US3468849A - Process for the prevention of build-up of deposits in vapor conduits - Google Patents

Process for the prevention of build-up of deposits in vapor conduits Download PDF

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Publication number
US3468849A
US3468849A US592793A US3468849DA US3468849A US 3468849 A US3468849 A US 3468849A US 592793 A US592793 A US 592793A US 3468849D A US3468849D A US 3468849DA US 3468849 A US3468849 A US 3468849A
Authority
US
United States
Prior art keywords
deposits
glycol
jet
ethylene glycol
vapor
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.)
Expired - Lifetime
Application number
US592793A
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English (en)
Inventor
Horst Rothert
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.)
CHATILLON ITALIANA FIBRE
Chatillon Sa Italiana Per Le Fibre Tessili Artificiali Spa
FISCHER APPARATE ROHR
KARL FISCHER APPARATE und ROHRLEITUNGSBAU
Original Assignee
CHATILLON ITALIANA FIBRE
FISCHER APPARATE ROHR
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 CHATILLON ITALIANA FIBRE, FISCHER APPARATE ROHR filed Critical CHATILLON ITALIANA FIBRE
Application granted granted Critical
Publication of US3468849A publication Critical patent/US3468849A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/78—Preparation processes
    • C08G63/785—Preparation processes characterised by the apparatus used
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
    • B01D5/0003—Condensation of vapours; Recovering volatile solvents by condensation by using heat-exchange surfaces for indirect contact between gases or vapours and the cooling medium
    • B01D5/0021—Vortex
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
    • B01D5/0033—Other features
    • B01D5/0045—Vacuum condensation
    • 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
    • B01J3/00—Processes of utilising sub-atmospheric or super-atmospheric pressure to effect chemical or physical change of matter; Apparatus therefor
    • B01J3/02—Feed or outlet devices therefor
    • 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
    • B01J4/00—Feed or outlet devices; Feed or outlet control devices
    • B01J4/001—Feed or outlet devices as such, e.g. feeding tubes
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F15/00—Other methods of preventing corrosion or incrustation
    • C23F15/005—Inhibiting incrustation
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B31/00—Electric arc lamps
    • H05B31/0003—Electric arc lamps the arc being outside, in the open
    • H05B31/0015—Electric arc lamps the arc being outside, in the open with spare electrodes

Definitions

  • the invention relates to a process for the operation of a jet pump for the conveyance of a substance which has a tendency to form annoying precipitates in a vacuum that are soluble in a non-aqueous solvent.
  • a spray condenser is made use of when the substance to be conveyed is a vaporous medium that becomes precipitated, deposited or condensed in the spray condenser. Through this means there is formed a vacuum through which the medium is drawn, and thus conveyed onward.
  • a jet pump is provided to supplement the condenser, and it serves the purpose of maintaining the vacuum in the spray condenser.
  • the process is also suitable for operating an installation that comprises only the jet pump, without a condenser.
  • Such equipment for conveying the substance is of simple design, without rotating parts, and therefore it makes possible easy control of all parts of the equipment which come into contact with the substance to be conveyed. This advantage is made use of by the chemical industry in particular.
  • the substance to be conveyed is a condensable vapor which contains constituents, impurities, for example, in the form of dust, or that can be condensed or can be Sublimated. Examples of this are impurities which, in the region of moisture saturation, form hydrates.
  • impurities which, in the region of moisture saturation, form hydrates.
  • Disturbing deposits can also be formed from dust, and can cause erosions in the apparatus, particularly in the bends of piping.
  • the substance conveyed forms annoying deposits mainly during a change in its partial pressure and in its concentration in the vacuum stage of the equipment.
  • the fundamental problem solved by the invention is to prevent the formation of such deposits, or precipitates, and particularly cement-like deposits in the jet tube of the jet pump used in conjunction with a poly(ethylene terephthalate) reactor.
  • the invention can be made use of in those cases where the precipitates are soluble in a nonlCC aqueous, alkylene glycol, or one including a cycloaliphatic ring.
  • the process according to the invention can, for example, be applied to equipment wherein the substance to be conveyed is ethylene glycol, which is sucked continuously out of a reactor vessel in which monomeric bis-(2-hydroxyethyl) terephthalate is heated and thereby becomes polymerized, being sucked continuously out of the reactor by a vacuum maintained by a jet pump.
  • the pump jet is formed of vaporized ethylene glycol with or without diluents and in which the undesirable deposits dissolve.
  • the glycol jet that enters the jet pump as a jet of vapor is formed of the same substance that is conveyed by the jet pump; that is, with the preferred example of carrying out the invention, of ethylene glycol. It is, however, also possible to use aliphatic glycols other than ethylene glycol for these jets. Such materials provide a non-aqueous, preferably neutral propellant medium for the vacuum system. Specific examples of such glycols include 1,4-dimethylolcyclohexane, butylene glycol, hexarnethylene glycol, or glycols having side chains, for example, 1,2-propylene glycol or the aforementioned dimethylolcyclohexane.
  • the invention also concerns equipment for carrying out the new process.
  • This equipment is characterized in that, between the suction connections of the jet pump and the reactor vessel is interposed the already-mentioned spray condenser.
  • the vacuum vapor-jet pump can preferably be heated, because cold pump walls would promote a formation of the described deposits.
  • the outlet connectors 3 of the reactor 1 lead to a cylindrical head part 6 of the spray condenser 4.
  • This head part 6 is provided with a heating jacket 7.
  • a rotating shaft 8 carrying a worm 8a that serves for cleaning the inner walls of the head part 6.
  • the head part 6 is open at its bottom, and merges into an inner condenser tube 9, which runs downward and is likewise open at its bottom, and is surrounded by an outer tube 10 of greater diameter. This outer tube runs farther down than the inner tube, and at its bottom runs conically into an outlet opening, to which is connected a barometric outlet tube that is not shown in detail.
  • the tube 10 of the spray-condenser has close below its upper end an outlet 14, which is connected to the head 15 of the jet pump 5.
  • Jet pump is provided with a heating jacket 16, which extends round the head 15 and the jet venturi 17.
  • a jet nozzle 18 directed downward in the axial direction, and it supplies the pumping jet of glycol vapor.
  • the jet pump 5 maintains the vacuum in the spraycondenser 4 and in the reactor 1.
  • the vapors leaving the jet pump are conveyed into a mixed-condensation tank 19. Unprecipitated vapors or gases emerge from an outlet 21; while the liquid ethylene glycol is drawn off from an opening 22 provided at the lower end of the tank 19. This opening is conveniently provided with a barometric leg (not shown).
  • the more or less polymerized substance coming out of the bottom of the reactor 1 can be introduced into a second similar reaction vessel, which forms a second polymerization stage.
  • the product obtained in this way can then be introduced in a third stage into a reactor vessel, corresponding to the one that is illustrated.
  • a quantity of ethylene glycol amounting to 88 kg. hourly is liberated.
  • In the spraycondenser 4 30 kg. hourly of this is separated out.
  • the mixed condenser 19 has a diameter of about 300 mm. and a height of about 1000 mm. Its spray nozzle is fed with 660 kg. of glycol per hour.
  • the jet pump 9 conveys to it a quantity of ethylene glycol vapor amounting to 58 kg. per hour.
  • the water fed to the nozzle of such a steam-jet pump has a temperature of 35 C. and the steam fed to the pump has a pressure of 5 atmospheres gage.
  • the consumption of steam amounts to 20 kg. per hour, and the consumption of water amounts to 250 liters per hour.
  • gage 38 kg. per hour. hour.
  • a further advantage is obtained in that it is now possible to eliminate disturbing waste-water problems. Furthermore, the mixed condenser operated with ethylene glycol condenses and recovers ethylene glycol escaping from the reaction, so that it is merely necessary, in starting up the equipment, to put in the required amount of ethylene glycol.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Gas Separation By Absorption (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US592793A 1965-11-11 1966-11-08 Process for the prevention of build-up of deposits in vapor conduits Expired - Lifetime US3468849A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT2498565 1965-11-11

Publications (1)

Publication Number Publication Date
US3468849A true US3468849A (en) 1969-09-23

Family

ID=11215330

Family Applications (1)

Application Number Title Priority Date Filing Date
US592793A Expired - Lifetime US3468849A (en) 1965-11-11 1966-11-08 Process for the prevention of build-up of deposits in vapor conduits

Country Status (5)

Country Link
US (1) US3468849A (de)
JP (1) JPS4910432B1 (de)
CH (1) CH487345A (de)
GB (1) GB1166094A (de)
NL (1) NL151011B (de)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4011202A (en) * 1974-02-27 1977-03-08 Akzona Incorporated Separating vaporous reaction product in the production of polyesters
US4154921A (en) * 1978-06-19 1979-05-15 E. I. Du Pont De Nemours And Company Preparation of polyesters
US4935171A (en) * 1989-01-27 1990-06-19 Vestar, Inc. Method for vesicle formation
US5466776A (en) * 1994-06-03 1995-11-14 Zimmer Aktiengesellschaft Process for the multistage generation of vacuum for polyester production
US5466765A (en) * 1995-03-09 1995-11-14 Eastman Chemical Company Vaccum system for controlling pressure in a polyester process
US5576414A (en) * 1994-11-15 1996-11-19 Zimmer Aktiengesellschaft Process for generating a vacuum in production of polycarbonate
US6380451B1 (en) * 1999-12-29 2002-04-30 Phillips Petroleum Company Methods for restoring the heat transfer coefficient of an oligomerization reactor
US20040230025A1 (en) * 2000-12-07 2004-11-18 Debruin Bruce Roger Polyester process using a pipe reactor
US6861494B2 (en) 2000-12-07 2005-03-01 Eastman Chemical Company Polyester process using a pipe reactor
US7074879B2 (en) 2003-06-06 2006-07-11 Eastman Chemical Company Polyester process using a pipe reactor
US7135541B2 (en) 2003-06-06 2006-11-14 Eastman Chemical Company Polyester process using a pipe reactor
LT5406B (lt) 2004-02-27 2007-03-26 Zimmer Aktiengesellschaft Būdas ir įrenginys, skirti poliesterių ir kopoliesterių gamybai
US7332548B2 (en) 2004-03-04 2008-02-19 Eastman Chemical Company Process for production of a polyester product from alkylene oxide and carboxylic acid
US7649109B2 (en) 2006-12-07 2010-01-19 Eastman Chemical Company Polyester production system employing recirculation of hot alcohol to esterification zone
US7829653B2 (en) 2007-07-12 2010-11-09 Eastman Chemical Company Horizontal trayed reactor
US7842777B2 (en) 2007-07-12 2010-11-30 Eastman Chemical Company Sloped tubular reactor with divided flow
US7847053B2 (en) 2007-07-12 2010-12-07 Eastman Chemical Company Multi-level tubular reactor with oppositely extending segments
US7858730B2 (en) 2007-07-12 2010-12-28 Eastman Chemical Company Multi-level tubular reactor with dual headers
US7863477B2 (en) 2007-03-08 2011-01-04 Eastman Chemical Company Polyester production system employing hot paste to esterification zone
US7868129B2 (en) 2007-07-12 2011-01-11 Eastman Chemical Company Sloped tubular reactor with spaced sequential trays
US7868130B2 (en) 2007-07-12 2011-01-11 Eastman Chemical Company Multi-level tubular reactor with vertically spaced segments
US7872089B2 (en) 2007-07-12 2011-01-18 Eastman Chemical Company Multi-level tubular reactor with internal tray
US7872090B2 (en) 2007-07-12 2011-01-18 Eastman Chemical Company Reactor system with optimized heating and phase separation
US7943094B2 (en) 2006-12-07 2011-05-17 Grupo Petrotemex, S.A. De C.V. Polyester production system employing horizontally elongated esterification vessel

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102005018843A1 (de) * 2005-04-22 2006-10-26 Zimmer Ag Verfahren und Vorrichtung zur Vakuumerzeugung und Abscheidung von flüchtigen Verbindungen bei Polykondensationsreaktoren

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2793235A (en) * 1954-09-27 1957-05-21 Du Pont Recovery of glycols from polyester production
US3315879A (en) * 1966-04-22 1967-04-25 Irving C Jennings Evacuation system
US3376353A (en) * 1964-06-01 1968-04-02 Monsanto Co Recovery of glycols from polyester production

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2793235A (en) * 1954-09-27 1957-05-21 Du Pont Recovery of glycols from polyester production
US3376353A (en) * 1964-06-01 1968-04-02 Monsanto Co Recovery of glycols from polyester production
US3315879A (en) * 1966-04-22 1967-04-25 Irving C Jennings Evacuation system

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4011202A (en) * 1974-02-27 1977-03-08 Akzona Incorporated Separating vaporous reaction product in the production of polyesters
US4154921A (en) * 1978-06-19 1979-05-15 E. I. Du Pont De Nemours And Company Preparation of polyesters
US4935171A (en) * 1989-01-27 1990-06-19 Vestar, Inc. Method for vesicle formation
US5466776A (en) * 1994-06-03 1995-11-14 Zimmer Aktiengesellschaft Process for the multistage generation of vacuum for polyester production
US5576414A (en) * 1994-11-15 1996-11-19 Zimmer Aktiengesellschaft Process for generating a vacuum in production of polycarbonate
US5466765A (en) * 1995-03-09 1995-11-14 Eastman Chemical Company Vaccum system for controlling pressure in a polyester process
WO1996028246A1 (en) * 1995-03-09 1996-09-19 Eastman Chemical Company Vacuum system for controlling pressure in a polyester process
US5753190A (en) * 1995-03-09 1998-05-19 Eastman Chemical Company Vacuum system for controlling pressure in a polyester process
US6380451B1 (en) * 1999-12-29 2002-04-30 Phillips Petroleum Company Methods for restoring the heat transfer coefficient of an oligomerization reactor
US7420026B2 (en) 2000-12-07 2008-09-02 Eastman Chemical Company Polyester process using a pipe reactor
US7531618B2 (en) 2000-12-07 2009-05-12 Eastman Chemical Company Polyester process using a pipe reactor
US6906164B2 (en) 2000-12-07 2005-06-14 Eastman Chemical Company Polyester process using a pipe reactor
US8114954B2 (en) 2000-12-07 2012-02-14 Grupo Petrotemex, S.A. De C.V. Polyester process using a pipe reactor
US7718759B2 (en) 2000-12-07 2010-05-18 Eastman Chemical Company Polyester process using a pipe reactor
US6861494B2 (en) 2000-12-07 2005-03-01 Eastman Chemical Company Polyester process using a pipe reactor
US7211633B2 (en) 2000-12-07 2007-05-01 Eastman Chemical Company Polyester process using a pipe reactor
US7541423B2 (en) 2000-12-07 2009-06-02 Eastman Chemical Company Polyester process using a pipe reactor
US7345139B2 (en) 2000-12-07 2008-03-18 Eastman Chemical Company Polyester process using a pipe reactor
US20040230025A1 (en) * 2000-12-07 2004-11-18 Debruin Bruce Roger Polyester process using a pipe reactor
US7423109B2 (en) 2000-12-07 2008-09-09 Eastman Chemical Company Polyester process using a pipe reactor
US7446162B2 (en) 2000-12-07 2008-11-04 Eastman Chemical Company Polyester process using a pipe reactor
US7495067B2 (en) 2000-12-07 2009-02-24 Eastman Chemical Company Polyester process using a pipe reactor
US7842778B2 (en) 2000-12-07 2010-11-30 Eastman Chemical Company Polyester process using a pipe reactor
US7135541B2 (en) 2003-06-06 2006-11-14 Eastman Chemical Company Polyester process using a pipe reactor
US7074879B2 (en) 2003-06-06 2006-07-11 Eastman Chemical Company Polyester process using a pipe reactor
LT5406B (lt) 2004-02-27 2007-03-26 Zimmer Aktiengesellschaft Būdas ir įrenginys, skirti poliesterių ir kopoliesterių gamybai
US7332548B2 (en) 2004-03-04 2008-02-19 Eastman Chemical Company Process for production of a polyester product from alkylene oxide and carboxylic acid
US7649109B2 (en) 2006-12-07 2010-01-19 Eastman Chemical Company Polyester production system employing recirculation of hot alcohol to esterification zone
US7943094B2 (en) 2006-12-07 2011-05-17 Grupo Petrotemex, S.A. De C.V. Polyester production system employing horizontally elongated esterification vessel
US8470250B2 (en) 2006-12-07 2013-06-25 Grupo Petrotemex, S.A. De C.V. Polyester production system employing horizontally elongated esterification vessel
US7863477B2 (en) 2007-03-08 2011-01-04 Eastman Chemical Company Polyester production system employing hot paste to esterification zone
US7842777B2 (en) 2007-07-12 2010-11-30 Eastman Chemical Company Sloped tubular reactor with divided flow
US7847053B2 (en) 2007-07-12 2010-12-07 Eastman Chemical Company Multi-level tubular reactor with oppositely extending segments
US7858730B2 (en) 2007-07-12 2010-12-28 Eastman Chemical Company Multi-level tubular reactor with dual headers
US7868129B2 (en) 2007-07-12 2011-01-11 Eastman Chemical Company Sloped tubular reactor with spaced sequential trays
US7868130B2 (en) 2007-07-12 2011-01-11 Eastman Chemical Company Multi-level tubular reactor with vertically spaced segments
US7872089B2 (en) 2007-07-12 2011-01-18 Eastman Chemical Company Multi-level tubular reactor with internal tray
US7872090B2 (en) 2007-07-12 2011-01-18 Eastman Chemical Company Reactor system with optimized heating and phase separation
US7829653B2 (en) 2007-07-12 2010-11-09 Eastman Chemical Company Horizontal trayed reactor

Also Published As

Publication number Publication date
CH487345A (de) 1970-03-15
NL6610502A (de) 1967-05-12
GB1166094A (en) 1969-10-01
NL151011B (nl) 1976-10-15
JPS4910432B1 (de) 1974-03-11

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