US4242220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Waste disposal method using microwaves
Assignee: KIMIHARU SATO A JAPAN CORP
•
Filing: 1978-07-31
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Granted: 1980-12-30
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Expires: 1998-07-31
Abstract
Abstract Waste such as sludge containing poisonous substances is processed into a safe article by removing water in a usual manner, drying the waste to substantial dryness by microwave heating, mixing the dry waste powder with a thermoplastic resin, irradiating the mixture with microwaves to encapsulate the waste particles with the resin and to heat polymerize the resin, and molding the resin encapsulated particles into an article.
Inventors
- 👤 Gentaku Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:29
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/30; C02F1/302; C02F11/00; C02F11/004; C02F11/008; G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/08; G21F9/28; G21F9/30; G21F9/301; G21F9/307; Y; Y10; Y10S; Y10S264/00; Y10S264/911
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
145 words
A method of manufacturing a safe article from a water-containing waste having poisonous substances, comprising the steps of: (a) removing a major portion of water contained in the waste, (b) stirring the waste during the subsequent steps except for the last step, (c) drying the waste to a residual water content of about 12-13% by weight, without igniting flammable material contained in the waste, (d) microwave heating the waste to further reduce the residual water content to 0.1-5% by weight so that the waste becomes powdery, (e) cooling the waste powder to room temperature, (f) contacting the waste powder with a thermoplastic resin, (g) microwave heating the mixture of the waste powder and the thermoplastic resin at a rate which enables the resin to melt and encapsulate the waste powder particles, and (h) molding the resin encapsulated particles into an article having a desired shape.
Claim 2
Independent Claim
145 words
A method of manufacturing a safe article from a water-containing waste having poisonous substances, comprising the steps of: (a) removing a major portion of water contained in the waste, (b) stirring the waste during the subsequent steps except for the last step, (c) drying the waste to a residual water content of about 12-13% by weight, without igniting flammable material contained in the waste, (d) microwave heating the waste to further reduce the residual water content to 0.1-5% by weight so that the waste becomes powdery, (e) cooling the waste powder to room temperature, (f) contacting the waste powder with a thermoplastic resin, (g) microwave heating the mixture of the waste powder and the thermoplastic resin at a rate which enables the resin to melt and encapsulate the waste powder particles, and (h) molding the resin encapsulated particles into an article having a desired shape.
Claim 3
Dependent Claim
13 words
A method as set forth in claim 1 wherein said waste is sludge.
Claim 4
Dependent Claim
14 words
A method as set forth in claim 2 wherein said sludge contains heavy metals.
Claim 5
Dependent Claim
14 words
A method as set forth in claim 1 wherein said thermoplastic resin is polyethylene.
Claim 6
Dependent Claim
17 words
A method as set forth in claim 1 wherein said thermoplastic resin is a waste thermoplastic resin.
Claim 7
Dependent Claim
26 words
A method as set forth in claim 1 wherein the water content of the waste is reduced to 65-70% by weight during the water removing step.
Claim 8
Dependent Claim
17 words
A method as set forth in claim 1 wherein the waste is vibrated to enhance stirring effect.
Claim 9
Dependent Claim
40 words
A method as set forth in claim 1 wherein in the case of a waste containing radioactive materials, the waste is combined with a powdery mixture of sludge and porous pearlite before it is subjected to the water removing step.
References Cited (Backward Citations)
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Cited
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Cited
US4094784A
Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-30 | 1984-06-30 | 1984-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-30 | 1988-06-30 | 1988-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-30 | 1992-06-30 | 1992-12-30 | $7700.00 | Window Closed / Lapsed |