Binders for the granulation of fertilizers

Abstract

According to some demonstrative embodiments, there is provided herein a fertilizer granule including a fertilizer dust and one or more binders wherein said granule comprises a single strength of at least 2.5 kg/gran and a single strength after humidity chamber 24 hours, 79% RH of at least 0.5 kg/granule.

Claims

1. A fertilizer granule comprised of potash and one or more geopolymer binders wherein said granule comprises a single strength of at least 2.5 kg/granule and a single strength after being placed in a humidity chamber for 24 hours, and having 79% RH of at least 0.5 kg/granule; wherein all of said potash in said granule consists of 100% w/w potash dust.

2. The granule of claim 1, further comprising one or more additional organic or inorganic binders.

3. The granule of claim 2, wherein said one or more additional binders is, selected from the group consisting of starch, bentonite, sodium silicate, lignosulfonates, molasses, hydrated lime, bitumen, Portland cement, clay, acids, cellulose gum, sucrose, water, water glass, cements, and combinations thereof.

4. The granule of claim 2, wherein said one or more additional binders comprises an acid selected from the group consisting of nitric, hydrochloric, phosphoric and sulphuric.

5. The granule of claim 1, further comprising micronutrients selected from the group consisting of Zn, B, Cu, Fe, and Mo.

6. The granule of claim 5, wherein said micronutrients are in a concentration between 0.1-2%.

7. The granule of claim 1, wherein said geopolymer is fly ash.

8. A process for the production of a fertilizer granule comprising: Mixing potash with a geopolymer binder to provide a fertilizer mix; Wetting the fertilizer mix with water; and Using wet granulation to form stable fertilizer granules, wherein all of said potash in said granule consists of 100% w/w potash dust.

9. The process of claim 8, wherein said geopolymer is fly ash.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) According to some demonstrative embodiments disclosed herein, there is provided a granular fertilizer composition and methods for the preparation thereof.

(2) According to some embodiments, the fertilizer composition as described herein may be in a shape of a granule and including one or more binders. According to some demonstrative embodiments, the process of preparation of the fertilizer granule may include using fine particles and/or a fertilizer dust with one or more binders of the present invention.

(3) According to some embodiments, there is provided a granule including at least one fertilizer and at least one binder which is a geopolymer or a geopolymer like material.

(4) According to some demonstrative embodiments, the granule of the present invention comprising the binder may have a strength of at least 2 kg/granule and preferably of at least 2.5 kg/granule and a strength after humidity of at least 0.2 kg/granule, preferably of at least 0.5 kg/granule, wherein after humidity refers to a granule being placed in a humidity chamber for 24 hours, and having 79% RH.

(5) According to some demonstrative embodiments, the term “fertilizer” may include any material of natural or synthetic origin that is applied to soils or to plant tissues to supply one or more plant nutrients essential to the growth of plants, including, for example, Single nutrient (“straight”) fertilizers such as Ammonium nitrate, Urea, calcium ammonium nitrate, superphosphate, e.g., “Single superphosphate” (SSP), phosphogypsum, Triple superphosphate (TSP) or a mixture thereof; Multinutrient fertilizers such as Binary (NP, NK, PK) fertilizers, e.g., monoammonium phosphate (MAP) and/or diammonium phosphate (DAP), NPK fertilizers which are three-component fertilizers providing nitrogen, phosphorus, and potassium; fertilizers which include one or more of the main micronutrients sources of iron, manganese, boron, molybdenum, zinc, and copper and the like; Compound fertilizers, e.g., which contain N, P, and K; Organic fertilizers such as peat, animal wastes, plant wastes from agriculture, and sewage sludge; and/or Other elements such as calcium, magnesium, and sulfur.

(6) According to some embodiments, the fertilizer preferably includes one or more of nitrogen fertilizers such as ammonia, anhydrous ammonium nitrate, urea and sodium nitrate; Phosphate fertilizers; Potassium fertilizers, such as Potash, potassium chloride, potassium sulfate, potassium carbonate, or potassium nitrate

(7) According to some embodiments, the fertilizer is preferably Potash, Sulfates such as, SOP, Poly-sulfates: and in some embodiments may include Micronutrients such as Zn, B, Cu, Fe, Mo in a concentrations between 0.1-2%.

(8) According to some embodiments, the fertilizer may include include 48% SO.sub.3 as sulphate, 14% K.sub.2O as from sulphate of potash, 6% MgO as from magnesium sulphate and 17% CaO as from calcium sulphate (also known as Polysulphate™).

(9) According to some embodiments, the fertilizer is preferably Potash, Phosphate and Phosphate derivatives, Calcium Phosphate, Magnesium Oxide, Ammonium Solphate, Potassium Nitrate, Potassium Solphate, Leonite, Urea, MonoamonniumPhosphate (MAP), DiAmoniumPhosphate (DAP), MonoPottasiumPhosphate (MKP).

(10) According to some embodiments, the term “geopolymers” may include, for example, any suitable inorganic materials that form long-range, covalently bonded, non-crystalline (amorphous) networks, wherein the fundamental unit within a geopolymer structure is a tetrahedral complex consisting of Si or Al coordinated through covalent bonds to four oxygens.

(11) Geopolymers comprise following molecular units (or chemical groups):

(12) —Si—O—Si—O-siloxo, poly(siloxo)

(13) —Si—O—Al—O-sialate, poly(sialate)

(14) —Si—O—Al—O—Si—O-sialate-siloxo, poly(sialate-siloxo)

(15) —Si—O—Al—O—Si—O—Si—O-sialate-disiloxo, poly(sialate-disiloxo)

(16) —P—O—P—O-phosphate, poly(phosphate)

(17) —P—O—Si—O—P—O-phospho-siloxo, poly(phospho-siloxo)

(18) —P—O—Si—O—Al—O—P—O-phospho-sialate, poly(phospho-sialate)

(19) —(R)—Si—O—Si—O—(R) organo-siloxo, poly-silicone

(20) —Al—O—P—O-alumino-phospho, poly(alumino-phospho)

(21) —Fe—O—Si—O—Al—O—Si—O-ferro-sialate, poly(ferro-sialate)

(22) Geopolymers are presently developed and applied in 10 main classes of materials:

(23) Waterglass-based geopolymer, poly(siloxonate), soluble silicate, Si:Al=1:0

(24) Kaolinite/Hydrosodalite-based geopolymer, poly(sialate) Si:Al=1:1

(25) Metakaolin MK-750-based geopolymer, poly(sialate-siloxo) Si:Al=2:1

(26) Calcium-based geopolymer, (Ca, K, Na)-sialate, Si:Al=1, 2, 3

(27) Rock-based geopolymer, poly(sialate-multisiloxo) 1<Si:Al<5

(28) Silica-based geopolymer, sialate link and siloxo link in poly(siloxonate) Si:Al>5

(29) Fly ash-based geopolymer

(30) Ferro-sialate-based geopolymer

(31) Phosphate-based geopolymer, AlPO4-based geopolymer

(32) Organic-mineral geopolymer

(33) According to some preferred embodiments, the fertilizer composition may include a mixture of Alginite of fly ash, Bentonite, Phosphate rock, a base, Metakaolin, and Water glass.

(34) According to some demonstrative embodiments of the present invention there is provided a process for the granulation of a fertilizer including mixing fertilizer dust with one or more binders to provide a core mixture and granulating the core mixture using a wet granulation to provide stable fertilizer granules.

(35) According to some embodiments, in the wet granulation, the granules may be formed by the addition of a granulation mix including the fertilizer dust and the binder onto a powder bed which is under the influence of an impeller (in a high-shear granulator), screws (in a twin screw granulator) or air (in a fluidized bed granulator).

(36) According to some embodiments, the agitation resulting in the system along with the wetting of the components within the formulation results in the aggregation of the primary powder particles to produce wet granules of the fertilizer.

(37) According to some embodiments, water mixed into the fertilizer powder may form bonds between the fertilizer particles that are strong enough to lock them together. However, once the water dries, the powder may fall apart. Therefore, water may not be strong enough to create and hold a bond and the binders of the present invention allow for the creation of a strong bond and resulting in a stable fertilizer granule.

(38) According to some demonstrative embodiments, the granulation may take place using any suitable granulator or granulation method including, for example, Fluidized bed Granulation, Tumbling Granulation, Disc Granulation, Drum Granulation, Mixer-Granulation, Melt Granulation, Double shaft paddle Mixer-Granulation and the like.

(39) According to some embodiments, the fertilizer dust is a potash dust, for example, potash dust which is a byproduct of the process of manufacturing potash.

(40) According to these embodiments, the use of Potash dust may significantly increase the yield of potash production as usually it is cumbersome and difficult to make use of such dust.

(41) According to these embodiments, combining the potash dust with a geopolymer provides a surprising effect of enhanced adherence, and accordingly enables for the granulation of the potash dust.

(42) According to some demonstrative embodiments, the fertilizer composition of the present invention may also include one or more additional binders, e.g., in addition to the geopolymers. According to some embodiments, the one or more additional binders may include any suitable material or compound that may mechanically and/or chemically hold or draw other materials together to form a cohesive whole including, for example, organic or inorganic binders, such as, starch, bentonite, sodium silicate, lignosulfonates, molasses, hydrated lime, bitumen, Portland cement, clay, acids (nitric, hydrochloric, phosphoric, sulphuric), cellulose gum, sucrose, water, water glass, cements, or combinations thereof.

EXAMPLES

Example 1

(43) Fill the Mixer with 2 Kg potash at temperature of 80° C.

(44) 2—Add 500 ppm of Ferric oxide.

(45) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Algenite (product of ICL)+Ca(OH)2+ZnO)

(46) 4—Add 4% W/W Alganite/potash in a vessel

(47) 5—Add 1% W/W Ca(OH)2/Potash

(48) 6—Add 1.2% W/W ZnO/(potash+binder)

(49) 7—Mix homogenously the solids

(50) Note: The calculation of Alganite and Ca(OH)2 weight is relative to potash mass, whereas the mass of ZnO is added relative to overall mass including the binder in order to have Zn element of 1% at final product (for example: 2 Kg of potash, Alganite-80 g, Ca(OH)2-20 g and ZnO 25.2 g)

(51) 8—Add the mix to the potash and mix 1 minute at 4000 rpm.

(52) 9—Add 14-15% (from potash weight!) of hot water (80 degrees) to the mix and mix homogenously at 4000 rpm 5 minutes

(53) 10—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(54) 11—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(55) 12—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(56) Results: single strength 2 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 0.5 kg/gran

Example 2

(57) Fill the Mixer with 2 Kg potash at temperature of 80° C.

(58) 2—Add 500 ppm of Ferric oxide.

(59) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Ca(OH).SUB.2

(60) 5—Add 4% W/W(potash) of Ca(OH).sub.2

(61) 6—Add 1.2% W/W ZnO/(potash+binder)

(62) 7—Mix homogenously the solids

(63) Note: The calculation of Ca(OH).sub.2 weight is relative to potash mass, whereas the mass of ZnO is added relative to overall mass including the binder in order to have Zn element of 1% at final product.

(64) 8—Add the mix to the potash and mix 1 minute at 4000 rpm.

(65) 9—Add 14-15% (from potash weight!) of hot water (80 degrees) to the mix and mix homogenously at 4000 rpm 5 minutes

(66) 10—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(67) 11—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(68) 12—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(69) Results: single strength 2 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 0.3 kg/gran

Example 3—Fill the Mixer with 2 Kg potash at temperature of 80° C.

(70) 2—Add 500 ppm of Ferric oxide.

(71) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Ca(OH).SUB.2.+KSiO.SUB.3.+NaSiO.SUB.3

(72) 4—Add 2.2% W/W Ca(OH).sub.2/potash

(73) 5—Add 1.5% W/W KSiO.sub.3 40%/potash

(74) 6—Add 0.5% W/W NaSiO.sub.3 40%/potash

(75) 7—Add 1.2% W/W ZnO/(potash+binder)

(76) 8—Mix homogenously the solids

(77) Note: The calculation of Ca(OH).sub.2 and the silicates weight is relative to potash mass, whereas the mass of ZnO is added relative to overall mass including the binder in order to have Zn element of 1% at final product.

(78) 9—Add the mix to the potash and mix 1 minute at 4000 rpm.

(79) 10—Add the additional water to get 14-15% in total (from potash weight!) of hot water (80 degrees) to the mix and mix homogenously at 4000 rpm 5 minutes

(80) 11—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(81) 12—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(82) 13—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(83) Results: single strength 2 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 0.8 kg/gran

Example 4

(84) Fill the Mixer with 2 Kg potash at temperature of 80° C.

(85) 2—Add 500 ppm of Ferric oxide.

(86) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Starch+NaSiO3

(87) 4—Add 2.15% W/W Starch/(potash) to the potash and mix 1 minute at 4000 rpm

(88) 5—Add 0.5% W/W diluted NaSiO3/potash the water glass will be diluted according with the total water necessary to get 14-15% moisture.

(89) 6—Mix homogenously the mass at 4000 rpm.

(90) 7—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(91) 11—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(92) 12—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(93) Results: single strength 3 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 0.2 kg/gran

Example 5

(94) Fill the Mixer with 2 Kg potash at temperature of 25° C.

(95) 2—Add 500 ppm of Ferric oxide.

(96) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Bentonite+NaSiO3+CaSO4

(97) 4—Add 0.5% W/W Bentonite/(potash) to the potash and mix 1 minute at 4000 rpm

(98) 5—Add 0.5% W/W CaSO4/(potash) to the potash and mix 1 minute at 4000 rpm

(99) 6—Add 2% W/W NaSiO3 40%/potash

(100) 7—Add additional water water to get 14-15% moisture.

(101) 8—Mix homogenously the mass at 4000 rpm.

(102) 9—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(103) 10—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(104) 11—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(105) Results: single strength 2.5 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 0.1 kg/granule

Example 6

(106) Fill the Mixer with 2 Kg potash at temperature of 70° C.

(107) 2—Add 500 ppm of Ferric oxide.

(108) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Algenite

(109) 4—Add 8% W/W Algenite/potash to the potash and mix 1 minute at 4000 rpm

(110) 5—Add additional water water to get 14-15% moisture.

(111) 6—Mix homogenously the mass at 4000 rpm.

(112) 7—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(113) 8—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(114) 9—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(115) Results: single strength 4.3 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 2.9 kg/granule

Example 7

(116) Fill the Mixer with 2 Kg potash at temperature of 25° C.

(117) 2—Add 500 ppm of Ferric oxide.

(118) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Algenite+Ca(OH).SUB.2

(119) 4—Add 4% W/W Algenite/(potash) to the potash and mix 1 minute at 4000 rpm

(120) 5—Add 4% W/W Ca(OH)2/(potash) to the potash and mix 1 minute at 4000 rpm

(121) 6—Add additional water water to get 14-15% moisture.

(122) 7—Mix homogenously the mass at 4000 rpm.

(123) 8—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(124) 9—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(125) 10—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(126) Results: single strength 2.7 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 1.4 kg/granule

Example 8

(127) Fill the Mixer with 2 Kg potash at temperature of 70° C.

(128) 2—Add 500 ppm of Ferric oxide.

(129) 3—Mix the material during 2 minutes 4000 rpm to destroy the agglomerates and have homogenous feed material.

Binder: Algenite

(130) 4—Add 6% W/W Algenite/potash to the potash and mix 1 minute at 4000 rpm

(131) 5—Add additional water water to get 14-15% moisture.

(132) 6—Mix homogenously the mass at 4000 rpm.

(133) 7—Reduce the velocity to 500 rpm and continue mixing during 1 minutes approximately. (check the during the granulation the granules formation and add small quantities of water if necessary, 0-40 gr).

(134) 8—Empty the mixer and dry the material in fluid bed dryer at 150 degrees 20 minutes or an oven 150 degrees 180 min, mix it manually

(135) 9—Screen the material 2-4 mm (PSD of 1.4 mm-2 mm at maximum 5% and 4 mm-4.75 mm at maximum 5%).

(136) Results: single strength 2.6 kg/gran. Single strength after humidity chamber 24 hours, 79% RH 1.6 kg/granule

(137) While this invention has been described in terms of some specific examples, many modifications and variations are possible. It is therefore understood that within the scope of the appended claims, the invention may be realized otherwise than as specifically described.