KR20010086703A - Process for preparing effects-controlled fertilizer and the product therefrom - Google Patents

Abstract

PURPOSE: Provided are a method of preparing dilatorily effective fertilizer which can control arbitrarily the flow rate of the fertilizer and reduce total usage of the fertilizer and fertilizer application time. CONSTITUTION: The method of preparing dilatorily effective fertilizer is characterized by the following steps: mixing and stirring conventional chemical fertilizer with caking urea-formaldehyde resin solution which is obtained by mixing formaldehyde and urea in a molar ratio of 0.5 to 1.5:1, and shaping under compression and coating the mixture. The caking resin solution is added in the amount of 5 to 30wt%. The urea-formaldehyde is, for example methylene-diurea, trimethylene-tetraurea, pentamethylene-hexaurea, methylenebis-acetylurea, monomethylolurea, monomethylolureamethylethyl, or monomethylolurea-dimethylether.

Description

Process for preparing effects-controlled fertilizer and the product therefrom}

The present invention relates to a method for producing a slow-fertilizing fertilizer and a product thereof. More specifically, the present invention relates to a caustic urea-formaldehyde resin solution having both an effect of a slow-fertilizing fertilizer and an adhesive effect by reacting urea and formalin as a slow-fertilizing fertilizer used in field crops. The present invention relates to a method for preparing a slow-release fertilizer and its preparation, which are synthesized and mixed with a general chemical fertilizer, followed by compression molding and coating.

Conventional chemical fertilizers that we usually use when used in the soil, the fertilizer component melts into the soil at once. However, since plants cannot absorb and use these fertilizers at once, the utilization rate of fertilizers is low, such as 30 to 40%, and the remainder is partially adsorbed to the soil, but is mostly lost by water or leached into groundwater. Lost or leached fertilizers can contaminate groundwater and flow into rivers and lakes, causing eutrophication.

In an attempt to solve the above problems, slow-fertilizing fertilizers have been developed. This slow-fertilizing fertilizer is a method of physically delaying the dissolution of fertilizers by coating poorly soluble chemicals with general fast-acting chemical fertilizers and a synthetic slow-fertilizer fertilizing fertilizers by chemically combining fertilizers with other substances. It can be divided into types.

Coating of poorly soluble materials is known by coating with sulfur, coating with thermosetting resin, coating with thermoplastic resin, and the like. Sulfur-coated fertilizer was developed by the US TVA in 1961 under the trade name Sulfur Coated Urea (SCU), and the fertilizer coated with thermosetting resin was coated with a mixture of glycerolester and dicyclopentadiene. Since it was developed in the United States in 1964 under the trade name Osmocote, it has been developed several similar products. Thermoplastic coating fertilizer is a slow-acting fertilizer that is coated with urea using polyolefin resin. Since it was developed in Japan in 1976 under the brand name Longcote, Nutricote, Lpcote and Meister ( Many similar products such as Meister are being developed and distributed.

Synthetic slow-acting fertilizers include urea-formaldehyde, isobutylaldehyde diurea (IBDU), crotonyliden diurea (CDU), and guanyl urea, and urea-formaldehyde is a condensation reaction between urea and formaldehyde. In 1955, the United States succeeded in industrialization for the first time, and IBDU was manufactured by reacting urea and isobutylaldehyde, and produced and sold in Japan. In addition, CDU was made by reacting urea and crotonaldehyde. Is commercialized and sold at. The CDU can also be made using aldol instead of crotonaldehyde. Recently, CDU can be obtained by reacting urea with acetylene.

The coating-activated fertilizer coated with the fertilizer with a polymer material of the above-mentioned slow-fertilizing fertilizer to control the dissolution rate of the fertilizer by adjusting the coating amount of the coating material. However, this is difficult to use for general agriculture because fertilizers are more than five times more expensive than general chemical fertilizers. In addition, since synthetically-activated fertilizers are expensive and chemically bound, it is difficult to arbitrarily adjust the dissolution rate of fertilizers, and because of the effects of soil acidity, temperature, and microorganisms, they have to be used in accordance with soil properties.

In addition, the soil of our country is granulated soil from granite or granite gneiss, and the utilization rate of nitrogen is low as low as 30 ~ 40% because of low organic content and nutrient preservation capacity. Therefore, in order to produce crops in the soil, fertilizers should be frequently used to provide adequate nutrients according to crop growth. When cultivating field crops, especially economic crops, fertilizers are often given 7 to 8 times. In addition, such soil may cause a lot of fertilizers to be used at one time, causing the use of fertilizer components to be lost, thereby degrading water quality such as rivers, rivers or lakes.

On the other hand, in the case of cultivating the field crops with vinyl, the fertilizers need to be drilled through the holes despite the high number of fertilizers, so it is not only inconvenient to give fertilizers but also a lot of efforts to give fertilizers. As the wages are rising, labor costs are increasing in the production of agricultural products.

Accordingly, the present inventors have conducted numerous studies and experiments to solve the above-mentioned problems. As a result, the present inventors synthesized a caking-based urea-formaldehyde resin solution having the effect of a slow-acting fertilizer and an adhesive effect by reacting urea and formalin. After mixing and mixing with general chemical fertilizer, compression molding and coating are used to prepare the slow-release fertilizer.The fertilizer dissolution rate can be arbitrarily adjusted according to the amount of the binder added or the coating amount. The total fertilizer use cost can be greatly reduced, and the fertilizer time and labor can be reduced, thereby improving the external competitiveness by reducing the production cost, and finding the surprising fact that there is little concern about environmental pollution because there is little loss of fertilizer. To complete.

The present invention provides a slow-acting fertilizer characterized by mixing and stirring a caking-based urea-formaldehyde resin solution in which a mixture of formaldehyde and urea in a molar ratio of (0.5 to 1.5): 1 is mixed with a conventional chemical fertilizer. It is about a method.

In the present invention, the urea-formaldehyde resin is methylene-diurea, trimethylene-tetraurea, pentamethylene-hexaurea, methylenebis-acetylurea, monomethylolurea, monomethylolureamethylethyl and monomethyl depending on the reaction. Olurea-dimethylether, dimethylolurea dimethylether, dimethylurea di-N-propylether, dimethylolurea di-N-amylether, dimethylolurea dibenzylether, dimethylolurea diethylthioether, tetramethylolurea Etc. can be used in various ways. However, in order to save the function as a fertilizer, it is possible as an initial reaction. In other words, as shown below, the function of fertilizer from monomethylolurea to trimethylene tetraurea is higher than that and the function of fertilizer is almost lost. In terms of fertilizer function, monomethylol urea and dimethylol urea have the highest dissolution of fertilizer components, and the dissolution rate is the highest, followed by monomethylene diurea, dimethylene triurea, and trimethylene tetraurea. It is slow and exhibits the properties of slow-release fertilizers.

Urea resin used as a caking agent in the method of the present invention can be prepared by the following method. Urea is weighed and placed in a reaction vessel containing formaldehyde. At this time, formaldehyde and urea are preferably mixed in a molar ratio of (0.1 to 1.5): 1. If it exceeds this molar ratio, it becomes insoluble and the fertilizer effect is weak. The pH of the solution is formulated with weakly alkaline about 7-9 with 1N NaOH. While stirring the inside of the reactor while maintaining the temperature at about 95 to 100 ℃ stirred for about 90 minutes to obtain a methylol (methylol) urea resin. At this time, by installing a high density to suppress the evaporation of odor and moisture during the reaction. Subsequently, the methylolated urea resin is cooled to room temperature, 1N acetic acid solution is added, the pH is adjusted to 4-7, and the methylene reaction is carried out. Thus prepared urea resin solution is used as a binder.

When urea resin is mixed with urea and formaldehyde, there are significant differences in physical properties depending on the reaction temperature and reaction time. In order for the urea resin to show the effect of fertilizer and to have properties as a caking agent, when the urea and formaldehyde are reacted, the temperature is about 90 to 110 ° C. and the acidity is appropriately controlled in the range of about 4 to 7 so that the monomethylol urea becomes The acidity should then be adjusted back to about 8-10 to maintain the methylene-2-urea to 5-methylene-6-urea. If the reaction proceeds further, it becomes ineffective as a slow-acting fertilizer, and it is difficult to use as a caking agent in the manufacture of a slow-release fertilizer.

Hereinafter, a process for preparing a slow-release fertilizer of the present invention will be described.

First, raw materials of general chemical fertilizers are stored in a hopper bin, and each raw material is weighed by an automatic weighing device and mixed in an automatic mixer. Thereafter, a urea resin solution having both the effects of the slow-fertilizing fertilizer and the effect of the adhesive prepared by the above method is added as a caking agent in a weight ratio of 5 to 30, preferably 5 to 15%, and stirred with a conventional chemical fertilizer raw material. do.

Verda (with gelatin 100), verda K (75-80 with gelatin), carin K (92 with gelatin), and Turin K (when preparing the caking component-formaldehyde solution) You can add adhesives such as 95 gelatin ingredients), Bertha cow (mixed gelatin ingredients with cow's favorite flavor supplements), and Accus Q (gelatin mixed with fish's favorite squid powder). have. In this case, the hole of the fertilizer particles is lost, so that the grain structure itself becomes harder, so that the fertilizer is sprayed on the field and is not easily dissolved even when water is absorbed. Therefore, the fertilizer effect can be sustained for a longer time.

The prepared caking adhesive solution is granulated by compression molding with a pan type, tablet type or pellet type, extrusion type, roller milling type compressor. Extrusion type rotates the helical screw and compresses the contents by press (force) to the ejecting mold. Roller milling inscribes the shape of two or more rolling rollers and compresses the gel contents through them. It can be produced by extrusion molding in a variety of polygonal shapes such as conical, triangular, square, etc. according to the mold of the roller. The general fertilizer particles are rounded so that when sprinkled on the field is easily rolled into the furrow, so that many fertilizers are lost, the fertilizer of the present invention is conical or polygonal shape, so even when sprayed on the field, less fertilizer loss.

The slow-release fertilizer granulated in the compression molding process is transferred to the coating process. In the coating process, the urea-formaldehyde resin solution is sprayed by the spray coating apparatus to coat the granulated-effective fertilizer and then transferred to the drying process. In the drying process, the coated slow fertilizer is dried while vibrating in order to prevent the coated slow fertilizer from sticking to each other by a dryer equipped with a vibrator, and then sent to a sorting process.

In the sorting step, only the slow-acting fertilizer having a diameter of 3 to 4 mm is sorted by the vibrating body and sent to the next step. The selected slow-release fertilizer is cooled and packed while being transferred to a conveyor belt after the coating, drying, and sorting process again.

Slow fertilizer according to the present invention prepared by the above method has a specific weight of 0.7 ~ 0.9g / cm ³ , the vertical compressive strength of 10.5 ~ 14.5Kg / cm ² , the horizontal compressive strength 16.11 ~ 26.85Kg / cm ² , The weight ratio of fertilizer was 0.94-0.97 g / cm ³ , and the strength was 1.94-5.86 Kg / cm ² .

Since conventional compound fertilizers are manufactured without compression molding, fertilizer particles are easily dissolved in water when fertilized in fields such as fields, or less than 30 days. Because of the high labor cost and high cost of fertilizers, fertilizers and fertilizers are excessively fertilized in the soil, which affects the acidity, temperature, and microorganisms of the land. However, because the slow-acting fertilizer according to the present invention was manufactured through compression molding and coating, it shows more than 10 times higher strength than the conventional compound fertilizer, so that even when water is absorbed, the fertilizer particles gradually melt and the fertilizer effect can be maintained for 90 days or more. In addition to reducing labor costs and reducing labor costs, the nutrients in the soil are continually supplied, which is environmentally friendly and can significantly prevent soil contamination due to fertilizer use. The slow-acting fertilizer prepared according to the present invention has no air hole in the particles, that is, the structure itself is hard, and since it is prepared by adding a binder and adhesives, the harder fertilizer effect can be further enhanced.

Hereinafter, the characteristics and effects of the slow-release fertilizer prepared according to the present invention will be described as an experimental example.

Experimental Example 1. Characteristics of Urea Resin

The properties of the caking urea resin prepared by mixing urea and formaldehyde are shown in Table 1 below.

Urea / Formaldehyde Molar Ratios (%) In building AI Actual weight Viscosity (mPa.s) All nitrogen Water soluble nitrogen Solids 1: 1 32.1 17.7 44.6 56.3 1.1657 9.5

※ AI (Activity Index)

As shown in Table 1, when urea and formaldehyde were reacted at a molar ratio of 1: 1, all nitrogen was 32.1%, water-soluble nitrogen was 17.7%, and a large amount of non-water-soluble nitrogen was present. It is 44.6% of the total, the specific gravity is 1.1657g / cm ³ (specific gravity 0.84g / cm ³ ), it can be seen that the viscosity has a characteristic of 9.5mPa.s.

Experimental Example 2 Fertilizer Elution Pattern Test in Water and Soil of Slow-Fertilizer Fertilizers According to the Present Invention

First, a test product of the slow-acting fertilizer according to the present invention when the urea resin was 10% by weight and 15% by weight was prepared.

(Underwater)

In order to determine the dissolution of fertilizer components in water of the slow-release fertilizer according to the present invention, 1 g of the test product was taken and placed in a 250 ml plastic bottle, and 100 ml of distilled water was put in a 30 ° C. constant temperature incubator. The dissolution rate was determined by analyzing the amount.

Nitrogen dissolution rate of the test product was eluted from 10th to 80th when urea resin was added 10% by weight as shown in Table 2, but when urea resin was added by weight ratio 15, 60th was eluted at 10th day. It was found that the dissolution rate of the slow-fertilizing fertilizer could be adjusted according to the amount added.

(Elution in soil)

In order to know the elution pattern of the slow-release fertilizer according to the present invention can be generally determined with the elution form in water, in order to know the elution form of the fertilizer in the actual soil, it is important to apply what the dissolution pattern in the soil tends to be important.

However, the elution pattern in the soil of the test product may show slightly different results depending on soil moisture, pH and soil microbial phase. In order to know the dissolution of fertilizer in soil, a certain amount of test product and a certain amount of sea sand were mixed, placed in a mesh bag, buried in soil, and collected at each time period to analyze the remaining amount of fertilizer in the mesh bag.

As shown in Table 3, when the urea resin is added in 10 weight ratios, the elution pattern of the test product is mainly used for leafy vegetables that require a large amount of fertilizer at the beginning. In the case of adding the urea resin by weight ratio 15, it was found that it was eluted at about 55 in the 10th day and about 60 in the 30th day.

As shown in the test results, the slow-release fertilizer according to the present invention, in which the urea resin was added in a weight ratio of 15, had a low dissolution rate, and the slow-release fertilizer according to the present invention, in which the urea resin was added in a weight ratio of 10, had a slightly higher dissolution rate. It was judged that this was. In other words, if the amount of urea resin is added, it is suitable for crops with a long fertilizer duration, and if the amount of urea resin is added, it is suitable for crops with short growth period such as cabbage and radish. .

Preparation Example.

① Formalin (37) 2.440 ② Element 1,056.2 to 1,811.1 ③ NaOH (24) 8.6 to 9.6 ④ CH ₃ COOH (25) 26 to 36 ⑤ NaOH (24) 26 to 36 ⑥ Element 208.8 to 358 ① Molar ratio = (0.5 ~ 1.5): 1② Al value = 22 ~ 25 (65) ③ Solid content = 65④ pH = 7.8 ~ 8.5⑤ Appearance = milky white

After joining ① shown in the above table, join ③ to adjust pH = 9.0 to 9.5, and then join ② and then raise the temperature to 90-95 ° C. with steam for 2 hours, then react ④ to join ④ to pH = 4.8 to 5.6. After adjusting for 15 ~ 20 minutes exothermic reaction (99 ℃), add ⑤ to adjust pH = 9.5 ~ 9.8, add ⑥ to keep for 20 minutes, and then cool. Vacuum dehydration at 65 ~ 70 ℃, cooled to 30 ℃ or less and transfer completed.

Example 1-4.

In the case of using the slow-release fertilizer in which the urea resin by weight 5 added to the slow-release fertilizer according to the present invention in Example 1, the urea resin by weight 10 added in Example 2 the case of using the slow-release fertilizer in which the urea resin by weight 7 In the case of using the fertilizer fertilizer with a weight ratio of 15 to the case of using the slow-fertilizer fertilizer was used in Example 4 when the fertilizer is not used (unfertilized) and conventional cultivation (common cultivation) Comparative test.

(Comparative test for pepper)

The test variety of red pepper is sun pepper and the fertilization amount is NP ₂ O5-K ₂ O = 24-20-23㎏ / 10a. Pavement size was 16.2㎡ per ward and three repeated egg masses were used. The treatments are five treatments, such as no-gu, conventional cultivation (using general chemical fertilizer), Example 1, Example 3, and Example 4. In the case of conventional cultivation, the cultivation of phosphate was carried out as a whole, the nitrogen as 50 and the remaining 50 as three times. Example was applied once at a total volume ratio.

Growth and quantity of pepper division Growth situation (September 30) Harvester Fruits and Vegetables Enemy and quantity Super long (cm) Liver diameter (mm) Raw weight (g / week) And number of provinces Total life (kg / 10a) Quantity index Movie sphere 76.4 9.2 14.5 16.9 696 49 Conventional cultivation 86.7 11.0 30.3 33.3 1,409 100 Example 1 84.1 10.9 33.9 27.8 1,254 89 Example 3 91.3 12.0 38.8 31.4 1,435 102 Example 4 89.7 11.2 35.5 33.8 1,435 102

As a result of the ineffectiveness test for red pepper as shown in Table 5, compared to the conventional cultivation using a general fertilizer, Example 1 was slightly shorter, but Examples 3 and 4 were larger than conventional materials. The total yield of the red fruit harvested four times was also slightly lower than the conventional cultivation Example 1, Example 3 and Example 4 was not significant, but slightly increased compared to the conventional cultivation. Therefore, it was judged that the addition of urea resin should be more than 10 by weight for crops that have a long growth such as red pepper.

Nutrients Absorption and Nutrient Utilization Rate of Harvest Peppers division Nutrient absorption amount (㎏ / 10a) Nutrient utilization rate (%) N P ₂ O ₅ K ₂ O N P ₂ O ₅ K ₂ O Movie sphere 3.2 0.8 3.6 - - - Conventional cultivation 11.5 2.6 16.2 34.3 18.5 55.0 Example 1 10.9 2.5 15.5 32.0 16.8 51.9 Example 3 12.6 2.9 18.5 39.2 21.3 64.8 Example 4 12.4 2.8 17.8 38.1 20.4 62.1

As a result of analyzing the nutrient uptake and nutrient utilization rate of red pepper by analyzing the harvest season pepper leaves, the nutrient uptake and nutrient utilization rate of Example 1 were somewhat lower than conventional cultivation as shown in Table 6, but in Examples 3 and 4, Absorption amount and nutrient utilization rate were high.

Experimental Example 5. Comparative Test for Various Crops

The effect of the slow-fertilizing fertilizer according to the present invention was carried out by different crops for each province according to the above examples.

In Gangwon-do, the fertilization rate of conventional cultivation is NP ₂ O5-K ₂ O = 32-20-27㎏ / 10a in Gyeonggi-do. NP ₂ O5-K ₂ O = 32-20-27 kg / 10a and NP ₂ O5-K ₂ O = 25-20-25 kg / 10a, respectively. The non-Gyeongbuk (large tray radish), Jeonbuk in Sesame (sesame Anshan), Chonnam in kind (Section kinds of black pearls) to the test in their practices cultivation sphere fertilizer Amount is 34 to 25, respectively NP ₂ O5-K ₂ O target -25, 8-4-9 and 25-17-22 kg / 10a.

Yield Response to Different Crops process Highland Cabbage (Gangwon-do) Chinese cabbage in spring Melon (Gyeongnam) Quantity Indices Quantity Indices Quantity Indices 3 elements - - 6,415 95 1,637 96 Conventional cultivation 2,903 100 6,737 100 1,708 100 Example 2 3,265 112 5,847 87 1,614 94 Example 3 3,039 105 6,445 96 1,719 101 process Radish (Gyeongbuk) Sesame (Jeonbuk) Gae (Jeonnam) Quantity Indices Quantity Indices Quantity Indices 3 elements - - 72.8 100 8,155 95 Conventional cultivation 13,153 100 - - 8,554 100 Example 2 12,793 97 78.6 108 - - Example 3 14,293 109 80.0 111 8,642 101 Example 4 - - - - 8,756 102 Gardening costs - - 77.2 106 - - Water Side Fertilizer - - 75.7 104 - -

The unit of yield is kg / 10a, and the index of sesame seeds is 100% of the three elements total ratio, and the crops except sesame seeds are 100% of conventional cultivation. In addition, horticulture clothing ratio is NP ₂ O5-K ₂ O = 11-10-10kg / 10a, and water-side fertilizer is a slow-acting fertilizer in which some coating elements are mixed with latex and NP ₂ O5-K ₂ O = 18-12-14 kg / 10a was used.

As a result of Table 7, the highland cabbage of Gangwon-do and the sesame of Jeonbuk tended to increase somewhat in Example 2 and Example 3, and the radish of Gyeongbuk in Example 3, and the cabbage melon of Gyeongnam and the pepper of Jeonnam It was judged that the effect of the slow-fertilizer was affected by temperature because the effect of the slow-fertilizer was not great.

As described above, the slow-fertilizing fertilizer according to the present invention can provide fertilizers only once, thus reducing labor and reducing labor costs, thus reducing the production cost of agricultural products, and supplying them to consumers at low prices. Because of the high utilization of fertilizer, there is little loss of fertilizer, which is environmentally friendly and many other beneficial fertilizer effects can be expected.

Claims (7)

A process for producing a slow-release fertilizer characterized by mixing and stirring a caking-based urea-formaldehyde resin solution in which a formaldehyde and urea are mixed at a molar ratio of (0.5 to 1.5): 1 with a conventional chemical fertilizer, followed by compression molding and coating. The method of claim 1, Method for producing a slow-acting fertilizer characterized in that the addition of the caking resin solution in 5 to 30 weight. The method of claim 1, The urea-formaldehyde is methylene-diurea, trimethylene-tetraurea, pentamethylene-hexaurea, methylenebis-acetylurea, monomethyloleurea, monomethylolureamethylethyl, monomethylolurea-dimethylether, dimethyl A slow-acting fertilizer characterized by being urea dimethyl ether, dimethylurea di-N-propylether, dimethylolurea di-N-amyl ether, dimethylolurea dibenzylether, dimethylolurea diethylthioether, or tetramethylolurea. Manufacturing method. The method of claim 1, The compression molding is a pan type, pellet type, tablet type, extrusion type or roller milling method for producing a slow-acting fertilizer characterized in that. The method of claim 1, The coating process is a method for producing a slow-acting fertilizer in which the caking urea-formaldehyde resin solution is carried out by spray coating. The method of claim 1, Method for producing a slow-acting fertilizer characterized in that the adhesive agent such as Verda, Verda K, Karin K, Turin K, Berta cow, or Accus cue is added to the caking urea solution. A slow-release fertilizer having a specific gravity of 0.7 to 0.9 g / cm ³ , a vertical compressive strength of 10.5 to 14.5 kg / cm ² , and a horizontal compressive strength of 16.11 to 26.85 kg / cm ² prepared by the method of claim ¹ .