Abstract: Disclosed is a particulate, urea-containing composition, to a method and apparatus for producing it, to the use thereof as fertilizer, as technical urea or as feed additive, and to the use of an additive for producing a particulate, urea-containing composition.

Abstract: A urea granulation process with a scrubbing system may involve at least one gaseous waste stream for removal of dust and ammonia whereby the waste stream may be processed through a combination of process steps. In some examples, the process steps may involve washing the dust and ammonia laden stream with water and/or an aqueous urea solution whereby a dust-laden liquid stream and a dust-reduced stream is generated. The process steps may further involve reacting the dust-reduced stream with formaldehyde to form a stream comprising hexamethylenetetramine and urea-formaldehyde and clean off-gas. In some cases, the gas stream may be directed first through the washing step and then through the reacting step.

Abstract: A urea granulation process with a scrubbing system may involve at least one gaseous waste stream for removal of dust and ammonia whereby the waste stream may be processed through a combination of process steps. In some examples, the process steps may involve washing the dust and ammonia laden stream with water and/or an aqueous urea solution whereby a dust-laden liquid stream and a dust-reduced stream is generated. The process steps may further involve reacting the dust-reduced stream with formaldehyde to form a stream comprising hexamethylenetetramine and urea-formaldehyde and clean off-gas. In some cases, the gas stream may be directed first through the washing step and then through the reacting step.

Abstract: Disclosed is a method for producing granular urea and reducing ammonia emissions in a gaseous waste stream of the urea granulation process. The method includes the steps of granulating urea and generating a gaseous waste stream from the granulation of the urea, first washing the waste stream in a first scrubber dust stage to remove dust form the gaseous waste stream, and then reacting the gaseous waste stream with formaldehyde in a formaldehyde stage to generate a hexamethylenetetramine and urea-formaldehyde liquid stream, and an ammonia-reduced off-gas stream.

Abstract: A reactor for producing nitrogen-containing fertilizer granules comprising a reactor vessel having inside walls coated with a layer of at least one organic silica compound.

Abstract: Disclosed is a method for producing granular urea and reducing ammonia emissions in a gaseous waste stream of the urea granulation process. The method includes the steps of granulating urea and generating a gaseous waste stream from the granulation of the urea, first washing the waste stream in a first scrubber dust stage to remove dust form the gaseous waste stream, and then reacting the gaseous waste stream with formaldehyde in a formaldehyde stage to generate a hexamethylenetetramine and urea-formaldehyde liquid stream, and an ammonia-reduced off-gas stream.

Abstract: A method for producing urea granules having low moisture absorption capacity, with a urea granulator, having a granule flow inlet side and oppositely a granule flow outlet side, forming an axis alongside which granules from a urea solution and a urea/ammonium salt-stream are formed, whereby the solution and the salt-stream are sprayed as a mixture or separately via a feed system unit via various nozzles into the granulator onto a seed material. In this process the highest amount of the salt-stream is sprayed into the granulator at the granule flow inlet side and the amount of the salt-stream is decreased alongside the axis of the granulator from the granule flow inlet side to the granule flow outlet side.

Abstract: The invention relates to a method for reducing aerosol emissions from a urea granulation plant with a recovery of the resulting scrubber bleeds, with a granulator producing urea from a concentrated urea solution and an evaporation of the included water, giving urea granulates and an exhaust of dust, ammonia and ammonium cyanate, and a following scrubbing or removing stage for the dust, and a following scrubbing acid stage, resulting in a first stream comprising mainly aerosols and a second stream comprising ammonium salts, and a following aerosol stage with spray and collection devices, releasing a first stream of an exhaust of air, and a second stream of ammonium cyanate and water, and the second stream of the aerosol stage of ammonium cyanate and water is recovered into the urea granulation plant or into a urea fertilizer plant.

Abstract: A method for producing urea granules having low moisture absorption capacity, with a urea granulator, having a granule flow inlet side and oppositely a granule flow outlet side, forming an axis alongside which granules from a urea solution and a urea/ammonium salt-stream are formed, whereby the solution and the salt-stream are sprayed as a mixture or separately via a feed system unit via various nozzles into the granulator onto a seed material. In this process the highest amount of the salt-stream is sprayed into the granulator at the granule flow inlet side and the amount of the salt-stream is decreased alongside the axis of the granulator from the granule flow inlet side to the granule flow outlet side.

Abstract: A urea granulation process and the apparatus suitable for operating that process integrates a method for reducing ammonia emissions from a urea granulation plant which is emitted by a urea production process by scrubbing the off-gas and recovering the scrubber bleed and integrating it into the granulation process so that ammonium salts are completely contained by the process.

Abstract: The invention relates to a process for the granulation of a concentrated urea solution whereas the granulation produces a urea granulate and a dust laden air, which is then fed into a dust scrubber which removes the coarser dust with a less concentrated urea solution and which releases a residual air comprising air with ammonia, carbon dioxide water and an aerosol comprising mainly ammonium isocyanate and a part of very fine urea sublimate, whereas the aerosol is then separated off and fed into a isomerisation unit which comprises a stripping where the ammonium isocyanate reacts with steam to form urea which is then redirected into the dust scrubber as a less concentrated urea solution, and the residual air is directed into an acidic scrubber which releases clean air into the atmosphere which finally leads to a recycling of the aerosol of ammonium isocyanate into urea. The invention also relates to a device for carrying out the related process.