Particulate matter of polyhalite and urea
阅读说明：本技术 杂卤石和尿素的颗粒物 (Particulate matter of polyhalite and urea ) 是由 K·阿布-拉比亚 N·盖因克 于 2020-08-24 设计创作，主要内容包括：本文提供了包含尿素、杂卤石和硫酸铵的肥料颗粒物。(Provided herein are fertilizer granules comprising urea, polyhalite, and ammonium sulfate.)
1. A fertilizer granule comprising urea, polyhalite and ammonium sulfate.
2. The particulate matter of claim 1, further comprising potash, magnesite, and clay.
3. The particulate matter of claim 2, wherein the potash is in the form of potassium chloride (MOP).
4. A particulate matter according to claim 1, wherein the urea is present in a concentration of 40-50% w/w, the polyhalite is present in a concentration of 15-30% w/w and the ammonium sulphate is present in a concentration of 5-15% w/w, all by weight of the particulate matter.
5. A particulate matter according to claim 4, wherein the urea is present in a concentration of 45% w/w, the polyhalite is present in a concentration of 23% w/w and the ammonium sulphate is present in a concentration of 10% w/w, by weight of the particulate matter, introduced as ammonia and sulphuric acid.
6. The particulate matter of claim 5, wherein the strength of the particulate matter is 3.8 KgF/particulate matter when measured after production.
7. A particulate material according to claim 6, wherein the particle size distribution of the particulate material is from 2.0mm to 4.75 mm.
8. A process for producing a fertilizer comprising:
mixing a feed of polyhalite with a feed of urea, magnesite, clay, and sulfuric acid to produce a mixture;
adding ammonia to the mixture, which causes a chemical reaction between the ammonia and the acidic compound to produce an exothermic reaction with a temperature increase; the exothermic reaction causes the urea to melt, thereby providing a mixture with molten urea;
granulating the mixture with the molten urea in a drum granulator to produce a particulate material;
the particulate material is sieved in a sieving machine to produce three different fractions of different sizes: oversized granules subjected to a comminution process and returned to the granulator as recycle, granulated granules of the desired size transferred for coating and fine granules transferred back to the mixture.
9. The process of claim 8, wherein the exothermic reaction exceeds 130 degrees celsius.
10. The particulate matter of claim 1 comprising a core and one or more coating layers.
11. The particulate matter of claim 10, wherein the urea, polyhalite, and ammonium sulfate are contained in the core.
Technical Field
The present invention relates to the field of fertilizers, in particular to the prilling production of urea and polyhalite as fertilizers.
Background
For normal growth, plants require nutrients (nitrogen, potassium, calcium, zinc, magnesium, iron, manganese, etc.) that can normally be found in soil. Fertilizers are sometimes needed to achieve the desired plant growth, as these fertilizers can enhance the growth of the plant.
This plant growth is satisfied in two ways, the traditional way being to provide additives to nutrients. A second mode in which certain fertilizers function is to enhance the effectiveness of the soil by improving the water retention (water retention) and aeration (aeration) of the soil. Fertilizers typically provide three major macronutrients (macronutrients) in varying proportions:
nitrogen (N): leaf growth;
phosphorus (P): development of roots, flowers, seeds, fruits;
potassium (K): vigorous stem growth, movement of water in the plant, promotion of flowering and fruiting;
three minor macronutrients: calcium (Ca), magnesium (Mg) and sulfur (S);
micronutrient: copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), zinc (Zn), boron (B), and occasionally silicon (Si), cobalt (Co) and vanadium (V) plus rare mineral catalysts.
The most reliable and efficient way to reconcile the availability of nutrients with plant needs is to control the release of nutrients into the soil solution by using slow release fertilizers (slow release fertilizers) or controlled release fertilizers (controlled release fertilizers).
Both Slow Release Fertilizers (SRF) and Controlled Release Fertilizers (CRF) are supplied with nutrients gradually. However, slow release fertilizers and controlled release fertilizers differ in many ways: their technique used, release mechanism, lifetime, release control factors, etc.
Solid fertilizers include granules (granules), pellets (grains), crystals and powders. Granular fertilizers (granulated fertiliser) are a type of granular fertilizer that is made to approximate a spherical shape by solidifying free falling droplets in air or a fluid medium. Most Controlled Release Fertilizers (CRF) used in commercial nurseries are small granular fertilizers that have been coated with sulfur or polymers. These products have been developed to allow slow release of nutrients into the root zone throughout crop development.
Polyhalite is an evaporite mineral having the formula: k2Ca2Mg(SO4)4 2H2Hydrated sulfates of potassium, calcium and magnesium of O. Polyhalite is used as a fertilizer because it contains four important nutrients and the chlorides are low:
48％SO3calculated as sulphate
14％K2O
6％MgO
17％CaO。
Nitrogen is an essential component of plants. N-containing fertilizers such as urea, ammonium nitrate, ammonium sulfate, calcium nitrate and magnesium nitrate are useful for the growth of plants.
Urea, also known as carbamide (carbomide), is of the formula CO (NH)2)2The organic compound of (1). Such amides have two-NH groups linked via a carbonyl (C ═ O) functionality2A group.
Although polyhalite and urea are useful for normal growth of plants, in practice the two are not miscible because urea is considered a ductile material and polyhalite is a mined non-ductile material. From a chemical point of view, it is extremely difficult to cause adhesion of these two substances without the use of shear forces, since these are solids.
WO2017081470 discloses a fertilizer granule comprising: a first region of a fertilizer composition that provides nitrogen; and a second zone adhered to the exterior of the first zone, the second zone comprising a fertilizer composition capable of providing (a) two or more alkali and/or alkaline earth nutrients and (b) sulfur.
However, WO2017081470 recognizes that it is difficult to adhere urea and polyhalite together, and only teaches a process of coating polyhalite on top of a core comprising urea.
Summary of The Invention
According to certain illustrative embodiments, provided herein is a fertilizer granule comprising urea, polyhalite, and ammonium sulfate.
According to certain illustrative embodiments, the particulate matter may include a core and one or more coating layers.
According to certain embodiments, urea, polyhalite, and ammonium sulfate may be included in the core.
According to certain embodiments, the particulate matter may also comprise potash, magnesite, and clay.
According to certain embodiments, the Potash may be in the form of potassium chloride (MOP).
According to certain embodiments, urea may be present in a concentration of 40% w/w to 50% w/w, preferably 45% w/w, of the weight of the particulate matter, polyhalite may be present in a concentration of 15% w/w to 30% w/w, preferably 23% w/w, of the weight of the particulate matter, and ammonium sulfate may be present in a concentration of 5% w/w to 15% w/w, preferably 10% w/w, of the weight of the particulate matter.
According to certain embodiments, the strength of the granules of the invention may be 3.8 KgF/granule, when measured after production.
According to certain embodiments, the Particle Size Distribution (PSD) of the particles of the invention can be from 2.0mm to 4.75 mm.
According to certain illustrative embodiments, provided herein is a process for pelletizing polyhalite and urea, where the process may include reacting ammonia with sulfuric acid, thereby causing a chemical reaction that melts the urea.
According to certain embodiments, the process may comprise:
mixing a feed of polyhalite with a feed of urea, magnesite, clay, and an acidic compound to produce a mixture;
ammonia is added to the mixture, which causes a chemical reaction between the ammonia and sulfuric acid to produce an exothermic reaction with a temperature increase (over 110 degrees celsius). The exothermic reaction causes the urea to melt, thereby providing a mixture with molten urea;
granulating the mixture with molten urea in a drum granulator to produce a particulate material;
the particulate material is sieved in a sieving machine to produce three different fractions of different sizes: oversized granules (oversized granules) which undergo a comminution process and are returned to the granulator as recycle, granulated granules of the desired size which are transferred for coating and fine granules which are transferred back to the mixture.
Detailed Description
According to certain illustrative embodiments, provided herein is a fertilizer granule comprising urea, polyhalite, and ammonium sulfate.
According to certain illustrative embodiments, the term "fertilizer" may include any natural or synthetic source of material that may be applied to soil or plant tissue to supply one or more plant nutrients necessary for plant growth, including, for example, mono-nutrient ("elemental") fertilizers, such as ammonium nitrate, urea, calcium ammonium nitrate (calcium ammonium nitrate), superphosphates (superphosphates) such as "Single superphosphates" (SSP), phosphogypsum, Triple Superphosphates (TSP), or mixtures thereof; multi-nutrient fertilizers, such as binary (NP, NK, PK) fertilizers, e.g., monoammonium phosphate (MAP) and/or diammonium phosphate (DAP), NPK fertilizers that provide a three-component fertilizer of nitrogen, phosphorus, and potassium; fertilizers containing one or more of the primary micronutrient sources of iron, manganese, boron, molybdenum, zinc, and copper, and the like; compound fertilizers, for example, comprising N, P and K; organic fertilizers such as peat, animal waste, plant waste from agriculture, and sewage sludge; and/or other elements such as calcium, magnesium and sulfur.
According to certain illustrative embodiments, provided herein is a fertilizer granule comprising urea, polyhalite and ammonium sulfate, wherein the urea, polyhalite and ammonium sulfate are mixed together.
According to certain illustrative embodiments, the fertilizer granules may include a core and one or more coating layers. According to certain embodiments, the core may comprise urea, polyhalite, and ammonium sulfate.
According to certain embodiments, the particulate matter may also comprise potash, magnesite, and clay.
Magnesite allows magnesium to be present in the final product, where magnesium is beneficial for the growth of plants.
According to certain illustrative embodiments, the clay may be present at a concentration of 5% w/w to 20% w/w, preferably 15% w/w,
according to certain illustrative embodiments, the magnesite may be present in a concentration of 0.5% w/w to 3% w/w, preferably 1% w/w, of the weight of the particulate matter.
According to certain illustrative embodiments, the granules of the invention may further comprise a conditioning agent. According to certain embodiments, the modulator may be present at a concentration of 1% w/w to 5% w/w of the weight of the particulate matter.
According to certain embodiments, the potash may be in the form of potassium chloride (MOP). Potassium chloride (refer to Potassium chloride), also known as Potassium chloride (potassium chloride), contains 60% potassium and can be preferably used to correct K2O。
According to certain embodiments, urea may be present in a concentration of 40% w/w to 50% w/w, preferably 45% w/w, of the weight of the particulate matter, polyhalite may be present in a concentration of 15% w/w to 30% w/w, preferably 23% w/w, of the weight of the particulate matter, and ammonium sulfate may be present in a concentration of 5% w/w to 15% w/w, preferably 10% w/w, of the weight of the particulate matter.
According to certain embodiments, the strength of the granules of the invention may be 3.8 KgF/granule, when measured after production.
According to certain embodiments, the Particle Size Distribution (PSD) of the particles of the invention can be from 2.0mm to 4.75 mm.
According to certain illustrative embodiments, provided herein is a process for granulating polyhalite and urea, wherein the process may include exposing urea ammonia and an acidic component, such as sulfuric acid, to cause a chemical reaction that forms an ammonium salt.
According to certain embodiments, the process may comprise:
mixing a feed of polyhalite with a feed of urea, magnesite, clay, and sulfuric acid to produce a mixture;
adding ammonia to the mixture, which causes a chemical reaction that melts the urea, thereby providing a mixture with molten urea;
granulating the mixture with molten urea in a drum granulator to produce a particulate material;
the particulate material is sieved in a sieving machine to produce three different fractions of different sizes: oversized granules subjected to a comminution process and returned to the granulator as recycle, granulated granules of the desired size transferred for coating and fine granules transferred back to the mixture.
According to certain illustrative embodiments, the present invention allows for the efficient granulation of polyhalite and urea.
According to certain embodiments, the process of the present invention allows for chemical melting of urea, resulting in effective adhesion of urea to polyhalite within the produced particulate matter.
H2SO4+2NH3→(NH4)2SO4
According to certain embodiments, oil may be added to the produced particulates, for example, to improve the rheology of the product and reduce dust formation. For example, an amount of anti-caking agent, coating agent (coating agent) may be added. According to certain embodiments, any suitable oil may be used, including, for example, mineral oil or the like, slack wax (slack wax) or the like, paraffin wax or the like, or mixtures thereof.
According to these embodiments, in wet granulation, the process comprises the following steps:
mixing urea, polyhalite, magnesite, clay, sulfuric acid and water at room temperature; ammonia is added to produce ammonium sulfate. According to these embodiments, the reaction between sulfuric acid and ammonia gives off heat to melt part of the urea.
Feeding the mixture to a granulator to provide wet granules; drying the particles and sieving the particles.
According to certain embodiments, after sieving, there are three types of effluents:
1. particles of desired size-from 2mm to 4.75mm
2. Oversized (OS) particles-are returned to the grinding stage, e.g. between 4% and 20% of the output.
3. Undersized (US) flakes-are returned to granulation.
4. According to certain embodiments, an anti-caking agent is added.
According to certain embodiments, the nutrients may include:
nitrogen (N): leaf growth;
potassium (K): vigorous stem growth, movement of water in the plant, promotion of flowering and fruiting.
Three minor macronutrients: calcium (Ca), magnesium (Mg) and sulfur (S);
micronutrient: copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), zinc (Zn), boron (B), and occasionally silicon (Si), cobalt (Co) and vanadium (V) plus rare mineral catalysts.
According to certain embodiments, the mixture of the invention may also comprise other fertilizers besides urea, ammonium salts and polyhalite.
According to certain illustrative embodiments, the sieving is performed using a sieve having openings with a diameter between 1.4mm and 4.75mm, preferably between 2mm and 4.75 mm.
According to certain embodiments, mixing may be performed in a blade blender and/or any other suitable device capable of having a rotational speed and a high degree of blending that creates a swirling motion for complete homogenization.
According to certain embodiments, the resulting particulate matter may be further coated with a suitable coating. For example, the coating may include a biodegradable coating, a slow release coating, a controlled release coating, an oily coating, a wax coating, a starch coating, an anti-caking agent.
The resulting mixture may include the following properties as detailed in table 1.
TABLE 1
Example 1
Feeding of the feedstock
Material
Feed rate (ton/hour)
Ratio (%)
Polyhalite
230
23.3
Urea
447
45.2
Ammonium sulfate
100
10.1
MOP
33
3.3
Magnesite
8
0.8
Clay clay
150
15.2
Anti-caking agent
10
1
Water (W)
10
1
Urea, polyhalite, ammonium sulfate, potash, magnesite, clay conditioning agent and water are mixed and transferred to a drum granulator.
The following conditions were set:
product composition
Element(s)
Concentration of
Unit of
Total N
23.8
％
SO4
20.5
％
K2O
5
％
Ca
2.8
％
MgO
2
％
Cl
5.5
％
Insoluble substances (Insol)
15.9
％
H2O
3.7
％
pH
6.5
The products are stacked and stored under the environmental condition.
Quality after one month of production
Value of
Unit of
Strength of
3.8
Kg/granule
Abrasion of-12 meshes
0.88
％
Abraded to-32 meshes
0.35
％
Abraded to-100 meshes
0.22
％
Environmental dust
0.09
％
Although the present invention has been described in certain specific embodiments, many modifications and variations are possible. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.