CN217431099U - Alumina preparation equipment - Google Patents
Alumina preparation equipment Download PDFInfo
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- CN217431099U CN217431099U CN202221149167.0U CN202221149167U CN217431099U CN 217431099 U CN217431099 U CN 217431099U CN 202221149167 U CN202221149167 U CN 202221149167U CN 217431099 U CN217431099 U CN 217431099U
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Abstract
The utility model provides an aluminium oxide preparation equipment, aluminium oxide preparation equipment includes: the impurity removal device is provided with an alumina feeding port, a discharge port and an impurity removal liquid inlet; the filtering device is positioned at the downstream of the impurity removing device and is provided with a feeding hole, a product outlet, a cleaning water inlet and a filtrate outlet, and the feeding hole of the filtering device is communicated with a discharging hole of the impurity removing device; the filtrate tank is provided with a collecting liquid inlet and a collecting liquid outlet, the filtrate outlet of the filtering device is communicated with the collecting liquid inlet of the filtrate tank, and the collecting liquid outlet of the filtrate tank is communicated with the impurity removing liquid inlet of the impurity removing device. Through the technical scheme provided by the application, the problem of water resource waste in the preparation process of the aluminum oxide in the related technology can be solved.
Description
Technical Field
The utility model relates to an aluminium oxide preparation technical field particularly, relates to an aluminium oxide preparation equipment.
Background
At present, three methods for recovering and extracting alumina from fly ash are available, namely an acid method, an alkali method and an acid-alkali combination method. The alumina is extracted from the fly ash by adopting an acid method, and alkali metal impurities such as potassium, sodium, calcium, magnesium and the like in the fly ash can also enter the slurry while the alumina is leached by acid, so that the quality of the alumina is influenced finally.
In the related art, the alkali metal impurities in the crystalline alumina are prepared and removed by a hydrothermal method, so that alumina with low magnesium and low calcium is obtained, namely, the alumina is washed while being prepared in production equipment, however, a large amount of water is used in the washing process, and thus, the waste of water resources is caused.
SUMMERY OF THE UTILITY MODEL
The utility model provides an alumina preparation device to solve the problem of the waste of water resources in the alumina preparation process in the correlation technique.
The utility model provides an aluminium oxide preparation equipment, aluminium oxide preparation equipment includes: the impurity removal device is provided with an alumina feeding port, a discharge port and an impurity removal liquid inlet; the filtering device is positioned at the downstream of the impurity removing device and is provided with a feeding hole, a product outlet, a cleaning water inlet and a filtrate outlet, and the feeding hole of the filtering device is communicated with a discharging hole of the impurity removing device; the filtrate tank is provided with a collecting liquid inlet and a collecting liquid outlet, the filtrate outlet of the filtering device is communicated with the collecting liquid inlet of the filtrate tank, and the collecting liquid outlet of the filtrate tank is communicated with the impurity removing liquid inlet of the impurity removing device.
Further, the edulcoration device includes leaches the device and is located the pressurization hydrothermal device who leaches the low reaches of device, and the aluminium oxide charge door and the edulcoration inlet of edulcoration device set up in leaching the device, and the discharge gate of edulcoration device sets up in pressurization hydrothermal device.
Further, the leaching device comprises a plurality of settling tanks which are sequentially communicated, an alumina feeding port is arranged in the first settling tank in the flowing direction of alumina, an impurity removing liquid inlet is arranged in the last settling tank in the flowing direction of alumina, and the last settling tank in the flowing direction of alumina is communicated with the pressurized hydrothermal device.
Furthermore, each settling tank is provided with an overflow port arranged at the upper part of the settling tank, the height of the overflow ports of the settling tanks is gradually increased in the flowing direction of the alumina, and the overflow port of the next settling tank is communicated with the previous settling tank.
Further, the difference between the height of the overflow port of the latter settling tank and the height of the overflow port of the former settling tank in the flow direction of alumina is between 0.5m and 0.7 m.
Further, the impurity removing device also comprises a driving motor and a stirring paddle in driving connection with the driving motor, and the stirring paddle is arranged in the settling tank.
Further, the stirring paddle is of a double-blade propelling structure.
Further, the cross section of the settling tank is of a circular structure, and the ratio of the diameter of the settling tank to the height of the settling tank is between 0.5 and 1.
Further, two adjacent settling tanks are communicated through a feeding pipe, and a feeding pump is arranged on the feeding pipe.
Further, the filtering device comprises a flat disc filter or a tilting disc filter.
Use the technical scheme of the utility model, aluminium oxide preparation equipment includes the edulcoration device, filter equipment and filtrate groove, when using this aluminium oxide preparation equipment, send amorphous aluminium oxide into the edulcoration device through the aluminium oxide charge door of edulcoration device, utilize the alkali metal impurity in the edulcoration device detached amorphous aluminium oxide, the discharge gate of rethread edulcoration device and filter equipment's feed inlet send into filter equipment with aluminium oxide, wash and filter aluminium oxide through wasing water in filter equipment, and will wash the filtrate and send into the filtrate groove and collect, the liquid that utilizes the filtrate groove to collect sends into the alkali metal impurity who gets rid of amorphous aluminium oxide in the edulcoration device. Because the cleaning filtrate in the filtering device is utilized and sent into the impurity removing device to remove impurities from the alumina, the water resource is saved.
Drawings
The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and do not constitute a limitation on the scope of the invention. In the drawings:
fig. 1 shows a flow chart of an alumina production apparatus provided in an embodiment of the present invention;
fig. 2 shows a schematic structural view of the settling tank in fig. 1.
Wherein the figures include the following reference numerals:
10. an impurity removal device; 11. a leaching device; 111. a settling tank; 12. a pressurized hydro-thermal device; 13. a drive motor; 14. a stirring paddle;
20. a filtration device;
30. a filtrate tank;
40. a feed pipe; 41. a feeding pump.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
As shown in FIG. 1 and FIG. 2, the embodiment of the utility model provides an alumina preparation equipment, alumina preparation equipment includes edulcoration device 10, filter equipment 20 and filtrate groove 30, edulcoration device 10 has the alumina charge door, discharge gate and edulcoration inlet, filter equipment 20 is located the low reaches of edulcoration device 10, filter equipment 20 has the feed inlet, the product outlet, wash water inlet and filtrate export, filter equipment 20's feed inlet is linked together with the discharge gate of edulcoration device 10, filtrate groove 30 has the collection inlet and collects the liquid outlet, filter equipment 20's filtrate export is linked together with filtrate groove 30's collection liquid import, filtrate groove 30's collection liquid export is linked together with edulcoration inlet of edulcoration device 10.
Use the technical scheme of the utility model, aluminium oxide preparation equipment includes edulcoration device 10, filter equipment 20 and filtrate groove 30, when using this aluminium oxide preparation equipment, send amorphous aluminium oxide into edulcoration device 10 through the aluminium oxide charge door of edulcoration device 10, utilize the alkali metal impurity among the edulcoration device 10 detached amorphous aluminium oxide, the discharge gate of rethread edulcoration device 10 and filter equipment 20's feed inlet send into filter equipment 20 with aluminium oxide, wash and filter aluminium oxide through wasing water in filter equipment 20, and collect in sending into filtrate groove 30 with wasing the filtrating, the liquid that utilizes filtrate groove 30 to collect sends into the alkali metal impurity who removes amorphous aluminium oxide in the edulcoration device 10. Because the cleaning filtrate in the filtering device 20 is utilized and sent into the impurity removing device 10 to remove impurities from the aluminum oxide, the water resource is saved.
In this embodiment, the source of the cleaning water in the filtering device 20 is condensed water generated in the acid process alumina evaporation crystallization process, so that further cyclic utilization of water resources is realized, the purpose of saving water resources is achieved, and the amount of discharged wastewater is also reduced.
It should be noted that the alumina is crystalline alumina before entering the pre-process of the impurity removal device 10, and the crystalline aluminum chloride is heated and decomposed at a lower temperature of about 350 ℃ to 400 ℃, and the generated alumina is amorphous, and is called amorphous alumina.
As shown in fig. 1, the impurity removing device 10 includes a leaching device 11 and a pressurized hydrothermal device 12 located downstream of the leaching device 11, an alumina feeding port and an impurity removing liquid inlet of the impurity removing device 10 are provided in the leaching device 11, and a discharge port of the impurity removing device 10 is provided in the pressurized hydrothermal device 12. With the leaching device 11, the washing filtrate and the amorphous alumina can be mixed in the leaching device 11, so that the washing filtrate is used to remove alkali metal impurities attached to the surface of the alumina. The alkali metal impurities in the alumina grains can be removed at a relatively high temperature and pressure using the pressurized hydrothermal apparatus 12. The impurity removal device 10 with the structure can gradually realize the impurity removal of the alumina, so that the content of the alumina impurities entering the filtering device 20 is lower.
The leaching device 11 is under normal pressure, the leaching temperature is 60-90 ℃, after leaching, filtration and separation are carried out to obtain a filter cake, the obtained filter cake and a hydrochloric acid aqueous solution are mixed and enter a pressurized hydrothermal device 12 for high-pressure leaching, the pH value of the hydrochloric acid aqueous solution is 3-4, the leaching temperature is 110-140 ℃, the leaching pressure is 0.2-0.4Mpa, and a leaching mixture in a colloid state is obtained after high-pressure leaching.
As shown in FIG. 1, the leaching apparatus 11 comprises a plurality of settling tanks 111 which are communicated in sequence, an alumina feed port is provided in the first settling tank 111 in the alumina flowing direction, an impurity removal liquid inlet is provided in the last settling tank 111 in the alumina flowing direction, and the last settling tank 111 in the alumina flowing direction is communicated with the pressurized hydrothermal apparatus 12. By adopting the settling tanks 111 which are sequentially communicated, amorphous alumina can be cleaned and purified step by step in the settling tanks 111, so that the impurity removal capability is provided, and the obtained alumina has lower impurity content.
As shown in fig. 1, each settling tank 111 has an overflow port provided at an upper portion of the settling tank 111, and the height of the overflow ports of the plurality of settling tanks 111 gradually increases in the alumina flow direction, and the overflow port of the succeeding settling tank 111 communicates with the preceding settling tank 111. By adopting the settling tank 111 with the structure, the cleaning filtrate can automatically flow stage by utilizing the height difference, and the cleaning filtrate of the previous settling tank 111 is the cleaning filtrate after the impurity removal of the next settling tank 111, so that the impurity removal precision of the alumina is higher in the flowing direction of the alumina.
In this embodiment, the settling tanks 111 are arranged in a stepped manner, the overflow ports of the settling tanks 111 are arranged on the side surfaces of the settling tanks 111, and the liquid inlets of the settling tanks 111 are arranged on the tops of the settling tanks 111.
Specifically, the difference between the height of the overflow port of the succeeding settling tank 111 and the height of the overflow port of the preceding settling tank 111 in the alumina flow direction is between 0.5m and 0.7 m. By adopting the settling tanks 111 with the height difference, the cleaning filtrate can automatically flow stage by stage, and the cleaning filtrate in each settling tank 111 has enough flow, so that the precipitated alumina cannot flow out.
In this embodiment, the difference between the height of the overflow of the following settling tank 111 and the height of the overflow of the preceding settling tank 111 is 0.5 m.
As shown in FIG. 2, the trash removal device 10 further comprises a driving motor 13 and a stirring paddle 14 in driving connection with the driving motor 13, wherein the stirring paddle 14 is arranged in the settling tank 111. Adopt driving motor 13 can drive stirring rake 14 and rotate to make washing filtrating and aluminium oxide intensive mixing through stirring rake 14's rotation, improve the mixability of washing filtrating and aluminium oxide, thereby improve the edulcoration effect of aluminium oxide.
As shown in fig. 2, the stirring paddle 14 is a double-blade propelling structure, and the stirring paddle 14 with the above structure has the advantages of simple structure and convenient maintenance, and compared with a commonly-used rake, the rotating speed of the stirring paddle can be adjusted, so that the contact effect between alumina and cleaning filtrate is improved.
In this embodiment, the leaching apparatus 11 fully utilizes the advantages of good sedimentation performance and high sedimentation rate of the amorphous alumina, does not need a filter aid and a flocculating agent, and ensures sufficient contact between the amorphous alumina and the washing water through the stirring paddle 14.
As shown in fig. 1, the cross-section of the settling tank 111 is a circular structure, and the ratio of the diameter to the height of the settling tank 111 is between 0.5 and 1. The settling tank 111 adopting the structure utilizes the advantages of good settling performance and high settling rate of the amorphous alumina, realizes that the alumina is quickly settled at the bottom of the settling tank 111, and is delivered to the next-stage settling tank 111 through the settling outlet of the settling tank 111.
In this embodiment, the settling inlet of the settling tank 111 is arranged at the top of the settling tank 111, and the settling outlet of the settling tank 111 is arranged at the bottom of the settling tank 111.
As shown in FIG. 2, two adjacent settling tanks 111 are communicated with each other through a feeding pipe 40, and a feeding pump 41 is arranged on the feeding pipe 40. By adopting the feeding pump 41, the alumina settled in the previous settling tank 111 can be sent to the next settling tank 111 for impurity removal, and the device has the advantages of simple structure and low cost.
In this embodiment, the filtering device 20 comprises a flat disc filter or a tilting disc filter, and the flat disc filter or the tilting disc filter has the advantages of high washing and filtering efficiency, so that the obtained alumina filter cake has higher precision.
In this embodiment, the alumina enters the flat-disc filter or the tilting-disc filter for filtering and washing after being subjected to flash evaporation and sedimentation in the pressurized hydrothermal device 12, the alumina entering the flat-disc filter or the tilting-disc filter is an alumina solution, the alumina entering the flat-disc filter or the tilting-disc filter needs to be subjected to mother liquor separation first and then is cleaned by cleaning water, and the obtained mother liquor and cleaning filtrate enter the leaching device 11 for removing impurities from the amorphous alumina.
The following description is given with reference to specific examples:
in the present embodiment, the settling tank 111 has a height dimension of 1200mm, a diameter of Φ 600mm, and a volume of 350L.
Specifically, the amorphous alumina contains 6.0399% of CaO and 0.5559% of MgO, and enters the leaching device 11 at a flow rate of 130kg/h, the leaching device 11 comprises three settling tanks 111 which are sequentially communicated, and the alumina solution taken out from the last settling tank 111 is tested and analyzed, so that the CaO content in the alumina is 0.6305%, the MgO content in the alumina is 0.1505%, the calcium impurity removal rate is 89.56%, the magnesium impurity removal rate is 72.93%, and most of impurities are removed in the leaching device 11.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
Unless specifically stated otherwise, the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.
In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the orientation words such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, and in the case of not making a contrary explanation, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be interpreted as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.
Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and if not stated otherwise, the terms have no special meaning, and therefore, the scope of the present invention should not be construed as being limited.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. An alumina preparation apparatus, characterized in that the alumina preparation apparatus comprises:
the impurity removal device (10) is provided with an alumina feeding port, a discharge port and an impurity removal liquid inlet;
the filtering device (20) is positioned at the downstream of the impurity removing device (10), the filtering device (20) is provided with a feeding hole, a product outlet, a cleaning water inlet and a filtrate outlet, and the feeding hole of the filtering device (20) is communicated with a discharging hole of the impurity removing device (10);
filtrate groove (30), have and collect the inlet and collect the liquid outlet, the filtrate export of filter equipment (20) with the collection liquid import of filtrate groove (30) is linked together, the collection liquid export of filtrate groove (30) with the edulcoration inlet of edulcoration device (10) is linked together.
2. The alumina preparation plant according to claim 1, wherein the impurity removal device (10) comprises a leaching device (11) and a pressurized hydrothermal device (12) located downstream of the leaching device (11), an alumina feeding port and an impurity removal liquid inlet of the impurity removal device (10) are arranged in the leaching device (11), and a discharge port of the impurity removal device (10) is arranged in the pressurized hydrothermal device (12).
3. The alumina production apparatus according to claim 2, wherein the leaching unit (11) comprises a plurality of settling tanks (111) connected in series, the alumina feed port is provided in a first settling tank (111) in the alumina flow direction, the impurity removal liquid inlet is provided in a last settling tank (111) in the alumina flow direction, and the last settling tank (111) in the alumina flow direction is connected to the pressurized hydrothermal unit (12).
4. The alumina production apparatus according to claim 3, wherein each of the settling tanks (111) has an overflow port provided in an upper portion of the settling tank (111), the level of the overflow ports of the plurality of settling tanks (111) is gradually increased in a flowing direction of alumina, and the overflow port of the succeeding settling tank (111) is communicated with the preceding settling tank (111).
5. The alumina production plant according to claim 4, characterized in that the difference in the alumina flow direction between the height of the overflow of the succeeding settling tank (111) and the height of the overflow of the preceding settling tank (111) is between 0.5m and 0.7 m.
6. The aluminum oxide production equipment according to claim 3, wherein the impurity removing device (10) further comprises a driving motor (13) and a stirring paddle (14) in driving connection with the driving motor (13), and the stirring paddle (14) is arranged in the settling tank (111).
7. The alumina production plant according to claim 6, characterized in that the stirring paddle (14) is of a double-bladed pusher type structure.
8. The alumina production plant according to claim 3, characterized in that the cross section of the settler (111) is of circular configuration, and the ratio of the diameter to the height of the settler (111) is comprised between 0.5 and 1.
9. The aluminum oxide production equipment according to claim 3, wherein two adjacent settling tanks (111) are communicated through a feeding pipe (40), and a feeding pump (41) is arranged on the feeding pipe (40).
10. The alumina production plant according to claim 1, characterized in that the filtering device (20) comprises a flat-disc filter or a tilting-disc filter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221149167.0U CN217431099U (en) | 2022-05-13 | 2022-05-13 | Alumina preparation equipment |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221149167.0U CN217431099U (en) | 2022-05-13 | 2022-05-13 | Alumina preparation equipment |
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| CN217431099U true CN217431099U (en) | 2022-09-16 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115784278A (en) * | 2022-12-06 | 2023-03-14 | 神华准能资源综合开发有限公司 | Method for utilizing water in process of preparing aluminum oxide from aluminum chloride |
-
2022
- 2022-05-13 CN CN202221149167.0U patent/CN217431099U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115784278A (en) * | 2022-12-06 | 2023-03-14 | 神华准能资源综合开发有限公司 | Method for utilizing water in process of preparing aluminum oxide from aluminum chloride |
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