EP0808417A1 - Procede et un dispositif d'epuration de l'air d'admission d'une turbine a gaz - Google Patents
Procede et un dispositif d'epuration de l'air d'admission d'une turbine a gazInfo
- Publication number
- EP0808417A1 EP0808417A1 EP96900619A EP96900619A EP0808417A1 EP 0808417 A1 EP0808417 A1 EP 0808417A1 EP 96900619 A EP96900619 A EP 96900619A EP 96900619 A EP96900619 A EP 96900619A EP 0808417 A1 EP0808417 A1 EP 0808417A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- air
- filter
- arrangement
- electrostatic
- mechanical
- 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- Withdrawn
Links
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000004140 cleaning Methods 0.000 title claims abstract description 15
- 238000001914 filtration Methods 0.000 claims abstract description 46
- 239000000835 fiber Substances 0.000 claims description 26
- 238000000926 separation method Methods 0.000 claims description 10
- 239000012717 electrostatic precipitator Substances 0.000 claims description 9
- 238000009413 insulation Methods 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 4
- 238000010248 power generation Methods 0.000 claims description 4
- 230000008014 freezing Effects 0.000 claims description 2
- 238000007710 freezing Methods 0.000 claims description 2
- 230000003750 conditioning effect Effects 0.000 claims 2
- 239000002245 particle Substances 0.000 abstract description 28
- 239000004744 fabric Substances 0.000 abstract description 6
- 230000000295 complement effect Effects 0.000 abstract 1
- 230000005684 electric field Effects 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000005367 electrostatic precipitation Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000012716 precipitator Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 235000003197 Byrsonima crassifolia Nutrition 0.000 description 1
- 240000001546 Byrsonima crassifolia Species 0.000 description 1
- 235000008694 Humulus lupulus Nutrition 0.000 description 1
- 244000025221 Humulus lupulus Species 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000011045 prefiltration Methods 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
- B03C3/017—Combinations of electrostatic separation with other processes, not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D50/00—Combinations of methods or devices for separating particles from gases or vapours
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
- F02C7/04—Air intakes for gas-turbine plants or jet-propulsion plants
- F02C7/05—Air intakes for gas-turbine plants or jet-propulsion plants having provisions for obviating the penetration of damaging objects or particles
- F02C7/052—Air intakes for gas-turbine plants or jet-propulsion plants having provisions for obviating the penetration of damaging objects or particles with dust-separation devices
Definitions
- the present invention relates to a method according to the preamble of claim 1 for cleaning the intake air to gas turbine equipment employed in electric power genera ⁇ tion.
- the method also concerns an arrangement suited for imple- menting the method.
- the intake air to the compressor section of a gas tur ⁇ bine that is, the combustion air of the turbine is cleaned with the help of mechanical fiber filters.
- the purpose of intake air filtration is to obstruct the entry of abrasive and contaminating particles into the com ⁇ pressor and the turbine, thus preventing the wear of equipment and reducing the need for cleaning and mainte ⁇ nance.
- large gas turbines employed in electric power generation also require extremely large amounts of combustion air, very small concentrations of contaminat ⁇ ing particulates result in heavy internal build-up of dirt in the equipment during running, which means that the filtration of the combustion air should be as effec- tive as possible.
- the design value of filtration efficiency will always be a compromise dictated by local circumstances.
- Such output power reduction is caused by a number of different factors including wear due to the particles, inefficiency of methods used for internal cleaning of equipment leading to gradual accu ⁇ mulation of dirt and extra wear due to such cleaning as well as increase of tolerances in seals resulting in higher leak rates. Even the smallest degradation of output power over the service life of the equipment causes significant economic losses. Also the efficiency of the turbine degrades with the internal dirt build-up, which necessitates cleaning of the compressor and the turbine at scheduled intervals. Cleaning is carried out by washing with water complemented with different kinds of crushed material. Such water wash in particular is hampered by freezing under low-temperature conditions. Extra operating costs associated with dirt build-up in equipment are traceable to increased fuel consumption, loss of output power capacity and compressor cleaning costs.
- the goal of the invention is achieved by complementing the mechanical filtration of intake air with at least one electrostatic filtering stage an a stage in which the electrical properties of particles suspended in the air are improved electrically or chemically.
- the invention offers significant benefits.
- Electrostatic precipitation methods have not been used in the prior art for cleaning large-volume air flows, because conventional filtering would have required such a high electric power to be expended for charging the suspended particles that the cost-efficiency of filtration would have been lost.
- electrostatic precipita ⁇ tion may advantageously be used, because essentially lower charging voltages can then be used in such a com ⁇ bination without compromising a good degree of separa- tion.
- the pressure losses of filtration may be reduced and mechanical filtration can be implemented using a filter of a lower degree of separation, whereby the pressure drop over the filter is smaller and the fouling rate of the filter in use is lowered, which permits less frequent replacement of the filters. Resultingly, process shutdowns and replacement costs of filters are reduced.
- the filtration arrangement may also be designed so that the system comprises a partially or entirely duplicated parallel filter system, whereby maintenance of the filtration system may be performed off-line, while the power generating system is run continuously.
- the electro- static stage achieves separation of smaller particles from the intake air than is possible with conventional filtration methods, whereby the total mass of contaminating particles passing through the filter is reduced essentially. Such improvement in filtration effi- ciency is truly significant as if a relative value of
- a relative value as good as 50 is attained by combining mechanical coarse filtration with two stages of filtration based on electrostatic methods.
- the intake air consumption of a gas turbine may easily be as high as 120 rnVs, it is obvious that the intake air flow carries along a great quantity of con ⁇ taminating particles that must be removed.
- An electrostatic precipitator is an apparatus comprising planar parallel plates connencted to a voltage source.
- One type electrostatic fiber filter is a filter comprising electrically charged fibers which have a permanent electric polarization.
- the fibers or a porous filtering media is not permanently charged but an active electric fied is used to activate the filter. All these types of apparatuses are commonly called electric filters.
- the filter arrangement shown therein comprises a mechanical fiber filter 1, an elec ⁇ trostatic precipitator 3 having corona wires 2 in the front of the unit and followed by an electrostatic fibre filter 4.
- the filter arrangement also incorporates a framework 5 to which the filter units are attached.
- the farmeworm is shown herein only diagrammatically.
- the mechanical filter 1 comprises a fiber layer, wherein the fibers may be formed to a fabric.
- the fiber layer is permeable to the air flow, and when and during the passage a portion of the suspended particles passing through the fiber layer adhere thereto.
- the mechanical filter 1 is followed by two more filtering stages, its filtering separation capability need not extend down to the smallest particles, whereby a filter 1 of lower separation capability and higher air permeability can be used.
- the function of the mechanical filter l is to separate a major portion of the total mass of contaminating particles thus protecting the subsequent filter stages.
- corona wires 2 Following the mechanical filter 1 in the filter arrange ⁇ ment are adapted corona wires 2. These wires 2 are taken to a high DC voltage so that an electric field is created around the wires.
- the purpose of the corona wires 2 is to charge the passing particles.
- the corona wires are fol ⁇ lowed by an electrostatic precipitator 3 comprising planar, parallel oriented plates disposed at a short distance from each other. Also these plates are taken to a DC high-voltage supply, whereby an electric field is created between the plates.
- such a filter When properly operated, such a filter is capable of separating at least more than 80 %, under favourable conditions even more than 90 %, of the suspended particles having a size in the range 0.1 - 1 urn. An even better degree of separation can be attained for particul- ates of larger size.
- the principal operating parameters of such a precipitator are the corona wire current, collecting current applied to the plates, and in particular, the air stream velocity which may not be so high that the adhesion of the particulates to the plates would be impaired.
- the electrostatic precipitator 3 is followed by an electrostatic fiber filter 4.
- a filter 4 is comprised of fibers which are charged so as to hold a permanent electric charge such that the fibers are polarized. Therefore, this kind of filter requires no external power supply and have an extremely simple structure.
- the electrostatic fiber filter is given a pleated form so that the mouths of the pleats are oriented to face the impinging air flow.
- the electrostatic fiber filter 4 is placed as the last filter element along the path of the air flow, because due to the relatively high price of such a filter, its replacement costs represent a substantial investment, and on the other hand, under adverse operating conditions, the efficiency of electrostatic fiber filters may be lost very rapidly.
- the optimum use of this filter type is in the separation of the smallest particulates representing a small quantity of contaminating dirt mass.
- the present invention may have alternate embodiments.
- the intake air flow is taken first through such a filter that is capable of separating the major portion of particulates from the air, thus protecting the successive filtering stages intended for separating the particulates of smaller size against damage by overload or premature clogging.
- the first filtering stage is advantageously a coarse mechanical filter or an electrostatic precipitator.
- One alternative for a filter to be used in the first or successive filtering stage is electrostatic fiber filter based on an active electric field that polarizes both the particles as well as the filter media comprised of fibers or porous material.
- Such a filter must be provided with corona wires or similar elements such as chemical means or charging plates for charging the particles suspended in the air prior to their passage toward the actual filter element.
- a cyclone separator may be combined with the arrangement according to the invention, the cyclone is arranged before the mechanical filtering stage and if some kind of electric filtration is performed before the mechanical filtration, before that stage also.
- the number of filter units and their mutual order may be varied provided that the filter arrangement comprises at least one mechanical filter and, placed after the mechanical filter, an electric filter capable of separating small suspended particles that have passed the mechanical filter. If an electric fiber filter is used, it must be located as the last unit due to its susceptibility to damage.
- the filter arrangement according to the above-described embodiment has been found the most advantageous combination in practice.
- the filter arrangement must be dimensioned so that the pressure loss over it will not exceed that of conventional filter arrangements. In most cases it is even possible to lower the pressure loss below conventional values.
- the design of the filters and the entire filter arrangement may be varied flexibly.
- An important accessory in the filter system comprises the different cleaning means of which the most important is the washing apparatus of the electrostatic precipitator. Such means makes it possible to lengthen the maintenance interval of the filter arrangement. Additional improvement to the operating reliability can be imparted by providing heater elements for heating filter insulations of the electrostatic percipitator and by partially duplicating the filter system.
- one electrostatic stage may receive air selected to pass through one of two parallel mechanical coarse filters, for instance, whereby the replacement of the mechanical filters will be easier.
- the filter system is provided with a plate-type electrostatic precipitator, the filter system achieves a high availability as the washing of the percipitator plates may be readily automated.
- the system may also comprise two parallal mechanical filters, two parallel electrostatic percipitators and one common electrostatic fiber filter.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrostatic Separation (AREA)
Abstract
L'invention porte sur un procédé et un dispositif d'épuration de l'air d'admission du compresseur d'une turbine à gaz utilisée pour la production d'énergie. On emploie usuellement des filtres mécaniques en tissu en tant que filtres à air d'admission de turbines à gaz, qui comme on le sait ne filtrent que les particules relativement grosses et laissent passer une certaine quantité de particules contaminantes en suspension dans l'air qui peuvent provoquer l'encrassement de la turbine. L'invention permet d'épurer l'air d'admission de manière nettement plus efficace à l'aide d'un procédé combinant l'étage mécanique de filtrage de l'air d'admission et un étage complémentaire servant à améliorer électriquement ou chimiquement les propriétés électriques des particules en suspension dans l'air.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI950576A FI101318B (fi) | 1995-02-09 | 1995-02-09 | Menetelmä ja sovitelma kaasuturbiinin imuilman puhdistamiseksi |
| FI950576 | 1995-02-09 | ||
| PCT/FI1996/000027 WO1996024760A1 (fr) | 1995-02-09 | 1996-01-12 | Procede et un dispositif d'epuration de l'air d'admission d'une turbine a gaz |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0808417A1 true EP0808417A1 (fr) | 1997-11-26 |
Family
ID=8542821
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP96900619A Withdrawn EP0808417A1 (fr) | 1995-02-09 | 1996-01-12 | Procede et un dispositif d'epuration de l'air d'admission d'une turbine a gaz |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0808417A1 (fr) |
| JP (1) | JPH11501096A (fr) |
| CN (1) | CN1173908A (fr) |
| AU (1) | AU4450096A (fr) |
| FI (1) | FI101318B (fr) |
| WO (1) | WO1996024760A1 (fr) |
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE602004009463T2 (de) * | 2004-12-23 | 2008-07-24 | W. L. Gore & Associates Gmbh | Luftfilter für Turbineneinlass |
| EP1769851A1 (fr) * | 2005-09-27 | 2007-04-04 | Balcke-Dürr GmbH | Filtre électrostatique |
| JP4839380B2 (ja) * | 2006-01-13 | 2011-12-21 | ゼンダー グループ ノルディック エー ビー | エアフィルタおよびかかるエアフィルタの製造方法 |
| SE530041C2 (sv) * | 2006-07-14 | 2008-02-12 | Freshman Ab | Luftfilterarrangemang och ett förfarande för tillverkning av ett sådant luftfilterarrangemang |
| NO326633B1 (no) * | 2006-12-28 | 2009-01-26 | Age Jorgen Skomsvold | Fremgangsmate og anordning for motor- og kompresjonsprosess |
| US7695551B2 (en) * | 2008-03-12 | 2010-04-13 | Bha Group, Inc. | Apparatus for filtering gas turbine inlet air |
| US7527674B1 (en) * | 2008-03-12 | 2009-05-05 | Bha Group, Inc. | Apparatus for filtering gas turbine inlet air |
| US8043413B2 (en) * | 2008-12-22 | 2011-10-25 | General Electric Company | System and method for removing a foreign object from an airstream entering a turbomachine |
| CN101915164B (zh) * | 2010-09-03 | 2012-09-05 | 中国航空动力机械研究所 | 一种燃气轮机进气粒子分离装置 |
| JP6302325B2 (ja) * | 2014-03-28 | 2018-03-28 | 三菱日立パワーシステムズ株式会社 | フィルタ管理装置及び吸気ダクト |
| US20170051670A1 (en) * | 2015-08-18 | 2017-02-23 | General Electric Company | Power system and methods of assembling the same |
| CA3005905A1 (fr) | 2015-12-02 | 2017-06-08 | Lundberg LLC | Systeme, appareils, et procedes pour ameliorer le fonctionnement d'une turbine a l'aide d'une precipitation electrostatique |
| KR102408147B1 (ko) * | 2018-11-19 | 2022-06-15 | 클레어 주식회사 | 정전기 유도 방식 공기 청정 방법 |
| US20220001393A1 (en) * | 2018-11-19 | 2022-01-06 | Clair Inc. | Electrostatic induction-type air filtration dust collecting apparatus and method |
| CN110513195A (zh) * | 2019-09-27 | 2019-11-29 | 江苏欧瑞特新材料有限公司 | 燃气轮机进气系统板式预过滤器 |
| US11578656B2 (en) | 2020-01-28 | 2023-02-14 | General Electric Company | Air filtration assemblies for gas turbine systems and methods for filtering intake air in gas turbine systems |
| US11643942B2 (en) * | 2021-07-28 | 2023-05-09 | General Electric Company | Turbine system with particulate presence and accumulation model for particulate ingress detection |
| FR3149344A1 (fr) * | 2023-06-02 | 2024-12-06 | Safran Aircraft Engines | Turbomachine pour un aeronef et ses procedes de filtration et de nettoyage |
| CN116677497B (zh) * | 2023-06-13 | 2026-03-10 | 山东大学 | 一种静电-叶片耦合除雾装置及方法 |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3617149A (en) * | 1969-10-06 | 1971-11-02 | Caterpillar Tractor Co | Air inlet filter assembly |
| US4244709A (en) * | 1979-07-13 | 1981-01-13 | Union Carbide Corporation | High intensity ionization-electrostatic precipitation system for particle removal and method of operation |
| US4251234A (en) * | 1979-09-21 | 1981-02-17 | Union Carbide Corporation | High intensity ionization-electrostatic precipitation system for particle removal |
| US4926620A (en) * | 1988-07-08 | 1990-05-22 | The Dow Chemical Company | Cleaning gas turbine inlet air |
-
1995
- 1995-02-09 FI FI950576A patent/FI101318B/fi not_active IP Right Cessation
-
1996
- 1996-01-12 WO PCT/FI1996/000027 patent/WO1996024760A1/fr not_active Ceased
- 1996-01-12 JP JP8524015A patent/JPH11501096A/ja active Pending
- 1996-01-12 AU AU44500/96A patent/AU4450096A/en not_active Abandoned
- 1996-01-12 EP EP96900619A patent/EP0808417A1/fr not_active Withdrawn
- 1996-01-12 CN CN96191843.8A patent/CN1173908A/zh active Pending
Non-Patent Citations (1)
| Title |
|---|
| See references of WO9624760A1 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1173908A (zh) | 1998-02-18 |
| AU4450096A (en) | 1996-08-27 |
| FI950576L (fi) | 1996-08-10 |
| FI950576A0 (fi) | 1995-02-09 |
| FI101318B1 (fi) | 1998-05-29 |
| FI101318B (fi) | 1998-05-29 |
| JPH11501096A (ja) | 1999-01-26 |
| WO1996024760A1 (fr) | 1996-08-15 |
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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 |
|
| 17P | Request for examination filed |
Effective date: 19970717 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE FR GB SE |
|
| 17Q | First examination report despatched |
Effective date: 19990817 |
|
| 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: 19991228 |