EP0238907A2 - Low excess air tangential firing system - Google Patents
Low excess air tangential firing system Download PDFInfo
- Publication number
- EP0238907A2 EP0238907A2 EP87103150A EP87103150A EP0238907A2 EP 0238907 A2 EP0238907 A2 EP 0238907A2 EP 87103150 A EP87103150 A EP 87103150A EP 87103150 A EP87103150 A EP 87103150A EP 0238907 A2 EP0238907 A2 EP 0238907A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- air
- furnace
- coal
- auxiliary air
- primary
- 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.)
- Granted
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C5/00—Disposition of burners with respect to the combustion chamber or to one another; Mounting of burners in combustion apparatus
- F23C5/08—Disposition of burners
- F23C5/32—Disposition of burners to obtain rotating flames, i.e. flames moving helically or spirally
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D1/00—Burners for combustion of pulverulent fuel
Definitions
- Pulverized coal has been successfully burned in suspension in furnaces by tangential firing methods for a long time.
- the technique involves introducing the coal and air into a furnace from the four corners thereof so that it is directed tangent to an imaginary circle in the center of the furnace.
- This type of firing has many advantages, among them being good mixing of the fuel and air, stable flame conditions, and long residence time of the combustion gases in the furnace. In recent times, it has become important to minimize air pollution as much as possible.
- some proposed changes have been made to the standard tangential firing method.
- One such arrangement is set forth in our pending agent application Serial No. 786,432, entitled "A Control System and Method for Operating a Tangentially Fired Pulverized Coal Furnace", filed on October 11, 1985.
- That application proposes introducing pulverized coal and air tangentially into the furnace from a number of lower burner levels in one direction, and introducing coal and air tangentially into the furnace from a number of upper burner levels in the opposite direction.
- This arrangement better mixing of the fuel and air is accomplished, thus permitting the use of less excess air than with a normal tangentially fired furnace, which generally is fired with 20-30% excess air.
- the reduction in excess air helps minimize the formation of NO x which is a major air pollutant of coal-fired furnaces. It also results in increased efficiency of the unit.
- the above firing technique reduces NO x , it does have some disadvantages.
- a furnace in which pulverized coal in burned in suspension with good mixing of the coal and air, as is the case of the above-mentioned patent application.
- all of the advantages previously associated with tangentially fired furnaces are obtained, by having a swirling, rotating, fire ball in the furnace.
- the walls are protected by a blanket of air, reducing slagging thereof. This is accomplished by introducing coal and primary air into the furnace tangentially at a first level, introducing auxiliary air in an amount at least twice that of the primary air into the furnace tangentially at a second level directly above the first level, but in a direction opposite to that of the primary air, with there being a plurality of such first and second levels, one above the other.
- the ultimate swirl within the furnace will be in the direction of the auxiliary air introduction. Because of this, the fuel, which is introduced in a direction counter to the swirl of the furnace, is forced after entering the unit, to change direction to that of the overall furnace gases. Tremendous turbulent mixing between the fuel and air is thus created in this process. This increased mixing reduces the need for high levels of excess air within the furnace. This increased mixing also results in enhanced carbon conversion which improves the units over all heat release rate while at the same time reducing upper furnace slagging and fouling.
- the auxiliary air is directed at a circle of larger diameter than that of the fuel, thus forming a layer of air adjacent the walls.
- overfire air consisting essentially of all of the excess air supplied to the furnace, is introduced into the furnace at a level considerably above all of the primary and auxiliary air introduction levels, with the overfire air being directed tangentially to an imaginary circle, and in a direction opposite to that of the auxiliary air.
- a coal-fired furnace 10 having a plurality of levels of burners 12 therein with each level having a burner mounted in each of the four corners thereof. Air is supplied to the burners from fan 16 through ducts 18 and 20. Air is also supplied to pulverizer 22 through duct 24. Pulverized coal is transported to the burners in an air stream through ducts 26 and 28. There are separate air and fuel ducts leading to each individual burner, with separate valves and controls (not shown) also, so that each burner can be independently controlled. The combustion gases swirling upwardly in the furnace give up heat to the fluid passing through the tubes 30 lining all four of the furnace walls, before exiting the furnace through horizontal pass 32, leading to rear gas pass 34. Both the furnace and the rear pass contain other heat exchanger surface (not shown), for generating and superheating steam, as well known in the art.
- Pulverized coal generally ground to a flour-like consistency, is carried to each burner in a stream of air from the pulverizer melt 22.
- This air that carried the coal is generally referred to as the primary air.
- more air generally designated as secondary air, is introduced directly above and below the fuel-through nozzles 36. These nozzles are tiltable along with the nozzles 38 through the coal and primary air are introduced. This air is necessary for maintaining initial ignition and stable combustion conditions.
- the primary and secondary air constitutes about 20-30% of the total air required for complete or stoichiometric combustion of the coal.
- each secondary air nozzle 36 positioned above and below each secondary air nozzle 36 are auxiliary, or tertiary air nozzles 40.
- the remainder of the air necessary for complete combustion, or stoichiometric conditions, is introduced through these nozzles 40.
- Generally about 70-80% of the stoichiometric air is introduced through auxiliary nozzles 40.
- FIGs 3 and 4 the manner in which the coal and primary air, the secondary air, and the auxiliary air, is tangentially introduced into the furnace, is shown.
- the coal and primary air along with the secondary air are introduced into the furnace tangential to an imaginary circle 42 in the central portion of the furnace.
- the auxiliary air is introduced into the furnace tangential to an imaginary circle 44, at locations directly above and below the fire ball 42.
- the auxiliary air is introduced into the furnace rotating in a direction reverse, or opposite to the direction of rotation of the primary air and fuel. The result of this is a mixing and combustion efficiency much better than that realized with the usual tangentially fired furnace. This permits the use of less excess air in the furnace than previously required.
- the ultimate fire ball rising in the furnace rotates in a direction the same as that of the auxiliary air, since the mass introduced in this direction is several times that introduced in the opposite direction.
- the velocity of the auxiliary air is comparable to that of the primary and secondary air.
- the auxiliary air is introduced at a 5-15° agnle to the same vertical centerline of the furnace but opposite in direction. In this manner, the fuel and air are introducing swirl within the furnace in opposite directions. As stated previously, however, because of the greater mass and velocity of the auxiliary air, the ultimate overall swirl within the unit will be in the direction of the auxiliary air introduction.
- the top wall of the furnace is approximately 100 feet about the top burner elevation, and the excess, or overfire, air is introduced about 60 feet above the top burner elevations.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Combustion Of Fluid Fuel (AREA)
- Manufacture Of Iron (AREA)
Abstract
Description
- Pulverized coal has been successfully burned in suspension in furnaces by tangential firing methods for a long time. The technique involves introducing the coal and air into a furnace from the four corners thereof so that it is directed tangent to an imaginary circle in the center of the furnace. This type of firing has many advantages, among them being good mixing of the fuel and air, stable flame conditions, and long residence time of the combustion gases in the furnace. In recent times, it has become important to minimize air pollution as much as possible. Thus, some proposed changes have been made to the standard tangential firing method. One such arrangement is set forth in our pending agent application Serial No. 786,432, entitled "A Control System and Method for Operating a Tangentially Fired Pulverized Coal Furnace", filed on October 11, 1985. That application proposes introducing pulverized coal and air tangentially into the furnace from a number of lower burner levels in one direction, and introducing coal and air tangentially into the furnace from a number of upper burner levels in the opposite direction. By this arrangement, better mixing of the fuel and air is accomplished, thus permitting the use of less excess air than with a normal tangentially fired furnace, which generally is fired with 20-30% excess air. The reduction in excess air helps minimize the formation of NOx which is a major air pollutant of coal-fired furnaces. It also results in increased efficiency of the unit. Although the above firing technique reduces NOx, it does have some disadvantages. Since the reverse rotation of the gases in the furnace cancel each other out, the gases flow in a more or less straight line through the upper portion of the furnace, increasing the possibility of unburned carbon particles leaving the furnace due to reduced upper furnace turbulence and mixing. In addition, slag and unburned carbon deposits on the furnace walls can occur. These wall deposits reduce the efficiency of heat transfer to the water-cooled tubes lining the walls, increases the need for soot blowing, and reduces the life span of the tubes.
- In accordance with the invention, a furnace is provided in which pulverized coal in burned in suspension with good mixing of the coal and air, as is the case of the above-mentioned patent application. In addition, all of the advantages previously associated with tangentially fired furnaces are obtained, by having a swirling, rotating, fire ball in the furnace. The walls are protected by a blanket of air, reducing slagging thereof. This is accomplished by introducing coal and primary air into the furnace tangentially at a first level, introducing auxiliary air in an amount at least twice that of the primary air into the furnace tangentially at a second level directly above the first level, but in a direction opposite to that of the primary air, with there being a plurality of such first and second levels, one above the other. As a result of the greater mass and velocity of the auxiliary air, the ultimate swirl within the furnace will be in the direction of the auxiliary air introduction. Because of this, the fuel, which is introduced in a direction counter to the swirl of the furnace, is forced after entering the unit, to change direction to that of the overall furnace gases. Tremendous turbulent mixing between the fuel and air is thus created in this process. This increased mixing reduces the need for high levels of excess air within the furnace. This increased mixing also results in enhanced carbon conversion which improves the units over all heat release rate while at the same time reducing upper furnace slagging and fouling. The auxiliary air is directed at a circle of larger diameter than that of the fuel, thus forming a layer of air adjacent the walls. In addition, overfire air, consisting essentially of all of the excess air supplied to the furnace, is introduced into the furnace at a level considerably above all of the primary and auxiliary air introduction levels, with the overfire air being directed tangentially to an imaginary circle, and in a direction opposite to that of the auxiliary air.
-
- Figure 1 is a sectioned perspective of a tangentially fired pulverized coal furnace incorporating the invention;
- Figure 2 is an enlarged sectional view of one corner of burners;
- Figure 3 is a view taken on line 3-3 of Figure 1; and
- Figure 4 is a view taken on line 4-4 of Figure 1.
- Looking now to Figure 1, a coal-fired
furnace 10 is shown, having a plurality of levels ofburners 12 therein with each level having a burner mounted in each of the four corners thereof. Air is supplied to the burners fromfan 16 throughducts 18 and 20. Air is also supplied topulverizer 22 throughduct 24. Pulverized coal is transported to the burners in an air stream throughducts 26 and 28. There are separate air and fuel ducts leading to each individual burner, with separate valves and controls (not shown) also, so that each burner can be independently controlled. The combustion gases swirling upwardly in the furnace give up heat to the fluid passing through thetubes 30 lining all four of the furnace walls, before exiting the furnace throughhorizontal pass 32, leading torear gas pass 34. Both the furnace and the rear pass contain other heat exchanger surface (not shown), for generating and superheating steam, as well known in the art. - The specific manner of introducing the fuel and air into the furnace will now be described in more detail. Pulverized coal, generally ground to a flour-like consistency, is carried to each burner in a stream of air from the
pulverizer melt 22. This air that carried the coal is generally referred to as the primary air. As best seen in Figure 2, more air, generally designated as secondary air, is introduced directly above and below the fuel-throughnozzles 36. These nozzles are tiltable along with thenozzles 38 through the coal and primary air are introduced. This air is necessary for maintaining initial ignition and stable combustion conditions. The primary and secondary air constitutes about 20-30% of the total air required for complete or stoichiometric combustion of the coal. - Still looking at Figure 2, positioned above and below each
secondary air nozzle 36 are auxiliary, ortertiary air nozzles 40. The remainder of the air necessary for complete combustion, or stoichiometric conditions, is introduced through thesenozzles 40. Generally about 70-80% of the stoichiometric air is introduced throughauxiliary nozzles 40. - Looking now to Figures 3 and 4, the manner in which the coal and primary air, the secondary air, and the auxiliary air, is tangentially introduced into the furnace, is shown. As seen in Figure 3, the coal and primary air along with the secondary air, are introduced into the furnace tangential to an
imaginary circle 42 in the central portion of the furnace. Looking now to Figure 4, it can be seen that the auxiliary air is introduced into the furnace tangential to animaginary circle 44, at locations directly above and below thefire ball 42. The auxiliary air is introduced into the furnace rotating in a direction reverse, or opposite to the direction of rotation of the primary air and fuel. The result of this is a mixing and combustion efficiency much better than that realized with the usual tangentially fired furnace. This permits the use of less excess air in the furnace than previously required. The ultimate fire ball rising in the furnace rotates in a direction the same as that of the auxiliary air, since the mass introduced in this direction is several times that introduced in the opposite direction. The velocity of the auxiliary air is comparable to that of the primary and secondary air. The above feature, coupled with the face that the auxiliary air is introduced tangential to acircle 44 larger than thecircle 42, keeps a blanket of air adjacent to the furnace walls, thereby minimizing slagging on these walls. - Looking again at Figure 1, all of the excess air is introduced into the furnace in the upper portion thereof. This excess, or overfire, air is introduced through nozzles 50, which are directed tangential to an imaginary circle 52, in a direction opposite to that of the rising fire ball; i.e opposite to the direction of introduction of the
auxiliary air 44. Since the amount of excess air is relatively small (5-20%), the flow leaving the furnace will still be swirling or rotating somewhat in the direction of rotation of the auxiliary air introduction. This causes some temperature unbalancing the gases leaving the furnace. Some statistical data of the proposed modified furnace will now be given. The primary air and fuel are introduced into the unit at a 6° angle to the radial line from the vertical centerline axis of the furnace. The auxiliary air is introduced at a 5-15° agnle to the same vertical centerline of the furnace but opposite in direction. In this manner, the fuel and air are introducing swirl within the furnace in opposite directions. As stated previously, however, because of the greater mass and velocity of the auxiliary air, the ultimate overall swirl within the unit will be in the direction of the auxiliary air introduction. There can be as many as six elevations of burners; i.e. 24 in total, with six in each corner. These can be spread over a 30-foot height in the furnace beginning 50 feet above the opening in the coutant furnace bottom. The top wall of the furnace is approximately 100 feet about the top burner elevation, and the excess, or overfire, air is introduced about 60 feet above the top burner elevations.
Claims (5)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US843419 | 1986-03-21 | ||
US84341986A | 1986-03-24 | 1986-03-24 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0238907A2 true EP0238907A2 (en) | 1987-09-30 |
EP0238907A3 EP0238907A3 (en) | 1988-11-09 |
EP0238907B1 EP0238907B1 (en) | 1991-07-24 |
Family
ID=25289919
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP87103150A Expired - Lifetime EP0238907B1 (en) | 1986-03-24 | 1987-03-05 | Low excess air tangential firing system |
Country Status (11)
Country | Link |
---|---|
EP (1) | EP0238907B1 (en) |
JP (1) | JPS62233610A (en) |
KR (1) | KR900006241B1 (en) |
CN (1) | CN1005589B (en) |
AU (1) | AU583717B2 (en) |
CA (1) | CA1273248A (en) |
DE (1) | DE3771537D1 (en) |
DK (1) | DK147587A (en) |
ES (1) | ES2025077B3 (en) |
IN (1) | IN168173B (en) |
ZA (1) | ZA872065B (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0405294A2 (en) * | 1989-06-24 | 1991-01-02 | Balcke-Dürr AG | Device for combustion fuels in a combustion chamber |
US5429060A (en) * | 1989-11-20 | 1995-07-04 | Mitsubishi Jukogyo Kabushiki Kaisha | Apparatus for use in burning pulverized fuel |
EP0915290A1 (en) * | 1997-11-08 | 1999-05-12 | L. & C. Steinmüller GmbH | Method for combusting of fuel dust in a tangential firing device and tangential firing device |
CN100427824C (en) * | 2005-12-23 | 2008-10-22 | 浙江大学 | Adjacent angle displacement direct burner system |
CN100451447C (en) * | 2006-11-30 | 2009-01-14 | 上海交通大学 | Combustion method of anthracite coal |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2663723B1 (en) * | 1990-06-20 | 1995-07-28 | Air Liquide | PROCESS AND INSTALLATION FOR MELTING A LOAD IN THE OVEN. |
US20040221777A1 (en) * | 2003-05-09 | 2004-11-11 | Alstom (Switzerland) Ltd | High-set separated overfire air system for pulverized coal fired boilers |
CN100491821C (en) * | 2007-06-28 | 2009-05-27 | 上海交通大学 | Dense-phase back-flushing multiple level NOx combustion method |
CN101852429A (en) * | 2010-06-29 | 2010-10-06 | 哈尔滨工业大学 | Wall-arranged direct-flow pulverized coal combustion device with side secondary air |
CN102032555A (en) * | 2010-12-07 | 2011-04-27 | 上海锅炉厂有限公司 | Boiler combustion device |
JP6087793B2 (en) * | 2013-11-15 | 2017-03-01 | 三菱日立パワーシステムズ株式会社 | boiler |
JP6246709B2 (en) * | 2014-12-19 | 2017-12-13 | 三菱日立パワーシステムズ株式会社 | Combustion burner and boiler |
CN104848544B (en) * | 2015-04-21 | 2017-12-26 | 武汉轻工大学 | A kind of liquid medium heat conducting furnace for revolving floating burning |
CN111999429B (en) * | 2020-09-01 | 2022-06-21 | 中北大学 | Quasi-static simulator for high-temperature fireball |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB697840A (en) * | 1951-04-12 | 1953-09-30 | Babcock & Wilcox Ltd | Improvements in or relating to pulverised fuel furnaces |
US4501204A (en) * | 1984-05-21 | 1985-02-26 | Combustion Engineering, Inc. | Overfire air admission with varying momentum air streams |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4438709A (en) * | 1982-09-27 | 1984-03-27 | Combustion Engineering, Inc. | System and method for firing coal having a significant mineral content |
DE3531571A1 (en) * | 1985-09-04 | 1987-03-05 | Steinmueller Gmbh L & C | METHOD FOR BURNING FUELS WITH A REDUCTION IN NITROGEN OXIDATION AND FIRE FOR CARRYING OUT THE METHOD |
-
1987
- 1987-03-04 IN IN168/CAL/87A patent/IN168173B/en unknown
- 1987-03-04 CA CA000531079A patent/CA1273248A/en not_active Expired - Fee Related
- 1987-03-05 EP EP87103150A patent/EP0238907B1/en not_active Expired - Lifetime
- 1987-03-05 ES ES87103150T patent/ES2025077B3/en not_active Expired - Lifetime
- 1987-03-05 DE DE8787103150T patent/DE3771537D1/en not_active Expired - Fee Related
- 1987-03-18 CN CN87102205.2A patent/CN1005589B/en not_active Expired
- 1987-03-20 ZA ZA872065A patent/ZA872065B/en unknown
- 1987-03-23 AU AU70503/87A patent/AU583717B2/en not_active Ceased
- 1987-03-23 DK DK147587A patent/DK147587A/en not_active Application Discontinuation
- 1987-03-24 KR KR1019870002677A patent/KR900006241B1/en not_active IP Right Cessation
- 1987-03-24 JP JP62068129A patent/JPS62233610A/en active Granted
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB697840A (en) * | 1951-04-12 | 1953-09-30 | Babcock & Wilcox Ltd | Improvements in or relating to pulverised fuel furnaces |
US4501204A (en) * | 1984-05-21 | 1985-02-26 | Combustion Engineering, Inc. | Overfire air admission with varying momentum air streams |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0405294A2 (en) * | 1989-06-24 | 1991-01-02 | Balcke-Dürr AG | Device for combustion fuels in a combustion chamber |
EP0405294A3 (en) * | 1989-06-24 | 1991-10-02 | Balcke-Duerr Ag | Device for combustion fuels in a combustion chamber |
US5429060A (en) * | 1989-11-20 | 1995-07-04 | Mitsubishi Jukogyo Kabushiki Kaisha | Apparatus for use in burning pulverized fuel |
EP0915290A1 (en) * | 1997-11-08 | 1999-05-12 | L. & C. Steinmüller GmbH | Method for combusting of fuel dust in a tangential firing device and tangential firing device |
CN100427824C (en) * | 2005-12-23 | 2008-10-22 | 浙江大学 | Adjacent angle displacement direct burner system |
CN100451447C (en) * | 2006-11-30 | 2009-01-14 | 上海交通大学 | Combustion method of anthracite coal |
Also Published As
Publication number | Publication date |
---|---|
CN1005589B (en) | 1989-10-25 |
CN87102205A (en) | 1987-11-18 |
JPH0429926B2 (en) | 1992-05-20 |
DK147587A (en) | 1987-09-25 |
AU583717B2 (en) | 1989-05-04 |
AU7050387A (en) | 1987-10-01 |
IN168173B (en) | 1991-02-16 |
EP0238907B1 (en) | 1991-07-24 |
ZA872065B (en) | 1987-11-25 |
EP0238907A3 (en) | 1988-11-09 |
ES2025077B3 (en) | 1992-03-16 |
DK147587D0 (en) | 1987-03-23 |
KR900006241B1 (en) | 1990-08-27 |
CA1273248A (en) | 1990-08-28 |
JPS62233610A (en) | 1987-10-14 |
DE3771537D1 (en) | 1991-08-29 |
KR870009175A (en) | 1987-10-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4715301A (en) | Low excess air tangential firing system | |
EP0022454B1 (en) | Furnace with sets of nozzles for tangential introduction of pulverized coal, air and recirculated gases | |
EP0554250B1 (en) | A clustered concentric tangential firing system | |
US4672900A (en) | System for injecting overfire air into a tangentially-fired furnace | |
US5195450A (en) | Advanced overfire air system for NOx control | |
EP0238907A2 (en) | Low excess air tangential firing system | |
CN1331788A (en) | Method of operating tangential firing system | |
US4426939A (en) | Method of reducing NOx and SOx emission | |
US5343820A (en) | Advanced overfire air system for NOx control | |
IL171017A (en) | High set separated overfire air system for pulverized coal fired furnace | |
US5329866A (en) | Combined low NOx burner and NOx port | |
US5899172A (en) | Separated overfire air injection for dual-chambered furnaces | |
EP0554254B1 (en) | AN ADVANCED OVERFIRE AIR SYSTEM FOR NOx CONTROL | |
RU2006741C1 (en) | Furnace | |
RU2050506C1 (en) | Combustion chamber | |
Larue et al. | Combined low NO x burner and NO x port | |
Marion et al. | Advanced overfire air system for NOx control | |
Basu et al. | Design of Novel Burners | |
Winship et al. | Method of reducing NO x and SO x emission |
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: A2 Designated state(s): BE DE ES FR GB IT NL SE |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): BE DE ES FR GB IT NL SE |
|
17P | Request for examination filed |
Effective date: 19890424 |
|
17Q | First examination report despatched |
Effective date: 19900710 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE DE ES FR GB IT NL SE |
|
REF | Corresponds to: |
Ref document number: 3771537 Country of ref document: DE Date of ref document: 19910829 |
|
ITF | It: translation for a ep patent filed |
Owner name: ING. ZINI MARANESI & C. S.R.L. |
|
ET | Fr: translation filed | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19911223 Year of fee payment: 6 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 19920102 Year of fee payment: 6 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19920107 Year of fee payment: 6 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2025077 Country of ref document: ES Kind code of ref document: B3 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19920331 Year of fee payment: 6 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19930306 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Effective date: 19930331 |
|
BERE | Be: lapsed |
Owner name: COMBUSTION ENGINEERING INC. Effective date: 19930331 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19931001 |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Effective date: 19931130 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19941230 Year of fee payment: 9 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19941231 Year of fee payment: 9 |
|
EUG | Se: european patent has lapsed |
Ref document number: 87103150.6 Effective date: 19931008 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19960305 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19960305 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19961203 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: ES Payment date: 19970320 Year of fee payment: 11 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 19980306 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 20000201 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED. Effective date: 20050305 |