JPH0339037B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to NPK-containing granular fertilizer coated with alkyd resin. Fertilizers are, as is well known, substances added to useful plants to promote growth, increase yield, or improve quality. All known solid fertilizers supply nutrients to plants via the soil or substrate solution, depending on their dissolution rate. Known techniques control the rate of dissolution so that nutrients can be effluxed uniformly over a selectable period of time from the time of administration, depending on the composition of the fertilizer. However, all these fertilizers have in common that the onset of nutrient release cannot be controlled, with fast-release fertilizers immediately releasing the entire amount of nutrients and slow-release fertilizers releasing only a partial amount. Increasing the availability and therefore effectiveness of fertilizers from physiological, ecological and economic points of view, reducing phytotoxicity and leaching of fertilizers with one high total application rate and therefore with the lowest possible fertilizer application costs. It is desirable and necessary to avoid or at least significantly reduce environmental pollution due to losses. The object of the invention is therefore to obtain a fertilizer which supplies nutrients only at the desired time and in the desired amount. This problem is solved according to the invention in the NPK-containing granular fertilizer coated with alkyd resin, in which the alkyd resin layer contains a substance from the group of iron palmitate, polyvinyl alcohol condensate and methylpolysiloxane to control the release of nutrients. The problem can be solved by using modified fertilizers. A special embodiment of this fertilizer is that: the fertilizer is a fertilizer from the group of mineral mononutrient fertilizers, mineral multinutrient fertilizers, organic fertilizers, micronutrients, plant treatments or mutual combinations thereof. ; The fertilizer is a fertilizer powder, a crystalline fertilizer, a granulated fertilizer,
Present as granulated coated fertilizer, fertilizer bar, encapsulated fertilizer solution or encapsulated fertilizer suspension; the fertilizer contains as nutrients carbon, oxygen, nitrogen, phosphorus, potassium, magnesium, calcium, sulfur, iron, manganese, copper, Contains zinc, chlorine, boron, molybdenum, sodium, silicon and/or cobalt in the form of compounds;
coated with a water-repellent agent from the group of quaternary ammonium compounds, urea derivatives, resins modified with fatty acids, silicones and/or penfluorinated organic compounds; the water-repellent agent is iron palmitate; water-wetting nutrients coated with a water-repellent or water-swelling agent from the group of polymers having groups; the water-wettable groups are hydroxyl, carboxyl,
are alkyl esters, cyanogen, chloro or fluoro groups; the poorly water-soluble or water-swelling agent is preferably polyvinyl alcohol with a residual acetyl content of 10%; coated with a poorly water-soluble agent; the poorly water-soluble agent is iron phosphate or calcium phosphate; the nutrient is coated with a poorly water-soluble or water-swelling agent from the group of polymers or inorganic compounds having water-wet groups; and paraffin, wax, metal soap, quaternary ammonium compounds, urea derivatives,
coated with a water-repellent agent from the group of fatty acid ^- modified resins, silicones and/or ^{perfluorinated} organic compounds; coated with a film thickness of 10 ^-6 m to 2.10 ^-3 m; an agent that is poorly soluble in water or swells in water absorbs nutrients in a film thickness of 10 ^-6 m to ^{10 -2} m, preferably 5.10 ^-5 m to 2・10 ^-3
coated with m; the substance is incorporated into the alkyd resin layer; the substance is applied onto the alkyd resin layer. The fertilizer according to the invention surprisingly has a time-delayed nutrient release, the onset of which can be controlled depending on the desired purpose, so that the nutrient efflux can be advantageously adjusted from 1 day to 2 years. will begin only after a delay time of 30 to 180 days. This controlled nutrient release provides numerous benefits not achieved through the use of known fertilizers. By adjusting the nutrient release to the maximum and zero requirements of the plants, fertilization can be carried out in relation to demand, for example, which is not possible with known fertilizers. This makes it possible to optimally satisfy the different nutritional requirements of the plants during the cultivation period, so that damage to the plants due to over-fertilization during periods of high plant sensitivity or insufficient amounts of nutrients during periods of maximum demand can be achieved. Insufficient growth due to this can be advantageously avoided. Furthermore, the controllable release of the nutrient supply using the fertilizer according to the invention has the advantage of unlocking the productive potential of plants even under climatically unfavorable conditions or on slightly soil soils, which was previously closed. This opens the way to highly efficient fertilization. Furthermore, the controllable release of the nutrient flux using the fertilizer according to the invention allows the varying requirements regarding the nutrient type and its concentration of a particular cultivation to be optimally met by the total amount of fertilizer applied once at the time of sowing or potting. This opens up the possibility of omitting top-dressing, which is dangerous and ineffective when adjusting the organic expiration date of fertilizers. Moreover, the controllable release of nutrients with the fertilizer according to the invention gives the possibility of adding fertilizer to the substrate long before application, without having to take into account the already active salt content, which is high at the beginning of application. Nomo salt is activated only at the beginning of use by irrigating the substrate, thereby avoiding salt shock or salt damage. The fertilizers of the present invention may be present as mineral mononutrient fertilizers, mineral multinutrient fertilizers, organic-mineral fertilizers, organic fertilizers, micronutrients, and combinations of the aforementioned components. Pretreatment fertilizers include, for example, fertilizers with a prolonged release of plant nutrients, such as poorly soluble salts, polymeric nutrient compounds, and chemically or physically bound nutrients in natural and synthetic carriers. The following nutrients can be mentioned. The fertilizer according to the present invention is produced by a method known per se.
For example, the fertilizer whose nutrient release is to be influenced according to the invention is charged into a device suitable for the particular treatment method, for example a rotating drum or a granulation pan or a fluidized bed device, and the treatment agent is applied until the fertilizer is completely and thoroughly processed. The fertilizer to be uniformly coated with the desired film or the treatment agent is introduced into a suitable device, for example a rotating drum or a granulation pan, and whose nutrient release is to be influenced according to the invention. The fertilizer is introduced in such a way that it is completely and sufficiently evenly coated with the desired film thickness. The film should be applied at a film thickness of 10 ^-8 m to ^{10 -2} m, especially 1.
Perform at a distance of 10 ^-6 m to 2.10 ^-3 m. The treatment agents can be applied as single components themselves, as solutions or emulsions, and can likewise be combined in multicomponent systems. Next, the present invention will be explained in detail with reference to examples. Example 1: Nutrient composition 13/13/21, particle size spectrum
237.5 g of NPK-structured granules having a diameter of 2.0-4.0 mm are heated to 100-110 DEG C. in a rotating drum with hot air. The granules were treated with 9 parts of a binder based on oil-modified alkyd resins with 1 part of iron palmitate in a solvent mixture of 1 part of benzene and 2 parts of xylene with a boiling point of 130-220°C, with a continuous supply of hot air. 26%−
A total of 48 g of suspension is added such that the dosing rate and drying rate are the same. After finishing the treatment, the granules are gradually cooled to room temperature. Example 2 Particle size spectrum 3.0-5.0mm, nutritional composition
18/4.5/9/MgO0.9/Fe0.1, 50%-
NPK manufactured using 100g of alkyd resin solution
- 475 g of granules are heated in hot air in a sugar coating drum for 50~
Heat to 60℃. The granules were continuously placed in hot air (500
/min) to 10% - aqueous polyvinyl alcohol solution (residual acetyl content approx. 10%, viscosity approx. 35 mm at 20°C)
pas) Add the total amount of 250g so that the metering speed and drying speed are the same. After completion of treatment, slowly cool to room temperature. Example 3 Particle size spectrum 3.0-5.0mm, nutritional composition
18/4.5/9MgO0.9/Fe0.1, NPK-granules 383g
and 425 g of fertilizer prepared from 85 g of 50% alkyd resin solution are heated to 50-60 DEG C. with hot air in a sugar coating drum with perforated plates. A 10%-aqueous polyvinyl alcohol solution (residual acetyl content approximately 10%, viscosity 35 mm at 20 °C) is applied to the granules under a continuous flow of hot air.
pas) Gradually add the total amount of 500g at the same metering speed and drying speed. After applying the granules to 110~
25 g of the precrosslinked methylsiloxane/curing agent mixture heated to 120 DEG C. are added in such a way that the metering and curing time coincide. After the treatment is completed, gradually cool to room temperature. The following examples describe the use of fertilizers according to the invention and a comparison of their effectiveness with known materials. Example 4 Determination of the nutrient release course of granular fertilizers in water over time by continuously measuring the conductivity of dissolved salts that accumulate in water

【table】

[Table] Example 5 Fertilizer with a depressiv action, once mixed into the substrate before sowing of the sow, was applied to the substrate by measuring the yield of each cutting of the dry weight of the soybean over a period of 80 days after fertilization. Determination of the nutrient release course over time of granular fertilizers (in the table, 100% of substrates with a good, natural nutrient supply without fertilizer mixtures with continuous action)
)

【table】

Claims (1)

Claims: 1. characterized in that the alkyd resin layer is modified with substances from the group of iron palmitate, polyvinyl alcohol condensates and methylpolysiloxanes in order to control the release of nutrients, NPK-containing granular fertilizer coated with alkyd resin. 2. The fertilizer according to claim 1, wherein the substance is blended in an alkyd resin layer. 3. The fertilizer according to claim 1, wherein the substance is applied on an alkyd resin layer.