Method for producing solid urea by granulation, wherein the granulation is fed with liquid urea having a purity greater than 98% by weight and not containing formaldehyde.

Method for solidifying a chemical product (10) which is in melt form, comprising the following steps: subjecting a first stream (10a) of said chemical product to a prilling stage, with production of prills (12) of varying diameter; feeding said prills (12) to a screening device, which separates them according to their diameter into at least a first fraction (13) and a second fraction (14), the average diameter of the prills of said first fraction (13) being smaller than the average diameter of the prills of said second fraction (14); subjecting a second stream (10b) of said chemical product and the first fraction (13) of prills to a granulation stage, with the production of granules (16).

Method for solidifying a chemical product (10) which is in melt form, comprising the following steps: subjecting a first stream (10a) of said chemical product to a prilling stage, with production of prills (12) of varying diameter; feeding said prills (12) to a screening device, which separates them according to their diameter into at least a first fraction (13) and a second fraction (14), the average diameter of the prills of said first fraction (13) being smaller than the average diameter of the prills of said second fraction (14); subjecting a second stream (10b) of said chemical product and the first fraction (13) of prills to a granulation stage, with the production of granules (16).

Provided is a device for granulating, agglomerating, pelletising, drying and/or coating, the device including a swirl chamber, a distribution chamber, wherein the swirl chamber is separated from the distribution chamber by a base and wherein a powder to be granulated or a powder mixture to be granulated is presented in the swirl chamber, the device further including at least one agitator for thoroughly mixing the powder to be granulated or the powder mixture to be granulated and at least one addition device for a liquid, wherein the base is designed in several parts and at least one base part is horizontally and/or vertically displaceable, with the result that that the base becomes a distributor plate. Also provided is a method for granulating, agglomerating, pelletising, drying and/or coating using such a device and a base suitable for use as a distributor plate in a convective drying apparatus.

Provided is a device for granulating, agglomerating, pelletising, drying and/or coating, the device including a swirl chamber, a distribution chamber, wherein the swirl chamber is separated from the distribution chamber by a base and wherein a powder to be granulated or a powder mixture to be granulated is presented in the swirl chamber, the device further including at least one agitator for thoroughly mixing the powder to be granulated or the powder mixture to be granulated and at least one addition device for a liquid, wherein the base is designed in several parts and at least one base part is horizontally and/or vertically displaceable, with the result that that the base becomes a distributor plate. Also provided is a method for granulating, agglomerating, pelletising, drying and/or coating using such a device and a base suitable for use as a distributor plate in a convective drying apparatus.

A process of granulation of a urea melt, comprising: adding a first additive containing carboxymethyl starch to one or more first stage(s) of the granulation process, to form a carboxymethyl starch containing inner layer of urea granules, and adding a second additive containing calcium lignosulfonate to one or more second stage(s) of the granulation process, downstream said first stages, to form granules with a coating containing calcium lignosulfonate.

A process of granulation of a urea melt, comprising: adding a first additive containing carboxymethyl starch to one or more first stage(s) of the granulation process, to form a carboxymethyl starch containing inner layer of urea granules, and adding a second additive containing calcium lignosulfonate to one or more second stage(s) of the granulation process, downstream said first stages, to form granules with a coating containing calcium lignosulfonate.

Process for making a powder or granule containing (A) at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and of glutamic acid diacetate (GLDA) and of iminodisuccinic acid (IDS), (B) at least one alkali metal salt of a C.sub.10-C.sub.20 fatty acid,
in a weight ratio of (A):(B) of from 40:1 up to 1,000:1,
wherein said powder or granule contains at least 75% by weight of chelating agent (A),
said process comprising the steps of (c) mixing the at least one chelating agent (A) and the at least one alkali metal salt of fatty acid (B) in the presence of water, (d) removing most of said water by spray-drying or by spray granulation using a gas with an inlet temperature of at least 125° C.

Process for making a powder or granule containing (A) at least one chelating agent selected from alkali metal salts of methyl glycine diacetic acid (MGDA) and of glutamic acid diacetate (GLDA) and of iminodisuccinic acid (IDS), (B) at least one alkali metal salt of a C.sub.10-C.sub.20 fatty acid,
in a weight ratio of (A):(B) of from 40:1 up to 1,000:1,
wherein said powder or granule contains at least 75% by weight of chelating agent (A),
said process comprising the steps of (c) mixing the at least one chelating agent (A) and the at least one alkali metal salt of fatty acid (B) in the presence of water, (d) removing most of said water by spray-drying or by spray granulation using a gas with an inlet temperature of at least 125° C.

The spray dryer comprises a spray drying chamber having a substantially cylindrical top section, a conical wall and a narrowed lower section. In the top section, atomizing means is provided. One or more cameras are associated with the drying chamber in order to monitor the process. At least one of the cameras is an infrared camera adapted for measuring the temperature within a predefined area.