Device for controlled feeding an electrolytic cell for producing aluminum (variants)

Abstract

The invention relates to nonferrous metallurgy, in particular to the electrolytic production of aluminum, namely to the devices for feeding electrolytic cells, and can be used to feed alumina, aluminum fluoride, crushed electrolyte to electrolytic cells for producing aluminum. A device for feeding an electrolytic cell for producing aluminum comprises a hopper, a metering chamber with loading windows located around a perimeter of an upper part of the metering chamber above the hopper base, a valve stem with a pneumatic actuator, an upper locking element rigidly fixed to the valve stem at the upper part of the metering chamber, wherein the upper locking element is positioned between upper and lower edges of loading windows, when the stem is in an upper position, and a lower locking element is mounted on an end of the valve stem. According to a first variant of the present invention, the device is characterized in that at least one metering shuttle valve is provided in the upper part of the metering chamber above the upper locking element, and the metering shuttle valve is rigidly fixed to the valve stem so that its upper end in an initial position of the valve stem is located below the upper edge of the loading windows. According to a second variant of the present invention, the device is characterized in that, inside the hopper above the upper locking element, the device comprises at least one circular rib fixed into the upper part of the metering chamber, at least one rib and at least one baffle plate are fixed to the hopper walls so that the material can pass through gaps between plate ends and the walls of the hopper and the metering chamber. The invention provides for the better stability of feeding and may improve processing performance of an electrolytic cell.

Claims

1. A device for feeding an electrolytic cell for producing aluminum comprising: a hopper for receiving a feeding material; a metering chamber with loading windows located around a perimeter of an upper part of the metering chamber above a hopper base; a stem with a pneumatic actuator; an upper locking element rigidly fixed to the stem in the upper part of the metering chamber, wherein the upper locking element is positioned between upper and lower edges of the loading windows, when the stem is in an upper position; and a lower locking element fixed on an end of the stem, wherein at least one circular rib is fixed on the upper part of the metering chamber above the upper locking element so that the feeding material can pass through gaps between an end of the at least one circular rib and walls of the hopper; and at least one second rib is fixed to the hopper walls so that the feeding material can pass through gaps between an end of the second rib and the metering chamber, characterized in that the device comprises at least one baffle plate having two ends fixed to the hopper walls so that the feeding material can pass through gaps between the ends of the baffle plate and the at least one circular rib and the at least one second rib and between the ends of the baffle plate and the hopper walls and the upper part of the metering chamber, wherein the at least one circular rib and the at least one second rib are at an angle from between 40° to 90° to the metering chamber.

2. The device according to claim 1, characterized in that the at least one baffle plate fixed to the hopper walls is configured as a truncated cone or truncated pyramid.

3. The device according to claim 1, characterized in that the at least one baffle plate fixed on the hopper walls is fixed on the walls at an angle of −45° to 90° or from 90° to +45°.

4. The device according to claim 1, characterized in that the metering chamber is made of a pipe having a square, rectangular, hexagonal, or triangular cross-section.

5. The device according to claim 1, wherein the at least one baffle plate is fixed to the hopper walls with at least one vertical rib.

6. The device according to claim 1, wherein the metering chamber further comprises at least one vertical rib in the loading windows, the rib being radially directed toward the hopper walls.

Description

(1) The nature of the invention, however, will best be understood when described in connection with the accompanying drawings, in which.

(2) FIGS. 1 and 2 are section views illustrating the devices for feeding an electrolytic cell for producing aluminum according to first and second variants of the present invention respectively;

(3) FIGS. 3-7 are section views illustrating embodiments of the metering shuttle valve;

(4) FIGS. 8-10 are section views illustrating embodiments of the baffle plate.

(5) The feeding device comprises hopper 1, pneumatic cylinder 2, and metering chamber 3. A lower part 4 of metering chamber 3 is located under loading windows 5 under an outlet in the bottom of hopper 1. An upper part of metering chamber 3 as well as loading windows 5 are located in the lower part of hopper 1. Inside the metering chamber is located a valve stem 6 actuated by a pneumatic cylinder 2. To a lower end of valve stem 6 is attached a lower locking element 7; in an upper part of metering chamber, an upper locking element 8 and a metering shuttle valve 9 located below the element are rigidly fixed to the valve stem 6. Metering chamber 3 has a flange 10 that is fixed under loading windows 5 and rests upon a bottom of the hopper 1.

(6) According to the second variant of the invention, unlike the first one, inside hopper 1 above the upper locking element 8 is a circular rib 11 fixed to the outer side of the upper part of metering chamber 3, and a baffle plate 12, wherein a material can pass through gaps between ends of the baffle plate 12 and the walls of hopper 1 and metering chamber 3. Baffle plate 12 is fixed to the wall of hopper 1 by means of vertical ribs 13. However, instead of ribs 13 pins may be used. Above the baffle plate 12 ribs 14 are fixed to the walls of hopper 1. To ensure rigidity, the loading windows 5 of metering chamber 3 have vertical ribs 15 connected to support flange 10.

(7) FIGS. 3-7 are section views illustrating metering shuttle valve 8 respectively shaped as a washer 18 with openings 19 along its perimeter, as a hollow truncated cone 20, as a sleeve 21, as a hollow cylinder 22 mounted on the valve stem 6 by means of vertical ribs 23 and hub 24, and as a ring 25 connected by pins 26 to hub 24.

(8) FIGS. 8-10 are section views illustrating a baffle plate shaped respectively as a washer 27, as a truncated cone 28, and as a truncated pyramid 29 coaxial to the metering chamber. FIG. 2 is a section view illustrating a flat-shaped baffle plate 12.

(9) The devices for feeding electrolytic cells function as follows:

(10) The feeding materials continuously fill the space in the zone of loading window 5 in metering chamber 3. In an initial position, valve stem 6 is in its upper position, upper locking element 8 is located between the upper and lower edges of the loading windows 5, and the outlet in the bottom of metering chamber 4 is closed by locking element 7. The material in the bottom of hopper 1 fills the lower part of metering chamber 4 through loading windows 5. To unload metering chamber 4 a control signal goes to pneumatic cylinder 2 that moves downward valve stem 6 with upper and lower locking elements 8 and 7 and metering shuttle valve 9. At this, the passage under loading windows 5 in lower part 4 of metering chamber 3 is blocked by locking element 7 and the loose materials go through the outlet in the bottom of metering chamber 4, and then through a chute into a well in the alumina-electrolyte crust. After emptying metering chamber 4, valve stem 6 makes a backstroke and returns to its initial position. At that, lower locking element 7 blocks the outlet of the metering chamber, upper locking element 8 fully opens a passageway for the material under locking element 8 through loading windows 5 in metering chamber 4.

(11) In the device according to the first variant of the present invention (see FIG. 1), valve stem 6 makes a reciprocal motion from one extreme position to another, and the materials above the upper locking element 8 are impacted by metering shuttle valve 9, which crushes lumps and bridges, and forces the materials to loading windows 5. This ensures an uninterrupted supply of the materials to the loading windows and filling metering chamber 4, and facilitates stabilization of the electrolytic cell feeding.

(12) In the device according to the second variant of the present invention (see FIG. 2), circular ribs 11, baffle plate 12, and ribs 14 prevent the gravitational pressure from the upper layers onto the materials under plate 12, thereby excluding compaction and changes in flowing ability in the entire volume of the lower part of hopper 1, regardless the fluctuations of the fill level in hopper 1, thereby providing a continuous and repetitive filling of metering chamber 4 and a stable feeding of an electrolytic cell. The materials discharged from the lower part of hopper 1 are replenished with the materials from above baffle plate 12, the new materials enter through the gaps between plate 12 and the walls of the hopper 1 and metering chamber 3.

(13) The device according to the present invention provides for the better stability of feeding and may improve processing performance of an electrolytic cell. The efficiency of the technical solutions is confirmed by testing prototypes of the device on operating electrolytic cells.