Patent US4274836A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4274836A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for improving bed firing characteristics and inhibiting coalescence of coal pellets

Assignee: CTI-NUCLEAR Inc (FORMERLY MCDOWELL-WELLMAN COMPANY)
•
Filing: 1979-04-20
•
Granted: 1981-06-23
•
Expires: 1999-04-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract There is disclosed a method of reducing the swelling characteristics and bed characteristics of a pelletized fuel during a sintering operation. The method comprises the steps of pulverizing the coal to form a powdery mass, forming the mass into discrete pellets, providing a coating on the pellets with soluble salts, burnt lime, or hydrated lime, and heating the pellets to a temperature exceeding 800° F.

Inventors

  • 👤 Thomas E. Ban
  • 👤 William H. Marlowe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:35
CPC Classifications
C; C10; C10L; C10L5/00; C10L5/02

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 73 words
A method of reducing the swelling characteristics and bed coalescence characteristics of a pelletized fuel during a sintering operation comprising the steps of pulverizing the coal to form a powdery mass, forming said mass into discrete pellets, providing on the surface of said pellets a coating substance selected from the group consisting of sodium carbonate, burnt lime, and hydrated lime, drying said pellets and heating said pellets to a temperature exceeding 800° F.
Claim 2
Independent Claim 73 words
A method of reducing the swelling characteristics and bed coalescence characteristics of a pelletized fuel during a sintering operation comprising the steps of pulverizing the coal to form a powdery mass, forming said mass into discrete pellets, providing on the surface of said pellets a coating substance selected from the group consisting of sodium carbonate, burnt lime, and hydrated lime, drying said pellets and heating said pellets to a temperature exceeding 800° F.
Claim 3
Dependent Claim 15 words
A method according to claim 1, wherein powdered limestone is mixed with said powdery mass.
Claim 4
Dependent Claim 17 words
A method according to claim 2, wherein said powdered limestone is present in amounts of about 20%.
Claim 5
Dependent Claim 29 words
A method according to claim 1, wherein the coating substance is initially mixed with the powdery mass and migrates to the surface of the pellets during the drying step.
Claim 6
Dependent Claim 13 words
A method according to claim 4, wherein said coating substance is sodium carbonate.
Claim 7
Dependent Claim 22 words
A method according to claim 5, wherein said sodium carbonate is present in amounts of between 1 and 5 percent by weight.
Claim 8
Dependent Claim 24 words
A method according to claim 1, wherein said coated material is deposited directly on the surface of the pellet prior to drying the pellet.
Claim 9
Dependent Claim 12 words
A method according to claim 7, wherein said coating material is lime.
Claim 10
Dependent Claim 21 words
A method according to claim 8, wherein said lime is present in amounts of between 4 and 10 percent by weight.
Claim 11
Dependent Claim 22 words
A method according to claim 1, wherein recycled fired pellets are layered onto the discrete green pellets prior to heating the pellets.

References Cited (Backward Citations)

US150393A Cited
US394486A Cited
US486100A Cited
US1860743A Cited
US2336154A Cited
US2729598A Cited
US3068080A Cited
US4111755A Cited
US4148613A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-06-22 1984-12-22 1985-06-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-06-22 1988-12-22 1989-06-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-06-22 1992-12-22 1993-06-23 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag