CS224333B1 - Agent for finishing surface of granulated or crystalline fertilizers and salts - Google Patents

Description

The present invention relates to a composition for the surface treatment of granulated crystalline industrial fertilizers and salts.

Industrial fertilizers containing water-soluble components such as nitrates, sulphates, chlorides, phosphates and the like, either alone or in combination, are characterized by a greater or lesser sintering tendency, depending on the production technology. This property is unfavorable especially during long-term storage and consequently affects the physico-mechanical and application properties, especially the spreading quality.

In a number of cases, fertilizers with a higher tendency to sinter cannot be used at all without prior treatment / crushing or sorting.

However, any additional handling entails an increase in costs and is also associated with the risk of a change in granulometry (an increase in dust fractions by secondary dust generated by the crushing). Therefore, the effort of manufacturers is to either completely stop or reduce the sintering of fertilizers.

Improvement of the properties of industrial fertilizers and salts can be achieved both by technological interventions directly in the production process (evaporation, drying, granulation, sorting, etc.) as well as the final treatment of the finished product. A number of methods for reducing caking and the substances used for this purpose have been described. In addition to inorganic powders with a purely separating effect, such as kaolin, diatomaceous earth, talc, cement drift, metallurgical drift etc., the particles are also coated with hydrophobic substances (oils, waxes, organic polymers) for the same purpose. At other times, substances are used in which the anti-caking effect is based on the formation of an ionic bond between the composition and the salt. This group includes arylalkylsulfonates and fatty amines. A common feature of both groups remains the low concentration in which they are applied to the fertilizer; it is in the order of hundredths to tenths of a percent.

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The physical properties of the above formulations in many cases (fatty amines) require hot application. Due to the small amount of deposited substance, homogeneous coverage of the entire volume of the finalized material is not always achieved, which reduces the degree of utilization of often expensive preparations.

Of the neutral substances, mineral oils are most often used for surface treatment. In general, these oils are prepared by distilling off the oil, yielding several oil fractions having different boiling points and viscosities. The oil fractions are mixtures of paraffinic, naphthenic and aromatic hydrocarbons. In addition, heterogeneous compounds ₁ containing sulfur, nitrogen and oxygen are also present. Of the aromatic hydrocarbons, there are on the one hand single-ring alkylated hydrocarbons, the so-called monoaromatics, but in particular multi-ring di-, tri- and polyaromatic hydrocarbons.

In most cases, the primary oil fractions * need to be refined for industrial purposes, ie to reduce the content of aromatic hydrocarbons, especially polyaromates, as well as sulfur, nitrogen and oxygen compounds. By refining, the hydrocarbon composition and physicochemical properties, such as aromatic carbon content, viscosity index, polar or polarizable substances, surface tension, air stability, etc. are changed.

Because most of the mineral oils are made from paraffinic petroleum, the primary oil fractions also contain hard paraffin and are not liquid at normal temperature. Paraffins are removed from these fractions by a relatively expensive process - solvent dewaxing.

Changes in the composition and properties of oils that occur during refining of mineral oils depend not only on the degree of refining, but also on the type of refining process used. The most widespread technology is selective refining, in which

- 3 224 333 remove unwanted components with selective solvents. A new process is hydrogenation refining in which less suitable oil components are converted to the desired components by the action of hydrogen. Heterogeneous compounds are converted to hydrocarbons to form hydrogen sulfide, ammonia and water. In hydrotreating, especially high pressure, significant changes occur and oils refined in this way differ substantially in their composition and properties from mineral oils refined with selective solvents.

It has now been found that when using fatty amines as anti-caking agents, higher effects can be obtained when mixed with a hydrocarbon component when a high pressure hydrogenated petroleum fraction having a distillation range of 300 to 460 ° C with a viscosity of 2 to 5 is used as the hydrocarbon component.

Λ mm 7 / s at 100 ° G, with a viscosity index of 70 to 110, preferably 70 to 90 units, which results from high pressure hydrotreating of the primary oil fraction.

The high-pressure refined petroleum fraction contains only a small amount of sulfur, nitrogen and oxygen compounds (in thousandths of a percent) and has a substantially reduced aromatic hydrocarbon content and a different hydrocarbon composition compared to the primary fractions and to the conventional refined mineral oils. In addition, the fraction contains 4 to 8% hard paraffin, but has a pour point of about + 5 ° C and is easy to handle at normal temperatures.

The above composition and properties of the petroleum fraction are beneficial when used as one component of an anti-caking agent, which specifically enhances the anti-caking effect of the other component, the fatty amine, which makes it possible to reduce its concentration when applied to the fertilizer while achieving a higher anti-caking effect. The use of this high-pressure hydrogenated petroleum fraction is also supported by the fact that it is one of the substances with little or no biological irritation,

-4 non-inflammatory.

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The advantage of the anti-caking agent according to the invention is therefore primarily its low viscosity, which ensures easy spraying by means of a pressure or air nozzle, as well as a lower freezing point compared to pure amines (approx. The expensive component of the mixture - the aliphatic amine - is applied to the surface of the particles in finely divided form and the anti-caking effect is enhanced by the simultaneous action of the amine, the hydrotreated petroleum fraction and paraffin, which form a coherent hydrophobic coating.

The advantages resulting from the use of the composition according to the invention stand out best from a comparison of the anti-caking effects measured in the laboratory tests by the caking test:

sintering index /% / ammonium nitrate with a limestone content of 27.5% N, untreated

00 ammonium nitrate with limestone containing 27.5% N, treated with 0.05% octadecylamine ammonium nitrate with limestone containing 27.5% N, treated with simultaneous application of 0.03% octadecylamine and 0.0? % selectively refined min. ammonium nitrate limestone oils with limestone containing 27.5% N, treated by simultaneous deposition of 0.03% octadecylamine and 0.07% hydrotreated petroleum fraction of the invention. in \ 333

It should be pointed out that the cost of treating 1 ammonium dime with limestone with 27.5% N alone by octadecylamine alone is nearly half the cost of applying the composition of the invention.

Examples

Example 1

A mixture of octadecylamine and a hydrotreated petroleum fraction at a concentration of 30% octadecylamine-70% fraction at a concentration of 0.1% was applied to the ammonium nitrate with limestone / cooled to 28 ° C in a powdering drum at 40 ° C. fertilizer weight. The sintered content of the treated material showed a value of 65 N. The bulkiness reached 98% after 14 days of storage in a layer of 7 bags,

Example 2

The combined multi-component fertilizer NPK-1 at 20 ° C was treated by applying 0.1% octadecylamine to a hydrotreated petroleum fraction (30:70 ratio) heated to 40 ° C. After adjustment, the sintering of the fertilizer fell to an average of 20% of the baseline value and the flowability after 14 days of storage in the 7 sack figure was ΙΟΟ ^ πί.

Example 3

The combined multi-component fertilizer NPK-1 at 20 ° C / was treated by adding 0.05% octadecylamine / hydrotreated petroleum fraction (30% octadecylamine, 70% fraction) heated to 40 ° C. After three months of storage in a layer of 7 bags, the flowability of the fertilizer was 100%.

Example. 4

Combined multi - component fertilizer NPK - 1 warm 25 ⁰ C ₍ se

6,224,333 was surface treated by applying 0.1% of a mixture containing octadecyl min and a hydrotreated 20: 80 petroleum fraction heated to 40 ° C. After adjustment, the caking rate dropped to 25% of baseline.

Example 5

The combined multi-component fertilizer NPK-1, 20 ° C warm, adjusted by applying 0.1% of a blend consisting of 30% octadecylamine and 70% hydrotreated petroleum fraction heated to 40 ° C was subsequently coated with 0.2% rubber kaolin. After two months of storage in bulk in a 3 m layer, the fertilizer was free-flowing, with no tendency to sinter.

Claims (2)

A composition for the treatment of granular and / or crystalline industrial fertilizers and salts, applied at a concentration of 0.05 to 0.5%, and preferably 0.1%, by weight of the fertilizer, consisting of a mixture of straight chain aliphatic primary amines having a carbon number of 12 to 18, preferably 16 to 18, with a non-polar component, characterized in that it contains up to 60%, preferably 20-30% of a primary aliphatic amine and 40-95%, preferably 70-80% of a hydrotreated petroleum fraction with a distillation range of 300 to 460 ° C, With a viscosity of 2 to 5 mm / s at 100 ° C and a viscosity index of 70 to 110, preferably 75 to 95 units, with a maximum of 10% aromatically bonded carbon and 4 to 8% hard paraffin.