Disclosed is a method for the integrated production of two different urea products. One is an aqueous urea solution suitable for use in NOx abatement (generally indicated as Diesel Exhaust Fluid—DEF). The other is a solution used as a fertilizer, viz. Urea Ammonium Nitrate (UAN). The production of DEF and UAN are integrated as follows: ammonia recovered from the production of urea is used as a feed to the production of ammonium nitrate. At least part of an aqueous urea stream from urea prodution, is mixed with ammonium nitrate so as to obtain UAN.

Disclosed is a method for the integrated production of two different urea products. One is an aqueous urea solution suitable for use in NOx abatement (generally indicated as Diesel Exhaust Fluid—DEF). The other is a solution used as a fertilizer, viz. Urea Ammonium Nitrate (UAN). The production of DEF and UAN are integrated as follows: ammonia recovered from the production of urea is used as a feed to the production of ammonium nitrate. At least part of an aqueous urea stream from urea prodution, is mixed with ammonium nitrate so as to obtain UAN.

Disclosed is a method for the integrated production of two different urea products. One is an aqueous urea solution suitable for use in NOx abatement (generally indicated as Diesel Exhaust Fluid—DEF). The other is a solution used as a fertilizer, viz. Urea Ammonium Nitrate (UAN). The production of DEF and UAN are integrated as follows: ammonia recovered from the production of urea is used as a feed to the production of ammonium nitrate. At least part of an aqueous urea stream from urea prodution, is mixed with ammonium nitrate so as to obtain UAN.

Compositions and methods are presented that selectively dissolve calcium from a variety of cementitious materials without dissolving or otherwise degrading calcium silica hydrate (CSH). Preferably, contemplated compositions comprise guanidine bisulfate hydrochloride, which can be prepared from a reaction of urea, hydrochloric acid, and sulfamic acid. Therefore, it is especially contemplated that the compositions contemplated herein are particularly suitable to clean or otherwise condition surfaces of cured concrete, Portland cement-based material, or an aggregate containing CSH.

Compositions and methods are presented that selectively dissolve calcium from a variety of cementitious materials without dissolving or otherwise degrading calcium silica hydrate (CSH). Preferably, contemplated compositions comprise guanidine bisulfate hydrochloride, which can be prepared from a reaction of urea, hydrochloric acid, and sulfamic acid. Therefore, it is especially contemplated that the compositions contemplated herein are particularly suitable to clean or otherwise condition surfaces of cured concrete, Portland cement-based material, or an aggregate containing CSH.

Disclosed is a method for the removal of urea dust from the off-gas of a finishing section of a urea production plant. the method comprises subjecting the off-gas to quenching with water so as to produce quenched off-gas. The quenched off-gas is subjected to humidification by mixing said quenched gas stream with a humidification fluid selected from (a) saturated steam and (b) superheated steam mixed with a second aqueous stream, so as to produce a humidified gas stream, subjecting said humidified gas stream to particle separation (i.e., dust removal) by means of a scrubbing liquid in which at least part of the particles in the gas stream are soluble.

Disclosed is a method for the removal of urea dust from the off-gas of a finishing section of a urea production plant. the method comprises subjecting the off-gas to quenching with water so as to produce quenched off-gas. The quenched off-gas is subjected to humidification by mixing said quenched gas stream with a humidification fluid selected from (a) saturated steam and (b) superheated steam mixed with a second aqueous stream, so as to produce a humidified gas stream, subjecting said humidified gas stream to particle separation (i.e., dust removal) by means of a scrubbing liquid in which at least part of the particles in the gas stream are soluble.

The present invention relates to a method for the production of an urea ammonium sulphate (UAS) composition, wherein said UAS composition comprises 1 to 40 weight % of ammonium sulphate (AS) relative to the total weight of the UAS composition, from sulphuric acid, ammonia and/or ammonium carbamate, and urea, in a pipe reactor comprising at least a reactor section wherein feeds of sulphuric acid and/or ammonium bisulphate, ammonia and/or ammonium carbamate, and urea are combined to obtain said urea ammonium sulphate (UAS) composition, comprising the step of including a viscosity-reducing agent, selected from the group of water soluble aluminium salts, into one or more of said feeds. Preferably, said agent is an aluminium sulphate (AluS). The present invention also relates to a pipe reactor for the production of a urea ammonium sulphate (UAS) composition from sulphuric acid, ammonia and/or ammonium carbamate, and urea, the pipe reactor comprising at least a reactor section wherein continuous feeds of sulphuric acid and/or ammonium bisulphate, ammonia and/or ammonium carbamate and urea are combined to obtain said urea ammonium sulphate (UAS) composition, wherein the pipe reactor further comprises means for supplying an aqueous solution of a viscosity-reducing agent to the urea solution upstream of said pipe reactor section, which agent reduces the viscosity of said UAS solution or slurry. The present invention also relates to the use of aluminium sulphate as viscosity-reducing agent in in a method for the production of urea ammonium sulphate (UAS) composition, wherein said UAS composition comprises 1 to 40 weight % of ammonium sulphate (AS) relative to the total weight of the UAS composition, from sulphuric acid, ammonia and/or ammonium carbamate, and urea, in a pipe reactor comprising at least a reactor section wherein continuous feeds of sulphuric acid and/or ammonium bisulphate, ammonia and/or ammonium carbamate and urea are combined to obtain said urea ammonium sulphate (UAS) composition.

The present invention relates to a method for the production of an urea ammonium sulphate (UAS) composition, wherein said UAS composition comprises 1 to 40 weight % of ammonium sulphate (AS) relative to the total weight of the UAS composition, from sulphuric acid, ammonia and/or ammonium carbamate, and urea, in a pipe reactor comprising at least a reactor section wherein feeds of sulphuric acid and/or ammonium bisulphate, ammonia and/or ammonium carbamate, and urea are combined to obtain said urea ammonium sulphate (UAS) composition, comprising the step of including a viscosity-reducing agent, selected from the group of water soluble aluminium salts, into one or more of said feeds. Preferably, said agent is an aluminium sulphate (AluS). The present invention also relates to a pipe reactor for the production of a urea ammonium sulphate (UAS) composition from sulphuric acid, ammonia and/or ammonium carbamate, and urea, the pipe reactor comprising at least a reactor section wherein continuous feeds of sulphuric acid and/or ammonium bisulphate, ammonia and/or ammonium carbamate and urea are combined to obtain said urea ammonium sulphate (UAS) composition, wherein the pipe reactor further comprises means for supplying an aqueous solution of a viscosity-reducing agent to the urea solution upstream of said pipe reactor section, which agent reduces the viscosity of said UAS solution or slurry. The present invention also relates to the use of aluminium sulphate as viscosity-reducing agent in in a method for the production of urea ammonium sulphate (UAS) composition, wherein said UAS composition comprises 1 to 40 weight % of ammonium sulphate (AS) relative to the total weight of the UAS composition, from sulphuric acid, ammonia and/or ammonium carbamate, and urea, in a pipe reactor comprising at least a reactor section wherein continuous feeds of sulphuric acid and/or ammonium bisulphate, ammonia and/or ammonium carbamate and urea are combined to obtain said urea ammonium sulphate (UAS) composition.

A fluidized bed granulator for granulation with urea or urea-containing liquids is described, wherein the granulation liquid is supplied via a supply manifold comprising a header and risers. The risers are at least in part provided inside channels for secondary gas.