DE2411205A1 - PROCESS FOR PURIFYING THE SOLUTIONS OF NH LOW 3 AND CARBAMATE FROM A UREA SYNTHESIS ACTUATOR - Google Patents

PROCESS FOR PURIFYING THE SOLUTIONS OF NH LOW 3 AND CARBAMATE FROM A UREA SYNTHESIS ACTUATOR

Info

Publication number
DE2411205A1
DE2411205A1 DE2411205A DE2411205A DE2411205A1 DE 2411205 A1 DE2411205 A1 DE 2411205A1 DE 2411205 A DE2411205 A DE 2411205A DE 2411205 A DE2411205 A DE 2411205A DE 2411205 A1 DE2411205 A1 DE 2411205A1
Authority
DE
Germany
Prior art keywords
carbamate
solutions
urea
purifying
actuator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
DE2411205A
Other languages
German (de)
Other versions
DE2411205B2 (en
DE2411205C3 (en
Inventor
Vincenzo Dr Lagana
Umberto Dr Zardi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SnamProgetti SpA
Original Assignee
SnamProgetti SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SnamProgetti SpA filed Critical SnamProgetti SpA
Publication of DE2411205A1 publication Critical patent/DE2411205A1/en
Publication of DE2411205B2 publication Critical patent/DE2411205B2/en
Application granted granted Critical
Publication of DE2411205C3 publication Critical patent/DE2411205C3/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
    • C07C273/02—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds
    • C07C273/14—Separation; Purification; Stabilisation; Use of additives
    • C07C273/16—Separation; Purification
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/141—Feedstock

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Description

Verfahren zur Reinigung der aus einem Harnstoffsynthese-Process for the purification of the urea synthesis

Die Erfindung "betrifft ein Verfahren zur Reinigung der einen Harnstoffsynthesereaktor verlassenden Lösungen von NH^ und Carbamat.The invention "relates to a method for purifying the one Urea synthesis reactor leaving solutions of NH ^ and Carbamate.

Die vorstehend "bezeichneten Lösungen enthalten Harnstoff, Carbamat, Wasser und NH^. Zur Reinigung dieser Lösungen werden gewöhnlich viele Systeme verwendet, unter ihnen die Destillation in einer Kolonne oder in üblichen Wärmeaustauschern oder Filmwärmeaustauschern, wobei es auch möglich ist, Abstreifmittel (stripping agents) zur Entfernung der bei der Zersetzung von Ammoniumcarbamat erzeugten Gase zu verwenden. Bei solchen Methoden ist die restliche Carbamatmenge in der Harnstofflösung immer derart, daß weitere Reinigungsstufen erforderlich sind.The solutions described above contain urea, Carbamate, water and NH ^. To purify these solutions will be many systems are usually used, among them column distillation or conventional heat exchangers or film heat exchangers, although it is also possible to use stripping agents to remove the Decomposition of ammonium carbamate generated gases to use. With such methods, the remaining amount of carbamate in the urea solution is always such that further purification steps required are.

409839/1025409839/1025

2C112052C11205

Als Gegenstand der vorliegenden Erfindung wurde gefunden, daß es zur Erzielung einer praktisch von Ammoniumcarbamat freien Harnstofflösung notwendig ist auf die Gase, die sich aus der Lösung entwickeln durch eine Verminderung der Kontaktzeit zwischen diesen Gasen und der Flüssigkeit einzuwirken, wobei als Endergebnis eine gasförmige Phase erhalten wird, die sich mit der flüssigen Phase nicht im Gleichgewicht befindet. Die Kontaktzeiten zwischen den sich bei dem Destillationsarbeitsgang entwickelnden Gasen und der gleichzeitig anwesenden Flüssigkeit muß unter 60 Sekunden (60'') vorzugsweise unter 30 Sekunden (3011) gehalten werden, um zwischen der Flüssigkeit und den Gasen Bedingungen für das Nichtvorhanden-sein eines Gleichgewichts (non-equilibrium conditions) zu erzielen. Es ist ersichtlich, daß der Destillationsarbeitsgang mit jeder üblichen bekannten Vorrichtung durchgeführt werden kann, vorausgesetzt, daß die Kontaktzeiten innerhalb der vorstehenden Grenzen gehalten werden.As an object of the present invention it has been found that in order to obtain a urea solution practically free of ammonium carbamate it is necessary to act on the gases evolving from the solution by reducing the contact time between these gases and the liquid, the end result being a gaseous phase which is not in equilibrium with the liquid phase. The contact times between the gases evolving during the distillation operation and the liquid present at the same time must be kept below 60 seconds (60 "), preferably below 30 seconds (30 11 ), in order to ensure that there is no equilibrium between the liquid and the gases (non-equilibrium conditions). It will be seen that the distillation operation can be carried out by any conventional apparatus provided that the contact times are kept within the above limits.

Die folgenden Beispiele dienen zur Erläuterung der Erfindung, ohne sie zu beschränken.The following examples serve to illustrate the invention without restricting it.

Beispiel 1example 1

In ein Flash-System (Entspannungssystem) wie dem in der Figur 1 gezeigten, wurde eine Harnstofflösung (1) der folgenden Zusammensetzung eingespeist:
Harnstoff: 33,3 %
Wasser: 18,1 %
.Ammoniumcarbamat 31,9 %
NH3: 16,7 % A urea solution (1) of the following composition was fed into a flash system (relaxation system) such as that shown in FIG. 1:
Urea: 33.3%
Water: 18.1 %
Ammonium carbamate 31.9%
NH 3 : 16.7 %

Das Flash-(bzw.Entspannungs)gefäß hatte 3Böaen Q11^ ej_n "Thermosiphon-Zirkulations system" durch ein WärmBelement 3· Die Geschwindigkeit der Flüssigkeit in dem Thermosiphonumlauf betrug 3 m/sec., so daß die Kontaktzeit zwischen der Flüssigkeit und dem Gas 15 see. betrug.The flash (or relaxation) vessel had 3 Boaen Q 11 ^ e j_ n "Thermosiphon circulation system" through a heating element 3 · The speed of the liquid in the thermosiphon circulation was 3 m / sec., So that the contact time between the liquid and the gas 15 see. fraud.

Die Zusammensetzung der Harnstofflösung (2), die das Entspannungsgefäß verließ, war:
Harnstoff: 67,5 %
Wasser: 31,0 %The composition of the urea solution (2) leaving the expansion vessel was:
Urea: 67.5%
Water: 31.0%

409839/1025409839/1025

1,5%1.5%

Carbamat: vernachlässigbar Das Flash-System arbeitete bei einer Temperatur von 200° undCarbamate: negligible The flash system worked at a temperature of 200 ° and

einem Druck von 140 kg/cma pressure of 140 kg / cm

Beispiel 2Example 2

Zum Kopf einer Destillationskolonne (Figur 2) mit 15 Böden und einer Verweilzeit der Flüssigkeit an jedem Boden von 10 see. wurde eine Harnstofflösung (1) der folgenden Zusammensetzung eingespeist:
Harnstoff: 30,0 % Wasser: 17,6 % Carbamat: 24,1 % NH3: 28,3 %To the top of a distillation column ( Figure 2 ) with 15 trays and a residence time of the liquid on each tray of 10 seconds. a urea solution (1) of the following composition was fed:
Urea: 30.0% Water: 17.6 % Carbamate: 24.1 % NH 3 : 28.3%

Der Fuß der Kolonne wurde mit Heizvorrichtungen bzw. Heizmitteln auf eine Temperatur' von 21O°C gebracht.The base of the column was brought to a temperature of 210 ° C. with heating devices or heating means.

Der Druck am Fuß bzw. am unteren Ende der Kolonne betrugThe pressure at the foot or at the lower end of the column was

2
130 kg/cm . Die Temperatur der die Kolonne verlassenden Gase betrug 1900C. Als Kontaktzeit zwischen Flüssigkeit und Gas resultierten 10 see.2
130 kg / cm. The temperature of the gases leaving the column was 190 ° C. The contact time between liquid and gas resulted in 10 seconds.

Die Zusammensetzung der die Kolonne verlassenden Harnstofflösung (2) war:The composition of the urea solution leaving the column (2) was:

Harnstoff: 65,3 % Urea: 65.3 %

Wasser: 32,7 % Water: 32.7 %

Carbamat: vernachlässigbarCarbamate: negligible

409839/1025409839/1025

Claims (2)

PatentansprücheClaims 1. Verfahren zur-Reinigung von einen Harnstoffsynthesereaktor verlassenden Harnstofflösungen, von ML und Carbamat durch einen Destillationsvorgang mit Abtrennung einer flüssigen Phase und gasförmigen Phase, dadurch gekennzeichnet, daß die Kontaktzeit zwischen der flüssigen Phase und der gasförmigen Phase, die sich in ihrer Anwesenheit entwickelt, unter 60 see. liegt.1. Method for cleaning a urea synthesis reactor leaving urea solutions, by ML and carbamate a distillation process with separation of a liquid phase and a gaseous phase, characterized in that the contact time between the liquid phase and the gaseous phase that develops in their presence, under 60 see. lies. 2. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, daß die Kontaktzeit unter 30 see. liegt.2. The method according to claim 1, characterized in that the contact time is less than 30 seconds. lies. 409839/1025409839/1025
DE19742411205 1973-03-08 1974-03-08 Process for obtaining a urea solution practically free of ammonium carbonate from the effluent of a urea synthesis device Expired DE2411205C3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT21300/73A IT981191B (en) 1973-03-08 1973-03-08 PROCEDURE FOR PURIFICATION FROM NH 3 AND CARBAMATE OF THE SOLUTION OUT OF A SINTE SI REACTOR OF THE URE
IT2130073 1973-03-08

Publications (3)

Publication Number Publication Date
DE2411205A1 true DE2411205A1 (en) 1974-09-26
DE2411205B2 DE2411205B2 (en) 1976-01-15
DE2411205C3 DE2411205C3 (en) 1976-09-09

Family

ID=

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3753619A1 (en) 2019-06-18 2020-12-23 SKW STICKSTOFFWERKE PIESTERITZ GmbH Method for the continuous production of pure urea solutions by recycling process water

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3753619A1 (en) 2019-06-18 2020-12-23 SKW STICKSTOFFWERKE PIESTERITZ GmbH Method for the continuous production of pure urea solutions by recycling process water

Also Published As

Publication number Publication date
GB1402249A (en) 1975-08-06
TR17998A (en) 1976-08-20
JPS56134344U (en) 1981-10-12
ZA741186B (en) 1975-01-29
LU69576A1 (en) 1974-07-05
PH12740A (en) 1979-08-09
ES424334A1 (en) 1976-06-01
AT342067B (en) 1978-03-10
FR2220516A1 (en) 1974-10-04
IE38973L (en) 1974-09-08
EG11031A (en) 1976-11-30
MW874A1 (en) 1975-05-13
DE2411205B2 (en) 1976-01-15
NL7403054A (en) 1974-09-10
DK144008C (en) 1982-04-26
IT981191B (en) 1974-10-10
IN139208B (en) 1976-05-22
BR7401582D0 (en) 1974-11-05
FR2220516B1 (en) 1978-01-06
ZM4274A1 (en) 1974-11-21
AU6594074A (en) 1975-08-28
CA1022103A (en) 1977-12-06
JPS49124029A (en) 1974-11-27
CH603565A5 (en) 1978-08-31
DD112752A5 (en) 1975-05-05
AR200429A1 (en) 1974-11-08
DK144008B (en) 1981-11-16
BE811880A (en) 1974-07-01
ATA189874A (en) 1977-07-15
RO69510A (en) 1980-12-30
SE386145B (en) 1976-08-02
IE38973B1 (en) 1978-07-05

Similar Documents

Publication Publication Date Title
EP0107046B1 (en) Process for the removal of co2 and, when present, h2s from natural gases
DE60013207T2 (en) Carbon dioxide production with composite amine mixtures
EP0126288A2 (en) Method of carrying out chemical reactions and for the simultaneous fractionation of a mixture into several fractions by a distillation column
EP0054607B1 (en) Process for eliminating ammonium nitrate from aqueous solutions
DE1592534A1 (en) Process for the production of uranyl fluoride
DE2411205A1 (en) PROCESS FOR PURIFYING THE SOLUTIONS OF NH LOW 3 AND CARBAMATE FROM A UREA SYNTHESIS ACTUATOR
DE945239C (en) Process for the production of cyanuric chloride
DE1244746B (en) Process for the separation of the ammonia produced in medium and low pressure synthesis plants
DE139601T1 (en) METHOD AND DEVICE FOR CONCENTRATING AQUEOUS ETHYLENE OXIDE SOLUTIONS.
DE1948426C3 (en) Process for the production of hydrogen sulfide and ammonia from an aqueous solution
DE2411205C3 (en) Process for obtaining a urea solution practically free of ammonium carbonate from the effluent of a urea synthesis device
DE1195283B (en) Process for the production of ammonia from coke oven gases
DE2938424C2 (en) Process for the separation of acids and bases passing over with distillate vapors
DE1618385B2 (en) METHODS AND DEVICES FOR THE EXTRACTION OF AZINES AND / OR. OR HYDRAZONES FROM THESE MIXTURES
DE4226905A1 (en) Process for carrying out distillative separations in a batch mode
DE1279009B (en) Process for the separation of adipic dinitrile
DE886893C (en) Process for the production of hydrogen halide solutions
DE1049833B (en) Process for removing acetone from aqueous hydrazine solutions containing acetone
DE2057793A1 (en) Process for the separation of acid mixtures
DE1254134B (en) Process for the enrichment of deuterium with respect to its isotopes according to the bit temperature exchange method
DE1186848B (en) Process for the separation of vinyl fluoride-acetylene mixtures
AT226207B (en) Process for the isolation of highly concentrated isoprene
DE925644C (en) Process for the production of hydrogen cyanide
DE440607C (en) Method and device for the synthetic production of ammonia
DE1468245C (en) Process for the production of urea from ammonia and carbon dioxide with two distillation stages

Legal Events

Date Code Title Description
C3 Grant after two publication steps (3rd publication)
E77 Valid patent as to the heymanns-index 1977
8339 Ceased/non-payment of the annual fee