公开(公告)号：US06518457B1

公开(公告)日：2003-02-11

申请号：US10198962

申请日：2002-07-22

Applicant: Eiji Sakata ,  Yasuhiko Kojima

Inventor： Eiji Sakata ,  Yasuhiko Kojima

IPC: C07C27304

CPC classification number: C07C273/04

Abstract: A process for the synthesis of urea, which comprises subjecting a urea synthesis solution from a urea synthesis column to stripping with a raw material carbon dioxide under a pressure approximately equal to the urea synthesis pressure to separate a major portion of unreacted ammonia and carbon dioxide as a mixed gas from the urea synthesis solution, condensing the mixed gas by indirect heat exchange with the urea synthesis solution from which the mixed gas was separated and that is preferably decompressed to a pressure lower than the urea synthesis pressure, and heating the urea synthesis solution by heat of condensation generated at the time of the condensation of the mixed gas.

Abstract translation: 一种合成尿素的方法，其包括在尿素合成塔的压力下将来自尿素合成塔的尿素合成溶液与原料二氧化碳一起汽提，以将大部分未反应的氨和二氧化碳分离为 来自尿素合成溶液的混合气体，通过与混合气体分离的尿素合成溶液间接热交换将混合气体冷凝，优选减压至低于尿素合成压力的压力，加热尿素合成溶液 通过在混合气体冷凝时产生的冷凝热。

公开(公告)号：US06392096B1

公开(公告)日：2002-05-21

申请号：US09902467

申请日：2001-07-11

Applicant: Johannes H Mennen ,  Kees Jonckers

Inventor： Johannes H Mennen ,  Kees Jonckers

IPC: C07C27304

CPC classification number: C07C273/04

Abstract: The invention relates to a process for the preparation of urea from ammonia and carbon dioxide, the preparation being effected in whole or in part in a vertical combi-reactor. The gas stream leaving the stripper is fed to the condenser section of a vertical combi-reactor in which this gas stream is wholly or partially condensed in the carbamate stream which is transferred from the scrubber section to the condenser section via a downcomer. Ammonia and carbon dioxide are partially converted into urea in this condenser section of the combi-reactor. The urea conversion is completed in the reaction section of the combi-reactor.

Abstract translation: 本发明涉及一种从氨和二氧化碳制备尿素的方法，该方法全部或部分地在立式组合反应器中进行。 离开汽提塔的气流被送入垂直组合反应器的冷凝器部分，其中该气流在氨基甲酸盐流中完全或部分冷凝，氨基甲酸酯流通过降液管从洗涤器部分转移到冷凝器部分。 在组合反应器的冷凝器部分，氨和二氧化碳部分转化为尿素。 尿素转化在组合反应器的反应段中完成。

公开(公告)号：US06344588B1

公开(公告)日：2002-02-05

申请号：US09607325

申请日：2000-06-30

Applicant: Julius G. T. Van Wijck

Inventor： Julius G. T. Van Wijck

IPC: C07C27304

CPC classification number: C07D251/60 ,  C07C273/12 ,  Y02P20/582

Abstract: In the present process for the preparation of urea, an off-gas stream released during the synthesis of melamine in a high-pressure melamine process which consists predominantly of ammonia and carbon dioxide, is introduced into at least one high-pressure section of a urea stripping plant and is used in the synthesis of urea. The off-gas stream can be used directly without any further treatment.

Abstract translation: 在制备尿素的本方法中，在主要由氨和二氧化碳组成的高压三聚氰胺方法中合成三聚氰胺期间释放的废气流被引入至少一个尿素高压段 汽提厂，用于合成尿素。 废气流可以直接使用，无需任何进一步的处理。

公开(公告)号：US06680407B2

公开(公告)日：2004-01-20

申请号：US10239744

申请日：2002-09-26

Applicant: Johannes Henricus Mennen

Inventor： Johannes Henricus Mennen

IPC: C07C27304

CPC classification number: C07C273/04 ,  B01J3/04 ,  B01J2219/00033 ,  B01J2219/00063 ,  B01J2219/00076 ,  B01J2219/00182 ,  B01J2219/00761 ,  B01J2219/185 ,  B01J2219/1943

Abstract: The invention relates to an installation for the preparation of urea from ammonia and carbon dioxide, the installation comprising two reactor sections in a vertically placed combined reactor and a high-pressure condenser section. The installation may comprise a vertically placed combined reactor, with the two reactor sections being separated by a high-pressure condenser section. In another embodiment the installation comprises a vertically placed combined reactor that comprises two reactor sections and a high-pressure condenser section placed outside the reactor. The invention also relates to a process for the preparation of urea in this installation. This involves feeding the gas stream leaving the stripper wholly or partly to the high-pressure condenser section of the installation. Preferably, a portion of the gas stream leaving the scrubber is fed to the second reactor section in the vertically placed combined reactor via an ammonia-driven ejector.

Abstract translation: 本发明涉及一种用于从氨和二氧化碳制备尿素的装置，该装置包括在垂直放置的组合反应器和高压冷凝器部分中的两个反应器部分。 该装置可以包括垂直放置的组合反应器，两个反应器部分由高压冷凝器部分分开。 在另一个实施例中，该装置包括垂直放置的组合反应器，其包括两个反应器部分和放置在反应器外部的高压冷凝器部分。 本发明还涉及在该装置中制备尿素的方法。 这涉及将离开汽提塔的气流全部或部分送入设备的高压冷凝器部分。 优选地，离开洗涤器的气流的一部分经由氨驱动的喷射器进入垂直放置的组合反应器中的第二反应器部分。

公开(公告)号：US06274767B1

公开(公告)日：2001-08-14

申请号：US07987127

申请日：1992-12-08

Applicant: Giorgio Pagani ,  Umberto Zardi

Inventor： Giorgio Pagani ,  Umberto Zardi

IPC: C07C27304

CPC classification number: C07C273/04 ,  B01J2219/00024 ,  Y02P20/142 ,  Y02P20/582

Abstract: Process for the revamping of urea production plants for the synthesis of ammonia (NH3) and carbon dioxide, with a stripping section with NH3, in which the process carries out with differentiated yields, a majority reaction a) between highly pure reagents and a reaction b) between less pure substantially recycled reagents, according to European Patent No. 91116297.2/0479103. According the invention, the urea solution is now fed upstream the stripping section and a reactor with heat removal is utilized. Advantageous, the production capacity of the existing reactor is reduced, with respect to the projected one, in a quantity of 35% to 5%, preferably from 20% to 10%, in favor of the capacity of the “once-through” reactor.

Abstract translation: 用于合成氨（NH 3）和二氧化碳的尿素生产设备的改造工艺，具有NH 3的汽提部分，其中该方法以不同的产率进行，大多数反应a）高纯试剂和反应b ）在较不纯的基本上再循环的试剂之间，根据欧洲专利号91116297.2 / 0479103。 根据本发明，尿素溶液现在被提供在汽提部分的上游，并且使用具有除热的反应器。 有利的是，现有反应堆的生产能力相对于预计的反应堆减少了35％至5％，优选为20％至10％，有利于“一次通过”反应堆的容量 。

公开(公告)号：US06730811B1

公开(公告)日：2004-05-04

申请号：US09586606

申请日：2000-06-02

Applicant: Johannes H. Mennen

Inventor： Johannes H. Mennen

IPC: C07C27304

CPC classification number: C07C273/04

Abstract: The invention relates to a process for the preparation of urea from ammonia and carbon dioxide in which the low-pressure carbamate stream formed in the further upgrading of the urea synthesis solution is stripped in a CO2-carbamate stripper in countercurrent contact with CO2, which results in the formation of a gas mixture consisting substantially of ammonia and carbon dioxide. This gas mixture is preferably subsequently condensed in a high-pressure carbamate condenser and then returned to the synthesis zone.

Abstract translation: 本发明涉及一种从氨和二氧化碳制备尿素的方法，其中在进一步升级尿素合成溶液中形成的低压氨基甲酸酯物流在二氧化碳 - 氨基甲酸酯汽提塔中与二氧化碳反向接触，从而得到结果 在基本上由氨和二氧化碳组成的气体混合物的形成中。优选将该气体混合物随后在高压氨基甲酸铵冷凝器中冷凝，然后返回到合成区。

公开(公告)号：US06586629B1

公开(公告)日：2003-07-01

申请号：US09856193

申请日：2001-05-18

Applicant: Gerhard Coufal

Inventor： Gerhard Coufal

IPC: C07C27304

CPC classification number: C07C273/12

Abstract: The invention relates to a method for producing urea. According to said method, the off-gases which originate from a melamine plant and essentially consist of NH3 and CO2 are introduced into the high-pressure zone of the urea plant by means of ejectors.

Abstract translation: 本发明涉及一种生产尿素的方法。 根据所述方法，源自三聚氰胺装置并且基本上由NH 3和CO 2组成的废气通过喷射器被引入尿素装置的高压区。

公开(公告)号：US06426434B1

公开(公告)日：2002-07-30

申请号：US09984486

申请日：2001-10-30

Applicant: Kinichi Yoshida ,  Kenji Yoshimoto ,  Yasuhiko Kojima

Inventor： Kinichi Yoshida ,  Kenji Yoshimoto ,  Yasuhiko Kojima

IPC: C07C27304

CPC classification number: C07C273/04

Abstract: A urea synthesis process with improved heat economy, wherein a urea synthesis solution obtained by removing most of the unreacted ammonium carbamate by stripping with carbon dioxide at a pressure approximately equal to a urea synthesis pressure is subjected to a high and low pressure decomposition. The gas mixture obtained from the high-pressure decomposition is condensed in at least two steps. Gases obtained from the stripping of the urea synthesis solution, after an initial condensation may be alternatively routed into the high-pressure decomposition column thus facilitating the decomposition of unreacted ammonium carbamate; may be mixed with off-gases from the high-pressure decomposition column and routed to an indirect heat-exchanger for concentrating the aqueous urea solution and facilitating the condensation of the off-gases from the high pressure decomposition column; or may be routed to a condenser for the gas mixture obtained from the high-pressure decomposition after it has underwent indirect heat-exchange with the aqueous urea solution, thus facilitate the further condensation of these gases.

Abstract translation: 具有改善的热效率的尿素合成方法，其中通过用大约等于尿素合成压力的压力用二氧化碳汽提除去大部分未反应的氨基甲酸铵而获得的尿素合成溶液经受高低压分解。 从高压分解得到的气体混合物至少两个步骤冷凝。 在初始冷凝后从尿素合成溶液的汽提中获得的气体可以选择性地送入高压分解塔，从而促进未反应的氨基甲酸铵的分解; 可以与来自高压分解塔的废气混合，并且被引导到用于浓缩尿素水溶液的间接热交换器，并促进来自高压分解塔的废气的冷凝; 或者可以在与尿素水溶液进行间接热交换之后，将其从高压分解获得的气体混合物送至冷凝器，由此促进这些气体的进一步冷凝。

公开(公告)号：US06632967B2

公开(公告)日：2003-10-14

申请号：US10126951

申请日：2002-04-22

Applicant: Jacob F. Scholten ,  Franciscus A. L. Van Laak

Inventor： Jacob F. Scholten ,  Franciscus A. L. Van Laak

IPC: C07C27304

CPC classification number: C07C273/04 ,  G01N2291/02836 ,  Y10T436/171538

Abstract: Process for the preparation of urea from ammonia and carbon dioxide in which the composition of the various process streams is measured via an ultrasonic measuring principle and in which the results of these measurements are used for process control. The process is particularly suitable for continuous measurements in a urea process.

Abstract translation: 用于从氨和二氧化碳制备尿素的方法，其中通过超声波测量原理测量各种工艺流的组成，并将这些测量结果用于过程控制。 该方法特别适用于尿素过程中的连续测量

公开(公告)号：US06552224B2

公开(公告)日：2003-04-22

申请号：US10049687

申请日：2002-05-16

Applicant: Giorgio Pagani ,  Federico Zardi ,  Domenico Romiti

Inventor： Giorgio Pagani ,  Federico Zardi ,  Domenico Romiti

IPC: C07C27304

CPC classification number: C07C273/04 ,  Y02P20/582

Abstract: A process for urea production in a synthesis loop based on CO2 stripping is distinguished by the fact that at least part of a flow recycle carbamate is sent to a treatment of carbamate decomposition and removal of free ammonia to obtain a vapour flow containing CO2 and NH3 with minimum content of water, and a weak water carbamate solution sent back to a urea recovery unit URS and being at least part of above vapour flow containing CO2 and NH3 with minimum content of water directly fed to the bottom zone of a reaction space.