US3772998A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for the combustion of sludge
Assignee: METTALGES AG
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Filing: 1971-07-09
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Granted: 1973-11-20
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Expires: 1991-07-09
Abstract
Abstract A method of and an apparatus for the combustion of sludge obtained from a clarifier in the purification of water, wherein the clarifier sludge is passed through a multistage drier above a fluidized-bed furnace in which it is predried with the waste mass of the latter. As the wastes dry, they are comminuted and distributed over the cross section of the fluidized-bed furnace for burning therein.
Inventors
- 👤 R Menigat
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:51
CPC Classifications
C; C02; C02F; C02F11/00; C02F11/06; F; F23; F23G; F23G5/00; F23G5/24; F23G5/28; F23G5/30; F23G2201/00; F23G2201/10; F23G2201/80; F23G2206/00; F23G2206/10; F23G2209/00; F23G2209/12; Y; Y02; Y02W; Y02W10/00; Y02W10/40
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
144 words
A method of burning a sludge containing combustible solids comprising the steps of: simultaneously drying the sludge to produce solids and comminuting said solids by contacting the flowable material with an exhaust gas by passing the sludge onto a plurality of vertically spaced platforms and scraping material from said platforms while inducing the material to pass downwardly from one platform to another distributing the comminuted solids over the cross-section of a fluidized bed directly below said platforms by causing the material to fall freely from the lowest platform onto said bed; burning said solids in said fluidized bed in the presence of oxygen-containing fluidized gas to produce said exhaust gases and causing said exhaust gases to flow upwardly over the material on said platform; and recovering gases evolved from said material upon the drying thereof and and recycling said gas to said fluidized bed.
Claim 2
Independent Claim
144 words
A method of burning a sludge containing combustible solids comprising the steps of: simultaneously drying the sludge to produce solids and comminuting said solids by contacting the flowable material with an exhaust gas by passing the sludge onto a plurality of vertically spaced platforms and scraping material from said platforms while inducing the material to pass downwardly from one platform to another distributing the comminuted solids over the cross-section of a fluidized bed directly below said platforms by causing the material to fall freely from the lowest platform onto said bed; burning said solids in said fluidized bed in the presence of oxygen-containing fluidized gas to produce said exhaust gases and causing said exhaust gases to flow upwardly over the material on said platform; and recovering gases evolved from said material upon the drying thereof and and recycling said gas to said fluidized bed.
Claim 3
Dependent Claim
20 words
The method defined in claim 1 wherein said material is a sludge obtained from the treatment of water or sewage.
Claim 4
Dependent Claim
55 words
The method defined in claim 2 wherein said fluidized bed is a bed of quartz and is maintained at a temperature such that said exhaust gas is at a temperature of 800* to 900*C, said method further comprising the step of releasing to the atmosphere gases contacting said material only from above said fluidized bed.
Claim 5
Dependent Claim
24 words
The method defined in claim 3 wherein the recycled gas is introduced into said fluidized bed substantially in the region of the top thereof.
Claim 6
Independent Claim
172 words
An apparatus for the combustion of a flowable material containing organic solids, comprising housing means forming a fluidized-bed chamber, a flow chamber above said fluidized bed chamber and a drying zone above said flow chamber; a grate below the fluidized-bed chamber; means for introducing an oxygen-containing fluidizing gas through said grate and into a fluidized bed sustained thereabove for burning organic solids cascading through said flow chamber onto said fluidized bed; a plurality of vertically spaced hearths in said drying zone; means for introducing said flowable material containing said organic solids at an upper one of said hearths; rotary take means sweeping across said hearths for comminuting said solids while drying same by passing said solids downwardly from hearth to hearth in said zone; means for discharging dried comminutd solids from the lowermost hearth onto said fluidized bed, and for passing an exhaust gas rising from said fluidized bed through said zone to dry the solids therein; and means for collecting gases in said zone and recycling same to said fluidized bed.
Claim 7
Independent Claim
172 words
An apparatus for the combustion of a flowable material containing organic solids, comprising housing means forming a fluidized-bed chamber, a flow chamber above said fluidized bed chamber and a drying zone above said flow chamber; a grate below the fluidized-bed chamber; means for introducing an oxygen-containing fluidizing gas through said grate and into a fluidized bed sustained thereabove for burning organic solids cascading through said flow chamber onto said fluidized bed; a plurality of vertically spaced hearths in said drying zone; means for introducing said flowable material containing said organic solids at an upper one of said hearths; rotary take means sweeping across said hearths for comminuting said solids while drying same by passing said solids downwardly from hearth to hearth in said zone; means for discharging dried comminutd solids from the lowermost hearth onto said fluidized bed, and for passing an exhaust gas rising from said fluidized bed through said zone to dry the solids therein; and means for collecting gases in said zone and recycling same to said fluidized bed.
Claim 8
Dependent Claim
32 words
The apparatus defined in claim 5 wherein the last-mentioned means includes a source of compressed air and suction means operated by said compressed air for maintaining a subatmospheric pressure above said hearths.
Claim 9
Dependent Claim
94 words
The apparatus defined in claim 6 wherein said hearths are provided alternately with downcomers at their inner and outer peripheries, said rake means including an air-cooled hollow shaft extending centrally through said zone and having radial arms sweeping over each of said hearths, said arms being provided with rake teeth inclined to the direction of rotation for sweeping said solids toward the respective downcomer, said grate being provided with a wind box connected to said source, said apparatuS further comprising means for venting said housing means to the atmosphere only at said flow chamber.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |