Fertilizers containing slow and fast release sources of boron
By combining immediate-release and slow-release boron sources in fertilizers, the problems of uneven boron supply and toxicity are solved, achieving uniform supply and improved utilization of boron during the plant growing season.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- MOSAIC CO
- Filing Date
- 2018-03-30
- Publication Date
- 2026-06-09
Smart Images
Figure CN122167211A_ABST
Abstract
Description
[0001] This application is a divisional application. The international application number of its parent application is PCT / US2018 / 025499, the Chinese national application number is 201880026558.3, the application date is March 30, 2018, and the invention title is "Fertilizer Containing Slow-Release and Fast-Release Boron Sources".
[0002] Related Applications
[0003] This application claims the benefit of U.S. Provisional Application No. 62 / 479,948, filed March 31, 2017, the entire contents of which are incorporated herein by reference. This application also relates to U.S. Patent No. 9,266,784, which claims the benefit of U.S. Provisional Application No. 61 / 514,952, filed August 4, 2011, the entire contents of which are incorporated herein by reference. Technical Field
[0004] This invention generally relates to fertilizer compositions. More specifically, this invention relates to introducing at least two different boron sources into macronutrient carrier fertilizers as a means to enable plants to acquire boron more promptly. Background Technology
[0005] Essential plant nutrients can be divided into two groups: major and minor macronutrients and micronutrients. Plants obtain major nutrients, including nitrogen, phosphorus, and potassium, from the soil; therefore, these constitute the main part of fertilizers used to replenish soils lacking these nutrients.
[0006] According to conventional fertilizer standards, the chemical composition or analysis of fertilizers is expressed as percentages (by weight) of the essential major nutrients nitrogen, phosphorus, and potassium. More specifically, when expressing a fertilizer formulation, the first value represents the percentage of nitrogen, expressed as "total nitrogen" (N) in elemental form; the second value represents the percentage of phosphorus, expressed as "available phosphate" (P2O5) in oxide form; and the third value represents the percentage of potassium, also expressed as "available potassium oxide" (K2O), or other expressions known as (N-P2O5–K2O).
[0007] Although the amounts of phosphorus and potassium are expressed in their oxide forms, technically, fertilizers do not contain P₂O₅ or K₂O. Phosphorus is most commonly found as monocalcium phosphate, but also as other calcium phosphates or ammonium phosphate. Potassium is typically found as potassium chloride or potassium sulfate. The conversion from the oxide forms of P and K to their elemental expressions (NPK) can be performed using the following formula:
[0008] %P = %P2O5 x 0.437 %K=% K2O x 0.826
[0009] %P2O5= %P x 2.29 %K2O = %K x 1.21
[0010] In addition to the major nutrients that plants obtain through fertilization of the soil, minor and micronutrients are also essential for plant growth. These are required in much smaller quantities than major nutrients. Minor nutrients include sulfur (S), calcium (Ca), and magnesium (Mg). Micronutrients include, but are not limited to, boron (B), zinc (Zn), manganese (Mn), nickel (Ni), molybdenum (Mo), copper (Cu), iron (Fe), and chlorine (Cl).
[0011] Boron deficiency is a major problem in many agricultural regions, particularly in sandy soils, among micronutrients. Applying boron as fertilizer presents challenges due to the narrow window between nutrient deficiency and toxicity. Because plants are highly sensitive to boron and require only very small amounts, the amount of boron available to the plant's root zone must be carefully considered. The presence of high concentrations of boron can lead to the risk of seedling damage due to boron toxicity. Traditional methods of integrally mixing boron with fertilizer granules (such as borax) are ineffective or unsuitable due to uneven boron distribution, potentially resulting in excessively high boron concentrations near the granules and insufficient concentrations further away.
[0012] To help ensure uniform distribution of boron, the applicant of this application proposes, as described in U.S. Patent No. 9,266,784, to add different boron sources to potassium chloride (MOP) granules before or during compaction, thereby reducing the occurrence of boron toxicity and providing uniform application of small amounts of boron required by plants.
[0013] Another challenge in boron fertilizer management is providing adequate boron at all stages of plant growth, as this micronutrient plays a crucial role from seedling to flowering. Commonly used soluble boron sources (e.g., sodium tetraborate) are highly water-soluble and, because they are generally uncharged in most soils, tend to be extremely mobile in the soil compared to most other nutrients (except nitrates and sulfates). Therefore, soluble boron sources readily leach from the soil (especially in rainy environments) before being absorbed by the roots, leading to boron deficiency later in the growing season, particularly during flowering. Thus, balancing the provision of appropriate concentrations of boron to ensure plants receive the necessary nutrients throughout the growing season while minimizing boron toxicity is challenging.
[0014] There is still a need for a boron fertilizer product with both immediate and slow-release properties to ensure that boron is evenly and adequately distributed to the root zone of plants, while reducing the risk of boron toxicity. Summary of the Invention
[0015] Embodiments of the present invention include NPK fertilizer products having at least two boron sources with different release rates or characteristics. In embodiments, the NPK fertilizer product may comprise a macronutrient carrier, including nitrogen-based fertilizers (e.g., urea), potassium-based fertilizers (e.g., potassium hydroxide or potassium chloride (MOP)), or phosphate-based fertilizers (e.g., monoammonium phosphate or diammonium phosphate (MAP or DAP)). In one embodiment, the first boron source is highly soluble and therefore an immediate-release boron source available to plants in the early part of the growing season. The second boron source has lower solubility than the first source and is therefore a slow-release boron source relative to the first source, and is available to plants in the later part of the growing season. The two boron sources ensure a more uniform and sustained release of boron than a single source, thereby increasing the utilization of boron in the plant root zone during the growing season while reducing or eliminating the risk of boron toxicity and seedling injury.
[0016] The first boron source may include a highly soluble or immediate-release source, such as a sodium-based or acidic boron source comprising sodium tetraborate (i.e., borax) and / or boric acid, while the second boron source may include a source with significantly lower solubility than the first source, such as a calcium-based boron source comprising calcite (CaB3O4(OH)3.(H2O)) and / or boron phosphate (BPO4). For phosphate fertilizers, a preferred slow-release boron source is boron phosphate. Specifically, for boron phosphate, in embodiments, the solubility can be adjusted by heating the reaction product of phosphoric acid and boric acid to different temperatures. Another boron source may be included, with a solubility less than the first source but greater than the second source, for example, sodium borate (NaCaB5O6(OH)6.5(H2O)), which can be used as an immediate-release source when combined with a slow-release boron source, or as a slow-release source when combined with an immediate-release boron source.
[0017] Fertilizer products may optionally contain one or more additional micronutrient and / or minor nutrient sources, such as, but not limited to, micronutrients including additional sources of boron (B), zinc (Zn), manganese (Mn), molybdenum (Mo), nickel (Ni), copper (Cu), iron (Fe), and / or chlorine (Cl), and / or minor nutrients including sources of sulfur (S) in elemental form, sulfur in oxidized sulfate form (SO4), magnesium (Mg), and / or calcium (Ca), or any combination thereof at various concentrations. In the case of compaction materials, the fertilizer may also include compaction aids, colorants, and / or one or more binding components, such as sodium hexametaphosphate (SHMP).
[0018] According to one embodiment of the invention, where the carrier comprises a bonded MOP fertilizer, the fertilizer product is prepared by compacting an MOP feedstock with at least two boron sources. In another embodiment of the invention, the fertilizer comprises a granular or particulate nitrogen- or phosphate-containing carrier formed by a standard granulation process in which a boron source is added to the granulation or pelletizing line.
[0019] The above overview of the present invention is not intended to describe every illustrative embodiment or implementation of the invention. The following detailed description illustrates these embodiments in more specific terms. Attached Figure Description
[0020] The subject matter of the invention can be more fully understood in light of the following detailed description of various embodiments, taken in conjunction with the accompanying drawings, wherein:
[0021] Figure 1 A perfusion cell assembly for analyzing boron leached from soil is shown according to an embodiment of the present invention.
[0022] Figure 2 It is a graph showing the weight percentage of boron released as a function of pore volume (i.e., the time series of boron leaching) in the infusion tank assembly according to an embodiment of the present invention for various formulations.
[0023] Figure 3 This is a potted plant test assembly for analyzing boron utilization according to an embodiment of the present invention;
[0024] Figure 4 This is a graph comparing boron uptake / pot and boron leaching (as a percentage of added boron) versus water-soluble boron (as a percentage of total boron) in leaching treatments within a potted test setup.
[0025] Figure 5 This is a graph comparing boron uptake per pot for each formulation in a potted plant test setup;
[0026] Figure 6 This is a graph depicting boron uptake / pot in leached or non-leached pots for six fertilizer treatments in a potted plant test assembly;
[0027] Figure 7 This involves a side-by-side comparison of rapeseed plants with different formulations grown in pre-soaked pots and those grown in non-soaked pots within a potted plant test assembly according to the embodiment; and
[0028] Figure 8 This is a process flow diagram for compacting the circuit according to the implementation method.
[0029] While the invention is readily adaptable to various variations and alternatives, specific forms of which have been shown with the aid of examples in the accompanying drawings and will be described in more detail, it should be understood that the invention is not intended to be limited to the specific embodiments described. Rather, it is intended to cover all variations, equivalents, and alternatives falling within the spirit and scope of the invention. Detailed Implementation
[0030] Embodiments of the present invention include NPK fertilizer products having at least two boron sources with different release rates or characteristics to tailor boron utilization throughout the plant’s growing season while reducing the risk of boron toxicity.
[0031] In implementation, NPK fertilizer products may include macronutrient carriers, which include nitrogen-based fertilizers (e.g., urea), potassium-based fertilizers (e.g., potassium hydroxide or potassium chloride (MOP)), or phosphate-based fertilizers (e.g., monoammonium phosphate or diammonium phosphate (MAP or DAP)). Regarding the MOP carrier, the MOP fertilizer base may be any of a variety of commercially available MOP sources, such as, but not limited to, MOP feedstocks with a K2O content ranging from about 20% to about 80% by weight, more particularly about 48% to 62% by weight, and more particularly about 55% to 62% by weight.
[0032] In one embodiment, the first boron source is highly soluble and therefore an immediate-release boron source. The second boron source has a lower solubility than the first source and is therefore a slow-release boron source. The first boron source may include a highly soluble or immediate-release source, such as a sodium-based boron source including sodium tetraborate (i.e., borax), while the second boron source may include a source with significantly lower solubility than the first source, such as a calcium-based boron source including calcium borate (CaB3O4(OH)3.(H2O)) and / or boron phosphate (BPO4). Specifically, for boron phosphate, in an embodiment, the solubility can be tailored by heating the reaction product of phosphoric acid and boric acid to different temperatures and maintaining those temperatures for different time periods.
[0033] Another boron source with a solubility less than the first source and greater than the second source may include, for example, sodium borate (NaCaB5O6(OH)6.5(H2O)), and may be used as an immediate-release source when combined with a slow-release boron source, or as a slow-release source when combined with an immediate-release boron source. Table 1 shows the solubility of the selected borate compounds.
[0034] Table 1. Solubility of different boron sources:
[0035]
[0036] In the embodiments, the presence of at least two boron sources is such that about 0.001 wt% to about 1.0 wt%, more particularly about 0.1 wt% to about 0.7 wt% of B, and more particularly about 0.3 wt% to about 0.6 wt%, is delivered to the fertilizer granules. The ratio of immediate-release boron to slow-release boron can be, for example, 5:1, 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4, or 1:5, or any of a variety of ratios tailored to the needs of the plants.
[0037] In the case of bonded, compacted granules, fertilizer products may also include one or more binders or ingredients to improve the strength or handling capacity of the final product, making the granules less likely to abrade or disintegrate during handling or transportation, as described in U.S. Patent No. 7,727,501 (titled "Compacted granular potassium chloride, and method and apparatus for production of the same," the entire contents of which are incorporated herein by reference). Binders are chemical substances added to the feed of a compaction line to improve the strength and quality of the compacted granules. Binders act to isolate or chelate impurities in the fertilizer feedstock while providing adhesion to the compacted blend. Binders may include, for example, sodium hexametaphosphate (SHMP), tetrasodium pyrophosphate (TSPP), tetrapotassium pyrophosphate (TKPP), sodium tripolyphosphate (STPP), diammonium phosphate (DAP), monoammonium phosphate (MAP), granular monoammonium phosphate (GMAP), potassium silicate, sodium silicate, starch, dextran, lignin sulfonate, bentonite, montmorillonite, kaolin, or combinations thereof. As a supplement or alternative to binders, certain micronutrients can themselves act as binders to improve particle strength.
[0038] According to an embodiment of the invention, a first boron source having a first solubility and a second boron source having a lower solubility than the first source are blended into the main nutrient feed of a compaction circuit to prepare a binder granular NPK fertilizer product containing at least two boron sources. The boron sources may be added to the feed before compaction, or they may be added separately to the feed, or they may be blended as a whole before being added to the feed. The blended raw material is compacted and then subjected to conventional further processing (e.g., crushing and size grading) to produce binder fertilizer particles containing at least two boron sources, which are uniformly distributed throughout the granular product.
[0039] A production line or line for producing compacted granular fertilizer compositions typically includes a feed device, such as a belt conveyor or pneumatic conveyor, that conveys various granular major nutrient streams, sieved material, recycled or waste material, a first boron source and a second boron source, one or more optional minor and / or micronutrients, and one or more optional binders into a compactor. The compactor then forces the feed into a bonded intermediate sheet or cake under high pressure, which can then be crushed, graded, resized, or otherwise reprocessed into the desired finished granular product containing at least two boron sources.
[0040] Figure 8 This is a flowchart illustrating the steps involved in a proposed embodiment of the production method of the present invention. Specifically, Figure 8This demonstrates how boron sources can be blended into or injected separately into the main nutrient feed of the production line. The boron source can be added to the feed at different locations in the line using one or more syringes (including metering devices) to allow for more precise control over the amount of each component added per unit of feed.
[0041] After the boron source and optional binder are added to the feed, the additives and feed are blended. The blending step can be carried out passively by agglomerating these materials, or it can be done by the feeding mechanism during its combined transport, or alternatively, specific blending equipment can be added to the production line between the syringe and the compactor to more actively or proactively blend the boron source, optional binder, optional other additives and raw materials prior to compaction.
[0042] The feedstock is then appropriately mixed with a boron source and optional other additives, and then compacted. The compaction process can be carried out using conventional compaction equipment such as a roller compactor. Then, as... Figure 8 As shown, the resulting agglomerated intermediate composition can be further processed into the desired finished granular product using methods suitable for producing the desired particle size or type of final product, such as crushing, sieving, or other conventional grading methods.
[0043] It will be understood that variations in the accompanying processes or equipment that allow the addition of one or more additional micronutrients, minor nutrients and / or binders to the raw materials, either simultaneously or separately, are contemplated within the scope of this invention.
[0044] The following examples further illustrate the implementation of this application.
[0045] Example
[0046] Experiment 1: Column dissolution
[0047] MOP fine powder was compacted with different proportions of boron (from borax and hard borate) to achieve a total boron content of approximately 0.5% by weight of the fertilizer granules. Different ratios of boron supplied as borax and hard borate were 1:0 (i.e., no hard borate), 1:1, 1:3, and 0:1 (i.e., no borax). Boron dissolution from the granules was measured over 72 hours using column infusion technology. (Reference) Figure 1 The column infusion technique uses an infusion pool assembly 100 in which a known weight of fertilizer 102 is buried in a volume of soil 104 within a vertical column pool 106. Leachate S is pumped from bottom to top through a glass wool barrier 108, followed by soil 104, which surrounds the fertilizer sample 102 and a portion of acid-washed sand 104a. The top 103 includes filter paper 110 to prevent soil removal along with the collected leachate 112.
[0048] In this specific infusion example, a 1-gram sample of fertilizer product was buried in a soil column. The leachate was 10 mM CaCl2 with a pH of approximately 6 and was introduced into the column at a flow rate of 10 mL / h.
[0049] The results of the infusion technique are shown in Figure 2 The figure shows the weight percentage of boron released (i.e. captured in the leachate) for each composition, indicating that the immediate and sustained release characteristics can be adjusted by changing the ratio of borax to calcareous borosilicate.
[0050] Experiment 2: Pot Experiment
[0051] Pot experiments were conducted using rapeseed plants, a MOP fertilizer control (boron-free), and the same four fertilizer formulations used in Experiment 1, comprising MOP containing 0.5% boron and different proportions of immediate-release boron (borax) and slow-release boron (calcium borate) (Table 2). Soil consisted of 1 kg / pot of sandy loam from Mt. Compass, the chemical analysis of which is listed in Table 3 below. Boron sources were added at an equivalent rate of 1.5 kg boron / ha, equivalent to 0.9 mg boron and 86.6 mg K / 1 kg pot. Each fertilizer treatment was replicated five times.
[0052] Table 2: Comparison of Acid Extractability and Water Extractability B
[0053]
[0054] Table 3. Selected characteristics of South Australian soils used in the experiment
[0055]
[0056] In this experiment, 30 pots were soaked before planting the rapeseed crop, while 30 pots were not soaked. (Reference) Figure 3 Leaching was performed in leaching pot 300 by applying four-well volume 302 (or 350 mL x 4) of demineralized water to 1 kg of soil 304 (with MOP fertilizer 306 applied 1 cm below the surface of soil 304). Boron in the leachate 308 captured at the bottom of pot 300 was analyzed. The amount of boron leached from pot 300 decreased with increasing amounts of slow-release boron in the fertilizer. Figure 4 Then, rapeseed crops were planted and allowed to grow for approximately twelve weeks, after which the boron concentration in the plant buds was analyzed. Figure 7 As shown, the non-leaching basin 700 under different formulations grows faster than the leaching basin 702 under the same formulation.
[0057] As shown in Table 2 and Figure 2As shown in column irrigation, 4 (pot experiment), 5 (pot experiment), and 6 (pot experiment), in both column irrigation and pot experiment techniques, it was observed that as the percentage of water-soluble boron increased, the release rate of boron increased, the amount of boron taken up by the plant decreased, and the effect on acid-extractable K was minimal.
[0058] Specific reference Figure 6 Boron uptake per pot was measured after twelve weeks. In non-leached pots, the boron fertilizer formulation had no consistent effect on boron uptake. For leached pots, boron uptake by plants increased with increasing amounts of slow-release boron from calcium borate in the fertilizer formulation.
[0059] These experiments have established that a balance between slow-release and immediate-release boron can improve boron uptake, and that adding a slow-release boron source to macronutrient fertilizers can provide an excellent boron supply in the leaching environment during the plant growing season.
[0060] Various embodiments of the systems, apparatus, and methods have been described herein. These embodiments are given by way of example only and are not intended to limit the scope of the claimed invention. Furthermore, it should be understood that the various features of the described embodiments can be combined in various ways to produce many other embodiments. In addition, while various materials, sizes, shapes, configurations, and positions have been described for use with the disclosed embodiments, other materials, sizes, shapes, configurations, and positions besides those disclosed may be used without departing from the scope of the claimed invention.
[0061] Those skilled in the art will recognize that the subject matter herein may include fewer features than those shown in any of the embodiments described above. The embodiments described herein are not intended as an exhaustive representation of the various ways in which the various features of the subject matter may be combined. Therefore, embodiments are not mutually exclusive combinations of features; rather, various embodiments may include combinations of different features selected from different embodiments, as understood by those skilled in the art. Furthermore, unless otherwise stated, elements described with respect to one embodiment may also be implemented in other embodiments, even if not described in such embodiments.
[0062] While dependent claims may refer in the claims to specific combinations with one or more other claims, other embodiments may also include combinations of dependent claims with the subject matter of each other's dependent claims, or combinations of one or more features with other dependent or independent claims. Such combinations are presented herein unless it is stated that no particular combination is intended.
[0063] Any inclusion by reference to the foregoing document is limited to the absence of any subject matter contrary to the express disclosure herein. Any inclusion by reference to the foregoing document is further limited to the absence of any claims contained in the document being incorporated herein by reference. Any inclusion by reference to the foregoing document is further limited to the absence of any definitions provided in the document being incorporated herein by reference unless expressly included herein.
[0064] For the purposes of interpreting the claims, it is explicitly intended that the provisions of Section 112(f) of Title 35 of the USC not be invoked unless the specific terms “means for…” or “steps for…” are recited in the claims.
Claims
1. A granular fertilizer composition comprising granules formed from a compacted potassium chloride composition, said potassium chloride composition comprising: Potassium chloride containing 48% to 62% by weight of K₂O; A first boron source having a first solubility, wherein the first boron source is sodium tetraborate; and A second boron source having a second solubility lower than the first solubility. The first and second boron sources are distributed throughout the granular fertilizer composition. The first boron source is configured to be released from the particles at a faster rate than the second boron source, and The fertilizer composition is formed into granules.
2. The granular fertilizer composition according to claim 1, wherein, The second boron source includes calcite and / or boron phosphate.
3. The granular fertilizer composition according to claim 1, wherein, The first and second boron sources are present in the fertilizer granules in an amount providing a total of 0.001 wt% to 1.0 wt% B.
4. The granular fertilizer composition according to claim 3, wherein, The first and second boron sources are present in a total amount of B of 0.1% to 0.7% by weight.
5. The granular fertilizer composition according to claim 4, wherein, The first and second boron sources are present in a total boron content of 0.3% to 0.6% by weight.
6. The granular fertilizer composition according to claim 1, wherein, The ratio of the first boron source to the second boron source is selected from: 5:1, 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4 or 1:
5.
7. A method for forming a granular fertilizer product containing multiple boron sources, the method comprising: A fertilizer composition containing a major nutrient source is provided, the major nutrient source comprising potassium chloride containing 48% to 62% K2O; a first boron source having a first solubility; and a second boron source having a second solubility less than that of the first boron source; wherein the first boron source is sodium tetraborate; Compact the fertilizer composition; and The compacted fertilizer composition is broken into fertilizer granules. The first boron source is configured to be released from the particles at a faster rate than the second boron source.
8. The method according to claim 7, wherein, The second boron source includes borate and / or boron phosphate (BPO4).
9. The method according to claim 7, wherein, The first and second boron sources are present in the fertilizer granules in an amount providing a total of 0.001 wt% to 1.0 wt% B.
10. The method according to claim 9, wherein, The first and second boron sources are present in a total amount of B of 0.1% to 0.7% by weight.
11. The method according to claim 10, wherein, The first and second boron sources are present in a total boron content of 0.3% to 0.6% by weight.
12. The method according to claim 7, wherein, The ratio of the first boron source to the second boron source is selected from: 5:1, 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4 or 1:
5.
13. The method of claim 7, further comprising: The particles of the bonded MOP product are graded by size.
14. The method of claim 7, further comprising: Provide micronutrients other than boron, wherein at least one micronutrient is selected from the group consisting of zinc (Zn), manganese (Mn), molybdenum (Mo), nickel (Ni), copper (Cu), sulfur in elemental form (S), sulfur in oxidized sulfate form (SO4), and combinations thereof.
15. The method according to claim 7, wherein, Each boron source was blended together, then added to the primary nutrient source and compacted.
16. The method according to claim 7, wherein, Each of the first and second boron sources is added to the primary nutrient source, and then compaction is performed.
17. The method of claim 7, further comprising adding an adhesive prior to compaction.
18. The method according to claim 17, wherein, The adhesive is selected from the group consisting of sodium hexametaphosphate (SHMP), tetrasodium pyrophosphate (TSPP), tetrapotassium pyrophosphate (TKPP), sodium tripolyphosphate (STPP); diammonium phosphate (DAP), monoammonium phosphate (MAP), granular monoammonium phosphate (GMAP), potassium silicate, sodium silicate, starch, dextran, lignin sulfonate, bentonite, montmorillonite, kaolin, or combinations thereof.