公开(公告)号：US10828593B2

公开(公告)日：2020-11-10

申请号：US16236097

申请日：2018-12-28

Applicant: Stamicarbon B.V.

Inventor： Petrus Catharina Gerlach Soons ,  Wilfried Marc Renaat Dirkx

IPC: B01D47/06 ,  B01D47/10 ,  C07C273/02

Abstract: 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, and subjecting the quenched off-gas to scrubbing using at least one venturi scrubber. As a result, a lower pressure drop over the scrubber is attained, and a more efficient growth of urea particles, facilitating the removal thereof.

公开(公告)号：US10207216B2

公开(公告)日：2019-02-19

申请号：US14902831

申请日：2014-07-04

Applicant: Stamicarbon B.V.

Inventor： Petrus Catharina Gerlach Soons ,  Wilfried Marc Renaat Dirkx

IPC: B01D47/10 ,  B01D47/06 ,  C07C273/02

Abstract: Disclosed is a method for the removal of urea dust from the off-gas of a finishing section (1) of a urea production plant, the method comprises subjecting the off-gas to quenching with water (06) so as to produce quenched off-gas, and subjecting the quenched off-gas to scrubbing using at least one venturi scrubber (11). As a result, a lower pressure drop over the scrubber is attained, and a more efficient growth of urea particles, facilitating the removal thereof.

公开(公告)号：US10227265B2

公开(公告)日：2019-03-12

申请号：US15742488

申请日：2016-07-06

Applicant: STAMICARBON B.V.

Inventor： Petrus Catharina Gerlach Soons ,  Stefan H. Schaafsma

IPC: C05C9/00 ,  C05C3/00 ,  C05G3/00 ,  B01J2/16

Abstract: Disclosed is a method of making a granulate of a urea product comprising urea and a salt, such as urea ammonium sulfate, having a high content of the salt. The high content is such as to provide an amount of the salt above the limit of solubility of the salt in urea. The granulate of the invention is characterized by having a smooth surface, which, e.g. in the event of urea ammonium sulfate, is not normally the case for granulate having the aforementioned high ammonium sulfate content. According to the invention this is realized by dividing the feed liquids to granulation. This division is based on non-final granulation liquids of a sufficiently high content of the salt, and a final granulation liquid (determining the surface) having a salt content of below the solubility limit of the salt, or no salt at all. E.g. in the event of urea ammonium sulfate, the non-final granulation liquids possibly are a slurry of urea and more than 20 wt. % of ammonium sulfate. The final granulation liquid then has 0-20 wt. % of ammonium sulfate, i.e. below the solubility limit.