US4387653A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Limestone-based sorbent agglomerates for removal of sulfur compounds in hot gases and method of making
Assignee: BASF Catalysts LLC
•
Filing: 1981-10-05
•
Granted: 1983-06-14
•
Expires: 2001-10-05
Abstract
Abstract Sulfur-containing compounds such as hydrogen sulfide and sulfur oxides arising from gasification or combustion of organic fuels such as coal may be removed from the hot gases by attrition resistant, highly reactive limestone-based sorbent agglomerates. The agglomerates are formed by crushing and powdering naturally occurring limestone into grains of fine particle size and binding the powdered limestone grains with a binder that is stable at high temperature, for example a colloidal grade of attapulgite clay. Volatile liquid is added to the mix of binder and powdered limestone to form a paste-like mixture, which is then agglomerated in compression-type agglomerating equipment to form spheroidal agglomerates having good green strength. In fluidized bed combustion applications, these agglomerates have attrition resistance equivalent to conventional natural limestone granules and are far more reactive in terms of sulfur pickup.
Inventors
- 👤 Kenneth E. Voss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:22
CPC Classifications
F; F23; F23C; F23C10/00; F23C10/002; B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/508; B01D53/52; B01D53/523; B01J; B01J20/00; B01J20/02; B01J20/04; B01J20/043; B01J20/28; B01J20/28014; B01J20/2803; B01J20/30; B01J20/3021; B01J20/3028; B01J20/3042; B01J20/34; B01J20/3433; B01J20/345; B01J20/3458
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
97 words
In a process for fluidized bed combustion of sulfur containing fuel such as coal or heavy oil, wherein said fuel generates sulfur oxides in the flue gas stream upon combustion, and limestone is added to said bed to react with said sulfur oxides to remove them from the flue gas stream, the improvement which comprises enhancing the removal of sulfur oxides by utilizing said limestone in the form of agglomerates comprising fine grains of naturally occurring, uncalcined limestone and a cementitious clay selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof in binder-effective amount.
Claim 2
Dependent Claim
97 words
In a process for fluidized bed combustion of sulfur containing fuel such as coal or heavy oil, wherein said fuel generates sulfur oxides in the flue gas stream upon combustion, and limestone is added to said bed to react with said sulfur oxides to remove them from the flue gas stream, the improvement which comprises enhancing the removal of sulfur oxides by utilizing said limestone in the form of agglomerates comprising fine grains of naturally occurring, uncalcined limestone and a cementitious clay selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof in binder-effective amount.
Claim 3
Dependent Claim
95 words
In a process for fixed bed combustion of sulfur containing solid fuel such as coal, wherein said fuel generates sulfur oxides in the flue gas stream upon combustion, and limestone mingled with the coal in said bed to react with said sulfur oxides to remove them from the flue gas stream, the improvement which comprises enhancing the removal of sulfur oxides by utilizing said limestone in the form of agglomerates comprising finely powdered, naturally occurring, uncalcined limestone and cementitious clay selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof in binder-effective amount.
Claim 4
Dependent Claim
95 words
In a process for fixed bed combustion of sulfur containing solid fuel such as coal, wherein said fuel generates sulfur oxides in the flue gas stream upon combustion, and limestone mingled with the coal in said bed to react with said sulfur oxides to remove them from the flue gas stream, the improvement which comprises enhancing the removal of sulfur oxides by utilizing said limestone in the form of agglomerates comprising finely powdered, naturally occurring, uncalcined limestone and cementitious clay selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof in binder-effective amount.
Claim 5
Dependent Claim
11 words
The process of claim 2 wherein said solid fuel is coal.
Claim 6
Dependent Claim
42 words
In a process for removing hydrogen sulfide from gases, the improvement which comprises utilizing agglomerates comprising fine grains of naturally occurring, uncalcined limestone and a cementitious clay, selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof, in binder-effective amount.
Claim 7
Dependent Claim
42 words
In a process for removing hydrogen sulfide from gases, the improvement which comprises utilizing agglomerates comprising fine grains of naturally occurring, uncalcined limestone and a cementitious clay, selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof, in binder-effective amount.
Claim 8
Dependent Claim
42 words
In a process for removing sulfur oxides from gases, the improvement which comprises utilizing agglomerates comprising fine grains of naturally occurring, uncalcined limestone and a cementitious clay, selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof, in binder-effective amount.
Claim 9
Dependent Claim
42 words
In a process for removing sulfur oxides from gases, the improvement which comprises utilizing agglomerates comprising fine grains of naturally occurring, uncalcined limestone and a cementitious clay, selected from the group consisting of attapulgite, sepiolite, smectite and mixtures thereof, in binder-effective amount.
Claim 10
Dependent Claim
35 words
The process of claims 1, 2, 4, or 5 wherein at least a portion of said agglomerates are recovered, regenerated and recycled to further charge of fuel after initial use for removal of sulfur compounds.
References Cited (Backward Citations)
US4115518A
Cited
US3976747A
Cited
US4108969A
Cited
US4177158A
Cited
US4262610A
Cited
US4312280A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-13 | 1986-12-13 | 1987-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-13 | 1990-12-13 | 1991-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-13 | 1994-12-13 | 1995-06-14 | $7700.00 | Window Closed / Lapsed |