CA1050267A - Apparatus for recovery of metallic zinc from dross - Google Patents
Apparatus for recovery of metallic zinc from drossInfo
- Publication number
- CA1050267A CA1050267A CA225,635A CA225635A CA1050267A CA 1050267 A CA1050267 A CA 1050267A CA 225635 A CA225635 A CA 225635A CA 1050267 A CA1050267 A CA 1050267A
- Authority
- CA
- Canada
- Prior art keywords
- dross
- container
- zinc
- metallic zinc
- set forth
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Manufacture And Refinement Of Metals (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An apparatus for separating and recovering metallic zinc from an ash-like solid substance composed of a mixture of metallic zinc, zinc oxide and other zinc containing materials is disclosed. This apparatus comprises a saucer-like container of an inverse cone form for receiving dross and a plurality of agitating scraper plates disposed in said container to squeeze out metallic zinc from the dross, discharge means for metallic zinc and discharge means for secondary dross being mounted on an opening formed on the bottom of said cylinder.
An apparatus for separating and recovering metallic zinc from an ash-like solid substance composed of a mixture of metallic zinc, zinc oxide and other zinc containing materials is disclosed. This apparatus comprises a saucer-like container of an inverse cone form for receiving dross and a plurality of agitating scraper plates disposed in said container to squeeze out metallic zinc from the dross, discharge means for metallic zinc and discharge means for secondary dross being mounted on an opening formed on the bottom of said cylinder.
Description
-' 1050Z67 APPARATUS FOR RECOVERY OF METALLIC ZINC FROM DROSS
Abstract of the Disclosure:
An apparatus for separating and recovering metallic ~-~
zinc from an ash-like solid substance composed of a mixture of metallic zinc, zinc oxide and other zinc containing mater-ials is disclosed. This apparatus comprises a saucer-like - -container of an inverse cone form for receiving dross and a plurality of agitating scraper plates disposed in said con-tainer to squeeze out metallic zinc from the dross, discharge -means for metallic zinc and discharge means for secondary -dross being mounted on an opening formed on the bottom of said cylinder.
Background of the Invention:
This invention relates to an apparatus for separat-ing and recovering metallic zinc from an ash-like solid sub-stance composed of a mixture of metallic zinc, zinc oxide and other zinc containing materials.
Zinc is an easily-oxidizable metal, and hence, a molten zinc bath in a melting furnace or the like has the sur-face covered with oxides. ~urther, this surface layer of oxide entang~les therein a large amount of metallic zinc and its fluidity is very low. Accordingly, this surface layer of oxide generally is in the form of a hard and thick layer.
For this reason, there is customarily adopted an operation of scattering a flux, generally a flux of the chloride type, ~ -on the surface of a molten zinc bath, separating and recover-ing metallic zinc involved in the oxide layer by manual agit-ation. By this operation, the fluidity of the oxide layer is - ~.
., .
~050267 increased and the majority of metallic zinc involved in the oxide layer is recovered into the zinc bath. However, a considerable amount of metallic zinc is still contained in the oxide layer mainly in the form of fine particles. This amount of residual zinc differs greatly depending on the configuration of the surface state of starting materials to be melted or on the fluxing method. For example, in the case of a starting material having a large surface area such as zinc sheets deposited in the elctrolysis the amount of such residual zinc is as large as 1 to 4% by~weight based on the starting material. In case such mixture composed of zinc and its oxide (hereinafter referred to as "dross") is treat-ed in the zinc refining process, considerable processing expenses are required for this treatment. Therefore, various methods have heretofore been practised to squeeze out the metal from the dross and thereby obtain a final product di-rectly from the dross.
The conventional methods comprise charging into a vessel having an inclined bottom face dross scraped out of a melting furnace, agitating the dross manually by means of an iron rod provided with scrape plates and thus squeezing out metallic zinc from the dross. According to this method, just before or during the operation a flux or zinc dust is sometimes added to utilize the heat generated by the oxida-tion reaction. In this method, however, since agitation isperformed manually, no uniform agitation can be attained and further,~because of the individual metallic zinc particles ; having the surface covered with a thin oxide layer, the heat resulting from reac~ion with the flux can not be utilized effectively. Therefore, the metal recovery ratio is rela-~ ~ - ... .. . . , - . .
;: . ... ~ . . ..
- 1050267 `
tively low, for example about 40% by weight. Further, con-siderable labors are required for practice of this method.
As another conventional method, there can be men-tioned a method for obtaining crude zinc by melt-extracting a zinc-containing material such as dross, hard zinc and zinc die-cast alloy scrap with use of a rotary furnace.
This method is characterized in that a variety of starting materials including the above-mentioned, ash-like dross, scrap metal and chipped metal masses can be treated. Fur-ther, in this method, since a high agitation effect can be attained, there is obtained an advantage that the metal re- -covery ratio is increased. However, the apparatus used is a rotary furnace having a complicated structure and a large size, and since the ratio of filling of the starting mater-ial into the furnace is 10 to 40% at most and a large quan-t~ty of heat escapes from the furnace, the furnace should be heated directly or indirectly even when hot dross coming from a zinc melting furnace is treated. Moreover, when the ash-like dross is treated, a considerable amount of dusts is carried over from the furnace with its rotation and met-allic zinc is partially oxidized and further, since chlorine compounds are contained in such dusts, they are deposited and fixed in ducts of a dust precipitator, resulting in blocking up of a gas passage.
Summary of the Invention:
It is therefore a primary object of this invention to provide a compact apparatus for recovery of metallic zinc from dross in which the filling ratio of dross is increased and metallic zinc is effectively squeezed out from the dross without external supply of heat and use of a flux.
Thus, in accordance with the present teachings, an apparatus is provided for recovering metallic zinc in dross discharged from a zinc melting furnace. The apparatus comprises a saucer-like container for receiving dross, the container having a bottom portion of an inverse conical form inclined downwardly and a plurality of agitating scraper plates supported around a vertical rotary shaft in the container to squeeze out metallic zinc from the dross.
Discharge means is provided for the metallic zinc and is mounted on an opening formed on the bottom of the container.
The discharge comprisies a rotor which is attached to the lower end portion of the rotary shaft and is adapted to rotate with rotation of the rotary shaft. A hollow cylinder is provided in a manner that its upper portion is brought into linear contact with the bottom portion of the rotor to form a slight aperture therebetween.
Brief Description of the Drawings:
Fig. 1 is a diagram showing the longitudinal sec-tion of an embodiment of the metallic zinc recovery apparatus of this invention.
Fig. 2 is a diagram showing the section taken along the line A-A' in Fig. 1.
Detailed Description of the Invention:
The apparatus of this invention can be attached easily at an appropriate position in the proximity of a zinc melting furnace. When the apparatus of this invention is employed, it is unnecessary to add a heat generating material, e.g. a flux or supply heat from the outside during the oper-ation of recovering metallic zinc from dross. In other words, the intended recovery can be accomplished mechanically by J~3 ~ _ 4 _ - lOSQZ67 utilizing only the heat of the dross per se.
An embodiment of the apparatus of this invention will ;now be described by reference to the accompanying drawings.
~ .
- 4a -~OS(~Z67 Referring to Fig. l, a saucer-like container 1 composed of a steel plate is disposed to receive dross scraped out from a melting furnace, and the bottom portion of the con-tainer has an inverse conical form with such a gradual in-clination angle that fine streams or liquid drops of moltenmetal squeezed out from the dross are collected to a central opening 2 along the inclined face of the container l. The outer periphery of the container l is covered with a heat in-sulating material ll so that escape of heat from the container is prevented.
A plurality of scrape plates 9 composed of a special steel or heat-resistant porcelain are fitted around a rotary shaft 7 in the container l to agitate dross and squeeze out molten zinc from the dross. A rotor 12 composed of graphite which rotates together with the rotary shaft 7 is attached to the end of the rotary shaft 7 to separate and recover the squeezed out molten zinc from the dross.
A hollow cylinder 3 composed of a heat-resistant, anti-corrosive material such as graphite and heat-resistant mortar is disposed at the opening 2 perforated through the center of the conical bottom of the container l as the dis-charge means for secondary dross, and this hollow cylinder 3 is supported by a supporting plate 4. One end of this sup-porting member 4 is pivoted on a fulcrum 13 and the other end is fixed by a gut 6. The upper portion of the cylinder 3 takes a conical form with an inclination angle almost equal *c that of the bottom portion of the container 1 and it has an almost linear contact with the lower peripheral edge ~
the rotor 12 to form a slight aperture therebetween as shown in Fig. 1. When such discharge mechanism is adopted, molten ~050Z67 zinc having a large specific gravity and a good fluidity is withdrawn from a hole 5 through the slight aperture of this line!ar contact area while rotating the rotor 12 and fall into a casting mold (not shown) disposed below. On the other S hancl, the secondary dross is not allowed to pass through this slight aperture but is retained in the container 1. When squeezing out of metallic zinc is completed, the gut 6 at-tached to the supporting member 4 is dismounted, and a lower rail including the cylinder 3 and supporting member 4 is ro-tated around the fulcrum 13 to discharge the secondary drossconsisting mainly of the oxides.
Details of the apparatus of this invention having the above principal structure and procedures of operation of the apparatus will now be described.
A considerable clearance is formed between the wall of the container and the scraper plate 9 and the dross is coated on this clearance as indicated by referential nu-meral 14 in Fig. 1, whereby the wall of the container (steel plate) can be prevented from corrosion because of not coming into contact with the molten zinc and further, the tempera-ture of the dross to be treated can be maintained. As fur-ther means for maintaining the temperature for operation, when the operation of the apparatus is interrupted, there is adopted a method in which the hot secondary dross from which molten zinc has been squeezed out is not discharged but left in the container and it is first discharged when the subse-quent dross treatment is initiated.
According to a preferred example of the manner for attaching scraper plates g, four arms 8 are rectangularly fixed to the rotary shaft 7 so that they are spaced from one another by an angle of 90 and two each ( 8 in total ) of the plates 9 are fitted to respective arms 8 by means of set boards 10. In order to enhance the squeezing effect, it is preferred that each scraper plate 9 be inclined with respect to the arm by an angle of 45 so that when the rotary shaft 7 is rotated in the clockwise direction ( in the direction indicated by an arrow in Fig. 2 ), the scraper plate 9 has -functions of scraping up the dross along the inclined face of the conical bottom portion of the container and thus squeezing out metallic zinc. Further, in order to collect squeezed out zinc conveniently, it is preferred that the low-er side of the scraper plate 9 be substantially parallel to the inclined face of the bottom portion of the container as shown in Fig. l. The number of arms, and the size and num-ber of scraper plates attached to each arm are appropriately determined and changed depending on the size of the squeezing apparatus, and these elements are not particularly critical in this invention.
The shaft 7 may be rotated in one fixed direciton.
In this case, however, if a void portion corresponding to the passage of the scraper plate is formed in the dross, the agitating and squeezing effects are reduced. According-ly, it is preferred that the direction of rotation of the rotary shaft be changed to an oppos~ di~rection at every prescribed interval.
Another advantage of the apparatus of this invention is that the filling ratio of dross is as high as more than 90%, which results in diminution of the size of the appara-tus and increase of the tempera~ure-maintaining effect. Fur-ther, since the rotation frequency of the scraper plates is 10 to 20 rotations at highest per minute, generation of dusts ~050267 can be greatly reduced. Moreover, the upper portion of the container is isolated from the outer environment by means of :
a lid 15 having a dross feed opening and an exhaust opening connected to a dust precipitator 16. Accordingly, good work-ing condition can be maintained in the working environment. `
If a sliding system is adopted so that the lower rail com-prising members 3, 4, 6 and 13 shown in Fig. 1 is fixed at :`
an optional position by means of set boards, the aperture of the linear contact area through which the molten zinc is withdrawn can easily be adjusted even when it is broadened due to long-time operation of the apparatus.
This invention will now be illustrated in detail by reference to the following Example showing the treatment of dross using the apparatus of this invention as shown in Figs.
1 and 2.
Example 1 --An apparatus comprising as a dross container a sau-cer-like cylinder having a diameter of about 1 m, the length of the side wall in the vertical position being 30 cm and the inclination angle of the bottom portion of an inverse conical form being about 20, and 8 agitating scraper plates disposed and arranged as in Figs. 1 and 2, was located in the proximity of a melting furnace for deposited zinc plates from the zinc electrolysis. The dross treatment was conducted under the conditions shown in Table 1 to obtain results shown in Table 1.
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~` ~osoz67 As is seen from the results shown in the above Table 1, when the apparatus of this invention is used for the dross treatment, about 90~ of metallic zinc contained - :~
in the dross can be recovered and formed into a final pro-S duct without supplying heat from the outside.
Abstract of the Disclosure:
An apparatus for separating and recovering metallic ~-~
zinc from an ash-like solid substance composed of a mixture of metallic zinc, zinc oxide and other zinc containing mater-ials is disclosed. This apparatus comprises a saucer-like - -container of an inverse cone form for receiving dross and a plurality of agitating scraper plates disposed in said con-tainer to squeeze out metallic zinc from the dross, discharge -means for metallic zinc and discharge means for secondary -dross being mounted on an opening formed on the bottom of said cylinder.
Background of the Invention:
This invention relates to an apparatus for separat-ing and recovering metallic zinc from an ash-like solid sub-stance composed of a mixture of metallic zinc, zinc oxide and other zinc containing materials.
Zinc is an easily-oxidizable metal, and hence, a molten zinc bath in a melting furnace or the like has the sur-face covered with oxides. ~urther, this surface layer of oxide entang~les therein a large amount of metallic zinc and its fluidity is very low. Accordingly, this surface layer of oxide generally is in the form of a hard and thick layer.
For this reason, there is customarily adopted an operation of scattering a flux, generally a flux of the chloride type, ~ -on the surface of a molten zinc bath, separating and recover-ing metallic zinc involved in the oxide layer by manual agit-ation. By this operation, the fluidity of the oxide layer is - ~.
., .
~050267 increased and the majority of metallic zinc involved in the oxide layer is recovered into the zinc bath. However, a considerable amount of metallic zinc is still contained in the oxide layer mainly in the form of fine particles. This amount of residual zinc differs greatly depending on the configuration of the surface state of starting materials to be melted or on the fluxing method. For example, in the case of a starting material having a large surface area such as zinc sheets deposited in the elctrolysis the amount of such residual zinc is as large as 1 to 4% by~weight based on the starting material. In case such mixture composed of zinc and its oxide (hereinafter referred to as "dross") is treat-ed in the zinc refining process, considerable processing expenses are required for this treatment. Therefore, various methods have heretofore been practised to squeeze out the metal from the dross and thereby obtain a final product di-rectly from the dross.
The conventional methods comprise charging into a vessel having an inclined bottom face dross scraped out of a melting furnace, agitating the dross manually by means of an iron rod provided with scrape plates and thus squeezing out metallic zinc from the dross. According to this method, just before or during the operation a flux or zinc dust is sometimes added to utilize the heat generated by the oxida-tion reaction. In this method, however, since agitation isperformed manually, no uniform agitation can be attained and further,~because of the individual metallic zinc particles ; having the surface covered with a thin oxide layer, the heat resulting from reac~ion with the flux can not be utilized effectively. Therefore, the metal recovery ratio is rela-~ ~ - ... .. . . , - . .
;: . ... ~ . . ..
- 1050267 `
tively low, for example about 40% by weight. Further, con-siderable labors are required for practice of this method.
As another conventional method, there can be men-tioned a method for obtaining crude zinc by melt-extracting a zinc-containing material such as dross, hard zinc and zinc die-cast alloy scrap with use of a rotary furnace.
This method is characterized in that a variety of starting materials including the above-mentioned, ash-like dross, scrap metal and chipped metal masses can be treated. Fur-ther, in this method, since a high agitation effect can be attained, there is obtained an advantage that the metal re- -covery ratio is increased. However, the apparatus used is a rotary furnace having a complicated structure and a large size, and since the ratio of filling of the starting mater-ial into the furnace is 10 to 40% at most and a large quan-t~ty of heat escapes from the furnace, the furnace should be heated directly or indirectly even when hot dross coming from a zinc melting furnace is treated. Moreover, when the ash-like dross is treated, a considerable amount of dusts is carried over from the furnace with its rotation and met-allic zinc is partially oxidized and further, since chlorine compounds are contained in such dusts, they are deposited and fixed in ducts of a dust precipitator, resulting in blocking up of a gas passage.
Summary of the Invention:
It is therefore a primary object of this invention to provide a compact apparatus for recovery of metallic zinc from dross in which the filling ratio of dross is increased and metallic zinc is effectively squeezed out from the dross without external supply of heat and use of a flux.
Thus, in accordance with the present teachings, an apparatus is provided for recovering metallic zinc in dross discharged from a zinc melting furnace. The apparatus comprises a saucer-like container for receiving dross, the container having a bottom portion of an inverse conical form inclined downwardly and a plurality of agitating scraper plates supported around a vertical rotary shaft in the container to squeeze out metallic zinc from the dross.
Discharge means is provided for the metallic zinc and is mounted on an opening formed on the bottom of the container.
The discharge comprisies a rotor which is attached to the lower end portion of the rotary shaft and is adapted to rotate with rotation of the rotary shaft. A hollow cylinder is provided in a manner that its upper portion is brought into linear contact with the bottom portion of the rotor to form a slight aperture therebetween.
Brief Description of the Drawings:
Fig. 1 is a diagram showing the longitudinal sec-tion of an embodiment of the metallic zinc recovery apparatus of this invention.
Fig. 2 is a diagram showing the section taken along the line A-A' in Fig. 1.
Detailed Description of the Invention:
The apparatus of this invention can be attached easily at an appropriate position in the proximity of a zinc melting furnace. When the apparatus of this invention is employed, it is unnecessary to add a heat generating material, e.g. a flux or supply heat from the outside during the oper-ation of recovering metallic zinc from dross. In other words, the intended recovery can be accomplished mechanically by J~3 ~ _ 4 _ - lOSQZ67 utilizing only the heat of the dross per se.
An embodiment of the apparatus of this invention will ;now be described by reference to the accompanying drawings.
~ .
- 4a -~OS(~Z67 Referring to Fig. l, a saucer-like container 1 composed of a steel plate is disposed to receive dross scraped out from a melting furnace, and the bottom portion of the con-tainer has an inverse conical form with such a gradual in-clination angle that fine streams or liquid drops of moltenmetal squeezed out from the dross are collected to a central opening 2 along the inclined face of the container l. The outer periphery of the container l is covered with a heat in-sulating material ll so that escape of heat from the container is prevented.
A plurality of scrape plates 9 composed of a special steel or heat-resistant porcelain are fitted around a rotary shaft 7 in the container l to agitate dross and squeeze out molten zinc from the dross. A rotor 12 composed of graphite which rotates together with the rotary shaft 7 is attached to the end of the rotary shaft 7 to separate and recover the squeezed out molten zinc from the dross.
A hollow cylinder 3 composed of a heat-resistant, anti-corrosive material such as graphite and heat-resistant mortar is disposed at the opening 2 perforated through the center of the conical bottom of the container l as the dis-charge means for secondary dross, and this hollow cylinder 3 is supported by a supporting plate 4. One end of this sup-porting member 4 is pivoted on a fulcrum 13 and the other end is fixed by a gut 6. The upper portion of the cylinder 3 takes a conical form with an inclination angle almost equal *c that of the bottom portion of the container 1 and it has an almost linear contact with the lower peripheral edge ~
the rotor 12 to form a slight aperture therebetween as shown in Fig. 1. When such discharge mechanism is adopted, molten ~050Z67 zinc having a large specific gravity and a good fluidity is withdrawn from a hole 5 through the slight aperture of this line!ar contact area while rotating the rotor 12 and fall into a casting mold (not shown) disposed below. On the other S hancl, the secondary dross is not allowed to pass through this slight aperture but is retained in the container 1. When squeezing out of metallic zinc is completed, the gut 6 at-tached to the supporting member 4 is dismounted, and a lower rail including the cylinder 3 and supporting member 4 is ro-tated around the fulcrum 13 to discharge the secondary drossconsisting mainly of the oxides.
Details of the apparatus of this invention having the above principal structure and procedures of operation of the apparatus will now be described.
A considerable clearance is formed between the wall of the container and the scraper plate 9 and the dross is coated on this clearance as indicated by referential nu-meral 14 in Fig. 1, whereby the wall of the container (steel plate) can be prevented from corrosion because of not coming into contact with the molten zinc and further, the tempera-ture of the dross to be treated can be maintained. As fur-ther means for maintaining the temperature for operation, when the operation of the apparatus is interrupted, there is adopted a method in which the hot secondary dross from which molten zinc has been squeezed out is not discharged but left in the container and it is first discharged when the subse-quent dross treatment is initiated.
According to a preferred example of the manner for attaching scraper plates g, four arms 8 are rectangularly fixed to the rotary shaft 7 so that they are spaced from one another by an angle of 90 and two each ( 8 in total ) of the plates 9 are fitted to respective arms 8 by means of set boards 10. In order to enhance the squeezing effect, it is preferred that each scraper plate 9 be inclined with respect to the arm by an angle of 45 so that when the rotary shaft 7 is rotated in the clockwise direction ( in the direction indicated by an arrow in Fig. 2 ), the scraper plate 9 has -functions of scraping up the dross along the inclined face of the conical bottom portion of the container and thus squeezing out metallic zinc. Further, in order to collect squeezed out zinc conveniently, it is preferred that the low-er side of the scraper plate 9 be substantially parallel to the inclined face of the bottom portion of the container as shown in Fig. l. The number of arms, and the size and num-ber of scraper plates attached to each arm are appropriately determined and changed depending on the size of the squeezing apparatus, and these elements are not particularly critical in this invention.
The shaft 7 may be rotated in one fixed direciton.
In this case, however, if a void portion corresponding to the passage of the scraper plate is formed in the dross, the agitating and squeezing effects are reduced. According-ly, it is preferred that the direction of rotation of the rotary shaft be changed to an oppos~ di~rection at every prescribed interval.
Another advantage of the apparatus of this invention is that the filling ratio of dross is as high as more than 90%, which results in diminution of the size of the appara-tus and increase of the tempera~ure-maintaining effect. Fur-ther, since the rotation frequency of the scraper plates is 10 to 20 rotations at highest per minute, generation of dusts ~050267 can be greatly reduced. Moreover, the upper portion of the container is isolated from the outer environment by means of :
a lid 15 having a dross feed opening and an exhaust opening connected to a dust precipitator 16. Accordingly, good work-ing condition can be maintained in the working environment. `
If a sliding system is adopted so that the lower rail com-prising members 3, 4, 6 and 13 shown in Fig. 1 is fixed at :`
an optional position by means of set boards, the aperture of the linear contact area through which the molten zinc is withdrawn can easily be adjusted even when it is broadened due to long-time operation of the apparatus.
This invention will now be illustrated in detail by reference to the following Example showing the treatment of dross using the apparatus of this invention as shown in Figs.
1 and 2.
Example 1 --An apparatus comprising as a dross container a sau-cer-like cylinder having a diameter of about 1 m, the length of the side wall in the vertical position being 30 cm and the inclination angle of the bottom portion of an inverse conical form being about 20, and 8 agitating scraper plates disposed and arranged as in Figs. 1 and 2, was located in the proximity of a melting furnace for deposited zinc plates from the zinc electrolysis. The dross treatment was conducted under the conditions shown in Table 1 to obtain results shown in Table 1.
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~` ~osoz67 As is seen from the results shown in the above Table 1, when the apparatus of this invention is used for the dross treatment, about 90~ of metallic zinc contained - :~
in the dross can be recovered and formed into a final pro-S duct without supplying heat from the outside.
Claims (7)
1. An apparatus for recovering metallic zinc in dross discharged from a zinc melting furnace, which comprises a saucer-like container for receiving dross, said container having a bottom portion of an inverse concial form inclined downwardly, and a plurality of agitating scraper plates supported around a vertical rotary shaft in said container to squeeze out metallic zinc from the dross and discharge means for metallic zinc mounted on an opening formed on the bottom of said container, said discharge comprising a rotor attached to the lower end portion of said rotary shaft adapted to rotate with rotation of the rotary shaft and a hollow cylinder provided in a manner that its upper portion is brought into linear contact with the bottom portion of the rotor to form a slight aperture therebetween.
2. An apparatus as set forth in Claim 1 wherein said said hollow cylinder has its upper open portion of an inverse conical form having an inclination angle almost equal to that of the bottom portion of said container.
3. An apparatus as set forth in Claim 1 wherein said hollow cylinder is mounted on a supporting member, one end of which is pivoted on a fulcrum and the other end is fixed.
4. An apparatus as set forth in Claim 1 wherein a clearance sufficient to form a thick layer of dross along the wall of the container is provided between the wall of the container and each scraper plate.
5. An apparatus as set forth in Claim 1 wherein said agitating scraper plates are supported by arms fixed on said vertical rotary shaft horizontally thereto.
6. An apparatus as set forth in Claim 5 wherein each scraper plate is inclined with respect to said arm by an angle of 45° and its lower side is substantially in parallel to the inclined face of the bottom portion of the container.
7. An apparatus as set forth in Claim 5 wherein rotation of said agitating scraper plates around said vertical rotary shaft is changed to an opposite direction at prescribed intervals.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA225,635A CA1050267A (en) | 1975-04-28 | 1975-04-28 | Apparatus for recovery of metallic zinc from dross |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA225,635A CA1050267A (en) | 1975-04-28 | 1975-04-28 | Apparatus for recovery of metallic zinc from dross |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1050267A true CA1050267A (en) | 1979-03-13 |
Family
ID=4102921
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA225,635A Expired CA1050267A (en) | 1975-04-28 | 1975-04-28 | Apparatus for recovery of metallic zinc from dross |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1050267A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102181664A (en) * | 2011-05-12 | 2011-09-14 | 大庆高新区北油创业科技有限公司 | Method for recovering zinc by smelting zinc ash and smelting device for implementing method |
| CN118129463A (en) * | 2024-05-07 | 2024-06-04 | 清苑县宏达金属有限公司 | Environment-friendly energy-saving smelting furnace for zinc ingot production |
-
1975
- 1975-04-28 CA CA225,635A patent/CA1050267A/en not_active Expired
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102181664A (en) * | 2011-05-12 | 2011-09-14 | 大庆高新区北油创业科技有限公司 | Method for recovering zinc by smelting zinc ash and smelting device for implementing method |
| CN118129463A (en) * | 2024-05-07 | 2024-06-04 | 清苑县宏达金属有限公司 | Environment-friendly energy-saving smelting furnace for zinc ingot production |
| CN118129463B (en) * | 2024-05-07 | 2024-06-28 | 清苑县宏达金属有限公司 | Environment-friendly energy-saving smelting furnace for zinc ingot production |
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