公开(公告)号：US20240270684A1

公开(公告)日：2024-08-15

申请号：US18553330

申请日：2023-07-06

申请人： Stamicarbon B.V.

发明人： Ahmed ABDELMAGID ,  Wilhelmus Hubertus GEURTS

IPC分类号： C07C273/12 ,  C07C273/04 ,  C07C273/16 ,  C07D251/60 ,  C07D251/62

CPC分类号： C07C273/12 ,  C07C273/04 ,  C07C273/16 ,  C07D251/60 ,  C07D251/62

摘要： The disclosure pertains to a process for the production of urea and melamine, wherein off-has from a high pressure melamine plant is combined with a urea liquid obtained from flashing of a urea synthesis solution. Also disclosed is a system for the combined production, and the modification of an existing plant or system.

公开(公告)号：US20240059623A1

公开(公告)日：2024-02-22

申请号：US18256554

申请日：2023-02-14

申请人： STAMICARBON B.V.

发明人： Johan Albert Arno VAN DEN TILLAART ,  Eelco MOSTERT

IPC分类号： C05C9/00 ,  C05G5/23 ,  C07C273/04 ,  C07C273/16

CPC分类号： C05C9/00 ,  C05G5/23 ,  C07C273/04 ,  C07C273/16

摘要： A urea plant and urea production process of the stripping type are provided that are adapted for making Diesel Exhaust Fluid (DEF) or precursor thereof in a DEF production unit downstream of a treatment section. The treatment section receives a part of the urea synthesis stream from a reaction zone, in particular bypassing the HP stripper.

公开(公告)号：US20240002335A1

公开(公告)日：2024-01-04

申请号：US18035451

申请日：2021-09-10

申请人： Casale SA

发明人： Leonardo Marrone ,  Andrea Beretti

IPC分类号： C07C273/02 ,  C07C273/04 ,  C07C273/16 ,  B01J2/02

CPC分类号： C07C273/02 ,  C07C273/04 ,  C07C273/16 ,  B01J2/02

摘要： A process of prilling of a urea melt comprising the use of calcium lignosulfonate or carboxymethyl starch as additive to obtain a formaldehyde-free urea product.

公开(公告)号：US20230391716A1

公开(公告)日：2023-12-07

申请号：US18035625

申请日：2022-01-07

申请人： Tsinghua University

发明人： Yue PENG ,  Junhua LI ,  Zhen CHEN ,  Haibo YIN ,  Rong WANG

IPC分类号： C07C273/16 ,  B01D53/78 ,  B01D53/56

CPC分类号： C07C273/16 ,  B01D53/78 ,  B01D53/56 ,  B01D2258/0283

摘要： The present disclosure relates to a method and a system for preparing urea by coupling denitration with electrocatalytic reduction. Specifically, the method of the present disclosure comprises: introducing an absorption solution containing nitrite and nitrate, which is generated by subjecting flue gas containing nitric oxide to a denitration step, into a separation step to separate the nitrite and the nitrate, thereby obtaining a solution rich in the nitrite and the nitrate; and introducing the solution rich in the nitrite and the nitrate generated in the separation step into an electrocatalysis step, and carrying out the electrocatalytic reduction in the presence of carbon dioxide or carbonate ions to generate a urea solution. The system of the present disclosure comprises: a denitration device, a separation device connected to the denitration device, and an electrocatalytic device connected to the separation device. The method and system of the present disclosure can be used for the deep removal of nitrogen oxides from industrial flue gas at a low temperature, and can achieve the recycling of nitrogen.

公开(公告)号：US20230303485A1

公开(公告)日：2023-09-28

申请号：US18035030

申请日：2021-09-10

申请人： Casale SA

发明人： Leonardo Marrone

IPC分类号： C07C273/16 ,  C05C9/00

CPC分类号： C07C273/16 ,  C05C9/005

摘要： A process for the production of feed grade urea starting from a liquid urea melt, the process comprising processing the urea melt (6) to promote the formation of biuret until a concentration of at least 3% biuret, and subjecting the so obtained biuret-containing urea melt (8) to a shaping process to obtain a granular urea product.

公开(公告)号：US11535586B2

公开(公告)日：2022-12-27

申请号：US17287895

申请日：2019-11-07

申请人： Casale SA

发明人： Leonardo Marrone

IPC分类号： C07C273/16 ,  B01J19/24 ,  C07C273/04 ,  B01D1/22 ,  B01D9/00

摘要： A process for synthesis of urea from CO2 and NH3 wherein a steam flow (13) produced in the condenser (3) of a high-pressure synthesis loop is compressed to raise its pressure and temperature before using the steam as a heat source for a downstream step of the process.

公开(公告)号：US20220184545A1

公开(公告)日：2022-06-16

申请号：US17684716

申请日：2022-03-02

申请人： Stamicarbon B.V.

发明人： Brian Sayre HIGGINS

IPC分类号： B01D47/12 ,  B01D47/10 ,  B01D47/06 ,  C07C273/16 ,  B01D47/05 ,  B03C3/013

摘要： Disclosed is a method for the removal of soluble particulate matter from a gas stream, such as urea dust from the off-gas of a finishing section of a urea production plant. The method comprises subjecting the off-gas to at least two quenching stages an aqueous quenching liquid. The quenching liquid used in a first, upstream quench stage, is allowed to have a higher concentration of dissolved particulate matter than the quenching liquid in the second, downstream quench stage. The quenched gas is led through a particle capture zone, typically comprising one or more of a wet scrubber, a Venturi scrubber, and a wet electrostatic precipitator.

公开(公告)号：US20220064109A1

公开(公告)日：2022-03-03

申请号：US17418512

申请日：2020-04-30

申请人： YARA INTERNATIONAL ASA

发明人： Lino Giovanni PORRO

IPC分类号： C07C273/16 ,  C07C269/08 ,  B01J19/24 ,  B01J19/00 ,  B01J8/06

摘要： Shell-and-tube strippers for stripping a urea/carbamate mixture, related systems, methods, and uses. The stripper includes a shell, a plurality of tubes disposed within the shell, and a heating fluid distributor for homogenizing the flow of a heating fluid near a heating fluid inlet. The heating fluid distributor includes an edge wall and a laterally disposed heating fluid distribution plate. Related systems, methods, and uses are also provided.

公开(公告)号：US10894764B2

公开(公告)日：2021-01-19

申请号：US16494710

申请日：2018-03-06

申请人： TOYO ENGINEERING CORPORATION

发明人： Shuhei Nakamura ,  Akiko Sugiura ,  Keigo Sasaki

IPC分类号： C07C273/16 ,  B01J2/00 ,  C07C275/00

摘要： Precipitation of an ammonium salt is prevented while suppressing an increase in water content of the aqueous urea solution which is to be supplied to a urea granulation step, when recovering and using urea and NH3 in a gas which contains urea dust and NH3 and which arises from a urea granulation step.

公开(公告)号：US10766856B2

公开(公告)日：2020-09-08

申请号：US16698734

申请日：2019-11-27

申请人： STAMICARBON B.V.

发明人： Eelco Mostert

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

摘要： 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.