straws is large, the time interval between harvesting and sowing is short, the straws cannot be turned over and pressed, and due to the change of rural energy structure, more than 1/3 (2.5 hundred million tons) of straws are surplus in China. The production amount of municipal domestic waste is 2 hundred million tons per year, organic matters account for 45 to 60 percent and are not effectively utilized basically, so that the resource utilization of agricultural wastes and municipal organic waste in China becomes an urgent affair.

At present, the granulation process of organic materials has the following two main types: namely extrusion granulation, and strip (also called rod) and spherical organic compound fertilizer is produced; sludge or clay is used as binder to produce round granular organic compound fertilizer.

The domestic organic material granulation process has the following defects: (1) strip-shaped and spherical organic compound fertilizer applying machines produced by extrusion cannot be applied, the water content is more than 20 percent, the organic compound fertilizer applying machines are easy to break in the transportation process, and the organic compound fertilizer is easy to mildew at high temperature (the water content of organic materials is more than 15 percent); (2) the sludge or clay is used as a binder, is suitable for treating and utilizing municipal sludge and excrement, is not suitable for producing the round granular organic compound fertilizer by large-scale livestock and poultry farm excrement, crop straws and municipal organic fermentation materials, particularly for producing the organic compound fertilizer with more than 30 percent of available nutrients, and cannot be added.

The commercialization of organic fertilizers is a difficult problem of granulation of organic materials, and long-distance transportation and mechanized fertilization cannot be realized without manufacturing round particles with certain crushing resistance.

The invention aims to solve the key problem in the granulation of organic materials, and aims to find a proper granulation binder which is suitable for the granulation of organic fermentation materials and does not cause environmental pollution.

Production process and application technology of efficient organic compound fertilizer granulation binder

The process flow diagram of the macromolecular granulation binder is shown in the attached figure 1 of the specification.

The production process of the granulation binder comprises the following 5 steps:

(1) preparation of polyvinyl formal

The polyvinyl alcohol is dissolved in water and then is subjected to condensation reaction with formaldehyde in the presence of an acid catalyst to obtain the polyvinyl alcohol-formaldehyde resin composition, wherein the reaction comprises the following steps:

the excess formaldehyde reacts with urea to form methylol ureas:

(monohydroxymethylurea),

(bis hydroxymethyl urea).

The specific operation is as follows: completely dissolving polyvinyl alcohol at 90-95 ℃, cooling to 50-55 ℃, adding diluted formaldehyde aqueous solution, adding hydrochloric acid aqueous solution to adjust the pH to about 2, reacting at about 50 ℃ for 45-50 min, heating to about 75 ℃, continuing to react for 45-50 min, cooling to 60 ℃, and adding NaOH aqueous solution to neutralize to pH 7.0.

The dosage of raw materials is as follows: 100kg of polyvinyl alcohol, 40-50 kg of formaldehyde (40%), 1000kg of water, HCl and NaOH which are used for adjusting pH, and urea which is used for neutralizing redundant formaldehyde, wherein the using amount is determined according to needs.

(2) Preparation of hydroxymethylated polyacrylamide

The hydroxymethylation reaction of polyacrylamide and formaldehyde is faster under an alkaline condition (pH 8-10) than an acidic condition, and the reaction formula is as follows:

in actual operation, the pH of the polyacrylamide solution is adjusted to 10.2, formaldehyde is added, the mixture is stirred for 2 to 3 hours at about 30 ℃, and then HCl is used for adjusting the pH to 7.5.

The dosage of raw materials is as follows: 100kg of polyacrylamide, 1000kg of water, 25-30 kg of formaldehyde, NaOH and HCl for adjusting pH, wherein the dosage is determined according to needs.

(3) Preparation of crosslinked starch

Under the condition that an aldehyde compound is used as a cross-linking agent, the starch undergoes a cross-linking reaction.

Dispersing potato starch into slurry by using cold water in a kettle provided with a stirrer, adjusting the pH to 2.0-3.0 by using dilute sulfuric acid, heating to 90-95 ℃ for gelatinization for 1h, cooling to normal temperature, stirring for 30-40 min to perform preliminary crosslinking reaction if 40% of industrial formaldehyde solution is used, then heating to about 50 ℃, continuing the reaction for 2h, and adjusting the pH to about 7 by using NaOH or ammonia water.

The dosage of raw materials is as follows: potato starch 120-150 kg, 1000kg of water, 8-12 kg of 40% formaldehyde and H₂SO₄And NaOH is used for adjusting the pH value, and the dosage is determined according to the requirement.

(4) The first three products were mixed in a ratio (5: 3: 2) and modified with mixed surfactant Amway to produce polymeric granulation binder CF 2. Production process of nano-grade granulating binder

Adding dispersant sodium dodecyl benzene sulfonate (90: 10) into the granulation binder CF2, stirring, and performing high shear (2 ten thousand r/min) for 5-10 min to obtain the nanoscale granulation binder CF 3.

The high shear equipment is designed and processed by the inventor. The key parts are a motor (made by Germany) and a shearing knife and a closed metal cylinder, and the shearing knife is processed into a saw-tooth shape by adopting high-chromium high-nickel austenitic stainless steel (see attached figure 2).

Use of granulation Binder

(1) Dissolving CF2 with hot water (40-50 deg.C), diluting with hot water or cold water, and stirring with 300r/min stirrer for accelerating dissolution; CF3 can be dissolved in cold water under stirring.

(2) When a disk or drum granulator isused for granulation, diluted binder aqueous solution is sprayed into the materials under high pressure (more than 3kg) according to the required concentration, and the materials are sprayed while being stirred in a material mixing stirrer.

(3) The nano-sized granulation binder CF3 can be completely dissolved in water at normal temperature, and CF3 can be directly diluted with cold water while stirring. The organic fermentation materials do not need to be dried and crushed, chemical fertilizers such as crushed urea, ammonium phosphate, potassium chloride or potassium sulfate (which are proportioned according to the needs of crops) and the like can be added to carry out granulation in a disc or drum granulator, diluted binder aqueous solution is sprayed into a material mixer under high pressure (more than 3kg) according to the required concentration, and the adding amount of the binder aqueous solution is calculated according to the water content of the material of the disc granulator being 12-15% and the water content of the material of the drum granulator being 10-12%; the binder mother liquor with the dosage of 0.3 to 0.5 percent of the weight of the materials is sent to a mixer by a belt technology, evenly stirred and then granulated by a disk or drum granulator, dried by a rotary or drying cylinder, screened and then subpackaged.

The nano binder water solution nozzle is processed by Shanghai high bridge spraying systems, Inc., and has a pore diameter of phi 5 μm.

FIG. 1 Process flow diagram for pelletizing Binder FIG. 2 high shear device schematic

The invention has the characteristics that:

(1) the granulating binder is fully water-soluble, is suitable for granulating organic waste fermentation materials in urban and rural areas, can produce round-particle organic compound fertilizers with NPK effective content of more than 30% and organic matter content of more than 40%, has water content of 1.2% -1.7%, binder dosage of 0.3% -0.5% of fertilizer amount, granulation rate of more than 90%, and average particle crushing resistance of 10-15N, and the product meets the requirements of national standard GB 15063-94 of compound fertilizers and the industrial standard of organic compound fertilizers of Ministry of agriculture;

(2) the granulation binder can be completely degraded in soil within 3 months, and does not pollute the environment;

(3) the method is suitable for granulating by a rotary drum granulator and a disc granulator;

(4) is also suitable for granulating high-concentration inorganic compound fertilizer (N, P, K available nutrient is more than or equal to 45%).

Claims

1. An organic material granulation binder for granulation of an organic compound fertilizer is characterized in that the granulation binder is fully water-soluble, is suitable for granulation of urban and rural organic wastes, can produce N, P, K round-particle organic compound fertilizers with the effective content of more than 30 percent and the organic matter content of more than 40 percent, has the water content of 1.2 to 1.7 percent, the binder dosage of 0.3 to 0.5 percent of the fertilizer dosage, the granulation rate of more than 90 percent and the average crushing resistance of particles of 10 to 15N; the granulation binder can be completely degraded in soil within 3 months, and does not pollute the environment: it is suitable for granulating by drum granulator and disk granulator, and also suitable for granulating high-concentration inorganic compound fertilizer (N, P, K available nutrient is morethan 45%).

2. The production method of the compound fertilizer granulation binder of claim 1 is characterized in that polyvinyl formal, hydroxymethylated polyacrylamide and cross-linked starch are mixed according to a certain proportion and then modified by mixed surfactant Amway to produce the polymer granulation binder CF 2; CF2 is added with dispersant sodium dodecyl benzene sulfonate and processed into the nanoscale organic material granulation binder CF3 by high shear.

3. The production method of the compound fertilizer granulation binder of claim 2, wherein the polyvinyl formal is prepared by completely dissolving polyvinyl alcohol at 90-95 ℃, cooling to 50-55 ℃, adding diluted formaldehyde aqueous solution, adding hydrochloric acid aqueous solution (pH about 2), reacting at about 50 ℃ for 45-50 min, then heating to about 75 ℃, continuing to react for 45-50 min, cooling to 60 ℃, adding NaOH aqueous solution and ammonia water to neutralize the pH to 7.0.

The reaction is as follows:

the excess formaldehyde reacts with urea to form methylol ureas:

(monohydroxymethylurea) in the presence of a catalyst, (bis hydroxymethyl urea)

4. The production method of the compound fertilizer granulation binder as claimed in claim 2, wherein the hydroxymethylated polyacrylamide is prepared by adjusting the pH of polyacrylamide solution to 10.2, adding formaldehyde, stirring at about 30 ℃ for 2-3 hours, and adjusting the pH to 7.0.

The reaction formula is as follows:

5. the production method of the compound fertilizer granulation binder as claimed in claim 2, wherein the cross-linked starch is prepared by the cross-linking reaction of the starch under the condition that the aldehyde compound is used as the cross-linking agent, namely:

6. the production method of the compound fertilizer granulation binder as claimed in claim 2, wherein polyvinyl formal, hydroxymethylated polyacrylamide and crosslinked starch are mixed in a ratio of 5: 3: 2, and modified by mixed surfactant Amway to produce the granulation binder CF2 of the present invention.

7. The method for producing the compound fertilizer granulation binder as claimed in claim 2, wherein the polymeric granulation binder CF2 is prepared by adding sodium dodecylbenzenesulfonate as dispersant and processing into the nanoscale organic material granulation binder CF3 by high shear.

8. The method for producing the compound fertilizer granulation binder as claimed in claim 2, wherein the high shear equipment used in the processing of the nanoscale organic material granulation binder CF3 consists of a high-speed motor, a shear knife and a closed circular metal cylinder.

9. The use method of the granulation binder for the compound fertilizer as claimed in claim 1, wherein CF2 is dissolved by hot water of 40-50 ℃, diluted by hot water or cold water, and stirred by a 300r/min stirrer for accelerating dissolution; the CF3 can be directly diluted by cold water with stirring. Granulating in a disc or rotary drum granulator, and spraying the diluted binder aqueous solution into a material mixer by using high-pressure spray of more than 3kg according to the required concentration, wherein the adding amount of the binder aqueous solution is calculated according to the water content of the material of the disc granulator being 12-15% and the water content of the material of the rotary drum granulator being 10-12%; the binder mother liquor with the dosage of 0.3 to 0.5 percent of the weight of the materials is sent to a mixer by a belt technology, evenly stirred and then granulated by a disk or drum granulator, dried by a rotary or drying cylinder, screened and then subpackaged.