Gradient fining tank for refining foamy molten glass and a method of using the same

Patent metadata

Field	Value
Publication number	US-11919798-B2
Application number	US-202017061806-A
Country	US
Kind code	B2
Filing date	Oct 2, 2020
Priority date	Mar 15, 2018
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

A gradient fining tank and a method of operating the tank to refine foamy molten glass is disclosed. The gradient fining tank includes a floor, a roof, and two laterally-spaced sidewalls that at least partially define an interior chamber of the tank. The floor of the tank is profiled to provide the tank with an extended shallow portion that defines an inlet to the interior chamber and a deep holding portion that defines an outlet from the interior chamber. An entry section of the floor provides the extended shallow portion of the tank and a transition section and exit section of the floor provide the deep holding portion. A depth of the interior chamber at an outlet end of the deep holding portion is greater than a depth of the interior chamber at the outlet end of the extended shallow portion.

First claim

The invention claimed is:

1. A gradient fining tank for refining foamy molten glass, the gradient fining tank comprising:
a roof, a floor, and a pair of sidewalls that connect the roof and floor, the roof, floor, and sidewalls at least partially defining an interior chamber for holding a molten glass bath, the floor having an entry section that includes a flow surface, an exit section that includes a flow surface, and a transition section that extends downwardly and outwardly from the entry section of the floor to the exit section of the floor, the transition section of the floor having a flow surface that slopes downwardly and outwardly from the flow surface of the entry section of the floor;
an inlet that communicates with an upstream portion of the interior chamber defined by an extended shallow portion of the gradient fining tank that includes the entry section of the floor, the extended shallow portion of the gradient fining tank having an inlet end and an outlet end;
an outlet that communicates with a downstream portion of the interior chamber defined by a deep holding portion of the gradient fining tank that includes the transition section and the exit section of the floor, the deep holding portion of the gradient fining tank having an inlet end that communicates with the outlet end of the extended shallow portion and an outlet end, wherein a depth of the downstream portion of the interior chamber at the outlet end of the deep holding portion is greater than a depth of the upstream portion of the interior chamber at the outlet end of the extended shallow portion, and wherein the outlet of the gradient fining tank is downwardly displaced from the inlet of the gradient fining tank; and
a skimmer that extends downwardly from the roof of the gradient fining tank so that a free end of the skimmer cooperates with the transition section of the floor and the sidewalls to define a restricted passage.

2. The gradient fining tank set forth in claim 1 , wherein the flow surface of the transition section slopes downwardly to the flow surface of the exit section such that a depth of the downstream portion of the interior chamber progressively increases along the transition section.

3. The gradient fining tank set forth in claim 1 , wherein the flow surface of the transition section of the floor is an upper flow surface that slopes downwardly to an intermediate step flow surface of the transition section, and wherein the transition section further includes a lower flow surface that slopes downwardly from the intermediate step flow surface to the flow surface of the exit section.

4. The gradient fining tank set forth in claim 1 , wherein the skimmer is one of a plurality of skimmers that extend downwardly from the roof of the gradient fining tank.

5. The gradient fining tank set forth in claim 1 , further comprising one or more heating devices.

6. The gradient fining tank set forth in claim 5 , wherein the one or more heating devices includes one or more impingement burners mounted in the roof of the gradient fining tank within the extended shallow portion of the tank.

7. The gradient fining tank set forth in claim 5 , wherein the one or more heating devices includes one or more impingement burners mounted in one or both of the sidewalls within the extended shallow portion of the tank.

8. The gradient fining tank set forth in claim 1 , wherein the inlet is further configured to receive a flow of molten glass falling from a submerged combustion melter.

9. The gradient fining tank set forth in claim 1 , wherein a molten glass bath is held within the interior chamber of the fining tank and contained within the extended shallow portion and the deep holding portion of the fining tank has a surface level that is constant in the upstream and downstream portions of the interior chamber, the molten glass bath further having a density that increases along the floor of the fining tank in a flow direction through the interior chamber as well as from the surface level of the molten glass bath towards the floor of the fining tank.

10. The gradient fining tank set forth in claim 9 , wherein a higher-density phase of the molten glass bath has a density that range from above 1.0 gm/cm 3 to 1.5 gm/cm 3 and a lower-density phase of the molten glass bath has a density that ranges from 0.7 gm/cm 3 to 1.0 gm/cm 3 , within the extended shallow portion of the gradient fining tank.

11. The gradient fining tank set forth in claim 1 , wherein the flow surface of the transition section slopes downwardly from the flow surface of the entry section of the floor at an angle that ranges from 30° to 75° from a horizontal imaginary plane extending from a downstream end of the flow surface of the entry section.

12. The gradient fining tank set forth in claim 11 , wherein the flow surface of the transition section slopes downwardly to the flow surface of the exit section such that a depth of the downstream portion of the interior chamber progressively increases along the transition section, and wherein the flow surface of the exit section of the floor extends outwardly from the flow surface of the transition section of the floor at an angle that ranges from 115° to 160°.

13. A gradient fining tank for refining foamy molten glass, the gradient fining tank comprising:
a roof, a floor, a front end wall, and a pair of sidewalls that connect the roof and floor, the roof, floor, the front end wall, and sidewalls at least partially defining an interior chamber for holding a molten glass bath, the floor having an entry section that includes a flow surface, an exit section that includes a flow surface, and a transition section that extends downwardly and outwardly from the entry section of the floor to the exit section of the floor, the transition section of the floor having a flow surface that slopes downwardly and outwardly from the flow surface of the entry section of the floor, wherein the flow surface of the transition section slopes continuously obliquely downwardly to an intersection of the flow surface of the transition section and the flow surface of the exit section such that a depth of the downstream portion of the interior chamber progressively increases along the transition section;
an inlet in the roof or in the front end wall or in one or both of the sidewalls that communicates with an upstream portion of the interior chamber defined by an extended shallow portion of the gradient fining tank that includes the entry section of the floor, the extended shallow portion of the gradient fining tank having an inlet end adjacent to the front end wall and an outlet end; and
an outlet that communicates with a downstream portion of the interior chamber defined by a deep holding portion of the gradient fining tank that includes the transition section and the exit section of the floor, the deep holding portion of the gradient fining tank having an inlet end that communicates with the outlet end of the extended shallow portion and an outlet end, wherein a depth of the downstream portion of the interior chamber at the outlet end of the deep holding portion is greater than a depth of the upstream portion of the interior chamber at the outlet end of the extended shallow portion, and wherein the outlet of the gradient fining tank is downwardly displaced from the inlet of the gradient fining tank.

14. A gradient fining tank for refining foamy molten glass, the gradient fining tank comprising:
a roof, a floor, a front end wall, and a pair of sidewalls that connect the roof and floor, the roof, floor, the front end wall, and sidewalls at least partially defining an interior chamber for holding a molten glass

Assignees

• Owens Brockway Glass Container

Inventors

• Wang Zhongming
• Vempati Udaya K
• Lin Ya-Cheng

Classifications

• C03B5/207 Primary

  Foraminous or mesh screens, e.g. submerged sieves · CPC title

• C03B5/03

  Tank furnaces · CPC title

• C03B5/04

  in tank furnaces {(C03B5/02 takes precedence)} · CPC title

• C03B5/205

  Mechanical means for skimming or scraping the melt surface · CPC title

• C03B5/225 Primary

  Refining (C03B5/18 takes precedence {; Refining agents C03C1/004}) · CPC title