CH666197A5 - Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca. - Google Patents

Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca. Download PDF

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Publication number
CH666197A5
CH666197A5 CH3238/85A CH323885A CH666197A5 CH 666197 A5 CH666197 A5 CH 666197A5 CH 3238/85 A CH3238/85 A CH 3238/85A CH 323885 A CH323885 A CH 323885A CH 666197 A5 CH666197 A5 CH 666197A5
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CH
Switzerland
Prior art keywords
height
diameter
cartridge
bed
perforated
Prior art date
Application number
CH3238/85A
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English (en)
Inventor
Umberto Zardi
Original Assignee
Ammonia Casale Sa
Umberto Zardi
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 Ammonia Casale Sa, Umberto Zardi filed Critical Ammonia Casale Sa
Priority to CH3238/85A priority Critical patent/CH666197A5/it
Priority to IN264/CAL/86A priority patent/IN165082B/en
Priority to DE3686783T priority patent/DE3686783T3/de
Priority to EP86104911A priority patent/EP0202454B2/en
Priority to US06/859,044 priority patent/US4755362A/en
Priority to CA000509060A priority patent/CA1277123C/en
Priority to CN86103332.9A priority patent/CN1004611B/zh
Priority to ES554947A priority patent/ES8703812A1/es
Priority to UA4027473A priority patent/UA32508C2/uk
Priority to US07/210,868 priority patent/US4952375A/en
Priority to US07/214,582 priority patent/US4904453A/en
Publication of CH666197A5 publication Critical patent/CH666197A5/it

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
    • C01C1/00—Ammonia; Compounds thereof
    • C01C1/02—Preparation, purification or separation of ammonia
    • C01C1/04—Preparation of ammonia by synthesis
    • C01C1/0405—Preparation of ammonia by synthesis from N2 and H2 in presence of a catalyst
    • C01C1/0417—Preparation of ammonia by synthesis from N2 and H2 in presence of a catalyst characterised by the synthesis reactor, e.g. arrangement of catalyst beds and heat exchangers in the reactor
    • C01C1/0423—Cold wall reactors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B01J8/0403—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the fluid flow within the beds being predominantly horizontal
    • B01J8/0423—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the fluid flow within the beds being predominantly horizontal through two or more otherwise shaped beds
    • B01J8/0426—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the fluid flow within the beds being predominantly horizontal through two or more otherwise shaped beds the beds being superimposed one above the other
    • B01J8/0434—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the fluid flow within the beds being predominantly horizontal through two or more otherwise shaped beds the beds being superimposed one above the other in combination with two or more cylindrical annular shaped beds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B01J8/0446—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical
    • B01J8/0449—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical in two or more cylindrical beds
    • B01J8/0453—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical in two or more cylindrical beds the beds being superimposed one above the other
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B01J8/0446—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical
    • B01J8/0461—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical in two or more cylindrical annular shaped beds
    • B01J8/0469—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds the flow within the beds being predominantly vertical in two or more cylindrical annular shaped beds the beds being superimposed one above the other
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/04—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid passing successively through two or more beds
    • B01J8/0496—Heating or cooling the reactor
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/15—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively
    • C07C29/151—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases
    • C07C29/152—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases characterised by the reactor used
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
    • B01J2208/00008—Controlling the process
    • B01J2208/00017—Controlling the temperature
    • B01J2208/00106—Controlling the temperature by indirect heat exchange
    • B01J2208/00168—Controlling the temperature by indirect heat exchange with heat exchange elements outside the bed of solid particles
    • B01J2208/00194—Tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/026—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits
    • 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
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Analytical Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)

Description

666 197
2

Claims (1)

  1. RIVENDICAZIONE Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca: consistenti di un mantello esterno (P), in genere in corpo unico, e di una cartuccia interna (C) avente diametro (Di) e contenente catalizzatore in granuli disposto in uno o più catalitici (K) che hanno altezza assiale (Hi) e sono racchiusi tra una parete esterna cilidrica, una parete interna cilindrica, un tubo interno di trasferimento del gas fresco di sintesi (T) ed un fondo (FO), la faccia trasversale superiore di ciascun letto essendo aperta ed investita assialmente dal gas di sintesi, caratterizzato dal fatto che la parete più interna (Fi) di diametro (D'e) è ora perforata su tutta l'altezza (Hi) del letto catalitico, la parete esterna (Fe) è perforata su una sua porzione maggioritaria di altezza (H' i < Hi) e di diametro (D'i) inferiore al diametro (Di) della cartuccia, ed è priva di perforazioni sulla rimanente porzione di altezza (Hi-H' i) e di diametro uguale a quello (Di) della cartuccia, il fondo di ogni letto essendo saldato da un anello di saldatura al tubo di trasferimento del gas (T).
    DESCRIZIONE
    La presente invenzione si riferice ad un reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee in particilare dell'ammoniaca, consistenti di un mantello esterno (P), in genere in corpo unico, e di una cartuccia interna (C) avente diametro (Di) e contenente catalizzatore in granuli disposto in uno o più letti catalitici (K) che hanno altezza assiale (Hi) e sono racchiusi tra una parete cilindrica esterna, una parete cilindrica interna, un tubo centrale di trasferimento del gas fresco di sintesi (T) avente diametro (De) (piccolo rispetto a quello Di della cartuccia), ed un fondo (FO), la faccia trasversale superiore di ciascun letto essendo aperta ed investita assialmente dal gas di sintesi.
    Reattori del tipo sopra precisato sono stati recentemente descritti dai Richiedenti.
    Nella continuazione delle loro ricerche in questo importante settore della tecnica, i detti Richiedenti hanno, non senza sorpresa, trovato e messo a punto una nuova forma di realizzazione che consente di ottenere valori ottimali nel processo e nella costruzione.
    Il metodo secondo la presente invenzione si caratterizza ora per il fatto che la parete più interna (Fi) di diametro (D'e) è ora perforata su tutta l'altezza (Hi) del letto catalitico, la parete esterna (Fe) è perforata su una sua porzione maggioritaria di altezza (H'i < Hi) e di diametro (D'i) inferiore al diametro (Di) della cartuccia, ed è priva di perforazioni sulla rimanente porzione di altezza (Hi-H' i) e di diametro uguale a quello (Di) della cartuccia, il fondo di ogni letto essendo saldato da un anello 5 di saldatura al tubo di trasferimento del gas (T).
    I diversi aspetti e vantaggi dell'invenzione appariranno meglio dalla descrizione seguente della forma di realizzazione rappresentata nella figura unica allegata, che è una sezione schematica longitudinale di un reattore per la sintesi dell'ammo-
    ìo niaca.
    Come si vede è ora la parete più interna (Fi) di diametro (D'i) (inferiore a quelli Di della cartuccia C) e di altezza (Hi), ad essere quella maggiormente (se non totalmente) perforata mentre la parete esterna (Fe) del letto è perforata sull'altezza i5 (H' i) (inferiore ad Hi) di diametro (D'i) ed è imperforata sull'altezza (Hi-H' i) avente diametro (Di) uguale a quello interno della cartuccia (C); anzi si può dire che il letto catalitico (K) sull'altezza (Hi-H'i) si allarga verso l'esterno sulla cartuccia (C) che così la chiude rendendola imperforata su tratto superiore 20 (Hi-H' i) sporgente da (Fe). Il fondo (FO) di ogni cartuccia è ora saldato al tubo interno (T) con la saldatura anulare (SAi).
    Come si vede dalla figura, il gas fresco entra ancora dal fondo del reattore (flusso 1), attraverso l'intercapedine (E) dal basso verso l'alto, passa nello scambiatore (S), entra assialmen-25 te sulla faccia superiore aperta (Al) del primo letto catalicito (I) e lo attraversa sempre assialmente dall'alto in basso sulla porzione sporgente (SPO) di altezza (Hi-H'i) (freccia 5).
    II flusso di gas fresco penetra altresì nell'intercapedine (6) tra (Fi) e (T) e per effetto delle perforazioni su (Fi) e (Fe) come
    30 pure per la chiusura del fondo (FO) con l'anello di saldatura (SAi) il gas attraversa ora secondo le frecce 2, cioè radialmente ma dall'interno verso l'esterno, la porzione forata di (Fe) avente altezza (H' i) e seguendo le frecce 3 passa sul successivo letto catalitico (II) che attraversa dapprima assialmente sul tratto 35 sporgente (SPO) di altezza (Hi-H' i) e poi radialmente ma dall'interno verso l'esterno di tutta l'altezza (H'i), raccogliendosi nell'intercapedine (Q) tra parete esterna (Fe) e cartuccia (C), dalla quale passa sul terzo letto (III) e così via.
    I letti possono avere dimensioni diverse in particolare cre-4o scenti dall'alto in basso, possono essere dotati di regolatori di flusso (ad esempio di una rete) e/o di almeno uno strato di catalizzatore e granulometria differenziata.
    I vantaggi dell'invenzione sono in ordine processuale e costruttivo, in particolare portano a valori ottimali nella riduzione 45 dei consumi, nelle rese e nelle strutture, rapidità e facilità di costruzione o transformazione dei reattori. Ad esempio questi vantaggi si accentuano nei reattori a grandi diametri.
    v
    1 foglio disegni
CH3238/85A 1985-05-15 1985-07-25 Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca. CH666197A5 (it)

Priority Applications (11)

Application Number Priority Date Filing Date Title
CH3238/85A CH666197A5 (it) 1985-07-25 1985-07-25 Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca.
IN264/CAL/86A IN165082B (it) 1985-05-15 1986-04-02
DE3686783T DE3686783T3 (de) 1985-05-15 1986-04-10 Verfahren zum Herabsetzen des Energieverbrauchs von Reaktoren für die heterogenen katalytischen Synthesen.
EP86104911A EP0202454B2 (en) 1985-05-15 1986-04-10 Method for retrofitting a bottleneck-shaped heterogeneous synthesis reactor
US06/859,044 US4755362A (en) 1985-05-15 1986-05-02 System for reducing energy consumption improving reactors for heterogeneous catalytic synthesis and relative reactors
CA000509060A CA1277123C (en) 1985-05-15 1986-05-13 System for reducing energy consumption improving reactors for heterogeneous catalytic synthesis and relative reactors
CN86103332.9A CN1004611B (zh) 1985-05-15 1986-05-14 改进非均相催化合成反应器以降低能量消耗的系统及其相应的反应器
ES554947A ES8703812A1 (es) 1985-05-15 1986-05-14 Perfeccionamientos en un sistema para aumentar el rendimiento de conversion y reducir el consumo de energia en reactores de sintesis heterogenea
UA4027473A UA32508C2 (uk) 1985-05-15 1986-05-14 Спосіб модифікації реактора аксіального типу для гетерогенного синтезу в реактор аксіально-радіального або радіального типу
US07/210,868 US4952375A (en) 1985-05-15 1988-06-24 System for reducing energy consumption improving reactors for heterogeneous catalytic synthesis and related reactors
US07/214,582 US4904453A (en) 1985-05-15 1988-07-01 System for reducing energy consumption improving reactors for heterogeneous catalytic synthesis and relative reactors

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH3238/85A CH666197A5 (it) 1985-07-25 1985-07-25 Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca.

Publications (1)

Publication Number Publication Date
CH666197A5 true CH666197A5 (it) 1988-07-15

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Application Number Title Priority Date Filing Date
CH3238/85A CH666197A5 (it) 1985-05-15 1985-07-25 Reattore per aumentare la resa di conversione e ridurre i consumi energetici nelle sintesi eterogenee dell'ammoniaca.

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CH (1) CH666197A5 (it)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2137538C1 (ru) * 1993-10-29 1999-09-20 Аммониа Казале С.А. Способ модернизации реактора для гетерогенного экзотермического синтеза и способ повышения его эффективности
RU2154524C2 (ru) * 1993-12-29 2000-08-20 Аммониа Казале С.А. Способ модернизации на месте реактора гетерогенного экзотермического синтеза, в особенности так называемого реактора келлога, реактор гетерогенного экзотермического синтеза и способ осуществления высокопроизводительных гетерогенных реакций

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2137538C1 (ru) * 1993-10-29 1999-09-20 Аммониа Казале С.А. Способ модернизации реактора для гетерогенного экзотермического синтеза и способ повышения его эффективности
RU2154524C2 (ru) * 1993-12-29 2000-08-20 Аммониа Казале С.А. Способ модернизации на месте реактора гетерогенного экзотермического синтеза, в особенности так называемого реактора келлога, реактор гетерогенного экзотермического синтеза и способ осуществления высокопроизводительных гетерогенных реакций

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