US3879856A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for drying particulate materials
Assignee: BARR & MURPHY OVERSEAS Ltd A BRITISH Co
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Filing: 1974-01-30
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Granted: 1975-04-29
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Expires: 1994-01-30
Abstract
Abstract Material can be dried using gas of temperature higher than a critical temperature of the material, such as softening point, by circulating the material in gas through a circuit. At a point in the circuit is a zone to an inner region of which the hot air is introduced, while circulated gas and material is introduced into an outer region. Drying occurs as the gases in the regions intermingle without the material reaching the the critical temperature. In apparatus of the invention the intermixing occurs in a manifold with inlets such that the gases assume vortical motion.
Inventors
- 👤 Peter Joachim Barr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:41
CPC Classifications
F; F26; F26B; F26B17/00; F26B17/10; F26B17/107
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
249 words
A method of drying particulate material comprising the steps of: passing a main stream of gas around a closed path which includes a circular cross-sectioned drying zone; introducing moist particulate material into the gas stream at a point outside said drying zone; introducing said main stream of gas including said moist particulate material into said drying zone at an inlet position close to one end thereof in a direction substantially tangential to the axis of said zone whereby a substantially helical stream of relatively cool gas in the region of the periphery of said zone is established; introducing a stream of gas at a higher temperature than said main stream of gas into said zone substantially along the axis of said zone at the same end of said zone as the inlet of the main stream of gas so that contact is established between the hot axial gas stream and the relatively cool helical main gas stream carrying moist particulate matter; withdrawing all of the gas from the drying zone through an outlet at the opposite end of said drying zone from the inlet in a direction substantially tangential to the axis of said drying zone; dividing the gas withdrawn from the drying zone through the outlet into a main moist particle carrying stream and a dry particle carrying stream; recirculating the gas in said moist particle carrying stream to the inlet of said drying zone; and separating and discharging the dry particles from said dry particle carrying stream.
Claim 2
Independent Claim
249 words
A method of drying particulate material comprising the steps of: passing a main stream of gas around a closed path which includes a circular cross-sectioned drying zone; introducing moist particulate material into the gas stream at a point outside said drying zone; introducing said main stream of gas including said moist particulate material into said drying zone at an inlet position close to one end thereof in a direction substantially tangential to the axis of said zone whereby a substantially helical stream of relatively cool gas in the region of the periphery of said zone is established; introducing a stream of gas at a higher temperature than said main stream of gas into said zone substantially along the axis of said zone at the same end of said zone as the inlet of the main stream of gas so that contact is established between the hot axial gas stream and the relatively cool helical main gas stream carrying moist particulate matter; withdrawing all of the gas from the drying zone through an outlet at the opposite end of said drying zone from the inlet in a direction substantially tangential to the axis of said drying zone; dividing the gas withdrawn from the drying zone through the outlet into a main moist particle carrying stream and a dry particle carrying stream; recirculating the gas in said moist particle carrying stream to the inlet of said drying zone; and separating and discharging the dry particles from said dry particle carrying stream.
Claim 3
Dependent Claim
31 words
A method as claimed in claim 1 further comprising the step of imparting an initial vortical motion to the hot gas prior to its entry into said circular section drying zone.
Claim 4
Dependent Claim
84 words
A method as claimed in claim 1 in which the main gas stream is introduced into the drying zone at a temperature below the melting point of the particulate material; and the hot gas stream is introduced into the drying zone at a temperature above the melting point of the particular material, the hot gas stream in proportion to the main gas stream so that the temperaturE of the gas stream leaving the drying zone is below the melting point of the particulate material.
Claim 5
Independent Claim
217 words
An apparatus for drying particulate material suspended in a stream of gas comprising: a circular-cross-section manifold having a first gas inlet at one end thereof entering said manifold along the axis of said manifold, a second gas inlet through the side of said manifold at the end of said manifold near said first inlet offset from the axis of said manifold and positioned to direct a stream of gas around the inside periphery of said manifold, and an outlet through the side of said manifold and at the end of said manifold opposite said second inlet also offset from the axis of said manifold; hot gas supply means connected to said first gas inlet for supplying hot gas to said manifold; connecting means connecting said outlet to said second inlet to the manifold; gas circulating means for maintaining the flow of gas throughout the apparatus located in said connecting means; introduction means for introducing the moist particulate matter to be dried into the gas flowing through said connecting means, said introduction means located in said connecting means between said gas circulating means and said second inlet to the manifold; and exhaust means for removing the spent gas and dried material, said exhaust means located in said connecting means between said manifold outlet and said gas circulating means.
Claim 6
Independent Claim
217 words
An apparatus for drying particulate material suspended in a stream of gas comprising: a circular-cross-section manifold having a first gas inlet at one end thereof entering said manifold along the axis of said manifold, a second gas inlet through the side of said manifold at the end of said manifold near said first inlet offset from the axis of said manifold and positioned to direct a stream of gas around the inside periphery of said manifold, and an outlet through the side of said manifold and at the end of said manifold opposite said second inlet also offset from the axis of said manifold; hot gas supply means connected to said first gas inlet for supplying hot gas to said manifold; connecting means connecting said outlet to said second inlet to the manifold; gas circulating means for maintaining the flow of gas throughout the apparatus located in said connecting means; introduction means for introducing the moist particulate matter to be dried into the gas flowing through said connecting means, said introduction means located in said connecting means between said gas circulating means and said second inlet to the manifold; and exhaust means for removing the spent gas and dried material, said exhaust means located in said connecting means between said manifold outlet and said gas circulating means.
Claim 7
Dependent Claim
17 words
An apparatus as claimed in claim 4 wherein said second inlet to said manifold is tangential thereto.
Claim 8
Dependent Claim
12 words
An apparatus as claimed in claim 4 wherein said manifold is conical.
Claim 9
Dependent Claim
12 words
An apparatus as claimed in claim 4 wherein said manifold is cylindrical.
Claim 10
Dependent Claim
28 words
An apparatus as claimed in claim 4 further comprising motion imparting means located in said first inlet for imparting vortical motion to said hot gas entering said manifold.
Claim 11
Dependent Claim
17 words
An apparatus as claimed in claim 8 wherein said motion imparting means is comprised of fixed vanes.
Claim 12
Dependent Claim
16 words
An apparatus as claimed in claim 4 wherein said outlet from said manifold is tangential thereto.
Claim 13
Dependent Claim
50 words
An apparatus as claimed in claim 10 further comprising baffle means in said outlet parallel to the axis of said manifold and dividing said outlet into first and second parts for respectively receiving dried material and spent gas in one part and material to be recirculated in the other part.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |