RS51732B - Nitrogen-sulfur fertilizer containing limestone and process for its extraction - Google Patents

Abstract

Fertilizer containing one mass fraction of ammonium sulphate, one mass fraction of ammonium nitrate and one mass fraction comprising limestone and / or carbonate and / or hydrogen carbonate of magnesium and / or calcium, characterized in that the mass fraction comprising limestone and / or carbonate and / or hydrogen carbonate of magnesium and / or calcium is at least 5 to 25 weight percent of fertilizer, and the weight fraction of ammonium sulfate is at least 5 weight percent of fertilizer. The application contains 14 more claims.

Description

The invention relates to the field of fertilizers.

In addition to water, carbon dioxide and sunlight, the main nutrients nitrogen, potassium carbonate and phosphate, as well as secondary nutrients and trace elements are necessary for plant growth. And sulfur is a secondary nutrient of vital importance, primarily for the synthesis of proteins in plants, which take it, primarily in the form of sulfate, both through the roots and through the leaves.

In the last one to two decades, a decrease in the sulfur content in the soil used for agriculture can be noted. It is caused by reduced sulfur emissions due to increased desulfurization of flue gases and reduction of sulfur content in fuel. Due to measures to preserve clean air, the intake of sulfur from the atmosphere decreased from up to 100 kg/ha in the 80s to an average of around 6 kg/ha. The use of sulfur by plants must be compensated by targeted fertilization measures.

The demand for sulfur-containing fertilizers, especially nitrogen-containing simple fertilizers with sulfur, is increasing. Sulfur and nitrogen work together in the plant. This can be clearly seen from the content of nitrogen and sulfur in the plant mass. At optimal supply, the ratio of nitrogen and sulfur in plants is at least 10:1. If that ratio changes to the detriment of the sulfur content, one should expect a lower yield and quality due to a lack of sulfur. Depending on the crop, 10 kg of nitrogen and, as a rule, 1 to 4 kg of sulfur are taken from the field with the fruits of the harvest.

US 3282674 describes a fertilizer containing ammonium sulfate, ammonium nitrate, 0.1 to 0.2 weight percent magnesium nitrate, magnesium sulfate, calcium nitrate and 0.1 to 2.0 weight percent calcium carbonate, magnesium carbonate, dolomite, ammonia, etc. The mass fraction of ammonium sulfate is, for example, 52 mass percent, and ammonium nitrate is 43 mass percent. That fertilizer can contain both ammonium nitrate and ammonium sulfate as a double salt 2NH4N03x (NH4)2S04.

One possibility to produce a simple nitrogen fertilizer containing sulfur is the production of ammonium sulfate nitrate, a mixture of double salts with the composition 1-3 NH4NO3<*>(NH4)3S04 and the rest of ammonium sulfate. Such ammonium-sulfate-nitrate is a salt of one weak acid and two strong acids and therefore has a slightly acidic reaction in aqueous solution. In the following text, the prefix "ammonium" means ammonium ion. Therefore, it essentially consists of ammonium nitrate and ammonium sulfate salts in different crystalline forms.

There are different processes for the production of ammonium sulfate nitrate. A review is given in Kirk Othmer, "Encyclopedia of Chemical Technology", 3rd Edition, Book 10, 1980, page 49.

Processes for the production of ammonium sulfate-nitrate can in principle be divided into three groups.

The first group contains procedures based on the neutralization of sulfuric acid and nitric acid with ammonia and granulation of the resulting ammonium-sulfate-nitrate solution. These processes are described in patents GB 798 690 (1958), GB 1 049 782 (1963) and US 2762699 (1957).

The second group contains processes for the production of ammonium sulfate-nitrate based on solutions of ammonium sulfate salts and ammonium nitrate salts. Most often, solid ammonium sulfate is added to a solution of ammonium nitrate and processed into granulated fertilizer. Processes are disclosed, for example, in EP 1 595 80 (2005) and GB 1 005 166 (1965; BASF).

The third group is based on the production of a supersaturated mixture of ammonium-nitrate and ammonium-sulfate and granulating the same during dry rotation of the product, usually in a drum granulator or screw granulator. Such processes are described, for example, in patents GB 1259 778 (1972, FisondsLtd.) and US 3 635 691 (1972).

Ammonium-sulfate-nitrate is less hygroscopic than ammonium-nitrate, however, due to additional reactions during storage, it is prone to sticking. The addition of additives, such as iron or aluminum salts, to improve product characteristics is described in the literature, for example in DE 972197 or GB 1 259 778.

An important disadvantage of ammonium-sulfate-nitrate when used in the field is its acidic properties in aqueous solution, which with long-term use lead to soil damage due to leaching of minerals and changes in soil biology. If ammonium-sulfate-nitrate is used for a long period without sufficient calcification of the soil, its acidity increases. This deteriorates the chemical properties of the soil. Due to the constant decrease in the pH-value of the soil due to the process of transforming ammonia nitrogen through the form of nitrite into the form of nitrate, soil calcification is becoming more and more important.

Therefore, it is desirable to find a simple procedure by which acidic ammonium sulfate-nitrate can be combined with limestone. Due to the alkaline reaction in the solution, limestone compensates for the drop in pH value. Such a procedure should provide a nitrogen-sulfur fertilizer that contains limestone and is suitable for use in the fields.

That problem is solved with an ammonium-sulphate-nitrate fertilizer that contains limestone, as well as a process for producing the same according to independent requirements.

The subject of the invention is a process for the production of nitrogen-sulfur fertilizer containing limestone and/or calcium and/or magnesium carbonate or hydrogen carbonate, indicated by the fact that a solution or solution of ammonium sulfate-nitrate is produced, which is mixed with limestone or appropriate calcium or magnesium salts in a mixing device, and fertilizer is obtained by granulating the solution.

The procedure is indicated by the fact that the solution or solution of ammonium sulfate-nitrate can be produced using one of the above-described methods for the production of ammonium sulfate-nitrate, and then by adding limestone or dolomite (dolomitic limestone) it is further processed into a nitrogen-sulfur fertilizer according to the invention.

Fertilizer, which can be produced by this process, is also an object of this invention.

The addition of limestone, i.e. dolomite, can be done in common mixing devices, such as in a mixing boiler.

It is preferable to add limestone or dolomite in two steps, where one part of the limestone is added to the mixing apparatus, while the other part of the limestone is added later to the granulating apparatus.

However, all limestone can be added directly to the granulation machine. This is especially useful when dealing with a screw granulator.

The product obtained according to the invention can be granulated in conventional granulating machines, such as drum granulators or screw granulators, and can easily be added to an ammonium sulfate nitrate production plant or to a plant for the production of other fertilizers, such as a nitro-phosphate plant.

A solution or solution of ammonium sulfate nitrate can be produced by any method. It is important, however, that it is obtained at a temperature at which the mixture can still be shaped and at which granulation can be carried out. As a rule, these are temperatures between 140° C and 160° C. The ratio of ammonium-nitrate and ammonium-sulfate in the ammonium-sulfate-nitrate solution should be 40:60 to 60:40 in order to enable the formation of the desired double salts.

If it is not possible to produce a melt or solution of ammonium sulfate nitrate with the above-mentioned properties, a portion of ammonium nitrate or ammonium sulfate can be added later, for example, simultaneously with limestone in the mixing apparatus or directly in the granulator, in order to achieve the desired content of nutrients in the product. This can be an advantage, because double salts 2NH4N03* (NH4) 2S04 can be formed faster when the content of ammonium nitrate in the solution is lower.

It is useful that the solution, that is, the solution of ammonium sulfate-nitrate, contains between 4 and 10 mass percent of water, on the one hand, so that it can still be well mixed with limestone, and on the other hand, so that the obtained suspension, which contains limestone, can be granulated in the usual devices without a large expenditure of energy.

It is also convenient to melt, or ammonium sulfate nitrate solution is obtained at high temperatures, especially at temperatures between 140 and 160° C, so that the suspension containing limestone does not cool down when adding limestone or dolomite. Temperatures above 18 0° should be avoided because thermal decomposition of ammonium nitrate is already possible at these temperatures.

Furthermore, it is useful that the solution or solution of ammonium sulfate nitrate already contains possibly necessary additives, such as iron or aluminum, which enable good storage of the finished fertilizer.

It is especially desirable that the ammonium sulfate-nitrate solution is a double salt solution obtained by neutralizing sulfuric acid with ammonia in the presence of ammonium nitrate. It is useful that the formed ammonium salts are double salts 2 NH4NO3* (NH4) 2SO4. If the reaction of the formation of double salts takes place only in the warehouse, solidification of the nitrogen-sulfur fertilizer can occur in the warehouse.

It is preferable that the reaction is carried out in the pH-range from pH=ldo pH=7, especially in the pH-range from pH=2 to pH=6.

Given that the pH-value of the solution, or ammonium-sulfate-nitrate solution is usually low, it is necessary to neutralize that solution, or solution before adding limestone. Neutralization can be done, for example, by adding ammonia.

Melting, or the ammonium-sulfate-nitrate solution can, however, be neutralized with a part of limestone. In this way, gypsum is created in the suspension, which contains calcium, while carbon dioxide is removed.

In processes for the production of ammonium sulfate-nitrate solutions, in which starting from solid ammonium sulfate and ammonium nitrate, there is a possibility to add limestone or dolomite to the ammonium nitrate solution together with solid ammonium sulfate. In that case, it is preferable to shape the fertilizer by compression between the rotating rollers.

Any source of limestone can be used as limestone, however, it is especially desirable to use limestone produced in the nitro-phosphate process. In a particularly desirable form of execution, that process is integrated into a device for the continuous production of complex fertilizer by the nitro-phosphate process. A unit for the production of ammonium nitrate of lime is usually connected to the nitro-phosphate unit. This can be combined with a device for the production of nitrogen-sulfur fertilizer containing limestone. Lime ammonium nitrate products and nitrogen-sulfur fertilizer containing limestone are often alternately produced in the same plant. In this way, nitrogen-sulfur fertilizer containing limestone can be produced as a by-product of complex fertilizer with a simple procedure.

A lime ammonium nitrate plant usually has a granulation unit that can be used to granulate a nitrogen-sulfur fertilizer containing limestone.

Dolomitic limestone can be used instead of pure calcium carbonate. In addition to calcium carbonate, it also contains magnesium carbonate. In the following text, the terms "limestone", "calcium carbonate" and "dolomite", i.e. "dolomitic limestone" can be interchanged, unless it is explicitly about the properties of dolomitic limestone in terms of magnesium content. The method allows the production of fertilizers containing one mass fraction of ammonium sulfate, one mass fraction of ammonium nitrate and one mass fraction consisting of limestone and/or one carbonate and/or hydrogen carbonate of magnesium and/or calcium, whereby the mass fraction consisting of limestone and/or one carbonate and/or hydrogen carbonate of magnesium and/or calcium amounts to at least 5 to 25 percent by mass, especially 8 to 20 mass percent, mass fraction of ammonium sulfate at least 5 mass percent, preferably 5 to 8 5 mass percent, especially preferably 30 to 50 mass percent of fertilizer.

The content of limestone, i.e. calcium carbonate or dolomitic limestone in the fertilizer according to the invention is given, unless otherwise stated, in mass percentages. In the finished fertilizer, the content of calcium (Ca<2+>) and magnesium (Mg<2+>) is determined analytically by complexometry and calculated as calcium carbonate and magnesium carbonate. If calcium carbonate contains additional minor components such as, for example, magnesium salts, the proportion of that component is calculated as if it consisted only of calcium carbonate, i.e. the mass fraction of the minority component is separated. For example, if 100 kg of the fertilizer according to the invention contains 10% of the mineral calcium carbonate, which in turn contains 10% of magnesium salt, the mass fraction of calcium carbonate in the fertilizer would be 9%. The nitrogen-sulfur fertilizer according to the invention contains at least 1.5 mass percent of limestone to increase the safety during transport and storage of the fertilizer. Preferably it contains 5-20% limestone, especially 10-16% limestone. In this way, the acidic properties of ammonium-sulfate-nitrate, which are evaluated negatively, are reduced, and at the same time, a high content of nitrogen and sulfur nutrients is achieved.

Dolomitic limestone can be used instead of pure calcium carbonate, so that the fertilizer contains magnesium in the form of magnesium carbonate. An amount of 2 to 4 weight percent magnesium is preferred. In the presence of calcium and magnesium, it has a favorable effect on the pH value of the soil as well as on the formation of humus. Magnesium can also be added in the form of magnesium oxide.

The nitrogen-sulfur fertilizer according to the invention furthermore contains at least 5 percent by mass of ammonium sulfate. It is preferable that it contains between 30 and 50% ammonium sulfate, which corresponds to a sulfur content in the final product between 7 and 12%. In this way, in addition to ammonium sulfate and limestone, enough ammonium nitrate is added to the fertilizer, and a large proportion of nitrogen in the fertilizer according to the invention is achieved. In addition, nitrogen is added through ammonium nitrate in the form of nitrate nitrogen, which quickly becomes accessible to plants. The mass proportion of ammonium nitrate in the fertilizer is 5 to 55 mass percent, preferably 35 to 45 mass percent.

The granulation of nitrogen-sulfur fertilizer, which contains limestone, according to the invention is carried out in granulation units customary for fertilizer production devices, for example in a drum granulator or in a screw granulator.

Particularly preferred, however, is granulation by spraying onto a granulation bed in a rotating drum. In doing so, it is desirable that the temperature of the raw material is between 100 and 150°C, and the temperature of the fertilizer suspension between 145 and 160°C. If the difference between the temperature of the raw material and the fertilizer suspension is too large, it can cause unwanted crystal formation due to rapid cooling of the solution.

Ammonium-sulfate-nitrate (ASN) produced in this way with up to 25% limestone (CaC03) causes less soil acidity than conventional fertilizers based on ammonium-sulfate-nitrate (ASN) and at the same time provides calcium. In places where there is a lack of sulphur, there is usually a lack of limestone as well. Application of acidic ammonium sulfate-nitrate without buffering with limestone can worsen calcium deficiency, because acidic fertilizers based on ASN with -187.5 kg CaO per 100 kg N have a strong effect on reducing the amount of limestone.

The basis for the financial evaluation of base-efficient ingredients in fertilizers is Sluijsmans' formula for the value of limestone (better base value) (1970). This formula reads: E (kg CaO/100 kg fertilizer) = 1.0 x CaO + 1.4 x MgO + 0.6 x K20 + 0.9 x Na20 - (o.4 x P205+ 0.7 x S03+ 0.8 Cl + 1.0 x N) . The following table gives the base values for several nitrogen-sulfur fertilizers:

When limestone is added to soils that have already been fertilized with ASN-based fertilizers, there is a danger that due to an uncontrolled increase in pH value, nitrogen is released, because calcium carbonate partially deprotonates ammonium salts into volatile ammonia due to its alkaline effect.

In contrast, the fertilizer according to the invention has the advantage that the proportions of ammonium salt and calcium carbonate are so harmonized as to minimize the evaporation of ammonia and thus the loss of nitrogen accessible to the plant. Therefore, calcium carbonate is very suitable as an addition to limestone and for ASN. In addition, the simultaneous application of lime fertilizer and nitrogen-sulfur fertilizer in one step increases the efficiency of the farmer's work.

The ratio of nitrogen to sulfur from 1:4 to 1:2, which is aimed for in the fertilizer according to the invention, optimally corresponds to the plant's needs for nutrients, because plants, as described at the beginning, due to the joint action of nitrogen and sulfur in the plant during the entire growth period, must have enough sulfur available in an acceptable form. The lack of sulfur, among other things, leads to insufficient use of nitrogen by the plant and, as a result, to poorer quality and lower yields.

Furthermore, according to Pronalsk, the fertilizer contains nitrogen both in the form of ammonia nitrogen and in the form of nitrate nitrogen.

Compared to fertilizing with so-called nitrogen-sulfur fertilizers based on ammonium nitrate and gypsum ("ammonium nitrate with sulfur" type of fertilizer, e.g. 24N+6S), the fertilizer according to Pronalsk has the advantage that it does not contain sulfur as difficult-to-dissolve gypsum, but as ammonium sulfate accessible to the plant. Gypsum (CaS04<*>2H20), which is poorly soluble in water

(2.02 g/l at 18° C according to Rompp's chemical lexicon)

it is considered a slow-acting sulfur fertilizer. A grain of fertilizer that contains "ammonium nitrate with sulfur" type gypsum, therefore, remains lying on the field for a long time so that sulfur is practically not accessible to plants. Ammonium sulfate, in contrast, is well soluble in water, so the plant can quickly take up the nutrient element sulfur in the form of sulfate anions.

However, the fertilizer according to the invention with the same nitrogen content (24 mass percent) and with a possible limestone content of 3 to 20 mass percent contains up to 6% more sulfur.

And from the point of view of safety, the fertilizer according to the invention has an advantage over other nitrogen-sulfur fertilizers such as ammonium-sulfate-nitrate. Ammonium nitrate is considered a dangerous substance in terms of transport, because it is prone to thermal self-decomposition. It is known that the addition of about 10% of calcium carbonate has a strong calming effect, which reduces the danger of explosion of, for example, calcium ammonium nitrate to about 12% of the same for ammonium nitrate. Given that the ammonium-sulfate-nitrate product has a low pH value, when the nitrate content in the fertilizer exceeds a certain value, it is also evaluated as critical. Therefore, adding 4 to 16 percent by mass of limestone significantly increases safety during production and transportation.

The method according to the invention differs from the method for the production of fertilizers of the "ammonium-nitrate with sulfur" type in a favorable sense, even from the point of view of process technology. If ammonium nitrate with sulfur (24N+6S) were to be produced in a production complex with a conventional nitro-phosphate device, it would be necessary to transform the existing calcium nitrate into calcium sulfate using sulfuric acid and to release the C02 produced during simultaneous production into the atmosphere. The C02 balance would be significantly burdened.

Calcium nitrate, which appears as a side product in the production complex during the production of NPK-fertilizers by the nitro-phosphate process, can be used in the process according to the invention, which is convenient. Calcium nitrate is used with C02

(a by-product of the NH3 device at the place of the device)

turns into calcium carbonate.

Production of nitrogen-sulfur fertilizer, which contains limestone, significantly improves the C02 balance in production. At the same time, the performance of that N+S fertilizer for agriculture is better than the performance of those currently on the market.

According to one form of execution, the fertilizer it contains is provided

- Total nitrogen 20 to 30%, preferably 22 to 26%, even more preferably 23 to 25%; - Ammonia nitrogen 10 to 25%, preferably 15 to 20%, even more preferably 16 to 18%; - Nitrate nitrogen 5 to 10%, preferably 6 to 8%; - Water-soluble sulfur compounds, preferably sulfates, with a mass fraction of 3 to 20%, preferably 7 to 16%, even more preferably 8 to 10%, which refers to the elemental sulfur content; - Calcium, calculated as calcium carbonate, 1.5 to 25%, preferably 8 to 20%, even more preferably 12 to 16%;

in relation to the total mass of fertilizer.

It may also contain other substances that improve storage capacity and increase the agrochemical effect of the final product.

Fertilizer is primarily used in the form of grains, i.e. granules, where the grains have an even round shape. The composition of the fertilizer is generally identical in each grain. This enables an even distribution of the fertilizer ingredients on the field, which would not be ensured if the ingredients were mixed in different grains.

It is desirable that the distribution of grain sizes is 2 to 3% >5mm; 8-12% 4-5mm; 15-19% 3.55-4 mm; 20 to 24% 3.15-3.55 mm; 25 to 28% 2-3.15 mm; 0.05 to 0.02% 1-2 mm; 0% < 1 mm, preferably 2.5% > 5 mm; 9.9% 4-5 mm; 17.3% 3.55-4 mm; 21.2% 3.15-3.55 mm; 26.1% 2-3.15 mm; 0.1% 1-2 mm; 0% < 1 mm.

Description of the pictures

Figure 1 describes the production of nitrogen-sulfur fertilizer,

which contains limestone, in a device for fertilizers with more nutrients with a capacity of about 500 tons per day, which is productively connected to one device for nitro-phosphate and one device for calcium, ammonium, and nitrate.

Figure 2 shows the production complex with one device for nitro-phosphate and one device for multi-nutrient fertilizer (NPK) as well as one device for calcium-ammonium-nitrate (KAN). The calcium-ammonium-nitrate solution created in the process with nitro-phosphate is converted into limestone and ammonium-nitrate solution in the calcium-nitrate transformation device (TKN). Both serve as raw materials for the production of calcium-ammonium-nitrate.

Figure 3 shows how the production of nitrogen-sulfur fertilizer containing limestone can be integrated into this complex without major reconstruction.

Fig. 1 shows individually the production of fertilizers according to the invention. The starting point is the introduction of nitric acid and crude phosphate into the Odda process. The horizontal flow diagram shows, starting from the Odda process, the production of classic NPK (nitrogen-phosphorus-potassium)-fertilizer by means of ammonification with ammonia and sulfuric acid and then the dosing of solid substances, during which the potassium component is introduced by adding potassium chloride.

Likewise, the calcium nitrate produced during the Odda process can now be taken to the calcium nitrate transformation device (vertical process). By adding carbon dioxide and ammonia and then concentrating ammonium nitrate by evaporation, calcium-ammonium-nitrate can be obtained

(CAN).

Also, by including another line to the calcium-carbonate and ammonium-nitrate mixture created in the TKN reactor by adding ammonia and sulfuric acid, a sulfur component can be added, which after optional addition of solids gives the fertilizer according to the invention (middle flow diagram in Figure 1).

This device configuration allows the use of a traditional device without adding a new reactor, as well as the use of existing granulation devices.

Figure 2 shows a typical configuration of equipment for the production of NPK and KAN fertilizers.

Figure 3 shows the configuration of such a device, shown in Figure 2, for the production of fertilizers according to the invention by adding another reactor, in which the ammonium nitrate produced in the KAN-line as well as the limestone produced in the Odda-process are inserted into an additional reactor in which the ammonium sulfate component is separately provided by neutralizing sulfuric acid with ammonia.

And this configuration uses the granulators located in the device, which is convenient.

Examples

Example 1:

Production of nitrogen-sulfur fertilizer suspension, which contains limestone, starting from ammonium nitrate and ammonium sulfate, as well as granulation of the suspension into nitrogen-sulphur fertilizer containing limestone on a laboratory scale.

Material: Ammonium nitrate, ammonium sulfate, limestone from the nitro-phosphate process, water.

Execution: Weight proportions of ammonium nitrate and ammonium sulfate are mixed in a ratio of 1:9 with a little water and dissolved in a sand bath. Then, 18 g of wet lime (from the nitro-phosphate device) was added to 100 g of the obtained ammonium-sulfate-nitrate solution; about 6% water, 0.5% P205) and the mixture is well mixed.

The resulting grain slurry of nitrogen-sulfur fertilizer, which contains limestone, was granulated in a laboratory machine and then classified.

The resulting granulate of nitrogen-sulfur fertilizer, which contains limestone, contained 23.6% nitrogen, of which 15.4% ammonium-nitrogen, 0.36% water and 8.9% sulfur. This corresponds to a limestone content of about 17%.

Example 2

The production of a suspension of nitrogen-sulfur fertilizer, which contains limestone, starting from a solution of ammonium nitrate, sulfuric acid, ammonia and dolomitic limestone, as well as the granulation of the suspension to fertilizer, a nitrogen-sulfur fertilizer, which contains limestone, on a large technical scale in a device for the production of fertilizers with more nutrients (see also Figure 1).

Raw materials: 65% ammonium nitrate solution, 96% sulfuric acid, ammonia gas, dolomitic limestone.

Execution: In the device for fertilizers with more nutrients, 7.85 m3/h of ammonium nitrate solution and 3.82 m3/h of water with 2.75 m3/h of sulfuric acid were mixed in the ammonization unit, and then it was neuralized in several steps at about 115°C. The resulting ammonium-sulfate-nitrate solution was then mixed with 2.42 t/h of dolomitic lime and additives such as ferrous sulfate. The slurry of nitrogen-sulfur fertilizer, which contains limestone, is shaped in a spherodizer into uniformly round granules. The resulting product, a nitrogen-sulfur fertilizer containing limestone, had the following composition: 25.7% nitrogen, of which 15.5% ammonium nitrogen, 7.7% sulfur, 0.19% water, 2.09% magnesium oxide.

Sifting analysis gave the following result: 2.5% > 5mm; 9.9% 4-5 mm; 17.3% 3.55-4 mm; 21.2% 3.15-3.55 mm; 26.1% 2-3.15 mm; 0.1% 1-2 mm; 0 % < 1 mm.

Example 3

Integrating the production of nitrogen-sulfur fertilizer containing limestone into a lime-ammonium-nitrate plant on the example of a production complex with a nitrophosphate plant (see figures 2 and 3).

The production of nitrogen-sulfur fertilizer, which contains limestone, can be integrated into this complex without major reconstruction. In order to produce such a fertilizer, a unit for the production of a melt or solution of ammonium sulfate-nitrate, for example, with a process starting from sulfuric acid and ammonia, is set up. Then, starting from the produced melt/solution of ammonium-sulfate-nitrate and from the limestone from the process with nitro-phosphate, the fertilizer according to the invention is produced. The same machines for granulation, drying, classification, etc. can be used for the production of lime ammonium nitrate, also for fertilizer according to the pronals; possibly only changes are needed.

Claims (15)

1. Fertilizer containing one mass share of ammonium sulfate, one mass share of ammonium nitrate and one mass share that includes limestone and/or carbonate and/or hydrogen carbonate of magnesium and/or calcium, indicated by the fact that the mass share that includes limestone and/or carbonate and/or hydrogen carbonate of magnesium and/or calcium is at least 5 to 25 percent by mass of the fertilizer, and the mass share of ammonium sulfate at least 5 percent by mass of fertilizer. 2. Fertilizer according to claim 1, indicated by the fact that the mass fraction of ammonium sulfate is 30 to 50 mass percent. 3. Fertilizer according to at least one of the previous requirements, indicated by the fact that it contains additional substances such as magnesium, calcium nitrate, zinc, iron, aluminum and/or phosphates in a total amount of less than 5 percent by mass. 4. Fertilizer according to at least one of the previous requirements, indicated by the fact that soluble magnesium salt is contained in the fertilizer. 5. Fertilizer according to claim 4, characterized in that the mass fraction of soluble magnesium salt, calculated as magnesium oxide, contains 1% to 4%. 6. Fertilizer according to at least one of the previous requirements, indicated by the fact that this fertilizer contains ammonium nitrate and ammonium sulfate as a double salt 2 NH4N03* (NH4) 2S04. 7. Fertilizer according to at least one of the previous requirements, indicated by the content of total nitrogen is 20 to 30 percent by mass of ammonia nitrogen from 10 to 25 percent by mass of nitrate nitrogen from 5 to 10 percent by mass of water-soluble sulfur from 3 to 20 percent by mass of limestone and/or carbonate and/or hydrogen carbonate magnesium and/or calcium from 1.5 to 25 mass percent in relation to the total mass of fertilizer. 8. The procedure for the production of fertilizers according to claims 1 to 7, indicated by the fact that the solution or solution of ammonium nitrate and ammonium sulfate is mixed with limestone and/or carbonate and/or hydrogen carbonate of magnesium and/or calcium in a mixer, and then by granulating the suspension, which contains limestone, fertilizer is obtained. 9. The procedure according to claim 8, indicated by the fact that the solution or solution of ammonium nitrate and ammonium sulfate is neutralized before adding limestone. 10. The method according to one of claims 8 or 9, indicated by the fact that the solution of ammonium nitrate and ammonium sulfate is a solution of double salts produced by neutralizing sulfuric acid with ammonia in the presence of ammonium nitrate. 11. The method according to at least one of claims 8 to 10, indicated by the fact that the method is integrated into the device for the continuous production of complex fertilizers using the nitro-phosphate method. 12. The method according to at least one of claims 8 to 11, indicated by the fact that limestone is added to the solution of ammonium nitrate and ammonium sulfate in two steps, whereby one part of the limestone is added to the mixer, and the other part of the limestone in the next stage of the process, to the granulation apparatus. 13. The method according to at least one of claims 8 to 11, characterized by the fact that the entire limestone is added in one step to the granulation apparatus. 14. The method according to at least one of the requirements 8 to 13, indicated by the fact that limestone and ammonium sulfate in a solid state are added to the ammonium nitrate solution and that the fertilizer is formed by compression between rotating rollers. 15. The method according to at least one of claims 8 to 14, characterized in that the granulation of the suspension, which contains limestone, is carried out by spraying on the granulation layer in a rotating drum.