EP0645583A1 - Brûleur à gaz - Google Patents

Brûleur à gaz Download PDF

Info

Publication number
EP0645583A1
EP0645583A1 EP93115237A EP93115237A EP0645583A1 EP 0645583 A1 EP0645583 A1 EP 0645583A1 EP 93115237 A EP93115237 A EP 93115237A EP 93115237 A EP93115237 A EP 93115237A EP 0645583 A1 EP0645583 A1 EP 0645583A1
Authority
EP
European Patent Office
Prior art keywords
burner head
combustion air
supply pipe
fuel gas
burner
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.)
Withdrawn
Application number
EP93115237A
Other languages
German (de)
English (en)
Inventor
Hans-Benno Ricke
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.)
KRAFT-INDUSTRIEWARMETECHNIK DR RICKE GmbH
Original Assignee
KRAFT-INDUSTRIEWARMETECHNIK DR RICKE 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
Application filed by KRAFT-INDUSTRIEWARMETECHNIK DR RICKE GmbH filed Critical KRAFT-INDUSTRIEWARMETECHNIK DR RICKE GmbH
Priority to EP93115237A priority Critical patent/EP0645583A1/fr
Priority to CN 93119363 priority patent/CN1100790A/zh
Publication of EP0645583A1 publication Critical patent/EP0645583A1/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/20—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone
    • F23D14/22—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone with separate air and gas feed ducts, e.g. with ducts running parallel or crossing each other
    • F23D14/24—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone with separate air and gas feed ducts, e.g. with ducts running parallel or crossing each other at least one of the fluids being submitted to a swirling motion

Definitions

  • the invention relates to a gas burner with a burner head for merging a fuel gas and a combustion air stream, a fuel gas supply pipe, by means of which fuel gas can be guided to the burner head, and a combustion air supply pipe, by means of which combustion air can be guided to the burner head and which is coaxial with the formation of an annular space with a radial distance is arranged to the fuel gas supply pipe.
  • the invention has for its object to provide a gas burner of the type mentioned, which is suitable for a higher range of throughputs of combustion air and fuel gas on the one hand and on the other hand for every throughput quantity even combustion with high efficiency without thermal overloads of burner components or surrounding furnace area guaranteed.
  • outlet openings are formed in an inner central part of the burner head connected to the end of the combustion gas or combustion air supply pipe on the burner head side, through which the fuel gas or combustion air flow can be radiated into a burner head ring space which is between the end of the combustion air or combustion gas supply pipe on the burner head side and the outlet surface of the burner head extends essentially in the axial direction of the combustion gas or combustion air supply pipe and in its area assigned to the outlet openings of the inner central part of the burner head, the area essentially in the axial direction of the combustion gas or combustion air supply pipe Combustion air or fuel gas flow flowing through the burner head ring space with that from the outlet openings of the inner central part of the burner head escaping fuel gas or combustion air flow can be acted upon.
  • the fuel gas and the combustion air are fed coaxially to the burner head, mixed intensively within the burner head by mutual penetration, ignited and deflected together in a radial outflow direction as rotationally symmetrically as possible.
  • the entire opening cross-sectional area of the inner central part of the burner head is formed by the outlet openings opening into the burner head ring space.
  • the combustion air supply pipe has a larger diameter than the fuel gas supply pipe, so that the combustion air supply pipe coaxially surrounds the fuel gas supply pipe, with the result that the annular space is formed between the inner peripheral surface of the combustion air supply pipe and the outer peripheral surface of the fuel gas supply pipe, the end of the burner head of the fuel gas supply pipe is connected to the inner central part of the burner head, from which central part the fuel gas flow can be emitted through the outlet openings into the burner head ring space, which extends between the end of the combustion air supply pipe on the burner head side and the outlet surface of the burner head essentially in the axial direction of the fuel gas supply pipe and in the Outlet openings of the inner central part of the burner head assigned to the area essentially in the axial direction of the fuel gas feed pipe combustion air flow flowing into the burner head ring space can be acted upon by the fuel gas stream emerging from the outlet openings of the inner central part of the burner head.
  • the fuel gas jets emerging from the outlet openings of the inner central part of the burner head are expanded and carried along by the combustion air stream flowing radially outward of the inner central part of the burner head.
  • the radiation nuclei of the fuel gas jets emerging from the outlet openings strike the outer boundary of the torch head ring space, they are ultimately resolved at this outer boundary. Due to the sequence described above, the fuel gas / combustion air mixture is homogenized over a very short axial distance. Only at very low throughputs does the flame spread out according to the number of outlet openings in the inner central part of the burner head. This means that a wide range of throughputs can be used to achieve homogeneous flame formation and thus even combustion with high efficiency.
  • the burner head according to the invention can be constructed in a structurally simple manner if the burner head ring space is delimited to the outside by means of an outer envelope part of the burner head, which extends between the end of the combustion air or fuel gas supply pipe on the burner head side and the outlet surface of the burner head.
  • end section of the burner head ring space on the exit surface side is continuous, preferably progressive, enlarged, which is advantageously realized constructively by the fact that the inner circumference of the outer envelope part of the burner head in the outlet-side end section of the burner head ring space expands steadily or progressively, is achieved solely by the shape of the burner head or its outer envelope part that the mixed A thin layer of fuel gas / combustion air flow clings to the contour of the inner circumferential surface of the outer envelope part of the burner head without detachment.
  • the radial, quasi-disc-shaped design of the outflow away from the main axis of the burner or the burner head results before the latter in the area near the main axis, a zone of static vacuum into which gas from the surrounding area can flow back.
  • This gas is a backflowing, highly heated flame gas from the ongoing combustion, so that this backflow intensifies the mixing and increase in temperature of the fuel gas / combustion air flow, resulting in an increase in the ignitability of the fuel gas / combustion air flow even if the Flow velocities and thus the throughput quantities are small and as a result the mixing energy is low.
  • a further improvement in the mixing between the fuel gas and the combustion air flow and a reduction in the space required for the actual mixing results if the outlet openings of the fuel gas or combustion air supply pipe run radially to the main axis of the fuel gas or combustion air supply pipe.
  • the outlet surface of the gas burner described above is arranged approximately flush with a furnace wall or ceiling, each of which forms a plane extending in the radial direction and consists of a heat-resistant material, the flame remains stable during operation of the gas burner and nestles against the inner one Surfaces of the furnace wall or ceiling until the flame has released its flow energy to the surrounding medium.
  • the burner head is surrounded by a cladding tube made of a heat-resistant material and coaxial with it, the flat flame gas jet flowing out of the outlet surface of the burner head is redirected in the axial direction by the inner wall of the cladding tube. Due to the inflow into the space near the main axis in front of the burner head, a toroidal ring vortex is formed, which leads to the intensified mixing and combustion described above contributes.
  • the cladding tube has a narrowed outlet cross section and bores upstream of the outlet-side end section of the burner head ring space, an annular gap being formed between the inner peripheral surface of the cladding tube and the outer peripheral surface of the burner head, part of the flame gas is discharged through the annular gap and these bores counter to the main flow direction.
  • the combustion air supply pipe upstream of the burner head has bores through which combustion air can be introduced into the space between the outer peripheral surface of the combustion air supply pipe or the burner head and the inner peripheral surface of the cladding tube; an external secondary cladding tube with a progressively widening outlet section is provided for carrying out a secondary combustion.
  • a two-stage combustion can be implemented, which may be desirable in the exhaust gas for reasons of the increasingly frequent nitrogen oxide reduction.
  • the radial outflow along the outlet surface of the burner head also forms when both the fuel gas and the combustion air stream are swirl-free.
  • a characteristic angular momentum of the flame being formed, which is characteristic of flat flame burners, is not necessary in the gas burner described above. Even a targeted rectification of the fuel gas and combustion air flow and also laminar flow conditions do not change the radial outflow profile achieved in the invention.
  • the cladding tube quasi as the outer wall of a combustion chamber or as a combustion chamber cladding wall acts.
  • the width of the burner head gap formed between the conical ring shoulder and the envelope surface of the outer envelope part of the burner head can be changed by axially displacing the inner central part to set desired flow conditions.
  • outlet openings of the inner central part of the burner head are arranged immediately downstream of the radial end face of the conical ring attachment forming the tear-off edge of the combustion air or fuel gas stream, the outlet conditions from these outlet openings are largely independent of the combustion air or fuel gas stream flowing past the outlet openings. Accordingly, an ejection effect is avoided.
  • the outer envelope part of the burner head is advantageously formed at its input end with an introduction element, the inner circumferential edge of which acts as a centering element is designed for the inner central part of the burner head.
  • a burner head 1 of a gas burner according to the invention shown in FIGS. 1 and 2 essentially consists of an inner central part 2 and an outer envelope part 3.
  • a burner head ring space 5 is formed between an inner circumferential or enveloping surface 4 of the outer enveloping part 3 of the burner head 1 and an outer circumferential surface of the essentially cylindrical inner part 2.
  • the inner central part 2 of the burner head 1 is as from 3 and 4 shows connected to a fuel gas supply pipe 6 through which the burner head 1 or the inner central part 2 is supplied with fuel gas.
  • the burner head ring space 5 formed between the inner central part 2 and the outer envelope part 3 of the burner head 1 is connected to a combustion air supply pipe 7 on the input side, as can be seen from FIGS. 3 and 4.
  • the combustion air supply pipe 7 is arranged concentrically to the fuel gas supply pipe 6 at a radial distance, so that an annular space 8 is formed between the outer peripheral surface of the fuel gas supply pipe 6 and the inner peripheral surface of the combustion air supply pipe 7, into which combustion air flows from a connecting pipe 9 and from the combustion air into between the inner Central part 2 and the outer envelope part 3 of the burner head 1 flows formed burner head ring space 5.
  • the outer envelope part 3 of the burner head 1 is provided with an introduction element 10.
  • the introduction element 10 forms an annular entry space 11 which is delimited on the inside by the outer circumferential surface of an inner circumferential ring 12, the inner circumferential surface of which is cylindrical and bears on the outer circumferential surface of the inner central part 2.
  • the cylindrical inner peripheral surface of the inner peripheral ring 12 of the introduction element 10 serves to center the inner central part 2 with respect to the outer envelope part 3 of the burner head. This centering achieves a uniform, rotationally symmetrical design of the burner head ring space 5, which is necessary to maintain homogeneous and uniform flow conditions within the burner head 1.
  • the inner central part 2 which is arranged symmetrically to the main axis 13 of the burner head 1 or the gas burner, is designed near an outlet surface or outlet plane 14 of the burner head 1 with outlet openings 15 running radially to the main axis 13, which are arranged in the outlet surface sides arranged near the outlet surface 14 of the burner head 1 Open end section 16 of torch head ring chamber 5.
  • the inner central part 2 On its end face parallel to the exit face or exit plane 14 of the burner head 1, the inner central part 2 is closed, so that the entire fuel gas flow flowing through the inner central part 2 is radiated through the exit openings 15 into the end face 16 of the burner head ring space 5 on the exit face side.
  • the radiation takes place orthogonally or radially to the main axis 13 of the burner head 1 or the gas burner and to the main flow direction of the combustion air flow through the burner head ring space 5.
  • a conical ring extension 17 is formed on the outer peripheral surface of the inner central part 2, the radial end surface 18 of which faces the outlet openings 15.
  • the free edge of the radial end surface 18 of the conical ring extension 17 forms a tear-off edge 19, by means of which the combustion air flow flowing through the burner head ring space 5 is released from the outer peripheral surface of the inner central part 2. This effect prevents the flow conditions at the outlet surfaces of the outlet openings 15 of the inner central part 2 from being adversely affected by any ejection effects.
  • the burner head ring space 5 Downstream of the introduction element 10, the burner head ring space 5 initially narrows until it reaches its narrowest point and thus the burner head gap 20 in the region of the conical ring shoulder 17 of the inner central part 2.
  • the narrowing of the cross section of the burner head ring space 5 results from a gradual decrease in the inner diameter of the outer envelope part 3 of the burner head 1.
  • the inner circumference of the outer envelope part 3 of the burner head 1 expands progressively, so that in the outlet surface-side end section 16 of the burner head ring space 5 there is the outer envelope surface 4, against which the combustion air flow or the mixed combustion gas / combustion air flow clings due to the Coanda effect.
  • the progressive enlargement of the inner diameter of the outer cooling part 3, which is decisive for the corresponding design of the envelope surface 4, is selected such that the fuel gas / combustion air flow exiting through the outlet surface 14 of the burner head 1 is virtually radial with respect to the main axis 13 of the burner head 1 flows.
  • a key engagement 21 is formed on the end wall side of the inner central part 2 on the exit surface side, the actuation of which can cause an axial displacement of the inner central part 2 in relation to the outer envelope part 3 of the burner head 1.
  • the axial displacement of the inner central part 2 can thus adjust the width of the burner head gap 20.
  • the burner head 1 can thus be adapted to different throughput quantities of fuel gas or combustion air, the most favorable flow conditions being adjustable in a simple manner for different throughput quantities.
  • FIG 3 shows the burner head 1 described above shown in cooperation with a cladding tube 22.
  • the cladding tube is arranged concentrically with the burner head 1, an annular gap 23 being formed between the inner circumferential surface of the cladding tube 22 and the circumferential surface of the outer cladding part 3 of the burner head 1 on the exit surface side.
  • annular gap 23 flame gases can flow from the actual combustion chamber 24 formed downstream of the outlet surface 14 of the burner head 1 inside the cladding tube 22 into an intermediate space 25 formed between the outer circumferential surface of the combustion air supply pipe 7 or the outer cladding part 3 of the burner head 1 and the inner circumferential surface of the cladding tube 22 flow in.
  • This effect is reinforced by the fact that the cladding tube 22 is designed with a narrowed outlet cross section in the region of its outlet surface 26 arranged downstream of the burner head 1.
  • the cladding tube 22 is configured with bores 27 through which hot flame gases emerge from the intermediate space 25. This prevents thermal stresses from occurring in the cladding tube 22 in the region of the burner head 1 due to excessive temperature differences.
  • recesses 29 are formed on the outer circumferential surface of the section of the outer envelope part 3 of the burner head 1 forming the exit surface-side end section 16 of the burner head ring chamber 5.
  • the flame gas flow flowing off in the radial direction along the exit plane 14 of the burner head 1 is again subjected to an axial component by the inner wall of the cladding tube 22, due to which the penetration of flame gases into the space near the main axis in which because of the radial outflow of the flame gases there is negative pressure, is supported. This results in the particularly favorable mixing, ignition and combustion conditions already mentioned.
  • the gas burner is arranged within a furnace wall opening 30 of a furnace wall 31 in such a way that its outlet surface or plane 14 is approximately at the inner surface the furnace wall 31 is aligned.
  • the radial outflow of the flame gases nestles against the inside of the furnace wall 31, parts of the flame gases being sucked into the area near the main axis 13 due to the negative pressure prevailing in the region of the main axis 13 of the burner head 1. This results in the particularly favorable mixing, ignition and combustion ratios already mentioned above.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Pre-Mixing And Non-Premixing Gas Burner (AREA)
EP93115237A 1993-09-22 1993-09-22 Brûleur à gaz Withdrawn EP0645583A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP93115237A EP0645583A1 (fr) 1993-09-22 1993-09-22 Brûleur à gaz
CN 93119363 CN1100790A (zh) 1993-09-22 1993-11-12 气化喷燃器

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP93115237A EP0645583A1 (fr) 1993-09-22 1993-09-22 Brûleur à gaz

Publications (1)

Publication Number Publication Date
EP0645583A1 true EP0645583A1 (fr) 1995-03-29

Family

ID=8213289

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93115237A Withdrawn EP0645583A1 (fr) 1993-09-22 1993-09-22 Brûleur à gaz

Country Status (2)

Country Link
EP (1) EP0645583A1 (fr)
CN (1) CN1100790A (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0875719A1 (fr) * 1997-05-01 1998-11-04 Haldor Topsoe A/S Brûleur tourbillonneteur
WO2001084050A1 (fr) * 2000-04-30 2001-11-08 Casale Chemicals S.A. Bruleur
WO2012104012A1 (fr) * 2011-02-04 2012-08-09 Vdeh-Betriebsforschungsinstitut Gmbh Brûleur à flamme plate
WO2019097483A1 (fr) * 2017-11-20 2019-05-23 John Zink Company, Llc Brûleur mural radiant

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102588995B (zh) * 2011-01-11 2014-04-09 陈喜春 快速喷射气化器
CN104613473B (zh) * 2015-01-30 2017-11-10 中国东方电气集团有限公司 一种多孔燃气射流烧嘴
CN105509052B (zh) * 2015-11-30 2018-11-09 江苏大学 一种带弧形体射流装置的烧嘴
CN106765096B (zh) * 2016-12-30 2024-01-02 上海泽玛克敏达机械设备有限公司 气化炉引导烧嘴
CN108443877A (zh) * 2018-05-03 2018-08-24 广东美的厨房电器制造有限公司 燃烧器和燃气灶具
CN110513680B (zh) * 2018-05-21 2024-02-23 安德森热能科技（苏州）有限责任公司 一种低NOx燃气燃烧器及其火焰调节方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1340902A (en) * 1918-07-31 1920-05-25 Lundgaard Ivar Gas-burner
US1600516A (en) * 1926-02-13 1926-09-21 Alexander H Shaw Fuel burner
US2855033A (en) * 1955-10-03 1958-10-07 Selas Corp Of America Industrial gas burner
US4077761A (en) * 1976-08-04 1978-03-07 Sid Richardson Carbon & Gasoline Co. Carbon black reactor with axial flow burner
EP0003900A2 (fr) * 1978-02-27 1979-09-05 John Zink Company Brûleur à gaz avec une flamme collante à la surface de la brique
EP0031206A1 (fr) * 1979-12-05 1981-07-01 Nu-Way Energy Limited Brûleur à gaz pour le chauffage d'air
DE4001378A1 (de) * 1990-01-18 1991-07-25 Kraft Industriewaermetechnik D Brenner mit niedriger nox-emission
EP0483520A2 (fr) * 1990-10-02 1992-05-06 VAW Aluminium AG Procédé et dispositif pour la combustion des combustibles gazeux et liquided avec génération réduite des substances nocives

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1340902A (en) * 1918-07-31 1920-05-25 Lundgaard Ivar Gas-burner
US1600516A (en) * 1926-02-13 1926-09-21 Alexander H Shaw Fuel burner
US2855033A (en) * 1955-10-03 1958-10-07 Selas Corp Of America Industrial gas burner
US4077761A (en) * 1976-08-04 1978-03-07 Sid Richardson Carbon & Gasoline Co. Carbon black reactor with axial flow burner
EP0003900A2 (fr) * 1978-02-27 1979-09-05 John Zink Company Brûleur à gaz avec une flamme collante à la surface de la brique
EP0031206A1 (fr) * 1979-12-05 1981-07-01 Nu-Way Energy Limited Brûleur à gaz pour le chauffage d'air
DE4001378A1 (de) * 1990-01-18 1991-07-25 Kraft Industriewaermetechnik D Brenner mit niedriger nox-emission
EP0483520A2 (fr) * 1990-10-02 1992-05-06 VAW Aluminium AG Procédé et dispositif pour la combustion des combustibles gazeux et liquided avec génération réduite des substances nocives

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0875719A1 (fr) * 1997-05-01 1998-11-04 Haldor Topsoe A/S Brûleur tourbillonneteur
WO2001084050A1 (fr) * 2000-04-30 2001-11-08 Casale Chemicals S.A. Bruleur
AU782073B2 (en) * 2000-04-30 2005-06-30 Casale Chemicals S.A. Burner
WO2012104012A1 (fr) * 2011-02-04 2012-08-09 Vdeh-Betriebsforschungsinstitut Gmbh Brûleur à flamme plate
WO2012119675A1 (fr) * 2011-02-04 2012-09-13 Vdeh-Betriebsforschungsinstitut Gmbh Brûleur à flamme plate
WO2019097483A1 (fr) * 2017-11-20 2019-05-23 John Zink Company, Llc Brûleur mural radiant
RU2768639C2 (ru) * 2017-11-20 2022-03-24 Джон Цинк Компани, ЛЛК Радиационная стеновая горелка
US11585529B2 (en) * 2017-11-20 2023-02-21 John Zink Company, Llc Radiant wall burner

Also Published As

Publication number Publication date
CN1100790A (zh) 1995-03-29

Similar Documents

Publication Publication Date Title
EP0193838B1 (fr) Disposition de brûleur pour installations de combustion, en particulier pour chambres de combustion d'installations de turbines à gaz ainsi que procédé de sa mise en oeuvre
EP0438682B1 (fr) Système d'échappement avec filtre à particules et brûleur de régénération
DE10217913B4 (de) Gasturbine mit Brennkammer zur flammenlosen Oxidation
DE3027587C2 (fr)
DE2131490C2 (de) Brenner-Mischdüse
EP1802915B1 (fr) Bruleur pour turbine a gaz
DE3113381C2 (fr)
CH680014A5 (fr)
DE2839703A1 (de) Ringfoermiger doppelbrenner
DE4326802A1 (de) Brennstofflanze für flüssige und/oder gasförmige Brennstoffe sowie Verfahren zu deren Betrieb
WO1999037951A1 (fr) Dispositif permettant de supprimer les oscillations de la flamme/pression dans un foyer, notamment une turbine a gaz
EP0724114A2 (fr) Brûleur
EP0401529A1 (fr) Chambre de combustion d'une turbine à gaz
WO1999004196A1 (fr) Agencement de bruleurs pour une installation de chauffe, notamment une chambre de combustion de turbine a gaz
EP0718550B1 (fr) Gicleur
EP0645583A1 (fr) Brûleur à gaz
DE2261596B2 (de) Verfahren und Brennkammer zum Verbrennen eines Brennstoffes
EP0101462B1 (fr) Bruleur pour carburants a l'etat poudreux, gazeux et/ou liquide
EP0742411A2 (fr) Alimentation en air pour une chambre de combustion à prémélange
EP0714001A2 (fr) Chambre de combustion avec brûleurs de prémélange
DE2226939A1 (de) Brenner
EP0483554A1 (fr) Procédé pour la réduction au minimum des émissions de NOx dans une combustion
DE3923238C2 (de) Einrichtung zum Rückführen von Verbrennungsprodukten
EP0777082A2 (fr) Brûleur à prémélange
DE1501970A1 (de) Brenner fuer OEfen

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT PT

17P Request for examination filed

Effective date: 19950919

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19970402