公开(公告)号：US10882820B2

公开(公告)日：2021-01-05

申请号：US16537315

申请日：2019-08-09

Applicant: Stamicarbon B.V.

Inventor： Eelco Mostert

IPC: C07C273/04 ,  B01J19/24 ,  C07C273/16 ,  B01B1/00

Abstract: Disclosed is a novel method of controlling the formation of biuret in urea production. This is accomplished by reducing or preventing the formation of biuret in a concentration section, particularly in one or more concentrators or evaporators. The method comprises controlling the residence time of a urea aqueous stream treated in such concentration section in a manner independently of the volume flow per time interval of said stream into said concentration section. The residence time can be controlled, e.g., by providing the concentration section with an adjustable volume or by adding a gas to the urea stream to be treated. A combination of such measures can also be applied.

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：US20200306663A1

公开(公告)日：2020-10-01

申请号：US16469129

申请日：2018-10-26

Applicant: Stamicarbon B.V.

Inventor： Dorin POPPA

IPC: B01D5/00 ,  C07C273/14 ,  C07C273/04 ,  F28D7/06 ,  F28F9/02

Abstract: Described are a high pressure carbamate condenser, urea plant, and urea production process. The high pressure carbamate condenser as described is of the shell-and-tube heat exchanger type with a tube bundle and has a redistribution chamber connected to tubes of the tube bundle and to a duct. The duct extends between the redistribution chamber and the shell.

公开(公告)号：US10759745B2

公开(公告)日：2020-09-01

申请号：US16186410

申请日：2018-11-09

Applicant: Stamicarbon B.V.

Inventor： Ronny Albert Mathijs Pustjens ,  Johan Albert Arno Van Den Tillaart

IPC: C07C273/04 ,  B01D5/00 ,  C07C273/16 ,  B01J19/00 ,  C07C273/14

Abstract: Processes and plants for the production of purified urea solution are described. In a described urea production process, urea is produced in a synthesis section without a high pressure stripper and the urea solution is subjected to purification after the recovery section, to give purified urea solution and off-gas. The purification comprises e.g. steam stripping.

公开(公告)号：US10730002B2

公开(公告)日：2020-08-04

申请号：US15495667

申请日：2017-04-24

Applicant: Stamicarbon B.V.

Inventor： Brian Sayre Higgins ,  John Marshall Tate, III ,  Robert Arthur Yates ,  Marcel Julien Pomerleau ,  Jon Michael Heon ,  Wilfried Marc Renaat Dirkx ,  Juan Coloma González

IPC: B01D47/05 ,  B01D47/06 ,  B01D47/10 ,  B01D47/12 ,  B01D53/40 ,  B01D53/58 ,  B01D53/79 ,  C07C273/16 ,  B01J2/04 ,  C05C9/00

Abstract: Disclosed are methods and systems for removing submicron particles from a gas stream, in particular from urea prilling off-gas, wherein a Venturi ejector is used. A method comprises contacting a gas stream containing submicron particles in a Venturi ejector with an injected high velocity scrubbing liquid to provide a pumping action, wherein the scrubbing liquid has an initial velocity of at least 25 m/s and wherein the ratio of scrubbing liquid and gas flow is between 0.0005 and 0.0015 (m3/h)/(m3/h).

公开(公告)号：US10526281B2

公开(公告)日：2020-01-07

申请号：US16098837

申请日：2017-04-28

Applicant: STAMICARBON B.V.

Inventor： Eelco Mostert

IPC: C07C273/04 ,  C07C273/16 ,  C07C275/02 ,  C07C275/62 ,  B01D53/58 ,  B01J4/00

Abstract: Disclosed is a novel method of controlling the formation of biuret in urea production, and particularly reducing, preventing or reversing such formation. This is accomplished by adding liquid ammonia to a urea aqueous stream. This addition is done at one or more positions downstream of a recovery section in a urea plant. The addition of liquid ammonia serves to shift the equilibrium of biuret formation from urea, to the side of the formation of urea from biuret and ammonia. The invention can be accomplished also in pre-existing urea plant, by the simple measure of providing an appropriate inlet for liquid ammonia, in fluid communication with a source of such liquid ammonia.

公开(公告)号：US10457609B2

公开(公告)日：2019-10-29

申请号：US15573448

申请日：2016-12-21

Applicant: Stamicarbon B.V.

Inventor： Giusy Elisa Puci ,  Joey Dobree

IPC: C05C9/00 ,  C05C1/00 ,  C01C1/18 ,  C07C273/04 ,  B01J12/00 ,  B01J14/00 ,  B01D53/58 ,  B01D53/14 ,  B01D53/78 ,  B01J19/24

Abstract: The invention relates to a process for the production of urea ammonium nitrate, a system and a method of modifying a plant. The process comprises treating ammonia-containing off-gas resulting from the production of ammonium nitrate (AN off-gas) with acidic scrubbing liquid in a finishing treatment section having a gas inlet in fluid communication with a gas outlet of a finishing section of a urea production unit, wherein the finishing section is adapted to solidify urea liquid, and wherein said finishing treatment section is adapted to subject ammonia-containing off-gas of the finishing section to treatment with an acidic scrubbing liquid.

公开(公告)号：US10384184B2

公开(公告)日：2019-08-20

申请号：US15669818

申请日：2017-08-04

Applicant: Stamicarbon B.V.

Inventor： Luc Louis Maria Dieltjens

IPC: B01J12/00 ,  C07C273/04

Abstract: The invention relates to a urea plant with a CO2 and a NH3 feed, which comprises a purge line, characterized in that the purge line is connected with a fuel gas input line of a utility plant or an NH3 plant.

公开(公告)号：US10358413B2

公开(公告)日：2019-07-23

申请号：US15568795

申请日：2016-04-25

Applicant: Stamicarbon B.V.

Inventor： Johannes Henricus Mennen

IPC: C07D251/60 ,  C07D251/62 ,  C07C273/12 ,  B01J19/24

Abstract: Disclosed is an integrated process for the production of urea and melamine, as well as a system for carrying out the process. The invention thereby pertains to an integrated process of the type wherein off-gas obtained from the production of melamine is entered into the process for the production of melamine, by condensation in the presence of water. A typical embodiment thereof is the condensation in the presence of an aqueous carbamate solution obtained from urea recovery. In accordance with the invention, said condensation takes place at a substantially lower pressure than the pressure at which the melamine off-gas is obtained. To this end, the pressure of the off-gas is reduced typically by 2-10 bar. In connection herewith, the system of the invention comprises a pressure reducing unit downstream of an outlet for the melamine off-gas, and upstream of a section for the condensation of the off-gas. The invention also includes a method for the modernization of an integrated system for the production of melamine and urea. This is accomplished by adding the aforementioned pressure reducing unit to a pre-existing system.

公开(公告)号：US10315925B2

公开(公告)日：2019-06-11

申请号：US15528708

申请日：2015-11-26

Applicant: Stamicarbon B.V.

Inventor： Johannes Henricus Mennen ,  Fredericus Henricus Maria Buitink ,  Willem Frederik Roos

IPC: C01C1/18 ,  C05C1/00 ,  C05C9/00 ,  B01J19/00 ,  B01J10/00

Abstract: The invention provides a method and a plant for producing urea ammonium nitrate (UAN). The method involves the use of a condensation section, optionally in combination with a medium pressure decomposition section, between the dissociation and neutralization sections. The invention further provides a method of modifying an existing UAN plant. The advantages of the process of the invention are that the emission of CO2 can be reduced, the plant capacity can be increased and the high capital expenditure needed for CO2 compression equipment is reduced.