GRANULES OF POLYHALITE AND PHOSPHOGYPSUM AND A PROCESS FOR THE PRODUCTION THEREOF

Abstract

There is provided herein a granule comprising Polyhalite and phosphogypsum, in a ratio of between 40:60 to 60:40, respectively.

Claims

1. A granule comprising Polyhalite and phosphogypsum, in a ratio of between 40:60 to 60:40, respectively.

2. The granule of claim 1, wherein said ratio is 50:50.

3. The granule of claim 1, further comprising a binder.

4. The granule of claim 1, further comprising at least one coating layer.

5. A method of producing the fertilizer of claim 1, comprising Mixing Polyhalite with phospogypsum in a ratio of 50:50 for 1-10 minutes to yield a mixture; Transferring said mixture to a rotating drum for 1-10 minutes to yield granules; and Drying said granules.

6. The method of claim 5, further comprising adding add one or more inorganic materials to neutralize any acidic residues formed in the process.

7. The method of claim 6, wherein said inorganic materials is phosphate rock or Calcium carbonate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0027] According to some demonstrative embodiments, there is provided herein a granule comprising Polyhalite and phosphogypsum, in a ratio of between 40:60 to 60:40, respectively.

[0028] According to some demonstrative embodiments the ratio may be 50:50. According to some demonstrative embodiments the granule may further comprise a binder.

[0029] According to some demonstrative embodiments, the granule may further comprise carbonate salts like calcium carbonate, magnesium carbonate dolomite,e.g., to neutralize the acidic character of the phosphogypsum. According to some demonstrative embodiments, combining Phosphogypsum with polyhalite may offer a solution to the environmental problem. In addition, according to some demonstrative embodiments utilizing phosphogypsum as a fertilizer may add more nutrients to the plant, like K.sub.2O,CaO MgO, and/or S.

[0030] Polyhalite is an evaporite mineral, a hydrated sulfate of potassium, calcium and magnesium with formula: K.sub.2SO.sub.4 MgSO.sub.4 2CaSO.sub.4 .Math.2H.sub.2O. Polyhalite is used as a fertilizer since it contains four important nutrients K.sub.2O, CaO MgO, S and is low in chloride.

[0031] Phosphogypsum is a by production off the reaction between sulfuric acid and phosphate rock according to the following reaction:

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[0032] However, according to some demonstrative embodiments, the fertilizer matrix, i.e., the combination of phosphogypsum with Polyhalite may increase the sulphate value of the fertilizer.

[0033] According to some demonstrative embodiments, in the mixture the ratio of the phosphogypsum and polyhalite 60:40 to 40:60, respectively, preferably 50:50.

[0034] According to some demonstrative embodiments, the granule of the present invention may optionally include a binder, for example in a concentration between 1-5% w/w.

[0035] The binder may include but not limited : for example, organic or inorganic binders, such as, starch, bentonite, sodium silicate, lignosulfonates, molasses, hydrated lime, bitumen, Portland cement, clay, acids, cellulose gum, sucrose, water, water glass, cements, Fly Ash, Potassium and Sodium Silicate, MgO, CaO, Alganite, Geo-polymers, oils and waxesand the like, or a combination thereof.

[0036] Preferably, the binder may be water, fly ash, silicate lignosulphonate or a combination thereof.

[0037] According to some embodiments, there is provided herein a method of producing the fertilizer granule disclosed herein, comprising mixing Polyhalite with phospogypsum in a ratio of 50:50 for 1-10 minutes to yield a mixture; transferring said mixture to a rotating drum for 1-10 minutes to yield granules; and drying said granules.

[0038] According to some demonstrative embodiments, the method may further comprise adding one or more inorganic materials to neutralize any acidic residues formed in the process.

[0039] According to some demonstrative embodiments, the inorganic materials may be selected from a group including phosphate rock or Calcium carbonate or a combination thereof.

Example-1

[0040] 1500 grams of polyhalite was mixed with 1500 grams of phosphogypsum for 4 minutes to yield a mixture. The mixture was transferred to a rotating drum 25 rpm for an additional 4 minutes to yield granules.

[0041] The granules were then dried. [0042] The granules PSD 2-4 mm [0043] Abrasion -12 mesh 16% [0044] Humidity content 8%. [0045] Strength 1.9 Kg/granule

[0046] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made.

[0047] It will be appreciated that various features of the invention which are, for clarity, described in the contexts of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable subcombination. It will also be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove.