WO2018232479A1

WO2018232479A1 - Highly concentrated liquid composition comprising elemental sulphur and process for coating fertilizers using said highly concentrated liquid composition

Info

Publication number: WO2018232479A1
Application number: PCT/BR2018/050104
Authority: WO
Inventors: Ubirajara PERON; Glauco Mariano TEIXEIRA; Juliana Da Silva GOMES; Camille Nunes LEITE
Original assignee: Adfert Aditivos Indústria E Comércio Ltda.
Priority date: 2017-06-22
Filing date: 2018-04-16
Publication date: 2018-12-27
Also published as: BR102017013603A2; MA47665B1; MA47665A1

Abstract

The present invention relates to a manner of coating fertilizer granules with a sulphur solution which is highly concentrated in the element of interest. Furthermore, the present application describes a novel method of application for adding the sulphur solution in varying doses to load the content required by the client, and also relates to the use of said sulphur-containing fertilizers for cultivating agricultural products in sulphur-deficient soils. In addition, the present invention relates to agricultural products for use on soils, particularly on sulphur-deficient soils which need to be treated with sulphur-containing fertilizers of the present invention. The present invention allows the combined use of elemental sulphur, or sulphur from other sources, in combination with other elements, which can be macronutrients or micronutrients.

Description

HIGHLY CONCENTRATED LIQUID COMPOSITION

COMPREHENSING ELEMENTAL SULFUR, AND PROCESS OF COLLECTION OF FERTILIZERS THROUGH HIGHLY CONCENTRATED LIQUID COMPOSITION

FIELD OF THE INVENTION

The present invention relates to the method of coating the fertilizer grains with a highly concentrated sulfur solution in the element of interest. Thus, an innovative application methodology for aggregating the sulfur solution in varying dosages to load the required content to the customer is described.

BACKGROUND OF THE INVENTION

[002] In addition to primary macronutrients

(such as carbon, hydrogen, oxygen, nitrogen, phosphorus and potassium), micronutrients and secondary macronutrients are essential elements for plant growth, but are required in much smaller quantities when compared to the required amounts of the primary macronutrients.

Secondary macronutrients may include, for example, calcium (Ca), sulfur (S) and magnesium (Mg). Micronutrients may include, for example, boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), zinc (Zn), chlorine (Cl), cobalt ) and combinations between them.

In incorporating secondary macronutrients during the manufacture and / or incorporation of one or more micronutrients directly into the fertilizer granules, such as NPK or phosphate fertilizers, when they are being produced, it occurs that in each fertilizer granule phosphate ends up having a concentration of the secondary macronutrient and / or desired micronutrient (s) with a uniform distribution in the granular fertilizer.

However, when the selected secondary macronutrient and / or micronutrient (s) contacted with components of the fertilizer being mixed under high temperature conditions during manufacturing, the rate of chemical reaction with the phosphates is increased, which may reduce plant availability of some micronutrients because the micronutrients remain in the phosphate granules.

[006] There are numerous works dedicated to the manufacture of sulfur-containing fertilizers in their composition. The growing world demand for sulfur-containing fertilizers stems from the low-yield crops ratio, in some cases, which may be related to soil sulfur deficiency.

[007] Manufacturing processes for sulfur-containing fertilizers of the phosphate type often involve the use or incorporation of sulfates.

[008] US4377406 or US4762546 have the disadvantage that the sulfates are very mobile in the soil and therefore leachable. The elemental sulfur, however, is not leached, as are sulfates. It is, therefore, more advantageous to have the sulfur present in the elemental form.

[009] In addition, elemental sulfur offers some additional benefits in fertilizers:

- acts as a fungicide against certain microorganisms,

- acts as a pesticide against certain pests the soil and the plants,

- assists in the decomposition of plant residues,

- improves the use of phosphorus and nitrogen,

- reduces the pH of alkaline and limestone soils.

Thus, sulfur incorporation in the form of elemental sulfur is advantageous to fertilizers containing or not sulfur.

Processes for the manufacture of sulfur-containing fertilizers, where elemental sulfur is used, are known in the art. Most methods involve incorporating molten sulfur into the fertilizer.

US5653782 discloses a process for the manufacture of sulfur-containing fertilizers wherein a substrate containing fertilizer particles is heated to a temperature above the melting point of the sulfur and then mixed with sulfur.

According to said document, the sulfur is melted by the heat provided by the preheated particles of the fertilizer, producing a poorly homogeneous coating on the fertilizer particles.

The homogeneous coating is visually observed in the granules of fertilizers found in the field, due to temperature gradients observed during the coating process, poor anchoring of the sulfur on the surface of the granules and low malleability of the sulfur, ie these facts provide heterogeneity in fertilizer granules and / or losses by handling and transport.

[0015] US3333939 describes the coating of ammonium phosphate with molten sulfur. The granules are coated in a separate unit in which the sulfur is fed by contacting the granules with the molten sulfur or with an ammonium polysulfide solution. Thereafter, the coated granules are dried.

Alternatively, US 3333939 teaches a process for the preparation of sulfur-containing fertilizer particles in which the sulfur is dispersed throughout the particles. In this process, the ammonia and the phosphoric acid are allowed to react to form the ammonium phosphate. The ammonium phosphate formed is fed to a granulator in which it is mixed with urea and dry sulfur. The granules thus obtained are dried in a drier.

The drawback of the first process of US3333339 is that the sulfur coating must use molten material, which makes the process very dangerous due to the risk of accidents.

The second process, however, has the disadvantage of requiring the handling of solid sulfur, and the handling and grinding of solid sulfur are highly dangerous due to the formation of dust and the risk of explosions.

[0019] US5571303 relates to a process for the manufacture of fertilizers in which they are first reacted with ammonia, water and phosphoric acid to form ammonium phosphate. Thereafter, the ammonium / water phosphate mixture is mixed with molten sulfur. The mixture thus obtained and is maintained at temperatures of 120-150 ² C until granulation. One disadvantage of this process is that, because of the previous formation of the ammonium phosphate, a lot of water is required to keep the salt dissolved, in addition to a solid ammonium phosphate being formed when relatively small amounts of water are used. Another point is the high temperature of the mixture during the process, which generates energy costs and the same risks shown previously.

Thus, the homogeneous distribution of sulfur throughout the granule may be obstructed by the existence of such solid ammonium phosphate.

Since problems with the manufacture of sulfur containing fertilizers of the ammonium phosphate type continue to exist, there is a need for a manufacturing process for such fertilizers which will lessen or even avoid the problems experienced hereinbefore.

Further, it is possible to mix granules of the micronutrients or secondary macronutrients with the fertilizer grains to be a widely used practice. However, with this type of procedure, the segregation of the grains having different density and characteristics occurs, leaving the distribution of the granulated fertilizer mixture containing one or more elements of the type, granulated sulfur, micronutrient granules or unilifed secondary macronutrients, that is, there will be application of different amounts of fertilizer containing one or more type elements, granulated sulfur, micronutrient granules or secondary macronutrients along the soil.

[0024] WO 2008/024007 discloses a sulfur fertilizer, either in the form of globular granules or in the form of pellets which constitute solid liquid sulfur mixtures, bentonite, additional components and microelements favorable fertilizers, i.e. characterized by their content of 60-95% sulfur, 4-20% bentonite and 1-8% lignosulfonate.

Lignosulfonate is incorporated into the sulfur fertilizer molecules in order to allow the formation of granules or pellets that facially disperse in contact with soil moisture into the sulfur molecules, which have a particle size much smaller than fertilizers of this type.

GB2292140 also discloses sulfur / bentonite fertilizer compositions in which 1-30% by weight of a binder material, such as a lignosulfonate, may be added for the purpose of forming granules suitable for application of the sulfur in the soil.

In the case of sulfur-containing mixtures with other fillers, obtaining granules, the problems of segregation and non-homogeneous application in the soil persist, in addition to the fact that the size of the sulfur particles are large (up to 250 microns), the which reduces the conversion rate of elemental sulfur to sulfate by soil microorganisms, which would make sulfur available to plants.

WO90 / 03350 discloses a sulfur-based chemical soil broker in the form of pellets for agricultural use, said product comprising airborne sulfur powder, at least 3% by weight of an inert product selected from the group consisting of clay , bentonite, kaolin and mixtures thereof, at least 5% of a wetting agent, said components being mixed with one another and subjected to wet extrusion and subsequent drying to obtain the pellets. Said wetting agent may be a lignin sulfonate. However, WO 90/03350 relates to the handling of sulfur powder which is extruded, which shows the same risks of accidents.

Regardless of the improvements disclosed in the prior art, there are still problems with the manufacture of fertilizers containing elemental sulfur.

In particular, the hazards of elemental sulfur dust, sulfur melt and friction remain a major concern as they may cause a fire / explosion.

Therefore, there remains a technical need for granular fertilizers containing one or more elements of the type, granular elemental sulfur, micronutrient granules or secondary macronutrients in their composition and the manufacturing processes of such fertilizers that decrease or even prevent the problems of experienced in the art.

Another point to be observed in the commercially sold products are the concentrations of the type elements, granular elemental sulfur, micronutrient granules or secondary macronutrients, which have very low concentrations and / or allow no variations, a fact which is possible with the present invention.

BRIEF DESCRIPTION OF THE INVENTION

The aim of the present invention is to address the need for a product with a lower risk of sulfur handling problems in powder for incorporation into mineral, organic, inorganic and organomineral fertilizers.

Thus, the present invention describes a product (formula and process) and an application technology for producing fertilizers coated with elemental sulfur or in other forms containing or not in their composition macronutrients primary and / or secondary or micronutrients, essentially free non-greasy, free-flowing or non-blocking, friction-resistant or abrasion-resistant coatings which have no type of polymeric or non-polymeric top coat, thus having a gradual and proportional release depending on the soil conditions.

The present invention provides a product having a reduced particle size, less than 50 microns, which in turn has a favored conversion and, consequently, provides greater plant availability.

According to the present invention, there is provided a formula, process for manufacturing the highly concentrated solution and a system for applying this solution to the surface of the fertilizer granule which may or may not contain an initial amount of sulfur in its formulation, production and application.

The highly concentrated liquid composition containing elemental sulfur comprises:

- a highly concentrated suspension of elemental sulfur containing or not in the composition other secondary macronutrients or micronutrients

- at least one non-ionic surfactant (preferably in the liquid phase), - at least one dispersant,

- optional presence of biocides and pH regulators,

said formulation being able to overcome all the problems reported above.

Among the macronutrients and micronutrients that may be present in the formulation we have as macronutrients: phosphorus, potassium, calcium, sulfur, nitrogen and magnesium; and as micronutrients: iron, zinc, copper, manganese, selenium, chromium, iodine, fluorine, arsenic, boron, molybdenum, cobalt, tin, nickel, vanadium and silicon which may be associated depending on the need.

It is to be mentioned that said formulation may further comprise macronutrients, micronutrients, surfactants, biocides, pH adjusters, dispersants, defoamers, thickeners, among others.

Among the macronutrients, there may be at least one of: phosphorus, potassium, calcium, sulfur, nitrogen and magnesium, which may be associated depending on the need.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows view 1 of the application plant of the highly concentrated solution.

Fig. 2 shows view 2 of the application plant of the highly concentrated solution.

Fig. 3 shows a first detailed view of the highly concentrated solution delivery system. Fig. 4 shows a second detailed view of the highly concentrated solution delivery system.

Fig. 5 is a photograph of the highly concentrated solution application system at a first glance.

Fig. 6 is a photograph of the highly concentrated solution application system in a second view.

DETAILED DESCRIPTION OF THE INVENTION

Among the micronutrients, there may be at least one of iron, zinc, copper, manganese, selenium, chromium, iodine, fluorine, arsenic, boron, molybdenum, cobalt, tin, nickel, vanadium and silicon, which may be associated depending on the need.

Said surfactant is at least one of: 6 EO isodecyl alcohol, 6 EO isotridecyl alcohol, 8 EO isotridecyl alcohol, 9 EO isotridecyl alcohol, 10 EO isotridecyl alcohol, 12 EO isotridecyl alcohol, 6 EO lauryl alcohol, lauryl alcohol 7 EO, lauryl alcohol 9 EO 13.4, lauryl alcohol 10 EO, castor oil 30, castor oil 36 EO, castor oil 40 EO, hydrogenated castor oil 40 EO, ethoxylated nonylphenol 8 EO, nonylphenol ethoxylated 9.5 EO , ethoxylated nonylphenol 10 EO, among others.

Said pH adjuster is at least one of: sodium hydroxide, potassium hydroxide, ammonium hydroxide, monoethanolamine, diethanolamine, triethanolamine, among others.

Said biocide is at least one of: compounds and / or compositions of 5-chloro-2-methyl-4-isothiazolin- 3-one, 2-methyl-4-isothiazolin-3-one, 1,2-benzoisothiazolinone, isoinolinone, aldehydes, among others.

Said thickener is at least one of: carboxymethylcellulose, pectin, gellan gum, konjac gum, gum arabic, xanthan gum, clay, modified clay, sodium bentonite, calcium bentonite, guar gum, alginate, agar agar, among others. Preferably, said thickener is sodium bentonite, among others.

Said dispersant is at least one of: sodium sulfonate, sodium naphthalene sulfonate, sodium polynaphthalene sulfonate, sulfonated polymelamines, aromatic polymers, organic polymers, sodium lignosulfonate, condensate alkyl naphthalene sulfonate and sodium lignosulfonate, condensed sodium naphthalene sulfonate, acrylic polymer solution, among others.

Said antifoam is at least one of: emulsified copolymer organosiloxane, polydimethylsiloxane, silicone emulsion, among others.

Accordingly, the formulation claimed by the present invention is comprised of:

Component Percent (%)

Water 15.0 - 40.0

Sulfur 60.0 - 80.0

Biocides 0.1 - 0.5

Tensitives 0.1 - 2.0

Dispersants 0.1 - 2.0

Antifoam 0.1 - 0.5

Thickener 0.1 - 2.0

Regulators of pH 0,1 - 2,0% The formulation requires particle size control to have the maximum particle diameter in microns of approximately 5 microns and a maximum of approximately 250 microns.

Particularly, particles from about 5 microns to about 100 microns are preferred, particles of approximately 0.5 microns to about 20 microns are still more particularly preferred.

Accordingly, the formulation intended by the present invention has the following characteristics:

(a) pH in the range from 2 to 14, from about 2 to about 10, particularly from 2.0 to 8.0, and

(b) a minimum viscosity of about 500 and a maximum of about 100,000 cP (at a temperature of 25 ° C), particularly about 500 to about 10,000 cP, and more particularly about 200 to about 2000 cP.

Due to the characteristics of the formulation in question, especially with respect to sulfur concentrations, as well as physical characteristics such as viscosity, it is possible to obtain an improved product capable of acting on a wide range of mineral, organic, inorganic fertilizers and organomineral, but such application is not restricted to these fertilizers alone.

Exemplifying compounds include phosphates, such as:

- ammonium phosphate (including: monoammonium phosphate (MAP) and diammonium phosphate (DAP), and superphosphates simple and triple);

- nitrates (such as: ammonium nitrate and potassium nitrate);

- sulfates (such as: ammonium sulphate, magnesium sulphate and potassium sulphate);

chlorides (such as: potassium chloride, limestone, dolomite); and

- mixtures thereof.

For the manufacture of the sulfur-based formulation, the step of adding all the components of the formulation to produce a highly concentrated suspension of elemental sulfur, whether or not containing other macronutrients or micronutrients in the composition, is presented in a reduction system of the particle size, which is capable of guaranteeing a greater stability to the formulation and a greater efficiency of conversion and, consequently, absorption by the plants.

For the production process of said formulation, a high shear system should be used, in which it is possible to reduce the particle size on the nanoparticle scale, depending on the need. In this case, it would be necessary to adjust the process time to obtain the desired particle size.

In accordance with the present invention, a greater flexibility in the suitability of NPK formulations is sought for better concentrations of the elements alone or together, so as to better meet the needs of each soil and crop. The present invention further describes an innovative system for applying said formulation to the surface of the fertilizer granules.

Thus, a liquid solution application system consisting of a dynamic application has also been developed. In other words, the process of applying the highly concentrated liquid solution of elemental sulfur containing or not in the composition other macronutrients or micronutrients consists of the following steps:

a) directing the highly concentrated liquid sulfur solution in a high rotation misting system, which will produce finely divided droplets;

b) spraying said liquid solution on the fertilizer which is being rotated in an anti-spray direction;

c) impact of the droplet of said liquid solution against the grain of the fertilizer;

d) incrustation of the liquid material on the surface of the grain, i.e. incrustation in the grooves, roughness and porosity) thereby obtaining a greater anchorage (fixation) of the product;

drying takes place throughout the spraying process, said drying consisting of an air flow tangential to the rotation of the fertilizer,

and drying is performed very quickly to avoid solubilization of the grain, and

wherein the drying can be carried out by means of heat associated with or not at a reduction of the ambient pressure during the application. The process of applying the highly concentrated liquid solution of elemental sulfur containing or not in the composition other macronutrients or micronutrients maintains its final efficiency and quality due to the fact that it is atomized and applied tangentially at high speed, which causes a penetration in porosity and natural roughness of substrates having similarity to electrostatic painting processes.

Claims

A HIGHLY CONCENTRATED LIQUID COMPOSITION COMPREHENSING ELEMENT SULFUR, characterized in that it comprises a highly concentrated suspension of elemental sulfur, at least one nonionic surfactant, at least one dispersant, water, among others.

The composition according to claim 1, characterized in that it may optionally include primary and / or secondary macronutrients, micronutrients, surfactants, biocides, pH adjusters, dispersants, defoamers, thickeners, among others.

A composition according to one of claims 1 or 2, characterized in that the macronutrients can include one or more of: phosphorus, potassium, calcium, sulfur, nitrogen and magnesium; and the micronutrients may include one or more of iron, zinc, copper, manganese, selenium, chromium, iodine, fluorine, arsenic, boron, molybdenum, cobalt, tin, nickel, vanadium and silicon.

A composition according to any one of claims 1 to 3, characterized in that the surfactant is at least one of: 6 EO isodecyl alcohol, 6 EO isotridecyl alcohol, 8 EO isotridecyl alcohol, 9 EO isotridecyl alcohol, 10 EO isotridecyl alcohol, alcohol isotridecyl 12 EO, lauryl alcohol 6 EO, lauryl alcohol 7 EO, lauryl alcohol 9 EO 13.4, lauryl alcohol 10 EO, castor oil 30, castor oil 36 EO, castor oil 40 EO, hydrogenated castor oil 40 EO , ethoxylated nonylphenol 8 EO, nonylphenol ethoxylated 9.5 EO, nonylphenol ethoxylated 10 EO, among others.

The composition according to any one of the preceding claims, Claims 1 to 4, characterized in that the pH adjuster is at least one of: sodium hydroxide, potassium hydroxide, ammonium hydroxide, monoethanolamine, diethanolamine, triethanolamine, among others.

Compound according to any one of claims 1 to 5, characterized in that the biocidal product is at least one of: 5-chloro-2-methyl-4-isothiazolin-3-one compounds, and / or compositions, 2-methyl- 4-isothiazolin-3-one, 1,2-benzoisothiazolinone, isoinolinone, aldehydes, among others.

Composition according to any one of Claims 1 to 6, characterized in that the thickener is at least one of: carboxymethylcellulose, pectin, gellan gum, konjac gum, gum arabic, xanthan gum, clay, modified clay, sodium bentonite, calcium bentonite , guar gum, alginate, agar agar, among others, which is preferably sodium bentonite.

Composition according to any one of claims 1 to 7, characterized in that the dispersant is at least one of: sodium sulfonate, sodium naphthalene sulfonate, sodium polynaphthalene sulfonate, sulphonated polymelamines, aromatic polymers, organic polymers, lignosulfonate of sodium, condensed alkyl naphthalene sulfonate and sodium lignosulfonate, condensed sodium naphthalene sulfonate, acrylic polymer solution, among others.

A composition according to any one of claims 1 to 8, characterized in that the antifoam is at least one of: emulsified copolymer organosiloxane, polydimethylsiloxane, silicone emulsion, among others.

A composition according to any one of the preceding claims, Claims 1 to 9, characterized in that it is essentially powder-free and non-greasy because it is free-flowing or non-blocking because it is resistant to friction or abrasion because it is polymeric or non-polymeric overcoating because it is gradually released and proportional, depending on soil conditions.

A composition according to any one of claims 1 to 10, characterized in that it is applied to the surface of mineral, organic, inorganic and organomineral fertilizers, among others.

A composition according to any one of claims 1 to 11, characterized by having a maximum particle size diameter of 5 microns to 250 microns, preferably 5 microns to 100 microns, and more preferably 0.5 microns to 20 microns microns.

A composition according to any one of claims 1 to 12, characterized in that the components vary according to the following ranges:

water: 15-40%;

sulfur: 60-80%;

biocide: 0.1-0.5%;

surfactant: 0.1-2%;

dispersant: 0.1-2%;

antifoam: 0.1-0.5%;

thickener: 0.1-0.5%;

- pH adjuster: 0.1-2%.

A process for the recovery of fertilizers by means of the highly concentrated liquid composition as defined in any one of claims 1 to 13, characterized in that it comprises the following steps: a) directing the highly concentrated liquid sulfur solution in a high rotation misting system, which will produce droplets;

b) spraying said liquid solution on the fertilizer which is being rotated in the anti-spray direction;

d) fouling of the liquid material on the surface of the grain;

and drying is performed very quickly to avoid solubilization of the grain, and

wherein the drying can be carried out by means of heat associated with or not at a reduction of the ambient pressure during the application.