US20060024214A1 - Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors - Google Patents

Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors Download PDF

Info

Publication number
US20060024214A1
US20060024214A1 US09/849,678 US84967805A US2006024214A1 US 20060024214 A1 US20060024214 A1 US 20060024214A1 US 84967805 A US84967805 A US 84967805A US 2006024214 A1 US2006024214 A1 US 2006024214A1
Authority
US
United States
Prior art keywords
flange
fluidized bed
provision
bed reactors
manhole
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.)
Abandoned
Application number
US09/849,678
Inventor
Unterschrift Erfinders
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.)
ThyssenKrupp Industrial Solutions AG
Original Assignee
Uhde GmbH
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
Assigned to KRUPP UHDE GMBH reassignment KRUPP UHDE GMBH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SCHON, HARTMUT
Assigned to UHDE GMBH reassignment UHDE GMBH CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: KRUPP UHDE GMBH
Application filed by Uhde GmbH filed Critical Uhde GmbH
Publication of US20060024214A1 publication Critical patent/US20060024214A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • 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
    • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
    • B01J8/1872—Details of the fluidised bed reactor
    • 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
    • B01J8/0015—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor
    • B01J8/003—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor in a downward flow
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
    • C07C17/15—Preparation of halogenated hydrocarbons by replacement by halogens with oxygen as auxiliary reagent, e.g. oxychlorination
    • C07C17/152—Preparation of halogenated hydrocarbons by replacement by halogens with oxygen as auxiliary reagent, e.g. oxychlorination of hydrocarbons
    • C07C17/156—Preparation of halogenated hydrocarbons by replacement by halogens with oxygen as auxiliary reagent, e.g. oxychlorination of hydrocarbons of unsaturated hydrocarbons

Definitions

  • the invention relates to an apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors for the oxychlorination of ethylene, oxygen and HCl, having a wall flange fixed in the reactor wall.
  • oxychlorination ethylene, oxygen and HCl ar reacted in a fluidized bed reactor (oxyreactor) over a copper-containing catalyst to give 1,2-dichloroethane and water.
  • a fluidized bed reactor oxygen and HCl
  • catalyst deposits may occur in any dead spaces within the reactor.
  • the presence of HCl results in the formation of hydrochloric acid when the temperature falls below the dew point, and hence causes severe corrosion.
  • Particularly at risk here are dead spaces in the shell region, such as any manholes an measuring ports. Attempts have been made to remedy this disadvantage by, for example, providing heated flushing lines at all measuring ports, in order also to prevent adverse effects on measurements and temperatures falling below the dew point.
  • the invention entails a number of advantages, for example in that possible dead spaces in which catalyst deposits may be formed are reduced and all heated flushing lines that are employed in the conventional solutions, with filter stations, flowmeters, condensate collectors, mountings and the like, are eliminated,
  • the surface bevel is so great, at least in its area that is lowest in the direction of gravity, that deposition of catalyst granules or the like is prevented.
  • the bevel of the surface is designed to increase, beginning from the horizontal median plane in the inner edge region toward the vertical center of the flange ring.
  • FIG. 1 shows a simplified perspective view of a block flange according to the invention
  • FIG. 2 shown a simplified sectional view of a manhole
  • FIG. 3 shows a simplified sectional view of a block flange approximately in accordance wits FIG. 1 .
  • a block flange generally designated 1 is welded into a reactor wall 2 .
  • the block flange has a certain cylindrical extent and has a passage aperture 3 , for example for a measuring instrument, a probe or the like.
  • the flange inner surface 4 is beveled, the bevel being designated 5 in FIG. 1 .
  • This beveled surface 5 begins approximately at the center horizontal line 6 of the flange 1 , extends as far ae the horizontal center, designated 7 , of the flange and from there onward to the vertical center 6 , so that a form of slide results. Material falling thereon is automatically rejected as a result of gravity.
  • FIG. 2 shows a manhole design, and here again a corresponding flange design is shown, the manhole hoeing closed by a cover designated in this case 8 .
  • FIG. 3 shows a block flange 1 of this type in section.
  • the flange 1 or 1 a can, in particular, be welded in flush with the inner wall surface of the reactor wall 2 , the flange or flange bore 3 can be arranged at a slightly downward-pointing angle to assist the sliding-off of material falling thereon, and so on.
  • the invention relates to an apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors for the oxychlorination of ethylene, oxygen and HCl, having a wall flange fixed in the reactor wall.
  • oxychlorination ethylene, oxygen and HCl are reacted in a fluidized bed reactor (oxyreactor) over a copper-containing catalyst to give 1,2-dichloroethane and water.
  • a fluidized bed reactor oxygen and HCl
  • catalyst deposits may occur in any dead spaces within the reactor.
  • the presence of HCl results in the formation of hydrochloric acid when the temperature falls below the dew point, and hence causes severe corrosion.
  • Particularly at risk here are dead spaces in the shell region, such as any manholes and measuring ports. Attempts have been made to remedy this disadvantage by, for example, providing heated flushing lines at all measuring ports, in order also to prevent adverse effects on measurements and temperatures falling below the dew point.
  • the invention entails a number of advantages, for example in that possible dead spaces in which catalyst deposits may be formed are reduced and all heated flushing lines that are employed in the conventional solutions, with filter stations, flowmeters, condensate collectors, mountings and the like, are eliminated.
  • the surface bevel is so great, at least in its area that is lowest in the direction of gravity, that deposition of catalyst granules or the like is prevented.
  • the bevel of the surface is designed to increase, beginning from the horizontal median plane in the inner edge region toward the vertical center of the the flange ring.
  • FIG. 1 shows a simplified perspective view of a block flange according to the invention
  • FIG. 2 shows a simplified sectional view of a manhole
  • FIG. 3 shows a simplified sectional view of a block flange approximately in accordance with FIG. 1 .
  • a block flange generally designated A) 1 is welded into a reactor wall 2 .
  • the block flange has a certain cylindrical extent and has a passage aperture 3 , for example for a measuring instrument, a probe or the like.
  • the flange inner surface 4 is beveled, the bevel being designated 5 in FIG. 1 .
  • This beveled surface 5 begins approximately at the center horizontal line 6 of the flange 1 , extends as far as the horizontal center, designated 7 , of the flange and from there onward to the vertical center 6 , so that a form of slide results. Material falling thereon is automatically rejected as a result of gravity.
  • FIG. 2 shows a manhole design, and here again a corresponding flange design is shown, the manhole being closed bat a cover designated in this case 8 .
  • FIG. 3 shows a block flange 1 of this type in section.
  • the flange 1 or 1 a can, in particular, be welded in flush with the inner wall surface of the reactor wall 2 , the flange or flange bore 3 can be arranged at a slightly downward-pointing Q angle to assist the sliding-off of material falling thereon, and so on.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
  • Underground Structures, Protecting, Testing And Restoring Foundations (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

An apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors for the oxychlorination of ethylene, oxygen and HCl, having a wall flange fixed in the reactor wall, is intended to provide a solution whereby all other auxiliary measures can be dispensed with and the expense associated therewith can be eliminated without the functionality of the system suffering as a result and without undesirable deposits being formed in these areas.
This is achieved in that the flange surface (5) pointing inward and downward in the direction of gravity is of beveled designs at least in some areas.

Description

  • The invention relates to an apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors for the oxychlorination of ethylene, oxygen and HCl, having a wall flange fixed in the reactor wall.
  • In what is known as oxychlorination, ethylene, oxygen and HCl ar reacted in a fluidized bed reactor (oxyreactor) over a copper-containing catalyst to give 1,2-dichloroethane and water. In operation, and when the plant is shut down, catalyst deposits may occur in any dead spaces within the reactor. The presence of HCl results in the formation of hydrochloric acid when the temperature falls below the dew point, and hence causes severe corrosion. Particularly at risk here are dead spaces in the shell region, such as any manholes an measuring ports. Attempts have been made to remedy this disadvantage by, for example, providing heated flushing lines at all measuring ports, in order also to prevent adverse effects on measurements and temperatures falling below the dew point.
  • With manhole designs, it is known to equip the lids of said manholes internally with an additional displacement body which is so designed ms to produce the smoothest possible flush transition to the inner surface of the reactor shell.
  • It is an object of the invention to provide a solution whereby all other auxiliary measures can be dispensed with and the expense associated therewith can be eliminated without the functionality of the system suffering as a result and without undesirable deposits being formed in these areas.
  • This object is achieved, according to the invention, with an apparatus of the type described initially in that the flange surface pointing inward and downward in the direction of gravity is of beveled design, at least in some areas.
  • The invention entails a number of advantages, for example in that possible dead spaces in which catalyst deposits may be formed are reduced and all heated flushing lines that are employed in the conventional solutions, with filter stations, flowmeters, condensate collectors, mountings and the like, are eliminated,
  • In an embodiment, it is envisaged that the surface bevel is so great, at least in its area that is lowest in the direction of gravity, that deposition of catalyst granules or the like is prevented.
  • It is particularly advantageous it, as the invention likewise envisages, the bevel of the surface is designed to increase, beginning from the horizontal median plane in the inner edge region toward the vertical center of the flange ring.
  • With this design, a smooth, homogeneous, funnel-like slide is formed, directed toward the interior of the reactor, so that, for example, when the reactor is switched off and the fluidized bed sinks, the deposition of catalyst material or the like is reliably prevented.
  • Further features, details and advantages of the invention are apparent from the description that follows and from reference to the drawing, in which:
  • FIG. 1 shows a simplified perspective view of a block flange according to the invention,
  • FIG. 2 shown a simplified sectional view of a manhole,
  • FIG. 3 shows a simplified sectional view of a block flange approximately in accordance wits FIG. 1.
  • Referring to FIG. 1, a block flange generally designated 1 according to the invention is welded into a reactor wall 2. The block flange has a certain cylindrical extent and has a passage aperture 3, for example for a measuring instrument, a probe or the like.
  • In its inward-pointing area, designated 2 a in FIG. 2, the flange inner surface 4 is beveled, the bevel being designated 5 in FIG. 1. This beveled surface 5 begins approximately at the center horizontal line 6 of the flange 1, extends as far ae the horizontal center, designated 7, of the flange and from there onward to the vertical center 6, so that a form of slide results. Material falling thereon is automatically rejected as a result of gravity.
  • FIG. 2 shows a manhole design, and here again a corresponding flange design is shown, the manhole hoeing closed by a cover designated in this case 8.
  • FIG. 3 shows a block flange 1 of this type in section.
  • The examples of embodiment of the invention described can of course be modified in a great many respects without departing from the basic concept. Thus, the flange 1 or 1 a can, in particular, be welded in flush with the inner wall surface of the reactor wall 2, the flange or flange bore 3 can be arranged at a slightly downward-pointing angle to assist the sliding-off of material falling thereon, and so on.
  • The invention relates to an apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors for the oxychlorination of ethylene, oxygen and HCl, having a wall flange fixed in the reactor wall.
  • In what is known as oxychlorination, ethylene, oxygen and HCl are reacted in a fluidized bed reactor (oxyreactor) over a copper-containing catalyst to give 1,2-dichloroethane and water. In operation, and when the plant is shut down, catalyst deposits may occur in any dead spaces within the reactor. The presence of HCl results in the formation of hydrochloric acid when the temperature falls below the dew point, and hence causes severe corrosion. Particularly at risk here are dead spaces in the shell region, such as any manholes and measuring ports. Attempts have been made to remedy this disadvantage by, for example, providing heated flushing lines at all measuring ports, in order also to prevent adverse effects on measurements and temperatures falling below the dew point.
  • With manhole designs, it is known to equip the lids of said manholes internally with an additional displacement body which is so designed ms to produce the smoothest possible flush transition to the inner surface of the reactor shell.
  • It is an object of the invention to provide a solution whereby all other auxiliary measures can be dispensed with and the expense associated therewith can be eliminated without the functionality of the system suffering as a result and without undesirable deposits being formed in these areas.
  • This object is achieved, according to the invention, with an apparatus of the type described initially in that the flange surface pointing inward and downward in the direction of gravity is of beveled design, at least in some areas.
  • The invention entails a number of advantages, for example in that possible dead spaces in which catalyst deposits may be formed are reduced and all heated flushing lines that are employed in the conventional solutions, with filter stations, flowmeters, condensate collectors, mountings and the like, are eliminated.
  • In an embodiment, it is envisaged that the surface bevel is so great, at least in its area that is lowest in the direction of gravity, that deposition of catalyst granules or the like is prevented.
  • It is particularly advantageous if, as the invention likewise envisages, the bevel of the surface is designed to increase, beginning from the horizontal median plane in the inner edge region toward the vertical center of the the flange ring.
  • With this design, a smooth, homogeneous, funnel-like slide is formed, directed toward the interior of the reactor, so that for example, when the reactor is switched off and the fluidized bed sins, the deposition of catalyst material or the like is reliably prevented.
  • Further features, details and advantages of the invention are apparent from the description that follows and from reference to the drawing, in which:
  • FIG. 1 shows a simplified perspective view of a block flange according to the invention,
  • FIG. 2 shows a simplified sectional view of a manhole, and
  • FIG. 3 shows a simplified sectional view of a block flange approximately in accordance with FIG. 1.
  • Referring to FIG. 1, a block flange generally designated A) 1 according to the invention is welded into a reactor wall 2. The block flange has a certain cylindrical extent and has a passage aperture 3, for example for a measuring instrument, a probe or the like.
  • In its inward-pointing area, designated 2 a in FIG. 2, the flange inner surface 4 is beveled, the bevel being designated 5 in FIG. 1. This beveled surface 5 begins approximately at the center horizontal line 6 of the flange 1, extends as far as the horizontal center, designated 7, of the flange and from there onward to the vertical center 6, so that a form of slide results. Material falling thereon is automatically rejected as a result of gravity.
  • FIG. 2 shows a manhole design, and here again a corresponding flange design is shown, the manhole being closed bat a cover designated in this case 8.
  • FIG. 3 shows a block flange 1 of this type in section.
  • The examples of embodiment of the invention described can of course be modified in a great many respects without departing from the basic concept. Thus, the flange 1 or 1 a can, in particular, be welded in flush with the inner wall surface of the reactor wall 2, the flange or flange bore 3 can be arranged at a slightly downward-pointing Q angle to assist the sliding-off of material falling thereon, and so on.

Claims (3)

1. An apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors for the oxychlorination of ethylene, oxygen and HCl, having a wall flange fixed in the reactor wall, wherein the flange surface (5) pointing inward and downward in the direction of gravity is of beveled design, at least in some areas.
2. The apparatus as claimed in claim 1, wherein the bevel of the surface (5) is so great, at least in its area that is lowest in the direction of gravity, that deposition of catalyst granules or the like is prevented.
3. The apparatus as claimed in claim 1 or 2, wherein the bevel of the surface (S) is designed to increase, beginning from the horizontal median plane (6) in the inner edge region toward the vertical center (7) of the flange ring.
US09/849,678 1998-11-07 2005-03-15 Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors Abandoned US20060024214A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19851423A DE19851423A1 (en) 1998-11-07 1998-11-07 Device for providing a block flange of a manhole opening or the like, in particular in the case of fluidized bed reactors
DE19851423.9 1998-11-07
PCT/EP1999/008001 WO2000027517A1 (en) 1998-11-07 1999-10-21 Device for providing a loose flange of a manhole opening or the like, especially for fluidized reactors

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1999/008001 Continuation WO2000027517A1 (en) 1998-11-07 1999-10-21 Device for providing a loose flange of a manhole opening or the like, especially for fluidized reactors

Publications (1)

Publication Number Publication Date
US20060024214A1 true US20060024214A1 (en) 2006-02-02

Family

ID=7887048

Family Applications (2)

Application Number Title Priority Date Filing Date
US10/976,287 Expired - Lifetime US7285249B2 (en) 1998-11-07 2004-10-27 Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors
US09/849,678 Abandoned US20060024214A1 (en) 1998-11-07 2005-03-15 Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US10/976,287 Expired - Lifetime US7285249B2 (en) 1998-11-07 2004-10-27 Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors

Country Status (8)

Country Link
US (2) US7285249B2 (en)
EP (1) EP1135203B1 (en)
JP (1) JP4632542B2 (en)
AT (1) ATE218393T1 (en)
AU (1) AU1042400A (en)
DE (2) DE19851423A1 (en)
NO (1) NO321312B1 (en)
WO (1) WO2000027517A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6372086B2 (en) * 2014-01-28 2018-08-15 三菱ケミカル株式会社 Fluidized bed reactor and method for producing nitrile compound using the same
JP6486015B2 (en) * 2014-04-25 2019-03-20 三菱ケミカル株式会社 Fluidized bed reactor
JP2019126759A (en) * 2018-01-23 2019-08-01 旭化成株式会社 Connection structure and fluid layer reaction device
DE102018003340A1 (en) * 2018-04-24 2019-10-24 Linde Aktiengesellschaft Prevention of corrosion damage to isothermal reactors

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4203686A (en) * 1978-07-17 1980-05-20 Bowman Harold M Manhole construction
US4411877A (en) * 1979-09-14 1983-10-25 Imperial Chemical Industries Plc Synthesis processes

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4074691A (en) * 1976-07-01 1978-02-21 Exxon Research & Engineering Co. Open shroud trickle valve
ES468300A1 (en) * 1977-04-28 1978-11-16 Hoechst Ag Production of 1,2-dichloroethane
AT400368B (en) * 1991-12-09 1995-12-27 Huemer E Unistrap Verpackung METERING METHOD AND DEVICE FOR IMPLEMENTING IT

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4203686A (en) * 1978-07-17 1980-05-20 Bowman Harold M Manhole construction
US4411877A (en) * 1979-09-14 1983-10-25 Imperial Chemical Industries Plc Synthesis processes

Also Published As

Publication number Publication date
JP4632542B2 (en) 2011-02-16
US20050058580A1 (en) 2005-03-17
AU1042400A (en) 2000-05-29
US7285249B2 (en) 2007-10-23
NO20012225L (en) 2001-05-04
NO321312B1 (en) 2006-04-24
NO20012225D0 (en) 2001-05-04
DE59901678D1 (en) 2002-07-11
WO2000027517A1 (en) 2000-05-18
ATE218393T1 (en) 2002-06-15
DE19851423A1 (en) 2000-05-11
JP2002529222A (en) 2002-09-10
EP1135203A1 (en) 2001-09-26
EP1135203B1 (en) 2002-06-05

Similar Documents

Publication Publication Date Title
US20060024214A1 (en) Apparatus for the provision of a block flange of a manhole aperture or the like, in particular for fluidized bed reactors
KR970707353A (en) Water Conservation Method and Apparatus Therefor
US6986226B2 (en) Manhole water seal-cap/diverter
AU710604B2 (en) Offset connector
JP2002529222A5 (en)
US6216733B1 (en) Apparatus for the distribution of water or other liquids
EP1076135B1 (en) Cascade bath spout apparatus
US4772360A (en) Thin wall coke quenching container
CN208984195U (en) A kind of waterproof truck scale
JPH09111972A (en) Structure of gutter
ATE530097T1 (en) TOILET WITH BACKWARDS TILT SPOUT
CN221349133U (en) Boiler drum water level control device
US11512803B2 (en) Circular catch basin
SE500116C2 (en) Device for downpipes
JP2022128208A (en) Receiving frame of lid body for manhole
EP0213777B1 (en) Branch members for soil and waste systems
CN208943532U (en) A kind of sedimentation device
JP2786847B2 (en) Masu for slope road
Strommen COMPUTERMODELING AND IN-SITU CURRENT DENSITY MEASUREMENTS PROVE A NEED FOR REVISION OF OFFSHORE CP DESIGN CRITERIA
US576184A (en) Ltjdwig brandis
US170660A (en) Improvement in sewer-basins
JPH02308026A (en) Drain piping with piping unit
AU1553102A (en) Water tanks
KR20230092301A (en) Well block to prevent slag entrainment
FI73281B (en) KOMBINERAD VATTENLAOS FOER LAVOAR OCH TVAETTMASKIN.

Legal Events

Date Code Title Description
AS Assignment

Owner name: KRUPP UHDE GMBH, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SCHON, HARTMUT;REEL/FRAME:011789/0504

Effective date: 20010424

AS Assignment

Owner name: UHDE GMBH, GERMANY

Free format text: CHANGE OF NAME;ASSIGNOR:KRUPP UHDE GMBH;REEL/FRAME:014090/0526

Effective date: 20020517

STCB Information on status: application discontinuation

Free format text: EXPRESSLY ABANDONED -- DURING EXAMINATION