摘要:
A process for producing a coated particle to provide controlled release characteristics. In this process the mixing of the substrate and coating is made in a mixing device and that mixture is then transferred to a reactor vessel different from the mixing device where the chemical curing of the coating over the particles takes place. Several layers of coating can be applied by repeating the steps and it can be run in a fully continuous manner.
摘要:
A fertilizer supplying animal nutrients including a core particle having an outer surface and comprising compounds containing animal nutrients, and a coating of urea on the outer surface of the core particle, and further a process of making the fertilizer including the steps of: screening animal nutrient core particles comprising a powdered substance containing an animal nutrient, to a preselected particle size; spraying melted urea onto the surface of the nutrient core particles to produce a coating on the nutrient core particles; granulating the nutrient core particles with sprayed melted urea to produce nutrient core granules; and cooling the nutrient core granules.
摘要:
A controlled release agricultural absorbent based product including particles of an absorbent material containing capillaries/voids between 10-200 microns in cross-sectional diameter which is impregnated in an amount of 40-95% of the capillaries/voids volume with an agriculturally beneficial material selected from the group consisting of fertilizers, insecticides, herbicides and fungicides, being produced by a process including steps of 1) introducing water to particles of absorbent material to result in absorption of water within the absorbent material, 2) heating the absorbent particles and water to transform the water within the absorbent particles to steam, 3) introducing the heated absorbent particles to an agriculturally beneficial material in aqueous solution to essentially saturate the absorbent particles with the agriculturally beneficial material, 4) granulating the combination of agriculturally beneficial material and saturated absorbent particles to solidify and harden the mixture, resulting in the agglomeration of absorbent particles into granules, and 5) drying the granules.
摘要:
A prilling apparatus and process for producing seed material for size enlargement processes such as a granulation process for bisphenol. The apparatus includes a fluidized bed system with a spray header therein for producing spray droplets of material in a gaseous stream such as nitrogen to form prills of less than about 1 mm diameter.
摘要:
The granulation of molten material using a heat transfer process whereby solid particles are heated, dried, or cooled by a gas: Particles are repeatedly lifted and dropped as, for example, in flighted rotary drums. By forced recirculation, gas is passed through showering particles generally perpendicular to their plane of fall. Examples show gas forced to contact particles in this manner imparts an overall volumetric heat transfer coefficient to a rotary drum superior to that expected from classical literature or presently operating rotary drum heat exchangers. Disclosure teaches gas temperature adjustment between forced recirculations. Technique usage will reduce exchanger capital cost, increase energy efficiency, and reduce pollution problems. Also, prewetting of the particles in certain instances can be utilized to effect substantially increased pseudo volumetric heat transfer coefficients when cooling non-hygroscopic materials.
摘要:
an improved process for the granulation or coating of hygroscopic or nonhygroscopic materials where melt is sprayed onto cascading granules of common or uncommon substrate in an enclosed vessel such as a rotary drum preferably with lifting flights which provide maximum mixing of the granules and the atmosphere enclosed in the unit and where heat given off by solidification of the melt is absorbed by evaporation of water which is atomized as an extremely fine mist into areas of the vessel which are not subtended by falling granules. Evaporation is effected without impingement of the mist on the granules or vessel internals. Air for evaporation is pulled through the vessel concurrent with the flow of granules and its moisture content is regulated below the critical humidity of the granules throughout the vessel. Some recycle of undersize granules discharged from the vessel is maintained for size control; however, examples show the recycle rate decreased by 87 percent over recycle cooled processes as 73 percent of the heat evolved is removed by evaporation of water mist. An equation is developed which mathematically represents the thermodynamics of the process and specific values are presented for variables when granulating sulfur or urea.
摘要:
The invention relates to methods and systems for coating substrates. In particular, the invention relates to methods and systems in which the coating and curing steps are performed in separate vessels. These methods and systems provide a more effectively controlled and efficient coating process.
摘要:
A controlled release agricultural absorbent based product including particles of an absorbent material containing capillaries/voids between 10-200 microns in cross-sectional diameter which is impregnated in an amount of 40-95% of the capillaries/voids volume with an agriculturally beneficial material, at least including ureaform, and said beneficial material being selected from the group consisting of fertilizers, insecticides, herbicides and fungicides, being produced by a process including steps of 1) introducing water to particles of absorbent material to result in absorption of water within the absorbent material, 2) heating the absorbent particles and water to transform the water within the absorbent particles to steam, 3) introducing the absorbent particles to an agriculturally beneficial material, at least including ureaform, to saturate the beneficial material, 4) granulating the beneficial material and saturated absorbent particles to solidify and harden the mixture, resulting in the agglomeration of absorbent particles into granules, and drying the granules.
摘要:
A controlled release agricultural absorbent based product including particles of an absorbent material containing capillaries/voids between 10-200 microns in cross-sectional diameter which is impregnated in an amount of 40-95% of the capillaries/voids volume with an agriculturally beneficial material selected from the group consisting of fertilizers, insecticides, herbicides and fungicides, being produced by a process including steps of 1) introducing water to particles of absorbent material to result in absorption of water within the absorbent material, 2) heating the absorbent particles and water to transform the water within the absorbent particles to steam, 3) introducing the heated absorbent particles to an agriculturally beneficial material in aqueous solution to essentially saturate the absorbent particles with the agriculturally beneficial material, 4) granulating the combination of agriculturally beneficial material and saturated absorbent particles to solidify and harden the mixture, resulting in the agglomeration of absorbent particles into granules, and 5) drying the granules.
摘要:
Uniform, free-flowing, non-friable P.sub.2 S.sub.5 granules having a predetermined reactivity can be produced by accretion by spraying molten P.sub.2 S.sub.5 Sonto cascading, smaller solid particles of P.sub.2 S.sub.5. The process can be used to produce any reactivity grade of P.sub.2 S.sub.5 by adjusting processing conditions. The process can also be used to produce P.sub.2 S.sub.5 in a form suitable for bulk shipping.