← Back to Patent Explorer
US4438707A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for directly igniting low-grade solid fuel powders in cold combustion chambers

Assignee: Stein Industrie SA
•
Filing: 1982-02-08
•
Granted: 1984-03-27
•
Expires: 2002-02-08
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An apparatus allowing the use of low-grade solid fuel powders (coal, lignite, peat) and products derived therefrom during cold starting periods and for backing up combustion chamber operation at low load. The pilot burner (1) has an auxiliary and pilot igniter which burns gas produced by gasifying low-grade fuel in a gasification unit (6) and a main igniter which burns the low-grade fuel powder in a storage silo (5). The combustion air is heated in an air heater (10) by the gas produced by gasifying low-grade fuel in gasification unit (6). In particular, turbulence is set up in the combustion air sent to the outlet of the pilot igniter. Application to combustion apparatus including steam generators of thermal power stations.

Inventors

  • 👤 Lucien Delaplace
  • 👤 Jacques Robert

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 17:16
CPC Classifications
F; F23; F23C; F23C1/00; F23C1/12; F23D; F23D1/00; F23D17/00; F23D17/005

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 73 words
Ignition apparatus for directly igniting low-grade solid fuel powders in cold combustion chambers, said apparatus comprising at least one pilot burner with at least one pilot igniter and at least one main igniter, said at least one main igniter being fed with low-grade fuel powders, the improvement comprising: means for feeding said pilot igniter with low-grade gas from a gasifying unit gasifying said low-grade fuel powders to eliminate adding any auxiliary high-grade fuel.
Claim 2
Dependent Claim 73 words
Ignition apparatus for directly igniting low-grade solid fuel powders in cold combustion chambers, said apparatus comprising at least one pilot burner with at least one pilot igniter and at least one main igniter, said at least one main igniter being fed with low-grade fuel powders, the improvement comprising: means for feeding said pilot igniter with low-grade gas from a gasifying unit gasifying said low-grade fuel powders to eliminate adding any auxiliary high-grade fuel.
Claim 3
Dependent Claim 97 words
Ignition apparatus according to claim 1, comprising a combustion chamber body having a cylindro-conical portion, which includes both air distribution units to facilitate combustion, and at least one pilot burner constituted by a pilot igniter and a main igniter which is fed by a pipe which brings in air and fuel powder and whose outlet is disposed axially relative to the cylindro-conical portion of the combustion chamber, and wherein said low-grade gas pilot igniter is disposed upstream from said end of the fuel powder pipe in a position parallel to and to one side of said pipe.
Claim 4
Dependent Claim 117 words
Ignition apparatus according to claim 1, comprising a combustion chamber body having a cylindro-conical portion which includes both air distribution units to facilitate combustion, and at least one pilot burner constituted by a pilot igniter and a main igniter which is fed by a pipe which brings in air and fuel powder and whose outlet is disposed axially relative to the cylindro-conical portion of the combustion chamber, and wherein at least one low-grade gas pilot igniter is disposed downstream from said end of the fuel powder pipe in a direction parallel to said pipe and having its outlet at a portion of the side surface of the conical part of the cylindro-conical portion of the combustion chamber.
Claim 5
Dependent Claim 39 words
Ignition apparatus according to claim 2 or 3, wherein said air distribution units is preceded by an air heater which burns low-grade gas produced by said gasifying unit and includes means for supplying heated air to said pilot burner.
Claim 6
Dependent Claim 53 words
Ignition apparatus according to claim 4, wherein said heated air supply means comprises means for feeding said heated air to the inlet of said pilot igniter at the same time as the low-grade gas, and said apparatus further includes means for feeding secondary air in which turbulance is set up to its outlet.
Claim 7
Dependent Claim 32 words
Ignition apparatus according to claim 5, wherein vanes disposed perpendicularly to the outlet of said pilot igniter of low-grade gas makes said secondary air rotate to set up the secondary air turbulance.
Claim 8
Dependent Claim 26 words
Ignition apparatus according to claim 5, wherein a helical screw disposed concentrically around said low-grade fuel powder pipe sets up the turbulance of said secondary air.
Claim 9
Dependent Claim 23 words
Ignition apparatus according to claims 1 or 7 wherein said pilot burners are disposed between two main burners which are adjacent to them.
Claim 10
Dependent Claim 33 words
Ignition apparatus according to claim 8, wherein the combustion chamber is parallelepipedical, and the burner units constituted by said pilot igniters and main igniters are located in the corners of the combustion chamber.
Claim 11
Dependent Claim 33 words
Ignition apparatus according to claim 8, wherein the combustion chamber is parallelepipedical, and the burner units constituted by said pilot burners and main burners are located on one surface of the combustion chamber.

References Cited (Backward Citations)

FR870016A Cited
DE922297C Cited
DE928360C Cited
US3934522A Cited
US4173189A Cited
FR2381242A1 Cited
US4221174A Cited
US4228747A Cited
US4241673A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-03-27 1987-09-26 1988-03-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-03-27 1991-09-26 1992-03-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-03-27 1995-09-26 1996-03-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag