RU2838000C2 - Hydrophobic coatings for improvement of parameters of physical quality of fertilizers - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: fertilizer contains granules with a coating for moisture control, each of the coated granules includes: a fertilizer granule base; and a moisture control coating applied to the fertilizer granule base, where the coating includes a hydrophobic material component and a roughening component, where the roughening component contains particles providing surface micro-roughness on the outermost surface of the coated granules. A method of producing coated fertilizer granules for controlling moisture absorption, where the method involves: using fertilizer granules; and coating the fertilizer granules with a moisture absorption control material containing a hydrophobic material and a roughening component, where the roughening component contains particles which provide surface micro-roughness on the outermost surface of the coated granules.

EFFECT: inventions make it possible to develop a coating which reduces tendency to caking of water-soluble fertilizers.

30 cl, 11 dwg, 5 ex

Description

RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 62/793,582, filed January 17, 2019, which is incorporated herein by reference in its entirety.

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

Embodiments of the present invention relate to a hydrophobic or superhydrophobic coating for reducing agglomeration (caking), decomposition (breakdown) and dust formation of granular fertilizers during storage, transportation and application. More specifically, the present invention describes a rough coating or surface treatment with a low surface energy compound that minimizes the effect of cyclic changes in humidity and temperature of the fertilizer to reduce agglomeration, decomposition and dust formation. In embodiments, the coating can be applied to the fertilizers in a single step and can also contain one or more micronutrients and/or secondary nutrients, and provide flowability.

LEVEL OF TECHNOLOGY

Many agricultural fertilizers are produced by granulation followed by drying and cooling before storage for long periods of time before application to the soil. A characteristic difficulty during this conventional storage is the strong tendency of much of the fertilizer to form lumps and agglomerates. The formation of hard lumps and agglomerates is usually a consequence of the cyclic changes in humidity as it passes from day to night temperatures. As humidity increases, moisture condenses from the air and/or moisture escapes from the granules and the fertilizer begins to dissolve. As humidity and temperature decrease during recrystallization, crystalline bridges form salt bridges that bind the granules together. These lumps and agglomerates are formed in most fertilizer storage facilities.

Fertilizer that has been agglomerated is more likely to form dust when packaged or transported due to the shifting of these crystals. This makes the fertilizer significantly more difficult to use and distribute on the ground, as the dust tends to become airborne and its application is difficult to control, ultimately resulting in uneven distribution of the nutrient and possible health hazards to users. If the clumps of fertilizer are hard and not damaged during transport, they can cause blockages in the distribution equipment, which also results in uneven distribution of the nutrient and wear on the equipment.

The critical relative humidity, or CRH, at which most fertilizers absorb moisture from the air and undergo physical decomposition due to caking is 60 to 75% relative humidity (at 35°C or 95°F). At this humidity, moisture from the air is deposited on the fertilizer and the process of surface dissolution begins. When fertilizers with different CRHs are mixed, the CRH of the mixture changes and affects the component with the lowest CRH, which can make the mixture susceptible to caking under normal storage conditions. This can significantly limit the use of possible mixing components and storage capabilities.

Coating granular fertilizers reduces the possibility of decomposition. However, many of the hydrophobic coatings used for fertilizers are expensive, making them unsuitable for industrial use over large areas and are used only in more profitable areas such as lawn and golf course treatment.

Steps have been taken to incorporate hydrophobic coatings into fertilizers to significantly slow the release of nutrients from the fertilizers, thereby producing controlled or delayed release fertilizers, such as those described in U.S. Patent No. 7,452,399, entitled "Coating for Fertilizer," U.S. Patent No. 4,857,098, entitled "Sulfur-Coated Fertilizer Granules and Process of Making the Same," and U.S. application Ser. No. 14/351,560, entitled "Encapsulated Nitrogen Fertilizer Composition with Fire-Extinguishing and Fire-Spreading Preventing Option Corresponding Manufacture Process and Application Process," all of which are herein incorporated by reference in their entireties. However, these coatings do not necessarily result in reduced caking and dust formation. Furthermore, these types of coatings are often formed from synthetic polymers for which the effects of long-term residence in soil have not been studied. Natural products such as waxes and oils are sometimes used for their ability to prevent caking, such as those described in U.S. Patent No. 6,355,083B1, entitled "Dust Control Composition for Fertilizer and Method of Treatment of Fertilizer," which is incorporated herein by reference in its entirety, but they generally do not provide the required long-term storage benefit of the fertilizer. Accordingly, these coatings can result in a significant reduction in the shelf life of the fertilizer and are often difficult to apply uniformly to uneven surfaces.

Inert inorganic particles have been included in some coatings as fillers in an attempt to close the pores of the fertilizer macrogranules, slow down the penetration of water and therefore the release of the nutrient from the product, as discussed, for example, in PCT Application Publication No. WO 2000/076649, which is incorporated herein by reference in its entirety. To control and slow down the release of the nutrient using fillers, up to 20% by weight of the coating is necessary, as described, for example, in European Patent Application Publication No. EP 0 976 699, and often the inclusion of other hydrophobic compounds such as amines is necessary to further slow down dissolution, as described in French Patent Application Publication No. FR 2155883A2, both of which are incorporated herein by reference in their entireties; however, this is not necessary for an anti-caking coating.

What is needed is an environmentally friendly and inexpensive coating that reduces the caking tendency of water-soluble fertilizers, particularly those with irregular angular particles such as compacted potassium chloride, which are otherwise difficult to coat uniformly.

ESSENCE OF THE INVENTION

Embodiments of the present invention generally relate to a hydrophobic or superhydrophobic coating of fertilizer granules. A hydrophobic coating is one for which the contact angle is 90 degrees or more when measured from the surface, and a superhydrophobic coating is one for which the contact angle is 140 degrees or more. For simplicity, "hydrophobic" is used hereinafter to describe a hydrophobic or superhydrophobic state. The hydrophobic coatings of embodiments include a particulate roughening additive and a low surface energy hydrophobic component such as a wax coating, a wax emulsion, or an oil treatment agent. In embodiments of the present invention, one or more additives to the hydrophobic coating result in a surface roughness on the surface of the fertilizer in the order of micrometers, which in itself may, but does not necessarily, increase the hydrophobicity and/or nutritional value of the fertilizer. The hydrophobic coating on the fertilizer granule is used to protect the water-soluble fertilizer granules from absorbing moisture.

In one embodiment of the present invention, the hydrophobic coating material is in a liquid or molten state. Then, one or more additives are introduced into the molten or liquid hydrophobic coating material. The hydrophobic coating material is sprayed or roller-coated onto the surface of a fertilizer granule base containing one or more primary nutrients, such as phosphorus-based, nitrogen-based and/or potassium-based fertilizers (collectively referred to as "NPK fertilizers"). In embodiments, suitable fertilizer granules may comprise, for example, nitrogen-containing fertilizers such as nitrates and ureas, potassium-containing fertilizers such as potash, including potassium chloride (MOP) or potassium sulfate (SOP), phosphorus-containing fertilizers such as phosphate fertilizers, including ammonium phosphates, such as monoammonium phosphate (MAP) or diammonium phosphate (DAP), calcium phosphate-based fertilizers, including single superphosphate (SSP) or triple superphosphate (TSP), potassium phosphates, calcium phosphates, or any combination thereof. Additives to the hydrophobic coating impart roughness, which leads to a decrease in the contact angle between the surface and water droplets, which leads to water running off the surface and thereby prevents or reduces water absorption.

In another embodiment of the present invention, a roughening material is first applied to the fertilizer granules. In this embodiment, the roughening additive in the form of particles is added first, for example, by conventional coating techniques, such as spray coating with the application of one or more continuous or non-continuous coatings on the base of the fertilizer granule. After the roughening compound in the form of particles is applied to the granule, a low surface energy hydrophobic material, such as wax and/or oil, is added, and one or more continuous or non-continuous coatings are applied to the base of the coated fertilizer granule. The time between the application of the roughening compound and the coating may vary depending on the process design.

In a third embodiment, the surface roughness is the result of physical processing, such as mechanical abrasion of the surface or intentional roughening of the surface during the manufacture of the granule base. One example of this is the control of the degree of crystallization and the degree of annealing of the granule base to provide the desired surface roughness. Then, only the application of a low-surface-energy superhydrophobic coating with or without additives may be required to provide the surface roughness.

In another alternative embodiment, a hydrophobic coating with or without roughening additives is applied to the base of the fertilizer granule and structured during application or after subsequent application to the granule. For example, the application of a microrelief can be carried out using the coating while still in a liquid, molten or other liquid state to form a micro-rough surface structure.

The above summary of the invention is not intended to describe each illustrated embodiment or each embodiment of the present invention. The full description below presents more preferred embodiments.

BRIEF DESCRIPTION OF DRAWINGS

The subject matter of the invention can be more fully understood by reference to the following detailed description of various embodiments together with the accompanying drawings, in which:

Fig. 1 is a cross-sectional view of a fertilizer granule comprising a superhydrophobic coating for one embodiment of the present invention;

Fig. 2 shows a cross-section of a fertilizer granule containing a superhydrophobic coating for an alternative embodiment of the present invention;

Fig. 3 is a perspective view of a roughened fertilizer for one embodiment of the present invention;

Fig. 4 shows a comparison of fertilizer granules showing the effect of different fertilizer coatings on the caking tendency of the fertilizer for embodiments of the present invention;

Fig. 5 is a chart comparing moisture absorption by fertilizer for embodiments of the present invention;

Fig. 6A and 6B illustrate a comparison of moisture repellency and wicking for embodiments of the present invention;

Fig. 7 is a diagram comparing the caking tendency of fertilizer for embodiments of the present invention;

Fig. 8 is a chart comparing the abrasion resistance of coated fertilizers for embodiments of the present invention;

Fig. 9 is a chart comparing dust generation by coated fertilizers for embodiments of the present invention;

Fig. 10 is a chart comparing the degradation of coated fertilizers for embodiments of the present invention.

Although various modifications can be made to the various embodiments, the alternative forms described are shown by way of example in the drawings and described in detail. However, it should be understood that the present invention is not limited to the specific embodiments described as claimed in the invention. On the contrary, the present invention includes all modifications, equivalents and alternatives that fall within the scope of the subject matter defined in the claims.

DETAILED DESCRIPTION OF DRAWINGS

In one embodiment of the present invention, shown in Fig. 1, a hydrophobic coated fertilizer granule 100 may include a portion of a fertilizer base 102 and a hydrophobic coating material 103, a particulate roughening additive or component 104, and a low surface energy hydrophobic material 106 coated or otherwise applied to at least a portion of the fertilizer 102.

In embodiments, the fertilizer portion 102 may comprise any suitable fertilizer, such as, for example, nitrates, ureas, potash, phosphate fertilizers such as monoammonium phosphate (MAP), diammonium phosphate (DAP), single superphosphate, triple superphosphate, potassium phosphates, calcium phosphates, or combinations thereof.

In embodiments, the hydrophobic coating material 103 may comprise a dispersion, emulsion, suspension or mixture of a roughening additive in the form of solid particles 104 or a roughening agent in a low surface energy material 106. In embodiments, this roughening additive 104 may comprise silicates, sand, rock phosphate, calcium carbonate, gypsum, micronutrients such as zinc, manganese, iron, copper, molybdenum, boron, chloride, cobalt, sodium, sulfur in the form of sulfate, elemental sulfur, stearates including, for example, but not limited to, sodium stearate and zinc stearate, fatty acids such as stearic acid, a metal salt of a fatty acid, dusty potassium carbonate or any combination thereof. In alternative embodiments, any crystalline or amorphous compound in solid particle form with a solubility lower than that of the granule base may be used. In one embodiment, the coating 103 comprises from about 0.01 wt.% to about 10 wt.%, more preferably from about 0.01 wt.% to about 5 wt.%, and even more preferably from about 0.1 wt.% to about 1.0 wt.% of a crystalline or amorphous roughening additive in solid particle form, based on the total weight of the granule. These additives may or may not themselves be hydrophobic. The roughening additive 104 may be dispersed, emulsified, or otherwise suspended in the hydrophobic material 106.

In embodiments, the low surface energy hydrophobic material 106 may comprise candelilla wax, beeswax, carnauba wax, food-recovered waxes, wax emulsions, or combinations thereof. In other embodiments, the hydrophobic material 106 may be any plant-based or chemical-based wax with a melting point of from 50°C to about 105°C (from about 122°F to about 221°F). In another embodiment, the hydrophobic material 106 may be a wax obtained in the petrochemical industry, such as crude paraffin, paraffin wax, microcrystalline waxes, or combinations of oils and waxes. A combination of natural and synthetic waxes with or without any oil can be applied to form a hydrophobic or superhydrophobic coating.

In another embodiment, the hydrophobic material 106 consists of any suitable natural, mineral or synthetic oil. The oils can be any suitable natural, mineral or synthetic oil, such as white petrolatum, but preferably vegetable oil, including canola oil, sunflower oil, soybean oil, castor oil, linseed oil, olive oil or modified vegetable oils. Other hydrophobic fatty acids, such as stearic acid, can also be used. In embodiments, a combination of any wax, oil or fatty acids can be used. In embodiments, the coating containing a hydrophobic wax, an oil additive or a mixture of a wax and an oil additive is from about 0.01 to about 10% based on the total weight of the fertilizer granule, more preferably from about 0.1 to about 5 wt.%, and more preferably from about 0.5 to about 2.0 wt.% based on the total weight of the fertilizer granule. The thin coating provides hydrophobicity or superhydrophobicity and also provides the advantage of controlling dust formation without inhibiting the release of fertilizer nutrients after application to the soil.

In one embodiment, according to Fig. 1, a method for forming a coated fertilizer granule 100 includes combining a predetermined amount of a roughening agent in the form of solid particles 104 with a predetermined amount of a hydrophobic material 106 to form a superhydrophobic coating material for coating a shaped fertilizer granule. In this embodiment, the hydrophobic coating material 106 can be in liquid, solid or melt form and can be applied by spraying, rollers or any suitable coating technique to form a continuous or non-continuous coating on a shaped base of the fertilizer granule 102 to form a number of coated fertilizer granules 100. The granules are then dried or cooled.

In one embodiment, according to Fig. 2, the roughening agent in the form of solid particles 204 can be applied to the surfaces of the fertilizer granule 202 before the low surface energy material 206 is applied to the fertilizer granule 202. In this embodiment, the roughening agent in the form of solid particles 204 can be applied as a liquid, a solid or a melt and can be applied by spraying, rollers or any suitable coating technique to form a continuous or non-continuous coating on the formed fertilizer granule 202 to form a number of coated fertilizer granules. In one embodiment, the finely or amorphously coated granules are then coated with a low surface energy material 206. The low surface energy material 206 may be in liquid, solid, emulsified or melted form and may be applied by spraying, roller coating or any suitable coating technique to form a continuous or non-continuous coating on the coated crystalline fertilizer granules to form a number of coated fertilizer granules 200. The granules are then dried or cooled.

In one embodiment of the present invention, shown in Figs. 1 and 2, crystalline or amorphous additives in the form of solid particles provide a micrometer-scale roughness of the surface of the fertilizer 104, 204. In this embodiment, roughening of the fertilizer granule can be carried out using various previously described crystalline or amorphous additives in the form of solid particles. The additives can have a particle size of from about 50 nm to about 250 μm. In the most preferred embodiment, these materials can have a size of from about 10 μm to about 150 μm. In other embodiments, the size of the additives is greater than 150 μm. In the embodiments of the present invention shown in Figs. 3, the micrometer scale of the surface roughness results in the fact that the surface areas occupied by the deposited water droplets and the fertilizer granule 306 are minimal compared to the case of no coating 302. The roughness results in the fact that the water droplets remain spherical, so that the air trapped between the fertilizer 306 and the water droplets prevents water from penetrating into the fertilizer granule. These coatings can also be applied to granules that are heated to a temperature above the ambient temperature to promote wetting of the surface of the hydrophobic low surface energy coating and optimize the uniformity of the coating.

In embodiments, the particulate roughening compound and low surface energy hydrophobic additives impart a roughness that increases the hydrophobicity of the coating with minimal impact on the flowability, sprayability, or application of the coating. In the most preferred embodiments, the coating should be substantially degradable after application to the soil so that the fertilizer nutrients are readily released into the soil.

The following examples illustrate specific embodiments of the present invention. Each example utilizes a SPEX Mixer Mill 8000M with a damped motor. In some examples, the mixing rollers operate with an oscillating motion of 5.9 cm back and forth and 2.5 cm sideways at a rate of 1060 cycles/min.

Typical materials were prepared in a batch mode by first loading uncoated MOP granules, then adding the appropriate roughening materials in the form of solid particles, mixing for 1 min, then heating together with the low surface energy material, and further mixing while naturally cooling to ambient temperature.

Example 1: MOP, MOP+wax, and MOP+wax and roughening agent in solid particle form

The tracking of uncoated MOP was compared to that of wax-coated MOP and wax-coated MOP with a roughening material. The test conditions were as follows: 4 g samples were heated at 35°C (95°F) with 1 kg of mass at 80% relative humidity for 7 days.

The caking tendency of MOP is relatively high due to the existing particle size distribution and the angular shape of the product. In bulk storage, caking results in a crust on the MOP mass under natural moisture cycles. As shown in Fig. 4, MOP coated with finely ground phosphate rock and candelilla wax exhibits significantly less caking than MOP without surface treatment and MOP with wax alone.

Example 2: Moisture absorption of MOP with wax and roughening material

The moisture uptake (weight gain, %) at 75% and 80% relative humidity of the 1.5% candelilla wax coated fertilizers was compared with a range of roughening material contents (Fig. 5). The roughening materials used in this example included phosphate rock, bentonite clay, calcium carbonate (CaCO₃), diatomite, elemental sulfur (elemental S), apatite nanoparticles (Ca₅(PO₄)₃(F, Cl,OH)) produced by SKY Spring Nanoparticles Inc, apatite nanoparticles produced by MK Nano, dolomite (CaCO₃⋅MgCO₃), gypsum (CaSO₄,2H₂O) and zinc oxide (ZnO). Roughening materials were added in amounts ranging from 0.1% (elemental S) to 2.4% (dolomite). Moisture absorption was determined after treatment for 3 h at 75 and 80% relative humidity (25°C).

As shown in Fig. 5, at 80% RH, the fertilizer composition coated with candelilla wax and rock phosphate had the lowest moisture absorption.

Example 3: Caking tendency of MOP, MOP+ZnO in an emulsion of wax and roughening Zn stearate with candelilla wax

In this example, MOP particles were coated with a 1.5 wt% wax emulsion on 0.5 wt% Zn fertilizer from ZnO or a Zn stearate/candelilla wax coating. Figures 6A and 6B show that after 15 days at 80% RH, moisture is released from the coated fertilizer composition (see Figure 6A) but is absorbed by the uncoated MOP particles (see Figure 6B). The force required to break up ~3 g of caked fertilizer samples after treatment at 80% RH and 22°C for 30 days, followed by overnight drying at 40°C and equilibration to ambient temperature are shown in Figure 7. As shown, the ZnO and Zn stearate roughening materials in the wax emulsion or melts significantly reduced the cake tendency of the uncoated MOP.

Example 4: Abrasion resistance versus time for MOP and MOP coated with ZnO and wax emulsion using different wax ratios and sources

The percent degradation was calculated as the proportion in wt.% of particles <250 μm remaining after processing a 10 g sample (+1-3.35 mm) for 30 s in a Spex-mixer/Mill (8000M); the study was repeated three times. Compared to the uncoated sample, the % degradation for these coatings was reduced by a factor of ~10, as shown in Fig. 8.

Example 5: Product decomposition and dust formation

In Figs. 9 and 10, product degradation and dust formation were compared for samples with a moisture control coating described in the present invention and an uncoated MOP. In the figures, samples #1A-C and #2-C were coated with a roughening sodium stearate coating at a rate of 2 pounds of stearate per ton of fertilizer granules and a hydrophobic coating formed from VM160 petroleum oil with 5% amine at a rate of 3 pounds of coating per ton of granules. Sample #3 was coated with a roughening and hydrophobic coating of the same composition, but the amount of roughening material was increased to 3.5 pounds per ton. As shown in the figures, dust formation and percent failure for the coated samples were significantly reduced compared to the original uncoated sample.

The present invention may be embodied in other specific forms without departing from its essential features; therefore, the illustrated embodiments are to be considered as illustrative and not restrictive in all respects. The claims ensure the adequacy of the present application for establishing priority abroad and for no other purposes.

The present invention describes various embodiments of systems, devices and methods. These embodiments are provided by way of example only and do not limit the scope of the claimed invention. In addition, it should be understood that various features of the described embodiments can be combined in various ways to obtain numerous additional embodiments. In addition, although various materials, sizes, shapes, configurations and positions, etc. are described for use with the disclosed embodiments, others than those disclosed can be used without departing from the scope of the claimed invention.

Those skilled in the relevant art will understand that the subject matter of the invention may include fewer features than those indicated in the individual embodiment described above. The embodiments described in the present invention are not an exhaustive representation of the ways in which its various features can be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, different embodiments may include a combination of different individual features selected from the individual embodiments, as will be understood by those of ordinary skill in the art. Furthermore, elements described in one embodiment may be used in other embodiments even if they are not described in such embodiments, unless otherwise indicated.

Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments may also include a combination of a dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are provided in the present invention unless it is indicated that a specific combination is not intended.

Any documents incorporated by reference herein above are limited so that no matter is included that is inconsistent with the express disclosure herein. Any incorporation by reference of the documents above is further limited so that claims included in those documents are not incorporated by reference. Any incorporation by reference of the documents above is further limited so that any definitions given in the documents are not incorporated by reference unless expressly stated otherwise.

For the purposes of interpreting the claims, it is expressly understood that the provisions of 35 U.S.C. § 112(f) do not apply unless the claims specifically use the terms "means for" or "step for."

Claims (38)

1. A fertilizer containing coated granules for moisture regulation, each of the coated granules comprising: the basis of the fertilizer granule; and a moisture control coating applied to a base of a fertilizer granule, wherein the coating comprises a hydrophobic material component and a roughening component, wherein the roughening component comprises particles that provide a micro-roughness of the surface on the outermost surface of the coated granules. 2. The fertilizer according to item 1, wherein the roughening component has a solubility lower than the base of the fertilizer granule. 3. The fertilizer according to claim 1 or 2, wherein the roughening component comprises solid particles with a particle size in the range from 10 μm to 150 μm. 4. The fertilizer of any preceding claim, wherein the roughening component is selected from the group consisting of the following: silicates, sand, phosphate rock, calcium carbonate, gypsum, zinc, manganese, iron, copper, molybdenum, boron, chloride, cobalt, sodium, sulfur in the form of sulfate, elemental sulfur, zinc stearate, sodium stearate, stearic acid, powdered potassium carbonate, and combinations thereof. 5. A fertiliser according to any preceding claim, wherein the roughening component is present in an amount equal to from 0.01% by weight to 10% by weight, based on the total weight of the granule. 6. The fertilizer according to item 5, wherein the roughening component is contained in an amount equal to from 0.1 wt.% to 1.0 wt.% based on the total mass of the granule. 7. A fertilizer according to any preceding claim, wherein the hydrophobic material component comprises a wax, an oil, a fatty acid, or a combination thereof. 8. The fertilizer of claim 7, wherein the hydrophobic material component comprises a wax selected from the group consisting of candelilla wax, beeswax, carnauba wax, vegetable wax, paraffin, crude paraffin, microcrystalline wax, an emulsion of wax and oil, and combinations thereof. 9. The fertilizer of claim 7, wherein the hydrophobic material component comprises an oil selected from the group consisting of white liquid paraffin, petroleum oil, canola oil, sunflower oil, soybean oil, castor oil, linseed oil, olive oil, modified vegetable oils, and combinations thereof. 10. A fertilizer according to any preceding claim, wherein the hydrophobic material is present in an amount equal to from 0.01% to 10% based on the total weight of the fertilizer granules. 11. The fertilizer according to claim 10, wherein the hydrophobic material is contained in an amount equal to 0.5 to 2.0 wt.% based on the total mass of the fertilizer granules. 12. The fertilizer of any preceding claim, wherein the fertilizer granule base is selected from the group consisting of the following: nitrates, ureas, potassium chloride, potassium sulfate, monoammonium phosphate (MAP), diammonium phosphate (DAP), single superphosphate, triple superphosphate, potassium phosphates, calcium phosphates, and combinations thereof. 13. The fertilizer of claim 1, wherein the moisture control coating comprises a wax emulsion containing ZnO. 14. The fertilizer of claim 1, wherein the moisture control coating comprises sodium stearate and/or zinc stearate as a roughening agent and one of the following: a petroleum oil with an amine and candelilla wax as a hydrophobic material. 15. A fertilizer according to any preceding claim, wherein the outermost surface of the granule has a micro-rough surface caused by a moisture control coating. 16. A method for producing coated fertilizer granules for regulating moisture absorption, wherein the method comprises: use of fertilizer granules; and applying a coating to the fertilizer granules from a material for regulating moisture absorption, containing a hydrophobic material and a roughening component, wherein the roughening component contains particles that provide a micro-roughness of the surface on the outermost surface of the coated granules. 17. The method according to claim 16, wherein the coating on the fertilizer granules comprises: coating the fertilizer granules with a roughening agent; and subsequent coating of the fertilizer granules with a roughening component with a hydrophobic material applied to it. 18. The method according to claim 16, wherein the coating on the fertilizer granules comprises: combining a roughening component and a hydrophobic material; and subsequent application of a coating of a combined roughening component and hydrophobic material to the fertilizer granule. 19. The method according to any one of claims 16-18, wherein the roughening component comprises solid particles with a particle size in the range from 10 μm to 150 μm. 20. The method according to any one of claims 16-19, wherein the roughening component is selected from the group consisting of the following: silicates, sand, phosphorite, calcium carbonate, gypsum, zinc, manganese, iron, copper, molybdenum, boron, chloride, cobalt, sodium, sulfur in the form of sulfate, elemental sulfur, zinc stearate, sodium stearate, stearic acid, powdered potassium carbonate and combinations thereof. 21. The method according to any one of claims 16-20, wherein the roughening component is contained in an amount equal to from 0.01 wt.% to 10 wt.% based on the total mass of the granule. 22. The method according to claim 21, wherein the roughening component is contained in an amount equal to from 0.1 wt.% to 1.0 wt.% based on the total mass of the granule. 23. The method according to any one of claims 16-22, wherein the hydrophobic material component comprises a wax, an oil, a metal salt of a fatty acid, or a combination thereof. 24. The method of claim 23, wherein the hydrophobic material component comprises a wax selected from the group consisting of candelilla wax, beeswax, carnauba wax, vegetable wax, paraffin, raw paraffin, microcrystalline wax, an emulsion of wax and oil, and combinations thereof. 25. The method of claim 23, wherein the hydrophobic material component comprises an oil selected from the group consisting of white liquid paraffin, petroleum oil, canola oil, sunflower oil, soybean oil, castor oil, linseed oil, olive oil, modified vegetable oils, and combinations thereof. 26. The method according to any one of paragraphs. 16-25, wherein the hydrophobic material is contained in an amount equal to from 0.01 to 10% based on the total mass of the fertilizer granule. 27. The method according to claim 26, wherein the hydrophobic material is contained in an amount equal to 0.5 to 2.0 wt.% based on the total mass of the fertilizer granule. 28. The method according to any one of claims 16-27, wherein the base of the fertilizer granule is selected from the group consisting of the following: nitrates, urea, potassium chloride, potassium sulfate, monoammonium phosphate (MAP), diammonium phosphate (DAP), simple superphosphate, triple superphosphate, potassium phosphates, calcium phosphates and combinations thereof. 29. The method of claim 16, wherein the moisture control coating comprises a wax emulsion containing ZnO. 30. The method of claim 16, wherein the moisture control coating comprises zinc stearate and/or sodium stearate as a roughening component and one of the following: a petroleum oil with an amine and candelilla wax as a hydrophobic material.

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