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US5403378A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for protecting an injection device disposed in a hot blast conduit of a blast furnace

Assignee: Kortec AG
•
Filing: 1993-06-29
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Granted: 1995-04-04
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Expires: 2013-06-29
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Abstract

Abstract To prevent burn-back at a coal dust injection lance which projects into a hot blast conduit of a blast furnace, cooling is effected using atomized coolant. Water is preferred as the coolant. The carrier gas used for the atomized water is either air or the oxygen which is injected through the lance for complete combustion of the coal dust.

Inventors

  • 👤 William Wells
  • 👤 Ralph Weber

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 18:56
CPC Classifications
C; C21; C21B; C21B5/00; C21B5/001; C21B5/003

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 109 words
A method of cooling an injection lance having a discharge end which extends into a hot blast conduit furnace comprising the steps of providing said injection lance with at least two tubes, which are concentrically arranged and radially spaced from each other to form a central duct and a first annular duct, each of said tubes being open at said discharge end for injecting material into said hot blast conduit, injecting a fine grain solid fuel into said hot blast conduit through a first one of said tubes, and injecting a cooling means, through another of said tubes, for the evaporative cooling of said first one of said tubes.
Claim 2
Independent Claim 109 words
A method of cooling an injection lance having a discharge end which extends into a hot blast conduit furnace comprising the steps of providing said injection lance with at least two tubes, which are concentrically arranged and radially spaced from each other to form a central duct and a first annular duct, each of said tubes being open at said discharge end for injecting material into said hot blast conduit, injecting a fine grain solid fuel into said hot blast conduit through a first one of said tubes, and injecting a cooling means, through another of said tubes, for the evaporative cooling of said first one of said tubes.
Claim 3
Dependent Claim 36 words
A method according to claim 1, wherein said fine grain solid is injected through said central duct, and said injecting of a cooling means includes injecting a spray mist of water through said first annular duct.
Claim 4
Dependent Claim 65 words
A method according to claim 1 including the step of providing said injection lance with a third tube open at said discharge end for injecting a material into said hot blast conduit, and concentrically arranged with and radially spaced from said other two tubes to thereby form a second annular duct having an annular shape and surrounding said central duct and said first annular duct.
Claim 5
Dependent Claim 34 words
A method according to claim 3, wherein said fuel is injected through said first duct, an oxygen-bearing gas is injected through said second duct, and said cooling means is injected through said third duct.
Claim 6
Dependent Claim 25 words
A method according to claim 1 wherein said injecting of fine grain solid fuel includes mixing an oxygen-bearing gas with a fine grain solid fuel.
Claim 7
Dependent Claim 15 words
A method according to claim 1, wherein said fine grain solid fuel includes coal dust.
Claim 8
Dependent Claim 100 words
An injection apparatus having a discharge end which extends into a hot blast conduit of a blast furnace comprising at least two tubes which are concentrically arranged and radially spaced from each other to form a central duct and a first annular duct, each of said tubes being open at said discharge end for injecting material into said hot blast conduit, a first one of said tubes for injecting a fine grain solid fuel into said hot blast conduit, and another of said tubes for injecting a cooling means for the evaporative cooling of said first one of said tubes.
Claim 9
Dependent Claim 100 words
An injection apparatus having a discharge end which extends into a hot blast conduit of a blast furnace comprising at least two tubes which are concentrically arranged and radially spaced from each other to form a central duct and a first annular duct, each of said tubes being open at said discharge end for injecting material into said hot blast conduit, a first one of said tubes for injecting a fine grain solid fuel into said hot blast conduit, and another of said tubes for injecting a cooling means for the evaporative cooling of said first one of said tubes.
Claim 10
Dependent Claim 72 words
An injection apparatus according to claim 7 wherein said tubes are removably inserted through an opening in a wall of said hot blast conduit, and further comprising attachment means for attaching said injection apparatus to an outside portion of said wall of said hot blast conduit, and said attachment means comprises closing means for automatically closing said opening in said wall of said hot blast conduit upon removal of said tube means.
Claim 11
Dependent Claim 32 words
An injection apparatus according to claim 7, wherein said fuel is injected through said central duct, and said cooling means is a spray mist of water injected through said first annular duct.
Claim 12
Dependent Claim 59 words
An injection apparatus according to claim 7, further comprising a third tube open at said discharge end for injecting material into said hot blast conduit, and being concentrically arranged with and radially spaced from said other tube tubes to thereby form a second annular duct having an annular shape and surrounding said central duct and said first annular duct.
Claim 13
Dependent Claim 42 words
An injection apparatus according to claim 7, wherein said fuel is injected through said central duct, an oxygen-bearing gas is injected through said first annular duct, and said cooling means is a spray mist of water injected through said second annular duct.

References Cited (Backward Citations)

US1518854A Cited
SU532624A1 Cited
US4700930A Cited
US4887800A Cited
WO1991014791A1 Cited
US5018458A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-04-03 1998-10-03 1999-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-04-03 2002-10-03 2003-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-04-03 2006-10-03 2007-04-04 $7700.00 Window Closed / Lapsed

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